A Generic System for Homogenous SLS Steel Materials

A generic approach to a variety if different steel materials for SLS based application has been examined. This approach is based on a base steel alloy powder mixed with a powder blend of much smaller particles. The powder blend is designed to both provide the highest possible density in the powder mass and melting material components for liquid phase sintering to full density. Furthermore, the liquid phase components in the powder blend are composed to both serve as a metallic binder for the green bodies and maintain the possibility to completely dissolve into the base material, forming a homogenous alloy. A powder blend with stainless steel base material was composed and tested and taken through the different process steps. While the formation of green bodies had limited success, to a large extent due to limitations in the process equipment, the sintering and diffusion behaviour showed promising results, both in respect to acquired densities, and homogeneity of the material.Mechanical Engineerin

Material Issues of the Metal Printing Process, MPP

The metal printing process, MPP; is a novel Rapid Manufacturing process under development at SINTEF and NTNU in Trondheim, Norway. The process, which aims at the manufacturing of end-use products for demanding applications in metallic and CerMet materials, consists of two separate parts; The layer fabrication, based on electrostatic attraction of powder materials, and the consolidation, consisting of the compression and sintering of each layer in a heated die. This approach leads to a number of issues regarding the interaction between the process solutions and the materials. This paper addresses some of the most critical material issues at the current development stage of MPP, and the present solutions to these.Mechanical Engineerin

From piles to tiles: designing for overview and control in case handling systems

Poor overview and control of workload in electronic case handling systems is a potential health risk factor which affects the users. Case handling systems must therefore be designed to give the users a better overview and maximum control over their workload. In an earlier study, we developed a prototype interface for managing cases, based on the piles metaphor. This paper introduces a second prototype, which is designed to incorporate the findings of an evaluation of the piles metaphor prototype. In this second prototype cases are visualized as “tiles”, reflecting the number and complexity of the cases. This paper also describes some the results of the evaluation of the tiles prototype

A trusted analyst’s opinion is worth gold for a company’s investors

It weighs more than a respected CEO's word, write Steven Boivie, Scott D. Graffin and Richard Gentr

SGXIO: Generic Trusted I/O Path for Intel SGX

Application security traditionally strongly relies upon security of the underlying operating system. However, operating systems often fall victim to software attacks, compromising security of applications as well. To overcome this dependency, Intel introduced SGX, which allows to protect application code against a subverted or malicious OS by running it in a hardware-protected enclave. However, SGX lacks support for generic trusted I/O paths to protect user input and output between enclaves and I/O devices. This work presents SGXIO, a generic trusted path architecture for SGX, allowing user applications to run securely on top of an untrusted OS, while at the same time supporting trusted paths to generic I/O devices. To achieve this, SGXIO combines the benefits of SGX's easy programming model with traditional hypervisor-based trusted path architectures. Moreover, SGXIO can tweak insecure debug enclaves to behave like secure production enclaves. SGXIO surpasses traditional use cases in cloud computing and makes SGX technology usable for protecting user-centric, local applications against kernel-level keyloggers and likewise. It is compatible to unmodified operating systems and works on a modern commodity notebook out of the box. Hence, SGXIO is particularly promising for the broad x86 community to which SGX is readily available.Comment: To appear in CODASPY'1

Side differences in cerebrovascular accidents after cardiac surgery: A statistical analysis of neurologic symptoms and possible implications for anatomic mechanisms of aortic particle embolization

