• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.6
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• pp.141-152
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• 2015

Most of agricultural structures are consisted of complex components and exposed to various boundary conditions. There have been no ways to express those structures exactly for model experiment. As an alternative, 3D printer can produce any type of solid model. However, there are limited informations related to structural experiments using 3D printer. The object of this study gives the basic informations to structural engineers who try to use 3D printer for model experiment. When PLA was used as a supplier for 3D printer, the outcomes showed less heat deformation to compare with ABS. To test the material properties, two kinds of experiments (three-point flexibility test and compression test) were executed using universal testing machine. In three-point flexibility test, plastic hinge and its deformation were developed as observed in material such as steel. The behavior was in a linear elastic state, and elastic bending modulus and yield force were evaluated. In the compression test using unbraced columns with hinge-hinge boundary condition, the constant yield forces were observed regardless of different lengths in all columns with same section size, whereas the compressive elastic modulus was increased as the length of column was increased. The suggested results can be used for model experiments of various agricultural structures consisted of single material.

• Journal of Korean Academy of Nursing
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• v.34 no.8
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• pp.1499-1508
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• 2004

Purpose. The primary purpose of this study was to reexamine underlying dimensions of attitudes toward the elderly held by undergraduate nursing students. A secondary purpose was to investigate characteristics of nursing students associated with attitudes toward elders. Methods. A survey was performed using self-report questionnaire completed by nursing students from a total of 10 nursing schools or departments each selected randomly from one province of Korea. Students' responses (N=366) were analyzed using factor analysis, correlation coefficients, t-test, and ANOVA. Results. Three attitudinal dimensions explaining $35.29\%$ of the variance were extracted: vitality, generosity and flexibility. From a neutral point of 4.0 in the range of 1 to 7, only generosity (4.47) was evaluated positively, whereas vitality (3.31) and flexibility (2.91) were evaluated negatively. The mean scores of the vitality and generosity dimensions were significantly different by students' level of communication with the elderly, experience living with the elderly, and interest in elders or in issues related to elders. Interest in elders/elder issues was the only characteristic affecting significant mean score difference in flexibility. Conclusion. Educational process should increase students' exposure to healthy elderly to modify negative attitudes toward the elderly among nursing students.

• Journal of the Microelectronics and Packaging Society
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• v.28 no.2
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• pp.89-94
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• 2021

The mechanical reliability of flexible devices has become a major concern on their commercialization, where the importance of reliable bonding is highlighted. In terms of component materials' properties, it is important to consider thermal damage of polymer substrates that occupy large area of the flexible device. Therefore, room temperature bonding process is highly advantageous for implementing flexible device assemblies with mechanical reliability. Conventional epoxy resins for the bonding still require curing at high temperatures. Even after the curing procedure, the bonding joint loses flexibility and exhibits poor fatigue durability. To solve this problems, low-temperature and adhesive-free bonding are required. In this work, we develop a room temperature bonding process for polymer substrates using carbon nanotube heated by microwave irradiations. After depositing multiple-wall carbon nanotubes (MWNTs) on PET polymer substrates, they are heated locally with by microwave while the entire bonding specimen maintains room temperature and the heating induces mechanical entanglement of CNT-PET. The room temperature bonding was conducted for a PET/CNT/PET specimen at 600 watt of microwave power for 10 seconds. Thickness of the CNT bonding joint was very thin that it obtains flexibility as well. In order to evaluate the mechanical reliability of the joint specimen, we performed lap shear test, three-point bending test, and dynamic bending test, and confirmed excellent joint strength, flexibility, and bending durability from each test.

• Journal of the Korean Ceramic Society
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• v.39 no.7
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• pp.675-679
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• 2002

To produce a strengthened glass, single ion exchange properties such as three-point bend strength and residual stress were investigated in soda-lime-silicate substrate glass for display use. The present work showed that the maximum value of strength was 62.5${\times}$10$\sub$6/ kg/㎡ after, the two-step single ion exchange process at 470$^{\circ}C$ for 1 h and 450$^{\circ}C$ for 24 h. As the result of the fracture analysis after bending test, the residual stress on the fractured surface of the strengthened glass increased the flexibility by means of absorbing the elastic deformation energy in the glass. Also, the effects of absorbing the elastic deformation energy were analysed by curvature change, number of multiple crack branches and brittleness.

