Robotic Walker for Slope Mobility Assistance with Active-Passive Hybrid Actuator

Walking assistance can be realized by active and passive robotic walkers when their users walk on even roads.However,fast signal processing and real-time control are necessary for active robotic walkers when the users walk on slopes,while assistive forces cannot be provided by passive robotic walkers when the users walk uphill.A robotic walker with an active-passive hybrid actuator(APHA)was developed in this study.The APHA,which consists of a rotary magnetorheological(MR)brake and a DC motor,can provide mobility assistance to users walking both uphill and downhill via the cooperative operation of the MR brake and DC motor.The rotary MR brake was designed with a T-shaped configuration,and the system was optimized to minimize the brake volume.Prototypes of the APHA and robotic walker were constructed.A control algorithm for the robotic walker was developed based on the characteristics of the APHA and the structure of the robotic walker.The mechanical properties of the APHA were characterized,and experiments were conducted to evaluate the mobility assistance supplied by the robotic walker on different roads.The results show that the APHA can meet the requirements of the robotic walker,and suitable assistive forces can be provided by the robotic walker,which has a simple mechanical structure and control method.

Conducting the Task-based Approach With Context Aware Mobile Situated Learning on Learning English for College Students＇ Learning Performance

Learning English with specific purpose （ESP） initiatives domain knowledge and language ability with English learning to meet future job demands （Leroux ＆ Lafleur, 1995; Khan ＆ Khan, 2015）. In the information age, the innovative technologies of mobile devices make the dramatical changes in ways of teaching and learning （Atkinson, 2011; Bierstaker, Janvrin ＆ Lowe, 2014, Pittaway, 2012; Yang ＆ Che, 2015）. The focus of this study aims to examine ESP college students＇ English learning performance by using Context Aware Mobile Situated Learning （CAMSL） in Tourism and Hospitality Management field and other majors. The mixed research method is conducted for data collection and analysis. The quantitative data are collected by examining students＇ learning performance; the qualitative data are allowed to understand the students＇ perspective toward their role in using the CAMSL with Tourism related content. Eight-three students are randomly selected and divided into two groups： 42 students are assigned in the experimental group A （CAMSL）, and 41 students are assigned in control group. Two groups of students receive pretest and posttest to examine their English performance. Besides, twenty students from group A and B are selected for online survey. The survey is mailed directly to students＇ email account. Results represented by using CAMSL show the significant improvement on students＇ learning performance. In addition, the survey data indicate the benefits of using the CAMSL help students enhance their academic discourse, develop their learned knowledge to represent their profession, use English properly to speak themselves up, and provide the effectiveness of obtain domain knowledge in future workplace.

Mobile Assisted Chinese Learning as a Foreign Language:An Overview of Publications between 2007 and 2019

This paper presents a critical overview of studies on mobile assisted language learning(MALL)in teaching Chinese as a foreign language(CFL)during the period 2007−2019.In the review,keyword and reference searches were conducted to identify and select empirical studies during the review period.Thematic and frequency analyses were employed on the data.This identified methodological trends and research outcomes in the reviewed studies.As shown in the results,most of the reviewed studies used qualitative methods to examine the effect of mobile CFL learning on formal learning in higher education settings.These studies document the positive impact that mobile technology has on CFL learning.Their attention is primarily on the use of mobile learning in Chinese vocabulary acquisition,language skill development and mobile seamless learning.Suggestions are provided for further research to support continuous mobile assisted CFL teaching and learning.

On the Growth Mechanism of Nickel and Cobalt Nanowires and Comparison of Their Magnetic Properties

Magnetic nanowires(NWs)are ideal materials for the fabrication of various multifunctional nanostructures which can be manipulated by an external magnetic fi eld.Highly crystalline and textured nanowires of nickel(Ni NWs)and cobalt(Co NWs)with high aspect ratio(~330)and high coercivity have been synthesized by electrodeposition using nickel sulphate hexahydrate(NiSO_(4)·6H_(2)O)and cobalt sulphate heptahydrate(CoSO_(4)·7H_(2)O)respectively on nanoporous alumina membranes.They exhibit a preferential growth along〈110〉.A general mobility assisted growth mechanism for the formation of Ni and Co NWs is proposed.The role of the hydration layer on the resulting one-dimensional geometry in the case of potentiostatic electrodeposition is verified.A very high interwire interaction resulting from magnetostatic dipolar interactions between the nanowires is observed.An unusual low-temperature magnetisation switching for fi eld parallel to the wire axis is evident from the peculiar high fi eld M(T)curve.

The Effect of Saddle-Assistive Device on Improving the Gait Parameters of Patients with the Lower Limbs Weakness:A Pilot Study

To help walking,using assistive devices can be considered to reduce the loads caused by weight and to effectively decrease the propulsive forces.In this study,a mobility Saddle-Assistive Device(S-AD)supporting body weight while walking was evaluated on two healthy volunteers.This device is based on the support of body weight against gravity with the help of a saddle,which is not used in other passive mobility assistive devices.To prove the efficiency of this device,the experimental results obtained while walking with this device were compared with those related to walking without the assistive device.The results showed that this device could significantly reduce the forces and torque of the lower and upper limbs when walking.By distributing the load on the saddle,the vertical force and the propulsive force in the best conditions were decreased to 46.7%and were increased to 13.7%in body weight,respectively.Using a S-AD can help patients with lower limbs weakness and elderly people to walk.