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CSSR: a 2For1 Compressive Sensing Software Receiver with Combined Correlation For GPS-CA and Galileo-OS Signals
No full textThis is a 2for1 receiver because it acquires both GPS and Galileo signals at less than 50% of the complexity and processing time required by a Matched Filter acquisition receiver. CSSR is a new implementation of a dual-GNSS-signal Software Receiver using, for the first time, the compressive sensing technique to process the two GNSS signals at the same time (in this implementation, GPS C/A code and Galileo OS code signals are used). This paper describes this CSSR implementation, focusing on: (a) how we remove the subcarrier frequency effect from the Galileo signal, and combine it with the GPS signal as a BPSK like signal; (b) the pre-processing stage of the resultant BPSK signal to generate the non-Doppler shift vectors that compensates for the matching measurements in the compressive sensing process; and finally (c) the compressive sensing process to acquire both signals simultaneously by combining their dictionaries, or correlators. CSSR has been simulated using various actual signal conditions/scenarios. The results are compared to those obtained from running the same tests on 3-other matched filter receivers. CSSR achieves similar probability of detection to the others, and has a higher frequency resolution of 10Hz for the same 4ms dwell time.
With Application processors on-board Smartphones getting more powerful and cheaper, and with 60% of the 3.1 billion dual GNSS offering on-board current Smartphones are based on side-by-side implementations, we believe that CSSR is a good candidate to saving cost and valuable battery energy when implemented on-board Smartphones
The strangulation of female partners
No full textIn England and Wales, strangulation is one of the principal methods men use to kill women in intimate relationships. Over the past three decades, this method of killing accounts for up to 37 per cent of deaths of women by male partners.
Strangulation is both gender and context specific making it a high risk factor affecting the lives of women. The lack of understanding of the seriousness of strangulation, together with the legal construction of intention allows men to disavow murder and be found guilty of only unlawful act manslaughter. In most American and Australian Federal States and in Canada and New Zealand, legislation criminalises strangulation and is also an aggravating factor in sentencing in both non-fatal and fatal cases. This article makes a plea for law reform in England and Wales and a challenge to the prevailing discourse in criminal law and justice which continues to treat male body force in strangulation as less heinous than other forms of body force and weapons in fatal and non-fatal assaults against women
Lean Implementation within SMEs: a literature review
No full textPurpose – Lean business ideology has been one of the recent dominant research areas in operations management. However, there is a dearth of research focusing on Lean in small- and medium-sized enterprises (SMEs). The purpose of this paper is to fill this gap by systematically reviewing the literature in relation to the implementation of Lean in SMEs.
Design/methodology/approach – Tranfield et al.’s (2003) systematic review methodology was employed covering three stages: planning, conducting and reporting/dissemination.
Findings – A descriptive analysis of the papers reviewed is provided. From the thematic analysis of the literature four main themes are identified: the scope/type of Lean being adopted by SMEs, how Lean is used in SMEs, the impact of Lean implementation on SMEs and the critical success factors for Lean implementation in SMEs. Key inhibitors and enablers related to firm size when implementing Lean are also identified in the concluding discussion.
Research limitations/implications – Nine recommendations for future research are developed associated with Lean implementation in SMEs.
Practical implications – The authors suggest SMEs to integrate organisational factors such as employee empowerment and the development of a supportive strategy into their Lean implementation plans. A preliminary “Staircase Road Map” to guide SMEs in implementing Lean is also developed.
Originality/value – This paper goes beyond previous literature reviews of Lean by systematically and critically evaluating key themes of Lean implementation within an SME environment. It not only provides a road map for SME owners/managers who intend to implement Lean, but also provides the academic community with an agenda for future research
In defence of democracy: the criminalisation of impersonation
No full textThis article offers a philosophical justification for the criminalisation of voting as another person (impersonation or, in English law, personation) in public elections by arguing that it involves wrongdoing in the form of anti-democratic behaviour and that the failure to criminalise it will harm the public good of electoral integrity. With regard to harm, the article argues that the failure to criminalise impersonation will eventually result in widespread impersonation, such widespread impersonation undermining electoral integrity, itself instrumental to a number of public goods reflecting the democratic character of any given polity. Finally, the article completes the case for criminalisation by arguing that, in any given jurisdiction, it may be neither effective nor desirable for the entire burden of preventing impersonation to fall onto the civil law, with the result that the criminalisation of impersonation can serve a useful complementary role to the civil law in maintaining electoral integrity
Lipopolysaccharide induces a downregulation of adiponectin receptors in-vitro and in-vivo
Get PDFBackground. Adipose tissue contributes to the inflammatory response through production of cytokines, recruitment of macrophages and modulation of the adiponectin system. Previous studies have identified a down-regulation of
adiponectin in pathologies characterised by acute (sepsis and endotoxaemia) and chronic inflammation (obesity and type-II diabetes mellitus). In this study, we investigated
the hypothesis that LPS would reduce adiponectin receptor expression in a murine model of endotoxaemia and in adipoocyte andmyocyte cell cultures.
