McLennan Community College

Groupware systems are computer-based systems that support two or more users engaged in a common task, and that provide an interface to a shared environment. These systems frequently require fine-granularity sharing of data and fast response times. This paper distinguishes real-time groupware systems from other multi-user systems and discusses their concurrency control requirements. An algorithm for concurrency control in real-time groupware systems is then presented. The advantages of this algorithm are its simplicity of use and its responsiveness: users can operate directly on the data without obtaining locks. The algorithm must know some semantics of the operations. However the algorithm's overall structure is independent of the semantic information, allowing the algorithm to be adapted to many situations. An example application of the algorithm to group text editing is given, along with a sketch of its proof of correctness in this particular case. We note that the behavior desired in many of these systems is non-serializable.

Groupware systems are computer-based systems that support two or more users engaged in a common task, and that provide an interface to a shared environment. These systems frequently require fine-granularity sharing of data and fast response times. This paper distinguishes real-time groupware systems from other multi-user systems and discusses their concurrency control requirements. An algorithm for concurrency control in real-time groupware systems is then presented. The advantages of this algorithm are its simplicity of use and its responsiveness: users can operate directly on the data without obtaining locks. The algorithm must know some semantics of the operations. However the algorithm's overall structure is independent of the semantic information, allowing the algorithm to be adapted to many situations. An example application of the algorithm to group text editing is given, along with a sketch of its proof of correctness in this particular case. We note that the behavior desired in many of these systems is non-serializable.

Previous researchers have proposed generalizations of Horn clause logic to support negation and non-determinism as two separate extensions. In this paper, we show that the stable model semantics for logic programs provides a unified basis for the treatment of both concepts. First, we introduce the concepts of partial models, stable models, strongly founded models and deterministic models and other interesting classes of partial models and study their relationships. We show that the maximal deterministic model of a program is a subset of the intersection of all its stable models and that the well-founded model of a program is a subset of its maximal deterministic model. Then, we show that the use of stable models subsumes the use of the non-deterministic choice construct in LDL and provides an alternative definition of the semantics of this construct. Finally, we provide a constructive definition for stable models with the introduction of a procedure, called backtracking fixpoint, that non-deterministically constructs a total stable model, if such a model exists.

Abstract The use of X-ray in the study of the mechanism of crystal growth showed that if the vapour of a substance came in contact with a cold surface, it condensed to form a solid, the structure of which depended on the temperature of the condensing surface. The authors announced recently that ice formed by condensation at low temperatures and pressures also changed form with temperature. Details of the apparatus and the results follow in this paper. 2-Method and Preliminary Work Analysis was carried out by the Hull-Debye-scherrer method, using the Ka doublet of copper. With a camera of 5 cm radius, photographs were obtained in 4 to 6 hours, using a shearer tube operated at 30 KV (R. M. S.) and 10 mA. The Ks line was removed from the radiation by a filter of nickel foil.

A query under an object-oriented data model exhibits characteristics which one finds in a relational query and those which clearly separate it from a relational query. The differences in turn have interesting impacts on the complexity of and strategy for query evaluation in object-oriented databases. The authors develop a model of a query under an object-oriented data model, and analyze the fundamental differences in the semantics of queries in object-oriented databases and relational databases.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

This paper describes a project underway to investigate computer support for collaboration. In particular, we focus on experience with and extensions to NoteCards, a hypertext-based idea structuring system. The forms of collaboration discussed include draft-passing, simultaneous sharing and online presentations. The requirement that mutual intelligibility be maintained between collaborators leads to the need for support of annotative and procedural as well as substantive activities.

To better understand the multiple individual factors that contribute to college cheating, we undertook a multivariate analysis of a national sample of 2,503 college students. Our findings indicated that demographic characteristics (e.g., gender, socioeconomic status, and year in college), character qualities (e.g., lack of self-control, others-oriented life purpose), college experience (e.g., academic preparation, extracurricular activities involvement, and working), and student perceptions and attitudes (e.g., attitude toward academic cheating, perception of faculty’s actions against cheating and cheating environment) are all significantly associated with academic cheating.

We report on results of training backpropagation nets with samples of hand-printed digits scanned off of bank checks and hand-printed letters interactively entered into a computer through a stylus digitizer. Generalization results are reported as a function of training set size and network capacity. Given a large training set, and a net with sufficient capacity to achieve high performance on the training set, nets typically achieved error rates of 4-5% at a 0% reject rate and 1-2% at a 10% reject rate. The topology and capacity of the system, as measured by the number of connections in the net, have surprisingly little effect on generalization. For those developing hand-printed character recognition systems, these results suggest that a large and representative training sample may be the single, most important factor in achieving high recognition accuracy. Benefits of reducing the number of net connections, other than improving generalization, are discussed.

