• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1997.04a
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• pp.150-155
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• 1997

Rapid Prototyping(RP) is the technique which is used to make prototypes or functional parts directly using the 3-D solid data. Before building the prototype, several processes such as transfering 3D data from CAD system(STL) determination of build-direction, adding support structure and slicing are required. Among the above processes. determination of build-direction is the target of this study. The build direction is determined by many factors according to the objective of the user, like part accuracy, number of support structure, build time, amount of trapped volume, etc, But it is not easy to determine the build-direction because there are many factors and some factors have dependent properties with one another. So, in this study the part accuracy, the number of support structures and build time are considered as the main factor to determine the optimal build-direction. To determine the optimal build-direction for increasing part accuracy, sum of projected area which caused stairstepping effect was considered. The less the projected area is the better part accuracy is About the optimal build-direction to minimize the amount of support structure, sum of projected area of facets that require support structures was considered. About the build time, we considered the minimum height of part we intended. About the build time, we considered the minimun height of part we intended to make.

• The Journal of Advanced Prosthodontics
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• v.14 no.3
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• pp.150-161
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• 2022

PURPOSE. The purpose of the study was to assess the influence of build orientations and density of support structures on the trueness of the 3D printed removable partial denture (RPD) frameworks. MATERIALS AND METHODS. A maxillary Kennedy class III and mandibular class I casts were 3D scanned and used to design and produce two 3D virtual models of RPD frameworks. Using digital light processing (DLP) 3D printing, 47 RPD frameworks were fabricated at 3 different build orientations (100, 135 and 150-degree angles) and 2 support structure densities. All frameworks were scanned and 3D compared to the original virtual RPD models by metrology software to check 3D deviations quantitatively and qualitatively. The accuracy data were statistically analyzed using one-way ANOVA for build orientation comparison and independent sample t-test for structure density comparison at (α = .05). Points study analysis targeting RPD components and representative color maps were also studied. RESULTS. The build orientation of 135-degree angle of the maxillary frameworks showed the lowest deviation at the clasp arms of tooth 26 of the 135-degree angle group. The mandibular frameworks with 150-degree angle build orientation showed the least deviation at the rest on tooth 44 and the arm of the I-bar clasp of tooth 45. No significant difference was seen between different support structure densities. CONCLUSION. Build orientation had an influence on the accuracy of the frameworks, especially at a 135-degree angle of maxillary design and 150-degree of mandibular design. The difference in the support's density structure revealed no considerable effect on the accuracy.

• Journal of the military operations research society of Korea
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• v.27 no.2
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• pp.88-109
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• 2001

Defense minister of the ROK, Kim Bong-sin suggested that the ROK′s military build-up policy will change from "scenario-based" to "capability-based". Entering the 1990s the ROK′s military build-up policy met difficulties to accomplish its goal, modernizing and strengthening of its force structure and weapon systems because of limited budget. The concept of capability-based military build-up could commit a fault in estimating total amount of defense resources required for force planing. This is because that the total amount of defense resources related to force plan for the 15 years is fixed to embody military strategy. The concept of capability-based military build-up plays a role as a constraint in choosing a military strategy. This has no connection with military build-up. Therefore the resources of mid-term military build-up program and scale of annual defense budget could be affected by the situations of its national economy. In this respect, the scale of annual defense budget and resources could be changed in accordance with national economic condition, however, the total amount of resources required to build-up military force for 15 years, namely resources of military force planing requirement for 15 years, is given already for the accomplishment of military strategy. The purpose of this study is to seek a direction of the ROK′s military build-up policy in a viewpoint of capability-based military build-up.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.2
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• pp.130-136
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• 2000

Generally, the build-up printed circuit board manufactured by the sequential process with etching, plating, drilling etc. requires many types of equipments and lead time. Etching process is suitable for mass production, however, it is not adequate for manufacturing prototype in the developing stage. In this study, we introduce a screen printing technology to prototyping a build-up printed circuit board. As for the material, photo/thermal curable resin and conductive paste are used for the formation of dielectric and conductor. The build-up structure is made by subsequent processes such as the formation of liquid resin thin layer, the solidification by UV/IR light, and via filling with conductive paste. By use of photo curable resin, productivity is greatly enhanced compared with thermal curable resin. Finally, the basic concept and the possibility of build-up printed circuit board prototyping are proposed in comparison with to the conventional process.

• 한국공간정보시스템학회:학술대회논문집
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• 2004.05a
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• pp.275-278
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• 2004

This paper focused on problems of design, construction, and maintenance caused by construction implementation processes. They were analyzed through case study of structure safety diagnosis projects. From the case study, it is expected that the introduction of Construction Management from the first stage of procurement will improve construction cost increase or burden on small design company. It strengthens coherent management from design and source contractor selection to build review of responsibility. The coherency will prevent changes in designing or infirm unreliable construction. It is desirable that expert opinions are considered when structure changes and establishment occur and that, if necessary, actions such as source selection, periodic audits, and diagnosis arc checked and fed back to maintenance.

