HX_D2C型电力机车转向架

介绍了由大同电力机车有限责任公司自主研发、设计的HXD2C型交流传动货运电力机车转向架的主要技术参数及结构特点,该转向架消化、吸收了欧洲货运机车转向架的技术。

Compound structure analysis of a new chaotic system

This paper analyzes the compound attractor structure of a new three-dimensional autonomous chaotic system. First, it is found that there exist five equilibria in the chaotic system, and the stabilities of these equilibria are discussed under a constant scalar control input parameter m. Secondly, the trajectories of the attractors on a y-z plane are examined, the reasons why these trajectories can exist or disappear are also described. Finally, the forming procedure of the different scrolls chaotic attractor is explored by computer simulations when the parameter m is varied. It is shown that the new chaotic attractor has a compound structure, it can evolve to other three-dimensional autonomous chaotic systems. The results of theoretical analysis and simulation are helpful for better understanding of other similar chaotic systems.

The Morphology and Structure of GABAergic Neurons in BARREL and VPM

To understand the structure of GABAergic neurons in the VMP and ＂barrel＂, the distribution of GABAergic neurons in the two areas were studied through immunohistochemistry and Laser Scanning Confocal Microscope. The results show that the distribution of GABAergic neurons in VMP and barrel are different, and the coding of information transmission in the two areas are also dissimilar; GABAergic neurons mainly distribute among the lines asymmetrically in VMP, the somata, dendrite and axon of GABAergic neurons are restricted in the ＂barrel＂, rarely having synaptic connections with other ＂barrel＂ around. Therefore, VMP and barrel may have different roles in transmission and on processing of informatiton.

Optimizing Earth Allocation for Rock-Fill Dam Construction

An optimal allocation of earth is of great significance to reduce the project cost and duration in the construction of rock-fill dams. The earth allocation is a dynamic system affected by various time-space constraints. Based on previous studies, a new method of optimizing this dynamic system as a static one is presented. In order to build a generalized and flexible model of the problem, some man-made constraints were investigated in building the mathematic model. Linear programming and simplex method are introduced to solve the optimization problem of earth allocation. A case study in a large-scale rock-fill dam construction project is presented to demonstrate the proposed method and its successful application shows the feasibility and effectiveness of the method.

Cristobal Balenciaga服装作品设计风格的研究

时尚舞台瞬息万变,后起之秀层出不穷,并不乏创新前卫的设计。但潮流易逝,经典永恒,新一代设计师在激流勇进的同时也应该时刻保持谦逊之心致敬经典。20世纪时装业达到空前盛世,涌现了一批时装巨匠,他们的作品放至当前以至未来都值得设计师们去专研学习。

Structural Design of Fiumara d＇Arte Land Art Works

Fiumara d＇arte is an open-air museum of sculpture and contemporary art. Among the art-works of Fiumara d＇arte, the Pyramid is the last one in order of time. It is a monumental sculpture made of COR-TEN steel, by the artist Mauro Staccioli and it is located on one specific point of the 38th parallel of latitude, on a hill of the northern mountains of Sicily. In this study the architectural and engineering features of land art-works built in this particular plein-air park are examined and discussed. After a general description of Fiumara d＇Arte and its significance in the territory, the case of the Pyramid on the 38th parallel is focalized and a discussion of its architectural, artistic and environmental values is reported. Moreover the structural implications in its design and construction are explained, while the worst effects of external actions are underlined by showing the results of the analysis performed on a finite element model of the whole structure.

The Structure of the Optimal Solution Set on the Shortest Paths for Networks

Abstract： The shortest path problem in a network G is to find shortest paths between some specified source vertices and terminal vertices when the lengths of edges are given. The structure of the optimal solutions set on the shortest paths is studied in this paper. First, the conditions of having unique shortest path between two distinguished vertices 8 and t in a network G are discussed; Second, the structural properties of 2-transformation ^-G graph G on the shortest-paths for G are presented heavily.

Meshless Local Discontinuous Petrov-Galerkin Method with Application to Blasting Problems

A meshiess local discontinuous Petrov-Galerkin （MLDPG） method based on the local symmetric weak form （LSWF） is presented with the application to blasting problems. The derivation is similar to that of mesh-based Runge-Kutta Discontinuous Galerkin （RKDG） method. The solutions are reproduced in a set of overlapped spherical sub-domains, and the test functions are employed from a partition of unity of the local basis functions. There is no need of any traditional nonoverlapping mesh either for local approximation purpose or for Galerkin integration purpose in the presented method. The resulting MLDPG method is a meshless, stable, high-order accurate and highly parallelizable scheme which inherits both the advantages of RKDG and meshless method （MM）, and it can handle the problems with extremely complicated physics and geometries easily. Three numerical examples of the one-dimensional Sod shock-tube problem, the blast-wave problem and the Woodward-Colella interacting shock wave problem are given. All the numerical results are in good agreement with the closed solutions. The higher-order MLDPG schemes can reproduce more accurate solution than the lower-order schemes.

