• Journal of Korean Society for Quality Management
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• v.26 no.3
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• pp.60-70
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• 1998

When driving the expected loss generated by the quality deviation, Taguchi(1991b) assumed that an objective characteristic has the uniform distribution in its control limit. But it is reasonable to assume that an objective characteristic has the normal distribution than the uniform distribution. Since the triangular distribution is similar to the normal distribution and easy to handle as well, in this article, we first find the optimum measurement interval and the optimum control limit under the triangular distribution. Under the normal assumption, the modified method is compared to Taguchi's. Secondly we find the numerical value solution of the optimum measurement interval and the optimum control limit under the normal distribution.

• Journal of applied mathematics & informatics
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• v.41 no.2
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• pp.311-320
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• 2023

In this article, a new penalty and different ranking algorithms are used to find the lowest transportation costs for the fuzzy transportation problem. This approach utilises different ranking techniques when dealing with triangular fuzzy numbers. Also, we find that the fuzzy transportation solution of the proposed method is the same as the Fuzzy Modified Distribution Method (FMODI) solution. Finally, examples are used to show how a problem is solved.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.35 no.11
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• pp.479-486
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• 1986

It is necessary to consider a rotor movement in dynamic analysis on the flux distribution of electric machinery by FEM. Therefore, if air-gap domain was subdivided into triangular elements, computation results contain errors due to variation of element shape in air-gap because the nodal points corresponding to the rotor are displaced in analyzing domain for the time difference. In order to reduce this errors, the paper presents a application of a Macro Air-gap Element that interpolation function is obtained analytically and a means to join it with linear triangular elements in the rotating machine or in the linear machine. At the end of paper, setting up analytic domain model, it compares analytic solution with the computation results of Macro Air-gap Element appliction and that of linear triangular element subdivision only to each cases of nodal displacement. And it carries out that errors due to variation of element shape are reduced effectively by application of a Macro air-gap element.

• Korean Journal of Computational Design and Engineering
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• v.5 no.1
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• pp.95-101
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• 2000

For last two decades numerous automatic mesh generation algorithms for various two dimensional objects have been introduced continuously and among them triangular mesh generation schemes have been majority because of efficiency and controllability. In our study, an existing triangular mesh generation algorithm developed by Lo is totally modified to more improve node distribution, element shape, and objects shape independency. ft is composed of node generation part and element generation part. In order to find a suitable node position within geometry, the suggested algorithm searches desirable positions of points within boundary and optimizes node position to generate comparatively well-shaped elements. More over, the suggested algorithm handles various complex two dimensional objects and its meshing speed shows superiority to those of the existing triangulation mesh generation algorithms. It is fully automated in a sense of constructing object boundary and hence can be directly used as an independent meshing software.

• Journal of Biosystems Engineering
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• v.13 no.4
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• pp.9-19
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• 1988

The threshing of head-feed combine may be accomplished mainly by the action of impact between threshing teeth and rice. In this study, it was attempted to assess threshing performance characteristics of head-feed threshing teeth. And the characteristics of threshing teeth will be applied to the method which could analyze the time and order of impact between teeth and the rice, which was used as a basis for predicting the threshing performance and determining the optimum design parameters. The results of the study are summarized as follows: 1. About 50% of threshed material were threshed by the beginning 7 impacts on the rice bundle. Threshing torque decreased until 25 impacts and did not change thereafter. 2. There was significant difference in the threshability according to the shape of threshing teeth. The triangular-shaped tooth was the most efficient in threshability ratio and the semicircle-shaped tooth was the lowest. There was no significant difference in specific energy requirement for the varied teeth design. Torn-head ratio being generated by the semicircle-shaped and the triangular-shaped teeth in series was less than that by a single tooth with the triangular-shaped and the double setting of the triangular-shaped. Chaff generation ratio by the triangular-shaped and the semicircle-shaped teeth was less than the others tried. 3. The triangular-shaped teeth in series, which was newly designed for this study, showed an intermediate characteristics between the double setting of the triangular-shaped and the semicircle- shaped teeth. Threshability ratio of the triangular-shaped teeth in series was higher than that of the semicircle and lower than the double setting of the triangular-shaped tooth. Torn-head generation ratio for it was about same as that of the semicircle. Chaff being generated by the triangular-shaped teeth in series was about same as the double setting of the triangular-shaped teeth. 4. About 40% of threshed grains which passed through concave were concentrated under the threshing tooth and the rest of grains displayed a skew distribution toward the inlet of threshing chamber.

