148 research outputs found

    Using acoustic sensor technologies to create a more terrain capable unmanned ground vehicle

    No full text
    Unmanned Ground Vehicle’s (UGV) have to cope with the most complex range of dynamic and variable obstacles and therefore need to be highly intelligent in order to cope with navigating in such a cluttered environment. When traversing over different terrains (whether it is a UGV or a commercial manned vehicle) different drive styles and configuration settings need to be selected in order to travel successfully over each terrain type. These settings are usually selected by a human operator in manned systems on what they assume the ground conditions to be, but how can an autonomous UGV ‘sense’ these changes in terrain or ground conditions? This paper will investigate noncontact acoustic sensor technologies and how they can be used to detect different terrain types by listening to the interaction between the wheel and the terrain. The results can then be used to create a terrain classification list for the system so in future missions it can use the sensor technology to identify the terrain type it is trying to traverse, which creating a more autonomous and terrain capable vehicle. The technology would also benefit commercial driver assistive technologie

    Design and development of a pole climbing surveillance robot

    No full text
    The cost of installing, monitoring and servicing a fixed camera system can be high and not all areas are in need of constant surveying. The increase in crime in urban areas emphasizes the need for a more effective and efficient surveillance system, as a result could lead to fewer crimes. A temporary surveillance unit which is able to climb to gain an elevated view has great potential for both military and civilian application. This paper highlights how the patent pending climbing robotic system (PC-101) was developed to be used by London’s Metropolitan Police Forensic Department for analysing outdoor crime scenes especially that related to car accidents. When cars are involved in accidents in the Metropolitan area, depending on the scale of the incident, the road generally has to be shut off to traffic if there are serious casualties. Elevated images are required for cases which may be taken to court, which then the images are then used as evidence, therefore regulations on the quality and perspectives of the image have to be met. By climbing a range of existing street furniture such as street lamp post, a temporary platform eliminates the use of larger special vehicle which struggles to get to the crime scene as well as cuts down the duration of the road closure. 98% of London street lamps in the Metropolitan area are constructed out of steel structures which make the use of magnetic wheels for locomotion an ideal solution to the climbing problem. Once remote controlled to the top of the lamp post, the PC-101 makes use of its actuated camera arm/gimbal to take the required shot, which can be seen on the ground control unit. A surveillance tool of this sort can be used for many applications which include crowd/riot control, crime scene investigations, monitoring hostile environments and even the monitoring of nature within urban environment

    Reconfigurable unmanned aerial vehicles.

    Get PDF
    Unmanned Aerial Vehicles (UAVs) have been developing dramatically due to wars and miniaturisation of technology, which has made the UAV industry a very lucrative business. Research organisations have been funded by various research committees or military groups to push UAV developments at a very fast pace. Although these UAVs are high in capability, they are limited to a single use application or mission. This paper will analyse current UAV systems to determine how the use of a novel reconfigurable UAV could benefit the end user

    Investigating the use of the coanda effect to create novel unmanned aerial vehicles.

    Get PDF
    In recent years the demand for Unmanned Aerial Vehicles(UAV's) has increased rapidly across many different industries and they are used for various applications. Such systems have the ability to enter dangerous or inaccessible environments and allow vital information to be collected without human risk. In order to carry out a task, a UAV has to face many different challenges. This has led to the development of novel platforms that move away from traditional aircraft design in order to make them more capable. A good example of this type of craft is one which uses the Coanda Effect to assist propulsion. This effect was discovered in 1930 by Henri-Marie Coanda who found that if a thin film of air is directed over a curved body, then the air follows the curve. When used to propel a UAV, the Coanda Effect also entrains air from above and lowers the air pressure in this region, which in turn generates more lift. Many organizations have attempted to use this phenomenon to aid the lift of various unusual air vehicles

    The future of battlefield micro air vehicle systems.

    Get PDF
    The most recent survey of Unmanned Aerial Vehicle (UAV) adoption rates shows that the area of small, man-portable systems (generally defined as Micro Air Vehicles or MAVs of maximum take-off weight between 1-5 kg) has one of the highest growth rates of any of the market sectors. There is a growing realisation by military planners that to win the insurgency wars of the present and future, forward units will have to operate within the close confines of urban conurbations and for prolonged periods of time without support. Real-time information and intelligence on enemy strength, dispositions and tactics is therefore essential for battlefield success

    Remarks on the diachronic reconstruction of intonational patterns in Romance with special attention to Occitan as a bridge language

