Development of an urban health and wellbeing index for work precincts: A comparative study in Sydney,Australia

Work precincts are recognized for their significant role as generators of employment and associated commerce within urban areas. This study describes a method for analyzing the physical characteristics of urban work precincts in promoting the health and wellbeing of their occupants. The following physical parameters are analyzed: public transport accessibility, green and blue spaces, food environments, fitness facilities, supermarkets, and grocery stores. The parameters are assessed using quantitative spatial analysis based on street network data, as well as point of interest data acquired from OpenStreetMap (OSM). The streets and their intersections are stored in the OSM database as links and nodes, respectively. The evaluation of the performance metrics involves measuring the street network distance from each node to the closest node of interest for each parameter. The metrics are then combined, forming an urban health and wellbeing index (UHWI), which can be used to compare the performance of different precincts. The method was tested by investigating four work precincts in Sydney, Australia, all hosting a large office building belonging to the same business institution. Our results identified two of the four precincts with a high UHWI and resulted in the identification of one underperforming precinct.     

Effects of minor Cu and Si additions on glass forming ability and mechanical properties of Co-Fe-Ta-B Bulk metallic glass

Effect of Cu and Si substitutions for Co and B on the glass forming ability (GFA) of Co_(43-x)Cu_xFe₂₀Ta_5.5B_(31.5-x)Si_y (x=0-1.5 and y=5-10) were systematically investigated by X-ray diffraction, optical microscopy, scanning electron microscopy, and differential scanning calorimetry. In order to evaluate the contribution of copper and silicon, appropriate amounts of copper and silicon were individually introduced to the base alloy composition. By using the effects of copper and silicon together, significant enhancement was obtained and the critical casting thickness (CCT) of the base alloy was increased three times from 2 mm to 6 mm. Moreover, mechanical properties of the alloys were examined by compression tests and Vickers hardness measurements. The compression test results revealed that the glassy alloys having enhanced GFA shows high strength of about 3500-4000 MPa. In addition, existence of (Co,Fe)₂B and (Co,Fe)_20.82Ta_2.18B₆ crystalline phases in glassy matrix influences the hardnesses of the alloys compared to monolitic glassy structure having hardness of about 1200 Hv.     

An ISA-95-based manufacturing intelligence system in support of lean initiatives

Increasingly, lean manufacturing is being applied by leading manufacturers throughout the world. As continuous improvement cycles of many lean initiatives focus on cost control and improving quality of product, turbulence in world markets demand more agility and responsiveness without compromising cost and quality. In order to attain more agility, information and communication technologies are utilized by many manufacturers, both at shop floor systems and enterprise resource planning (ERP) layer. This increasing trend created a disconnect that presents an opportunity for manufacturing intelligence (MI) systems. Bridging this gap, MI can enhance responsiveness by providing visibility into operations and improve quality by tracking long-term data, hence support the continuous improvement philosophy of lean manufacturing. This paper presents an ISA-95-based MI framework that can support lean manufacturing by contextualizing low-level shop floor data using production operation information from ERP systems. Processed data is presented on dashboards via Key Performance Indicators, which managers can use to determine appropriate action for their lean initiatives, timely and effectively.     

A SNP-based PCR–RFLP capillary electrophoresis analysis for the identification of the varietal origin of olive oils

Authenticity and traceability of high quality monovarietal extra virgin olive oils is a major concern for markets and consumers. Although analytical chemistry techniques are widely used to satisfy these needs recently developed DNA-based methods can serve as complementary approaches. A SNP database comprising 10 Greek olive varieties was constructed and five SNPs, residing in restriction sites, were selected for the development of a PCR–RFLP capillary electrophoresis method to discriminate these varieties using leaf DNA as template. An identification key was constructed indicating that five SNPs were adequate to discriminate nine out of the 10 varieties. As a proof of principle the assay was applied on DNA extracted from five of their corresponding monovarietal olive oils. Three SNPs were able to identify the varietal origin of these olive oils confirming the validity of this approach.     

On the Application of Dynamic Scan Chain Partitioning for Reducing Peak Shift Power

Scan-based testing of integrated circuits results in significant switching activity during the shift operations, dissipating excessive power levels. When such levels are beyond the peak power level under which the chip can functionally operate at, it may lead to an unexpected behavior of the design, resulting in a yield loss. One of the most effective solutions to reduce peak shift power is to partition the scan chains into multiple groups, wherein a single group is active at any time instance within a shift cycle. The partitioning of the chains into groups can be performed statically, i.e., per test set, or dynamically, i.e., per test pattern. In this work, we address the application of dynamic scan chain partitioning for reducing peak shift power. First, we address the application of dynamic partitioning to test delay faults in at-speed test techniques. Then, we formulate the scan chain partitioning problem via Integer Linear Programming (ILP), in order to evenly distribute the transitions produced by any pattern over multiple time instances within the shift cycle, maximally reducing the peak shift power. Finally, we evaluate the power reduction benefit of dynamic partitioning through an extensive set of experiments using different scan configurations and test set characteristics of benchmark circuits as well as industrial designs. The results indicate that dynamic partitioning provides significant reduction to peak shift power over static partitioning methods, and that the benefit is accentuated in scan architectures with fewer scan chains, test sets with more don’t care bits, and designs with larger variances of weight differences for transitions in the scan cells.     

