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This paper focuses on the quality characteristics of steamed and boiled blue whiting fish (Micromesistius poutassou) cracker, with the aim of encouraging and promoting the use of this small pelagic inexpensive, readily available fish in food production and reducing post-harvest losses of the fish.

The blue whiting fish cracker was developed using boiling and steaming methods. Minced blue whiting fish meat was mixed with cassava starch in the ratio of 50:50, and other ingredients were incorporated. The dough obtained was divided into two and stuffed into two different muslin cloths. One of the stuffed dough was steamed (100°C for 15 min), whereas the other was boiled in water for 90 min. The boiled and steamed doughs were cooled at 4°C for 12 h, sliced at 2 mm thickness and oven dried at 50°C for 12 h to obtain non-expanded blue whiting fish crackers. The non-expanded blue whiting fish crackers were fried in vegetable oil to obtain expanded blue whiting fish crackers. The quality characteristics of the expanded crackers were determined using standard methods, and data obtained were subjected to analysis of variance; the mean scores were compared using Turkey’s (HSD) test. The sensory evaluation was done using 25 untrained panellists, and results were analysed statistically.

The study revealed the steamed fish cracker has significantly higher nutritional composition in terms of the proximate, mineral, fatty acid and amino acid compositions. Potassium was the most predominant mineral in the crackers, and copper was the least predominant mineral. The saturated fatty acid contents were 43.2 per cent (steamed) and 48.6 per cent (boiled), whereas the unsaturated fatty acid contents were 55.5 (steamed) and 48.5 per cent (boiled). The n6/n3 ratio obtained for steamed and boiled fish cracker was 4.0. The steamed fish cracker had a higher L* value, whereas the Brown index (100 − L*) of the steamed fish cracker was lower (33.4) than that of the boiled fish cracker. The linear expansion was higher for the boiled blue whiting fish crackers (41.8 per cent). The boiled blue whiting fish cracker had higher expanded starch structure than the steamed blue whiting fish cracker. The aroma and taste were highly correlated with overall acceptability.

The paper reports the quality characteristics and overall acceptability of steamed and boiled blue whiting fish crackers.

The purpose of this paper is to expose computational methods as applied to engineering systems and evolutionary processes with randomness in external actions and inherent parameters.

In total, two approaches are distinguished that rely on solvers from deterministic algorithms. Probabilistic analysis is referred to as the approximation of the response by a Taylor series expansion about the mean input. Alternatively, stochastic simulation implies random sampling of the input and statistical evaluation of the output.

Beyond the characterization of random response, methods of reliability assessment are discussed. Concepts of design improvement are presented. Optimization for robustness diminishes the sensitivity of the system to fluctuating parameters.

Deterministic algorithms available for the primary problem are utilized for stochastic analysis by statistical Monte Carlo sampling. The computational effort for the repeated solution of the primary problem depends on the variability of the system and is usually high. Alternatively, the analytic Taylor series expansion requires extension of the primary solver to the computation of derivatives of the response with respect to the random input. The method is restricted to the computation of output mean values and variances/covariances, with the effort determined by the amount of the random input. The results of the two methods are comparable within the domain of applicability.

The present account addresses the main issues related to the presence of randomness in engineering systems and processes. They comprise the analysis of stochastic systems, reliability, design improvement, optimization and robustness against randomness of the data. The analytical Taylor approach is contrasted to the statistical Monte Carlo sampling throughout. In both cases, algorithms known from the primary, deterministic problem are the starting point of stochastic treatment. The reader benefits from the comprehensive presentation of the matter in a concise manner.

In Part 1, background information on mechanical properties and metallurgy of solder alloys and soldered joints has been presented. In this part, mechanisms of damage and degradation of components and soldered joints during soldering, during transport, and during field life are discussed. Thermal shock damage of components and excessive dissolution of metallisations are the major effects during soldering. During transport, fatigue of leads and fracture may be caused by vibration and mechanical shocks respectively. During field life, degradation is governed primarily by low cycle fatigue of the solder and incidentally also by formation of intermetallic diffusion layers between solder and base metals. This article contains an extended illustration of solder fatigue of joints on a variety of component and board types. Finally, the influence of the variety of soldered constructions in electronic circuits on solder fatigue is discussed.

