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Article
Publication date: 27 January 2022

Elana Jaffe, David Rosen, Aunchalee Palmquist and Andrea K. Knittel

This study aims to estimate the prevalence of individuals receiving hormone therapy for menopause management and the prevalence of underlying conditions that may constrain options…

100

Abstract

Purpose

This study aims to estimate the prevalence of individuals receiving hormone therapy for menopause management and the prevalence of underlying conditions that may constrain options for pharmacologic menopause management in the prison context.

Design/methodology/approach

This study reviewed all prescriptions dispensed by the North Carolina Department of Public Safety between July 1, 2015, and June 30, 2016, for relevance to menopause management. Relevant medications were those either recommended for menopause management or those indicated for management of conditions that may complicate menopause management, as per the 2015 clinical decision-support algorithm tool developed by the North American Menopause Society. Analysis was restricted to women between the ages of 45 and 75.

Findings

Of 1,120 women, a majority (77.8%) were between the ages of 45 and 54. Less than 5% of individuals in this study were prescribed estrogen-containing therapy. The most commonly prescribed medications that may constrain options for menopause treatment were related to hypertension and other cardiovascular disease or mental health conditions.

Research limitations/implications

The retrospective nature of this data set limits the findings, given that researchers did not have access to diagnoses or data on polypharmacy. Still, this study indicates that many women over 45 experiencing incarceration are living with health conditions that may complicate menopause symptom management with hormone therapy. Future research in carceral settings must examine the prevalence of menopause-related symptoms as well as access to and quality of comprehensive menopause management.

Originality/value

There is a paucity of literature around the menopause-related needs of individuals experiencing incarceration. To the best of the authors’ knowledge, no other research has examined prevalence of pharmacologic menopause management among women who are incarcerated.

Details

International Journal of Prisoner Health, vol. 18 no. 2
Type: Research Article
ISSN: 1744-9200

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Article
Publication date: 1 December 2001

Alok Kataria and David W. Rosen

Stereolithography apparatus (SLA) is capable of in situ fabrication of complex parts, as well as mechanisms and complex devices with embedded components. In this paper, a series…

1598

Abstract

Stereolithography apparatus (SLA) is capable of in situ fabrication of complex parts, as well as mechanisms and complex devices with embedded components. In this paper, a series of example devices are presented to illustrate the power of building around embedded components (inserts). The problem formulation, solution approach, and specific rules and procedures are presented using these examples and experimental results. A case study approach is used for presentation. These procedures and results lend insight into promising new applications of SLA technology, as well as novel methods of implementing additional functionality into SLA and other rapid prototyping technologies.

Details

Rapid Prototyping Journal, vol. 7 no. 5
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 18 April 2016

Xiayun Zhao and David W. Rosen

Exposure controlled projection lithography (ECPL) is an additive manufacturing process based on controlled UV photopolymerization. This paper aims to explore an advanced…

516

Abstract

Purpose

Exposure controlled projection lithography (ECPL) is an additive manufacturing process based on controlled UV photopolymerization. This paper aims to explore an advanced closed-loop control methodology to ECPL.

Design/methodology/approach

This paper proposes an evolutionary cycle to cycle (EC2C) control method, and started with a reduced order EC2C time control to control only the exposure time for given DMD bitmaps, which correspond to target 3D part cross-sections. A preliminary EC2C time control scheme was developed and followed by two types of EC2C time controllers based on two different parameter estimation methods, recursive least squares and L1 norm minimization (L1Min). Both algorithms were in an exponential weighted form, resulting in EWRLS and EWL1Min, to weight more on recent data to reflect the current process dynamics.

Findings

EWRLS was found to outperform EWL1Min in terms of computation speed and stability. The simulation study demonstrated that the proposed EC2C time control method was capable of adaptively tracking the ECPL process dynamics and updating online the model parameters with real-time measurements. It could control perfectly the exposure time for each bitmap, achieving the desired height for each layer and resulting in a total cured height conforming to the target 3D part height.

Research limitations/implications

The accuracy of EC2C time control method relies heavily on fast and accurate measurement, and this research assumes availability of an adequate real-time metrology. Measurement errors are not considered in this paper and will be explored in future. Only simulation study was performed without physical experiments to verify the EC2C controller.

Practical implications

For implementation, a real-time measurement system needs to be developed and the EC2C control software needs to be programmed and interfaced with the physical system.

Originality/value

It concludes that EC2C control method is very promising for a physical implementation, and could be extended for the development of a more comprehensive closed-loop controller for both exposure time and intensity to improve the ECPL process precision and robustness.

Details

Rapid Prototyping Journal, vol. 22 no. 3
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 15 June 2010

Jane Chu, Sarah Engelbrecht, Gregory Graf and David W. Rosen

The purpose of this paper is to investigate design synthesis methods for designing lattice cellular structures to achieve desired stiffnesses. More generally, to find appropriate…

2512

Abstract

Purpose

The purpose of this paper is to investigate design synthesis methods for designing lattice cellular structures to achieve desired stiffnesses. More generally, to find appropriate design problem formulations and solution algorithms for searching the large, complex design spaces associated with cellular structures.

