Trade-off between minimum number of wireless sensors and the accuracy of temperature profile in cold rooms: a model-based framework

Evaluation of temperature distribution in cold rooms is an important consideration in the design of food storage solutions. Two common approaches used in both industry and academia to address this question are the deployment of wireless sensors, and modelling with Computational Fluid Dynamics (CFD). However, for a realworld evaluation of temperature distribution in a cold room, both approaches have their limitations. For wireless sensors, it is economically unfeasible to carry out large-scale deployment (to obtain a high resolution of temperature distribution); while with CFD modelling, it is usually not accurate enough to get a reliable result. In this paper, we propose a model-based framework which combines the wireless sensors technique with CFD modelling technique together to achieve a satisfactory trade-off between minimum number of wireless sensors and the accuracy of temperature profile in cold rooms. A case study is presented to demonstrate the usability of the framework.

Model and visualise the relationship between energy consumption and temperature distribution in cold rooms

In the area of food and pharmacy cold storage, temperature distribution is considered as a key factor. Inappropriate distribution of temperature during the cooling process in cold rooms will cause the deterioration of the quality of products and therefore shorten their life-span. In practice, in order to maintain the distribution of temperature at an appropriate level, large amount of electrical energy has to be consumed to cool down the volume of space, based on the reading of a single temperature sensor placed in every cold room. However, it is not clear and visible that what is the change of energy consumption and temperature distribution over time. It lacks of effective tools to visualise such a phenomenon. In this poster, we initially present a solution which combines a visualisation tool with a Computational Fluid Dynamics (CFD) model together to enable users to explore such phenomenon.

Spatial and energetic mode dynamics of cold atomic systems

In this thesis we relate the formal description of various cold atomic systems in the energy eigenbasis, to the observable spatial mode dynamics. Herein the `spatial mode dynamics' refers to the direction of photon emission following the spontaneous emission of an excited fermion in the presence of a same species and spin ideal anisotropic Fermi sea in its internal ground state. Due to the Pauli principle, the presence of the ground state Fermi sea renders the phase space, anisotropic and only partially accessible, thereby a ecting the direction of photon emission following spontaneous emission. The spatial and energetic mode dynamics also refers to the quantum `tunneling' interaction between localised spatial modes, synonymous with double well type potentials. Here we relate the dynamics of the wavefunction in both the energetic and spatial representations. Using this approach we approximate the relationship between the spatial and energetic representations of a wavefunction spanning three spatial and energetic modes. This is extended to a process known as Spatial Adiabatic Passage, which is a technique to transport matter waves between localised spatial modes. This approach allows us to interpret the transport of matter waves as a signature of a geometric phase acquired by the one of the internal energy eigenstates of the system during the cyclical evolution. We further show that this geometric phase may be used to create spatial mode qubit and qutrit states.

Justifying jihad: US politics, propaganda and the Afghan mujahedeen

Hard-line anti-communists in the United States recognised the potential for the Soviet invasion of Afghanistan in 1979 to embroil their super-power rival in a ‘Vietnam-like quagmire.’ Their covert operation to arm the mujahedeen is well documented. This dissertation argues that propaganda and public diplomacy were powerful and essential instruments of this campaign. It examines the protagonists of this strategy, their policies, initiatives and programmes offering a comprehensive analysis heretofore absent. It stretches from the dying days of the Carter administration when Zbigniew Brzezinski saw the ‘opportunity’ presented by the invasion to the Soviet’s withdrawal in 1989. The aim of these information strategies was to damage Soviet credibility and enhance that of the US, considered under threat from growing ‘moral equivalence’ amongst international publics. The conflict could help the US regain strategic advantage in South Asia undermined by the ‘loss’ of Iran. The Reagan administration used it to justify the projection of US military might that it believed was eviscerated under Carter and emasculated by the lingering legacy of Vietnam. The research engages with source material from the Reagan Presidential Library, the United States Information Agency archives and the Library of Congress as well as a number of online archives. The material is multi-archival and multi-media including documentaries, booklets, press conferences, summit programmes and news-clips as well as national security policy documents and contemporaneous media commentary. It concludes that propaganda and public diplomacy were integral to the Reagan administration and other mujahedeen supporters’ determination to challenge the USSR. It finds that the conflict was used to justify military rearmament, further strategic aims and reassert US power. These Cold War machinations had a considerable impact on the course of the conflict and undermined efforts at resolution and reconciliation with profound implications for the future stability of Afghanistan and the world.