On Modified Method of Simplest Equation for Obtaining Exact Solutions of Nonlinear PDEs: Case of Elliptic Simplest Equation

2010 Mathematics Subject Classification: 74J30, 34L30.

Local-Median Method of Forecasting for Regression Time Series under Outliers

2002 Mathematics Subject Classification: 62M20, 62-07, 62J05, 62P20.

A method of fundamental solutions for radially symmetric and axisymmetric backward heat conduction problems

We propose and investigate an application of the method of fundamental solutions (MFS) to the radially symmetric and axisymmetric backward heat conduction problem (BHCP) in a solid or hollow cylinder. In the BHCP, the initial temperature is to be determined from the temperature measurements at a later time. This is an inverse and ill-posed problem, and we employ and generalize the MFS regularization approach [B.T. Johansson and D. Lesnic, A method of fundamental solutions for transient heat conduction, Eng. Anal. Boundary Elements 32 (2008), pp. 697–703] for the time-dependent heat equation to obtain a stable and accurate numerical approximation with small computational cost.

A method of fundamental solutions for theaxisymmetric backward heat equation

We propose and investigate an application of the method of fundamental solutions (MFS) to the radially symmetric and axisymmetric backward heat conduction problem (BHCP) in a solid or hollow cylinder. In the BHCP, the initial temperature is to be determined from the temperature measurements at a later time. This is an inverse and ill-posed problem, and we employ and generalize the MFS regularization approach [B.T. Johansson and D. Lesnic, A method of fundamental solutions for transient heat conduction, Eng. Anal. Boundary Elements 32 (2008), pp. 697–703] for the time-dependent heat equation to obtain a stable and accurate numerical approximation with small computational cost.

Conclusion : on multiple levels of analysis, context, contingency and capital

In this concluding chapter, we bring together the threads and reflections on the chapters contained in this text and show how they relate to multi-level issues. The book has focused on the world of Human Resource Management (HRM) and the systems and practices it must put in place to foster innovation. Many of the contributions argue that in order to bring innovation about, organisations have to think carefully about the way in which they will integrate what is, in practice, organisationally relevant — but socially distributed — knowledge. They need to build a series of knowledge-intensive activities and networks, both within their own boundaries and across other important external inter-relationships. In so doing, they help to co-ordinate important information structures. They have, in effect, to find ways of enabling people to collaborate with each other at lower cost, by reducing both the costs of their co-ordination and the levels of unproductive search activity. They have to engineer these behaviours by reducing the risks for people that might be associated with incorrect ideas and help individuals, teams and business units to advance incomplete ideas that are so often difficult to codify. In short, a range of intangible assets must flow more rapidly throughout the organisation and an appropriate balance must be found between the rewards and incentives associated with creativity, novelty and innovation, versus the risks that innovation may also bring.

Academic achievement orientation of West Indian American parents and adolescents

Literature addressing academic achievement orientation of Black adolescents in the United States often depicts poor school related attitudes and adaptation patterns, low academic achievement, and deficient family backgrounds. However, some researchers maintained that certain Black immigrant groups possessed positive academic achievement orientations and exemplary academic achievements (Ogbu, 1991; Gibson, 1991; Vernez, & Abrahamse, 1996). In this study, I attempted to combine qualitative data from multiple sources (surveys, interviews, observations, literature, and document analysis), using standard case study methodology and the constant comparative method of analysis to understand the relationship that existed between the academic achievement orientation of a select group of West Indian American parents and adolescents in Broward County, Florida. The sub-sample of 11 families, comprising 15 adolescents and 13 parents, was selected through maximum variation sampling from a pool of 23 families. The findings were presented as a single composite case study. The participants possessed specific, longstanding educational and career goals for the children. The parents were deeply involved and were knowledgeable of their children's schools and academic progress. While mothers were the parents most actively involved in the schools, fathers were strong authoritative figures. Families evidenced a strong moral religious base with set rules of behavior, firm parenting practices, and established chains of authority. Family members emphasized education over material things; reading over audiovisual or social activities; family cohesion over individual wishes; and academics over extracurricular activities. The parents' strong positive academic achievement orientation was communicated to the children and reinforced by relatives, family friends, and others. In turn, the adolescents possessed positive school-related attitudes and attributional styles. While they admitted their parents were somewhat strict, they voluntarily complied with the rules and were highly motivated to succeed because they believed their parents deeply cared for them and that education leads to success and upward mobility. Each adolescent was pursuing an academic track and planning for college and specific profession. The findings support Ogbu's cultural ecological model (1991). I recommend these findings to teachers, counselors, administrators, parents, and others working with West Indian American families. ^

