Computerised trace method for establishing equations for dimensions and tolerances in design and manufacture

A computerised trace method has been developed for determining the relationships of assembly requirements with design dimensions and tolerances of the components in an assembly, and the relationships of design specifications and machining allowance requirements with manufactured dimensions and tolerances of the component in a process plan. This method traces from the proposed components or planned operations only the dimensions and tolerances that affect the given requirement, and therefore the equations for design or for manufacture can be established simultaneously and accurately. Hence it is possible to establish constraints for the optimisation of dimensions and tolerances for design or for manufacture.     

Design Errors: Inefficiency or Carelessness of Designer?

Design defects are experienced in many projects; the difference is only in the extent of occurrence. This technical note discusses a design error case in a building project in Nepal, where the designer made the wrong assumptions in roof treatment work for waterproofing as well as for heat insulation purposes. From the investigation of the problem, it was found that the waterproofing polymer was not applied directly over concrete slab top. Use of heavy concrete block as a heat insulation material also helped to increase the leakage problem. The problem evoked loss of prestige for project officials, the design consortium, and the contractor.     

Use of Response Surface Methodology to Investigate the Effectiveness of Commercial Enzymes on Buckwheat Malt for Brewing Purposes

The influence of two factors, total concentration and fraction of three pairs of commercial enzymes, which showed statistical significance (Biocellulase W with Hitempase 2XL, Biocellulase W with Amylo 300 and Amylo 300 with Hitempase 2XL), were studied for their overall effect on buckwheat wort quality using response surface methodology (RSM). This study revealed that the addition of increasing levels of Hitempase 2XL to the buckwheat mash increased colour, extract levels, wort filtration, fermentability and total fermentable extract (TFE), along with decreasing viscosity values. Results also determined a high level of fermentability when an enzyme combination of 30% Biocellulase and 70% Hitempase was added to the mash. The addition of increasing levels of Amylo 300 to buckwheat mashes resulted in increases in fermentability and total fermentable extract (TFE), along with increases in total soluble nitrogen (TSN), free amino nitrogen (FAN) and Kolbach index (KI). With regard to the proposed optimal regime, although no synergistic effect was found when the three enzymes were used together, the optimum conditions for the production of buckwheat wort with lowest viscosity, highest extract and optimal fermentability were achieved using a joint model. Overall, the findings of this study demonstrate the feasibility of producing wort suitable for the brewing of gluten‐free beer from 100% malted buckwheat with careful optimisation of enzyme types and dosage levels.     

MEMORY·童年·印象--合肥市政务文化新区儿童公园概念性方案

合肥市政务文化新区儿童乐园的概念性方案,充分考虑了儿童的心理和成长交流需要,以儿童的自发活动为特色,兼顾各类活动设施,创造丰富活动空间,构筑了一个富有感染力、空间变幻多彩的都市儿童乐园.     

Design optimization of 3D steel structures: Genetic algorithms vs. classical techniques

In this paper an elitist genetic algorithm (GA) developed by the authors is compared with common commercial solutions for complex structural optimization. After its prior validation on two-dimensional (2D) structures, the GA was tuned and improved in order to obtain structural elements with minimum weights that satisfy the ultimate limit states of the applicable building code. Subsequently, the same spatial structures were optimized using a commercial structural analysis program. Finally, the cost and weight improvements obtained using the GA, although at a higher computational cost, are discussed.     

Effect of Calcium Lactate, 4-Hexyl Resorcinol and Vacuum Packing on Physico-chemical, Sensory and Microbiological Qualities of Minimally Processed Litchi (Litchi chinensis Sonn.)

Litchi (Litchi chinensis Sonn.) fruits are very susceptible to pericarp browning which adversely affects consumer acceptability even though the aril portion remains in excellent condition. Litchi arils (litchis) were treated with a solution containing 0–2% (w/v) calcium lactate (CL), 0–0.02% (w/v) 4‐hexyl resorcinol (4‐HR) and 1% potassium sorbate. The pH of solution was adjusted to 4.0 with citric acid. Treated litchis were packed in polystyrene trays, over‐wrapped with polypropylene film, vacuum‐packed (0, 47409.3, 94831.9 Pa) and stored at 4 ± 2 °C. Drip losses, pH, total soluble solids (TSS), sensory attributes and microbiological quality of stored samples were estimated. A four‐factor, three‐level experimental design (D₆ Hokes design) with 19 experiments was chosen. Mathematical models were developed to analyse and predict the effect of CL, 4‐HR, in‐package vacuum and storage time on the responses. TSS, pH and sensory scores decreased significantly (P 0.01), whereas drip losses and microbial count increased significantly (P 0.01) with time. Drip loss was significantly (P 0.1) reduced by addition of CL. 4‐HR prevented browning and changes in colour score during storage were significantly less. Vacuum in packages exerted significant (P 0.01) effect over pH, TSS, sensory and microbiological qualities of minimally processed litchis.     

Identifying a Design Management Package to Support Concurrent Design in Building Wafer Fabrication Facilities

Concurrent design is commonly used in building a semiconductor wafer fabrication facilities to shorten projects. Current practice in managing a design schedule involves preset milestones that represent percentages of completion. Such a simple control scheme does not provide sufficient information to support concurrent design. This study presents an analytical model that applies a cluster identification algorithm to separate the work of designing a multisystem project into management packages that support concurrent design. Tasks within a package have strong informational dependency relationships on each other, and are not suited for concurrent design. Tasks of different packages have weak dependency relationships on each other, and are suited for concurrent design. Tendering design work based on these packages may reduce the number of design interfaces between participating design firms. Possible application of the model includes the management of design schedule, design contract tendering, and design information flow.     

Emulsifying Capacity and Emulsion Stability of Soy Proteins Compared with Corn Germ Protein Flour

Both emulsifying capacity (EC) and emulsion stability (ES) increased with increasing concentrations from 0.4% to 0.8% of soy flour (SF), soy concentrate (SC), soy isolate (SI) and corn germ protein flour (CGPF) when studied by response surface methodology. EC and ES increased as pH increased from 6 to 8 in all samples. Increasing incubation temperatures of protein solutions from 20–70°C or from 4–20°C did not affect EC or ES, respectively. SF had the highest EC, followd by SI, SC, and CGPF.     

漫谈汽车产品的包装

从汽车外形设计、车身色彩及内装饰三个方面讨论汽车内外包装的发展现状和有关走向，并指出这方面正有迅猛的发展势头，以上起包装界和汽车设计界的高度重视。     

The thermodynamic performance of a new solution cycle in double absorption heat transformer using water/lithium bromide as the working fluids

In this paper, a new solution cycle in the double absorption heat transformer is presented and the thermodynamic performance of this new cycle is simulated based on the thermodynamic properties of aqueous solution of lithium bromide. The results show that this new cycle is superior to the cycle being studied by some researchers. This new solution cycle has a wider range of operation in which the system maintains the high value of COP and has larger temperature lifts and operation stability. The relationship between the absorber and the absorbing evaporator is more independent and this makes the operation and control of the system more easier.