bluuebunny/crossref_metadata_2025 huggingface dataset:
In vivohost-pathogen interaction as revealed by global proteomic profiling of zebrafish larvae
Authors: Díaz-Pascual Francisco , Ortíz-Severín Javiera , Varas Macarena A. , Allende Miguel L. , Chávez Francisco P.
Published: May 2017

The outcome of a host-pathogen interaction is determined by the conditions of the host, the pathogen, and the environment. Although numerous proteomic studies ofin vitro-grownmicrobial pathogens have been performed,in vivoproteomic approaches are still rare. In addition, increasing evidence supports thatin vitrostudies inadequately reflectin vivoconditions. Choosing the proper host is essential to detect the expression of proteins from the pathogeninvivo. Numerous studies have demonstrated the suitability of zebrafish (Danio rerio) embryos as a model toin vivostudies ofPseudomonas aeruginosainfection. In most zebrafish-pathogen studies, infection is achieved by microinjection of bacteria into the larvae. However, few reports using static immersion of bacterial pathogens have been published. In this study we infected 3 days post-fertilization (DPF) zebrafish larvae withP. aeruginosaPAO1 by immersion and injection and tracked thein vivoimmune response by the zebrafish. Additionally, by using non-isotopic (Q-exactive) metaproteomics we simultaneously evaluated the proteomic response of the pathogen (P. aeruginosaPAO1) and the host (zebrafish). We found some zebrafish metabolic pathways, such as hypoxia response via HIF activation pathway, exclusively enriched in the larvae exposed by static immersion. In contrast, we found that inflammation mediated by chemokine and cytokine signaling pathways was exclusively enriched in the larvae exposed by injection, while the integrin signaling pathway and angiogenesis were solely enriched in the larvae exposed by immersion. We also found important virulence factors fromP. aeruginosathat were enriched only after exposure by injection, such as the Type-III secretion system and flagella-associated proteins. On the other hand,P. aeruginosaproteins involved in processes like biofilm formation, cellular responses to antibiotic and starvation were enriched exclusively after an exposure by immersion.

We demonstrated the suitability of zebrafish embryos as a model forin vivohost-pathogen based proteomic studies inP. aeruginosa. Our global proteomic profiling identifies novel molecular signatures that give systematic insight into zebrafish-Pseudomonasinteraction.
Making sense of dementia
Authors: Harland Juliet , Bath Peter A. , Wainwright Ann , Seymour Jeremy
Published: May 2017

Purpose

The purpose of this paper is to investigate the information behaviours of patients newly diagnosed with dementia.

Design/methodology/approach

This is a cross-sectional qualitative study, using in-depth interviews with 13 people recently diagnosed with dementia.

Findings

Reactions to a diagnosis of dementia varied and these influenced the perception of the value of information when making sense of the diagnosis. Information was avoided if participants did not feel that they could influence their situation; instead, participants relied on internal explanations to normalise their memory loss. Barriers to information seeking and use included not knowing who to speak to, perceived stigma associated with dementia and difficulty of applying generic information to own situation. Some participants valued information that confirmed their suspicions and provided explanations.

Research limitations/implications

This study was based on a small sample size (n=13), the findings may not be generalisable to all people with dementia; however, the findings may be transferable to people who have recently been diagnosed with dementia.

Practical implications

There is not a one-size-fits-all approach to information provision for people with dementia at diagnosis, information should be tailored to individuals.

Social implications

There is a need to address the feeling of powerlessness and futility that some people with dementia experience at diagnosis, as this precludes independent information seeking and use. People receiving a diagnosis may need additional support and information pertinent to their specific circumstances, separate from the information needs of their carer(s).

Originality/value

The study provides a new understanding of the information behaviours of people recently diagnosed with dementia and how these differ from those of informal carers.
An integrated model highlighting information literacy and knowledge formation in information behaviour
Authors: Ibenne Samuel Kelechukwu , Simeonova Boyka , Harrison Janet , Hepworth Mark
Published: May 2017

Purpose

The purpose of this paper is to review key models of people’s information behaviour (IB) exploring the integration of the concepts of information literacy (IL) and knowledge in their designs. Scholarly perspectives portray IL as providing individuals with capacity for good information practices that result in generating new knowledge. It is surprising that this important perspective is not reflected in the reviewed IB models. This paper contributes to the literature base by proposing a new model highlighting IL and knowledge as important concepts within the IB discourse.

Design/methodology/approach

A discourse of the integration of IL and knowledge, which are integral factors, associated with IB, in selected IB models.

