• 한국습지학회지
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• 제11권2호
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• pp.107-121
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• 2009

현재 홍수예보를 위하여 많은 강우-유출 모형이 사용되고 있으나, 이러한 모형의 매개변수를 결정하는 것은 매우 난해하다. 본 연구에서는 저류함수모형과 Tank 모형, SSARR 모형을 이용하여 미호천 유역에 대하여 홍수모의 예측을 수행하고 그 효율성을 분석하였다. 연구에 적용된 강우-유출 모형에 최적화 방법을 적용하여 매개 변수 산정을 수행하였으며, 패턴탐색과 유전자 알고리즘의 최적화 방법을 적용 시, 보정과정 내에서 매개변수 간 민감도를 분석하고 이를 바탕으로 매개변수를 소군집으로 분류하여 민감도에 따른 순차 보정 방법을 적용하고 이 결과를 비교 분석하였다. 매개변수 소군집을 이용한 보정 방법과 기존에 사용되는 매개변수 군집을 이용한 보정 방법을 비교한 결과, SSR에 소군집을 이용한 순차보정 방법을 적용하였을 때 첨두 유량과 보정 시간 면에서 유리한 것으로 나타났다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.1173-1177
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• 1990

Cerebellar Model Linear Associator Net(CMLAN), a kind of neuro-net based adaptive control function generator, was applied to the problem of direct inverse calibration of three and six d.o.f. POMA 560 robot. Since CMLAN autonomously maps and generalizes a desired system function via learning on the sampled input/output pair nodes, CMLAN allows no knowledge in system modeling and other error sources. The CMLAN based direct inverse calibration avoids the complex procedure of identifying various system parameters such as geometric(kinematic) or nongeometric(dynamic) ones and generates the corresponding desired compensated joint commands directly to each joint for given target commands in the world coordinate. The generated net outputs automatically handles the effect of unknown system parameters and dynamic error sources. On-line sequential learning on the prespecified sampled nodes requires only the measurement of the corresponding tool tip locations for three d.o.f. manipulator but location and orientation for six d.o.f. manipulator. The proposed calibration procedure can be applied to any robot.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(5)
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• pp.195-198
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• 2001

We developed the portable blood analysis system, which can be measured pH of the blood. This system is composed to electronic circuit, mechanism, and system software. Electronic circuit is composed to the sensor, pre-amp part, temperature regulation part, fluid sensing part, A/D(analog to digital) conversion part, main and peripheral device processing part. And the mechanism is composed to the flow cell and the liquid flow part. The liquid flow part is consisted of blood and washing control system under the control of the 6-channel solenoid valve and syringe rump. The system software is composed to measurement program, calibration program, washing and diagnostic program. The program of each routine is designed as sequential process for an efficiency. And the portable pH analysis system used two-point calibration method using the two types of corrective liquid. As a result, we obtained the calibration curve and calculated the value of pH. For verifying the system, we confirmed the output voltage of the sensor, and estimated reappearance of system using the standard liquid.

• 한국자동차공학회논문집
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• 제16권1호
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• pp.134-143
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• 2008

The hardware scatters as well as the engine parameters calibration have strong influences on exhaust emissions in recent diesel engines. In this research DoE(Design of Experiments) optimizations were done to study the possibility of minimizing the emission deviations caused by flow rate scatters of the injectors. It has been shown that the optimization of engine calibration, which minimizes the emission deviations, is feasible by establishing a target function representing the emission deviations for test results of maximum, mean and minimum flow rate injectors. It has also been shown that optimization of both emission deviations and emission level is possible by sequential DoE optimizations of the target functions representing the emission level and the emission deviations respectively with the appropriate boundary limits.

• 한국정밀공학회지
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• 제32권7호
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• pp.643-651
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• 2015

Multi-axis magnetic and accelerometer sensor are widely used in consumer product such as smart phones. The vector output of multi-axis sensors have errors on each axis such as offset error, scale error, non-orthogonality. These errors cause many problems on the performance of the applications. In this paper, we designed the effective inline compensation algorithm for calibrating of 3 axis sensors using ellipsoid for mass production of multi-axis sensors. The outputs with those kinds of errors can be modeled by ellipsoid, and the proposed algorithm makes sequential mappings of the virtual ellipsoid to perfect sphere which is calibrated function of the sensor on three-dimensional space. The proposed calibrating process composed of four main stages and is very straightforward and effective. In addition, another imperfection of the sensor such as the drift from temperature can be easily inserted in each mapping stage. Numerical simulation and experimental results shows great performance of the proposed compensation algorithm.

• 해양환경안전학회지
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• 제24권3호
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• pp.295-301
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• 2018

This study compares optimization algorithms for efficient estimations of ship's hydrodynamic coefficients. Two constrained algorithms, the interior point and the sequential quadratic programming, are compared for the estimation. Mathematical optimization is designed to get optimal hydrodynamic coefficients for modelling a ship, and benchmark data are collected from sea trials of a training ship. A calibration for environmental influence and a sensitivity analysis for efficiency are carried out prior to implementing the optimization. The optimization is composed of three steps considering correlation between coefficients and manoeuvre characteristics. Manoeuvre characteristics of simulation results for both sets of optimized coefficients are close to each other, and they are also fit to the benchmark data. However, this similarity interferes with the comparison, and it is supposed that optimization conditions, such as designed variables and constraints, are not sufficient to compare them strictly. An enhanced optimization with additional sea trial measurement data should be carried out in future studies.