BackgroundAortic manipulation and particle embolization have been identified to cause cerebrovascular accidents in cardiac surgery. Recent data suggest that left-hemispheric cerebrovascular accident (right-sided symptoms) is more common, and this has been interpreted as being caused by aortic cannula stream jets. Our aim was to evaluate symptoms of cerebrovascular accident and side differences from a retrospective statistical analysis.MethodsDuring a 2-year period, 2641 consecutive cardiac surgery cases were analyzed. Patients positive for cerebrovascular accident were extracted from a database designed to monitor clinical symptoms. A protocol was used to confirm symptom data with the correct diagnosis in patient records. Patients were subdivided into 3 groups: control, immediate cerebrovascular accident, and delayed cerebrovascular accident.ResultsAmong pooled patients, immediate and delayed cerebrovascular accidents were 3.0% and 0.9%, respectively. The expected predisposing factors behind immediate cerebrovascular accidents were significant, although the type of operation affected this search. Aortic quality was a strong predictor (P < .001). The rate of delayed cerebrovascular accident was unaffected by surgery group. Left-sided symptoms of immediate cerebrovascular accident were approximately twice as frequent (P = .016) as on the contralateral side. This phenomenon was observed for pooled patients and for isolated coronary bypass procedures (n = 1882; P = .025).ConclusionsImmediate cerebrovascular accident and aortic calcifications are linked. The predominance of left-sided symptoms may suggest that aortic manipulation and anatomic mechanisms in the aortic arch are more likely to cause cerebrovascular accidents than effects from cannula stream jets

Intraluminal aortic manipulation by means of intra-aortic filter, cannulation, and external clamp maneuvers evaluated versus dislodged embolic material

ObjectivesAortic atherosclerosis is an important risk factor for cerebrovascular accidents in cardiac surgery. An intra-aortic filter might reduce this risk. We aimed to analyze the risks for emboli associated with intraluminal aortic manipulation and intra-aortic filter handling in relation to cannulation and external clamp maneuvers.MethodsA model was designed with a cadaver aorta and retrograde perfusion (n = 16). A crossclamp was positioned on the ascending aorta and repeatedly opened under pressure to collect aliquots with dislodged particles. Cannulation was performed after 10 clamp maneuvers, followed by positioning and removing the intra-aortic filter, with each step followed by a washout sequence to collect perfusate. The removed filter was also analyzed. Evaluation was by means of digital image analysis, with differentiation of particles into different spectra.ResultsIntra-aortic filter manipulation produced a significant washout of embolic particles; in particular, this was seen for the macroscopic cellular spectrum (P = .006 and P = .002 for filter insertion and removal, respectively). Particles were also found to be collected by the filter (P = .004). In addition, cannulation and aortic crossclamp manipulation generated a notable number of particles (P = .001 and P = .013, respectively).ConclusionsThe intra-aortic filter collects material during aortic manipulation. However, intraluminal aortic manipulation from filter handling can also dislodge particles, possibly related to shedding of intimal debris. This is in addition to substantial amounts of particles that are generated by aortic cannulation and aortic crossclamping

Smart Spare Parts Management – A digital supply network perspective

As additive manufacturing (AM) is being utilized across various sectors, value chains are disrupted and new approaches to spare parts management can be adopted. This report provides an introduction to the state-of-the-art regarding AM for the production of spare parts, along with complementary technologies including digital warehouses and distributed manufacturing. Initiatives in certification and qualification are described, and the need for competency is emphasized as a pivotal enabler for the industry to harvest the potential of AM for spare parts management in the coming years.publishedVersio

Systems development methods and usability in Norway: An industrial perspective

This is the post-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2007 Springer Berlin HeidelbergThis paper investigates the relationship between traditional systems development methodologies and usability, through a survey of 78 Norwegian IT companies. Building on previous research we proposed two hypotheses; (1) that software companies will generally pay lip service to usability, but do not prioritize it in industrial projects, and (2) that systems development methods and usability are perceived as not being integrated. We find support for both hypotheses. Thus, the use of systems development methods is fairly stable, confirming earlier research. Most companies do not use a formal method, and of those who do, the majority use their own method. Generally, the use of methods is rather pragmatic: Companies that do not use formal methods report that they use elements from such methods. Further, companies that use their own method import elements from standardised methods into their own

Serving on corporate boards plays a vital role in the career success of executives

They're more likely to be promoted as first-time CEOs and to get a raise, even without a promotion, write Steven Boivie, Scott D. Graffin, Abbie G. Oliver and Michael C. Wither