Optimum harvesting area of convex and concave polygon field for path planning of robot combine harvester

Intelligent Service Robotics - This paper presents an optimum harvesting area of a convex and concave polygon for the path planning of a robot combine harvester. A convenient optimum harvesting...     

Assessing the role of turbulence-radiation interactions in hydrogen-enriched oxy-methane flames

Statistical analysis of scalar data obtained from single-shot laser measurements in four turbulent oxy-fuel flames were carried out to develop a functional relationship for the temperature self-correlation (TSC) term for use in Turbulence Radiation Interaction (TRI) models. The developed relationship was found to be invariant with the hydrogen enrichment in the fuel, fuel jet Reynolds numbers and correlated reasonably well with the root-mean-square of temperature (T_rms). The TSC and the absorption-coefficient temperature correlation (ATC) were both modeled in terms of T_rms and employed as add-on functions in time-averaged flame simulations. Including the effects of TRI enhanced the radiant fraction by 40% and reduced outlet CO concentrations by 30% across all flames. Further, there was significant flame absorption due to the high concentrations of radiatively participating gases that would deem optically thin radiation approximations in these flames to be erroneous.     

LC-MS/MS-based determination of chloramphenicol,thiamphenicol, florfenicol and florfenicol amine in poultry meat from the Punjab-Pakistan

A simple, reliable and sensitive liquid chromatography-tandem mass spectrometry-based confirmatory method was redeveloped and validated for the simultaneous determination of chloramphenicol, thiamphenicol, florfenicol and florfenicol amine in chicken muscles. The analytes were extracted from minced chicken muscle with acetonitrile and ammoniated water mixture. A second extraction with ethyl acetate was followed by evaporation and dissolution of the residue in ammoniated methanol before defatting with n-hexane. Finally, the extract was further cleaned up by dispersive solid phase extraction using C-18 end-capped dispersive material. The validation protocol was adapted from the European Commission Decision 2002/657/EC and all the performance characteristics were successfully satisfied. The recoveries of all the analytes were found to be in the range of 86.4–108.1% and the precision values, within day and between days, ranged from 2.7% to 11% and 4.4% to 16.3%, respectively. The method was tested in various incurred samples and applied to analyse a wide range of random poultry market samples (n = 120) collected from three cities of the Punjab, Pakistan. Chloramphenicol and florfenicol residues were detected at low levels in less than 11% of the samples. Chloramphenicol was detected only in 4 samples with the concentration range of 0.17–0.477 µg kg^–1, whereas the levels of florfenicol/florfenicol amine residues detected in 9 samples ranged from 8.7 to 32.8 µg kg^–1. Moreover, most of the florfenicol residues were identified as tissue bound, extractable only after strong acid hydrolysis.     

Microhole drilling through electrochemical processes: A review

Day-to-day interest is growing in the drilling of high aspect-ratio deep microholes in various hard-to-machine and newer materials. Besides cost-effectiveness in the manufacturing process, an accurate dimension with the good surface finish is essential for microhole drilling. The conventional methods encounter various problems such as residue stresses, heat generation near cutting zone, high tool-wear, etc. Electrochemical microdrilling (ECMD) is one of the cost-effective techniques, provide a better alternative in drilling microholes with reasonably accurate dimensions and good surface finish in various industrial applications especially in computer, electronic, and aerospace industries. This article reviews current researches and developments of electrochemical processes for circular microholes drilling. It highlights the effects of various key factors (such as the development of microtools, electrolyte, inter-electrode-gap monitoring and control, etc.) on the aspect-ratio and accuracy of circular microholes, produced by ECMD. For further research, it will open up various challenging opportunities, especially in the field of (i) development and handling of microtool electrodes, (ii) development and handling of electrolytes medium, (iii) development in monitoring and controlling techniques of inter-electrode-gap, and (iv) development in strategies for process control for drilling high quality, deep and high aspect-ratio circular microholes into hard-to-machine materials using ECMD.     

Calibrating multibody ulno-humeral joint cartilage using a validated finite element model

Correct prediction of contact characteristic in multibody models is a challenging issue, which requires both employing an appropriate contact model and choosing its corresponding contact parameters. This study employed two subject specific multibody models of the ulno-humeral joint where the humerus cartilage was discretized and interacted with the ulna cartilage through a deformable contact. Parameters for the deformable contact were optimized by matching the maximum predicted contact pressure in the multibody models with contact pressures predicted in identical finite element models under axial 110 N compressive load. The performance of the optimized contact parameters and employed approach was evaluated under two other loading conditions of 80 and 140 N. Moreover, the effect of discretized element size on the contact prediction was also addressed. After optimization of the contact parameters, the difference between the multibody and FE models in terms of peak and average contact pressure, and contact area was significantly reduced (more than a factor of 10). Smaller discretization size of the humerus cartilage in the multibody models resulted in better predictions especially on highly curved regions. However, the optimized parameters of our study were different between the two elbows. This indicates that optimized contact parameters can be different not only among different joints, but also among different specimens and optimization conditions. Therefore, in order to improve contact predictions, separate contact optimization should be performed for each subject.     