Findings

Identifying a need for information and understanding its context is an IL attribute. IL underpins IB in providing awareness of information sources; how to search and use information appropriately for solving information needs and leveraging generated new knowledge. The generation of new knowledge results from using information, in a process that combines with sense-making and adaption. Correspondingly, the knowledge that develops, increases capability for sense-making and adaptation of information to suit various contexts of need, iteratively.

Originality/value

A new model of IB; the causative and outcome factors of information behaviour (COFIB) is proposed. COFIB stresses that IL and knowledge are prominent factors within the general framework of people’s IB. The model emphasises knowledge generation as the outcome of IB, applied in solving problems within specific contexts.
Mobile phones for development
Authors: Cibangu Sylvain K. , Hepworth Mark , Champion Donna
Published: May 2017

Purpose

This paper relayed an important line of Mark Hepworth’s work, which engages with information technologies and development. The purpose of this paper is to suggest a subfield of library and information science (LIS) for development to reclaim the role of information services and systems for social change in rural areas. The paper looked at the extent of development gained with the advent of mobile phones.

Design/methodology/approach

Rather than undertaking traditional large-scale, quantitative, context-independent and survey-type research, the paper employed capability approach and semi-structured interviews to ascertain the experiences that mobile phone kiosk vendors in the rural Congo had of mobile phones.

Findings

It was found that mobile phones should be geared towards the liberation, and not utilization or commodification of humans and their needs and that mobile phones were not a catalyst of human basic capabilities.

Research limitations/implications

Since the method employed is an in-depth qualitative analysis of mobile phone kiosk vendors, obtained results can be used to enrich or inform mobile phone experiences in other settings and groups.

Practical implications

This paper provided empirical evidence as to how an important group of mobile phone users could harness development with their mobiles.

Originality/value

Most LIS literature has presented mobile phones along the lines of information freedom or access, mass subscription, adoption rates, technological and entrepreneurial innovation, micro-credits, etc. However, the paper placed the topic development at the heart of LIS debates.
Myths about HIV and AIDS among serodiscordant couples in Malawi
Authors: Wella Kondwani , Webber Sheila , Levy Philippa
Published: May 2017

Purpose

The purpose of this paper is to report on research that uncovered myths about HIV and AIDS held by serodiscordant couples in Malawi, and the sources of these myths. The paper reflects on how the myths affect serodiscordant couples’ engagement with HIV and AIDS information.

Design/methodology/approach

Van Manen’s (1997) approach to analysis of phenomenological data was used to analyse data from in-depth interviews conducted in Malawi with 21 serodiscordant couples and three individuals who had separated from their partners because of serodiscordance.

Findings

Serodiscordant couples in Malawi believe and hold on to some inaccurate HIV and AIDS information that can be seen as “myths”. Some of these myths are perpetuated by official HIV and AIDS information when it is translated into the local languages. Other myths derive from social norms of the societies where the couples live.

Practical implications

The findings of this paper have practical implications for how HIV and AIDS information providers should engage with target audiences to understand the origins of the myths they hold. The findings also imply that some myths have technical, religious, moral and cultural bases which need to be addressed before challenging the myth itself.

Originality/value

Using real-life descriptions of experiences of HIV and AIDS information provided by serodiscordant couples, the authors reveal how myths can affect engagement with the information. The authors make recommendations on how to address myths in ways that contribute to a positive experience of HIV and AIDS information by serodiscordant couples.
The (mis)use of social media to communicate CSR in hospitality
Authors: Zizka Laura
Published: May 2017

Purpose

This paper aims to discuss how the hospitality industry is communicating corporate social responsibility (CSR) to its stakeholders, the premise being CSR communication through social media platforms will increase stakeholder engagement.

Design/methodology/approach

This paper is developed based on Schwartz and Carroll’s three-domain approach to CSR motivation, stakeholder theory and a synthesis of previous literature of CSR communication in the hospitality industry.

Findings

Successful communication through social media is based on two-way participative dialogue. Companies, especially the hospitality industry, have used social media to communicate information through social media in a one-way direction, that of giving information. One example is the communication of CSR actions and intentions as found on hospitality websites, intranets and social media platforms. While previous studies have shown a link between CSR communication through social media and corporate reputation, few studies have examined CSR communication through social media and its effects on specific stakeholder groups.

Research limitations/implications

Rather than assuming that CSR communication can be done successfully through a “one-size-fits-all” social media discourse, this paper suggests the need for specific messages and potentially different communication channels to increase engagement from each of the various stakeholders in the hospitality industry.

