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We demonstrate a high dynamic range Josephson parametric amplifier (JPA) in which the active nonlinear element is implemented using an array of rf-SQUIDs. The device is matched to the 50 $\Omega$ environment with a Klopfenstein-taper impedance transformer and achieves a bandwidth of 250-300 MHz, with input saturation powers up to -95 dBm at 20 dB gain. A 54-qubit Sycamore processor was used to benchmark these devices, providing a calibration for readout power, an estimate of amplifier added noise, and a platform for comparison against standard impedance matched parametric amplifiers with a single dc-SQUID. We find that the high power rf-SQUID array design has no adverse effect on system noise, readout fidelity, or qubit dephasing, and we estimate an upper bound on amplifier added noise at 1.6 times the quantum limit. Lastly, amplifiers with this design show no degradation in readout fidelity due to gain compression, which can occur in multi-tone multiplexed readout with traditional JPAs., Comment: 10 pages, 10 figures

Inherent symmetry of a quantum system may protect its otherwise fragile states. Leveraging such protection requires testing its robustness against uncontrolled environmental interactions. Using 47 superconducting qubits, we implement the one-dimensional kicked Ising model, which exhibits nonlocal Majorana edge modes (MEMs) with ℤ 2 parity symmetry. We find that any multiqubit Pauli operator overlapping with the MEMs exhibits a uniform late-time decay rate comparable to single-qubit relaxation rates, irrespective of its size or composition. This characteristic allows us to accurately reconstruct the exponentially localized spatial profiles of the MEMs. Furthermore, the MEMs are found to be resilient against certain symmetry-breaking noise owing to a prethermalization mechanism. Our work elucidates the complex interplay between noise and symmetry-protected edge modes in a solid-state environment.

An important measure of the development of quantum computing platforms has been the simulation of increasingly complex physical systems. Prior to fault-tolerant quantum computing, robust error mitigation strategies are necessary to continue this growth. Here, we study physical simulation within the seniority-zero electron pairing subspace, which affords both a computational stepping stone to a fully correlated model, and an opportunity to validate recently introduced ``purification-based'' error-mitigation strategies. We compare the performance of error mitigation based on doubling quantum resources in time (echo verification) or in space (virtual distillation), on up to $20$ qubits of a superconducting qubit quantum processor. We observe a reduction of error by one to two orders of magnitude below less sophisticated techniques (e.g. post-selection); the gain from error mitigation is seen to increase with the system size. Employing these error mitigation strategies enables the implementation of the largest variational algorithm for a correlated chemistry system to-date. Extrapolating performance from these results allows us to estimate minimum requirements for a beyond-classical simulation of electronic structure. We find that, despite the impressive gains from purification-based error mitigation, significant hardware improvements will be required for classically intractable variational chemistry simulations., Comment: 10 pages, 13 page supplementary material, 12 figures. Experimental data available at https://doi.org/10.5281/zenodo.7225821

The discovery of topological order has revolutionized the understanding of quantum matter in modern physics and provided the theoretical foundation for many quantum error correcting codes. Realizing topologically ordered states has proven to be extremely challenging in both condensed matter and synthetic quantum systems. Here, we prepare the ground state of the toric code Hamiltonian using an efficient quantum circuit on a superconducting quantum processor. We measure a topological entanglement entropy near the expected value of $\ln2$, and simulate anyon interferometry to extract the braiding statistics of the emergent excitations. Furthermore, we investigate key aspects of the surface code, including logical state injection and the decay of the non-local order parameter. Our results demonstrate the potential for quantum processors to provide key insights into topological quantum matter and quantum error correction., Comment: 6 pages 4 figures, plus supplementary materials

The intervention of noise into images during data acquisition and transmission is inevitable. Hence, the denoising of such affected images is essential in order to have effective image analysis where it needs image filtering. The Gabor filter is widely adapted in various image processing applications for feature extraction, texture analysis, pattern analysis, etc. The Gabor-based filtering technique adopted in work is aimed for image filtering in order to extract edges. The design of a low-power portable system deploys hardware accelerators to achieve high performance per watt in feature extraction and edge detection. In this paper, an image denoising hardware accelerator model is mapped from the Gabor filter function. Moreover, hardware models for realizing various parameters involved in the Gabor function are also presented. A MATLAB model for the proposed denoising hardware accelerator is simulated and performance is measured in terms of the peak-signal-to-noise ratio, mean square error, histograms and compared with algorithm level performance reported in the literature. It is observed that the proposed hardware architecture model showed better performance compared to the mathematical models reported in the literature. However, the key limitation is the degradation of hardware performance due to a truncation or rounding of the sample’s word length.

