• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.142-146
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• 2010

This study presents the design of small size turbo-compressor to increase the performance using computational fluid analysis. A three dimensional computation was conducted changing the main parameters of impeller blade and diffuser shape, respectively, and the design was performed on a basis analysis of result of that. As a result, the Improved shapes show the increase of efficiency in comparison with the existing shape. This study will be used as useful reference data to establish the design concept of the small size turbo-compressor and to improve its performance.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.670-674
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• 1996

In automated search of a design database to support mechanical design, it is necessaryto recognize a shape pattern which represents a design object. This paper introduces the concept of a surface relation graph (SRG) for recognizing shape patterns from a 3D boundary representation scheme of a solid model(a B-rep model). In SRG, the nodes and arcs correspond to the faces and edges shared by two adjacent faces, respectively. An attribute assigned to an arc is given by an integer which discriminates the relationship between two adjacent faces. The + sign of the integer represents the geometric convexity of the solid, and the -sign the concivity at the shared edge. The input shape is recognized by comparison with the predefined features which are subgraphs of the SRG. A hierarchyof the database for upporting the design is presented. A search for the design database is also discussed. The usefulness of this method is illustrated by some application results.

• 한국정밀공학회지
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• 제11권1호
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• pp.201-210
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• 1994

A theoretical heat-flow model incorporating with a constant moving CO$_{2}$ laser beam has been analyzed to predict depth and the shape of bead section during last beam welding. The laser beam is exponentially attenuated with an abosrption coefficient in the material. The solution can be expressed in terms of normalized variables. The experimental data were generated by usint CW 2 CO$_{2}$ laser with multi beam mode and CW 3 kW CO$_{2}$laser with Gaussian mode. The specimens were made as bead-on-plate welds for SM 10C, STS 304, STS 316, STS 420 and pure Nickel. The maximum possible penetration depth and the shape of beas section for given sources of laser power, travel speed and beam spot size can be prdicted with this model in a given material.

• 산업경영시스템학회지
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• 제23권61호
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• pp.1-11
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• 2000

Ergonomic vehicle design is very important for driver's safety and sensibility. Many studies have emphasized the physical factors of human operator and usability of control devices. However, driver's cognitive factors such as the shape of cognitive map have not been well documented. The aim of this research is to find the relationship between the shape of Instrument Pane (IP) in driver's cognitive map and the real vehicle. To do this, Sketch Map Method (SMM), that is an extraction method of cognitive map, was employed to extract the shape of middle-aged driver's cognitive map. In this study, SMM was modified to formulate driver's cognitive map because this process is not being in the existing SMM. Next, correlation was analyzed between individual cognitive map and the shape of real vehicle's IP. The result showed that the position of volume control switch and cigar jack was similar between these but the position of others wasn't.

• 한국가구학회지
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• 제20권2호
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• pp.122-135
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• 2009

The objective of this work was to research click profile of laminate flooring by comparison of click and bonding laminate floorings, especially base on the click profile shape, bonding strength and international patents. Non-glue locking system has been used since laminate flooring was developed. For the reason of environment and saving installation time, the manufacturer in Europe and USA has developed click profile for laminate flooring. Each manufacturer has patent on each click profile. Although each click profile has good lock strength as shape, Berryand Unilin company's click profile systems showed higher locking strength than others. Korean laminate flooring company pay the fee of patent for using European and American manufacturer's click profile. From this work, we grope Korean style laminate flooring and click profile through research on the click profile shape, bonding strength and patents of European and American manufacturers.

• 응용통계연구
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• 제21권6호
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• pp.1109-1116
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• 2008

Biplots are the multivariate analogue of scatter plots. They are useful for giving a graphical description of the data matrix, for detecting patterns and for displaying results found by more formal methods of analysis. Nevertheless, when some values are missing in data matrix, most biplots are not directly applicable. In particular, we are interested in the shape variability of principal component biplot which is the most popular in biplots with missing values. For this, we estimate the missing data using the EM algorithm and mean imputation according to missing rates. Even though we estimate missing values of biplot of incomplete data, we have different shapes of biplots according to the imputation methods and missing rates. Therefore we propose a RMS(root mean square) for measuring and comparing the shape variability between the original biplots and the estimated biplots.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1998년도 동계 학술대회 논문집
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• pp.144-149
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• 1998