    Get PDF
    This paper approaches Romance intonation from a diachronic point of view. The position that is adopted is that this is an area open to investigation. Comparative techniques can be fruitfully employed for investigating the evolution and diversification of the intonational patterns of the Romance languages. The focus of the paper is on Occitan. This is an important bridge language whose study may elucidate how French diverged prosodically from the systems found in Ibero and Italo-Romance. It is argued that, since Occitan was retained contrasts in the position of wordaccent (lexical stress), any prosodic features that French shares with Occitan are logically independent from the lack of contrastive accent in French

    An experimental human blood stage model for studying Plasmodium malariae infection

    Get PDF
    Background: Plasmodium malariae is considered a ‘minor’ malaria parasite, although its global disease burden is underappreciated. The aim of this study was to develop an induced blood stage malaria (IBSM) model of P. malariae to study parasite biology, diagnostics, and treatment. Methods: This clinical trial involved two healthy subjects who were intravenously inoculated with cryopreserved P. malariae-infected erythrocytes. Subjects were treated with artemether-lumefantrine following development of clinical symptoms. Prior to antimalarial therapy, mosquito feeding assays were performed to investigate transmission, and blood samples were collected for rapid diagnostic testing and parasite transcription profiling. Serial blood samples were collected for biomarker analysis. Results: Both subjects experienced symptoms and signs typical of early malaria. Parasitaemia was detected 7 days post-inoculation and increased until antimalarial treatment was initiated 25 and 21 days post-inoculation for Subject 1 and 2 respectively (peak parasitaemia levels were 174,182 and 50,291 parasites/mL respectively). The parasite clearance half-life following artemether-lumefantrine treatment was 6.7 hours. Mosquito transmission was observed for one subject, while in vivo parasite transcription and biomarkers were successfully profiled. Conclusions: An IBSM model of P. malariae has been successfully developed and may be used to study the biology, diagnostics, and treatment of this neglected malaria species

    Early-stage rifting of the northern Tyrrhenian Sea Basin: Results from a combined wide-angle and multichannel seismic study

    Get PDF
    Extension of the continental lithosphere leads to the formation of rift basins and ultimately may create passive continental margins. The mechanisms that operate during the early stage of crustal extension are still intensely debated. We present the results from coincident multichannel seismic and wide-angle seismic profiles that transect across the northern Tyrrhenian Sea Basin. The profiles cross the Corsica Basin (France) to the Latium Margin (Italy) where the early-rift stage of the basin is well preserved. We found two domains, each with a distinct tectonic style, heat flow and crustal thickness. One domain is the Corsica Basin in the west that formed before the main rift phase of the northern Tyrrhenian Sea opening (∼8–4 Ma). The second domain is rifted continental crust characterized by tilted blocks and half-graben structures in the central region and at the Latium Margin. These two domains are separated by a deep (∼10 km) sedimentary complex of the eastern portion of the Corsica Basin. Travel-time tomography of wide-angle seismic data reveals the crustal architecture and a subhorizontal 15–17 ± 1 km deep Moho discontinuity under the basin. To estimate the amount of horizontal extension we have identified the pre-, syn-, and post-tectonic sedimentary units and calculated the relative displacement of faults. We found that major faults initiated at angles of 45°–50° and that the rifted domain is horizontally stretched by a factor of β ∼ 1.3 (∼8–10 mm/a). The crust has been thinned from ∼24 to ∼17 km indicating a similar amount of extension (∼30%). The transect represents one of the best imaged early rifts and implies that the formation of crustal-scale detachments, or long-lived low-angle normal faults, is not a general feature that controls the rift initiation of continental crust. Other young rift basins, like the Gulf of Corinth, the Suez Rift or Lake Baikal, display features resembling the northern Tyrrhenian Basin, suggesting that half-graben formations and distributed homogeneous crustal thinning are a common feature during rift initiation

    Gabapentin for chronic pelvic pain in women (GaPP2): a multicentre, randomised, double-blind, placebo-controlled trial