Piping systems having service temperatures lower than ambient present a challenge for the pipe support design. Pipe supports for these cold piping systems are different from normal type of supports on pipes with service temperatures above ambient. Normally hot insulated piping systems have shoe type of supports directly welded to the pipe. In this case there is no relative movement between pipe support i.e. shoe and pipe while the pipe displaces due to changes in fluid service temperature inside the pipe. As the pipe expands when temperatures rise inside pipe, it displaces from its mean position of structural support. The shoe having been welded to pipe moves along with the pipe. On the other hand, shoe type supports on cold service pipes are not directly and permanently connected to pipe. This is due to the fact that the pipe insulation on cold service piping is designed to be seal tight so that outside air cannot get inside the insulation and reach pipe surface where it starts condensation. The condensation in turn causes corrosion issues. To avoid this moist air ingress inside the insulation, the shoes are made of clamp types and are placed outside the insulation cladding. This causes problem of clamp type shoe slippage on cladding and total displacement of pipe shoe from its structural support. This paper presents an engineering study of a piping system with cold fluid service (propane) where multiple supports had fallen from the structural supports or had dislocated considerably. At few support locations, cladding was found to be damaged and ice formation was noticed. In addition, many clamped shoes had rotated as shown in figure 1. The solution as outcome of study was simple, economical and easy to implement. A comprehensive study was conducted to identify the root cause of piping supports dislocation, displacement and rotation. The static/dynamic stress analysis of the piping system was carried out. The results revealed that the displacements in the piping system were not so high to cause the supports dislocation or high displacements of shoes. In addition, the stresses on the piping system due to the contraction of pipe upon cooling were within allowable limits. Figure 1Rotated and dislocated Clamp support on Cold Service Pipes As a part of study process, operation was enquired if any upset had happened which might have caused the dislocation and abnormal movement of pipe and hence transferred to its supports. Operations informed that there was no such incident and the line had been operating normally without any trouble. The process study including review of hydraulics, verification of line size and surge was performed to identify the root cause of piping abnormal movement. The process study concluded that line size was adequate and no surge scenario was identified for the line's concerned portion. So following reasons which could cause abnormal pipe movements and dislocation of supports were ruled out based on above study: Operation upset in the piping system (such as sudden opening or closing of a valve or sudden starting/stopping of a pump),Line sizing or surge flow,Contraction of line due to cooling of piping system or piping configuration. The next step in the study was to review the support configuration in detail. Study found basic design problem with the support configuration that was the cause of supports dislocation, excessive movement and rotation of clamped supports.

Piping systems under multi-phase flow are subjected to unbalanced forces during plant operation and they experience vibration. Usually, the piping vibrations can be minimized by either modifying piping configuration/supports or alteration of operational modes. This paper presents an engineering study of a challenging piping vibration problem, which was resolved by an inventive and cost optimizing solution, as there are limitations in modification of existing pipe support/configuration. The inventive resolution reduced implementation cost to the Company without impacting the operations. A comprehensive study was conducted to identify the root cause of piping vibration in rich amine piping system (36" pipe) from heat exchanger to amine regenerator, a tall column. The vibration screening and likelihood-of-failure calculations were carried out based on Energy Institute's guidelines and observed that the piping system is in concern/problem zones. The process study including review of hydraulics, verification of line size and control valve design was performed to identify the root cause of piping vibration. The piping stress analysis (static/dynamic) was carried out with actual operating conditions, which is under multiphase flow with varying density/forces. The process study revealed that the flow velocity and momentum are within process design requirements. However the flow in the piping system is multi-phase type, which generates unbalanced forces due to slug loads at each elbow of the piping system. Based on piping stress analysis results, it was identified that the natural frequency of piping systems is variable as the whole weight of the vertical piping system is resting on spring type supports, which in turn, are supported from vertical vessel cleats. These supports are provided to take care of relative displacements between vessel and vertical piping systems. Piping configuration cannot be modified considering large bore piping and requirement of huge structural supports. The existing supports also cannot be modified as they are connected to pressure vessel and will impact its design. In this scenario of multiple limitations, the indispensable flow induced vibrations of piping can only be minimized by damping the effect of flow-induced excitation with dampers. The dampers have elastic-viscous material in its main restraining body which can absorb the piping vibrations. The damper vendor performed the stress analysis, considering the effect of the damper in the whole piping system, and ensured the integrity of piping system. The challenge of maintaining existing spring supports and achieving required damping of piping vibration was successfully accomplished. Considering large sized piping and requirement of major structural supports in case of modifications, proposed solutions could be treated as cost effective and innovative. Though it was not possible to eliminate the root cause, this alternate innovative solution helped to not only to minimize vibration, but also optimize implementation/shutdown costs. Vibration damper in piping systems is unique to piping installations.