• Smart Structures and Systems
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• 제16권5호
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• pp.891-918
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• 2015

In many of microdevices a part of a microbeam is covered by a piezoelectric layer. Depend on the application a DC or AC voltage is applied between upper and lower side of the piezoelectric layer. A common method in many of previous works for evaluating the response of these structures is discretizing by Galerkin method. In these works often single mode shape of a uniform microbeam i.e. the microbeam without piezoelectric layer has been used as comparison function, and so the convergence of the solution has not been verified. In this paper the Galerkin method is used for discretization, and a comprehensive analysis on the convergence of solution of equation that is discretized using this comparison function is studied for both clamped-clamped and clamped-free microbeams. The static and dynamic solution resulted from Galerkin method is compared to the modal expansion solution. In addition the static solution is compared to an exact solution. It is denoted that the required numbers of uniform microbeam mode shapes for convergence of static solution due to DC voltage depends on the position and thickness of deposited piezoelectric layer. It is shown that when the clamped-clamped microbeam is coated symmetrically by piezoelectric layer, then the convergence for static solution may be obtained using only first mode. This result is valid for clamped-free case when it is covered by piezoelectric layer from left clamped side to the right. It is shown that when voltage is AC then the number of required uniform microbeam shape mode for convergence is much more than the number of required mode in modal expansion due to the dynamic effect of piezoelectric layer. This difference increases by increasing the piezoelectric thickness, the closeness of the excitation frequency to natural frequency and decreasing the damping coefficient. This condition is often indefeasible in microresonator system. It is concluded that discreitizing the equation of motion using one mode shape of uniform microbeam as comparison function in many of previous works causes considerable errors.

• 대한가정학회지
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• 제34권2호
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• pp.43-55
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• 1996

The purpose of this study was to investigate the slacks pattern making on the movement-fitness of the knee region. The experimental items were divided into the lower limb movement (M1~M5) and slacks pattern designs (4 : basic pattern, in-pleats, side-pleats, seam-line increase). This study was done by clothing pressure test, sensory evaluation test and the difference shape-transformation of wearing-slacks. The summarized finding resulted from experiments and investigation are suggested as follows ; First, the clothing pressure test showed that the order of clothing pressure in the movement was the rabbit leap movement (M3), the sit on knees (M4), the nobleman sitting (M5), the sit on chair (M2) from the highest to the lowest. In the comparison of clothing pressure tested by blocks of lower-limb, center front knee region shows the highest of 300g/cm2. In it by constructional methods, the clothing pressure of in-pleats, side-pleats methods shows lower than basic pattern, hem-line increase methods. Also in comparison of the two methods, in-pleats method shows lower than side-pleats method. Second, by the sensory evaluation test based on the lower-limb movements and constructional methods of slacks, it was found that the functional factor score of the rabbit leap movement was also the waist, hip, knee region was the lowest in all blocks. And in the comparison of constructional methods, in-pleats method was the highest in all methods. Third, in consideration of the difference in the shape-transformation of wearing-slacks on the movement-fitness, pleats pattern design methods showed that the ratio of shape-transformation was lower than basic on seam-line increase methods. But the difference of the side-pleats and in-pleats methods was litle. According to these investigation, the slacks pattern making caused by movement-fitness on the knee region, in-pleats design method was the functional slacks pattern.

• Advances in concrete construction
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• 제10권1호
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• pp.61-69
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• 2020

This paper looks into how the shape of headed bars may influence the durability of reinforced concrete structures. Nowadays the only heads used in site works are cylindrical in shape. An alternative shape of head is studied in this piece of work. The new head reduces the concentration of stresses and so the appearance of cracks. In this work durability is studied based on both, first cracking and failure mode. An experimental campaign of 12 specimens and finite element modelling are described. The specimens were subjected to an accelerated corrosion process using an electrical current supply. Direct current was impressed on the specimens until breaking. Test results and the results obtained from numerical models are presented. Results are presented in term of comparison between the two shapes of heads studied. It was shown that the shape of the head has a significant influence on durability of reinforced concrete structures with headed reinforcing bars.