Methods. 25 mg/kg LPS was injected intra-peritoneally into C57BL/6J mice,equivalent volumes of normal saline were used in control animals. Mice were killed at 4 or 24 h post injection and tissues harvested. Murine adipocytes
(3T3-L1) and myocytes (C2C12) were grown in standard culture, treated with LPS (0.1 μg/ml–10 μg/ml) and harvested at 4 and 24 h. RNA was extracted and qPCR was conducted according to standard protocols and relative expression was calculated.
Results. After LPS treatment there was a significant reduction after 4 h in gene expression of adipo R1 in muscle and peri-renal fat and of adipo R2 in liver, peri-renal fat and abdominal wall subcutaneous fat. After 24 h, significant reductions were limited tomuscle. Cell culture extracts showed varied changes with reduction in adiponectin and adipo R2 gene expression only in adipocytes.
Conclusions. LPS reduced adiponectin receptor gene expression in several tissues including adipocytes. This reflects a down-regulation of this anti-inflammatory and
insulin-sensitising pathway in response to LPS. The trend towards base line after 24 h in tissue depots may reflect counter-regulatory mechanisms. Adiponectin receptor
regulation differs in the tissues investigated
UNILS: Unconstrained indoors localization scheme based on Cooperative Smartphones networking with onboard inertial, Bluetooth and GNSS devices
Get PDFLocation-based services (LBS) are becoming an important feature on today’s smartphones (SPs), tablets and wearable devices. Seamless outdoors-indoors navigation, and especially for accurate indoors localization, is the main demand of LBS users. Onboard WiFi, Bluetooth (BT) or inertial-sensors technologies have been proven to somewhat provide alternative solutions in GNSS-signal-denied areas (i.e. indoors) to define SPs location. However, limited coverage of WiFi access-points (WAPs), pre-installed BT-anchors, constrained of WAPs/BT-anchors physical positions within a building, and limitations of existing localisation techniques (in a standalone mode) on SPs are some of the main challenges to designing a spontaneous autonomous positioning solution with reliable accuracy at reasonable cost.
This paper proposes an unconstrained indoors localization scheme (UNILS) based on cooperative SPs networking to tackle these challenges. The aim of this new scheme is to fuse multi-technologies measurements on SPs.
The scheme uses relative-pseudoranging (based on time-of-arrival TOA technique) approach between the connected SPs that are GNSS enabled, especially when the majority of the SPs are outdoors, and combining this with uncertainty calculations from onboard dead-reckoning (DR) measurements using Kalman Filter, that can provide seamless and improve location accuracy significantly, especially when deep indoors. This means that, in deep indoors, UNILS can utilize only available devices/sensors on SPs, when communication with WAPs or BT-anchors is deemed unreliable or unavailable, to offer reasonable cost & good localization performance.
Results obtained from actual trials & simulations (using OPNET) of this scheme (based on Android-SPs network implementations for various indoors scenarios) show that around 3-meters accuracy can be achieved when locating SPs at various deep indoors situations
Biometrics Writer Recognition for Arabic language: Analysis and Classification techniques using Subwords Features
No full textHandwritten text in any language is believed to convey a great deal of information about writers’ personality and identity. Indeed, handwritten signature has long been accepted as an authentication of the writer’s physical stamp on financial and legal deals as well official/personal documents and works of art. Handwritten documents are frequently used as evidences in forensic tasks. Handwriting skills is learnt and developed from the early schooling stages. Research interest in behavioral biometrics was the main driving force behind the growth in research into Writer Identification (WI) from handwritten text, but recent rise in terrorism associated with extreme religious ideologies spreading primarily, but not exclusively, from the middle-east has led to a surge of interest in WI from handwritten text in Arabic and similar languages.
