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Eco-driving for trains has traditionally focused on minimizing mechanical energy consumption at wheels, while completely ignoring traction chain losses that are rather significant. This article presents a computationally efficient approach to minimize the total electrical energy consumption from traction substations (TS). After a nonlinear and non-convex program is formulated in time domain, a nonlinear and non-convex program is formulated in space domain to overcome the drawbacks of the model in time domain. By convex modeling steps, the non-convex program in space domain is reformulated as a convex program that can be efficiently solved. To further reduce computational effort, a real-time iteration sequential quadratic programming (SQP) algorithm is proposed to solve the convex program in a model predictive control framework. Numerical results indicate that the proposed SQP method yields a near-optimal solution with high computational efficiency. Compared to a traditional mechanical energy consumption model, a TS-to-traction energy efficiency can be improved.

The overspeed protection, smooth driving, punctuality, and energy efficiency of freight trains largely depend on their trajectory optimization. This paper proposes a multi-objective optimization model, which maximizes the weighted sum of energy efficiency, punctuality, and driving smoothness. Model constraints systematically cover many practical conditions, including varying line resistance, overspeed protection, discrete neutral zones, and nonlinear traction and electric braking characteristics. Electric braking and pneumatic braking are distinguished in the freight train model, and the utilization of feedback braking energy is also considered. By nonlinear approximation, the proposed multi-objective optimization model is solved by the quadratic programming (QP) algorithm, and optimized trajectories are obtained. Numerical simulation demonstrates the correctness and effectiveness of the proposed method. Comparisons with two actual trials show that the energy efficiency and driving smoothness of the proposed method are better than that of the drivers’ operation with the same journey time. In addition, the algorithm has a short computation time, which has the potential to be integrated for on-board devices such as the driver advisory system (DAS).

Lithium ore (mineralized) bodies in the area A of central Yunnan Province belong to a sedimentary-type, which are controlled by stratum. The studied ore (mineralized) body mainly occurs in the Middle Permian Liangshan Formation. This work described the morphology, structures, main ore types and geochemical characteristics of this ore body in detail, and discussed the ore-forming material source, occurrence state of lithium and the formation mechanism of lithium ores to clarify the prospecting marks. In the further exploration, comprehensive evaluation of the lithium resources of known bauxite ore bodies in central Yunnan Province should be strengthened, and the exploration of hidden lithium ore bodies should be intensified in order to discover more large and super-large lithium orebodies, which will fill the gap of the national demand for lithium resources, and promote the national defense construction and new energy industry development.

The multi-physics instrument (MPI) is the first user cooperative instrument at the China Spallation Neutron Source (CSNS). It was designed to explore the structures of complex materials at multiple scales based on the neutron total scattering technique. This imposes the requirements for the detector, including a high detection efficiency to reduce the measurement time and a large solid angle coverage to cover a wide range of momentum transfers. To satisfy these demands, a large-area array of 3He-filled linear position-sensitive detectors (LPSDs) was constructed, each with a diameter of 1 inch and pressure of 20 atm. It uses an orbicular layout of the detector and an eight-pack module design for the arrangement of 3He LPSDs, covering a range of scattering angles from 3° to 170° with a total detector area of approximately 7 m2. The detector works in air, which is separated from the vacuum environment to facilitate installation and maintenance. The characteristics of the MPI detector were investigated through Monte Carlo (MC) simulations using Geant4 and experimental measurements. The results suggest that the detectors are highly efficient in the wavelength range of the MPI, and an efficiency over 25% is achievable for above 0.1 Å neutrons. A minimal position resolution of 6.4 mm full width at half maximum (FWHM) along the tube length was achieved at a working voltage of 2200 V, and a deviation below 2 mm between the real and measured positions was attained in the beam experiment. The detector module exhibited good consistency and an excellent counting rate capacity of up to 80 kHz, which satisfied the requirements of experiments with a high event rate. Observations of its operation over the past year have shown that the detector works steadily in sample experiments, which allows the MPI to serve the user program successfully.

The T-shaped radial spoke (RS) is a protein complex attached to the A microtubule of the outer doublet microtubules, and it extends toward the central pair (CP). It modulates the beat frequency, amplitude, and waveform of the flagella and cilia by serving as a mechanochemical signal transducer between the CP and dyneins. In humans, RS defects cause primary ciliary dyskinesia, but the structural components of triple RSs (RS1, RS2, and RS3) in mammals remain to be elucidated in detail. Here, we introduce a mouse model that lacked the entire RS1 in sperm flagella, due to the deletion of Iqub, while the tracheal cilia possessed intact triple RSs. Furthermore, the absence of IQUB only resulted in male infertility, owing to the sperm motility defect. Based on the mouse model, the RS1 compositions are identified in sperm flagella. In summary, this study elucidates the RS1 components and function in mammalian flagella.