Hydrogel assisted nickel nanoparticle synthesis and their use in hydrogen production from sodium boron hydride

In this study, hydrogels were synthesized from 2-acrylamido-2-methyl-1-propansulfonic acid (AMPS) via a photo polymerization technique. Approximately 100 nm Ni metal nanoparticles were generated in situ inside these p(AMPS) hydrogel networks and used as a catalyst in hydrogen production by hydrolysis of sodium boron hydride in a basic medium. The effects of several parameters on the hydrolysis reaction such as the amount of catalyst, the initial concentration of NaBH₄, and the temperature were investigated. The activation energy, activation enthalpy and activation of entropy for the reaction were calculated as 42.28 kJ mol⁻¹, 39.59 kJ mol⁻¹ and −171.67 J mol⁻¹ K⁻¹, respectively.     

Hydrogen production from ammonia borane via hydrogel template synthesized Cu, Ni, Co composites

In situ Co, Cu and Ni nanoparticles were synthesized by chemical reduction of the absorbed Co (II), Cu (II) and Ni (II) ions inside hydrogel networks prepared from 2-acrylamido-2-methyl-1-propansulfonic acid (AMPS) and were used as a catalyst system in the generation of hydrogen in hydrolysis of ammonia borane (AB). Several parameters affecting the hydrolysis reaction such as the type of the metal, the amount of catalyst, the initial concentration of AB, and temperature, were investigated. The activation energy values in the hydrolysis reaction of AB solution in the presence p(AMPS)-Co, p(AMPS)-Cu and p(AMPS)-Ni catalyst systems were calculated as E_a = 47.7 kJ mol⁻¹, 48.8 kJ mol⁻¹ and 52.8 kJ mol⁻¹, respectively. Thus, the catalytic activity of the metal nanoparticles prepared inside the same hydrogel matrix was found to be Ni < Cu < Co.     

Forced convection heat transfer inside an anisotropic porous channel with oblique principal axes: Effect of viscous dissipation

An analytical study on laminar and fully developed forced convection heat transfer in a parallel-plate horizontal channel filled with an anisotropic permeability porous medium is performed. The principal axis of the anisotropic porous medium is oriented from 0 to 90 degrees. A constant heat flux is applied on the outer wall of the channel. Both clear (Newtonian) fluid and Darcy viscous dissipations are considered in the energy equation. Directional permeability ratio parameter A¹ is defined to combine both the effect of the dimensionless permeability ratio parameter K¹=(K₁/K₂) and orientation angle φ into one parameter. The effects of the parameter A¹, the Darcy number Da and the modified Brinkman number Br¹ on the heat transfer and fluid flow characteristics in the channels are investigated and presented in graphs. The obtained results show that the parameters A¹, Da and Br¹ have strong effects on the dimensionless normalized velocity and temperature profiles as well as on the Nusselt number. It is found that for a particular value of A¹, called as critical value A_cr¹, the external heat applied to the surface of the channel is balanced by the internal heat generation due to viscous dissipation and the bulk mean temperature approaches the wall temperature. Hence, the Nusselt number approaches infinity for the critical values A_cr¹.     

14C analysis via intracavity optogalvanic spectroscopy

A new ultra sensitive laser-based analytical technique, intracavity optogalvanic spectroscopy (ICOGS), allowing extremely high sensitivity for detection of ¹⁴C-labeled carbon dioxide has recently been demonstrated. Capable of replacing accelerator mass spectrometers (AMS) for many applications, the technique quantifies zeptomoles of ¹⁴C in sub micromole CO₂ samples. Based on the specificity of narrow laser resonances coupled with the sensitivity provided by standing waves in an optical cavity, and detection via impedance variations, limits of detection near 10^{?15 14}C/¹²C ratios have been obtained with theoretical limits much lower. Using a 15 W ¹⁴CO₂ laser, a linear calibration with samples from 5 × 10^?15 to >1.5 × 10^?12 in ¹⁴C/¹²C ratios, as determined by AMS, was demonstrated. Calibration becomes non-linear over larger concentration ranges due to interactions between CO₂ and buffer gas, laser saturation effects and changes in equilibration time constants. The instrument is small (table top), low maintenance and can be coupled to GC or LC input. The method can also be applied to detection of other trace entities. Possible applications include microdosing studies in drug development, individualized sub-therapeutic tests of drug metabolism, carbon dating and real time monitoring of atmospheric radiocarbon.     

A Simple Top‐Down/Bottom‐Up Approach to Sectored,Ordered Arrays of Nanoscopic Elements Using Block Copolymers

A top‐down/bottom‐up approach is demonstrated by combining electron‐beam (e‐beam) lithography and a solvent annealing process. Micellar arrays of polystyrene‐block‐poly(4‐vinylpyridine) (PS‐b‐P4VP) with a high degree of lateral order can be produced on a surface where sectoring is defined by e‐beam patterning. The e‐beam is used to crosslink the block copolymer (BCP) film immediately after spin‐coating when the BCP is disordered or in a highly ordered solvent‐annealed film. Any patterns can be written into the BCP by crosslinking. Upon exposure to a preferential solvent for the minor component block followed by drying, cylindrical nanopores are generated within the nonexposed areas by a surface reconstruction process, while, in the exposed areas, the films remain unchanged. Nickel nanodot arrays can be placed over selected areas on a surface by thermal evaporation and lift‐off process.