Originality/value

This is one of the first papers which tries to address how one communication channel, social media, can affect CSR communication and increase stakeholder engagement in the hospitality industry. This paper provides discussion on the usefulness of social media to communicate CSR messages and posits the need for future research projects on a macro and micro level.
Social media advertising in a competitive market
Authors: Thornhill Mike , Xie Karen , Lee Young Jin
Published: May 2017

Purpose

Previous literature has discussed the importance of two types of social media exposures: owned social media (OSM) exposures generated by service providers and earned social media (ESM) exposures initiated by consumers. This study aims to examine the relative effects of owned and ESM exposures on brand purchase, as well as their advertising externality to competing brands. Rooted in theory of planned behavior and advertising externality literature, this study hypothesizes that owned and ESM exposures positively influence brand purchase. Such effects, however, can spill over to competing brands that invest in social media marketing and co-exist in the market.

Design/methodology/approach

This study collects brand purchase records and social media messages on the Facebook brand pages of a group of service providers over 12 months. The data are assembled for time series analysis with the unit of analysis being “brand × bi-week”.

Findings

Using a blend of fixed-effects models and seemingly unrelated regressions, this study finds that both owned and ESM exposures positively affect brand purchase, the purchase effect of OSM exposures is greater than ESM exposures, OSM exposures generate not only more purchase of the focal brand but also positive advertising externality to competing brands, whereas ESM exposures locks up the advertising effect to the focal brand without spilling over to competing brands.

Originality/value

This study advances the understanding about the externality of social media exposures in an increasingly competitive market where multiple brands invest in social media marketing and co-exist. Important implications on the strategic use of social media exposures to drive brand purchase while competing with similar brands are provided.
What do we know about social media and firms’ financial outcomes so far?
Authors: Kizildag Murat , Altin Mehmet , Ozdemir Ozgur , Demirer Ilhan
Published: May 2017

Purpose

This paper aims to understand the emergence, the revolution and the relevant knowledge of academic research concentrating on social media (SM) and hospitality and tourism firms’ financial performance. The authors not only identified the gaps and critical issues in research but also re-conceptualized profound directions for the future research in technology and finance in the hospitality and tourism field.

Design/methodology/approach

This study adopted an in-depth review analysis to investigate and review previous scholarly papers published in hospitality, tourism and hospitality and tourism journals from January 2011 to the present. The authors thoroughly analyzed and reviewed peer-reviewed/refereed, blind-reviewed, full-length published articles and working papers within SM and hospitality firms’ financial performance. Editor notes, prefaces, research notes, industry articles, internet publications, conference preceding, books and book chapters were excluded.

Findings

Having examined the empirical content of 26 peer-reviewed scholarly articles, the authors clearly observed that none of the papers went beyond analyzing the effect of SM on hotels’ revenue per available room, revenues, net profit, average daily rate, occupancy rates, net operating income, etc., and all papers ignored the analysis of many critical financial proxies.

Research limitations/implications

This critique and review paper is limited to the relationship between SM and firms’ financial performance within the hospitality and tourism context.

Practical implications

This review provides a blueprint to guide future research, facilitate knowledge accumulation and create a new understanding and awareness in practice as well as SM and financial performance research.

Social implications

This paper complements and adds to previous work by demonstrating various aspects, evidences, findings and inferences regarding the association between online SM platforms and firms’ financial performance and by proposing rigorous abstract and specific future extensions to both practice and discipline-specific knowledge.

Originality/value

There is an absence of the most updated review study of published papers on SM and hospitality and tourism firms’ financial performance. Although how SM contributes to firms’ financial performance is clear to academicians and industry professionals, no solid consensus or theoretical certainty about what the authors know and do not know has been achieved.
The effectiveness of a sensory modulation workshop on health professional learning
Authors: Azuela Gilbert , Robertson Linda
Published: May 2017

Purpose

Workshops are commonly used to up-skill staff and their usefulness can be determined by measuring whether or not learning needs have been met and, in particular, whether attitudes have changed. In the field of mental health, sensory modulation workshops have been introduced to educate staff about preventative measures that reduce the use of seclusion and restraint for service users with challenging behaviours. The purpose of this paper is to evaluate the impact of such a workshop.

Design/methodology/approach

A one-day workshop was developed based on a review of the literature and feedback from previous workshops, and with input from an industry-based reference group. An evaluation tool was designed to measure the learning outcomes, i.e., the knowledge, skills, and attitudes of the 23 participants. The Statistical Package for the Social Sciences (SPSS v20) was used to analyse the data. Multi-variate analysis of variance was used to determine the relationship between variables.

Findings

A significant increase in the knowledge, skills, and attitudes of mental health staff was identified after the one-day workshop (F=106.346, df=1, p<0.000). When considering which participants showed most benefits, it was shown that the demographics had no effect, i.e., education level, practice discipline, years of work experience in mental health, and previous sensory modulation training.

