• Progress in Superconductivity and Cryogenics
• /
• v.17 no.2
• /
• pp.31-35
• /
• 2015

Mapping is a useful tool in the magnetic field analysis and design. In some specific research area, such as the nuclear magnetic resonance (NMR) or the magnetic resonance imaging (MRI), it is important to map the magnetic field in the interesting space with high accuracy. In this paper, an indirect mapping method in the center volume of an air-core solenoid is presented, based on the solution of the Laplace's equation for the field. Through the mathematical analysis on the mapping calculation, we know that the condition number of the matrix, generated by the measurement points, can greatly affect the error of mapping result. Two different arrangement methods of the measurement points in field mapping are described in this paper: helical cylindrical line (HCL) method and parallel cylindrical line (PCL) method. According to the condition number, the HCL method is recommended to measure the field components using one probe. As a simple example, we mapped the magnetic fields in a MRI main magnet system. Comparing the results in the different methods, it is feasible and convenient to apply the condition number to reduce the error in the field mapping calculation. Finally, some guidelines were presented for the magnetic field mapping in the center volume of the air-core solenoid.

• Journal of KIISE:Software and Applications
• /
• v.33 no.1
• /
• pp.114-129
• /
• 2006

Ontology mapping is the task of finding semantic correspondences between two ontologies. In order to improve the effectiveness of ontology mapping, we need to consider the characteristics and constraints of data models used for implementing ontologies. Earlier research on ontology mapping, however, has proven to be inefficient because the approach should transform input ontologies into graphs and take into account all the nodes and edges of the graphs, which ended up requiring a great amount of processing time. In this paper, we propose a multi-strategic mapping approach to find correspondences between ontologies based on the syntactic or semantic characteristics and constraints of the topic maps. Our multi-strategic mapping approach includes a topic name-based mapping, a topic property-based mapping, a hierarchy-based mapping, and an association-based mapping approach. And it also uses a hybrid method in which a combined similarity is derived from the results of individual mapping approaches. In addition, we don't need to generate a cross-pair of all topics from the ontologies because unmatched pairs of topics can be removed by characteristics and constraints of the topic maps. For our experiments, we used oriental philosophy ontologies, western philosophy ontologies, Yahoo western philosophy dictionary, and Yahoo german literature dictionary as input ontologies. Our experiments show that the automatically generated mapping results conform to the outputs generated manually by domain experts, which is very promising for further work.

• Journal of The Korean Association For Science Education
• /
• v.28 no.4
• /
• pp.340-349
• /
• 2008

This study investigated the mapping errors induced in learning the concept of reaction rate with analogies, and compared these mapping errors by the analogy presentation types. Tenth graders (N=418) at a high school were assigned to the four groups by the target concepts and the analogy presentation types. The target concepts were 'concentration and reaction rate' and 'temperature and reaction rate'. In presenting analogy, the verbal and the verbal/pictorial analogs were used. After the students learned one of the analogs, a mapping test was administered. From the analysis, eight types of mapping errors were identified: overmapping, artificial mapping, failure to map, rash mapping, mismapping, mapping of a superficial feature, retention of a base feature, and impossible mapping. According to the analogy presentation types and the features of the target concepts, there were some differences in the frequencies of mapping errors. Educational implications of these findings are discussed.

• Journal of applied mathematics & informatics
• /
• v.26 no.3_4
• /
• pp.757-766
• /
• 2008

We define and characterize a fuzzy pairwise $\gamma$-irresolute open mapping (fuzzy pairwise $\gamma$-irresolute closed mapping) on a fuzzy bitopological space. We also characterize a fuzzy pairwise $\gamma$-irresolute homeomorphism on a fuzzy bitopological space.

• Journal of Computing Science and Engineering
• /
• v.2 no.1
• /
• pp.44-73
• /
• 2008

There is general agreement that the problem of data semantics has to be addressed for XML data to become machine-processable. This problem can be tackled by defining a semantic mapping between an XML schema and an ontology. Unfortunately, creating such mappings is a tedious, time-consuming, and error-prone task. To alleviate this problem, we present a solution that heuristically discovers semantic mappings between XML schemas and ontologies. The solution takes as input an initial set of simple correspondences between element attributes in an XML schema and class attributes in an ontology, and then generates a set of mapping formulas. Once such a mapping is created, it is important and necessary to maintain the consistency of the mapping when the associated XML schema and ontology evolve. In this paper, we first offer a mapping formalism to represent semantic mappings. Second, we present our heuristic mapping discovery algorithm. Third, we show through an empirical study that considerable effort can be saved when discovering complex mappings by using our prototype tool. Finally, we propose a mapping maintenance plan dealing with schema evolution. Our study provides a set of effective solutions for building sustainable semantic integration systems for XML data.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.31 no.6_2
• /
• pp.593-599
• /
• 2013

