Concept, etiology, and pathomechanics of hallux rigidus

There is a continuous anatomical, functional and pathomechanical roadmap from functional hallux limitus to hallux rigidus. Although many etiologies for hallux rigidus have been studied it is very probable that it has a primary origin with less-than-ideal movement when we are born. Upon a restricted range of motion, symptoms may arise depending on the amount of work and how compensatory mechanisms work around the first metatarsophalangeal joint. Changes occurring at the joint that allow the transition from a sliding movement mechanism (physiological) to a rolling mechanism (pathological) may trigger anatomical and functional changes resulting in pain and dysfunction. Any surgical technique that is able to restore the sliding mechanism to the first metatarsophalangeal joint will have a positive impact on pain and function in a patient with a symptomatic functional hallux limitus/rigidus. Level of Evidence V; Therapeutic Study; Expert opinion.

An Orthogonal Wheel Odometer for Positioning in a Relative Coordinate System on a Floating Ground

This paper introduces a planar positioning sensing system based on orthogonal wheels and encoders for some surfaces that may float (such as ship decks). The positioning sensing system can obtain the desired position and angle information on any such ground that floats. In view of the current method of using the IMU gyroscope for positioning, the odometer data on these floating grounds are not consistent with the real-time data in the world coordinate system. The system takes advantage of the characteristic of the orthogonal wheel, using four vertical omnidirectional wheels and encoders to position on the floating ground. We design a new structure and obtain the position and angle information of a mobile robot by solving the encoder installed on four sets of omnidirectional wheels. Each orthogonal wheel is provided with a sliding mechanism. This is a good solution to the problem of irregular motion of the system facing the floating grounds. In the experiment, it is found that under the condition that the parameters of the four omnidirectional wheels are obtained by the encoder, the influence of the angle change of the robot in the world coordinate system caused by the flotation of the ground can be ignored, and the position and pose of the robot on the fluctuating ground can be well obtained. Regardless of straight or curved motion, the error can reach the centimeter level. In the mobile floating platform experiment, the maximum error of irregular movement process is 2.43 (±0.075) cm and the RMSE is 1.51 cm.

Telecommunications package recommendation algorithm based on Deep forest

In view of the wide variety of telecom packages and the difficulty of adapting to the needs of users, this paper introduces a recommendation model for telecom packages based on deep forests. This paper first analyzes the telecom package data, and then optimizes the deep forest according to its characteristics such as discrete, continuous attribute interleaving and high coupling characteristics, including the use of decision trees to discretize continuous features and design continuous window sliding mechanism. These methods can improve the ability of deep forest combination high coupling features. Finally, the model optimization measures were verified by detail experiments. The experimental results show that the optimized deep forest can be applied to the telecom package recommendation field. Compared with other shallow models and unoptimized deep forest models, the deep forest model has increased the F1 score by 5%; after adjusting the deep forest hyper parameters, the F1 score can be increased by 2%.

The Anti sliding Mechanism of Adjacent Pile-Anchor Structure considering Traffic Load on Slope Top

In view of the fact that the anti sliding effect analysis of the current anchor cable and anti slide pile structure is not yet complete, research on the synergy mechanism of adjacent pile-anchor composite structures under traffic load is carried out. Firstly, a free vibration analysis for the slope dynamic model is carried out by using a three-dimensional finite element numerical simulation method. By improving the slope boundary conditions of time-domain analysis, the time-domain equation of the dynamic model of traffic load acting on the top of the slope is solved accurately, and the response law of the internal force of the pile anchor composite structure is also described. The mechanism by which the pile anchor composite structure resists against the slope sliding through the internal force increment is proposed: this internal force increment is estimated to be 73.4%, while that of anchor cable is 26.6%. The composite structure presents the coordinated sharing for sliding force. The internal force of the lower row of anchor cables is 89.48 kN larger than that of the upper row, and the internal force increment is four times larger, indicating that the lower anchor cable is more effective in slope reinforcement. As the deformation at the top of the slope is greater, the prestress of the upper anchor cable should be increased to avoid the “chain failure” caused by excessive deformation. As a result, the coordination law of internal force of pile anchor is revealed, and the anti sliding sharing mechanism is clarified. A design idea of the adjacent pile-anchor composite structure is proposed, which takes 0.2‐0.3 times the remaining sliding force as the design value of prestressed anchor cable. The idea fully considers the anti sliding effect of prestressed anchor cables and reduces the design size of anti slide pile section, providing a theoretical support for optimization design of combined anti slide structure and saving project investment.