Practical implications

Measuring learning outcomes provides essential information about whether or not the learning objectives have been met. This allows future workshops to be tailored to ensure that the learning opportunity is at the correct level for the learners. More traditional evaluations that elicit the views of the content covered and teaching methods should additionally be used to supplement this information.

Originality/value

Workshops are often evaluated on the basis of the participants’ subjective response to a quick questionnaire. Developing a tool to measure outcomes is a more effective way to determine what has been learned and to ensure that positive outcomes for individuals and their organisations can be reached.
Human capital analytics: why are we not there?
Authors: Boudreau John , Cascio Wayne
Published: May 2017

Purpose

While human capital analytics (HCA) recently has developed enormous interest, most organizations still find themselves struggling to move from operational reporting to analytics. The purpose of this paper is to explore why that is the case and can be done to change that.

Design/methodology/approach

Referring to the “LAMP” model, the authors stress four elements as potential reasons why HCA are not sufficiently being “pushed” toward their audience, namely, logic, analytics, measures, and process. Similarly, they name five conditions why the wider use of HCA is not “pulled” in by the analytics user.

Findings

The authors investigations show that these “push” and “pull” factors behind the lack of greater use of HCA represent fertile ground for future research and implications for practitioners on both ends.

Practical implications

These “push” and “pull” factors behind the lack of greater use of HCA represent fertile ground for future research and implications for practitioners on both ends.

Originality/value

These “push” and “pull” factors behind the lack of greater use of HCA represent fertile ground for future research and implications for practitioners on both ends.
Human capital analytics: too much data and analysis, not enough models and business insights
Authors: Levenson Alec , Fink Alexis
Published: May 2017

Purpose

The purpose of this paper is to address the barriers to the rapid development of effective HR analytics capabilities in organizations.

Design/methodology/approach

Literature and conceptual review of the current state of HR analytics.

Findings

“HR analytics” is used to refer to a too-wide array of measurement and analytical approaches, making strategic focus difficult. There is a misconception that doing more measurement of HR activities and human capital will necessarily lead to actionable insights. There is too much focus on incremental improvement of existing HR processes, detracting from diagnosing the problems with business performance. Too much time is spent on mining existing data, to the detriment of model building and testing, including collecting new more appropriate data. Too much energy is consumed with basic tasks of data management. Stakeholders avoid action by nitpicking the details of the data.

Practical implications

Practitioners who follow the guidance provided should find that their application of HR analytics leads to more relevant and actionable insights.

Social implications

More effective application of HR analytics should lead to better decision making in organizations and more effective resource allocation.

Originality/value

A new look at the field of HR analytics that synthesizes the research literature and current practice in organizations.
An ideal hospital
Authors: Chandrasiri Singithi (Sidney)
Published: May 2017

Purpose

The purpose of this paper is to explore a novel overarching strategy in tackling the key issues raised by the recent inquiry into bullying, harassment and discrimination in surgical practice and surgical training in Australian and New Zealand hospitals.

Design/methodology/approach

The approach taken is an analysis of the available evidence-based literature to inform the proposed viewpoint. The theoretical subject scope presented is a discussion of how and why the various strategies put forward in this paper should be integrated into and led from an overarching workforce engagement platform.

Findings

The key themes isolated from the Inquiry into Australian and New Zealand surgical practice ranged from abuse of power by those in leadership positions, gender inequity in the surgical workforce, opaque and corrupt complaints handling processes, excessive surgical trainee working hours to bystander silence secondary to a fear of reprisal. A workforce engagement perspective has elicited the potential to counter various impacts, that of clinical ineffectiveness, substandard quality and safety, inefficient medical workforce management outcomes, adverse economic implications and the operational profitability of a hospital. Generic strategies grounded in evidence-based literature were able to then be aligned with specific action areas to provide a new leadership framework for addressing these impacts.

Originality/value

To the author’s knowledge, this is one of the first responses providing a framework on how medical managers and hospital executives can begin to lead a comprehensive and practical strategy for changing the existing culture of bullying, harassment and discrimination in surgical practice by using a staff engagement framework.
An evaluation of a leadership development coaching and mentoring programme
Authors: Le Comte Lyndsay , McClelland Beverley
Published: May 2017

Purpose

The purpose of this paper was to determine the value and impact of the Leadership Development – Coaching and Mentoring Programme at Counties Manukau Health and understand how the skills gained are applied.

Design/methodology/approach

Mixed-methods approach including surveys of programme participants and senior staff and semi-structured interviews with programme participants.

