Software Reviews

Computer Science II: File Structure Charged Particles II South Dakota: An Economic and Math Simulation     

Inhomogeneous and homogeneous broadening effects onnuclear resonance experiments

Inhomogeneous broadening of resonance lines causes a reduction of absorption in nuclear resonance experiments. This is particularly devastating to the observation of the Mössbauer effect in isomers like ¹⁰⁷Ag with a half-life of 44s.It has been suggested in the literature that homogeneous broadening can provide overlap of resonance lines and thus theMössbauer effect can be recovered. The analysis presented in this paper shows that this is not the case for Mössbauer experiments, unless the radiative width Γ_Γ also increases. Although overlap occurs when the lines are homogeneously broadened to a total width Γ_{_}H which exceeds the natural width Γ, and the inhomogeneous width Δ, the Mössbauer absorption remains low because it is proportional to the factor of Γ_γ/Γ _H.     

Apparent molar volumes of crown ether complexes in several solvents at 25°C. An estimation of ionic electrostriction

The apparent molar volumes of equimolar concentrations of 18-crown-6-ether (CE) or dibenzo-18-crown-6-ether (B₂CE) and MCl (M=Na, K, or Cs) or MI in dilute solutions of anhydrous methanol, acetonitrile and dimethylsulfoxide have been calculated from density data measured at 25°C. After extrapolation to infinite dilution these results together with the apparent molar volumes of the crown ethers and the alkali metal halides were used to calculate the limiting partial molar volume change for the formation of the complexes. By noting that the charge of the complexed cation has been shown to be completely shielded from the solvent, the volume of complexation can be assumed to be a good estimation of the volume change due to electrostriction of the solvent by the cationic charge. The results are compared to the predictions of the Hepler equation.Presented at the Symposium on Electrochemistry and Spectroscopy of Solutions, Honoring Johannes Coetzee, University of Pittsburgh, November 30, 1989.On leave from Rhodes University, Grahamstown, South Africa.     

Modeling and evaluation of cyber-physical systems in civil engineering

A cyber-physical system (CPS) is a coupled system integrating computing, networking, and physical processes. Through actuation, cyber-physical systems control the physical processes, usually with feedback loops, where the physical processes affect computing and networking processes, and vice versa. In civil engineering, the most common fields of CPS applications are structural health monitoring (SHM) and structural control. A typical CPS task is the assessment of a structure based on (i) collected measurement data and (ii) a corresponding model. However, for an accurate and precise assessment of a structure, the CPS itself must be modeled and evaluated. In this paper, a conceptual modeling and evaluation approach is proposed, in which each part of a CPS is evaluated individually. In this study, the conceptual approach is presented for modeling and evaluation of CPS in civil engineering. The evaluation is based on an abstract approach allowing a discussion of a principle (i.e. general) model structure of a CPS, identifying critical issues to be studied in more detail in future research. (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Project scheduling under uncertainty and resource constraints

This paper proposes a method to improve the reliability of construction schedules by optimizing schedule robustness of construction projects. The schedule robustness is measured by a criterion evaluating the impact of deviations from the initial schedule on the makespan, which arise during the realization phase of a construction project. (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Efficient quantification of the importance of contacts for the dynamical stability of proteins

Understanding the stability of the native state and the dynamics of a protein is of great importance for all areas of biomolecular design. The efficient estimation of the influence of individual contacts between amino acids in a protein structure is a first step in the reengineering of a particular protein for technological or pharmacological purposes. At the same time, the functional annotation of molecular evolution can be facilitated by such insight. Here, we use a recently suggested, information theoretical measure in biomolecular design - the Kullback-Leibler-divergence - to quantify and therefore rank residue-residue contacts within proteins according to their overall contribution to the molecular mechanics. We implement this protocol on the basis of a reduced molecular model, which allows us to use a well-known lemma of linear algebra to speed up the computation. The increase in computational performance is around 10(1)- to 10(4)-fold. We applied the method to two proteins to illustrate the protocol and its results. We found that our method can reliably identify key residues in the molecular mechanics and the protein fold in comparison to well-known properties in the serine protease inhibitor. We found significant correlations to experimental results, e.g., dissociation constants and Φ values.