• The Journal of Korean Association of Computer Education
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• v.16 no.6
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• pp.11-19
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• 2013

Recently, the discussion of domain-generality vs. domain-specificity of creativity has been continued. At this point in time, we need to research computer programming activities related to creativity again. While most of existing relative researches have performed TTCT figural tests for evaluating learners' creativity of learning education programming language, our perspective is that verbal creativity is needed on learning education programming language more. In this research, we have developed scratch programming learning based on CPS with the contents using fundamental concepts of computer science from the viewpoint of that programming is a kind of learning required verbal thinking style. This learning program was applied to 17 students of 4th and 5th grade for each 4 classes in 5 days, total 20 classes, this group passed normality test has the result of t-test has found that three subscales (fluency, flexibility and originality) and creativity index (mean of three standard scores) of verbal creativity were improved significantly using the mean of standard scores (100) of TTCT verbal tests as the test value.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.10a
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• pp.449-456
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• 1999

The concrete wall is the most useful of retaining structure which can obtain the engineering stability, but has problems that is not friendly with nature environment in a fine view, such as poor rear drainage, and shrinkage crack by temperature difference, etc. Because of this problems, the research for a segmental crib retaining wall has been performed. A segmental crib retaining wall is quickly and easily erected because is possible to be erected as the individual members, and is not sensitive to differential settlement and earthquakes. Also, it shows effective drainage and has a friendly advantage with nature environment because of being able to be planted with vines and shrubs in retaining walls The design of crib retaining walls has traditionally been based on classical soil mechanics theories. These theories, originally derived by Rankine(1857) and Coulomb(1776), assume that the wall acts as a rigid body. This assumption results in failure being predicted by either monolithic overturning or base sliding mechanisms. However, the wall consists of individual members which have been created a three dimensional grid. This grid confines an fill mass which becomes part of the wall. The filled wall resists the earth pressure with the same mechanism of classical gravity walls. Because of the flexibility of the individual segment, it allows relative movement between the individual members within the wall. The three dimensional flexible grid leads to stress redistribution when the wall is subjected to external or fill loads. Due to the flexibility and the stress redistribution, the failure of segmental crib wall consists of not only overturing and base sliding but the local deformation and the failure between the segmental members. It has been researched in the field that due to this flexibility and load redistribution, serviceability failure of segmental crib walls is unlikely to be due to overturning or base sliding. Therefore, in this study, the relative displacement appearance of retaining wall due to variation of inclination is measured to examine this behavior characteristics. Also, the behavior characteristics of retaining walls by surcharge load, and location of acting point of retaining wall rear, and the displacement characteristics and deflections are estimated about the existence and nonexistence of Rear Stretcher performing an role in transmitting earth pressure of Header and Stretcher organizing retaining walls. This research focuses on the characteristics due to the behavior of retaining walls. This research focuses on the characteristics due to the behavior of retaining walls.

• Asia Marketing Journal
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• v.15 no.2
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• pp.133-173
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• 2013

