• Journal of Power Electronics
• /
• 제16권5호
• /
• pp.1661-1668
• /
• 2016

A fixed off-time controlled high power factor ac-dc LED driver is proposed in this paper, which employs a novel zero-crossing-compensation (ZCC) circuit based on a fixed off-time controlled scheme. Due to the parasitic parameters of the system, the practical waveforms have a dead region. By detecting the zero-crossing boundary, the proposed ZCC circuit compensates the control signal VCOMP within the dead region, and is invalid above this region. With further optimization of the parameters KR and Kτ of the ZCC circuit, the dead zone can be eliminated and lower THD is achieved. Finally, the chip is implemented in HHNEC 0.5μm 5V/40V HVCMOS process, and a prototype circuit, delivering 7~12W of power to several 3-W LED loads, is tested under AC input voltage ranging from 85V to 265V. The test results indicate that the average total harmonic distortion (THD) of the entire system is approximately 10%, with a minimum of 5.5%, and that the power factor is above 0.955, with a maximum of 0.999.

• 제어로봇시스템학회논문지
• /
• 제22권11호
• /
• pp.967-976
• /
• 2016

This paper presents a 3D carrier-smoothed GNSS/DR (Global Navigation Satellite System/Dead Reckoning) integrated system for precise ground-vehicle trajectory estimation. For precise DR navigation on sloping roads, the AHRS (Attitude Heading Reference System) methodology is employed. By combining the integrated carrier phase of GNSS and DR sensor measurements, a vehicle trajectory with an accuracy of less than 20cm is obtained even when cycle slip or change of visibility occur. In order to supplement the weak GNSS environment with DR successfully, the DR sensor is precisely compensated for using GNSS Doppler measurements when GNSS visibility is good. By integrating a multi-GNSS receiver with low-cost IMU, a precise 3D navigation system for land vehicles is proposed in this paper. For real-time implementation, a decoupled Kalman filter is employed in the integrated system. Through field experiments, the performance of the proposed system is verified in various road environments, including sloping roads, good-visibility areas, high multi-path areas, and under-ground parking areas.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2023년도 봄 학술논문 발표대회
• /
• pp.367-368
• /
• 2023

Kiscon, Seumteo, KONEPS and CSI are representative construction-related DBs. All four DBs are operated by the public. However, the characteristics of data are different depending on the purpose. Therefore, it is difficult to utilize integrated data and it is only used sparingly. Creating and sharing a unique key that can identify a construction site will enable integrated accumulation and management of construction-related data for various purposes. At this point, it is most efficient to assign a unique key based on KISCON. KISCOn data conforms to the construction site definition and covers most of the public, private, architectural and civil works. In addition, there is an advantage in that DB construction is performed in the construction situation, which is a relatively preceding process. In the future, it is necessary to create a practical construction site integrated DB through the production of an integrated key table containing linkage information of unique keys for site management, performance indicators, and statistics production.

• Journal of Positioning, Navigation, and Timing
• /
• 제1권1호
• /
• pp.51-57
• /
• 2012

In this paper, design of an error model is presented in which the bias characteristic of the MEMS IMU is taken into consideration for performance enhancement of the MEMS IMU-based GPS/INS integrated navigation system. The drift bias of the MEMS IMU is modeled as a 1st-order Gauss-Markov (GM) process, and the autocorrelation function is obtained from the collected IMU data, and the correlation time is estimated from this. Prior to obtaining the autocorrelation function, the noise of IMU data is eliminated based on wavelet. As a result of simulation, it is represented that the parameters of error model can be estimated correctly only when a proper denoising is performed according to dynamic behavior of drift bias, and that the integrated navigation system based on error model, in which the drift bias is considered, provides more correct navigation performance compared to the integrated navigation system based on error model in which the drift bias is not considered.

• Journal of Power Electronics
• /
• 제18권2호
• /
• pp.640-650
• /
• 2018

A TRIAC dimmable LED driver with a wide tuning range and a two-stage uniform dimming scheme is proposed in this paper. To solve the restricted dimming range problem caused by the limited conduction ratio of TRIAC dimmers, a conduction ratio compensation technique is introduced, which can increase the output current up to the rated output current when the TRIAC dimmer turns to the maximum conduction ratio. For further optimization, a two-stage uniform dimming diagram with a rapid dimming curve and a slow dimming curve is designed to make the LED driver regulated visually uniform in the whole adjustable range of the TRIAC dimmer. The proposed control chip is fabricated in a TSMC $0.35{\mu}m$ 5V/650V CMOS/LDMOS process, and verified on a 21V/500mA circuit prototype. The test results show that, in the 90V/60Hz~132V/60Hz ac input range, the voltage linear regulation is 2.6%, the power factor is 99.5% and the efficiency is 83%. Moreover, in the dimming mode, the dimming rate is less than 1% when the maximum dimming current is 516mA and the minimum dimming current is only about 5mA.

