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Penetrator plays an important role in the exploration of Moon and Mars. The navigation method is a key technology during the development of penetrator. To meet the high accuracy requirements of Moon penetrator, this paper aims to propose two kinds of navigation systems.

The line of sight of vision sensor between the penetrator and Moon orbiter could be utilized as the measurement during the navigation system design. However, the analysis of observability shows that the navigation system cannot estimate the position and velocity of penetrator, when the line of sight measurement is the only resource of information. Therefore, the Doppler measurement due to the relative motion between penetrator and the orbiter is used as the supplement. The other option is the relative range measurement between penetrator and the orbiter. The sigma-point Kalman Filtering is implemented to fuse the information from the vision sensor and Doppler or rangefinder. The observability of two navigation system is analyzed.

The sigma-point Kalman filtering could be used based on vision sensor and Doppler radar or laser rangefinder to give an accurate estimation of Moon penetrator position and velocity without increasing the payload of Moon penetrator or decreasing the estimation accuracy. However, the simulation result shows that the last method is better. The observability analysis also proves this conclusion.

Two navigation systems are proposed, and the simulations show that both systems can provide accurate estimation of states of penetrator.

Two navigation methods are proposed, and the observability of these navigation systems is analyzed. The sigma-point Kalman filtering is first introduced to the vision-based navigation system for Moon penetrator to provide precision navigation during the descent phase of Moon penetrator.

The purpose of this paper is to extend complex-shaped discrete element method simulations from a few thousand particles to millions of particles by using parallel computing on department of defense (DoD) supercomputers and to study the mechanical response of particle assemblies composed of a large number of particles in engineering practice and laboratory tests.

Parallel algorithm is designed and implemented with advanced features such as link-block, border layer and migration layer, adaptive compute gridding technique and message passing interface (MPI) transmission of C++ objects and pointers, for high performance optimization; performance analyses are conducted across five orders of magnitude of simulation scale on multiple DoD supercomputers; and three full-scale simulations of sand pluviation, constrained collapse and particle shape effect are carried out to study mechanical response of particle assemblies.

The parallel algorithm and implementation exhibit high speedup and excellent scalability, communication time is a decreasing function of the number of compute nodes and optimal computational granularity for each simulation scale is given. Nearly 50 per cent of wall clock time is spent on rebound phenomenon at the top of particle assembly in dynamic simulation of sand gravitational pluviation. Numerous particles are necessary to capture the pattern and shape of particle assembly in collapse tests; preliminary comparison between sphere assembly and ellipsoid assembly indicates a significant influence of particle shape on kinematic, kinetic and static behavior of particle assemblies.

The high-performance parallel code enables the simulation of a wide range of dynamic and static laboratory and field tests in engineering applications that involve a large number of granular and geotechnical material grains, such as sand pluviation process, buried explosion in various soils, earth penetrator interaction with soil, influence of grain size, shape and gradation on packing density and shear strength and mechanical behavior under different gravity environments such as on the Moon and Mars.

A severe breakage problem has been solved at Precision Propeller, Indianapolis, by using AerMet 100 alloy to make a shaft that holds propellers in place for straightening. The alloy is a high‐strength, high‐toughness steel developed by Carpenter Technology Corp., Reading, Pennsylvania.

The threat posed by nuclear weapons to world peace need not be exaggerated. Advancement in science and technology has enabled us to go for a complete annihilation of not only the Homo sapiens but all the species on earth. Should we permit our idiocy entangled with the nuclear weapons to destroy us or should we, the thinking animals, permit our wisdom to outlive the demonic nuclear weapons, is a question that is being asked by sensible people all over the world today. Just public denouncement of weapons of mass destruction is un-utilitarian. Mankind has been hearing such hollow, absurd words ever since the first atomic test. We have been feeding ourselves on a diet of hypocrisy. If it is not that what else is CTBT? Should the world permit demons to chant mantra? Isn’t it time to recognize that the world is governed not by saints but by Satans? (This is because rise and fall of civilizations has taught us that might is still right.) Isn’t it time to understand that only a metamorphosis of the Satans into saints can save the world? If we know that well, we should start thinking how the nuclear Satans could be transformed into nuclear saints and it is only logical that the nuke Satans should take initiative in transforming themselves, which alone would salvage the world. The present study is premised on these assumptions.

The purpose of this paper is to describe the initial stages of a year to 18 month project to design and produce a peer designed video game for teenagers for use across Derbyshire Libraries.

The context is set with an overview of educational games focusing on the UK experience before examining both commercial off the shelf and bespoke games in schools, universities and libraries in the USA and UK.

The paper posits a specification it is believed will result in a game which is both educational and fun.

Describes the initial development of a peer designed game for young people.