• 한국정보전자통신기술학회논문지
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• 제14권5호
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• pp.385-393
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• 2021

본 논문에서는 차량 멀티코어 프로세서를 통한 ESC(Electronic Stability Control) 시스템을 위한 멀티코어 기반 제어기를 제시한다. 차량용 멀티코어 프로세서와 ESC 시스템의 아키텍처를 고려할 때 ESC 소프트웨어의 전체 수행 시간은 멀티코어에 최적화되어 있다. 일반적으로 차량용 멀티코어 시스템에서는 코어 간 동기화, 멀티코어에 대한 테스크 할당, 코어 종속 변수에 대한 메모리 할당을 고려해야 한다. 본 논문에 사용된 ESC 시스템은 초기화, SlipRatio 계산, YawRate 계산, ABS, 통신으로 구성된다. 제안된 설계 방법을 기반으로 싱글코어 프로세서는 멀티코어 프로세서로 확장된다. ESC 시스템은 기능 모듈 할당, 세마포어, 인터럽트, 코어 별 변수 할당과 같은 멀티코어 최적화 방법을 사용하여 멀티코어 제어기로 재설계된다. 실험 결과로 멀티코어 프로세서의 수행 시간이 싱글코어 프로세서에 비해 59.7% 단축되었다.

• 대한교통학회지
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• 제35권4호
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• pp.307-320
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• 2017

본 연구는 메타분석(Meta-Analysis) 기법을 적용하여 ESC(Electronic Stability Control) 시스템의 교통안전 측면의 효과를 평가하였다. 교통안전성의 평가지표로 사고율, 사망사고율, 통제상실 사고율을 설정하였으며 ESC를 주요 키워드로 선정하여 기존 문헌을 수집하였다. 수집된 연구결과를 승산비의 효과크기(Effect-size)로 정리하였고, 개별 연구들 간의 이질성을 고려하여 랜덤효과모형을 적용해 통합 승산비 효과크기를 도출하였다. 분석결과, 사고율의 승산비 효과크기는 0.90으로 차량에 ESC 적용 시 사고율이 10% 감소하는 것으로 나타났다. 또한 사망사고율의 승산비 효과크기는 0.64로 차량에 ESC 시스템 적용 시 사망사고율이 36% 감소하는 것으로 분석되었다. 통제상실 사고율의 승산비 효과크기는 0.73으로 도출되어 ESC 시스템 적용 시통제상실 사고율이 27% 감소하는 것으로 분석되었다. 본 연구의 결과는 상용차 ESC 장착 의무화를 위한 제도 정비 및 관련 기술 개발 전략 수립 시 유용하게 활용될 수 있을 것으로 판단된다.

• 전기학회논문지
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• 제59권12호
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• pp.2306-2313
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• 2010

This paper describes a model based fault detection algorithm for an Advanced ESC System which consists of Hydraulic Control Unit (HCU) with built-in wheel pressure sensors. Advanced ESC System can be used for various value-added functions such as Stop & Go Function and Regenerative Brake Function. Therefore, HCU must have a reliable fault detection. Due to the huge amount of sensor signals, existing specific sensor based fault detection of HCU cannot guarantee the safety of vehicle. However, proposed algorithm dose not require the sensors. When model based fault detection algorithm detects severe failures of the HCU, it warns the driver in advance to prevent accidents due to the failures. For this purpose, a mathematical model is developed and validated in comparison to actual data. Simulation results and data acquired from an actual system are compared with each other to obtain the information needed for the fault detection process.

• 한국자동차공학회논문집
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• 제21권5호
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• pp.87-96
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• 2013

This paper shows how the performance of an ESC(Electronic Stability Control) system can be affected by the selection of in-vehicle network protocols such as CAN or FlexRay. The vehicle control performance under ESC operation is analyzed by EILS(ECU-In-the-Loop Simulation). The experimental set-up for the EILS of the ESC system consists of two 32-bit microcontroller boards communicated with CAN or FlexRay protocols. A 7-DOF vehicle model and an ESC algorithm with 2-DOF reference vehicle model are implemented on each microcontroller respectively. It is shown by experimental results that the ESC system using the FlexRay protocol can achieve better performance than that using the CAN protocol for a fast and accurate lane changing.

• 조명전기설비학회논문지
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• 제21권5호
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• pp.106-111
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• 2007

반도체 공정에서 각 단계별 과정을 거친 후 dechucking시 wafer가 ESC(Electrostatic Chuck)로부터 방전되지 못하고, 잔류되어 있는 극성을 띤 전하(Electric charge)들에 의해 wafer와 ESC사이에 인력이 발생하여 wafer의 sliding, popping 및 wafer broken 등의 문제가 발생한다. 본 논문에서는 wafer와 ESC의 구성을 capacitor를 이용하여 modeling하고, PSpice를 사용하여 chucking system에 의한 wafer의 대전 현상을 모의하고 그 결과를 바탕으로 잔류전하를 방전시키기 위한 여러 가지 방법을 검토하여 최적의 잔류전하 제거 기법을 제시한다. 즉 별도의 전압원을 사용하여 (+)와 (-)를 교번하는 구형파를 인가함과 아울러 일정시간 동안 Plasma내에서 스위칭시킴으로써 ESC나 wafer에 charge되어 있는 극성을 띤 전하들을 중화(Neutralize) 시키도록 하였다. 그리고 이를 실제 하드웨어로 구현하여 실 공정에 적용한 결과를 제시한다.

