bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reinventing production quality on a nano‐granularity level
Authors: Chun‐Fong Chiao Tina , Nayan Agarwal Kamal , Ma Kuang‐Fu , Chi Albert Y. 
Published: May 2009

PurposeThis paper aims to resolve the phenomenon of the gaps between plentiful data and useful information for many manufacturing companies.Design/methodology/approachBy introducing Bayesian dynamic sampling processes, a quality process control cycle will be achieved through the sequential linkages between the involved entities; namely, user's requirement statement, target specification document, database management, and data collection.FindingsFor commercial product‐development processes, the requirement for continuous product improvement can be done by adopting a Bayesian sequential procedure. As such, industry practitioners can be able to justify whether the manufactured products have been done successfully in fulfilling target specification documents on the nano‐scale granularity level. The unsatisfactory manufacturing cases may indicate the situations of the necessity for remedy treatments of component‐wise re‐engineering processes incrementally, or for radical innovation of creating new markets through new functional capacity, based on new technical generation of the target system.Originality/valueThis paper proposes managerial quality strategic decision guidelines which may be served as an incentive for stimulating further practical industrial case studies, especially on the area of quality products assurance.
Kaizen strategy and the drive for competitiveness: challenges and opportunities
Authors: Al Smadi Sami 
Published: May 2009

PurposeThe purpose of this paper is to revisit the Japanese model of continuous improvement (Kaizen) in order to evaluate its contribution to competitiveness in organizations and also recommend possible future research directions.Design/methodology/approachThis is a conceptual paper, and secondary databased. The paper examines a vast body of research, which looked at the model from different perspectives, and critically explores its potential benefits and drawbacks in organizations.FindingsThe paper concludes that, if properly implemented, Kaizen model can substantially contribute to continuous improvement and, thus, drive organizations for high competitiveness without a need for major investment.Practical implicationsThe findings suggest that the implementation of Kaizen calls for a development of a suitable culture within an organization that encourages creativity and promotes the theme of never settling on a status quo.Originality/valueThis paper shows that success of Kaizen model is not always guaranteed, as work environment and organizational culture can be the important variables in its implementation.
A look at outsourcing offshore
Authors: Bahrami Bahman 
Published: May 2009

PurposeMost debates concerning outsourcing offshore in recent years have been politically oriented and based on casual observations. The purpose of this paper is to provide a clear economic understanding of the subject and to present offshoring in the context of globalization and in a more integrated world economy.Design/methodology/approachThis paper is designed in a coherent way to provide the reader with an overview, scope, benefits, and costs of outsourcing offshore and suggest some appropriate policies to navigate in a globally interdependent and competitive environment.FindingsOutsourcing offshore is largely irreversible and the USA or other countries must invest heavily in ways to boost domestic workers' productivity and to manage workers' transitions to more competitive employment. This paper also provides evidence that, in the long run, outsourcing offshore is beneficial for the economy as a whole.Originality/valueThis paper delineates that outsourcing offshore is consistent with the theory of comparative advantage and value maximizing objectives of firms. It also provides insights for politicians and casual observers about critical aspects of outsourcing offshore.
Biomodeling of club foot deformity of babies
Authors: Jain Manak , Dhande Sanjay , Vyas Nalinaksh 
Published: May 2009

PurposeCongenital telipes equinovarus (CTEV) or club foot is a historical foot deformity where the foot is turned in and pointing down causing the subject to walk on the outside edges of foot. The non‐surgical correction of this deformity is an unsolved challenging problem in the medical domain and it becomes interesting due to the increasing number of such patients. The purpose of this paper is to build a biomodel of this historical foot deformity in newborn babies and hence an attempt to develop a corrective procedure using rapid prototyping (RP).Design/methodology/approachBiomodeling is a new technology that allows medical scan data sets to generate solid plastic replicas of anatomical structures. The medical scan data sets of live club foot baby patients were acquired and after image processing, biomodels of four live unilateral club foot baby patients are developed in a fused deposition modeling RP system.FindingsThe paper shows the location and position of abnormal bones and abnormal tarsal joints and is useful for management of club foot deformity in newborn babies. On visual study, it is observed that the talus is underdeveloped, talar neck is shorter and deviated in the medial and planter direction.Research limitations/implicationsThe major outcome of this paper is the detailed geometrical visualization of talus bone of club foot and normal foot that assists in diagnosis and better treatment of CTEV. In future, the developed biomodels of club foot help to develop a corrective device that assists in bringing the club to normal foot geometrys.Practical implicationsThese developed biomodels of club foot help in deciding the best corrective procedure for surgeons. The geometrical comparison between normal and club foot helps in developing a non‐surgical corrective procedure of this historical foot deformity. A 3D representation of talus bone provides an opportunity to view talus and analyse the ankle joint geometry that develops a favorable condition for diagnosis and treatment of this deformity.Originality/valueThe first time developed biomodels of clubfeet helps orthopaedic surgeons in preoperative surgical planning and consequently in carrying out biomechanical studies of club foot. The presented research plays a major role in planning a non‐surgical corrective procedure of this historical deformity. It also provides a platform for finite element analysis of club foot.
Effects of injection molding parameters on shrinkage and weight of plastic part produced by DMLS mold
Authors: Nagahanumaiah  , Ravi B. 
Published: May 2009

