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Controlling intercalations of PBDTTT-EFT side chain to initiate suitable network for charge extraction in PBDTTT-EFT:PC71BM blended bulk heterojunction solar cell
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Electrical, optical and structural properties, based on blend of PBDTTT-EFT:PC71BM bulk heterojunction solar cell is investigated. We have shown the presence of PC71BM in the blend facilitates interfaces for charge transfer mechanisms leading to PCEs of ~ 9.38%. GIXRD line profile obtained reveals that quantitative presence of PC71BM initiates a change in preferred orientation. It is proposed that PC71BM facilitates polymer alkyl side chain intercalations causing reduced d100 spacing, leading to larger π-π stacking of the back bone. The data obtained from d200 plane associated with PC71BM, reveals correlation between increased vertical stacking and PC71BM loading, suggesting a bicontinuous network for electron transport. Raman spectroscopy results provides evidence of PC71BM impact on frequency shift associated with C = C stretching mode of side chain thiophene rings responsible for of π-π spacing. Correlations between AFM surface roughness and blend ratio reveals migration of PC71BM to the film surface.
Keywords: (copolymer solar cell, power conversion efficiency, side chain intercalations, XRD
China:US intercountry adoption: a Quantitative Grounded Theory Study
Get PDFThis study sought to identify the factors influencing the scale and nature of intercountry adoption (ICA) between the People’s Republic of China and the United States of America; and to describe the significance and contribution of each to ICA processes.
It took a documentary data analysis approach based upon Quantitative Grounded Theory; firstly interpreting available data and thematically analyzing the literature in order to identify correlations between changes in the data and the environment for ICA.
The results showed that changes in policies, ethical narratives and ideological shifts (principally the rise of nationalism) appeared to influence both the scale and type of ICAs in successive years.
This paper concluded that China:US ICA is likely to continue only in small numbers with older and special needs children. However, China:US adoptions provide some examples of ‘best practice’. Understanding the interplay of factors explored theoretically in this study may guide future ICA arrangements between other country-pairs.
Originality/value
Although a range of data have been collected on China:US ICA over a number of years, no systematic attempt has been made to link changes in those data to changes in the legal, social or cultural climate in which such adoptions take place. As well as providing new insights into the dynamics of ICA, the paper develops an original method which could be applied to parallel arrangements between other countries
Development of the natural environment scoring tool (NEST)
Get PDFNatural environments (green and blue space) are associated with a range of health benefits, but their use is likely to be influenced by the presence of features, facilities and amenities and the condition/maintenance, or the natural environment quality. Most 'quality' assessment tools have focused on green spaces and their support for physical activity. This limits their utility for assessment of other natural environment typologies and uses (e.g., social, relaxation). We aimed to develop a tool for feasible, in situ assessment of diverse natural environments that might support a variety of uses, and to explore associations between natural environment quality and objectively measured amount of natural environment and neighbourhood-level socio-economic status (SES). This work was conducted as part of the PHENOTYPE project. Data were collected in 124 neighbourhoods in four European cities (Barcelona, Doetinchem, Kaunas, Stoke-on-Trent). The Natural Environment Scoring Tool (NEST) was developed using existing tools, expert input and field-testing. The final tool comprised 47-items across eight domains: Accessibility, Recreation facilities, Amenities, Aesthetics- natural, Aesthetics- non-natural, Significant natural features, Incivilities and Usability; typology-specific Overall Scores were derived. In total, 174 natural environments, covering a range of typologies, were audited. Mean time to complete NEST was 16±28 min. There was good inter-rater agreement. Mean domain scores showed some expected patterns by typology (e.g., higher Recreation Facilities scores in urban parks and formal recreation areas; lower Amenities scores in natural/semi-natural areas). Highest mean Overall Scores were observed for areas of blue space and woodland, the types of area that often lack the recreational facilities or amenities that can be dominant in physical activity-focused audit tools. There was a trend towards lower natural environment quality in neighbourhoods of lower SES, with some inter-city variation. Correlations between NEST scores and amount of natural environment indicated higher natural environment in areas with worse access. We recommend further testing of NEST in other locations in relation to use and health outcomes
Anomaly Detection Using Hierarchical Temporal Memory in Smart Homes
Get PDFThis work focuses on unsupervised biologically-inspired machine learning techniques and algorithms that can detect anomalies. Specifically, the aim is to investigate the applicability of the Hierarchical Temporal Memory (HTM) theory in detecting anomalies in the smart home domain. The HTM theory proposes a model for the neurons that is more faithful to the actual neurons than their usual counterparts in Artificial Neural Networks (ANN) based on the current Neuroscience understanding. The HTM theory has several algorithmic implementations, the most prominent one is the Cortical Learning Algorithm (CLA). The CLA model typically consists of three main regions: the encoder,
the spatial pooler and the temporal memory. Studying the performance of the CLA in the smart home domain revealed an issue with the standard encoders and high-dimensional datasets. In this domain, it is typical to have high-dimensional feature space representing the collection of smart devices. The standard CLA encoders are more suitable for low-dimensional datasets and there are encoders for categorical and scalar data types.
