bluuebunny/crossref_metadata_2025_split huggingface dataset:
Steady-state simulation of queueing processes: survey of problems and solutions
Authors: Pawlikowski Krzysztof 
Published: July 2002

For years computer-based stochastic simulation has been a commonly used tool in the performance evaluation of various systems. Unfortunately, the results of simulation studies quite often have little credibility, since they are presented without regard to their random nature and the need for proper statistical analysis of simulation output data.This paper discusses the main factors that can affect the accuracy of stochastic simulations designed to give insight into the steady-state behavior of queuing processes. The problems of correctly starting and stopping such simulation experiments to obtain the required statistical accuracy of the results are addressed. In this survey of possible solutions, the emphasis is put on possible applications in the sequential analysis of output data, which adaptively decides about continuing a simulation experiment until the required accuracy of results is reached. A suitable solution for deciding upon the starting point of a steady-state analysis and two techniques for obtaining the final simulation results to a required level of accuracy are presented, together with pseudocode implementations.
From Washington: EC directives aim for market harmony
Authors: Crawford Diane 
Published: July 2002

The 1992 unification plans for the 12-nation European Community (EC) have surely been among the most dissected blueprints of the year. Politicians ponder trade agreements, economists refigure potential revenues, and media attention is unrelenting. Absorbing it all are those U.S. high tech industries hoping to make a lasting impression on what the economists, politicians and media all predict will be a $4 trillion market of over 300 million consumers.
Harmony has become the slogan adopted for the project. The EC Commission has spent the past five years identifying and implementing a program of close to 300 directives and regulations that would allow for the free movement of consumer products within the community. The goal of these directives, in addition to promoting European commerce and fair business competition, is to eliminate possible physical, technical or fiscal trade barriers. The result, they hope, is one harmonious marketplace.
Watching every note of this orchestration has been the U.S. Department of Commerce (DoC). Working with an internal program that includes the participation of senior officials from the International Trade Administration, the DoC has examined over 185 of the adopted or proposed directives issued by the EC Commission. Moreover, it consulted with trade associations and industry representatives to explore how these directives relate to current U.S. business practices and determine how they might affect future EC business dealings.
The DoC has published the results of its analyses in a three-volume series that examines directives for a rainbow of products and businesses. The recently released EC 1992: A Commerce Department Analysis of European Directives, Volume 3 features the Department's final roundup of EC Directives—primarily those stipulating technical requirements, nine of which pertain to computers and telecommunications.
Much attention has focused on how the high tech industries, particularly computers, software, telecommunications, and information technology, will be affected by EC standards, certification and testing issues. (See Communications, April 1990 and July 1990). According to Myles Denny-Brown, an international economist and coordinator for EC 92 activities for information technology industries at the DoC, the high tech industry regards EC market potential with cautious optimism. “I believe (industry) feels there is the possibility for some real liberalization there,” he says. “But there is also the possibility of some restrictiveness.”
Denny-Brown points out that standards and procurement issues are particularly important to build a competitive environment that would allow market growth to really take off the way it should. (see sidebar)
“Family Values” and Domestic Economies
Authors: Creed Gerald W. 
Published: July 2002

▪ Abstract  This review inverts the idiom “family values” to show the value of the family. It grounds this value in family economic activity but advocates an interactive approach in which cultural commitments to the family influence economic and political outcomes. Historical and ethnographic research on the family is mustered to illustrate the interaction and then combined with theories of capitalism and nationalism to account for the resonance of the family values discourse. A final section reviews the potential dangers of family-focused research.That tradesman who does not delight in his family will never long delight in his business. D. Defoe
Ischemic Preconditioning: From Adenosine Receptor to KATP Channel
Authors: Cohen Michael V. , Baines Christopher P. , Downey James M. 
Published: July 2002

