• Journal of Korea Game Society
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• v.17 no.3
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• pp.53-62
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• 2017

VR content manipulation equipment is not easy for individuals to access because it requires high prices. Especially, in the case of a system for tracking the motion of the user among the VR contents, a separate optical sensor device using an infrared camera is generally used. The disadvantage of the optical sensor equipment is that the measurable range is dependent on the measurement direction when tracking the rotation motion when using only a single device. In order to solve the above problems, this paper shows that the inertial sensor of the smartphone, which is generally owned by the public, can track the rotational motion of the user regardless of the measurement direction . The system using the LeapMotion is used as the reference system, and the system using the smart phone is defined as the evaluation system, and the usability of the evaluation system is verified by comparing the user satisfaction of the two systems.

• Archives of Pharmacal Research
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• v.25 no.2
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• pp.143-150
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• 2002

Fluorescent probes bound to DNA typically display nanosecond decay times and reveal only nanosecond motions. We extend the time range of measurable DNA dynamics using $[Ru(pby)_2(dppz)]^{2+}$ (bpy=2.2'-bipyridine, dppz=dipyrido[3,2-a2',3'-c]phenazine) (RuBD) which displays a mean lifetime near 90 ns. To test the usefulness of RuBD as a probe for diffusive processes in calf thymus DNA, we compared the efficiencies of fluorescence resonance energy transfer (FRET) using three donors which display lifetimes near 5 ns for acridine orange (AO), 22 ns for ethidum bromide (EB) and 92 ns for RuBD, with nile blue (NB) as the acceptor. The F rster distances for AO-NB, EB-NB and RuBD-NB donor-acceptor pairs were 42.3, 52.3, and $30.6{\;}{\AA}$, respectively. All three donors showed dramatic decreases in fluorescence intensities and more rapid intensity decays with increasing NB concentrations. The intensity decays of AO and EB in the presence of varying concentrations of NB were satisfactorily described by the one-dimensional FRET model without diffusion (Blumen and Manz, 1979). In the case of the long-lifetime donor RuBD, the experimental phase and modulation somewhat deviated from the recovered values computed from this model. The recovered NB concentrations and FRET efficiencies from the model were slightly larger than the expected values, however, the recovered and expected values did not show a significant difference. Thus, it is suggested that the lifetime of RuBD is too short to measure diffusive processes in calf thymus DNA.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.6
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• pp.4108-4114
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• 2015

An image acquisition by using an optical mirror is called as a catadioptric method. The catadioptric imaging method is generally used for acquisition of 360-degree all directional visual information in an image. An exemplar omnidirectional optical mirror is the bowl-shaped hyperbolic mirror. In this paper, a single camera omnidirectional stereo imaging method is studied with an additional concave lens. It is possible to obtain 3 dimensional coordinates of environmental objects from the omnidirectional stereo image by matching the stereo image having different view points. The omnidirectional stereo imaging system in this paper is cost-effective and relatively easy for correspondence matching because of consistent camera intrinsic parameters in the stereo image. The parameters of the imaging system are extracted through 3-step calibration and the performance for 3-dimensional coordinates reconstruction is verified through experiments in this paper. Measurable range of the proposed imaging system is also presented by depth-resolution analysis.

• Journal of Biosystems Engineering
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• v.41 no.3
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• pp.263-272
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• 2016

