Tradeoff behavior

An ideal gas separation membrane must have high permeability and high selectivity. The gas permeation properties of polymer membranes have been extensively smdied, and a wide variety of polymers have been synthesized to be more permeable and selective. Nevertheless, there are stiU strong trade-off relations of gas permeability and selectivity in polymer membranes that will not easily be broken in the fiimre. Moreover, this tradeoff behavior of polymer membranes is not yet fully comprehended theoretically. However, it is beheved that this trade-off behavior for specific gas pairs is unique and related to parameters of the gas molecules. 

However, as mentioned in the previous section, the stochastic model takes a decision based on first-stage and expected second-stage costs, and, hence, does not account for the decision-maker risk behavior (risk-averse or risk taker). For this reason, a more realistic approach would consider higher moments where the tradeoff between the mean value and the variations of different scenarios is appropriately reflected. 

Michael Schrage, of the Massachusetts Institute of Technology, emphasized the importance of human behavior to the economics of and the tradeoffs associated with modeling. Schrage discussed how innovation is based on how people behave around versions of models, rather than solely on the model itself. 

Assuming that an innovation opportunity can be modeled in some useful and meaningful way, I am interested in exploring how people behave with respect to the economics of and the tradeoffs associated with modeling. My particular emphasis is on innovation behavior, looking not at how people think but at how people behave. Actions speak louder than words. Actual behavior is more eloquent and revealing than rigorous analysis. 

The filter bank used in the MPEG/Audio coding system will be used as an example. A 511 tap prototype filter is used. Figure 2.7 shows the prototype filter (window function). It has been optimized for a very steep filter response and a stop band attenuation of better than 96 dB. Figure 2.8 shows the frequency response of the filter bank. In addition to the attenuation requirements it was designed as a reasonable tradeoff between time behavior and frequency localization [Dehery, 1991],... 

The optimum conditions yield a weak onesided maximum of the centerline deposition rate. The deposition rate falls linearly at pressures well below the optimum value, but remains nearly constant at all values above. The reason for this behavior lies in the tradeoff... 

In the field of Virtual Environments, this is a severe constraint, as these applications require a real-time environment to run in. This can usually not be fulfilled and is stated in the Consistency-Throughput Tradeoff [966] It is impossible to allow dynamic shared state to change frequently and guarantee that all hosts simultaneously access identical versions of that state . As such it states that a dynamic VE can not support dynamic behavior and consistency across all connected sites simultaneously. 

Davidson and Ponsonby [55] studied the influence of the degree of crosslinking in a polythiophene derivative on its conductivity (Fig. 9.23(b),). With increasing degree of crosslinking they found an oscillatory behavior of the conductivity. This was explained by a tradeoff between more conductive pathways (good) and less intrachain planarity (bad). 

In section 9.3.2, determinism was identified as a safety design feature for automated controllers. Consistenqr, however, requires more than deterministic behavior. If the operator provides the same inputs but different outputs (behaviors) result for some reason other than what the operator has done (or may even know about), then the behavior is inconsistent from the operator viewpoint even though it is deterministic. While the designers may have good reasons for including inconsistent behavior in the automated controller, there should be a careful tradeoff made with the potential hazards that could result. 

Simultaneous dynamic optimization. In order to validate this approach, the sjm-thesis of MTBE is used as case study. Three spatial variables and sixteen control-related parameters were optimized during a time horizon of 14400 s. A tradeoff between control and economic performances exists in the design of RD processes, as shown in table 6.5. The design optimized sequentially with respect to dynamic behavior led to a RD process... 

Formulating design as a dynamic optimization problem, we found that for the synthesis of MTBE, a tradeoff between control and economic performances exists. We solved this multiobjective optimization problem by incorporating appropriate time-invariant parameters e.g. column diameter, heat transfer areas and controllers parameters) in the frame of a dynamic optimization problem in the presence of deterministic disturbances. The design optimized sequentially with respect to dynamic behavior leads to a RD process with a total annualized cost higher than that obtained using simultaneous optimization of spatial and control structures. 

In a performance-based approach to build structures, all decisions, choices, and tradeoffs start with the required behavior-in-use rather than prescribed solutions for how to meet the stated needs. The supplier responds with an offering that includes the estimated performance of that offering. A validation method, through measurement, calculation, or testing, is necessary to evaluate the performance (over time) and to compare alternative solutions (Szigeti Davis, 2005). The design/build team must warrantee and main-... 

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