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Tsokos-Pappas A.,Freelancer | Giftopoulos S.,National Technical University of Athens | Mazarakos T.,Technological Educational Institute of Athens
18th International Conference on Ships and Shipping Research, NAV 2015 | Year: 2015

The objective of this paper is to research ship design under the scope of the educational background provided by a school of architecture. The means by which we attempt to approach this aspect of ship design is the scenario of the rebuilding and retrofitting of an already existent ro-pax ferry into a small hospital ship intended to serve the island complex of the Aegean Sea. Such a concept ensures on the one hand that the general dimensions and mechanical characteristics of such ship would enable it to approach, moor and perform even at the smallest of harbors, and on the other hand that the extent of the structural rebuilding would enable to express the intended architectural qualities. Regarding to these, and according to the established building program, particular attention is given to the proper location and design of required spaces, taking into account a number of design provisions considered in order to ensure a high standard of living, working and medical care within the ship. Finally, the study contains fire safety and lifesaving device plans, aiming at a wider and more comprehensive approach to the design of a vessel as functional hospital ship. © 2015 Organising Committee NAV 2015.


Madjdi F.,Freelancer | Husig S.,University of Regensburg
Telecommunications Policy | Year: 2011

This paper examines how three incumbent mobile network operators (MNOs) in Germany responded in terms of their strategy to the emergence of the wireless local area network (W-LAN) technology and how they interpreted this potentially disruptive technology in their own strategic context. Additionally, prior empirical results and forecasts on the limited disruptive potential of W-LAN for the German MNOs lacked persuasive firm-level evidence to distinguish the real reason for the presented observations and analysis. So far it was unclear whether the observations were caused by successful response strategies of incumbent MNOs or by the inherent limited disruptive potential of the W-LAN technology. For this purpose case studies of three major MNOs in Germany were performed to assess and compare their respective response strategies. Using the theoretical framework of disruptive technology, the results were evaluated in a cross-case analysis to study how these firms interpreted and reacted to the potential disruptiveness of W-LAN. The results indicate significant differences for the respective MNOs between their perception of W-LAN as a potential disruptive technology, their strategic development processes inside the organisation to understand the potential impact of W-LAN on their respective business model, and to enforce an appropriate response strategy and structural implementation. This incumbent heterogeneity depends primarily on their idiosyncratic strategic and structural context. These findings reveal that the incumbent MNOs in Germany were aware of the disruptive technology concept but did not react in a theory-conform way. However, since W-LAN had a sustaining impact on the MNOs and their response strategies followed sustaining reaction patterns, earlier studies, which show a limited disruptive potential of W-LAN for the German MNOs, are supported. © 2011 Elsevier Ltd. All rights reserved.


Bijalwan N.,FreeLancer
Astrophysics and Space Science | Year: 2012

We show in this article that charged fluid with pressure derived by Bijalwan (Astrophys. Space. Sci. doi:10. 1007/s10509-011-0691-0, 2011a) can be used to model classical electron, quark, neutron stars and pulsar with charge matter, quasi black hole, white dwarf, super-dense star etc. Recent analysis by Bijalwan (Astrophys. Space. Sci., 2011d) that all charged fluid solutions in terms of pressure mimic the classical electron model are partially correct because solutions by Bijalwan (Astrophys. Space. Sci. doi:10. 1007/s10509-011-0691-0, 2011a) may possess a neutral counterpart. In this paper we characterized solutions in terms of pressure for charged fluids that have and do not have a well behaved neutral counter part considering same spatial component of metric e λ for neutral and charged fluids. We discussed solution by Gupta and Maurya (Astrophys. Space Sci. 331(1):135-144, 2010a) and solutions by Bijalwan (Astrophys. Space Sci. doi:10. 1007/s10509-011-0735-5, 2011b; Astrophys. Space Sci. doi:10. 1007/s10509-011-0780-0, 2011c; Astrophys. Space Sci., 2011d) such that charged fluids possess and do not possess a neutral counterpart as special cases, respectively. For brevity, we only present some analytical results in this paper. © 2011 Springer Science+Business Media B.V.


