Search Results (5,743)

This paper presents the design of a Delay-Locked Loop (DLL) with a simple architecture and a wide input clock duty cycle range. The design is tailored to meet the increasing data rate and stringent clock requirements of modern semiconductor chips, with particular applicability to dynamic random-access memory (DRAM) systems. The structure features two Bang-Bang Phase Detectors (BBPDs) to adjust the rising and falling edges of the divided clock. Implemented using a 65 nm CMOS process, the design was verified through simulation. At a working frequency of 3.2 GHz, the input clock duty cycle range spans from 18% to 72%, with a maximum output clock duty cycle error of just 0.6%, a peak-to-peak jitter of 15.73 ps, and a power consumption of 12.7 mW. Full article

Railway heritage corridors, which integrate cultural history and natural landscapes, face limitations within the conventional “axis extension” construction model, where protection zones are radiated from existing railway lines. This approach hinders the development of cross-regional heritage networks and lacks scientific quantification in boundary delineation. This study proposes an innovative spatial planning paradigm for railway heritage corridors in the Beijing-Tianjin-Hebei (BTH) region, integrating railway heritage with the urban environment. Utilizing the minimum cumulative resistance model, a multidimensional resistance surface was created to identify potential corridor patterns based on centrality. Circuit theory quantified global connectivity, and statistical methods defined corridor widths. The case study identified 19 sources and 42 corridors across 54,399.42 km², with an average length of 111.48 km and width of 9.24 km. These corridors form a closed network radiating from multiple centers, offering guidance for BTH tourism planning and heritage management. Full article

The rising prevalence of geopolitical conflicts and other disruptive events threatens the globally integrated supply chain of the integrated circuit (IC) industry. To identify the key industries and key enterprises within the IC industry and clarify the key influencing factors of the industry’s resilience, this paper takes the Chinese IC industry as the research object. Firstly, this paper has achieved the quantitative modeling of China’s IC industry system by constructing a three-level industrial chain and supply chain network. Then, using the agent-based modeling simulation method, a large number of risk events were simulated, and the key risk nodes within the system were identified. Finally, through the experimental design, this study completes the analysis of the key points of the resilience capability of China’s IC industry. The results provide theoretical insights into resilience mechanisms and support evidence-based management strategies for the IC industry. Full article

Last-mile logistics is a critical operational and environmental challenge in urban areas. This paper introduces an intelligent path planning system using the Resistive Grid Path Planning Methodology (RGPPM) to optimize distribution based on energy and environmental metrics. The foundational innovation is the integration of electrical-circuit analogies, modeling the distribution network as a resistive grid where optimal routes emerge naturally as current flows, offering a paradigm shift from conventional algorithms. Using a multi-connected grid with georeferenced resistances, RGPPM estimates minimum and maximum paths for various starting points and multi-agent scenarios. We introduce five key performance indicators (KPIs)—Percentage of Distance Savings (PDS), Coefficient of Savings (CS), Coefficient of Global Savings (CGS), Percentage of Load Imbalance (PLI), and Percentage of Deviation with Multi-Agent (PDM)—to evaluate system performance. Simulations for textbook delivery to 129 schools in the Veracruz–Boca del Río area show that RGPPM significantly reduces travel distances. This leads to substantial savings in energy consumption, CO₂ emissions, and operating costs, particularly with electric vehicles. Finally, the results validate RGPPM as a flexible and scalable strategy for sustainable urban logistics. Full article

