• 한국생산제조학회지
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• 제24권2호
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• pp.203-210
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• 2015

This paper investigates the failure of a car with a 2.5-liter CRDi engine of the Hyundai Company. The failure is caused by intermittent poor acceleration while driving. To analyze the cause, we investigated the air intake volume, the fuel injection, and the air-fuel ratio, which were determined to be normal. The brake switch signal error was discovered while analyzing the function that limits the output of the engine. While investigating the cause, we discovered the corrosion of the pins on the connector of the brake switch. We determined that it was generated by soapy water flowing in the solar film. Therefore, the cause of the failure was the brake switch signal errors. Additionally, we determined that ECM was the normal fail-safe mode that implemented the override device for safety during normal acceleration. Based on these results, further solar film experiments must be conducted to fully elucidate the causes.

• Nuclear Engineering and Technology
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• 제47권2호
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• pp.165-175
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• 2015

The application of neutron noise analysis (NNA) to the ex-core neutron detector signal for monitoring the vibration characteristics of a reactor core support barrel (CSB) was investigated. Ex-core flux data were generated by using a nonanalog Monte Carlo neutron transport method in a simulated CSB model where the implicit capture and Russian roulette technique were utilized. First and third order beam and shell modes of CSB vibration were modeled based on parallel processing simulation. A NNA module was developed to analyze the ex-core flux data based on its time variation, normalized power spectral density, normalized cross-power spectral density, coherence, and phase differences. The data were then analyzed with a fuzzy logic module to determine the vibration characteristics. The ex-core neutron signal fluctuation was directly proportional to the CSB's vibration observed at 8Hz and15Hzin the beam mode vibration, and at 8Hz in the shell mode vibration. The coherence result between flux pairs was unity at the vibration peak frequencies. A distinct pattern of phase differences was observed for each of the vibration models. The developed fuzzy logic module demonstrated successful recognition of the vibration frequencies, modes, orders, directions, and phase differences within 0.4 ms for the beam and shell mode vibrations.

• 한국자동차공학회논문집
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• 제16권3호
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• pp.23-29
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• 2008

It is necessary to develope the active safety system in terms of driver's safety and convenience. In this paper, we were developed the non-contact type of safety window system operated by the initial value of feedback control such as the output signal of photo sensor. It was designed based on the control algorithm with an improved load sensitivity. Therefore, compared with the existing system, it is possible to prevent the occurrence of a mull-function. Also, it has a convenient functions of the window such as an auto up/down and closing, and has a response times better. It can be installed the various types of common vehicles that have the different movement distance and speed of window. In conclusion, the developed system may be adapted the vehicle commercially.

• Journal of Astronomy and Space Sciences
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• 제25권2호
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• pp.227-238
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• 2008

위성항법 지상국 기술은 위성으로부터 위성항법신호를 받아 위성항법신호를 감시하고 분석하며 위성에 보정정보를 업로드하는 기술로써 위성항법 인프라 구축에 매우 중요한 기술이며 여러 응용분야에 적용할 수 있는 핵심 기술이다. 이 중 한국전자통신연구원에서 개발하고 있는 감시제어시스템은 GPS 및 갈릴레오 항법 위성으로부터 신호 감시 데이터를 수집하여 위성항법 제어센터로 제공하는 기능을 수행하는 소프트웨어 시스템이다. 이 논문에서는 위성항법 지상국의 구성과 감시제어시스템의 목적 및 형상을 소개한 다음, 감시제어시스템의 적용 알고리즘을 소개하고 감시제어시스템의 예비설계를 기술하였다. 감시제어시스템은 데이터 수집, 데이터 포맷팅 및 저장, 데이터 오차 보정, 항법해 결정, 독립 품질 감시, 시스템 운용 및 유지 등의 모듈로 구성되어 있다. 감시제어시스템의 예비설계는 유스케이스 모델, 도메인 설계, 소프트웨어 구조설계, 사용자 인터페이스 구조 설계 과정을 통하여 이루어진다. 각 단계별 설계과정은 UML(Unified Modeling Language) 표준 방식에 따라 이루어졌다. 이 연구에서 설계된 감시제어시스템은 지상국의 운용 능력을 향상시킬 뿐만 아니라 상세설계의 기초자료로 이용될 것이다.