▪ Abstract  Ischemic preconditioning is a phenomenon whereby exposure of the myocardium to a brief episode of ischemia and reperfusion markedly reduces tissue necrosis induced by a subsequent prolonged ischemia. It is hoped that elucidation of the mechanism for preconditioning will yield therapeutic strategies capable of reducing myocardial infarction. In the rabbit, the brief period of preconditioning ischemia and reperfusion releases adenosine, bradykinin, opioids, and oxygen radicals. The combined effect of the release of these substances on G proteins and the cell’s phospholipases induces the translocation and activation of the ε isozyme of protein kinase C. Protein kinase C appears to be the first element of a complex kinase cascade that is activated during the prolonged ischemia in preconditioned hearts. Current evidence indicates that this cascade contains at least one tyrosine kinase and ultimately leads to the activation of p38 mitogen-activated protein kinase. p38 Mitogen-activated protein kinase phosphorylates mitogen-activated protein kinase-activated protein kinase 2. Mitogen-activated protein kinase-activated protein kinase 2 phosphorylates HSP27, a 27-kDa heat shock protein that controls actin filament polymerization, and, therefore, affects the integrity of the cytoskeleton. Finally, mitochondrial adenosine 5′-triphosphate-sensitive K+ channels open, and the latter may be the final mediator of protection for ischemic preconditioning. The protective pathway has many builtin redundancies, perhaps creating a safety factor. These redundancies may also explain some of the species-related differences seen in ischemic preconditioning in which one redundant pathway may predominate over another.
Grasping after a Delay Shifts Size-Scaling from Absolute to Relative Metrics
Authors: Hu Y. , Goodale M. A. 
Published: July 2002

AbstractWe carried out three experiments designed to compare the effects of relative and absolute size on manual prehension and manual estimates of perceived size. In each experiment, right-handed subjects were presented with two different-sized 3-D objects in a virtual display and were instructed to pick up or estimate the size of one of them. In Experiment 1, subjects were requested to pick up the smaller one of two virtual objects under one condition and the larger one under the other condition. In fact, the target object was identical on all trials; it was simply paired with a smaller object on some trials and a larger object on others. To provide veridical haptic feedback, a real object was positioned beneath a mirror at the same location as the virtual target object. In Experiment 2, one of the virtual objects was marked with a red dot on its top surface. From trial to trial, the marked object was paired with a larger, smaller, or same-sized object. Subjects were instructed to always pick up the marked object on each trial. In both Experiment 1 and 2, half the subjects were tested in delayed grasping with a 5-sec delay between viewing the objects and initiating the grasp, and half in real-time grasping without a delay. Using the same display of virtual objects as in Experiment 2, subjects in Experiment 3 were requested to estimate the size of the marked object using their index finger and thumb (i.e., they showed us how big the object looked to them). After estimating the target object's size, they picked it up. All subjects gave their estimates either immediately or after a delay. Recording of hand movements revealed that when subjects in Experiments 1 and 2 picked up the target object in real time, their grip aperture in flight was not significantly affected whether the object was accompanied by a larger object or a smaller one. When subjects picked up the target object after a delay, however, their grip aperture in flight was larger when the target object was accompanied by a smaller object than when it was accompanied by a larger object. A similar size-contrast effect was also observed in Experiment 3 in which subjects gave manual estimates of the perceived size of the target object. This perceptual effect was observed both when the estimates were given immediately and when they were given after a 5-sec delay. These results suggest that normal (real-time) visuomotor control relies on absolute metrics, whereas delayed grasping utilizes the same relative metrics used by conscious perception.
Attention Mechanisms in Visual Search—An fMRI Study
Authors: Leonards Ute , Sunaert Stefan , Van Hecke Paul , Orban Guy A. 
Published: July 2002

Abstract
The human visual system is usually confronted with many different objects at a time, with only some of them reaching consciousness. Reaction-time studies have revealed two different strategies by which objects are selected for further processing: an automatic, efficient search process, and a conscious, so-called inefficient search [Treisman, A. (1991). Search, similarity, and integration of features between and within dimensions. Journal of Experimental Psychology: Human Perception and Performance, 17, 652-676; Treisman, A., & Gelade, G. (1980). A feature integration theory of attention. Cognitive Psychology, 12, 97-136; Wolfe, J. M. (1996). Visual search. In H. Pashler (Ed.), Attention. London: University College London Press]. Two different theories have been proposed to account for these search processes. Parallel theories presume that both types of search are treated by a single mechanism that is modulated by attentional and computational demands. Serial theories, in contrast, propose that parallel processing may underlie efficient search, but inefficient searching requires an additional serial mechanism, an attentional “spotlight” (Treisman, A., 1991) that successively shifts attention to different locations in the visual field. Using functional magnetic resonance imaging (fMRI), we show that the cerebral networks involved in efficient and inefficient search overlap almost completely. Only the superior frontal region, known to be involved in working memory [Courtney, S. M., Petit, L., Maisog, J. M., Ungerleider, L. G., & Haxby, J. V. (1998). An area specialized for spatial working memory in human frontal cortex. Science, 279, 1347-1351], and distinct from the frontal eye fields, that control spatial shifts of attention, was specifically involved in inefficient search. Activity modulations correlated with subjects' behavior best in the extrastriate cortical areas, where the amount of activity depended on the number of distracting elements in the display. Such a correlation was not observed in the parietal and frontal regions, usually assumed as being involved in spatial attention processing. These results can be interpreted in two ways: the most likely is that visual search does not require serial processing, otherwise we must assume the existence of a serial searchlight that operates in the extrastriate cortex but differs from the visuospatial shifts of attention involving the parietal and frontal regions.
Supramodal Effects of Covert Spatial Orienting Triggered by Visual or Tactile Events
Authors: Macaluso E. , Frith C. D. , Driver J. 
Published: July 2002

