• Journal of The Korean Association of Information Education
• /
• v.2 no.2
• /
• pp.162-173
• /
• 1998

Writing a CAI program containing Chinese characters requires a common Chinese character code to share information for educational purposes. A Chinese character code setting needs to allow a mixed use of both vowel and stroke order, to represent Chinese characters in simplified Chinese as well as in Japanese version, and to have a conversion process for data exchange among different sets of Chinese codes. Waste in code area is expected when vowel order is used because heteronyms are recognized as different. However, using stroke order facilitates in data recovery preventing duplicate code generation, though it does not comply with the phonetic rule. We claim that the first and second level Chinese code area needs to be expanded as much as academic and industrial circles have demanded. Also, we assert that Unicode can be a temporary measure for an educational code system due to its interoperability, expandability, and expressivity of character sets.

• Journal of the Korea Convergence Society
• /
• v.8 no.11
• /
• pp.7-13
• /
• 2017

In recent years, cloud computing technology has been socially emerged that provides services remotely as various devices are used. However, there are increasing attempts by some users to provide cloud computing services with malicious intent. In this paper, we propose a property - based multi - level hierarchical approach to facilitate authentication access for users accessing servers in cloud environment. The proposed method improves the security efficiency as well as the server efficiency by hierarchically distributing a set of attribute values by replacing the order of the user 's attribute values in the form of bits according to a certain rule. In the performance evaluation, the proposed method shows that the accuracy of authentication according to the number of attributes is higher than that of the existing method by an average of 15.8% or more, and the authentication delay time of the server is decreased by 10.7% on average. As the number of attributes increases, the average overhead change is 8.5% lower than that of the conventional method.

• The KIPS Transactions:PartB
• /
• v.13B no.5 s.108
• /
• pp.569-578
• /
• 2006

The present study implemented AAC(Augmentative and Alternative Communication) system using images that speech defectives can easily understand. In particular, the implementation was focused on the portability and mobility of the AAC system as well as communication system of a more flexible form. For mobility and portability, we implemented a system operable in mobile devices such as PDA so that speech defectives can communicate as food as ordinary People at any Place using the system Moreover, in order to overcome the limitation of storage space for a large volume of image data, we implemented the AAC system in client/server structure in mobile environment. What is more, for more flexible communication, we built an image dictionary by taking verbs as the base and sub-categorizing nouns according to their corresponding verbs, and regularized the types of sentences generated according to the type of verb, centering on verbs that play the most important role in composing a sentence.

• Proceedings of the Korean Society For Composite Materials Conference
• /
• 2005.11a
• /
• pp.179-184
• /
• 2005

In the present study, conceptual design of the main wing for 20 seats WIG{wing in Ground Effect) flight vehicle, which will be a high speed maritime transportation system for the next generation, was performed. The high stiffness and strength Carbon-Epoxy material was used for the major structure and the skin-spar with a foam sandwich structural type was adopted for improvement of lightness and structural stability. As a design procedure for this study, firstly the design load was estimated with maximum flight load, and then flanges of the front and the rear spar from major bending load and the skin structure and the webs of the spars were preliminarily sized using the netting rules and the rule of mixture. In order to investigate the structural safety and stability, stress analysis was performed by Finite Element Codes such as NASTRAN/PA TRAN[6] and NISA II [7]. From the stress analysis results, it was confirmed that the upper skin structure between the front spar and rear spar was very unstable for the buckling. Therefore in order to solve this problem, a middle spar and the foam sandwich structure at the upper skin and the web were added. After design modification, even thought the designed wing weight was a little bit heavier than the target wing weight, the structural safety and stability of the final design feature was confirmed. Moreover, in order to fix the wing structure at the fuselage, the insert bolt type structure with six high strength bolts was adopted for easy assembly and removal.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.25 no.3
• /
• pp.537-547
• /
• 2001

The paper proposes the fuzzy logic global approximate optimization strategies in optimal sizing of automotive A-pillar trim with rib structures for occupant head protection. Two different strategies referred to as evolutionary fuzzy modeling (EFM) and neuro-fuzzy modeling (NFM) are implemented in the context of global approximate optimization. EFM and NFM are based on soft computing paradigms utilizing fuzzy systems, neural networks and evolutionary computing techniques. Such approximation methods may have their promising characteristics in a case where the inherent nonlinearity in analysis model should be accommodated over the entire design space and the training data is not sufficiently provided. The objective of structural design is to determine the dimensions of rib in A-pillar, minimizing the equivalent head injury criterion HIC(d). The paper describes the head-form modeling and head impact simulation using LS-DYNA3D, and the approximation procedures including fuzzy rule generation, membership function selection and inference process for EFM and NFM, and subsequently presents their generalization capabilities in terms of number of fuzzy rules and training data.

