• Proceedings of the Korean Information Science Society Conference
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• 2002.10e
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• pp.151-153
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• 2002

Mobile handhold devices such as PDA(Personal Digital Assistant) and Cellular Phone are more and more popular for personal web surfing. But today, most mobile handheld devices have relatively poor web browsing capability because of the small bandwidth of wireless connection, the small speed of CPU, the small capacity of RAM and Flash ROM, the small display size of LCD and the short lifecycle of battery. Users have to endure bigger communication latency than Desk PC's one because of these factors. In this paper, we propose an effective pre-refresh mechanism for handheld device's embedded web browser so as to make user's web surfing faster. The experiment was done using the simulator designed by ourselves and the experiment result demonstrates the proposed mechanism has a good performance to make web surfing faster.

• Journal of the Korea Safety Management & Science
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• v.7 no.4
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• pp.85-99
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• 2005

The main objective of this paper is to search whether containment vessel's best pressure may increase until how long when loss of coolant accident (LOCA) happened in containment vessel of Ulchin nuclear power plant 1 and 2. Another goal of this research is to find the influential factors that increase containment vessel pressure. Model for this research is Ulchin nuclear power plant 1 with 10 cycles. Data were collected by simulator of Ulchin nuclear power plant 1 and design of experiment was used for data analysis. For the experiment, seven factors that are going to influence in containment vessel pressure were chosen. It was found that fatter which influences in early rise of containment vessel pressure after LOCA is only explosion size. Also, containment vessel's best pressure (3.74 bar.a) was much lower than limit (4.86 bar.a) of FSAR (Final Safety Analysis Report).

• Journal of Korean Institute of Industrial Engineers
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• v.22 no.3
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• pp.399-412
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• 1996

With respect to the effects of types of knowledge on human diagnostic performance, the results of several experiments claimed that training with procedural knowledge is more effective than training with principle knowledge. However, more useful results would be attained by investigating when and how the principles of system dynamics is valuable for diagnosis. Accordingly, we conducted an experiment to reevaluate the value of principle knowledge in two problem situations. A simulator system, named DLD, to diagnose an electronic device was created. It is a context-free digital logic circuit which includes forty-one gates of three basic types. The experiment investigated the effects of principle knowledge over common procedural knowledge. The experimental results showed that the effects of principle knowledge is dependent on the complexity of diagnostic situations. This adds up on experimental evidence against the presumed ineffectiveness of principle knowledge and forward reasoning in fault diagnosis. The results also suggest the source of the usefulness of principle knowledge.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.24 no.68
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• pp.31-36
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• 2001

Prior to the Independent Visual Background(IVB) luminance control experiment, we studied that IVB could reduce the simulator sickness depending on subject＇s knowledge about the IVB (expectation group) or non-IVB (no expectation group). As results of experiments from 12 subjects, expectation group＇s RSSQ scores were similar, no matter IVB was present or not. However, non-expectation group＇s RSSQ scores were lower when the IVB were present. The result from this experiment confirms the findings of Duh (2001), that an IVB may alleviate SS. However this effect was found only at the expectation group. Failure to replicate Duh＇s results could be due to several factors, such as individual differences in response to the IVB and the low number of subjects (n=6) in the no expectation group.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.10
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• pp.130-135
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• 2010

In this paper, the shading ratio about to output the minimum critical power of a photovoltaic panel was determined by experiment and simulation. A 2.475[kW] poly-crystalline photovoltaic panel consisting of 11 modules was used in the experiment and its surface was covered with shading curtains, thus the amount of light incident to the modules were controlled. In order to compare with the experimental results, the experimental circuits were modelled with the CASPOC (power electronics electrical drives simulator) and module parameters were applied to it, by which the minimum critical power was calculated. As a result, the photovoltaic panel was about to generate the power when the 5th shading curtains were removed from the module surface, after then the output power linearly increased by removing the shading curtains. In addition, the CASPOC simulation results were similar to the experimental results in the abrupt decreasing pattern of power.

