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This paper uses the long-span steel truss slab track as its research subject to analyze the new type of sleeper slab track structure with an experimental method. Firstly, a full-scale model was established in the laboratory to form a “rail–sleeper slab–self-compacting concrete cushion–steel beam” composite structure, and a fatigue test was performed on the track structure. The cyclic load was set up as a sine form with a range between 75 and 375 kN at a 5 Hz interval and 3 × 106 cycles. Based on the test, the performance of the track structure under cyclic train load was studied. Secondly, after every 106 loading cycles, the vertical static loading test and horizontal resistance test of the track structure were carried out to obtain the strain and displacement under different loading cycles. Finally, after 3 × 106 cycles of sine cyclic loading, the horizontal ultimate resistance test of the track structure was carried out to study its horizontal failure mode. The aims of this paper were to verify the applicability of the sleeper slab track, identify the mechanical properties, and determine the unfavorable position. The findings can provide an important reference for the practical use of the sleeper slab track structure.

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In this demo, we present an assembly of silver assistants for supporting Aging-In-Place (AIP). The virtual agents are designed to serve around the clock to complement human care within the intelligent home environment. Residing in different platforms with ubiquitous access, the agents collaboratively provide holistic care to the elderly users. The demonstration is shown in a 3-D virtual home replicating a typical 5-room apartment in Singapore. Sensory inputs are stored in a knowledge base named Situation Awareness Model (SAM). Therefore, the capabilities of the agents can always be extended by expanding the knowledge defined in SAM. Using the simulation system, we can rapidly conduct various types of experiments to test and evaluate whether the silver assistants have effectively and reliably fulfilled their duties when serving the elderly.

For ultra large ore carriers, springing response should be analyzed in the design stage since springing is the steady-state resonant vibration and has an important effect on the fatigue strength of hull structure. The springing response of a 550,000 DWT ultra large ore carrier has been studied by using experimental and numerical methods. A flexible ship model composed of nine segments was used in the experiment. The model segments were connected by a backbone with varying section, which can satisfy the request of natural frequency and stiffness distribution. The experiments in regular waves were performed and the motions and wave loads of the ship were measured. The experimental results showed that springing could be excited when the wave encounter frequency coincides with half or one-third the flexural natural frequency of the ship. In this paper, the analysis of the hydroelastic responses of the ultra large ore carrier was also carried out using a 3-D hydroelastic method. Comparisons between experimental and numerical results showed that the 3-D hydroelastic method could predict the motions and the vertical bending moments quite well. Based on this numerical method, the fatigue damage was estimated and the contribution of springing was analyzed.