How employees with different national identities experience a geocentric organizational culture of a global corporation: A phenomenological study

A global corporation values both profitability and social acceptance; its units mutually negotiate governance and represent a highly interdependent network where centers of excellence and high-potential employees are identified regardless of geographic locations. These companies try to build geocentric, or “world oriented” (Marquardt, 1999, p. 20), organizational cultures. Such culture “transcends cultural differences and establishes ‘beacons’ – values and attitudes – that are comprehensive and compelling” (Kets de Vries & Florent-Treacy, 2002, p. 299) for all employees, regardless of their national origins. Creating a geocentric organizational culture involves transforming each employee’s mindset, beliefs, and behaviors so that he/she can become “a world citizen in spite of having a national identity” (Marquardt, 1999, p. 47). The purpose of this phenomenological study was to explore how employees with different national identities experience a geocentric organizational culture of a global corporation. Phenomenological research aims to understand “how people experience some phenomenon—how they perceive it, describe it, feel about it, judge it, remember it, make sense of it, and talk about it with others” (Patton, 2002, p. 104). Twelve participants were selected using criteria, convenience, and snow-ball sampling strategies. A semi-structured interview guide was used to collect data. Data were analyzed inductively, using Moustakas’s (1994) Modification of the Stevick-Colaizzi-Keen Method of Analysis of Phenomenological Data. The participants in this study experienced a geocentric organizational culture of a global corporation as on in which they felt connected, valued, and growing personally and professionally. The participants felt connected to the companies via business goals and social responsibility. The participants felt valued by the company because their creativity was welcomed and they could contribute to the corporation certain unique knowledge of the culture and language of their native countries. The participants felt growing personally and professionally due to the professional development opportunities, cross-cultural awareness, and perspective consciousness. Based on the findings from this study, a model of a geocentric organizational culture of a global corporation: An employee perspective is proposed. Implications for research and practice conclude this study.

Island diasporas: Perceptions of Indo-Caribbean protégés regarding the effects of their cross-cultural mentoring experiences in the United States

Mentoring is defined as an "intense caring relationship in which persons with more experience work with less experienced persons to promote both professional and personal development" (Caffarella, 1992, p. 38). It is "a powerful emotional, and passionate interaction whereby the mentor and protégé experience...intellectual growth and development" (Galbraith & Zelenak, 1991, p. 126). In cross-cultural mentoring, mentors and protégés from different cultures confront social and cultural identities, goals, expectations, values, and beliefs (Cross & Lincoln, 2005) to "achieve a higher level of potency in education and society" (Mullen, 2005, p. 6). Cross-cultural mentoring research explores attitudes, behaviors, linguistics and motivators of the more visible racial and ethnic groups in the U.S. (Elmer, 1986, Ulmer, 2008). The cross-cultural mentoring experiences of Indo-Caribbeans in the U.S. are obscured from the research despite their rich socio-historic culture. The purpose of this phenomenological study was to explore the perceptions of Indo-Caribbean protégés regarding the effects of their cross-cultural mentoring experiences in the United States. Phenomenology is "the systematic attempt to uncover and describe...the internal meaning structures, of lived experience [by studying the] particulars or instances as they are encountered" (Van Manen, 1990, p. 10). Criterion and snowball sampling were used to recruit 15 participants. A semi-structured interview guide was used to gather data and Creswell's (2007) simplified version of Moustakas's (1994) Modification of the Stevick-Colaizzi-Keen Method of Analysis of Phenomenological Data was used to analyze the data. Three themes emerged: (a) "Sitting at the feet of gurus" taught protégés how to accept guidance, (b) Guru-Shishya: Learning and Discipleship, ways that protégés perceived mentors' guidance related to work, skill acquisition, and social or emotional support, and (c) Samavartan sanskar: Building Coherence, helped protégés understand, manage and find meaning. Protégés' goals and professional expectations determined what they wanted from cross-cultural mentoring relationships and what they were willing to endure within those relationships. Since participants valued achievement and continuous improvement, mentor support was integral to making meaning and developing a sense of coherence in their lives. Implications regarding cross-cultural mentoring relationships together with recommendations for future research conclude the study.