Abstract
Event-related functional magnetic resonance imaging was used to identify brain areas involved in spatial attention and determine whether these operate unimodally or supramodally for vision and touch. On a trial-by-trial basis, a symbolic auditory cue indicated the most likely side for the subsequent target, thus directing covert attention to one side. A subsequent target appeared in vision or touch on the cued or uncued side. Invalidly cued trials (as compared with valid trials) activated the temporo-parietal junction and regions of inferior frontal cortex, regardless of target modality. These brain areas have been associated with multimodal spatial coding in physiological studies of the monkey brain and were linked to a change in the location that must be attended to in the present study. The intraparietal sulcus and superior frontal cortex were also activated in our task, again, regardless of target modality, but did not show any specificity for invalidly cued trials. These results identify a supramodal network for spatial attention and reveal differential activity for inferior circuits involving the temporo-parietal junction and inferior frontal cortex (specific to invalid trials) versus more superior intraparietal-frontal circuits (common to valid and invalid trials).
Dissociation of Habit-Learning in Parkinson's and Cerebellar Disease
Authors: Witt K. , Nuhsman A. , Deuschl G. 
Published: July 2002

AbstractDamage to the medial-temporal region is known to result in declarative (explicit) memory deficits but nondeclarative (implicit) memory is largely unaffected by such lesions. Earlier studies have shown that some forms of implicit learning depend on cerebellar circuits but remain preserved following affections of the basal ganglia circuits. It is unknown which forms of implicit learning persist in patients with cerebellar pathology but are affected after basal ganglia lesions. Therefore, we determined if a test sensitive for habit-learning (probabilistic classification task) resulted in normal values for patients with cerebellar disease but resulted in affected results in patients with Parkinson's disease (PD). To this end, 23 patients with PD, 16 patients with familial or idiopathic cerebellar degeneration (CD), and 20 controls were tested for habit-learning. There was no impairment of patients with CD for the early learning period but there was abnormal learning in the PD group. For a later learning period, the patients with the PD showed improved performance. We conclude that the probabilistic learning task is an implicit, nonmotor learning task which is sensitive for basal ganglia pathology but remains unaffected in the case of cerebellar pathology. Such a test may be of special interest for the detection and possible neurobehavioral treatment of cognitive and motor deficits.
The Neural Circuitry Involved in the Reading of German Words and Pseudowords: A PET Study
Authors: Hagoort Peter , Indefrey Peter , Brown Colin , Herzog Hans , Steinmetz Helmuth , Seitz Rüdiger J. 
Published: July 2002

Abstract
Silent reading and reading aloud of German words and pseudowords were used in a PET study using (15O) butanol to examine the neural correlates of reading and of the phonological conversion of legal letter strings, with or without meaning. The results of 11 healthy, right-handed volunteers in the age range of 25 to 30 years showed activation of the lingual gyri during silent reading in comparison with viewing a fixation cross. Comparisons between the reading of words and pseudo-words suggest the involvement of the middle temporal gyri in retrieving both the phonological and semantic code for words. The reading of pseudowords activates the left inferior frontal gyrus, including the ventral part of Broca's area, to a larger extent than the reading of words. This suggests that this area might be involved in the sublexical conversion of orthographic input strings into phonological output codes. (Pre)motor areas were found to be activated during both silent reading and reading aloud. On the basis of the obtained activation patterns, it is hypothesized that the articulation of high-frequency syllables requires the retrieval of their concomitant articulatory gestures from the SMA and that the articulation of low-frequency syllables recruits the left medial premotor cortex.
Virtual Environments and the Enhancement of Spatial Behavior: Towards a Comprehensive Research Agenda
Authors: Durlach Nat , Allen Gary , Darken Rudy , Garnett Rebecca Lee , Loomis Jack , Templeman Jim , Wiegand Thomas E. von 
Published: July 2002

