Top-down analysis

A closer examination of the case studies reveals the extreme complexity and inter-hnked nature of the processes in an innovative system. Determining, which were the decisive factors that were manifest by a particular example of substitution, tended to be irresolvable in view of this complexity. A top-down analysis of the systems view of the simple model assists in orientation. In addition, some phenomena that are important for iimovation processes can only be revealed from a systems view, e.g. system inertia and system ambience , which is frequently referred to as the innovation chmate . Decisively, phenomena such as emergence are only discemable at a systems level. Emergence is of central importance for the comprehension of innovation processes, where development of a new element is the core feature. Emergence means that a novel, impredicted and usually complex feature is produced in the system (or by the system) which no individual contributor had planned or could conceivably plan. In most cases, new elements can neither be commanded externally nor can they be negotiated in a discourse between the participants from their estabhshed interests. Creativity is required here. 

The hierarchical approach is a simple but powerful methodology for the development of process flowsheets. It consists of a top-down analysis organized as clearly defined sequence of tasks aggregated in levels. Each level handles a fundamental conceptual problem input/output structure, reactor design, structure of separa-... 

The same concept in proteomics studies has technological implications, e.g., which method, sample preparation protocols, and instrumentation will be used. Again, top-down analysis will be based on isolation, analysis, and characterization of an intact protein to reveal its function. Fourier transformed ion cyclotron resonance mass spectrometry (FT-ICR) (Marshall et al., 1998) facilitates such approach in protein identification as a result of random fragmentation of an intact molecule. In contrary, bottom-up approach is based on up-front fragmentation of the protein in question using various proteolytic enzymes with known specificity (Chalmers et al., 2005 Millea et al., 2006). In these experiments, trypsin is most commonly used. An important question that remains is whether more... 

Top-down analysis is focused on the research of key relations in the whole national economy and on the calculation of CO2 emissions at the country level with the use of models. The starting point for this type of analysis is a set of statistical data regarding macroeconomic quantities, fuel consumption and CO2 emissions. The results focus on quantities describing changes in GDP, energy consumption and CO2 emissions as the country total and in sectoral division. 

The purpose of top-down analysis is to define the number of allowances that are to be allocated to the installations covered by the NAP. 

As discussed above, Table 12.1 compares the final results of bottom-up data collection with top-down analysis. The difference between the emissions estimated with these two approaches was about 2%, indicating that the data collected at the installation level were reliable and could be used to calculate allocation at the sectoral and installation levels. 

GRAI nets are used to further analyze decision centers in terms of their activities, resources, and input-output objects. With this method, a bottom-up aneilysis of the manufacturing systems studied can be made to validate the top-down analysis. In practice, several paths in both ways are necessary to converge to a fined model accepted by aJl concerned business. 

This type of hazards analysis can be either deductive or inductive. A deductive (top-down) analysis is one that first defines an undesirable event, and then considers what events and chains of circumstances are needed to occur before the overall undesirable event occurs. A deductive approach is used by detectives to solve crimes. A widely used type of deductive analysis in process risk analysis is the fault tree method, described in the next chapter. 

A top-down approach is used when management wants to improve overall reliability and/or does not know what the principal causes of problems may be. If a facility manager notes that production losses through unanticipated downtime are increasing, or maintenance costs for the whole facility have increased, he will probably call for a top-down analysis. He may also authorize this type of analysis when he suspects that there is a pervasive root cause problem, such as inadequate operator training, that is affecting many facility subsystems. 

Top-down analysis of large proteins Imaging technique of tissues Petroleomics, humates, fulvates Surface analysis... 

Fault Tree Analysis systems safety technique that utilizes a top down analysis approach, failure trees and Boolean logic. 

The Fault Tree Analysis procedure is a top down analysis procedure that identifies undesirable events and their contributingfactors. Once a tree has been developed, probabilities of failures can be determined for individual components in the tree. With the individual probabilities, overall probabilities of failures can be calculated for event paths using Boolean algebra. 

Typically, two iterations of each analysis should be undertaken to cover human requirements specification and realisation phases and, as the analyses become more focused, the results fiom each one will inform and focus the other. In addition, diese HF activities are entirely complementary as CTA and HEA are bottom-up and top-down analysis techniques respectively (from a hazard to human event perspective).This combination of top-down and bottom-up analyses significantly increases the probability of identifying inconsistencies in the individual techniques and thus enhances safety assurance. 

Once applications are understood and have been documented, the data which those apphcations generate must be examined. In this case, the term data is used in a general sense as today s networks are likely to transport a variety of payloads including voice, video, image, and fax in addition to true data. Data traffic analysis must determine not only the amount of data to be transported, but also must determine important characteristics about the nature of that data. A summarization of data traffic analysis is outlined in Fig. 19.55. It is also during this stage of the top-down analysis in which the geographic proximity of the nodes of the network are examined. 

Given these requirements as determined by the upper layers of the top-down model, the next job is to determine the requirements of the network that will possess the capability to deliver this data in a timely, cost-effective manner. Details on the determination of these requirements comprise the remainder of this section on network communications. These network performance criteria could be referred to as what the implemented network must do in order to meet the business objectives outlined at the outset of this top-down analysis. These requirements are also sometimes referred to as the logical network design. 

As part of the top-down analysis, geographic proximity of computers or network nodes was mentioned as a key piece of analysis information. Although there are no hard and fast rules for network categorization, following are a few of the more common categories of networking ... 

FMEA is simply an analysis tool that identifies all the ways a particular component can fail and what its effects would be at the subsystem level and ultimately on the system. FMEA is vastly different from fault tree analysis. Fault tree analysis is a top-down analysis of faults in a system. FMEA is a bottom-up analysis that identifies failures (not necessarily faults) in the system. The fault tree starts with the top-level or system-level concern (top event) and then works down to the events that lead to that top event. FMEA does exactly the opposite it starts with the components in the system and analyzes failures and how they impact the subsystan in which it is housed and what are the propagated effects across the syston. 

FTA is based on the premise that many of the conponent failure modes that would be studied in the FMEA technique would not contribute to any system failure. FTA is a top-down analysis of the system failures. First, the catastrophic system failures to be avoided are identified. Then contributing failures of subsystems and individual conponents are considered. FTA is widely used in the nuclear power industry, where catastrophic system failures are clearly defined. 

Such decomposition and the consolidation in the system integration (allocation of multiple functions to one element and the development of new common functions) will have to be necessary in all system levels since only limited resources can be provided in the systems. Here we speak of a top down analysis, which later... 

Jamshidi, N. and B. 0. Palsson 2008. Top-down analysis of temporal hierarchy in biochemical reaction networks. PLoS Comput Biol 4(9) el000177. 

Wolfe et al. [43] extended and modified the Feature Integration Theory proposing that visual search is executed in a subconscious bottom-up and a conscious top-down process at the same time. During the bottom-up analysis, all salient items are subconsciously pushed into the focus of attention (similar to the conjunction search for a single distinctive feature). A second conscious top-down analysis steers the viewer s attention towards the most promising features hy applying a prior to the search. 

H.2 A Systematic Procedure for Plantwide Control System Design H.2.1 Control System Design Objectives H.2.2 Top-Down Analysis H.2.3 Bottom-Up Design... 

H.3.1 Step I Specify the Control System Design Objectives H.3.2 Step II Perform a Top-Down Analysis H.3.3 Step III Develop a Bottom-Up Design H.3.4 Step IV Validate the Proposed Control Structure... 

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