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1 – 10 of 42Z.‐M. Li, K.M. Dzurko and S.P. McAlister
We have developed a two‐dimensional model for quantum‐well lasers which solves, self‐consistently, the semiconductor equations together with the complex scalar wave equation and…
Abstract
We have developed a two‐dimensional model for quantum‐well lasers which solves, self‐consistently, the semiconductor equations together with the complex scalar wave equation and the photon rate equation. To predict the threshold current accurately we have included the wavelength‐ and position‐dependence of the gain and the spontaneous emission. For the complex wave equation successive over relaxation (SOR) is used with two adaptive acceleration parameters for the complex wave amplitude and for the eigenvalue. Since the rate equation near threshold can be driven into divergence during iteration for a steady state solution, we have introduced a special damping technique to overcome this problem. Our model enables us to predict the characteristics of a quantum‐well laser with a minimal number of empirical constants. The output of the model includes light‐current characteristics, and the current and optical field intensity distributions. We show the results of a calculation for a graded‐index separate‐confinement heterostructure single quantum‐well (GRIN‐SCH SQW) laser.
Carlos Alberto Ferreira Fernandes
The aim of this paper is to develop simulation tools for the analysis of modified structures of distributed feedback (DFB) laser diodes adequate for single longitudinal mode (SLM…
Abstract
Purpose
The aim of this paper is to develop simulation tools for the analysis of modified structures of distributed feedback (DFB) laser diodes adequate for single longitudinal mode (SLM) operation.
Design/methodology/approach
The paper uses matricial techniques: the transfer matrix method (TMM). When compared to the eigenvalue approach, the matricial techniques are more general and flexible and hence are especially adequate to deal with the analysis and structural design of DFB laser diodes. In this work, the author makes a general description of the TMM, enhancing its importance with some applications by considering the threshold and above‐threshold analysis of a modified DFB laser structure.
Findings
The increasing demands on laser performance, mainly in the area of optical communication systems, have lead to the fabrication of more‐and‐more complex structures. In viewing the development of the associated technology, the importance of the simulation tools revealed of crucial importance.
Originality/value
The simulation model used in this work has been described in other works of the author. In the present analysis a general description of the TMM was implemented, summarizing the results of previous studies for the threshold and above‐threshold regimes of modified DFB laser structures specially designed to show SLM operation.
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Pia Vedel Ankersen, Rikke Grynderup Steffensen, Emely Ek Blæhr and Kirsten Beedholm
Life expectancy is 15–20 years shorter for individuals with than for people without mental illness. Assuming that undiagnosed and undertreated somatic conditions are significant…
Abstract
Purpose
Life expectancy is 15–20 years shorter for individuals with than for people without mental illness. Assuming that undiagnosed and undertreated somatic conditions are significant causes, the Central Denmark Region set out to implement joint psychiatric and somatic emergency departments (EDs) to support integrated psychiatric/somatic care as an effort to prolong the lifetime of individuals with mental illness. Through the lens of Normalization Process Theory, the authors examine healthcare frontline staff’s perceptions of and work with the implementation of integrated psychiatric/somatic care in the first joint-specialty ED in Denmark.
Design/methodology/approach
A single-case mixed-methods study using Normalization Process Theory (NPT) as an analytic framework to evaluate implementation of psychiatric/somatic integrated care (IC) in a joint-specialty emergency department. Data were generated from observations, qualitative interviews and questionnaires distributed to the frontline staff.
Findings
Implementation was characterized by a diffuse normalization leading to an adaption of the IC in a fuzzy alignment with existing practice. Especially, confusion among the staff regarding how somatic examination in the ED would ensure prolonged lifetime for people with mental illness was a barrier to sense-making and development of coherence among the staff. The staff questioned the accuracy of IC in the ED even though they recognized the need for better somatic care for individuals with mental illness.
Practical implications
This study highlights that a focus on outcomes (prolonging lifetime for people with mental illness and reducing stigmatization) can be counterproductive. Replacing the outcome focus with an output focus, in terms of how to develop and implement psychiatric/somatic IC with the patient perspective at the center, would probably be more productive.
Originality/value
In 2020, the Danish Health Authorities published new whole-system recommendations for emergency medicine (EM) highlighting the need for intensifying integrated intra and interorganizational care including psychiatric/somatic IC (ref). Even though this study is not conclusive, it points to subjects that can help to identify resources needed to implement psychiatric/somatic IC and to pitfalls. The authors argue that the outcome focus, prolonging the lifetime for individuals with mental illness by identifying somatic illness, was counterproductive. In accordance with the recommendations of contemporary implementation studies, the authors recommend a shift in focus from outcome to output focus; how to develop and implement psychiatric/somatic IC.
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Describes the benefits of a low‐cost digital library server using an electronic mail interface. Suggests hardware and software configurations. Outlines a hypothetical budget and…
Abstract
Describes the benefits of a low‐cost digital library server using an electronic mail interface. Suggests hardware and software configurations. Outlines a hypothetical budget and cost analysis for the first year of operation. Recommends a possible upgrade path. Suggests a “486” computer and v.34 high speed modem. Discusses the reasons for preferring the Linux adaptation of UNIX for the platform for this application. Recommends mail transport agent and outlines mail server programs available. The bibliography includes all online and printed references necessary to obtain and configure the software discussed.
Kirsi Günther, Eeva Ekqvist and Katja Kuusisto
The focus of this article is in documentation in substance abuse inpatient rehabilitation. Our article scrutinizes how workers give accounts of the documentation in the inpatient…
Abstract
Purpose
The focus of this article is in documentation in substance abuse inpatient rehabilitation. Our article scrutinizes how workers give accounts of the documentation in the inpatient substance abuse rehabilitation unit and what kind of client information the workers record.
