• Journal of radiological science and technology
• /
• v.45 no.2
• /
• pp.103-109
• /
• 2022

To maintain improved image quality in mammography, the quality control process is performed using the ACR (American college of radiology) phantom. In addition, many studied were performed by fabricating the customized breast phantom to provide more information in mammography. Thus, the purpose of this study was to evaluate the image quality by designing the modified ACR phantoms. The five modified acrlylic ACR phantoms were designed by considering insert position and phantom thickness. The phantoms were consisted of 4.5, 3.0, and 1.5 cm in terms of phantom thickness, and 3.0, 2.0, and 0.5 cm in terms of insert position, respectively. The acquired images were evaluated by PSNR (peak signal to noise ratio), RMSE (root mean square error), CC (correlation coefficient), CNR (contrast to noise ratio), and COV (coefficient of variation). Based on the similarity analysis, the result is suitable between conventional and new designed phantoms. In addition, the CNR and COV results in terms of insert position showed that image quality for 0.5 cm was 2.3 and 27.4% improved compared with 2 and 3 cm, respectively. According to phantom thickness results, the CNR result for 1.5 cm and COV result for 4.5 cm were 50.1 and 62.7% improved compared with that those conditions. In conclusion, we confirmed that the image quality depends on the breast size and thickness through modified ACR phantom study.

• Journal of The Korean Association For Science Education
• /
• v.14 no.2
• /
• pp.214-224
• /
• 1994

The Ministry of Education established the plan to adopt a new college enterance examination system, so called Scholastic Ability Test for college, from 1994. The National Board of Educational Evaluation had carried out 7 experimental trials for the new examination system. Eventhough, the governmental officials advertised the purpose and characteristics of the new examination system, many students and parents did not understand the essential point very well. In this study the researcher tried to analyze the 7 trial examination items and the first Scholastic Ability Test for college carried out 1993. In this study, the researcher tried to find out all the items appeared in the 7 trials. In the analysis, all the individual items from the 1st trial to the 7th trial were used. The research results showed that the items were evenly distributed in all the four areas(Physics, Chemistry, Biology and Earth Science) of science content; however, they were heavily concentrated on data or information analysis categoris in the inquiry domain. In the domain of context, laboratory context was the major item context. The scores were also analyzed. The results showed that no significant difference between male and female students. However, science track students showed higher achievement scores than the non-science track student. The examination result showed high correlation with the tests routinely have carried out in schools. The over all analysis showed the new examination system showed very different characteristics to the conventional tests. Therefore, for the student to get successful result in the Scholastic Ability Test, they should change the way of study. They should try to understand scientific concepts rather than to memorize them. They should invest their time to carry out real experiments rather than to focus on the princples and laws of science. One of the most important thing would be for the student to apply what they learned to real life situations.

• Culinary science and hospitality research
• /
• v.9 no.2
• /
• pp.64-84
• /
• 2003

There is this research that supply better experience and satisfaction of most suitable in users standpoint to users through family restaurant website importance and assessment of satisfaction. Also, there is purpose of this research to supply pendulum in family restaurant internet marketing strategy establishment that website can achieve continuous role as marketing means to be not public information that drive revisit and substantial restaurant visit. Family restaurant website estimation received satisfaction assessment which do not get in importance (expected value) in general as analysis result. In other words, domestic family restaurants website are doing construction. operation by marketing means but real users are various interaction part that can collect and achieve about customer opinion except design part that can do to emboss company's image could see side that satisfaction is unenchanted and presented improvement way in website construction. operation on contents part of various and correct information offer and so on that customer infancy strategy part and user of event and coupon event etc. that is distinction robbers need. Also, realization possibility for restaurant prescription that latent customers who use net can raise family restaurant website revisit and substantial sale could see side. Ditto improvement way in that family restaurants construct and operate website conclusively as a marketing tool that public information is not that three offers satisfaction of most suitable to latent customers who use existent net to website as can achieve continuous role contribute.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.13 no.2
• /
• pp.145-150
• /
• 2002

Background and Objectives : Patients with so-called 'functional voice disorders' who have structurally normal larynges and demonstrate muscle misuse in the larynx, and those with several interacting causes including habitual muscle tension, are probably better defined as having a 'muscle misuse voice disorder'. The purpose of this study was to analyze the voice and effectiveness of voice therapy in patients with functional voice disorders and to provide a guide for the treatment of functional voice disorder. Materials and Method : The records of 35 patients, presenting with functional voice disorder and receiving voice therapy during October, 2001 to September, 2002, were reviewed. Prior to voice therapy, the stroboscopic examination of their larynx, aerodynamic and acoustic analysis was done. The results of voice therapy were compared according to the patient's subjective, perceptual evaluation of voice, and maximal phonation time. Results : Patient's subjective, perceptual evaluation, and maximal phonation time showed superior results after voice therapy. Conclusion : The result of this study indicates that voice therapy is an effective treatment method of patients with functional voice disorder, especially muscular tension dysphonia.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.35 no.11
• /
• pp.1362-1376
• /
• 2011

This study examines the effect of the structural properties of F/W wool knit fabrics for woman's knitwear on the perceptions of textures and sensible images of consumers and present basic data for textile designing by analyzing the relationship among the structural properties, mechanical properties, objective hand measurements and preferences. A total of 12 kinds of knit fabrics were prepared and investigated in terms of the differences in the subjective, mechanical properties and objective hand measurements according to the structural properties of knit fabrics. The data were analyzed by t-test. The subjective hand attributes of wool knits through factor analysis are categorized into 6 factors. In particular, the 'active/comfort' factor is a meaningful result that reflects the unique characteristics of knit fabrics compared to woven fabrics. Mechanical properties and objective hand measurements have a greater effect on textures than on sensible images; in addition, the structural properties, 'gauge' was the most important factor to influence the subjective evaluation.