Purpose: Pulse crop damage due to wild birds is a serious problem, to the extent that the rate of damage during the period of time between seeding and the stage of cotyledon reaches 45.4% on average. This study investigated a method of fundamentally blocking birds from eating crops by conducting vinyl mulching after seeding and identifying the growing locations for beans to perform punching. Methods: Infrared (IR) sensors that could measure the temperature without contact were used to recognize the locations of soybean cotyledons below vinyl mulch. To expand the measurable range, 10 IR sensors were arranged in a linear array. A sliding mechanical device was used to reconstruct the two-dimensional spatial variance information of targets. Spatial interpolation was applied to the two-dimensional temperature distribution information measured in real time to improve the resolution of the bean coleoptile locations. The temperature distributions above the vinyl mulch for five species of soybeans over a period of six days from the appearance of the cotyledon stage were analyzed. Results: During the experimental period, cases where bean cotyledons did and did not come into contact with the bottom of the vinyl mulch were both observed, and depended on the degree of growth of the bean cotyledons. Although the locations of bean cotyledons could be estimated through temperature distribution analyses in cases where they came into contact with the bottom of the vinyl mulch, this estimation showed somewhat large errors according to the time that had passed after the cotyledon stage. The detection results were similar for similar types of crops. Thus, this method could be applied to crops with similar growth patterns. According to the results of 360 experiments that were conducted (five species of bean ${\times}$ six days ${\times}$ four speed levels ${\times}$ three repetitions), the location detection performance had an accuracy of 36.9%, and the range of location errors was 0-4.9 cm (RMSE = 3.1 cm). During a period of 3-5 days after the cotyledon stage, the location detection performance had an accuracy of 59% (RMSE = 3.9 cm). Conclusions: In the present study, to fundamentally solve the problem of damage to beans from birds in the early stage after seeding, a working method was proposed in which punching is carried out after seeding, thereby breaking away from the existing method in which seeding is carried out after punching. Methods for the accurate detection of soybean growing locations were studied to allow punching to promote the continuous growth of soybeans that had reached the cotyledon stage. Through experiments using multiple IR sensors and a sliding mechanical device, it was found that the locations of the crop could be partially identified 3-5 days after reaching the cotyledon stage regardless of the kind of pulse crop. It can be concluded that additional studies of robust detection methods considering environmental factors and factors for crop growth are necessary.

• Journal of Korea Water Resources Association
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• v.48 no.8
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• pp.613-623
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• 2015

To overcome the difficulties of discharge measurements during flood season, MWSCM(micowave water surface current meter) which measures river surface velocities without contacting water has been applied in field work since its development. The existing version of MWSCM is for floods so that its applicability is low due to the short periods of floods. Therefore the renovative redesign of MWSCM to increase the applicability was conducted so that it can be applied to the discharge measurements during normal flows as well as flood ones by extending the measurable range of velocity. A newly developed high-performance MWSCM for general use can measure the velocity range of 0.03-20.0 m/s from flood flows to normal flows, whereas MWSCM for floods can measure the velocity range of 0.5-10.0 m/s. The improvement of antenna isolation between transmitter and receiver to block the inflow of transmitted singals to receiver and the improvement of phase noise of oscillator are necessary for detecting low velocity with MWSCM technology. Separate type antenna of transmitting and receiving signals is developed for isolation enhancement and phase locked loop synthesizer as an oscillator is applied to high-performance MWSCM for general use. Microwave frequency of 24 GHz is applied to the new MWSCM rather than 10 GHz to make the new MWSCM small and light for convenient use of it at fields. Improvement requests on MWSCM for floods-stable velocity measurement, self test, low power consumtion, and waterproof and dampproof-from the users of it has been reflected on the development of the new version of MWSCM.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.7
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• pp.1009-1013
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• 2013

In this study, we developed a fiber-optic goniometer for the continuous measurement of knee joint angle which provides important medical information on Alzheimer's disease. The fiber-optic goniometer is composed of a light-emitting diode (LED), a plastic optical fiber (POF), and a voltage output photodiode (PD). As a sensing part of the fiber-optic goniometer, a unclad fiber with regular intervals of 1 mm was fabricated to improve efficiency of bending loss according to the angle variation of knee joint. The emitting light with a center wavelength of 470 nm from a LED is guided by a POF to the PD, the transmitted light is then attenuated by the bending loss inside the bent POF. The intensity variation of the light transmitted from the POF gives rise to a change in output voltage in the fiber-optic goniometer. Therefore, we measured the real-time output voltage of the proposed fiber-optic goniometer using the unclad fiber according to the knee joint angle. Through the repeated experiments, the fiber-optic goniometer shows that it has a reversibility and a wide measurable angle range.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.272-279
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• 2018

This study was conducted to compare the muscle strength, muscle power, and H/Q ratio according to energy system contribution in athletes participating in various sports. Subjects of the study were assigned into an Anaerobic Exercise Group (AEG, n=60; Short-Distance, Weight Lifting, Jumping, Throwing, Bowling, Golf) and an Endurance Exercise Group (EEG, n=60; Modern Pentathlon, Field Hockey, Handball, Cycle, Boxing, Rowing) groups. Isokinetic peak torque/body weight% and flexor/extensor ratio at 60, 180 deg/sec of knee extension and flexion were measured using an cybex 770. Data analysis was conducted using an independent t-test and one-way ANOVA. Based on the results of this study, there was higher extension, flexion strength and flexion power in the AEG than the EEG (p<0.05). We also confirmed higher muscle strength and muscle power in short distance and jumping athletes than other athletes participating in other events (p<0.05). However, there was no significant difference within the endurance exercise group. The HS ratio was within a stable range of 50% to 60% in all events. Collectively, the outcomes of this study indicate that routine physiological and performance testing can provide measurable benefits for elite athletes and their coaches.

