Single Physical System Research Articles

Local model dynamics for two qubits

The density matrix model described in an earlier paper “Model Dynamics for Quantum Computing” is applied to the case of two qubits. The earlier paper provided a density matrix dynamics with unitary time-dependent gates including qubit energy splitting, entropy constraints, external bath and noise effects. The Lindblad formulation as extended by Beretta was adopted in designing this model. Visualization was provided by examining the time-evolution of the polarization vector. In this paper, the same ideas are applied to two-qubit systems, where there are now 15 time-dependent observables; namely, six polarization vectors (P→A,P→B), and nine spin-correlations (T↔). These time-dependent observables provide ready visualization of two qubit dynamics. Special emphasis is placed on the CNOT gate, which is implemented following recent outstanding developments in using silicon-based dots. By invoking a different splitting for each qubit, plus a spin–spin interaction and a carefully designed Rabi oscillation, a CNOT gate is generated. Careful analysis of the time-dependence of these aspects provides insight into CNOT dynamics. The model can be used to ascertain the sensitivity and efficacy of such a CNOT gate when subject to external environmental effects such as noise disturbances, and noise compensation, using the single-system formulation of steepest-entropy-ascent (SEA) non-equilibrium quantum thermodynamics, suitable to model controlled-gate implementations as long as the two qubits remain localized and effectively behave as a single physical four-level system. The role of careful timing in constructing an efficient CNOT gate is illustrated. The formation of Bell states and the evolution of entanglement including noise, bath and entropy considerations are examined. Extensions to the two-qubit swap, and to the three-qubit Toffoli gate dynamics are outlined. It is also shown that a simple Lindblad form can be used to introduce weak and distinct qubit noise pulses. A simple scheme for noise compensation is designed to increase purity and decrease entropy, without invocation of quantum correction methodology. It is based on using the preexisting entanglement of the environment with the quantum system and carefully designed non-Hermitian Lindblad pulses.

Building a Space for the Human in IoT: Contributions of a design process

Technological devices integrate people’s lives, actively connecting the Physical and the Digital worlds. Through ubiquitous computing, we can build a network of objects that, in addition to exchanging information, can perceive and act in a certain environment. The network of interconnected objects that is part of Human daily life can and should be called the Internet of Human Things (IoHT) as it involves re-configurations in living environments, in which objects (physical things) start to interact with each other and with people, often without human awareness. For this reason, the design of an IoT environment requires a good understanding of the problem and an evolution of ideas towards a possible solution in which People and other Physical things are linked to the Digital and can be considered as a single (Social, Physical and Digital) System. This article presents a Socially Aware Design process which evolves a solution starting from the understanding of the problem by the interested parties who act as co-designers. The process is illustrated with three workshops held with children, accompanied by their families in a hospital environment, whose objective was the evolution of an IoHT-based (Internet of Human Things) scenario. From the understanding of the design problem to the closing of the third workshop, the maturation of a design process for IoT environments with people is presented and discussed.

Unraveling the Observational Signatures of Cloud–Cloud Collision and Hub-filament Systems in W31

To understand the formation process of massive stars, we present a multiscale and multiwavelength study of the W31 complex hosting two extended H ii regions (i.e., G10.30-0.15 (hereafter, W31-N) and G10.15-0.34 (hereafter, W31-S)) powered by a cluster of O-type stars. Several Class i protostars and a total of 49 ATLASGAL 870 μm dust clumps (at d = 3.55 kpc) are found toward the H ii regions where some of the clumps are associated with the molecular outflow activity. These results confirm the existence of a single physical system hosting the early phases of star formation. The Herschel 250 μm continuum map shows the presence of a hub-filament system (HFS) toward both W31-N and W31-S. The central hubs harbor H ii regions and they are depicted with extended structures (with T d ∼ 25–32 K) in the Herschel temperature map. In the direction of W31-S, an analysis of the NANTEN2 12CO(J = 1−0) and SEDIGISM 13CO(J = 2−1) line data supports the presence of two cloud components around 8 and 16 km s−1, and their connection in velocity space. A spatial complementary distribution between the two cloud components is also investigated toward W31-S, where the signposts of star formation, including massive O-type stars, are concentrated. These findings favor the applicability of cloud–cloud collision (CCC) around ∼2 Myr ago in W31-S. Overall, our observational findings support the theoretical scenario of CCC in W31, which explains the formation of massive stars and the existence of HFSs.