Bijalwan N.,FreeLancer | Gupta Y.K.,Indian Institute of Technology Roorkee
Astrophysics and Space Science | Year: 2012

In the present article models of well behaved charged superdense stars with surface density 2×10 14 gm/cm 3 are constructed by considering a static spherically symmetric metric with t = const hypersurfaces as spheroids and hyperboloids. Maximum mass of the star is found to be 7. 66300M Θ with radius 19. 35409 km for spheroids case while 1. 51360M Θ with radius 13. 72109 km for hyperboloid case satisfying ultra-relativistic conditions. The solutions thus found satisfy all the reality and causality conditions. For brevity we don't present a detailed analysis of the derived solutions in this paper. © 2011 Springer Science+Business Media B.V.


Bijalwan N.,FreeLancer
International Journal of Theoretical Physics | Year: 2012

General exact higher-dimensional (n+2), n > 2 solutions in general theory of relativity of Einstein-Maxwell field equations for spherically symmetric distribution of charged pressure perfect fluid are expressed in terms of pressure extending 4-dimensional solutions presented by Bijalwan (Astrophys. Space Sci. 2011, doi:10.1007/s10509-011-0691-0). Subsequently, metrics (eλ and eυ), matter density and electric intensity are expressible in terms of pressure. Consequently, Pressure is found to be an invertible arbitrary function of ω (=c1+c2r2), where c1 and c2 (≠0) are arbitrary constants, and r is the radius of star, i. e. p=p(ω). We present a general solution for charged pressure fluid in terms for ω. We list and discuss some old and new solutions which fall in this category. Also, these solutions satisfy barotropic equation of state relating the radial pressure to the energy density. But we noticed that none of these solutions in terms of pressure for charged fluids has a well behaved neutral counter part for a spatial component of metric eλ i. e. choosing same spatial component for charged and neutral fluid. To illustrate the approach, we discovered a new solution for extended charged analogues of Schwarzschild interior solution in higher dimensions which is found to be well behaved only for n=2. The maximum mass found to be 1. 512 MΘ with linear dimension 14. 964 km. Physical quantities pressure, energy density, red-shift, velocity of sound and p/c2ρ are well behaved and monotonically decreasing towards the surface while adiabatic index and charge density are monotonically increasing. For brevity we don't discuss the numerical results in detailed. © 2011 Springer Science+Business Media, LLC.


Kawano Y.,Tokyo University of Information Sciences | Obu Y.,Freelancer
Proceedings - 2014 International Conference on Network-Based Information Systems, NBiS 2014 | Year: 2014

Social media such as Twitter and Facebook have become popular. In the age of social media, many people have become more active online. Personal branding is a very important strategy for capitalizing on individual strong points. This kind of branding is expected to contribute to self-actualization. Therefore, the presence of mentors who advise users to find their strong points for self-actualization is needed. We have proposed a personal branding support service named Mentors. In this paper, we propose a reconstruction of self-actualization support service based on the 7 habits. Concretely, Mentors is divided into two parts, that is, Self-reflector and Socializer. Self-reflector aims at inside branding that focuses on private victory. Socializer aims at outside branding that focuses on public victory. © 2014 IEEE.


Bijalwan N.,FreeLancer
Astrophysics and Space Science | Year: 2011

Recently, Bijalwan (Astrophys. Space Sci., doi: 10.1007/s10509-011-0691-0, 2011a) discussed charged fluid spheres with pressure while Bijalwan and Gupta (Astrophys. Space Sci. 317, 251-260, 2008) suggested using a monotonically decreasing function f{hook} to generate all possible physically viable charged analogues of Schwarzschild interior solutions analytically. They discussed some previously known and new solutions for Schwarzschild parameter, a being radius of star. In this paper we investigate wide range of u by generating a class of solutions that are well behaved and suitable for modeling Neutron star charge matter. We have exploited the range u≤0.142 by considering pressure p=p(ω) and, where to explore new class of solutions. Hence, class of charged analogues of Schwarzschild interior is found for barotropic equation of state relating the radial pressure to the energy density. The analytical models thus found are well behaved with surface red shift zs≤0. 181, central red shift zc≤0.282, mass to radius ratio M/a≤0.149, total charge to total mass ratio e/M≤0.807 and satisfy Andreasson's (Commun. Math. Phys. 288, 715-730, 2009) stability condition. Red-shift, velocity of sound and p/c2ρ are monotonically decreasing towards the surface while adiabatic index is monotonically increasing. The maximum mass found to be 1.512 MΘ with linear dimension 14.964 km. Class of charged analogues of Schwarzschild interior discussed in this paper doesn't have neutral counter part. These solutions completely describe interior of a stable Neutron star charge matter since at centre the charge distribution is zero, e/M≤0.807 and a typical neutral Neutron star has mass between 1.35 and about 2.1 solar mass, with a corresponding radius of about 12 km (Kiziltan et al., arXiv:1011.4291 [astro-ph. GA], 2010). © 2011 Springer Science+Business Media B.V.


