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Two analytical solutions of thermal problems connected with the disposal of nuclear waste are presented. Non‐linear diffusion problems are analysed. The use of the Kirchhoff transformation and the transformation of coordinates are made along with a numerical solution. Also comparison is made for the exact and numerical solutions for temperature histories at a nuclear waste site. A time dependent heat source is considered.

The Kirchhoff transformation, in conjunction with the finite element method, is proposed as a tool in solving non‐linear heat conduction problems. A very simple way to obtain the inverse Kirchhoff transformation is shown, using the contour lines of the Kirchhoff variable obtained from a finite element analysis.

The purpose of this paper is to find analytic approximate solutions for time-dependent flow and heat transfer of a Sisko fluid.

The homotopy analysis method is used to find a family of travelling wave solutions of the governing non-linear problem.

The effects of different parameters on the velocity and temperature profiles are shown graphically.

The analytic solutions of the system of non-linear ordinary differential equations are constructed in the series form for various values of the power index.

The paper's aim is to investigate the mixed convection flow of an electrically conducting and viscous incompressible fluid past an isothermal vertical surface with Joule heating in the presence of a uniform transverse magnetic field fixed relative to the surface. It was assumed that the electrical conductivity of the fluid varies linearly with the transverse velocity component.

The governing boundary layer equations were solved numerically. The boundary layer equations were first reduced to a convenient form by using two different formulations, namely, (i) the stream function formulation (SFF) and (ii) primitive variable formulation (PVF).

It was observed that both the local shear‐stress and Nusselt number increase with increasing value of local magnetic parameter, ξ.

In the present investigation, we investigated the effects of Joule heating on MHD mixed convection boundary layer flow of an electrically conducting viscous incompressible fluid past an isothermal vertical flat plate in the presence of a transverse magnetic field fixed relative to the surface of the plate. The analysis was valid for a steady, two dimensional laminar flow. An extension to three dimensional flow case is left for future work.

Here we have analyzed the problem of mixed convection flow of electrically conducting and viscous incompressible fluid past an isothermal vertical surface with viscous and Joule heating in presence of a uniform transverse magnetic field fixed relative to the surface. The work would be useful in the thermal management of heat transfer devices.

The results of this study may be of interest to engineers interested in heat exchanger design.

The purpose of this paper is to study the adaptability of the tracked robot in complex working environment. It proposes an angle-changeable tracked robot with human–robot interaction in unstructured environment. The study aims to present the mechanical structure and human–robot interaction control system of the tracked robot and analyze the static stability of the robot working in three terrains, i.e. rugged terrain, sloped terrain and stairs.

The paper presents the mechanical structure and human–robot interaction control system of the tracked robot. To prevent the detachment of the tracks during obstacle navigation, a new type of passively adaptive device based on the relationship between the track’s variable angle and the forces is presented. Then three types of rough terrain are chosen to analyze the static stability of the tracked robot, i.e. rugged terrain, sloped terrain and stairs.

This paper provides the design method of the tracked robot. Owing to its appropriate dimensions, good mass distribution and limited velocity, the tracked robot remains stable on the complex terrains. The experimental results verify the effectiveness of the design method.

The theoretical analysis of this paper provides basic reference for the structural design of tracked robots.

The social sciences are really the “hard sciences” and the physical sciences are the “easy” sciences. One of the great contributors to making the job of the social scientist very difficult is the lack of fundamental dimensions on the basis of which absolute (i.e. ratio) scales can be formulated and in which relationships could be realized as the [allegedly] coveted equations of physics. This deficiency leads directly to the uses of statistical methods of various types. However it is possible, as shown, to formulate equations and to use them to obtain ratio/absolute scales and relationships based on them. This paper uses differential/integral equations, fundamental ideas from the processing view of the brain‐mind, multiple scale approximation via Taylor series, and basic reasoning some of which may be formulated as infinite‐valued logic, and which is related to probability theory (the theoretical basis of statistics) to resolve some of the basic issues relating to learning theory, the roles of nature and nurture in intelligence, the measurement of intelligence itself, and leads to the correct formulation of the potential‐actual type behaviors (specifically intelligence) and dynamical‐temporal model of intelligence development. Specifically, it is shown that the: (1) basic model for intelligence in terms of genetics and environment has to be multiplicative, which corresponds to a logical‐AND, and is not additive; (2) related concept of “genetics” creating its own environment is simply another way of saying that the interaction of genetics and environment is multiplicative as in (1); (3) timing of environmental richness is critical and must be modeled dynamically, e.g. in the form of a differential equation; (4) path functions, not point functions, must be used to model such phenomena; (5) integral equation formulation shows that intelligence at any time t, is a a sum over time of the past interaction of intelligence with environmental and genetic factors; (6) intelligence is about 100 per cent inherited on a global absolute (ratio) scale which is the natural (dimensionless) scale for measuring variables in social science; (7) nature of the approximation assumptions implicit in statistical methods leads to “heritability” calculations in the neighborhood of 0.5. and that short of having controlled randomized experiments such as in animal studies these are expected sheerely due to the methods used; (8) concepts from AI, psychology, epistemology and physics coincide in many respects except for the terminology used, and these concepts can be modeled nonlinearly.

