• Journal of the Korea Furniture Society
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• v.26 no.1
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• pp.1-11
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• 2015

This study shows how the plastic furniture design has developed in general and by contemporary auteurist designers. Plastic furniture design began with Mies van der Rohe's chairs produced with compression moldings, and was later successfully commercialized by Knoll and Herman Miller. Plastic undoubtedly played a significant role in giving modern furniture design its current status with its suitability for efficient mass-production. However, the expectations consumers have for designers have extended by the widespread internet accessibility along with the higher standards of the well-developed design industry, and now mass-production is no more the only key to appealing to those in need. Based on the information gathered from the process above, analyses were done on the works of various design artists in the current industry, which leads to certain suggestions that would help bring the plastic furniture design to the next level as a whole.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.603-608
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• 2008

It is well known that the topology optimization for plastic problem is not easy since the iterative analyses to evaluate the objective and cost function with respect to the design variation are very time-consuming. The finite element limit analysis is an efficient tool which is possible to predict collapse modes and sequential collapse loads of a structure considering not only large deformation but also plastic material behavior with moderate computing cost. In this paper, the optimum topology of a structure considering large and plastic deformation is obtained using the finite element limit analysis. To verify the constructed optimization code, topology optimizations of some typical problems are performed and the optimal topologies by elastic design and plastic design are compared.

• Computers and Concrete
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• v.32 no.5
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• pp.527-541
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• 2023

This paper emphasizes the use of CFT columns in frame structures subjected to strong horizontal forces and shows that the efficiency of using CFT columns is increased when the plastic design approach is adopted. Because the plastic design approach is based on redistribution of the force of the internal member, a double node for the rotational degrees of freedom, where the adjacent two rotational degrees of freedom can be connected by a non-dimensional spring element, is designed and implemented into the formulation. In addition, an accompanying criterion is considered in order to make it possible to describe the continuous moment redistribution in members connected to a nodal point up to a complete plastic state. The efficiency of CFT columns is reviewed in comparison with RC columns in terms of the cost and the resistance capacity, as defined by a P-M interaction diagram. Three representative frame structures are considered and the obtained results show that the most efficient and economical design can be expected when the use of CFT columns is considered on the basis of the plastic design, especially when a frame structure is subjected to significant horizontal forces, as in a high-rise building.

• Structural Engineering and Mechanics
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• v.9 no.6
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• pp.569-588
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• 2000

The plastic collapse loads and their locations are predicted for a class of tapered, initially curved, and transversely corrugated cantilevered beams subjected to static tip loading. Results of both closed form and finite element solutions for several rigid perfectly plastic and elastic perfectly plastic beam models are evaluated. The governing equations are cast in nondimensional form for efficient studies of collapse load as it varies with beam geometry and the angle of the tip load. Static experiments for laboratory-scale configurations whose taper flared toward the tip, complemented the theory in that collapse occurred at points about 40% of the beams length from the fixed end. Experiments for low speed impact loading of these configurations showed that collapse occurred further from the fixed end, between the 61% and 71% points. The results may be applied to the design of safer highway guardrail terminal systems that collapse by design under vehicle impact.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.04a
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• pp.96-103
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• 2000

This research is a new design method, which will be presented as a basic concept for a more efficient minimum weight design of grillages, as an attempt to describe true collapse mechanism in as overall search as possible. It serves as introduction to the numerical technique of Linear Programming(LP) and Automatic Modified Direct Plastic Frame Analysis(AMDPFA). Attention is directed to both analysis and design, and emphasis is placed on the physical significance of Systematic Searching Techniques(SST) involved. In weight minimum grillages design, the parameterisation study in optimum beam configuration which was carried out over the range of beam sections for a given plastic section modulus likely to occur in structures by suing an adaptive stochastic optimisation technique, Genetic Algorithms.

• Archives of Plastic Surgery
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• v.51 no.1
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• pp.126-129
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• 2024

The square flap method has been successful in releasing contracture bands at various body regions. However, the original square flap method alone may not be efficient in releasing long contracture bands. We, therefore, proposed an extended design to the traditional design, which is called the "square-plus flap." A 4-year-old girl presented with a postburn web-like contracture band over the right axilla. We marked a square flap technique at the center of the contracture band and then two additional Z-plasties were placed on both edges of the flap. After the release and securing of the square flap, the adjacent distal Z-plasty was then transposed and sutured in their new locations. We do not need to incise the proximal Z-plasty as we could achieve complete relaxation of the contracture band. This novel modification can be added to the plastic surgeon's armamentarium for releasing long postburn contracture bands involving distinct body regions.

• Journal of Korean Society of Steel Construction
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• v.14 no.1
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• pp.13-21
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• 2002

In this paper, 3-D frame design using refined plastic-hinge analysis accounting for local buckling is developed. This analysis accounts for material and geometric nonlinearities of the structural system and its component members. Moreover, the problem associated with conventional refined plastic-hinge analyses, which do not consider the degradation of the flexural strength caused by local buckling, is overcome. Efficient ways of assessing steel frame behavior including gradual yielding associated with residual stresses and flexure, second-order effect, and geometric imperfections are presented. In this study, a model consisting of the width-thickness ratio is used to account for local buckling. The proposed analysis is verified by the comparison of the LRFD results. A case study shows that local buckling is a very crucial element to be considered in second-order plastic-hinge analysis. The proposed analysis is shown to be an efficient, reliable tool ready to be implemented into design practice.

• Proceeding of KASS Symposium
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• 2006.05a
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• pp.165-169
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• 2006

This study presents a new stress analysis method to be substituted for the elastic analysis in such a plastic design procedure. This method is accompanied by an efficient mathematical tool which can be easily handled by personal computer. The method also easily accepts arbitrary strategies by the designer for selection member size.

• Structural Engineering and Mechanics
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• v.1 no.1
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• pp.31-46
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• 1993

The motivations of the application of shakedown analysis to the earthquake-resistant design of ductile moment-resisting steel structures are presented. The problems which must be solved with this application are also addressed. The illustrative results from a series of static and time history nonlinear analyses of one-bay three-story steel frame and the related discussions have shown that the incremental collapse may be the critical design criterion in case of earthquake loading. Based on the findings, it was concluded that the inelastic excursion mechanism for alternation load pattern, such as in earthquake, should be the sidesway mechanism of the whole structure for the efficient mobilization of the structural energy dissipating capacity and that the shakedown analysis technique can be used as a tool to ensure this mechanism.

• Ocean Systems Engineering
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• v.13 no.4
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• pp.367-384
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• 2023

Herein, we present the design and development of an efficient finite element analysis model for thermal plate forming in shipbuilding. Double curvature shells in the ship building industries are primarily formed through the thermal forming technique. Thermal forming involves heating of steel plates using heat sources like oxy-acetylene gas torch, laser, and induction heating, etc. The differential expansion and contraction across the plate thickness cause plastic deformation and bending of plates. Thermal forming is a complex forming technique as the plastic deformation and bending depends on many factors such as peak temperature, heating and cooling rate, depth of heated zone and many other secondary factors. In this work, we develop an efficient finite element analysis model for the thermo-mechanical analysis of thermal forming. Different simulations are reported to study the effect of various parameters affecting the process. Temperature dependent properties are used in the analysis and the finite element analysis model is used to identify the critical flame velocity to avoid recrystallization of plate material. A spring connected plate is modeled for structural analysis using spring elements and that helps in identifying the resultant shapes of various thermal forming patterns. Finally, detailed simulation results are reported to establish the efficacy, applicability and efficiency of the designed and developed finite element analysis model.