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May 10, 1966 Building — Safety regulations — Guard‐rails — Outside staircase — Guard‐rail three feet above stairs — Plaintiff's fall over side under rail — Purpose of guard‐rails to provide effective physical barrier — Whether one guard‐rail “suitable” — Building (Safety, Health and Welfare) Regulations, 1948 (S. I. 1948 No. 1145), reg. 27(2)(a).

THE application of scientific principles to the design of aircraft and aircraft equipment during the post‐war years has yielded results which are becoming increasingly apparent. The time interval which elapses between the conception of an idea and its application to production aircraft is necessarily long, but it would seem that we are just beginning to reap the reward of much patient study.

This paper provides a few examples of techniques that are being used at the Thornton Research Centre of “Shell” Research Limited in the development of lubricants. No attempt has been made to provide a detailed description of how the techniques were developed or how they are used. For some of them detailed information is already available in published articles or papers, and references are provided; others are still in the development stage and more information will probably be published at some later date. It will be obvious that to attempt to cover any one of these developments in detail would require much more time than is either at your disposal or mine, and I have therefore given only sufficient detail to perhaps whet your appetites for more. Typical of the sorts of information required for lubricant development are the following :— 1. Accurate temperature measurements of the moving and/or contacting and rubbing surfaces of the mechanism to be lubricated. 2. A qualitative or quantitative assessment of surface damage of contacting or rubbing parts. 3. An accurate measurement of wear rate. 4. An accurate measurement of the chemical change occurring on the surface of rubbing components in the presence of E.P. additives. This list could be extended almost indefinitely but it provides a fair cross‐section of the type of information likely to be required for the development of a lubricant. This sort of information must often be obtained from simulated mechanisms specially instrumented and designed, but we are designing lubricants for actual mechanism, gear trains, transmissions, bearings, clutch plates, etc., where it is extremely rare to find provision or access for the qualitative and/or quantitative examination so desired. As a result very elaborate and complicated methods have sometimes to be employed to obtain the necessary information. The following techniques represent only a few of those that have been used or are being used, but I hope they will demonstrate how some of our difficulties ware overcome.

TO those who properly understand the effect on industrial production of efficient lighting, it has come as no surprise that the Departmental Committee on lighting in factories has recommended a new standard of intensities. The fact remains, however, that many installations have been automatically rendered out‐of‐date. For this reason factory executives of works engaged on all manner of processes have to face the problem of modernizing their lighting schemes and are consequently seeking guidance on the accomplishment of this object in the most expeditious, efficient and economic manner.

Natural gas (NG) consumption is increasing at an alarming rate, and more than 50 percent of this gas is used in generating electric power (EP) and desalted seawater (DW) in what is called cogeneration power desalting plants (CPDP). In this context, the purpose of this paper is to study the energy status in Qatar. More specifically, Qatar energy supply side is studied through the CPDP. In an effort to decrease the energy consumption by raising the efficiency of the CPDP (at the supply side), and conserving energy at the demand side, primarily energy footprint is performed.

The status of CPDP, in terms of the type, capacity, fuel consumption is studied, and measures that should be taken to improve their performance and reduce their consumed fuel are presented.

Study of the EP and DW sector showed that the fuel consumed in the CPDP can be reduced substantially by converting the simple gas turbine cycle to combined cycle to raise its efficiency from 30 percent to up to 50 percent. On the demand side, it was shown that air conditioning (AC) of buildings consumes about two‐third of the summer peak load; and about half of the annual EP output. So, measures to decrease the AC cooling load are suggested by implementing building code to decrease the consumed energy in buildings.

Data on the NG and oil proven reserve, production, and consumption are limited and scattered. It is necessary to have a clear picture of Qatar showing the flow of energy supply, demand, consumption, and losses in certain sectors to know where energy can be conserved; and this paper is the first trial in that direction. Although prime energy looks abundant today, it can be consumed locally within few decades if consumption is not controlled.

THE new De Havilland Gipsy Major 130 h.p. aero‐engine designed by Major V. B. Halford is of the inverted air‐cooled four‐cylinder in‐line type.

