• Title/Summary/Keyword: linear maps

Search Result 213, Processing Time 0.022 seconds

NONBIJECTIVE IDEMPOTENTS PRESERVERS OVER SEMIRINGS

  • Orel, Marko
    • Journal of the Korean Mathematical Society
    • /
    • v.47 no.4
    • /
    • pp.805-818
    • /
    • 2010
  • We classify linear maps which preserve idempotents on $n{\times}n$ matrices over some classes of semirings. Our results include many known semirings like the semiring of all nonnegative integers, the semiring of all nonnegative reals, any unital commutative ring, which is zero divisor free and of characteristic not two (not necessarily a principal ideal domain), and the ring of integers modulo m, where m is a product of distinct odd primes.

A RESULT OF LINEAR JORDAN DERIVATIONS ON NONCOMMUTATIVE BANACH ALGEBRAS

  • Chang, Ick-Soon
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.11 no.1
    • /
    • pp.123-128
    • /
    • 1998
  • The purpose of this paper is to prove the following result: Let A be a noncom mutative Banach algebra. Suppose that $D:A{\rightarrow}A$ is a continuous linear Jordan derivation such that $D^2(x)D(x)^2{\in}rad(A)$ for all $x{\in}A$. Then D maps A into its radical.

  • PDF

Comparison of Edge Detection using Linear Rank Tests in Images (영상에서 선형순위검정법을 이용한 에지검출 비교)

  • Lim Dong-Hoon
    • Journal of the Korea Society of Computer and Information
    • /
    • v.10 no.6 s.38
    • /
    • pp.17-26
    • /
    • 2005
  • In this paper we propose three nonparametric tests such as Wilcoxon test, Median test and Van der Waerden test, based on linear rank statistics for detecting edges in images. The methods used herein are based on detecting changes in gray-levels obtained using an edge-height parameter between two sub-regions in a 5$\times$5 window We compare and analysis the performance of three statistical edge detectors in terms of qualitative measures with the edge maps and objective, quantitative measures.

  • PDF

LINER STABILITY OF A PERIODIC ORBIT OF TWO-BALL LINEAR SYSTEMS

  • Chi, Dong-Pyo;Seo, Sun-Bok
    • Journal of the Korean Mathematical Society
    • /
    • v.36 no.2
    • /
    • pp.403-419
    • /
    • 1999
  • We introduce a Hamiltonian system which consists of two balls in the vertical line colliding elastically with each other and the floor. Wojtkowski proved that for the system of two linear balls with a linear potential (with gravity), there is a periodic orbit which becomes linearly stable if m1

  • PDF

Inundation Map at Imwon Port with Past and Virtual Tsunamis (과거 및 가상 지진해일에 의한 임원항의 침수예상도)

  • Kim, Tae-Rim;Cho, He-Rin;Cho, Yong-Sik
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.21 no.1
    • /
    • pp.1-9
    • /
    • 2017
  • The scale of disaster and damage witnessed in the 2004 Indian Ocean Tsunami and the 2011 Great East Japan Tsunami has motivated researchers in developing foolproof disaster mitigation techniques for safety of coastal communities. This study focuses on developing tsunami hazard map by numerical modeling at Imwon Port to minimize losses of human beings and property damage when a real tsunami event occurs. A hazard map is developed based on inundation maps obtained by numerical modeling of 3 past and 11 virtual tsunami cases. The linear shallow-water equations with manipulation of frequency dispersion and the non-linear shallow-water equations are employed to obtain inundation maps. The inundation map gives the maximum extent of expected flooded area and corresponding inundation depths which helps in identifying vulnerable areas for unexpected tsunami attacks. The information can be used for planning and developing safety zones and evacuation structures to minimize damage in case of real tsunami events.

Fault diagnosis of linear transfer robot using XAI

  • Taekyung Kim;Arum Park
    • International Journal of Internet, Broadcasting and Communication
    • /
    • v.16 no.3
    • /
    • pp.121-138
    • /
    • 2024
  • Artificial intelligence is crucial to manufacturing productivity. Understanding the difficulties in producing disruptions, especially in linear feed robot systems, is essential for efficient operations. These mechanical tools, essential for linear movements within systems, are prone to damage and degradation, especially in the LM guide, due to repetitive motions. We examine how explainable artificial intelligence (XAI) may diagnose wafer linear robot linear rail clearance and ball screw clearance anomalies. XAI helps diagnose problems and explain anomalies, enriching management and operational strategies. By interpreting the reasons for anomaly detection through visualizations such as Class Activation Maps (CAMs) using technologies like Grad-CAM, FG-CAM, and FFT-CAM, and comparing 1D-CNN with 2D-CNN, we illustrates the potential of XAI in enhancing diagnostic accuracy. The use of datasets from accelerometer and torque sensors in our experiments validates the high accuracy of the proposed method in binary and ternary classifications. This study exemplifies how XAI can elucidate deep learning models trained on industrial signals, offering a practical approach to understanding and applying AI in maintaining the integrity of critical components such as LM guides in linear feed robots.

