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Boundary lubrication cannot provide long-term protection against scuffing. Therefore, it is fundamental to recognise the breaking point of the boundary layer that activates scuffing. Based on this assumption, three-dimensional (3D) morphologies of surfaces were characterised, and the fundamental conditions of the scuffing process were investigated to identify the transition from boundary lubrication conditions to catastrophic wear.

A series of systematic tribological double-blind experiments were carried out using a poorly lubricated cylinder/plane interface to model the tribological inverse problem in a boundary lubrication situation. Areal morphological analysis was performed, with the help of an optical interferometer, on a millimetric area corresponding to the contact surface during experimental tribological investigations. The statistical correlation between scuffing and the selected morphological parameters was evaluated. This evaluation study consisted of determining the linear, logarithmic, exponential, polynomial (of degree 2) or power dependency between time to scuffing and morphological parameters.

A clear, statistically confirmed relationship was observed between selected morphological parameters of the surface (Spd, Sha, Str, Sz) and its scuffing performance.

3D morphological parameters that best specified the technological scuffing performance of metallic surfaces were selected and proposed.

Dubai’s Electronic Transactions Law (“ETL”) is designed to stimulate E‐commerce in the emirate by improving the authenticity and integrity of electronic transactions. The ETL recognizes the legal validity of electronic documents and electronic signatures as acceptable substitutes for paper documents and ink signatures, respectively. Accordingly, electronic records may be used to comply with a statutory writing requirement, original document requirement and retention requirement, and an electronic signature attached to an electronic document may be used to comply with a statutory requirement for a paper‐and‐ink signature. If all parties are in agreement, a contract may be in electronic form and is just as legally enforceable as a written one. The ETL does not mandate Dubai’s governmental agencies to utilize electronic documents, but they may elect to do so. The ETL has created a compulsory system of licensing of Certification Authorities (“CA”). Their role is to ascertain the identity of a subscriber and to attest in an issued Certificate that the electronic signature used by that subscriber belongs to him. The ETL contains a list of computer crimes. The statute establishes a sound framework for E‐commerce, but it could be improved by adding consumer protections, more computer crimes, mandatory Egovernment, I.T. courts and long‐arm jurisdiction. The ETL’s exclusion of wills should be eliminated.

Only a day or two ago the Stars and Stripes were floating over the House of Lords and the invigorating “Battle Hymn of the Republic” was sung at St. Paul's in the presence of the King Emperor. The events were unique, and to all Britons happy in prophecy. English librarians have long admired their American brethren and their work; and of late they had read with regret the rather querulous remarks in at least one American library journal about the restrictions on book imports incidental to the blockade, and such phrases as “we have friends in both countries,” which gave the impression that our American friends failed to distinguish between the moral value of right and wrong in this world‐struggle. All this was intensified by the fact that every Briton in his heart believes the American to be of his own household, “to come of the blood,” and the want of understanding which we thought we detected was a particularly bitter thing. Of course this was a superficial view, and many of us realized how great was the sympathy between the English speaking races, and how difficult for the American the interracial problems of his country. Now, however, the air has been clarified, and the English librarian may look upon his American brethren as at one with himself in the struggle to preserve that freedom in the world which pervades the literature of our common language.

The paper's aim is to predict numerically the contact temperatures between two rough sliding bodies and to compare with the experimental results.

An elastic contact algorithm is used to analyze the normal contact between two nominally smooth surfaces. The algorithm evaluates real contact area using digitized roughness data and the corresponding contact pressure distribution. Using finite element method a steady state 3D temperature distribution at the interface between the sliding bodies is obtained. Using infrared (IR) imaging technique, experiments were carried out to measure the contact temperature distribution between rough rubbing bodies with a systematic variation of surface roughness and operating variables.

Contact temperature distributions over a wide range of normal load, sliding velocity and surface roughness have been obtained. It was seen that the maximum contact temperature expectedly increases with surface roughness (S_a values), normal load and sliding velocity. The results also indicate that the “hot spots” are located exactly at the positions where the contact pressures are extremely high. Temperatures can be seen to fall drastically at areas where no asperity contacts were established. The temperature contours at different depths were also plotted and it was observed that the temperatures fall away from the actual contact zone and relatively high temperatures persist at the “hot spot” zones much below the contact surface. Finally it is encouraging to find a good correlation between the numerical and experimental results and this indicates the strength of the present analysis.

Experimental accuracy can be improved by using a thermal imaging camera that measures emissivity in situ and uses it to find the contact temperature. The spatial resolution and the response time of the camera also need to be improved. This can improve the correlation between numerical and experimental results.

One of the major factors attributed to the failure of sliding components is the frictional heating and the resulting flash temperatures at the sliding interface. However, it is not easy to measure such temperatures owing to the inherent difficulties in accessing the contact zone. Besides, thermal imaging techniques can be applied only with such tribo‐pairs where at least one of the contacting materials is transparent to IR radiation. In practice, such cases are a rarity. However, the good correlation observed between the numerical and experimental results in this work would give the practicing engineer a confidence to apply the numerical model directly and calculate contact temperatures for any tribo‐material pairs that are generally seen around.

A good correlation between the numerical and experimental results gives credence to the fact that the numerical model can be used to predict contact temperatures between any sliding tribo‐pairs.