This thesis is the main outcome of extensive research investigations conducted with the aim of developing an automatic identification of a person from handwritten Arabic text samples. My motivations and interests, as an Iraqi researcher, emanate from my multi-faceted desires to provide scientific support for my people in their fight against terrorism by providing forensic evidences, and as contribute to the ongoing digitization of the Iraqi National archive as well as the wealth of religious and historical archives in Iraq and the middle-east. Good knowledge of the underlying language is invaluable in this project.
Despite the rising interest in this recognition modality worldwide, Arabic writer identification has not been addressed as extensively as Latin writer identification. However, in recent years some new Arabic writer identification approaches have been proposed some of which are reviewed in this thesis. Arabic is a cursive language when handwritten. This means that each and every writer in this language develops some unique features that could demonstrate writer’s habits and style. These habits and styles are considered as unique WI features and determining factors.
Existing dominating approaches to WI are based on recognizing handwriting habits/styles are embedded in certain parts/components of the written texts. Although the appearance of these components within long text contain rich information and clues to writer identity, the most common approaches to WI in Arabic in the literature are based on features extracted from paragraph(s), line(s), word(s), character(s), and/or a part of a character. Generally, Arabic words are made up of one or more subwords at the end of each; there is a connected stroke with a certain style of which seem to be most representative of writers habits. Another feature of Arabic writing is to do with diacritics that are added to written words/subwords, to add meaning and pronunciation. Subwords are more frequent in written Arabic text and appear as part of several different words or as full individual words. Thus, we propose a new innovative approach based on a seemingly plausible hypothesis that subwords based WI yields significant increase in accuracy over existing approaches. The thesis most significant contributions can be summarized as follows:
- Developed a high performing segmentation of scanned text images, that combines threshold based binarisation, morphological operation and active shape model.
- Defined digital measures and formed a 15-dimensional feature vectors representations of subwords that implicitly cover its diacritics and strokes. A pilot study that incrementally added features according to writer discriminating power. This reduced subwords feature vector dimension to 8, two of which were modelled as time series.
- For the dependent 8-dimensional WI scheme, we identify the best performing set of subwords (best 22 subwords out of 49 then followed by best 11 out of these 22 subwords).
- We established the validity of our hypothesis for different versions of subwords based WI schemes by providing empirical evidence when testing on a number of existing text dependent and in text-dependent databases plus a simulated text-in text-dependent DB. The text-dependent scenario results exhibited possible present of the Doddington Zoo phenomena.
- The final optimal subword based WI scheme, not only removes the need to include diacritics as part of the subword but also demonstrating that including diacritics within subwords impairs the WI discriminating power of subwords. This should not be taken to discredit research that are based on diacritics based WI. Also in this subword body (without diacritics) base WI scheme, resulted in eliminating the presence of Doddington Zoo effect.
- Finally, a significant but un-intended consequence of using subwords for WI is that there is no difference between a text-independent scenario and text-dependent one. In fact, we shall demonstrate that the text-dependent database of the 27-words can be used to simulate the testing of the scheme for an in text-dependent database without the need to record such a DB.
Finally, we discussed ways of optimising the performance of our last scheme by considering possible ways of complementing our scheme using the addition of various image texture analysis features to be extracted from subwords, lines, paragraphs or entire file of the scabbed image. These included LBP and Gabor Filter. We also suggested the possible addition of few more features
Multi-GNSS signals acquisition techniques for software defines receivers
No full textAny commercially viable wireless solution onboard Smartphones should resolve the technical issues as well as preserving the limited resources available such as processing and battery. Therefore, integrating/combining the process of more than one function will free up much needed resources that can be then reused to enhance these functions further. This thesis details my innovative solutions that integrate multi-GNSS signals of specific civilian transmission from GPS, Galileo and GLONASS systems, and process them in a single RF front-end channel (detection and acquisition), ideal for GNSS software receiver onboard Smartphones.
