• Journal of Intelligence and Information Systems
• /
• v.1 no.2
• /
• pp.1-16
• /
• 1995

The field of human judgment and decision making provides useful methodologies for examining the human decision making process and substantive results. One of the methodologies is a lens model analysis which can examine valid nonlinearity in the human decision making process. Using the method, valid nonlinearity in human decision behavior can be successfully detected. Two linear(statistical) models of human experts and two nonlinear models of human experts are compared in terms of predictive accuracy (predictive validity). The results indicate that nonlinear models can capture factors(valid nonlinearity) that contribute to the expert's predictive accuracy, but not factors (inconsistency) that detract from their predictive accuracy. Then, it is argued that nonlinear models cab be more accurate than linear models, or as accurate as human experts, especially when human experts employ valid nonlinear strategies in decision making.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.7 no.4
• /
• pp.64-72
• /
• 1998

This paper a new approach to the design of machine vision technique with a camera modeling that accounts for major sources of geometric distortion, namely, radial, decentering, and thin prism distortion. Radial distortion causes an inward or outward displacement of a given image point from its ideal location. Actual optical systems are subject to various degrees of decentering , that is , the optical centers of lens design and manufacturing as well as camera assembly. It is our propose to develop the vision system for the pattern recognition and the automatic test of parts and to apply the line of manufacturing. The performance of proposed vision system is illustrated by simulation and experiment.

• Korean Journal of Optics and Photonics
• /
• v.12 no.3
• /
• pp.240-249
• /
• 2001

A high speed ultra-compact lens with a diffractive optical element (DOE) is designed, which can be applied to mobile communication devices such as IMT2000, PDA, notebook computer, etc. The designed hybrid lens has sufficiently high performance of less than f/2.2, compact size of 3.3 mm (1st surf. to image), and wide field angle of more than 30 deg. compared with the specifications of a single lens. By proper choice of the aspheric and DOE surface which has very large negative dispersion, we can correct chromatic and high order aberrations through the optimization technique. From Seidel third order aberration theory and Sweatt modeling, the initial data and surface configurations, that is, the combination condition of the DOE and the aspherical surface are obtained. However, due to the consideration of diffraction efficiency of a DOE, we can choose only four cases as the optimization input, and present the best solution after evaluating and comparing those four cases. On the other hand, we also report dramatic improvement in optical performance by inserting another refractive lens (so-called, field flattener), that keeps the refractive power of an original DOE lens and makes the petzval sum zero in the original DOE lens system. ystem.

• Journal of The Korean Association For Science Education
• /
• v.36 no.2
• /
• pp.279-293
• /
• 2016

The purpose of this study was to analyze the effect of infographic instruction to promote the use of the scientific model in the 'lens' unit of elementary science textbooks. The participants were $6^{th}$ grade students(n=53) of G elementary school in G city, Gyeongsangnam-do. For this study, the lesson plan of the 'lens' unit consisted of three steps as investigation of students' prior concept about the lens, scientific model construction activity, and infographic construction activity. We then analyzed the results of this study from three perspectives: the scientific concept, scientific model, and infographic. Before the lesson, students focused on the external shape and material of the lens in prior concept of it. However, after the scientific model construction activity and infographic construction activity, students' scientific concept about the lens improved in the categories of features of lens, features of glasses, light path, and applications of the lens. In terms of the scientific model, use of type and frequency of scientific model increased more in the infographic construction activity than the scientific construction model activity. Also, in terms of infographic, the two infographic types as function based infographic and connection based infographic used more than non-infographic in the infographic construction activity. Also, the frequency of Gestal theory's visual perception increased more in the infographic construction activity than the scientific model construction activity.

• Journal of the Optical Society of Korea
• /
• v.19 no.2
• /
• pp.136-143
• /
• 2015

Image deblurring by a deconvolution method requires accurate knowledge of the blur kernel. Existing point spread function (PSF) models in the literature corresponding to lens aberrations and defocus are either parameterized and spatially invariant or spatially varying but discretely defined. In this paper, a parameterized model is developed and presented for a PSF which is spatially varying due to lens aberrations and defocus in an imaging system. The model is established from the Seidel third-order aberration coefficient and the Hu moment. A skew normal Gauss model is selected for parameterized PSF geometry structure. The accuracy of the model is demonstrated with simulations and measurements for a defocused infrared camera and a single spherical lens digital camera. Compared with optical software Code V, the visual results of two optical systems validate our analysis and proposed method in size, shape and direction. Quantitative evaluation results reveal the excellent accuracy of the blur kernel model.