Noise-robust preparation contextuality shared between any number of observers via unsharp measurements

Multiple observers who independently harvest nonclassical correlations from a single physical system share the system's ability to enable quantum correlations. We show that any number of independent observers can share the preparation contextual outcome statistics enabled by state ensembles in quantum theory. Furthermore, we show that even in the presence of any amount of white noise, there exists quantum ensembles that enable such shared preparation contextuality. The findings are experimentally realised by applying sequential unsharp measurements to an optical qubit ensemble which reveals three shared demonstrations of preparation contextuality.

Schmidt Decomposition and Coherence of Interfering Alternatives

The Schmidt decomposition and the correlational analysis based on it make it possible to identify statistical dependences between various subsystems of a single physical system. The systems under consideration can be both quantum states and classical probability distributions. In this study, two different physical systems are considered: quantum Schrödinger cat states and double-slit interference of microparticles. It is shown that the considered systems have a single internal structure and can be described in general terms of interfering alternatives. An effective approach is developed that allows us to calculate optical characteristics of interference such as visibility and coherence. It is shown that the scalar product of the states of the environment of interfering alternatives acts as a natural generalization of the classical complex parameter of the coherence of light oscillations, which determines the visibility of the interference pattern. A simple quantitative relationship is obtained between the visibility of the interference pattern and the Schmidt number, which determines the level of connection between a quantum system and its environment. The developed approaches are generalized to the case of multidimensional Schrödinger cat states.

Mitigation Of Virtual Machine (VM) Using Cloud Computing

Cloud computing enables users to move their calculations to a distributed environment, where additional resources may be used to finish execution more rapidly. Virtualization refers to the ability to run numerous virtual machines (VM) on a single physical system. VM switches one physical computer to another during the migration process. Offline migration stops the operation until the virtual machine can continue on the destination system, but live migration continues uninterrupted. Live migration is one in which the VM seems to be responding all of the time from the perspective of the clients. A virtual machine (VM) is a computer system that is emulated. Virtual machine migration is a helpful tool in cloud computing for moving Operating System instances across different physical machines. It is used to balance loads, manage faults, perform low-level system maintenance, and minimize energy usage. For VM migration, several approaches and parameters are available. The different virtual machine migration strategies are discussed in this study.

Parallel random bitstreams from a single source of entropy based on nonthermal electrochemical microplasma

AbstractThis study presents the simultaneous generation of two uncorrelated and continuous high‐quality random bitstreams originating from a single physical system based on confined, nonthermal electrochemical microplasma operating under atmospheric conditions. The randomness is intrinsically inherited from the time‐resolved electrical current and optical emission intensities of the microplasma system, which were collected using wide bandwidth current probe and photodetection device. The parallel bitstreams pass unambiguously all 15 NIST SP 800‐22 statistical tests without the need for any data post‐processing. Using the NIST SP 800‐90B package, the min‐entropy estimates of both noise sources were found to be no less than 0.994. This parallel data acquisition can be viewed as a simple strategy to increase the bit generation rate without compromising their quality or adding post‐processing routines.

