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Modeling of material behavior by physically or microstructure-based models helps in understanding the relationships between its properties and microstructure. However, the majority of the numerical investigations on the prediction of the deformation behavior of AA2024 alloy are limited to the use of phenomenological or empirical constitutive models, which fail to take into account the actual microscopic-level mechanisms (i.e. crystallographic slip) causing plastic deformation. In order to achieve accurate predictions, the microstructure-based constitutive models involving the underlying physical deformation mechanisms are more reliable. Therefore, the aim of this work is to predict the mechanical response of AA2024-T3 alloy subjected to uniaxial tension at different strain rates, using a dislocation density-based crystal plasticity model in conjunction with computational homogenization.

A dislocation density-based crystal plasticity (CP) model along with computational homogenization is presented here for predicting the mechanical behavior of aluminium alloy AA2024-T3 under uniaxial tension at different strain rates. A representative volume element (RVE) containing 400 grains subjected to periodic boundary conditions has been used for simulations. The effect of mesh discretization on the mechanical response is investigated by considering different meshing resolutions for the RVE. Material parameters of the CP model have been calibrated by fitting the experimental data. Along with the CP model, Johnson–Cook (JC) model is also used for examining the stress-strain behavior of the alloy at various strain rates. Validation of the predictions of CP and JC models is done with the experimental results where the CP model has more accurately captured the deformation behavior of the aluminium alloy.

The CP model is able to predict the mechanical response of AA2024-T3 alloy over a wide range of strain rates with a single set of material parameters. Furthermore, it is observed that the inhomogeneity in stress-strain fields at the grain level is linked to both the orientation of the grains as well as their interactions with one another. The flow and hardening rule parameters influencing the stress-strain curve and capturing the strain rate dependency are also identified.

Computational homogenization-based CP modeling and simulation of deformation behavior of polycrystalline alloy AA2024-T3 alloy at various strain rates is not available in the literature. Therefore, the present computational homogenization-based CP model can be used for predicting the deformation behavior of AA2024-T3 alloy more accurately at both micro and macro scales, under different strain rates.

In a recent issue of the Municipal Journal there appeared a short but apparently inspired article on the subject of London Government, in which is foreshadowed another drastic and apparently imminent alteration of the system of local administration at present in operation in the Metropolis.

This study examines forecast accuracy associated with the forecast of 55 revenue data series of 18 local governments. The last 18 months (6 quarters; or 2 years) of the data are held-out for accuracy evaluation. Results show that forecast software, damped trend methods, and simple exponential smoothing methods perform best with monthly and quarterly data; and use of monthly or quarterly data is marginally better than annualized data. For monthly data, there is no advantage to converting dollar values to real dollars before forecasting and reconverting using a forecasted index. With annual data, naïve methods can outperform exponential smoothing methods for some types of data; and real dollar conversion generally outperforms nominal dollars. The study suggests benchmark forecast errors and recommends a process for selecting a forecast method.

The 24‐modulc EMIAC II analogue computer installation supplied to Sir W. G. Armstrong Whitworth Aircraft Ltd. in 1959 is to be supplemented by a further 24 modules—making 48 modules in all.

Retail buyers' decisions result in billions of dollars of merchandise being purchased and offered for sale by retailers around the world. At present, retail buyers do not appear to be adequately harnessing consumer input to improve their forecasts. The purpose of this paper is to address this issue by introducing a new approach involving both retail buyers' consensus forecasts and those from a sample of “ordinary” consumers.

The authors introduce a new approach to online forecasting that involves both retail buyers' consensus forecasts and those from a sample of “ordinary” consumers.

The results suggest an opportunity to create what are termed retail prediction markets that offer significant potential to improve the accuracy of buyers' forecasts.

The authors go beyond crowd sourcing technology and show how retail prediction markets may offer significant potential to improve the accuracy of retail buyers' forecasts.