PurposeThe purpose of this paper is to present the results of an investigation into the effect of injection molding process parameters on the performance of direct metal laser sintered (DMLS) mold in producing quality Zytel nylon 66 plastic parts with consistency in part shrinkage and shot/part weight.Design/methodology/approachThe injection mold for an industrial component (hub gear) was fabricated in EOS M‐250 machine using bronze‐based material. The effect of four injection molding parameters (injection pressure, melt temperature, speed, and injection time) on part shrinkage and weight were studied experimentally using L9 orthogonal array. The weight of the part just after ejecting from the cavity, and the average shrinkage measured after cooling, were used in grey relational analysis technique to assess the effect of each molding parameter. Further, surface properties such as surface finish, wear, scratch and corrosion resistance tests were conducted on DMLS mold material samples, in order to evaluate its use in rapid manufacturing applications.FindingsThe study found that injection speed and melt temperature have significant influence on part weight and shrinkage. The optimized molding process variables were slightly more in the case of DMLS molds as compared with the parameters suggested in the plastic datasheet. Scanning electro microscope (SEM) analysis of the mold surface after producing 5,000 glass filled Nylon 66 (Zytel) moldings did not indicate any surface degradation, confirming the use of DMLS mold in rapid manufacturing of few thousands of moldings.Research limitations/implicationsThe grey relational analysis does not compute the effect of any two or more variables together unlike ANNOVA. Second, this study alone is not enough to estimate life of DMLS mold, although 5,000 glass filled nylon 66 moldings are successfully produced without any damage on mold surface.Practical implicationsThis investigation demonstrates a generic approach of using grey relational analysis to quantify the effect of different molding process variables on selected quality parameters. This method can be easily extended for new processes and materials. The preliminary tests on surface finish, scratch, wear and corrosion resistance performed on DMLS mold samples have highlighted the need for improving surface properties to enhance their life. The authors are currently working on hard coating of DMLS molds as one of the solutions.Originality/valueUse of grey relational analysis is new to the problem of injection molding process optimization. Moreover, effect of injection molding parameters on part weight and shrinkage in DMLS mold has not been studied previously. This study helps while considering DMLS molds for manufacturing few thousands of parts.
Piezo‐electric head application in a new 3D printing design
Authors: Rahmati Sadegh , Shirazi S.F. , Baghayeri H. 
Published: May 2009

PurposeThis paper aims to focus on redesigning a 3D printing machine, using piezoelectric demand‐mode technology head in order to improve the factors of accuracy, surface finishing and color quality of fabricated models.Design/methodology/approachThe work first identifies two kinds of ink‐jet printing heads, and then develops a new design of 3D printing machine, based on piezoelectric head technology. Fabricated models by this new 3D printing machine were compared with the same models fabricated by current 3D printing machines (z406).FindingsThe comparison between the constructed models by two types of 3D printing machines shows improvement factors of accuracy, surface finishing and color quality using piezoelectric head in the current 3D printing machine.Research limitations/implicationsIn order to provide a colorful binder, a type of binder such as ZB56 was combined with six different colors of ink namely black, cyan, magenta, yellow, light cyan, and light magenta.Practical implicationsThe new designed and manufactured 3D printing machine provides the ability to construct more accurate models with improved quality.Originality/valueApart from the above practical implications, this work provides an accurate tool for injection of the live cells into vital textures in order to create bones, members and dentures without any chemical or physical changes in cells.
Recycling of polyamide 12 based powders in the laser sintering process
Authors: Dotchev Krassimir , Yusoff Wan 
Published: May 2009

