Behavioral synthesis transformations

The goals of background memory management (BMM) are to minimize background memory (arrays in the HardwareC specification) both in number and size as much as possible, and to simplify address generation taking into ac- 

Frequently, only a small window of an array is used in a loop iteration to compute the next entry. A typical expression is the statement a[i] = a[i-l] + 3 a[i-2] located within a large loop with index i If that array is not used for other computations, the whole structure can be pushed into foreground. 

All array indices are analyzed over time through a fast simulation to support the above-mentioned steps. This information will also be used for actual array-type selection. For the investigated applications, arrays could be realized through FIFOs or ring buffers in most cases. If possible, array entries will be moved to other locations to realize monotonous access orders supporting such efficient realizations. A fast and very simple list scheduler is used to estimate background memory access conflicts, 

As already mentioned earlier, the combustion engine control algorithm is an excellent test vehicle for behavioral transformations, especially since the background memory is both complex and intricate. The initial HardwareC specification uses 37 arrays of 128 float values each. After background memory 

The partitioning is based on the mobility P op) of operations, which is limited through ASAP- and ALAP-scheduling. A probability p(op,t) can be associated with each operation, indicating the probability that operation op will finally be found in clock cycle t If an operation op has, for example, the mobility P op) = 3 then it is assumed that it will be finally scheduled with a probability of p op,t) = I into clock cycle t, ASAP op) t ALAP op). To estimate the distribution of all hardware resources, the probability of a single operation type can be summed up within a clock cycle to derive the so-called distribution graph D  

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As a first step, the HardwareC compiler performs a profound data/control-flow analysis. A DFG optimizer is directly coupled to the compiler. After optimization, the data/control-fiow graph will be stored as a combined single flow graph which can be considered as a data base. All behavioral synthesis transformations require input from this data base and will produce output in the graph format defined in chapter 2. 

Be is the expected behavior of the system, specifically the set of variables showing how the system should work. Be is set according to requirements and functions 2. Pre-synthesis transforms the fimetiraial aichiteeture of the system (F) into a gentaic structure (GS) using abstract (ugans ... 

After behavioral synthesis, a transformed and optimized flow graph is available, which still does not include any explicit structural information (except module-type proposals for background memory and constraints specified in the input description). The goal of the consecutive structural synthesis process is to transform this flow graph information into an actual implementation that can be executed on the ASIC emulator board. The main steps to be carried out are scheduling, allocation, and binding. The results will again be illustrated by means of the DHRC-benchmark. 

Abstract In this paper, the discovery and synthesis of the explosive l,l-diamino-2,2-dinitroethene (FOX-7) are described, together with an account of its structural, spectroscopic, and explosive properties. The chemical reactivity of FOX-7 towards nucleophilic substitution (transamination), electrophilic substitution, and acid-base properties is explored, as is its thermal behavior (phase transformations and thermal decomposition). The molecular structure and physical properties of FOX-7 are compared with those of its three isomers (as yet unsynthesized), as derived by theoretical calculations. Finally, the physical properties of FOX-7 are compared to those of various energetic molecules that are structurally related to FOX-7. 

R. Camposano, Behavior-Preserving Transformations for High-Level Synthesis , Proc. Workshop on Hardware Specification, Verification, and Synthesis Mathematical Aspects, Springer-Verlag, 1989. 

The Hercules system provides an integrated environment for the behavioral synthesis and optimization of hardware behavior. It performs both user-driven and automatic behavioral transformations, and produces as output one or more sequencing graph abstractions of the optimized behavior, described in SIF. The flow of operation in Hercules is described below. 

It is apparent that the use of enzymatic catalysis continues to grow Greater availabiUty of enzymes, development of new methodologies for thek utilization, investigation of enzymatic behavior in nonconventional environments, and the design and synthesis of new biocatalysts with altered selectivity and increased stabiUty are essential for the successhil development of this field. As more is learned about selectivity of enzymes toward unnatural substrates, the choice of an enzyme for a particular transformation will become easier to predict. It should simplify a search for an appropriate catalyst and help to estabhsh biocatalytic procedures as a usehil supplement to classical organic synthesis. 

The significance of these metabolites in the biosynthesis of the thiamine thiazole in considered next. Although, from their constitution, and from the tracer experiments, the metabolites are undoubtedly the products of transformation of 1-deoxy-D-t/ireo-pentulose, their significance in the biosynthesis of the thiazole of thiamine is not clear. The thiazole glycol is not a product arising from a transformation of the thiazole (5) of thiamine. Reduction to this thiazole (5) occurs in dialyzed extracts of disrupted cells, in the presence of ATP, NADH, and NADPH, but only at 0.2% the rate of synthesis of the thiamine thiazole (5) by intact cells. The behavior of the thiazole glycol on plates is merely a consequence of the extreme sensitivity of the tetrazolium reagent. 

