• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.6
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• pp.80-87
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• 2015

In this study, several properties of mortars made with calcium aluminate cement (CAC) such as hydrated products, strength characteristics, absorption, surface electric resistivity and chloride ions penetration resistance were experimentally investigated. The properties of CAC mortars were compared to those of ordinary portland cement (OPC) mortars. From the test results, it was found that the main hydrated products for CAC mortars were of $C_2AH_8$ and $CAH_{10}$, while CH, ettringite and calcite for OPC mortars. The surface electric resistivity and chloride ions penetration resistance of CAC mortars were significantly beneficial compared to those of OPC mortars. However, it should be noted that the absorption properties of CAC mortars were negatively examined. Thus, it needs to have more study for the improvement of surface absorption of CAC matrices. In addition, the combined mixture of CAC and OPC were ineffective to improve some performances of mortars.

• Journal of Cardiovascular Imaging
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• v.31 no.1
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• pp.1-17
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• 2023

The Coronary Artery Calcium Data and Reporting System (CAC-DRS) is a standardized reporting method for calcium scoring on computed tomography. CAC-DRS is applied on a per-patient basis and represents the total calcium score with the number of vessels involved. There are 4 risk categories ranging from CAC-DRS 0 to CAC-DRS 3. CAC-DRS also provides risk prediction and treatment recommendations for each category. The main strengths of CAC-DRS include a detailed and meaningful representation of CAC, improved communication between physicians, risk stratification, appropriate treatment recommendations, and uniform data collection, which provides a framework for education and research. The major limitations of CAC-DRS include a few missing components, an overly simple visual approach without any standard reference, and treatment recommendations lacking a basis in clinical trials. This consistent yet straightforward method has the potential to systemize CAC scoring in both gated and non-gated scans.

• Journal of Engineering Education Research
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• v.19 no.4
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• pp.24-34
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• 2016

There's been few research to study the effects of CAC(Computing Accreditation Committee) evaluation, since start of CAC accreditation 10 years ago. The purpose of this paper is to find what computer engineering graduates perceive the effects of CAC accreditation and to suggest how CAC accreditation process can be improved. The research findings through survey are followings; First, computer engineering graduates' undergraduate education satisfaction is not high enough(3.28). Second, the computer engineering graduates don't recognize CAC accreditation necessary. Third, graduates who work in company chose design courses as the most helpful, while graduates who study in graduate school pursuing further career in master or doctor program chose major subjects. Lastly, graduates from accredited program do not think their completion of accreditation program influence their employment. Strategic approaches to make higher effectiveness of CAC accreditation system are suggested. First, improvement of curriculum and instruction method in CAC accredited program is required to satisfy the needs of students and industry. Second, efforts to inform students of understandings and necessity of accreditation are highly recommended. Third, industrial sector needs to understand CAC accreditation and give graduates from accredited program more incentives. Lastly, government support like Seoul Accord Activation Project should last for a while.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.35S no.3
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• pp.1-8
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• 1998

In this paper, we propose a Neural Call Admission Control (CAC) method using a Sparse Distributed Memory(SDM). CAC is a key technology of TM network traffic control. It should be adaptable to the rapid and various changes of the ATM network environment. conventional approach to the ATM CAC requires network analysis in all cases. So, the optimal implementation is said to be very difficult. Therefore, neural approach have recently been employed. However, it does not mett the adaptability requirements. because it requires additional learning data tables and learning phase during CAC operation. We have proposed a neural network CAC method based on SDM that is more actural than conventioal approach to apply it to CAC. We compared it with previous neural network CAC method. It provides CAC with good adaptability to manage changes. Experimenatal results show that it has rapid adaptability and stability without additional learning table or learning phase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.973-978
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• 2006

