14392520
An ethnographic study of distributed problem solving in spreadsheet development
In contrast to the common view of spreadsheets as “single-user” programs, we have found that spreadsheets offer surprisingly strong support for cooperative development of a wide variety of applications. Ethnographic interviews with spreadsheet users showed that nearly all of the spreadsheets used in the work environments studied were the result of collaborative work by people with different levels of programming and domain expertise. Cooperation among spreadsheet users was spontaneous and casual; users activated existing informal social networks to initiate collaboration.
1650301
The spreadsheet interface: A basis for end user programming
749339
Using the genetic algorithm to find snake-in-the-box codes
Genetic Algorithms are heuristic search schemes based on a model of Darwinian evolution. Although not guaranteed to find the optimal solution, genetic algorithms have been shown to be effective at finding near optimal and, in some cases, optimal solutions to combinatorially explosive problems. Finding a maximal length snake, a list of vertices satisfying specific constraints, in an n -dimensional hypercube, the "box", is the type of problem that suffers from (serious) combinatorial explosion. That is, as n increases, the size of the solution space that must be searched increases very rapidly. As a consequence, the maximum lengths of snakes have previously only been determined for n ≤ 6. Since their identification in the late 1950’s, snakes (also known as Snake-In-The-Box codes) have received a significant amount of research attention. Snake-In-TheBox codes have a variety of applications in areas such as error-detection in analog-to-digital conversion, electronic combination locking schemes, and disjunctive normal form simplification. Given a certain dimension for a hypercube, the longer the snake or list of codewords, the more useful it is in the application. In this paper, we discuss experiments conducted to find snakes in hypercubes of dimension 7 and 8. To date, we have broken the previous world record for the lower bound in dimension 7 and in dimension 8 using our Genetic Algorithm approach.
52857539
Computer graphics
11759806
Structural and biophysical mechanisms underlying dynamic sensitivity of primary sensory interneurons in the cricket cercal sensory system
Abstract We constructed probabilistic models of afferent inputs and compartmental models of interneurons in the cricket cercal system to examine the effects of dendritic morphology, distribution of synaptic inputs, and membrane properties on interneuron directional tuning properties. The mean directional tuning of afferent inputs to an interneuron was an excellent predictor of its directional tuning. Location of the synapses on the interneurons’ dendrites was not essential to determining tuning characteristics, but had a substantial effect on sensitivity. Thus, we conclude that both sampling of the afferent population, and anatomical distribution of synaptic inputs are important determinants of an interneuron's directional response.
3221324
How common random numbers affect multinomial selection
We consider the effect of common random numbers (CRNs) among simulated systems in two different multinomial selection procedures: the classical procedure BEM (Bechhofer, Elmaghraby, and Morse) and procedure AVC (all vector comparisons). CVe examine a simple two population scenario and demonstrate analytically how CRNs affect the probability of correct selection (PCS). In addition, various levels of positive correlation are induced to approximate the effect of using CRNs with complex simulated systems. We present analytical and simulation results to show the effect correlation has on the probability of correct selection (PCS) for each solution procedure. This paper responds to Jim Wilson’s question raised at WSC’96 about how the use of CRNs affects multinomial selection procedures.
2346213
Healthcare Enterprise Process Development and Integration
Healthcare enterprises involve complex processes that span diverse groups and organisations. These processes involve clinical and administrative tasks, large volumes of data, and large numbers of patients and personnel. The tasks can be performed either by humans or by automated systems. In the latter case, the tasks are supported by a variety of software applications and information systems which are very often heterogeneous, autonomous, and distributed. The development of systems to manage and automate these processes has increasingly played an important role in improving the efficiency of healthcare enterprises. In this paper we look at four healthcare and medical applications that involve investigative, clinical, and administrative functions. Based on these applications, we derive the requirements for developing enterprise applications that involve the coordination of a variety of tasks performed by humans, information systems, and legacy applications.