• Journal of Astronomy and Space Sciences
• /
• 제28권2호
• /
• pp.123-132
• /
• 2011

It is generally believed that the occurrence of a magnetic storm depends upon the solar wind conditions, particularly the southward interplanetary magnetic field (IMF) component. To understand the relationship between solar wind parameters and magnetic storms, variations in magnetic field polarity and solar wind parameters during magnetic storms are examined. A total of 156 storms during the period of 1997~2003 are used. According to the interplanetary driver, magnetic storms are divided into three types, which are coronal mass ejection (CME)-driven storms, co-rotating interaction region (CIR)-driven storms, and complicated type storms. Complicated types were not included in this study. For this purpose, the manner in which the direction change of IMF $B_y$ and $B_z$ components (in geocentric solar magnetospheric coordinate system coordinate) during the main phase is related with the development of the storm is examined. The time-integrated solar wind parameters are compared with the time-integrated disturbance storm time (Dst) index during the main phase of each magnetic storm. The time lag with the storm size is also investigated. Some results are worth noting: CME-driven storms, under steady conditions of $B_z$ < 0, represent more than half of the storms in number. That is, it is found that the average number of storms for negative sign of IMF $B_z$ (T1~T4) is high, at 56.4%, 53.0%, and 63.7% in each storm category, respectively. However, for the CIR-driven storms, the percentage of moderate storms is only 29.2%, while the number of intense storms is more than half (60.0%) under the $B_z$ < 0 condition. It is found that the correlation is highest between the time-integrated IMF $B_z$ and the time-integrated Dst index for the CME-driven storms. On the other hand, for the CIR-driven storms, a high correlation is found, with the correlation coefficient being 0.93, between time-integrated Dst index and time-integrated solar wind speed, while a low correlation, 0.51, is found between timeintegrated $B_z$ and time-integrated Dst index. The relationship between storm size and time lag in terms of hours from $B_z$ minimum to Dst minimum values is investigated. For the CME-driven storms, time lag of 26% of moderate storms is one hour, whereas time lag of 33% of moderate storms is two hours for the CIR-driven storms. The average values of solar wind parameters for the CME and CIR-driven storms are also examined. The average values of ${\mid}Dst_{min}{\mid}$ and ${\mid}B_{zmin}{\mid}$ for the CME-driven storms are higher than those of CIR-driven storms, while the average value of temperature is lower.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
• /
• pp.409-409
• /
• 2000

In this paper, the implementation of a tightly coupled real-time GPS/INS integrated system is discussed. The hardware is developed for any GPS receiver and any IMU. The navigation software is modularized by tasks, so that can be easily modified when the integrated system is restructured. A van test was performed to show the feasibility of the proposed system.

• Journal of Animal Science and Technology
• /
• 제61권6호
• /
• pp.379-387
• /
• 2019

The purpose of this study is to identify the effects of a group integrated intervention program that simultaneously conducts cognitive activities, physical activities, emotional activities and social interactions by integrating animal-assisted therapy (AAT) and integrated elderly play therapy based on the cognitive functions and depression of the elderly who live alone. This study follows a pre-test post-test design with a nonequivalent control group, to verify the effectiveness of a group integrated intervention. It applies a group integrated intervention program to 20 elderly people who live alone, aged 65 and above (10 in the experimental group, 10 in the control group), once a week for 90 minutes across eight weeks. The study went through MMSE-K, TMT-A and GDSSF-A to assess cognitive functions and the level of depression. The group integrated intervention increased the cognitive functions of the experimental group and decreased levels of depression. Therefore, this study verified that a group integrated intervention program of AAT and integrated play therapy of the elderly, is an effective for increasing cognitive functions and decreasing depression levels of the elderly who live alone. Based on these findings, the study suggests that there is a need to continuously expand group integrated intervention programs and provide relevant political support.

• 교육녹색환경연구
• /
• 제3권2호
• /
• pp.39-49
• /
• 2003

This study purpose is extract on the architectural principles and architectural planning direction for Integrated Secondary School. The integrated secondary school has an expectation of the total education environment in which has some problem as regional, teaching, treatment, establishment equipment part because of the based relative establishments are abolished. The expectations are the education effective rising, the reduce of the responsibility of the teacher, a smooth teacher placing and saving the educating estimate. As the new education course propulsion is raising the school and students discretion and expanding the way of educating, being close to the course of studies, the integrated operation is earnestly needed and such as these versatile background the small school will keep on getting integrated. Investigate about the senses of the manager and teachers, so after these reserch I've concluded these things below about the integrated secondary school.

• 무역학회지
• /
• 제47권6호
• /
• pp.377-393
• /
• 2022

This study aims to identify the effect of growth of the land transportation industry on economic growth and to provide implications for Korea's metropolitan region policy. The effect of each metropolitan region on the integrated region where each metropolitan region is integrated is as follows. First, The integrated region where each metropolitan region was integrated with the Southeast region and the Daegyeong region had the greatest economic growth effect due to the growth of the land transportation industry in terms of value added, but the effect of the integrated region with the Chungcheong region was the least. In the case of capital such as roads, the integrated metropolitan regions with the Chungcheong region showed the greatest economic effect. However, the impact of the integrated regions with Jeolla region and the Seoul metropolitan region is insignificant. These results suggest that the synergy effect of metropolitan regional integration by spillover effect such as networks should be considered in the land transportation industry policy.