A novel Hash Indexed Sparse Distributed Representation (HI-SDR) encoder was proposed and developed, to overcome the high-dimensionality issue. The HI-SDR encoder creates unique representation of the data which allows the rest of the CLA regions to learn from. The standard approach when creating HTM models to work with datasets with many features is to concatenate the output of each encoder. This work concludes that the standard encoders produced representations for the input during every timestep that were similar and less distinguishable for the HTM model. This output similarity confuses the HTM model and makes it hard to discern meaningful representations. The
proposed novel encoder manages to capture the required properties in terms of sparsity and representations.
To investigate and validate the performance of a proposed machine learning technique, there has to be a representative dataset. In the smart home literature, there exists many real-world smart home datasets that allow the researchers to validate their models. However, most of the existing datasets are created for classification and recognition of Activities of Daily Living (ADL). The lack of datasets for anomaly detection applications in the domain of smart homes required the development of a simulation tool.
OpenSHS (Open Smart Home Simulator) was developed as an open-source, 3D and cross-platform smart home simulator that offers a novel hybrid approach to dataset generation.
The tool allows the researchers to design a smart home and populate it with
the needed smart devices. Then, the participants can use the designed smart home and simulate their habits and patterns.
Anomaly detection in the smart home domain is highly contextual and dependent on the inhabitant’s activities. One inhabitant’s anomaly could be the norm for another, therefore the definition of anomalies is a complex consideration. Using OpenSHS, seven participants were invited to generated forty-two datasets of their activities. Moreover, each participant defined his/her own anomalous pattern that he/she would like the model to detect. Thus, the resulting datasets are annotated with contextual anomalies specific to each participant.
The proposed encoder has been evaluated and compared against the standard CLA encoders and several state-of-the-art unsupervised anomaly detection algorithms, using Numenta Anomaly Benchmark (NAB). The HI-SDR encoder scored 81.9% accuracy, on the forty-two datasets, with 17.8% increase in accuracy compared to the k-NN algorithm and 47.5% increase over the standard CLA encoders. Using the Principal Component Analysis (PCA) algorithm as a preprocessing step proved to be beneficial to some
of the tested algorithms. The k-NN algorithm scored 39.9% accuracy without PCA and scored 64.1% accuracy with PCA. Similarly, the Histogram Based Outlier Score (HBOS) algorithm scored 28.5% accuracy without PCA and 61.9% with PCA.
The HTM-based models empirically showed good potential and exceeded in performance several algorithms, even without the HI-SDR encoder. However, the HTM-based models still lack an optimisation algorithm for its parameters when performing anomaly
detection
LDL Decomposition-based Real-time FPGA Implementation of DOA Estimation
Get PDFAn FPGA implementation and real-time experimental verification of proposed direction of arrival (DOA) estimation algorithm employing LDL factorization are
presented in this paper. The proposed algorithm is implemented on a Xilinx FPGA using LabVIEW software and its real-time experimental verification is performed using National Instruments (NI) PXI platform. The proposed method has several advantages over well-known methods which are based on either eigenvalue decomposition (EVD) or singular value decomposition (SVD). It provides faster
execution since LDL factorization requires O(n3/6) number of operations whereas EVD requires O(n3). Results from Matlab simulations and real-time experiments demonstrate the effectiveness of the proposed method. Successful FPGA
compilation reports show low resource usage and faster computation time for LDL-based method compared with QRbased implementations. Performance comparison is done in terms of estimation accuracy, FPGA processing time and
resource utilization
Hidden dangers revealed by misdiagnosed diabetic neuropathy: A comparison of simple clinical tests for the screening of vibration perception threshold at primary care level
No full textAim
Diabetic peripheral neuropathy is an important complication and contributes to the morbidity of diabetes mellitus. Evidence indicates early detection of diabetic peripheral neuropathy results in fewer foot ulcers and amputations. The aim of this study was to compare different screening modalities in the detection of diabetic peripheral neuropathy in a primary care setting.