Energy Efficient Resource Allocation in Cloud Computing

Cloud service provider in cloud environment will provide or provision resource based on demand from the user. The cloud service provider (CSP) will provide resources as and when required or demanded by the user for execution of the job on the cloud environment. The CSP will perform this in a static and dynamic manner. The CSP should also consider various other factors in order to provide the resources to the user, the prime among that will be the Service Level Agreement (SLA), which is normally signed by the user and cloud service provider during the inception phase of service. There are many algorithm which are used in order to allocate resources to the user in cloud environment. The algorithm which is proposed will be used to reduce the amount of energy utilized in performing various job execution in cloud environment. Here the energy utilized for execution of various jobs are taken into account by increasing the number of virtual machines that are used on a single physical host system. There is no thumb rule to calculate the number of virtual machines to be executed on a single host. The same can be derived by calculating the amount of space, speed required along with the time to execute the job on a virtual machine. Based up on this we can derive the number of Virtual machine on a single host system. There can be 10 virtual machines on a single system or even 20 number of virtual machines on single physical system. But if the same is calculated by the equation then the result will be exactly matching with the threshold capacity of the physical system[1]. If more number of physical systems are used to execute fewer virtual machines on each then the amount of energy consumed will be very high. So in order to reduce the energy consumption , the algorithm can be used will not only will help to calculate the number of virtual machines on single physical system , but also will help to reduce the energy as less number of physical systems will be in need[2].

Modelling critical infrastructure network interdependencies and failure

Critical infrastructures are fundamental systems that are interconnected with one another, and their interdependencies need to be modelled in order to analyse any vulnerabilities that exist in these infrastructure networks. In this work, a Leontief input-output model of the critical infrastructure systems and two physical critical infrastructure networks are developed. The input-output model serves to evaluate the interdependencies among the various infrastructure systems, while the physical infrastructure network describes the linkages within a single physical infrastructure system. This study examines the overall impact of any failures in the telecommunication infrastructure or electricity grid within the input-output interdependencies model systematically so as to evaluate the worst case scenarios based on the impact caused by one or more points of failure in the physical infrastructure.

Modelling critical infrastructure network interdependencies and failure

Critical infrastructures are fundamental systems that are interconnected with one another, and their interdependencies need to be modelled in order to analyse any vulnerabilities that exist in these infrastructure networks. In this work, a Leontief input-output model of the critical infrastructure systems and two physical critical infrastructure networks are developed. The input-output model serves to evaluate the interdependencies among the various infrastructure systems, while the physical infrastructure network describes the linkages within a single physical infrastructure system. This study examines the overall impact of any failures in the telecommunication infrastructure or electricity grid within the input-output interdependencies model systematically so as to evaluate the worst case scenarios based on the impact caused by one or more points of failure in the physical infrastructure.

Experimental Cyclic Interconversion between Coherence and Quantum Correlations.

Quantum resource theories seek to quantify sources of nonclassicality that bestow quantum technologies their operational advantage. Chief among these are studies of quantum correlations and quantum coherence. The former isolates nonclassicality in the correlations between systems, and the latter captures nonclassicality of quantum superpositions within a single physical system. Here, we present a scheme that cyclically interconverts between these resources without loss. The first stage converts coherence present in an input system into correlations with an ancilla. The second stage harnesses these correlations to restore coherence on the input system by measurement of the ancilla. We experimentally demonstrate this interconversion process using linear optics. Our experiment highlights the connection between nonclassicality of correlations and nonclassicality within local quantum systems and provides potential flexibilities in exploiting one resource to perform tasks normally associated with the other.

Improving the accuracy of granular sludge and biofilm reactor simulations in Aquasim through artificial diffusion.

Aquasim is public-domain and user-friendly software that is widely used for biofilm modeling. The program uses built-in process unit blocks, such as biofilm and mixed compartments. In the literature, often several of these compartments are linked with artificial advective flows to represent a single physical well-mixed system, such as a granular sludge reactor. This work shows that caution should be exercised with this popular approach because numerical errors occur when too high artificial advective flows are used. These errors could stay unnoticed if mass-balances of the simulation results are not checked. A solution to this problem is proposed in this work. A new method based on diffusive links between compartments instead of advective links leads to more reliable and faster simulations and is much easier to implement. Biotechnol. Bioeng. 2017;114: 2131-2136. © 2017 Wiley Periodicals, Inc.

