TRADEOFFS IN DESIGN COMPLEXITY — TEMPORAL VERSUS SPATIAL COMPENSATION

The spectral radiative kernel technique is used to derive spectrally resolved relative humidity (RH) feedbacks for 16 GCMs that participated in CMIP5. Examining spectral and spatial details of these RH feedbacks leads to three findings. First, while the global average of broadband RH feedbacks is close to zero for all the GCMs, there exist wide discrepancies in the spectral details among the GCMs. Second, the spatial pattern of the RH feedbacks varies with spectral frequency; for a given frequency, the spatial feedback pattern correlates well with the spatial pattern of RH changes over the vertical layer to which the top-of-atmosphere spectral flux at the same frequency is most sensitive. Third, the nearly zero global average of broadband RH feedback is a result of spatial compensation and spectral compensation. Since GCMs have produced consistent RH feedbacks and RH changes to a large extent in the high latitudes, the tropical Atlantic, and the deep tropical Pacific, radiative RH kernels are further used to infer mean changes in RH vertical profiles from spectral RH feedbacks averaged over the three broad regions. Good agreements are demonstrated by comparing such inferences against the actual RH changes in the GCMs. This study suggests that the spectral dimension of RH feedback could provide an additional constraint to climate models and the understanding of vertical features of RH changes when they are obtainable from future observations.

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Hybrid Approaches

Application-Layer Fault-Tolerance Protocols ◽

10.4018/978-1-60566-182-7.ch009 ◽

2009 ◽

pp. 275-300

Author(s):

Vincenzo De Florio

Keyword(s):

Fault Tolerance ◽

Design Complexity ◽

Syntactical Structure ◽

Hybrid Approaches ◽

Software Fault Tolerance ◽

Software Fault

This chapter describes some hybrid approaches for application-level software fault-tolerance. All the approaches reported in the rest of this chapter exploit the recovery language approach introduced in Chapter VI and couple it with other tools and paradigms described in other parts of this book. The objective of this chapter is to demonstrate how ReL can serve as a tool to further enhance some of the application- level fault-tolerance paradigms introduced in previous chapters. But why hybrid approaches in the first place? The main reason is that joining two or more concepts and their “system structures” (Randell, 1975), that is, the conceptual and syntactical axioms used in disparate application-level software fault-tolerance provisions, one comes up with a tool with better Syntactical Adequacy (the SA attribute introduced in Chapter II). As already mentioned, a wider syntactical structure can facilitate the expression of our codes, while on the contrary awkward structures often lead to clumsy, buggy applications. Hybrid approaches are often more versatile and can also inspire brand new designs. A drawback of hybrid approaches is that they are modifications of existing designs. The extra design complexity must be carefully added to prevent the introduction if design faults in the architecture.

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FPGA development tools: Keeping pace with design complexity

Field-Programmable Logic Architectures, Synthesis and Applications - Lecture Notes in Computer Science ◽

10.1007/3-540-58419-6_97 ◽

1994 ◽

pp. 271-273

Author(s):

Bradly K. Fawcett ◽

Steven H. Kelem

Keyword(s):

Design Complexity ◽

Development Tools

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