Physical Verification Research Articles

Implementation of Adders using XOR gates in Quantum-Dot Cellular Automata with Physical Verification

Abstract This paper presents a promising approach to nanoscale computing, offering significant advantages through the QCA technology. It suggests a highly efficient, scalable, and reliable multilayered QCA half and full adder circuits, leveraging a three-input QCA XOR gate. The proposed full adder layout demonstrates significant improvements in various parameters, including area, latency, and energy dissipation. In particular, it offers 17% greater area efficiency and utilizes 14 fewer cells compared to the best work existing work. We thoroughly evaluated energy dissipation using the QCADesigner-E tool. We also examined the cost functions, with a QCA-specific cost of 22 units, which is ~37% better than earlier designs. The architecture is strategically designed with externally accessible input and output nodes to ensure seamless scalability. Physical reliability is ensured through kink energy calculations for the suitability of higher-order circuit designs. Practical applications of the proposed blocks include their use in arithmetic logic units (ALUs), digital signal processors, and other modern processing and computing systems. This work sets a new benchmark for future developments in QCA technology, offering a robust, efficient, and versatile solution for advanced nano-processing and computing systems.

A multi-strategy improved sparrow search algorithm for indoor AGV path planning

To address the problems of weak search ability, easily falling into local optimal solutions and poor path quality of sparrow search algorithm in AGV path planning, a multi-strategy improved sparrow search algorithm (MISSA) is proposed in this paper. MISSA improves the global search ability by improving the discoverer position update operator and introducing the sine cosine algorithm; adopts the adaptive number of vigilantes and adaptive adjustment step size to improve the convergence speed; introduces the Levy flight variation strategy to reduce the probability of falling into any local optimal solution; optimizes the boundary handling mechanism to prevent the loss of population diversity at a later stage; finally, uses the large-scale neighborhood search strategy and path smoothing mechanism for path optimization to further improve the path quality. The superiority-seeking ability of MISSA was verified by 12 standard test functions, and then 30 simulation experiments were conducted in grid maps with two specifications of 20×20 and 30×30. The experimental results showed that, by using MISSA, the path length was reduced by 44.1% and 63.1%, the number of turns was reduced by 68.4% and 78.4%, and the risk degree was reduced by 61.3% and 77.2%, which verifies the superiority of MISSA in path planning. Finally, MISSA was ported to the QBot2e mobile robot for physical verification to prove its feasibility in practical applications.

Smart-CX – Method of extraction of parasitic capacitances in ICs

This paper proposes a novel rule-based parasitic capacitance extraction methodology, integrated into Smart-CX, to enhance the accuracy of SPICE simulations and physical verification of ICs. This methodology is crucial during the microchip design phase, particularly in preparation for fabrication on mature to advanced process nodes. The proposed enhanced analytical method addresses the accuracy/time tradeoffs between numerical and analytical extraction techniques. This study validates the accuracy of the methodology by comparison of the extracted parasitic parameters with foundry-provided 2D-models. The parasitic capacitances that are extracted within this method include: area capacitances (Ca), coupling capacitances (Cc), including via-to-via capacitances (Cmv), contact-to-gate capacitances (Cmg), contact-to-active capacitances (Cmc) and fringe type capacitances with the top (Cft) and bottom (Cfb) conductive layers.

Modified Universal Kriging-based clearance error optimization for orthogonal robot

