UBV photometry of two physical systems of galaxies with ultraviolet excess

Red colours: B–V=+1.23, U-B = + 1.03 and short period: P=0.2207 days place CC Com at the lower temperature end of the period-colour relation for the W UMa-type binaries. Contrary to the typical behaviour of (B–V) which shows reddening during both minima, the (U–B) index reveals rather large scatter, especially when different nights are intercompared. In addition (U–B) seems to decrease abnormally during some of primary minima when the colours change to B–V = + 1.29 and U–B = +0.99; it is unclear whether the ultraviolet excess δ(U–B) of about +0.11 is not related to these changes. Small night-to-night changes seem to be present in the V-light curve as well.The large amplitudes of light variations (0.86 and 0.74 mag) and the presence of total eclipses with semi-duration of about 7 deg in phase permit to determine the geometrical elements with rather high accuracy in spite of larger than normal observational errors due to the faintness of the system (V= 11.3-12.2). CC Com belongs to the W-type systems with the relative temperature excess of secondary component X= +0.058 ± 0.002. Other elements are: i = 8806 ± 0.09, q = 0.511 ± 0.009, f = 0.78 ± 0.03 for the assumed Te0 = 4300 K. To obtain a perfect fit to the light curve, the gravity darkening exponent was also varied with the resulting value β = 0.09 ± 0.02.There are indications that CC Com might belong to the Coma cluster.

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On the Connection Between Galaxies with Ultraviolet Excess

Communications of the Byurakan Astrophysical Observatory ◽

10.52526/25792776-2018.2.2-417 ◽

2018 ◽

pp. 417-420

Author(s):

A. A. Yeghiazaryan

Keyword(s):

Ultraviolet Excess ◽

Characteristic Parameters ◽

Physical Systems ◽

Mutually Independent

A possible correlation between the characteristic parameters of physically coupled galaxies with ultraviolet excess is discussed. It is known that for mutually independent combinations the observed number of galactic pairs with Markarian components is greater than expected. It is shown, that the most of nearby Kazarian galaxies with ultraviolet excess form physical systems.

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Emerging Cyber-Physical Systems : An Overview

International Journal of Scientific Research in Computer Science Engineering and Information Technology ◽

10.32628/cseit183862 ◽

2018 ◽

pp. 306-316

Author(s):

Okolie S.O. ◽

Kuyoro S.O. ◽

Ohwo O. B

Keyword(s):

Health Care ◽

Economic Benefit ◽

Physical World ◽

Cyber Physical Systems ◽

Cyber Physical System ◽

Economic Sectors ◽

Strategic Research ◽

Physical Systems ◽

Security Issues ◽

Wide Range

Cyber-Physical Systems (CPS) will revolutionize how humans relate with the physical world around us. Many grand challenges await the economically vital domains of transportation, health-care, manufacturing, agriculture, energy, defence, aerospace and buildings. Exploration of these potentialities around space and time would create applications which would affect societal and economic benefit. This paper looks into the concept of emerging Cyber-Physical system, applications and security issues in sustaining development in various economic sectors; outlining a set of strategic Research and Development opportunities that should be accosted, so as to allow upgraded CPS to attain their potential and provide a wide range of societal advantages in the future.

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Resource-aware Automotive Control Systems Design: A Cyber-Physical Systems Approach

10.1561/9781680832396 ◽

2016 ◽

Author(s):

Chang Wanli ◽

Chakraborty Samarjit

Keyword(s):

Control Systems ◽

Systems Approach ◽

Systems Design ◽

Cyber Physical Systems ◽

Automotive Control ◽

Physical Systems ◽

Control Systems Design ◽

Resource Aware

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Security of Cyber-Physical Systems: A Generalized Algorithm for Intrusion Detection and Determining Security Robustness of Cyber Physical Systems using Logical Truth Tables

Vanderbilt Undergraduate Research Journal ◽

10.15695/vurj.v9i0.3765 ◽

2013 ◽

Vol 9 ◽

Cited By ~ 4

Author(s):

Curtis G. Northcutt

Keyword(s):

Intrusion Detection ◽

Cyber Security ◽

Logical Truth ◽

Cyber Physical Systems ◽

Security Model ◽

Security Measures ◽

Physical Systems ◽

Multiple Signal ◽

Security Attack ◽

Truth Tables

The recent proliferation of embedded cyber components in modern physical systems [1] has generated a variety of new security risks which threaten not only cyberspace, but our physical environment as well. Whereas earlier security threats resided primarily in cyberspace, the increasing marriage of digital technology with mechanical systems in cyber-physical systems (CPS), suggests the need for more advanced generalized CPS security measures. To address this problem, in this paper we consider the first step toward an improved security model: detecting the security attack. Using logical truth tables, we have developed a generalized algorithm for intrusion detection in CPS for systems which can be defined over discrete set of valued states. Additionally, a robustness algorithm is given which determines the level of security of a discrete-valued CPS against varying combinations of multiple signal alterations. These algorithms, when coupled with encryption keys which disallow multiple signal alteration, provide for a generalized security methodology for both cyber-security and cyber-physical systems.

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