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Публікація Cyber Physical Social Systems – Future of Ukraine(EWDTS, 2014) Hahanov, V.; Gharibi, W.; Kudin, A. P.; Hahanov, I.; Ngene, C.; Yeve, T.; Krulevska, D.; Yerchenko, A.; Mishchenko, A.; Shcherbin, D.; Priymak, A.A fundamental solution of topical problem for economic, social and technological future of Ukraine and the world is proposed. The problem lies in the elimination of corruption through the formation and implementation of the state program «Creation of Cyber Physical Space for Digital Monitoring Technological Processes and Optimal Resource Management in order to Achieve Socially Important Goals». The cyber technology for human-free managing social resources (staff and finance) includes two cloud service: 1) the distribution of government contracts and finance between the structures, undertakings and entities, based on competition of their competence matrices for a given metric; 2) allocation of staff vacancies in scalable social groups based on competition of the competence matrices of applicants for a given metric. The competence metric is a measuring method of the distance between objects or processes based on the use of the parameter vector that defines the space or a competence matrix of a person or social group in real time. A competence matrix is a model of integrated activity and skills of a person or social group at a given metric and time interval. As an alternative solution of the problem it is considered a cyber physical system for managing human and financial resources (Cyber Social Systems - CSS), as a scalable cloud service, available to the social groups, government agencies, private companies and private individuals; it provides lifelong monitoring competencies of corresponding subjects in real time in order to carry out cyber staff management through appropriate career, moral and material incentives according to the results of their constructive activity. The cyber social system is focused on the total destruction of the corruption in the actions of managers at all levels by eliminating the subjectivity in the management of human and financial resources on the basis of the transfer of the official functions to independent cloud cyber service. The system consists of two interacting components: 1) accumulative monitoring of all kinds of human (social group) activity that generates a competence matrix in realtime; 2) the optimal management through career, moral and material incentives of individuals and social formations based on the analysis and rating of the corresponding competence matrices. A cyber system is based on the use of the following technologies: Big Data, Internet of Things, Smart Everything, parallel virtual processors and focused on serving individuals, government agencies and companies. For each subject two unique metrics of competencies are generated: 1) the gold standard of indexes for each category of professional activity; 2) the current competence matrix of the subjects filled in the process of their life, which are ranked by metrical comparison or evaluation of the results of work with standard or better values.Публікація Design and Optimization of a Planar UWB Antenna(EWDTS, 2013) Lim, Eng Gee; Wang, Zhao; Juans, Gerry; Man, Ka Lok; Zhang, Nan; Hahanov, V. I.; Litvinova, E. I.; Chumachenko, S. V.; Mishchenko, A.; Dementiev, S.In this paper, we present our design on a simple, low-profile wideband planar antenna with a pure circular radiator fed by a 50 Ω microstrip line. By investigating the feeding position and ground plane dimensions, the antenna is optimized to have a very wide bandwidth that covers the whole FCC-allocated ultra-wideband (UWB) spectrum. Because of the additional patch beneath the radiator, the bandwidth can be further extended towards the lower side of the frequency spectrum. This antenna is finally modified to have a bandwidth from 2 to 12 GHz, which satisfies system requirements for S-DMB, WiBro, WLAN, CMMB and the entire UWB with S11 < -10dB. Since the Federal Communications Commission (FCC) of United States allocated the unlicensed frequency spectrum from 3.1 GHz to 10.6 GHz for commercial applications of ultra-wideband (UWB) technology in 2002 [1], ultra-wideband (UWB) technology has gained great popularity in research and industrial areas because of its high data rate wireless communication capability for various applications. As a crucial part of the UWB system, UWB antennas have been investigated extensively by researchers and numerous proposals for UWB antenna designs have been reported [2-5]. In [2], a new ultra-wideband antenna consisting of two steps, a single slotted patch and a partial ground plane is designed to operate from 3.2 to 12 GHz. In J. N. Lee’s work [3], an ultrawideband antenna composed of a modified trapezoidal radiating patch, a PI-shaped matching stub, CPW feeding, and two steps for impedance matching has been proposed for UWB applications. In [4], an ultrawideband microstrip-fed monopole antenna with a narrow slit and a modified inverted U-slot on the patch is presented. Recently, a small planar antenna fed by a microstrip line has been investigated and designed to exhibit dualband operation for Bluetooth (2.4 - 2.484 GHz) and UWB (3.1 - 10.6 GHz) bands [5]. However, many of the proposed designs employed slots or other complicated modifications in the antenna radiator and/or ground plane. These designs may pose complications during fabrication of the antenna since the tolerance of the increased special features/variables could be problematic when it goes to mass production, and instability due to the fact that complicated antenna structures may also occur in practice. Therefore, we are motivated to design a low complexity, low cost and compact antenna with wide frequency coverage supporting various applications such as Satellite Digital Multimedia Broadcasting (S-DMB), Wireless Broadband (WiBro), Wireless Local Area Network (WLAN), China Multimedia Mobile Broadcasting (CMMB) and UWB. In this paper, we present a very simple circular planar antenna with operating bandwidth ranging from 2 GHz to 12 GHz by integrating several techniques into one compact antenna. The design approach is very similar to our previously reported paper [6]. We start with a simple circular planar antenna fed by a 50Ω microstrip line with a truncated ground plane. Next, based on the study of the size of the radiator and current distribution, the antenna is designed to have an operating bandwidth covering the entire UWB band, i.e. 3.1 - 10.6 GHz. Then, the study on the size of the partial ground plane is conducted to increase the bandwidth towards the lower side of the frequency spectrum, to cover the bands for WLAN (2.4 - 2.484 GHz) and CMMB (2.635 – 2.66 GHz). With an extra patch printed on the back side of the substrate, underneath the circular radiator, the bandwidth can be further increased to cover Wibro (2.3 - 2.4 GHz) and S-DBM (2.17 -2.2 GHz) without significantly influencing other frequency bands. Thus the proposed antenna can be used for various applications such as SDMB, Wibro, WLAN, CMMB and the operating bands are evaluated using with the criterion of having return loss S11 less than 10 dB. Simulated radiation patterns over the whole frequency bands are acceptable.