• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.1
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• pp.54-65
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• 1996

The purposes of this study were 1) to present the optimum slacks pattern for young men, 2) to develope a methodology to draft basic slacks pattern using AutoCAD The total crotch legth and the shape of the crutch line were determined by anthropometric data analysis. The total crotch length was calculated with the waist girth, the hip girth and the crotch length measurements. The anthropometric data utilized for this procedure was National Anthropometric Survey of Korea, 1992. And multidimensional anthropometric measurements were carried out for 6 male college students between the age of 18 to 24. The subjects were measured with the Martin's anthropometer and the sliding gauge. Mean, standard deviation and t-test were performed for statistical analysis of the data. The automatic drafting method was programmed by AutoLISP in AutoCAD. The automatic drafting was based on the Muller's slacks pattern drafting method, the measurements of slacks construction components and the curve of crotch line. The crotch line was drafted using of the arc function in AutoCAD. The total crotch length was calcuated using the multiple regression equation. The experimental pattern developed to accomodate individual body wleasurements expected to produce customized apparel production in QRS(Quick Response System) production system.

• Journal of Korean Society of Steel Construction
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• v.23 no.3
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• pp.327-335
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• 2011

This study has two objectives: (1) to evaluate the degradation characteristics of symmetric unbraced steel frames by using analytical approach, and (2) to suggest equation which can approximately estimate the effect of degradation during the schematic design stage. For the analytical approach, the refined plastic hinge method with an arc length algorithm was adopted. The subject of analysis was one story one-bay, multistory one-bay, and multistory three-bay unbraced steel frames. The main parameters of the analytical approach include the stiffness ratio of column to beam and the axial force ratio. The study led to the following conclusions. The normalized stiffness of degradations is affected by both stiffness ratio of column to beam and the axial load ratio; however, the major influence on degradations is the axial force ratio. The equation, which can approximately estimate the effect of degradation, was suggested together with the research results.

• KCI Concrete Journal
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• v.11 no.3
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• pp.115-126
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• 1999

An analytical method based on the nonlinear layered finite element method is developed to simulate an overall load-deflection behavior of strengthened beams. The developed model distinguishes itself by its capability to trace residual flexural behavior of a beam after the fracture of brittle strengthening materials at peak load. The model. which uses a rather advanced numerical technique for iterative convergence to equilibrium, can be regarded as superior to the two models based on load control and displacement control The model predictions were compared with the experimental results and it was observed that there was good agreement between them.

• Journal of applied mathematics & informatics
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• v.15 no.1_2
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• pp.265-275
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• 2004

In this paper, multi-objective models for designing 3D trajectory of horizontal wells are developed in a fuzzy environment. Here, the objectives of minimizing the length of the trajectory and the error of entry target point are fuzzy in nature. Some parameters, such as initial value, end value, lower bound and upper bound of the curvature radius, tool-face angle and the arc length of each curve section, are also assumed to be vague and imprecise. The impreciseness in the above objectives have been expressed by fuzzy linear membership functions and that in the above parameters by triangular fuzzy numbers. Models have been solved by the fuzzy non-linear programming method based on Zimmermann [1] and Lee and Li [2]. Models are applied to practical design of the horizontal wells. Numerical results illustrate the accuracy and efficiency of the fuzzy models.

• Journal of Korean Association for Spatial Structures
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• v.3 no.4 s.10
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• pp.85-92
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• 2003

In this work, a finite element model is presented for geometrically non-linear analysis of shell structures. Finite element by using a three-node flat triangular shell element is formulated. The non-linear incremental equilibrium equations are formulated by using an updated Lagrangian formulation and the solutions are obtained with the incremental/iterative Newton-Raphson method and arc length method. Some of results are presented for shell structures. The obtained results are in good agreement with the results available in existing literature.

