Input and output for microprocessors

Several alternative strategies for input and output for microprocessors are described, with examples for 8080 machines and the S-100 bus. The strategies are compared in terms of cost, complexity, flexibility, and speed in typical psychology laboratory tasks. Flag testing, interrupt processing, and direct memory access are considered in both parallel and serial modes.     

Computer complexes

By Judirh Duerk. San Diego: Lura Media, 1989.     

Response requirements as constraints on output

Two experiments studied how added response requirements affected fixed-interval schedule performance. Experiment 1 involved tandem fixed-interval fixed-ratio schedules, and Experiment 2 studied conjunctive fixed-interval fixed-ratio schedules. In both, pigeons' output, defined as overall response rate or as responses during the interval, first increased and then decreased as the ratio was raised. With small ratio requirements, the frequency of reinforcement in time either did not change or decreased slightly. With progressively larger ratios, reinforcement frequency decreased consistently. Alternative explanations were discussed. The first, a reinforcement theory account, was that response strength is an increasing monotonic function of both the response requirement and reinforcement frequency, and the bitonic output function represents interacting effects. Increases in the response requirement accompanied by small changes in reinforcement frequency enhance output, but further increases result in large enough decrements in reinforcement frequency so that output is lowered. The second explanation does not view reinforcement as a basic process but, instead, derives from concepts of economics and conservation. Organisms allocate their behavior among alternatives so as to maximize value, where value is a function of the responses that can occur in a given situation under the set of restrictions imposed by particular schedules. One form of this theory explicitly predicts that output is a bitonic function of ratio requirements in simple ratio schedules. However, it was not clear that this model could explain the present effects involving joint ratio and interval schedule restrictions.     

Clustering in the output of behavior

Pigeons exposed to fixed-interval schedules of 3, 5, 15, 40, and 120 minutes all maintained considerable variability in daily response rates for as many as 104 sessions. However, variations did not occur at random. Instead, rate in a session appeared dependent on those occurring previously. The series displayed a wave-like form arising because a group of high rates was followed by a group of low rates and vice versa. These sequential relations produced a curve having irregular periodicity, sometimes superimposed on a declining or rising linear trend. Whether grouping of response rates stemmed from experimental or extra-experimental sources was not determined. If the phenomenon was either totally or partially produced by the schedule itself, it suggests that response rate is determined by a combination of positive and negative feedback. Control by factors extrinisic to the experiment itself implies that response rate may be influenced by some rhythmic physiological process.     

Input and output in distributive theory

Distributive theories evaluate distributions of goods based on candidate recipients’ characteristics, e.g. how well off candidates are, how deserving they are, and whether they fare below sufficiency. But such characteristics vary across possible worlds, so distributive theories may differ in terms of the world which for them settles candidates’ characteristics. This paper examines how distributive theories differ in terms of whether candidate recipients’ relevant characteristics are grounded in the possible world that would take place if the distributor does not intervene (call it the “input” world) or if they are grounded in each possible world that the distributor can bring about through different decisions (call each an “output” world). We illustrate the importance of this distinction in relation to one distributive theory, prioritarianism. As we show, both input and output versions of prioritarianism are plausible interpretations of the literature, and there are good reasons to take input prioritarianism seriously. Ultimately, however, we argue that input prioritarianism should be rejected.     

Lilliputian Computer Ethics

This essay considers some ethical issues of nanotechnology and quantum computing, particularly the issue of privacy, and questions related to artificial intelligence, implants, and virtual reality. It then examines the claim that research in this field should be halted.     

升级你的电脑

我们每天面对着危险和致命的病毒,如谎言、诱惑和偷窃、自杀、流言蜚语、情绪失控等其他的错误念头,这些会毁掉你的个性、婚姻、孩子、工作和整个生活。这就是为什么我们必须小心选择那些进入自己头脑的东西,并及时清理头脑中的垃圾。     

Computer Technology Review

No abstract available for this article.     

Interactive braille output for blind computer users

Blind readers were tested using two methods of reading text displayed by an Apple microcomputer. The first method employed an Optacon system, a device that displays tactile representations of single characters, and the second used an interactive single electronic braille cell that displayed grade 1 braille characters. The results demonstrated no difference in accuracy or reading speed between these two methods. Thus, the serial presentation of braille characters at a single position appears to be a viable method of information transfer between computers and braille readers.     

Cerebellar output: motor and cognitive channels

The input to the cerebellum has long been known to originate from widespread regions of the cerebral cortex including the frontal, parietal and temporal lobes. The output of the cerebellum, however, was thought to project mainly to the primary motor cortex. Recent anatomical observations have challenged this view. It is now apparent that cerebellar output goes to multiple cortical areas, including not only the primary motor cortex, but also areas of premotor and prefrontal cortex. In fact, there is growing evidence that each of the areas of cerebral cortex that project to the cerebellum is also the target of cerebellar output. The cerebellar output to individual cortical areas originates from distinct clusters of neurons in the deep nuclei which we have termed `output channels'. The individual output channels to the cortical areas we have examined display little or no overlap. Physiological recordings in awake trained primates indicate that neurons in different output channels appear to be involved in distinct aspects of behavior, and in both motor and cognitive functions. These observations indicate that the cerebellar influence on the cerebral cortex is more extensive than previously recognized.