• Journal of KIBIM
• /
• v.8 no.1
• /
• pp.43-55
• /
• 2018

Recently, there have been increasing studies on the application of digital technology, which has its focus of the irregular building. However, most of these studies have not clarified the objective of the technology and the effectiveness of professional manpower on its performance. This study analyzes actual used technology and the role of specialty contractor. It presents a framework to quantify the performance of the specialty contractor. For these purposes, this paper presents a proposed method to evaluate the activities of specialty contractors using a queueing model. As an attempt to verify the model, an actual irregular building project, in which digital fabrication is applied, is investigated during the construction phase. In order to collect the digital fabrication data, digital fabrication reports and specialty contractor's work log of project are reviewed. In addition, Digital Fabrication input personnel, productivity data are collected through interviews with experts involving in the case project. Analysis of specialty contractor's performance in digital fabrication reveals that the wait status of project participants varies probabilistically depending on the digital technology application level. The results of this study are expected to contribute toward the improvement of the production level in the construction industry.

• Journal of the Korea Institute of Building Construction
• /
• v.23 no.3
• /
• pp.251-260
• /
• 2023

The construction of free-form structures with intricate curved exteriors necessitates the use of bespoke molds. To fulfill this requirement, a blend of Phase Change Material(PCM) and Ultra-High Performance Concrete(UHPC) is utilized. PCM endows the solution with recyclability, while UHPC facilitates the effortless execution of curvature in the mold fabrication process. However, it's worth mentioning that the melting point of PCM hovers around 58-64℃, and the heat emanating from UHPC's hydration process can potentially jeopardize the integrity of the PCM mold. Hence, experimental validation of the mold shape is a prerequisite. In the conducted experiment, UHPC was poured into two distinct mold types: one that incorporated a 3mm silicone sheet mounted on the fabricated PCM mold(Panel A), and the other devoid of the silicone sheet(Panel B). The experimental outcomes revealed that Panel A possessed a thickness of 3.793mm, while Panel B exhibited a thickness of 5.72mm. This suggests that the mold lacking the silicone sheet(Panel B) was more susceptible to the thermal effects of hydration. These investigations furnish invaluable fundamental data for the manufacturing of ultra-high strength irregular panels and PCM molds. They contribute substantially to the enrichment of comprehension and application of these materials within the realm of construction.

• Korean Institute of Interior Design Journal
• /
• v.17 no.2
• /
• pp.150-161
• /
• 2008

It requires more close cooperation process and mediator for smooth communication in this industry structure where design and engineers are separated. The database of design integrates separate system and helps connection between organizations. The application category is utilized variously from formation to operation. Architectures addressed in this content as Frank Gehry and Nox are making differentiated design on the base of 3d digital methodology and using it widely from generation to fabrication. Especially they got to be free from the generative limit as it became available to analyse, digital surface organization, and realize the complex system form. Now more integrated and delicate works got to be affordable owing to various kinds of improved CNC, RP(rapid-prototype) machines, and architecture hardwares. With a linkage of software now at their disposal, architects can create a digital model of a building and all of its design elements, and in turn use this 3d information to construct actual building components using machines driven by CNC and other advanced manufacturing techniques. Digital technologies are enabling a direct correlation between what design and construction, thus bringing to the forefront the issue of the significance of information, the production, communication, application, and control of digital information in the industrial system. The central requirement is the clear, reliable, and consistent exchange of information among all parties involved in creating a given project.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.10a
• /
• pp.115-118
• /
• 2002

The purpose of this paper is to design a pick-up for the small form factor optical disk drive and to fabricate a micro-compensatory lens for the pick-up using the micro-compression molding process. At design stage, the optical elements including the objective lens and the compensatory lens are miniaturized. The height of pick-up and free working distance are designed as 2mm and 0.2% respectively. To analyze the fabricated micro-compensatory lens, the system was analyzed using the surface profile of the fabricated micro-compensatory lens and CODE V which is commercial software. The RMS wave front aberration of the system using fabricated micro-compensatory lens is 0.01677λ which is lower than Marechal's criterion, 0.07λ.

