Production design criteria

If sufficient data are available, much more information can be provided when different curves for various percentages of failure are plotted. Where such data are available, reasonable design criteria would be based on some probability for failure, depending on how critical the effects of failure occur. If a large, expensive repair of a complex mechanism would result from the fatigue failure of one product, then a 10 or even 1 % probability of failure would be a more likely design criterion than the 50% suggested above. 

Under certain conditions, scale-up of membrane reactors is straightforward. Provided that (i) the reactor contents are well mixed so that the reactor is operated as a CSTR, and that (ii) the membrane is configured for filtration in the tangential mode, the pertinent design criterion, besides constant residence time T in the reactor, is constant fluidity F of the substrate/product solution through the membrane at all reactor scales. Fluidity is defined by Eq. (19.36) (V = ultrafiltered volume, AP = transmembrane pressure, t = filtration time, and A = membrane area). 

Step 1. In this section we alter the control objective relating to production rate. Instead of flow controlling the product stream from the bottom of the stripper, we assume that an upstream process sets the flow of the Fr,c stream and the process must take whatever amount is fed into it. Most of the steps in the design procedure are the same as the previous section, but the control of liquid levels is now in the direction of flow. The product quality criterion is the same. 

Here we should actually check the IC datasheet to see the MAX value of the current limit range. For example, for a 5 A switcher the MIN value may be say 6 A (set high enough simply to guarantee full 5 A load capability with the usual 20% inductor design criterion mentioned above), but the MAX value of the current limit may be say 7 A over temperature and process variations, and depending upon how it may have been trimmed in production. 

It is possible to assume that kinetic and hydrodynamic methods of reactors analysis and design are well advanced at present. Methods of computer simulation and modelling are widely used. So, we can say that if we know processes kinetic and hydrodynamic parameters and fundamental particularities of reactor functioning we can calculate all process characteristics and its stmcture, we also can predict effectiveness of apparatus operation and consumer properties of chemical production. Meanwhile criterion function development for calculation and organization of novel processes and optimization of present productions require overcoming of a big number of problems in production practice. This principle is satisfactory enough for processes with low or medium reactions rates, when creation of isothermal conditions in apparatus is easy. In this case it is easy to calculate and reproduce in working conditions all characteristics of chemical process and to control the last ones. 

The overall coalescence rate of a dispersion/emulsion in a separator is the most important design criterion. Unfortunately, this rate is a product of several complex mechanisms like binary coalescence, interfacial coalescence, and set-tling/creaming. Each of these mechanisms is further related to other even more complex processes/factors like hydrodynamic micro- and macro-motion, droplet size distribution, and interfacial components. In order to understand the overall coalescence rate one must also understand the interactions between these mechanisms. This makes it difficult to separate the overall rate into a sum of distinct rates, and is probably the reason why there exists no generalized coalescence model for concentrated dispersions with a sound theoretical foundation. 

Babensee and co-workers have identified differential levels of dendritic cell maturation on different biomaterials used in combination products. The effect of biomaterials on dendritic cells maturation, and the associated adjuvant effect, is a novel biocompatibility selection and design criterion for biomaterials to be used in combination products in which immune consequences are potential complications or outcomes. 

Compliance with the EN standards is the minimum acceptable criterion for conformity, so I ll start by identifying the appropriate standards (also see Essential Requirements). The science of selecting the appropriate standards can be simple or complicated depending on your experience and product type. Exercise care when identifying the proper standards that may apply to your product design. The selection of a product standard may be a relatively simple task, as for many Low-Voltage Directive (LVD) products, or cumbersome, as for some machines. You must consider the product s intended usage and make sure the product falls within the standard s scope. 

A. General Design Criterion 41 (Reference...) as it relates to containment atmosphere cleanup systems being designed to control fission product releases to the reactor containment following postulated accidents. 

The function of a distribution warehouse is to store products and to fulfill external customer orders typically composed of a large number of order lines (where each order line specifies a quantity of one particular product). The number of different products in a distribution warehouse may be large, while the quantities per order line may be small, which often results in a complex and relatively costly order picking process. Therefore, distribution warehouse are often optimized for cost-efficient order picking. The prominent design criterion is the maximum throughput to be reached at minimum investment and operational costs. 

Target costing A strategic profit planning and cost management system that incorporates a strict focus on customer wants, needs, and values, and translates them into delivered products and services. A variation is using cost as a design criterion in product development. 

Mahe et al. [20] of the LVMH Group, Christian Dior, reported a microstructured device for the production of emulsions on demand. The basic design criterion was that the microstructured device is hand operated, i.e. emulsification has to be achieved with relatively low external forces and internal pressures. Assuming the thumb as most powerful digit, required forces for operation higher than 20 N cannot be accepted. 

We note that with regards to divergence, for example, the systematic aligiunent to a safe state in case of detected failure is generally irrelevant for HIPS whose inadvertent failures can cause other safety issues (risk at restart, water hammer, demands on other safety systems, human error, etc.) excluding production losses, which can be considerable. It follows that beyond the SIL, the probabihfy of a spurious failure is also an important design criterion. 

---