E-Jurnal Universitas Tunas Husada Tasikmalaya
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Probabilistic Shaping Based Spatial Modulation for Spectral-Efficient VLC
No full textVisible light communication (VLC) is a promising technology for 6th-generation (6G) networks because of its attractive feature such as a wide unlicensed spectrum. In this paper, a novel adaptive coded spatial modulation scheme with probabilistic shaping (PS) is proposed to approach the capacity of the spatial modulation (SM) in VLC channels with intensity modulation and direct detection (IM/DD). In the proposed scheme, spatial and constellation symbols are probabilistically shaped depending on the user's location inside the room and the optical signal-to-noise ratio (OSNR). Moreover, we optimize the channel coding rate to maximize further the achievable rate of the proposed scheme for a given OSNR. Finally, we propose an algorithm to compute the capacity-achieving distribution of the proposed scheme with unipolar M-ary pulse amplitude modulation (PAM) signaling. The proposed scheme outperforms uniform and an orthogonal frequency-division multiplexing (OFDM) based scheme in terms of spectral efficiency (SE) and/or frame error rate (FER). For example, for 8-PAM signaling with N = 8 transmit antennas, the proposed scheme operates within 0.2 dB from the unipolar M-PAM SM VLC channel signaling capacity and outperforms the uniform and OFDM based schemes in terms of FER by at least 1.1 dB and 1.3 dB at a normalized data rate of 1.33 bits per channel use per sub-carrier (b/cu/sc), respectively
Combined Learning Models for AnalysingTimeseries Data in Healthcare
No full text"The developments in data collection technologies and their growing availability lead to an extensive amount of time-series data. The collected data contain information from people's day-to-day lives, health status or activities. However, this huge amount of data need to be analysed to extract useful information. These insights about human lives and health can be helpful in different fields and areas such as marketing, transportation, health tracking and improving quality of life, education and safety.There are extensive research and studies to improve the time-series analysis. One area which has gained more attention is machine learning and deep learning. Machine learning can be useful in gathering insight from massive datasets and developing models for predictive reasons. However, there are challenges in applying machine learning methods and techniques to time-series data.This research proposes a number of methods to tackle some of the challenges and issues in this area. This work proposes a novel representation model to deal with high-dimensionality of time-series data. The model preserves the principal information of data and we demonstrate how this data representation can be used in different time-series data analysis such as clustering, classification and change point detection. We also compared the proposed model with other representation models in clustering which showed 20% higher clustering quality in Silhouette coefficient measure.Healthcare and especially remote healthcare is an area that can benefit from time-series data analysis. An attention-based model has also been implemented in a dementia care project. Attention-based model is a deep learning model that can find important features in data and give higher weight to them in the prediction. The proposed model is able to detect the risk of adverse health related incidents at the homes of people with dementia with a recall of 91% and precision of 83%.Finally, to further improve robustness of the analysis methods, a semi-supervised model has been developed. The model can use a limited amount of labelled data and improve the performance compared to other state-of-the-art models. The model shows 27% higher recall in average compared with other models in detecting agitation in people with dementia.
Hazard considerations in the vulnerability assessment of offshore wind farms in seismic zones
No full textOffshore wind power is increasingly becoming a mainstream energysource, and efforts are underway toward their construction in seismiczones. An offshore wind farm consists of generation assets (turbines) andtransmission assets (substations and cables). Wind turbines are dynami-cally sensitive systems due to the proximity of their resonant frequency tothat of loads considered in their analyses. Such farms are consideredlifeline systems and need to remain operational even after largeearthquakes. This study aims to discuss hazard considerations involvedin the resilience assessment of offshore wind farms in seismic regions. Thecomplexity of design increases with larger turbines installed in deeperwaters, resulting in different types of foundations. In addition, Tsunamiinundation is shown to be an important consideration for nearshoreturbines
Reason, Respect, and the Law: Bernard Williams and Legal Normativity
No full textIn this thesis, I offer a novel account of how the law provides reasons for action that draws from the moral philosopher Bernard Williams. A first claim I make regards how concrete agents reason. I will put forward a view that takes into account the projects, values, attachments, and dispositions that agents have. This picture is a kind of “reasons internalism” that combines Williams’ original claims with Harry Frankfurt’s structure of care. Once we have that picture, I provide an account of motivations and dispositions that agents have, notably the notions of character, identity and respect. Alongside those discussions, I analyse a second claim. Drawing from Joseph Raz and John Deigh, I argue that, given law’s part in a narrative of political rule, it is a characteristic feature of law that it demands respect from its subjects; respect here meaning that the subjects at least see some good or value in the law that grounds at least reasons to not act against it. There are, then, considerations moving from two directions: from one side, we have law’s demand for respect moving from the law to the subjects; from the other, the contents of peoples’ “subjective motivational sets” that enable agents to make sense of law’s demand and abide by them when the requisite relationships between law and agents are present. For instance, an agent might identify herself with the law, or she might respect it but see it as something she does not identify herself with, or she might simply abide by the law because of prudential reasons or similar considerations. Those relationships account for much of law’s power to provide reasons for action. I hope to present a view on the reason-giving character of the law that takes seriously the phenomenology of action from a first-personal point of view