Sediment measurement is usually accessible on a periodic or distinct basis. The measurement of sediment (suspended and bedload), especially in the field, is vital in keeping essential data of sediment transport and deposition. Various techniques for measuring sediment have been used over time each with its merits and demerits. The techniques discussed in this paper for suspended sediment include bottle, acoustic, pump, laser diffraction, nuclear and optical. Other techniques for bedload measurement are; River bedload trap (RBT), CSU/FU bedload trap, Helley–Smith, Polish Hydrological Services (PIHM) device, pit and trough, vortex tube, radioactive traces and bedload–surrogate technologies. However, the choice of technique depends on multiple factors ranging from budget constraint, availability of equipment, manpower and data requirement. The purpose of this paper is to present valuable information on selected techniques used in sediment measurement, to aid researchers/practitioners in the choice of sediment measurement technique.

This paper presents a general review of selected field techniques used in sediment measurement (suspended and bedload). Each techniques mode of operation, merits and demerits are discussed.

This paper highlights that each technique has its peculiar merits and demerits. However, two techniques are generally preferred over others; the bottle sampling and the Helley–Smith sampler for measuring suspended and bedload sediment. This is because the applicability of these techniques is quite widespread and time-tested.

This review paper provides an in-depth description and comparison of selected existing field sediment measurement techniques. The objective is to ease decision-making about the choice of technique, as well as to identify the suitability and applicability of the chosen technique.

We have from time to time suggested that librarians should pool experiences in regard to annual estimates, but there seems to be no enthusiasm for the suggestion. If library work is to develop it must be by gently progressive finance, and nothing helps one librarian more than to be able to point to another who is progressing. We all tend to wait upon one another. In such a matter as salaries, a librarian circulates his colleagues to learn what they are getting; and library authorities almost invariably ask, “What is paid at So and So ?” This is a vicious circle which cannot be broken unless librarians in consultation can reach a Standard. Perhaps the active London and Home Counties Branch of the L.A. will give a lead since the L.A. itself is too busy to do so.

Tom Bradley has never lived in a house with a bathroom. Born and bred in the Lancashire mill town of Accrington, he lives in the two‐up and two‐down type of terraced house spawned in their thousands across the face of Northern England in the aftermath of the industrial revolution. The stone‐built house, one of the scores clustered round a former mill, now converted into a dairy, faces on to a cobbled road and footpaths paved with slabs of hewn granite rather than the smooth concrete rectangles familiar to southern city dwellers. There are no trees in sight, no lawns, flowers or shrubs, no front gardens. The house is only one room wide; there is no provision for either a bathroom or a lavatory and there is no running water to either of the two bedrooms. The only lavatory is in a shed at the bottom of the back yard. It has no running water so there is no means of flushing it other than by taking a bucket of water from the house. The smell, summer and winter, is appalling.

OCCASIONALLY some writer is inspired to make the declaration that reference work as understood in America does not exist in Great Britain, or, even more definitely, is not known there. We rejoice at any advance our American friends make, but our enthusiasts for American methods must not undervalue the homeland. In the pages that follow some aspects of reference work receive attention, and the inference to be drawn may be that, if we have not specialized this department of work to the extent that transatlantic libraries have done, if in some smaller places it hardly exists “as the community's study, archive department and bureau of information,” yet in our larger cities and in many lesser places much work is done.