Search Results (199)

With the high penetration of renewable energy integrated into the power grid, the system exhibits strong randomness and volatility. To balance these uncertainties, a large amount of flexible regulating resources is required. This paper proposes an optimization method based on a Seq2Seq Transformer model, which takes stochastic renewable energy and load data as inputs and outputs the allocation ratios of various regulating resources. The method considers renewable energy stochasticity, power flow constraints, and adjustment characteristics of different regulating resources, while constructing a multi-objective loss function that integrates ramping response matching and cost minimization for comprehensive optimization. Furthermore, a multi-feature perception attention mechanism for stochastic renewable energy is introduced, enabling better coordination among resources and improved ramping speed adaptation during both model training and result generation. A multi-solution optimization framework with Pareto-optimal filtering is designed, where the Decoder outputs multiple sets of diverse and balanced allocation ratio combinations. Simulation studies based on a regional power grid demonstrate that the proposed method effectively addresses the problem of regulating resource capacity optimization in new-type power systems. Full article

Accessing the built environment poses many challenges for people with disabilities, severely affecting their independence and quality of life. A panel of experts with a lived experience of disabilities co-designed a survey capturing the challenges in New Zealand’s public places. There were 319 survey respondents with impairments related to mobility (66.5%), vision (18.8%), hearing (5.0%), sensory processing and cognition (8.8%). They perceived sports stadiums as the least accessible venue, followed by bars, boutique shops and public toilets. The most accessible venues were supermarkets, libraries and shopping malls. The type of disability affected the main accessibility challenges. Significant outdoor barriers included uneven and cluttered paths, inadequate provision of curb cuts, seating and accessible parking spaces, and obscure wayfinding. Entrance barriers included heavy doors, complex access control, remote ramps and narrow, obscure entrances. Interior problems included cluttered paths and poor signage. The top priorities for improvement were simplifying layouts, keeping paths clear, and providing clear, inclusive signage, communication and assistance for people with varying impairments. Providing lower counters, better colour contrast, hearing loop facilities and better control of lighting and acoustics also improve accessibility. This research contributes novel experiential data from people with disabilities that is critical to achieving an inclusive built environment. Full article

The thermal, thermomechanical, and viscoelastic properties of continuous unidirectional (UD) glass fiber/high-density polyethylene (GF/HDPE) and ultra-high-molecular-weight polyethylene/high-density polyethylene (UHMWPE/HDPE) tapes are characterized in this paper in order to support their use in extreme environments. Unlike prior studies that focus on short-fiber composites or limited thermal conditions, this work examines continuous fiber architectures under five operational environments derived from Army Regulation 70-38, reflecting realistic defense-relevant extremes. Differential scanning calorimetry (DSC) was used to identify melting transitions for GF/HDPE and UHMWPE/HDPE, which guided the selection of test conditions for thermomechanical analysis (TMA) and dynamic mechanical analysis (DMA). TMA revealed anisotropic thermal expansion consistent with fiber orientation, while DMA, via strain sweep, temperature ramp, frequency sweep, and stress relaxation, quantified their temperature- and time-dependent viscoelastic behavior. The frequency-dependent storage modulus highlighted multiple resonant modes, and stress relaxation data were fitted with high accuracy (R² > 0.99) to viscoelastic models, yielding model parameters that can be used for predictive simulations of time-dependent material behavior. A comparative analysis between the two material systems showed that UHMWPE/HDPE offers enhanced unidirectional stiffness and better low-temperature performance. At the same time, GF/HDPE exhibits lower thermal expansion, better transverse stiffness, and greater stability at elevated temperatures. These differences highlight the impact of fiber type on thermal and mechanical responses, informing material selection for applications that require directional load-bearing or dimensional control under thermal cycling. By integrating thermal and viscoelastic characterization across realistic operational profiles, this study provides a foundational dataset for the application of continuous fiber thermoplastic tapes in structural components exposed to harsh thermal and mechanical conditions. Full article

This study investigates the influence of rotation on wave propagation in a semiconducting nanostructure thermoelastic solid subjected to a ramp-type heat source within a two-temperature model. The thermoelastic interactions are modeled using the two-temperature theory, which distinguishes between conductive and thermodynamic temperatures, providing a more accurate description of thermal and mechanical responses in semiconductor materials. The effects of rotation, ramp-type heating, and semiconductor properties on elastic wave propagation are analyzed theoretically. Governing equations are formulated and solved analytically, with numerical simulations illustrating the variations in thermal and elastic wave behavior. The key findings highlight the significant impact of rotation, nonlocal parameters $e_{0}a$, and time derivative fractional order (FO) $\alpha$ on physical quantities, offering insights into the thermoelastic performance of semiconductor nanostructures under dynamic thermal loads. A comparison is made with the previous results to show the impact of the external parameters on the propagation phenomenon. The numerical results show that increasing the rotation rate $\mathsf{\Omega }=5$ causes a phase lag of approximately 22% in thermal and elastic wave peaks. When the thermoelectric coupling parameter ${\mathsf{\epsilon }}_3$ is increased from $-0.8\times {10}^{-42}$ to $1.2\times {10}^{-42}$. The temperature amplitude rises by 17%, while the carrier density peak increases by over 25%. For nonlocal parameter values $\mathsf{\epsilon }=0.3\to 0.6$, high-frequency stress oscillations are damped by more than 35%. The results contribute to the understanding of wave propagation in advanced semiconductor materials, with potential applications in microelectronics, optoelectronics, and nanoscale thermal management. Full article

