Optimisation of cutting parameters for minimizing carbon emission and maximising cutting quality in turning process

Modern manufacturing systems are faced with the challenge of reducing the carbon emission related to manufacturing technologies. Machining centres consume large amounts of energy and as a consequence; carbon emissions are generated owing to this consumption. This paper presents a design of experiment work related to the optimisation of machining factors in the turning process of aluminium alloys. Carbon emission and surface quality were concurrently optimised. A set of experimental scenarios was set using a Box–Behnken design and the response surface methodology was applied to get the regression model for the carbon emission and surface roughness during turning process. The relationship between factors and the responses (carbon emission and surface quality) was investigated using surface plots. Furthermore, the desirability function method using the Response Optimizer tool in MINITAB and goal programming methodology was used to obtain the values of the parameters that achieved minimum surface roughness and a minimum quantity of carbon emission.     

The elusive effects of workplace diversity on innovation

We investigate econometrically whether cultural diversity at the workplace boosts innovation. Our longitudinal linked employer‐employee data combines two innovation surveys, with Dutch administrative, tax and regional data. We analyse the determinants of a firm's product and process innovations with respect to the firm's internal resources, employee composition and regional agglomeration externalities. We reconfirm the findings of several other recent studies showing a positive partial correlation between innovation and cultural diversity in pooled cross‐sectional data; in some cases even when accounting for reverse causation. However, no statistically significant traces of benefit for innovation from cultural diversity remain after introducing firm fixed effects.     

Investigating flow patterns in a channel with complex obstacles using the lattice Boltzmann method

In this work, mesoscopic modeling via a computational lattice Boltzmann method (LBM) is used to investigate the flow pattern phenomena and the physical properties of the flow field around one and two square obstacles inside a two-dimensional channel with a fixed blockage ratio, β=1/4, centered inside a 2D channel, for a range of Reynolds numbers (Re) from 1 to 300. The simulation results show that flow patterns can initially exhibit laminar flow at low Re and then make a transition to periodic, unsteady, and, finally, turbulent flow as the Re get higher. Streamlines and velocity profiles and a vortex shedding pattern are observed. The Strouhal numbers are calculated to characterize the shedding frequency and flow dynamics. The effect of the layouts or configurations of the obstacles are also investigated, and the possible connection between the mixing process and the appropriate design of a chemical mixing system is discussed.     

Prioritization methodology of dangerous substances for water quality monitoring with scarce data

Monitoring and control of dangerous substances discharged into receiving waters have attracted more attention lately. Since it is not possible to analyze every single substance, a prioritization methodology is needed for the selection of those to be monitored. Existing well-developed models require significant amount of data for reliable outcomes. This paper presents a methodology to prioritize the dangerous substances having adverse effects on freshwaters in Turkey, where data are scarce. Such a methodology will also serve as a solid model for other countries with limited background data. The adopted methodology enabled the elimination of chemicals to generate a candidate list composed of 608 substances among more than 5000 substances. Further screening and prioritization were conducted using different assessment methods (i.e., Total Hazard Value, Total Impact Value, Combined Monitoring-based, and Modelling-based Priority Setting) to obtain a proposed Final Candidate Specific Pollutants List of 150 dangerous substances. The proposed Candidate National Pollutant List of Turkey was established by combining 45 priority pollutants of the European Union with a list of candidate specific pollutants. According to the outcomes of this study, monitoring and controlling of 195 dangerous substances in freshwaters are recommended. Further detailed studies should be conducted in order to observe the actual levels of these dangerous substances in freshwaters followed by a review of the monitoring list accordingly. Moreover, further revisions might be required in the proposed list due to some possible versatile conditions in terms of sampling points (i.e., change in the location of industries).     

An integrated electrochromic nanoplasmonic optical switch

We demonstrate an electrochemically driven optical switch based on absorption modulation of surface plasmon polaritons (SPPs) propagating in a metallic nanoslit waveguide containing nanocrystals of electrochromic Prussian Blue dye. Optical transmission modulation of ～96% is achieved by electrochemically switching the dye between its oxidized and reduced states using voltages below 1 V. High spatial overlap and long interaction length between the SPP and the active material are achieved by preferential growth of PB nanocrystals on the nanoslit sidewalls. The resulting orthogonalization between the directions of light propagation and that of charge transport from the electrolyte to ultrathin active material inside the nanoslit waveguide offers significant promise for the realization of electrochromic devices with record switching speeds.     

