6,143 research outputs found
Secure Short-Packet Communications via UAV-Enabled Mobile Relaying: Joint Resource Optimization and 3D Trajectory Design
Short-packet communication (SPC) and unmanned aerial vehicles (UAVs) are
anticipated to play crucial roles in the development of 5G-and-beyond wireless
networks and the Internet of Things (IoT). In this paper, we propose a secure
SPC system, where a UAV serves as a mobile decode-and-forward (DF) relay,
periodically receiving and relaying small data packets from a remote IoT device
to its receiver in two hops with strict latency requirements, in the presence
of an eavesdropper. This system requires careful optimization of important
design parameters, such as the coding blocklengths of both hops, transmit
powers, and UAV's trajectory. While the overall optimization problem is
nonconvex, we tackle it by applying a block successive convex approximation
(BSCA) approach to divide the original problem into three subproblems and solve
them separately. Then, an overall iterative algorithm is proposed to obtain the
final design with guaranteed convergence. Our proposed low-complexity algorithm
incorporates 3D trajectory design and resource management to optimize the
effective average secrecy throughput of the communication system over the
course of UAV-relay's mission. Simulation results demonstrate significant
performance improvements compared to various benchmark schemes and provide
useful design insights on the coding blocklengths and transmit powers along the
trajectory of the UAV
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The impact of employees' working relations in creating and retaining trust: the case of the Bahrain Olympic Committee
Introduction: This thesis investigates the impact of employees’ working relations in creating, maintaining and retaining trust in the Bahrain Olympic Committee (BOC).
Aim: The main aim of this thesis is to determine how the three groups of Organisational Trust variables, namely Social System Elements (SSE), Factors of Trustworthiness (FoT) and Third-Party Gossip (TPG), affect employees’ Organisational Trust (OTR) in the BOC and promote Organisational Citizenship Behaviour (OCB). To answer this main aim, a conceptual framework was created that focused on exploring the following research aims: (1) the interrelationship between SSE and FoT, (2) the effect of SSE on OTR, (3) the impact of TPG on OTR and (4) the effect of OTR on overall OCB.
Methodology: The study uses a mixed-method case study research style that included in-depth semi-structured interviews with 17 managers, an online questionnaire survey with 320 employees of the BOC and an analysis of the BOC’s Annual Reports from 2015 to 2018.
Results: The qualitative and quantitative findings indicate, firstly, that there is a significant interrelationship between SSE and FoT, establishing that SSE’s perception of organisational justice (OJ), including that FoTs benevolence and integrity as the most important factors in yielding employees’ trust in the BOC. Secondly, it has been established that SSEs have significant direct and indirect effects on OTR. Thirdly, negative and positive TPG concurrently occurred in the BOC and the prevalence of negative TPG poses more impact on OTR. Finally, this study’s findings demonstrated OTR’s effect in generating OCB, including that Civic Virtue was rated as the most preferred of the five OCB themes; this indicates the managers’ and the employees’ strong emotional attachment and support of the activities taking place at the BOC.
Contributions: Overall, this thesis substantially contributes to OTR literature, particularly in the context of the Middle East. It also proposes several insightful recommendations for future research and practical implications for practitioners in the field of Organisational Trust
Boundary Spanner Corruption in Business Relationships
Boundary spanner corruption—voluntary collaborative behaviour between individuals representing different organisations that violates their organisations’ norms—is a serious problem in business relationships. Drawing on insights from the literatures on general corruption perspectives, the dark side of business relationships and deviance in sales and service organisations, this dissertation identifies boundary spanner corruption as a potential dark side complication inherent in close business relationships It builds research questions from these literature streams and proposes a research structure based upon commonly used methods in corruption research to address this new concept. In the first study, using an exploratory survey of boundary spanner practitioners, the dissertation finds that the nature of boundary spanner corruption is broad and encompasses severe and non-severe types. The survey also finds that these deviance types are prevalent in a widespread of geographies and industries. This prevalence is particularly noticeable for less-severe corruption types, which may be an under-researched phenomenon in general corruption research. The consequences of boundary spanner corruption can be serious for both individuals and organisations. Indeed, even less-severe types can generate long-term negative consequences. A second interview-based study found that multi-level trust factors could also motivate the emergence of boundary spanner corruption. This was integrated into a theoretical model that illustrates how trust at the interpersonal, intraorganisational, and interorganisational levels enables corrupt behaviours by allowing deviance-inducing factors stemming from the task environment or from the individual boundary spanner to manifest in boundary spanner corruption. Interpersonal trust between representatives of different organisations, interorganisational trust between these organisations, and intraorganisational agency trust of management in their representatives foster the development of a boundary-spanning social cocoon—a mechanism that can inculcate deviant norms leading to corrupt behaviour. This conceptualisation and model of boundary spanner corruption highlights intriguing directions for future research to support practitioners engaged in a difficult problem in business relationships
SWIPT aided Cooperative Communications with Energy Harvesting based Selective-Decode-and-Forward Protocol: Benefiting from Channel Aging Effect
