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Extrusion width, the width of printed filaments, affects multiple critical aspects in mechanical properties in material extrusion additive manufacturing: filament geometry, interlayer load-bearing bonded area and fibre orientation for fibre-reinforced composites. However, this study aims to understand the effects of extrusion width on 3D printed composites, which has never been studied systematically.

Four polymers with and without short-fibre reinforcement were 3D printed into single-filament-wide specimens. Tensile properties, mechanical anisotropy and fracture mechanisms were evaluated along the direction of extruded filaments (F) and normal to the interlayer bond (Z). Extrusion width, nozzle temperature and layer height were studied separately via single-variable control. The extrusion width was controlled by adjusting polymer flow in the manufacturing procedure (gcode), where optimisation can be achieved with software/structure design as opposed to hardware.

Increasing extrusion width caused a transition from brittle to ductile fracture, and greatly reduced directional anisotropy for strength and ductility. For all short fibre composites, increasing width led to an increase in strain-at-break and decreased strength and stiffness in the F direction. In the Z direction, increasing width led to increased strength and strain-at-break, and stiffness decreased for less ductile materials but increased for more ductile materials.

The transformable fracture reveals the important role of extrusion width in processing-structure-property correlation. This study reveals a new direction for future research and industrial practice in controlling anisotropy in additive manufacturing. Increasing extrusion width may be the simplest way to reduce anisotropy while improving printing time and quality in additive manufacturing.

One aspect of the growing issuance in catastrophe bonds is the increasing geographic diversity of coverage. Although catastrophe bonds initially focused on a single peril and territory, more recently they have been structured with independent multiple event triggers, differing according to peril and territory. This paper reviews the territorial development of catastrophe bonds and explores the geographical horizon for new issues.

We extend the Jones (1971) analysis of the effects of distortions in 2×2 trade models to the case of a two-sector dynamic general equilibrium model of a small open economy with capital accumulation. We do a comparative steady state analysis for the effect of policy changes on factor prices and the capital stock, and examine the dynamics of the system in the neighborhood of the steady state. We also show that the system will have multiple equilibria when value and physical factor intensity rankings of the sectors do not agree.

This study/paper aims to develop fundamental understanding of mechanical properties for multiple fibre-reinforced materials by using a single-filament-wide tensile-testing approach.

In this study, recently validated single-filament-wide tensile-testing specimens were used for four polymers with and without short-fibre reinforcement. Critically, this specimen construct facilitates filament orientation control, for representative longitudinal and transverse composite directions, and enables measurement of interlayer bonded area, which is impossible with “slicing” software but essential in effective property measurement. Tensile properties were studied along the direction of extruded filaments (F) and normal to the interlayer bond (Z) both experimentally and theoretically via the Kelly–Tyson model, bridging model and Halpin–Tsai model.

Even though the four matrix-material properties varied hugely (1,440% difference in ductility), consistent material-independent trends were identified when adding fibres: ductility reduced in both F- and Z-directions; stiffness and strength increased in F but decreased or remained similar in Z; Z:F strength anisotropy and stiffness anisotropy ratios increased. Z:F strain-at-break anisotropy ratio decreased; stiffness and strain-at-break anisotropy were most affected by changes to F properties, whereas strength anisotropy was most affected by changes to Z properties.

To the best of the authors’ knowledge, this is the first study to assess interlayer bond strength of composite materials based on measured interlayer bond areas, and consistent fibre-induced properties and anisotropy were found. The results demonstrate the critical influence of mesostructure and microstructure for three-dimensional printed composites. The authors encourage future studies to use specimens with a similar level of control to eliminate structural defects (inter-filament voids and non-uniform filament orientation).

The purpose of this paper is to present a clear path to securitize the longevity risk with two distinct swaps in order to inspire a new Chinese life market.

Studies on longevity risk securitization consist of three aspects, respectively, instrument design, pricing methodology and mortality projection. The swaps designed are referenced, respectively, to vanilla and complex survivor swaps (Dowd et al., 2006; Lin and Cox, 2005). Methods applied are RHH model and Gompertz law for mortality projection, as well as two-factor Wang transformation for pricing.

This paper figures out the market price of risk in Chinese annuity market, checks for the sensitivity of the price to parameters and tests the hedging effects by Monte Carlo simulation.

Based on the theoretical and numerical results, this paper suggests an effective way to possibly witness the birth of New Life Market in China.

