Development of techniques and technology for full polarimetric radar applied to concealed weapons detection

One of the biggest threats to modern society is the increasing use by criminals and terrorists of concealed weapons and person born improvised explosive devices (PBIED). Current highly mature security screening technologies using x-ray and metal detectors have limited deployment scenarios based on health and safety issues and operational range, respectively. Given that most clothing is greater than 90% transmissive in the microwave region, this spectral band is ideal for screening people for concealed threats. However, due to diffraction, imagery to screen subjects is limited due to the small number of pixels. In this regime, the exploitation of microwave polarimetry from the field of remote sensing has particular benefits, as it extracts maximum information content from a single pixel. The work presented in this thesis has assembled a full polarimetric frequency stepped radar from a vector network analyser (VNA), a linear orthogonal mode transducer (OMT) of the turnstile type and a conical corrugated horn antenna. The system’s characterisation by antenna pattern measurements, the measuring of canonical targets of the plane, dihedral, dipole and helical reflectors showed the system to be capable of making localised Sinclair matrix measurements of targets at ranges of two to three metres. The work presents a calibration procedure comprising the VNA’s internal calibration and an external calibration to compensate for dispersion and cross-polar leakage of system components. Static target measurements (canonical and various surrogate items) were analysed, using range gating for clutter rejection. Calibrated Sinclair parameter measurements compared with those from simple simulations, all software being programmed in Matlab. Measurements of moving targets revealed the phenomenon of speckle, this introducing rapid changes in the Sinclair Parameters. Data analysis performed using the coherency matrix and the Cloude/Pottier decomposition minimised the effects of speckle in the processed data. Measurements show movement from particularly rough surfaces increased the parameter of the Cloude/Pottier entropy, the level of this being directly linked to the degree of speckle. Application of the Huynen polarisation fork technique (a type of decomposition) has proved to aid the identification of static and moving targets. A detailed analysis of iii the Huynen fork responses is made of the human torso on its own, weapons on their own and then weapons positioned against the human torso. Responses of nondangerous objects such as keys and a smartphone are additionally presented

A Structure–Conduct–Performance Perspective of How Strategic Supply Chain Integration Affects Firm Performance

There are several factors that affect a firm\u27s ability to successfully integrate internally and externally for organizational improvement. This study seeks to understand the relationship between a firm\u27s strategy, its supply chain integration efforts, and firm performance. Leveraging the theoretical lens of structure–conduct–performance from the industrial organization economics literature, and utilizing both archival and survey data, we describe how firms may align their internal and external supply chain integration strategies with customers and suppliers. In doing so, these internal and external integration strategies affect the firm\u27s ability to respond to customer demand, which then impacts operational and financial performance. Our work provides theoretical and empirical evidence of these relationships and thus extends prior strategic supply chain integration literature

Full polarimetric millimetre wave radar for stand-off security screening

© COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only. The development and measurements are described of a frequency modulated continuous wave (FMCW) mono-static millimetre wave full polarimetric radar, operating at k-band (18 to 26 GHz). The system has been designed to explore the feasibility of using full polarimetry for the detection of concealed weapons, and person borne improvised explosive devices (PBIED). The philosophy of this scheme is a means to extract the maximum information content from a target which is normally in the single spatial pixel (sometimes sub-pixel) configuration in stand-off (tens of metres) and crowd surveillance scenarios. The radar comprises a vector network analyser (VNA), an orthomode transducer and a conical horn antenna. A calibration strategy is discussed and demonstrated using a variety of known calibration targets with known reflective properties, including a flat metal plate, dihedral reflector, metal sphere, helix and dipole. The orthomode transducer is based on a high performance linear polarizer of the turnstile type with isolation better than - 35dB between orthogonal polarisations. The calibration enables the polarimetric Sinclair scattering matrix to be measured at each frequency for coherent polarimetry, and this can be extended using multiple measurements via the Kennaugh matrix to investigate incoherent full polarimetry

Paraoxonase1 Genetic Polymorphisms in a Mixed Ancestry African Population

Paraoxonase 1 (PON1) activity is markedly influenced by coding polymorphisms, Q/R at position 192 and M/L at position 55 of the PON1 gene. We investigated the frequencies of these polymorphisms and their effects on PON1 and antioxidant activities in 844 South African mixed ancestry individuals. Genotyping was done using allele-specific TaqMan technology, PON1 activities were measured using paraoxon and phenylacetate, oxidative status was determined by measuring the antioxidant activities of ferric reducing antioxidant power and trolox equivalent antioxidant capacity, and lipid peroxidation markers included malondialdehyde and oxidized LDL. The frequencies of Q192R and L55M were 47.6% and 28.8%, respectively, and the most common corresponding alleles were 192R (60.4%) and 55M (82.6%). The Q192 was significantly associated with 5.8 units’ increase in PON1 concentration and 15.4 units’ decrease in PONase activity after adjustment for age, sex, BMI, and diabetes, with suggestion of differential effects by diabetes status. The PON1 L55 variant was associated with none of the measured indices. In conclusion, we have shown that the Q192R polymorphism is a determinant of both PON1 concentration and activity and this association appeared to be enhanced in subjects with diabetes

