Packing theory-based framework for evaluating resilient modulus of unbound granular materials

Enhancing the quality of granular layers is fundamental to optimise the structural performance of the pavements. The objective of this study is to investigate whether previously developed packing theory-based aggregate parameters can evaluate the resilient modulus of unbound granular materials. In this study, 19 differently graded unbound granular materials from two countries (USA and Sweden) were evaluated. This study validated both porosity of primary structure (PS) and contact points per particle (coordination number) as key parameters for evaluating the resilient modulus of unbound granular materials. This study showed that decreasing the PS porosity – higher coordination number – calculated based on the proposed gradation model, yields higher resilient modulus. Good correlation was observed between the proposed packing parameters and resilient modulus of several types of aggregates. The packing theory-based framework successfully recognised granular materials that exhibited poor performance in terms of resilient modulus.     

Heat and Mass Transfer Coefficients in Computer Simulation of Paper Drying

The development of a mathematical model and a computer program to facilitate the study of thc multi-cylinder paper drying process is presented. Experimentally determined values for different heat and mass transfer coefficients are used to ensure the physical validity of the model. A unique feature of the model is its inclusion of a mass transfer coefficient for the dryer fabric. Thus far. the mass transfer mechanisms in the web have not been included. Two heat transfer coefficients are used to tune the model to actual mill data. They areassigned values that are consistent with experimental data. The agreement between predicted and experimental data, obtained hom nine industrial paper dryers, is generally very good. The investigated basis weights range from 48 to 240 g/m2.

Calculations indicate that the condensate and contact heat transfer coefficients have a major influence on the drying process. The thermal conductivity of the paper and cylinder shell, respectively, are relatively important. whereas the influence of the fabric mass transfer coefficient and the cylinder-fabric-paper heat transfer coefficient are less pronounced. Some guidelines on how to obtain corect values are discussed.     

Numerical and experimental evaluation of the influence of the filler–bitumen interface in mastics

The successful use of additives in modified asphalt mixtures, such as warm mix asphalt, depends largely on the effect such modification has on the mastic. Previous research indicated that such modifiers do not simply change the bitumen properties, but can also change the interaction between the filler and the bitumen matrix. Understanding the effect of the properties of the fillers, the bitumen and their interaction is thus important for future asphalt mix design. In order to investigate this and to define the dominant relationships, this paper combines a numerical and experimental approach. In the experiments, the viscosities of modified and unmodified mastics with different filler concentrations and types were systematically investigated utilizing a novel testing protocol. In the numerical analyses, the Finite Element Method was utilized for a micro-mechanical analysis, in which the shape and size of the filler particles were varied in the bitumen matrix. Combining the experimental and numerical results allowed for a detailed investigation of the effect of the interface properties, with and without modifiers. The research further indicated that the effect of the shape and size of the fillers varied, depending on the interface properties. From the research relationships were established between the overall mastic viscosity and the influence of the filler–bitumen interface, considering shape and size. The conclusion of this paper can thus be useful for the effective development of modified asphalt mixtures and gives strong indications towards future research directions.     

Sorption of mercuric ion by synthetic nanocrystalline mackinawite (FeS)

Iron sulfides are known to be efficient scavengers of heavy metals. In this study, Hg(II) sorption was investigated using synthetic nanocrystalline mackinawite (a disordered phase) as a function of initial Hg(II) concentration [Hg(II)]0, initial FeS concentration [FeS]0, total chloride concentration CIT, and pH. Hg(II) sorption mechanisms are dependent on relative concentrations of [Hg(II)]0 and [FeS]0 (the molar ratio of [Hg(II)0/[FeS]0). When the molar ratio of [Hg(II)]0/[FeS]o is as low as 0.05, adsorption is mainly responsible for Hg(II) removal, with its contribution to the overall sorption increasing at lower Cl(T). As the molar ratio increases, the adsorption capacity becomes saturated, resulting in precipitation of a sparingly soluble HgS(s). XRD analysis indicates formation of metacinnabar (beta-HgS). Concurrently with HgS(s) precipitation, the released Fe(II) from FeS(s) is resorbed by adsorption at acidic pH and either adsorption or precipitation as Fe (hydr)-oxides at neutral to basic pH. Subsequently, the Fe precipitate formed at neutral to basic pH serves as an adsorbent for Hg(II). Under the conditions where either adsorption or HgS(s) precipitation is dominant, more than 99% of [Hg(II)]0 is immobilized. When the molar ratio of [Hg(II)]0/[FeS]0 exceeds 1, the sulfide concentration is no longer sufficient for HgS(s) precipitation, and formation of chloride salts (Hg2Cl2 at acidic pH and HgCl2 x 3HgO at basic pH) occurs.     