Method
A prospective non-experimental comparative multi-centre cross sectional study was conducted in various Primary Health Centres. One hundred participants living with Type 2 diabetes for at least 10 years were recruited using a convenience sampling method. The Vibratip, 128 Hz tuning fork and neurothesiometer were compared in the detection of vibration perception.
Results
This study showed different results of diabetic peripheral neuropathy screening tests, even in the same group of participants. This study has shown that the percentage of participants who did not perceive vibrations was highest when using the VibraTip (28.5%). This was followed by the neurothesiometer (21%) and the 128 Hz tuning fork (12%) (p < 0.001).
Conclusion
Correct diagnosis and treatment of neuropathy in patients with diabetes is crucial. This study demonstrates that some instruments are more sensitive to vibration perception than others. We recommend that different modalities should be used in patients with diabetes and when results do not concur, further neurological evaluation should be performed. This would significantly reduce the proportion of patients with diabetes who would be falsely identified as having no peripheral neuropathy and subsequently denied the benefit of beneficial and effective secondary risk factor control
African States: Themes Emerging from the Human Rights Council's Universal Periodic Review
Get PDFThis article examines the themes emerging from the engagement of African states with the Universal Periodic Review (UPR) mechanisms of the UN Human Rights Council. The underlying principles of universality, cooperation and dialogue that guide the review have given African states a renewed sense of engagement with the international human rights institution. Despite the universality of the process, regionalism and cultural relativism are important aspects in the engagement of African states with the UPR mechanism. This article considers the extent to which regionalism and cultural relativism may prevent UPR from acting as an effective mechanism for human rights enforcement. It examines the potential for UPR to complement other national, regional and international human rights mechanisms, and the danger of state ritualism. These have ramifications for the extent to which UPR can achieve its goal of improving the human rights situation on the ground in Africa
Bullying and negative appearance feedback among adolescents: Is it objective or misperceived weight that matters?
Get PDFThis study investigated (1) whether involvement in bullying as a bully, victim or bully-victim was associated with objectively measured overweight or underweight, or whether it was related to weight misperception (i.e., inaccurate perceptions), and (2) whether appearance-specific feedback mediated the relationship between bullying and weight misperception. In Stage 1, 2782 adolescents aged 11-16 years from British secondary schools were screened for peer bullying and victimisation. In Stage 2, 411 adolescents with weight and height data (objective n=319, self-report n=92) also self-reported on their weight perception and appearance-specific feedback. Neither bullying nor victimisation were related to objective underweight or overweight. Victims were at increased odds of overweight misperception, while bully-victims were at increased odds of underweight misperception. Additionally, there was an indirect effect of appearance feedback on overweight misperception in bully-victims. Both victims and bully-victims are at increased risk of weight misperception, posing further detrimental effects to their health and wellbeing
Using the Care Excellence Framework to benchmark and improve patient care
Get PDFQuality is complex and difficult to define, and institutions and organisations often have their own definitions, measurements and assurance processes. The Care Excellence Framework (CEF), developed and used at University Hospitals of North Midlands NHS Trust, is a unique, integrated framework of measurement, clinical observation, patient and staff interviews and benchmarking. It also has an internal accreditation system that provides assurance from ward to board based on the five Care Quality Commission (CQC) domains and reflects CQC standards. The CEF has been established in its existing form since autumn 2016 and has been used in all areas of the organisation. This article provides an overview of the development and use of the CEF in an acute care setting, demonstrates how the framework acts as an internal accreditation system, and shows how it can encourage staff to undertake effective change and transform care from ordinary to excellent. [Abstract copyright: © 2018 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.
The life and legacy of Philip Astley, father of the modern circus
Get PDFDr Carmel Thomason from Staffordshire University worked with Brampton Museum and a group of volunteers to research the life of Philip Astley and his family in Newcastle-under-Lyme and the role of Astley’s theatrical performances in shaping recreational life of the period. The research was been compiled by Dr Carmel Thomason at Staffordshire University into a Resource Pack for a general audience. A printed edition of the pack was distributed at an event on 28 Nov 2018. The pack is available online as a series of downloadable pdfs via the Philip Astley Project website. http://www.philipastley.org.uk/resources
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