Technical Analysis of Security Management in Terms of Crowd Energy and Smart Living

In this paper, a technical and statistical analysis of security system and security management is provided for crowd energy and smart living. At the same time, a clear understanding is made for crowd energy concept and next generation smart living. Various case examples have been studied and a brief summary has been provided. Furthermore, a statistical analysis has been provided in terms of security management in smart living where it is found that young technocrats give the highest importance to security management in smart living. Last but not the least, current limitation, constraints, and future scope of security implementation have been discussed in terms of crowd energy clustered with next generation smart living.     

Anion incorporation and its effect on the dielectric constant and growth rate of zirconium oxides

Mechanically polished zirconium electrodes were potentiodynamically polarized in phosphate buffer solutions of various pH values and in 0.5 lvl NaOH. The results show that the shape of the I-E curves is independent of the solution pH. At relatively low scan rates, oxygen gas evolution was observed. The oxide film thickness was calculated from the values of the charge consumed in the anodic process assuming 100% current efficiency for oxide formation below oxygen evolution (lower values for the current efficiency are assumed for potentials above oxygen evolution). Capacitance measurements, together with the calculated oxide thickness, were used to estimate values for the dielectric constant of the oxide. Two different values of the dielectric constant were obtained for the oxides formed in the range of potential below and above oxygen evolution. Also, higher dielectric constant values were obtained with increasing solution pH. Anion incorporation was assumed to increase the conductivity of the oxide films and, hence, decrease the dielectric constant. A two-layer structure is proposed for the anodically formed oxide on zirconium in aqueous solutions; an anion-free layer near the metal and an outer layer containing the incorporated anions.     

Microwave Processing of Actively Seeded Precursor for Fabrication of Polymer Derived Ceramics

An innovative, faster and nonconventional processing technique is demonstrated for preparing silicon carbide‐based ceramics derived from polymer precursor. The technique is based on microwave‐induced pyrolysis of an actively seeded, high‐purity preceramic polymer that leads to rapid fabrication of silicon carbide components. It is successfully demonstrated that it is feasible to carry out microwave‐induced pyrolysis by seeding the polymer precursor with very low volume fractions of micrometer and nanometer‐sized metal and dielectric fillers. This process allows for rapid, net‐shape, and potentially low‐cost fabrication of silicon carbide‐based materials. Mechanical properties and microstructure of the silicon carbide‐based composites fabricated using this process are characterized.     

Hierarchical Si/ZnO trunk-branch nanostructure for photocurrent enhancement

Hierarchical Si/ZnO trunk-branch nanostructures (NSs) have been synthesized by hot wire assisted chemical vapor deposition method for trunk Si nanowires (NWs) on indium tin oxide (ITO) substrate and followed by the vapor transport condensation (VTC) method for zinc oxide (ZnO) nanorods (NRs) which was laterally grown from each Si nanowires (NWs). A spin coating method has been used for zinc oxide (ZnO) seeding. This method is better compared with other group where they used sputtering method for the same process. The sputtering method only results in the growth of ZnO NRs on top of the Si trunk. Our method shows improvement by having the growth evenly distributed on the lateral sides and caps of the Si trunks, resulting in pine-leave-like NSs. Field emission scanning electron microscope image shows the hierarchical nanostructures resembling the shape of the leaves of pine trees. Single crystalline structure for the ZnO branch grown laterally from the crystalline Si trunk has been identified by using a lattice-resolved transmission electron microscope. A preliminary photoelectrochemical (PEC) cell testing has been setup to characterize the photocurrent of sole array of ZnO NR growth by both hydrothermal-grown (HTG) method and VTC method on ITO substrates. VTC-grown ZnO NRs showed greater photocurrent effect due to its better structural properties. The measured photocurrent was also compared with the array of hierarchical Si/ZnO trunk-branch NSs. The cell with the array of Si/ZnO trunk-branch NSs revealed four-fold magnitude enhancement in photocurrent density compared with the sole array of ZnO NRs obtain from VTC processes.