• The Journal of Korean Academy of Prosthodontics
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• v.32 no.2
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• pp.327-353
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• 1994

This study was performed to evaluate the effects of number and alignment of implant fixture and various bar designs on the retention of denture and the stress distribution. Six kinds of photoelastic mandibular models and nine kinds of overdenture specimens were designed. A unilateral vertical load was gradually applied on the right first molar to calculate the maximal dislodgement load of each specimen. A unilateral vertical load of 17 Kgf was applied on the right first molar and a vertical load of 10 Kgf was applied on the interincisal edge region. The stress pattern which developed in each photoelastic model was analyzed by the reflection polariscope. The results obtained were as follows: 1. The maximal dislodgement load reversely increased with the distance from the loading point to the implant fixture, while it linearly increased with that from the most posterior implant fixture to the mesial clip. The maximal dislodgement load also increased with the use of a cantilever bar. 2. Under the posterior vertical load, the stress to the supporting tissue of the denture base increased with the distance from the loading point to the implant future. The stress concentration on the apical area of the implant future reversely increased with the distance from the loading point to the implant future. 3. In the overdentures supported by two implant fixtures under the posterior vertical load. the specimen implanted on lateral incisor areas with a cantilever bar exhibited more favorable stress distribution than that without a cantilever bar. The specimen implanted on the canine areas without a cantilever bar, however, exhibited more favorable stress distribution. 4. In the overdentures supported by three implant fixtures. the specimen implanted ell the midline and canine areas exhibited more favorable stress distribution than that implanted oil the midline and the first premolar areas. 5. In the overdentures supported by four implant fixtures. the specimen implanted with two adjacent implant fixtures exhibited more favorable stress distribution than that implanted at equal distance under the posterior vertical load. 6. Under the anterior vertical load, the overdentures supported by three implant fixtures exhibited stress concentration on the supporting structure of the middle implant future. In overdentures supported by two or four implant futures, no significant difference was noted in stress distribution between the types of bars. These results indicate that the greater the number of implant fixtures, the better the stress distribution is. A favorable stress distribution may be obtained in the overdentures supported by two or three implant fixtures, if the location and the design of the bar are appropriate.

• Imaging Science in Dentistry
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• v.33 no.2
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• pp.79-83
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• 2003

Purpose : To assess the relationship between the direction of the indicating rod of the radiographic stent for ideal prosthetic design and the actual possible path of implant fixture placement when residual ridge resorption is considered. Materials and Methods: The study materials consisted of 326 implant sites (male 214 cases and female 112 cases) from a total of 106 patients (male 65 patients and female 41 patients) who desired implant prostheses. Computed tomography of patients were taken and reformatted using ToothPix/sup (R)/ software. Bony defects, bony sclerosis, the change of the direction of indicating rod, and root proximity of the adjacent teeth were examined on the CT-derived images. Results: The rate of the irregular crestal cortex was relatively high on premolar and molar area of maxilla. Mandibular molar area showed relatively high rate of focal sclerosis on the area of implant fixture insertion. The position of the indicating rods were relatively acceptable on the molar areas of both jaws. However, the position of the indicating rods should be shifted to buccal side with lingual rotation of the apical end on maxillary anterior teeth and premolar area. Conclusion: Clinically determined rod direction and position of the indicating rod for implant placement was not always acceptable for insertion according to the reformatted CT images. The pre-operative treatment plan for implant should be determined carefully, considering the state of the alveolar bone using the reformatted CT images.

• The Journal of Korean Academy of Prosthodontics
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• v.41 no.3
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• pp.271-287
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• 2003