This study was conducted to investigate the solubility, antioxidative and antimicrobial activity of the freeze dried chitosan-ascorbate (CAs) and chitosan-acetate (CAc). In the results of solubility, CAs was soluble over 0.5% in distilled water, vinegar, green tea, soju (distilled liquor), beer and red wine, while it was not soluble in soy sauce, soy milk, milk, orange juice, coffee, sesame oil, soy milk and soybean oil. The solubility of CAc in the liquid foods was similar to those of CAs, but it was soluble less than 0.1% in beer, and formed curd in red wine. Electron donating activity, antioxidative activity and SOD activity of CAs were 48.2, 90.6 and 67.5%, respectively, while the activities of the CAc were 0, 40.0 and 10.0%, respectively. The minimal inhibitory concentrations of CAs and CAc were $200\;{\mu}g/disc$ against Bacillus circulans, Bacillus brevis, Bacillus licheniformis, Bacillus arabitane and Bacillus sterothermophillus, $400\;{\mu}g/disc$ against Escherichia coli O157, Listeria monocytogenous, Bacillus cereus and Bacillus subtilis. There was no significant difference in Hunter's L* value between CAs and CAc $(81.95{\sim}82.97)$, but Hunter's a* and b* values of the CAs was higher than those of CAc. While sour and bitter tastes of CAs were lower than those of CAc, there was no significant difference in astringent taste. From these results, it suggested that CAs has more extensive utility in liquid foods with antimicrobial and antioxidant activity as well as sensory quality compared to CAc.

• The Korean Journal of Community Living Science
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• v.18 no.4
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• pp.699-706
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• 2007

The importance of the standards and its related texts established by Codex Alimentarius Commission (CAC) had been increased by the Agreement of Application of Sanitary and Phytosanitary Measures (SPS Agreement) in World Trade Organization (WTO). To meet the needs of WTO SPS Agreement, biennial CAC meeting had been changed to every year. This study was conducted to analyze the effects on interval between CAC meetings. The years of adoption, revision and amendment of CAC texts were collected from the official standard list and individual texts from CAC homepage. The period since establishment of CAC was divided into four groups by starting negotiation of Uruguay Round, WTO foundation and reducing the interval between CAC meetings. The collected data were analyzed by SPSS program. The numbers of CAC standards, guidelines, recommendations, maximum residue levels, and miscellaneous texts were 202, 56, 46, 3 and 5, respectively. Since 8 documents didn't contain the adoption year, these texts were eliminated to analyze adoption year. For adoption, annually 11.26 texts were established since establishment of CAC and there were no significant difference among the 4 groups. However the average numbers of revisions and amendments of adopted texts for overall periods and for each period were 7.56, 0.93, 6.50, 17.20 and 19.75, respectively. The average numbers of overall decisions, defined as summation of adoption, revision and amendment of texts, for overall periods and for each period were 12.37, 6.27, 9.00, 17.40 and 29.25, respectively. There were significant differences by the WTO foundation and the interval between CAC meetings. The reduced interval of CAC meetings influenced to increase number of revisions and amendments of adopted texts, but not yet adoption of new text.

• Journal of Engineering Education Research
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• v.19 no.5
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• pp.35-47
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• 2016

This study analyzed outcomes of CAC(Computing Accreditation Committee) program individually applied in the field of computing engineering since 2007, and draw improvements. Literature review through academic journals, survey research and the FGI(Focus Group Interview) were used to accomplish objectives of the study. In addition, the survey research and FGI were done for professors. For the survey research, nationally 20 out of 44 universities which operates the CAC program were investigated, and sample universities were considered by region. FGI was done to analyze the performance and problems of CAC in more detail for 6 experts. Results of the study were follows as; first, CAC program was activated through the Seoul Accord activation support business by government. Second, BSM(Basic Science and Math), engineering major and engineering design education have been strengthened compared with before and after of CAC introduction in the computing engineering field. Third, soft skills needed for students in the college of engineering have been organized in the professional general curriculum, and professors aware of improvement of ability of the students for the skills. The degree of satisfaction for the CAC program has been examined as normal level, but improvement of educational system and the overall quality enhancement of computing engineering education were affected by CAC program. Nonetheless of positive results of CAC program, incentive system for certification program graduates, the expansion of the autonomy of the department, reduction in the amount of self-evaluation report, and support of administrative human resources were suggested for taking root successfully of CAC program.

