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Various approaches to mechanical modeling are available in practice to calculate the dynamic response of railway bridges under high-speed traffic, differing significantly in their complexity and accuracy. Very simple models often overestimate the vibrations occurring in reality but are much more computationally efficient and dependent on only a few input parameters than more complex and accurate models. Modeling the high-speed train as a multi-body system can represent the beneficial vehicle-bridge interaction, but it requires knowledge of numerous vehicle parameters, which manufacturers rarely disclose. In contrast, the track-bridge interaction can also be depicted by a simple coupling beam modeling of the structure, requiring only a few input parameters representing the dynamic stiffness and damping of the track. Several calculations on different single-span steel girder bridges demonstrate the influence of different model variants and input parameters on the acceleration results of the structure. Additionally, an approach for determining a dynamic distribution of the train axle loads affecting the bridge depending on the assumed vertical track stiffness is presented.

In this paper, we propose a mesh with a global bus as a multi-computer topology. This structure enhances the communication capability of the mesh and shows that the mesh with a global bus has more salient properties than the mesh, the hypercube, or other variants. These properties includes a small diameter, a relatively small degree, small average distance, suitability for broadcasting, small initial data distribution time, etc. We propose a dynamic load distribution algorithm to utilize the enhanced communication capability of the mesh with a global bus. Also, asynchronous bus control and arbitration logics are designed to support the proposed algorithm efficiently. It has been shown through simulation that the proposed dynamic load distribution is superior to the Receiver Initiated Diffusion method, previously known as the best to-date. The proposed algorithm shows better total task execution time and better processor utilization with a smaller number of task migrations.

In this work, we study the effects of scale-free topology and congestion on load distribution. Congestion effect can be described by link cost functions, which map link flows into travel times. Two different kinds of link's practical capacity (it is similar to link's capacity for transport) which is a parameter in link cost functions, i.e., uniform case and nonuniform case, are investigated. After introducing the effect of congestion, load distribution is typically discussed in Barábasi–Albert and Goh scale-free networks. In the uniform case, for Barábasi–Albert scale-free networks, we recover a power-law behavior for load distribution with a larger exponent, as compared with the distribution of betweenness centrality; for Goh scale-free networks, we also recover a power-law behavior and its exponent approaches to the exponent of degree distribution. While in the nonuniform case, the power-law behavior for load distribution may not always be conserved in both Barábasi–Albert and Goh scale-free networks. That is to say, different kinds of load distributions are obtained under different conditions. It may shed some light to study traffic dynamics on scale-free networks.

Traffic demand is one of the most important factors to affect the traffic flow pattern or load distribution in congested networks. In this paper, we investigate the load distributions and relations between the load and degree of the node for different traffic demands in scale-free networks. Different kinds of load distributions are obtained under different traffic demands. Furthermore, the impact of link capacity on load distribution in congested scale-free networks is also discussed.

With the rotating-arm axis box as the research object, we established a test method in the original place of damage of the axis box that can reproduce the suspension parameter conditions of the bogie frame. First, this method establishes a real axis box mechanical model based on the suspension parameters of the axis box assembly conditions and calculates the load distribution relationship of the axis box through this model. Second, through a comparison of test data under different tooling conditions, it was verified that the distribution relationship had a great influence on the strength evaluation of the axis box body. Then, the single-axis box test method was simulated and optimized to determine the distribution of test loads and constraint conditions. The calculation results better restored the axis box test data under in situ conditions and derived a single-axis box test method with high accuracy. The lowest damage coverage was 1.01. The mechanical modeling and test optimization approach not only improves damage-based life assessment but also tunes up the efficiency of axis box testing.

As third and fourth generation cellular/wireless networks evolve, operators must learn to efficiently manage diverse services, and multiple networks consisting of varying technologies, cell sizes, and frequency bands. Architectural studies on integrated heterogeneous networks suggest that vertical handovers can be used to increase network efficiency. We propose that carefully-controlled load distribution can also promote Quality of Service (QoS) goals for the diverse services. This study compares session overflow and session placement algorithms in order to determine their effects on efficiency and QoS.

