14,762 research outputs found

    Increased lifetime of Organic Photovoltaics (OPVs) and the impact of degradation, efficiency and costs in the LCOE of Emerging PVs

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    Emerging photovoltaic (PV) technologies such as organic photovoltaics (OPVs) and perovskites (PVKs) have the potential to disrupt the PV market due to their ease of fabrication (compatible with cheap roll-to-roll processing) and installation, as well as their significant efficiency improvements in recent years. However, rapid degradation is still an issue present in many emerging PVs, which must be addressed to enable their commercialisation. This thesis shows an OPV lifetime enhancing technique by adding the insulating polymer PMMA to the active layer, and a novel model for quantifying the impact of degradation (alongside efficiency and cost) upon levelized cost of energy (LCOE) in real world emerging PV installations. The effect of PMMA morphology on the success of a ternary strategy was investigated, leading to device design guidelines. It was found that either increasing the weight percent (wt%) or molecular weight (MW) of PMMA resulted in an increase in the volume of PMMA-rich islands, which provided the OPV protection against water and oxygen ingress. It was also found that adding PMMA can be effective in enhancing the lifetime of different active material combinations, although not to the same extent, and that processing additives can have a negative impact in the devices lifetime. A novel model was developed taking into account realistic degradation profile sourced from a literature review of state-of-the-art OPV and PVK devices. It was found that optimal strategies to improve LCOE depend on the present characteristics of a device, and that panels with a good balance of efficiency and degradation were better than panels with higher efficiency but higher degradation as well. Further, it was found that low-cost locations were more favoured from reductions in the degradation rate and module cost, whilst high-cost locations were more benefited from improvements in initial efficiency, lower discount rates and reductions in install costs

    The crisis of cultural authority in museums : contesting human remains in the collections of Britain

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    Museums in Britain have displayed and researched human remains since the eighteenth century. However, in the last two decades human remains in collections have become subject to claims and controversies. Firstly, human remains associated with acquisition during the colonial period have become increasingly difficult to retain and have been transfered to culturally affiliated overseas indigenous groups. Secondly, a group of British Pagans have formed to make claims on ancient human remains in collections. Thirdly, human remains that are not requested by any community group, and of all ages, have become the focus of concerns expressed about their treatment by members of the profession. A discourse arguing for 'respect' has emerged, which argues that all human remains should be treated with new care. The claims made on human remains have been vigourously but differentially contested by members of the sector, who consider the human remains to be unique research objects. This thesis charts the influences at play on the contestation over human remains and examines its construction. The academic literature tends to understand changes to museums as a result of external factors. This thesis argues that this problem is influenced by a crisis of legitimacy and establishes that there are strong internal influences. Through a weak social constructionist approach I demonstrate that the issue has been promoted by influential members of the sector as part of a broader attempt to distance themselves from their foundational role, as a consequence of a crisis of cultural authority stimulated by external and internal factors. The symbolic character of human remains in locating this problem is informed by the unique properties of dead bodies and is influenced by the significance of the body as a scientific object; its association with identity work and as a site of political struggle, in the high modem period

    Women’s Experiences of Accessing Breastfeeding and Perinatal Health Support in the Context of Intimate Partner Violence: An Interpretive Description Study

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    Background: Women experiencing intimate partner violence are at a heightened risk of negative perinatal and breastfeeding outcomes. This study explored the experiences of accessing breastfeeding support for women who endorse a history of intimate partner violence. A study of five in-depth semi-structured interviews were completed at 12-weeks postpartum with breastfeeding mothers with a history of intimate partner violence. Findings: Women expressed difficulties in accessing a healthcare provider who had specialized skill in breastfeeding support. Trust in their healthcare provider, built through displays of compassion and competence, was important to mitigate obstacles experienced during care access for this population. Trauma-and-violence-informed care principles were beneficial to the development of the therapeutic relationship in perinatal care. Women placed value on breastfeeding support received from both healthcare providers and social supports, which impacted mothers’ perceived breastfeeding support and self-efficacy. Further, mothers described increased levels of breastfeeding self-efficacy after engaging in a trauma-and-violence-informed care program aimed at supporting breastfeeding. Conclusions: Trauma-informed care may aid in the development of trust in the therapeutic relationship, which in turn impacts access to breastfeeding support and breastfeeding self-efficacy. The inclusion of trauma-and-violence informed principles in perinatal care may be effective at mitigating barriers to access for women who endorse a history of intimate partner violence. health care on how to employ trauma-informed breastfeeding care to may lead to better support for this population