Simultaneous wireless information and power transfer (SWIPT) in radio-frequency (RF) bands enables flexible deployment of battery-powered relays for extending communication coverage. Relays receive downlink RF signals emitted by a source for information decoding and energy harvesting, while the harvested energy is consumed for both information decoding and information forwarding to a destination. An energy harvesting based selective-decode-and-forward (EH-SDF) protocol is proposed, where only the relays having information correctly decoded are activated for information forwarding, while others harvest and store energy for the future use. By considering the channel aging effect, we propose a joint relay selection, power allocation, transmit beamforming and signal splitting design in order to maximise the end-to-end (e2e) throughput of this EH-SDF aided cooperative communication system. Two scenarios with/without direct link between the source and the destination are studied, respectively. The original formulated non-convex optimisation problems with coupled variables are decoupled into three subproblems which are solved by an iterative optimisation algorithm. Numerical results demonstrate that our design with the EH-SDF protocol achieves a higher e2e throughput than the traditional decode-and-forward (DF) counterpart. Moreover, the impact of the channel aging effect on the e2e throughput is also evaluated
A Systematic Review on Teacher Digital Literacy in Higher Education
In order to conduct a conceptual review, and to discover the topics and categories of research, this study firstly searches the Google Scholar database, and then conducts a specific analysis of the 17 publications, hoping to explore the overall research that constitutes the topic of digital literacy for teachers in the university setting, to understand whether the concept needs to be continuously defined. The relative theoretical framework and key components to guide teacher digital literacy in the context of higher education have not yet been formed. It is necessary to continue to review the concept and key components of digital literacy for teachers in higher education in the future, providing a perspective for digital transformation research in higher education institutions
Financial reporting in Europe: Accounting for regulatory and technical challenges
This thesis explores the challenges facing financial reporting in Europe both regulatory and technical in nature. This has involved research into the background of European legislation and conducting face to face semi-structured interviews with senior elite actors from institutions governing the regulatory and technical arrangements of general-purpose financial reporting practice in Europe. European companies are required to disclose information about their financial affairs. The European legislation governing company financial reporting was delegated to the International Accounting Standards Board (IASB) by the EU institutions via Regulation 1606/2002. This thesis argues that European agencies (represented by EFRAG) are caught in a devolved regulatory relationship where the International Accounting Standards Board (IASB) has been able to assume a relatively strong self-regulatory position. This weakens the agency that European legislative institutions have over their own legislation with regards to financial reporting practice. This thesis argues this loss of agency by European institutions over their legislation governing accounting practice is not a fait accompli but is challenged and contested as European institutions seek and need a more co-regulated arrangement. A key argument developed in this thesis is that regulatory arrangements governing accounting practice are evolving in terms of the distribution of responsibilities and control over European financial reporting practice. To understand how the regulatory landscape governing European accounting practice is changing we employ an investigative lens that is grounded in accounting. This investigative lens employs three elements that are regarded in the literature review as significant technical challenges facing accounting practice in Europe. The first of these is retaining or not prudent accounting practice, the second is concerned with the development of non-financial reporting and the third, concerns with installing the public interest not just investor interests in financial disclosures. It is through this investigative lens that this thesis assesses the extent to which regulatory arrangements and agency governing accounting practice in Europe are shifting sands
Information Security Using DNA Sequences
يعد أمن المعلومات من المواضيع المهمة، ويرجع ذلك أساسًا إلى النمو الهائل في استخدام الإنترنت على مدى السنوات القليلة الماضية. نتيجة لهذا النمو، كانت هناك حالات وصول غير مصرح به، والتي تم تقليلها بفضل "استخدام مجموعة من بروتوكولات الاتصال الآمن، مثل التشفير وإخفاء البيانات". باستخدام القدرات الجزيئية الحيوية للحمض النووي، ازداد استخدام الحمض النووي كناقل للتشفير وإخفاء البيانات في السنوات الأخيرة. أثار إدراك أن الحمض النووي قد يعمل كوسيط نقل أثار هذه الحركة. في هذه الدراسة، نفحص أولاً ونلخص بإيجاز تطور نظام ترميز الحمض النووي الحالي. بعد ذلك، يتم تصنيف الطرق العديدة التي تم بها استخدام الحمض النووي لتحسين تقنيات التشفير. تمت مناقشة مزايا وعيوب هذه الخوارزميات وأحدث التطورات في تقنيات التشفير القائم على الحمض النووي. أخيرًا، نقدم أفكارنا حول المستقبل المحتمل لخوارزميات التشفير القائمة على الحمض النووي.Information security is a significant cause for concern, mainly because of the explosive growth in internet usage over the last few years. Due to this growth, there have been occurrences of unauthorized access, which have been reduced thanks to “using a range of secure communication protocols, such as encryption and data concealment”. Using DNA's bio-molecular capabilities, the usage of DNA as a carrier for encryption and data concealing has increased in recent years. The realization that DNA may function as a transport medium sparked this movement. In this study, we first examine and briefly outline the evolution of the present DNA coding system. After that, the several ways DNA has been used to enhance encryption techniques are categorized. The benefits and drawbacks of these algorithms and the most recent advancements in DNA-based encryption techniques are discussed. Finally, we provide our thoughts on the potential future of DNA-based encryption algorithms.
