• Journal of the Korean Society for Precision Engineering
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• v.19 no.11
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• pp.112-119
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• 2002

Generally, it is very difficult to inspect geometric shape of large 2D objects after machining. To maintain the accuracy for inspection, a robot vision is used to divide overall shape into several enlarged images, and image processing technique is applied to acquire one minute geometric contour. The inspection is to compare the NC data with the measured contour data by the vision system, and the algorithm is to rotate to minimize the maximum deviation after coinciding two geometric centers. This paper experimentally shows that the proposed algorithm is very useful for inspection of large machined objects.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.831-832
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• 2006

In this paper, we introduce a canonical framework of the large-scaled web-based sensor gateway and practically implement it as the environment monitoring system. The system consists of a central management server, up to 250 local embedded subsystems and up to 250 sensor or actuator nodes for each subsystem. The node information is gathered periodically through a well-defined protocol on the sensor network and converted to the web contents and the SNMP MIB objects according to its data type. The MIB objects are well-defined and include system, network, sensor, actuator and alarm specific data classes. Because there is an increasing trend that a large number of sites are willing to adapt unmanned sensing and control, the developed system will play a key role to efficiently manage a large scale sensor networked system such as environment monitoring systems or countermeasure systems against disaster and calamities.

• The Transactions of the Korea Information Processing Society
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• v.6 no.11
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• pp.3034-3045
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• 1999

For efficiently providing multimedia services, distributed computing environments are specified the requirements of various services and distributed object platforms applied an object-oriented technology by TINA Consortium and OMG CORBA. Because multimedia service applications are becoming large and distributing, their servicing managing interfaces among objects are being complicated. In order to solve these defects, it is necessary to suggest a new object grouping model and specify object service/management requirements can be introduced under the object groups. We have been developed the distributed object group platform that can group all individual objects by the relating services and can supply trading functions for interconnecting between distributed objects or object groups. In this paper, we designed and implemented the Virtual Drawing Board for remote equational services on the distributed object group platform we mentioned above. As results, we designed a basic structure and service interfaces, and showed execution procedures of VDB system consisted of distributed objects and objects groups for educational services. For supporting distributed services of VDB system, we used three kinds of tools as follows; IONA orbix 2.2 of CORBA compliance as an object middleware, OrbixTrader 1.0 for interconnection of distributed objects, and the OGTG we developed for interconnection of distributed object groups and checking access rights of objects included in an arbitrary object group.

• Journal of Internet Computing and Services
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• v.15 no.2
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• pp.33-39
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• 2014

How to transfer spatial data from server to client in wireless broadcasting environment is shown as following: A server arranges data information that client wants and transfers data by one-dimensional array for broadcasting cycle. Client listens data transferred by the server and returns resulted value only to server. Recently number of users using location-based services is increasing alongside number of objects, and data volume is changing into large amount. Large volume of data in wireless broadcasting environment may increase query time of client. Therefore, we propose Client based Data Scheduling (CDS) for efficient data scheduling in wireless broadcasting environment. CDS divides map and then calculates total sum of objects for each grid by considering number of objects and data size within divided grids. It carries out data scheduling by applying hot-cold method considering total data size of objects for each grid and number of client. It's proved that CDS reduces average query processing time for client compared to existing method.

• Journal of KIISE:Software and Applications
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• v.26 no.11
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• pp.1306-1313
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• 1999

본 연구는 인터넷 기반 공유가상공간에서 시스템의 확장성을 유지하기 위하여 이동객체를 대상으로 하는 이벤트 필터링 기법을 제안하고자 한다. 제안된 다중격자 모델 기법은 이동객체의 경로 상에서 대표적인 이벤트를 샘플링하는 방식을 사용한다. 이 방식은 메시지 트래픽의 양을 동적으로 조절하기 위하여 이동객체 간의 관심정도 정보를 수치적으로 변환하여 이벤트 갱신빈도에 반영한다. 대량의 이동객체를 생성하여 제안된 기법을 적용한 성능평가 실험에서 기존의 방식에 비하여 평균 메시지 전송량이 50%이상 감소하는 것으로 확인할 수 있었다. 다중격자 모델은 참여자의 수와 메시지 트래픽 상황에 따라 가상환경의 공유 QoS를 동적으로 조절할 수 있으며, 인터넷 상에서 다수 사용자를 위한 3차원 가상사회 구축 및 온라인 네트워크 게임 개발 등에 활용될 수 있을 것이다.Abstract This paper proposes an event filtering technique that can dynamically control a large amount of event messages produced by moving objects like avatars or autonomous objects in a distributed virtual environment. The proposed multi-level grid model technique uses the method that extracts the representative events from the paths of moving objects. For dynamic control of message traffics, this technique digitizes the DOIs of the avatars and reflects the interest information controlling the frequency of message transmission. For the performance evaluation, a large number of moving objects were created and the model was applied to these avatar groups. In the experiments, more than 50% of messages have been reduced in comparison with the existing AOI-based filtering techniques. The proposed technique can dynamically control the QoS in proportion to the number of users and the amount of messages where a large number of users share a virtual space. This model can be applied to the development of 3D collaborative virtual societies and multi-user online games in the Internet.

