Optimization Scheme of Large Passenger Flow in Huoying Station,Line 13 of Beijing Subway System

This paper focuses on the distribution of passenger flow in Huoying Station,Line 13 of Beijing subway system.The transformation measures taken by Line 13 since operation are firstly summarized.Then the authors elaborate the facilities and equipment of this station,especially the node layout and passenger flow field.An optimization scheme is proposed to rapidly distribute the passenger flow in Huoying Station by adjusting the operation time of the escalator in the direction of Xizhimen.The authors adopt Queuing theory and Anylogic simulation software to simulate the original and the optimized schemes of Huoying Station to distribute the passenger flow.The results of the simulation indicate that the optimized scheme could effectively alleviate the traffic congestion in the hall of Huoying Station,and the pedestrian density in other places of the hall is lowered;passengers could move freely in the hall and no new congestion points would form.The rationality of the scheme is thus proved.

The Performance of a Novel Latching-Type Electromagnetic Actuator for Single-Port Laparoscopic Surgery

This paper reports on the performance evaluation of a novel latching-type electromagnetic actuator which is designed to be embedded at selected joints along single-port laparoscopic surgical instruments (SLS). The aim of this actuator is to allow these instruments to become articulated with a push of a button in order to provide the optimum angulation required during SLS operations. This new actuator is comprised of electromagnetic coil elements, soft magnetic frames and a permanent magnet. Unlike conventional electromagnetic actuators, latching-type electromagnetic actuators could maintain their positions at either end of the actuation stroke without any power application requirement. In the current design, magnetic attraction forces initiated between the permanent magnet and the magnetic frame are utilised to lock the position of the actuator whilst a certain angulation position of the actuator is achieved as a result of the magnetic repulsion forces established between the permanent magnet and the coil elements. The performance of the new actuator in terms of the output force, maximum angulation and patient’s safety, was evaluated experimentally and the results were found to compare well with those acquired numerically using finite element methods. This actuator was seen to exhibit sufficient actuation forces and hence, it was capable of providing adaptable angulation characteristics for SLS tools. Finally, thermal evaluation of the actuator’s operation was conducted, which was found to be within safety limits specified by clinicians.

Effect of calcination temperature on the pozzolanic activity of maize straw stem ash treated with portlandite solution

The effect of calcination temperature on the pozzolanic activity of maize straw stem ash(MSSA)was evaluated.The MSSA samples calcined at temperature values of 500,700,and 850℃ were dissolved in portlandite solution for 6 h,thereby obtaining residual samples.The MSSA and MSSA residual samples were analyzed using Fourier transform infrared spectroscopy,X-ray powder diffraction scanning electron microscopy,and X-ray photoelectron spectroscopy to determine vibration bonds,minerals,microstructures,and Si 2p transformation behavior.The conductivity,pH value,and loss of conductivity with dissolving time of the MSSA-portlandite mixed solution were also determined.The main oxide composition of MSSA was silica and potassium oxide.The dissolution of the Si^(4+) content of MSSA at 500℃ was higher than those of the other calcination temperatures.The conductivity and loss of conductivity of MSSA at 700℃ were higher than those of the other calcination temperatures at a particular dissolving time due to the higher KCl content in MSSA at 700℃.C-S-H was easily identified in MSSA samples using X-ray powder diffraction,and small cubic and nearly spherical particles of C-S-H were found in the MSSA residual samples.In conclusion,the optimum calcination temperature of MSSA having the best pozzolanic activity is 500℃,but excessive agglomeration must be prevented.

Hippo-YAP/TAZ signaling in osteogenesis and macrophage polarization:Therapeutic implications in bone defect repair

Bone defects caused by diseases or surgery are a common clinical problem.Researchers are devoted to finding biological mechanisms that accelerate bone defect repair,which is a complex and continuous process controlled by many factors.As members of transcriptional costimulatory molecules,Yes-associated protein(YAP)and transcriptional co-activator with PDZ-binding motif(TAZ)play an important regulatory role in osteogenesis,and they affect cell function by regulating the expression of osteogenic genes in osteogenesis-related cells.Macrophages are an important group of cells whose function is regulated by YAP/TAZ.Currently,the relationship between YAP/TAZ and macrophage polarization has attracted increasing attention.In bone tissue,YAP/TAZ can realize diverse osteogenic regulation by mediating macrophage polarization.Macrophages polarize into M1 and M2 phenotypes under different stimuli.M1 macrophages dominate the inflammatory response by releasing a number of inflammatory mediators in the early phase of bone defect repair,while massive aggregation of M2 macrophages is beneficial for inflammation resolution and tissue repair,as they secrete many anti-inflammatory and osteogenesis-related cytokines.The mechanism of YAP/TAZ-mediated macrophage polarization during osteogenesis warrants further study and it is likely to be a promising strategy for bone defect repair.In this article,we review the effect of Hippo-YAP/TAZ signaling and macrophage polarization on bone defect repair,and highlight the regulation of macrophage polarization by YAP/TAZ.