Aluminum (Al) and Copper (Cu) have been used in graded density impactors. Al-Cu composites with different compositions have been prepared by hot pressing sintering. Intermetallic compounds were produced when the temperature was above 723 K, while they can’t be found at the temperature of 723 K. The relative density of Al-Cu composites from pure Al to pure Cu consolidated at 723K all exceeded 98.5%. The optimum sintering conditions were then determined to sintering temperature of 723 K, uniaxial pressure of 100 MPa, and duration time of 2 h. Al and Cu were mixed homogeneously and well compacted, and no obvious pores were found. The thickness of diffusion layer between Al and Cu was very thin, only about 0.6 μm. The wave impedance values increased almost linearly from 16.98×106 to 40.66×106 kg/m2·s with increasing Cu content in Al-Cu composite from 0 to 100 vol.%, which was well consistence with the values calculated according to the rule of mixtures. The elastic modulus of different compositions matched well with the theoretical model of Voigt and Reuss. Highly densified Al-Cu composites without intermetallic compounds were successfully prepared using hot-pressure sintering, which was the basis of fabricating Al-Cu system graded density impactors.

The article mainly introduces the design and application of a small power brushless DC motor drive control system circuit, describes the special control function of the gate circuit chip, gives a typical application circuit, and explains.

To realize the target of having a precise feature size measurement of multihole sheet metal part, this paper based on HALCON, first calibrates the camera with HALCON's calibration assistant. After acquiring the image of the multihole sheet metal part, the image coordinates of the center of fitting ellipse and the length of the long and short half shaft (pixel unit) can be gotten by proceeding a series of operations like thresholding, subpixel-precise contour extraction, fitting ellipses and so on. At last, the point coordinates in image are transformed into the plane Z=0 of the world coordinate system through translation and rotation, and the value of each feature size of the sheet metal part can be calculated.

This paper utilized an intelligent vehicle model for the “Freescale” Cup National College Students' Intelligent Vehicle competition as the main study object. Under the prerequisite of adopting the same control procedures and algorithms, the mechanical structures and its parameters of the model vehicle which influence the running performance, such as front wheel alignment, steering mechanism and rear wheel deceleration mechanism are optimally designed and adjusted .It has been proved that the scheme induced the model vehicle driving fast and stable on the path-complex track and thus to achieve reasonable effects.

Such as the canonical equation of force method’s free terms and coefficients are different from the primary structures, can obtain by the internal forces of the primary structure. This paper demonstrates the correctness and rationality, as well as the applicable range from theory.And the creation of a new method to solve statically indeterminate structure, said this method is the multiple primary structure of force method.

The analysis rule of geometry composition analysis in building structure must rely on geometry theory, while the traditional Euclidean geometry theory can not solve some building structures problems of the geometry components. This problem can be solved in the use of projective geometry theory. In this paper we introduce the proof of projective geometry in the geometry composition analysis and we discuss the application of this theory.

According to the force method of solving of statically indeterminate structure is requirements of the primary structure, the primary structure can be a statically determinate structure also be a statically indeterminate structure. The higher degrees statically indeterminate problems, broken down into multi-layer lower degrees statically indeterminate problems, successive to solve, so time after time using lower degrees or even one degree force method typical equation, the less the solution or do not need to solve simultaneous equations, and solving the higher degrees statically indeterminate structure. On this basis, it can easily statically indeterminate structure with other solution methods in combination, to improve operational efficiency.

In a principle of kinematics, when a rigid body is motion in a plane, and the fixed plane only the presence of a speed zero point -- the instantaneous center of velocity. In the mechanism of two rigid bodies be connected by two parallel connection links, why can the continuous relative translation? Where is the instantaneous center of velocity? ... ... The traditional Euclidean geometry theory can’t explain these phenomenon, must use projective geometry theory to solve. The actual motion of the mechanism is disproof in Euclidean geometry principle limitation. This paper introduces the required in projective geometry basic proof of principle, and applied to a specific problem.

From the graphics section moment of inertia rotation axis formula can make a geometric figure (Moment of inertia circle), and thus may calculate inertia axis rotation calculation problem, called the graphics section moment of inertia rotation axis calculation diagram method. This method can directly answer some questions to be very difficult answered by analytic method. Moment of inertia circle and the stress circle is in the form of very close, for the mastery of stress circle to compute, grasp the moment of inertia circle is very convenient.

The bearing capacities of one-way reinforced concrete beams with elastic supports are investigated in this paper. According to the nonlinear characteristics of the beams, the basic equations based on plastic theory of concrete are derived by considering the in-plane force effects that aroused by the constraints of supports when the beams deforming. It is indicated that the calculation results are in good agreement with experimental datum, and the influences of different supports on the bearing capacities of the beams are quantitatively given for the first time.

This event-related functional MRI study examined the neural correlates for Chinese writing, by comparing the writing of logographic characters and that of pinyin, a phonetic notation system for Chinese characters. The temporal profile of the activations indicated that the middle frontal gyrus, superior parietal lobule, and posterior inferior temporal gyrus reflected more central processes for writing. Although pinyin writing elicited greater activity overall than character writing, the critical finding is that the two types of symbols recruited essentially the same brain regions. The results were compared with studies in Japanese showing dissociation between logographic kanji and phonetic kana writing and frequency of use was suggested to be an important factor in accounting for result differences across the two writing systems.