Information content of systems as a physical principle

To explain conceptual gap between classical/quantum and other, hypothetical descriptions of world, several principles has been proposed. So far, all these principles have not explicitly included the uncertainty relation. Here we introduce an information content principle (ICP) which represents the new - constrained uncertainty principle. The principle, by taking into account the encoding/decoding properties of single physical system, is capable of separation both classicality and quanta from a number of potential physical theories including hidden variable theories. The ICP, which is satisfied by both classical and quantum theory, states that the amount of non-redundant information which may be extracted from a given system is bounded by a perfectly decodable information content of the system. We show that ICP allows to discriminate theories which do not allow for correlations stronger than Tsirelson's bound. We show also how to apply the principle to composite systems, ruling out some theories despite their elementary constituents behave quantumly.

Full Stark control of polariton states on a spin-orbit hypersphere

The orbital angular momentum and the polarisation of light are physical quantities widely investigated for classical and quantum information processing. In this work we propose to take advantage of strong light-matter coupling, circular-symmetric confinement, and transverse-electric transverse-magnetic splitting to exploit states where these two degrees of freedom are combined. To this end we develop a model based on a spin-orbit Poincar\'{e} hypersphere. Then we consider the example of semiconductor polariton systems and demonstrate full ultrafast Stark control of spin-orbit states. Moreover, by controlling states on three different spin-orbit spheres and switching from one sphere to another we demonstrate the control of different logic bits within one single physical system.

ACCRS: autonomic based cloud computing resource scaling

A cloud computing model gives cloud service providers the ability to retain multiple workloads on a single physical system. However, efficient resource provisioning and possible system fault management in the cloud can be a challenge. Early fault detection can provide room to recover from potential faults before impacting QoS. Current static techniques of fault management in computing systems are not satisfactory enough to safeguard the QoS requested by cloud users. Thus, new smart techniques are needed. This paper presents the ACCRS framework for cloud computing infrastructures to advance system’s utilization level, reduce cost and power consumption and fulfil SLAs. The ACCRS framework employs Autonomic Computing basic components which includes state monitoring, planning, decision making, fault predication, detection, and root cause analysis for recovery actions to improve system’s reliability, availability, and utilization level by scaling resources in response to changes in the cloud system state.

Counting steps: a finitist approach to objective probability in physics

We propose a new interpretation of objective probability in statistical physics based on physical computational complexity. This notion applies to a single physical system (be it an experimental set-up in the lab, or a subsystem of the universe), and quantifies (1) the difficulty to realize a physical state given another, (2) the ‘distance’ (in terms of physical resources) between a physical state and another, and (3) the size of the set of time-complexity functions that are compatible with the physical resources required to reach a physical state from another. This view (a) exorcises ‘ignorance’ from statistical physics, and (b) underlies a new interpretation to non-relativistic quantum mechanics.

Effect of Virtualization on Enterprise Network, Server/Desktop Systems on Small and Mid-Size Businesses (SMB)

INTRODUCTION Enterprise network infrastructure has profoundly impacted information systems business world. As small, mid-size businesses, various devices and data move beyond the traditional security of the corporate landscape, cyber-attacks will continue to grow at an exponential proportion. In 2012, network security gurus experienced cyber dangers ranging from sophisticated advanced persistent threats, to firewire attacks, to lost or stolen laptop. Enterprise network's mobile endpoints are literally moving targets and until they are adequately secured against attacks, enterprise business intelligence, reputation or competitiveness are at risk The goal of this article included the following: 1. To identify the extent mid- size organizations have adopted or planned to adopt virtualization technology 2012. 2. Identify potential barriers that cause enterprise systems to postpone or decide not to adopt virtualization. 3. Identify among adopting firms, what virtualization products are most popular and which applications are most commonly virtualized? 4. Identify the core drivers that cause enterprise systems to be virtualized. LITERATURE REVIEW Berde et al. (2009) among others noted that virtualization is not a perfect solution to how organizations manage their resources but concluded that this technology provides tremendous capabilities on how enterprise systems manage and move operating systems into different hardware resources. Grid computing evolved as an innovative technology, and is distinguished from traditional distributed networks because of its large-scale resource sharing capabilities. The author further explained that grid computing allows large numbers of hardware components to act as a single device, thereby, pooling their capacity and re-allocating these components to different jobs. Ercan (2010) argued that in the next generation of Grids, applications will not necessarily be designed to run on certain piece of hardware or network, but will be written to consume certain types of resources, which could be provided anywhere on the network. He further summarized that to accomplish this, enterprise systems and technical gurus need more dynamic networks than are at the present time existence. However, noted that virtualization efforts the networking community are already moving the industry that direction. Fiedler and Gallenkamp (2008), their study reviled that virtualized infrastructure provides a layer of abstraction between computing storage, networking hardware, and the applications running on it. Their study further explained that the deployment of virtual infrastructure is nondisruptive to the system, because the user experiences are typically un-noticed or unchanged. The authors concludes by emphasizing that virtual infrastructure provide enterprise system management, the opportunity to manage pooled resources across the enterprise, thereby, allowing Information Technology (IT) managers to be more responsive to dynamic system needs to better leverage infrastructure investments. Early studies by Burry et al. (2004), Brandel (2004), Cannor (2005), found evidence that virtualization has been a part of the IT landscape for decades but today vendors are now conveying remuneration to industry-standard X86-based platforms which now encompass the preponderance of desktops, laptops and server shipments. They concluded by stating that a major benefit of virtualization is the ability of systems to run multiple operating systems on a single physical system while sharing the underlying hardware resources or partitioning. More recent studies have concluded that virtualization can apply to a range of system layers, including hardware-level virtualization, operating system- level virtualization, and high-level language virtual machines (Morana et al., 2011; Seyler et al., 2011; Tusa & Mikkilinemi, 2011) . …

