• Journal of Korea Multimedia Society
• /
• v.14 no.5
• /
• pp.691-702
• /
• 2011

Recently, several researchers have attempted to combine human visual perception and computer graphics. Cole et. al. suggest the study results in which line drawing algorithm in computer graphics characterize the properties of line drawing made by artists. The paper also evaluates CG line drawing algorithms depending on whether people recognize effectively specific 3D shape from the image made by those CG line drawing algorithms. However, human recognizes the shape of objects more effectively in image made by BRDF shading model than line drawing algorithm. It means that the shading factor is important to recognize shape with human perception. In this paper, we analyze the correlation between shading made by human artists and that made by CG shading algorithms. The study is to characterize the mathematical properties of artists' shading and CG shading. This type of analysis can guide the future development of new CG shading algorithm in computer graphics for the purpose of shape perception.

• Journal of architectural history
• /
• v.7 no.3 s.16
• /
• pp.107-120
• /
• 1998

Even though Gothic architecture, one of the most technologically complex sophisticated structural systems, has been interpreted by art and architectural historians since the nineteenth century, we still cannot entirely comprehend either the medieval builder's constructional technique and structural knowledge or the meaning of Gothic architectural elements. The major reason is that contemporaneous written documentation concerning design methods and constructional techniques of medieval architecture is lacking. In 1955, the Bibliotheque Nationale in Paris exhibited the sketchbook of the thirteenth century architect Villard do Honnecourt. After the exhibition, analysis on the architectural drawings of Villard's sketchbook had reported widely. Most of analysis on Villard, however, has been on his drawing and artistic style, and there has been very little published analysis of his profession and question on the author of the sketchbook. Thus, the purpose of this study is to investigate the characteristics of the sketchbook and identify the artist who drew it. The sketchbook poses a number of unsolved questions. There is no doubt that several hands have contributed some drawing with appropriate captions, particularly in the section devoted to the application of practical geometry to problems of masonry and carpentry. Scholars have assumed and revealed that it was not made by only one person, and it dealt too many different fields and styles. Through this study, the sketchbook drawings consist of five different styles and person (original painter, master1, master2, master3, and the last owner), and they, not Villard, just redrew the original drawings and bound the sketchbook. Therefore, Villard de Honnecourt was just a mentor of the sketchbook and he did not participate any writing and drawing in the sketchbook.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.7
• /
• pp.2246-2256
• /
• 1996

To investigate the effect of material and precess variables on stamping formability of sheet materials, simulations for the cup drawing and the Yoshida buckling test were carried out using ABAQUS, commercial nonlinear finite element analysis code. The various factor effects on stamping formability of sheet materials were analyzed by the designed process according to Taguch's orthogonal array experiment. Cup drawing simulation showed that local neckling was very sensitive to plastic anisotropy parameter of sheet material and friction coefficient between sheet and tool interface. Simulations for the Yoshida buckling test have clarified that buckling behaviour of sheet material was mostly susceptible to yield stress and sheet thickness mostly. However, plastic anisotropy parameter and strain hardening coefficient affect moderately buckling behaviour of steel sheets after the buckling initiation.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2000.10a
• /
• pp.124-127
• /
• 2000

The finite element analyses of the wrinkling initiation and growth in the sheet metal forming process provide the detailed information about the wrinkling behavior of sheet metal. The direct analyses of the wrinkling initiation and growth, however, bring about a little difficulty in complex industrial problems because it needs large memory size and long computation time. For the description of wrinkling growth, the mesh elements should be sufficiently small and the size of finite element matrix becomes large. In the static implicit finite element method therefore, the direct analysis of wrinkling growth in a complex sheet metal forming process is rather difficult. From the industrial viewpoint of tooling design, the readily available information of possibility and location of wrinkling is sometimes more preferable to the detailed time-consuming information. In the present study, therefore, the wrinkling factor that shows locations and relative possibility of wrinkling initiation is proposed as a convenient tool of relative wrinkling estimation based on the energy criterion. The location and relative possibility of wrinkling initiation are predicted by calculating the wrinkling factor in various sheet metal forming processes such as cylindrical cup deep drawing, spherical cup deep drawing, and elliptical cup deep drawing. The wrinkling factor is also implemented in the analysis of the door inner stamping process to predict wrinkling.

• Transactions of Materials Processing
• /
• v.15 no.3 s.84
• /
• pp.232-240
• /
• 2006

Magnesium alloys are expected to be widely used fur the parts of structural and electronic appliances due to their lightweight and EMI shielding characteristics. While the die casting has been mainly used to manufacture the parts from the magnesium alloys, the press forming is considered as an alternative to the die casting for saving the manufacturing cost and improving the structural strength of the magnesium alloy parts. However, the magnesium alloy has low formability at room temperature and therefore, in many cases, forming at elevated temperatures is necessary to obtain the required material flow without failure. In the present study, square cup deep drawing tests using the magnesium alloy AZ31 sheet were experimentally conducted at various elevated temperatures as well as room temperature, and the corresponding finite-element simulations, which calculated the damage evolution based on the Oyane's criterion, were conducted using the stress-strain relations from the tensile tests at various temperatures. The formability predictability by the finite-element analysis was investigated by comparing the predicted damage distributions over the deformed AZ31 sheet at elevated temperatures with the corresponding experimental deformations with failures.