Statement of problem: Resonance frequency analysis (RFA) has been increasingly served as a non-invasive and objective method for clinical monitoring of implant stability. Many clinical studies must be required for standardized baseline data using RFA. Purpose: This study was performed to evaluate RFA value changes in two stage surgery group and one stage surgery group in patients. Material and method: Forty-seven mandibles in consecutively implant installed patients were selected for this study and 141 fixtures were installed. Ninety-three fixtures were double threaded, machined surface design ($Br{\aa}anemark^{(R)}$ MK III, Nobel Biocare AB, Goteborg, Sweden) and 48 fixtures were root form, threaded, HA-coated surface one ($Replace^{TM}$, Steri-Oss/Nobel Biocare AB, USA). Among those, each 10 fixture was installed in one stage group patients. ISQ values were measured using $Osstell^{TM}$ (Integration Diagnostics Ltd. Sweden) during fixture installation, at healing abutment connection and in the loading period for two stage surgery group patients and during at each 4, 6, 8, 10, 12week and in the loading phase for one stage surgery group patients and evaluated the changes according to the time and fixture type. Results: In two stage surgery group, mean and SO of ISQ values of machined surface implants were $76.85{\pm}3.74,\;75.76{\pm}5.04,\;75.73{\pm}4.41$ and those of HA-coated surface implant were $75.05{\pm}6.23,\;77.58{\pm}5.23,\;78.32{\pm}4.29$ during fixtures installation, at healing abutment connection and in the loading period, respectively. In one-stage surgery group, the ISQ values of machined surface and HA-coated surface implants decreased until 4 or 6 week and maintained at plateau for 1-3 week and increased to the loading period. Conclusions: Machined and HA-coated surface implants showed minimal ISQ changes with time if they were installed at the sites showing at least intact cortical plate and good bone qualities. And HA-coated implants had a tendency to show somewhat increased ISQ values with time.

• Korean Institute of Interior Design Journal
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• no.25
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• pp.229-235
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• 2000

Although Frank Lloyd Wright represents himself as one of the greatest American master architect, the master architects contribution towards the advancement in the modern history of architecture goes beyond just creating landmark buildings. Through out his life, he was the leading architect not only in the area or architectural design but showed his talent in interior architecture, furniture, fabric, lighting fixture, art glasses, tablewares, silver wares as well as in graphic design which should cover all the elements related to the "total design" in architecture. As seen in his architectural design, the "total design" concept also reflects both beauty and logic of the nature and strengthens his theory of the organic architecture design. The research began with finding out the relationship between his architecture, nature and the supporting design elements mentioned above. the purpose of the research is to analyze the relationship of the spatial organization and the design elements in Frank Lloyd Wrights architectural works from the point of "total design" view and provide the valuable guide line for the development of the modern interior design. His design theory, based on the fundamental ideas of the nature, his organic architecture design, and reference materials to support total design concept will be discussed on chapter 2. And on chapter 3, application of the total design in his actual project will be analyzed. The data and analyzation have been completed based on written references and actual visit to the project sites. Frank Lloyd Wright placed highest value on the human beings and enjoyed presenting new ideas and forms to create better environment for the humans through his architecture and interior design projects. While he was presenting new ideas he continued to support design for democracy which has close relationship to the new frontier spirit of America. He was the master architect for the general society with accurate understanding of the life style of the public with design sensitivity shown in his concept of the total design.s concept of the total design.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.2
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• pp.42-50
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• 2008

There are many plans of the high-rise buildings these days in domestic and will be constructed from now on. It is required to develop energy saving techniques immediately because the high-rise buildings consume a lot of energy. The most effective energy savings method is the application of the efficient lighting designs and fixtures. The purpose of this study is to analyze a trend of lighting design, fixture and control system between overseas and domestic. It can be used the guide line for the high-rise buildings in domestic application.

• Journal of Welding and Joining
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• v.34 no.5
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• pp.41-46
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• 2016

Welding is an absolutely essential component of industries such as the automotive industry, the construction industry and even the aviation industry. Although it is a widespread technology it is still characterized by lots of uncertainties. This still requires well experienced and highly skilled workforce to design and perform safe welding processes. The early knowledge of distortion and residual stresses is almost an issue which is influenced mainly by the welding parameters and the fixture design. But more and more engineers want to know as well final properties of the assembled components. With the beginning of the computer age in the 1970s and 1980s last century, the numerical prediction of manufacturing processes using FEM was gradually getting better and has established itself in the industry since the 1990s as a standard tool. Unlike in metal casting and forming industry, however, the everyday use of FEM- simulation tools for welding processes eked out a shadowy existence for a long time. This paper will give a short classification of welding simulation types and a structured overview on the technical questions. Selected case studies and the benefits achieved through simulations with the software Simufact welding are discussed. Finally an outlook on future developments will be given.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.2
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• pp.223-227
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• 2013