• Journal of Engineering Education Research
• /
• v.22 no.2
• /
• pp.3-15
• /
• 2019

This study analyzed the evaluations of instructors and experts on flipped learning-based engineering in order to suggest improvement strategies. This study was conducted with 8 engineering courses which participated in the flipped learning course development project of C university from 2017-2018. As a result of the analysis, the instructors and experts pointed out that the pre-learning was not performed and checked effectively. In this regard, the instructors suggested the students' burden of pre-learning, the lack of understanding about flipped learning, and the experts suggested the lack of instructional strategies to facilitate pre-learning. In addition, the instructors and the experts pointed out that the courses were still instructor-centered. The instructors evaluated that they operated the instructor-led course by themselves. In addition, the experts suggested that there was not enough instructional strategies to activate the learner-centered activities. The number of the students and the lecture room environment that were not appropriate for the learner- centered class were the evaluation opinions of both the instructors and the experts. In addition, the professor suggested the lack of understanding and preparation of the flipped learning of the instructors and the learner as the main opinion, and the experts pointed out that the online learning system and classroom was not linked for pre-learning, classroom learning, and the post-learning. Based on these results, suggestions for improvement of flip learning based engineering course were suggested.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.18 no.4
• /
• pp.537-548
• /
• 2020

Currently, radioactive waste for disposal has been restricted to low and intermediate level radioactive waste generated during operation of nuclear power plants, and these radioactive wastes were managed and disposed of the 200 L and 320 L of steel drums. However, it is expected that it will be difficult to manage a large amount of decommissioning waste of the Kori unit 1 with the existing drums and transportation containers. Accordingly, the KORAD is currently developing various and large-sized containers for packaging, transportation, and disposal of decommissioning waste. In this study, the radiation exposure doses of workers and the public were evaluated using RADTRAN computational analysis code in case of the domestic on-road transportation of new package and transportation containers under development. The results were compared with the domestic annual dose limit. In addition, the sensitivity of the expected exposure dose according to the change in the leakage rate of radionuclides in the waste packaging was evaluated. As a result of the evaluation, it was confirmed that the exposure dose under normal and accident condition was less than the domestic annual exposure dose limit. However, in the case of a number of loading and unloading operations, working systems should be prepared to reduce the exposure of workers.

• Journal of KIISE
• /
• v.44 no.5
• /
• pp.553-558
• /
• 2017

With the rapid growth of Big Data, research on extracting meaningful information is being pursued by both academia and industry. Especially, data characteristics derived from analysis, and researcher intention are key factors for search algorithms to obtain accurate output. Therefore, reflecting both data characteristics and researcher intention properly is the final goal of data analysis research. The data analyzed properly can help users to increase loyalty to the service provided by company, and to utilize information more effectively and efficiently. In this paper, we explore various methods of document-evaluation, so that we can improve the accuracy of searching article one of the most frequently searches used in real life. We also analyze the experiment result, and suggest the proper manners to use various methods.

• Journal of the Korea Convergence Society
• /
• v.8 no.2
• /
• pp.163-168
• /
• 2017

The feasibility evaluation of public projects has been carried out mainly in the economic analysis. However, items of political, technological and balanced regional development aspects are further evaluated by applying analytic hierarchy process, This paper suggests to analyzes preliminary feasibility study of construction and research & development project during the past three years and to verify correlation between B/C ratio and AHP weight. The result shows that the correlation between cost benefit ratio and the weight of the hierarchy is 0.744 in construction projects and 0.899 in research & development project. Namely, AHP weight be under the control of B/C ratio and is devoted to its role against expectation. Therefore it must be sufficiently discussed in various designs of studies to maximize the effects of AHP analysis.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.22 no.9
• /
• pp.1153-1158
• /
• 2018

Online customer evaluations and social media information among a variety of information sources are critical for businesses as it influences the customer's decision making. There are limitations on the time and money that the survey will ask to identify a variety of customers' needs and complaints. The customer review data at online shopping malls provide the ideal data sources for analyzing customer sentiment about their products. In this study, we collected product reviews data on the smartphone of Samsung and Apple from Amazon. We applied five classification algorithms which are used as representative sentiment analysis techniques in previous studies. The five algorithms are based on support vector machines, bagging, random forest, classification or regression tree and maximum entropy. In this study, we proposed entropy score which can comprehensively evaluate the performance of classification algorithm. As a result of evaluating five algorithms using an entropy score, the SVMs algorithm's entropy score was ranked highest.