• Korean Journal of Computational Design and Engineering
• /
• v.20 no.3
• /
• pp.269-280
• /
• 2015

Although BIM has been recognized as one of the main streams that advance the construction industry worldwide, it is difficult to ensure the quality of BIM data due to the problems such as internal errors of BIM tools and lack of guidelines that enhance design quality. Such problems cause designers, constructors, and project owners to hesitate applying it to their business. The main objective of this research is to develop a BIM guide for public project owners that is to be usable at the design phase of the public projects. To meet the objective, the study invited 10 BIM experts from Korean construction industry and operated workshops with focus group interview methodology. As well, a number of BIM guidelines from the BIM advanced countries were reviewed to identify valuable contents for the guide. There are four main parts in the guide developed: BIM design procurement process guide, Request for Proposal development guide for BIM design, BIM execution plan development and evaluation guide, and BIM output and deliverables review and evaluation guide.

• Proceedings of the KSME Conference
• /
• 2007.05a
• /
• pp.1585-1589
• /
• 2007

The HANARO, a 30 MW multi-purpose research reactor in Korea, will be equipped with a neutron guide system, in order to transport cold neutrons from the neutron source to the neutron scattering instruments in the neutron guide hall near the reactor building. The neutron guide system of HANARO consists of the in-pile plug assembly with in-pile guides, the primary shutter with in-shutter guides, the neutron guides in the guide shielding room with dedicated secondary shutters, and the neutron guides connected to the instruments in the neutron guide hall. The functions of the in-pile plug assembly are to shield the reactor environment from a nuclear radiation and to support the neutron guides and maintain them precisely oriented. The primary shutter is a mechanical device to be installed just after the in-pile plug assembly, which stops neutron flux on demand. This paper describes the mechanical design of the in-pile plug assembly and the primary shutter for the neutron guide system at HANARO. The design of the guide shielding assembly for the primary shutter and the neutron guides is also presented.

• Design & Manufacturing
• /
• v.17 no.3
• /
• pp.8-14
• /
• 2023

In this study, basic research was conducted on manufacturing technology of thick-walled light guide a component that controls the light source of automobile lamps. As a preliminary study for manufacturing the final injection molded parts, a model for analyzing the influence of micro patterns on light guides is presented. The optical characteristics of the light guide were analyzed according to the change of the curvature radius of the micro-optical pattern, and the injection molding characteristics of the light guide according to the change of injection molding conditions were analytically evaluated. It was confirmed that the luminance uniformity improves as the R value decreases for changes in the micro-pattern R value, but it was confirmed that there are technical limitations in actual injection mold core processing and high-replication injection molding. Injection molding analysis showed that cooling channel design is very important compared to general injection molding due to thick-wall characteristics and thickness variation. It was also confirmed that the cooling channel has a great influence on the cycle time and birefringence result due to residual stress. As a result of analyzing the influence of filling time, holding condition, and cooling on shrinkage, it was found that the cooling water temperature has a significant effect on the shrinkage of ultra-fine light guide parts, and the holding condition also has a significant effect.

• Journal of the Korean Solar Energy Society
• /
• v.27 no.2
• /
• pp.79-85
• /
• 2007

The performance of in-line duct fan depends on the design parameters of impeller and guide vane such as sweep back angle of impeller hub, guide vane angle etc. In this study four kinds of impellers having different sweep back angles, $0^{\circ}$, $17.5^{\circ}$, $35^{\circ}$, $52.5^{\circ}$ with 8 guide vanes, and different guide vane angles, $15^{\circ}$, $30^{\circ}$, $45^{\circ}$ were selected and their performance measured to investigate the effects of design parameters. The results show that both sweep back angle of impeller hub and the guide vane angle have large effect on the efficiency. Especially, it was found that the mixed flow impellers having sweep back angle between $17.5^{\circ}$ and $35^{\circ}$ gave good performances for in-line duct fan.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.57 no.4
• /
• pp.271-282
• /
• 2021

