• Fire Science and Engineering
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• v.28 no.5
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• pp.1-7
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• 2014

The present study has been conducted to analyse the effects of various pool diameters on the measurement of heat release rate (HRR) of heptane fire using large scale cone calorimeter (LSC). The burning rate which is the major parameter for HRR compared with the previous model suggested by A. Hamins. The combustion efficiency for heptane by oxygen consumption method is about 91%, which is almost same with the previous results of 92% suggested by J. Gore. The convective HRR by enthalpy consumption method was 54% lower than HRR by oxygen consumption method. This results are practical use for establishing the reliability of heat release rate for fire experiment.

• Journal of Welding and Joining
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• v.19 no.2
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• pp.200-207
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• 2001

Three-diemnsional bead profile was measured using the biprism stereo vision sensor in GMAW, which consists of an optical filter, biprism and CCD camera. Since single CCD camera is used, this system has various advantages over the conventional stereo vision system using two cameras such as finding the corresponding points along the horizontal scanline. In this wort, the biprism stereo vision sensor was designed for the GMAW, and the linear calibration method was proposed to determine the prism and camera parameters. Image processing techniques were employed to find the corresponding point along the pool boundary. The ism-intensity contour corresponding to the pool boundary was found in the pixel order and the filter-based matching algorithm was used to refine the corresponding points in the subpixel order. Predicted bead dimensions were in broad agreements with the measured results under the conditions of spray mode and humping bead.

• Journal of Ocean Engineering and Technology
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• v.24 no.2
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• pp.74-81
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• 2010

Ship STEP is the international standard for the exchange of ship modeling data between heterogeneous systems. It is expected that STEP AP218 can be used for seamless data exchange between various CAD/CAM/CAE systems used in the shipbuilding design process. Although the conformance assessment for standards would maximize the performance and confidence about data exchanges, most research has been directed toward interoperability testing. ISO SC4/TC184 only provides the method for conformance testing, and it can be used with test cases on application protocols. Even though standards have been defined for conformance assessment and testing, there is no organization or association. CAD vendors have focused on interoperability testing for evaluation of the performance of their systems. In this paper, the conformance testing criteria for AP218 have been developed with abstract test cases of ship structures. The requested STEP translator was also reviewed with a developed item pool of testing criteria. The criteria methodology would be a guideline for the development of translators and interfaces. The item pool method of testing criteria for conformance assessment would increase performance and efficiency of data translators for Ship STEP and other standards.

• Journal of the Korean Institute of Gas
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• v.2 no.1
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• pp.14-22
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• 1998

In this work, in order to quantitatively predict the radiation flux and propose an idea about how to reduce the radiation damage, the radiation flux caused by pool fire of an LNG storage tank has been calculated using the RISC (Risk and Industrial Safety Consultant) proposed model under various conditions. Model predictions showed that the most important parameter affecting the radiation flux by the LNG pool fire is the wind speed. The extent of radiation damage to a target from fire flame was more significant with variation of wind speed at a low wind speed than with that at a high wind speed. It was found that the radiation damage by the former is substantially reduced with planting windbreak system around the plant. Since the windbreak is most economical than any other method, it is strongly suggested to plant a tree belt in the factory surroundings, especially near by the area of gas storage facilities, linking with water cooling and fire protection systems.

• The Korean Journal of Nuclear Medicine Technology
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• v.12 no.3
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• pp.192-198
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• 2008

Purpose: The scan time reduction helps to yield more accurate results and induce the minimization of patient's motion. Also we can expect that satisfaction of examination will increase. Nowdays medical equipment companies have developed various programs to reduce scan time. We used Onco. Flash (Pixon method, SIEMENS) that is an image processing technique gated cardiac blood pool scan and going to evaluate its clinical usefullness. Materials and Method: We analyzed the 50 patients who were examined by gated blood pool scan in nuclear medicine department of Asan Mediacal Center from June $20^{th}$ 2008 to August $14^{th}$ 2008. We acquired the Full-time (6000 Kcounts) and Half-time (3000 Kcounts) LAO image in same position. And we acquired LVEF values ten times from Full-time, Half-time images acquired by the image processing technique and analyzed its mean and standard deviation values. To estimate LVEF in same conditions, we set automatic location of the LV ROI and background ROI based on same X and Y-axis. Also we performed blinding tests to physician. Results: After making a quantitative analysis of the 50 patients EF values, each mean${\pm}$standard deviation is shown at Full-time image $68.12{\pm}7.84%$, Half- time (acquired by imaging processing technique) $68.49{\pm}8.73%$. In the 95% confidence limit, there was no statistically significant difference (p>0.05). After blinding test with a physician for making a qualitative analysis, there was no difference between Full-time image and Half-time image acquired by the image processing technique for observing LV myocardial wall motion. Conclusion: Gated cardiac blood pool scan has been reported its relatively exact EF measured results than ultrasound or CT. But gated cardiac blood pool scan takes relatively longer time than other exams and now it needs to improve time competitive power. If we adapt Half-time technique to gated cardiac blood pool scintigraphy based on this study, we expect to reduce possible artifacts and improve accessibility as well as flexibility to exam. Also we expect patient's satisfaction.

