• Nuclear Engineering and Technology
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• v.41 no.1
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• pp.79-90
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• 2009

Verification of programmable logic controller (PLC) programs written in IEC 61131-3 function block diagram (FBD) is essential in the transition from the use of traditional relay-based analog systems to PLC-based digital systems. This paper describes effective use of the well-known verification tool VIS for automatic verification of behavioral equivalences between successive FBD revisions. We formally defined FBD semantics as a state-transition system, developed semantic-preserving translation rules from FBD to Verilog programs, implemented a software tool to support the process, and conducted a case study on a subset of FBDs for APR-1400 reactor protection system design.

• Journal of Engineering Education Research
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• v.26 no.1
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• pp.12-19
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• 2023

With the introduction of the accreditation of engineering programs in Korea, universities affiliated with the programs have opened introductory engineering design courses for first- or second-year students. Since these courses mainly aim at cultivating problem-solving skills through team projects, this type of classes has opened as face-to-face classes. However, from the beginning of 2020, online teaching was recommended or forced on universities due to the COVID-19 pandemic. Thus, effective design of online courses on introductory engineering design was inevitable during the period. In this paper, we introduce a case study of the course in the Department of Computer Science at S University in Fall 2021. Through concrete suggestions on project areas, selection of team members considering grade levels and interest, several systems for prevention of free riding, and carefully designed open-book exams, the course resulted in both high achievements and high satisfaction.

• International Journal of Computer Science & Network Security
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• v.23 no.4
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• pp.134-138
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• 2023

The field of digital forensics requires good theoretical and practical knowledge, so practitioners should have an in-depth understanding and knowledge of both theory and practical as they need to take decisions which impacts human lives. With the demand and advancements in the realm of digital forensics, many universities around the globe are offering digital forensics programs, but there is a huge gap between the skills acquired by the student's and the market needs. This research work explores the problems faced by digital forensics programs, and provides solution to overcome the gap between the skills acquired by the student's and the market needs using Activity led learning pedagogy for digital forensics programs.

• Korean Journal of Environmental Agriculture
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• v.12 no.1
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• pp.69-80
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• 1993

Environmental hazards of a chemical could be assessed by two different approaches : toxicity test and assessment of exposure potentials to human and environmental organisms. For the prediction of environmental fate of chemicals three available computer programs were compared each other and were verified. The results obtained by using these computer programs, PCHEM, EXAMS, and E4CHEM were summarized as follows. The estimated octanol/water partition coefficients by PCHEM were similar to the experimental values in the literature. But the other factors, water solubility and vapor pressure were different from the data in the literature. The simulation results of selected compounds by EXAMS showed similar tendency to the literature results of model field environment. Therefore, this computer program could be utilized to predict the environmental fate of chemicals. E4CHEM program is very simple and this program could predict the ultimate environmental fate of stable chemicals by input of two or three parameters. However, the validity should further be verified in the future field study using more compounds. It is suggested that these approaches could be fully utilized by understanding their limitations to predict the environmental fate of new chemicals under development, to screen the potential environmental pollutants among chemicals already-in use, and to devise measures to minimize the hazards to the environment.

• Journal of the Korean GEO-environmental Society
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• v.5 no.1
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• pp.47-54
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• 2004

The several computer programs for the design of soil nailed wall are often used in Korea. However, these programs have been used without any practical justification. Therefore, in order to evaluate the applicability of these programs for the design of soil nailing, these computer results were analyzed and compared with one another. The performance evaluations by the available programs, such as SNAILZ, TALREN97, SLOPE/W, STABL6, and NAILM16, were applied and the applied data were from 5 case history(15 section). The estimated factors of safety with available programs were compared with observed horizontal deformation from the field. The results showed that the program SNAILZ is most adequate tool for the design of soil nailed wall.