Design/methodology/approach

Two optimization algorithms were tested: particle swarm optimization (PSO) and Levenburg‐Marquardt (LM), based on a least‐squares minimization formulation. Two example problems of limited complexity, specifically a two‐dimensional cantilever beam and a two‐dimensional simply‐supported plate, were investigated. Computational characteristics of the algorithms were reported for design problems with hundreds of variables. Constraints from additive manufacturing processes were incorporated to ensure that resulting designs are realizable.

Findings

Both PSO and LM succeeded in searching the design spaces and finding good designs. LM is one to two orders of magnitude more efficient for this class of problems.

Research limitations/implications

Three‐dimensional problems are not investigated in this paper.

Practical implications

LM appears to be a viable algorithm for optimizing structures of complex geometry for minimum weight and desired stiffness.

Originality/value

The testing of design synthesis methods (problem formulations and algorithms) for lattice cellular structures, and the testing of PSO and LM algorithms, are of particular value.

Details

Rapid Prototyping Journal, vol. 16 no. 4
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 25 July 2008

Sungshik Yim and David W. Rosen

The purpose of this paper is to present an information model (ontology) for design‐for‐manufacturing (DFM) problems, where parts are to be manufactured using an additive…

525

Abstract

Purpose

The purpose of this paper is to present an information model (ontology) for design‐for‐manufacturing (DFM) problems, where parts are to be manufactured using an additive manufacturing process. DFM problem formulation is often challenging since the formulation step requires both design and manufacturing process knowledge. The ontology also captures some relationships that model how that manufacturing knowledge applies to part designs. The ontology is implemented and serves as a repository of DFM problems that are available for reuse.

Design/methodology/approach

The ontology is encoded using a description logic (DL) known as ALE. Using this ontology, a designer can retrieve archived DFM problems that are similar to a problem being formulated. DLs are a subset of first‐order logic that have been used for information modeling in several application areas, including engineering information management. They are used typically to construct classification hierarchies that can be efficiently searched.

Findings

The paper demonstrates that the DL model is correct by showing that the classification hierarchies that are computed match our DFM ontology. Retrieval of DFM problems is demonstrated using a prototype implementation of our ontology. Examples are taken from the area of design for manufacture using the stereolithography process.

Research limitations/implications

The domain of the ontology is limited to additive manufacturing processes. Only DFM problems related to the determination of design parameters (e.g. dimensions) were within the scope of this work.

Originality/value

No ontology for DFM problems has been presented previously. Implementation of the ontology using DL is also original.

Details

Journal of Manufacturing Technology Management, vol. 19 no. 6
Type: Research Article
ISSN: 1741-038X

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Article
Publication date: 1 August 2008

Benay Sager and David W. Rosen

The purpose of this paper is to demonstrate that significant surface finish improvements can be accomplished in stereolithography (SL) fabricated parts by applying a new process…

1236

Abstract

Purpose

The purpose of this paper is to demonstrate that significant surface finish improvements can be accomplished in stereolithography (SL) fabricated parts by applying a new process planning method based on parameter estimation (PE).

Design/methodology/approach

PE is a method that finds a set of parameter values that minimize a measure of deviation. In this work, the measure of deviation is the difference between the exposure received by points along down‐facing surfaces and the SL resin's critical exposure.

Findings

The surface finish of down‐facing surfaces can be improved by a factor of 2‐9, depending upon the surface angle, compared with parts prepared using commercially available software. Surface finishes less than 1 μm Ra have been demonstrated on a SLA‐250/50 machine.

Research limitations/implications

Only down‐facing surfaces can have their surface finish improved using this method.

Practical implications

Common form errors known as “stair‐stepping” can be diminished on parts fabricated using SL.

Originality/value

The usage of PE methods for process planning is a new approach.

Details

Rapid Prototyping Journal, vol. 14 no. 4
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 9 February 2015

Amy M Gregory, H.G. Parsa, Khaldoon Nusair, David J Kwun and Sanjay Putrevu

This research aims to propose a model that may be used to classify product attributes according to their effect on customer satisfaction within the services industry. It also aims…

1789

Abstract

Purpose

This research aims to propose a model that may be used to classify product attributes according to their effect on customer satisfaction within the services industry. It also aims to apply the model to vacation ownership products and to explore attributes related to both the purchase and use of the product: an owned luxury product.

Design/methodology/approach

Data from 3,231 vacation ownership customers of multiple international companies were analyzed using a modified Kano model and related questionnaire.

Findings

This study reveals the effect that specific product attributes have on customer satisfaction. It addresses previously unexplored attributes (i.e. sales techniques and hotel program benefits), confirms others previously identified with customer satisfaction (i.e. amenities, exchange benefits, hotel affiliation and vacation counselors) and reveals those that had no incremental effect on overall satisfaction (i.e. financing and activities).

Practical implications

Results of this study suggest that attributes have varying effects on customers’ overall satisfaction and submit that companies may wish to focus their efforts in particular areas to maintain or improve overall satisfaction. Doing so may create opportunities for companies to increase satisfaction, operate more efficiently or distinguish themselves within the marketplace.