• KEPCO Journal on Electric Power and Energy
• /
• v.3 no.2
• /
• pp.89-97
• /
• 2017

The substation is a critical node in the power network where power is transformed in the power generation, transmission and distribution system. The IEC 61850 is a global standard which proposes efficient substation automation by defining interoperable communication and data modelling techniques. In order to achieve this level of interoperability and automation, the IEC 61850 (Part 6) defines System Configuration description Language (SCL). The SCL is an XML based file format for defining the abstract model of primary and secondary substation equipment, communications systems and also the relationship between them. It enables the interoperable exchange of data during substation engineering by standardizing the description of applications at different stages of the engineering process. To achieve the seamless interoperability, multi-vendor devices are required to adhere completely to the IEC 61850. This paper proposes an efficient algorithm required for verifying the interoperability of multi-vendor devices by checking the adherence of the SCL file to specifications of the standard. Our proposed SCL validation algorithm consists of schema validation and other functionalities including information model validation using UML data model, the Vendor Defined Extension model validation, the User Defined Rule validation and the IED Engineering Table (IET) consistency validation. It also integrates the standard UCAIUG (Utility Communication Architecture International Users Group) Procedure validation for quality assurance testing. Our proposed algorithm is not only flexible and efficient in terms of ensuring interoperable functionality of tested devices, it is also convenient for use by system integrators and test engineers.

• Ocean and Polar Research
• /
• v.25 no.4
• /
• pp.545-555
• /
• 2003

It is widely known that compare to many other countries, the U.S.A. has a strong framework for efficient implementation of mitigation policy to protect wetlands. As indicated in many strong mitigation initiatives, mitigation policy primary requires avoidance rule for wetland damage and if a developer inevitability damages wetlands, the development should be minimize, and as a last resort, the policy impose legal duty that a developer should compensate wetland corresponding to the damaged wetlands. However, the legal system fur Korea's mitigation system does not provide any legal duty for the compensatory mitigation, although the possibility of creation of tidal flat is casually expressed in several Korean legal systems. Therefore, without any strong and enforceable legal system, Korean mitigation system cannot efficiently protect Korea's vast and productive wetlands. To introduce mitigation policy similar to the U.S.A. in Korea, we suggest that there (a) should be a strongly policy which regulate legal duty for the compensatory mitigation, (b) should be an improve management system for actively corresponding to special knowledge relating to environment, and lastly, (c) should be a system which consider a class action introduced in environmental regime for a long term protection of tidal wetlands for future generation.

• Journal of Korea Multimedia Society
• /
• v.16 no.5
• /
• pp.637-646
• /
• 2013

In order to model a variety of natural trees that are appropriate to outdoor terrains consisting of multiple trees, this study proposes a modeling method of new growth rules(based on the convolution sums of divisor functions). Basically, this method uses an existing growth-volume based algorithm for efficient management of the branches and leaves that constitute a tree, as well as natural propagation of branches. The main features of this paper is to introduce the theory of convolution sums of divisor functions that is naturally expressed the growth or fate of branches and leaves at each growth step. Based on this, a method of modeling various tree is proposed to minimize user control through a number of divisor functions having generalized generation functions and modification of the growth rule. This modeling method is characterized by its consideration of both branches and leaves as well as its advantage of having a greater effect on the construction of an outdoor terrain composed of multiple trees. Natural and varied tree model creation through the proposed method was conducted, and using this, the possibility of constructing a wide nature terrain and the efficiency of the process for configuring multiple trees were evaluated experimentally.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.10 no.3
• /
• pp.608-613
• /
• 2006

There are many e-showing mall because of revitalization of e-commerce system. It is necessary to recommending system of products that is for saving time and effort of customer. In this paper, we propose the system that is applying classification among data mining techniques to analysis of log data of customer. This log data contains access of user and purchasing of products. The proposed system operates in two phases. The first phase is composed of data filter module and association extraction module among web pages. The second phase is composed of personalization module and rule generation module. Customer can easily know the recommended sites because the proposed system can present rank of the recommended web pages to customer. As a result, the proposed system can efficiently do recommending of products to customer.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.24 no.5
• /
• pp.443-451
• /
• 2006

DEM has been used for various purposes overall fields of engineering, the fields of civil engineering, military, communication, environment, and so forth and its applications are being extending increasingly. It is well hewn that LiDAR DEM is definitely superior to the other surveying methods. But LiDAR DEM run short of a full study about vertical accuracy. In order to assess LiDAR DEM, total 35 stations were selected and surveyed by GPS for utilizing as reference data. And then accuracy of LiDAR DEM was analyzed by comparison between both LiDAR DEM and CPS surveying. The RMSE of ${\pm}0.109m$ was shown in vertical direction. It is within the permissible accuracy required for mapping on a scale of 1 to 500 and 1 to 1000 on the mapping rule notified by the National Geographic Information Institute. It is expected that the results of this study will be fully used in the field of large scale DEM generation and be utilized as basic information in applied field of LiDAR DEM.