• 융복합기술연구소 논문집
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• 제1권2호
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• pp.1-5
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• 2011

It is known that as many as 15-20 in 10,000 children are diagnosed with autistic spectrum disorder. A framework of the treatment system for children with autism using affective computing technologies was proposed by Chung and Yoon. In this paper, a prototype for the framework is proposed. It consists of emotion stimulating module, multi-modal bio-signal sensing module, treatment module using virtual reality, and emotion recognition module. Primitive experiments on emotion recognition show the usefulness of the proposed system.

• 산업공학
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• 제21권1호
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• pp.85-95
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• 2008

Reliability prediction serves many purposes during the life of a system, so several methods have been developed to predict the parts and systems reliability. MIL-HDBK-217F, among the those methods, has been widely used as a requisite tool for the reliability prediction which is applied to nuclear power plants and their safety regulations. This paper presents the reliability prediction for the DSP(Digital Signal Processor) module composed of three assemblies. One of the assemblies has a monitoring and self test function which is used to enhance the module reliability. The reliability of each assembly is predicted by MIL-HDBK-217F. Based on these predicted values, Markov modelling is finally used to predict the module reliability. Relax 7.7 software of Relax software corporation is used because it has many part libraries and easily handles Markov processes modelling.

• Journal of Advanced Marine Engineering and Technology
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• 제29권5호
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• pp.587-592
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• 2005

The ESS(Energy Saving System) is designed to have functions of controlling. monitoring for cooling system. etc. ESS consists of the I/O module, CPU module and Display module I/O module detects various ESS data on local area and treats signals via I/O interface system. The interface system receives various status data and outputs control signals. ESS is tested with dummy signal to verify proposed functions and is shown good results. For future study ESS will be tested under real condition in the ship.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1993년도 추계학술대회 논문집
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• pp.237-242
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• 1993

In the cluster tool, it is necessary to precisely control the vacuum pressure for the wafer transportation between transport module and cassette or process with the range of 10 $^{-4}$ to 5*10 $^{-5}$ torr. So we have designed the pressure control system for the transport module of the cluster tool and have evaluated its performance. Digital PID is utilized with the weighted sum of both three previous errors and one current error. The feedback signal is put into the nitrgen mass flow controller using the transport module controller. This pressure control system can prevent the transport module from the particle generation and backstreaming of hazardous process gases of the process chamber.

• 전기학회논문지P
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• 제64권4호
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• pp.291-296
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• 2015

Transmission line is exposed to a large area, and then faults are likely to occur than the other component of power system. When a fault occurs on a transmission line, fault locator helps fast recovery of power supply on power system. This paper deals with the design of a digital fault locator for improvement accuracy of the fault distance estimation and a fault occurrence position for transmission line. The algorithm of a fault locator uses a DC offset removal filter and DFT filter. The algorithm utilizes a fault data of GPS time synchronized. The computed fault information is transmitted to the other side substation through communication. The digital fault locator includes MPU module, ADPU module, SIU module, and a power module. The MMI firmware and software of the fault locator was implemented.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.885-890
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• 2007

Fast Fourier Transformation(FFT) is one of the most useful way to analyze response signal for the purpose of grasping the dynamic characteristics of system. Vibration test using impact hammer is typical and simple experimental method widely used for catching hold of dynamic peculiar characters and modal behaviors of system. In this thesis, impact testing module for NI-PXI equipment is developed. The analyzing and visualizing module are developed with LabVIEW tool. A user can see quickly and easily modal shape of system after analyzing acquired data. This developed module will be expected to build up more convenient and serviceable measurement system.