Modeling and Experimental Evaluation of a Bionic Soft Pneumatic Gripper with Joint Actuator

The pneumatic gripper in industrial applications has the advantages of structure simplicity and great adaptability,but its gripping power is usually limited due to the low modulus of soft materials.To address this problem,a novel bionic pneumatic gripper inspired by spider legs is proposed.The design has two pairs of symmetrical fingers,each finger consists of two pneumatic actuated joints,two rigid links and one pneumatic soft pad.The rigid link connects the pneumatic chamber which is enclosed in a retractable shell to increase the actuation pressure and the gripping force.The compressibility and elasticity of the soft joint and pad enable the gripper to grasp fragile objects without damage.The modeling of the bionic gripper is developed,and the parameters of the joint actuators are optimized accordingly.The prototype is manufactured and tested with the developed experimental platform,where the gripping force,flexibility and adaptability are evaluated.The results indicate that the designed gripper can grasp irregular and fragile items in sizes from 40 to 140 mm without damage,and the lifting weight is up to 15 N.

Behaviour and mechanisms of molecular vibrations induced by a pulsed voltage in a silicone elastomer used for device encapsulation

Silicone elastomers are widely used to encapsulate power electronic devices.However,such devices may be subjected to square‐wave pulsed voltages with a high rate of change,which can create significant challenges for encapsulation insulation.In this article,the molecular vibration of silicon elastomer at the edge of pulsed electric field is studied.Firstly,the relationship between the intensity of molecular vibration and the parameters of pulsed electric field is explored.The experimental results show that the amplitude of the vibrations decreases as the pulse‐edge time increases,and it increases linearly as the pulseedge slope increases.Furthermore,the amplitude of the vibrations is proportional to the square of the amplitude of the pulsed electric field,and it increases as the space charge density increases.Then,the force analysis of charged molecule at the pulse edges is calculated,and the theoretical change law of molecular vibration intensity with pulse edge slope is deduced.Comparing the theoretical results with the experimental results,it is found that they are highly consistent.Finally,electrically induced mechanical stress caused by molecular vibration was shown to be an important factor in insulation failure.

Sodium tungsten bronze(Na_(x)WO_(3))-doped near-infrared-shielding bulk glasses for energy-saving applications

Tungsten bronze coatings and films have attracted global attention for their applications in near-infrared(NIR)-shielding windows.However,they are unstable in strong ultraviolet,humid heat,alkaline and/or oxidizing environments and are difficult to be coated on glass surfaces with complex shape.Here,we address these limitations by doping sodium tungsten bronze(Na_(x)WO_(3))into bulk glasses using a simple glass melting method.X-ray diffraction,Raman spectroscopy,X-ray photoelectron spectroscopy,TEM and SEM-EDS characterization confirmed the presence of sodium tungsten bronze(Na_(x)WO_(3))functional units inside the 34SiO_(2)-38B_(2)O_(3)-28NaF glass matrix.Because the functional units are well protected by the glass matrix,the fabricated glasses are stable under hot,humid,oxidizing conditions,as well as under ambient conditions,with no change after 360 days.The NIR-shielding performance of these glasses can be adjusted to as high as 100%by varying WO_(x)concentration(2-8 mol%)and quenching temperature(1000-1400℃).With a content of 6 mol%WO_(x)and a quenching temperature of 1000℃,the bulk glass shows 63%transmission of visible light and only 11%transmission of NIR light at 1100 nm.Thermal insulation experiments show that the NIR-shielding performance of the glasses are far superior to commercial soda lime window glass or indium-doped tin oxide(ITO)glass,and comparable to cesium tungsten bronze coated glass.The novel bulk glasses have higher stability,simpler processing,and can be easily made into complex shapes,making them excellent alternative materials for energy-saving glasses.