560 research outputs found

    Investigations into the optimisation of sound suppressor geometry

    Get PDF
    Health and Safety regulations are becoming ever more stringent in order to protect us in all aspects of our daily lives to prevent noise pollution and damage to hearing. For those in the military and some areas of civilian life working with firearms there is a definite need to reduce the sound levels from them. In order to do this a working knowledge of sound moderators and suppressors is considered vital in order to assess their capabilities and optimise their performance. The project looks at a theoretical model of an integral suppressor for a modified 12 bore shotgun. The model was used to determine the area of holes through the barrel, allowing gas into the suppressor, has the greatest effect on the pressure within the suppressor. It was found that the volume of the suppressor and position of the hole through the barrel did not have such a significant effect on the pressure. The theoretical work was supported by experimental trials which confirmed the barrel hole size has a significant effect on the pressure. The experimental work also showed for the low pressure system the hole size through the baffles did not have a significant effect on the pressure. Work was carried out to establish whether current practice for proofing suppressors was sufficient. The results show that proof rounds give a lower pressure in an external suppressor than standard ammunition. Tests on improvised suppressors showed they are effective and allowed a visual analysis on suppressors. Baffles were shown to be advantageous in a suppressor configuration.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Kinetic energy less lethal weapons and their associated blunt trauma injuries

    Get PDF
    A widely used class of Less Lethal Weapon is the kinetic energy projectile. This can cause blunt trauma to the targeted person and, under certain circumstances, its use can result in permanent injury or death. The low velocity at which Less Lethal projectiles are launched results in inaccuracy of use thus increasing the possibility that non targeted areas of the body susceptible to injury by blunt trauma will be hit. This research has been focused to investigate the impact characteristics of kinetic energy Less Lethal projectiles using different masses, materials, geometries and impact velocities and how they affect the criteria for injury to the head and the thorax. Computer based models for simulating impacts and possible injuries were investigated. Hydro codes were used to predict the effect of a range of projectile masses and impact velocities for a simplified human target. Physical models were built and tested to compare with the computer predictions. A correlation between projectile mass, velocity and skin penetration was found. Research was carried out on the impact process using an instrumented projectile to measure the acceleration experienced by the projectile and the duration of acceleration for a range of target materials. A simulated head model with a displacement transducer was used to investigate the impact properties of a range of projectile geometries with the objective of identifying the probable effect on blunt trauma and the level of injury that may be sustained. The introduction of air cavities into the projectile reduced the recorded displacement as well as its acceleration whilst extending the duration of the impact. High-speed video was used to investigate the impact process between the projectile and the target using a simulated thorax. The target used was a Behind Armour Blunt Trauma (BABT) test rig originally developed to investigate behind armour blunt trauma associated with combat body armour impacted by high velocity projectiles. A wide range of projectile geometries, materials and masses were investigated to examine the probable effect on blunt trauma and the level of injury that may be sustained. The introduction of air cavities and reduction of projectile mass was found to slightly reduce the rate of displacement in the BABT rig; however the maximum displacement remained similar because of the similar masses and velocities involved.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Research activities arising from the University of Kent

    Get PDF
    In this paper I describe research activities in the field of optical fiber sensing undertaken by me after leaving the Applied Optics Group at the University of Kent. The main topics covered are long period gratings, neural network based signal processing, plasmonic sensors, and polymer fiber gratings. I also give a summary of my two periods of research at the University of Kent, covering 1985–1988 and 1991–2001

    Idylls of socialism : the Sarajevo Documentary School and the problem of the Bosnian sub-proletariat

    Get PDF
    This historical overview of the Sarajevo Documentary School considers the films, in the light of their recent re-emergence, as indicative of both the legacy of socialist realism (even in the context of Yugoslav media) and attempted social engineering in the Bosnia of the 1960s and 1970s. The argument is made that the documentaries, despite their questionable aesthetic status (in respect of cinma-vrit and ethnography) and problematic ideological strategies and attempted interventions, document a history and offer insights that counter the prevailing revisionist trends in the presentation of Eastern and Central European history

    From capability to concept : fusion of systems analysis techniques for derivation of future soldier systems

    Get PDF
    The intent of this thesis is to define a set of processes for use within UK Government dismounted soldier systems research that will provide stakeholders with auditable and traceable information to understand gaps in military capability and justify future procurement decisions. The need for this approach is linked to organisational shifts within the UK Ministry of Defence, and more specifically Government research with the move towards procurement of capability rather than equipment. In conjunction with reducing defence budgets and increased scrutiny, there is a need to prioritise spending to those areas that will provide the most significant enhancement to operational effectiveness. The proposed process suite provides underpinning data to support Government decisions, from definition of military need through to concept design and prioritisation of future research activities. The approach is grounded in the field of systems thinking and systems engineering providing the logical and systematic constructs required for highly complex systems where the human is a central focus. A novel fusion of existing systems tools and techniques enables both subjective data from domain experts and objective data in the form of operational analysis and field trials to be utilised for analysis across the five NATO capability domains, with output defining the relative importance of survivability, sustainability, mobility, lethality and C4I in the context of operational and strategic level military goals as well as wider challenges represented by the doctrinal defence lines of development. Future developments should include alignment with developing pan-MoD initiatives in the form of MODAF, if required by the customer organisation. This would enable generic versions of the process suite to be applied to any defence domain and problem.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Systems for electronic documentation and sharing of advance care planning preferences: a scoping review