Buttons on Demand Sliding Mechanism Driven by Smart Materials and Mechanical Design

In this paper, we describe a novel human interaction platform in a car, called buttons on demand, that will serve as buttons inside the interior of a car, which can be called upon and activated when required but remain concealed and inactive when not required. The mechanism to obtain such interaction is driven by a combination of smart materials and mechanical design. The elaboration of smart materials and mechanical design employed to achieve this mechanism is discussed. A demonstration of how the buttons on demand mechanism described in this paper can potentially substitute or minimize the use of bulkier physical buttons in cars and provide the user with haptic and tactile feedback with low power consumption and fast response time is also presented.

Design and Fabrication of Wheelchair into Foldable Bed

In this paper lead screw mechanism is used to convert a wheelchair into bed and vice versa. When lead screw mechanism is operated, the foot rest which is downward goes till the level of seat of wheelchair and simultaneously the back support goes down to the same level making, its stretcher and vice versa, when it is converted into wheelchair from stretcher. Below the seat, a defecation system has been provided which is detachable and is operated by sliding mechanism. It is designed and fabricated in such a way that it can be used in hospitals as well as for personal use at home. Below the seat, a defecation system has been provided which is detachable and is operated by sliding mechanism. Also, obstacle avoiding sensor i.e., ultrasonic sensor is used to know if any obstacle will come in front of wheelchair, siren bell will ring. Keywords: Fabrication, Hospital, Mobility Aid, Lead Screw, Design, Wiper Motor, Wheelchair, Battery

Effect of Heat Treatment on Microstructure and Creep Behavior of Fe-40Ni-24Cr Alloy

Iron-nickel-chromium (Fe-Ni-Cr) alloy Haynes HR120 is an iron-nickel-based superalloy, which is extensively used in gas turbines. Hence, the materials for the fabrication of steam turbine blades should present great mechanical characteristics and creep properties. In this study, Fe-40Ni-24Cr was heat-treated at temperatures from 950 to 1250 °C. High temperature creep behavior and microstructure evolution of the selected heat-treated (1050 °C, 1200 °C, 1225 °C and 1250 °C) Fe-40Ni-24Cr alloy were assessed at temperatures of 800 °C and 900 °C under 100 MPa stress. The alloy consisted of titanium and niobium rich precipitates, namely NbC, (Nb,Ti)C, TiN and Ti(C,N) distributed in the matrix grain boundaries, which enhance the creep properties of the alloy. The hardness of heat-treated Fe-40Ni-24Cr alloy decreased with increasing temperature and grain size. The creep strain of the Fe-40Ni-24Cr alloy increased with escalation in the creep time and the temperature being under constant applied stress. Fe-40Ni-24Cr alloy shows a decrease in steady-state creep rate with an increase in grain size from 62 μm to 183 μm due to the grain boundary sliding mechanism and 183 μm to 312 μm due to the occurrence of dislocation climb. This result exhibited that grain size has a significant influence on the alloys’ high temperature creep properties.

NIR-based sensing system for non-Invasive detection of Hemoglobin for point-of-care applications

Background: Hemoglobin is essential biomolecule for the transportation of oxygen therefore; its assessment is also obligatory very frequently in innumerable clinical practices. Traditional invasive techniques have concomitant shortcomings e.g. time delay, onset of infections and discomfort, which necessitates a non-invasive hemoglobin estimating solution to get rid of these constraints in health informatics. Currently various techniques are underway in allied domain and scanty products are also feasible in the market but due to low satisfaction rate, invasive solutions are still assumed as gold standard. Recently introduced technologies are effectively evolved as optical spectroscopy and digital photographic concepts on different sensing spots e.g. fingertip, palpebral conjunctiva, bulbar conjunctiva and fingernail. Productive sensors utilize more than eight wavelengths to compute hemoglobin concentration and four wavelengths to display only Hb-index (trending of hemoglobin) either in disposable adhesive or reusable clip type sensor’s configuration. Objective: This study aims an optimistic optical spectroscopic technique to measure hemoglobin concentration and conditional usability of non-invasive blood parameters’ diagnostics at point-of-care. Methods: Two distinguishable light emitting sources (810nm & 1300nm) are utilized at isosbestic points with single photodetector (800-1700nm). With this purpose, reusable finger probe assembly is facilitated in transmittance mode based on newly offered sliding mechanism to block ambient light. Results: Investigation with proposed design presents correlation coefficients between reference hemoglobin and every individual feature, multivariate linear regression model for highly correlated independent features. Moreover, principal component analytical model with multivariate linear regression offers mean bias of 0.036 & -0.316 g/dL, precision of 0.878 & 0.838 and limits of agreement from -1.685 to 1.758 g/dL & -1.790 to 1.474 g/dL for 18 & 21 principle components respectively. Conclusion: The encouraging readouts emphasize favorable precision therefore proposed sensing system is amenable to assess hemoglobin in settings with limited resources and strengthening future routes for point of care applications.