• International Journal of Highway Engineering
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• v.20 no.4
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• pp.35-46
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• 2018

PURPOSES : The purpose of this study is to compare the lane curing time of natural drying and a lane drying device when painting lines on a highway. METHODS : The painting process was carried out in July 2015 and September 2015, respectively, for the Gimcheon IC - Gimcheon JC. After the painting, measurements were obtained three times at six measurement points located at 20 m intervals on the shoulder line and the dividing line. The curing time was measured for natural drying and drying using a lane drying device, and compared for different pavement types (asphalt, concrete) and paint types (waterborne paint, methyl methacrylate paint). RESULTS : The results of the lane curing time comparison on the highway are as follows. The combination of asphalt and methyl methacrylate paint cured more rapidly during both the natural drying and drying using the lane drying device. Finally, it was cured at least 32.2% and 40.7% faster when using a drying device than in natural drying. CONCLUSIONS : The comparison of lane curing time of the highway showed that the combination of asphalt and methyl methacrylate paint cured more rapidly when using both natural drying and a lane drying device.

• Journal of Engineering Education Research
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• v.23 no.1
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• pp.47-58
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• 2020

Kunsan National University obtained accreditation for its Architecture & Building Engineering Program from the Accreditation Board for Engineering Education in Korea (ABEEK) in 2004 and has offered an ABEEK-accredited degree pathway ever since. Then, in 2018, the university introduced the course-embedded outcomes assessment system as per ABEEK's KEC2015 accreditation criteria. One year into its implementation, the new system allows the measurement and assessment of 10 program outcomes covering 19 curricular modules and 1 non-curricular licensing examination. The system incorporates the four areas of specialization within architectural engineering as well as the three course categories of the math, science, and computer; liberal arts; and engineering core modules under the accreditation scheme. It also takes the students' academic years into account, especially for the mandatory modules offered to all students. Its rubric clarifies the performance criteria, performance level, assessment tools, objectives, and modules. The 2018 course-embedded outcomes assessment system is an ever-evolving structure with regular CQI: Continuous Quality Improvements along the circular process of system establishment → implementation → evaluation as per the virtuous cycle model required for an accredited engineering program.

• Science of Emotion and Sensibility
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• v.6 no.1
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• pp.1-10
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• 2003

Information gathered through experience transforms into knowledge and such knowledge becomes a foundation for intuitive decisions. Based on such background, the following study investigates intuitive decision making on basic elements needed for design concepts and visual conceptualizations. The study consist two phases. first, 12 structural elements of a digital camera and relation between each elements were arranged intuitively on a board. Next, sketches were generated with relationship of structural elements in mind. As a result of the study, concept with intuitive decisions effect structural thinking, various developments, specific operation methods , and sketch expressions. However, study also revealed that the freedom of human emotions don't accord with the qualification map.

• Proceedings of the Technology Innovation Conference
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• 1999.06a
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• pp.245-265
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• 1999

MAUT and AHP are widely used for quantification of subjective judgements in various fields of decision making. This study focuses on the introduction and application of MAUT/AHP method which is a hybrid of MAUT and AHP techniques in R&D project priority setting. This hybrid model can clarify each factors' contribution using MAUT method and can reduce the number of pairwise comparisons of AHP method. This study applies AMUT/AHP method to the evaluation of R&D projects in a Government - funded research institute. To evaluate R&D projects, six evaluation factors are derived. SMART(Simple MultiAttribute Rating Technique) and DVM(Difference Value Measurement ) out of many MAUT methods are used to design the utility function ad AHP is used to allocate the weights among evaluation factors. The major findings of this study can be summarized as follows. First, the SMART/AHP and the DVM/AHP have the same results with the SMART and the DVM, and they are different results with AHP. It is very hard to decide which one is better. Second, MAUT/AHP's strength is analyzed. MAUT reflects utility values of evaluators to alternatives and AHP results objective and consistent weights of factors through pariwise comparisons. Third, its possible application fields are proposed. It is applicable to subjective decision making problems with high complexity and inter-independent factors.