Design/methodology/approach
The study focuses on institutional interaction and practices. Our data consist of interviews with substance abuse rehabilitation professionals (N = 15). We analyzed the interviews using content analysis and the account concept in keeping with the ethnomethodological research tradition.
Findings
Study shows how workers account for the significance of documentation. Workers deemed documentation significant in four different ways: in gathering basic and rehabilitation information, in storing and transmitting information, as a tool for analysis and assessment and in supporting linguistic transparency in substance abuse rehabilitation. Workers justified the significance of documentation by the legal requirement to record information about clients. Documented information enables clear management of client information and supports substance abuse rehabilitation work in various ways. Documentation contains descriptions of the client’s situation and work performed. Additionally, documentation serves as a tool for communication among social care professional.
Originality/value
Thus the research show that documentation plays a significance part in the inpatient substance abuse rehabilitation and are connected to its institutional tasks and practices.
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Sian Dallimore, Katharine Christie and Maria Loades
Multidisciplinary team (MDT) clinical supervision is being used in many mental health services but at present has not received adequate attention by researchers in order to…
Abstract
Purpose
Multidisciplinary team (MDT) clinical supervision is being used in many mental health services but at present has not received adequate attention by researchers in order to generate evidence-based approaches. The purpose of this paper is to explore the utility and staff perspectives of an MDT model of clinical supervision in the form of a “Clinical Discussion Group” (CDG) on an acute inpatient mental health ward within the context of the current literature on the components of effective supervision in order to make recommendations for practice.
Design/methodology/approach
In total, 12 members of staff working on the ward were interviewed to gather their perspective on attendance, helpful aspects, outcomes, unhelpful aspects, and changes. Interview transcripts were analysed using thematic analysis.
Findings
In total, 11 themes were identified, three within “The Group and how it operates” (attendance, discussion topics and facilitation), five within “Impact and Usefulness” (valued by staff, understanding a case, emotional benefit, learning and working together as a team) and three within “Changes to the Group” (organisation, discussion topic and group outcomes).
Originality/value
This paper explores the benefits and challenges of a CDG from the perspective of the staff who attend. It presents some recommendations for good practice which should be of use to managers and supervisors who wish to use team supervision to improve patient outcomes and also makes suggestions for future research in this field.
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Much of the body of literature analysing the gig economy focuses on its exploitation of low-wage workers and its role in increasing precarious work. This chapter approaches the…
Abstract
Much of the body of literature analysing the gig economy focuses on its exploitation of low-wage workers and its role in increasing precarious work. This chapter approaches the topic from a different angle, focussing on the contribution of the gig economy to the declining power of the medical profession. As well as facilitating and promulgating contingent work in healthcare, the gig economy disaggregates medical work into isolated on-demand micro-tasks on digital platforms. This has implications for the status and power of the medical profession, the doctor–patient relationship, and inter-professional boundaries in healthcare. The mechanisms through which these dynamics unfold, as well as the inter-related factors that support the transformations in the allocation and content of medical work, are discussed. These include the implications of heightened transparency of medical work resulting from unbundling of jobs, commodification of medical professionals, and platform-based vulnerabilities such as rating systems that impact doctor–patient relationships. Closure theory is drawn on to illuminate the dynamics of the transformation in professional boundaries and the arising conflict that it entails for the healthcare workforce at different levels. The conflict is theorised as an insidious exercise of closure by allied health professionals on the remit of the medical profession, which challenges remuneration, authority, and other exclusionary benefits traditionally accrued to the medical profession.
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Adefemi Aka, Abubakar Danladi Isah, Chukwudum J. Eze and Owolabi Timileyin
Non-value adding activities or wastes in the lean term have been the major challenge of the construction industry. Numerous studies have been conducted to investigate how such…
Abstract
Purpose
Non-value adding activities or wastes in the lean term have been the major challenge of the construction industry. Numerous studies have been conducted to investigate how such wastes can be reduced so as to improve the performance of the construction industry. However, the aspect of bricks production process (BPP) has not been extensively covered. Therefore, the purpose of this paper is to investigate the application of lean manufacturing concepts in BPP with a view to identifying the various wastes in the practice, the causes of these wastes and how such wastes can be reduced.
Design/methodology/approach
Mixed methods research design was adopted by the researchers where literature review was first conducted to establish the fundamental theories and practice standards of lean manufacturing process. Thereafter, a phenomenological study was carried out in a Shelter Clay and Brick Factory located in Minna, Niger State, Nigeria. The data obtained in the phenomenological study were analyzed through content analysis. These data served as the basis for the validation survey that subsequently followed the phenomenological study.
Findings
The findings in the study show that poor or inadequate supervision is the main factor responsible for wastes such as excessive drying of bricks, overheating of bricks and re-glazing of bricks in Nigerian BPP.
Research limitations/implications
The study focused on the various wastes in Nigerian BPP. It also focused on the various lean tools/techniques that can be adopted to reduce the wastes. Aspects such as the percentage of the wastes and their cost implication on the factory were not covered during the study and could be further investigated by prospective researchers.
Practical implications
The study provides knowledge on how lean thinking can be adopted to reduce wastes in BPP. Such knowledge may be beneficial to the present and prospective bricks producers. This implies that the proposed framework in the study allows producers of bricks to identify gaps in their implementation efforts, focus attention on areas that may require improvements, and access the benefits of lean approach in their factory products. The proposed framework may also be beneficial to the academics.
Originality/value
This paper first gain originality in the study context to propose for a lean framework that can be adopted to reduce wastes in BPP. Furthermore, the paper has not been previously published and all the information obtained from other sources are duly referenced.
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