This study presents the development of a prototype anthropomorphic soft robotic gripper intended for applications in rehabilitation and assistive robotics, where safe and adaptive interaction with humans is required. The device consists of three elastomeric fingers, fabricated in TPU via FFF 3D printing and actuated through pneumatic soft actuators that ensure compliant contact with both biological tissue and rigid objects. A custom 3D-printed pneumatic rotary actuator enables finger reconfiguration, thereby extending the range of grasping modalities. The actuation system comprises six 2/2 solenoid valves controlled by an Arduino Uno and integrated into a dedicated pneumatic circuit. Experimental characterization demonstrated a peak grasping force exceeding 17 N on rigid targets, while functional tests in table-picking scenarios confirmed adaptability to objects of varying shapes and sizes. Owing to its anthropomorphic configuration, mechanical compliance, and ease of fabrication and control, the proposed gripper represents a versatile solution for rehabilitation-oriented devices as well as assistive robotic end-effectors in pick-and-place tasks. Full article

Conventional finite control set model predictive control (FCS-MPC) for permanent magnet synchronous motor (PMSM) drives suffers from a fundamental trade-off: shortening the control period improves current tracking but increases switching frequency and losses. This paper proposes a hysteresis-based variable control period MPC (HBVCP-MPC) to break this compromise. Unlike methods like direct torque control (DTC) and model predictive direct torque control (MPDTC) that use hysteresis to select voltage vectors (VV), our approach first selects the optimal VV via a cost function that balances current tracking accuracy and switching frequency. Hysteresis on the $dq$-axis currents is then employed solely to dynamically determine the application time of this pre-selected VV, which defines the variable control period. This grants continuous adjustment over the VV duration, enabling superior current tracking without a proportional rise in switching frequency. Experimental results confirm that the proposed method achieves enhanced steady-state performance at a comparable switching frequency. Full article

Ecological security barriers safeguard regional ecological security by blocking external risks and supplying internal services. However, existing research has primarily focused on optimizing the connectivity and protection of internal ecological patches within barriers. At a broader scale, there remains insufficient attention on coordinating the “blocking of external ecological risk corridors” and “connecting corridors that supply ecosystem services to internal urban areas”. To address this, this study develops a framework for constructing ecological corridors that integrates both reverse (resistance) and forward (provision) perspectives. Taking the Yanshan–Taihang Mountain Ecological Barrier as a case study, circuit theory is applied to identify risk corridors traversing the barrier area. Service supply corridors directed toward internal urban areas are also established, and key nodes along these corridors are identified. Furthermore, the XGBoost-SHAP method is employed to quantitatively analyze the influencing factors and mechanisms of these key nodes. Finally, strategies are proposed to block risk corridors and connect supply corridors. The main results are as follows: (1) A total of 29 risk corridors, 158 risk pinch points, and 210 risk barriers were identified, along with 250 supply corridors, 158 supply pinch points, and 118 supply barriers, revealing the distinct distribution patterns of both risk transmission and service supply corridors. (2) The dominant factors influencing different types of corridors exhibited significant differences: risk corridors were primarily regulated by natural factors such as mean annual evapotranspiration (EVA) and soil volumetric water content (VWC), whereas supply corridors were mainly influenced by human activities, including the human footprint index (HFP) and land surface temperature (TEM). (3) Even within the same type of corridor, the dominant factors and their operating mechanisms—such as threshold effects and nonlinear interactions—showed considerable heterogeneity across nodes of different characteristics. Based on these findings, differentiated policy recommendations were proposed. This study aims to synergistically enhance the bidirectional functionality of forest-mountain ecological barriers by disrupting external risk corridors and reconstructing internal supply networks. The framework and methodology presented here can provide theoretical and empirical references for the planning and management of other similar barrier regions. Full article

As the complexity of Very-Large-Scale Integration (VLSI) circuits escalates, Design-for-Test (DFT) faces significant challenges. Traditional script-based automation flows are increasingly complex and present a high technical barrier for non-specialists. In order to overcome the above issue, this paper introduces DFTAgent, a novel framework that leverages Large Language Models to intelligently orchestrate a DFT toolchain. DFTAgent is evaluated on the ISCAS’85, ISCAS’89, and ITC’99 benchmarks. The results demonstrate that DFTAgent successfully completes the complete ATPG task cycle, achieving fault coverage comparable to a manually scripted baseline while exhibiting significant advantages in flexibility and error handling. By abstracting complex DFT tools behind a natural language interface and a visual workflow, this approach promises to democratize access to advanced VLSI testing methodologies and accelerate design cycles. Full article