• The Journal of the Acoustical Society of Korea
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• v.21 no.2
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• pp.182-189
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• 2002

In this paper, we research the content-based analysis and classification according to the composition of the feature parameters pool for the auditory signals to implement the auditory indexing and searching system. Auditory data is classified to the primitive various auditory types. we described the analysis and feature extraction method for the feature parameters available to the auditory data classification. And we compose the feature parameters pool in the indexing group unit, then compare and analysis the auditory data centering around the including level and indexing criterion into the audio categories. Based on this result, we composed the classification procedure and simulate the auditory data classification.

• KIPS Transactions on Computer and Communication Systems
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• v.6 no.9
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• pp.385-396
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• 2017

Many IoT platforms have been proposed for various IoT devices, from low-end to high-end performance. We previously proposed a new IoT platform called MinT that supports the operation of the sensing devices and network communication. In the proposed platform, the things can flexibly connect to each other and efficiently share their information. Most IoT platforms, including the MinT, support thread pooling to quickly process requests. However, using a thread pool with a fixed thread count can cause network delay and inefficient energy consumption. In this paper, we propose an enhanced method to manage the thread pool efficiently by adjusting the number of threads every cycle to regulate the device's performance. In particular, we aim to improve the performance of the Interaction Thread Pool Group, which is responsible for analyzing, processing, and re-transmitting the received packets. The experiment shows that the improved method increases the average throughput by approximately 25% compared to the existing platforms. Finally, using the proposed method, the MinT can reduce the transmission delay and energy consumption of devices in the IoT environment.

• Journal of Advanced Marine Engineering and Technology
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• v.30 no.1
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• pp.102-108
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• 2006

On the refutation demanded for a control of various toxic substances. PCBs(poly chlorinated biphenyl) has a fatal poisonous matter in the ecosystem and the environmental pollution as it Is a kind of stable chemical substance. Especially, the gross Product of PCBs is estimated at about one million tonnage all over the world. However it is kept on storing in untreated state, then has a deterioration by the Prolonged storage and a risk of overflowing. Therefore, this research examined the fundamental characteristics of combustion and emission for the target of using the IPA (iso-propyl alcohol) solution as a part of PCBs control. IPA was filled to three kinds of Vessel, i.e. Vessel I, II, and III, and then was investigated as follows combustion shape, flame temperature. mass burning velocity, and PM(Particulate matter). A radial thermometer and a C-A thermocouple measured the flame temperature, and the optical extinction method by using He-Ne laser and the filter weight method used in the PM measurement. As a result, with an increasing of L/S ratio, the flame length become shorter and the burning velocity is more rapid, but the particulate matters is higher. It is supposed that the air flow rate is high on Vessel. and then the combustion is Promoted in the surface area of the upstream zone. The future works plan to investigate the characteristics with an using of the mixing of IPA and PCBs

• Journal of Ocean Engineering and Technology
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• v.27 no.5
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• pp.43-50
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• 2013

In the present investigation, the hydrodynamic characteristics of a vertically floating hollow cylinder in regular waves have been studied. The potential theory for solving the diffraction and radiation problem was employed by assuming that the heave response motion was linear. By using the matched eigenfunction expansion method, the characteristics of the exciting forces, hydrodynamic coefficients, and heave motion responses were investigated with various system parameters such as the radius and draft of a hollow cylinder. In the present analytical model, two resonances are identified: the system resonance of a hollow cylinder and the piston-mode resonance in the confined inner fluid region. The piston resonance mode is especially important in the motion response of a hollow circular cylinder. In many cases, the heave response at the piston resonance mode is large, and its resonant frequency can be predicted using the empirical formula of Fukuda (1977). The present design tool can be applied to analyze the motion response of a spar offshore structure with a moon pool.

• Journal of Digital Convergence
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• v.8 no.1
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• pp.41-53
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• 2010

In this paper, we discuss patent pool and a patent valuation scheme for fair royalty distribution among the patents in a pool. In the knowledge-based economy, intellectual capital-the accumulation of technology and know-how-is recognized as the most important source of company's competitive advantage and economic growth. By providing exclusive rights to patent holders, the patent system aims to encourage innovation-invention & commercialization of new technologies-in order to raise the standard of living. However, drawbacks of patent system, which occur as the number of patents issued increases rapidly and patent ownership is fragmented, may slow down the innovation efforts seriously. A promising solution is the patent pool approach, which was for instance employed by the U.S. congress during World War I to free the airplane manufacturers from the patent tangle by letting them license all the patents for a fee. It is necessary to figure out relative technological contribution of patent for fair distribution of royalty revenues among patent holders. The Rating/Ranking Method seems to fit to that valuation purpose. We examined technology valuation models from various organizations and selected a set of more influential valuation factors which can be incorporated as scoring criteria in the Rating/Ranking Method.