The Short-term Influence of a Mediterranean-type Diet and Mild Exercise with and without Red Wine on Patients with the Metabolic Syndrome

The metabolic syndrome is a target for the dietary prevention of cardiovascular disease. The effect of adding redwine to the diet has not been fully investigated. This study examined whether a Mediterranean-type dietcomplemented with red wine and mild exercise had an impact on patients with the metabolic syndrome in the shortterm. Twelve patients with the metabolic syndrome consumed a Mediterranean-type diet for four weeks withoutand with red wine respectively and performed mild exercise. We implemented the diagnostic criteria for themetabolic syndrome as formulated by the Adult Treatment Panel III (ATP III) in 2001. The patients were alsoscreened for multiple genetic markers implicated in cardiovascular disease. Weight, body mass index, abdominalcircumference and blood pressure were measured, as well as various biochemical, haematological andinflammatory markers. There was a significant decrease in the body weight (p = 0.04) and an increase in ORACvalue (p = 0.035) after the dietary intervention. A significant decrease in systolic blood pressure (p = 0.045) wasobserved. Red wine had no additional benefits. Although diet reduced weight and blood pressure, the lipoproteinand pro-coagulant profiles of patients with the metabolic syndrome were not affected in this study. These findingsmay be explained partly by the diverse genetic profile identified among the study participants, as 50% hadmutations involved in lipid metabolism that may influence the response to dietary intervention and alcoholconsumption

The influence of a Mediterranean Diet with and without Red Wine on the Haemostatic and Inflammatory Parameters of Subjects with the Metabolic Syndrome

This 8 week study examined whether a Mediterranean diet supplemented with red wine, had an acute impact onsubjects diagnosed with the metabolic syndrome. Twelve non-smoking subjects with diagnostic criteria of themetabolic syndrome on minimal medication, consumed a Mediterranean-like diet for 4 weeks respectively withoutand with red wine. The amount of red wine consumed was 250 ml (26 grams of alcohol) per day for male and 180ml (19 grams) per day for female participants. A nutrigenetic profile for cardiovascular risk factors was performedon each participant. Fasting blood specimens were taken at baseline, after the diet and after the diet with wineinterventions for platelet function, procoagulants FVII and FVIII, von Willebrand’s factor, fibrinogen, tissueplasminogen activator, plasminogen activator inhibitor-1, highly sensitive C-reactive protein and oxygen radicalabsorbance capacity (ORAC). After both periods of diet without wine and with wine, ORAC increased significantlycompared to baseline levels. Except for platelet H2O2 fluxes and FVII concentration, none of the haemostatic orinflammatory parameters changed significantly after the intervention periods compared with baseline levels.Genetic risk factors for cardiovascular disease were identified in all study participants and the potential genotypiceffects relevant to this study were generally in agreement with expected phenotypic response following the dietaryintervention. Our conclusions are that the period of intervention was too short for substantial changes inhaemostatic or in inflammatory parameters in subjects who already manifest some changes in their cardiovascularsystem and who showed diverse genetic profiles underlying increased cardiovascular risk

Design, development and verification of the 30 and 44 GHz front-end modules for the Planck Low Frequency Instrument

We give a description of the design, construction and testing of the 30 and 44 GHz Front End Modules (FEMs) for the Low Frequency Instrument (LFI) of the Planck mission to be launched in 2009. The scientific requirements of the mission determine the performance parameters to be met by the FEMs, including their linear polarization characteristics. The FEM design is that of a differential pseudo-correlation radiometer in which the signal from the sky is compared with a 4-K blackbody load. The Low Noise Amplifier (LNA) at the heart of the FEM is based on indium phosphide High Electron Mobility Transistors (HEMTs). The radiometer incorporates a novel phase-switch design which gives excellent amplitude and phase match across the band. The noise temperature requirements are met within the measurement errors at the two frequencies. For the most sensitive LNAs, the noise temperature at the band centre is 3 and 5 times the quantum limit at 30 and 44 GHz respectively. For some of the FEMs, the noise temperature is still falling as the ambient temperature is reduced to 20 K. Stability tests of the FEMs, including a measurement of the 1/f knee frequency, also meet mission requirements. The 30 and 44 GHz FEMs have met or bettered the mission requirements in all critical aspects. The most sensitive LNAs have reached new limits of noise temperature for HEMTs at their band centres. The FEMs have well-defined linear polarization characteristcs.Comment: 39 pages, 33 figures (33 EPS files), 12 tables. Planck LFI technical papers published by JINST: http://www.iop.org/EJ/journal/-page=extra.proc5/1748-022