Using profit maximizing scheduling models to structure operational trade-offs and manufacturing strategy issues

Manufacturing plays an increasingly important role in determining the competitiveness of the firm. However, corporate strategy is often formulated with little regard for how these decisions affect operations within the manufacturing system. Detailed models provide a necessary link between manufacturing performance and the functional policies followed by the firm, so that the strengths of the manufacturing system can be consistently reflected in strategic decisions.This paper presents a scheduling model that relates the strategic decisions that determine the type of work that must ultimately be processed by the manufacturing system with the detailed decisions that determine how this work should be scheduled. The model accounts for varying processing time, delay penalty, and revenue characteristics among the jobs available for processing by a single facility, with jobs partitioned in multiple classes such that a setup is incurred each time two jobs of different classes are processed in succession. Given limited processing capacity, the objective is to simultaneously determine the subset of jobs to accept for processing and the associated order in which accepted jobs should be sequenced to maximize the total profit realized by the facility. Problem formulations and dynamic programming algorithms are presented for both the special case in which all available work is from a single job class, and the more general case involving multiple job classes. The insight derived from these models concerning the operational implications of strategic decisions is illustrated through a series of example problems, first focusing on the coordination of marketing and manufacturing policy, and finally by considering important issues related to manufacturing focus.     

Statistical inference and quantum mechanical measurement

We analyze the quantum mechanical measuring process from the standpoint of information theory. Statistical inference is used in order to define the most likely state of the measured system that is compatible with the readings of the measuring instrument and the a priori information about the correlations between the system and the instrument. This approach has the advantage that no reference to the time evolution of the combined system need be made. It must, however, be emphasized that the result is to be interpreted as the statistically inferred state of the original system rather than the state of the system after measurement. The phenomenon of “reduction of states” appears in this light as a consequence of incomplete information rather than the physical interaction between measured system and measuring instrument.     

Spontaneous staggered polarization of theF-model

The order parameter of the two-dimensionalF-model, namely the spontaneous staggered polarizationP ₀, is derived exactly. At the critical temperatureP ₀ has an essential singularity, bothP ₀ and all its derivatives with respect to temperature vanishing.     

THE ACTION SPECTRA OF FREE RADICALS PRODUCED BY THE IRRADIATION OF KERATIN CONTAINING BOUND IRON(III) IONS

Abstract—The action spectra have been determined for two free radical species produced by irradiating wool protein containing bound iron(III) ions with light between 330 and 540 nm. The faster growing free radical displays an action spectrum with a peak at 405–415 nm. It is suggested that an iron (III) ion-sulphur complex is the chromophore responsible for the formation of this carbon type radical.     

Proton capture by 15N at stellar energies

Excitation functions of the ¹⁵N(p, γ)¹⁶O proton capture reaction have been obtained at θ_γ = 45° and E_p = 150–2500 keV. Below E_p = 400 keV, the reaction is dominated by capture into the ground state of ¹⁶O. The observed excitation function for the latter process can be explained if, in addition to the two well-known J^π = 1^? resonances at E_p = 338 and 1028 keV, a direct radiative capture process (DC → 0) is included in the analysis. The direct capture component in the capture reaction is enhanced through interference effects on the tails of the two resonances. From the observed direct capture cross section, a single-particle spectroscopic factor of C²S(1p) = 1.8 ± 0.4 has been deduced for the ground state in ¹⁶O. The extrapolated astrophysical S-factor of S(0) = 64 ± 6 keV · b for the ¹⁵N(p, γ₀)¹⁶O reaction is a factor of 2.5 larger than previously reported. This result amplifies the role of the oxygen side cycle in the CNO hydrogen burning process.The observed excitation function of the ¹⁵N(p, α₁γ₁)¹²C reaction at E_p = 150 – 2500 keV shows that this reaction makes a negligible contribution to hydrogen burning at stellar energies [S(0) ≈ 0.1 keV · b] compared to ${}^{15}\text{N}\text{(}\text{p}\text{, γ}{}_0\text{)}{}^{16}\text{O and}{}^{15}\text{N}\text{(}\text{p}\text{, α}{}_{\mathrm{<mtext>o</mtext>}}\text{)}{}^{12}\text{C}$.     

The generator production of172Lu from172Hf for limited nuclear medicine research

A solvent extraction system has been developed for the separation of¹⁷²Lu from its long-lived¹⁷²Hf parent. The parent-daughter pair in equilibrium is maintained in a solution of HDEHP, and the heavy lanthanide daughter is extracted into 9M HCl. The separation factor for this generator is approximately 10⁴. The rare-earth activity so obtained is proposed for compound labelling research and animal biodistribution studies in nuclear medicine.