The Integration of Laser Scanning and 3D Models in the Legal Process following an Industrial Accident

PublishedThis is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Background In order to obtain a deeper understanding of an incident, it needs to be investigated to "peel back the layers" and examine both the immediate and underlying failures that contributed to the event itself. One of the key elements of effective accident investigation is recording the scene for future reference. In recent years, however, there have been major advances in survey technology, which have provided the ability to capture scenes in 3D to an unprecedented level of detail, using laser scanners. Methods A case study involving a fatal incident was surveyed using 3D laser scanning and then subsequently recreated through virtual and physical models. The created models were then utilised in both the accident investigation and legal process top explore the technologies use in this setting. Results Benefits include; explanation of the event and environment, incident reconstruction, preservation of evidence, reducing the need for site visits, testing of theories. Drawbacks include; limited technology within court rooms, confusion caused by models, cost, personal interpretation and acceptance in the data. Conclusions The use of laser scanning surveys can be of considerable use in jury trials, for example, if the location supports the use of a high definition survey or if an object has be altered after the accident and has a specific influence on the case and needs to be recorded. However, consideration has to be made in its application and to ensure a fair trial, emphasis being placed on the facts of the case and personal interpretation controlled.The Authors would like to acknowledge the European Social Fund for providing funding for this research. In addition, the authors would also like to acknowledge 3DMSI Ltd for their assistance throughout this research

Electrostatic Patch Effect in Cylindrical Geometry. III. Torques

We continue to study the effect of uneven voltage distribution on two close cylindrical conductors with parallel axes started in our papers [1] and [2], now to find the electrostatic torques. We calculate the electrostatic potential and energy to lowest order in the gap to cylinder radius ratio for an arbitrary relative rotation of the cylinders about their symmetry axis. By energy conservation, the axial torque, independent of the uniform voltage difference, is found as a derivative of the energy in the rotation angle. We also derive both the axial and slanting torques by the surface integration method: the torque vector is the integral over the cylinder surface of the cross product of the electrostatic force on a surface element and its position vector. The slanting torque consists of two parts: one coming from the interaction between the patch and the uniform voltages, and the other due to the patch interaction. General properties of the torques are described. A convenient model of a localized patch suggested in [2] is used to calculate the torques explicitly in terms of elementary functions. Based on this, we analyze in detail patch interaction for one pair of patches, namely, the torque dependence on the patch parameters (width and strength) and their mutual positions. The effect of the axial torque is then studied for the experimental conditions of the STEP mission.Comment: 28 pages, 6 Figures. Submitted to Classical Quantum Gravit

A Measurement of Newton's Gravitational Constant

A precision measurement of the gravitational constant $G$ has been made using a beam balance. Special attention has been given to determining the calibration, the effect of a possible nonlinearity of the balance and the zero-point variation of the balance. The equipment, the measurements and the analysis are described in detail. The value obtained for G is 6.674252(109)(54) 10^{-11} m3 kg-1 s-2. The relative statistical and systematic uncertainties of this result are 16.3 10^{-6} and 8.1 10^{-6}, respectively.Comment: 26 pages, 20 figures, Accepted for publication by Phys. Rev.

Acceleration disturbances and requirements for ASTROD I

ASTRODynamical Space Test of Relativity using Optical Devices I (ASTROD I) mainly aims at testing relativistic gravity and measuring the solar-system parameters with high precision, by carrying out laser ranging between a spacecraft in a solar orbit and ground stations. In order to achieve these goals, the magnitude of the total acceleration disturbance of the proof mass has to be less than 10−13 m s−2 Hz−1/2 at 0.1 m Hz. In this paper, we give a preliminary overview of the sources and magnitude of acceleration disturbances that could arise in the ASTROD I proof mass. Based on the estimates of the acceleration disturbances and by assuming a simple controlloop model, we infer requirements for ASTROD I. Our estimates show that most of the requirements for ASTROD I can be relaxed in comparison with Laser Interferometer Space Antenna (LISA).Comment: 19 pages, two figures, accepted for publication by Class. Quantum Grav. (at press

Searching for galactic axions through magnetized media: QUAX status report

The current status of the QUAX R\&D program is presented. QUAX is a feasibility study for a detection of axion as dark matter based on the coupling to the electrons. The relevant signal is a magnetization change of a magnetic material placed inside a resonant microwave cavity and polarized with a static magnetic field.Comment: Contributed to the 13th Patras Workshop on Axions, WIMPs and WISPs, Thessaloniki, May 15 to 19, 201

Electrostatic Patch Effect in Cylindrical Geometry. I. Potential and Energy between Slightly Non-Coaxial Cylinders

