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Flood flushing is one natural cleansing capability of a natural river channel to wash away in‐stream pollutants and debris. The purpose of this paper is to explore the flood flushing restriction in a tributary due to its regulated main river channel between two barrages.

In the absence of detailed data, a concerted effort of computer river modelling is conceptualized to represent possible flushing conditions.

Regulation schemes of barrages are deduced to interrupt the natural tidal and river flow interaction zones and thus impede river flushing capability.

Modelling of barrages’ operating modes suggested that though the man‐made structures are unable to replicate natural flood flushing, proper operations offer a secondary option to achieving the desired water quality objective in a constrained tributary.

Studies on minor tributary of modified main‐stem river are few. The attended tributary‐trunk relationships carry the credibility of this paper.

Sishen Iron Ore Mine in the Northern Cape province of South Africa utilises 72 primary equipment units to move 119Mt of materials per year, of which 32.5Mt of run‐of‐mine material are sent to the processing plant. The maintenance mission, philosophy and strategy of the Mine are outlined as a background to the discussion of the application of tribology principles. The evolution of Sishen’s tribology outlook is described up to the current position, where the vision for the future is: “no wear”. The current maintenance activities are discussed under the headings: contamination control, lubricants, growing awareness, flushing equipment, and breathers. The results achieved are described, together with the calculated return on investment. Finally, the requirements for success are outlined and possible pitfalls listed.

Coordination feature (CF) is the information carrier in dimension and shape transfer process in aircraft manufacturing. The change of its geometric size, shape, position or other attributes would affect the consistency of accumulated errors between two or more assemblies. To identify these “key characteristics” that have a close relationship with the assembly precision, a comprehensive method was developed under digital manufacturing environment, which was based on importance calculation. The multi-hierarchy and multi-station assembly process of aircraft products were also taken into consideration.

First, the interaction and evaluation relationship between components at different manufacturing stages was decomposed with a hierarchical net. Second, to meet coordination accuracy requirements, with the integrated application of Taguchi quality loss function, accuracy principal and error correction coefficient H, the quality loss between target features and candidate features at adjacent assembly hierarchies were calculated, which was based on their precision variation. Third, the influence degree and affected degree of the features were calculated with DEMATEL (decision-making trial and evaluation laboratory) method, and the concepts of centrality degree index and cause degree index were proposed for calculating the complete importance degree to eventually identify the CFs.

Based on the proposed methodology, CFs, affecting the skin profile and the flush coordination accuracy, were successfully identified at different assembly hierarchies to a certain type of wing flap component.

Benefit results for the engineering application showed that the deviation of skin profile was more accurate than before, and the tolerance was also closer to the centerline of required assembly precision range. Moreover, the stability in the assembly process was increased by 26.9 per cent, which could bring a higher assembly quality and an enhancement on aircraft’s flight performance.

The Secretary of State—

LIBRARIANSHIP is an established profession, international in scope, and currently passing through a period of acute shortage of trained personnel. The City of Liverpool, situated at the gate‐way of the New World, has given its School of Librarian‐ship some of the elements of its international character, while the current dearth of librarians has given it the opportunity to expand.

THE Rainbow is the commercial adaptation of the XF‐12 photographic aeroplane the Republic Aviation Corporation completed for the Army Air Forces. In 1943, the Photographic Section of the A.A.F. issued specifications for a new multi‐engined, long‐range, high‐speed, reconnaissance aeroplane to fly at very high altitudes. The required performance was so much beyond anything in existence at the time that it posed a real problem to designers of high performance aeroplanes. Republic engineers, who for years had specialized in high‐altitude, high‐speed pursuit planes, eagerly accepted the challenge. After exhaustive studies it was found that the performance required by the specification could only be met with a four‐engined machine using Pratt and Whitney R‐4360 engines, supercharged to carry full military power to 40,000 ft. Other combinations would either fail in speed, or in range, or in desired rate of climb or ceiling. A proposal based on four 4360 engines was submitted to the A.A.F., and in March 1944, the Company was awarded a contract for two XF‐12 aircraft. The first prototype was completed in December, 1945, and made its first flight on February 4, 1946.

This paper describes the benefits of vision guided robotics when applied in four industrial manufacturing case studies relating to plastics industries. These include trimming, welding, degating and deflashing operations.

