Smart Cities and Cyber Security: Are We There Yet? A Comparative Study on the Role of Standards, Third Party Risk Management and Security Ownership

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Smart cities have brought a variety of benefits aiming to revolutionise people’s lives. Those include but are not limited to, increasing economic e ciency, reducing cost and decreasing environmental output. However, the smart city itself is still in its infancy. As it heavily relies on technologies, it opens up doors to cyber attackers and criminals, which can lead to significant losses. An outstanding problem concerns the social and organisational aspects of smart cities security resulting from competing interests of di event parties, high levels of interdependence, and social and political complexity. Our review shows that current standards and guidelines have not clearly defined roles and responsibilities of di erent parties. A common understanding of key security requirements is not shared between di erent parties. This research assessed the smart cities and their cyber security measures, with a particular focus on technical standards and the regulatory framework. It comprehensively reviewed 93 security standards and guidance. It then performed a comparative case study of Barcelona, Singapore and London smart cities on their governance models, security measures, technical standards and third party management. Based on the review and the case study, this research concluded on a recommended framework encompassing technical standards, governance input, regulatory framework and compliance assurance to ensure that security is observed at all layers of the smart cities

Digital Flourishing: Conceptualizing and Assessing Positive Perceptions of Mediated Social Interactions

Recent research started to apply concepts of well-being to the context of computer mediated communication (e.g., social media, instant messaging). While much research investigates negative perceptions of mediated social interactions (e.g., “problematic” or “addictive” social media use), a multi-dimensional measure that taps into users? positive perceptions is sorely lacking. The present research therefore develops the first comprehensive measure of digital flourishing, defined as positive perceptions of mediated social interactions. Building on a qualitative pre-study that aided the construction of the Digital Flourishing Scale (DFS), Study 1 (N = 474) employed exploratory factor analysis to reveal five subdimensions of digital flourishing. The preregistered Study 2 (N = 438) confirmed these five dimensions, yielding five reliable items per subscale and initial construct validity with three psychological needs from self-determination theory (SDT; competence, autonomy, relatedness) which were used as an underlying well-being framework for the development of the DFS. The preregistered Study 3 generated further construct validity by directly relating DFS to well-being. The scale is relevant for researchers and practitioners alike to better understand how users perceive their mediated interactions to impact mental health and well-being

Universal homodyne tomography with a single local oscillator

We propose a general method for measuring an arbitrary observable of a multimode electromagnetic field using homodyne detection with a single local oscillator. In this method the local oscillator scans over all possible linear combinations of the modes. The case of two modes is analyzed in detail and the feasibility of the measurement is studied on the basis of Monte-Carlo simulations. We also provide an application of this method in tomographic testing of the GHZ state.Comment: 12 pages, 5 figures (8 eps files

Bichromatic atomic lens

We investigate the focusing of three-level atoms with a bichromatic standing wave laser field, using both classical and quantum treatments of the problem. We find that, for the appropriate ratio of detunings to Rabi frequencies, the atoms will experience a periodic potential which is close to harmonic across half an optical wavelength. The field thus becomes equivalent to a periodic array of microlenses, which could be utilized to deposit lines of atoms upon a substrate. We consider and compare two regimes, differentiated by the interaction time of the atoms in the optical field. The first case considered, the Raman-Nath regime, is analogous to the thin lens regime in classical optics. The second case treats the transverse atomic motion within the light field, and investigates the distribution of atoms upon a substrate placed within the field. We investigate the extent to which this case can be modeled classically

Talbot Oscillations and Periodic Focusing in a One-Dimensional Condensate

An exact theory for the density of a one-dimensional Bose-Einstein condensate with hard core particle interactions is developed in second quantization and applied to the scattering of the condensate by a spatially periodic impulse potential. The boson problem is mapped onto a system of free fermions obeying the Pauli exclusion principle to facilitate the calculation. The density exhibits a spatial focusing of the probability density as well as a periodic self-imaging in time, or Talbot effect. Furthermore, the transition from single particle to many body effects can be measured by observing the decay of the modulated condensate density pattern in time. The connection of these results to classical and atom optical phase gratings is made explicit

Continuous optical loading of a Bose-Einstein Condensate

The continuous pumping of atoms into a Bose-Einstein condensate via spontaneous emission from a thermal reservoir is analyzed. We consider the case of atoms with a three-level $\Lambda$ scheme, in which one of the atomic transitions has a very much shorter life-time than the other one. We found that in such scenario the photon reabsorption in dense clouds can be considered negligible. If in addition inelastic processes can be neglected, we find that optical pumping can be used to continuously load and refill Bose-Einstein condensates, i.e. provides a possible way to achieve a continuous atom laser.Comment: 12 pages, 8 figure

Least-squares inversion for density-matrix reconstruction

We propose a method for reconstruction of the density matrix from measurable time-dependent (probability) distributions of physical quantities. The applicability of the method based on least-squares inversion is - compared with other methods - very universal. It can be used to reconstruct quantum states of various systems, such as harmonic and and anharmonic oscillators including molecular vibrations in vibronic transitions and damped motion. It also enables one to take into account various specific features of experiments, such as limited sets of data and data smearing owing to limited resolution. To illustrate the method, we consider a Morse oscillator and give a comparison with other state-reconstruction methods suggested recently.Comment: 16 pages, REVTeX, 6 PS figures include

High resolution amplitude and phase gratings in atom optics

An atom-field geometry is chosen in which an atomic beam traverses a field interaction zone consisting of three fields, one having frequency $\Omega =c/\lambda$ propagating in the $\hat{z}$ direction and the other two having frequencies $\Omega +\delta_{1}$ and $\Omega +\delta_{2}$ propagating in the -$\hat{z}$ direction. For $n_{1}\delta_{1}+n_{2}\delta_{2}=0$ and $|\delta_{1}| T,|\delta_{2}| T\gg 1$, where $n_{1}$ and $n_{2}$ are positive integers and $T$ is the pulse duration in the atomic rest frame, the atom-field interaction results in the creation of atom amplitude and phase gratings having period $\lambda /[2(n_{1}+n_{2})]$. In this manner, one can use optical fields having wavelength $\lambda$ to produce atom gratings having periodicity much less than $\lambda$.Comment: 11 pages, 14 figure

Self-homodyne tomography of a twin-beam state

A self-homodyne detection scheme is proposed to perform two-mode tomography on a twin-beam state at the output of a nondegenerate optical parametric amplifier. This scheme has been devised to improve the matching between the local oscillator and the signal modes, which is the main limitation to the overall quantum efficiency in conventional homodyning. The feasibility of the measurement is analyzed on the basis of Monte-Carlo simulations, studying the effect of non-unit quantum efficiency on detection of the correlation and the total photon-number oscillations of the twin-beam state.Comment: 13 pages (two-column ReVTeX) including 21 postscript figures; to appear on Phys. Rev.

Creating a low-dimensional quantum gas using dark states in an inelastic evanescent-wave mirror

We discuss an experimental scheme to create a low-dimensional gas of ultracold atoms, based on inelastic bouncing on an evanescent-wave mirror. Close to the turning point of the mirror, the atoms are transferred into an optical dipole trap. This scheme can compress the phase-space density and can ultimately yield an optically-driven atom laser. An important issue is the suppression of photon scattering due to ``cross-talk'' between the mirror potential and the trapping potential. We propose that for alkali atoms the photon scattering rate can be suppressed by several orders of magnitude if the atoms are decoupled from the evanescent-wave light. We discuss how such dark states can be achieved by making use of circularly-polarized evanescent waves.Comment: 8 pages, 4 figure