Macro- and micro-strain in GaN nanowires on Si(111)

We analyze the strain state of GaN nanowire ensembles by x-ray diffraction. The nanowires are grown by molecular beam epitaxy on a Si(111) substrate in a self-organized manner. On a macroscopic scale, the nanowires are found to be free of strain. However, coalescence of the nanowires results in micro-strain with a magnitude from +-0.015% to +-0.03%.This micro-strain contributes to the linewidth observed in low-temperature photoluminescence spectra

Maskin-Monotonic Scoring Rules

Cataloged from PDF version of article.We characterize which scoring rules are Maskin-monotonic for each social choice problem as a function of the number of agents and the number of alternatives. We show that a scoring rule is Maskin-monotonic if and only if it satisfies a certain unanimity condition. Since scoring rules are neutral, Maskin-monotonicity turns out to be equivalent to Nash-implementability within the class of scoring rules. We propose a class of mechanisms such that each Nash-implementable scoring rule can be implemented via a mechanism in that class. Moreover, we investigate the class of generalized scoring rules and show that with a restriction on score vectors, our results for the standard case are still valid

Error resilient video transcoding for robust inter-network communications using GPRS

A novel fully comprehensive mobile video communications system is proposed in this paper. This system exploits the useful rate management features of the video transcoders and combines them with error resilience for transmissions of coded video streams over general packet radio service (GPRS) mobileaccess networks. The error-resilient video transcoding operation takes place at a centralized point, referred to as a video proxy, which provides the necessary output transmission rates with the required amount of robustness. With the use of this proposed algorithm, error resilience can be added to an already compressed video stream at an intermediate stage at the edge of two or more different networks through two resilience schemes, namely the adaptive intra refresh (AIR) and feedback control signaling (FCS) methods. Both resilience tools impose an output rate increase which can also be prevented with the proposed novel technique in this paper. Thus, an error-resilient video transcoding scheme is presented to give robust video outputs at near target transmission rates that only require the same number of GPRS timeslots as the nonresilient schemes. Moreover, an ultimate robustness is also accomplished with the combination of the two resilience algorithms at the video proxy. Extensive computer simulations demonstrate the effectiveness of the proposed system

UX Research is Dead. Long live UX Research!

This paper critically discusses the future of User Experience (UX) research across the tech industry and hence the shift from classic usability research towards design-led approaches, quantitative research discipline, A/B testing and telemetry. Likely causes for this shift are addressed to empower the UX research discipline to remain relevant. The areas covered include the identity crisis and democratization of UX research; evolvement and sustainability of the UX discipline; and fusion of UX across heterogeneous fields. The adaptations to this shift are discussed from the Point of View (PoV) of practitioners. This includes offering clarity and meaning based on the organizational context and product positioning; and also leveraging deep understanding human behavior with a focus on data integrity that relates to the technology and environment

Problem-Oriented Conceptual Model and Ontology for Enterprise e-Recruitment

Internet-led labour market has become so competitive forcing many organisations from different sectors to embrace e-recruitment. However, realising the value of the e-recruitment from a Requirements Engineering (RE) analysis perspective is challenging. The research is motivated by the results of a failed e-recruitment project as a case study by focusing on the difficulty of scoping and representing recruitment problem knowledge to systematically inform the RE process towards an e-recruitment solution specification. In this paper, a Problem-Oriented Conceptual Model (POCM) supported by an Ontology for Recruitment Problem Definition (Onto-RPD) for contextualisation of the enterprise e-recruitment problem space is presented. Inspired by Soft Systems Methodology (SSM), the POCM and Onto-RPD are produced based on the detailed analysis of three case studies: (1) Secureland Army Enlistment, (2) British Army Regular Enlistment, and (3) UK Undergraduate Universities and Colleges Admissions Service (UCAS). The POCM and the ontology are demonstrated and evaluated by a focus group against a set of criteria. The evaluation showed a valuable contribution of the POCM in representing and understanding the recruitment problem and its complexity

Retrospective Cost Adaptive Control for Systems with Unknown Nonminimum-Phase Zeros

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90721/1/AIAA-2011-6203-626.pd

Human-Centred Design for Intelligent Environments: Preface to the proceedings of the workshop on Human Centred Design for Intelligent Environments.

Preface to the proceedings of the workshop on “Human Centred Design for Intelligent Environments” organised in conjunction with the 2016 BCS British HCI Conference held at Bournemouth University, July 11th-15th 2016

Have Usability and Security Trade-offs in Mobile Financial Services (MFS) become Untrustworthy?

The trade-off between Usability and Security has been well researched with various models proposed on how best to improve Usability without jeopardizing Security and vice visa. Usable Security has become a key factor in Mobile Financial Services (MFS), the new frontier for mobile phones utilisation. However, have the compromises gone too far? The trustworthiness of MFS system has already slowed down new adoption and impacted ongoing security trust issues and user confidence in spite of potential MFS benefits for its users. To understand this growing lack of trust with MFS, we need to comprehend the nature of Usable Security in assuring the behaviours of MFS users and determine the right trade-off to improve trust whilst facilitating future uptake. We conducted an empirical survey of 698 user’s experience of MFS and here present our findings of this investigation for further synthesis towards proposing practical control elements to assure Usable Security in MFS