• Title/Summary/Keyword: uniform reference points

Search Result 12, Processing Time 0.021 seconds

A random forest-regression-based inverse-modeling evolutionary algorithm using uniform reference points

  • Gholamnezhad, Pezhman;Broumandnia, Ali;Seydi, Vahid
    • ETRI Journal
    • /
    • v.44 no.5
    • /
    • pp.805-815
    • /
    • 2022
  • The model-based evolutionary algorithms are divided into three groups: estimation of distribution algorithms, inverse modeling, and surrogate modeling. Existing inverse modeling is mainly applied to solve multi-objective optimization problems and is not suitable for many-objective optimization problems. Some inversed-model techniques, such as the inversed-model of multi-objective evolutionary algorithm, constructed from the Pareto front (PF) to the Pareto solution on nondominated solutions using a random grouping method and Gaussian process, were introduced. However, some of the most efficient inverse models might be eliminated during this procedure. Also, there are challenges, such as the presence of many local PFs and developing poor solutions when the population has no evident regularity. This paper proposes inverse modeling using random forest regression and uniform reference points that map all nondominated solutions from the objective space to the decision space to solve many-objective optimization problems. The proposed algorithm is evaluated using the benchmark test suite for evolutionary algorithms. The results show an improvement in diversity and convergence performance (quality indicators).

Method of Making the Distribution of Voxels Uniform within the Volumetric 3D image Space

  • Lin, Yuanfang;Liu, Xu;Xie, Xiaoyan;Liu, Xiangdong;Li, Haifeng
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2008.10a
    • /
    • pp.1138-1141
    • /
    • 2008
  • By defining a uniform reference point array corresponding to the 3D voxel array and abandoning voxels whose deviations from their respective reference points exceed a given tolerance, the distribution of voxels within the volumetric 3D image space gets uniform, effects of non-uniform distribution upon the image reconstructing are eased.

  • PDF

Automatic Extraction Method of Control Point Based on Geospatial Web Service (지리공간 웹 서비스 기반의 기준점 자동추출 기법 연구)

  • Lee, Young Rim
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.22 no.2
    • /
    • pp.17-24
    • /
    • 2014
  • This paper proposes an automatic extraction method of control point based on Geospatial Web Service. The proposed method consists of 3 steps. 1) The first step is to acquires reference data using the Geospatial Web Service. 2) The second step is to finds candidate control points in reference data and the target image by SURF algorithm. 3) By using RANSAC algorithm, the final step is to filters the correct matching points of candidate control points as final control points. By using the Geospatial Web Service, the proposed method increases operation convenience, and has the more extensible because of following the OGC Standard. The proposed method has been tested for SPOT-1, SPOT-5, IKONOS satellite images and has been used military standard data as reference data. The proposed method yielded a uniform accuracy under RMSE 5 pixel. The experimental results proved the capabilities of continuous improvement in accuracy depending on the resolution of target image, and showed the full potential of the proposed method for military purpose.

Robust Radiometric and Geometric Correction Methods for Drone-Based Hyperspectral Imaging in Agricultural Applications

  • Hyoung-Sub Shin;Seung-Hwan Go;Jong-Hwa Park
    • Korean Journal of Remote Sensing
    • /
    • v.40 no.3
    • /
    • pp.257-268
    • /
    • 2024
  • Drone-mounted hyperspectral sensors (DHSs) have revolutionized remote sensing in agriculture by offering a cost-effective and flexible platform for high-resolution spectral data acquisition. Their ability to capture data at low altitudes minimizes atmospheric interference, enhancing their utility in agricultural monitoring and management. This study focused on addressing the challenges of radiometric and geometric distortions in preprocessing drone-acquired hyperspectral data. Radiometric correction, using the empirical line method (ELM) and spectral reference panels, effectively removed sensor noise and variations in solar irradiance, resulting in accurate surface reflectance values. Notably, the ELM correction improved reflectance for measured reference panels by 5-55%, resulting in a more uniform spectral profile across wavelengths, further validated by high correlations (0.97-0.99), despite minor deviations observed at specific wavelengths for some reflectors. Geometric correction, utilizing a rubber sheet transformation with ground control points, successfully rectified distortions caused by sensor orientation and flight path variations, ensuring accurate spatial representation within the image. The effectiveness of geometric correction was assessed using root mean square error(RMSE) analysis, revealing minimal errors in both east-west(0.00 to 0.081 m) and north-south directions(0.00 to 0.076 m).The overall position RMSE of 0.031 meters across 100 points demonstrates high geometric accuracy, exceeding industry standards. Additionally, image mosaicking was performed to create a comprehensive representation of the study area. These results demonstrate the effectiveness of the applied preprocessing techniques and highlight the potential of DHSs for precise crop health monitoring and management in smart agriculture. However, further research is needed to address challenges related to data dimensionality, sensor calibration, and reference data availability, as well as exploring alternative correction methods and evaluating their performance in diverse environmental conditions to enhance the robustness and applicability of hyperspectral data processing in agriculture.