• International Commerce and Information Review
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• v.11 no.4
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• pp.77-109
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• 2009

The purpose of this study is to review the current trend of FDIs by Korean companies into EU, and to present the optimal strategies for them to combine their firm-specific factors and FDI attractiveness of the regions in EU. The companies are divided into two categories, SMEs and large enterprises. The regions of EU are composed of 15 incumbent members before the fifth enlargement in 2004 and 12 new members. Large Korean companies tend to make large investments in 15 incumbent members with stable and mature markets. Korean SMEs, by contrast, mainly invest on small scales in the new members due to the lack of their available inner resources and knowledge for the markets. The main objects of the investments in EU by the large Korean companies are to gain more market share and to acquire the advanced technologies. Although such goals are also important for the SMEs, the most important objects for the investments by Korean SMEs in EU are usually to enter EU markets and to take advantage of the relatively cheap labor forces for the efficient operations. The effects of such passive strategies by the SMEs, however, are expected to extinct because the cost advantages in regions of the new EU members will not last in the long term, so the SMEs must take longer views for the choice of locations. Many empirical results suggest that the optimal FDI strategies for the Korean companies in EU could be worked mainly by more aggressive localization policy of companies and by the cooperations of SMEs and large enterprises for the reduction in costs of foreignness.

• Journal of Korea Society of Digital Industry and Information Management
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• v.12 no.4
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• pp.115-121
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• 2016

Recently, it has become an important problem to extract semantic objects from videos, which are useful for improving the performance of video compression and video retrieval. In this thesis, an automatic extraction method of moving objects of interest in video is suggested. We define that an moving object of interest should be relatively large in a frame image and should occur frequently in a scene. The moving object of interest should have different motion from camera motion. Moving object of interest are determined through spatial continuity by the AMOS method and moving histogram. Through experiments with diverse scenes, we found that the proposed method extracted almost all of the objects of interest selected by the user but its precision was 69% because of over-extraction.

• Proceedings of the Korea Society for Simulation Conference
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• 1999.10a
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• pp.325-330
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• 1999

Web-based simulation is one of the most interesting field of simulation research today. Among many research area of web-based simulation, we concern about what a effective way of building simulation model is since creating comprehensive simulation models can be expensive and time consuming. So this paper discusses how to integrate distributed simulation sub-models as objects for constructing the required simulation model which is more large and complex. We introduce two web-oriented methodologies (such as JIDL, CORBA) and the concepts of agent for assisting modelers to integrate simulation models scattered over the web. SINDBAD, which we designed, is a simulation environment which makes it possible constructing a simulation model with distributed model objects on the web and performing the parallel simulation in a distributed way. It is organized according to design patterns in the object oriented concept. Actually we are on the premise that all the distributed objects are originally composed in a CORBA-compatible way to start with our prototype of SINDBAD.

• Journal of The Korean Astronomical Society
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• v.30 no.1
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• pp.83-94
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• 1997

We have identified the candidates for the primordial galaxies in the process of formation in the Hubble Deep Field (hereafter HDF). In order to select these objects we have removed objects brighter than 29-th magnitude in the HDF images and smoothed the maps with the Gaussian filters with the FWHM of 0.8' and 4' to obtain the difference maps. This has enabled us to find. very faint diffuse structures close to the sky level. Peaks are identified in the difference map for each of three HDF chips with three filters (F450W, F606W, and F814W). They have the apparent AB magnitudes typically between 29 and 31. The objects identified in different wavelengths filters have a strong cross-correlations. The correlation lengths are about 0.8'. This means that an object found in one filter can be also found as a peak within 0.8' separation in another filter, thus telling the reality of the identified objects. This angular scale is also the size of the primordial galaxies which have strong color fluctuations on their surfaces. Their large-scale distribution quite resembles that of nearby galaxies, supporting the idea that these objects are ancestors of the present bright galaxies forming at statistically high density regions. Inspections on individual objects show that these primordial galaxy candidates have tiny multiple glares embedded in diffuse backgrounds. Their radial light distributions are quite different from that of nearby bright galaxies. We may be now looking at the epoch of galaxy formation.

• Journal of Korea Spatial Information System Society
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• v.5 no.2 s.10
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• pp.5-21
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• 2003

Sptaio-temporal databases are important to store the real-time location information of large spatio-temporal objects efficiently and retrieve them rapidly. Accordingly necessity for spatio-temporal database system that can manage spatial information, aspatial information and temporal information of spatio-temporal objects is increasing. Sptaio-temporal databases are important to store the real-time location information of large spatio-temporal objects efficiently and retrieve them rapidly. Accordingly necessity for spatio-temporal database system that can manage spatial information, aspatial information and temporal information of spatio-temporal objects is increasing. Therefore, in this paper, we propose a spatio-temporal data model that is able to efficiently manage historical spatio-temporal objects that change dynamically their states as time. Also, various spatio-temporal operations and constraint conditions are defined to keep integrity of spatio-temporal data and spatio-temporal operations.