 
Prime Match: A Privacy-Preserving Inventory Matching System
Inventory matching is a standard mechanism for trading financial stocks by which buyers and sellers can be paired. In the financial world, banks often undertake the task of finding such matches between their clients. The related stocks can be traded without adversely impacting the market price for either client. If matches between clients are found, the bank can offer the trade at advantageous rates. If no match is found, the parties have to buy or sell the stock in the public market, which introduces additional costs.
A problem with the process as it is presently conducted is that the involved parties must share their order to buy or sell a particular stock, along with the intended quantity (number of shares), to the bank. Clients worry that if this information were to “leak” somehow, then other market participants would become aware of their intentions and thus cause the price to move adversely against them before their transaction finalizes.
We provide a solution, Prime Match, that enables clients to match their orders efficiently with reduced market impact while maintaining privacy. In the case where there are no matches, no information is revealed. Our main cryptographic innovation is a two-round secure linear comparison protocol for computing the minimum between two quantities without preprocessing and with malicious security, which can be of independent interest. We report benchmarks of our Prime Match system, which runs in production and is adopted by a large bank in the US -- J.P. Morgan. The system is designed utilizing a star topology network, which provides clients with a centralized node (the bank) as an alternative to the idealized assumption of point-to-point connections, which would be impractical and undesired for the clients to implement in reality.
Prime Match is the first secure multiparty computation solution running live in the traditional financial world
Performance Analysis of Discrete-Phase-Shifter IRS-aided Amplify-and-Forward Relay Network
As a new technology to reconfigure wireless communication environment by
signal reflection controlled by software, intelligent reflecting surface (IRS)
has attracted lots of attention in recent years. Compared with conventional
relay system, the relay system aided by IRS can effectively reduce the cost and
energy consumption, and significantly enhance the system performance. However,
the phase quantization error generated by IRS with discrete phase shifter may
degrade the receiving performance of the receiver. To analyze the performance
loss caused by IRS phase quantization error, based on the law of large numbers
and Rayleigh distribution, the closed-form expressions for the signal-to-noise
ratio (SNR) performance loss and achievable rate of the IRS-aided
amplify-and-forward (AF) relay network, which are related to the number of
phase shifter quantization bits, are derived under the line-of-sight (LoS)
channels and Rayleigh channels, respectively. Moreover, their approximate
performance loss closed-form expressions are also derived based on the Taylor
series expansion. Simulation results show that the performance losses of SNR
and achievable rate decrease with the number of quantization bits increases
gradually. When the number of quantization bits is larger than or equal to 3,
the SNR performance loss of the system is smaller than 0.23dB, and the
achievable rate loss is less than 0.04bits/s/Hz, regardless of the LoS channels
or Rayleigh channels
Imagining Iberia in English and Castilian Medieval Romance
Imagining Iberia in English and Castilian Medieval Romance offers a broad disciplinary, linguistic, and national focus by analyzing the literary depiction of Iberia in two European vernaculars that have rarely been studied together. Emily Houlik-Ritchey employs an innovative comparative methodology that integrates the understudied Castilian literary tradition with English literature. Intentionally departing from the standard “influence and transmission” approach, Imagining Iberia challenges that standard discourse with modes drawn from Neighbor Theory to reveal and navigate the relationships among three selected medieval romance traditions. This welcome volume uncovers an overemphasis in prior scholarship on the relevance of “crusading” agendas in medieval romance, and highlights the shared investments of Christians and Muslims in Iberia’s political, creedal, cultural, and mercantile networks in the Mediterranean world
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