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In this paper, optimal design of a 2-DOF Parallel Kinematic Mechanism (PKM) is presented. This mechanism consists of three legs. Out of these three one is passive constraint leg and remaining two are act as active actuators. Inverse kinematics is first carried out in order to find the joint variables position for given tool position. The uniformity of the tool platform motion is found by Global Conditioning Index (GCI). Stiffness model for actuator assembly of the PKM is derived. Uniform stiffness of the PKM is obtained using Global Stiffness Index (GSI). Optimal dimensions of the PKM are obtained using Genetic Algorithm (GA) and Particle Swarm Optimization (PSO). Optimal dimensions of the PKM are obtained separately using single objectives of GCI and GSI. Finally inverse dynamics is presented using Lagrangian method. The Grand Total Actuator Force (GTAF) is computed for 2-DOF while the moving platform travels along a circular trajectory.

Objectives: Parallel Kinematic Machines (PKMs) are closed loop mechanisms. The present study is to find optimal workspace volume of two configurations of translational 3-DOF PKM and optimal location for machining. Methods/ analysis: Kinematic analysis is carried out to find the joint angles of the two configurations of the PKM. Optimal dimensions of two configurations of PKM are obtained considering Workspace Volume Index (WVI) as objective. A source code is developed in MATLAB to find the optimal dimensions using Genetic Algorithms (GAs) and Particle Swarm Optimization (PSO). Velocity analysis is carried out for configuration-I. The optimal location for best machining for configuration-I is identified using condition number of the jacobian matrix of the PKM. Findings: Using kinematic analysis the joint angles of the two configurations of PKM is obtained. Performance index like Workspace Volume Index (WVI) is introduced for the two configurations of PKM. Using WVI as an objective the optimal dimensions of two configurations of PKM are found using GA and PSO. It is observed from the results configuration-II has more WVI compared with configuration-I. Velocity analysis is done for configuration-I of PKM and from this analysis the location of singularities and non-singularities of the PKM was located. It was observed from the results the optimal location for machining is at the middle plane. Application/Improvements: The novelty of the present work lies in finding the optimal WVI of two configurations of 3-DOF PKM using GA and PSO. This PKM could be used as machine tool for 2-D contouring machining and other applications. Keywords: Optimal Workspace Volume, 3-DOF GA, PKM, PSO

In this paper, we fabricate a large-area chemiresitive type MoS2/graphene films sensor is grown by spray pyrolysis technique. The prepared sensor films were characterization by XRD, SEM, TEM Raman and BET analysis. The synergistic effect between MoS2 and graphene through the CVD method produces such a hierarchical layer-by-layer assembly of the thin film structure. MoS2/graphene hybrid films not only show enhanced NO2 sensitivity compared to NO2 sensitivity alone. Graphene or MoS2 films, but they also exhibit characteristics of rapid response and strong reproducibility. Selectiveness and stability findings demonstrate the outstanding sensing properties of the MoS2 thin film sensor. The MoS2/G showed higher sensitivity (81%) towards NO2 gas at the concentration of 1000 ppm followed by graphene (22 %) and MoS2 (45 %) based sensors in sequence. The MoS2/G sensor also exhibits fast response (12 s) and recovery time (17 s) than other sensor samples. The concept of operation and sensing mechanism behind their impressive results has also been studied in depth. The effect of humidity on the performance of gas sensing was also discussed in the point of practical device applications.

Power integrated circuits (ICs) have developed solutions for charging systems and power management system for battery powered devices. The main purpose of a battery management system comprises handling the charging cycle to limit the charging time without focusing on the battery. It also monitors the present status of the battery and reports the fault conditions if any malfunction or error occurs. This system is based on a smart LiFePO4 battery for offline UPS, which is used to power up a home AC application with 230VAC/50Hz. The main reason to select the LiFePO4 battery life cycle, it is made up of non-toxic material and this battery is not overheated or catches fire in case of overcharging or overload. In this system, the Arduino UNO microcontroller is used and it takes care of the parameters like battery charging voltage, charging current, and high voltage cutoff at backup mode. It also monitors the battery voltage, battery current, low voltage cutoff, and overload protection at inverter mode.

