• 대한인간공학회지
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• 제32권3호
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• pp.217-227
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• 2013

Objective: The purpose of this study was to analyze 'response time', 'peak response time' and 'overshoot value' for each muscle by applying the EMG signal to the vehicle response in ISO 7401 and to quantify the response of the driver according to vehicle characteristics by comparing vehicle characteristics and muscle responses of the driver. Background: The Open-loop test defined in international standards ISO 7401 is the only method for evaluating the performance of the vehicle. However, this test was focused only on mechanical responses, not driver's ones. Method: One skilled male driver(22 yrs. experience) was participated in this experiment to measure muscle activities of the driver in transient state. Then the seven muscle signals were applied to calculate 'response time', 'peak response time', and 'overshoot value'. Results: In the analyses of the EMG data, the effects of vehicle type and muscle were statistically significant on the 'response time' and 'peak response time'. Also, the effects of vehicle type, muscle, and lateral acceleration level were statistically significant on the 'overshoot value' in this study. According to the analyses of the vehicle motion data, vehicle motion variable(LatAcc, Roll, YawVel) was statistically significant on the 'response time' and vehicle type, vehicle motion variable, and lateral acceleration level were statistically significant on the 'peak response time', respectively. Conclusion: In the analyses of the 'response time' and 'overshoot value', the data of muscle activities(EMGs) was better index that could evaluate the vehicle characteristic and performance than the data of vehicle motion. In case of peak response time, both EMG and vehicle motion data were good index. Application: The EMGs data from a driver might be applicable as index for evaluation of various vehicle performances based on this study.

• 한국지진공학회논문집
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• 제11권4호
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• pp.65-77
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• 2007

Site response analyses were performed based on equivalent linear technique using shear wave velocity profiles of 162 sites collected around the Korean peninsula. The site characteristics, particularly the shear wave velocities and the depth to the bedrock, are compared to those in the western United States. The results show that the site-response coefficients based on the mean shear velocity of the top 30m ($V_{S30}$) suggested in the current code underestimates the motion in short-period ranges and overestimates the motion in mid-period ranges. The current Korean code based on UBC is required to be modified considering site characteristics in Korea for the reliable estimation of site amplification. From the results of numerical estimations, new regression curves were derived between site coefficients ($F_{a}\;and\;F_{v}$) and the fundamental site periods, and site coefficients were grouped based on site periods with reasonable standard deviations compared to site classification based on $V_{S30}$. Finally, new site classification system and modification of design response spectra are recommended considering geotechnical characteristics in Korea.

• 조명전기설비학회논문지
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• 제19권1호
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• pp.175-181
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• 2005

본 논문에서는 자동화 시스템의 고속 정밀 제어를 위한 퍼지-PLL 제어기를 제안한다. 기존의 PLL 제어기는 넓은 데드존 때문에 지터 잡음을 발생하고, 긴 지연시간 때문에 고속 동작의 정밀제어에는 부적합 하다. 본 논문에서는 이러한 문제를 해결하기 위하여, 제어영역을 고속 제어와 정밀제어 영역으로 구분한다. 먼저 퍼지 제어 기법을 적용하여 신속한 과도응답을 수행하고, 오차가 설정된 범위에 진입하면 새로운 위상 주파수 검출기를 설계한 PLL 제어기를 사용하여 정밀제어를 수행한다. 제안된 다중 구조의 위상 주파수 검출기는 데드존과 지터 잡음을 개선하고, 상승 에지에서 동작하는 P-PFD와 하강 에지에서 동작하는 N-PFD로 구성하여 PLL의 응답 특성을 향상 시킨다.

• 한국기계가공학회지
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• 제18권5호
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• pp.1-8
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• 2019

Breath analysis using a portable device is better than the classical breath analysis system in terms of installation and operation. There is an increasing need to develop cost-effective equipment for testing gas sensors from the viewpoint of functionalities that can be applied applicable to portable devices. In the present study, an economical gas chamber for in-situ gas measurement is implemented with a single gas chamber without using expensive gas storage and control equipment; the gas response characteristics are analyzed using the above-described chamber. The main features of the implemented gas chamber are simple injection procedure, improved gas diffusion, easy measurement and cleaning, support for low-power mode measurement function for portable devices, and open source platform. Moreover, an analysis of gas response characteristics based on changes in sensor voltage show that the sensitivity and 90% response time are affected by the sensor voltage. Furthermore, the sensitivity graph has an inflection point in a specific range. The gas sensor applied in this study showed fast response speed and high sensitivity for sensor voltages of 3.0-3.5 V, regardless of the concentration of acetone gas, the target gas used in this study.