The effects of carbon monoxide on Atlantic salmon (Salmo salar L.)

Atlantic salmon were exposed to carbon monoxide (CO) before the fish were percussively killed and gill cut. The fish were compared against a control group treated identically, without CO. Salmon exposed to CO expressed no adverse reactions and were easily stunned by percussion. CO-treated salmon had an earlier onset of rigor mortis and a faster decrease in muscle pH than the control group. No significant difference in drip loss was found between salmon treated with CO and the control. A significantly deeper red colour of both gills and fillets of CO-treated salmon was observed 10 days post mortem. Significantly higher levels of plasma lactate and potassium were found in CO-treated salmon compared to control, as well as a lower level of pCO₂. Exposure to CO did not increase plasma cortisol, sodium, haematocrit or glucose; however, lactate was high. Exposure of salmon or other fish to CO could improve quality and welfare when slaughtered.     

Inferring comprehensible business/ICT alignment rules

We inferred business rules for business/ICT alignment by applying a novel rule induction algorithm on a data set containing rich alignment information polled from 641 organisations in 7 European countries. The alignment rule set was created using AntMiner+, a rule induction technique with a reputation of inducing accurate, comprehensible, and intuitive predictive models from data. Our data set consisted of 18 alignment practices distilled from an analysis of relevant publications and validated by a Delphi panel of experts. The goal of our study was to describe practical guidelines for managers in obtaining better alignment of ICT investments with business requirements. Our obtained rule set showed the multi-disciplinary nature of B/ICT alignment. We discuss implication of the alignment rules for practitioners.     

Large Strain Deformation in Uranium 6 Wt Pct Niobium

The large strain deformation of polycrystalline uranium 6 wt pct niobium (U6Nb) was studied in situ during uniaxial tensile and compressive loading by time-of-flight neutron diffraction. Diffraction patterns were recorded at incremental strains to a maximum of approximately 0.13 tensile and 0.15 compressive true strain. A discrete reorientation of the crystallographic texture under tensile straining between 0.04 and 0.08 true strain is consistent with a previously unobserved mechanical deformation twinning mechanism, identified as either a (100) or (010) mechanical twin system. Beyond this, a continuous texture reorientation towards an (010) crystal orientations indicates that a slip mechanism is likely predominant. An analogous mechanical twin system was not observed in compression at large strain.     

eTransport: Investment planning in energy supply systems with multiple energy carriers

The need for local energy planning is not reduced after liberalization. Both integrated energy companies and local governments have to consider alternative solutions across traditional supply and demand sectors and make plans for the total integrated energy infrastructure. This situation has created a need for new improved methodologies and tools for system planning and operation that include multiple energy carriers and sufficient topological details. In this paper, a novel optimisation model ‘eTransport’ is presented that takes into account both the topology of multiple energy infrastructures and the technical and economic properties of different investment alternatives. The model minimises total energy system cost (investments, operation and emissions) of meeting predefined energy demands of electricity, gas, space heating and tap water heating within a geographical area over a given planning horizon, including alternative supply infrastructures for multiple energy carriers. The model employs a nested optimisation, calculating both the optimal diurnal operation of the energy system and the optimal expansion plan typically 20–30 years into the future. The model is tested on a number of real case studies, and a full graphical user interface has been implemented. A sample case study is included to demonstrate the use of the model.     

Multi-way versus one-way constraints in user interfaces: Experience with the deltablue algorithm

The efficient satisfaction of constraints is essential to the performance of constraint-based user interfaces. In the past, most constraint-based user interfaces have used one-way rather than multi-way constraints because of a widespread belief that one-way constraints were more efficient. In this paper we argue that many user interface construction problems are handled more naturally and elegantly by multi-way constraints than by one-way constraints. We present pseudocode for an incremental multi-way constraint satisfaction algorithm, DeltaBlue, and describe experience in using the algorithm in two user interface toolkits. Finally, we provide performance figures demonstrating that multi-way constraint solvers can be entirely competitive in performance with one-way constraint solvers.