We study the effect of any uneven voltage distribution on two close cylindrical conductors with parallel axes that are slightly shifted in the radial and by any length in the axial direction. The investigation is especially motivated by certain precision measurements, such as the Satellite Test of the Equivalence Principle (STEP). By energy conservation, the force can be found as the energy gradient in the vector of the shift, which requires determining potential distribution and energy in the gap. The boundary value problem for the potential is solved, and energy is thus found to the second order in the small transverse shift, and to lowest order in the gap to cylinder radius ratio. The energy consists of three parts: the usual capacitor part due to the uniform potential difference, the one coming from the interaction between the voltage patches and the uniform voltage difference, and the energy of patch interaction, entirely independent of the uniform voltage. Patch effect forces and torques in the cylindrical configuration are derived and analyzed in the next two parts of this work.Comment: 26 pages, 1 Figure. Submitted to Classical and Quantum Gravit

Observation of the thermal Casimir force

Quantum theory predicts the existence of the Casimir force between macroscopic bodies, due to the zero-point energy of electromagnetic field modes around them. This quantum fluctuation-induced force has been experimentally observed for metallic and semiconducting bodies, although the measurements to date have been unable to clearly settle the question of the correct low-frequency form of the dielectric constant dispersion (the Drude model or the plasma model) to be used for calculating the Casimir forces. At finite temperature a thermal Casimir force, due to thermal, rather than quantum, fluctuations of the electromagnetic field, has been theoretically predicted long ago. Here we report the experimental observation of the thermal Casimir force between two gold plates. We measured the attractive force between a flat and a spherical plate for separations between 0.7 $\mu$m and 7 $\mu$m. An electrostatic force caused by potential patches on the plates' surfaces is included in the analysis. The experimental results are in excellent agreement (reduced $\chi^2$ of 1.04) with the Casimir force calculated using the Drude model, including the T=300 K thermal force, which dominates over the quantum fluctuation-induced force at separations greater than 3 $\mu$m. The plasma model result is excluded in the measured separation range.Comment: 6 page

Analyzing Magnetically Induced Currents in Molecular Systems Using Current-Density-Functional Theory

A suite of tools for the analysis of magnetically induced currents is introduced. These are applicable to both the weak-field regime, well described by linear response perturbation theory, and to the strong-field regime, which is inaccessible to such methods. A disc-based quadrature scheme is proposed for the analysis of magnetically induced current susceptibilities, providing quadratures that are consistently defined between different molecular systems and applicable to both planar 2D and general 3D molecular systems in a black-box manner. The applicability of the approach is demonstrated for a range of planar ring systems, the ground and excited states of the benzene molecule, and the ring, bowl, and cage isomers of the C20 molecule in the presence of a weak magnetic field. In the presence of a strong magnetic field, the para- to diamagnetic transition of the BH molecule is studied, demonstrating that magnetically induced currents present a visual interpretation of this phenomenon, providing insight beyond that accessible using linear response methods

One-third of patients fail to return to work 1 year after surgery for colorectal cancer

Background Achieving full recovery after colorectal cancer surgery means a return to normal physical and psychological health and to a normal social life. Recovery data focusses on time to discharge rather than longer term functionality including return to work (RTW). We aim to assess return to normal holistic function at 1 year after colorectal cancer surgery. Method Questionnaires were created and dispatched to 204 patients who had undergone surgery with curative intent for colorectal cancer, in 2011–2012, in a single teaching hospital. Results Response rate was 75 % (153/204), 82 % (129/157) for open surgery (OS) and 51 % (24/47) for laparoscopic surgery (LS). Median age was 68 (48–91) years for OS and 65 (36–84) for LS. Eighty-four per cent of patients felt ‘ready’ and 95 % had adequate pain control upon discharge (no difference between groups). LS reported earlier ‘return to full fitness’ (1–3 months) than OS (>6 months; Mann–Whitney U, p < 0.05). Recovery from LS was ‘better than expected’ compared to OS ‘worse than expected’ (Mann–Whitney U test, p < 0.05). Forty-nine patients were employed preoperatively and 61 % (n = 30) returned to work. RTW was more frequent after LS (Chi-square test, p < 0.05). Length of time to RTW was significantly less after LS [44 (6–84) days] than OS [71 (14–252) days] (t test, p < 0.05). Levels of self-employment were equal between groups. Conclusions One-third of patients failed to RTW at 1 year post-surgery. Patients having LS returned to full fitness faster, felt recovery was shorter and returned to work earlier than OS. We must invest more in managing expectations and provide better post-discharge support to improve RTW