The widespread integration of low-power electronic devices in IoT, biomedical, and sensing applications has intensified the demand for energy-autonomous solutions. Radio Frequency Energy Harvesting (RFEH) offers a promising alternative by leveraging ambient RF signals available in both indoor and outdoor environments. Despite its conceptual appeal, practical deployment still faces major challenges. This systematic literature review (SLR) examines 25 recent studies, following the PRISMA methodology, to provide a comprehensive overview of current RFEH architectures. It focuses on three critical components: receiving antennas, impedance matching circuits (IMCs), and RF-to-DC rectifiers. Design strategies are reviewed and compared across antenna types, matching techniques, and rectifier configurations. The review also highlights persistent challenges and outlines directions for the development of compact, efficient, and robust energy-harvesting systems for next-generation wireless technologies. Full article

Immersion deep ultraviolet (DUV) lithography remains an indispensable core technology in advanced integrated circuit manufacturing, particularly when combined with multiple patterning techniques to achieve sub-10 nm feature patterning. However, at advanced technology nodes, dynamic instabilities of DUV light sources—including spectral characteristics (bandwidth fluctuations, and center wavelength drift), coherence variations, and pulse-to-pulse energy instability—can adversely affect imaging contrast, normalized image log-slope (NILS), and critical dimension (CD) uniformity. To quantitatively assess the impact of laser parameter fluctuations on NILS and CD, this work establishes systematic physical models for imaging perturbations caused by multi-parameter laser output instabilities under immersion DUV lithography. Through simulations, we evaluate the influence of laser parameter variations on the imaging fidelity of representative line/space (L/S) and tip-to-line (T2L) structures, thereby validating the proposed perturbation model. Research demonstrates that the spectral attributes (bandwidth fluctuation and center wavelength drift), coherence variations, and pulse energy instability collectively induce non-uniform electric field intensity distribution within photoresist, degrading NILS, and amplifying CD variation, which ultimately compromise pattern fidelity and chip yield. Notably, at advanced nodes, pulse energy fluctuation exerts a significantly greater influence on imaging errors compared to bandwidth and wavelength variations. To satisfy the 10% process window requirement for 45 nm linewidths, pulse energy fluctuations should be rigorously confined within 1%. This research provides theoretical foundations and practical insights for the design of dynamic stability control of light source and process optimization of next-generation DUV light sources. Full article

This paper presents a design approach for a dual-band substrate-integrated waveguide (SIW) bandpass filter (BPF) featuring passband tunability and wide-stopband characteristics. The proposed circuit is realized using half-mode (HM) SIW cavities loaded with tunable stopband resonators (TSRs). The TSRs are realized using transmission lines and varactor diodes. Passband tunability can be achieved by adjusting the supply voltage on the varactor diode. Wide-stopband characteristics can be achieved by integrating the defected microstrip structure into the proposed circuit. To validate the proposed concept, dual-band HM SIW BPFs with fixed and tunable passbands has been designed and fabricated. Based on the measurement results, the proposed circuits demonstrate high-frequency selectivity, with an attenuation level better than 20 dB and measured up to more than 40 GHz at the highest stopband. Moreover, the proposed tunable dual-band HM SIW BPF provides a passband tuning range of 240 MHz, measured from 4.88 GHz to 5.12 GHz for the first passband, and 310 MHz, measured from 6.19 GHz to 6.5 GHz for the second passband. Within the passband tuning range, the insertion loss varied from 1.7 dB to 2.2 dB for the first passband and 2.1 dB to 2.5 dB for the second passband. Full article

