Process Development

Summary Previous studies by other researchers in this discipline provide a set of axiom and supporting models for software assessment and quality but are not extended to a practical and well accepted model of certification. During the last five years, two preliminary works was undertaken in this research group to study issues of certification and these works are still continuing. Recently, this initial work was completed and extended. Two software certification models have been developed using requirements-design- implementation strategy to ensure that it meets the needs of a number of different interest groups in the industry. The two models focused on certifying software by development process and product quality approaches. The models have been tested by case study, which was launched collaboratively with industry in Malaysia. Further analysis has demonstrated feasibility and practicality of the models in a real environment. This paper discusses the implementation of these two mo...

In the European FP6 research project CACHET palladium-based hydrogen membrane reactors for pre-combustion CO2 capture from natural gas combined cycles are being developed. In the project both the electroless plating method used by DICP and the SINTEF two-stage membrane preparation method based on magnetron sputtering have been successfully up-scaled to produce membranes with a length of 50 cm. The membranes

The concept of mass customisation is not new yet the UK construction industry has yet to grasp this opportunity to deliver greater value to its customers. The government report Rethinking Construction [Egan 1998] clearly identifies this issue:'We have repeatedly heard the claim that construction is different from manufacturing because every product is unique. We do not agree. Not only are many buildings such as houses, essentially repeat products which can be continually improved but, more importantly, the process of construction is ...

The recent advancement in high performance semiconductor packages has been driven by the need for higher pin count and superior heat dissipation. A one-piece cavity lid flip chip BGA package with high pin count and targeted reliability has recently been developed by UTAC. The flip chip technology can accommodate I/O count of more than five hundreds, and the die junction temperature can be reduced to a minimum level by a metal heat spreader attachment. Nonetheless, greater expectations on these high performance packages arose such as better substrate land estate utilization for multiple chips, ease in handling for thinner core substrates and improved board level solder joint reliability. A new design of the flip chip BGA package has been looked into for meeting such requirements. By encapsulating the flip chip with molding compound leaving the die top exposed, a planer top surface can be formed. And a flat lid can then be mounted on the planer mold/die top surface. In this manner the direct interaction of the metal lid with the substrate can be removed. The new package is thus less rigid under thermal loading and solder joint reliability enhancement is expected. This paper discusses the process development of the new package and its advantages for improved solder joint fatigue life, and being a multi-chip package and thin core substrate options. Finite element simulations have been employed for the study of its structural integrity, thermal and electrical performances. Detailed package and board level reliability test results will also be reported.

ABSTRACT: The current economic developments have led to substantial changes in terms of how the financial and accounting activities are carried. The business environment can be characterized by a widespread consolidation of companies and their grouping in holding companies. ...

The present paper tries to contribute to quantifying the relationship between the amount of corrosion and cover cracking. The variables studied were: cover/diameter (c/ø), proportions of cement, w/c, cast position of the bar, transverse reinforcement and corrosion rate. The corrosion is accelerated by applying constant currents causing the rebar to act as an anode. The results indicate that the cracking process develops in two steps: generation and propagation. Radius losses of about 15–50 μm are necessary to generate the first visible crack ( Ce travail tente de quantifier la relation entre le degré de corrosion et la fissuration du recouvrement de l'armature. Les variables étudiées ont été: recouvrement/diamètre (c/ø), dosage du ciment, eau/ciment, position de l'armature, armature transversale, et degré de corrosion. La corrosion est accélérée par l'application des courants constants qui font agir l'armature comme une anode. Les résultats indiquent que le processus de fissuration se développe en deux temps: génération et propagation. Une réduction du rayon de l'armature d'environ 15–50 μm est nécessaire pour produire la première fissure visible (ouverture

Biotechnology process development involves strain testing and improvement steps aimed at increasing yields and productivity. This necessitates the high-throughput screening of many potential strain candidates, a task currently mainly performed in shake flasks or microtiter plates. However, these methods have some drawbacks, such as the low data density (usually only end-point measurements) and the lack of control over cultivation conditions in standard shake flasks. Microbioreactors can offer the flexibility and controllability of bench-scale reactors and thus deliver results that are more comparable to large-scale fermentations, but with the additional advantages of small size, availability of online cultivation data and the potential for automation. Current microbioreactor technology is analyzed in this review paper, focusing on its industrial applicability, and directions for future research are presented.

A comparative study on weak anion exchangers was performed to investigate the pH dependence, binding strength, particle size distribution, and static and dynamic capacity of the chromatographic resins. The resins tested included: DEAE Sepharose FF, Poros 50 D, Fractogel EMD DEAE (M), MacroPrep DEAE Support, DEAE Ceramic HyperD 20, and Toyopearl DEAE 650 M. Testing was performed with five different model proteins: Anti-FVII mAb (immunoglobulin G), aprotinin, bovine serum albumin (BSA), Lipolase (Novozymes), and myoglobin. Retention showed an expected increasing trend as a function of pH for proteins with low pI. A decrease in retention was observed for some resins at pH 9 likely due to initiation of deprotonation of the weak anion-exchange ligands. Expected particle size distribution was obtained for all resins compared to previous studies. Binding strength to weak anion-exchange resins as a function of ionic strength depends on the specific protein. Binding and elution at low salt concentration may be performed with Toyopearl DEAE 650 M, while binding and elution at high salt concentration may be performed with MacroPrep DEAE Support. Highest binding capacities were generally obtained with Poros 50 D followed by DEAE Ceramic HyperD 20. A general good agreement was obtained between this study and data obtained by the suppliers. Verification of binding strength trends with model proteins was achieved with human growth hormone (hGH) and a hGH variant on the same resins with different elution salts, sodium chloride, sodium hydrogenphosphate, sodium sulphate, and sodium acetate. Static capacity measurements obtained in the traditional experimental set-up were compared with high-throughput screening (HTS) technique experiments with reasonable agreement. Isotherm data obtained from HTS techniques and pulse experiments were successfully combined with mathematical modelling to simulate, develop and optimise the separation process of two model proteins, Lipolase and BSA. The data presented in this paper may be used for selection of resins for testing in process development.

The development of large software systems is a complex and error prone process. Faults can occur at any development stage and they shall be identified and removed as early as possible to stop their propagation and reduce verification cost. Quality engineers must be involved in the development process since the very early phases to identifying the required qualities and estimate their impact on the development process. Their task span over the whole development cycle and goes beyond the product deployment through ...