Software discussion

This is the first chapter that includes problems involving molecular modeling software. Discussion of such software is beyond the scope of this text E. G. Lewars, Computational Chemistry, 2nd ed.. Springer, New York, 2011 provides a readable introduction to the theory and applications of molecular modeling. In addition, examples of uses of molecular modeling in chemistry curricula are discussed in L. E. Johnson, T. Engel, J. Chem. Educ., 2011, 88, 569 and references cited therein. 

While it is relatively easy to outhne the functionahty and unique aspects of the software discussed above, it is a great deal harder to describe the level of difficulty required to achieve a desired end result and to characterize how weU functions are performed. Online help systems, multimedia components, associated software development tools, improved parameter measurement tools, and higher-fidelity models will no doubt impact these aspects. 

In reviewing software developed in association with nuclear science and technology programs, or directed to the solution of research and engineering problems in the nuclear field, one is struck with the pervasiveness of these efforts. The software discussion up to this point has been concerned with developments which are generally regarded as systems software, as opposed to applications. The final section of this software review takes a look at selected computer-based applications. The intent is not to describe software developed for the solution of specific reactor physics, nuclear science and... 

A partial list of forecasting software discussed by Yurkiewicz (2012) is given below ... 

A generalization of this example to multi-well and multi-channel systems is straightforward and easily implemented in kinetic software (discussed later). All integrals are replaced by finite sums and energy graining will be one important input parameter to such codes. 

Most of the software discussed in previous chapters performs different measurements internally to calculate the likelihood of malignancy or suspicion. This value is needed to decide by threshold whether or not a finding should be pointed out to the user. Normally, the value itself is not given to the user. In some programs, the color or size of a marker indicates the level of suspicion. 

There has been considerable discussion about whether computer-based learning offers substantial advantages over any other method. There has been very little evidence in the literature of pedagogically successful software. Is there a sense in which the MBL software discussed in this paper could be considered pedagogically successful This paper has shown... 

Defects or faults in any component of the loop can develop into malfunctions. Faults are not always visible to the operator immediately, but may appear in such a way that they give rise to complete loop failure. In safety-critical applications, no failure can be tolerated [3]. Redundancies in hardware and software facilitate fault recovery. So, for increased dependability fault tolerant control (PTC) is an ideal solution. In critical controls it may be disastrous to tolerate any failure of control systems. In PTC the system continues to operate with single failure in components and/or subsystems. Also in cases of critical controls, FTC will make a controlled shutdown to a safe state in a critical situation. FTC systems use the help of redundancies in hardware and software, discussed earlier, and fault diagnostics and intelligent software to monitor health and behavior of components and function blocks and take remedial action. With these tools the faults are isolated and suitable... 

We are now in a position to express -r as a function of X and use the techniques in Chapter 2. However, we will use a better method to solw CRE problems, namely the Polymath software, discussed in the next chapter... 

Saboo, A. K., Morari, M., and Colberg, R. D., RESHEX An Interactive Software Package for the Synthesis and Analysis of Resilient Heat Exchanger Networks II. Discussion of Area Targeting and Network Synthesis Algorithms, Computers Chem. Eng., 10 591, 1986. 

The other parameters used in the calculation of STOMP and GIIP have been discussed in Section 5.4 (Data Interpretation). The formation volume factors (B and Bg) were introduced in Section 5.2 (Reservoir Fluids). We can therefore proceed to the quick and easy deterministic method most frequently used to obtain a volumetric estimate. It can be done on paper or by using available software. The latter is only reliable if the software is constrained by the geological reservoir model. 

Projection radiography is widely used for pipe inspection and corrosion monitoring. Film digitisation allows a direct access to the local density variations by computer software. Following to a calibration step an interactive estimation of local wall thickness change based on the obtained density variation is possible. The theoretical model is discussed, the limitations of the application range are shown and examples of the practical use are given. The accuracy of this method is compared to results from wall thickness measurements with ultrasonic devices. 

The manuals accompanying some software packages discuss the efficiency of... 

Simplex optimizations have been tried in the past. These do not assume a quadratic surface, but require far more computer time and thus are seldom incorporated in commercial software. Due to the unavailability of this method to most researchers, it will not be discussed further here. 

The manuals accompanying many software packages contain discussions of how to handle convergence difficulties. 

This appendix is not intended to provide a comprehensive listing of computational chemistry software packages. Some of the software packages listed here are included because they are very widely used. Others are included because they pertained to topics discussed in this book. A few relevant pieces of software were omitted because we were not able to obtain an evaluation copy prior to publication. 

Some of these software packages also have semiempirical or molecular mechanics functionality. However, the primary strength of each is ah initio calculation. There are also ah initio programs bundled with the Unichem, Spartan, and Hyperchem products discussed previously in this appendix. 

Image Files. Only the physical problem of moving or storing files has been discussed herein. The format in which the data is actually stored or transmitted is another part of the process. There are a number of file formats, many of which are proprietary, developed to suit the needs of a particular computer platform or software appHcation. There has been some effort to standardize to a few file types, but many others are in use. A thorough discussion of graphics file formats is available (20). 

The Software Dtrecto, pubhshed by the American Institute of Chemical Engineers as a supplement to the journal Chemtca/EngmeenngProgress, shows the scope of computer utilisation in chemical technology. Selection and evaluation of available software packages have been discussed (4). The topics covered in the second annual directory (Oct. 1990) include ... 

Rigorous error bounds are discussed for linear ordinary differential equations solved with the finite difference method by Isaacson and Keller (Ref. 107). Computer software exists to solve two-point boundary value problems. The IMSL routine DVCPR uses the finite difference method with a variable step size (Ref. 247). Finlayson (Ref. 106) gives FDRXN for reaction problems. 

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