Findings

The survey response rate was 24.4 per cent for programme participants and 30 per cent for senior staff. Eight programme participants participated in semi-structured interviews. Of the 70 programme participants, 69 utilised their learning from the programme; 45 of 70 changed their approach to managing staff; and 40 of 68 programme participants reported that meeting with peers for triad group coaching was the most challenging aspect of the programme. Key themes identified through interviews included: working with others; not owning others’ problems; professional support and development; coaching and mentoring; future participants.

Practical implications

The majority of participants changed their leadership behaviours as a result of the programme, which has resulted in improved communication, a more supportive culture and distributed leadership. These changes contribute to better patient care.

Originality value

There is a paucity of evidence in the literature about the impact of coaching and mentoring programme on leadership development and how the skills gained in such programmes are applied in practice in a healthcare context. This evaluation helps to address that gap.
Leading nurses: emotional intelligence and leadership development effectiveness
Authors: Crowne Kerri Anne , Young Thomas M. , Goldman Beryl , Patterson Barbara , Krouse Anne M. , Proenca Jose
Published: May 2017

Purpose

The purpose of this paper is to examine the effectiveness of an emotional intelligence (EI) and leadership development education program involving 20 nurse leaders at nursing homes. Also, it investigates the relationship between EI and transformational leadership.

Design/methodology/approach

Three research questions are posed. Correlation analysis and t-tests were conducted to answer the questions posed.

Findings

The findings of this paper indicate that the EI educational development was effective, while the personal leadership development was not. The data also showed a positive significant relationship between EI and transformational leadership.

Research limitations/implications

This paper is limited by the small sample size; thus, a causal relationship between EI and leadership could not be investigated. Additionally, the sample was not randomly selected because of the commitment needed from the participants. Furthermore, the paper was focused on nurse leaders in nursing homes, so it may not be generalizable to other populations.

Practical implications

With the increasing need for nursing home facilities and the limited training generally provided to nurses who move into managerial roles in these facilities, it is critical for organizations to understand the effectiveness of educational programs that exist. Moreover, the findings of this paper may provide information that would be useful to others who wish to develop EI and/or leadership education for nurses.

Originality/value

While much research exists on EI and transformational leadership, little of this research focuses on nurses in nursing home facilities. Thus, this paper fills a gap in the literature.
Edge quality in fused deposition modeling: II. experimental verification
Authors: Armillotta Antonio , Bianchi Stefano , Cavallaro Marco , Minnella Stefania
Published: May 2017

Purpose

This paper aims to provide an experimental evaluation of geometric errors on the edges of parts manufactured by the fused deposition modeling (FDM) process.

Design/methodology/approach

An experimental plan was conducted by building parts in ABS thermoplastic resin on a commercially available machine with given combinations of the three geometric variables (inclination, included and incidence angle) defined in the first part of the paper. Edges on built parts were inspected on a two-dimensional non-contact profilometer to measure position and form errors.

Findings

The analysis of measurement results revealed that the edge-related variables have significant influences on the geometric errors. The interpretation of error variations with respect to the different angles confirmed the actual occurrence of the previously discussed error causes. As an additional result, quantitative predictions of the errors were provided as a function of angle values.

Research limitations/implications

The experimental results refer to fixed process settings (material, FDM machine, layer thickness, build parameters, scan strategies).

Originality/value

The two-part paper is apparently the first to have studied the edges of additively manufactured parts with respect to geometric accuracy, a widely studied topic for surface features.
Sequential additive manufacturing: automatic manipulation of 3D printed parts
Authors: Aroca Rafael Vidal , Ventura Carlos E.H. , De Mello Igor , Pazelli Tatiana F.P.A.T.
Published: May 2017

Purpose

This paper aims to present a monitoring system and the usage of a robotic arm to remove finished parts of a three-dimensional (3D) printer build plate, enabling 3D printers to continuously build a sequence of parts.

Design/methodology/approach

The system relies on a 2-degree of freedom planar manipulator. The moment to remove printed parts from the printer build plate can be determined based on direct communication with the 3D printer control software or using information from a computer vision system that applies background subtraction and Speeded up Robust Features methods.

Findings

The proposed system automatically detects the end of standard 3D print jobs and controls the robotic arm to remove the part.

Research limitations/implications

Lighting variation can deteriorate the response of the computer vision system, which can be minimized using a controlled illumination environment. In addition, the printer build plate edges must be free so the parts can slip off the printer build plate when the robot pushes them out.

Practical implications

The system enables a more practical and automatized usage of 3D printers, reducing the need of human operators.

Social implications

The proposed system can reduce work hours of laboratory personnel, as there is no need to remove the printed parts manually before another job starts.

