Integration Of Strength and Process Modelling of Friction-Stir-Welded Fuselage Panels

In order to reduce potential uncertainties and conservatism in welded panel analysis procedures, understanding of the relationships between welding process parameters and static strength is required. The aim of this study is to determine and characterize the key process induced properties of advanced welding assembly methods on stiffened panel local buckling and collapse performance. To this end, an in-depth experimental and computational study of the static strength of a friction stir welded fuselage skin-stiffener panel subjected to compression loading has been undertaken. Four welding process effects, viz. the weld joint width, the width of the weld Heat Affected Zone, the strength of material within the weld Heat Affected Zone and the magnitude of welding induced residual stress, are investigated. A fractional factorial experiment design method (Taguchi) has been applied to identify the relative importance of each welding process effect and investigate effect interactions on both local skin buckling and crippling collapse performance. For the identified dominant welding process effects, parametric studies have been undertaken to identify critical welding process effect magnitudes and boundaries. The studies have shown that local skin buckling is principally influenced by the magnitude of welding induced residual stress and that the strength of material in the Heat Affected Zone and the magnitude of the welding induced residual stress have the greatest influence on crippling collapse behavior.


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Client's assessment of architects' performance in building delivery process: Evidence from Nigeria

The overall intent of this research is to provide architects with information that can be used to improve their performance so as to optimally satisfy the client's requirements and achieve high-quality overall project performance in Nigerian construction industry. Architect performance criteria were identified based on literature within the domain of architect responsibilities. The assessment of architects’ performance was carried out through a questionnaire survey of clients of recently completed building projects in Nigeria. Analysis of data includes comparison of criteria using importance–performance index analysis. Factor analysis was carried out on criteria where architects are falling below average, to group and explore the latent structure of the criteria in the data. The results showed that the architect needs to focus on management skills and ability, buildability, design quality, project communication, project integration and client focus. These results would encourage architects to perform better within their full responsibilities in the building delivery process and deliver high-quality projects within Nigerian construction industry.

COMMUNICATION AND GREEK ENVIRONMENTAL ORGANISATIONS: MEANS OF COMMUNICATION AND INFLUENCING FACTORS

A basic operational objective of any environmental organisation is to raise awareness among the public on issues of environmental protection, through the dissemination of knowledge and experience to local communities, so that the conservation and ecologically sound management of natural resources can acquire a local dimension. This can be achieved either through interventions directed at the State, mainly in relation to its legislative function, or by encouraging citizens to change or improve their attitude regarding environmental matters. In order to ensure a successful outcome and the efficient functioning of any organisation, a feeling of mutual trust and understanding should exist between the latter and its various audiences, i.e. the State and society. A basic ingredient of this balance between the organisation, the broader public and the State is effective communication and activity planning. As a way of contributing to the exploration of this process, this paper describes the means of communication used by Greek environmental organisations, and presents, through a non-linear model, the differentiation amongst them, in conjunction with aspects of the profile of those running each organisation and other indicators, such as the years in operation and the membership figures in each sampled organisation. The paper concludes by arguing that the diversification of communication means is related to the head person's years as a member of the organisation and the extent of its total membership. Another important finding is that the more the involvement in activities within the organisation, the less differentiation we observe amongst the employed means of communication.

A Competence-Based Post-Disaster Reconstruction Process: Findings from Sri Lanka

As natural disasters continue to escalate in frequency and magnitude, NGOs are faced with numerous barriers as they attempt to implement post-disaster reconstruction (PDR) projects. In many cases, a lack of competency in key areas leads to a reduction in overall project success. This paper utilizes the competency-based framework of von Meding et al. (2010) as the starting point of its inquiry. In this context, a leading NGO responsible for the implementation of reconstruction and rehabilitation in Sri Lanka following the Asian Tsunami has been investigated in depth using a causal mapping interview procedure with key project staff. The combined barriers within this organization’s PDR operations have been identified and measured and solutions articulated. The study found that within this organization key objectives were to achieve the ‘build back better’ mantra and to effectively plan interventions in advance. The primary barriers to successful reconstruction were identified as the high turnover rate of humanitarian staff and a poor level of communication and co-operation between agencies. An essential strategy employed to combat these barriers is the consideration of staff capabilities, which links us back to competence-based theory. The results are highly valuable in the context of an ongoing wider research study on competence within humanitarian organizations.