A report on this subject has recently been issued by the Local Government Board. It owes its origin to the interest—unfortunately brief—that was aroused some two years ago, when certain allegations were made concerning the methods in vogue on the other side of the Atlantic for, the preparation of meat products intended to be placed on the English market, and has been drawn up by Dr. A. W. J. MACFADDEN. The report is based on the results obtained by Public Analysts throughout the country, who, in the performance of their official duties, were called upon to examine various samples of canned meat sent out by the United States packing houses; on certain statements made by trade representatives to Dr. MACFADDEN; and, finally, on the results of some analyses of canned meats made by Mr. ELLIS RICHARDS, F.I.C., at the request of the Board. The figures must be regarded as representative of the state of affairs then and now. By far the greater quantity of canned meat that reaches this country and is consumed therein is imported from the United States, and hence, almost of necessity, any criticisms that are made regarding this part of our food supply resolve themselves into criticisms of the Federal Meat Inspection law of the United States and the way in which it is applied by the officials there. The conclusion that Dr. MACFADDEN draws as to the efficacy of this law so far as it regards ourselves is one that was expressed in this journal in May last. He observes that “our position, so far as safeguards provided by American law are concerned, is apparently much as it was before the enactments came into force,” that “so far as the use of preservatives is concerned, the new law has not affected the conditions under which the canned meat trade has been conducted with this country in past years,” and that “the onus of protecting their inhabitants in this respect continues to rest, in the first place, with the Governments of the foreign countries themselves.” The first two statements are sufficiently damning, and the corollary is, of course, obvious. The difficulties must be tackled from this side, but the entire absence, up to the present, of all official standards renders the task of the Public Analyst and the other municipal officials who are jointly concerned with him as regards the health of the districts with which they are connected, a most difficult one, and the business of the unscrupulous “poisoner for dividends,” to use an American phrase, correspondingly easy. We go a little farther than Dr. MACFADDEN, and say that the new law does not protect us even with regard to the general wholesomeness of these products. As late as January last the Inspecting Officer of the Manchester Port Sanitary Authority had occasion to draw attention to the unsatisfactory nature of certain canned goods that were imported direct from America. The examination of a consignment of 1,200 six‐pound tins of canned meat showed that 157 tins were blown, and that 156 tins were of doubtful quality. It follows that in this single instance 1,800 pounds of garbage were exported to this country from the United States, the new law notwithstanding.

The paper aims to analyze the behavior of the Galfenol rods under bending conditions that are employed in a vibration energy harvester by illustrating the spatial variations in stress and magnetic field.

This paper describes a 3‐D static finite element model of magnetostrictive materials, considering magnetic and elastic boundary value problems that are bidirectionally coupled through stress and field dependent variables. The finite element method is applied to a small vibration‐driven generator of magnetostrictive type employing Iron‐Gallium alloy (Galfenol).

The 3‐D static finite element modeling presented here highlights the spatial variations in magnetic field and relative permeability due to the corresponding stress distribution in the Galfenol rods subjected to transverse load. The numerical calculations show that about 1.1 T change in magnetic flux density is achieved which demonstrates the effectiveness of the inspected vibration‐driven generator in voltage generation and energy harvesting. The model predictions agree with the experimental results and are coherent with the magnetostriction phenomenon.

This paper fulfils the behavior analysis of Galfenol rods under transverse load that includes both compression and tension. The compressive and tensile stresses contributions to change in magnetic flux densities in the Galfenol rods were calculated by which the effectiveness of the inspected vibration‐driven generator in voltage generation and energy harvesting is demonstrated.

In this paper, the authors aim to examine and comparatively evaluate a recently-developed metaheuristic called crystal structure algorithm (CryStAl) – which is inspired by the symmetries in the internal structure of crystalline solids – in solving engineering mechanics and design problems.

A total number of 20 benchmark mathematical functions are employed as test functions to evaluate the overall performance of the proposed method in handling various functions. Moreover, different classical and modern metaheuristic algorithms are selected from the optimization literature for a comparative evaluation of the performance of the proposed approach. Furthermore, five well-known mechanical design examples are utilized to examine the capability of the proposed method in dealing with challenging optimization problems.

The results of this study indicated that, in most cases, CryStAl produced more accurate outputs when compared to the other metaheuristics examined as competitors.

This paper can provide motivation and justification for the application of CryStAl to solve more complex problems in engineering design and mechanics, as well as in other branches of engineering.

CryStAl is one of the newest metaheuristic algorithms, the mathematical details of which were recently introduced and published. This is the first time that this algorithm is applied to solving engineering mechanics and design problems.

THE fifth of these annual conferences was held on 8 and 9 January at Southampton University. As usual the conference opened with a luncheon, at which the then Minister of Supply, the Rt. Hon. Reginald Maudling, was a speaker. The Minister pointed out that the aircraft industry was the object both of immoderate praise and intemperate criticism; in order to make a fair assessment of the industry's achievements it was necessary to compare them with those of other countries, which in practice meant the U.S.A. since no other country about which information was available had an industry of comparable size. Continental countries, although they had made outstanding technical advances, were able to export only a small fraction of the aircraft and equipment which the British industry has sent abroad in recent years.

Artificially intelligent (AI) assistant-enabled smart speaker not only can provide assistance by navigating the massive amount of product and brand information on the internet but also can facilitate two-way conversations with individuals, thus resembling a human interaction. Although smart speakers have substantial implications for practitioners, the knowledge of the underlying psychological factors that drive continuance usage remains limited. Drawing on social response theory and the technology acceptance model, this study aims to elucidate the adoption process of smart speakers.

A field survey of 391 smart speaker users were obtained. Partial least squares structural equation modeling was used to analyze the data.

Media richness (social cues) and parasocial interactions (social role) are key determinants affecting the establishment of trust, perceived usefulness and perceived ease of use, which, in turn, affect attitude, continuance usage intentions and online purchase intentions through AI assistants.

AI assistant-enabled smart speakers are revolutionizing how people interact with smart products. Studies of smart speakers have mainly focused on functional or technical perspectives. This study is the first to propose a comprehensive model from both functional and social perspectives of continuance usage intention of the smart speaker and online purchase intentions through AI assistants.