Originality/value

Computer vision system monitors the printing process and the automation system that enables continuous sequential 3D printing of parts. A prototype is described, which can be easily replicated with low cost parts.
Experimental characterization of the mechanical properties of 3D-printed ABS and polycarbonate parts
Authors: Cantrell Jason T. , Rohde Sean , Damiani David , Gurnani Rishi , DiSandro Luke , Anton Josh , Young Andie , Jerez Alex , Steinbach Douglas , Kroese Calvin , Ifju Peter G.
Published: May 2017

Purpose

This paper aims to present the methodology and results of the experimental characterization of three-dimensional (3D) printed acrylonitrile butadiene styrene (ABS) and polycarbonate (PC) parts utilizing digital image correlation (DIC).

Design/methodology/approach

Tensile and shear characterizations of ABS and PC 3D-printed parts were performed to determine the extent of anisotropy present in 3D-printed materials. Specimens were printed with varying raster ([+45/−45], [+30/−60], [+15/−75] and [0/90]) and build orientations (flat, on-edge and up-right) to determine the directional properties of the materials. Tensile and Iosipescu shear specimens were printed and loaded in a universal testing machine utilizing two-dimensional (2D) DIC to measure strain. The Poisson’s ratio, Young’s modulus, offset yield strength, tensile strength at yield, elongation at break, tensile stress at break and strain energy density were gathered for each tensile orientation combination. Shear modulus, offset yield strength and shear strength at yield values were collected for each shear combination.

Findings

Results indicated that raster and build orientations had negligible effects on the Young’s modulus or Poisson’s ratio in ABS tensile specimens. Shear modulus and shear offset yield strength varied by up to 33 per cent in ABS specimens, signifying that tensile properties are not indicative of shear properties. Raster orientation in the flat build samples reveals anisotropic behavior in PC specimens as the moduli and strengths varied by up to 20 per cent. Similar variations were observed in shear for PC. Changing the build orientation of PC specimens appeared to reveal a similar magnitude of variation in material properties.

Originality/value

This article tests tensile and shear specimens utilizing DIC, which has not been employed previously with 3D-printed specimens. The extensive shear testing conducted in this paper has not been previously attempted, and the results indicate the need for shear testing to understand the 3D-printed material behavior fully.
Efficient design optimization of variable-density cellular structures for additive manufacturing: theory and experimental validation
Authors: Cheng Lin , Zhang Pu , Biyikli Emre , Bai Jiaxi , Robbins Joshua , To Albert
Published: May 2017

Purpose

The purpose of the paper is to propose a homogenization-based topology optimization method to optimize the design of variable-density cellular structure, in order to achieve lightweight design and overcome some of the manufacturability issues in additive manufacturing.

Design/methodology/approach

First, homogenization is performed to capture the effective mechanical properties of cellular structures through the scaling law as a function their relative density. Second, the scaling law is used directly in the topology optimization algorithm to compute the optimal density distribution for the part being optimized. Third, a new technique is presented to reconstruct the computer-aided design (CAD) model of the optimal variable-density cellular structure. The proposed method is validated by comparing the results obtained through homogenized model, full-scale simulation and experimentally testing the optimized parts after being additive manufactured.

Findings

The test examples demonstrate that the homogenization-based method is efficient, accurate and is able to produce manufacturable designs.

Originality/value

The optimized designs in our examples also show significant increase in stiffness and strength when compared to the original designs with identical overall weight.
Improvement of FDM parts’ surface quality using optimized neural networks – medical case studies
Authors: Vahabli Ebrahim , Rahmati Sadegh
Published: May 2017

Purpose

To improve the quality of the additive manufacturing (AM) products, it is necessary to estimate surface roughness distribution in advance. Although surface roughness estimation has been previously studied, factors leading to the creation of a rough surface and a comprehensive test for model validation have not been adequately investigated. Therefore, this paper aims to establish a robust model using empirical data based on optimized artificial neural networks (ANNs) to estimate the surface roughness distribution in fused deposition modelling parts. Accordingly, process parameters such as time, cost and quality should be optimized in the process planning stage.

Design/methodology/approach

Process parameters were selected via a literature review of surface roughness estimation modelling by analytical and empirical methods, and then a specific test part was fabricated to provide a complete evaluation of the proposed model. The ANN structure was optimized by trial and error method and evolutionary algorithms. A novel methodology based on the combination of the intelligent algorithms including the ANN, linked to the particle swarm optimization (PSO) and imperialist competitive algorithm (ICA), was developed. The PSOICA algorithm was implemented to increase the capability of the ANN to perform much faster and converge more precisely to favorable results. The performances of the ANN models were compared to the most well-known analytical models at build angle intervals of equal size. The most effective process variable was found by sensitivity analysis. The validity of proposed model was studied comprehensively where different truncheon parts and medical case studies including molar tooth, skull, femur and a custom-made hip stem were built.

