• Journal of the HCI Society of Korea
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• v.7 no.1
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• pp.19-28
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• 2012

Why people share location context information? The purpose of our study is that why users share location context information and which factors is related to co-experiences in LBSNS. Through an exploratory approach, first, we conducted a qualitative study in order to understand experiences among people in LBSNS and analyzed according to Grounded Theory. As a result, we found concepts regarding co-experiences cooperatively and competitively in LBSNS. Second, the theoretical model of co-experience was constructed by mediating perceived empathy based on theoretical foundation. In this study, theoretically, we suggested exploratory research model of co-experiences in LBSNS. Practically, designers could adopt concepts in terms of competition and collaboration among users to build co-experience of LBSNS services as its guidelines.

• Nuclear Engineering and Technology
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• v.51 no.1
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• pp.155-162
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• 2019

To reduce the secondary damage caused by leakage accidents in plant piping systems, a constant surveillance system is necessary. To ensure leaks are promptly addressed, the surveillance system should be able to detect not only the leak itself, but also the location of the leak. Recently, research to develop new methods has been conducted using cameras to detect leakage and to estimate the location of leakage. However, existing methods solely estimate whether a leak exists or not, or only provide two-dimensional coordinates of the leakage location. In this paper, a method using multiple cameras to detect leakage and estimate the three-dimensional coordinates of the leakage location is presented. Leakage is detected by each camera using MADI(Moving Average Differential Image) and histogram analysis. The two-dimensional leakage location is estimated using the detected leakage area. The three-dimensional leakage location is subsequently estimated based on the two-dimensional leakage location. To achieve this, the coordinates (x, z) for the leakage are calculated for a horizontal section (XZ plane) in the monitoring area. Then, the y-coordinate of leakage is calculated using a vertical section from each camera. The method proposed in this paper could accurately estimate the three-dimensional location of a leak using multiple cameras.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1610-1613
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• 2002

This paper analyses the performance of PE-IPDL technique fer the wireless mobile position location, which have been considered as a major candidate for 3GPP position location due to its capability in mitigating the hearability problem and DOP problem. To improve the location performance of PE-IPDL, this paper introduces the high-resolution estimation technique for the first arrival multipath delay, and simulation results verify its superiority. For a systematic analysis of above location method, its performances are exploited by obeying the CODIT channel model specially bad urban channel environment. Simulation results verify its efficiency of enhancing the degree of accuracy in positioning.

• Fire Science and Engineering
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• v.17 no.4
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• pp.28-35
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• 2003

To analyze the transfer characteristics of $CO_2$ extinguishant when extinguishant is injected into a closed space similar to a marine engine room, a numerical simulation was performed. Flow and Concentration fields are calculated according with the variation of the fire plume,s location. The results show that tile variation of fire plumes, location greatly effected on the flow patterns and the characteristics of $CO_2$ extinguishant transfer. In case of the fire plume located at left region of the 2nd floor center in the engine room consisted of first and second floor, The effects similar to the air curtain is found and cut off the mass transfer. In the characteristics with hight, the iso-concentration line below the extinguishable limit is formed in the left region of the 1st and 2nd floor center after the $CO_2$ extinguishant is completely injected. therefore I think that the results of this study are considered to arrange the $CO_2$ injection nozzles for the $CO_2$ fire fighting equipments.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.12
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• pp.1053-1058
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• 2016

The eLoran(enhanced Long Range Navigation) transmitting antenna is analyzed for co-location with an AM transmitting antenna in an MF transmitting site. To compensate for the loading effect, the umbrella-type loading is applied for eLoran antenna. The validity of the co-location between the MF antenna and the eLoran antenna is verified through the simulation results of the radiation pattern and the return loss. Also, coupling including antenna matching circuit is analyzed to verify the effect of the transmitting circuit. The coupling between the LF and eLoran antenna is -53.3 dB at 100 kHz and -64.8 dB at 1,053 kHz, respectively.

• 한국연소학회:학술대회논문집
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• 2012.04a
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• pp.199-200
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• 2012

An experimental study on geometric optimization was conducted to develop a hybrid/dual swirl jet combustor for a micro-gas turbine. A hybrid concept indicating a combination of swirling jet partially premixed and premixed flames were adopted to achieve high flame stability as well as clean combustion. Location of pilot nozzle, angle and direction of swirl vane were varied as main parameters with a constant fuel flow rate for each nozzle. The results showed that the variation in location of pilot nozzle resulted in significant change in swirl intensity due to the change in flow area near burner exit, and thus, optimized nozzle location was determined on the basis of CO and NOx emissions under conditions of co-swirl flow and swirl $angle=30^{\circ}$. The increase in swirl angle (from $30^{\circ}$ to $45^{\circ}$) enhanced the emission performances, in particular, with a significant reduction of CO emission near lean-flammability limit. It was observed that the CO emission near lean-flammability limit was further reduced through the counter-swirl flow. However, there was not significant change in the NOx emission in the operating conditions (i.e. equivalence ratio of 0.6~0.7) between the co- and the counter-swirl flow.

• Special Issue of the Society of Naval Architects of Korea
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• 2008.09a
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• pp.33-37
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• 2008

The evidence of the Cargo tank volume is very important between Buyer and Seller for agreement each other for LNG Ship. CTS(Custody Transfer System) Radar type level gauging sensor to be measured for cargo volume. The data of Trim & List sensor to be compensated for measuring data which is original data of the CTS sensor. The latest days, the Buyer would have posed a problem both the location and the accuracy of trim/list sensor specially neared final stage of the ship's delivery. So, we would like to report the introducing to the trim/list sensor and the confirmation of actual location for the trim/list sensor.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.06a
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• pp.310-311
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• 2011

In this paper, refer to necessity about independent navigation system for back up of GPS by LORAN-C and suggest a solution of Co-location modeling of LORAN-C with DGPS and analysing for the interference.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.3
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• pp.498-504
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• 2015

This paper proposed an Spread Spectrum Time Domain Reflectometry (SSTDR) using time-frequency correlation analysis in order to have more accurate fault determination and location detection than classical SSTDR despite increased signal attenuation due to the long distance to cable fault location. The proposed method was validated through comparison with classical SSTDR methods in open- and short-circuit fault detection experiments of low-voltage power cables. The experimental results showed that the proposed method can detect correlation coefficients at fault locations accurately despite reflected signal attenuation so that cable faults can be detected more accurately and clearly in comparison to existing methods.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.974-975
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• 2005