Radiative Capture on Nuclear Isomers: Direct Measurement of the ²⁶ᵐAl (p, γ) ²⁷Si Reaction
No full textWe present the first direct measurement of an astrophysical reaction using a radioactive beam of isomeric nuclei. In particular, we have measured the strength of the key 447-keV resonance in the ²⁶ᵐAl (p, γ) ²⁷Si reaction to be 432 +146-226 meV and find that this resonance dominates the thermally averaged reaction rate for temperatures between 0.3 and 2.5 GK. This work represents a critical development in resolving one of the longest standing issues in nuclear astrophysics research, relating to the measurement of proton capture reactions on excited quantum levels, and offers unique insight into the destruction of isomeric ²⁶Al in astrophysical plasmas
Vitamin D Status in Saudi Arabia: Metabolic and Genetic Association Study
No full textVitamin D (vitD) deficiency is a key public health issue worldwide. Despite the abundance of sunlight exposure in countries in the Middle East, including Saudi Arabia, vitD deficiency is still highly prevalent in these regions and particularly in postmenopausal women. VitD is mainly bound to vitD binding protein (VDBP), while the unbound form of vitD (˂1%) is said to be free. Free 25(OH)D is suggested to be more precise than total 25(OH)D in evaluating vitD status, especially in a population with different ethnic groups. Furthermore, the association between vitD and type 2 diabetes mellitus (T2DM), and the influence of genetic polymorphisms in genes involved in vitD metabolism on 25(OH)D levels seem to differ between the ethnic groups. Therefore, the aims of this PhD project were as follows: (i) Determine vitD status (total and free 25(OH)D) and its association with metabolic health parameters and specific single-nucleotide polymorphisms (SNP) in vitD related genes in a multi-ethnic vitD deficiency high risk cohort, particularly postmenopausal women in Saudi Arabia; (ii) Look for known or novel genetic variations in genes involved in vitD metabolism in families diagnosed with vitD deficiency in Saudi Arabia; (iii) Investigate the association between vitD and glycaemic parameters in a multi-ethnic cohort of postmenopausal women with T2DM in Saudi Arabia.Study (i) included a multi-ethnic cohort of 459 postmenopausal healthy women aged between 50 and 81 years, randomly recruited from seven primary health care centers scattered in Jeddah, Saudi Arabia. Blood samples were collected from subjects for measurement of serum levels of total 25(OH)D, directly measured free 25(OH)D, VDBP, metabolic bone parameters, lipid profile and other serum biochemical tests .Around 49% of the participants had optimal total 25(OH)D level (≥20 ng/ml) according to Institute of Medicine. Total 25(OH)D level was associated with rs7041 SNP in GC gene (P=0.023). A positive correlation was found between directly measured free and total 25(OH)D (r=0.61, P<0.0001). The total, but not free 25(OH)D showed significant association with serum intact parathyroid hormone (PTH), blood pressure, waist and hip circumferences (P<0.05); whilst free 25(OH)D but not total 25(OH)D showed a significant association with total cholesterol and LDL-C (P=0.027 and P=0.022; respectively). These observed total 25(OH)D significant associations were significantly affected by ethnic group.Study (ii) involved 21 families with vitD deficiency (n=39) in Saudi Arabia. WES was performed for DNA samples, then resulting WES data was filtered and a number of variants were prioritized and validated by Sanger DNA sequencing. We were able to find a novel mutation in DHCR7 (rs143587828) in two subjects from one family, and a polymorphism in LRP2 (rs2075252) in 3 families (2 subjects from each family, n=6). When these variants were validated, they were not observed in controls (n=100) which may suggest that these genetic variants might affect vitD levels and influence vitD status. Further studies are now required to confirm the association of these variants with vitD deficiency.Study (iii) involved a multi-ethnic cohort of postmenopausal females (n = 173, age ≥ 50 years) with T2DM. Several biochemical parameters were measured including total 25(OH)D, glycosylated hemoglobin, insulin, glucose, c-peptide and insulin sensitivity indices. VitD status was inversely associated with insulin resistance and anthropometric measures in this cohort [fasting glucose (r=-0.165, P=0.037), insulin (r=-0.184, P=0.02), C-peptide (r=-0.19, P=0.015), HOMA2- IR C-peptide (r=-0.23,P=0.004), body weight (r=-0.173 P=0.028), waist and hip circumferences (r=-0.167, P=0.033; r=-0.22, P=0.004 respectively)]. Our findings also showed that vitD associations with insulin resistance and anthropometric measures in women with white ethnicity were significant (P<0.05); unlike those from black/Asian ethnic backgrounds
Novel stress granules-like structures are induced via a paracrine mechanism during viral infection
No full textEssays on Monetary Policy