A Study on Present Conditions and Characteristics of Cadastral Surveying Accuracy in Korea (우리나라 지적측량 정확도의 현황과 특성)

  • Yoon, Ha-Su;Choi, Yun-Soo;Son, Jong-Young;Kim, Jae-Myeong
    • Spatial Information Research
    • /
    • v.19 no.5
    • /
    • pp.27-35
    • /
    • 2011
  • The current cadastral surveying is used digital cadastral map. This map is no local confirmation. Besides, Base cadastral map drawn up 100 years ago. And Graphical cadastral characteristic is difficult to ground boundary points restoration. Due to the lack of ground boundary points can cause land dispute and Cadastral Non-Coincidence. In this Study, Understand the concept of accuracy and error, Analyzing the current regulations. Also Comparative analysis of current cadastral regulations and other surveying regulations to suggest improvements to the cadastral surveying. The results indicated a clear definition of accuracy and error and The installation of permanent ground boundary points are needed. Uniform and consistent reference point system is needed. In addition, the accuracy provided by the landowner should understand. Cadastral Surveying Regulations require specific and detailed procedures.

Exergetic analysis for optimization of a rotating equilateral triangular cooling channel with staggered square ribs

  • Moon, Mi-Ae;Kim, Kwang-Yong
    • International Journal of Fluid Machinery and Systems
    • /
    • v.9 no.3
    • /
    • pp.229-236
    • /
    • 2016
  • Exergetic analysis was introduced in optimization of a rotating equilateral triangular internal cooling channel with staggered square ribs to maximize the net exergy gain. The objective function was defined as the net exergy gain considering the exergy gain by heat transfer and exergy losses by friction and heat transfer process. The flow field and heat transfer in the channel were analysed using three-dimensional Reynolds-averaged Navier-Stokes equations under the uniform temperature condition. Shear stress transport turbulence model has been selected as a turbulence closure through the turbulence model test. Computational results for the area-averaged Nusselt number were validated compared to the experimental data. Three design variables, i.e., the angle of rib, the rib pitch-to-hydraulic diameter ratio and the rib width-to-hydraulic diameter ratio, were selected for the optimization. The optimization was performed at Reynolds number, 20,000. Twenty-two design points were selected by Latin hypercube sampling, and the values of the objective function were evaluated by the RANS analysis at these points. Through optimization, the objective function value was improved by 22.6% compared to that of the reference geometry. Effects of the Reynolds number, rotation number, and buoyancy parameter on the heat transfer performance of the optimum design were also discussed.

The Applicability of the UNIDROIT Principles as the "Lex Mercatoria" in International Commercial Arbitration (국제상사중재에서 UNIDROIT 원칙의 적용가능성에 관한 연구)

