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THE article which we publish from the pen of Mr. L. Stanley Jast is the first of many which we hope will come from his pen, now that he has release from regular library duties. Anything that Mr. Jast has to say is said with originality even if the subject is not original; his quality has always been to give an independent and novel twist to almost everything he touches. We think our readers will find this to be so when he touches the important question of “The Library and Leisure.”

The purpose of this paper is to consider divergence of composite plate wings as well as slender wings with thin-walled cross-section of small-size airplanes. The main attention is paid to establishing of closed-form mathematical solutions for models of wings with coupling effects. Simplified solutions for calculating the divergence speed of wings with different geometry are established.

The wings are modeled as anisotropic plate elements and thin-walled beams with closed cross-section. Two-dimensional plate-like models are applied to analysis and design problems for wings of large aspect ratio.

At first, the equations of elastic deformation for anisotropic slender, plate-like wing with the large aspect ratio are studied. The principal consideration is delivered to the coupled torsion-bending effects. The influence of anisotropic tailoring on the critical divergence speed of the wing is examined in closed form. At second, the method is extended to study the behavior of the large aspect ratio, anisotropic wing with box-like wings. The static equations of the wing with box-like profile are derived using the theory of anisotropic thin-walled beams with closed cross-section. The solutions for forward-swept wing with box-like profiles are given in analytical formulas. The formulas for critical divergence speed demonstrate the dependency upon cross-sectional shape characteristics and anisotropic properties of the wing.

The following simplifications are used: the simplified aerodynamic theory for the wings of large aspect ratio was applied; the static aeroelastic instability is considered (divergence); according to standard component methodology, only the component of wing was modeled, but not the whole aircraft; the simplified theories (plate-lime model for flat section or thin-walled beam of closed-section) were applied; and a single parameter that defines the rotation of a stack of single layers over the face of the wing.

The simple, closed-form formulas for an estimation of critical static divergence are derived. The formulas are intended for use in designing of sport aircraft, gliders and small unmanned aircraft (drones). No complex analysis of airflow and advanced structural and aerodynamic models is necessary. The expression for chord length over the span of the wing allows for accounting a board class of wing shapes.

The derived theory facilitates the use of composite materials for popular small-size aircraft, and particularly, for drones and gliders.

The closed-form solutions for thin-walled beams in steady gas flow are delivered in closed form. The explicit formulas for slender wings with variable chord and stiffness along the wing span are derived.

This paper reports on a quasi-experimental research performed in the field of reading comprehension and translation quality. The purpose of this paper is to investigate the comparative effect of explicit vs implicit reading comprehension skills on translation quality of Iranian translation students at BA level.

The design of this research was quasi-experimental in nature. This design was preferred in this study, as it was impossible to assign random sampling to the subjects and apply a true experimental design. The research in hand was also a comparative group design research in a sense that it was supposed to compare two reading comprehension methods (explicit vs implicit) with different treatments.

In light of this research, some conclusions can be drawn. It can be concluded that there is a positive and direct relationship between reading comprehension and translation, as the first step of translation is to understand the content of the source text (Reid, 1993).

The reading comprehension ability of translation students should be enhanced in their undergraduate classes so that they can better understand the source text and produce a more fluent translation. In order to teach reading comprehension skills, both implicit and explicit techniques can be applied; however, it is better if the subjects receive explicit instruction, as this technique may have more positive results.

Various researchers have explored explicit and implicit instructions on such areas as reading, speaking and listening (see, e.g. Jalilifar and Alipour, 2007; Vahid Dastjerdi and Shirzad, 2010; Negahi and Nouri, 2014; Khanbeiki and Abdolmanafi-Rokni, 2015; Khoii et al., 2015; Mostafavi and Vahdany 2016; Rahimi and Riasati, 2017). Although the results of these studies have shown the positive impacts of both explicit and implicit teaching, explicit has more positive impacts. However, the review of the literature shows that explicit and implicit reading comprehension skills have not been investigated in relation to teaching translation and their possible impacts on translation quality.

The boundary element method has been used to obtain the electrical capacitances of the unit equilateral triangle, square, regular tetrahedron and cube. For each of these objects, a series of values of the number N of segments has been used and then empirical formulae have been used to extrapolate N to infinity. The singularities of the charge densities at the edges and corners of these objects can be characterised by power laws, the relevant exponents of which have also been determined.

