• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 2000.11a
• /
• pp.155-161
• /
• 2000

To improve the vehicle fuel economy, various technologies such as improvement of power train efficiency, use of light weight material, improvement of aerodynamic design, have been studied. One of the possible way to improve the vehicle fuel economy is to reduce the engine friction loss by improving the engine oil characteristics. In the present paper, it was examined the effect of the engine oil viscosity and the addition of friction modifier to engine oil on vehicle fuel economy improvements. Moreover, the effect of engine oil degradation on vehicle fuel economy was examined with two gasoline vehicles and one diesel vehicle by using the fuel economy test facility.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.11 no.8
• /
• pp.4146-4161
• /
• 2017

This study is intended to examine the roles of the social capital and absorptive capacity in technology-intensive firms and verify these roles in an empirical way for the purpose of improving the technology commercialization performance in technology-intensive firms. To achieve the purpose, this study examined the concept and dimensions of social capital through a literature review, empirically verified the effect relationship between the social capital, and absorptive capacity, and technology commercialization performance in technology-intensive firms. This study is meaningful in that it has determined the importance in the formation of social capital and the enhancement of absorptive capacity and suggested strategic directions to improve technology commercialization performance.

• Journal of Information Technology Services
• /
• v.7 no.4
• /
• pp.209-219
• /
• 2008

Recently the number of Internet firms providing useful information like weather forecast data is growing. However most of such information is not prepared in accordance with customers' demand, resulting in relatively low customer satisfaction. To upgrade the service quality, it is recommended to devise a system for customers to get involved in the process of service production, which normally requires a huge investment on supporting computer systems like clusters. In this paper, as a way to cut down the budget for computer systems but to improve the performance, we extend the HPC cluster system to include other Internet servers working independently on the same LAN, to make use of their idle times. We also deal with some issues resulting from the extension, like the security problem and a possible deadlock caused by overload on some non-dedicated nodes. At the end, we apply the technique in the solution of some 2D grid problem.

• Journal of the Korea Society of Computer and Information
• /
• v.7 no.1
• /
• pp.27-32
• /
• 2002

Software reuse was focused for the way of improving programmer productivity from the crisis of software. Object oriented technology impact on overall area of software engineering, such as software analysis , Programming language. testing and maintenance. The new concepts, Class, Inheritance and encapsulation, not only introduce new testing problems and they raise a new challenging question of how to conduct regression testing for 0-0 programs the first problem of regression testing is how to identify the affected components due to the changes of some components. We propose a method firewall to enclose all classes and methods affected by the changes to one or more methods in Inheritance relation

• Journal of Technologic Dentistry
• /
• v.43 no.3
• /
• pp.132-137
• /
• 2021

Purpose: To study the perception and satisfaction of in-person and online classes for dental technology students. Methods: A total of 420 questionnaires were distributed to dental technology students between June 1 and June 30, 2021. Of these, 225 questionnaires were assessed using frequency analysis, one-way analysis of variance, Pearson's Chi-squared test, and independent t-tests via IBM SPSS Statistics ver. 22.0 (IBM). Results: For theory subjects, satisfaction was higher for online classes than in-person classes (p=0.001). For practical subjects, satisfaction was higher for in-person classes than online classes (p=0.002). Both the learning effect and motivation for learning were higher for in-person classes than online classes (p=0.001). Conclusion: When in-person and online classes become coexistent, there should be educational guidelines for improving the quality and effectiveness of learning in these different contexts.

• Transactions of Materials Processing
• /
• v.30 no.5
• /
• pp.247-254
• /
• 2021

This study reviews dynamic deformation behavior of ultra-fine-grained Al alloys, ultra-fine-grained conventional low carbon steel and dual phase steel and Zr-based amorphous alloys. Dynamic tests were conducted using a Kolsky bar then the test data was analyzed in relation to resultant microstructures, mechanical properties and propensity of adiabatic shear band. In addition, deformed microstructures and fracture surfaces were used to investigate the behavior of both the dynamic deformation and fracture, and adiabatic shear banding. As a result, increasing microstructural homogeneity, strain hardenability and forming multiple shear bands could be a better way to increase the fracture resistance under dynamic loading as the formation of adiabatic shear bands was reduced or prevented.

• International Journal of Computer Science & Network Security
• /
• v.23 no.10
• /
• pp.209-213
• /
• 2023

In recent years, the image processing mechanisms are used widely in several medical areas for improving earlier detection and treatment stages, in which the time factor is very important to discover the disease in the patient as possible as fast, especially in various cancer tumors such as the liver cancer. Liver cancer has been attracting the attention of medical and sciatic communities in the latest years because of its high prevalence allied with the difficult treatment. Statistics indicate that liver cancer, throughout world, is the one that attacks the greatest number of people. Over the time, study of MR images related to cancer detection in the liver or abdominal area has been difficult. Early detection of liver cancer is very important for successful treatment. There are few methods available to detect cancerous cells. In this paper, an automatic approach that integrates the intensity-based segmentation and k-means clustering approach for detection of cancer region in MRI scan images of liver.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.37 no.4
• /
• pp.451-456
• /
• 2024

Organic photovoltaic (OPV) devices have attracted attention due to their high efficiency and simple manufacturing process. Applying an overlayer to OPV devices is one way to improve their performance because it can improve charge extraction and suppress vertical phase separation. In addition, dichloromethane (DCM) was used as an orthogonal solvent to minimize the effect on other layers. However, an coating problems due to the use of DCM were found, which affects surface morphology as rough or peeling. Additional research efforts are needed to solve these problems, and optimal results are expected to be obtained by utilizing various buffer layers or selective organic solvents.

• International Journal of Internet, Broadcasting and Communication
• /
• v.12 no.4
• /
• pp.148-155
• /
• 2020

This study investigated learners' perceptions of using self-generated listening materials based on Text to Speech. After taking an online training session to learn how to make listening materials for extensive listening practice outside the classroom, the learners were engaged in practice with self-generated listening materials for 10 weeks in a self-directed way. The results show that a majority of the learners found the TTS-based listening materials helpful to reduce anxiety toward listening and enhance self-confidence and motivation, with a positive effect on improving their listening ability. The learners' general satisfaction can be attributed to some beneficial features of TTS-based listening material, including freedom to choose what they want to learn, convenient accessibility to the material, availability of various native speakers' voices, and novelty of digital tools. This suggests that TTS-based digital listening materials can be a useful educational tool to support learners' self-directed listening practice outside the classroom in EFL settings.

• The Journal of Information Technology and Database
• /
• v.8 no.2
• /
• pp.61-69
• /
• 2001

System Integration Projects, especially in public sector, have a tendency of growing in size and duration. Under such environment the effects of IT personnel turnover becomes a serious problem. In addition a high rate of turnover hinders shill accumulation and competitiveness obtainment. In this research we explored the reasons of turnover by way of tracing IT personnel who have involved in large-scale SI projects and moved or quit before the completion of the projects. Based on previous research we identified three dimensions of variables that affected turnover : task-related dimension, human relations dimension, treatment-related dimension. We used these dimensions as a guideline for the interview and questioning exploration. Implications from the research for improving IT Personnel management are also elaborated.