With continued CMOS scaling, transistor miniaturization has significantly raised SRAM integration density while lowering the critical charge (Qc), increasing cell vulnerability to spaceborne high-energy particles. Single-event upset (SEU) and especially single-event multiple node upsets (SEMNU) due to charge sharing present major reliability challenges. To overcome these issues, this study introduces a radiation-hardened 20T SRAM cell with read/write optimization (RWO-20T) designed for space applications. Benchmarking against hardened cells RH14T, RHSCC16T, S8P8N16T, and CC18T reveals that RWO-20T delivers superior read static noise margin (RSNM), increased word-line write trip voltage (WWTV), and faster read and write access times. Although the higher transistor count incurs some area overhead and slightly lowers the hold static noise margin (HSNM), RWO-20T achieves improved recovery rates for dual-node upsets (DNU) and triple-node upsets (TNU) under SEMNU conditions. The circuits were simulated in a 90 nm CMOS process and operated at 1 V. Full article

The mammalian target of rapamycin (mTOR) is a serine/threonine kinase that integrates metabolic and environmental signals to regulate cell growth and survival. In the central nervous system, mTOR plays a pivotal role in neuronal development, plasticity, and circuit homeostasis. In diffusely infiltrating gliomas, including glioblastomas, mTOR signaling is frequently dysregulated and contributes to malignant progression, therapeutic resistance, and metabolic adaptation. Beyond tumor-intrinsic effects, recent evidence reveals that gliomas actively reprogram peritumoral neurons via mTOR-dependent mechanisms, leading to synaptic remodeling, hyperexcitability, and neurological symptoms such as seizures and cognitive dysfunction. These results position mTOR as a central mediator of both oncogenesis and neurological dysfunction in diffusely infiltrating glioma. While clinical trials of mTOR inhibitors in gliomas have so far shown limited efficacy, emerging data suggest these agents may ameliorate tumor-associated neurological dysfunction. This review synthesizes current knowledge of mTOR signaling across tumor and neuronal compartments in diffusely infiltrating glioma and highlights its potential as a therapeutic target at the intersection of cancer biology and neuroscience. Full article

The convergence of Internet of Things (IoT) and Artificial Intelligence (AI) has enabled personalized sports coaching, yet a significant gap remains: translating low-level sensor data into high-level, contextualized feedback. Large Language Models (LLMs) excel at reasoning and instruction but lack a native understanding of physical kinematics. This paper introduces BoxingPro, a novel framework that bridges this semantic gap by fusing wearable sensor data with LLMs for automated boxing coaching. Our core contribution is a dedicated translation methodology that converts multi-modal time-series data (IMU) and visual data (video) into structured linguistic prompts, enabling off-the-shelf LLMs to perform sophisticated biomechanical reasoning without extensive retraining. Our evaluation with professional boxers showed that the generated feedback achieved an average expert rating of over 4.0/5.0 on key criteria like biomechanical correctness and actionability. This work establishes a new paradigm for integrating sensor-based systems with LLMs, with potential applications extending far beyond boxing to any domain requiring physical skill assessment. Full article

This paper addresses the issue of existing research that fails adequately capture the spatiotemporal nonstationarity caused by the building of occlusion and flight dynamics in air-to-ground channels from unmanned aerial vehicles (UAVs) in urban scenarios. This study focuses on the angular-altitude correlations of three key metrics: path loss (PL), shadow fading, and the Ricean K-factor. A dynamic path-loss model incorporating the look-down angle is proposed, an exponential decay model for the shadow-fading standard deviation is constructed, and a model for the angle-dependent variation of the Ricean K-factor is established based on line-of-sight probability. Simulations were conducted in two urban-geometry scenarios using WinProp to evaluate the combined effects of flight altitude and elevation angle. The results indicate that path loss decreases and subsequently stabilizes with increasing elevation angle, the shadow-fading standard deviation decreases significantly, and the Ricean K-factor increases with angle and saturates at high angles, in agreement with theoretical predictions. These models are more adaptable to UAV mobility scenarios than traditional fixed exponential models and provide a useful basis for UAV link planning and system optimization in urban environments. Full article