PurposeThe purpose of this paper is to investigate the polyamide 12 (PA12) powder properties deterioration in the laser sintering (LS) process and propose a methodology for more efficient powder recycling. The main goals are: to recommend a level of input PA2200 powder properties which could guarantee acceptable part quality in the LS process; and selection of the refresh rate in order to minimise the consumption of fresh material.Design/methodology/approachThe paper analyses the LS processing conditions and current recycling practices in relation to the deterioration or ageing of the PA12‐based powders. Samples of new and recycled grades of PA2200 powder were artificially aged in a temperature‐controlled oven and then tested using melt flow rate (MFR) indexer. Also, un‐sintered powder samples collected from different locations within various builds, and different LS machines (EOSINT P700 and Sinterstation® 2500 HiQ) were tested.FindingsThe powder exposed at higher temperature and longer time experiences a much higher deterioration rate. The temperature and the time at which the un‐sintered material was exposed are the most influential parameters for the powder aging. It was confirmed that the MFR index is a very sensitive indicator of the changes in the powder properties and provides a relatively fast and inexpensive method of measuring the rate of the powder degradation because of the LS process. The powder located in the periphery and the top of a build has a higher MFR and therefore is less deteriorated. In contrast, powder located in the centre, or in the bottom of a long build has much lower MFR and therefore is less usable.Practical implicationsBased on the findings, a methodology for powder recycling is proposed. It allows a better control of the input material properties, a consistent quality of the fabricated parts, and more efficient use of the LS material.Originality/valueThe paper provides some useful information for the properties deterioration of PA12‐based powders (PA2200) in relation to the temperature and time at which the material is exposed in the LS.
Construction of 3D biological matrices using rapid prototyping technology
Authors: Maher P.S. , Keatch R.P. , Donnelly K. , Mackay R.E. , Paxton J.Z. 
Published: May 2009

PurposeHydrogels with low viscosities tend to be difficult to use in constructing tissue engineering (TE) scaffolds used to replace or restore damaged tissue, due to the length of time it takes for final gelation to take place resulting in the scaffolds collapsing due to their mechanical instability. However, recent advances in rapid prototyping have allowed for a new technology called bioplotting to be developed, which aims to circumvent these inherent problems. This paper aims to present details of the process.Design/methodology/approachThe paper demonstrates how by using the bioplotting technique complex 3D geometrical scaffolds with accurate feature sizes and good pore definition can be fabriated for use as biological matrices. PEG gels containing the cell‐adhesive RGD peptide sequence were patterned using this method to produce layers of directional microchannels which have a functionalised bioactive surface. Seeding these gels with C2C12 myoblasts showed that the cells responded to the topographical features and aligned themselves along the direction of the channels.FindingsThis process allows plotting of various materials into a media bath containing material of similar rheological properties which can be used to both support the structure as it is dispensed and also to initiate cross‐linking of the hydrogel. By controlling concentrations, viscosity and the temperature of both the plotting material and the plotting media, the speed of the hydrogel gelation can be enhanced whilst it is cross‐linking in the media bath. TE scaffolds have been produced using a variety of materials including poly(ethylene glycol) (PEG), gelatin, alginic acid and agarose at various concentrations and viscosities.Originality/valueThis paper describes one of the very few examples of accurate construction of 3D biological microporous matrices using hydrogel material fabricated by the bioplotting technique. This demonstrates that this technique can be used to produce 3D scaffolds which promote tissue regeneration.
CAD‐CAM‐RTV – lost‐wax casting technology for medical implants
Authors: Manuel de A. Monteiro Ramos António , António Simões José 
Published: May 2009

PurposeThe purpose of this paper is to present the development of a technical procedure for the manufacturing of medical implant prototypes.Design/methodology/approachThe paper was performed on a new hip implant design and manufactured with different metallic alloys F75 (ASTM) commonly used in biomedical applications. Dimensional parameters between the computer‐aided design (CAD) geometry and the prototypes and surface roughness for different casting alloy were compared. A CAD model was used for machining of a prototype. Room temperature vulcanising (RTV) rubber moulds allowed the manufacturing of wax models of the femoral prosthesis. A specific lost‐wax casting (LWC) technology was used to manufacture prototypes for in vitro tests. The final geometry was dimensionally controlled using different type of parameters (performance, average, standard, maximum and minimum deviations), surface roughness (Ra, Rt and Rp) were measured for all prototypes.FindingsTo obtain a small number of implants, RTV rubber vacuum casting technique can be used to obtain lost wax models with good dimensional stability. No significant dimensional differences were observed relatively to the virtual model. However, the temperature of the wax and the rubber mould were important parameters to obtain good quality wax models. Surface roughness was different for different alloys.Practical implicationsThe design and development of a new hip femoral prosthesis prototype based on rapid tooling techniques to manufacture LWC prototypes is suitable for clinical trials.Originality/valueThis paper describes a biomanufacturing methodology to manufacture biomedical implant prototypes.
The evolution of rapid prototyping in dentistry: a review
Authors: Azari Abbas , Nikzad Sakineh 
Published: May 2009