• 한국농공학회논문집
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• 제60권1호
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• pp.47-57
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• 2018

This study implemented the rainfall-runoff analysis of the Mekong River basin using the SWAT (Soil and Water Assessment Tool). The runoff analysis was simulated for 2000~2007, and 11 parameters were calibrated using the SUFI-2 (Sequential Uncertainty Fitting-version 2) algorithm of SWAT-CUP (Calibration and Uncertainty Program). As a result of analyzing optimal parameters and sensitivity analysis for 6 cases, the parameter ALPHA_BF was found to be the most sensitive. The reproducibility of the rainfall-runoff results decreased with increasing number of stations used for parameter calibration. The rainfall-runoff simulation results of Case 6 showed that the RMSE of Nong Khai and Kratie stations were 0.97 and 0.9, respectively, and the runoff patterns were relatively accurately simulated. The runoff patterns of Mukdahan and Khong Chaim stations were underestimated during the flood season from 2004 to 2005 but it was acceptable in terms of the overall runoff pattern. These results suggest that the combination of SWAT and SWAT-CUP models is applicable to very large watersheds such as the Mekong for rainfall-runoff simulation, but further studies are needed to reduce the range of modeling uncertainty.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 2000년도 춘계학술대회논문집
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• pp.135-143
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• 2000

COCOMO II 모델은 비순차적이며, 빠른 개발방법 과정 등의 새로운 소프트웨어 생명주기에 적합한 비용 모델이다. COCOMO II 모델에서 조율 방법으로 널리 사용된 최소자승 회귀분석 방법은 소프트웨어공학 데이터 셀과 가정이 위배되는 점이 있다 즉, 원시자료는 특히 서로 다른 개발조직으로부터 비용인자 등급, 노력, 크기가 수집되며 부정확하고 이상치가 존재한다. 본 논문에서는 이러한 한계를 극복하기 위하여 우리는 COCOMO II 모델을 가지고 상대오차를 최소화하는 모델 조율에 대한 새로운 방법을 제안한다. 제안된 방법의 특징은 이상치를 갖는 원시 데이터에 덜 민감한 특성을 갖고 있다. 실험결과, 제안된 새로운 조율방법 MRE가 조정된 결정계수(adj-$R^2$), 표준편차(^$\sigma$), 예측 정도( PRED(L))에서 기존의 전통적 회귀분석 방법보다 우수하게 나타났다.

• 한국산업정보학회논문지
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• 제5권2호
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• pp.47-55
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• 2000

개발하는 소프트웨어의 비용, 스케줄 및 노력을 예측하기 위하여 오늘날 많은 소프트웨어 비용 모델이 개발되었다. COCOMO II은 비순차적이며, 빠른 개발방법 과정 등의 새로운 소프트웨어 생명주기에 적합한 비용 모델이다. COCOMO II모델에서 최소자승 회귀분석 방법은 조율 방법으로 널리 사용되었다. 전통적인 회귀분석 조율 방법은 데이터 ？에 대한 가정이 위배된다. 즉, 원시자료는 특히 서로 다른 개발조직으로부터 비용인자 등급, 노력, 크기가 수집되며 부정확하고 이상치가 존재한다. 본 논문에서는 이러한 한계를 극복하기 위하여 우리는 COCOMO II모델을 가지고 상대오차를 최소화하는 모델 조율에 대한 새로운 방법을 제안한다. 제안된 방법의 특징은 이상치를 갖는 원시 데이터에 덜 민감한 특성을 갖고 있다. 실험결과, 제안된 새로운 조율방법 MRE가 조정된 결정계수(adj-$R^2$), 표준편차(^$\sigma$), 예측 정도(PRED(L))에서 기존의 전통적 회귀분석 방법보다 우수하게 나타났다.

• 한국물환경학회지
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• 제29권5호
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• pp.681-690
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• 2013

Watershed models have been increasingly used to support an integrated management of land and water, non-point source pollutants, and implement total daily maximum load policy. However, these models demand a great amount of input data, process parameters, a proper calibration, and sometimes result in significant uncertainty in the simulation results. For this reason, uncertainty analysis is necessary to minimize the risk in the use of the models for an important decision making. The objectives of this study were to evaluate three different uncertainty analysis algorithms (SUFI-2: Sequential Uncertainty Fitting-Ver.2, GLUE: Generalized Likelihood Uncertainty Estimation, ParaSol: Parameter Solution) that used to analyze the sensitivity of the SWAT(Soil and Water Assessment Tool) parameters and auto-calibration in a watershed, evaluate the uncertainties on the simulations of runoff and sediment load, and suggest alternatives to reduce the uncertainty. The results confirmed that the parameters which are most sensitive to runoff and sediment simulations were consistent in three algorithms although the order of importance is slightly different. In addition, there was no significant difference in the performance of auto-calibration results for runoff simulations. On the other hand, sediment calibration results showed less modeling efficiency compared to runoff simulations, which is probably due to the lack of measurement data. It is obvious that the parameter uncertainty in the sediment simulation is much grater than that in the runoff simulation. To decrease the uncertainty of SWAT simulations, it is recommended to estimate feasible ranges of model parameters, and obtain sufficient and reliable measurement data for the study site.