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This paper aims to study a modular method for designing a paste filling station (PFS) for a coal mine (CM) to reduce the PFS’s input cost and achieve reutilization.

Modular design criteria for the PFS are proposed and a modular division (MDiv) model and an evaluation method are established. The correlation-strength matrix of the PFS parts expressed in the form of rough numbers is transformed into a fuzzy equivalent matrix. The theory of rough sets and the fuzzy clustering method are introduced for PFS MDiv. The evaluating method is established for the PFS MDiv scheme based on the principle of fuzzy comprehensive evaluation.

Taking a particular CM PFS as an example, the above method is used to modularize the PFS, and the optimal division of the PFS is finally determined via the above evaluation system. Applying this method solves the problem of high cost investment in the initial stage of PFS construction.

The theory of rough sets and the fuzzy clustering method are introduced for PFS MDiv. An evaluating method is established for the PFS MDiv scheme based on the principle of fuzzy comprehensive evaluation, thereby providing new ideas for PFS transformation and reutilization.

This paper analyzes the characteristics of paste filling material and the parallel output of double pump. By combining the equipment layout of the paste filling station, using the uncertainty fluid topology optimization method based on SIMP to optimize parallel connection structure, we designed the engineering model optimized connection. The optimized connection improves the capacity of the paste filling pump, reduces the filling energy consumption and the load pressure of the pump, and can achieve good economic and social benefits.

The coal reserves overlain by buildings, water bodies and railways are estimated to be about 14 billion tons in China. Based on the concept of green mining, in order to save the unit energy, Double pumps in parallel forms of pumping are adopted in 0the paste filling of the pumping system. The optimal solution of the objective function could be obtained by taking the unit flow power of the pumping system as the objective function, using the quadratic polynomial by the least square method curve fitting and by the application of MATLAB. Thereby it is possible to reduce power consumption and increase the efficiency of the operating economy in the paste filling station.

The main requirements of filling machines for use within the Surface Coatings industry is dictated by the following:

This study aims to present the results of an experimental evaluation of low (M30), mid (M40) and high (M50) grade self-compacting concrete (SCC) with three nominal maximum aggregate sizes (NMAS), namely, 20 mm, 16 mm and 12.5 mm, with Bailey gradation (BG) in comparison with Indian standard gradation (ISG).

This study was conducted in a laboratory by testing the characteristics of fresh and hardened properties of self-compacting concrete.

Rheological and mechanical properties of SCC were evaluated in detail and according to the results, a concrete sample containing lower NMAS with BG demonstrated improvement in modulus of elasticity and compressive strength, while improving the rheological properties as well. Meanwhile, SCC demonstrated poor performance in split tensile and flexural strengths with lower NMAS gradations and a direct correlation was evident as the increase in NMAS caused an increase in the strength and vice-versa.

Upon comparison of BG with ISG, it was revealed that BG mixes succeeded to demonstrate superior performance. From the material optimization, rheological and mechanical performance study, it is recommended that BG with NMAS 16 mm can be used for conventional SCC.

AMI (Affiliated Manufacturers, Inc.) has introduced a new manual vision system for alignment of printed circuit boards to screens or stencils on semi‐automatic screen printers. The u‐Lign™ III allows the operator to select any one of four different alignment methods when setting up for fine pitch solder paste printing. It is even possible to use different strategies in each camera window to accommodate different features at the same time. Alignment is not limited to using fiducial marks or straight edged pads, as virtually any part of a circuit pattern or repeated board markings can be used to achieve precise alignment on every board.

With the increased functional density requirements of military avionics it is impossible to meet these demands without utilising Surface Mount Technology. The Electronics Manufacturing Technology Group at Boeing Military Airplanes is working to meet SMT design requirements through research and development of processes, materials and equipment for all variations of SMT. Basic processes have been established for both 100% SMT and mixed technology. However, the Group continues to advance its capabilities by evaluating and improving all aspects of SMT manufacturing. A description of the initial thrust into Type III SMT as well as subsequent development is given. This includes a description of the evaluation of Surface Mount Component (SMC) attach adhesives comparing the adhesive used initially with others available by examining the various criteria involved in selecting the appropriate one for a given process. Also, a discussion follows of factors involved in determination of Mil‐spec. passive SMCs which are compatible with wave soldering. Included in the evaluation of passive SMCs is a comparison of the compatibility of the wave solder system in use with the component industry's recommended temperature profiles through an analysis based on in‐house testing to determine the actual component endurance to solder system heating. Throughout this discussion emphasis is placed on a systematic guided approach to examining process development.

Although rework is labour intensive and conflicts with most modern manufacturing/assembly philosophies, realistic defect levels in surface mount technology (SMT) printed circuit board (PCB) assembly render rework indispensable on the shop floor. Most commercially available rework tools are manual or require very skilled operators for their efficient operation. The challenges of automating SMD rework are significant because the tools, their specifications and rework processes required are not fully understood, and the impact of rework processes on assembly quality and reliability are hotly debated. This paper describes an automated robotic rework cell for SMD and TH boards, and the method used for process characterisation of the solder paste dispensing system. The paper also describes equipment selection, the integration and interfacing of the dispensing equipment to the cell controller and the process characterisation experiments.

The long‐awaited regulations to provide statutory compositional requirements for the ever‐increasing range of meat products have at last arrived; presented in the form of a triology—The Canned Meat Product Regulations, The Meat Pie and Sausage Roll Regulations and The Sausage and Other Meat Product Regulations—all of which apply to England and Wales only; presumably the Scottish counterparts, modified for the geographical variations in commodities, will appear in due course. The Meat Pie and Sausage Roll Regulations come into operation on May 31 1968; the other two on May 31 1969.

This paper discusses the use of three-dimensional mapping software SolidWorks as a platform to build a parametric model of coal mine filling equipment and a model library of the equipment. The Solidworks software is used to create a near-realistic virtual environment to simulate and analyze the process of building a high-water filling station. In this way, designers can detect potential design flaws early and then optimize the design as much as possible before actual construction.