PurposeThe goal of rapid mechanical prototyping is to be able to quickly fabricate complex‐shaped, 3D parts directly from computer‐aided design models. The key idea of this novel technology is based upon decomposition of 3D computer models data into thin cross‐sectional layers, followed by physically forming the layers and stacking them up; “layer by layer technique.” This new method of modeling has raised many attentions in dentistry especially in the field of surgery and implantology. The purpose of this review study is to represent the historical development and various methods currently used for building dental appliances. It is also aimed to show the many benefits which can be achieved by using this new technology in various branches of dentistry.Design/methodology/approachThe major existing resources, including unpublished data on the internet, were considered.FindingsAlthough, creating 3D objects in a layered fashion is an idea almost as old as human civilization but, this technology has only recently been employed to build 3D complex models in dentistry. It seems that in near future many other methods will develop which could change traditional dental practices. It is advisable to include more unit hours in dental curriculums to acquaint dental students with the many benefits of this novel technology.Originality/valueIt is hard to believe that the routine dental techniques were affected by revolutionary concepts originally theorized by engineering methods. It is a reality that in future, most of the restorative disciplines will be fully revised and the computer methods be evolved to an extent where dentistry can be performed by computer‐assisted methods with optimum safety, simplicity, and reliability.
Toward a unifying framework to support informal learning theory, research and practice
Authors: Marsick Victoria J. 
Published: May 2009

PurposeThe purpose of this Guest Editorial is to introduce the papers in this special issue and outline how they help us to better understand the theory and practice of informal learning.Design/methodology/approachThe Guest Editorial provides an overview of the topics discussed in the special issue, focusing on teachers and schools, social workers, and knowledge management in academic and business settings.FindingsIn practice informal and formal learning are often inextricably intertwined.Originality/valueThe papers in this issue contribute to the search for a unifying framework to support theory, research and practice.
Experienced teachers' informal workplace learning and perceptions of workplace conditions
Authors: Hoekstra Annemarieke , Korthagen Fred , Brekelmans Mieke , Beijaard Douwe , Imants Jeroen 
Published: May 2009

PurposeThe purpose of this paper is to explore in detail how teachers' perceptions of workplace conditions for learning are related to their informal workplace learning activities and learning outcomes.Design/methodology/approachFrom a sample of 32 teachers, a purposeful sampling technique of maximal variation was used to select two cases described in this paper. In a mixed methods design quantitative data are used to position the two teachers in relation to their peers. Qualitative data are used to describe the two cases in depth.FindingsThe findings show how the diverging ways in which the two teachers perceive and actively shape their workplace conditions help to explain differences in the teachers' learning activities and learning outcomes.Originality/valueScholars have argued that informal workplace learning is embedded in interdependent practices that arise from the interaction between social practices and individual agency. The case studies provide insight into how workplace conditions for learning are shaped in this interaction and how perceptions of these conditions enable or constrain teachers' informal workplace learning.
Teachers' workplace learning within informal contexts of school cultures in the United States and Lithuania
Authors: Jurasaite‐Harbison Elena 
Published: May 2009

PurposeThe purpose of this paper is to explore informal contexts of teachers' workplace professional learning and inform educational researchers, teacher educators, administrators and teachers about ways in which teachers learn to improve their practice. By questioning how teachers learn on‐the‐job to be better teachers and how school cultures position them as learners, this study seeks to generates hypotheses about relationships between the nature of workplace professional learning and its content and informal contexts.Design/methodology/approachAn ethnographic design based on a grounded theory generates analytic categories from interviews, participants' reflective journals and field notes through comparison of learning environments in three contrasting schools in two countries – Lithuania and the USA. Discourse analysis is employed to analyze three cases of the schools' informal learning contexts in order to better understand how teachers learned through everyday interactions.FindingsWithin each case, the findings illuminate three facets of school culture that provide or fail to provide opportunities for teacher learning in informal contexts: school leadership, teachers' professional relationships, and their individual stances as learners.Research limitations/implicationsThe limitations of the paper derive from its focus on school cultures as learning organizations producing detailed thick descriptions, which are culturally specific and may not necessarily be transferable to other schools.Practical implicationsThe implications underline that teachers and teacher educators could enhance teachers' professional learning by contributing to building and sustaining the opportunities necessary to maintain professional growth at teachers' workplaces.Originality/valueThe value of the paper is in: defining specific cultural features in schools that create or fail to create opportunities for teachers to learn informally; showing how teachers use these opportunities for their learning; calling for re‐evaluation of professional development systems to include informal learning as an important path for professional growth.