• Proceedings of the Korean Magnestics Society Conference
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• 2014.11a
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• pp.71-71
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• 2014

• Journal of KIISE:Databases
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• v.32 no.2
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• pp.129-141
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• 2005

Although spatio-temporal databases have received considerable attention recently, there has been little work on processing range sum queries on the historical records of moving objects despite their importance. Since to answer range sum queries, the direct access to a huge amount of data incurs prohibitive computation cost, materialization techniques based on existing index structures are recently suggested. A simple but effective solution is to apply the materialization technique to the MVR-tree known as the most efficient structure for window queries with spatio-temporal conditions. However, the MVR-tree has a difficulty in maintaining pre-aggregated results inside its internal nodes due to cyclic paths between nodes. Aggregate structures based on other index structures such as the HR-tree and the 3DR-tree do not provide satisfactory query performance. In this paper, we propose a new indexing technique called the Adaptive Partitioned Aggregate R-Tree (APART) and query processing algorithms to efficiently process range sum queries in many situations. Experimental results show that the performance of the APART is typically above 2 times better than existing aggregate structures in a wide range of scenarios.

• The Journal of Korean Institute for Practical Engineering Education
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• v.5 no.1
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• pp.58-65
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• 2013

The purpose of this study was to develop field-centered educational system in contract based department using DACUM for occupational group in software development and materialization area. Job model for contract based department was developed and both educational need and appropriate educational method was investigated and analyzed. Then, knowledge, skill and attitude were elicited and categorized. Subjects for S-OJT were organized and hierarchy of subjects was constructed according to career path set by job experts. Then, educational system in contract based department for software development and materialization was developed by connecting developed subjects with former curriculum. Based on this result the directions for the future studies was discussed.

• Journal of KIISE:Databases
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• v.28 no.4
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• pp.587-595
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• 2001

Precomputation and materialization of parts. commonly called views of a data cube is a common technique in data warehouses The view is defined as the result of a query which is defined through aggregate functions In this paper we introduce the concept of fine granule view. The fine granule view is the result of a query defined through aggregate functions and the range on each dimension, where the subdivision of each dimension is based on queries access patterns. For the representation and selection of fine granule views to materialize, we define the ANO-OR cube graph and AND-OR minimum cost graph. With these structures, we propose a fine granule view materialization method. And through experiments, we evaluate the performance of the proposed method.

• The monthly packaging world
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• s.257
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• pp.44-57
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• 2014

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.422-428
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• 2002

In this study, actuator, sensor, guide, power transmission element and control method are considered for ultra-precision positioning apparatus. Through previous process, single plane X-Y stage with ultra-precision positioning is manufactured. Global stage for the purpose of materialization with robust system, is combined by using AC servo motor and ball screw and rolling guide. And ultra-precision positioning system is developed by micro stage with elastic hinge type and piezo element. global servo and micro servo for the purpose of materialization positioning accuracy with nm(nanometer) are controlled simultaneously by using incremental encoder and laser interferometer as displacement measurement sensor. Through previous process, ultra-precision positioning system (100mm stroke and ${\pm}$ 10nm positioning accuracy) with single plane X-Y stage are materialized.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.5
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• pp.65-72
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• 2002

In this study, actuator, sensor, guide, power transmission element and control method are considered for ultra-precision positioning apparatus. Through previous process, single plane X-Y stage with ultra-precision positioning is manufactured. Global stage for the purpose of materialization with robust system, is combined by using AC servo motor and ball screw and rolling guide. And ultra-precision positioning system is developed by micro stage with elastic hinge type and piezo element. global servo and micro servo for the purpose of materialization positioning accuracy with nm(nanometer) are controlled simultaneously by using incremental encoder and laser interferometer as displacement measurement sensor. Through previous process, ultra-precision positioning system(100mm stroke and $\pm$ l0nm positioning accuracy) with single plane X-Y stage are materialized.

• Proceedings of the Optical Society of Korea Conference
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• 2009.10a
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• pp.377-378
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• 2009

• Journal of KIISE:Databases
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• v.30 no.3
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• pp.252-272
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• 2003

The view mechanism provides users with appropriate portions of database through data filtering and integration. In the Web era where information proliferates, the view concept is also useful for XML, a future standard for data exchange on the Web. This paper proposes a method of implementing XML views called XML view indexing, whereby XML view xv is represented as an XML view index(XVI) which is a structure containing the identifiers of xv's underlying XML elements as well as the information on xv. Since XVI for xv stores just the identifiers of the XML elements but not the elements themselves, when a user requests to retrieve xv, its XVI should be materialized against xv's underlying XML documents. Also an efficient algorithm to incrementally maintain consistency of XVI given a update of xv's underlying XML documents is required. This paper proposes and implements data structures and algorithms for XML view indexing. The performance experiments on XML view indexing reveal that it outperforms view recomputation for repeated accesses to the view, and requires as much as about 30 times less storage space compared to XML view materialization though the latter takes less time for repeated accesses to the view due to no need of materialization.

• The Journal of Fisheries Business Administration
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• v.16 no.2
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• pp.1-18
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• 1985

The dispute on the object of study in the business management have been carried out since 1912 in Germany, and then it is the situation of "business management" academic world there is no the confirmed object. But P. F. Drucker has prescribed the large enterprise as the object of his study of management, because the large enterprise it the decisive, the representative, and constitutive in modern industrial country. And it is usual that we would consider the large manufacturing enterprise as the object of study. But, in fisheries management, because large fisheries enterprises are almost attached too much to the pelagic fisheries, it is judged that they are not "decisive". And it is judged that they are not "representative", because the large fisheries enterprises can not sufficiently symbolize the managerial characteristic of fisheries industry. The coastal and inshore fisheries which constitute th real part of fishing industry have been operating by private enterprises which are small business in scale, so the large fisheries enterprises could not be considered "constitutive " Therefore, the private fisheries enterprises is "decisive" because it is distributed in all most fisheries management, "representative" because it is exceedingly symbolize the managerial characteristic of fishing industry, and constitutive because it constitute the real part of fisheries industry. From the above-mentioned, it could be concluded that the object of study is regarded the private fisheries enterprise as appropriate as long as it is engaging in producing fisheries product as good and conducts the pursuit of principle of profit maximization. Because the object of study can not include all the thing which has to be observed in order to study, the materialization of the object is actually necessary. And then as aforesaid we intend to realize the materialization through taking the private fisheries enterprise as the object in fisheries management theory. And the materialization does mean a necessary process in choosing the object of analysis, but not the entity itself.choosing the object of analysis, but not the entity itself.