Architecture Singularity Analysis of 4-U■S/U■U 5-DOF Parallel Mechanism

Architecture singularity of a parallel mechanism with five degrees of freedom (DOF) is analyzed. Such mechanism consists of a movable platform connected to the base by five active limbs. Four of them are identical 6-DOF limbs and the last one has the same DOF as the specified DOF of the movable platform. Based on the kinematics analysis, two categories of architecture singularities for such mechanism are proposed. Then the sufficient condition for each singularity is researched. Results show that the mechanism is singular when it employs each category of the proposed architecture, provided that it satisfies the corresponding sufficient condition. It can be concluded that the proposed two categories of architecture singularities should be avoided with the following dimensional synthesis of such mechanism.

Theoretical Analysis and Simulation of Jacking Procedure of Pantadome System

In order to obtain the principle of Pantadome lifting process and make theoretical foundation for practical applications, the core idea of Pantadome was introduced, which is to make a structure become a mechanism by temporarily removing some members during the process of construction.The Abstract motion model was built. By determining the change of the coordinates of the hinge joint and that of each point of the structure, simulative analysis of the mechanical motion of Pantadome was realized. Then general program that simulates the lifting process of Pantadome was developed based on AutoCAD environment by Auto Lisp language. By completing the theoretical analysis of the lifting process of Pantadome, three-dimensional simulation of the lifting process of Pantadome was realized. And it is successfully applied to bidding work of practical engineering.

浅议挤出机种类

介绍了各类型的挤出机技术性能、结构特点和应用的范围。

Spin-Dependent Electron Properties of a Triple-Terminal Quantum Dot Structure

Electron transport properties of a triple-terminal Aharonov-Bohm interferometer are theoretically studied.By applying a Rashba spin-orbit coupling to a quantum dot locally, we find that remarkable spin polarization comesabout in the electron transport process with tuning the structure parameters, i.e., the magnetic flux or quantum dotlevels. When the quantum dot levels are aligned with the Fermi level, there only appear spin polarization in thisstructure by the presence of an appropriate magnetic flux. However, in absence of magnetic flux spin polarization andspin separation can be simultaneously realized with the adjustment of quantum dot levels, namely, an incident electronfrom one terminal can select a specific terminal to depart from the quantum dots according to its spin state.

Investigation of Combination Characteristic of Damage Location and Intensity in Arch Using Wavelet Coefficient

Arch is a typical complex structure comparing with beam and plate in bridge system. This paper investigates the damage characteristic combining the crack location with the crack intensity in arch. Initially, the first four displacement modes of intact and different damaged arch are simulated and the displacement mode changes are obtained. Next, the wavelet transformation is applied to the displacement mode changes in arch and wavelet coefficients at damage loci are picked. Finally, the damage index including damage location and damage intensity in arch is provided and plotted. The results show that wavelet coefficient module maximum of mode changes can be the damage indicator and is influenced by damage location and damage intensity. The damage indicator is proportional to the damage intensity and present monotonic trend according to damage location which depend on the mode order. At the same time, the large modulus maximum corresponds to small damage combination of location and intensity in the first four modes.

Analyzing the Corrosion Wastage over Some of the Bulk Carriers＇ Member Locations

In this paper, well-known and structured Monte Carlo simulation technique has been employed in predicting the amounts of the corrosion wastage over some bulk carriers＇ structural elements in different points of time during their exploitation life. As a base for the realization of the simulations, the appropriate statistical data collected over the group of ten bulk carriers have been used. Both longitudinal and transversal ships＇ hull structural elements have been taken into the consideration. Due to some experts＇ knowledge in this domain, the critical hull zones are identified and certain interventions are done in the pre-processing of the input data to the Monte Carlo simulations, all with the aim of achieving better convergence between simulation results and the experts＇ expectations in this field.

Advanced carbon materials for flexible and wearable sensors

Flexible and wearable sensors have drawn ex-tensive concern due to their wide potential applications inwearable electronics and intelligent robots. Flexible sensorswith high sensRivity, good flexibility, and excellent stabilityare highly desirable for monitoring human biomedical signals,movements and the environment. The active materials and thedevice structures are the keys to achieve high performance.Carbon nanomaterials, including carbon nanotubes （CNTs）,graphene, carbon black and carbon nanofibers, are one of themost commonly used active materials for the fabrication ofhigh-performance flexible sensors due to their superiorproperties. Especially, CNTs and graphene can be assembledinto various multi-scaled macroscopic structures, includingone dimensional fibers, two dimensional films and three di-mensional architectures, endowing the facile design of flexiblesensors for wide practical applications. In addition, the hybridstructured carbon materials derived from natural bio-mate-rials also showed a bright prospect for applications in flexiblesensors. This review provides a comprehensive presentation offlexible and wearable sensors based on the above variouscarbon materials. Following a brief introduction of flexiblesensors and carbon materials, the fundamentals of typicalflexible sensors, such as strain sensors, pressure sensors,temperature sensors and humidity sensors, are presented.Then, the latest progress of flexible sensors based on carbonmaterials, including the fabrication processes, performanceand applications, are summarized. Finally, the remainingmajor challenges of carbon-based flexible electronics are dis-cussed and the future research directions are proposed.