• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.800-804
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• 1995

The complex permeability dispersions and the microwave absorbing phenomena are investigated in ferrite microwave absorber. The complex permeability of NiZn ferrite, NiZnCo ferrite, and Y-type hexagonal ferrite were measured in 200MHz-14GHz range. Two types of resonances, the domain wall and the spin rotational resonance, were observed. With a ferrite particle with a diameter of about $1\;\mu\textrm{m}$, only spin rotational resonance were observed. The theoretical matching frequency is determined by plotting the measured complex permeability locus on the impedance matching solution map. One or two impedance matching phenomena are observed in the ferrite absorbers according to their complex permeability loci on the impedance matching solution map. The first matching frequency, found in the ferrite-rubber composites, which was higher than that of spin rotational resonance, increased with spin rotational resonance frequency.

• Journal of the Korean Ceramic Society
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• v.32 no.1
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• pp.25-30
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• 1995

The frequenc dependence of magnetic permeability($\mu$r) and dielectric constant($\varepsilon$r) in MHz-GHz frequency range and their relationships with microwave absorbing properties were investigated in sintered and composite Ni-Zn ferrites, respectively. It was confirmed that zero reflection condition was required the real parts of permeability and permittivity in sintered specimen, and the complex permeability, permittivity and dielectric loss tangent in composite specimen. The real part of permittivity varied with the replacement of nickel by manganese in sintered Ni-Zn ferrite. Therefore, we could control the matching frequency and matching thickness.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1482-1485
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• 2005

An equivalent schema matching among several different source schemas is very important for information integration or mining on the XML based World Wide Web. Finding most similar source schema corresponding mediated schema is a major bottleneck because of the arbitrary nesting property and hierarchical structures of XML DTD schemas. It is complex and both very labor intensive and error prune job. In this paper, we present the first complex matching of XML schema, i.e. XML DTD, inlining two dimensional DTD graph into flat feature values. The proposed method captures not only schematic information but also integrity constraints information of DTD to match different structured DTD. We show the integrity constraints based hierarchical schema matching is more semantic than the schema matching only to use schematic information and stored data.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.3 no.1
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• pp.32-36
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• 2003

An equivalent schema matching among several different source schemas is very important for information integration or mining on the XML based World Wide Web. Finding most similar source schema corresponding mediated schema is a major bottleneck because of the arbitrary nesting property and hierarchical structures of XML DTD schemas. It is complex and both very labor intensive and error prune job. In this paper, we present the first complex matching of XML schema, i.e. XML DTD. The proposed method captures not only schematic information but also integrity constraints information of DTD to match different structured DTD. We show the integrity constraints based hierarchical schema matching is more semantic than the schema matching only to use schematic information and stored data.

• 한국가시화정보학회:학술대회논문집
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• 2004.12a
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• pp.57-63
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• 2004

various applications is presented. It is based on rapid-prototyping of transparent model for flow visualization and on the use of refractive index matching that enables efficient and clear visualization of the flow inside the model. The model is immersed in the index-matching fluid in a glass tank so that any displacement and rotation of the model in the tank have no influence on the optical setup for image acquisition to be made through a glass wall. This can facilitate greatly the camera calibration for stereo PIV and 3-D PTV. As the flow model is generated directly from 3-D surface data, no laborious preparation of the flow model is needed. This approach for seamless linking of model generation and PIV measurement is applicable to various flow measurements in automobile, ship building, fluid machinery, turbine, electrical appliances, heat exchanger, electronic cooling, bio-engineering and so on.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.5
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• pp.841-849
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• 2001