Abstract Aiming at the problem that the clearance error of the traditional tire laser engraving robot is too high, and thus the resulting positioning accuracy cannot meet the accuracy requirements needed for engraving at this stage, this paper takes the homemade orthogonal robot as the object of research, and researches the optimization method of the positioning error of the orthogonal robot based on the modified Kriging. In this paper, we use spinor theory to construct a robot clearance error model, establish an objective function with orthogonal robot clearance error as the optimization objective, and use a particle swarm algorithm to modify universal kriging (MUK) to optimize the positioning error. The optimization method is simulated and analyzed, and MUK is selected for comparison with other optimization methods. The simulation results show that 52% relative reduces the number of iterations of the MUK to the universal kriging model (UK), 79% relative to the particle Swarm Optimization (PSO), and 81% relative to the ordinary kriging model (OK), which makes the algorithm better applicable in comparison. At the same time, a tire laser engraving orthogonal robot experimental platform was built for physical verification experiments, and the experimental results show that the maximum error before and after the optimization of the integrated error of orthogonal robot positioning accuracy has been reduced by 89.91%; the average positioning error has been reduced by 86.90%; and the root-mean-square error has been reduced by 83.01%, which further proves the practicability of the proposed method.

Interpretable Data‐Driven Descriptors for Establishing the Structure‐Activity Relationship of Metal‐Organic Frameworks Toward Oxygen Evolution Reaction

The development of readily accessible and interpretable descriptors is pivotal yet challenging in the rational design of metal‐organic framework (MOF) catalysts. This study presents a straightforward and physically interpretable activity descriptor for the oxygen evolution reaction (OER), derived from a dataset of bimetallic Ni‐based MOFs. Through an artificial‐intelligence (AI) data‐mining subgroup discovery (SGD) approach, a combination of the d‐band center and number of missing electrons in eg states of Ni, as well as the first ionization energy and number of electrons in eg states of the substituents, is revealed as a gene of a superior OER catalyst. The found descriptor, obtained from the AI analysis of a dataset of MOFs containing 3‐5d transition metals and 13 organic linkers, has been demonstrated to facilitate in‐depth understanding of structure–activity relationship at the molecular orbital level. The descriptor is validated experimentally for 11 Ni‐based MOFs. Combining SGD with physical insights and experimental verification, our work offers a highly efficient approach for screening MOF‐based OER catalysts, simultaneously providing comprehensive understanding of the catalytic mechanism.

Interpretable Data-Driven Descriptors for Establishing the Structure-Activity Relationship of Metal-Organic Frameworks Toward Oxygen Evolution Reaction.

The development of readily accessible and interpretable descriptors is pivotal yet challenging in the rational design of metal-organic framework (MOF) catalysts. This study presents a straightforward and physically interpretable activity descriptor for the oxygen evolution reaction (OER), derived from a dataset of bimetallic Ni-based MOFs. Through an artificial-intelligence (AI) data-mining subgroup discovery (SGD) approach, a combination of the d-band center and number of missing electrons in eg states of Ni, as well as the first ionization energy and number of electrons in eg states of the substituents, is revealed as a gene of a superior OER catalyst. The found descriptor, obtained from the AI analysis of a dataset of MOFs containing 3-5d transition metals and 13 organic linkers, has been demonstrated to facilitate in-depth understanding of structure-activity relationship at the molecular orbital level. The descriptor is validated experimentally for 11 Ni-based MOFs. Combining SGD with physical insights and experimental verification, our work offers a highly efficient approach for screening MOF-based OER catalysts, simultaneously providing comprehensive understanding of the catalytic mechanism.

Simulation study of physical cryptographic verification of nuclear warheads based on NRF excited by LCS γ-ray source

The nuclear resonance fluorescence (NRF) can provide a unique physical fingerprint, and had played an important role in the physical cryptographic verification of nuclear warheads on bremsstrahlung-based system. In this work, an alternative method using laser-Compton scattering (LCS) γ-ray source to excite NRF for physical cryptographic verification of nuclear warheads is proposed, and Monte Carlo simulation is performed by Geant4. This research indicates that the LCS-based system exhibits a high discernment capability for isotope hoaxes and geometric hoaxes, while maintaining low radiation dose. Moreover, it exhibits a more effective ability to avoid leakage of isotopic and geometric information, and is believed that the LCS-based system has better safety potential compared to the bremsstrahlung-based system. This work indicates that the LCS-based system can provide a possible and promising approach in verification of nuclear warheads in the future.