Decades of progress, or the progress of decades?

In the almost 40?years since we wrote Evaluative bibliometrics enormous advances have been made in data availability and analytic technique. The journal impact factor of the 1960s has clearly not kept up with the state of the art. However, for both old and new indicators, basic validity and relevance issues remain, such as by what standard can we validate our results, and what external use can appropriately be made of them? As funding support becomes more difficult, we should not lose sight of the necessity to again demonstrate the importance of our research, and must keep in mind that it is the relevance of our results that count, not the elegance of our mathematics.     

Scientific co-operation in Europe and the citation of multinationally authored papers

Under the sponsorship of the U.S. National Science Foundation, CHI Research, Inc. developed the bibliometric indicators for the U.S. National Science Board'sScience Indicators Reports starting withScience Indicators 1972. In the work reported here, for the Commission of the European Communities, CHI has extended the Science Indicators techniques and database to a study of publication, coauthorship and citation within 28 scientific fields related to various European Community programs.Perhaps the most important finding of the research was that internationally coauthored papers — papers authored by scientists affiliated with institutions in more than one EC country — were cited two times as highly as papers authored by scientists working at a single institution within a single country. These EC-EC internationally coauthored papers were cited as highly as EC-Non EC and Non-EC papers. This indicates that the internationally linked European science is of as high impact as any other science in the world.A second key finding was that, after compensating for national scientific size, the degree of international coauthorship did not appear to be particularly dependent upon size. However, linguistic and cultural factors were found to be very strong. The patterns of coauthorship amongst the European countries are far from homogeneous, and are quite heavily affected by linguistic, historical, and cultural factors.Finally, it was found that international coauthorship is increasing steadily, both within and outside of the Community, with some evidence that international cooperation is increasing more rapidly in scientific fields that have been targeted by the Commission.This work has been sponsored by the MONITOR programme of the Commission of the European Communities.     

Biosorption of lanthanum and cerium from aqueous solutions by Platanus orientalis leaf powder

The biosorption of lanthanum and cerium by leaves powder of Platanus orientalis was separately determined at varying experimental conditions using a batch technique. The effects of initial pH, contact time, initial metal ion concentration and temperature were investigated. The Langmuir and Freundlich isotherms were applied to represent the adsorption process. Langmuir isotherm fits the experimental data quite well. The Langmuir monolayer capacity of the sorbent is 28.65mg g^− 1 and 32.05mg g^− 1 for La and Ce(III), respectively. Thermodynamic parameters such as standard enthalpy (ΔH°), entropy (ΔS°) and free energy (ΔG°) were calculated from the slope and intercept of the plots of lnK_d versus 1/T. The results indicated that sorption was endothermic and spontaneous in nature. The work reveals that powdered leaf of Platanus orientalis is a good choice as a biosorbent for the recovery of lanthanum and cerium from aqueous solution.     

Deposition and Characterization of Tungsten Carbide Thin Films by DC Magnetron Sputtering for Wear-Resistant Applications

In this study, WC (tungsten carbide) thin films were deposited on high-speed steel (AISI M2) and Si (100) substrates by direct current magnetron sputtering of a tungsten carbide target having 7% cobalt as binding material. The properties of the coatings have been modified by the change in the bias voltages from grounded to 200 V. All the coatings were deposited at 250°C constant temperature. The microstructure and the thickness of the films were determined from cross-sectional field-emission gun scanning electron microscope micrographs. The chemical composition of the film was determined by electron probe micro analyzer. The x-ray diffractometer has been used for the phase analyses. Nanoindentation and wear tests were used to determine the mechanical and tribological properties of the films, respectively. It is found that the increase in the bias voltages increased drastically the hardness and elastic modulus, decreased the friction coefficient values and increased the wear resistance of tungsten carbide thin films by a phase transformation from metallic W (tungsten) to a nonstoichiometric WC_1?x (tungsten carbide) phase.