The pixel information of the object was obtained sequentially and pixels were clustered to a label by the line labeling method. Feature points were determined by finding the slope for edge pixels after selecting the fixed number of edge pixels. The slope was estimated by the least square method to reduce the detection error. Once a matching point was determined by comparing the feature information of the object and the pattern, the parameters for translation, scaling and rotation were obtained by selecting the longer line of the two which passed through the matching point from left and right sides. Finally, modified Hausdorff Distance has been used to identify the similarity between the object and the given pattern. The multi-label method was developed for recognizing the patterns with more than one label, which performs the modified Hausdorff Distance twice. Experiments have been performed to verify the performance of the proposed algorithm and method for simple target image, complex target image, simple pattern, and complex pattern as well as the partially hidden object. It was proved via experiments that the proposed image matching algorithm for recognizing the object had a good performance of matching.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.10
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• pp.1024-1029
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• 2003

This paper presents the complex antenna factor of a top-hat EMI monopole antenna for measuring time domain electromagnetic fields. The approach is facilitated by adding a artificial parallel ground plane above the monopole antenna. This allows use of cylindrical harmonic field expansions in each of three subregions enclosed by the two ground plane. The results show that the complex antenna factor of the top-hat monopole antenna does not diverge at low frequencies. When compared with a monopole antenna, the top-hat monopole antenna has broadband characteristics. In order to verify the availability of the mode-matching method, the input impedance of the antenna were compared with experiments.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.49-54
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• 2008

This study is to investigate an optimal size and position of PV system for apartment complex enough the electrical load matching analysis. The 4 types of arrangements of apartment buildings are considered as follows; ㅡtype, alternative ㅡtype, ㄱtype and ㅁtype. We assume that the studied site is composed of 9 buildings. Firstly, solar access evaluation of roof and facade in apartment buildings was performing with the hourly simulations of total received insolation on each surface considering the hading effect of buildings. Electrical load profile of typical Korean apartments was investigated for the lad matching analysis. To calculate an annual total PV output, we used MERIT program which is a sourly based load matching tool developed by ESRU. TRY weather data of Daejeon are applied for this analysis. Result shows that approximately 11% of total electric load of the site can be supplied by the PV system in the case of full installation of PV system at the whole south-face roof area of 9 buildings in this stuided apartment complex. Depending of a various installation option of roof and facade area, the possible ratio of PV supply in total electrical load varies from 9% to 42%. Among the 4 arrangement types, the ㅡ type revealed the best option for the maximum output of PV system.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.580-583
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• 2007

Various matching methods have been introduced by investigators to improve digital elevation model (DEM) accuracy of satellite imagery. This study proposed an area-based matching method according to land cover property using correlation coefficient of pixel brightness value between the two images for DEM generation from IKONOS stereo imagery. For this, matching line (where "matching line" implies straight line that is approximated to complex nonlinear epipolar geometry) is established by exterior orientation parameters to minimize search area. The matching is carried out based on this line. Land cover classes are divided off into water, urban land, forest and agricultural land. Matching size is selected using a correlation-coefficient image in the four areas. The selected sizes are $81{\times}81$ pixels window, $21{\times}21$ pixels window, $119{\times}119$ pixels window and $51{\times}51$ pixels window in the water area, urban land, forest land and agricultural land, respectively. And hence, DEM is generated from IKONOS stereo imagery using the selected matching sizes and land cover map on the four types.

• Journal of KIISE:Databases
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• v.33 no.7
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• pp.727-740
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• 2006

Schema matching is important as a prerequisite to the transformation of XML documents. This paper presents a schema matching method for the transformation of XML documents. The proposed method consists of two steps: preliminary matching relationships between leaf nodes in the two XML schemas are computed based on proposed ontology and leaf node similarity, and final matchings are extracted based on a proposed path similarity. Particularly, for a sophisticated schema matching, the proposed ontology is incrementally updated by users' feedback. furthermore, since the ontology can describe various relationships between concepts, the proposed method can compute complex matchings as well as simple matchings. Experimental results with schemas used in various domains show that the proposed method is superior to previous works, resulting in a precision of 97% and a recall of 83 % on the average. Furthermore, the dynamic ontology increased by 9 percent overall.