Dust collecting performance of cyclone collector for oil mist was alalyzed in the study. The purposes of using cutting fluid during cutting have been colling, lubricating, chip washing and anti-corroding. However, the present manufactaring industry restricts the use of cutting fluid because cutting fluid confains poisonous substances which are harmful to the human body. Also, the optimum design oil-mist collector. The new oil mist collector was designed. In the near future, this device must be tested in the real machining center and CNC machine. Cutting using oil-mist showed better cutting characteristics than dry, air and fluid cutting with respect to by cutting force, tool wear and surface roughness. The model(A, B Type cyclone) of the set of fixture and alveolus are made by using a CAE software. Finally, we have obtained a model A Type solution by using orthogonal array. Therefore, it could be confirmed that as the model-A was increased and model-B was decreased, cut diameter was decreased.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.4
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• pp.143-149
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• 2018

A cable tray is a fixture to support and protect electrical and communication cables. In this study, a roll-forming analysis is conducted to produce an all-in-one cable tray. The number of process stands is calculated using an empirical formula. By applying bending methods to the design of the roll flower pattern, the final process stands and forming angles are determined. The shape and stress variations in the cable tray are modeled and observed by roll forming analysis using LS-DYNA Software. The width of the side rail and the maximum stress on all stands does not exceed the reference values. The forming machine and rolls are manufactured based on the results of the roll forming analysis. In addition, all-in-one cable trays satisfy the National Electrical Manufacturers Association standards when they are manufactured according to this design.

• Korean Journal of Computational Design and Engineering
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• v.14 no.6
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• pp.415-423
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• 2009

Because of the fast changing car design and increasing facilities, manufacturing process of cars is getting more complex now a days. Particularly, car manufacturing system that consist of automated devices, applies various simulation techniques to validate device motion and detect collision. To cope with this problem, traditional manufacturing system deployed test-run with the real devices. However, increased computing power in a contemporary manufacturing system changes it into realistic 3D simulation environment. Similarly, managed device data that was generated using 2D traditionally, can be converted to 3D realistic simulation. The existing problem with 3D simulation is disjoint data interaction between different work stations. Consequently, JIGs, fixing the car part accurately, are changed according to fixing position on the part or a part shape properties. In practice, the 3D JIG data has to be managed according to kinematic information, but not of its features. However, generating kinematic information to the 3D model repeatedly according to frequent change in part is not explained in current literatures. To fill this knowledge gap, this paper suggests an improving method of rendering 3D JIG kinematics information to simulation model. Thereafter, it shows the result of implementation.

• Korean Institute of Interior Design Journal
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• no.5
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• pp.45-52
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• 1995

Frank Lloyd Wright, a master of the 20th Century Ar-chitecture, contributed tremendously in creating a wholly new form of American architecture called Prairie Style. His idea behind the development of the building structur-al system, organic relationships between inner and outer space, horizontal vertical lines, and idea of extending and expanding interior spaces came from nature. He had completed over 390 projects throughout his life and 90% of those projects were residential design. The most typical characteristic shared by many of his residential design was that each design element, whether it is functional or aesthetical, has close relationship to or-ganic nature, human scale, theoretical floor plants, and maximum emphasis on horizontal lines in respect to na-ture. His concept of "flow of spaces" reformed common the-ory of room next to room in a enclosed space. His sense of "wall" was no longer the side of a box. Careful selec-tion of finishing materials, colors, and natural images en-hance the design as well. F.L. Wright was an artist, designer, and architect who believed the exterior space should have direct relationship to the interior space. His architectural philosophy was not only to design exterior of architecture but also to ful-fill his space through the careful development of interior elements such as furniture, and lighting fixture. Even the patterns for leaded glass windows were designed to have unified appearance from outside to inside of the house. The objective of this study was to analyze floor plans, spatial organizations, and interior design elements of the houses which represent the best of F.L. Wright's design principles and philosophy behind Prairie Style. The meth-od used to collect informations for this study was based on books, articles, journals, and actual site visits. actual site visits.