Search results

The purpose of this paper is to produce electric discharge machining (EDM) electrodes by using stereolithography (SLA) rapid prototyping technique and investigate the machining performance of these electrodes. In the experimental part of the study, the performance of solid copper and copper‐coated SLA (cc/SLA) electrodes are observed and compared.

The performance outputs such as material removal rate, machining depth, workpiece surface roughness and electrode front surface wear are used as metrics of comparison. The temperature measurements taken from the face of both solid copper and cc/SLA electrodes indicated that the heat build up during machining significantly accelerated the failure of cc/SLA electrodes.

The paper finds that circulating the cooling liquid inside the internal cooling channels formed with SLA technique, elongated the life of cc/SLA electrodes by dissipating the heat from the coating.

The Fluent Computational Fluid Dynamics (CFD) Software is used to numerically analyze various aspects of cooling of cc/SLA electrodes. The key findings of the study are presented in this paper.

The purpose of this paper is to discuss an adaptive SLA mechanism for service sharing in virtual environment, which can organize and govern QoS items in terms of service execution time, reliability, and availability, and provides a common understanding about services, responsibilities, priorities, guarantees and warranties-related virtual cooperative issues.

The management framework for SLA is introduced, based on which the whole process including SLA contract, adaptive SLA negotiation strategy, SLA deployment and SLA assessment are discussed, and the prototype is implemented in the cloud manufacturing platform.

A proposed SLA framework for service sharing in virtual environments is given; electronic contracts are designed in the framework for encapsulating measurable aspects of service level agreements so as to provide common understanding about the service; and an improved SLA negotiation strategy with three phases is presented for the dynamicity of the virtual services.

The paper presents a very useful adaptive SLA mechanism for service sharing in virtual environments that can be utilized in concurrent or future advanced manufacturing modes.

The purpose of this paper is to examine service level agreements (SLAs) in the retail industry and uses empirical data to draw conclusions on the relationships between SLA parameters and retailer financial performance.

Based on prior SLA theories, hypotheses about the impacts of SLA confidentiality, choice of chargeback mechanisms and chargeback penalty on retailer inventory turnover are tested.

Retailer inventory turnover could vary by the level of SLA confidentiality, and the variation of retailer inventory turnovers could be explained by chargeback penalty.

The research findings may not be readily applicable to SLAs outside of the retail industry. Also, most conclusions were drawn from publicly available SLAs.

The significant relationships between SLA parameters and retailer inventory turnover imply that a retailer could improve its financial performance by leveraging its SLA design.

Not only does this study contribute to the understanding of retail SLA design in practice, but it also extends prior theories by investigating the implications of SLA design on the retailer inventory turnover.

The authors began this review of the research available on the topic of managing corporate libraries with the hypothesis that there has been a lack of funding for such research that in turn has limited its production. After reviewing the relevant research literature produced in the last three decades, however, the assumption of inadequate funding causing a lack of research on this topic could not totally be supported. As we sought to identify what funding was available, the literature suggested additional questions: How or if research on the subject of managing corporate libraries was encouraged and funded and by whom? What type of research would be most useful for corporate library managers? Finally, how research results were disseminated and whether the results had been put to use by practitioners? Here the authors are defining the topic of “managing libraries” in the broadest sense and occasionally delve more specifically into the topic of valuing library services. While we address corporate libraries in particular, most of our findings and commentary can be applied to special libraries in general.

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.

To report on the SLA Annual Conference held in June 2006 in Baltimore MD.

Provides a review of some of the events of the conference.

The annual conference aims to provide attendees continuing professional education, vendor presentations, invited papers and social events. Exhibits from library vendors include technology, information materials and services.

A conference report of interest to information professionals in academia, corporate and governmental information centers and libraries.

Mask projection micro‐stereolithography (MPμSLA) is an additive manufacturing process capable for fabricating true three‐dimensional microparts and hence, holds promise as a potential 3D MEMS fabrication process. With only a few MPμSLA systems developed and studied so far, the research in this field is inchoate and experimental in nature. In order to employ the MPμSLA technology for microfabrication, it is necessary to model its part building process and formulate a process planning method to cure dimensionally accurate microparts. The purpose of this paper is to formulate a process planning method for curing dimensionally accurate layers.