A dynamic sampling methodology for plasma etch processes using Gaussian process regression

Plasma etch is a key process in modern semiconductor manufacturing facilities as it offers process simplification and yet greater dimensional tolerances compared to wet chemical etch technology. The main challenge of operating plasma etchers is to maintain a consistent etch rate spatially and temporally for a given wafer and for successive wafers processed in the same etch tool. Etch rate measurements require expensive metrology steps and therefore in general only limited sampling is performed. Furthermore, the results of measurements are not accessible in real-time, limiting the options for run-to-run control. This paper investigates a Virtual Metrology (VM) enabled Dynamic Sampling (DS) methodology as an alternative paradigm for balancing the need to reduce costly metrology with the need to measure more frequently and in a timely fashion to enable wafer-to-wafer control. Using a Gaussian Process Regression (GPR) VM model for etch rate estimation of a plasma etch process, the proposed dynamic sampling methodology is demonstrated and evaluated for a number of different predictive dynamic sampling rules. © 2013 IEEE.

'Conditional candour' and 'knowing me': an interpretive description study on patient preferences for physician behaviours during end-of-life communication

OBJECTIVE: To understand patients' preferences for physician behaviours during end-of-life communication.

METHODS: We used interpretive description methods to analyse data from semistructured, one-on-one interviews with patients admitted to general medical wards at three Canadian tertiary care hospitals. Study recruitment took place from October 2012 to August 2013. We used a purposive, maximum variation sampling approach to recruit hospitalised patients aged ≥55 years with a high risk of mortality within 6-12 months, and with different combinations of the following demographic variables: race (Caucasian vs non-Caucasian), gender and diagnosis (cancer vs non-cancer).

RESULTS: A total of 16 participants were recruited, most of whom (69%) were women and 70% had a non-cancer diagnosis. Two major concepts regarding helpful physician behaviour during end-of-life conversations emerged: (1) 'knowing me', which reflects the importance of acknowledging the influence of family roles and life history on values and priorities expressed during end-of-life communication, and (2) 'conditional candour', which describes a process of information exchange that includes an assessment of patients' readiness, being invited to the conversation, and sensitive delivery of information.

CONCLUSIONS: Our findings suggest that patients prefer a nuanced approach to truth telling when having end-of-life discussions with their physician. This may have important implications for clinical practice and end-of-life communication training initiatives.

Measuring horizontal integration among health care providers in the community: An examination of a collaborative process within a palliative care network

In many countries formal or informal palliative care networks (PCNs) have evolved to better integrate community-based services for individuals with a life-limiting illness. We conducted a cross-sectional survey using a customized tool to determine the perceptions of the processes of palliative care delivery reflective of horizontal integration from the perspective of nurses, physicians and allied health professionals working in a PCN, as well as to assess the utility of this tool. The process elements examined were part of a conceptual framework for evaluating integration of a system of care and centred on interprofessional collaboration. We used the Index of Interdisciplinary Collaboration (IIC) as a basis of measurement. The 86 respondents (85% response rate) placed high value on working collaboratively and most reported being part of an interprofessional team. The survey tool showed utility in identifying strengths and gaps in integration across the network and in detecting variability in some factors according to respondent agency affiliation and profession. Specifically, support for interprofessional communication and evaluative activities were viewed as insufficient. Impediments to these aspects of horizontal integration may be reflective of workload constraints, differences in agency operations or an absence of key structural features.