• International Journal of Ocean System Engineering
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• v.2 no.3
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• pp.195-199
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• 2012

This paper reports a new analytical method to calculate the planar displacement of structures. The cross-sections were assumed to remain in plane and the deflection curve was evaluated using the curvature values geometrically, despite being solved with differential equations. The deflection curve was parameterized with the arc-length of the curvature values, and was taken as an assembly of chains of circular arcs. Fast and accurate solutions of complex deflections can be obtained easily. This paper includes a comparison of the nonlinear displacements of an elastic tapered cantilever beam with a uniform moment distribution among the proposed analytical method, numerical method of the theory and large deflection FEM solutions.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.10a
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• pp.92-95
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• 2002

A nonlinear finite element method is presented to evaluate the torsional buckling moment and failure of composite laminated cylinders. For the progressive failure analysis, the complete unloading method is used based on the maximum stress failure criteria. An arc-length method is incorporated to trace the postbuckling equilibrium path. Present finite element method is verified by the existing experimental and analytical results. The results of the parametric study show that the torsional buckling moments are sensitive to the geometric change, but are not much affected by the lay-up angle. All cylinders tested numerically show the unstable torsional buckling, and therefore the torsional buckling always leads to the catastrophic failure.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.10a
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• pp.395-402
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• 1999

This paper discusses the theoretical researches subject to elastic buckling problems of the structures. The purpose is to ensure the characteristic of buckling be true by arc-length method and the finite element method. The difficulties in processes calculating the equilibrium curve after buckling is to get the equilibrium owe near singular point at which the determinant of stiffness matrix is zero. The purpose of the load-displacement curve is to determine the buckling load of the structure, and further to get the information about the characteristic after buckling. Here, this paper expresses the incremental solution at particular point by the linear combination of both homogeneous mode and particular mode, then uses the method which gets the unknown parameter including this function, through trial-and-error method including modified N-R convergence process. Finally, this paper describes the multiple bifurcation of truss dome as the numerical examples according to this algorithm.

• Journal of the Korean Home Economics Association
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• v.37 no.7
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• pp.17-27
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• 1999

According to the design method for constructing the Korean Men's Jo-go-ri(the traditional Korean jacket)collar, there are differences in form after its completion. In the construction design of the midsection of the gusset as in that of the basic pattern Jo-go-ri, not only was the positioning of the two sides of the collar not smooth, but also, when the collar strip(Dongjung) was attached, there would be an imbalance on one side or the other so that it was difficult to achieve symmetry. Therefore in this project, by applying the pattern design of the gusset midsection to that of the collar midsection, not only did attaching the collar(Kit) and the collar strip create a visual effect by equalizing the lengths of the two sides, but the construction was also easy. This method of construction introduces the three-dimensional aspect of the human form in its conic, spherical and cylindrical aspects, so that, through schematizing the scientific character of Korea's clothing, its appropriateness is verified. As a matter of fact, since there is no standardization of pattern whether for educational use or for mass-produced clothing, so that even the patterns used in computer-assisted design are executed according to the designer's personal skill, the reality is that after completion of construction the quality has not been uniform. For this schematization, inverse calculation of measurements pertaining to the calculation formula and of teaching materials has been referenced. In particular, the partial regulation of the calculation formula pertaining to the basic pattern construction, the method of making the collar midsection, and the construction method of the extreme and mean ratio adjustment, can be adjusted for all measurements, thereby providing the establishment of a design criterion and the possibility of the standardization of construction methods. The production method for the basic pattern design is as follows: 1) The conic angle for the Jo-go-ri's girth, length end neck width is fixed at 70(72) degree. 2) The radius of the cone is sleeve length. 3) The bust girth calculation formula is B/4 + 2.5 cm. 4) The armhole formula is B/4 + 2.5cm. 5) The neck width formula is B/10. 6) The ratio of the collar junction{width of collar(Kit) + width of collar strip(Dongjung) to the gusset length is 5:8. 7) The length of the side seam is a length intersecting the armhole line and the conic radius of sleeve length, that is an arc that exceeds the length of the Jo-go-ri's midsection.

• Korean Journal of Computational Design and Engineering
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• v.15 no.3
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• pp.178-188
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• 2010

This paper addresses the problem of determining if two surfaces intersect tangentially or transversally in a mathematically consistent manner and approximating an intersection curve. When floating point arithmetic is used in the computation, due to the limited precision, it often happens that the decision for tangential and transversal intersection is not clear cut. To handle this problem, in this paper, interval arithmetic is proposed to use, which provides a mathematically consistent way for such decision. After the decision, the intersection is traced using the validated ODE solver, which runs in interval arithmetic. Then an iterative method is used for computing the accurate intersection point at a given arc-length of the intersection curve. The computed intersection points are then approximated by using a B-spline curve, which is provided as one instance of intersection curve for further geometric processing. Examples are provided to demonstrate the proposed method.