The purpose of this paper is to highlight the sustainability benefits of using demolition and industrial wastes as a replacement for aggregates and cement in traditional concrete mixes.

Crushed concrete from demolition sites served as a replacement for fine and coarse aggregate in some of the mixes at various ratios. In addition, ground granulated blast furnace slag, metakaolin, silica fume, and fly ash each served as a cement replacement for cement content in the mixes tested in this research at various rates. Compression strength tests, permeability, and thermal expansion tests were performed on various mixes to compare their performance to that of traditional mixes with natural aggregate, and with no cement replacement.

The compressive strength results indicated the suitability of using such demolition wastes as replacements in producing green concrete (GC) without hindering its mechanical characteristics significantly. In addition, the results indicated an enhancement in the mechanical characteristics of GC when replacing cement with pozzolanic industrial wastes and byproducts.

The research assesses the utilization of sustainable GC using recycled waste aggregate and byproducts.

The technique of graphical modelling (Whittaker, 1990) can be used to identify the dependence relationships between variables representing characteristics of recorded road accidents. It allows large multi-dimensional tables to be analysed by looking for conditional independence relationships among the variables. The variables under study can often be divided into groups that are ordered in time or by a hypothesised causal assumption. For these situations graphical chain models (Whittaker, 1990) are used to explore causal relationships between the variables. Some examples are given for a six-dimensional and a ten-dimensional contingency table.

A method extensively used in the production of optically flat and finely finished surfaces is that of lapping the surface upon a plate using a loose abrasive mixed into a slurry form with a carrying fluid. If the surfaces finished in this way are in continuous or intermittent sliding contact, it is the author's opinion that any abrasives retained in their surfaces will affect surface wear. This paper reported on some exploratory work to indicate the degree of embedment of abrasive in certain materials lapped by hand.

High‐impact PVC is ordinary, unplasticised PVC without the degree of brittleness which used to be associated with it. The physical and chemical properties of high‐impact PVC piping are outlined in this article, followed by a short section describing installation techniques. Market potentials in the water and chemical industries in particular are discussed.

Developments in higher temperature exchangers and other applications, require high strength as well as oxidation resistance at very high temperatures. In order to meet such requirements, Dour Metal has developed the ODM a new range of oxide dispersion strengthened (ODS) iron based materials. Compositional and thermomechanical manipulations can be used to develop the structure enabling the service temperature to be increased up to about 1200°C. Typical rupture strengths are presented for temperatures ranging from 900 to 1100°C. Data on oxidation and corrosion properties of various compositions are also presented. The emphasis is given to alloy ODM 751 on which most recent work has been performed. The composition of the alloy is 16.5% Cr‐4.5% Al‐0.6% Ti‐1.5% Mo‐0.5% Y2O3‐bal Fe and provides the best compromise between strength, formability and oxidation resistance. Measurements of longitudinal creep at 1100°C to 1200°C on ODM 751 tubes show the outstanding properties of the alloy in this range of temperatures.

A simple beam element is developed for the solution of large deflection problems. The total Lagrangian formulation is based on the kinematic relations proposed by Reissner for finite rotations and stretching as well as shearing of plane beams. The motion is discretized by linear expansions of the global displacement components and the cross‐sectional rotation in two‐dimensional Euclidean space yielding a simple beam element with three degrees of freedom at the two nodes. The shear locking is reduced by selective integration in order to eliminate the spurious shear constraint similar to interdependent variable interpolation. The large rotation formulation is compared with two forms of moderate rotation theories which have been used in the past to develop the geometric stiffness properties for linear stability analysis of the so‐called Mindlin plate elements. The predictive value of different geometric stiffness approximations is assessed with several examples which range from the static and kinetic stability analysis of the classical Euler‐column to the large deflection problem of a clamped beam.