    Get PDF
    Digital approaches to support advance care planning (ACP) documentation and sharing are increasingly being used, with a lack of research to characterise their design, content, and use. This study aimed to characterise how digital approaches are being used to support ACP documentation and sharing internationally. A scoping review was performed in accordance with the JBI (formerly Joanna Briggs Institute) guidelines and the PRISMA 2020 checklist, prospectively registered on Open Science Framework (https://osf.io/xnrg3). MEDLINE, EMBASE, PsycINFO, ACM Digital, IEEE Xplore and CINAHL were searched in February 2023. Only publications in English, published from 2008 onwards were considered. Eligibility criteria included a focus on ACP and electronic systems. Out of 2,393 records, 34 reports were included, predominantly from the USA (76.5%). ACP documentation is typically stored in electronic health records (EHRs) (67.6%), with a third (32.4%) enabling limited patient access. Non-standard approaches (n = 15;44.1%) were the commonest study design of included reports, with outcome measures focusing on the influence of systems on the documentation (i.e. creation, quantity, quality, frequency or timing) of ACP information (n = 23;67.6%). Digital approaches to support ACP are being implemented and researched internationally with an evidence base dominated by non-standard study designs. Future research is needed to extend outcome measurement to consider aspects of care quality and explore whether the content of existing systems aligns with aspects of care that are valued by patients

    The role, impact, and support of informal caregivers in the delivery of palliative care for patients with advanced cancer: A multi-country qualitative study

    Get PDF
    Background: Cancer is increasing in its prevalence in sub-Saharan Africa. Informal caregivers are key to supporting engagement and interaction with palliative care services, but limited literature on their role impedes development of supportive interventions. Aim: We aimed to understand the role, impact, and support of informal caregivers of patients with advanced cancer when interacting with palliative care services in Nigeria, Uganda, and Zimbabwe. Design: Secondary analysis of qualitative interview transcripts. The dataset was assessed for fit and relevance and framework approach was used. Setting/participants: Interview transcripts of informal caregivers included participants aged over 18 years of age recruited from palliative care services across participating countries. Results: A total of 48 transcripts were analyzed. Mean age was 37 (range 19–75) with equal numbers of men and women. Five themes emerged from the data: (1) caregivers are coordinators of emotional, practical, and health service matters; (2) caregiving comes at a personal social and financial cost; (3) practical and emotional support received and required; (4) experience of interacting and liaising with palliative care services; and (5) barriers and recommendations relating to the involvement of palliative care. Conclusions: The role of informal caregivers is multi-faceted, with participants reporting taking care of the majority of medical, physical, financial, and emotional needs of the care recipient, often in the face of sacrifices relating to employment, finances, and their own health and social life. Efforts to develop comprehensive cancer control plans in sub-Saharan Africa must take account of the increasing evidence of informal caregiver needs

    Oncology distress screening within predominately Black Veterans: Outcomes on supportive care utilization, hospitalizations, and mortality

    Get PDF
    Background We evaluated whether patients' initial screening symptoms were related to subsequent utilization of supportive care services and hospitalizations, and whether patient-level demographics, symptoms, hospitalizations, and supportive care service utilization were associated with mortality in primarily low-income, older, Black Veterans with cancer. Methods This quality improvement project created collaborative clinics to conduct cancer distress screenings and refer to supportive care services at an urban, VA medical center. All patients completed a distress screen with follow-up screening every 3 months. Supportive care utilization, hospitalization rates, and mortality were abstracted through medical records. Poisson regression models and cox proportional hazard models were utilized. Results Five hundred and eighty five screened patients were older (m = 72), mostly Black 70% (n = 412), and had advanced cancer 54%. Fifty-eight percent (n = 340) were screened only once with 81% (n = 470) receiving ≥1 supportive care service and 51.5% (n = 297) being hospitalized ≥1 time 18 months following initial screen. Symptom severity was significantly related to number of hospitalizations. Low mood was significantly related to higher supportive services (p < 0.001), but not hospitalizations (p ≥ 0.52). Pain, fatigue, physical function, nutrition, and physical symptoms were significantly associated with more supportive services and hospitalizations (p < 0.01). Twenty percent (n = 168) died; Veterans who were Black, had lower stage cancers, better physical health, and utilized less supportive care services had lower odds of mortality (p ≤ 0.01). Conclusion Individuals with elevated distress needs and those reporting lower physical function utilized more supportive care services and had higher hospitalization rates. Lower physical function, greater supportive care use, higher stage cancer, and being non-Black were associated with higher odds of death
    corecore