• Journal of Families and Better Life
• /
• v.28 no.6
• /
• pp.1-18
• /
• 2010

The purpose of this study is to develop and verify the effectiveness of a group art therapy program to help children from multicultural families adapt to school life by using Kinetic School Drawing(KSD). The result of this study showed that the group art therapy program of the multicultural family's children may have a positive effect in aiding their school life adaptation. The results showed considerable and statistical outcome in the fore and after drawing inspection of the dynamic KSD. Also, the size of the self-image became bigger and their expressions has been increased. The qualitative analysis also showed a huge change in dynamistic personal relationships due to the relationship with their peers with the same aged and the tutor. This study emphasizes the importance of the group art therapy program to be applied before children are admitted to school because of growing recognition of concern about the maladjustment of rapidly growing multicultural family's children. It is also suggests that the group art therapy program of growing multicultural family's children should be viewed with an ecological point of view.

• Korean Journal of Metals and Materials
• /
• v.50 no.7
• /
• pp.511-516
• /
• 2012

Low temperature ${\delta}$-precipitation phenomenon below 2-step aging ($718^{\circ}C$, $8hr+621^{\circ}C$, 8 hr) temperature of cold drawn Inconel 718 alloy wire was investigated. The investigation was carried out on wires with a cold drawn ratio of 0, 20, 50 and 70% using OM, SEM, XRD, TEM, and DSC. In microstructures of 50 and 70% drawn wire, many precipitates were found along the grain boundaries and the twin boundaries in deformation band. From the results of the XRD and TEM analysis, the precipitates were identified as plate-like ${\delta}$-phase. From the results of the DSC analysis, it was also found that a temperature of ${\delta}$-precipitation decreases with an increase of the cold drawn ratio. We concluded that cold drawing of inconel 718 wire promotes the ${\delta}$-precipitation, and under the condition of a high drawing ratio, the ${\delta}$-phase could be precipitated at a temperature below the aging temperature ($718^{\circ}C$).

• Korean Journal of Schizophrenia Research
• /
• v.23 no.1
• /
• pp.15-28
• /
• 2020

Objectives: This study investigated the relationship between clock-drawing test (CDT) performance and neuropsychological functions in patients with chronic schizophrenia. Methods: Thirty-one patients with schizophrenia and 30 healthy controls participated in this study. The CDT was administered in three conditions and analyzed using both quantitative and qualitative scoring systems. Comprehensive neuropsychological tests were administered. Results: The results of the quantitative analysis showed that the schizophrenia group performed significantly worse in all three conditions of the CDT compared with the control group. However, no significant differences were observed between the two groups, when the IQ and educational level were controlled. The qualitative analysis showed that the schizophrenia group exhibited significantly more errors in "graphic difficulty" compared with the control group. In addition, CDT quantitative scores were significantly correlated with visuospatial function, memory, attention and executive functions in patients with schizophrenia. Conversely, each qualitative error type was correlated with specific cognitive domains. Furthermore, "graphic difficulty" and "spatial/planning deficit" were identified as predictors of depression symptoms in patients with schizophrenia. Conclusion: The present study demonstrated that the CDT is useful for assessing cognitive dysfunctions in patients with schizophrenia, while qualitative analyses provide more specific information about cognitive deficits compared with quantitative analyses.

• Transactions of Materials Processing
• /
• v.21 no.1
• /
• pp.49-57
• /
• 2012

It is difficult to estimate the properties of multilayered sheet because they are composed of one or more different materials. Plastic deformation behavior of the multilayered sheet is quite different as compared to each material individually. The deformation behavior of multilayered sheet should be investigated in order to prevent forming defects and to predict the properties of the formed part. In this study, the mechanical properties and formability of stainless steel-aluminum-magnesium multilayered sheet were investigated. The multilayered sheet needs to be deformed at an elevated temperature because of its poor formability at room temperature. Uniaxial tensile tests were performed at various temperatures and strain rates. Fracture patterns changed mainly at a temperature of $200^{\circ}C$. Uniform and total elongation of multilayered sheet increased to values greater than those of each material when deformed at $250^{\circ}C$. The limiting drawing ratio (LDR) was obtained using a circular cup deep drawing test to measure the formability of the multilayered sheet. A maximum value for the LDR of about 2 was achieved at $250^{\circ}C$, which is the appropriate forming temperature for the Mg alloy. Fracture patterns on a circular cup and thickness of formed part were predicted by a rigid-viscoplastic FEM analysis. Two kinds of modeling techniques were used to simulate deep drawing process of multilayered sheet. A single-layer FE-model, which combines the three different layers into a macroscopic single layer, predicted well the thickness distribution of the drawn cup. In contrast, the location and the time of fracture were estimated better with a multi-layer FE model, which used different material properties for each of the three layers.

• Journal of Korea Society of Industrial Information Systems
• /
• v.27 no.1
• /
• pp.1-9
• /
• 2022

The goal of this paper is to create a deep learning model based on triplet loss for generating similar child drawing selection algorithms. To assess the similarity of children's drawings, the distance between feature vectors belonging to the same class should be close, and the distance between feature vectors belonging to different classes should be greater. Therefore, a similar child drawing selection algorithm was developed in this study by building a deep learning model combining Triplet Loss and residual network(ResNet), which has an advantage in measuring image similarity regardless of the number of classes. Finally, using this model's similar child drawing selection algorithm, the similarity between the target child drawing and the other drawings can be measured and drawings with a high similarity can be chosen.