No full textThis thesis consists of two independent chapters on monetary policy.Chapter 1 studies optimal monetary policy under imperfect credibility in a New Keynesian model with staggered price and wage setting. In our imperfect credibility framework, the central bank commits to a policy plan but occasionally reneges on past promises with a given common knowledge probability. We find that the welfare gains from increasing credibility are approximately linear on the initial credibility level. The variance decomposition shows that wage markup shocks are the main driver of economic fluctuations and that these shocks are better contained when credibility is high. We then show that the degree of credibility impacts the effect of wage flexibility on welfare. When credibility is low, monetary policy is less potent and the economy can experience a feedback loop between wage volatility and price volatility. We show, though, that once wage markup shocks are considered, wage flexibility is welfare improving.Chapter 2 examines the effects of higher inflation expectations on households' consumption plans. Higher inflation expectations can boost private consumption if the real interest rate decreases. However, households often report that they dislike high inflation due to the erosion of nominal income, and standard models often abstract from this channel. This chapter uses a dataset with quantitative expectations for both inflation and nominal interest rates, which allow us to determine consumption behavior both during normal times and zero lower bound (ZLB) periods. We find that higher inflation expectations encourage households to bring forward durable goods purchases while discouraging spending on non-durables. We show that these results are consistent with a model in which higher inflation expectations erode a household's permanent income thereby discouraging non-durable consumption, whereas durable consumption increases due to the lower real rate. Moreover, we analyze different counterfactuals and show that nominal wage expectations are central
The economics of quality management in the Irish hotel industry
No full textGoal and objectives of the dissertationGoalTo explore the economics of quality management through a financial analysis of the resources that influence hotel performance.This treatise was stimulated by an exploration into the economics of quality management through a financial analysis of the resources, both inputs and outputs, that influence hotel performance. In doing so, this dissertation provided a pragmatic examination of quality management and performance measurement through an interdisciplinary of services marketing and management, tourism economics, and financial management. The goal and objectives of this dissertationare underpinned by three significant research gaps. The first gap in knowledge relates to the economics of hotel quality logic (Skalpe & Sandvik, 2002)and by examining the multifaceted relationship between quality management, productivity, and profitability in the hotel industry (Altin et al., 2018; Gummesson, 2014).The second research gap was motivated by the inconclusive debate around a systems approach to quality management in hospitality and by being able to measure the actual implementation and awareness of formalised quality management systems by the hotel trade(Farrington et al., 2018; Heras-Saizarbitoria et al., 2015). Finally, the third research gap was determined by the impact of quality management, in monetary terms, on hotel performance. This gap was influenced by how the elusiveness of service quality as a theoretical concept can present real challenges to the methods employed for determining the empirical monetary impact of quality management on hotel performance (Lai et al., 2018).Objectives1.To identify the key theoretical constructs for exploring the economics of quality management in the hotel industry.2.To investigate hotel managers’ perceptions and implementation of formalised quality management systems and practices.3.To explore the techniques of service productivity analysis and profit sensitivity analysis (PSA) as a systematic means in measuring the effect of quality management on a hotel’s net income.4.To develop a holistic model which conceptualises the economics of quality management in the hotel industry.MethodologyThis research employed a pragmatic perspective and adopted a sequential two-phase mixed methods research design (Creswell & Plano Clark, 2018). Research Phase 1 involved a survey methodology dominated by a quantitative data collection and analysis. An online self-administered questionnaire was employed in Phase 1 to examine hotel managers’ perceptions of formalised quality management systems (QMSs) and practices within the Irish hotel industry.Research Phase 2 consisted of a case study methodology to explore the techniques of service productivity analysis (Grönroos & Ojasalo, 2004)and profit sensitivity analysis (PSA) (Kotas & Wanhill, 1981)as a systematic means in measuring the effect of quality management on a hotel’s net income. An Irish four-star hotel formed the basis of the case study approach adopted in Research Phase 2. The chosen data collection methods in Phase 2 included archival records and a continuous unstructured interview (Saunders & Lewis, 2018). This study’s two-phase research design was embedded within the Preliminary Research Phase of the literature review and the concluding discussion of the thesis findings. The mixed methods research approach employed in this study, especially the chosen methods thatReardon(2022)/ European Journal of Tourism Research31, 31183formed part of the sequential two-phase research design, generated answers to the four objectives and also aided the development of a holistic understanding of the economics of quality management in the hotel industry.ResultsA key contribution of this study is the development and re-conceptualisation of the economics of quality logic (Skalpe & Sandvik, 2002), in the hotel industry. In so doing, this study’s findings depict the complex and often contradictory nature of how quality management is perceived by tourism and hospitality