• Journal of Korean Ophthalmic Optics Society
• /
• v.9 no.1
• /
• pp.1-9
• /
• 2004

In this study, we presented a research about the development of the phoropter simulation program for education using the 3-D virtual reality in order to study the ophthalmic optics rather efficiently. Especially, by putting the facility such as the refractive error analysis of the eyeball in the cyber tutor inside, we have made the learner to learn and confirm the present situation of refractive correction through refractive power of principal meridians. By organizing the system which induces the active involvement of the learner and showing the result of the execution to the learner intuitively, the implementation of the more efficient education-environment can be possible. Consequently, it is expected that this program will be greatly helpful for the optician training as well as the ophthalmic optics education. As a next phase of study, we will develope the development technique of this simulator more and extend the cyber tutor contents more and make the web service version of this program to be provided through the internet network in order to inspire the learning desire of the learner more and more.

• Computers and Concrete
• /
• v.26 no.3
• /
• pp.203-211
• /
• 2020

Turkey is located in one of the most seismically active regions of in Europe. The majority of the population living in big cities are at high seismic risk due to insufficient structural resistance of the existing buildings. Such a seismic risk brings the need for a comprehensive seismic evaluation based on the risk analysis in Turkey. Determining the seismic resistance level of existing building stock against the earthquakes is the first step to reduce the damages in a possible earthquake. Recently in January 2020, the Elazig earthquake brought the importance of the issue again in the public. However, the excessive amount of building stock, labor, and resource problems made the implementation phase almost impossible and revealed the necessity to carry out alternative studies on this issue. This study aims for a detailed investigation of residential buildings in Antalya, Turkey. The approach proposed here can be considered an improved state of building survey methods previously identified in Turkey's Design Code. Antalya, Turkey's fifth most populous city, with a population over 2.5 Million, was investigated as divided into sub-regions to understand the vulnerability, and a threshold value found for the study area. In this study, 26,610 reinforced concrete buildings between 1 to 7 stories in Antalya were examined by using the rapid visual assessment method. A specific threshold value for the city of Antalya was determined with the second level examination and statistical methods carried out in the determined sub-region. With the micro zonation process, regions below the threshold value are defined as the priority areas that need to be examined in detail. The developed methodology can be easily calibrated for application in other cities and can be used to determine new threshold values for those cities.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.1
• /
• pp.420-426
• /
• 2011

In this paper, we introduce a system which helps to draw a conceptual class diagram from the problem description by combining various class diagram deriving methods. Generally, problem description is a kind of statements including user requirements in the early development phase. The system developer can derive a conceptual class diagram from this document, which playes an important role during the object-oriented software development. Until now, it is not easy for the novice to elicit classes because it requires good experience and intuition. In addition, there are also some difficulties of finding valid conceptual classes by hand when the size of system becomes larger. Therefore, we develop a system to solve these problems so that the developer is able to construct the conceptual class diagram easily.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.10
• /
• pp.2750-2759
• /
• 2009

In this paper, we analyze vulnerabilities in a remote authentication protocol using smartcards which was proposed by Bindu et al. and propose an improved scheme. The proposed scheme can prevent from restricted replay attack and denial of service attack by replacing time stamp with random number. In addition, this protocol can guarantee user anonymity by transmitting encrypted user's ID using AES cipher algorithm. The computational load in our protocol is decreased by removing heavy exponentiation operations and user efficiency is enhanced due to addition of password change phase in which a user can freely change his password. Furthermore, we really implement the proposed authentication protocol using a STM smartcard and authentication server. Then we prove the correctness and effectiveness of the proposed remote authentication system.

• The Journal of the Acoustical Society of Korea
• /
• v.23 no.2
• /
• pp.117-124
• /
• 2004

In this paper, we have been implemented the QPSK-based underwater transmission systems using DSP in order to transmit the underwater image data. We have adopted a BDPA (Block Data Parallel Architecture) to control multiple DSPs used in the transmitter and receiver in order to transmit the image data in real-time. We also have developed GUI software in order to drive and to debug the implemanted system in real-time. We have executed open sea tests in order to analyze the performance of the implemented system at East Sea near Kosung in Kangwon-Do. As a result of these experiments, it has been demonstrated that 10 kbps image data can be received without errors at 30m and 80m depth points, while the distance between the transmitter and the receiver is up to 20m.