Structural design and coupling analysis of multimode variable coupling parallel mobile robots

Purpose There is coupling between the branches of mobile parallel robots, similar to traditional parallel mechanisms, but there is currently relatively little research on the coupling problem between the branches of mobile parallel robots. Design/methodology/approach This study optimizes the coupling analysis method of traditional parallel mechanisms, treats the mobile parallel mechanism as a whole, takes the motion of the active pair as input and the overall motion of the mobile parallel mechanism as output and analyzes the input–output characteristics of the mobile parallel mechanism. Moreover, this study applies this theory to a mobile parallel mechanism, designs control logic and finally conducts simulation and physical verification. Findings This study proposes a coupling analysis method suitable for parallel mobile robots and designs the control logic of their active pair based on the results of their coupling analysis. This study designs a multimode variable coupling parallel mobile robot, which can change the coupling of the mechanism by changing its own branch chain structure, so that it can switch between different coupling configurations to meet the different needs brought by different terrains. Originality/value The work presented in this paper propose a method for analyzing the coupling of mobile parallel robots and simplify their control logic by applying coupling theory to the design of mobile parallel robots. This study conducts simulation and physical experiments, thereby filling the gap in the coupling analysis of parallel mobile robots and laying the foundation for the research of uncoupled parallel mobile robots.

An Efficient, Fast and Accurate Online Signature Verification Using Blended Feature Vector and Deep Learning

Online signature verification is one of the biometric authentication techniques. Online signature verification reduces the human error that may occur due to physical signature verification. Many researchers have provided a method of online signature verification still there is a scope for improvement. In this paper, a novel blended feature vector (BFV) is formed by combining two feature vectors. The first of these feature vectors is formed using a raw online signature database and the other feature vector is formed of the features extracted from the grayscale images obtained from the signature database. The algorithm makes use of the probability distribution of the features to provide a feature vector that results in an enhanced verification system. Two online signature databases, namely SVC2004 and ATVS-SSig are used. BFV is used to train the proposed mixed sequence deep neural network (MS-DNN). The use of a blended feature vector in the training of MS-DNN, instead of a whole online signature database, improves the training time of deep neural network to a great extent. This reduction in training time might be useful for new user registration. The performance parameters considered are validation efficiency and equal error rate. Results are compared with the existing state of technology and the comparison shows that the use of a blended feature vector as a classification vector improves the validation efficiency (99.5%) and also there is an improvement in the verification success rate in terms of equal error rate (EER 1.5%) as compared to the existing research.

The study of lithographic variation in resistive random access memory

Reducing the process variation is a significant concern for resistive random access memory (RRAM). Due to its ultra-high integration density, RRAM arrays are prone to lithographic variation during the lithography process, introducing electrical variation among different RRAM devices. In this work, an optical physical verification methodology for the RRAM array is developed, and the effects of different layout parameters on important electrical characteristics are systematically investigated. The results indicate that the RRAM devices can be categorized into three clusters according to their locations and lithography environments. The read resistance is more sensitive to the locations in the array (~30%) than SET/RESET voltage (<10%). The increase in the RRAM device length and the application of the optical proximity correction technique can help to reduce the variation to less than 10%, whereas it reduces RRAM read resistance by 4×, resulting in a higher power and area consumption. As such, we provide design guidelines to minimize the electrical variation of RRAM arrays due to the lithography process.

