An algorithm for the traveling salesman problem with pickup and delivery customers

The paper extends the branch and bound algorithm of Little, Murty, Sweeney, and Karel to the traveling salesman problem with pickup and delivery customers, where each pickup customer is required to be visited before its associated delivery customer. The problems considered include single and multiple vehicle cases as well as infinite and finite capacity cases. Computational results are reported.     

Integral transforms for shock-shock interaction — Three dimensional planar wings

Résumé Si une onde de choc de force arbitraire rencontre une aile pointue aplatie qui se déplace à une vitesse supersonique, une région de perturbations est générée. Une expression analytique explicite en termes de perturbations de pression est trouvée par l'application de transformations d'intégrales au problème des conditions initiales-limites. La théorie est appliquée au problème de l'interaction d'une onde de choc plane et d'une aile delta plane (avec des bords d'attaque définiment supersoniques) en petite incidence. Les résultats numériques pour la répartition des pressions sont présentés.     

Rate constants for quenching of O2(1Δg) with sulfur compounds

The rate constants for the quenching of O₂(¹Δ_g) with carbon disulfide, dimethyl sulfide, dimethyl disulfide, diallyl disulfide, ethyl mercaptan, and thiophene have been determined in a discharge flow system in the absence of oxygen atoms. The rate constants are found to be (6.5 ± 0.6) × 10⁴, (1.8 ± 0.2) × 10⁴, and (3.5 ± 0.6) × 10³ L/mol · s for dimethyl sulfide, ethyl mercaptan, and thiophene, respectively. The other compounds have rate constants <9.9 × 10² L/mol · s. In the case of dimethyl sulfide, even when NO₂ concentration is more than what is required to remove oxygen atoms completely, the rate constants are found to vary with different amounts of NO₂. No correlation is found to exist between the logarithm of the rate constants and the ionization potentials of the compounds.     

A steepest-descent method for optimization of mechanical systems

Steepest-descent optimal control techniques have been used extensively for dynamic systems in one independent variable and with a full set of initial conditions. This paper presents an extension of the steepest-descent technique to mechanical design problems that are described by boundary-value problems with one or more independent variables. The method is illustrated by solving finite-dimensional problems, problems with distribution of design over one space dimension, and problems with distribution of design over two space dimensions.     

Power Reflection,Transmission and Absorption Coefficients for a Mobile Collisional Magneto Plasma Slab

Coefficients of power reflection (R), transmission (T) and absorption (A) for a homogeneous, magnetised, collisional and moving plasma slab are derived and discussed by taking p-polarized wave as the e.m. source wave and without imposing any restriction on the slab velocity. Effects of electron-neutral collisions (ν_en), ion-neutral collisions (ν_in) and the external magnetic field are included through momentum transfer equations. Plasma slab velocity (β = ν/c), electron ion densities (ω_pe,i/ω) and the collision frequencies (ν_en,in) are found to cause significant change in the values of R, T and A, a numerical study of which is illustrated in the paper.