• Journal of KIISE:Computing Practices and Letters
• /
• v.13 no.2
• /
• pp.86-99
• /
• 2007

Packet filtering is to filter out potentially malicious network packets. In order to test a packet filtering function we should verify whether security policies are performed correctly as intended. However there are few existing tools to test the function. Besides, they need user participation when generating test cases or deciding test results. Many security administrators have a burden to test systematically new security policies when they establish new policies or modify the existing ones. To mitigate the burdens we suggest a new test method with minimal user articipation. Our tool automates generation steps of the test cases and the test oracles, respectively. By using the test oracles generated automatically, deciding test results is possible without user intervention. Our method realizes an automatic testing in three phases; test preparation phase, test execution, and test evaluation. As a result it may enhance confidence of test activities more highly. This paper describes the design and implementation of our test method and tool.

• Journal of Advanced Navigation Technology
• /
• v.15 no.6
• /
• pp.1212-1219
• /
• 2011

As recently Privacy Acts in Korea enforced in domestic companies' personal information management needs of a growing obligation for the safety measures and the right of personal information collection, use, limitations, management, and destroyed specifically for handling personal information. Such this regulations should be required technical and policy supports. Accordingly, for the enterprise incident has occurred, the personal information management system behave correctly operating to verify that the safety measures taken, and be determined by the specific preparation to be done. So the first, preparation phase corresponds to the upcoming digital forensic investigation model. On the other hand, the response team also carried these measures out correctly, it needs to be done to check the compliance of Privacy Act. Thus a digital forensics investigation model is strictly related with the implementation of the Privacy Acts and improve the coping strategies are needed. In this paper, we suggest a digital forensic investigation model corresponding to Privacy Act.

• Journal of Advanced Navigation Technology
• /
• v.17 no.4
• /
• pp.442-448
• /
• 2013

I&C (Instrumentation & Control) system is different from information system and the security design of the two systems are also different. The modeling activity is needed based on the security control guide in order to build I&C system security control. In this paper, the role and by the security control, we designed the relationship (that is, the relation schema) between the documents for 'The system for supporting the cyber security control of I&C system design' based on the security control guide. The designed schema plans 'The system for supporting the cyber security control of I&C system' for observing the security control guide, and is used as the database and content that supports its design and implementation. The process and system of the proposed schema is utilized and designed. The design of the schema and system is intensified in the design phase with the proposed mode and supporting the I&C system cyber security design.

• International Journal of Contents
• /
• v.14 no.3
• /
• pp.7-16
• /
• 2018

The extent and depth of the event plan determines the scope of pedagogical experience in situations and consequently the quality of immersive learning based on our simulated world. In contrast to planning in conventional narrative-based systems mainly pursuing dramatic interests, planning in virtual world-based pedagogical systems strive to provide realistic experiences in immersed situations. Instead of story plot comprising predetermined situations, our inter-event planning method aims at simulating diverse situations that each involve multiple events coupled via their associated agents' conditions and meaningful associations between events occurring in a background world. The specific techniques to realize our planning method include, two-phase planning based on inter-event search and intra-event decomposition (down to the animated action level); autonomous and independent agents to behave proactively with their own belief and planning capability; full-blown background world to be used as the comprehensive stage for all events to occur in; coupling events via realistic association types including deontic associations as well as conventional causality; separation of agents from event roles; temporal scheduling; and parallel and concurrent event progression mechanism. Combining all these techniques, diverse exogenous events can be derived and seamlessly (i.e., semantically meaningfully) integrated with the original event to form a wide scope of situations providing chances of abundant pedagogical experiences. For effective implementation of plan execution, we devise an execution scheme based on multiple priority queues, particularly to realize concurrent progression of many simultaneous events to simulate its corresponding reality. Specific execution mechanisms include modeling an action in terms of its component motions, adjustability of priority for agent across different events, and concurrent and parallel execution method for multiple actions and its expansion for multiple events.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.3 no.3
• /
• pp.165-172
• /
• 1998

The electromechanical energy conversion conditioning and processing implementation in USM direct motion control system is generally divided into two power stages: the two-phase high-frequency ac power inversion stage for driving piezoelectric ceramic PZT transducer array off the USM stator and the mechanical thrust power conversion stage based on the frictional force between the piezo electric stator array and the rotary slider of the USM. However, the dynamic and steady-state mathematical modeling of the USM is extremely default from a theoretical point of view because it contains many complicated an nonlinear characteristics dependant on operation temperature. In +2$0^{\circ}C$~3$0^{\circ}C$, the operating characteristics of the USM has represented normal condition. But the other temperature, it has abnormal condition so that driving frequency, current and motor speed will be down. The recent USM has controller without temperature compensation. This study represents the fuzzy controller for speed compensation according to operating temperature by driving frequency.