• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.1615_1616
• /
• 2009

LED 조명기구의 광학적, 기구적 설계의 최적화 방안이 여러 가지로 논의 되고 있는 가운데, 본 연구에서는 LED 조명기구 중에서도 점차 활용에 대한 시도가 증가하고 있는 LED 가로등의 적절한 배광을 달성하기 위한 광학 설계를 하였다. 그리고 Lens와 Reflector의 결합이 아닌 Reflector만을 이용한 배광 제어 설계 방법을 제시 하였다. LED 가로등 모듈의 설계는 Photopia를 사용하였고, 도로 적용 시뮬레이션은 Relux를 이용하여 설계결과에 대한 성능을 검증하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2022.10a
• /
• pp.418-419
• /
• 2022

In this paper, the design of the fusion sensor mechanism was divided into primary and secondary design, and the device design and case design were divided to facilitate the safety of the sensor, sensor coupling, and connection with power.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.11 no.3
• /
• pp.274-283
• /
• 2006

The Permanent Magnet Synchronous Motor(PMSM) drive systems with ball-screw, gear and timing-belt are widely used in industrial applications such as NC machine, machine tools, robots and factory automation. These systems have torsional vibration in torque transmission from servo motor to mechanical load due to the mechanical couplings. This vibration makes it difficult to achieve quick responses of speed and may result in damage to the mechanical plant. This paper presents adaptive notch filter with auto searching function of vibration frequency to reject the mechanical vibration of linear feeder system with PMSM. The proposed adaptive notch filter can suppress the torque command signal of PMSM in the resonant bandwidth for reject the mechanical torsional vibration. However, the resonant frequency can vary with conditions of mechanical load system and coupling devices, adaptive notch filter can auto search the vibration frequency and suppress the vibration signal bandwidth. Computer simulation and experimental results shows the verification of the proposed adaptive notch filter in linear feeder system with PMSM.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2003.03a
• /
• pp.196-196
• /
• 2003

• Proceedings of the Korean Ceranic Society Conference
• /
• 2002.10a
• /
• pp.155.2-155
• /
• 2002

• Journal of the Korean Institute of Intelligent Systems
• /
• v.25 no.3
• /
• pp.236-241
• /
• 2015

This paper presents a study on transformable multiple quadruped robots by docking between robots and waist joints. This robot is able to go on a variety of angles because of mecanum wheels. It is also a hybrid design which allows robot use legs to overcome obstacles on complex terrains and wheels to move on flat ground. The robot is applied kinematics of mecanum wheels and walking, and its walking is based on specific patterns. Docking module is located in front and backside of robot, docking algorithm is suggested and fulfilled for docking between 2 robots. A waist joint is at the center of robot body for transformation and after docking and transformation, robot can activate new functions that carry something.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.47 no.1
• /
• pp.49-58
• /
• 2019

The Scientific balloon is a flight system that could recover an entire platform at the end of the mission. The recovery takes place mainly in low-density populated areas, taking into account for the possible damage to the human life and public safety. In Republic of Korea, on the other hand, marine recovery should be considered due to the dense mountainous terrain and restrictions of the peninsula. In this operating environment, the envelope must be recovered because of severe marine pollution that may occur after the splashdown. Therefore, in this study, the separation device that consists of a location tracker and the waterproof system were developed. The device includes data transmission/reception, separation, and waterproof systems which are manufactured considering the environmental condition of the Korea. The performance of the device and the trajectory of the envelope were verified by conducting a separation test of a 20km platform at a target altitude and the recovery of the zero-pressure balloon.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.20 no.3
• /
• pp.311-317
• /
• 2010

In the paper, we propose an improved mobility method of modular robots by physical docking in the uneven environments. The modular robot system consists of autonomous docking device, 3 DOF robotic arm, motion controller, and main controller. Real-time location and direction of the robot are estimated using inner GPS and they are used to control direction and path of each robot for physical docking between modular robots. We design a navigation algorithm of modular robot using physical docking and cooperative navigation in the environment with broken road and low stair. The proposed method is verified by navigation experiments of three developed modular robots in the uneven environments.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2007.06a
• /
• pp.219-222
• /
• 2007

본고에서는 최근에 IMO에서 시행될 VDR(Voyage Data Recorder)에 대해 분석하고 특히 통신설비와 결합된 부양형 S-VDR(Simplified -Voyage Data Recoder)에 대한 통신 기술적 측면에 대해서 기술하였다. 이 장비에 결합된 통신 기술은 기존 EPIRB(Emergency Position Indicating Radio Beacon) 기술을 S-VDR과 결합한 것으로 통신적인 측면에서 기술적인 변화는 없다. VDR의 경우에도 기능을 단순화하여 경제적인 항행장비인 S-VDR로 변화되었으나 기술적인 측면의 변화는 없다. 부양형 S-VDR은 통신 기능을 포함하고 있으므로 통신설비이며 기존익 조난 구조를 위한 EPIRB를 대신할 수 없다. 그러므로 본고에서는 부양형 S-VDR에 대한 국제 표준화기구(IMO, IEC, ITU, COSPAS-SARSAT 등)의 관련 자료를 분석하고 사용 범위 및 용도 등을 명확히 정리했으며 이 결과가 해상통신 관련 규정에 반영되도록 제안하였다.

• Restorative Dentistry and Endodontics
• /
• v.35 no.1
• /
• pp.13-19
• /
• 2010

The purpose of this study was to compare the microshear bond strength of a self-etching primer adhesive to dentin prepared with different diamond points, carbide burs and SiC papers, and also to determine which SiC paper yield similar strength to that of dentinal surface prepared with points or burs. Fifty-six human molar were sectioned to expose the occlusal dentinal surfaces of crowns and slabs of 1.2 mm thick were made. Dentinal surfaces were removed with three diamond points, two carbide burs, and three SiC papers. They were divided into one of eight equal groups (n = 7); Group 1: standard diamond point(TF-12), Group 2: fine diamond point (TF-12F), Group 3: extrafine diamond point (TF-12EF), Group 4: plain-cut carbide bur (no. 245), Group 5: cross-cut carbide bur (no. 557), Group 6 : P 120-grade SiC paper, Group 7: P 220-grade SiC paper, Group 8: P 800-grade SiC paper. Clearfil SE Bond was applied on dentinal surface and Clearfil AP-X was placed on dentinal surface using Tygon tubes. After the bonded specimens were subjected to uSBS testing, the mean uSBS (n = 20 for each group) was statistically compared using one-way ANOV A and Tukey HSD test. In conclusion, the use of extrafine diamond point is recommended for improved bonding of Clearfil SE Bond to dentin. Also the use of P 220-grade SiC paper in vitro will be yield the results closer to dentinal surface prepared with fine diamond point or carbide burs in vivo.