Scheduler vulnerabilities and coordinated attacks in cloud computing

In hardware virtualization a hypervisor provides multiple Virtual Machines VMs on a single physical system, each executing a separate operating system instance. The hypervisor schedules execution of these VMs much as the scheduler in an operating system does, balancing factors such as fairness and I/O performance. As in an operating system, the scheduler may be vulnerable to malicious behavior on the part of users seeking to deny service to others or maximize their own resource usage.Recently, publically available cloud computing services such as Amazon EC2 have used virtualization to provide customers with virtual machines running on the provider's hardware, typically charging by wall clock time rather than resources consumed. Under this business model, manipulation of the scheduler may allow theft of service at the expense of other customers, rather than merely re-allocating resources within the same administrative domain.We describe a flaw in the Xen scheduler allowing virtual machines to consume almost all CPU time, in preference to other users, and demonstrate kernel-based and user-space versions of the attack. We show results demonstrating the vulnerability in the lab, consuming as much as 98% of CPU time regardless of fair share, as well as on Amazon EC2, where Xen modifications protect other users but still allow theft of service following the responsible disclosure model, we have reported this vulnerability to Amazon; they have since implemented a fix that we have tested and verified. We provide a novel analysis of the necessary conditions for such attacks, and describe scheduler modifications to eliminate the vulnerability. We present experimental results demonstrating the effectiveness of these defenses while imposing negligible overhead.Also, cloud providers such as Amazon's EC2 do not explicitly reveal the mapping of virtual machines to physical hosts [in: ACM CCS, 2009]. Our attack itself provides a mechanism for detecting the co-placement of VMs, which in conjunction with appropriate algorithms can be utilized to reveal this mapping. Other cloud computing attacks may use this mapping algorithm to detect the placement of victims.

Scheduler vulnerabilities and coordinated attacks in cloud computing

In hardware virtualization a hypervisor provides multiple Virtual Machines VMs on a single physical system, each executing a separate operating system instance. The hypervisor schedules execution o...

A Novel Framework for Virtual Desktop Environment with vApp

technology is transforming today's IT community, offering new possibilities to improve the performance and efficiency of IT infrastructure by a dynamic mapping of the PC resources, enabling to run several applications and operating systems on a single physical system. Virtualization also offers elevated ease of use and error recovery solutions by encapsulating entire systems into single files that can be replicated and restored on any destination machine. This paper brings new elements related to the concept of virtualization, presenting the principles, the new architectures and the advantages of the virtualization. A new framework has drawn for using different types of operating system(OS) with a vApp in a single operating system. Creating the vApp's in VMware Studio and using the vApp anywhere any time. KeywordsvApp, VMware Studio, Operating System (OS).