• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2503-2506
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• 2002

본 논문에서는 청소로봇의 주행에 관해 연구되어지고 있는 이론적인 제어알고리즘이 갖는 주행오차저감방법에 관해 연구하였다. 청소로봇의 양 바퀴의 속도에 따라 그려지는 이상적인 회전반경과 실제 실험을 통해 그려지는 회전반경은 다르다. 이는 청소로봇이 주행 시 나타나는 오차가 원인이다. 많은 이론적인 제어알고리즘이 청소로봇의 주행에 잘 적용되기 위해 주행 시 나타나는 오차를 수정하거나 보상해야 한다. 본 연구에서는 이상적인 회전반경과 실험을 통해 얻은 회전반경의 비교를 통해 오차와 회전반경을 구하고 이를 주행에 적용하고자 한다.

• Proceedings of the KOR-KST Conference
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• 1999.10a
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• pp.315-320
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• 1999

교차로 좌회전 이동류에 대해 곡선반경의 확보여부는 용량 및 안전성측면에 많은 영향을 주게 된다. 죄회전 곡선반경의 결정은 설계기준차량의 회전궤적에 따라 결정되며 곡선반경의 모양은 원곡선의 형태를 유지하는 것이 바람직한 형태로 제시되고 있다. 교차로 설게시 곡선반경의 확보방안으로 정지선을 후퇴시키는 방안을 제시함으로서 좌회전 이동류에 대해 용량 및 안전성을 개선할 수 있도록 하였다.

• Journal of Energy Engineering
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• v.10 no.3
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• pp.214-222
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• 2001

The purpose of this research it to develop gas-air rotary heat exchanger using heat pipe and the performances were examined by way of the theoretical analysis and the experiment. Centrifugal force to return the working fluid in heat pipe elements with different radius was evaluated as a function of the revolution speed and inclination angle, and a rotary heat exchanger with 60 heat pipes in 3 rows was designed and manufactured. The inclination angle of a heat pipe relative to the revolving axis was designed to be 2$^{\circ}$and water was used as a working fluid. Experimental result showed the heat exchange rate was enhanced by 16% with compared to the calculated value.

• Journal of the Korean Society for Railway
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• v.17 no.5
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• pp.336-341
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• 2014

The articulated structures seen in train or tram applications are being applied in road transportation systems, for use in mass passenger transit. When articulated vehicles are driven on public roads, they no longer follow a guided track. Therefore, there are a lot of control elements that need to be considered, such as turning radius, swept path width, off-tracking, and swing-out. Some of the currently available articulated vehicles on roads are equipped with an independent drive system; a system that has one motor at each wheel. Through this drive system, each wheel can be independently controlled, making precise and quick dynamic stability control possible. In this paper, we propose a torque distribution algorithm that can reduce the overall turning radius of the articulated vehicle, which has been verified through dynamic simulation.

• Journal of Korean Society of Transportation
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• v.25 no.1 s.94
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• pp.73-79
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• 2007

This study deals with traffic accidents at the ramps of trumpet interchanges. The purpose of the study is to analyze the relations between tke turning direction of ramps (and combinations with other factors) and traffic accidents. In Pursuing this analysis, this study gives particular attention to the combination of turning direction and grade and the combination of turning direction and radius of curvature in the case of the trumpet interchange ramps. The null hypothesis tests show that the average accident number and average accident rate ate rejected at the 90% and 95% significance level respectively Also. the null hypothesis tests show that the combinations or turning direction and Evade as well as turning direction and radius are all rejected at the 95% significance level. In summary, right turn movements ate more dangerous than left turns on the trumpet interchange vamps. Also, ramps with a right turn and up grade or with a left turn and radius more than 200m have more traffic accident Potential than other types of ramps.

• Journal of Korean Society of Transportation
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• v.27 no.3
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• pp.39-47
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• 2009

Currently, the minimum breadth as a point available for U-turn setup is designated as "over 9m for one way" in the traffic safety facilities practical manuals, and vehicles allowed to make a U-turn are limited to passenger cars. However, as passenger cars have recently become larger and SUVs (Sports Utility Vehicles) are being popularized, they fail to make a U-turn in one attempt. This causes a traffic jam and a problem with traffic safety. This study proposed, compared, and tested the measured values of actual differences in the turning radius of U-turn by actual cars with estimated values by using PC-Crash, a car accident simulation program. Then, the study forecasted the turning radius of U-turns of Korean passenger cars by using PC-Crash, and proposed appropriate breadth for U-turn setup.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.11
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• pp.2723-2729
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• 1993

Moire principles are applied to the measurement of the spindle radial error motion. As opposed to conventional techniques, no master cylinder or ball is needed in the measurement so that the offset and out-of-roundness errors of the master can be inherently eliminated. Two periodic circular gratings are used, one is made on the spindle and the other is held stationary on the reference frame. When the two gratings are seen superimposed during spindle rotation, an interference fringe pattern is observed from which the information on the eccentricity between the two gratings can be extracted with high precision. The optical design and fringe analysis techniques of a prototype measurement system are described in detail with exemplary measurement results.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.143-144
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• 2011

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.477-482
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• 1986

This trial was carried out to set up a proper drum speed of thresher to minimize the mechanical damage from threshing and thereby to obtain rye seeds possessing higher qualities for seeds. Rye plants were harvested at from 40 to 60 days after heading (DAH) with 5 days intervals and spread out on the field for 0, I, 2, 3 days for drying, respectively. After drying the plants were subjected to threshing at seven steps of drum speed from 400 to 1000 rotation per minute (RPM) of a thresher, drum diam. 18.6cm, teeth length 6cm. At 500 to 600 RPM and from the plants harvested at 55DAH with drying for one or two days, the seeds possessed low grain damage, high germinability over 90%, and field emergence rate over 80%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.83-89
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• 2021

To improve the performance of self-driving cars, the introduction of V2X, a communication technology that connects vehicles, infrastructure, and vehicles, is essential. Even if traffic information of the other vehicle is known, the structure of the intersection and a distance calculation algorithm are required for accurate calculations at roundabouts. This paper proposes a design algorithm for a rotating intersection and implemented in Matlab that complies with the national design rules and enables accurate calculations. Assuming the roundabout and the entrance/exit path to be a circle, a method for measuring the distance between vehicles at an arbitrary point was proposed using the horizontal shift of the entrance circle to the main circle. The algorithm could be used in fully autonomous vehicles by designing a roundabout suitable for the terrain by arbitrarily varying the angle between branches and the radius of curvature of the entrance and exit roads, and transmitting a warning signal when a collision between two driving vehicles is expected.