The purpose of this study is to demonstrate and characterise a soft-tooled micro-injection moulding process through in-line measurements and surface metrology using a data-intensive approach.

A soft tool for a demonstrator product that mimics the main features of miniature components in medical devices and microsystem components has been designed and fabricated using material jetting technique. The soft tool was then integrated into a mould assembly on the micro-injection moulding machine, and mouldings were made. Sensor and data acquisition devices including thermal imaging and injection pressure sensing have been set up to collect data for each of the prototypes. Off-line dimensional characterisation of the parts and the soft tool have also been carried out to quantify the prototype quality and dimensional changes on the soft tool after the manufacturing cycles.

The data collection and analysis methods presented here enable the evaluation of the quality of the moulded parts in real-time from in-line measurements. Importantly, it is demonstrated that soft-tool surface temperature difference values can be used as reliable indicators for moulding quality. Reduction in the total volume of the soft-tool moulding cavity was detected and quantified up to 100 cycles. Data collected from in-line monitoring was also used for filling assessment of the soft-tool moulding cavity, providing about 90% accuracy in filling prediction with relatively modest sensors and monitoring technologies.

This work presents a data-intensive approach for the characterisation of soft-tooled micro-injection moulding processes for the first time. The overall results of this study show that the product-focussed data-rich approach presented here proved to be an essential and useful way of exploiting additive manufacturing technologies for soft-tooled rapid prototyping and new product introduction.

Reviews the relationship between building design and crime. Presents evidence that anti‐social activity is encouraged by bad design. Tabulates features that are “beneficial” and “adverse”. Cites examples where design improvement (DI) has led to a reduction in crime. Concludes that though DI has an initial cost, it tackles the root cause of anti‐social behaviour and benefits the community in quality of life and saves money.

AA2014 is a copper-based alloy and is typically used for production of complex machined components, given its better machinability. The purpose of this paper was to study the effects of variation in weight percentage of ceramic Al₂O₃ particulates during electrical discharge machining (EDM) of stir cast AA2014 composites. Scanning electron microscopy (SEM) examination was carried out to study characteristics of EDMed surface of Al₂O₃/AA2014 composites.

The effect of machining parameters on performance measures during sinker EDM of stir cast Al₂O₃/AA2014 composites was examined by “one factor at a time” (OFAT) method. The stir cast samples were obtained by using three levels of weight percentage of Al₂O₃ particulates, i.e. 0 Wt.%, 10 Wt.% and 20 Wt.% with density 1.87 g/cc, 2.35 g/cc and 2.98 g/cc respectively. Machining parameters varied were peak current (1-30 amp), discharge voltage (30-100 V), pulse on time (15-300 µs) and pulse off time (15-450 µs) to study their influence on material removal rate (MRR), tool wear rate (TWR) and surface roughness (SR).

MRR and SR decreased with an increase in weight percentage of ceramic Al₂O₃ particulates at the expense of TWR. This was attributed to increased microhardness for reinforced stir cast composites. However, microhardness of EDMed samples at fixed values of machining parameters, i.e. 9 amp current, 60 V voltage, 90 µs pulse off time and 90 µs pulse on time reduced by 58.34, 52.25 and 46.85 per cent for stir cast AA2014, 10 Wt.% Al₂O₃/AA2014 and 20 Wt.% Al₂O₃/AA2014, respectively. SEM and quantitative energy dispersive spectroscopy (EDS) analysis revealed ceramic Al₂O₃ particulate thermal spalling in 20 Wt.% Al₂O₃/AA2014 composite. This was because of increased particulate weight percentage leading to steep temperature gradients in between layers of base material and heat affected zone.

This work was an essential step to assess the machinability for material design of Al₂O₃ reinforced aluminium metal matrix composites (AMMCs). Experimental investigation on sinker EDM of high weight fraction of particulates in AA2014, i.e. 10 Wt.% Al₂O₃ and 20 Wt.% Al₂O₃, has not been reported in archival literature. The AMMCs were EDMed at variable peak currents, voltages, pulse on and pulse off times. The effects of process parameters on MRR, TWR and SR were analysed with comparisons made to show the effect of Al₂O₃ particulate contents.