• Journal of Ocean Engineering and Technology
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• v.29 no.6
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• pp.488-498
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• 2015

This paper presents the dynamic model of an AUV called HW200 for underwater surveillance. The mathematical model of HW200 is briefly introduced, considering its shape. The maneuvering coefficients were initially estimated using empirical formulas and a database of vehicles with similar shapes. A motion simulator, based on Simulink of Mathworks, was developed to evaluate the mathematical model of the vehicle and to tune the maneuvering coefficients. The parameters were finely tuned by comparing the experimental results and simulated responses generated with the simulator by applying the same control inputs as the experiment. The velocity of HW200 in the tuning process was fixed at a constant forward speed of 1.83 m/s. Simulations with variable speed commands were conducted, and the results showed good consistency in the motion response, attitude, and velocity of the vehicle, which were similar to those of the experiment even under the speed variation. This paper also discusses the feasibility of its application to a model-based integrated navigation system (INS) using the auxiliary information on the velocities generated by the model.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.9
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• pp.769-774
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• 2016

Epoxy polymer exposed to solar radiation on long-term is required to a long-term environmental test in order to ensure the reliability of operation performance. In this paper, the solar aging experiment is performed for 7, 14, 28, 56, and 84 cycles, using solar simulator designed according to MIL-STD-810. After the aging experiment, measuring RGB values and using the CIE1976 color space, each RGB decreasing rates and total color shift are calculated. In addition, using a universal testing machine, mechnical properties according to ASTM-D638 are measured. As a result, by increasing solar aging period, total color shift is increased, and the tensile strength and elongation are decreased, but the elastic modulus and the poisson's ratio are slightly changed.

• The Journal of the Convergence on Culture Technology
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• v.5 no.1
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• pp.361-369
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• 2019

With the commercialization of the ADAS functions, the need for the experience of the autonomous driving system is increasing, and the role of the artificial intelligence agent is attracting attention. This study is an autonomous driving experience experiment that verifies the effect of self-efficacy and agent embodiment. Through a simulator experiment, we measured the effect of existence of self-efficacy and agent embodiment on social presence, perceived risk, and perceived ease of use. Results show that self-efficacy had a positive effect on social presence and perceived risk, and agent embodiment negatively affected perceived ease of use. Based on the results of the study, we proposed guidelines for agent design that can increase the acceptance of the semi-autonomous driving system.

• Design Convergence Study
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• v.17 no.4
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• pp.17-29
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• 2018

In the semi-autonomous vehicle, before reaching a fully autonomous driving stage, it is imperative for the system to issue a take-over request(TOR) that asks a driver to operate manually in a specific situation. The purpose of this study is to compare whether head-up display(HUD) is a better human-vehicle interaction than head-down display(HUD) in the event of TOR. Upon recognition of TOR in the experiment with a driving simulator, participants were prompted to switch over to manual driving after performing a secondart task, that is, playing a game, while in auto-driving mode. The results show that HUD is superior to HDD in 'ease of use' and 'satisfaction' although there is no significant difference in reaction time and subjective workload. Therefore, designing secondary tasks through HUD during autonomous driving situation improves the user experience of the TOR function. The implication of this study lies in the establishing an empirical case for setting up UX design guidelines for autonomous driving context.

• Journal of the Korea Society for Simulation
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• v.22 no.4
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• pp.11-19
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• 2013

The Korean naval weapon systems, combat experiments establish the concept of Battle operations, and create the future of the new weapons system. Doctrine development and training as well as ranging from experiments for evaluate the performance of mission operations for combat experiments are used. The battle lab is effectively support tool for the Korean Naval battle experiments. The battle lab is through a dedicated testing facility and to build efficient and effective simulation-based acquisition supporting environment. In this paper, the ship / submarines C2 operations virtual simulator was developed to support the concept of Battle operations of naval combat experiments in training and tactical development. The ship C2 operations virtual simulator makes the anti-ship and anti-aircraft the engagement scenario for performed experiments using the SADM. The submarines C2 operations virtual simulator makes the anti-submarine engagement scenario for performed experiments using EAS. EAS System was created before reuse. EAS system by modifying the additional interfaces HLA-RTI has been reused. Reflected in the tactics and training after analysis of the results through the battle experiment. Also increase training fidelity through operator involvement. The anti-ship and anti-aircraft system architecture (SADM) and anti-submarine system architecture (EAS) requires unique design of system framework since two separate architectures should be integrated into a system. An C2 virtual linked architecture was used to integrate different system architecture. A C2 virtual linked software framework, designed that have integrated protocol for battle experimental linkage and battlefield visualization environment.