As autonomous vehicles (AVs) are gradually integrated into existing traffic systems, understanding their impact on freeway operations becomes essential for effective infrastructure planning and policy design. This study explores how AV penetration rates, behavior profiles, and freeway geometry interact to influence traffic performance and safety. Using microscopic simulations in VISSIM (a high-fidelity traffic simulation tool), four typical freeway segment types—basic sections, weaving zones, on-ramp merging areas, and AV-exclusive lanes—were modeled under diverse traffic demands and AV behavior settings. The findings indicate that, while AVs can improve flow stability in simple environments, their performance may deteriorate in complex merging scenarios without supportive design or behavior coordination. AV-exclusive lanes offer some mitigation when AV share is high. These results underscore that AV integration requires context-specific strategies and cannot be universally applied. Adaptive, behavior-aware traffic management is recommended to support a smooth transition toward mixed autonomy. Full article

With the advancement of autonomous driving technology, transportation systems are inevitably confronted with mixed traffic flows consisting of connected and automated vehicles (CAVs) and human-driven vehicles (HDVs). Current research has predominantly focused on implementing homogeneous control strategies for ramp merging vehicles in such scenarios, which, however, may result in the oversight of specific requirements in fine-grained traffic scenarios. Therefore, a classified cooperative merging strategy is proposed to address the challenges of microscopic decision-making in hybrid traffic environments where HDVs and CAVs coexist. The optimal cooperating vehicle on the mainline is first selected for the target ramp vehicle based on the principle of minimizing time differences. Three merging strategies—joint coordinated control, partial cooperation, and speed limit optimization—are then established according to the pairing type between the cooperating and ramp vehicles. Optimal deceleration and lane-changing decisions are implemented using the average speed change rate within the control area to achieve cooperative merging. Validation via a SUMO-based simulation platform demonstrates that the proposed strategy reduces fuel consumption by 6.32%, NO_x emissions by 9.42%, CO₂ emissions by 9.37%, and total delay by 32.15% compared to uncontrolled merging. These results confirm the effectiveness of the proposed strategy in mitigating energy consumption, emissions, and vehicle delays. Full article

Background: Despite advances in repair techniques, the failure rates of meniscal surgery are still high. The seven most common tear types—horizontal cleavage tears (HCTs), radial tears (RTs), meniscal ramp lesions (MRLs), meniscal root tears (MRTs), longitudinal tears (LTs), bucket-handle tears (BHMTs), and complex meniscal tears (CMTs)—were reviewed. The present retrospective observational study aimed to analyze their characteristics, incidence, treatment approach and failure rates of a consecutive cohort of patients undergoing meniscal arthroscopic repair. Methods: The database of a high-volume meniscal suture center was examined for lesions managed by all-inside, inside-out, outside-in, or transtibial pull-out techniques from January 2018 to September 2022. Demographic (gender, age at surgery, laterality of the affected knee) and intraoperative data (tear type/site, repair technique, and suture number/combination) were collected in order to calculate the failure rates of the cohort and of each tear type and suture technique. Results: Altogether, 636 procedures met our criteria of having at least a 2-year follow-up. The overall failure rate was 1.98%. The most frequent lesions were HCTs (41.98%), with most injuries being in the body/posterior horn (88.52%) of the right knee (56.92%). Treatment predominantly (92.50%) included all-inside sutures. All-inside repair had the highest failure rate (2.98%), followed by inside-out (1.56%) repair (p = 1.0), whereas outside-in and pull-out techniques never failed. Failure rates by lesion included BHMTs (7.27%), HCTs (2.25%), CMTs (1.49%), and LTs (1.25%); RMT, RML, and MRT repair were always successful. Conclusions: Findings at two years suggest that 1–3 all-inside sutures minimize MRL failure, whereas three or more all-inside sutures or combined techniques seem to be effective for HCTs, LTs, and RTs but not BHMTs. Pull-out repair worked best for complete tears/avulsion types of MRTs, whereas all-inside sutures effectively managed partial lesions. Results for CMTs were inconclusive. Full article