THE fact that an English librarian was asked to describe the work of British municipal libraries, to audiences in Antwerp and Brussels, may be taken as a certain indication that a change is impending in the library world of Belgium. At the invitation of M. Frans Gittens, city librarian, Antwerp, acting on behalf of the Foundation for the Permanent Endowment of the Communal Library and Plantin‐Moretus Museum, and M. Paul Otlet, secretary‐general of the International Institute of Bibliography, Brussels, I had the honour and pleasure of lecturing on English library work and conditions to representative audiences greatly interested in the subject. This, it is understood, is the first time an English librarian has been invited to lecture on such a subject on any part of the Continent, and I certainly felt it a great honour and privilege to be thus selected for such a congenial task. The language difficulty was luckily no great bar, as most of my audiences, both Flemish and French, understood English quite well. In addition, the International Institute of Bibliography had printed a translation of the lecture, as No. 92 of its publications, and this was issued as a twenty‐two page pamphlet entitled Les Bibliothèques municipales en Angleterre, and distributed at Brussels. At Antwerp the programme also contained translations of the titles and remarks about the lantern slides, so that everything was made easy for one who has always deplored his inability to acquire the art of speaking foreign languages. As a further instance of the care and thoughtfulness exercised to provide for my comfort, I should acknowledge the kindness of M. Eugeen Everaerts, town librarian of Ostend, who, on representations from his colleague at Antwerp, met the steamer and passed me and my “projections” through the Custom House without trouble. There is no doubt that our Belgian friends have the knack of making strangers feel thoroughly at home. I am not likely to forget the kindness and hospitality of M. W. von Mallinckrodt, chairman of the Permanent Endowment Commission at Antwerp, who, with his charming wife, invited me to a lunch at which some of the chief residents were present, including Sir Cecil Hertslet, H.B.M. Consul‐General; Mr. Diedrich, the American Consul‐General; M. Henri Hymans, chief librarian of the Royal Library at Brussels; M. Max Rooses, of the Plantin Museum; M. Frans Gittens, with some members of his staff; and other gentlemen connected with the city and municipality of Antwerp. The same kindly hospitality was extended by M. Gittens, of Antwerp, and M. Otlet, at Brussels, and everything was done by all with whom I came in contact to make me feel at ease and nothing of a stranger. In fact it is impossible for anyone who has read Scott, Brontë and Conscience to feel like a stranger in Belgium. The lecture at Antwerp was given in the large and finely decorated hall of the Cercle Royal Artistique, Littéraire et Scientifique d'Anvers, a kind of general Arts Club combining the functions of places like the London Institution with those of an ordinary social club. The hall was capable of seating 1,000 persons, and was rather beyond my poor powers as an elocutionist. About 600 people attended, of whom a large number understood English, and my lecture, luckily for my audience, largely pictorial, was very well received. There was no preliminary introduction of any kind, and my “turn” came on after a concert had been about half heard. The following programme will give an idea of the kind of mixed entertainment which brought out 600 people on a snowy winter's afternoon:—

Weed control is essential in field vegetables but there has been a continual decline in the range of herbicides available. Growers aim to keep crops weed‐free throughout to maintain yield, but a short weed‐free period or even a single weeding can achieve the same result. In order to predict the optimum weeding period in advance, a realistic estimate is needed of the size, timing and duration of a flush of weed emergence in the crop. The weed seeds in the soil are the primary source of future weed populations, and this seedbank provides a unique resource for predictive management purposes. A preliminary model has been developed that combines information on the effect of burial depth of weed seeds on seedling emergence with a simulation of the incorporation and movement of seeds in soil following the use of different cultivation implements. The objective is to develop a suite of models which will provide a decision support system for weed control in field vegetables.

This paper aims to use a derivative of genetic programming to predict the bond strength of glass fiber-reinforced polymer (GFRP) bars in concrete under the effects of design guidelines. In developing bond strength prediction models, this paper prioritized simplicity and meaningfulness over extreme accuracy.

Assessing the bond strength of GFRP bars in concrete is a critical issue in designing and building reinforced concrete structures.

Ultimately, the equation of a linear form of a particular design guideline was suggested as the optimal prediction model. Improvements to the current design guidelines suggested by this model include setting a 1.31 magnification and considering the effects of the three significant parameters of bar diameter (db), minimum cover-to-bar diameter (C/db) and development length to bar diameter (l/db) under an acceptable root mean square error accuracy of around 2 MPa. Furthermore, the model suggests that the original influence parameter of concrete compressive strength (f_c) may be removed from bond strength calculations.

The model suggests that the original influence parameter of concrete compressive strength (f_c) may be removed from bond strength calculations.

A review of state‐of‐the‐art technology pertinent to tape automated bonding (for fine pitch, high I/O, high performance, high yield, high volume and high reliability) is presented. Emphasis is placed on a new understanding of the key elements (for example, tapes, bumps, inner lead bonding, testing and burn‐in on tape‐with‐chip, encapsulation, outer lead bonding, thermal management, reliability and rework) of this rapidly moving technology.

Based on an uncertainty model with an infinite horizon, this chapter analyzes how financial development and monetary policy in two countries can impact international trade and capital flows and influence individual behavior and welfare. Our study shows that differences in capital market development are the major contributing factors for trade imbalance and investment among countries. We also find that monetary policies are important factors affecting the trade balance, consumption, and investment. Countries with one-sided, pegging exchange rate policies tend to buy more bonds and enjoy larger trade surpluses. This effect is closely related to the level of capital market development: in these two countries, at higher stages of development, the effects of idiosyncratic monetary policy on imbalance are amplified.