• Journal of the Society of Naval Architects of Korea
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• v.57 no.2
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• pp.114-123
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• 2020

A high-order potential-based panel method based on Green's theorem, with piecewise-linear dipole strength on triangular panels, is formulated for the analysis of potential flow around a three-dimensional wing. Previous low-order panel methods adopt square panels with piecewise-constant dipole strength, which results in inherent errors. Square panels can not represent a high curvature lifting body, such as propellers, since the four vertices of the square panel do not locate at the same flat plane. Moreover the piecewise-constant dipole strength induces inevitable errors due to the steps in dipole strength between adjacent panels. In this paper a high-order panel method is formulated to improve accuracy by adopting a piecewise linear dipole strength on triangular panels. Firstly, the square panels are replaced by triangular panels in order to increase the geometric accuracy in representing the shape of the object with large curvature. Next, the step difference of the dipole strength between adjacent panels is removed by adopting piecewise-linear dipole strength on the triangular panels. The calculated results by the present method is compared with analytical ones for simple non-lifting geometries, such as ellipsoid. The results for an elliptic wing with zero thickness at finite angle of attack are compared with Jordan's results. The comparison shows reasonable agrements for the both lifting and non-lifting bodies.

• Korean Journal of Computational Design and Engineering
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• v.10 no.3
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• pp.168-178
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• 2005

The Delaunay triangular net is primarily characterized by a balance of the whole by improving divided triangular patches into a regular triangle, which closely resembles an equiangular triangle. A triangular net occurring in certain, point-clustered, data is unique and can always create the same triangular net. Due to such unique characteristics, Delaunay triangulation is used in various fields., such as shape reconstruction, solid modeling and volume rendering. There are many algorithms available for Delaunay triangulation but, efficient sequential algorithms are rare. When these grids involve a set of points whose distribution are not well proportioned, the execution speed becomes slower than in a well-proportioned grid. In order to make up for this weakness, the ids are divided into sub-grids when the sets are integrated inside the grid. A method for finding a mate in an incremental construction algorithm is to first search the area with a higher possibility of forming a regular triangular net, while the existing method is to find a set of points inside the grid that includes the circumscribed sphere, increasing the radius of the circumscribed sphere to a certain extent. Therefore, due to its more efficient searching performance, it takes a shorer time to form a triangular net than general incremental algorithms.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.6
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• pp.42-48
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• 1998

This paper is concerned with the heat flux distribution and energy partition for creep-feed grinding. From measurements of transient grinding temperatures in the workpiece sub-surface using an embedded thermocouple, the overall energy partition to the workpiece was estimated from moving heat source theory for a triangular heat flux distribution as 3.0% for down grinding and 4.5% for up grinding. The higher energy partition for up grinding can be attribute to the need to satisfy thermal compatibility at the grinding zone. The influence of cooling outside the grinding zone can be analytically taken into account by specifying convective heat transfer coefficients on the workpiece surface ha ahead of the heat source (grinding zone) and hb behind the heat source. The smaller energy partition together with slightly lower grinding power favors down grinding over up grinding.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.4
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• pp.373-378
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• 2002

This paper presents the results of an electromagnetic field uniformity of a triangular reverberation chamber that can be used alternatively for analysis and measurement of electromagnetic interference and immunity test. Equilateral triangular reverberation chamber and Schroeder diffusers were designed and fabricated for this purpose. FDTD simulation method was applied to analyze the field distribution inside of two different types of reverberation chambers. As a result, the electromagnetic field uniformity was improved inside of triangular reverberation chambers, and the measured field uniformity was improved by 1 ∼4 ㏈ compared to the ones without diffusers.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.2
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• pp.212-217
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• 2012

A fuzzy set $A$ defined on a probability space ${\Omega}$, $\mathfrak{F}$, $P$ is called a fuzzy event. Zadeh defines the probability of the fuzzy event $A$ using the probability $P$. We define the generalized triangular fuzzy set and apply the extended algebraic operations to these fuzzy sets. A generalized triangular fuzzy set is symmetric and may not have value 1. For two generalized triangular fuzzy sets $A$ and $B$, $A(+)B$ and $A(-)B$ become generalized trapezoidal fuzzy sets, but $A({\cdot})B$ and $A(/)B$ need not to be a generalized triangular fuzzy set or a generalized trapezoidal fuzzy set. We define the normal fuzzy probability on $\mathbb{R}$ using the normal distribution. And we calculate the normal fuzzy probability for generalized triangular fuzzy sets.