Vigorous plant growth without sunlight is routinely achieved in commercial hydroponic lettuce and tomato production using electric lamps. This same technology can be used to maintain live turf grass in closed athletic stadiums. It can also be used to supplement natural sunlight in retractable roof stadiums. The challenge is to determine the optimal combination of genetic characteristics and env...

An automaton A is called a retractable automaton if, for every subau-tomaton B of A, there is at least one homomorphism of A onto B which leaves the elements of B fixed (such homomorphism is called a retract ho-momorphism of A onto B). We say that a retractable automaton A=(A,X,δ) is Boolean-type if there exists a family {λ B | B is a subautomaton of A} of retract homomorphisms λ B of A such th...

Retractable type fall arresters constitute a most effective group of components used in personal protection systems protecting against falls from a height. They are designed primarily for outdoor use, which results in exposure to atmospheric factors associated with risk of corrosion of metal elements. This paper presents the results of a study, in which retractable type fall arresters were expo...

In calculi for modelling communication protocols, internal and external choices play dual roles. Two external choices can be viewed naturally as dual too, as they represent an agreement between the communicating parties. If the interaction fails, the past agreements are good candidates as points where to roll back, in order to take a different agreement. We propose a variant of contracts with s...

Retractable type fall arresters are very effective personal equipment protecting against falls from a height. These devices are used under different atmospheric conditions and in the presence of various types of industrial pollution. For this reason appropriate locking after conditioning simulating extreme conditions of a worksite is one of the essential characteristics of retractable type fall...

DoEpi is a series of computer exercises and a framework for making new exercises based on the Epi Info programs for epidemiologic computing. The system contains three outbreak investigations, a research survey, four exercises in advanced Epi Info programming, and four exercises in public health surveillance. The exercises are available via the Internet (www.cdc.gov, under "Publications, Product...

j This paper presents a new concept for retractable roof structures. The new structures consist of a foldable lattice of beams connected by cylindrical joints, to which covering panels or membranes are attached. These structures fold towards their perimeter and there is practically no limit to their shape. Solutions to the key problems that have to be solved in the course of the kinematic desig...

Recent years have witnessed a growing interest in developing personalized and nonhospital based care systems to improve the management of cardiac care. The EPI-MEDICS project has designed an intelligent, portable Personal ECG Monitor (PEM) embedding an advanced decision making system. We present two of the ambient intelligence models embedded in the PEM: the neural-network based ischemia detect...