Enhancing acoustic levitation capacity through array geometry optimization

The contactless micromanipulation capability and microgravity environment provided by the acoustic levitation technology have excellent application prospects in many fields, such as droplet dynamics, solidification state physics, life sciences, etc. However, the applications are severely constrained by the limitation of the transducer power. In this paper, we explore an array geometry optimization framework to improve the levitation capability. First, the acoustic pressure attenuation and directional characteristics of commercial transducers are analyzed to uncover the mechanism of the array geometry affecting the acoustic radiation force (ARF). Second, based on the Gor'kov potential theory, the array geometry form of N-elements is derived, and the arrangement in the spherical ring (ASR) method is proposed to obtain the element coordinates. Then, spherical radius and array height are adjusted to obtain the optimal array geometry. On this basis, the directional angle of each transducer is further optimized. Finally, simulation and physical verification are carried out. The simulation results indicate that the ARF increases and then decreases with the spherical radius and array height, which are the existing maximum values. Directional angle optimization (DAO) can improve the ARF, particularly when the array height exceeds the sphere diameter. These findings are consistent with the analytical results. Notably, we built a prototype physical system, and the physical experiments showed that the optimized array improved the axial ARF by 201.2% and the radial ARF by 115.9% over the conventional array. The works presented in this paper offer a valuable design approach for acoustic levitation arrays, thereby contributing to the advancement and application of ultrasonic array levitation technology.

Control and physical verification of 6-DOF manipulator for power inspection robots based on expert PID algorithm

To enhance the performance of power inspection robots in intricate nuclear power stations, it is necessary to improve their response speed and accuracy. This paper uses the manipulator of the power inspection robot as the primary research object, and unlike previous control algorithm research, which only remained in the software simulation stage, we constructed a set of physical verification platforms based on CAN communication and physically verified the robotic arm’s control algorithm. First, the forward motion model is established based on the geometric structure of the manipulator and D-H parameter method, and the kinematic equation of the manipulator is solved by combining geometric method and algebraic method. Secondly, in order to conduct comparison tests, we designed PID controllers and expert PID controllers by utilising the expertise of experts. The results show that compared with the traditional PID algorithm, the expert PID algorithm has a faster response speed in the control process of the manipulator. It converges quickly in 0.75 s and has a smaller overshoot, with a maximum of only 6.9%. This confirms the expert PID algorithm’s good control effect on the robotic arm, allowing the six-degree-of-freedom robotic arm to travel more accurately and swiftly along the trajectory of the target point.

Повышение формализации задач верификации топологии и электрической схемы для систем автоматизированного проектирования

The article discusses the study of methods for checking the conformity of the topology and electrical circuit in electronic devices. The authors present a new approach to the analysis and verification of topological structure taking into account electrical characteristics, which leads to increased formalization of problems and provides better optimization of interaction between a person and a computer CAD system. The study includes an analysis of modern methods and tools used in the electronic device design process, and also proposes innovative approaches to ensure consistency between topology and electrical functionality. LVS verification of the project using Caliber, xRC extraction of the project, physical verification of the project using CAD software Cadence Physical Verification System (PVS), LVS verification of the project using PVS are performed. Presents a detailed analysis of the integrated circuit verification process performed using modern CAD tools. The work examines the key stages of verification, including LVS verification of the project using the Caliber tool, xRC extraction of the project, as well as physical verification of the project using the Cadence Physical Verification System (PVS). Particular attention is paid to LVS checks, which are an important design step to ensure compliance with the topology and electrical design. The features of using Caliber to perform LVS checks are discussed, as well as the xRC extraction process to extract parameters of resistors and capacitors. For physical verification of the project, the capabilities of Cadence PVS were used, which provides analysis of compliance of the physical implementation of the circuit with the specified rules. The results obtained and the experience presented in the article can be useful for engineers and researchers involved in the design of integrated circuits, as well as for those interested in the application of modern CAD tools in the field of verification and validation of electronic devices.

Research on Image Processing Resource Reconstruction Based on Load Balancing Strategy

With the development of intelligent vehicles, the vehicle image processing system has put forward increasing demand for computing resource utilization efficiency and real-time processing. However, the traditional information processing method that binds software and hardware severely restricts the efficient use of image processing resources. In order to solve this problem, this paper proposes a resource reconstruction scheme based on a load balancing strategy, which can realize unified management and dynamic allocation of image processing resources by establishing a system resource view. Then, this paper builds a physical verification platform and constructs a comparative verification experiment to verify the effectiveness of the resource reconstruction scheme. Experimental results prove that this resource reconstruction scheme can effectively improve the resource utilization efficiency of multi-core digital signal processing (DSP), realize software-defined hardware functions, and optimize the real-time performance of parallel processing.