• Transactions of Materials Processing
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• v.18 no.3
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• pp.210-216
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• 2009

Springback, an elastic material recovery after the unloading of stamping tools, causes variations and inconsistencies of final part dimensions. Recently, narrow and long surround molding parts around door frame are applied to high grade automobiles, but there are great difficulties in their die development, construction and tryout because of several springback modes including vertical movement and twist during flange forming process of them. So it is very important to predict springback's quantities of a surround molding part and, moreover, to compensate the die for them adequately, when they can't be corrected by the restrike operation. This paper presents a case study based on the die design for a surround molding part made of stainless steel. The forming and springback predictions, carried out using PAMSTAMP 2G, are reported and compared with the measurement data of the prototype. The predicted springback results were acceptable, so the processes of compensating die using Automatic Die Compensation Module of PAMSTAMP 2G were performed iteratively until the tolerances between the designed shape and the simulation data were satisfied.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.10
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• pp.168-177
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• 2001

Reverse engineering has been widely used for the shape reconstruction of an object without CAD data and the measurement of clay or wood models fur the development of new products. To generate a surface from measured points by a laser scanner, typical steps include the scanning of a clay or wood model, the generation of compatible input curves, the generation of a surface and manufacturing data like G code or STL file. A laser scanner has a great potential to get geometrical data of a model for its frost measuring speed and higher precision. The data from a laser scanner are composed of many line stripes of points including small spikes and noise. A new approach using automated surface generating algorithm is introduced to deal with problems during reverse engineering process. And the input data and the generated surface are represented in IGES format, thus can be supplied to other CAD/CAM software without any data manipulation.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.8
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• pp.145-155
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• 1998

An $H{\infty}$ controller with a roll eccentricity filter is proposed to alleviate the effect of entry thickness variation and roll eccentricity occured in rolling stands themselves of tandem cold mills. A robust controller to the disturbances is designed by H$_{\infty}$ control techniques, which can reflect the input direction of disturbances and the knowledge of disturbance spectrum in the frequency domain. First, fundamental problems in tandem cold mills such as process transport delay inherent in the exit thickness measurement and the feedforward loading of roll eccentricity signals on the exit thickness be overcome by the roll eccentricity filtering and the compensation for the error of gaugemeter thickness estimator. And non-satndard $H{\infty}$ control problem caused by the selection of weighting function having poles on the $J{\omega}$-axis is discussed. The resultant controller composed by an $H{\infty}$ controller and an estimator for the roll eccentricity is evaluated through computer simulations. The effectiveness of the proposed control method is compared to that of the conventional LQ controller method and a feedforward controller for the roll eccentricity, which has been already studied.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.353-354
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• 2006

The automatic inspection system is developed for the formed end part of automotive fuel pipe. The developed system has functions of outer diameter and formed end length measurement by LVDT(linear variable differential transformer) together with burr cleaning of automotive fuel pipe. The measured data are managed and controlled in real time by embedded SPC(statistical process control) program. The system is composed of mechanical part, electronic part and developed software system. These three parts operate automatically by mutual communication with each other. The developed system showed good results in finding inferior goods and efficiency improvement of the fuel pipe production line. It also eliminated the unreliable manual inspection processes and improved the confidence of product quality.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.735-741
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• 2003

A simplified view of array design and application process was introduced. Array design is critical to achieve a successful phased array measurements. A planar microphone array is designed to produce optimum performance and also to fit economic requirement in integrating data acquisition system. Certain performance characteristics are of primary concern when designing arrays. These characteristics include array resolution, spatial aliasing and array sidelobe suppression. Every array has its directional pattern that shows such characteristics. Assuming that a monopole source is located in center, beam-patterns have been simulated varying measurement conditions such as number of sensors. array aperture size, distance between array and source, frequency of interest and so on. Sensor correction was conducted on very channel using magnitudes and phased of FRF with respect to a reference microphone channel. Then with a spiral type array, measurements have been made with two point sources of same frequency in order to investigate array resolving abilities. It is observed that higher frequency source achieves better resolution than lower one does.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.417-421
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• 2006

In this study, colloidal Ag solution was spouted on the surface of the inorganic pigment using the hybridizer system and the spray nozzle. Then, the surface of the inorganic pigment was modified by titanium dioxide in order to possess antibacterial ability. Nano-sized colloidal Ag was made by using a seed sol method in this study. It was confirmed that the size of particle per unit weight becomes enlarged, as the addition of $AgNO_{3}$ increased, and as the time of reaction increased, in the manufacturing process of nano-sized colloidal Ag. The antibacterial measurement of the inorganic pigment showed that the growth of fungus was reduced as the reaction time increased. It was measured that the antibacterial activity was excellent at fixed time frame, after the antibacterial ability appeared in $5{\sim}7$ hours of the antibacterial inoculation experiment. The experiment of titanium dioxide's Photocatalyst effect showed $60{\sim}70%$ efficiency in about 80 minute reaction time of the dissolution results regarding measurements of benzene. It was shown that more than 90% of the dissolution efficiency was achieved in the reaction time of about 30 minute.