366 research outputs found
Dynamic Management of Hardware Multi-threading for Network Processors
AbstractIn this paper, we presented a dynamic management mechanism of hardware multi-threading for pipelined hardware multi-threading architecture. And a set of special instructions are provided. In view of the workload and traffic of network are uncertainty, the dynamic multi-threading architecture in this paper can adaptively adjust processor performance according to the workload, and achieve the effective power savings
Analysis of Red-Light Violation Behavior of Pedestrian Two-Stage Crossing at a Signalized Intersection
Studying pedestriansā twice-crossing behavior is of great significance to enhance safety and efficiency for pedestrians at signalized intersections. However, researchers have paid little attention to analyze and model pedestriansā red-light running behavior on a two-stage crossing at signalized intersections. This paper focuses on analyzing the characteristics of pedestrian red-light violation behavior at the two stages, including the time distribution of violation behavior, the consistency of violation behavior, and the violation behavior in group.Ā A goal-oriented and time-driven red-light violation behavior model was proposed for pedestrian two-stage crossing. A video-recording method was used to collect field data, and the results show that pedestrians in the two directions present different red-light violation behaviors in time selection and violation count, as well as, pedestrians in the two stages of a direction present different red-light violation behaviors in time selection. The main reasons leading to the phenomena were analyzed, regarding from peopleās cognitive psychology and visual perception. The results also show that the proposed model is effective in simulating pedestrian red-light violation behavior of twice crossing. This research provides a theoretical basis for optimizing signal timing, improving pedestrian safety and developing user-friendly transportation system
Analysis of Route Choice for Pedestrian Two-Stage Crossing at a Signalized Intersection
Studying pedestriansā twice-crossing behavior is of great significance to enhance safety and efficiency for pedestrians at signalized intersections. However, limited attention has been paid to analyze and model pedestriansā behavior patterns of twice crossing. The purpose of this paper is to determine pedestrians' route choices for twice crossing at a signalized intersection, focusing on the waiting position (to cross the street) and walking route. A goal-oriented and time-driven model was proposed to analyze pedestriansā twice-crossing behavior at signalized intersections, where the two directions have different pedestrian signal timing. A video-recording method was used to collect field data in order to obtain pedestrian preferences in choosing a walking route. It was found that pedestrians in the two directions present different preferences toward walking route, in waiting position, directional change and route type. The results showed that the proposed model is effective in simulating pedestrian route-choice behavior of twice crossing. This research provides a theoretical basis for identifying pedestrian movement intention, optimizing signal timing, and improving pedestrian infrastructure at signalized intersections.
Phonon-Mediated High-Temperature Superconductivity in Few-Hydrogen Metal-Bonded Perovskite up to 54 K under Ambient Pressure
Multi-hydrogen lanthanum hydrides have shown the highest critical temperature
at 250-260 K under 170-200 GPa. However, such high pressure is a great
challenge for sample preparation and practical application. To address this
challenge, we propose a novel design strategy for high- superconductors by
constructing new few-hydrogen metal-bonded perovskite hydrides at ambient
pressure, such as , with better ductility than the well-known
multi-hydrogen, cuprate and iron-based superconductors. Based on the
Migdal-Eliashberg theory, we predict that the structurally stable
has a favorable high up to 54 K under atmospheric pressure, similar to
SmOFeAs.Comment: 6 pages, 4 figure
Feedback between carbon and nitrogen cycles during the Ediacaran Shuram excursion
This research is supported by the National Natural Science Foundation of China (41872032, 41830215, 41930320) and the Chinese ā111ā project (B20011).The middle Ediacaran Period records one of the deepest negative carbonate carbon isotope (Ī“13Ccarb) excursions in Earth history (termed the Shuram excursion). This excursion is argued by many to represent a large perturbation of the global carbon cycle. If true, this event may also have induced significant changes in the nitrogen cycle, because carbon and nitrogen are intimately coupled in the global ocean. However, the response of the nitrogen cycle to the Shuram excursion remains ambiguous. Here, we reported high resolution bulk nitrogen isotope (Ī“15N) and organic carbon isotope (Ī“13Corg) data from the upper Doushantuo Formation in two well-preserved sections (Jiulongwan and Xiangerwan) in South China. The Shuram-equivalent excursion is well developed in both localities, and our results show a synchronous decrease in Ī“15N across the event. This observation is further supported by bootstrapping simulations taking into account all published Ī“15N data from the Doushantuo Formation. Isotopic mass balance calculations suggest that the decrease in Ī“15N during the Shuram excursion is best explained by the reduction of isotopic fractionation associated with water column denitrification (Īµwd) in response to feedbacks between carbon and nitrogen cycling, which were modulated by changes in primary productivity and recycled nutrient elements through remineralization of organic matter. The study presented here thus offers a new perspective for coupled variations in carbon and nitrogen cycles and sheds new light on this critical time in Earth history.Publisher PDFPeer reviewe
Calculation of Stability Limit Displacement of Surrounding Rock of Deep-Buried Soft Rock Tunnel Construction Based on Fuzzy Logic Matching Algorithm
With the continuous development of society and economy, infrastructure construction is expanding on a large scale. The stress concentration after excavation in deep-buried soft rock masses may cause the stress level of the rock mass to exceed the strength of the surrounding rock and form plastic stress, the area where plastic shear slip or plastic flow occurs. Based on the fuzzy logic matching algorithm for the surrounding rock of deep-buried soft rock tunnel construction, this paper analyzes the development law of surrounding rock deformation and supporting force over time in actual construction by establishing elementary function mathematical calculation equations, and tries to construct a set of It is used to determine the actual deep-buried soft rock tunnel surrounding rock stability limit displacement value process. Practical results show that the process based on fuzzy logic matching algorithm can effectively meet the requirements of actual deep-buried soft rock tunnel engineering
- ā¦