Cross-layer Energy-Efficiency Optimization of Packet Based Wireless MIMO Communication Systems

Energy in today's short-range wireless communication is mostly spent on the analog- and digital hardware rather than on radiated power. Hence,purely information-theoretic considerations fail to achieve the lowest energy per information bit and the optimization process must carefully consider the overall transceiver. In this paper, we propose to perform cross-layer optimization, based on an energy-aware rate adaptation scheme combined with a physical layer that is able to properly adjust its processing effort to the data rate and the channel conditions to minimize the energy consumption per information bit. This energy proportional behavior is enabled by extending the classical system modes with additional configuration parameters at the various layers. Fine grained models of the power consumption of the hardware are developed to provide awareness of the physical layer capabilities to the medium access control layer. The joint application of the proposed energy-aware rate adaptation and modifications to the physical layer of an IEEE802.11n system, improves energy-efficiency (averaged over many noise and channel realizations) in all considered scenarios by up to 44%.

Review of the area planning process (a)

The area planning process continues and formal recommendations arising from it are now being brought forward as development proposals to amalgamate or close schools. At this point in the process the Education Committee requested some comment on five different aspects of the process: the impact of Area Planning to date; the validity of the surplus school vacancy calculation methodology; the Annual Area Profile information; the Needs Model (including as appropriate the implications of the Drumragh judgement); possible enhancements to the consultation and communication process;the facilitation of alternative cross-sectoral or cross-border solutions. This paper offers high level comment on each of these issues. In addition, the Education Committee facilitated a stakeholder consultation meeting in Parliament Buildings on 4 February, 2015. The broad themes that emerged in that discussion will also be mentioned in this paper.

Interactive management control via analytic hierarchy process (AHP). An empirical study in a public university hospital

Management control in public university hospitals is a challenging task because of continuous changes due to external pressures (e.g. economic pressures, stakeholder focuses and scientific progress) and internal complexities (top management turnover, shared leadership, technological evolution, and researcher oriented mission). Interactive budgeting contributed to improving vertical and horizontal communication between hospital and stakeholders and between different organizational levels. This paper describes an application of Analytic Hierarchy Process (AHP) to enhance interactive budgeting in one of the biggest public university hospital in Italy. AHP improved budget allocation facilitating elicitation and formalization of units' needs. Furthermore, AHP facilitated vertical communication among manager and stakeholders, as it allowed multilevel hierarchical representation of hospital needs, and horizontal communication among staff of the same hospital, as it allowed units' need prioritization and standardization, with a scientific multi-criteria approach, without using complex mathematics. Finally, AHP allowed traceability of a complex decision making processes (as budget allocation), this aspect being of paramount importance in public sectors, where managers are called to respond to many different stakeholders about their choices.

Polarization effects in fiber-optic communication systems

In this thesis we perform a detailed analysis of the state of polarization (SOP) of light scattering process using a concatenation of ber-coil based polarization controllers (PCs). We propose a polarization-mode dispersion (PMD) emulator, built through the concatenation of bercoil based PCs and polarization-maintaining bers (PMFs), capable of generate accurate rst- and second-order PMD statistics. We analyze the co-propagation of two optical waves inside a highbirefringence ber. The evolution along the ber of the relative SOP between the two signals is modeled by the de nition of the degree of co-polarization parameter. We validate the model for the degree of co-polarization experimentally, exploring the polarization dependence of the four-wave mixing e ect into a ber with high birefringence. We also study the interaction between signal and noise mediated by Kerr e ect in optical bers. A model accurately describing ampli ed spontaneous emission noise in systems with distributed Raman gain is derived. We show that the noise statistics depends on the propagation distance and on the signal power, and that for distances longer than 120 km and signal powers higher than 6 mW it deviates signi catively from the Gaussian distribution. We explore the all-optical polarization control process based on the stimulated Raman scattering e ect. Mapping parameters like the degree of polarization (DOP), we show that the preferred ampli cation of one particular polarization component of the signal allows a polarization pulling over a wavelength range of 60 nm. The e ciency of the process is higher close to the maximum Raman gain wavelength, where the DOP is roughly constant for a wavelength range of 15 nm. Finally, we study the polarization control in quantum key distribution (QKD) systems with polarization encoding. A model for the quantum bit error rate estimation in QKD systems with time-division multiplexing and wavelength-division multiplexing based polarization control schemes is derived.

