Abstract: A control system for the manufacture of small-order-quantity goods. A network of events, activities and baseline schedule dates is constructed. Availability of external components and actual internal progress are measured by a slack variable. Optimization is based on use of the slack variable for allocation of resources. Critical items are determined rapidly and in parallel. Cost estimation of schedule improvements are readily determined.

Abstract: An adjustable inclination reading/writing board for attachment to a table or desk top. A single operating lever disengages a support member from base strip members on the table top, allowing the inclination of the planar board member to be adjusted.

Abstract: A solar trough reflector structure using a single stressed reflector skin, parabolic shaped ribs, and members to structurally close the aperture develops high strength and stiffness from a minimum of material.

Abstract: In an asphalt mixing plant, a portion of the heat used to vaporize water in the process of drying aggregate is recovered by conducting dryer exhaust gases through parallel ducts which extend serially through the aggregate cold feed bins. These parallel ducts are vertically elongated for optimum heat transfer and to avoid impeding aggregated flow. The ducts have vertically extending external fins for greater contact with the aggregate in the bins. They also have horizontally extending internal fins for improved heat transfer between the exhaust gases and the ducts. The ducts are peaked, and conforming protective caps are provided to prevent damage to the ducts during loading of the bins. Water injection is used to initiate condensation of water vapor in the exhaust gases.

Abstract: Apparatus is disclosed for converting solar energy to more useful forms, i.e., thermal and electrical energy. Such apparatus includes a photoelectric transducer (e.g., an array of photovoltaic cells), means for concentrating solar energy on the transducer, and means for circulating a liquid between the transducer and the solar energy concentrator. The spectral properties of the liquid are such that the liquid functions as a bandpass filter, transmitting solar energy to which the transducer is responsive and absorbing solar energy to which the transducer is non-responsive. The transmitted solar energy is converted to electrical energy by the transducer, and the absorbed solar energy is converted to heat by the liquid. Preferably, the liquid is circulated through a container which, in the vicinity of the transducer, is constructed so as to provide optical gain to the system and to integrate incident solar energy for the purpose of eliminating "hot spots" which could overheat, and thereby damage, the transducer.

Abstract: Spherically-shaped dish and cylindrically-shaped trough reflectors are produced by the deflection of a thin reflective element within its elastic range of stress. A spherical or cylindrical shape is produced by including a pure bending moment stress pattern in the reflective element. This is accomplished by clamping the edges of the reflective element to a rigid frame which is precisely dimensioned relative to the dimensions of the reflective element. Preferably, the surface of the frame which engages and supports the reflective element is tangent to the desired radius of curvature of the reflector. Close control of the dimensions insures that no compressive or tensile stresses are induced in the element by forces from the support surfaces, such forces tending to push the edges of the reflective element toward or away from each other.