Bijalwan N.,FreeLancer | Gupta Y.K.,Indian Institute of Technology Roorkee
Astrophysics and Space Science | Year: 2011

Recently, Bijalwan (Astrophys. Space Sci. doi:10.1007/s10509-011-0691-0, 2011) discussed all important solutions of charged fluid spheres with pressure and Gupta et al. (Astrophys. Space Sci. doi:10.1007/s10509-010-0561-1,2010) found first closed form solutions of charged Vaidya-Tikekar (V-T) type super-dense star. We extend here the approach evolved by Bijalwan (Astrophys. Space Sci. doi:10.1007/s10509-011-0691-0, 2011) to find all possible closed form solutions of V-T type super-dense stars. The existing solutions of Vaidya-Tikekar type charged fluid spheres considering particular form of electric field intensity are being used to model massive stars. Infact at present maximum masses of the star models are found to be 8. 223931MΘ and 8. 460857MΘ subject to ultra-relativistic and non-relativistic conditions respectively. But these stars with such are large masses are not well behaved due to decreasing velocity of sound in the interior of star. We present new results concerning the existence of static, electrically charged perfect fluid spheres that have a regular interior. It is observed that electric intensity used in this article can be used to model superdense stars with ultrahigh surface density of the order 2×1014 gm/cm3 which may have maximum mass 7. 26368240MΘ for ultra-relativistic condition and velocity of sound found to be decreasing towards pressure free interface. We solve the Einstein-Maxwell equations considering a general barotropic equation of state with pressure. For brevity we don't present a detailed analysis of the derived solutions in this paper. © 2011 Springer Science+Business Media B.V.


Bijalwan N.,FreeLancer
Astrophysics and Space Science | Year: 2011

A most general exact solution to the Einstein-Maxwell equations for static charged perfect fluid is sought in terms of pressure. Subsequently, metrics (eλ and eυ), matter density and electric intensity are expressible in terms of pressure. Consequently, Pressure is found to be an invertible arbitrary function of ω(=c1+c2r2), where c1 and c2(≠0) are arbitrary constants, and r is the radius of star, i. e. p=p(ω). We present a general solution for charged pressure fluid in terms for ω. We list and discuss some old and new solutions which fall in this category. © 2011 Springer Science+Business Media B.V.


Dafner E.V.,Freelancer
International Journal of Environmental Analytical Chemistry | Year: 2016

To better understand the cycling of marine dissolved organic matter, analytical methods are required allowing for data on dissolved organic nitrogen and phosphorus (DON and DOP) to be acquired with high analytical performance. The coverage of documented DON and DOP analytical performance is very limited; instead analytical data are mostly available for total dissolved N and P (TDN and TDP) analyses. This substitution overestimates analytical performance for DON and DOP measurements due to the cumulative effect of Standard Deviation applied for detection limit and precision evaluations. The little available data obtained by photolytic, chemical, a combination of both, and high temperature combustion methods indicate that current detection limit is 0.30 µM for DON and 0.010 µM for DOP. Precision for both analytes, in general, is ≤4.5%. The data on accuracy is scarce despite availability of Reference Materials for TDN and NO3 − + NO2 − analyses, and for the TDN measurement is <5%; even fewer data exist for TDP due to a lack of reference material for this analysis. The Beer–Lambert law is linear up to 200 µM for TDN and 5–6 µM for TDP. Current analytical abilities for DON/DOP measurements are not ready yet to set the level of dissolved organic carbon analysis. The advance in the analytical performance for DON and DOP measurements depends upon the possibility to improve the analytical performance for dissolved inorganic N and P measurements involved in DON and DOP estimations. For the DOP analysis, an international standard method becomes necessary to develop and evaluate collaboratively. The chemical oceanographers’ community should reconsider requirements needed for the coverage of analytical performance for DON and DOP measurements to make this data more shareable and transparent. The lack of these data protracts marine analysts from attaining further methods improvement and development. © 2016 Informa UK Limited, trading as Taylor & Francis Group.

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