firms. The most significant findings of this study contribute to knowledge in four key areas. First, the findings identified the key theoretical constructs for exploring the economics of quality management in the hotel industry. Second, hotel managers’ perceptions and implementation of formalised QMSs and practices were investigated revealing negative connotations of a systems approach to quality management by the hotel trade. Third, the techniques utilised in the single-case analysis of Hotel X illustrated how to measure the impact of a hotel’s quality management efforts on net income. However, the findings also highlighted the challenges of quantifying non-financial metrics of performance.The final key outcome of this study centres on the development of a holistic model conceptualising the economics of quality management in the hotel industry. The key outputs of this model, such as the theoretical framework, the interdisciplinary research approach, and the conceptualisation of the economics of quality logic in hospitality, illuminate how the initial conceptual framework has been modified, and most importantly, what new knowledge has been integrated based on the empirical findings.Theoretical conclusionsIn exploring and conceptualising the economics of quality management, this study adds specifically to the body of knowledge around; a) the complex constructs of quality management and performance measurement, b) the perceptions and implementation of a systems approach to quality management, and c) quantifying the key facets of quality management on hotel operations. In addition to these key contributions to the literature, this doctoral research also builds on and adds new knowledge through the interdisciplinary lens of services marketing and management, tourism economics and financial management in exploring the economics of quality management in the hotel industry.This study’s theoretical framework creates a valuable basis for establishing the key resources of a hotel’s quality management efforts before measuring the financial impact of these quality resources on a firm’s operation. Hence, this study’s theoretical framework, within the overall integrated model of the economics of quality management, fills a gap by providing a means for empirically exploring the interrelationship between quality management, productivity, and profitability, via an analysis of the inputs and outputs of key quality resources utilised by hotels.Practical application of the dissertationThis study makes several significant contributions to practice and management because of the inference transferability and analytical generalisation of the statistical procedures employed in the single-case analysis of Hotel X. This is pertinent in terms of the measures employed to determine the financial impact of quality-related resources on firm performance. This study illuminated how the hotel industry’s high operating leverage which naturally results in sensitivities to variations in demand can challenge a hotel’s quality efforts. Singal (2015) attributes this to the industry’s unique structural characteristics, such as competition, risk, leverage, and capital intensity, in addition to the labour intensity of a hotel’s workforce and the low switching costs for consumers. The empirical work drew similar conclusions by revealing the market-orientated/revenue-driven approach of the single-case analysis because of its high fixed cost structure. However, this approach reflected positively on the hotel’s quality efforts as opposed to assuming a cost only orientated style of management.The implications drawn from the self-administered questionnaire findings provide several practical implications for management considering the negative perceptions identified of a systems approach to quality management in hospitality. This study concludes that traditional approaches to formalisedQMSs and practices in hotel companies do not reflect the relative importance of non-financial gauges, especially those related to quality management. This knowledge has also wider implications on global service operations and tourism policymakers in planning strategic quality initiatives
The impact of hyperlinks, skim reading and perceived importance when reading on the Web
No full textIt has previously been shown that readers spend a great deal of time skim reading on the Web and that this type of reading can affect comprehension of text. Across two experiments, we examine how hyperlinks influence perceived importance of sentences and how perceived importance in turn affects reading behaviour. In Experiment 1, participants rated the importance of sentences across passages of Wikipedia text. In Experiment 2, a different set of participants read these passages while their eye movements were tracked, with the task being either reading for comprehension or skim reading. Reading times of sentences were analysed in relation to the type of task and the importance ratings from Experiment 1. Results from Experiment 1 show readers rated sentences without hyperlinks as being of less importance than sentences that did feature hyperlinks, and this effect is larger when sentences are lower on the page. It was also found that short sentences with more links were rated as more important, but only when they were presented at the top of the page. Long sentences with more links were rated as more important regardless of their position on the page. In Experiment 2, higher importance scores resulted in longer sentence reading times, measured as fixation durations. When skim reading, however, importance ratings had a lesser impact on online reading behaviour than when reading for comprehension. We suggest readers are less able to establish the importance of a sentence when skim reading, even though importance could have been assessed by information that would be fairly easy to extract (i.e. presence of hyperlinks, length of sentences, and position on the screen)