Investigations into the optimisation of sound suppressor geometry

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

Research activities arising from the University of Kent

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

What are the Prospects of 3D Profiling Systems Applied to Firearms and Toolmark Identification?

This paper details a comparative pilot study of 3D (three dimensional) imaging technologies for potential application in forensic firearms and toolmark identification; as such it reviews the most up-to-date profiling systems. In particular, the paper focuses on the application of 3D imaging and recording technology as applied to firearm identification, being a specialised field within the discipline of toolmark identification. Each technology under test employs a different technique or scientific principle to capture topographic data i.e. focus-variation microscopy, confocal microscopy, point laser profilometry and vertical scanning interferometry. To qualitatively establish the capabilities and limitations of each technology investigated, standard reference samples were used and a set of specific operational criteria devised for successful application in this field. The reference standard crucially included and centred on was the National Institute of Standards and Technology (NIST) 'standard bullet'. This was to ensure that evaluation represented the practical examination of ballistic samples i.e. fired cartridge cases and bullets. It is concluded that focus-variation microscopy has potentially the most promising approach for a forensic laboratory instrument, in terms of functionality and 3D imaging performance, and is worthy of further investigation

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

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

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

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

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