Living on both sides of the fence: A phenomenological study of human resource development professionals as downsizing survivors and strategic human resource development facilitators

This phenomenological study explored how HR professionals who identified themselves as facilitators of strategic HRD (SHRD) perceived the experience of being an organizational agent-downsizing survivor. Criterion and snowball sampling were used to recruit 15 participants for this study. A semi-structured interview guide was used to interview participants. Creswell's (2007) simplified version of Moustakas's (1994) Modification of the Stevick-Colaizzi-Keen Method of Analysis of Phenomenological Data was used to analyze the data. Four main themes and corresponding sub-themes emerged from an inductive data analysis. The four main themes were a) the emotionality of downsizing, b) feeling responsible, c) choice and control, and d) possibilities for growth. Participants perceived downsizing as an emotional organizational change event that required them to manage their own emotions while helping others do the same. They performed their roles within an organizational atmosphere that was perceived as chaotic and filled with apprehension, shock, and a sense of ongoing loss, sadness and grieving. They sometimes experienced guilt and doubt and felt deceptive for having to keep secrets from others when planning for downsizing. Participants felt a strong sense of responsibility to protect employees emotionally, balance employee and organizational interests, and try to ensure the best outcomes for both. Often being there for others meant that they put on their games faces and took care of themselves last. Participants spoke of the importance of choosing one's attitude, being proactive rather than reactive, and finding ways to regain control in the midst of organizational crisis. They also perceived that although downsizing was emotionally difficult to go through that it provided possibilities for self, employee, and organizational growth.

Results of analysis and model simulation of the bed profiles

Bedforms such as dunes and ripples are ubiquitous in rivers and coastal seas, and commonly described as triangular shapes from which height and length are calculated to estimate hydrodynamic and sediment dynamic parameters. Natural bedforms, however, present a far more complicated morphology; the difference between natural bedform shape and the often assumed triangular shape is usually neglected, and how this may affect the flow is unknown. This study investigates the shapes of natural bedforms and how they influence flow and shear stress, based on four datasets extracted from earlier studies on two rivers (the Rio Paraná in Argentina, and the Lower Rhine in The Netherlands). The most commonly occurring morphological elements are a sinusoidal stoss side made of one segment and a lee side made of two segments, a gently sloping upper lee side and a relatively steep (6 to 21°) slip face. A non-hydrostatic numerical model, set up using Delft3D, served to simulate the flow over fixed bedforms with various morphologies derived from the identified morphological elements. Both shear stress and turbulence increase with increasing slip face angle and are only marginally affected by the dimensions and positions of the upper and lower lee side. The average slip face angle determined from the bed profiles is 14°, over which there is no permanent flow separation. Shear stress and turbulence above natural bedforms are higher than above a flat bed but much lower than over the often assumed 30° lee side angle.

An automatic method of above-water iceberg 3-D profiling based on autonomous surface craft (ASC) using surface images and LIDAR

This thesis reports on a novel method to build a 3-D model of the above-water portion of icebergs using surface imaging. The goal is to work towards the automation of iceberg surveys, allowing an Autonomous Surface Craft (ASC) to acquire shape and size information. After collecting data and images, the core software algorithm is made up of three parts: occluding contour finding, volume intersection, and parameter estimation. A software module is designed that could be used on the ASC to perform automatic and fast processing of above-water surface image data to determine iceberg shape and size measurement and determination. The resolution of the method is calculated using data from the iceberg database of the Program of Energy Research and Development (PERD). The method was investigated using data from field trials conducted through the summer of 2014 by surveying 8 icebergs during 3 expeditions. The results were analyzed to determine iceberg characteristics. Limitations of this method are addressed including its accuracy. Surface imaging system and LIDAR system are developed to profile the above-water iceberg in 2015.

On the convergence of the method of successive averages for calculating user equilibrium in traffic networks

Peer reviewed

Factors associated with self-cutting as a method of self-harm: findings from the Irish National Registry of Deliberate Self-Harm

Background: Research suggests that patients presenting to hospital with self-cutting differ from those with intentional overdose in demographic and clinical characteristics. However, large-scale national studies comparing self-cutting patients with those using other self-harm methods are lacking. We aimed to compare hospital-treated self-cutting and intentional overdose, to examine the role of gender in moderating these differences, and examine the characteristics and outcomes of those patients presenting with combined self-cutting and overdose. Methods: Between 2003 and 2010, the Irish National Registry of Deliberate Self-Harm recorded 42,585 self-harm presentations to Irish hospital emergency departments meeting the study inclusion criteria. Data were obtained on demographic and clinical characteristics by independent data registration officers. Results: Compared with overdose only, involvement of self-cutting (with or without overdose) was significantly more common in males than females, with an overrepresentation of males aged <35 years. Independent of gender, involvement of self-cutting (with or without overdose) was significantly associated with younger age, city residence, repetition within 30 days and repetition within a year (females only). Factors associated with self-cutting as the sole method were no fixed abode/living in an institution, presenting outside 9 a.m. to 5 p.m., not consuming alcohol and repetition between 31 days and 1 year (males only). Conclusion: The demographic and clinical differences between self-harm patients underline the presence of different subgroups with implications for service provision and prevention of repeated self-harm. Given the relationship between self-cutting and subsequent repetition, service providers need to ensure that adequate follow-up arrangements and supports are in place for the patient.