Originality/value

This research is the first comprehensive examination of customer satisfaction related to the purchase and consumption of an owned luxury vacation product, reveals misconceptions related to certain product attributes, uncovers previously unidentified attributes, provides a model for examining customer satisfaction that could be applied across lodging products and provides a benchmark for future studies.

Details

International Journal of Contemporary Hospitality Management, vol. 27 no. 1
Type: Research Article
ISSN: 0959-6119

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Article
Publication date: 1 August 2003

David W. Rosen, Yong Chen, Shiva Sambu, Janet K. Allen and Farrokh Mistree

A new design‐for‐manufacturing method, called the geometric tailoring (GT), and the associated digital interface concept have been developed that enable the design activities to…

1018

Abstract

A new design‐for‐manufacturing method, called the geometric tailoring (GT), and the associated digital interface concept have been developed that enable the design activities to be separated from the manufacturing activities. Conditions for the successful application of this method are investigated. The GT method is demonstrated for rapid prototyping and rapid tooling technologies, where prototype parts are required to match the production properties as closely as possible. This method is embodied in a system called the rapid tooling testbed (RTTB). Research work is presented on GT and the distributed computing environment underlying the RTTB. Examples are summarized from the usage of this method and testbed.

Details

Rapid Prototyping Journal, vol. 9 no. 3
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 30 November 2012

David Goldbloom and Louise Bradley

This paper aims to examine the progress of the Mental Health Commission of Canada (MHCC) over the first five years of its existence toward stated goals while existing outside the…

1336

Abstract

Purpose

This paper aims to examine the progress of the Mental Health Commission of Canada (MHCC) over the first five years of its existence toward stated goals while existing outside the constitutional framework of health care funding.

Design/methodology/approach

The paper is a review of the outputs of the MHCC with emphasis on its first‐ever mental health strategy for Canada, knowledge exchange network, anti‐stigma initiatives, randomized controlled trial of housing‐first initiatives for the homeless mentally ill, as well as other completed projects.

Findings

Consultation and collaboration are essential aspects of working successfully with people with lived experience of mental illness, their families, health professionals, and governments. At the same time, when expectations are high, needs are great, and opinions are varied, disappointment and frustration are inevitable.

Research limitations/implications

Although the MHCC initiatives include the largest single funded research project in mental health in Canadian history, and evaluation is built into other initiatives, the political dimension of its work does not lend itself to research evaluation.

Practical implications

The creation of an organization outside the constitutional framework of health care funding may allow for a catalytic role in precipitating change.

Social implications

The emphasis on anti‐stigma campaigns targeted at defined populations (youth, health professionals, workforce, journalists) may combat the discrimination people with mental illnesses and their families experience.

Originality/value

The paper shows that the Canadian experience is, to date, largely undescribed in the peer‐reviewed literature and may influence other jurisdictions. One of its interventions is already being replicated internationally.

Details

Mental Health Review Journal, vol. 17 no. 4
Type: Research Article
ISSN: 1361-9322

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Article
Publication date: 26 April 2011

Amit S. Jariwala, Fei Ding, Aparna Boddapati, Victor Breedveld, Martha A. Grover, Clifford L. Henderson and David W. Rosen

The purpose of this paper is to present a model that can be used to simulate the photopolymerization process in micro‐stereolithography (SL) in order to predict the shape of the…

1436

Abstract

Purpose

The purpose of this paper is to present a model that can be used to simulate the photopolymerization process in micro‐stereolithography (SL) in order to predict the shape of the cured parts. SL is an additive manufacturing process in which liquid photopolymer resin is cross‐linked and converted to solid with a UV laser light source. Traditional models of SL processes do not consider the complex chemical reactions and species transport occurring during photopolymerization and, hence, are incapable of accurately predicting resin curing behavior. The model presented in this paper attempts to bridge this knowledge gap.

Design/methodology/approach

The chemical reactions involved in the photopolymerization of acrylate‐based monomers were modeled as ordinary differential equations (ODE). This model incorporated the effect of oxygen inhibition and diffusion on the polymerization reaction. The model was simulated in COMSOL and verified with experiments conducted on a mask‐based micro‐SL system. Parametric studies were conducted to investigate the possibilities to improve the accuracy of the model for predicting the edge curvature.

Findings

The proposed model predicts well the effect of oxygen inhibition and diffusion on photopolymerization, and the model accurately predicts the cured part height when compared to experiments conducted on a mask‐based SL system. The simulated results also show the characteristic edge curvature as seen in experiments.

Research limitations/implications

A triacrylate monomer was used in the experiments conducted, so results may be limited to acrylate monomers. Shrinkage was not considered when comparing cured part shapes to those predicted using COMSOL.

Originality/value

This paper presents a unique and a pioneering approach towards modeling of the photopolymerization reaction in micro‐SL process. This research furthers the development of patent pending film micro‐SL process which can be used for fabrication of custom micro‐optical components.

Details

Rapid Prototyping Journal, vol. 17 no. 3
Type: Research Article
ISSN: 1355-2546

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