• Journal of the Korean Institute of Rural Architecture
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• v.3 no.1
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• pp.25-40
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• 2001

In this study, I investigate the formation process of the American presbyterian missionary architecture in Cheong Ju area from 1900 to 1945, which we may think 'the part of Korean modern architecture'. I have examined and analyzed the 18 buildings for the sake of the interpretation with the words of formation process and characteristics . And I can put my idea in order as follows. Firstly, the formation process is 1) buy and modify a Korean style (thatch or tile roofed) building for their need and use it as a gate quaters or house, church, hospital, school, book store, 2) build a Korean style (tile roofed) building and use it-house, hospital, school, 3) build a Western style (timber structured and zinc roofed) building and use it- church, 4) build a Western style (masonry structured and tile or zinc roofed) building and use ithouse, church, school and hospital. Secondly, the characteristics is 1) In the Korean style building, the missionaries change into the function to match with their purpose. they modify the Korean style timber structure by influx of building material-brick, glass, carpet etc. they occupy into the Korean existing residential area. 2) In the Western style building, the missionaries build the house correspond with their living pattern. they build the church with the eclectic of Western and Korean timber frame. and also build the house and hospital with the eclectic of Western and Korean masonry structure. their building located in the isolate hill separated from the existing Korean residential area.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.4
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• pp.163-173
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• 1996

Stereolithography is a process used to rapidly produce polymer components directly form a computer representation of the part. There are several considerations to be made for the efficient use of the process. Especially, the build-up orientation of part critically affects the part accuracy, total build time and the volume of support structures. The purpose of tis study is to determine the optimal build-up part orientation for the SLA process with improving part accuracy, and minimizing total build time and the volume of support structures. The forst factor is related to the area of surfaces whioch have staircase protrusions after solidification, the second factor is related to the total number of layers, and the third factor is related to the area of the surfaces which need to be supported with support structures. An algorithm is developed to calculate the staircase area, quantifying the process errors by the volume of materials supposed to be removed or added to the part, and the optimal layer thickness for the SLA system which can handle the variable layer thickness. So the optima l part orientation is determined based on the user's selections of primary criter- ion and the optimal thickness of layers is calculated at any part orientations.

• KSCI Review
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• v.1 no.2
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• pp.73-94
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• 1995

In this paper, design of efficient NDB(Network Data Base) for the activation plan of chain information network. The DB structure build up, logical structure, store structure, physical structure, the data express for one's record, and the express using linked in the releation of data. Also express as hierarchical model on the DSD(Data Structure Diagram) from the database with logical structure. Each node has express on record type, the linked in course of connective this type, the infuence have efficent of access or search of data, in the design for connection mutually a device of physical, design for database, and construction a form of store for logical. Also activation of chain information network of efficent, using POS(Point Of Sale) system in OSI(Open Systems Interconnection) environment for network standardization, and build up network a design for system.

• International Journal of Precision Engineering and Manufacturing
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• v.4 no.4
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• pp.51-56
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• 2003

Generally, the build-up printed circuit board manufactured by a sequential process involving etching, plating, drilling, etc, which requires many types of equipments and long lead time. Etching process is suitable for mass production, however, it is not adequate for manufacturing a prototype in the development stage. In this study, we introduce a screen printing technology for prototyping a build-up printed circuit board. As for the material, photo/thermal curable resin and conductive paste are used for the formation of dielectric and conductor. The build-up structure is made by subsequent processes such as formation of a liquid resin thin layer, solidification by a UV/IR light, and via hole filling with a conductive paste. By use of photo curable resin, productivity is greatly enhanced compared with thermal curable resin. Finally, the basic concept and the possibility of build-up printed circuit board prototyping are proposed in comparison with the conventional process.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.25-32
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• 2022

As a project delivery method, Design-Build (DB) has provided owner, architect, and contractor groups with a process of early design and rapid construction for the past three decades. Although there are many benefits to using standard DB, dissatisfaction has arisen due to limitations to innovate, limited owner involvement during design, and often lengthy procurement. Progressive Design-Build (PDB) has become an appealing alternative providing benefits not seen with standard DB. This paper investigates how PDB impacts a project and how it compares against standard DB; it also presents a proposed framework for evaluating the owner's responsibility and assessment of a project, which we named the "Four Pillars of Project Success". The four pillars are defined with respect to an owner's responsibility and assessment of a project, including project predictability, project risk, project schedule, and project cost. We conducted a literature review, examined several public project case studies, analyzed PDB project information collected by the Design-Build Institute of America (DBIA), and held stakeholder interviews with owners, contractors, and architects who have used both PDB and standard DB. This paper offers insight into PDB's structure and outcomes so an owner group can make an informed decision when considering PDB as their next construction contracting method.