This study has established and resolved a new mathematical model of a homogeneous, generalized, magnetothermoelastic half-space with a thermally loaded bounding surface, subjected to ramp-type heating and supported by a solid foundation where these types of mathematical models have been widely used in many sciences, such as geophysics and aerospace. The governing equations are formulated according to the Green–Lindsay theory of generalized thermoelasticity. This work’s uniqueness lies in the examination of Maxwell’s time-fractional equations via the definition of Caputo’s fractional derivative. The Laplace transform method has been used to obtain the solutions promptly. Inversions of the Laplace transform have been computed via Tzou’s iterative approach. The numerical findings are shown in graphs representing the distributions of the temperature increment, stress, strain, displacement, induced electric field, and induced magnetic field. The time-fractional parameter derived from Maxwell’s equations significantly influences all examined functions; however, it does not impact the temperature increase. The time-fractional parameter of Maxwell’s equations functions as a resistor to material deformation, particle motion, and the resulting magnetic field strength. Conversely, it acts as a catalyst for the stress and electric field intensity inside the material. The strength of the main magnetic field considerably influences the mechanical and electromagnetic functions; however, it has a lesser effect on the thermal function. Full article

This study presents a novel mathematical model of a generalized magnetothermoelastic half-space based on the Green–Naghdi theorem, namely type-I and type-III. The half-space surface undergoes ramp-type heating and is positioned on a sturdy base to prevent movement. This research is novel as it employs Caputo’s definition of fractional derivatives within the context of Maxwell’s time-fractional equations. Laplace transform methods are used to obtain the solutions. Tzou’s iterative method has been used to calculate inversions of the Laplace transform. The findings include quantitative answers for temperature increase, strain, displacement, stress, induced magnetic field, and induced electric field distributions. The time-fraction parameter defined by Maxwell’s equation considerably influences all essential mechanical functions, but the thermal functions remain unchanged. In Maxwell’s equations, the time-fractional parameter functions augment the induced electric field inside the material, acting as a resistor to particle motion and the induced magnetic field, while concurrently facilitating the induced electric field. Moreover, the thermal, mechanical, and magnetoelectric waves of Green–Naghdi type-III propagate at a reduced velocity compared to type-I. The fundamental magnetic field substantially influences all examined functions. Full article

Background: The synonymous variant NC_000007.14:g.100373690T>C (rs2405442:T>C) in the Paired Immunoglobulin-like Type 2 Receptor Alpha (PILRA) gene was previously associated with decreased risk for Alzheimer’s disease (AD) in genome-wide association studies, but its biological impact is largely unknown. Objective: We hypothesized that rs2405442:T>C decreases mRNA and protein levels by destroying a ramp of slowly translated codons at the 5′ end of PILRA. Methods: We assessed rs2405442:T>C predicted effects on PILRA through quantitative polymerase chain reactions (qPCRs) and enzyme-linked immunosorbent assays (ELISAs) using Chinese hamster ovary (CHO) cells. RESULTS: Both mRNA (p = 1.9184 × 10⁻¹³) and protein (p = 0.01296) levels significantly decreased in the mutant versus the wildtype in the direction that we predicted based on the destruction of a ramp sequence. Conclusions: We show that rs2405442:T>C alone directly impacts PILRA mRNA and protein expression, and ramp sequences may play a role in regulating AD-associated genes without modifying the protein product. Full article

The Palaeocene Lockhart Formation, a carbonate-rich succession abundant in Larger Benthic Foraminifera, represents a significant potential hydrocarbon reservoir extending throughout the Kohat, Potwar and Hazara basins of Pakistan. This study examines two stratigraphic sections of the Lockhart Formation in the Hazara Basin—Bagran and Karhaki—providing crucial insights into its biostratigraphy and microfacies analysis. The formation comprises medium- to fine-grained limestone with shale intercalations, exhibiting argillaceous to compacted textures. Biostratigraphic analysis revealed a diverse assemblage of Larger Benthic Foraminifera, with 23 species identified across 9 genera, including Miscellanea miscella, Lockhartia haimei, Lockhartia conditi and Ranikothalia sindensis. These fossils indicate deposition within Shallow Benthic Zone (SBZ) 4 during the Late Thanetian, suggesting a dynamic palaeoenvironment. Seven distinct microfacies types were identified: bioclastic mudstone, mixed bioclastic wackestone, miliolidal bioclastic wackestone, foraminiferal wackestone–packstone, foraminiferal wackestone, foraminiferal packstone and bioclastic foraminiferal packstone. These microfacies indicate varied depositional settings, from shallow subtidal and lagoonal to shallow restricted and open marine environments, spanning inner ramp to distal mid-ramp conditions. This research advances our understanding of Late Thanetian depositional environments within the Lockhart Limestone, with implications for regional sedimentology, palaeogeographic reconstruction and reservoir characterisation. Full article