• Journal of Korea Water Resources Association
• /
• v.55 no.9
• /
• pp.657-668
• /
• 2022

With the occurrence of localized heavy rain while river flow has increased, both flow and rainfall cause riverside flood damages. As the degree of damage varies according to the level of social and economic impact, it is required to secure sufficient forecast lead time for flood response in areas with high population and asset density. In this study, the author established a flood risk matrix using ensemble rainfall runoff modeling and evaluated its applicability in order to increase the damage reduction effect by securing the time required for flood response. The flood risk matrix constructs the flood damage impact level (X-axis) using flood damage data and predicts the likelihood of flood occurrence (Y-axis) according to the result of ensemble rainfall runoff modeling using LENS rainfall data and as well as probabilistic forecasting. Therefore, the author introduced a method for determining the impact level of flood damage using historical flood damage data and quantitative flood damage assessment methods. It was compared with the existing flood warning data and the damage situation at the flood warning points in the Taehwa River Basin and the Hyeongsan River Basin in the Nakdong River Region. As a result, the analysis showed that it was possible to predict the time and degree of flood risk from up to three days in advance. Hence, it will be helpful for damage reduction activities by securing the lead time for flood response.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2010.06a
• /
• pp.162-162
• /
• 2010

In this study, optical analysis for 100W LED safety street lighting was conducted. Experimental research on such single LED was the first undertaken. simulation modeling based on optical properties of single LED has compared single LED product also designed 100W simulation modeling has compared average road illuminance with Korean Industrial Standards for LED safety street lighting(KS C7658:2009). 100W safety street lighting (model: CE180-ST-OS) designed by simulation has been also compared between product and 100W simulation modeling, and error rates have showed average 5.6[%]. Designed 100W LED safety street lighting base on simulation modeling was proven by comparison experiments. Through the simulations and the corresponding analysis, it was found that the tested 100W LED safety street lamp had reasonable performance. Design method for LED safety Street lamps have been summarized, based on the optical analysis.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.16 no.3
• /
• pp.44-49
• /
• 2007

Recent manufacturing system requires development on new production technology to enable prompt manufacturing of diverse products. Most of the researchers have been working on micro-factory. Especially, focus on manufacturing of micro parts. Present manufacturing system consumes excessive resources in the form of energy and space to manufacture the micro parts. In this study, the micro lens module assembly system was modeled, analyzed with MST(Micro System Technology) Application Module and simulated through UML Language (Unified Modeling Language) with object-oriented logical model analysis method. Digital model of micro-factory was modeled, to execute the new paradigm of digitalization on products, resources and processes of micro-factory.

• The Journal of Bigdata
• /
• v.2 no.1
• /
• pp.41-48
• /
• 2017

Recently, the popularity of the recommendation system and the evaluation of the performance of the algorithm of the recommendation system have become important. In this study, we used modeling and RMSE to verify the effectiveness of various algorithms in movie data. The data of this study is based on user-based collaborative filtering using Pearson correlation coefficient, item-based collaborative filtering using cosine correlation coefficient, and item-based collaborative filtering model using singular value decomposition. As a result of evaluating the scores with three recommendation models, we found that item-based collaborative filtering accuracy is much higher than user-based collaborative filtering, and it is found that matrix recommendation is better when using matrix decomposition.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.23 no.6
• /
• pp.527-532
• /
• 2013

Depth estimation is an essential factor for robot vision, 3D scene modeling, and motion control. The depth estimation method is based on focusing values calculated in a series of images by a single camera at different distance between lens and object. In this paper, we proposed a relative depth estimation method using focus measure. The proposed method is implemented by focus value calculated for each image obtained at different lens position and then depth is finally estimated by considering relative distance of two patterns. We performed various experiments on the effective focus measures for depth estimation by using various patterns and their usefulness.