Consumers empty perfectly safe to intake perishable foods everyday if they are older than what prints on expiration date. The variation in expiration dating is freshness labeling represented in various terms such as sell by, package, best before, and so on. Regardless of the terms used and meanings are attached, consumers tend to conceive of freshness labeling on food as end of its shelf-life. Consequently, the food waste becomes a big issue for businesses in food sector. In an effort to demonstrate flexibility on this, KFDA(Korea Food & Drug Administration) introduced "best before" date in domestic market place to reduce food waste, based on the food safety test conducted by KCA(Korea Consumer Agency 2009). The results indicated freshness labeling on food should not be considered as the end of its life. Current study examined the underlying mechanisms(i.e. risk perception, self-construals, and indecisiveness) that influence consumers' intention on prolonged consumption of food beyond its stamped date when the KCA test results are shown to them. In addition, the moderating effect of regulatory focus is tested in the causal relationships between underlying mechanisms and different groups of prolonged consumption intention. Study participants are divided into three groups of prolonged consumption intention: no-change, moderate-change, and wide-change. The group with moderate-change in intention being as our point of reference, logistic regression analyses are conducted on 276 sample population. The results indicated that consumers with high source credibility risk are likely to show wide-change in intention on prolonged consumption while physical risk did not show significance. The consumers with independent self-construal are likely to show no-change in intention on prolonged consumption while interdependent self-construal did not show significance. Indecisiveness showed association a group with wide-change in intention on prolonged consumption. The moderating effect of regulatory focus showed valid results in most situations; the promotion-focused consumers showed wide-change in intention, while prevention-focused consumers showed no-change in intention. Furthermore, the moderating effect of promotion-focus showed a dominant position over the causal effect of indecisiveness in which decisive consumers(i.e. no-change in intention); if they are promotion-focused they tend show for the wide-change in intention instead. It is important to note that for those promotion-focused consumers(or situations), promotion-related arguments are more effective, while for those prevention-focused consumers(or situations) prevention- related arguments are more effective means of persuasion.

• Journal of Intelligence and Information Systems
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• v.23 no.2
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• pp.1-17
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• 2017

The deep learning framework is software designed to help develop deep learning models. Some of its important functions include "automatic differentiation" and "utilization of GPU". The list of popular deep learning framework includes Caffe (BVLC) and Theano (University of Montreal). And recently, Microsoft's deep learning framework, Microsoft Cognitive Toolkit, was released as open-source license, following Google's Tensorflow a year earlier. The early deep learning frameworks have been developed mainly for research at universities. Beginning with the inception of Tensorflow, however, it seems that companies such as Microsoft and Facebook have started to join the competition of framework development. Given the trend, Google and other companies are expected to continue investing in the deep learning framework to bring forward the initiative in the artificial intelligence business. From this point of view, we think it is a good time to compare some of deep learning frameworks. So we compare three deep learning frameworks which can be used as a Python library. Those are Google's Tensorflow, Microsoft's CNTK, and Theano which is sort of a predecessor of the preceding two. The most common and important function of deep learning frameworks is the ability to perform automatic differentiation. Basically all the mathematical expressions of deep learning models can be represented as computational graphs, which consist of nodes and edges. Partial derivatives on each edge of a computational graph can then be obtained. With the partial derivatives, we can let software compute differentiation of any node with respect to any variable by utilizing chain rule of Calculus. First of all, the convenience of coding is in the order of CNTK, Tensorflow, and Theano. The criterion is simply based on the lengths of the codes and the learning curve and the ease of coding are not the main concern. According to the criteria, Theano was the most difficult to implement with, and CNTK and Tensorflow were somewhat easier. With Tensorflow, we need to define weight variables and biases explicitly. The reason that CNTK and Tensorflow are easier to implement with is that those frameworks provide us with more abstraction than Theano. We, however, need to mention that low-level coding is not always bad. It gives us flexibility of coding. With the low-level coding such as in Theano, we can implement and test any new deep learning models or any new search methods that we can think of. The assessment of the execution speed of each framework is that there is not meaningful difference. According to the experiment, execution speeds of Theano and Tensorflow are very similar, although the experiment was limited to a CNN model. In the case of CNTK, the experimental environment was not maintained as the same. The code written in CNTK has to be run in PC environment without GPU where codes execute as much as 50 times slower than with GPU. But we concluded that the difference of execution speed was within the range of variation caused by the different hardware setup. In this study, we compared three types of deep learning framework: Theano, Tensorflow, and CNTK. According to Wikipedia, there are 12 available deep learning frameworks. And 15 different attributes differentiate each framework. Some of the important attributes would include interface language (Python, C ++, Java, etc.) and the availability of libraries on various deep learning models such as CNN, RNN, DBN, and etc. And if a user implements a large scale deep learning model, it will also be important to support multiple GPU or multiple servers. Also, if you are learning the deep learning model, it would also be important if there are enough examples and references.