• 환경영향평가
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• 제8권2호
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• pp.73-82
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• 1999

This study analyzed the relationship between NDVI(Normalized Difference Vegetation Index) and urban heat island in three cities: Daegu, Kyungju, and Pohang for understanding the degree of nature conservation concentrating in the transition zone of them. Daegu city is the third city in Korea which has a dense population. Kyungju is a traditional city which has good nature. Pohang is an industrial city which has those of characters of Daegu and Kyungju. Landsat 1M data in May 17, 1997 were used for the analysis of heat island. There were about four theoretical models to estimate the surface temperature from TM data: Two-point linear model, Linear regression model, Quadratic regression model, and Cubic regression model. In this study, Linear regression model had been utilized to analyze the urban heat island. On the resultant images, the transition zone of Daegu was urbanized more extremely than those of other two cities. It is thought that the analysis of relationship between NDVI and surface temperature, used in this study, is regarded as one of effective methodologies for urban-environmental detection from satellite imageries.

• ETRI Journal
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• 제31권2호
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• pp.162-172
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• 2009

A linear-prediction-based blind equalization algorithm for single-input single-output (SISO) finite impulse response/infinite impulse response (FIR/IIR) channels is proposed. The new algorithm is based on second-order statistics, and it does not require channel order estimation. By oversampling the channel output, the SISO channel model is converted to a special single-input multiple-output (SIMO) model. Two forward linear predictors with consecutive prediction delays are applied to the subchannel outputs of the SIMO model. It is demonstrated that the partial parameters of the SIMO model can be estimated from the difference between the prediction errors when the length of the predictors is sufficiently large. The sufficient filter length for achieving the optimal prediction is also derived. Based on the estimated parameters, both batch and adaptive minimum-mean-square-error equalizers are developed. The performance of the proposed equalizers is evaluated by computer simulations and compared with existing algorithms.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.460-460
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• 2000

Until now various model matching systems have been proposed for linear system, but very little has been done for nonlinear system In this paper, a design method of discrete time flight control system using nonlinear model matching is proposed. This method is based on Hirschorn's algorithm and facilitates easy determination of the control law using the relationship, between the output and the input, which is obtained by the time shift of the output. Also as a result, this method is the extension of the linear model matching control system proposed by Wolovich, in which the control law is obtained by left-multiplying the output by the interactor matrix. At the end of paper, the proposed control system is applied to CCV flight control system of an aircraft and the feasibility of the proposed approach is shown by the numerical simulations.

• 한국조경학회지
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• 제16권3호
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• pp.1-6
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• 1989

도시공원 계획에 관한 선형계획모형은 사람들의 선택행위를 명시적으로 고려할 수 없으며, 목적함수가 사람들의 만족을 총합하는데 있어서 불충분하다는 약점을 지니고 있다. 이와 같은 문제점들을 극복하기 위하여 본 논문에서는 다음과 같은 점들을 모색하였다. 공원에 대한 사람들의 선택행위를 명시적으로 고려하기 위하여 효용극대화를 전제로 행동하는 사람들의 선호관계에 입학한 이항 및 다향로짓(logit)모형을 구축하고 구축되어진 모형을 합리적으로 총합할 수 있는 사회후생함수를 목적함수로 설정하여, 도시공원 계획시 선형계획모형이 갖는 약점을 보완하였다. 향후 본 논문에서 분석된 모형을 활용함으로써 도시공원에 대한 최적투자 계획을 수립하는 것이 가능할 것으로 생각되며, 현재 도시공원의 최적 기준 설정에 관한 실증적 분석이 국내의 경우 거의 전무한 상황이다. 국민소득수준의 향상에 따른 위락시설 이용수요의 증가추세를 고려하는 경우 희소한 자원에 효율적 배분을 위하여 본 논문이 제시한 바와 같은 이론적 기준이 현실적으로 적용되어야 할 것이다.

• Advances in biomechanics and applications
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• 제1권3호
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• pp.169-185
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• 2014

Computational multibody models of the elbow can provide a versatile tool to study joint mechanics, cartilage loading, ligament function and the effects of joint trauma and orthopaedic repair. An efficiently developed computational model can assist surgeons and other investigators in the design and evaluation of treatments for elbow injuries, and contribute to improvements in patient care. The purpose of this study was to develop an anatomically correct elbow joint model and validate the model against experimental data. The elbow model was constrained by multiple bundles of non-linear ligaments, three-dimensional deformable contacts between articulating geometries, and applied external loads. The developed anatomical computational models of the joint can then be incorporated into neuro-musculoskeletal models within a multibody framework. In the approach presented here, volume images of two cadaver elbows were generated by computed tomography (CT) and one elbow by magnetic resonance imaging (MRI) to construct the three-dimensional bone geometries for the model. The ligaments and triceps tendon were represented with non-linear spring-damper elements as a function of stiffness, ligament length and ligament zero-load length. Articular cartilage was represented as uniform thickness solids that allowed prediction of compliant contact forces. As a final step, the subject specific model was validated by comparing predicted kinematics and triceps tendon forces to experimentally obtained data of the identically loaded cadaver elbow. The maximum root mean square (RMS) error between the predicted and measured kinematics during the complete testing cycle was 4.9 mm medial-lateral translational of the radius relative to the humerus (for Specimen 2 in this study) and 5.30 internal-external rotation of the radius relative to the humerus (for Specimen 3 in this study). The maximum RMS error for triceps tendon force was 7.6 N (for Specimen 3).