    Coverage measurements of NB-IoT technology

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    Abstract. The narrowband internet of things (NB-IoT) is a cellular radio access technology that provides seamless connectivity to wireless IoT devices with low latency, low power consumption, and long-range coverage. For long-range coverage, NB-IoT offers a coverage enhancement (CE) mechanism that is achieved by repeating the transmission of signals. Good network coverage is essential to reduce the battery usage and power consumption of IoT devices, while poor network coverage increases the number of repetitions in transmission, which causes high power consumption of IoT devices. The primary objective of this work is to determine the network coverage of NB-IoT technology under the University of Oulu’s 5G test network (5GTN) base station. In this thesis work, measurement results on key performance indicators such as reference signal received power (RSRP), reference signal received quality (RSRQ), received signal strength indicator (RSSI), and signal to noise plus interference (SINR) have been reported. The goal of the measurement is to find out the NB-IoT signal strength at different locations, which are served by the 5GTN cells configured with different parameters, e.g., Tx power levels, antenna tilt angles. The signal strength of NB-IoT technology has been measured at different places under the 5GTN base station in Oulu, Finland. Drive tests have been conducted to measure the signal strength of NB-IoT technology by using the Quectel BG96 module, Qualcomm kDC-5737 dongle and Keysight Nemo Outdoor software. The results have shown the values of RSRP, RSRQ, RSSI, and SINR at different locations within several kilometres of the 5GTN base stations. These values indicate the performance of the network and are used to assess the performance of network services to the end-users. In this work, the overall performance of the network has been checked to verify if network performance meets good signal levels and good network coverage. Relevant details of the NB-IoT technology, the theory behind the signal coverage and comparisons with the measurement results have also been discussed to check the relevance of the measurement results

    In her own words: exploring the subjectivity of Freud’s ‘teacher’ Anna von Lieben

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    This project is inspired by Roy Porter (1985), who draws attention to the patient-shaped gap in medical history, and Rita Charon (2006), who emphasises the need to bring the patient’s narrative to the fore in the practice of medicine. The principal aim was to devise a means of accessing the lived experience of a patient who is no longer alive in order to gain an understanding of her narrative. Anna von Lieben was identified as a suitable subject as she wrote a substantial quantity of autopathographical poetry suitable for analysis and her status as Freud’s patient makes her a person of significant interest to the history of medicine. The poems were analysed using Interpretative Phenomenological Analysis (IPA), an idiographic and inductive method of qualitative research, based on Heideggerian hermeneutic phenomenology, which explores the lived experience of individuals and is committed to understanding the first-person perspective from the third-person position. The main findings from the IPA study reveal that Anna experienced a prolonged period of malaise, starting in late adolescence which she believed to result, at least partly, from a traumatic experience which occurred at that time. The analysis also indicates that Anna suffered from deep and lasting feelings of guilt and shame. The discovery of additional family documentation enabled me to contextualise and add substance to the findings of the IPA study. Anna’s husband’s diaries in particular reveal that Anna: • had a severe and longstanding gynaecological disorder • suffered from severe morphinism • did not benefit from Freud’s treatment which seemed neither to ease her symptoms nor identify any cause • was treated in Paris, not by Jean-Martin Charcot as previously supposed, but by a French hydrotherapist, Theodore Keller, who appears to have become a person of considerable significance in her life. The above findings led me to investigate Anna’s comorbidities (gynaecological disease and morphinism) and to show how those could be responsible for much of the symptomatology identified by Freud as ‘hysteria’. I then explore the possibility that her psychotic-like experiences could have been iatrogenically induced by her treatment first by Keller and then by Freud. Finally, I propose a fourfold set of hypotheses as an alternative to Freud’s diagnosis of hysteria

    BECOMEBECOME - A TRANSDISCIPLINARY METHODOLOGY BASED ON INFORMATION ABOUT THE OBSERVER

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    ABSTRACT Andrea T. R. Traldi BECOMEBECOME A Transdisciplinary Methodology Based on Information about the Observer The present research dissertation has been developed with the intention to provide practical strategies and discover new intellectual operations which can be used to generate Transdisciplinary insight. For this reason, this thesis creates access to new knowledge at different scales. Firstly, as it pertains to the scale of new knowledge generated by those who attend Becomebecome events. The open-source nature of the Becomebecome methodology makes it possible for participants in Becomebecome workshops, training programmes and residencies to generate new insight about the specific project they are working on, which then reinforce and expand the foundational principles of the theoretical background. Secondly, as it pertains to the scale of the Becomebecome framework, which remains independent of location and moment in time. The method proposed to access Transdisciplinary knowledge constitutes new knowledge in itself because the sequence of activities, described as physical and mental procedures and listed as essential criteria, have never been found organised 6 in such a specific order before. It is indeed the order in time, i.e. the sequence of the ideas and activities proposed, which allows one to transform Disciplinary knowledge via a new Transdisciplinary frame of reference. Lastly, new knowledge about Transdisciplinarity as a field of study is created as a consequence of the heretofore listed two processes. The first part of the thesis is designated ‘Becomebecome Theory’ and focuses on the theoretical background and the intellectual operations necessary to support the creation of new Transdisciplinary knowledge. The second part of the thesis is designated ‘Becomebecome Practice’ and provides practical examples of the application of such operations. Crucially, the theoretical model described as the foundation for the Becomebecome methodology (Becomebecome Theory) is process-based and constantly checked against the insight generated through Becomebecome Practice. To this effect, ‘information about the observer’ is proposed as a key notion which binds together Transdisciplinary resources from several studies in the hard sciences and humanities. It is a concept that enables understanding about why and how information that is generated through Becomebecome Practice is considered of paramount importance for establishing the reference parameters necessary to access Transdisciplinary insight which is meaningful to a specific project, a specific person, or a specific moment in time