The aim of the paper is to extend and update previous research carried out in the period immediately following the unification of Germany in 1990. This period saw a rapid and substantial movement by (West) German retailers into the former German Democratic Republic. The paper examines, though a tracking study of the top German retailers, the status of those retailers some years on in terms of the extent to which they have assimilated their operations in eastern Germany and now regard them as merely a part of a united Germany. More importantly, the paper examines the extent to which the moves into the former East Germany have been used as a springboard to expansion in the former socialist states of central and eastern Europe in a period that has seen substantial and significant consolidation among German retailers.

The purpose of this study is to test a chassis robot on rugged road cargo handling.

Attitude solution of D-H series robot gyroscope speed and acceleration sensor.

In identical experimental environments, hexapodal robots experience smaller deviations when using a four-footed propulsive gait from a typical three-footed gait for forward motion; for the same distance but at different speeds, the deviation basically keeps itself within the same range when the robot advances forward with four-foot propulsive gait; because the foot slide in the three-footed gait sometimes experiences frictions, the robot exhibits a large gap in directional deviations in different courses during motion; for motion using a four-footed propulsive gait, there are minor directional deviations of hexapodal robots resulting from experimental errors, which can be reduced through optimizing mechanical structures.

Planning different gaits can solve problems existing in some typical gaits. This article has put forward a gait planning method for hexapodal robots moving forward with diverse gaits as a redundant multifreedom structure. Subsequent research can combine a multiparallel-legged structure to analyze kinematics, optimize the robot’s mechanical structure and carry out in-depth research of hexapod robot gaits.

Planning and control of humanoid biped walking has been an active research topic for many years. But, there is no definite answer to the question of how to practicre‐examinedally achieve speedy and stable walking in real‐time and in a changing environment. The purpose of this paper is to re‐examine the issue of planning and controlling humanoid biped walking, then to propose two new ideas.

The first idea is to treat the supporting foot of a biped to be part of the ground. In this way, there is a foot reaction force acting at a fixed virtual joint, which can be at, or below, the ankle joint. And, a new concept is come our that is named as in‐foot ZMP in contrast to the existing concept of on‐ground ZMP. The unique benefit with this new concept of in‐foot ZMP is that the ZMP control is no longer an issue because the in‐foot ZMP can be controlled so as to to be at a fixed virtual joint during a stable walking. Such a fixed virtual joint can be called a ZMP joint.

The second idea is to focus on hip's trajectory (instead of on‐ground ZMP's trajectory) and to split a hip's dynamic response into two independent parts: one is the steady‐state response contributing to the stability of walking (or standing), and the other is the transient response contributing to the speed of walking. This idea allows us to explicitly postulate the necessary and sufficient condition for achieving leg stability as well as the necessary and sufficient condition for achieving foot stability. The paper shows that the implementation of these two new ideas help realize a unified framework for task‐guided, intention‐guided, and sensor‐guided, planning and control of humanoid biped walking.

This paper first re‐examines the issue of planning and controlling humanoid biped walking, then proposes two new ideas. The first idea is to treat the supporting foot of a biped to be part of the ground. The second idea is to focus on hip's trajectory (instead of on‐ground ZMP's trajectory) and to split a hip's dynamic response into two independent parts: one is the steady‐state response contributing to the stability of walking (or standing), and the other is the transient response contributing to the speed of walking.

Jumping robots with coordinated multiple legs have been a hot research subject during the past years because of their excellent abilities in fast moving and obstacle-climbing. However, dynamics of jumping process of these coordinated legged robots are complex because of collisions between coordinated legs and the ground. This paper aims to analyze features of jumping process and to present the kinematic and dynamic models of a novel sole-type quadruped jumping robot with variable coordinated joints.

A complete jumping period of is divided into several subphases according to contact status of different coordinated legs to the ground. Continuous dynamics and discrete dynamics are established in different subphases. Simulations are performed in MATLAB software and ADAMS environment.

Comparison between two-set simulated results acquired from ADAMS and MATLAB demonstrates the validity of kinematic and dynamic equations.

The established dynamics establish the foundation of further research in motion planning and controller design of coordinated multiple legs.