• Journal of the Korean Data and Information Science Society
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• 제21권6호
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• pp.1009-1020
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• 2010

본 연구에서 활용하는 안양시 교육 자료는 학생과 학교간이 위계적인 수준의 형태이기 때문에 상위 수준의 특성을 반영하는 위계적 선형모형을 이용하여 안양시 초등학교 학부모의 자녀가 다니는 학교에 대한 제반 여건들에 대한 만족도에 대한 영향요인 분석을 하였다. 그 결과 부모들이 느끼는 자녀의 학교여건 만족도에 부모들의 시 교육정책에 대한 만족 정도, 학군선호의 신도시 지역을 나타내는 학교의 거주지가 그 다음 크게 영향을 미쳤다. 위계적 선형모형의 분석 결과를 종합해 보면, 사교육 없이 공교육만으로 학생들에 대한 교육이 충분히 가능하도록 하고 신도시와 같이 학교의 제반 교육환경을 개선하는 방향으로 안양시의 교육정책을 펼쳐 나간다면 학부모의 자녀가 다니는 학교에 대한 제반 여건들에 대한 만족도는 지금보다는 더욱 향상될 것으로 보인다.

• Management Science and Financial Engineering
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• 제13권2호
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• pp.99-116
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• 2007

This paper considers the value of location in a linear city model and examines the product differentiation equilibrium of duopoly providing different benefits to consumers. We show that if the value of location is small, symmetric location equilibrium occurs where two firms follow the maximal differentiation principle. However, as the value of location increases, asymmetric location equilibrium occurs where the low-value-location firm moves to the high-value-location firm and thus adjusted maximal differentiation principle holds. We also investigate two different price leadership model and demonstrate the relationship between the value of location and the role of price leadership. In particular, we show that when the location value is high, the price leadership by high-value-location firm will appear as a unique equilibrium.

• Coupled systems mechanics
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• 제12권1호
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• pp.83-102
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• 2023

First introduced in 2016, the dynamic foundation model is an interesting topic in which the foundation is described close to reality by taking into account the influence of the foundation mass in the calculation of oscillation and is an important parameter that should be considered. In this paper, a follow-up investigation is conducted with the object of the Mindlin plate on a nonlinear dynamic foundation under moving loads. The base model includes nonlinear elastic springs, linear Pasternak parameters, viscous damping, and foundation mass. The problem is formulated by the finite element analysis and solved by the Newmark-β method. The displacement results at the center of the plate are analyzed and discussed with the change of various parameters including the nonlinear stiffness, the foundation mass, and the load velocity. The dynamic response of the plate sufficiently depends on the foundation mass.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2004년도 추계학술발표회 논문집
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• pp.179-184
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• 2004

High-resolution satellite imagery are used in various application field such as generation of DEM, orthophto, and three dimensional city model. To define the relation between image and object space, sensor modelling and generation of the epipolar image is essential processes. As the header information or physical sensor model becomes unavailable for the end users due to the national security or commercial purpose, generation of epipolar images without these information becomes one of important processes. In this study, epipolar geometry is generated and analysed by applying two generalized sensor models; parallel and parallel-perspective model Epipolar equation of the parallel model has linear property which is relatively simple; Epipolar geometry of the parallel-perspective model is non-linear. This linear property enable us to generate epipolar image efficiently.

• 산업기술연구
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• 제27권B호
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• pp.29-36
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• 2007

A comparative study of airborne salinity and sea wind was done for a coastal area, Sokcho city, of East Sea in Kangwon province, Korea. In this study, a relationship between the formation of airborne salinity and wind velocity was investigated, and then the airborne salinity was simulated and forecasted by the obtained wind-salinity characteristics. It is founded that most airborne salinity is brought by sea winds with the occurrence of velocity, higher than and equal to 4m/s, while the occurrence of lower wind velocities (ie., lower than 4m/s) in sea wind and the occurrence of inland wind give diluted effects on the airborne transfer. By using these characteristics and a proposed linear equation model, the salinity in Sokcho city is successfully simulated and forecasted. It is expected that the linear equation model may be useful for durability design of concrete structures under the conditions of chloride attack, induced by the airborne salinity.