    Get PDF
    Background: Chronic pelvic pain affects 2–24% of women worldwide and evidence for medical treatments is scarce. Gabapentin is effective in treating some chronic pain conditions. We aimed to measure the efficacy and safety of gabapentin in women with chronic pelvic pain and no obvious pelvic pathology. Methods: We performed a multicentre, randomised, double-blind, placebo-controlled randomised trial in 39 UK hospital centres. Eligible participants were women with chronic pelvic pain (with or without dysmenorrhoea or dyspareunia) of at least 3 months duration. Inclusion criteria were 18–50 years of age, use or willingness to use contraception to avoid pregnancy, and no obvious pelvic pathology at laparoscopy, which must have taken place at least 2 weeks before consent but less than 36 months previously. Participants were randomly assigned in a 1:1 ratio to receive gabapentin (titrated to a maximum dose of 2700 mg daily) or matching placebo for 16 weeks. The online randomisation system minimised allocations by presence or absence of dysmenorrhoea, psychological distress, current use of hormonal contraceptives, and hospital centre. The appearance, route, and administration of the assigned intervention were identical in both groups. Patients, clinicians, and research staff were unaware of the trial group assignments throughout the trial. Participants were unmasked once they had provided all outcome data at week 16–17, or sooner if a serious adverse event requiring knowledge of the study drug occurred. The dual primary outcome measures were worst and average pain scores assessed separately on a numerical rating scale in weeks 13–16 after randomisation, in the intention-to-treat population. Self-reported adverse events were assessed according to intention-to-treat principles. This trial is registered with the ISRCTN registry, ISCRTN77451762. Findings: Participants were screened between Nov 30, 2015, and March 6, 2019, and 306 were randomly assigned (153 to gabapentin and 153 to placebo). There were no significant between-group differences in both worst and average numerical rating scale (NRS) pain scores at 13–16 weeks after randomisation. The mean worst NRS pain score was 7·1 (standard deviation [SD] 2·6) in the gabapentin group and 7·4 (SD 2·2) in the placebo group. Mean change from baseline was −1·4 (SD 2·3) in the gabapentin group and −1·2 (SD 2·1) in the placebo group (adjusted mean difference −0·20 [97·5% CI −0·81 to 0·42]; p=0·47). The mean average NRS pain score was 4·3 (SD 2·3) in the gabapentin group and 4·5 (SD 2·2) in the placebo group. Mean change from baseline was −1·1 (SD 2·0) in the gabapentin group and −0·9 (SD 1·8) in the placebo group (adjusted mean difference −0·18 [97·5% CI −0·71 to 0·35]; p=0·45). More women had a serious adverse event in the gabapentin group than in the placebo group (10 [7%] of 153 in the gabapentin group compared with 3 [2%] of 153 in the placebo group; p=0·04). Dizziness, drowsiness, and visual disturbances were more common in the gabapentin group. Interpretation: This study was adequately powered, but treatment with gabapentin did not result in significantly lower pain scores in women with chronic pelvic pain, and was associated with higher rates of side-effects than placebo. Given the increasing reports of abuse and evidence of potential harms associated with gabapentin use, it is important that clinicians consider alternative treatment options to off-label gabapentin for the management of chronic pelvic pain and no obvious pelvic pathology. Funding: National Institute for Health Research

    Antiglucocorticoid RU38486 reduces net protein catabolism in experimental acute renal failure

    Get PDF
    BACKGROUND: In acute renal failure, a pronounced net protein catabolism occurs that has long been associated with corticoid action. By competitively blocking the glucocorticoid receptor with the potent antiglucocorticoid RU 38486, the present study addressed the question to what extent does corticoid action specific to uremia cause the observed muscle degradation, and does inhibition of glucocorticoid action reduce the protein wasting? METHODS: RU 38486 was administered in a dose of 50 mg/kg/24 h for 48 h after operation to fasted bilaterally nephrectomized (BNX) male adult Wistar rats and sham operated (SHAM) controls. Protein turnover was evaluated by high performance liquid chromatography (HPLC) of amino acid efflux in sera from isolated perfused hindquarters of animals treated with RU 38486 versus untreated controls. RESULTS: Administration of RU 38486 reduces the total amino acid efflux (TAAE) by 18.6% in SHAM and 15.6% in BNX and efflux of the indicator of net protein turnover, phenylalanine (Phe) by 33.3% in SHAM and 13% in BNX animals as compared to the equally operated, but untreated animals. However, the significantly higher protein degradation observed in BNX (0.6 ± 0.2 nmol/min/g muscle) versus SHAM (0.2 ± 0.1 nmol/min/g muscle) rats, as demonstrated by the marker of myofribrillar proteolytic rate, 3-Methylhistidine (3 MH) remains unaffected by administration of RU 38486 (0.5 ± 0.1 v. 0.2 ± 0.1 nmol/min/g muscle in BNX v. SHAM). CONCLUSION: RU 38486 does not act on changes of muscular protein turnover specific to uremia but reduces the effect of stress- stimulated elevated corticosterone secretion arising from surgery and fasting. A potentially beneficial effect against stress- induced catabolism in severe illness can be postulated that merits further study
    corecore