This study aims to understand the opening efficiency of the finless porpoise escape guide net by the type of extension net that is the part to which the escape guide net is attached in stow net. To this end, extension nets were manufactured in full size and the net mouth area and towing tension were investigated according to the towing speed (0.2, 0.4, 0.6 and 0.8 m/s) and the type of extension net (25 mm net and raschel net) in the water tank. As a result, the net mouth area of the guide net was larger when the raschel net was used for the extension net than when the 25 mm net was used under all towing speeds. In addition, regardless of the type of extension net, the net mouth area reached about 80% of the maximum value at a towing speed of 0.4 m/s. In the field, fishing operation of stow net is performed only when the current speed is above 0.4 m/s. Therefore, the speed of 0.4 m/s was confirmed as a meaningful value to determine whether it is possible to operate. As a result of analyzing the relationship between the net mouth area of the guide net and the towing tension, it was confirmed that the difference in the net mouth area of the guide net according to the type of the extension net was due to the difference in the solidity ratio.

• IEIE Transactions on Smart Processing and Computing
• /
• v.6 no.2
• /
• pp.124-128
• /
• 2017

A light guide improves the spatial resolution of a gamma ray imaging system by diffusing the scintillation light. Similarly, light diffusion film, which has been applied to flat-panel-display engineering, spreads the light from the light guide panel. In this study, we adopted light diffusion film for the light guide of a gamma ray imaging system, and evaluated its diffusion characteristics. We compared the light diffusion performance of the film to an ordinary acrylic plate. As a result, the diffusion film widely spreads scintillation light. As for the thickness of the light guide, we acquired more distinct images with three films overlapped than with an acrylic plate. We expect light diffusion film to be a promising candidate for light guides in gamma ray imaging systems.

• Transactions of the Korean hydrogen and new energy society
• /
• v.23 no.2
• /
• pp.156-161
• /
• 2012

In case of commercializing of the hydrogen fuel cell vehicle, the suitable emergency response guide is necessary to prepare an accident. In order to suggest the suitable guide for the domestic affairs, the existing external guide about GM, Ford, Honda, and Hyundai was reviewed. The emergency response guides in CAFCP and main FC vehicle makers were included in the analysis. As the results, it was found that the design and make of vehicle for the domestic user are demanded in the emergency response and the guide is made with the shut-down manual picked out for the rescuer and repair man as well as user.

• Wind and Structures
• /
• v.16 no.2
• /
• pp.213-224
• /
• 2013

One of the key issues affecting the promotion of solar water heaters in Taiwan is the severe impact of typhoon each year. An experimental study was conducted to investigate the wind uplift characteristic of a solar collector model with and without a guide plate. The guide plate with different lengths and orientations with respect to wind direction was adopted. It is found that the wind uplift of a solar collector is associated with the tilt angle of the flat panel as expected. A cavity formed between the guide plate and the flat panel has a significant effect on the distributions of streamwsie and lateral pressure. Reduction in uplift is essentially coupled with the projected area of a guide plate on the lower surface of the tilt flat panel.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.3D
• /
• pp.393-400
• /
• 2006

This study is intended to examine the characteristics of driver in the use of guide sign in urban areas. The good and bad points about guide sign based on landmark point and guide sign based on street name are demonstrated, and driver's preference between them are studied. The questionnaires given to general persons deal with general guide signs and road maps, and are designed to see if they can find out current location on the road map with guide sign. According to the results, drivers prefer guide sign based on street name to guide sign based on landmark. And guide sign based on street name took less time to find current location than with guide sign based on landmark.

• The KSFM Journal of Fluid Machinery
• /
• v.17 no.5
• /
• pp.19-26
• /
• 2014

The cross flow turbine attracts more and more attention for its relatively wide operating range and simple structure. In this study, a novel type of micro cross flow turbine is developed for application to a step in an irrigational channel. The head of the turbine is only H=4.3m and the turbine inlet channel is open ducted type, which has barely been studied. The efficiency of the turbine with inlet open duct channel is relatively low. Therefore, a guide nozzle on the turbine inlet is attached to improve the performance of the turbine. The guide nozzle shapes are investigated to find the best shape for the turbine. The guide nozzle plays an important role on directing flow at the runner entry, and it also decreases the negative torque loss by reducing the pressure difference in Region 1. There is 12.5% of efficiency improvement by attaching a well shaped guide nozzle on the turbine inlet.