China's Mapping Satellite-1, developed by the China Aerospace Science and Technology Corporation (CASC), was launched in three years ago. The data from Mapping Satellite-1 are able to use for efficient surveying and geometric mapping application field. In this paper, we fuse the panchromatic and multispectral images of Changchun area, which are obtained from the Mapping Satellite-1, the one that is the Chinese first transmission-type three-dimensional mapping satellite. The four traditional image fusion methods, which are HPF, Mod.IHS, Panshar and wavelet transform, were used to approach for effectively fusing Mapping Satellite-1 remote sensing data. Subsequently we assess the results with some commonly used methods, which are known a subjective qualitative evaluation and quantitative statistical analysis approach. Consequently, we found that the wavelet transform remote sensing image fusion is the optimal in the degree of distortion, the ability of performance of details and image information availability among four methods. To further understand the optimal methods to fuse Mapping Satellite-1 images, an additional study is necessary.

• Journal of the Korea Society of Computer and Information
• /
• v.22 no.7
• /
• pp.1-7
• /
• 2017

As the capacity of NAND flash module increases, the amount of RAM increases for caching and maintaining the FTL mapping information. In order to reduce the amount of mapping information managed in the RAM, a demand-based address mapping method stores the entire mapping information in the flash and some valid mapping information in the form of cache in the RAM so that the RAM can be used efficiently. However, when cache miss occurs, it is necessary to read the mapping information recorded in the flash, so overhead occurs to translate the address. If the RAM space is not enough, the cache hit ratio decreases, resulting in greater overhead. In this paper, we propose a method using two tables called TPMT(Translation Page Mapping Table) and SMT(Segmented Translation Page Mapping Table) to utilize both temporal locality and spatial locality more efficiently. A performance evaluation shows that this method can improve the cache hit ratio by up to 30% and reduces the extra translation operations by up to 72%, compared to the TPM scheme.

• IE interfaces
• /
• v.22 no.1
• /
• pp.17-25
• /
• 2009

In mobile device's user interface, menu organization is very important as well as menu structure because small display of mobile device. Menu items should be organized based on user knowledge structure to design user-centered interface. Traditionally, MDS (Multidimensional Scaling) have been most often used to expose users' perceived organization of menu items. But, information that MDS reveals is just relative spatial location of concepts and not relevant to concepts connection. Unlike MDS, Trajectory Mapping explicitly finds users' cognitive links between perceived concepts. This study proposes a Trajectory Mapping technique for eliciting knowledge structure, especially a set of cognitive pathways linking menu items, from end user. With twelve participants, MDS and Trajectory Mapping were conducted using cellular phone's menu items. And user knowledge structure was analyzed through Visual Concept Map that combination of results of MDS and Trajectory Mapping. After then, menu items were organized according to users' perceived organization. Empirical usability test was also conducted. The results of usability test showed that usability, in terms of task performance time, number of errors, and satisfaction, for newly organized interface was significantly improved compare to original interface. The methodology of this study is expected to be applicable to design a user-centered interface. In other words, Trajectory Mapping technique can be used as a design tool of user interface for imposing user knowledge structure on the interface.

• Journal of KIISE:Computing Practices and Letters
• /
• v.15 no.12
• /
• pp.918-922
• /
• 2009

Naturally, block mapping FTL works well for sequential writes while page mapping FTL does well for random writes. To exploit their advantages, a practical FTL should be able to selectively apply a suitable scheme between page and block mappings for each write pattern. To meet that requirement, we propose a hybrid mapping FTL, which we call Janus-FTL, that distributes data to either block or page mapping areas. Also, we propose the fusion operation to relocate the data from block mapping area to page mapping area and the defusion operation to relocate the data from page mapping area to block mapping area. And experimental results of Janus-FTL show performance improvement of maximum 50% than other hybrid mapping FTLs.

• Journal of the Korean Society for Precision Engineering
• /
• v.23 no.5 s.182
• /
• pp.30-36
• /
• 2006

The participants in collaborative environment want to get the right information or documents which are intended to find. In general search systems, documents which contain only the keywords are retrieved. For searching different word-expressions for the same meaning, we perform mapping before searching. Our mapping-based search approach has two parts, ontology-based mapping logic and ontology libraries. The ontology-based mapping consists of three steps such as character matching (CM), definition comparing (DC) and similarity checking (SC). First, the character matching is the mapping of two terminologies that have identical character strings. Second, the definition comparing is the method that compares two terminologies' ontological definitions. Third, the similarity checking pairs two terminologies which were not mapped by two prior steps through evaluating the similarity of the ontological definitions. For the ontology libraries, document ontology library (DOL), keyword ontology library (KOL), and mapping result library (MRL) are defined. With these three libraries and three mapping steps, an ontology-based search engine (OntSE) is built, and a use case scenario is discussed to show the applicability.