    Balancing the urban stomach: public health, food selling and consumption in London, c. 1558-1640

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    Until recently, public health histories have been predominantly shaped by medical and scientific perspectives, to the neglect of their wider social, economic and political contexts. These medically-minded studies have tended to present broad, sweeping narratives of health policy's explicit successes or failures, often focusing on extraordinary periods of epidemic disease viewed from a national context. This approach is problematic, particularly in studies of public health practice prior to 1800. Before the rise of modern scientific medicine, public health policies were more often influenced by shared social, cultural, economic and religious values which favoured maintaining hierarchy, stability and concern for 'the common good'. These values have frequently been overlooked by modern researchers. This has yielded pessimistic assessments of contemporary sanitation, implying that local authorities did not care about or prioritise the health of populations. Overly medicalised perspectives have further restricted historians' investigation and use of source material, their interpretation of multifaceted and sometimes contested cultural practices such as fasting, and their examination of habitual - and not just extraordinary - health actions. These perspectives have encouraged a focus on reactive - rather than preventative - measures. This thesis contributes to a growing body of research that expands our restrictive understandings of pre-modern public health. It focuses on how public health practices were regulated, monitored and expanded in later Tudor and early Stuart London, with a particular focus on consumption and food-selling. Acknowledging the fundamental public health value of maintaining urban foodways, it investigates how contemporaries sought to manage consumption, food production waste, and vending practices in the early modern City's wards and parishes. It delineates the practical and political distinctions between food and medicine, broadly investigates the activities, reputations of and correlations between London's guild and itinerant food vendors and licensed and irregular medical practitioners, traces the directions in which different kinds of public health policy filtered up or down, and explores how policies were enacted at a national and local level. Finally, it compares and contrasts habitual and extraordinary public health regulations, with a particular focus on how perceptions of and actual food shortages, paired with the omnipresent threat of disease, impacted broader aspects of civic life

    Self-help/mutual aid groups in mental health : ideology, helping mechanisms and empowerment

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    In the last quarter of the twentieth century, self-help/mutual aid groups for mental health issues started to emerge in growing numbers, mainly in Western societies, offering and/or advocating for alternative non-traditional forms of support, and attracted the attention of many researchers and clinicians for their unique characteristics. Among the subjects of interest are typologies of groups, helping mechanisms and benefits from participation. However, there is lack of systematic research in the area and existing studies have been largely confined to the therapeutic value of these groups instead of acknowledging their socio-political meaning and subsequent psychosocial benefits for their members like personal empowerment. The present study was conducted during the transitional years from a Conservative to a newly elected Labour Government (1996 -1998), with subsequent policy shifts taking place in the welfare sector. The purpose of the study was to explore the potential of self-help groups as part of a broader new social movement, the service user movement, focussing on the English scene. It addressed this issue examining the relevance of a group typology based on political ideology and focus of change. To test the validity of this classification for members, a set of individual characteristics and group mechanisms as well as their change through time were examined. The sample consisted of fourteen mental health selfhelp/mutual aid groups from London and South East England, with a variety of structural and organisational features. The methodology used was a combination of both quantitative (self-completion questionnaires) and qualitative techniques (analysis of written material, participant observation and interviews). Measurements were repeated after a one-year interval (Time 1N=67, Time 2 N=56). Findings showed that, indeed, political ideology of self-help/mutual aid groups provided the basis of a meaningful typology and constitutes a comprehensive way of categorising them. Group ideology was related to specific helping mechanisms and aspects of personal empowerment. Specifically, conservative and combined group members reported more expressive group processes like sharing of feelings and self-disclosure, while radical group members were more empowered and optimistic. Group identification was also associated with specific helping activities and aspects of empowerment in the three group categories. The psychosocial character of group types and the beneficial outcomes for members remained stable through time. In general, prolonged participation was reflected in greater member identification with the group and resulted in improved mental wellbeing, increased social support, companionship and optimism for the future
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