Addition is the heart of arithmetic unit and the arithmetic unit is often the work horse of a computational circuit. So adders play a key role in designing an arithmetic unit and also many digital integrated circuits. Carry Select Adder (CSLA) is one of the fastest adders used in many data processors and in digital circuits to perform arithmetic operations. But CSLA is area-consuming because it consists of dual ripple carry adder (RCA) in the structure. To reduce the area of CSLA, a CSLA with Binary to Excess-1 Converter is already designed which reduces the area of adder. But there are other techniques to design a CSLA to reduce its area. One of such technique is using an add one circuit technique. This paper proposes the design of square root CSLA (SQRT CSLA) using add one circuit with significant reduction in area. The proposed design is synthesized using Leonardo Spectrum to get area (number of gates) and delay (ns). The performance in terms of area and delay are evaluated for square root CSLA using add one circuit and are compared with existing SQRT CSLA and SQRT CSLA using Binary to Excess-1 Converter (BEC). The results analysis shows that the proposed SQRT CSLA using add one circuit is better than the existing SQRT CSLA and SQRT CSLA using BEC.

Integrity of piping systems is critical for the safe and reliable Plant operations. Shaking or Vibration of piping systems pose potential threats to plant safety and integrity. In GASCO plants, vibrations were observed in some systems such as piping carrying two-phase flow, high pressure lines, piping associated with compressors / pumps, etc. Minimizing the pipe shaking to maximize the process safety through a systematic approach will result in economical, efficient, safe and time bound advantages. This paper presents GASCO's approach in resolving piping vibrations and mitigating the risks to plant operations. Studies were carried out to investigate the root cause and recommend required remedial measures. Walkthrough along the piping system was carried out to identify locations of high vibrations and to detect any mechanical abnormalities as first step. Process conditions were also verified for any upsets. This was followed by measurement of vibration parameters such as amplitudes, frequencies and accelerations. The data collected was analyzed and level of vibrations were classified as critical and non-critical based on recommended limits as per relevant industry standards. For the critical systems, detailed process studies / piping stress analysis were carried out by simulating actual piping vibration taking various excitation sources and as-built conditions into consideration. Theoretical results were compared with field data and were found to be consistent. In order to limit the vibrations within permissible values, necessary measures were recommended. Based on recommended modifications, revised piping stress analysis was carried out to ensure vibrations are within design limits. Implementation packages were prepared to execute the suggested remedial measures. Post-implementation vibration measurements were taken and observed to be comparable to design values and within permissible limits, thereby ensuring plant safety and integrity. Less attention paid to piping vibration during initial design phase, probably due to lack of clear and precise codes and standards, was found to be the main reason for piping vibrations. GASCO recognized the need for documenting the above best practices to address piping vibrations. The Guidelines are developed to identify/classify the severity of vibrations and the way forward to tackle the piping vibration issues which can be used by site personnel.

Finger print recognition process involves many trigonometric evolutions. CORDIC based evolution of trigonometric functions is possible. In this paper CORDIC based architecture is proposed to evaluate the trigonometric or inverse trigonometric functions like sinθ, cosθ. Proposed architecture is partitioned into two main blocks: Magnitude generator and CORDIC processor. Magnitude generator outputs the value of the trigonometric function by driving the CORDIC processor. CORDIC processor executes the CORDIC rotations. Architecture Proposed in this paper is implemented using XILINX 13.2. Performance of the architecture is analyzed by calculating the relative error and resource utilization summery is reported.