• Journal of the Korean Chemical Society
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• v.32 no.1
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• pp.22-29
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• 1988

The reaction of methanol-water mixture to $CO_2$ and $H_2$ on alkaline earth metal-copper-zinc oxide has been studied in the temperature range of 150 ${\sim}\;300^{\circ}C$. Generally the addition of the alkaline earth metal to Cu/ZnO resulted in an enhancement of selectivity for $CO_2$ formation and a reduction of catalytic activity. Measurable activities were found from 150$^{\circ}C$, 200$^{\circ}C$, and 250$^{\circ}C$ on Mg/Cu/ZnO, Ca/Cu/ZnO, and Ba/Cu/ZnO respectively. However, the highest selectivity for $CO_2$ formation was observed in Ba/Cu/ZnO catalyst at 250$^{\circ}C$. The effect of alkaline earth metal or ZnO on the reactivity was investigated using temperature programmed desorption of $CO_2$ or temperature programmed reduction with $H_2$ over catalysts respectively. It was found that $CO_2$ interacts more strongly in the sequence of MgO < CaO < BaO and ZnO decereases the reduction temperature of CuO. From the results, it was suggested that ZnO activates $H_2$ in the redox process of Cu component and alkaline earth metals adsorbs $CO_2$ in the catalytic process.

• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.215-219
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• 2009

To conduct a risk assessment of $AFB_1$ intake, $AFM_1$, which is a metabolite of $AFB_1$ in the human and porcine urine, was determined by competitive direct ELISA (cdELISA). The detection limit of cdELISA using anti-$AFM_1$ antibody and $AFB_1$-HRP conjugate was 10 pg/mL. The recoveries of $AFM_1$ were 117-167% after the addition of $AFM_1$ in the human urine in a range of 3-100 pg/mL. 165 samples (95.5%) of those obtained from 172 persons evidenced measurable levels of urinary $AFM_1$. The detected $AFM_1$ ranges were 0-11.6 pg/mL and the average level of $AFM_1$ contamination was 2.74${\pm}$ 1.89 pg/mL. The estimated amount of $AFM_1$ excretion in the human urine was 3.97 ng/day and the estimated $AFB_1$ intake amount was 79.4 ng/day. The probable daily intake (PDI) of $AFB_1$ by the subjects was estimated to be 1.28 ng/kg bw/day, which was higher than the tolerable daily intake (TDI, 0.15 ng/kg bw/day). In the case of porcine urine, the $AFM_1$ ranged between 0.97-26.7 pg/mL and the average contaminated $AFM_1$ was 10.62${\pm}$4.39 pg/mL. The estimated amount of $AFM_1$ excretion in the porcine urine was 27.6 ng/day, and the estimated $AFB_1$ intake amount was 551 ng/day.

• Journal of the Society of Disaster Information
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• v.14 no.3
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• pp.288-295
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• 2018

Purpose: The paper aims to compare the effectiveness of the two types of transport demand management measures, namely pull measures and push measures. Method: Case studies of two metropolitan areas in the developing world assess the extent to which increases in fuel prices can contribute to reducing automobile use and increasing the public transport use and the potential of urban rail transit to cause mode shift from automobiles. Within the case studies, a stated response survey of current car users has been conducted for Cairo and an on-line survey of rail transit users in Algiers. Results: There was a major proportion of car drivers who intend to switch to public transport, depending on the range of fuel prices in Cairo and a considerable proportion of rail users who have switched from automobiles resulting in a measurable reduction in CO2 emissions in Algiers. Conclusion: Investments in urban rail can be highly effective where there are demands for better public transport, but this type of pull measures can be much more effective if combined with push measures which significantly raise driving costs.