ДОСЛІДЖЕННЯ ПОДВІЙНИХ ЗАМКНЕНЬ НА ЗЕМЛЮ В МЕРЕЖАХ 10 КВ З ІЗОЛЬОВАНОЮ НЕЙТРАЛЛЮ

Reliability indicators of power supply systems as a whole are largely determined by the level of reliability of distribution electrical networks with a voltage of 6-35 kV. Emergency in networks with a voltage of 6-35 kV, operating in the mode with an isolated neutral, is often associated with internal overvoltages. Single-phase short-circuits occur in places of defects in the insulation of cable lines and substation equipment due to the aging of the insulation, non-compliance with the manufacturing technology of insulating structures at factories, non-compliance with the requirements of the instructions during the installation and operation of the equipment, as well as due to mechanical damage, which, sometimes at the time of their appearance, lead to only a partial decrease in electrical strength. Overloads lead to defects. Single-phase short-circuits in 10 kV networks that are not eliminated in time can lead to double earth faults. For protection in these networks, such protections as current cut-off, maximum current protection, current cut-off, zero-sequence current protection, current protections with blocking at minimum voltage are used. However, there are cases when there are cases of negative operation of such protections at a 10 kV substation during double earth faults. For example, a phase A short circuit occurred on the first line, which receives power from the buses of the investigated substation, and another short circuit (phase B) occurred on the second line. Instead of tripping the two damaged lines, the input circuit breaker tripped by mistake. This de-energized other (undamaged) lines that are fed from the same bus section as the damaged lines. Under such conditions, further studies of the currents in the lines during double circuits are required. For this, the use of the Matlab application program package is justified. This will significantly reduce the costs of physical modeling and verification of proposed proposals. The paper presents the results of studies of double earth faults in 10 kV networks with an isolated neutral in the "MATLAB" program package.

Nanodosimetric quantity-weighted dose optimization for carbon-ion treatment planning.

Dose verification of treatment plans is an essential step in radiotherapy workflows. In this work, we propose a novel method of treatment planning based on nanodosimetric quantity-weighted dose (NQWD), which could realize biological representation using pure physical quantities for biological-oriented carbon ion-beam treatment plans and their direct verification. The relationship between nanodosimetric quantities and relative biological effectiveness (RBE) was studied with the linear least-squares method for carbon-ion radiation fields. Next, under the framework of the matRad treatment planning platform, NQWD was optimized using the existing RBE-weighted dose (RWD) optimization algorithm. The schemes of NQWD-based treatment planning were compared with the RWD treatment plans in term of the microdosimetric kinetic model (MKM). The results showed that the nanodosimetric quantity F3 - 10 had a good correlation with the radiobiological effect reflected by the relationship between RBE and F3 - 10. Moreover, the NQWD-based treatment plans reproduced the RWD plans generally. Therefore, F3 - 10 could be adopted as a radiation quality descriptor for carbon-ion treatment planning. The novel method proposed herein not only might be helpful for rapid physical verification of biological-oriented ion-beam treatment plans with the development of experimental nanodosimetry, but also makes the direct comparison of ion-beam treatment plans in different institutions possible. Thus, our proposed method might be potentially developed to be a new strategy for carbon-ion treatment planning and improve patient safety for carbon-ion radiotherapy.