• 한국광학회지
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• 제6권4호
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• pp.266-273
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• 1995

칼라영상센서의 분광감응 특성은 칼라영상의 색을 결정하는 중요한 요인이 된다. 칼라영상센서의 분광특성을 간편하게 측정할 수 있는 장치를 제작하고 이를 사용하여 CCD 칼라 카메라의 분광특성을 조사하였다. 측정장치는 가시광선 영역내에서 단색광의 파장뿐만아니라 세기도 간편하게 조절할 수 있도록 제작된 광학부와 칼라영상센서의 출력신호를 디지탈값으로 처리하여 나타내는 색분석부로 구성되었다. 광학부에서 만들어진 단색광들에 대한 카메라의 출력값 R, G, B를 측정하였으며 이로부터 카메라의 연색성 및 선형성을 평가하였다. 이로써 제작된 측정장치가 칼라영상센서의 분광특성 측정 및 성능평가에 매우 유용함을 확인할 수 있었다.

• 한국화재소방학회논문지
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• 제23권4호
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• pp.98-103
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• 2009

본 논문은 연기감지기의 응답특성을 분석하여 주택용 화재감지기로 적합한지를 분석하고자 광전식연기감지기, 아날로그연기감지기, 단독경보형연기감지기를 시험체로 선정하여 UL 268에서 정하는 화재시험방법을 응용하여 화재성상(종이화재와 인화성액체화재)에 따른 연기감지기의 응답특성을 분석하고자 화재실험을 실시하였다. 실험결과 화재성상에 따라 연기감지기의 응답특성 차이가 나타나는 것을 확인할 수 있었다.

• 한국산업융합학회 논문집
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• 제5권1호
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• pp.21-26
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• 2002

Response time of actuator in a hydraulic system may be important and necessary to avoid failures and to improve the efficiency of operation. Flow restricting devices can result in a decrease in the peak pressure, but may change the response time. The response time has an important effect on both operator and operator perceived smoothness. The response time should correspond to how fast a system responds to a given disturbance at the system boundary, Occasionally the appropriate response time is not easily determined. This study is on the characteristics of response time in the hydraulic system.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.597-603
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• 2001

Control of pressure transients in a hydraulic system may be important and necessary to avoid failures and to improve the efficiency of operation. Flow restricting devices can result in a decrease in the peak pressure, but may change the response time. The response time has an important effect on both operator and operator perceived smoothness. The response time should correspond to how fast a system responds to a given disturbance at the system boundary. Occasionally the appropriate response time is not easily determined. This study is on the response time characteristics in the hydraulic system studied for the control of response time.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.789-795
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• 2014

In a demand response (DR) market run by independent system operators (ISOs), load aggregators are important market participants who aggregate small retail customers through various DR programs. A load aggregator can minimize the allocation cost by efficiently allocating its demand response resources (DRRs) considering retail customers' characteristics. However, the uncertain response behaviors of retail customers can influence the allocation strategy of its DRRs, increasing the economic risk of DRR allocation. This paper presents a risk-based DRR allocation method for the load aggregator that takes into account not only the physical characteristics of retail customers but also the risk due to the associated response uncertainties. In the paper, a conditional value-at-risk (CVaR) is applied to deal with the risk due to response uncertainties. Numerical results are presented to illustrate the effectiveness of the proposed method.

• Journal of Korean Neurosurgical Society
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• 제42권2호
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• pp.92-96
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• 2007

Objective : The authors have speculated that metastatic brain lesions from renal cell carcinoma (RCC) show diverse radiological patterns and tumor responses after Gamma knife surgery (GKS), and have hypothesized that these can be predicted from tumor radiological characteristics. The goal of the current study was to identify the radiological characteristics of RCC brain metastases and the predictors of initial radiosurgical response after GKS. Methods : A retrospective analysis was performed on 48 lesions in 18 patients with RCC brain metastasis treated by GKS. The radiological characteristics of these lesions in magnetic resonance images (MRI) were classified into 3 categories according to enhancement patterns in T1-weighted images and signal intensity characteristics in T2-weighted images. Responses to GKS were analyzed according to these categories, and in addition, other potential predictive factors were also evaluated. Results : MRI findings in the three categories were diverse, though numbers of the lesion were comparable. At 2-month MRI follow-ups after GKS, response rate was 54% and the local tumor control rate 83%. T2 signal intensity was found to be the principal predictive factor of response to GKS, namely negative predictive factor. Other variables such as age, sex, tumor volume, dose, duration from initial diagnosis to GKS, and previous systemic therapies failed to show significant relationships with treatment response by multivariate analysis. Conclusion : Careful evaluation of the radiological characteristics of brain metastases from RCC is important prior to GKS because MRI heterogeneity has predictive value in terms of determining initial tumor response.