• Journal of Korean Society of Transportation
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• v.28 no.6
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• pp.99-108
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• 2010

Due to the recent emergence of global warming concerns, the UN has made the issue of climate change its top priority. Accordingly, Korea has announced a new national master plan titled, 'Participation in global efforts in climate change through -Low Carbon, Green Growth-'. As part of the plan, the constructions of bicycle path networks are being pushed forward. Although the building of bicycle paths and infrastructure is being implemented, little consideration has been given for bicycle path signage. This essay is the study of methodology in the installation of signs on bicycle paths. The research includes a theoretical study of the standard and installation position of signs with consideration of the geometry of bicycles as well issues such as the distance required for the bicyclist to recognize and understand the road sign and to take actions like stopping, In addition, experimental verification of the test results has been carried out. Also, the test on height of signs by changing the installation heights according to a bicyclist's forward vision angle has been conducted.

• Korean Journal of Veterinary Research
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• v.48 no.1
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• pp.53-60
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• 2008

We have investigated efficiency of a recombinant subunit Pasteurella multocida toxin (PMT) that was mixed with a vaccine consisted of inactivated whole cells of Bordetella bronchiseptica, P. multocida (types A and D). For verification of the efficacy of the vaccine, all experimental pigs (suckling piglets, sow and gilts) in the three farms were vaccinated. Antibody titers against B. bronchiseptica and P. multocida type A of the vaccinated pigs by microplate agglutination were significantly higher than those of the control pigs (p < 0.05). Similar patterns were observed in the analysis of anti- PMT neutralizing antibody by serum neutralizing method using Vero cell (p < 0.05). Anti- P. multocida type D antibody titer of the vaccinated sows and gilts by ELISA showed significant differences with those of the non-vaccinated pigs (p < 0.05). Although antibody titers increased, it was unable to find out the difference in the clinical signs between the vaccinated and non-vaccinated pigs. However, the increase in body weight of the vaccinated piglets was observed in comparison with the non-vaccinated piglets on a farm. At slaughtering of the pigs, pathological lesions in the turbinate bones of the vaccinated pigs were significantly lower than those of the non-vaccinated pigs (p < 0.001). These results suggested that efficacy of the vaccine in pigs demonstrated to protect against atrophic rhinitis in Korea.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.26 no.1
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• pp.81-91
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• 2016

Nowadays, electronic device is in a close relationship with human life. Above all, the use of wireless electronic devices such as smart phone, tablet pc, and wireless keyboard is increasing owing to the high convenience and portability. Furthermore, according to the increasing use of sensitive personal and financial information from the electronic device, various attacks for stealing information are being reported. In this paper we do an analysis of 27MHz wireless keyboard vulnerability and set up an analysis environment. Moreover, we make an experiment and show that there are real vulnerabilities. An experimental result will be used for safety analysis and vulnerability verification of wireless electronic devices.

• 한국정보통신설비학회:학술대회논문집
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• 2007.08a
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• pp.427-431
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• 2007

Applications in present-day mobile communication systems particularly require miniaturized dimensions and low-profiles of antenna in order to meet the mobile units. Thus, size reductions and bandwidth enhancements are becoming crucial design considerations for practical applications of microstrip antennas. The motivation of further experiments have been stepped to follow those studies for achieving compact and broadband, even multiplied operation modes, which are greatly increased with much attentions recently. To obtain broadband, single-feed, circularly polarized characteristics of microstrip antennas, a design with feed-line ought to be a factor of two. Usually, diagonally balanced-line feeds with hybrid coupler are employed to attain circular polarizations. We firstly formulated DGS (Defected Ground Structures) based operation principles of the entire microstrip components and therefore were able to derive impedance variance of feed-lines. After verifying corresponding experimental results, we targeted the frequency bands of UHF RFID (Ultra High Frequency Radio Frequency IDentification) and approximately of 0.4-2.4GHz have exhibited remarkable two resonance amplitudes as a dual band antenna. Our secondary researches were aimed to design quad band microstrip antenna which represents four resonance characteristics within the identical frequency bands as well. Microstrip patch has been meandered to lengthen the electrical paths, and the other design criteria with respecting physical parameters including radiation patterns and impedance bandwidths measurements will be described for verification. Advisable applications of these antennas can be GSM850, GSM900, GPS (L1-1575 and L2-1227) and UMTS-2110 of cellular systems, which extremely desire multiband and minimum size.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.4
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• pp.872-878
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• 2012