Iterative reconstruction as a novel method of radiation dose reduction at computed tomography in patients with Crohn's disease

Prior work of our research group, that quantified the alarming levels of radiation dose to patients with Crohn’s disease from medical imaging and the notable shift towards CT imaging making these patients an at risk group, provided context for this work. CT delivers some of the highest doses of ionising radiation in diagnostic radiology. Once a medical imaging examination is deemed justified, there is an onus on the imaging team to endeavour to produce diagnostic quality CT images at the lowest possible radiation dose to that patient. The fundamental limitation with conventional CT raw data reconstruction was the inherent coupling of administered radiation dose with observed image noise – the lower the radiation dose, the noisier the image. The renaissance, rediscovery and refinement of iterative reconstruction removes this limitation allowing either an improvement in image quality without increasing radiation dose or maintenance of image quality at a lower radiation dose compared with traditional image reconstruction. This thesis is fundamentally an exercise in optimisation in clinical CT practice with the objectives of assessment of iterative reconstruction as a method for improvement of image quality in CT, exploration of the associated potential for radiation dose reduction, and development of a new split dose CT protocol with the aim of achieving and validating diagnostic quality submillisiever t CT imaging in patients with Crohn’s disease. In this study, we investigated the interplay of user-selected parameters on radiation dose and image quality in phantoms and cadavers, comparing traditional filtered back projection (FBP) with iterative reconstruction algorithms. This resulted in the development of an optimised, refined and appropriate split dose protocol for CT of the abdomen and pelvis in clinical patients with Crohn’s disease allowing contemporaneous acquisition of both modified and conventional dose CT studies. This novel algorithm was then applied to 50 patients with a suspected acute complication of known Crohn’s disease and the raw data reconstructed with FBP, adaptive statistical iterative reconstruction (ASiR) and model based iterative reconstruction (MBIR). Conventional dose CT images with FBP reconstruction were used as the reference standard with which the modified dose CT images were compared in terms of radiation dose, diagnostic findings and image quality indices. As there are multiple possible user-selected strengths of ASiR available, these were compared in terms of image quality to determine the optimal strength for this modified dose CT protocol. Modified dose CT images with MBIR were also compared with contemporaneous abdominal radiograph, where performed, in terms of diagnostic yield and radiation dose. Finally, attenuation measurements in organs, tissues, etc. with each reconstruction algorithm were compared to assess for preservation of tissue characterisation capabilities. In the phantom and cadaveric models, both forms of iterative reconstruction examined (ASiR and MBIR) were superior to FBP across a wide variety of imaging protocols, with MBIR superior to ASiR in all areas other than reconstruction speed. We established that ASiR appears to work to a target percentage noise reduction whilst MBIR works to a target residual level of absolute noise in the image. Modified dose CT images reconstructed with both ASiR and MBIR were non-inferior to conventional dose CT with FBP in terms of diagnostic findings, despite reduced subjective and objective indices of image quality. Mean dose reductions of 72.9-73.5% were achieved with the modified dose protocol with a mean effective dose of 1.26mSv. MBIR was again demonstrated superior to ASiR in terms of image quality. The overall optimal ASiR strength for the modified dose protocol used in this work is ASiR 80%, as this provides the most favourable balance of peak subjective image quality indices with less objective image noise than the corresponding conventional dose CT images reconstructed with FBP. Despite guidelines to the contrary, abdominal radiographs are still often used in the initial imaging of patients with a suspected complication of Crohn’s disease. We confirmed the superiority of modified dose CT with MBIR over abdominal radiographs at comparable doses in detection of Crohn’s disease and non-Crohn’s disease related findings. Finally, we demonstrated (in phantoms, cadavers and in vivo) that attenuation values do not change significantly across reconstruction algorithms meaning preserved tissue characterisation capabilities with iterative reconstruction. Both adaptive statistical and model based iterative reconstruction algorithms represent feasible methods of facilitating acquisition diagnostic quality CT images of the abdomen and pelvis in patients with Crohn’s disease at markedly reduced radiation doses. Our modified dose CT protocol allows dose savings of up to 73.5% compared with conventional dose CT, meaning submillisievert imaging is possible in many of these patients.