Findings

This paper presents several improvements in surface roughness distribution modelling including a more suitable method for process parameter selection according to the design criteria and improvements in the overall surface roughness of parts as compared to analytical methods. The optimized ANN based on the proposed advanced algorithm (PSOICA) represents precise estimation and faster convergence. The validity assessment confirms that the proposed methodology performs better in varied conditions and complex shapes.

Originality/value

This research fills an important gap in surface roughness distribution estimation modelling by using a test part designed for that purpose and optimized ANN models which uses purely empirical data. The novel PSOICA combination enhances the ability of the ANN to perform more accurately and quickly. The advantage in using actual surface roughness values is that all factors resulting in the creation of a rough surface are included, which is impossible if other methods are used.
Investigation of separation force for constrained-surface stereolithography process from mechanics perspective
Authors: Ye Hang , Venketeswaran Abhishek , Das Sonjoy , Zhou Chi
Published: May 2017

Purpose

One of the major concerns of the constrained-surface stereolithography (SLA) process is that the built-up part may break because of the force resulting from the pulling-up process. This resultant force may become significant if the interface mechanism between the two contact surfaces (i.e. newly cured layer and the bottom of the resin vat) produces a strong bonding between them. The purpose of this paper is to characterize the separation process between the cured part and the resin vat by adopting an appropriate and simple mechanics-based model that can be used to probe the pulling-up process.

Design/methodology/approach

In this paper, the time-histories of the pulling-up forces are measured using FlexiForce® force sensors. The experimental data are analyzed and used to estimate the constitutive parameters of the separation mechanism. Here, the separation mechanism is modeled based on the concept of cohesive zone model (CZM) that is well-studied in the field of fracture mechanics. By using the experimentally measured pulling-up force, this paper proposes a very efficient inverse technique to estimate the constitutive parameters for the CZM. The constitutive laws for the CZM facilitate in relating the separation force at the interface between the cured part and the resin vat in terms of the pulling-up velocity. Unlike work proposed earlier, computationally expensive full-scale finite element runs are not essential in the current work while estimating the required parameters of the constitutive laws. Instead, mechanics-based computationally efficient surrogate model is proposed to readily estimate these constitutive parameters.

Findings

Two constitutive laws are compared on the basis of their predictions of the separation force profile. Excellent match is obtained between the measured and the predicted separation force profiles.

Originality/value

This paper selects a suitable mechanics-based model that can characterize the separation process and proposes a computationally efficient scheme to estimate the required constitutive parameters. The proposed scheme can be used to reliably predict the separation force for the constrained-surface SLA process, leading to improved productivity and reliability of the SLA processes in fabricating the built-up parts.
Synthesis and properties of modified PBT for FDM
Authors: Cao Shiqing , Yu Dandan , Xue Weilan , Zeng Zuoxiang , Zhu Wanyu
Published: May 2017

Purpose

The purpose of this paper is to prepare a new modified polybutylene terephalate (MPBT) for fused deposition modeling (FDM) to increase the variety of materials compatible with printing. And the printing materials can be used to print components with a complex structure and functional mechanical parts.

Design/methodology/approach

The MPBT, poly(butylene terephalate-co-isophthalate-co-sebacate) (PBTIS), was prepared for FDM by direct esterification and subsequent polycondensation using terephthalic acid (PTA), isophthalic acid (PIA), sebacic acid (SA) and 1,4-butanediol (BDO). The effects of the content of PIA (20-40 mol%) on the mechanical properties of PBTIS were investigated when the mole per cent of SA (αSA) is zero. The effects of αSA(0-7mol%) on the thermal, rheological and mechanical properties of PBTIS were investigated atnPTA/nPIA= 7/3. A desktop wire drawing and extruding machine was used to fabricate the filaments, whose printability and anisotropy were tested by three-dimensional (3D) printing experiments.

Findings

A candidate content of PIA introducing into PBT was obtained to be about 30 per cent, and the Izod notched impact strength of PBTIS increased with the increase of αSA. The results showed that the PBTIS (nPTA/nPIA= 7/3, αSA= 3-5mol%) is suitable for FDM.

Originality/value

New printing materials with good Izod notched impact strength were obtained by introducing PIA and SA (nPTA/nPIA= 7/3, αSA= 3-5 mol%) into PBT and their anisotropy are better than that of ABS.
Institutions and entrepreneurship: the mediating role of corruption
Authors: Mohammadi Khyareh Mohsen
Published: May 2017

Purpose

The purpose of this paper is to examine the mediating role of corruption in the relationship between entrepreneurship and institutional quality in a sample of 90 countries from all around the world.

