• Journal of Korean Institute of Industrial Engineers
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• v.23 no.4
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• pp.687-698
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• 1997

In this paper, a Variation of Blast with Go-Back-N(V-BGBN) protocol is proposed, which differs from Blast with Go-Back-N(BGBN) and Blast with Full Retransmission on Error(BFRE) protocols in the retransmission strategy of packets. Performances of these three protocols under correlated packet errors are analyzed. Throughput efficiency of an arbitrary packet is obtained under the assumption that the round trip delay and the packet length are respectively constant. Recursive formula and difference equations are used as analytical tools. Correlation of packet errors is modelled by a two state Markov chain. The throughput efficiencies under these protocols are compared. V-BGBN protocol is shown to be superior to other two protocols in high speed network.

• Proceedings of the KIEE Conference
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• 2003.10b
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• pp.119-121
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• 2003

The magnetic bearing is an important element for high-speed system, such as semiconductor equipment and machine tools. Particularly, The homopolar magnetic bearing has the advantages of lower power losses, more space for heat dissipation and coil winding. This paper deals with analysis and comparison of the homopolar magnetic bearing according to four different PM structures. On the basis of these results, we find one homopolar magnetic bearing superior to the others. finally, this paper derive force characteristic equation for this model and deals with comparison of between analytical and FE results.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.22 no.4
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• pp.753-761
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• 1998

The determination of sound pressure radiated from periodic plate structures is fundamental in the estimation of noise level in aircraft fuselages or ship hull structures. As a robust approach to this problem, here a very general and comprehensive analytical model is developed for predicting the sound radiated by a vibrating plate stiffened by periodically spaced orthogonal unsymmetrical beams subjected to a sinusoidally time varying point load. The plate is assumed to be infinite in extent, and the beams are considered to exert both line force and moment reactions on it. Using this theoretical model, the sound pressure levels on axis in a semi-infinited fluid (water) bounded by the plate were calculated using three numerical tools such as the Gauss-Jordan method, the LU decomposition method and the IMSL numberial package. Especially, the variation in the sound pressure levels and their modes were investigated according to the change in frequency, bay spacing and bay distance.

• The Journal of the Korean dental association
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• v.54 no.11
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• pp.908-916
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• 2016

Psychological and cognitive development in child and adolescent periods is key knowledge for understanding children and adolescents' behavior and inducing their actions. So far, psychoanalytic approaches have been primarily researched by Freud's analytical tools and Piaget's analysis on cognitive developments have been mainly employed to explore children and adolescents' psychological developments. In addition, other various theories have been suggested in order to explain children and adolescents' psychological developments. However, in reality, it is difficult to integrate diverse theoretical lens to investigate children and adolescents' psychological developments. Considering this constraint, in clinical dentistry, the conventional theoretical instruments have been still widely employed to guide children and adolescents' behavior.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.3
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• pp.380-387
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• 2013

In this study, two finite element (FE) models were developed to evaluate the thermal characteristics of a feeding axis of a CNC lathe. One was used for analysis of heat transfer to identify the temperature distribution of the feeding axis and then, the other was used for analysis of thermal deformation to evaluate its structural behavior based on the temperature distribution. The FE models were based on the test standard for the axial thermal displacement. The feeding velocity was composed of three steps: the ascending, constant, and descending velocities. Therefore, the heat generation and convection coefficient were calculated for each velocity and applied to the thermal FE model. The convection coefficient for the ball screw rotation was based on an experimental equation. The result of the analytical thermal displacement was compared with that of the experimental displacement to verify the finite element models.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.8
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• pp.1461-1471
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• 2002

Linear motor has a lot of advantages in comparison with conventional feed mechanisms: high velocity, high acceleration, good positioning accuracy and a long lifetime. An important disadvantage of linear motor is its high power loss and heating up of motor and neighboring machine components in operation. For the application of the linear motors to precision machine tools an effective cooling method and thermal optimizing measures are required. In this paper Finite-Element-Method for the thermal behavior of synchronous linear motor is introduced, which is useful for the design and manufacturing of linear motors. By modeling the linear motor the orthotropic physical properties of the sheet metal and windings were considered and convective coefficient in the water cooler and to the surroundings was defined by analytical and experimental method. The calculated isothermal lines could analyze the heat flow in the linear motor.

• Journal of Korean Society of Rural Planning
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• v.16 no.3
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• pp.67-76
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• 2010

The objective of this study is to investigate a priority and selection of agricultural specialization items from Daegu and Gyeongbuk region by using analytical tools such as, the Analytic Hierarchy Process(AHP) and the Scoring Method. The results of this study are as follows; 1) Five major items were selected for each region based on Daegu and Gyeongbuk regional agricultural performances. 2) The results of AHP analysis, Daegu and Gyeongbuk's agricultural experts evaluated the weight of three decision-elements(objectiveness 0.35, efficiency 0.341, identity 0.309) and seven decision-elements. 3) Results of AHP and Scoring Method analysis, Investigated a priority of agricultural specialization 3 items in 25 cities and districts Daegu and Gyeongbuk regional agricultural performances. 4) Finally, The results of this study will provide basic information on agricultural specialization policy in Daegu and Gyeongbuk region.

• Journal of the Korean Data and Information Science Society
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• v.17 no.4
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• pp.1161-1167
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• 2006

Since microarray data structures are various and complicative, the data are generally stored in databases for approaching to and controlling the data effectively. But we have some difficulties to analyze and control the data when the data are stored in the several database management systems. The existing analysis tools for DNA microarray data have many difficult problems by complicated instructions, and dependency on data types and operating system, and high cost, etc. In this paper, we design and implement the web-based analysis tool for obtaining to useful information from DNA microarray data. When we use this tool, we can analyze effectively DNA microarray data without special knowledge and education for data types and analytical methods.

• BMB Reports
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• v.37 no.1
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• pp.45-52
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• 2004

The goal of interaction proteomics that studies the protein-protein interactions of all expressed proteins is to understand biological processes that are strictly regulated by these interactions. The availability of entire genome sequences of many organisms and high-throughput analysis tools has led scientists to study the entire proteome (Pandey and Mann, 2000). There are various high-throughput methods for detecting protein interactions such as yeast two-hybrid approach and mass spectrometry to produce vast amounts of data that can be utilized to decipher protein functions in complicated biological networks. In this review, we discuss recent developments in analytical methods for large-scale protein interactions and the future direction of interaction proteomics.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.4
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• pp.458-464
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• 2008

The structural health monitoring has been gaining more importance in civil engineering areas such as earthquake and wind engineering. The use of health monitoring system can also provide tools for the validation of structural analytical model. However, only few structures such as historical buildings and some important long bridges have been instrumented with structural monitoring system due to high cost of installation, long and complicated installation of system wires. In this paper, the structural monitoring system based on cheap and wireless monitoring system is investigated. The use of advanced technology of micro-electro-mechanical system(MEMS) and wireless communication can reduce system cost and simplify the installation. Further the application of wireless MEMS system can provide enhanced system functionality and due to low noise densities. Identification results are compared to ones using data measured from traditional accelerometers and results indicate that the system identification using wireless MEMS system estimates system parameters accurately.