• 자동차안전학회지
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• 제7권2호
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• pp.32-38
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• 2015

A sine with dwell test is well known as a test scenario for evaluation of performance of electronic stability control(ESC) on passenger vehicles and heavy commercial vehicles. However, when it comes to ESC for medium commercial vehicles, the test scenario has not been established yet. In this paper, the sine with dwell test was modified considering characteristics of medium commercial vehicles. The three main modifications of the original test scenario are the steering angle level, steering frequency, and loading condition of the vehicle. These modifications are derived from simulation study for different medium commercial vehicles. From simulation study, it was shown that the ESC system for medium commercial vehicle is objectively evaluated by the proposed test scenario. A clear improvement on vehicle stability was seen in the results when ESC system was used.

• 반도체디스플레이기술학회지
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• 제1권1호
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• pp.9-13
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• 2002

A polyimide-type electrostatic chuck (ESC) was fabricated for the application of holding 8-inch silicon wafers in the oxide etching equipment. For the fabrication of the unipolar ESC, core technologies such as coating of polyimide films and anodizing treatment of aluminum surface were developed. The polyimide films were prepared on top of thin coated copper substrates for the good electrical contacts, and the helium gas cooling technique was used for the temperature uniformity of the silicon wafers. The ESC was essentially working with an unipolar operation, which was easier to fabricate and operate compared to a bipolar operation. The chucking force of the ESC has been measured to be about 580 gf when the applied voltage was 1.5 kV, which was considered to be enough force to hold wafers during the dry etching processing. The employment of the ESC in etcher system could make 8% enhancement of the wafer processing yield.

• 한국항행학회논문지
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• 제27권2호
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• pp.214-220
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• 2023

모터와 ESC (Electronic Speed Control)는 높은 효율을 유지할 수 있는 회전 속도 및 토크의 범위가 존재하기 때문에, 효율적인 시스템 설계를 위해서는 이 범위를 파악하는 것이 중요하다. 본 논문에서는 먼저 측정 장비 대한 정확성을 프로펠러 측정 데이터와 비교 분석하여 검증하였다. 다음으로, 넓은 회전 속도 범위에서의 정적 측정을 통해 각 프로펠러에 대한 통합 효율을 측정하고, 이를 다수의 프로펠러에서 반복하여 얻은 데이터를 이용하여 효율 등치선도를 도출하였다. 측정된 모터-ESC 통합 효율은 단순한 모터 모델로 도출한 모터 자체의 효율과 비교할 때 상당한 차이가 있음을 확인하였고, 또한 동일한 모터라도 ESC에 따라 달라지는 효율의 차이를 분석하였다. 본 연구를 통해 도출한 모터-ESC 통합 효율 등치선도는 추진 효율이 중요한 항공기의 전기 추진 시스템을 설계하고 최적화하는 데에 유용하게 사용될 것으로 예상된다.

• Advances in Automotive Engineering
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• 제1권1호
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• pp.123-141
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• 2018

Hardware-in-the-loop (HiL) simulation is a very powerful tool to design, test and verify automotive control systems. However, well-validated and high degree of freedom vehicle models have to be utilized in these simulations in order to obtain realistic results. In this paper, a vehicle dynamics model developed in the Carsim Real Time program environment and its validation has been performed using experimental results. The developed Carsim real time model has been employed in the Tofas R&D hardware-in-the-loop simulator. Experimental and hardware-in-the-loop simulation results have been compared for the standard FMVSS No. 126 test and the results have been found to be in good agreement with each other. Two electronic stability control (ESC) algorithms, named the Basic ESC and the Integrated ESC, taken from the earlier work of the authors have been tested and evaluated in the hardware-in-the-loop simulator. Different evaluation methods have been formulated and used to compare these ESC algorithms. As a result, the Integrated ESC system has been shown superior performance as compared to the Basic ESC algorithm.

• Reproductive and Developmental Biology
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• 제34권3호
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• pp.143-151
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• 2010

Pluripotency of human embryonic stem cell (hESC) is one of the most valuable ability of hESCs for applying cell therapy field, but also showing side effect, for example teratoma formation. When transplant multipotent stem cell, such as mesnchymal stem cell (MSC) which retains similar differentiation ability, they do not form teratoma in vivo, but there exist limitation of cellular source supply. Accordingly, differentiation of hESC into MSC will be promising cellular source with strong points of both hESC and MSC line. In this study, we described the derivation of MSC like cell population from feeder free cultured hESC (hESC-MSC) using direct differentiation system. Cells population, hESC-MSC and bone marrow derived MSC (BM-MSC) retained similar characteristics in vitro, such as morphology, MSC specific marker expression and differentiation capacity. At the point of differentiation of both cell populations, differentiation rate was slower in hESC-MSC than BM-MSC. As these reason, to verify differentially expressed molecular condition of both cell population which bring out different differentiation rate, we compare the molecular condition of hESC-MSC and BM-MSC using 2-D proteomic analysis tool. In the proteomic analysis, we identified 49 differentially expressed proteins in hESC-MSC and BM-MSC, and they involved in different biological process such as positive regulation of molecular function, biological process, cellular metabolic process, nitrogen compound metabolic process, macromolecule metabolic process, metabolic process, molecular function, and positive regulation of molecular function and regulation of ubiquitin protein ligase activity during mitotic cell cycle, cellular response to stress, and RNA localization. As the related function of differentially expressed proteins, we sought to these proteins were key regulators which contribute to their differentiation rate, developmental process and cell proliferation. Our results suggest that the expressions of these proteins between the hESC-MSC and BM-MSC, could give to us further evidence for hESC differentiation into the mesenchymal stem cell is associated with a differentiation factor. As the initial step to understand fundamental difference of hESC-MSC and BM-MSC, we sought to investigate different protein expression profile. And the grafting of hESC differentiation into MSC and their comparative proteomic analysis will be positively contribute to cell therapy without cellular source limitation, also with exact background of their molecular condition.