Distance between plugs in multi-stage plug discharge tunnel

1472-1475For multi-stage plug discharge tunnel, the distance between the upper and the lower plug affects plug’s energy dissipation capacity, and it is also an important index in multi-stage plug design. In the present paper, the reasonable distance between the upper and the lower plug in multi-stage plug discharge tunnel are researched by physical model experiment. The research result shows that when the contraction ratio is in the scope of 0.4~ 0.8, the reasonable distance between the upper and the lower plug in multi-stage plug discharge tunnel is equal to or more than 5.5D

Sharp-edged orifice plate’s wall pressure characteristics

952-956The minimum wall pressure coefficient of orifice plate and its wall pressure distribution relating to tunnel’s and dissipater’s safety are important indices for this energy dissipater design. In the present paper, the minimum wall pressure coefficient of sharp-edged orifice plate was analyzed; meanwhile, the characteristics of sharp-edged orifice plate wall pressure distribution were also analyzed. The research result has shown that the minimum wall pressure coefficient was mainly dominated by the contraction ratio of the orifice plate. The less is the contraction ratio of the orifice plate, the larger is the minimum wall pressure coefficient. The effect of orifice plate’ thickness on the minimum wall pressure coefficient was not obvious and could be neglected. When Reynolds number is more than 105, it has little impact on the minimum wall pressure coefficient. Wall pressure begins to drop down dramatically before 0.5D orifice plate, reaches minimum at the end of orifice plate, and then recovers normally when flows arrival at 3D away after orifice plate. An empirical expression was presented to calculate the minimum wall pressure coefficient. Experimental data illuminate that calculation results by using empirical expression coincided with experiment results

Poly[bis­[μ-1,4-bis­(1,2,4-triazol-1-ylmeth­yl)benzene-κ2 N 4:N 4′]dichloridomanganese(II)]

The MnII atom in the title coordination polymer, [MnCl2(C12H12N6)2]n, lies on a center of inversion in a six-coordinate octa­hedral environment comprising four N-atom donors from four N-heterocyclic ligands and two chloride atoms. Bridging by the ligands results in a layer structure of a 14.79 (5) × 14.79 (5) Å (4,4) rhombic net topology, with the MnII atoms all lying on a plane. The parallel layers stack in an ABCABC… manner through inter­layer C—H⋯N and C—H⋯Cl hydrogen bonds

A subject-specific EMG-driven musculoskeletal model for applications in lower-limb rehabilitation robotics

Robotic devices have great potential in physical therapy owing to their repeatability, reliability and cost economy. However, there are great challenges to realize active control strategy, since the operator’s motion intention is uneasy to be recognized by robotics online. The purpose of this paper is to propose a subject-specific electromyography (EMG)-driven musculoskeletal model to estimate subject’s joint torque in real time, which can be used to detect his/her motion intention by forward dynamics, and then to explore its potential applications in rehabilitation robotics control. The musculoskeletal model uses muscle activation dynamics to extract muscle activation from raw EMG signals, a Hill-type muscle-tendon model to calculate muscle contraction force, and a proposed subject-specific musculoskeletal geometry model to calculate muscular moment arm. The parameters of muscle activation dynamics and muscle-tendon model are identified by off-line optimization methods in order to minimize the differences between the estimated muscular torques and the reference torques. Validation experiments were conducted on six healthy subjects to evaluate the proposed model. Experimental results demonstrated the model’s ability to predict knee joint torque with the coefficient of determination (R2) value of 0.934±0.0130.934±0.013 and the normalized root-mean-square error (RMSE) of 11.58%±1.44%11.58%±1.44%

Path Control of a Rehabilitation Robot Using Virtual Tunnel and Adaptive Impedance Controller

Interactive control strategies have been widely used in many rehabilitation robotic devices. The distinctive feature of these strategies is that the patient can be encouraged to actively participant in the therapy program. In this paper, a novel adaptive impedance control method, which allows the patient to actively influence the robot movement trajectory, is presented. The control algorithm developed in this paper is capable of regulating the desired impedance according to the patient's actual deviation from the desired path and the dynamic relationship between patients' motion intention and the reference trajectory. A virtual tunnel surrounding the reference trajectory is designed to ensure the patient's range of motion is always physiologically meaningful. The proposed rehabilitation strategy encourages participants to make contributions to rehabilitation training task as much as possible, which may facilitate provoking motor plasticity and motor recovery. Preliminary experiments with several healthy subjects were conducted to evaluate the feasibility and effectiveness of this strategy. Experimental results demonstrated that subjects could successfully finish the tracking task assisted by robot with the proposed control algorithm

Multifocal micronodular pneumocyte hyperplasia with a novel mutation in TSC1: a case report

We report on a 34-year-old woman diagnosed with tuberous sclerosis complex. The patient was admitted for respiratory manifestations, while multi-organ involvement made the diagnostic process challenging. Genetic testing revealed a novel mutation TSC1 c.2094_2110del (p.His699Ter), which expands the disease-causing variant spectrum. Our results may facilitate the disease diagnostics and help to devise genetic counseling and targeted gene therapy