Bounds on the reliability of binary coherent systems

The structure function of a binary coherent system is approximated by using only a few of its minimal path sets and minimal cut sets. These two incomplete structure functions are represented as disjoint sums. The average of each is a lower and upper bound, respectively, for the system reliability. The usefulness of these bounds is demonstrated on example networks     

Component vs. system burn-in techniques for electronic equipment

Simulation can be used to determine the effects of different combinations of in-process and system burn-in times. It is shown that optimal burn-in at each stage of component assembly is not always optimal for the final system. Simulation is used to evaluate a nonrepairable system and provides individual component burn-in times that optimize the mean residual life of the assembled system     

Influence of cooking and drying processes at different temperatures on the nutritive value of the protein of mussels (Mytilus edulis)

The effect of steam cooking (96 degrees C for 15 minutes) and drying at two temperatures, 70 degrees C and 110 degrees C, on nutritive value of mussel protein was studied. The measurements were carried out by nitrogen balance techniques in growing rats, and the nutritional parameters studied were: CD, BV and NPU. The crude digestibility (CD) values were: 87 +/- 1 and 82 +/- 1, and the biological values (BV), 80 +/- 1 and 74 +/- 1 for raw mussels, dried at 70 degrees C and at 110 degrees C respectively. This implies a significant decrease in the protein nutritive values of the mussel dried at a higher temperature. Cooking prior to drying significantly improved the digestibility and the biological value of the mussel's protein. In effect, improvement was so great, that the different drying temperatures did not affect the previously cooked product in a different way; therefore, the CD (94 +/- 1 and 94 +/- 1) and the BV (90 +/- 1 and 90 +/- 2) were the same for the mussel's protein, cooked and dried at 70 degrees C or at 110 degrees C.     

Leakage of Anthocyanins from Skin of Thawed, Frozen Highbush Blueberries (Vaccinium corymbosum L.)

Factors affecting the tendency of thawed blueberries to leak pigmented exudate were investigated. Drip and anthocyanin leakage rates (ALR) were determined spectrophotometrically. Leakage vs time curves were linear or two-phase linear, ALR varying with cultivar, ripeness, and berry condition. Dewaxing increased ALR with most cultivars. ALR did not correlate with berry anthocyanin content, surface area, or cuticle thickness. ALR and amount of drip were poorly correlated. ALR varied from berry-to-berry within samples. Leakage was observed to be nonuniform on berry surfaces, appearing at skin cracks and ruptures, the calyx area, and other point sources. An hypothesis relating leakage to skin condition, fluid accumulation, and anthocyanin content is presented.     

Energy conservation in the industrial sector of developing countries

This paper begins by examining the most energy-intensive industries and methods by which fuel efficiency can be improved. Next the author analyses the economics of energy conservation using specific case studies drawn from India. It is shown that investing in energy efficiency is more economical Btu per Btu than investing in the enhancement of domestic energy resources. The author also assesses changes in the economics of conservation for private firms when there are government incentives. Finally government policies that can overcome economic and non-economic disincentives for investing in energy conservation are examined.     

Opening address: The world gas situation

Worldwide demand and supply of natural gas may rise substantially between the years 1982 and 2000, but the rate of increase will decelerate after 1990. The rapid growth of potential demand in the first decade is expected to take place in the developing countries in particular. During this period, gas production potential will rise most rapidly in Eastern Europe (including the U.S.S.R.) and in the Third World countries of Latin America, Africa, the Middle East, and Asia. In the year which has passed since the Venice Conference, forecasts of future natural gas demand in Western Europe have been reduced from 300–350 × 10⁹ m³ (in the year 2000) to 270 × 10⁹ m³. This change has greatly diminished the expected need for gas imports into Western Europe. It has also had a positive effect on the reserve position, relative to anticipated demand, of the Netherlands, which now will consider making more gas available for Western European markets.     

Worms and viruses and botnets, oh my! Rational responses to emerging Internet threats

No longer satisfied with compromising and controlling individual computers, a new breed of hackers have set their sights on virtual networks of zombie systems, which they use in concert to accomplish various nefarious deeds. Beware the botnet.