There is currently much research activity involving virtual environments (VEs) and spatial behavior (spatial perception, cognition, and performance). After some initial remarks describing and categorizing the different types of research being conducted on VEs and spatial behavior, discussion in this Forum paper focuses on one specific type, namely, research concerned with the use of VE technology for training spatial behavior in the real world. We initially present an overview of issues and problems relevant to conducting research in this area, and then, in the latter portion of the paper, present an overview of the research that we believe needs to be done in this area. We have written this paper for the forum section of Presence because, despite its length, it is essentially an opinion piece. Our aim here is not to report the results of research in our own laboratory nor to review the literature, as other available papers already serve these goals. Rather, the primary purpose of this paper is to stimulate open discussion about needed future research. In general, we believe that such a discussion can serve the research establishment as much as reports of completed work.
Evolutionary Body Building: Adaptive Physical Designs for Robots
Authors: Funes Pablo , Pollack Jordan 
Published: July 2002

Creating artificial life forms through evolutionary robotics faces a “chicken and egg” problem: Learning to control a complex body is dominated by problems specific to its sensors and effectors, while building a body that is controllable assumes the pre-existence of a brain. The idea of coevolution of bodies and brains is becoming popular, but little work has been done in evolution of physical structure because of the lack of a general framework for doing it. Evolution of creatures in simulation has usually resulted in virtual entities that are not buildable, while embodied evolution in actual robotics is constrained by the slow pace of real time. The work we present takes a step in addressing the problem of body evolution by applying evolutionary techniques to the design of structures assembled out of elementary components that stick together. Evolution takes place in a simulator that computes forces and stresses and predicts stability of three-dimensional brick structures. The final printout of our program is a schematic assembly, which is then built physically. We demonstrate the functionality of this approach to robot body building with many evolved artifacts.
Cultured Killers: Creating and Representing Foxhounds
Authors: Marvin Garry 
Published: July 2002

AbstractThis article concerns the related ideas of "presentation" and "representation" with regard to animals and suggests that the prefix "re" indicates a directing agent with its own concerns about the nature and status of animal presence. It further suggests that the representation of animals is perhaps always an expression of human concerns, desires, and imaginings. As with other domesticated nonhuman animals, foxhounds are not present in the world to fulfill their own purposes but there to fulfill these human desires and imaginings and are celebrated as the realization of a complex engagement of humans with the world of animals. The foxhound is central to English foxhunting and is given cultural meaning because of this context.The article offers a close anthropological interpretation of the production of this animal - a complex, cultural creation based on a canine form.
PRIESTLY DYNAMIC HOLINESS AND DEUTERONOMIC STATIC HOLINESS
Authors: Regev Eyal 
Published: July 2002

AbstractThere are several diverences between the laws of cult and the pre-supposition regarding ritual and impurity in the Priestly Schools and the book of Deuteronomy. Both sources regard the relationship between the priest and the laity and the access to the sacred in diverent ways. The fundamental reason that lies at the base of these diverent cultic systems is distinct perceptions of holiness. The diverence is not in the concept of what is holy and what is profane, but rather in the understanding of what holiness really is. The Priestly Schools view holiness as dynamic, sensitive and dangerous, and maintain that the access to the sacred should be limited. In contrast, in Deuteronomy holiness is static, and the access to the sacred is far less restricted, since it is not dangerous or threatening. In other words, in Deuteronomy holiness is not an active entity but a status. These opposing world-views regarding the holy are actually related to general conceptions about the character of the relationship between humans and nature on the one hand, and between man and God on the other hand.
PROGRESS, PURPOSE AND CONTINGENCY: A RESPONSE TO THOMAS BERRY'S THE GREAT WORK: OUR WAY INTO THE FUTURE
Authors: Goodenough Ursula 
Published: July 2002

AbstractThere is much to applaud in Berry's book The Great Work. However this response questions the framework of purposive, hierarchical progress of the universe which is outlined in Berry's narrative. It suggests that an alternative view is to see cosmic change as non-progressive and contingent - and that this perspective encourages the affirmation of wonder at the universe.
COSMOLOGICAL ETHICS? THE GREAT WORK
Authors: Eaton Heather 
Published: July 2002

AbstractAre we indeed ethically destitute, as suggests Thomas Berry? We are in an era of a barrage of ethical discourses, and yet Berry claims that are unable to respond to the radically new problematique facing any human communities. This article explores the idea of the macro and micro dimensions of ethics, noting the conventional reference points as well as the change of reference points Berry suggests. The discussion dwells on these two dimensions, and the interplay between them. The article also suggests that the religious/spiritual experiences of awakening, and presently to the cosmos, could also be considered as a source for ethics.