Application of the High Resolution Aerial Images to Estimate Nonpoint Pollution Loads in the Unit Load Approach (원단위법에 의한 비점오염부하량 산정 시 토지피복 특성을 반영하는 고해상도 항공영상의 활용방안)

  • Lee, Bum-Yeon;Lee, Chang-Hee;Lee, Su-Woong;Ha, Do
    • Journal of Environmental Impact Assessment
    • /
    • v.18 no.5
    • /
    • pp.281-291
    • /
    • 2009
  • In Total Water Pollutant Load Management System of Korea, unit load approach based on land register data is currently used for the estimation of non-point pollutant load. However, a problem raised that land register data could not always reflect the actual land surface coverages which determine runoff characteristics of non-point pollution sources. As a way to overcome this, we tried to establish quantitative relationships between the aerial images (0.4m resolution) which reflect actual land surface coverages and the land registration maps according to the 19 major designated land-use categories in Kyeongan watershed. Analyses showed different relationships according to the land-use categories. Only a few land-use categories including forestry, road and river showed essentially identical and some categories such as orchard, parking lot and sport utility site showed no relationships at all between image data and land register data. Except for the two cases, all the other categories showed statistically significant linear relationships between image data and land register data. The analyses indicate that using high resolution aerial maps is a better way to estimate non-point pollutant load. If the aerial maps are not available, application of the linear relationships as conversion factors of land register data to image data could be an possible option to estimate non-point pollutant loads for the specific land-use categories in Kyeongan watershed.

The Characteristics of Groundwater Quality in the Youngsan and Sumjin River Basins Using Geostatistical Methods (지구통계 기법을 이용한 영산강.섬진강 유역의 지하수 수질특성 연구)

  • 정상용;심병완;김규범;강동환;박희영
    • Journal of the Korean Society of Groundwater Environment
    • /
    • v.7 no.3
    • /
    • pp.125-132
    • /
    • 2000
  • pH, EC and TDS are basic components in the investigation of groundwater quality, and are very important to the preliminary assessment of groundwater quality. These three chemical components investigated at the Youngsan and Sumjin river basins in 1998 suggest that the groundwater quality is generally good in these basins. Linear regression analysis shows that TDS versus EC has an linear correlation, but EC versus pH, and TDS versus pH have nearly no correlation. The relation of TDS and EC is 1.0 mg/1=1.52 $mu\textrm{S}$/cm, and it is the quality of natural water. In geostatistical analysis. three kinds of data are stationary random functions and they have exponential variograms. According to the isopleth maps of the groundwater quality, the groundwater quality of the Youngsan river basin is more contaminated than that of the Sumjin river basin. The isopleth maps of TDS and EC show very similar patterns because of the strong correlation between TDS and EC. The minimum and maximum values of the groundwater quality data are not reflected on the isopleth maps because kriging produces smooth distributions with minimum estimation variances.

  • PDF

Design of image encryption system using multiple chaotic maps (다중 카오스 사상을 이용한 영상 암호시스템 설계)

  • 이성우;신재호
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.14 no.4
    • /
    • pp.183-194
    • /
    • 2004
  • The proliferation of the Internet and the rapid progress of wire/wireless communication technology makes security of digital images more and more important since the exchanges of digital images occur more and more frequently. And as the tight relationship between chaos theory and cryptography, many researches for development of new encryption systems based on chaotic maps have been widely progressed recently. In this paper, we propose a digital image encryption system based on both one-dimensional PLCM(Piecewise Linear Chaotic Map) and two-dimensional baker map. This proposed system is a product cipher that contains a perturbance-based chaotic stream cipher based on ID PLCM and a chaotic block cipher based on 2D baker map and is very high secure and easily implementable cipher having both a good confusion property and a good diffusion property. And with test results, we showed this system is very secure against statistical attacks.