VI.—OUT‐STATIONS IT has already been pointed out that the engineering maintenance department is a minor factor to the major factor of flying operations and, therefore, for maximum overall efficiency it may be necessary to run the engineering side of the work on a basis of over‐suitability. Admitting this state, it becomes expedient to arrange the work so that as little as possible is done by the more inefficient, i.e. the more over‐suitable, sections. Inefficiencies of the kind which will occur in the organization envisaged are caused principally by the necessity for rendering good service under conditions of peak load, and this entails the availability of labour and equipment in excess of normal requirements. This is particularly so at stations on the routes where aircraft stop for traffic and carry on according to a published schedule. The work done at such stations is principally refuelling, re‐oiling and perhaps some attention to cabin conditions. The personnel, however, must be prepared, and able, to attend to any complaint made by the pilot, or to do a daily inspection overnight with whatever preventative maintenance that may entail. In the case of larger aircraft, assistance may be rendered by the flight mechanic, though this assistance should not be counted upon to too great an extent, as the mechanic's flight duties may be heavy on that day or the next, and his alacrity should not be compromised by work which may demand his mental or physical labours during what should be his rest period.

ON January 12, 1966, the Royal Aeronautical Society celebrated its hundredth birthday with a Conversazione held at the Science Museum. Mr Fred Mulley, the Minister of Aviation, was among the many guests. As the oldest aeronautical society in the world it is the first to achieve the distinction of reaching its century.

The charge‐tube method is an accurate way of assigning the space‐charge of a beam in computational simulations of charged particle systems. The method is described and is compared with the traditional charge‐cell method.

Examines the methodological issues that arise in generating standardised transaction data for use in analysing the determinants of retail rents. Looks at the issues raised by the use of comparative information and the existence of widely accepted conventions for adjusting comparative evidence to allow for the specific physical and legal characteristics of individual properties. Concludes by questioning the need to test valuation convention against market evidence and the notion of open market value is reassessed.

The purpose of this paper is to study about the natural convection of water-based nanofluid in a partially open trapezoidal cavity under the influence of Brownian diffusion and thermophoresis.

Governing equations formulated in dimensionless stream function – vorticity variables – have been solved by finite difference method with a homemade code C++. Effects of Rayleigh number (Ra = 50-1,000), Lewis number (Le = 10-1,000), buoyancy-ratio parameter (Nr = 0.1-5.0), Brownian motion parameter (Nb = 0.1, 1.0) and thermophoresis parameter (Nt = 0.1, 1.0) on nanofluid flow and heat transfer have been studied.

It is found that high values of Rayleigh and Lewis numbers lead to the homogenization of nanoparticles distributions. For high values of Nt and Nb, heating is more essential and the cavity average temperature rises.

The originality of this work is to analyze natural convection in an open-sided trapezoidal cavity with Brownian diffusion and thermophoresis.

About 27 per cent of the total UK carbon emissions are attributed to residential buildings; therefore, improvements to the energy efficiency of the stock offers great potential. There are three main ways to achieve this. First is a mandatory approach, minimum energy efficiency standards are set and applied to new and existing buildings. Option 2 is voluntary, using energy ratings that classify performance to stimulate awareness and action. Third, financial measures, incentives and taxes, are applied to “nudge” behaviours. Most westernised countries have adopted a combination of Options 2 and 3, with the belief that the market will incentivize efficient properties. The belief is voluntary measures will stimulate demand, leading to value premiums. This paper aims to seek a deeper understanding of the relationship between energy efficiency and the value of residential property in Europe and, by so doing, to determine whether stronger policies are required to realise decarbonisation.

This paper reviews the current academic literature and large-scale quantitative studies conducted in Europe, mostly using hedonic pricing analysis to seek a relationship between energy performance certificates (EPCs) and either capital or rental values. It compares these to the reported findings of three case study projects that take a variety of different research approaches, all of which have the ambition to understand market behaviours and stimulate occupier or/and owner demand for energy efficient buildings.

The large-scale academic study results generally show a positive relationship between observed market prices and EPCs, which are commonly taken as surrogates for efficiency; however, outcomes are variable. One large study found energy upgrades may increase value, but not to the point where costs outweigh the value gain. Other studies found high returns on investment in energy efficiency technologies. The case study projects, however, revealed a more nuanced set of arguments in terms of the relationship between energy efficiency and market behaviours. Whilst there is some evidence that energy efficiency is beginning to impact on value, it is small compared to other value drivers; other drivers, including health, well-being and private sector finance deals, may prove more powerful market drivers. Further, the empirical findings reported point towards the emergence of a “brown” discount being more likely to be the long-term trend than a green premium. It is concluded that the current levels of action are unlikely to deliver the levels of decarbonisation urgently needed.

This is a desktop study of other European studies that may have collected data on slightly different variables.

This study shows that more action is required to realise decarbonisation in new and existing residential property in the European states considered. The sector offers potential for substantial reductions, and other mandatory approaches need to be considered.

This is a timely review of the current outcomes of European programmes (EPCs) adopted in several countries to increase energy efficiency in the residential sector through a voluntary mechanism. The results show that more action is needed.