  • Lee, Dae-Jin;Yu, Byoung-Yook;Oh, Hyon-Seok
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
    • /
    • v.21
    • /
    • pp.129-151
    • /
    • 2003
  • Nowadays even if environment of international commercial transaction is changing quickly municipal law could not meet with such change accordingly. So far, however, efforts towards unification have prevailingly taken the form of binding instruments, such as non-national or supranational legislation, international conventions or international model laws. Among them, the UNIDROIT Principles with parties' autonomous and yet non-binding character do not only meet the substantive requirements of a true law merchant. In addition they also counter some of the main points of criticism against the modern lex mercatoria. As such the Principles constitute a cornerstone in the lex mercatoria debate and may become the heart of the new lex mercatoria. The purpose of this article is to ask whether there could be applied the Principles in international commerce. For the purpose it is to investigate when the Principles are applied in international commerce and how effectively the Principles are applied for the decision in international commercial disputes. Even though the Principles are used for reference by parties involved for the voluntary regulation of their contract, it is sufficiently expected that the Principles are to be a stepstone of uniform contract law in international commerce. Until now cases of appling the Principles are not satisfied with its expectation as a source of non-legislative means of unification or harmonization of law. Given the party's autonomy in the contract, this is among other things because business parties are strongly tend to observe their national laws in their international commerce. And also, even though there are a number of neutral and uniform regulations for international commercial contracts, parties do not often recognize their usefulness with being up to expectation. In order to explore the applicability of the Principles a number of cases of ICC International Court of Arbitration and others are quoted.

  • PDF

Robust Watermarking Algorithm for 3D Mesh Models (3차원 메쉬 모델을 위한 강인한 워터마킹 기법)

  • 송한새;조남익;김종원
    • Journal of Broadcast Engineering
    • /
    • v.9 no.1
    • /
    • pp.64-73
    • /
    • 2004
  • A robust watermarking algorithm is proposed for 3D mesh models. Watermark is inserted into the 2D image which is extracted from the target 3D model. Each Pixel value of the extracted 2D image represents a distance from the predefined reference points to the face of the given 3D model. This extracted image is defined as “range image” in this paper. Watermark is embedded into the range image. Then, watermarked 3D mesh is obtained by modifying vertices using the watermarked range Image. In extraction procedure, the original model is needed. After registration between the original and the watermarked models, two range images are extracted from each 3D model. From these images. embedded watermark is extracted. Experimental results show that the proposed algorithm is robust against the attacks such as rotation, translation, uniform scaling, mesh simplification, AWGN and quantization of vertex coordinates.

A study on the functions of headings (표목의 기능에 관한 연구)

  • 김태수
    • Journal of the Korean Society for information Management
    • /
    • v.12 no.2
    • /
    • pp.9-35
    • /
    • 1995
  • Locating function of a particular item is more of added entry than a main entry heading. This function was expanded especially in the machine readable cataloging by introducing the control number and standard bibliographic number. Assembling function of the main entry heading is on a level with that of cross reference and notes, added entries, uniform headings. Links among all variant forms of a heading in hypercatalog will be made for collocating of all publications of a given author. The link of bibliographic records in this catalog can be freed from the dependence on standardized heading form. The function of the catalog is not affected even though by abandoning the concept of main entry heading. Further efforts should be made to raise users' finding opportunities through expansion of acces points and linking devices among related records.

  • PDF

Evaluation of Dosimetric Effect and Treatment Time by Plan Parameters for Endobronchial Brachytherapy

  • Choi, Chang Heon;Park, Jong Min;Park, So-Yeon;Kang, SungHee;Cho, Jin Dong;Kim, Jung-in
    • Progress in Medical Physics
    • /
    • v.28 no.2
    • /
    • pp.39-44
    • /
    • 2017
  • This study aims to analyze dose distribution and treatment time of endobronchial brachytherapy (EBBT) by changing the position step size of the dwell position. A solid water phantom and an intraluminal catheter were used in the treatment plan. The treatment plans were generated for 3, 5, 7, and 10 cm treatment lengths, respectively. For each treatment length, the source position step sizes were set as 2.5, 5, and 10 mm. Three reference points were set 1 cm away from the central axis of the catheter, along the axis, for uniform dose distribution. Volumetric dose distribution was calculated to evaluate the dosimetric effect. The total radiation delivery time and total dwell time were estimated for treatment efficiency, which were increased with position step sizes. At half-life time, the differences between the position step sizes in the total radiation delivery time were 18.1, 15.4, 18.0, and 24.0 s for 3, 5, 7, and 10 cm treatment lengths, respectively. The dose distributions were more homogenous by increasing the position step sizes. The dose difference of the reference point was less than 10%. In brachytherapy, this difference can be negligible. For EBBT, the treatment time is the key factor while considering the patient status. To reduce the total treatment time, EBBT can be performed with 2.5 mm position step size.