• International Journal of Control, Automation, and Systems
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• 제6권5호
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• pp.670-676
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• 2008

While the matrix converter has many advantages that include bi-directional power flow, a size reduction, a long lifetime, and sinusoidal input currents, it is vulnerable to the input voltage disturbances, because it directly exchanges the input voltage to the output voltage. So, in this paper, a critical evaluation of the effect of various abnormal voltage conditions like unbalanced power supply, balanced non-sinusoidal power supply, input voltage sags and short time blackout of power supply on matrix converter fed induction motor drives is presented. The operation under various abnormal conditions has been analyzed. For this, a 230V, 250VA three phase to three phase matrix converter (MC) fed induction motor drive prototype is implemented using DSP based controller and tests have been carried out to evaluate and improve the stability of system under typical abnormal conditions. Digital storage oscilloscope & power quality analyzer are used for experimental observations.

• International Journal of CAD/CAM
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• 제5권1호
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• pp.69-81
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• 2005

As collaborative design and configuration design gain increasing importance in product development, it becomes essential to exchange parametric CAD models among participants. Parametric CAD models can be represented and exchanged in the form of a macro file or a part file that contains the modeling history of a product. The modeling history of a parametric CAD model contains feature specifications and each feature has selection information that records the name of the referenced topological entities. Translating this selection information requires solving the problems of how to identify the referenced topological entities of a feature (persistent naming problem) and how to convert the selection information into the format of the receiving CAD system (naming mapping problem). The present paper introduces the problem of exchanging parametric CAD models and proposes a solution to naming mapping.

• Asian review of World Histories
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• 제3권1호
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• pp.11-35
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• 2015

Far from being a recent world, the concept of "a [one] world" did slowly emerged in a post-prehistoric Antiquity. The actual knowledge of the world increased through millennia leaving aside large continents (Americas, part of Africa, Australia, etc.-most areas without written history), and writing history in Antiquity cannot be a synchronal presentation of the most ancient times of these areas. Through a few case studies dealing with texts, archaeology and history itself mostly in BCE times, the paper will try to perceive the slow building-up of a physical awareness and 'moral' consciousness of the known world by people of the Middle East (e.g. the Bible, Gilgamesh) and the Mediterranean (mainly Greeks).

• 한국IT서비스학회지
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• 제3권2호
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• pp.85-98
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• 2004

As the e-Commerce based on the XML technology is getting bigger, user authentication, integrity, non-repudiation and confidentiality has become important for security. Since the XML technology is widely used for exchanging information among the Internet e-business systems, the security of XML documents is essentially required and XML digital signature should be supported. To support the digital signature of XML documents, W3C proposed the XML-Signature specification as an international standard that describes five transform algorithms. In this paper, we design and implement a XML/PKI based digital tax invoice system. Our system supports the five transforming algorithms defined in the XML-Signature specification and exchanges digital tax invoices among enterprises securely. We design and implement the flexible and efficient system consists of reusable components using CBD(Component Based Development).

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제2권3호
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• pp.185-190
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• 2002

In distributed autonomous robotic systems (DARS), each robot must behave by itself according to its states ad environments, and if necessary, must cooperate with other robots in order to carry out their given tasks. Its most significant merit is that they determine their behavior independently, and cooperate with other robots in order to perform the given tasks. Especially, in DARS, it is essential for each robot to have evolution ability in order to increase the performance of system. In this paper, a schema co-evolutionary algorithm is proposed for the evolution of collective autonomous mobile robots. Each robot exchanges the information, chromosome used in this algorithm, through communication with other robots. Each robot diffuses its chromosome to two or more robots, receives other robot's chromosome and creates new species. Therefore if one robot receives another robot's chromosome, the robot creates new chromosome. We verify the effectiveness of the proposed algorithm by applying it to cooperative search problem.

• 동아시아경상학회지
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• 제4권4호
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• pp.21-23
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• 2016

There are so much oil and gas reserves in Iran. Therefore extraction from these reserves and sell extracted oil and gas in international markets causes to high oil income for Iran. Especially in some years which oil price increases, our oil income was too high. In this paper, we want to reveal that, high oil income is not cause to rise of nonoil export. For this aim, we use from data of 1971-2013 and with Johansen co-integration test and Error Correction Model (ECM) extract short run and long run relations. Results of estimation reveal that in Iran high oil income is not cause to many non oil exports in long run and short run. Therefore, we should allocate oil income to import industrial machines and reallocate them to agriculture and industrial sectors which causes to raise national production which will cause to high non oil export. Then, in this condition, our needy exchanges are provided from non oil export and our dependence to oil income will be declined.

• International Journal of Oral Biology
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• 제43권1호
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• pp.1-3
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• 2018

Blockchain is at the center of attention recently and it is expected to have a huge impact on healthcare industry including dentistry as well. Blockchain is a fundamental technology behind Bitcoin and itis all about decentralization, security, reliability, and transparency. These characteristics of the technology empower it to disrupt the current healthcare industry in innumerable practices such as supply chain management in pharmaceuticals to prevent the counterfeited medicine, clinical trials to guarantee transparency, healthcare information exchanges or personal health record systems to ensure data integrity and interoperability, etc. It will surely revolutionize the way the current healthcare system works; from provider-oriented to patient-centered. Hence, it is time to seriously consider how we could be a part of this blockchain revolution in dentistry.

• Asian Journal of Business Environment
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• 제2권1호
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• pp.19-23
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• 2012

The economic exchanges have become increasingly frequent between China and Korea and the average annual growth rate of the total trade volume has increased by 30% since the establishment of diplomatic relations between the two countries. With the rapid economic growth and industrial upgrading of China, there are changes in the investment of Korea in China and domestic demand of China, and the trade structure of Sino- Korea has changed a lot in recent years. The changes have mainly manifested in the following aspects, including the increased proportion of high-tech products, raw materials and the intra-industry trade, the decreased proportion of consumer goods, the inter-industry trade and the trade deficit of China. With the development of the situation of international economy, the scale of Korea and China trade will continue to expand and the structure of Korea and China trade will also keep on changing in the long run.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.158-162
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• 2013

Building envelope systems with growing complexity in geometry and performance criteria demand adapted workflow processes toward the efficient integration of their design and fabrication. To facilitate integration of the workflow process, this study analyzes relationships among teams who share digital models and exchange information that help project participants identify areas of improvement in task allocation and exchanges among various actors, systems, and activities. In addition, major gaps identified in knowledge transfer, project tracking, and design integration during the performance evaluation stages, emphasize the need for a more comprehensive approach to integrating the design, the fabrication, and the construction parameters of building envelope systems. To evaluate the effectiveness of streamlining interactions of design parameters with fabrication constraints and constructability assessments, this paper examines a mechanical design approach as it applies to various project scenarios to develop a mechanical solution for streamlining building envelope design and construction workflow.

• Educational Technology International
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• 제13권1호
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• pp.175-205
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• 2012

The current study investigated whether SNS such as Twitter can be an assisting tool to compensate the limitations of online learning from social-affective and cognitive perspectives. Such limitations include low level of motivation to participate, feeling of isolation, rare exchanges of ideas and feedback from peers or instructors. This paper reports findings from a research study on the use of Twitter in online learning in Higher Education. Survey and subsequent interviews were conducted to examine students' perceptions about the cognitive and social-affective aspects of their participation in Twitter activities. Some of the challenges and potentials in integrating Twitter into online course are also addressed. It can be concluded that Twitter contributes not only to building close relationships among peers and instructors but also to opening a communication channel that can extend cognitive potentials.