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Ramp junctions have been successfully synthesized utilizing an Y_1-xPr_xBa₂Cu₃O_y barrier with a continually graded concentration of Pr. The properties of these junctions are dominated by the barrier material rather than the boundary. Also, the damaged ramp surface is excluded from the weak link region so its influence is minimized. The Josephson coupling occurs at the naturally formed S/N interfaces within the Y_1-xPr_xBa₂Cu₃O_y layer. Thus it leads to a highly transparent S/N boundary and greatly enhances the performance of the junctions. The effective thickness of the barrier can be varied even post fabrication, depending on the measuring temperature and the concentration gradient. The temperature dependence of the barrier thickness and Josephson properties were investigated and compared with those junctions with a conventional single barrier. These unique features should motivate further studies on the nature of these junctions.

Connected autonomous vehicles (CAV) are currently under development, and the mixed flow with CAV would make the traffic states more complicated. Due to the lack of mature applications, the future traffic with CAV are still full of uncertainties. Under the new situation, the traditional cellular automata (CA) model is in need of upgrade. To discover the characteristics of traffic flow under different CAV penetration rates, and considering the particularity of the ramp segments on freeway, this paper updates the current CA model and analyzes the car-following and lane-changing behavior of mixed traffic flow under the intelligent network. Results show that, as the CAV penetration rate continues to increase, the road operation performance continues to improve, and the capacity of the road segment increases accordingly.

This paper presents the design of linear ramp generator and digital BIST for an on-chip ADC testing. It replaces the costly and time-consuming traditional mixed signal test methods like DSP-based testing, ATE, etc. The proposed on-chip analog ramp generator uses only a few transistors to generate linear ramp signal. A TIQ comparator based 8-bit flash ADC is taken under test. The output response of the ADC is analyzed in the digital BIST to measure the primary nonidealities affecting the linearity and accuracy of the data conversion. In testing, ADC generates the digital data sequence as a test pattern in response to the ramp input while digital BIST estimates the conversion error. This method does not require DAC and any additional components which increase the area overhead of ADC test. The complete design of ramp generator is integrated with TIQ flash ADC and verified in 0.18$\mu$m CMOS technology with 1.8V of the power supply and 100kHz of the input frequency. Measurement of nonidealities shows that the design of an 8-bit flash ADC has good accuracy in data conversion with the differential nonlinearity of $-$0.24/$+$0.17LSB and integral nonlinearity of $-$0.44/$+$0.04LSB.

Locomotor state transitions are challenging for transfemoral (TF) amputees due to the lack of active knee control even in the current powered prosthetic devices. Myoelectric activation has been used successfully to classify steady-state locomotion states, but classification of transitions between locomotion states remains a challenge, especially for TF amputees. The purpose of this study was to determine if lower-extremity muscle activation differences between pre-transition and transition gait cycles occur in the involved or uninvolved limb of TF amputees during locomotion state transitions. Surface electromyography (EMG) was collected from residual muscles on the involved limb and from the uninvolved limb from five TF amputees as they transitioned between different locomotion states (level ground, ramp ascent/descent, stair ascent/descent). Statistical parametric mapping (SPM) was used to assess differences in activation. When analyzed as a group, the only significant differences were observed in the vastus lateralis of the uninvolved limb. High inter-subject variation reduced the significance of other pattern differences. Further inspection revealed that the individual subjects expressed three different recruitment patterns. These recruitment patterns may indicate compensatory strategies adopted by the subjects over the years since amputation. Furthermore, the separate recruitment patterns suggest the need for individualized locomotion transition classification algorithms rather than a general classification scheme.