Design/methodology/approach

The data were collected from the Global Entrepreneurship Monitor, which developed a model where Corruption Perception Index as a proxy for corruption mediates the relationship between the variable rule of law as a proxy for institutional quality and opportunity entrepreneurship as a proxy for productive entrepreneurship. Correlation, Baron and Kenny approach (causal steps approach) and PROCESS Macro (normal test theory) developed by Hayes were used to find out the direct and indirect effects of institutional quality between corruption and entrepreneurship.

Findings

The bootstrap mediation results indicated that institutional quality was a significant predictor of corruption and corruption was a significant predictor of entrepreneurship. These findings support the mediation hypothesis. In addition, findings showed that there is a negative relation between corruption and productive entrepreneurship and a positive relation between institutional quality and productive entrepreneurship.

Research limitations/implications

The current study only considered the single proxy for institutional quality, i.e. rule of law; therefore, some other proxies for institutional quality such as government effectiveness and doing business can be used for future studies. Moreover, the proposed model does not control for the country differences like GDP or development stages of countries.

Practical implications

The findings of this study indicate that the total association between institutional quality and entrepreneurship is not only direct but also that rule of law contributes to levels of entrepreneurship through reduced levels of corruption. As a result, countries with higher levels of rule of law tended to experience corruption at lower levels, which in turn contributed to the emergence of increased levels of entrepreneurship. Furthermore, these results may be beneficial for organizations fighting against corruption, because entrepreneurial activity can be add to the group of economical drivers constrained by corruption. It is also beneficial for policy makers who focus on promoting entrepreneurship, since one way to increase entrepreneurial activity is to lower the existing corruption level.

Originality/value

The results indicated that the direct effect of institutional quality on the entrepreneurship remained significant when controlling for corruption, thus suggesting partial mediation. In other words, corruption only mediates part of the effect of institutional quality on entrepreneurship, that is, the intervention (institutional quality) has some residual direct effect even after the mediator (corruption) was introduced into the model.
Competitive strategies, market orientation types and innovation strategies: finding the strategic fit
Authors: Kaliappen Narentheren , Hilman Haim
Published: May 2017

Purpose

The purpose of this paper is to review the strategic fit of competitive strategies, market orientation types and innovation strategies.

Design/methodology/approach

The paper is prepared by reviewing the relevant literatures on competitive strategies, market orientation types and innovation strategies as well as comparing and contrasting the common characteristics to attain fit.

Findings

The paper presents the criteria for distinguishing the different types of competitive strategies, market orientations and innovation strategies, along with a framework that fits a particular type of competitive strategy, market orientation and innovation strategy.

Practical implications

The paper provides an action framework based on characteristics of the competitive strategies (business strategy) along with the benefits of adopting a particular market orientation type and innovation strategy (functional strategies). This will facilitate the managers to execute appropriate competitive strategy that could well align with appropriate market orientation and innovation strategy.

Originality/value

This brief paper presents an original framework, with significant practical applications in a concise manner. The framework will provide a guide to the hotel top management in shaping and fitting an appropriate competitive strategies, market orientation types and innovation strategies.
Investigating the Effect of Fuel Rate Variation in an Industrial Thermal Cracking Furnace With Alternative Arrangement of Wall Burners Using Computational Fluid Dynamics Simulation
Authors: Mohammad Ghasemi Hossein , Gilani Neda , Towfighi Daryan Jafar
Published: May 2017

A new arrangement of side-wall burners of an industrial furnace was studied by three-dimensional computational fluid dynamics (CFD) simulation. This simulation was conducted on ten calculation domain. Finite rate/eddy dissipation model was used as a combustion model. Discrete ordinate model (DOM) was considered as radiation model. Furthermore, weighted sum of gray gas model (WSGGM) was used to calculate radiative gas properties. Tube skin temperature and heat flux profiles were obtained by solving mass, momentum, and energy equations. Moreover, fuel rate variation was considered as an effective parameter. A base flow rate of fuel (m˙=0.0695kg/s) was assigned and different ratios (0.25 m˙, 0.5 m˙, 2 m˙, and 4 m˙) were assigned to investigate the heat distribution over the furnace. Resulted temperature and heat profiles were obtained in nonuniform mode using the proposed wall burner arrangement. According to the results, despite increased heat transfer coefficient of about 34% for m˙–4 m˙, temperature profile for this rate is too high and is harmful for tube metallurgy. Also, the proper range for fuel rate variation was determined as 0.5–2 m˙. In this range, heat transfer coefficient and Nusselt number for m˙–2 m˙ were increased by 21% and for m˙–0.25 m˙ were decreased by about 28%.