During the course of my PhD study, the focus of my work was on improving the reception and processing of localisation techniques based on signals from multi-satellite systems. I have published seven papers on new acquisition solutions for single and multi-GNSS signals based on the bandpass sampling and the compressive sensing techniques. These solutions, when applied onboard Smartphones, shall not only enhance the performance of the GNSS localisation solution but also reduce the implementation complexity (size and processing requirements) and thus save valuable processing time and battery energy.
Firstly, my research has exploited the bandpass sampling technique, if being a good candidate for processing multi-signals at the same time. This portion of the work has produced three methods. The first method is designed to detect the GPS, Galileo and GLONASS-CDMA signals’ presence at an early stage before the acquisition process. This is to avoid wasting processing resources that are normally spent on chasing signals not present/non-existent. The second focuses on overcoming the ambiguity when acquiring Galileo-OS signal at a code phase resolution equal to 0.5 Chip or higher and this achieved by multiplying the received signal with the generated sub-carrier frequency. This new conversion saves doing a complete correlation chain processing when compared to conventionally used methods. The third method simplifies the joining implementation of the Galileo-OS data-pilot signal acquisition by constructing an orthogonal signal so as to acquire them in a single correlation chain, yet offering the same performance as using two correlation chains.
Secondly, the compressive sensing technique is used to acquire multi-GNSS signals to achieve computation complexity reduction over correlator based methods, like Matched Filter, while still maintaining acquisition integrity. As a result of this research work, four implementation methods were produced to handle single or multi-GNSS signals. The first of these methods is designed to change dynamically the number and the size of the required channels/correlators according to the received GPS signal-power during the acquisition process. This adaptive solution offers better fix capability when the GPS receiver is located in a harsh signal environment, or it will save valuable processing/decoding time when the receiver is outdoors. The second method enhances the sensing process of the compressive sensing framework by using a deterministic orthogonal waveform such as the Hadamard matrix, which enabled us to sample the signal at the information band and reconstruct it without information loss. This experience in compressive sensing led the research to manage more reduction in terms of computational complexity and memory requirements in the third method that decomposes the dictionary matrix (representing a bank of correlators), saving more than 80% in signal acquisition process without loss of the integration between the code and frequency, irrespective of the signal strength. The decomposition is realised by removing the generated Doppler shifts from the dictionary matrix, while keeping the carrier frequency fixed for all these generated shifted satellites codes. This novelty of the decomposed dictionary implementation enabled other GNSS signals to be combined with the GPS signal without large overhead if the two, or more, signals are folded or down-converted to the same intermediate frequency. The fourth method is, therefore, implemented for the first time, a novel compressive sensing software receiver that acquires both GPS and Galileo signals simultaneously. The performance of this method is as good as that of a Matched Filter implementation performance. However, this implementation achieves a saving of 50% in processing time and produces a fine frequency for the Doppler shift at resolution within 10Hz.
Our experimental results, based on actual RF captured signals and other simulation environments, have proven that all above seven implementation methods produced by this thesis retain much valuable battery energy and processing resources onboard Smartphones
Worthy of better Memory: The Royal Navy and the defence of the Eastern Empire 1935 - 1942
Get PDFThis thesis proposes major revisions to the history of the naval defence of Britain’s
Eastern Empire during the critical period 1935 – 42 as the Royal Navy (RN) sought to
manage the increasing risks posed by three potential Axis enemies across divergent
theatres. It challenges the prevailing historical interpretation which explains the
successive defeats suffered by the RN at the start of the war with Japan as the inevitable
consequence of resource weakness and imperial overstretch already evident in a deeply
flawed pre-war strategy “Main Fleet to Singapore”. The dominant narrative argues that:
Britain never had the naval resources to protect a two hemisphere Empire let alone cope
with a triple threat from Germany, Italy and Japan; it certainly could not pose any
effective counterweight to Japan once it was fighting for its life in Europe; and it
compounded resource weakness by consistently underestimating the Imperial Japanese
Navy (IJN) and failing to recognise the potential of modern airpower at sea. Britain’s
strategy for defending its Eastern Empire through naval power therefore rested on
convenient self-deception regarding Japanese intent and the balance of relative capability
whereas in reality the RN was decisively outmatched. Furthermore, most historians
suggest that, while Britain’s initial war with Japan ended in ignominy, this had little
impact on the overall global struggle against the Axis because Britain’s role in the East
was essentially irrelevant to the Allied cause whatever the losses to its own imperial
standing.