• Journal of Computing Science and Engineering
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• v.6 no.2
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• pp.105-118
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• 2012

We propose two new approaches that automatically parallelize Java programs at runtime. These approaches, which rely on run-time trace information collected during program execution, dynamically recompile Java byte code that can be executed in parallel. One approach utilizes trace information to improve traditional loop parallelization, and the other parallelizes traces instead of loop iterations. We also describe a cost/benefit model that makes intelligent parallelization decisions, as well as a parallel execution environment to execute parallelized programs. These techniques are based on Jikes RVM. Our approach is evaluated by parallelizing sequential Java programs, and its performance is compared to that of the manually parallelized code. According to the experimental results, our approach has low overheads and achieves competitive speedups compared to the manually parallelizing code. Moreover, trace parallelization can exploit parallelism beyond loop iterations.

• Journal of Computing Science and Engineering
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• v.11 no.2
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• pp.69-77
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• 2017

Recent GPUs have adopted cache memory to benefit general-purpose GPU (GPGPU) programs. However, unlike CPU programs, GPGPU programs typically have considerably less temporal/spatial locality. Moreover, the L1 data cache is used by many threads that access a data size typically considerably larger than the L1 cache, making it critical to bypass L1 data cache intelligently to enhance GPU cache performance. In this paper, we examine GPU cache access behavior and propose a simple hardware-based GPU cache bypassing method that can be applied to GPU applications without recompiling programs. Moreover, we introduce a hybrid method that integrates static profiling information and hardware-based bypassing to further enhance performance. Our experimental results reveal that hardware-based cache bypassing can boost performance for most benchmarks, and the hybrid method can achieve performance comparable to state-of-the-art compiler-based bypassing with considerably less profiling cost.

• Journal of the Korea Society of Computer and Information
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• v.7 no.4
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• pp.220-234
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• 2002

This study examined the impact of preventive environmental management practices on sales growth, manufacturing and environmental performance of the US chemical manufacturing companies. In order to investigate the impact, this study examined the relationship between the degree of preventive environmental programs and sales growth, manufacturing and environmental performances. Using a cross-sectional research design to test three hypotheses. a survey questionnaire was mailed to chemical companies in the USA. To investigate the relationship between the degree of Preventive environmental programs and sales growth, manufacturing and environmental performances. t-tests were used. According to the results of t-tests the higher preventive implementation programs achieved better manufacturing and environmental performances than lower preventive or reactive strategies. But there was no difference in sales growth between tow groups.

• Journal of The Korean Association of Information Education
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• v.14 no.2
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• pp.139-148
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• 2010

This study aimed to develop the teacher training programs to prevent and treat of game addiction. First, we analyzed the existing training programs concerning game addiction and searched for various strategies applicable to game addiction prevention and treatment education programs. On this ground, training programs were divided into three courses that were the prevention program for normal students, the treatment program I for students in the potential-risk group, and the treatment program II for those in the high-risk group. For the prevention program, commonalities were drawn and developed from the existing studies and training programs; and for treatment programs, game addiction clinic centers were analyzed to draw various useful strategies and contents. We also developed the details of those programs in consultation with experts. As a result of content validity about the developed teacher training program to prevent and treat of game addiction, this program was generally appropriate and acceptable. We expect that the developed programs help to treat a student who has game addiction effectively.

• The KIPS Transactions:PartC
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• v.8C no.6
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• pp.741-756
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• 2001

With the development of computer systems, there has been a sharp increase in the threats on these systems including attacks by malicious programs such as virus, vandal, etc. Currently virus vaccines are widely used to thwart these threats, but they have many weaknesses. They cannot guard against unknown threats and sometimes, they also cannot detect the existence of malicious programs before these malicious programs make any destructive results. For lack of an efficient security model, the existing security programs have the problem that they raise many false-positive alarms in spite of normal action. So it becomes very important to develop the improved security program that can make up for the weakness of the existing computer security program and can detect many threats of malicious programs as early as possible. In this paper we describe the design of an improved security model and the implementation of a security program that can filter and handle the threats on computer systems at the kernel level in real time.