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This study aims to optimize the preparation conditions and modify the nanofiltration (NF) membranes to prepare high-performance polysulfone/sulfonated polysulfone composite nanofiltration (PSF/SPSF-NF) membranes through interfacial polymerization.

Investigating the impacts of anhydrous piperazine (PIP) concentration, trimesoyl chloride (TMC) concentration and basement membrane type on NF membrane performance, the optimal membrane was prepared. In addition, nano-SiO₂ was added to the active separation layer to modify the NF membranes.

The comprehensive performance of PSF/SPSF-NF membranes was optimized when the concentration of PIP was 0.75 Wt.% and the concentration of TMC was 0.15 Wt.%, at which time the water flux was 66.1 L·m⁻²·h⁻¹ and the retention rate of Na₂SO₄ was 98.1%. The comprehensive performance of polysulfone/sulfonated polysulfone-SiO₂ nanofiltration (PSF/SPSF-SiO₂-NF) membranes was optimized when the blending ratio of nano-SiO₂ to PIP was 2:3, with a pure water flux of 81.9 L·m⁻²·h⁻¹ and a Na₂SO₄ retention rate of 95.9%. Compared to polysulfone nanofiltration (PSF-NF) membranes and PSF/SPSF-NF membranes, NF membranes with nano-SiO₂ increased the flux recovery rate by 22.9% and 8.7%.

PSF/SPSF-SiO2-NF membrane exhibits excellent antifouling properties.

There is currently no literature available on the preparation of NF membranes using polysulfone/sulfonated polysulfone (PSF/SPFS) as a substrate. This provides a method for modifying NF membranes, starting with the modification of the basement membrane and then modifying the active separation layer.

This paper gives a bibliographical review of the finite element and boundary element parallel processing techniques from the theoretical and application points of view. Topics include: theory – domain decomposition/partitioning, load balancing, parallel solvers/algorithms, parallel mesh generation, adaptive methods, and visualization/graphics; applications – structural mechanics problems, dynamic problems, material/geometrical non‐linear problems, contact problems, fracture mechanics, field problems, coupled problems, sensitivity and optimization, and other problems; hardware and software environments – hardware environments, programming techniques, and software development and presentations. The bibliography at the end of this paper contains 850 references to papers, conference proceedings and theses/dissertations dealing with presented subjects that were published between 1996 and 2002.

Presents a review on implementing finite element methods on supercomputers, workstations and PCs and gives main trends in hardware and software developments. An appendix included at the end of the paper presents a bibliography on the subjects retrospectively to 1985 and approximately 1,100 references are listed.

This paper aims to deal with the development of a software tool to simulate and study vehicle – road interaction (VRI) to quantify the forces induced and energy released from vehicles to the road pavement, in different vehicle motion scenarios, and the energy absorbed by the road surface, speed reducers or a specific energy harvester surface or device. The software tool also enables users to quantify the energetic efficiency of the process.

Existing software tools were analysed and its limitations were identified in terms of performing energetic analysis on the interaction between the vehicle and the road pavement elements, such as speed reducers or energy harvest devices. The software tool presented in this paper intends to overcome those limitations and precisely quantify the energy transfer.

Different vehicle models and VRI models were evaluated, allowing to conclude about each model precision: bicycle car model has a 60 per cent higher precision when compared with quarter-car model, and contact patch analysis model has a 67 per cent higher precision than single force analysis model. Also, a technical study was performed for different equipment surface shapes and displacements, concluding that these variables have a great influence on the energy released by the vehicle and on the energy harvested by the equipment surface.

The developed software tool allows to study VRI with a higher precision than existing tools, especially when energetic analyses are performed and when speed reduction or energy harvesting devices are applied on the pavement.

Enterprise software is a predominant sector in the European software industry. Four of the five largest European software companies are found in this sector. Interestingly, two of these — among them SAP as one of the two global market leaders — are located within the same industrial agglomeration in South-Western Germany. This agglomeration, the SAP cluster, further consists of enterprise software SMEs forming a ‘satellite system’ centred around the large players, which fosters the formation of ‘mutualistic symbiotic’ relationships between large and small firms. At first sight, cluster formation in the context of the enterprise software industry might seem perplexing considering that traditional rationales of agglomeration economies seem obsolete in an environment where advances in communications technology would permit companies to locate in any location within a modern developed economy instead of concentrating in proximity to each other or to major players in the industry. This chapter explores possible explanations of this agglomeration phenomenon based on patterns of competition, collaboration and the formation of social capital between smaller firms and large anchor firms.

The findings of a comparative analysis between the SAP cluster environment and two categories of controls (firms in other agglomerated environments and those unaffected by agglomeration effects within Germany) show that SAP cluster SMEs might simultaneously benefit from heightened intensity of competition and a more pronounced inclination towards collaboration. Moreover, the role of social capital derived from SAP as anchor firm clearly differentiates SAP cluster participants from firms located within other environments.

Aims to present a team effectiveness analysis of software development teams and one means of improving the effectiveness of software development teams in quite an innovative manner, namely, by forming teams based on who can work effectively together.

The team roles described by R. Meredith Belbin are utilized to improve the effectiveness of software development teams The procedure used in these analyses consists of: finding teams that indicate a commitment to, or interest in, participating in an analysis of their team; having all team members fill out the Belbin Self‐perception Inventory in order to gather data for analysis; interviewing the leader of the team in order to obtain an independent analysis and verification of the self‐perception data; analyzing the self‐perception data, looking for trends in the data from which subjective assessments can be made; Comparing the Belbin analysis with the interview information, identifying similarities and differences between the two, thus providing verification of the Belbin analysis.

Analyses of software development teams from within the industry demonstrate that Belbin's roles and the Belbin self‐perception inventory can be used to recognize important positive and negative features of a team. Thus, positive features can be encouraged, and negative features can be avoided or remedied.

This paper would be useful to managers and team leaders of software development industries to analyze their team and to bring out superior efforts of forming the team to get the work done.

This paper aims to present a comparison of numerical methods for determining the contact pattern of Gleason-type bevel gears. The mathematical model of tooth contact analysis and the finite element method were taken into consideration. Conclusions have been drawn regarding the usefulness of the considered methods and the compatibility of results. The object of the analysis was a bevel gear characterised by an 18:43 gear ratio and arc tooth line, and manufactured according to the spiral generated modified-roll method.

The mathematical model of tooth contact analysis consists of both the mathematical model of tooth generating and the mathematical model of operating gear set. The first model is used to generate tooth flanks of the pinion and the ring gear in the form of grids of points. Then, such tooth surfaces are used for the tooth contact analysis performed with the other model. It corresponds to the no-load gear meshing condition. The finite element method model was built on the basis of the same tooth flanks obtained with the former model. The commercial finite element method software Abaqus was used to perform two instances of the contact analysis: a very light load, corresponding to the former no-load condition, and the operating load condition. The results obtained using the two models, in the form of the contact pattern for no-load condition, were compared. The effect of heavy load on contact pattern position, shape and size was shown and discussed.

The mathematical models correctly reproduce the shape, position and size of the contact pattern; thus, they can be reliably used to assess the quality of the bevel gear at the early stage of its design.

Determination of the correct geometry of the flank surfaces of the gear and pinion teeth through the observation of contact pattern is a fundamental step in designing of a new aircraft bevel gear.

A possibility of the independent use of the mathematical analysis of the contact pattern has been shown, which, thanks to the compatibility of the results, does not have to be verified experimentally.