Beyond the artefact and techno-centricity: towards process-centric understanding of architecture - alternative facilitation strategies and proposals

The artefact and techno-centricity of the research into the architecture process needs to be counterbalanced by other approaches. An increasing amount of information is collected and used in the process, resulting in challenges related to information and knowledge management, as this research evidences through interviews with practicing architects. However, emerging technologies are expected to resolve many of the traditional challenges, opening up new avenues for research. This research suggests that among them novel techniques addressing how architects interact with project information, especially that indirectly related to the artefacts, and tools which better address the social nature of work, notably communication between participants, become a higher priority. In the fields associated with the Human Computer Interaction generic solutions still frequently prevail, whereas it appears that specific alternative approaches would be particularly in demand for the dynamic and context dependent design process. This research identifies an opportunity for a process-centric and integrative approach for architectural practice and proposes an information management and communication software application, developed for the needs discovered in close collaboration with architects. Departing from the architects’ challenges, an information management software application, Mneme, was designed and developed until a working prototype. It proposes the use of visualizations as an interface to provide an overview of the process, facilitate project information retrieval and access, and visualize relationships between the pieces of information. Challenges with communication about visual content, such as images and 3D files, led to a development of a communication feature allowing discussions attached to any file format and searchable from a database. Based on the architects testing the prototype and literature recognizing the subjective side of usability, this thesis argues that visualizations, even 3D visualizations, present potential as an interface for information management in the architecture process. The architects confirmed that Mneme allowed them to have a better project overview, to easier locate heterogeneous content, and provided context for the project information. Communication feature in Mneme was seen to offer a lot of potential in design projects where diverse file formats are typically used. Through empirical understanding of the challenges in the architecture process, and through testing the resulting software proposal, this thesis suggests promising directions for future research into the architecture and design process.

Miniaturization and Integration of Optoelectronics for Contact Lens Embedded Display and Wireless Communication

Thesis (Ph.D.)--University of Washington, 2013

LNT: a logical neighbor tree secure group communication scheme for wireless sensor networks

Secure group communication is a paradigm that primarily designates one-to-many communication security. The proposed works relevant to secure group communication have predominantly considered the whole network as being a single group managed by a central powerful node capable of supporting heavy communication, computation and storage cost. However, a typical Wireless Sensor Network (WSN) may contain several groups, and each one is maintained by a sensor node (the group controller) with constrained resources. Moreover, the previously proposed schemes require a multicast routing support to deliver the rekeying messages. Nevertheless, multicast routing can incur heavy storage and communication overheads in the case of a wireless sensor network. Due to these two major limitations, we have reckoned it necessary to propose a new secure group communication with a lightweight rekeying process. Our proposal overcomes the two limitations mentioned above, and can be applied to a homogeneous WSN with resource-constrained nodes with no need for a multicast routing support. Actually, the analysis and simulation results have clearly demonstrated that our scheme outperforms the previous well-known solutions.

A complex protocol layer as a linux user-space process

With the current complexity of communication protocols, implementing its layers totally in the kernel of the operating system is too cumbersome, and it does not allow use of the capabilities only available in user space processes. However, building protocols as user space processes must not impair the responsiveness of the communication. Therefore, in this paper we present a layer of a communication protocol, which, due to its complexity, was implemented in a user space process. Lower layers of the protocol are, for responsiveness issues, implemented in the kernel. This protocol was developed to support large-scale power-line communication (PLC) with timing requirements.