A MPμSLA system is designed and assembled. The process of curing a single layer in resin using this system is modeled as the layer cure model. The layer cure model is validated by curing test layers. This model is used to formulate a process planning method to cure dimensionally accurate layers. The process planning method is tested by conducting a case study.

The layer cure model is found to be valid within 3 percent for most of the features and within 10 percent for very small features (<250μm). The paper shows that ray tracing can be effectively used to model the process of irradiation of the resin surface in a MPμSLA system.

The process planning method is applicable only to those imaging systems, which are aberration limited as opposed to diffraction limited. The dimensional errors in the lateral dimensions of single layers cured by MPμSLA have been modeled, but not the vertical errors in 3D parts.

In this paper, a process planning method for MPμSLA has been presented for the first time.

The aim of this paper is to present the key areas of activity to be used for drafting service level agreements (SLAs) for electronic services and, at the same time, to present best practices and problems that arise from the application of this discipline.

A range of recently published (2000‐2005) works has been reviewed, in order to: a) analyse how an SLA has to be defined and applied b) identify the applicable best practices and c) identify the problem areas.

Provides guidance for the business and the Application Service Provider (ASP) when they want to engage in an outsourcing agreement by presenting best practices and problems that occur from the application of SLAs.

Suggests further research is needed in a number of research areas such as: development of semantic models for SLAs, development of flexible pricing models in relation with SLAs, definition of SLAs in cases of dynamic service creation, etc.

A useful source of information both for academia and the business.

Provides practical insight on a specialized topic and guidance to researchers.

Internet services are being deployed over an infrastructure that involves co‐operation between multiple organizations and systems. This has necessitated the need for standard means to share the information between the service providers and their customers. This information essentially pertains to the service level obligations between the service provider and their customers so that the customers can ensure the quality of service (QoS) that they are able to achieve at their end. A service level agreement (SLA) essentially quantifies the level of service as it includes the metrics that define the quality of service. The research undertaken identifies the QoS dimensions, which are required to define the multimedia services. Each application used by the user will involve different values of the QoS dimensions in order to maintain an expected level of service. The QoS requirement for a particular application will also depend upon the provisioning of the network resources depending on the client and server side CPU and memory available for processing. The relationship between the system resources, QoS dimensions and the SLA has been depicted in the form of a general model of SLA and as an example taken for the video conferencing application.

Liquid crystal display (LCD)-based stereolithography (SLA) technique has been used in drug delivery and fabrication of microfluidic devices and piezoelectric materials. It is an additive manufacturing technique where an LCD source has been used as a mask to project the image onto the tank filled with photo curable resin. This resin, when interacted with light, becomes solid. However, critical information regarding the energy absorption during the compression analysis of different components three-dimensional (3D) printed by SLA process is still limited. Therefore, this study aims to investigate the effect of different process parameters on the compressive properties.

In the present study, the influence of layer thickness, infill density and build orientation on the compression properties is investigated. Four infill densities, that is, 20%, 40%, 60% and 80%; five-layer thicknesses, that is, 50 µm, 75 µm, 100 µm, 150 µm and 200 µm; and two different orientations, that is, YXZ and ZXY, have been selected for this study.

It is observed that the samples printed with acrylonitrile butadiene styrene (ABS) absorbed higher energy than the flexible polyurethane (FPU). Higher infill density and sample oriented on ZXY absorbed higher energy than sample printed on YXZ orientation, in both the ABS and FPU materials. Parts printed with 80% infill density and 200 µm layer thickness resulted into maximum energy for both the materials.

In this study, two different types of materials are used for the compression analysis using LCD-SLA-based 3D printer. Specific energy absorbed by the samples during compression testing is measured to compare the influence of parameters. The investigation of infill parameters particularly the infill density is very limited for the SLA-based 3D printing process. Also, the results of this study provide a database to select the print parameters to obtain the required properties. The results also compare the specific energy for hard and flexible material for the same combination of the process parameters.