• Proceedings of the Korea Concrete Institute Conference
• /
• 1999.04a
• /
• pp.197-202
• /
• 1999

The properties of surface-glossing of exposed concrete with the kinds of form materials and form oil are investigated under various slump value. According to the experimental results, surface-glossing has high value with the increase of slump. In case of surface-glossing with the kind of the form, the form made of acryl has the best performance among the form kinds tested in this experiment. The order of surface-glossing is follows ; fancy plywood > metal form > plywood. Water solution type form oil has better performance in surface-glossing than oil solution type form oil. Also, surface-glossing get worse with the elapse of age.

• Journal of the Korea Institute of Building Construction
• /
• v.10 no.3
• /
• pp.57-64
• /
• 2010

This study is to analyze the effects of aluminum form surface coating material on surface quality of concrete. When observing the surface quality of concrete affected by the change of aluminum form surface coating material, in general, as the number of use of the coating material increased, the surface quality of concrete decreased and good surface quality was shown in plywood (hereinafter PW). For epoxy (hereinafter EP) resin, when applying form remover, good surface quality was shown. For the surface roughness of concrete by the application form oil of form remover and the number of use of the coating material, as the number of use increased, highest surface roughness value was shown which meant the leveling was bad, but the surface roughness value in EP and PW was the lowest. Just for EP, when applying form remover, surface roughness value was low. For the number of void for concrete by the application of form remover and the number of use of the coating material, In general, the number of void which was generated when applying form oil the remover decreased.

• Journal of the Society of Naval Architects of Korea
• /
• v.45 no.6
• /
• pp.601-610
• /
• 2008

This paper deals with a new geometrical surface modeling method of forebody's hull form which is fully defined by form parameters. The complex hull form in the forebody can be modeled by the combination of three parts: bare hull, bulbous bow and blending part which connects a bare hull and a bulbous bow. All these subdomain parts are characterized by each own form parameters and constructed with simple surface model. For this, we need only 2-dimensional hull form data and then the form parameters are calculated automatically from these data. Finally, the smooth hull form surfaces are generated by parametric design and fair-skinning. In the practical point of view, we show that this new method can be useful and efficient modeling tool by applying to the hull form surface modeling of Panamax container's forebody.

• Journal of the Korea Concrete Institute
• /
• v.12 no.4
• /
• pp.15-22
• /
• 2000

The objective of this study is to investigate the degree of surface-glossing of flowing concrete, varying with W/C, types of forms and form oils. According to the experimental results, the degree of surface-glossing of flowing concrete is turned out to be higher than that of base concrete, as the slump increases. The degree of surface-glossing of concrete with 40% of W/C is higher than that with 50%. The orders of degree of surface-glossing with the types of forms are as follows : acryle > fancy plywood > metal form > plywood. When water solution type form oil is applied to the surface of forms, we can achieve higher degree of surface-glossing. It shows that the degree of surface-glossing decreases with elapsed time.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.9 no.3
• /
• pp.111-122
• /
• 2000

It is difficult to make shape library for featrue-based modeling because free-form surface is various shaped complicated To make modeling using similar shape feature-based model is easy and fast. Recently RE(Reverse Engineering) technolo-gy is very convenient method to get free-form surface. This study develops surface editor which makes surface modeling to manipulate control points and this study We study on the effective model data management using database system.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2000.10b
• /
• pp.911-914
• /
• 2000

Surface glossing and physical properties of exposed concrete varied with blast furnace slag content are dsicussed in this paper. According to experimental results, as the content of blast furnace slag increases, concrete gains high strength moderately at later stage and surface glossing increase. It shows that glossing decrease with age. Surface glossing shows high as W/B decreases and surface coating is applied. Concrete according to form type shows good results in surface glossing in order for acryl form, fancy form and steel form.

• Design & Manufacturing
• /
• v.17 no.2
• /
• pp.15-21
• /
• 2023

In this study, a diamond turning machine and a laser-assisted machining module were utilized for the complex combined cutting of aspheric shapes and fine patterns on the surface of high-hardness brittle material, silicon. The analysis of material's form accuracy and corrective machining was conducted based on key factors such as laser output, rotational speed, feed rate, and cutting depth to achieve form accuracy below 1 ㎛ and surface roughness below 0.1 ㎛. The cutting condition and corrective machining methods were investigated to achieve the desired form accuracy and surface roughness. The rotational speed of the spindle and the linear feed rate of the diamond turning machine were varied in five stages for the cutting condition test. Surface roughness and form accuracy were measured using both a contact surface profilometer and a non-contact surface profilometer. The experimental results revealed a tendency of improved surface roughness with increased rotational speed of the workpiece, and the best surface roughness and form accuracy were observed at a feed rate of 5 mm/min. Furthermore, based on the cutting condition experiments, corrective machining was performed. The experimental results demonstrated an improvement in form accuracy from 0.94 ㎛ to 0.31 ㎛ and a significant reduction in the average value of the surface roughness curve from 0.234 ㎛ to 0.061 ㎛. This research serves as a foundation for future studies focusing on the machinability in relation to laser output parameters.

• Journal of the Korea Computer Graphics Society
• /
• v.6 no.4
• /
• pp.29-34
• /
• 2000

This paper classifies the structure of the intersection curve between a surface of extrusion and a free-form surface. Our algorithm computes the silhouette curve of the free-form surface with respect to the unique ruling direction of the surface of extrusion. By intersecting the silhouette curve and the base curve of the surface of extrusion, we can classify the topological structure of the intersection curve, and compute all singularities in the intersection curve. Moreover, we can determine which ruling lines of the surface of extrusion intersect the other free-form surface and how many times. This classification provides a robust and efficient method for computing the intersection curve.

• Journal of the Korea Institute of Building Construction
• /
• v.13 no.5
• /
• pp.457-464
• /
• 2013

Traditionally, the material used for the form in reinforced concrete construction has been wood or steel. But recently, aluminum forms have been widely used in wall structures such as apartment buildings. Aluminum is light, easy to handle, and economically advantageous, but the hydrogen gas created due to its reaction with the alkali component in concrete gives rise to air pockets on the concrete's surface, and deteriorates the surface's finishability. In this research, to determine the influence of aluminum material on concrete, the cement paste W/C and its chemical reactivity in alkali and acid solution were analyzed. As a prevention plan, the influence of the number of applications of calcium hydroxide and various surface coating materials was analyzed. Through the analysis, it was found that the surface voids on the aluminum form are the result of the reaction of hydrogen gas with an alkali such as $Ca(OH)_2$. This can be prevented by the surface treatment of $Ca(OH)_2$, separating material and coating material. However, poor surface form and damages to the form are expected to cause quality degradation because of the aluminum-concrete interaction. Therefore, thorough surface treatment, rather than the type of separating material or coating material, is considered the most important target of management.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.2 no.3
• /
• pp.90-95
• /
• 2003

The W-EDM is very important In precision machining of die, punch and small parts of precision products, so this machining method is widely used in various fields of industry. In this study, machining characteristics of Hand Drum Form and surface roughness are investigated experimentally. As Hand drum form has great effect on straightness of cut-surface of workpiece, its evaluation is very important in precision cutting. As experimental material, the mold material, STD11 is used and machined by CNC wire-EDM using the 025mm wire in diameter with repeated cutting up to 6 times. The thickness of workpiece is vaned in 20, 40, 60, 80, 100mm Hand drum form and surface roughness are measured after each cutting. Experimental results show that four times-cutting is optimum in the point of hand drum form and surface roughness.