• Bulletin of the Society of Naval Architects of Korea
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• v.14 no.3
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• pp.5-12
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• 1977

In shipyard production processes, lots of steel plates are assembled by welding. Some rectangular steel plates are buttwelded to build a large block in panel production lines. There are some advantages to take the tandem arc welding in butt joints of rectangular plates with respect to welding speed. Hence, the thermal stresses and the temperature distribution of the tandem arc welding are studied in this paper. The solutions in the case of the infinite plate with two instantaneous point heat sources have been obtained. And then the solutions have been extended to the case of two moving heat sources corresponding to the tandem arc welding with the aid of Duhamel's superposition integral. It was found that the temperature distribution was good agreement with the results of the experiments by Rosenthal and Park and the thermal stresses calculated were acceptable with respect to a physical phenomenon. These solutions are able to be applied to the problem such as a line heating.

• Korean Management Science Review
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• v.17 no.3
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• pp.147-160
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• 2000

These days, a modeling tool or environment has to know about the others on the market and build bridges to them with which their customers insist on sharing models and data. When it is based on a closed architecture, a tangle of import/export point translators is required. Using an exchange standard, we can design an open architecture for the interchange of models and data. XML(Extensible Markup Language) provides a framework for describing the syntax for creating and exchanging data structures. The explosive growth of XML-based business proposals and standards reflects the urgent requirements and its strength. This paper proposes an XML-based language for sharing decision models within the MSOR/DSS community. The language is able to allow applications and on-line analytic processing tools to models obtained from multiple sources without having to deal with individual differences between those sources. It is expected to be a medium for B2B integration by supporting flexible interchange of decision models.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.3
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• pp.292-299
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• 2013

The measurement in the manufacturing process of curved ship hull plates still depends on wooden templates as a standard instrument. The metrology-enabled automation in the shipbuilding process has been challenged instead of line measurement with wooden templates. The developed measurement system consists of a CCD camera, multiple structured laser sources and 3-DOF motion device. The system carries out measurement of curved profiles for large scale plates by an optical triangulation method. The results of experiment conducted in a manufacturing shop demonstrate the accurate and robust performance.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.149-152
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• 1999

This paper addresses major issues in localising sound sources in space using the experimental data set of head-related responses in the time or frequency domain. They come from the technical realisation steps for implementing the convolution of HRIR's with sound sources, the cross-talk cancellation for transaural filtering, the matched time delay compensation, etc. in real, those technical matters seem to be minor because they can be realised in off-line signal processing schemes. This paper puts much emphasis on what we misunderstood about the sets of HRTF's or HRIR's, More specifcaily, the sets of HRTF's or HRIR's of course supply relevant information to sound localisation but include much useless 'rubbish' that have made for us to fail to put spatial image into real souno signals such as voices and music's. This paper proposes possible reasons for such failure and, furthermore, introduces detained subjects that should be challenged so as to resolve them.

• Journal of the Korean Chemical Society
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• v.7 no.4
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• pp.288-292
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• 1963

The rates of reaction of various Korean anthracites with carbon dioxide were measured at temperatures ranging from $850^{\circ}C$ to $1100^{\circ}C$ with coal -6, +8 sieve size and the residence time of reactant gas in the fixed coal bed 14.0 to 15.0 seconds. The primary variables studied were the coal sources and temperature. The reactivity was considerably varies with the coal sources and the general trends show that the reactivity sharply increases with increasing reaction temperature except the Yongwol coal where the increase is not so sharp, which is considered to be due to high reactivity and high-pore structure of the coal. It was also found that a straight line was produced when a logarithm of the rate constant is plotted against the reciprocal of the absolute temperature up to 1000^${\circ}C$, but above that temperature it deviates from linearity. The information obtained will be of value in the design of the coal gasifier using Korean anthracites.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.1173-1177
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• 1990

Cerebellar Model Linear Associator Net(CMLAN), a kind of neuro-net based adaptive control function generator, was applied to the problem of direct inverse calibration of three and six d.o.f. POMA 560 robot. Since CMLAN autonomously maps and generalizes a desired system function via learning on the sampled input/output pair nodes, CMLAN allows no knowledge in system modeling and other error sources. The CMLAN based direct inverse calibration avoids the complex procedure of identifying various system parameters such as geometric(kinematic) or nongeometric(dynamic) ones and generates the corresponding desired compensated joint commands directly to each joint for given target commands in the world coordinate. The generated net outputs automatically handles the effect of unknown system parameters and dynamic error sources. On-line sequential learning on the prespecified sampled nodes requires only the measurement of the corresponding tool tip locations for three d.o.f. manipulator but location and orientation for six d.o.f. manipulator. The proposed calibration procedure can be applied to any robot.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.244-250
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• 2007

The electric train in the first line subway runs faster in the block from Suwon to Cheonan than the general block. The faster run results in the deterioration of ride quality due to the increase of noise and vibration. To reduce the noise and vibration of the electric train, a running test of the electric train was performed in the block from Suwon to Cheonan. The experimental results show that the sources of the noise and vibration basically comes from the irregularity of the railroad track and the connection part between car body and bogie. The possible countermeasure of the high speed electric train can be the reinforcement of the center pivot to have more flexibility and the frequent maintenance of electric train.

• Journal of Environmental Health Sciences
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• v.28 no.2
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• pp.1-9
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• 2002

This study was performed to investigate vibration generated from machines that were used at factories and construction works. Vibrations were measured at three points in a straight line based on distance from the vibration sources, and analyzed to assess the vibration bevels. The average vibration level of factory machines was 65.4dBV at 2m, and that of construction machines was 74.0dBV at 5m. Vibration attenuations was 4.0~8.2dBV by double distance. All such data were applied to gain coefficients of attenuation equations for predicting vibration level by distance from the vibration sources. Data recorded on tapes were analyzed to understand the characteristics of frequency because these characteristics are important factors to design a Plan for installing the vibration-Proof devices. Finally, considering results from these analysis, assessment, and prediction, the methods for reducing vibration generated from machines were discussed.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.6
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• pp.813-826
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• 1999

To understand the present status of air pollutant emission data for the greater Seoul area, existing air pollutant emission data were analyzed and compared. For the criteria pollutants, estimation methods of emissions from point, line, and area sources adopted in the previous studies were analyzed and their results were compared. Two sets of VOC emission estimation were also compared and analyzed. There exists a large discrepancy among previous emission data due to the differences in the scope of emission sources and the estimation method including emission factors employed in each estimation. Applications of previous air pollutant emission studies for air quality modeling and related problems were discussed.

• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.275-281
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• 1993

The new high temperature plasma source for spectrochemical analysis has been developed and characterized. In the development of new high temperature plasma sources for atomic emission spectrocopy, optimization of experimental variables is necessary to achieve the best analytical results. By means of a modified sequential simplex optimization method, six experimental variables were optimized. The line-to-background (L/B) ratio for Ca(II) at 393.37 nm was used as measure of the response function. The optimal experimental conditions were found to be at a current of 27.8 A, a plasma length of 28.8 mm, a sample uptake rate of 1.3 ml/min, a sample carrier gas flow rate of 0.7 ml/min, a plasma gas flow rate of 4.9 l/min, and an observation height of 6.4 mm above the top quartz tube.