• 한국공작기계학회논문집
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• 제16권5호
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• pp.48-54
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• 2007

Surface of rapid prototype has inevitably stair-stepping error, which is attributed to the continuous building process of 2 dimensional area. In this study, rounded edge model was established to estimate the roughness of inclined surface which has stair-stepping error. To investigate the roughness of rapid prototypes, specimens that have various surface inclinations were manufactured by various types of RP machines. As the surface inclination increased, the roughness of the specimens manufactured by SL, FDM, or LOM process decreased, which coincides with the simulation results. However, surface roughness of 3DP specimen was almost independent of the inclination. Furthermore, as the angle of surface increased, roughness of poly-jet specimen also increased, which is attributed to the frictional behavior between writing head and scanned area.

• 한국도로학회논문집
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• 제16권4호
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• pp.11-19
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• 2014

PURPOSES: This study is to suggest the improvement for bus rapid transit system in Seoul METHODS: The maintenance cost for bus lane damages and plastic deformations are increased by bus passing speed, heavy bus weight, and climate change (localized torrential downpour, subtropical climate) and the accident risk has been increased. RESULTS: Recent analysis of pavement damage indicates that bus lane damage caused by heavy weight is overwhelming and it is urgent to prepare countermeasures. CONCLUSIONS : Pavement data of bus rapid transit system, bus transit numbers and pavement damage elements were analyzed. By analyzing pavement maintenance, design and construction, the countermeasures for the improvement of bus lane pavement and effective maintenance were suggested.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 I
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• pp.504-511
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• 2001

In this research, we developed a computer program that designs a centrifugal impeller and diffuser, and predicts the far-field noise from the impeller. To design the impeller optimally, the TEIS model, which was originally developed by Japkise(1985), and the mean-line analysis are combined to predict the performance and design the optimal impeller simultaneously. The geometric configurations are provided by a GUI software (iDesignComp). The noise from impeller can be computed by the rapid loading procedure, which generates a surface between two blades and calculates the pressure distributions on the suction and pressure sides. The steady loading noise is computed by the rotating dipole source distribution via Ffowcs Williams & Hawkings equation.

• Mass Spectrometry Letters
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• 제7권4호
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• pp.91-95
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• 2016

In recent years, matrix-free laser desorption ionization (LDI) for mass spectrometry of thermally labile molecules has been an important research subject in the pursuit of new ionization methods to serve as alternatives to the conventional matrix-assisted laser desorption ionization (MALDI) method. While many recent studies have reported successful LDI of thermally labile molecules from various surfaces, mostly from surfaces with nanostructures, understanding of what drives the LDI process still requires further study. This article briefly reviews the thermal aspects involved in the LDI mechanism, which can be characterized as rapid surface heating. The thermal mechanism was supported by observed LDI and postsource decay (PSD) of peptide ions produced from flat surfaces with special thermal properties including amorphous Si (a-Si) and tungsten silicide ($WSi_x$). In addition, the concept of rapid surface heating further suggests a practical strategy for the preparation of LDI sample plates, which allows us to choose various surface materials including crystalline Si (c-Si) and Au tailorable to specific applications.

• 산업기술연구
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• 제19권
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• pp.163-172
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• 1999

This study is conducted on the flexural toughness and flexural fatigue test to fine the mechanical properties of steel fiber reinforced rapid-set cement concrete. Experimental investigation is examined according to fiber contents(0, 0.4, 0.7, 1.0, 1.5%), fiber aspect ratio(58, 60, 83), fiber type (hooked, crimped fiber), and cement type (normal portland & rapid-set cement). The principal results obtained through this study are as follows; toughness and fatigue resistance tend to considerably increase with fiber contents, fiber aspect ration. And hooked fiber is improved better than crimped fiber. Concrete using rapid set cement is increased strength properties compared with concrete using normal portland cement, but relative strength properties behavior and fatigue resistance show a tendency to decrease a little.

• 한국주조공학회지
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• 제2권1호
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• pp.12-18
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• 1982

The present investigation was made to abtain a fine distribution of Pb Particles in AL - Pb binary alloys , which have a broad miscibility gap and large specific difference, by means of rapid Cooling of the molten alloys. Al-2.4% Pb, Al-5.5wt% Pb and Al-8.0wt % Pb alloy were used. The rapid cooling operation was performed by free falling of homogeneous liquid Al-Ph alloys into the water-cooled copper mold, and thermal analysis was made. Microstructures were observed, and variations of size and number of Pb particles were analysicle analyzer. By the result of examination with the varing cooling rates 100 to $210^{\circ}C/sec$ fine distributions of Pb particles were obtained with high cooling rate. Under same cooling condition, the best rapid cooling effect was recognized in Al-5.5wt% Pb alloy.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 추계학술대회 논문집
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• pp.841-845
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• 1996

Reverse engineering enables a fast creation of CAD model from an existing part without any technical drawing or digital data. This method of data acquisition is necessary in several industrial applications when the modification of an existing product design has to be performed and verified afterwards. In this paper, the surface of an existing ship propeller was measured by a tactile measuring system and the acquired point data of the surface were used for modeling of a solid model in CAD system. By using LOM and casting processes, an aluminum propeller for functional test was manufactured and then its accuracy was measured by a laser scanner and compared with the origin릴 CAD data. As the results show, the use of LOM as a rapid prototyping process and casting as a secondary process delivers a functional prototype propeller which can be used for test purposes.

• 화약ㆍ발파
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• 제32권1호
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• pp.18-22
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• 2014

코레일(한국철도공사)는 "지진가속도계측기 설치 및 운영기준"을 수립하여 고속철도에 적용하고 있으며, 고속철도 운전취급세칙을 개정하여 지진 발생시 철도의 안전운행을 위한 운전취급 요령에 따라 단계별 열차운행패턴을 구축하여 운영 중이다. 본 연구는 지진가속도계가 설치된 고속철도 인접구간에서 발파작업을 위한 노천 및 터널발파 설계 사례이다.

• 한국산학기술학회논문지
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• 제5권2호
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• pp.186-190
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• 2004

Nano size 몰드의 제작은 X-ray lithography 방법을 이용하여 몰드를 제작하고, micro size의 경우 Deep UV lithography 방법을 이용하여 몰드를 제작하고 있다. 본 연구에서는 SLS(Selective Laser Sintering)형 RP(Rapid Prototyping System)을 이용하여 미세구조 몰드를 제작하였으며, 패턴의 깊이는 400 ㎛까지 구현하였다. 제작된 몰드의 강도와 내열성을 높이기 위하여 전해도금을 이용하여 몰드의 표면에 Ni를 300 ㎛생성 시켰다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권5호
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• pp.362-365
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• 2000

A rapid immunochromatographic assay kit using whole blood to screen hepatitis B surface antigen was developed and evaluated by using sera from 240 patients. The reference diagnosis was based on the results obtained with GENEDIA Anti-HBs Rapid kit which is very similar to the above kit except for the use of serum. The test demonstrated a good correlation with the reference immunochromatographic assay kit, that is, the sensitivity and the specificity of the kit was 100%, respectively. The rapid test kit using whole blood should be more convenient and useful for the diagnosis of hepatitis B virus because the kit does not need machines and time to prepare serum. In addition, this kit is safe from inadvertent infection during sample treatment because the blood is sterilized with hydrogen peroxide, eliminates the procedure required to prepare serum and reduces the possibility of exposure to infectious agents.