This thesis contends that the dominant narrative is neither satisfactory nor sufficient and
reflects important gaps in the historical record. But it also argues that the historiography
of the last 50 years has defined the RN role in protecting the Eastern Empire in very
narrow terms, focusing almost exclusively on the defence of the Far East territories and
the prospects of deploying a fleet to Singapore. In reality, the Eastern Empire
encompassed a much wider area and it faced existential threats on its western boundary as
well as in the east. Ensuring the security of this wider area had profound implications not
just for Britain’s own war-making potential but for the overall Allied cause too. The
thesis therefore offers an interpretation which, for the first time, investigates thoroughly
the inter-dependencies between different theatres of war hitherto viewed principally in
their own terms. By taking this wider perspective, it demonstrates that not only was there
more coherence and continuity to RN policy and strategy towards the Eastern Empire in
this period than historians have traditionally accepted but that it also reflected greater
realism about what truly mattered and where naval resources should best be concentrated
at any given time. In doing so, it shows how and why prevailing accounts are defective.
The thesis proposes five main arguments across the period 1935 – 1942. First, it shows
that the RN of 1939 was stronger, more capable, more innovative, and more ambitious in
its strategic goals than the mainstream accounts of its inter-war history have generally
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accepted. It is simply not the case that meeting the demands of a multi-theatre war over
the next three years as the output of the rearmament programme became available was out
of reach as many have argued. It then demonstrates that British strategy to ensure
adequate security through naval power for the core territories of the Eastern Empire in the
face of the Triple Threat was more flexible and realistic, and better directed at what would
prove to be the critical points in the first half of the war, than the prevailing historical
narrative recognises. Thirdly, by looking at all relevant theatres simultaneously, it argues
that Britain’s investment in the Middle East, and the RN commitment to the Eastern
Mediterranean, from 1940 – 42, were essential both to protect the Eastern Empire and its
resources and to enable it to generate maximum war potential. This commitment also
vitally influenced the security of the Atlantic lifeline. It was not a diversion but an
essential complement to meeting the threat from Japan.
The thesis then re-examines the disasters suffered by the RN in the first phase of the war
with Japan. It argues that promises of US naval support in the Atlantic and exaggerated
expectations of the deterrent power the US could exercise against Japan allowed Britain’s
war leadership to believe it could maintain a forward defence strategy in the Middle and
Far East theatres simultaneously. This goal was never realistic with the resources Britain
was able and willing to deploy overseas; yet it was the Admiralty, rather than the Prime
Minister, who showed a reckless disregard for the resulting risks in the immediate run-up
to war. In reality, the exercise of naval power to secure what mattered in the Eastern
Empire did not ultimately depend on holding Singapore.
The final line of argument is that it is simply not possible to reach a secure judgement on
the eastern theatre without a proper understanding of how it interacted with the other war
theatres and how this then influenced the decision-makers of the day. The thesis shows
how the entry of Japan into the war confirmed that the Indian Ocean was an inescapable
defence commitment, critical not just for Britain but also the wider Allied cause, ranking
indeed second only to the Atlantic lifeline in importance. Despite the defeats suffered in
the first months of the Far East war, the thesis demonstrates how the RN could still
generate sufficient power by mid-1942 to defend this theatre against any naval force Japan
was likely to deploy.
The 1935 start date for the thesis marks the point when the threats posed by a resurgent
Germany, an increasingly hostile Japan, and unpredictable Italy, moved from theoretical
to real. The end of 1942 is an appropriate finishing point because, as the thesis explains, it
marks the end of any credible threat from the Axis to the core Eastern Empire through
either the Indian Ocean or the Middle East
Bank Distress and Firms’ Investment during the Great Recession - Evidence from Ireland
Get PDFThis paper investigates the impact of bank distress on firms’ performance using unique data during the Great Recession for Ireland. The results show that bank distress, measured as banks’ credit default swap spreads (CDS), has negatively and statistically significantly affected firms’ investment expenditures. Interestingly, firms with access to alternative sources of external finance are not impacted by bank distress. The results are robust to accounting for external finance dependence, demand and trade sensitivities, which affect firm performance and the demand for credit