A novel Interconnection Network Architecture is proposed for integrating tightly coupled Distributed Systems. It allows the implementation of Service Address Routing(SAR): network communications between components are based on the "name" of requested services. It is a client-server communications model, and optionally includes the traditional physical addressing schemes. This enhanced network architecture registers the capabilities of the components attached to its ports and directs service requests to appropriate server nodes. The Network can perform Resource Allocation by placing services in nodes that can support them. Load Distribution is achieved by binding requests to adequate servers with enough free resources. Furthermore, SAR effects a simple, yet efficient and transparent resource discovery mechanism by means of a distributed content-addressable search at each network port. A scalable implementation for computer clusters is proposed which uses the Least-Common-Ancestor Networks (LCANs) as the model for the hierarchical interconnect. At the end of this work, an analysis based on theoretical examination and experimental testing is carried out; scalability and cost-effectiveness of the proposed Service-Address-Routed Least-Common-Ancestor Networks are thus examined.

In the process of aircraft structural design, the aerodynamic load and inertial load need to be distributed from single loading points to distributed finite element (FE) nodes before strength analysis. The most commonly used loading distribution method is a Multi-Point Arrangement (MPA) method, which introduces a one-dimensional Lagrange multiplier based on the principle of minimum deformation energy, and simplifies the special-shaped 3D surface in aircraft structure to a plane. However, the actual aircraft structure contains a large number of special-shaped surfaces, and the MPA method cannot accurately distribute the loads on these complex special-shaped surfaces, affecting the accuracy of strength analysis. This paper developed a new 3D load distribution method based on multi-dimensional Lagrange multipliers (MDLM), which can simultaneously achieve an efficient and accurate distribution of surface aerodynamic loads and inertial loads in all directions. Typical numerical cases showed that when an aircraft structure model is a plane, this MDLM method converges to the traditional MPA method. For 3D special-shaped surfaces, the average error of this MDLM method is 0.77–2.28%, which is significantly smaller than the average error of the traditional MPA method (3.30–7.40%).

Valuable energy resources of sensor network should be utilized wisely to prolong network's lifetime. Clustering technique helps wireless sensor network (WSN) to enhance its lifetime by reducing energy consumption on every individual sensor node in the network. In multi-hop data forwarding model, difference in energy consumption among cluster heads (HS) causes hot-spot problem in the network. While data is being transferred, the CH close to base station are burdened with heavy relay traffic from several data routes and tend to die early. Unequal clustering avoids this hot-spot problem by establishing different sized clusters at various levels in the network. Since unequal clustering technique does not control number of CHs it creates, it forms huge number of clusters in the network. This increases hop count between source and destination, and leads to impose more over head on each data forwarding route in the network. Also, rapid variation in cluster size causes imbalance in energy dissipation among clustered nodes in the network. This uneven energy consumption influences network performance and lifetime. In this paper, we present an energy-efficient hybrid clustering mechanism for wireless sensor network using equal and unequal clustering techniques to create limited number of clusters in varied sizes at various level of the network. This avoids hot-spot problem with minimum hop count between the source and destination and achieves uniform energy dissipation between intra- and inter-cluster communication. Simulation results show that the proposed clustering mechanism balances the energy consumption among clusters with its hybrid cluster formation mechanism and elevates sensor network lifetime.

this paper proposes a novel shuffle turning method for a humanoid robot by controlling load distribution of each sole. Conventionally, turning motion of a humanoid robot is performed by repeating of stepping the feet. However the motion is inefficient and time consuming, In our proposed methods, the feet are slipped on the floor without stepping. To minimize variation of the turning angle due to the friction variation of the floor, the directions of the feet are changed following a predetermined trajectory and the load distributions of the soles are controlled to be nonuniform. Experiments with the humanoid robot HOAP-2 were conducted to verify the validity of the proposed method.