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121.
Quantifying the complexity of systems consisting of many interacting parts has been an important challenge in the field of complex systems in both abstract and applied contexts. One approach, the complexity profile, is a measure of the information to describe a system as a function of the scale at which it is observed. We present a new formulation of the complexity profile, which expands its possible application to high‐dimensional real‐world and mathematically defined systems. The new method is constructed from the pairwise dependencies between components of the system. The pairwise approach may serve as both a formulation in its own right and a computationally feasible approximation to the original complexity profile. We compare it to the original complexity profile by giving cases where they are equivalent, proving properties common to both methods, and demonstrating where they differ. Both formulations satisfy linear superposition for unrelated systems and conservation of total degrees of freedom (sum rule). The new pairwise formulation is also a monotonically nonincreasing function of scale. Furthermore, we show that the new formulation defines a class of related complexity profile functions for a given system, demonstrating the generality of the formalism. © 2013 Wiley Periodicals, Inc. Complexity 18:20–27, 2013 相似文献
122.
Harmon RS DeLucia FC LaPointe A Winkel RJ Miziolek AW 《Analytical and bioanalytical chemistry》2006,385(6):1140-1148
The concept of utilizing laser-induced breakdown spectroscopy (LIBS) technology for landmine detection and discrimination
has been evaluated using both laboratory LIBS and a prototype man-portable LIBS systems. LIBS spectra were collected for a
suite of landmine casings, non-mine plastic materials, and ‘clutter-type’ objects likely to be present in the soil of a conflict
area or a former conflict area. Landmine casings examined included a broad selection of anti-personnel and anti-tank mines
from different countries of manufacture. Other materials analyzed included rocks and soil, metal objects, cellulose materials,
and different types of plastics. Two ‘blind’ laboratory tests were conducted in which 100 broadband LIBS spectra were obtained
for a mixed suite of landmine casings and clutter objects and compared with a previously-assembled spectral reference library.
Using a linear correlation approach, ‘mine/no mine’ determinations were correctly made for more than 90% of the samples in
both tests. A similar test using a prototype man-portable LIBS system yielded an analogous result, validating the concept
of using LIBS for landmine detection and discrimination. 相似文献
123.
124.
J. Zarestky C. Stassis B.N. Harmon J.A. Begum R.M. Moon S.H. Liu D.D. Koelling 《Journal of magnetism and magnetic materials》1983,38(1):61-66
Polarized neutron scattering techniques have been used to study the spatial distribution of the magnetization induced in a single crystal of LaSn3 by a magnetic field of 42.5 kG at 100 K. We find that the magnetic form factor decreases very rapidly with increasing scattering angle, and bears no resemblance to the spin or orbital free-atom magnetic form factor. The experimental results are in reasonable agreement with band theoretical calculations of the spin magnetic form factor of LaSn3. We conclude that (a) the spin part is the dominant contribution to the bulk susceptibility of LaSn3 and (b) there is a substantial amount of Sn-5p electronic character in the wavefunctions near the Fermi level. 相似文献
125.
126.
Choline chloride forms two lower hydrates — a dihydrate and a monohydrate — with quite unusual properties. The dihydrate is a highly structured liquid salt; the IR spectrum is similar to that of a crystalline framework clathrate hydrate, and there are separate 1H-NMR signals for the cation hydroxyl and water protons. The dihydrate is a crystalline solid at reduced pressure. The crystalline monohydrate only exists at reduced pressure; at atmospheric pressure it disproportionates to liquid dihydrate and anhydrous choline chloride. The anhydrous choline chloride thus formed is a previously unreported crystal modification of choline chloride. 相似文献
127.
Pullammanappallil P. Harmon J. Chynoweth D. P. Lyberatos G. Svoronos S. A. 《Applied biochemistry and biotechnology》1991,28(1):33-42
Applied Biochemistry and Biotechnology - Process control of anaerobic digesters is a particularly challenging problem because of the diversity of possible causes that can lead to digester... 相似文献
128.
Melvyn Rowen Churchill Stuart A. Julis R. Bruce King Claude A. Harmon 《Journal of organometallic chemistry》1977,142(3):C52-C54
The reactions of the non-alternant polycyclic aromatic hydrocarbon 3,5-dimethylaceheptylene, C14H8Me2, with various transition metal carbonyls and the molecular geometry of the compounds (C14H8Me2)Mn2(CO)6 and (C14H8Me2)Fe3(CO)8 is shown. 相似文献
129.
Elkin CD Zuccola HJ Hogle JM Joseph-McCarthy D 《Journal of computer-aided molecular design》2000,14(8):705-718
Hepatitis delta virus (HDV) encodes a single polypeptide called hepatitis delta antigen (DAg). Dimerization of DAg is required for viral replication. The structure of the dimerization region, residues 12 to 60, consists of an anti-parallel coiled coil [Zuccola et al., Structure, 6 (1998) 821]. Multiple Copy Simultaneous Searches (MCSS) of the hydrophobic core region formed by the bend in the helix of one monomer of this structure were carried out for many diverse functional groups. Six critical interaction sites were identified. The Protein Data Bank was searched for backbone templates to use in the subsequent design process by matching to these sites. A 14 residue helix expected to bind to the d-isomer of the target structure was selected as the template. Over 200000 mutant sequences of this peptide were generated based on the MCSS results. A secondary structure prediction algorithm was used to screen all sequences, and in general only those that were predicted to be highly helical were retained. Approximately 100 of these 14-mers were model built as d-peptides and docked with the l-isomer of the target monomer. Based on calculated interaction energies, predicted helicity, and intrahelical salt bridge patterns, a small number of peptides were selected as the most promising candidates. The ligand design approach presented here is the computational analogue of mirror image phage display. The results have been used to characterize the interactions responsible for formation of this model anti-parallel coiled coil and to suggest potential ligands to disrupt it. 相似文献
130.