• Journal of the Korean Ceramic Society
• /
• v.29 no.9
• /
• pp.695-704
• /
• 1992

In (Pb, La)(Zr, Ti)O3 ceramic system, the functionally gradient material (FGM) was developed, and its processing and properties were investigated. The FGMs were successfully prepared through doctor blade method with acrylic binder system as well as mold stacking press method. The ultrasonic treatment was very effective for particle dispersion in slurry, and it lead to form clack-free green films. The strain-voltage characteristics of the FGM system was significantly improved which fabricated between a high piezoelectric-low dielectric and a low piezoelectric-high dielectric composition layer.

• Journal of Welding and Joining
• /
• v.33 no.6
• /
• pp.1-5
• /
• 2015

Additive Manufacturing defines the fabrication of objects by successive consolidation of materials, layer by layer, according to a three-dimensional design. The numerous technologies available today were recently standardized into seven categories based on the general method. Each technology has its own set of advantages and limitations. Though it very much depends on the field of application, major assets of additive manufacturing compared to conventional processing routes are the ability to readily offer complexity (in terms of intricate shape and customization) and significant reduction of waste. On the other hand, additive manufacturing often suffers of relatively low production rates. Anyhow, additive manufacturing technologies is being given outstanding attention. In particular, metal additive manufacturing emerges as of great significance in industries like aerospace, automotive and tooling. The trend progresses toward full production of high value finished products.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.10a
• /
• pp.1080-1083
• /
• 1997

Micro-stereolithography is a newly proposed technology as a means that can fabricate 3D micro-structures of free form. It makes a 3D structure by dividing the shape into many slices of relevant thickness along honzontal surfaces, hardening each layer of slice with a laser, and stacking them up to a des~red shape. Scale effect becomes important in this micro-fabrication process, d~fferently from the conventional stereolithography. To realize this micro-stereolithography technology, we developed an equipment using Ar+ laser, xyz stages, controllers and all the optic devices. Using the equipment, a number of micro-structures were successfully fabricated including a winecup of several tens of micrometers.

• Journal of the Korean Society for Precision Engineering
• /
• v.19 no.12
• /
• pp.171-178
• /
• 2002

With increasing the needs for micro and precision parts, micro machining technology using micro tools has been studied to fabricate a small part with high density such as electronics, optics, communications, and medicine industry more than before. Though these micro tools have developed rapidly, it is difficult to apply them to micro fabrication technologies, because of the inherent manufacturing. In this study, micro tools (WC) to produce micro structures and parts were manufactured by cylindrical grinding machine employing ELID (Electrolytic In-process Dressing) technique and the micro tools are fabricated as square shape with the dimension less than 100${\mu}{\textrm}{m}$. With the micro tools on the same machine, characteristics of micro grooving and drilling are evaluated. Also we compare normal micro machining with ultrasonic micro machining on the vibration table. It is confirmed that the developed micro tools are fully applicable to micro grooving, micro drilling and free form cutting.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.1 s.94
• /
• pp.68-74
• /
• 1999

One of the recent changes in machining technology is rapid application of micro- and high precision grinding processes. A fine groove generation is necessary for the fabrication of optic, electronic and semiconductor parts, and achieved by chemical or mechanical processes. Slot grinding is very efficient for the generation of micro ordered groove with hard and brittle materials. As slot grinding is continuous, the ground depth become gradually shallow because of wheel wear. The form accuracy become worse from the increase of ground slot width by the loading phenomena at wheel side, results on chipping damage of the workpiece. The experiments achieve to the enhancement of the form accuracy and chipping free of the brittle materials using V shaped cast iron bonded diamond wheels. In this study we focused on the investigation of the effect of the high pressure air jet on the grinding characteristics. As a results, we found that the high pressure air jet is very effective on the reductions of the wheel wear, enhancement of the form accuracy.

• Proceedings of the Safety Management and Science Conference
• /
• 2007.11a
• /
• pp.27-37
• /
• 2007

Preliminary investigation of CC process indicates that the process is feasible and has significant potential in construction automation approach of large objects. The process aims at automated construction of whole houses as well as sub-components. The potential of CC became evident from the initial investigations and experiments with various materials and geometries. Using this process, a single house or a colony of houses, each with possibly a different design, may be automatically constructed in a single run as shown on