FATRAM-A Core Efficient Cut-Set Algorithm

Many algorithms have been developed for determining minimal cut sets for logic models (in particular, fault trees). Although these methods are theoretically correct, computer implementation of these algorithms proves them less efficient than is desirable. This paper presents a new method for determining the minimal cut sets, which makes more efficient use of computer memory. The gates are resolved in a deterministic manner according to the following rules: 1) AND gates and OR gates with gate inputs are resolved; and 2) OR gates with only basic event inputs are resolved last. Other computer techniques provide increased efficiency for implementing this method. The FATRAM algorithm for finding minimal cut sets for fault trees does use computer core memory effectively. The use of stacks (last-in first-out arrays) for the AND and OR gates has also increased the efficiency of the program. The use of dynamic storage makes the program more flexible.     

Infrared television recording and measurement of ocular behavior in the human infant.

Considers the variables of eye position, eye movements, pupillary dilation, and extent of eyelid opening in the method of closed circuit television (CCTV). New and relatively inexpensive devices are described for making CCTV more feasible for recording behavioral activity. The recording, displaying, and measuring of the images are described and exemplified. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The self-concept: Fact or artifact.

Research interest in the last 10 years has been sufficient enough so that it is now possible to ask whether the self is an objective reality or a nebulous abstraction. Assessment of the emipircal and theoretical foundations as well as the philosophical suggest that the self is an artifact which has been invented to explain experience. From Psyc Abstracts 36:01:3HJ25L. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The fracture of rubber-modified polystyrene

This paper reports a successful attempt to apply the theories of fracture mechanics to the failure of impact polystyrene in air. The results show that linear elastic fracture mechanics is limited to correlating crack initiation data but that both maximum load and initiation data can be correlated using a constant crack opening displacement criterion calculated from the Dugdale model. The results are supported by similar calculations made from experiments with two other commercially important plastics: PVC and polycarbonate. The toughness of these materials and that of PMMA, polystyrene, and poly(ethylene terephthalate) are compared in terms of Rice's contour integral, J.     

Measurement of oxidation stability of polyolefins by thermal analysis

Differential thermal analysis (DTA) is well known for measuring temperatures and heats of physical and chemical transitions in materials. Recent development work on improved stabilization systems for polyolefin wire insulations has required fast procedures for measuring the performance of stabilization systems. Isothermal DTA procedures have been developed into routine tools for measuring stability of polyolefins by determining the oxidative induction time at elevated temperatures. Oxidative induction time has been used to study the stability of polyethylene and polypropylene in raw material form and on wire. The dependence on temperature and antioxidant concentration have been measured. Effects of oxidation catalysts, catalyst deactivators and various environmental exposures are readily observed. Techniques and apparatus have been developed for simultaneous testing of a multiplicity of samples, providing for economical large scale use of the method.     

The influence of specimen size and mode of loading on the fracture of graphite

Predictions of graphite strength under tensile and bending loads using fracture mechanics have been compared with experimental data and the currently used Weibull method. The methods are comparable for similar specimens but Weibull's method fails to predict the observed effects for large specimen size differences. Discussion of this failure indicates that the basis of Weibull's theory (a volumetric flaw distribution) may be inapplicable to failure of materials resulting from surface defects. Examination of graphite rods has shown a defect size distribution across the material which leads to prediction of lower strengths for the inner rod regions with respect to the outer regions. Experimental results follow the predicted trend but it is considered that further examination of the fracture mechanics technique must be undertaken before it can be recommended as a design method for graphite materials.     

Thin film thickness monitor shutter

This article describes a simple electronic dual-activated shutter which is designed to interface with the Sloan digital thickness monitor model DTM-200 or a set of double-pole double-throw switches which can be operated manually.     

New unidirectional transducer and broadband reflector of acoustic surface waves

An acoustic-surface-wave multistrip coupler, formed into the shape of a U, may be used on materials of high electro-mechanical coupling coefficient to convert a bidirectional interdigital transducer into a unidirectional transducer with negligible loss of bandwidth. The U-shaped coupler by itself acts as a normal-incidence mirror, and can have a reflection loss of less than 2 dB over a 60% bandwidth. Both devices are constructed of evaporated aluminium by existing photolithographic techiques. No special polishing operations or extra electrical components are required.