Type Synthesis of Self-Alignment Parallel Ankle Rehabilitation Robot with Suitable Passive Degrees of Freedom

The current parallel ankle rehabilitation robot(ARR)suffers from the problem of difficult real-time alignment of the human-robot joint center of rotation,which may lead to secondary injuries to the patient.This study investigates type synthesis of a parallel self-alignment ankle rehabilitation robot(PSAARR)based on the kinematic characteristics of ankle joint rotation center drift from the perspective of introducing"suitable passive degrees of freedom(DOF)"with a suitable number and form.First,the self-alignment principle of parallel ARR was proposed by deriving conditions for transforming a human-robot closed chain(HRCC)formed by an ARR and human body into a kinematic suitable constrained system and introducing conditions of"decoupled"and"less limb".Second,the relationship between the self-alignment principle and actuation wrenches(twists)of PSAARR was analyzed with the velocity Jacobian matrix as a"bridge".Subsequently,the type synthesis conditions of PSAARR were proposed.Third,a PSAARR synthesis method was proposed based on the screw theory and type of PSAARR synthesis conducted.Finally,an HRCC kinematic model was established to verify the self-alignment capability of the PSAARR.In this study,93 types of PSAARR limb structures were synthesized and the self-alignment capability of a human-robot joint axis was verified through kinematic analysis,which provides a theoretical basis for the design of such an ARR.

A review on SRAM-based computing in-memory:Circuits,functions,and applications

Artificial intelligence(AI)processes data-centric applications with minimal effort.However,it poses new challenges to system design in terms of computational speed and energy efficiency.The traditional von Neumann architecture cannot meet the requirements of heavily datacentric applications due to the separation of computation and storage.The emergence of computing inmemory(CIM)is significant in circumventing the von Neumann bottleneck.A commercialized memory architecture,static random-access memory(SRAM),is fast and robust,consumes less power,and is compatible with state-of-the-art technology.This study investigates the research progress of SRAM-based CIM technology in three levels:circuit,function,and application.It also outlines the problems,challenges,and prospects of SRAM-based CIM macros.

Cultivation of aerobic granular sludge in a conventional, continuous flow, completely mixed activated sludge system

Aerobic granules were formed in a conven- tional, continuous flow, completely mixed activated sludge system （CMAS）. The reactor was inoculated with seed sludge containing few filaments and fed with synthetic municipal wastewater. The settling time of the sludge and the average dissolved oxygen （DO） of the reactor were 2 h and 4.2 mg. L 1, respectively. The reactor was agitated by a stirrer, with a speed of 250r·min^-1, to ensure good mixing . The granular sludge had good settleability, and the sludge volume index （SVI） was between 50 and 90 mL ·g ^-1. The laser particle analyzer showed the diameter of the granules to be between 0.18 and 1.25 mm. A scanning electron microscope （SEM） investigation revealed the predominance of sphere-like and rod-like bacteria, and only few filaments grew in the granules. The microbial community structure of the granules was also analyzed by polymerase chain reaction-denaturing gradient gel electro- phoresis （PCR-DGGE）. Sequencing analysis indicated the dominant species were α, β, and γ-Proteobacteria, Bacteroidetes, and Firmicutes. The data from the study suggested that aerobic granules could form, if provided with sufficient number of filaments and high shear force. It was also observed that a high height-to-diameter ratio of the reactor and short settling time were not essential for the formation of aerobic granular sludge.

非政府组织在加强少数民族事务工作中的作用——以欧洲罗姆人非政府组织为例

冷战结束以来,欧洲少数民族事务领域的非政府组织发展迅速,这些组织在与欧洲国际组织和各国政府一道,在推动少数民族事务工作的过程中发挥了重要的作用。其中,罗姆人非政府组织的发展尤其引人注目。它们在影响欧盟少数民族政策、推动罗姆人融入社会,加强对罗姆人的司法救助,引领罗姆人参与政治等方面发挥了重要作用。但由于各方面的原因,它们的发展也存在着一些难以克服的问题,影响力还有待提高。