User generated content in the social media platforms are being considered as an important source for information about consumers and other emerging trends by the businesses. Using Twitter analytics, the paper presents insights on trends and discussions about the Internet of Things (IoT). Using relevant hashtags, 40,387 tweets were collected in early 2016. The analysis had followed three major approaches: descriptive analysis, content analysis and network analysis. The tools R and NodeXL were used for the analysis. The findings showed major themes like business concerns, scope of applications, security, emerging smart technologies and manufacturing. The sentiments of emotions and polarity differed across these themes. The top individual and industrial influencers were identified. The analysis also detected the highly-associated words and hashtags, and different user communities and how they are connected. Business implications of the findings and limitations are also elaborated.

Dear Editor,After reading the editorial on evidence-based physiotherapy practice by Sundelin [1], I would like to highlight some of the other issues that restricts physiotherapists from incorporati...

User generated content in the social media platforms are being considered as an important source for information about consumers and other emerging trends by the businesses. Using Twitter analytics, the paper presents insights on trends and discussions about the Internet of Things (IoT). Using relevant hashtags, 40,387 tweets were collected in early 2016. The analysis had followed three major approaches: descriptive analysis, content analysis and network analysis. The tools R and NodeXL were used for the analysis. The findings showed major themes like business concerns, scope of applications, security, emerging smart technologies and manufacturing. The sentiments of emotions and polarity differed across these themes. The top individual and industrial influencers were identified. The analysis also detected the highly-associated words and hashtags, and different user communities and how they are connected. Business implications of the findings and limitations are also elaborated.

Objective: While the female predominance in WHO grade I meningiomas is widely appreciated, it is also recognized that males have a tendency for more biologically aggressive tumors. The mechanisms by which sex can affect meningioma grade and growth are not fully understood yet. Methods: We performed[for full text, please go to the a.m. URL], 70. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Skandinavischen Gesellschaft für Neurochirurgie

BACKGROUND: Radial club hand (RCH) is characterized by a wide array of hand and forearm anomalies. Various treatment approaches have been described depending upon the stages of RCH. The major drawback of these studies is that the effectiveness of these interventions was reported on clinical and radiological outcomes. With the increasing focus on patient-centered care nowadays, we wanted to identify the components associated with functioning and evaluate the effectiveness of two surgical procedures on functional outcomes using the International Classification of Functioning, Disability and Health (ICF)-based tools. MATERIALS AND METHODS: We identified 14 children from our records (nine boys, five girls) with a mean age of 5.6 years, classified as Bayne types III–IV and classified them into two groups; those who were operated by centralization (group 1) and ulnarization of the carpus with ulnar shortening osteotomy procedure (group 2). The outcomes were evaluated by the brief ICF core set for the child and youth with cerebral palsy up to the age of 5 and the brief ICF core set for hand conditions for a period of 1 year after surgery. RESULTS: The results showed that both the operative techniques showed improvement in the structure component (s730-structure of upper extremity). ICF categories of d445-hand and arm use, d530-toileting, and d880-engagement in play showed a change in frequencies of more than 40% after surgery and were maintained till follow-up. However, categories related to muscle power functions (b730), muscle tone (b735), fine hand use (d440), hand and arm use (d445) and engagement in play (d880) showed no significant improvement (p > 0.05). There were no differences between both the surgical procedures in improving the outcomes (p > 0.05). CONCLUSION: We conclude that surgical techniques may be more appropriate to improve the cosmetic or structural appearance of the upper extremity than functioning.

Approximate circuits are the basic hardware building blocks of approximate computing platforms. Manual approximate designs of simple arithmetic circuits (adders and multipliers) have demonstrated the potential for efficiency improvements using approximate circuits. However, their broader adoption requires systematic methodologies that can create approximate implementations for any arbitrary circuit. An approximate circuit can be viewed as realizing a logic function that slightly deviates from the original specification, while falling within a specified quality constraint. A design automation methodology should therefore enable the generation of “correct-by-construction” approximate circuits that are guaranteed to satisfy designer-specified quality constraints.