Exceptional mechanical performance by spatial printing with continuous fiber: Curved slicing, toolpath generation and physical verification

This work explores a spatial printing method to fabricate continuous fiber-reinforced thermoplastic composites (CFRTPCs), which can achieve exceptional mechanical performance. For models giving complex 3D stress distribution under loads, typical planar-layer based fiber placement usually fails to provide sufficient reinforcement due to their orientations being constrained to planes. The effectiveness of fiber reinforcement could be maximized by using multi-axis additive manufacturing (MAAM) to better control the orientation of continuous fibers in 3D-printed composites. Here, we propose a computational approach to generate 3D toolpaths that satisfy two major reinforcement objectives: (1) following the maximal stress directions in critical regions and (2) connecting multiple load-bearing regions by continuous fibers. Principal stress lines are first extracted in an input solid model to identify critical regions. Curved layers aligned with maximal stresses in these critical regions are generated by computing an optimized scalar field and extracting its iso-surfaces. Then, topological analysis and operations are applied to each curved layer to generate a computational domain that preserves fiber continuity between load-bearing regions. Lastly, continuous fiber toolpaths aligned with maximal stresses are generated on each surface layer by computing an optimized scalar field and extracting its iso-curves. A hardware system with dual robotic arms is employed to conduct the physical MAAM tasks depositing polymer or fiber reinforced polymer composite materials by applying a force normal to the extrusion plane to aid consolidation. When comparing to planar-layer based printing results in tension, up to 644% failure load and 240% stiffness are observed on shapes fabricated by our spatial printing method. We demonstrate the versatility of our approach through various complex load cases which demonstrate their successful implementation of continuous fiber printing in 3D.

Trajectory planning of tire laser engraving orthogonal robot based on an improved multi-objective grasshopper optimization algorithm

The traditional tire laser engraving robots have the low and stable running capability and discontinuous motion trajectory during operation, leading to long running time, high energy consumption, and uneven operation. In order to solve these problems, this paper proposes an orthogonal robot trajectory planning method based on an improved multi-objective grasshopper optimization algorithm (IMOGOA) with the orthogonal robot as the research object. Firstly, this paper used the quintic non-uniform rational b-splines (NURBS) curves to construct the trajectory. Secondly, the optimization objectives of the orthogonal robot’s running time, energy consumption, and smoothness were used to obtain the Pareto optimal solution by using the IMOGOA to establish the objective function. Then, the optimization method was simulated and analyzed, and the optimal solution was selected to compare with the rest of the non-dominated solution sets. The simulation results showed that the proposed method reduced the running time by 33.68%, improved the energy consumption and smoothness performance by 34.48% and 56.58%, and achieved multi-objective comprehensive optimization of the orthogonal robot. Thus, the effectiveness and feasibility of the proposed method were verified. Finally, a tire laser engraving orthogonal robot experimental platform was built for physical verification experiments. The experimental results showed that the experimental trajectory deviated from the simulated trajectory by only 5.63%, further proving the proposed method’s practicality.

Pattern Matching for Feasible and Efficient Physical Design Verification of Cell Libraries

Pattern Matching for Feasible and Efficient Physical Design Verification of Cell Libraries

Интеграция программного продукта Calibre в среду Cadence Virtuoso и повышение интеллектуальных свойств САПР проектировании микросхем

The article discusses the technology for integrating Caliber into the Cadence Virtuoso environment and describes the impact of this integration on the productivity of engineers. The possibility of ensuring optimal interaction between developers and increasing the overall efficiency of the design team is considered, leading to end-to-end design optimization. The integration of Caliber and Cadence Virtuoso represents an important step in Electronic Design Development (EDA) and can solve a number of problems while improving the efficiency of the verification and analysis process. Here are a few aspects that demonstrate the need and benefits of such integration, data interoperability, ensuring that information received from Virtuoso can be used correctly and efficiently in Caliber and vice versa, automating the data transfer process and performing verification, speeding up all development cycles, verification can carry out, even in the early stages of design, smoother interaction between different teams using Virtuoso and Caliber. In the second part of the article, physical verification and extraction of the project is carried out using the graphical interface of the Mentor Graphics Caliber CAD system, where the topology is checked for compliance with the CTO (DRC check). For the DRC check of a project, check is performed using the Caliber application. Using Caliber in Cadence Virtuoso allows for more accurate verification of designed electronic circuits and microchips. Caliber provides deeper analysis of physical parameters such as layer compatibility, electrical and geometric rules, leading to the identification of potential problems earlier in development.