The core subunits of the K_V7.2, K_V7.3, and K_V7.5 channels, encoded by the KCNQ2, KCNQ3, and KCNQ5 genes, are expressed across various cell types and play a key role in generating the M-type K⁺ current (I_K(M)). This current is characterized by an activation threshold at low voltages and displays slow activation and deactivation kinetics. Variations in the amplitude and gating kinetics of I_K(M) can significantly influence membrane excitability. Notably, I_K(M) demonstrates distinct voltage-dependent hysteresis when subjected to prolonged isosceles-triangular ramp pulses. In this review, we explore various small-molecule modulators that can either inhibit or enhance the amplitude of I_K(M), along with their perturbations on its gating kinetics and voltage-dependent hysteresis. The inhibitors of I_K(M) highlighted here include bisoprolol, brivaracetam, cannabidiol, nalbuphine, phenobarbital, and remdesivir. Conversely, compounds such as flupirtine, kynurenic acid, naringenin, QO-58, and solifenacin have been shown to enhance I_K(M). These modulators show potential as pharmacological or therapeutic strategies for treating certain disorders linked to gain-of-function or loss-of-function mutations in M-type K⁺ (K_V7x or KCNQx) channels. Full article

Numerous studies have previously explored the perception of horizontal movements. This includes research on Redirected Walking (RDW). However, the challenge of replicating the sensation of vertical movement has remained a recurring theme. Many conventional methods rely on physically mimicking steps or slopes, which can be hazardous and induce fear. This is especially true when head-mounted displays (HMDs) obstruct the user’s field of vision. Our primary objective was to reproduce the sensation of ascending a slope while traversing a flat surface. This effect is achieved by giving the users the haptic sensation of gripping a tilted handrail similar to those commonly found on ramps or escalators. To achieve this, we developed a walker-type handrail device capable of tilting across a wide range of angles. We induced a cross-modal effect to enhance the perception of walking up a slope. This was achieved by combining haptic feedback from the hardware with an HMD-driven visual simulation of an upward-sloping scene. The results indicated that the condition with tactile presentation significantly alleviated fear and enhanced the sensation of walking uphill compared to the condition without tactile presentation. Full article

The responses of benthic fauna to channel modifications of mountain rivers by low-head barriers are poorly understood. The study aimed (1) to estimate the impact of two different low-head barrier types: concrete sills and block ramps, on Oligochaeta and Trichoptera communities in two small Carpathian rivers (Porębianka and Mszanka) in southern Poland, and (2) to determine changes in these communities in the mountain Porębianka River after 50 years by comparing current data with historical data. Both types of channel modifications led to a transformation from lotic to more lentic habitats. The research shows that habitat conditions and induced bed siltation greatly influenced the studied communities. In both rivers, the taxa richness and dominant taxa of Oligochaeta and Trichoptera were similar, alongside similar species compositions of Trichoptera. However, the river with the lower bed siltation rate had a higher Trichoptera density and a greater diversity in their density among habitats. After 50 years, the taxonomic richness of Oligochaeta and Trichoptera remained similar, unlike the considerable shift in their species compositions. Many species typical of mountain rivers have been replaced by species more tolerant to siltation, characteristic of lowland rivers. The family Tubificidae (Oli-gochaeta) and the genus Hydropsyche (Trichoptera) became dominant in both rivers in the early 2020s. Additionally, the functional feeding group (FFG) of Trichoptera changed considerably. Oligochaeta and Trichoptera communities serve as valuable indicators for moni-toring the environmental changes in these ecosystems. Full article

In the connected and autonomous vehicle (CAV) environment, vehicles with different levels of automation are being deployed on public roads. Most research focuses on traffic flow simulation for a single vehicle type, while there are few studies on the interactions of mixed traffic involving CAVs, autonomous vehicles (AVs), and human-driven vehicles (HDVs). To fill this gap, this study investigates the traffic performance of heterogeneous traffic on multi-lane ring roads and highways with on-ramps. Leveraging the Python and SUMO simulation platform, the JAD strategy is introduced to optimize the dynamic interactions within heterogeneous traffic flow. Various scenarios with different proportions of CAVs, AVs, and HDVs were simulated to assess their impact on traffic efficiency, dynamics, safety, and environmental factors. The findings indicate that traffic efficiency, stability, and environmental impact improve as the share of HDVs declines and the proportion of CAVs and AVs rises. In scenarios with more HDVs, the improvements are minimal. Traffic safety gradually improves as the proportion of CAVs and AVs increases, with significant improvements observed when CAVs account for 40% of vehicles on ring roads and 50% on highways. This study advances the understanding of complex interactions in mixed traffic scenarios and their implications for traffic management. Full article