Recommendation engine based on derived wisdom for more similar item neighbors

Information Systems and e-Business Management - Collaborative filtering (CF) is a popular and widely accepted recommendation technique. CF is an automated form of word-of-mouth communication...     

Compact modeling of amorphous‐silicon thin‐film transistors with BSIM3

Abstract— A novel approach of modeling a‐Si:H TFTs with the industry‐standard BSIM3 compact model is presented. The described approach defines the a‐Si:H TFT drain current and terminal charges as explicit functions of terminal voltages using a minimum set of BSIM3 parameters. The set of BSIM3 parameters is chosen based on the electrical and physical characteristics of the a‐Si:H TFT and their values extracted from measured data. By using the selected BSIM3 model parameters, the a‐Si:H TFT is simulated inside SPICE to fit the simulated I‐V and C‐V curves with the measured results. Finally, the extracted BSIM3 model is validated by simulating the kickback voltage effect in an AMLCD pixel array.     

Shape Morphing-Based Control of Robotic Visual Servoing

We present an approach for controlling robotic interactions with objects, using synthetic images generated by morphing shapes. In particular, we attempt the problem of positioning an eye-in-hand robotic system with respect to objects in the workspace for grasping and manipulation. In our formulation, the grasp position (and consequently the approach trajectory of the manipulator), varies with each object. The proposed solution to the problem consists of two parts. First, based on a model-based object recognition framework, images of the objects taken at the desired grasp pose are stored in a database. The recognition and identification of the grasp position for an unknown input object (selected from the family of recognizable objects) occurs by morphing its contour to the templates in the database and using the virtual energy spent during the morph as a dissimilarity measure. In the second step, the images synthesized during the morph are used to guide the eye-in-hand system and execute the grasp. The proposed method requires minimal calibration of the system. Furthermore, it conjoins techniques from shape recognition, computer graphics, and vision-based robot control in a unified engineering amework. Potential applications range from recognition and positioning with respect to partially-occluded or deformable objects to planning robotic grasping based on human demonstration.     

Laser micro-welding of aluminum and copper with and without tin foil alloy

In this paper continuous laser welding of two dissimilar materials, aluminum and copper, was investigated. The aluminum and the copper utilized were Al3003-H14 and Cu110-H00, respectively. Two different sets of samples were laser welded; one in which a filler material, tin foil alloy (S-bond 220), was sandwiched between the aluminum and the copper and another set in which the aluminum and copper were directly welded without any filler. The foil alloy was utilized to enhance the compatibility of the two metals; aluminum and copper, reducing the brittleness of the intermetallic compound that may form and, subsequently, enhance the mechanical properties. The welding was carried out using an IPG 500 SM fiber laser. The length of the laser joint produced was 20 mm and the width was about 200 μm. The strength of the joint was evaluated by conducting the lap shear stress test. Samples in which filler foil was used exhibited a better performance in the lap shear stress test (an average of 780 N) than the samples without tin foil (an average of 650 N). The improvement in the lap shear test could be attributed to the positive effects of the filler on enhancing the compatibility of the intermetallic compound formed via diffusion. The fracture surface of both types of joints (with and without filler) was characterized using scanning electron microscope equipped with energy-dispersive X-ray (EDAX). To understand the failure initiation and propagation of the samples under tension, a finite element (FE) model was developed for the samples created with no filler material. The failure mechanism predicted from the FE model matches reasonably well with the experimental observations from EDAX analysis.     

A three-axis SOI accelerometer sensing with both in-plane and vertical comb electrodes

A three-axis capacitive accelerometer based on silicon-on-insulator is designed and fabricated. In the accelerometer, totally eight groups of capacitors are compactly arranged around an octagonal proof mass. The four groups of capacitors along orthogonal direction with in-plane comb electrodes detect XY acceleration, while the other four groups of capacitors along diagonal direction with vertical comb electrodes detect Z acceleration. Measurements of in-plane and vertical motion by the respective in-plane and vertical comb electrodes enable direct detection for all the three axes with differential capacitive sensing scheme. For the fabricated accelerometer in the size of 4 × 4 mm², the capacitance sensitivities of in-plane and out-of-plane accelerometers are 145.3 and 9.1 fF/g, respectively.     

A Petri Net based approach to determine the disassembly strategy of a product

In order to protect the environment and regain value added to products, a process known as disassembly has come into the limelight. This process is to be applied to reuse abandoned goods and materials. Manufacturers are being forced to establish disassembly plants and to develop their products' designs so as to maintain the government's dictate to dispose off their products in an environmentally responsible manner. This research presents a cost-based heuristic analysis for a circuit board assembly. Various components of the product and their assembly relationships are represented by a Petri Net diagram. Firing the transitions of the disassembly Petri Net is integrated with cost-based indices to develop an effective disassembly strategy. The methodology discussed here simplifies the decisionmaking process involved in disassembly planning. A comprehensive disassembly process planning system is proposed here and is exemplified by a case study of circuit board assembly.     

Enhancement of bending strain tolerance and current carrying property of MgB2 based multifilamentary wires

The effect of bending strain on current carrying capacity of MgB₂ multifilamentary wires was studied with 4, 8 and 16 multifilamentary wires. The critical current density (J_C) of straight wires and bent wires with 5, 10, and 15 cm diameter was measured. Both annealed & bent and bent & annealed wires were used for measurement. The J_C of annealed & bent wires were found to decrease with decrease in bent diameter and the rate of degradation of J_C decreased with increasing number of filaments, while bent & annealed wires almost retained its J_C at all diameters studied.     

Cytochrome P450 inhibitory potential of selected Indian spices — possible food drug interaction

Spices constitute an important group of food which is virtually indispensable in the culinary art. In a view, these spices feared to pose a probability to affect the disposition of conventional pharmaceuticals through inhibition of human cytochrome P450 (CYPs) enzymes. In the present study an approach has been made to evaluate the possible CYP inhibition potential with some Indian spices (Capsicum annuum, Murraya koenigii, Zingiber officinale) and their major bioactive compounds, in combination with pooled microsome; as well as commercially available recombinant human CYP3A4, CYP2D6, CYP2C9 and CYP1A2. Quantification of the bioactive compound was determined through RP-HPLC, in order to standardize the plant material. CYP–carbon monoxide (CYP–CO) complex assay result indicated that all the plants and their bioactive compounds have an interaction potential with CYPs. Fluoregenic assay results indicated that the spice extracts have higher inhibition potential comparing to their single bioactive molecule. The higher enzyme inhibition potential by the extracts may be related to the synergistic effects due to the presence of other constituents in the extract. Capsaicin and C. annuum showed the lowest IC₅₀ value and 6-gingerol and Z. officinale extract showed the highest IC₅₀ value among the entire sample tested. The entire sample showed significantly less (P < 0.001, P < 0.01) interaction potential than known inhibitors. These findings indicate that selected spices are unlikely to cause clinically relevant drug interactions involving the inhibition of major CYP isozymes.     

On the approximate frequentist validity of the posterior quantiles of a parametric function: results based on empirical and related likelihoods

With reference to a wide class of empirical and related likelihoods, we study priors which ensure approximate frequentist validity of the posterior quantiles of a general parametric function. It is seen that no data-free prior entails such frequentist validity but, at least for the usual empirical likelihood, a data-dependent prior serves the purpose. Accounting for the nonlinearity of the parametric function of interest requires special attention in the derivation. A simulation study is seen to provide support, in finite samples, to our asymptotic results.