In this paper, an arm motion sensing system using potentiometer is developed. Most motion sensing systems use optical method for the quality of motion data. The optical method needs much cost for manufacturing capture system and takes much time for correcting the captured data. And mechanical method entails relativity low cost, but it uses the wires and takes much time for correcting the data like the optical method. For solving the problems, in this paper, an arm motion sensing system is newly developed using low cost potentiometer and based on the suggested simple calculation method for the joint angles and the angular velocities. For the verification of the performance of the developed system, practical experiments were executed using real human arm motion and a robot arm. The experimental results showed that the motion of the robot arm controlled by the output of the developed motion sensing system is much similar with the motion of human arm.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.06a
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• pp.103-104
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• 2014

Wide Area Differential GNSS(WA-DGNSS) was developed in order to improve the accuracy and integrity performance of GNSS. In Korea, WA-DGNSS development project, which aims to develop core algorithms and verify the performance using pseudolite-based demo system, is currently in progress. In this paper, overall structure of developed system and experimental methods which enables the post-processing test with commercial receiver will be described. In this system, pseudolite is used to broadcast augmenting signal and RF signal logger and broadcaster were used to test the performance. Performance test was conducted broadcasting the logged RF signal and pseudolite signal to commercial receiver and those results will be described.

• KIISE Transactions on Computing Practices
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• v.22 no.3
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• pp.119-126
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• 2016

In this study, we verified the feasibility of a Korean morphological analyzer that uses a pre-analyzed Eojeol dictionary and syllable-based probabilistic model. For the verification, MACH and KLT2000, Korean morphological analyzers, were cloned with a pre-analyzed eojeol dictionary and syllable-based probabilistic model. The analysis results were compared between the cloned morphological analyzer, MACH, and KLT2000. The 10 million Eojeol Sejong corpus was segmented into 10 sets for cross-validation. The 10-fold cross-validated precision and recall for cloned MACH and KLT2000 were 97.16%, 98.31% and 96.80%, 99.03%, respectively. Analysis speed of a cloned MACH was 308,000 Eojeols per second, and the speed of a cloned KLT2000 was 436,000 Eojeols per second. The experimental results indicated that a Korean morphological analyzer that uses a pre-analyzed eojeol dictionary and syllable-based probabilistic model could be used in practical applications.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.1
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• pp.5-13
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• 2017

Polypropylene is the main existing material in the domestic market being used for the filter plate because of its moldability, low cost, and commercial availability. Polypropylene filter plate once distorted due to the high-pressure during operation may cause the problem in the continuous operation of the solid-liquid separation module. Thermoplastic Poly Urethane (TPU) can be a high-performance alternative material for the filter plate in the solid-liquid separation module of the dehydration process. Hence, to predict and evaluate the TPU for structural stability in the filter plate through analytical techniques designed and experimental verification is essential. As a result, TPU filter plate had maximum strain of 27.85 MPa at 20 bar pressure condition. This result is less than TPU stress-strain limit, which ensures the structural stability of the TPU material.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.2
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• pp.106-113
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• 2018

The Intense acoustic wave generated by the jet flame at the lift-off causes the vehicle to vibrate in the form of acoustic loads. The DSM-II(Distributing Source Method-II), which is a representative empirical acoustic loads prediction method, is a method of distributing a noise source along a jet flame axis and has advantages in calculation cost and accuracy. However, due to the limitation of the distributing method, there is a limit to accurately reflect the various launch pad configurations. In this study, acoustic loads prediction method which can freely distribute noise sources is studied. by introducing NURBS(Non-Uniform Rational B-Spline) modeling into empirical prediction method. For the verification of the newly introduced analytical technique of the NURBS, the acoustic loads prediction for the Epsilon rocket's low-noise launch pad shape was performed and the results of the analysis were compared with the existing prediction methods and experimental results.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.7
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• pp.527-534
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• 2018

The endurance of the multi-copter is one of the important variables that determine the mission performance. Therefore, accurate endurance should be defined as essential for performing effective missions. In this paper, we present the results of the study on the flight performance of the aircraft, especially the hovering of the drone(multi-copter). Unlike conventional aircraft, which consider aerodynamic performance by the fuselage, the multi-copter is mostly determined by the propulsion system. Therefore, the research method classifies the various parts constituting the drone system into functions, analyzes the performance of the unit parts and obtains the experimental data by sorting out the specifications and functions at the component level and mathematical formulation, The results of this study are as follows. In addition, the 5kg class quad copter was used to predict and verify the voltage change with endurance through analysis of in situ flight. By predicting endurance under various conditions, it can help design/build the right Multi-copter for mission.