All chiral products as well as enantiomerically enriched substrate ketones from such transformations are valuable building blocks in asymmetric synthesis [182,183]. While CHMO-type enzymes in general display such a behavior, CPMO-type biocatalysts give... 

V-Sb-oxide based catalysts show interesting catal)dic properties in the direct synthesis of acrylonitrile from propane [1,2], a new alternative option to the commercial process starting from propylene. However, further improvement of the selectivity to acrylonitrile would strengthen interest in the process. Optimization of the behavior of Sb-V-oxide catalysts requires a thorough analysis of the relationship between structural/surface characteristics and catalytic properties. Various studies have been reported on the analysis of this relationship [3-8] and on the reaction kinetics [9,10], but little attention has been given to the study of the surface reactivity of V-Sb-oxide in the transformation of possible intermediates and on the identification of the sxirface mechanism of reaction. 

The preparation and investigation of the thietane oxide system (5a) is largely associated with stereochemical and conformational studies . The investigation of the thietane dioxides (5b) is substantially related to the chemistry of sulfenes , the [2 -I- 2] cycloaddition of which with enamines is probably the method of choice for the synthesis of 5b . The study of the thiete dioxide system (6) evolved, at least in part, from the recognition that the unstable thiete system 183 can be uniquely stabilized when the sulfur in the system is transformed into the corresponding sulfone , and that the thiete dioxide system is very useful in cycloadditions and thermolytic reactions. The main interest in the dithietane oxides and dioxides (7) appears to lie in the synthetic challenge associated with their preparation, as well as in their unique structural features and chemical behavior under thermolytic conditions . ... 

One of the cornerstones of combinatorial synthesis has been the development of solid-phase organic synthesis (SPOS) based on the original Merrifield method for peptide preparation [19]. Because transformations on insoluble polymer supports should enable chemical reactions to be driven to completion and enable simple product purification by filtration, combinatorial chemistry has been primarily performed by SPOS [19-23], Nonetheless, solid-phase synthesis has several shortcomings, because of the nature of heterogeneous reaction conditions. Nonlinear kinetic behavior, slow reaction, solvation problems, and degradation of the polymer support, because of the long reactions, are some of the problems typically experienced in SPOS. It is, therefore, not surprising that the first applications of microwave-assisted solid-phase synthesis were reported as early 1992 [24],... 

Recent research on aminocarbenes has led to the development of a very fruitful field. The synthesis of relevant complexes (Scheme 19) such as aminobis(yhde) carbene species (69) [147], cyclic C-amino P-ylides (70) (easily transformed into carbenes) [148] and their corresponding complexes (71) [149], and special ylides (72), which also transform very easily into carbenes by loss of pyridinium group, has been reported. Emphasis has been made on the transformation between ylides and carbenes and on the donor properties of the ylides. From the results obtained the ylides have shown a stronger a-donor behavior compared with the carbenes. 

Alkaline earth metal oxides have been used as solid base catalysts for a variety of organic transformations. Excellent reviews by Tanabe 4) and Hattori 2,3,7) provide detailed information about the catalytic behavior of alkaline earth metal oxides for several organic reactions of importance for industrial organic synthesis. In this section, we describe in detail reactions that have been reported recently to be catalyzed by alkaline earth metal oxides. 

For the very low density varieties of the cases shown in Figure 2 and, more particularly, Figure 4 (curve 7), for which initiation is slow compared to both termination (release from end of template) and polymerization, a simpler treatment, in which the interference of one ribosome with another is totally neglected, should suffice. In this case an equation of the form of Eq. (1), herein only applied to the problem of DNA synthesis, should be valid, but Eqs. (2) and (3) should be modified to account for repetitive initiation at site 1 and continuing release from site K, respectively Eqs. (4) and (6) will not apply. In the even more restricted (but perhaps biochemically relevant) case in which, in addition to neglecting ribosome interference, one may also neglect the back reaction (kb x 0), one may solve this system of equations (Eq. (1), plus Eqs. (2) and (3) modified as described) very easily by taking Laplace transforms.13 This is the only case with repetitive initiation for which we have been able to find solutions for the transient, as well as steady state, behavior. 

The three-component method is applicable to the synthesis of various C(6)- or C(7)-functionalized PGs. Scheme 11 illustrates the tandem conjugate addition-aldol reaction that affords 7-hydroxy-PGE derivatives (18). Both saturated and unsaturated C7 aldehydes can be used as a side-chain units. The aldol adducts can be transformed to naturally occurring PGs (5a, 19) and, more importantly, to a variety of analogues such as tumor-suppressing A7-PGA, (20) or 7-fluoro-PGI2, a stabilized prostacyclin (21). The unique cellular behavior displayed by A7-PGA methyl ester is well correlated to its chemical reaction with thiols (20). 

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