• Journal of the Korean Society of Safety
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• v.27 no.4
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• pp.68-75
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• 2012

The biogenic corrosion of mortars adopted in sewage repair by sulfuric acid-producing bacteria was considered in this paper. Calcium aluminate cement (CAC) was known to resist microbiologically-induced corrosion significantly better than portland and blended portland cement.In this study, CAC as well portland cement mortars were tested as main binder to evaluate the corrosion resistance by the chemical immersion test. Replacement ratios of CAC were changed as 0, 20, 40, 50, 60% of OPC binder and 0, 2, 4, 6% of EVA(Ethylene Vinyl Acetate) were also adopted to increase properties of CAC repair mortars in sewage application. Setting time, compressive strength, acid resistance and adhesive strength were measured for various experiments. As a results of the experiments, the proper formulation of repair mortars was found at 40% of CAC and 4% of EVA. Finally, the CAC mortars adopted in field sewer pipe and were demonstrated to superior in adhesion and workability.

• The Journal of the Korea Contents Association
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• v.12 no.4
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• pp.69-75
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• 2012

In this paper, to provide various services of QoS, and moreover applying traffic ratio to CAC(Call Admission Control) algorithm tested how long average data rate and the average packet delay time. When CAC algorithm is not applied, traffic mixture ratio is 1:1:4:4, the FTP Service 0.4, web services 0.6, streaming service 0.7, the packet delay requirements are not satisfied. On the other hand CAC Algorithm is applied, all the service of packet delay are satisfied with arrival rate. Therefore, we can make sure that applying of CAC of traffic control WWW, FTP, Video, VoIP can guarantee the various services of QoS.

• Korean Journal of Radiology
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• v.22 no.11
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• pp.1764-1776
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• 2021

Objective: This study aimed to validate a deep learning-based fully automatic calcium scoring (coronary artery calcium [CAC]_auto) system using previously published cardiac computed tomography (CT) cohort data with the manually segmented coronary calcium scoring (CAC_hand) system as the reference standard. Materials and Methods: We developed the CAC_auto system using 100 co-registered, non-enhanced and contrast-enhanced CT scans. For the validation of the CAC_auto system, three previously published CT cohorts (n = 2985) were chosen to represent different clinical scenarios (i.e., 2647 asymptomatic, 220 symptomatic, 118 valve disease) and four CT models. The performance of the CAC_auto system in detecting coronary calcium was determined. The reliability of the system in measuring the Agatston score as compared with CAC_hand was also evaluated per vessel and per patient using intraclass correlation coefficients (ICCs) and Bland-Altman analysis. The agreement between CAC_auto and CAC_hand based on the cardiovascular risk stratification categories (Agatston score: 0, 1-10, 11-100, 101-400, > 400) was evaluated. Results: In 2985 patients, 6218 coronary calcium lesions were identified using CAC_hand. The per-lesion sensitivity and false-positive rate of the CAC_auto system in detecting coronary calcium were 93.3% (5800 of 6218) and 0.11 false-positive lesions per patient, respectively. The CAC_auto system, in measuring the Agatston score, yielded ICCs of 0.99 for all the vessels (left main 0.91, left anterior descending 0.99, left circumflex 0.96, right coronary 0.99). The limits of agreement between CAC_auto and CAC_hand were 1.6 ± 52.2. The linearly weighted kappa value for the Agatston score categorization was 0.94. The main causes of false-positive results were image noise (29.1%, 97/333 lesions), aortic wall calcification (25.5%, 85/333 lesions), and pericardial calcification (24.3%, 81/333 lesions). Conclusion: The atlas-based CAC_auto empowered by deep learning provided accurate calcium score measurement as compared with manual method and risk category classification, which could potentially streamline CAC imaging workflows.