Interfacial shear stress, peeling stress, and die cracking stress due to thermal and elastic mismatch in layered electronic assemblies are one of the major causes of the mechanical failure of electronic packages. A simple but rather accurate method is developed to estimate these thermal stresses for packages with different layer lengths. For layered electronics with thin adhesives, analytical expressions are obtained for interfacial shear stress and peeling stress, and they agree well with the finite element analysis, especially when the moduli of adhesive layers are significantly lower than the moduli of the other layers. An analytic expression of die cracking stress is also obtained for multilayer electronic assemblies.

Neuroimaging, neuropsychological, and psychophysical evidence indicate that concept retrieval selectively engages specific sensory and motor brain systems involved in the acquisition of the retrieved concept. However, it remains unclear which supramodal cortical regions contribute to this process and what kind of information they represent. Here, we used representational similarity analysis of two large fMRI datasets with a searchlight approach to generate a detailed map of human brain regions where the semantic similarity structure across individual lexical concepts can be reliably detected. We hypothesized that heteromodal cortical areas typically associated with the default mode network encode multimodal experiential information about concepts, consistent with their proposed role as cortical integration hubs. In two studies involving different sets of concepts and different participants (both sexes), we found a distributed, bihemispheric network engaged in concept representation, composed of high-level association areas in the anterior, lateral, and ventral temporal lobe; inferior parietal lobule; posterior cingulate gyrus and precuneus; and medial, dorsal, ventrolateral, and orbital prefrontal cortex. In both studies, a multimodal model combining sensory, motor, affective, and other types of experiential information explained significant variance in the neural similarity structure observed in these regions that was not explained by unimodal experiential models or by distributional semantics (i.e., word2vec similarity). These results indicate that during concept retrieval, lexical concepts are represented across a vast expanse of high-level cortical regions, especially in the areas that make up the default mode network, and that these regions encode multimodal experiential information.

The need for control in logic programs is now being recognized. This is particularly evident when one focuses on allowing updates in logic programs. In this paper we propose a language DatalogA which is an extension of Datalog with updates to base relations. We define some procedural constructs to allow update programs to be written in an easy manner. The (W,p) scheme of Dynamic Logic fits nicely into the semantics of DatalogA programs in which W is taken to be the set of all possible states of the program and p is the accessibility relation between states. We give declarative semantics and equivalent constructed model semantics for DatalogA programs. We show that in the absence of updates our semantics reduce to the classical semantics of Datalog. Finally, we show some examples of non-stratified programs expressed in DatalogA.

Is there a difference between the social capital developed in faith-based and secular poverty-to-work programs? Comparative field research investigating five faith-based and secular poverty-to-work programs in southeastern America finds that values expressed by a secular non-profit organization and two faith-based programs correspond with more activities that develop social capital than the programs run by a for-profit organization and a reinvented government agency. In all the programs this social capital is both 'bridging,' by crossing barriers of race, gender, and class, and 'bonding' by tying participants and staff into at least a temporary supportive community. The programs see that this social capital is effective in supporting low-income persons through the transition to full-time employment. In addition, the faith-based programs seek to extend the social capital by developing long-term ties between clients and local religious congregations. This paper also specifies how social capital is developed in these programs.

This study assesses faculty and student perceptions regarding dual relationships in mentoring, friendships, monetary interactions, informal social interactions, and romantic‐sexual relationships. Results indicate faculty‐student and gender differences.

Abstract Presently there are four generational cohorts in the workplace. Born from 1977 to 1997, the youngest cohort group, Generation Y, has 81 million members, of whom over 29 million are already in the workplace. The importance of leader‐subordinate relationships in the workplace has been confirmed. In recognizing this, leaders must identify and adapt to the era‐shaped needs of employees, who cannot fully participate in organizational life if their most urgent needs are not being met. The goal of this study was to determine leadership preferences of a Gen Y cohort as a means to enhance workplace relationships in the 21st‐century organization. A sequential, mixed‐methods study was employed to explore leadership preferences of a Gen Y cohort. Initially, focus‐group interviews were used to generate leadership themes. Based on these themes, an instrument was designed, and Gen Y business students from three higher education institutions were surveyed. Confirmatory factor analysis (CFA) was used to test the themes. Five leadership themes emerged in the focus groups and were confirmed through CFA.

Among mammals, post-reproductive life spans are currently documented only in humans and a few species of toothed whales. Here we show that a post-reproductive life span exists among wild chimpanzees in the Ngogo community of Kibale National Park, Uganda. Post-reproductive representation was 0.195, indicating that a female who reached adulthood could expect to live about one-fifth of her adult life in a post-reproductive state, around half as long as human hunter-gatherers. Post-reproductive females exhibited hormonal signatures of menopause, including sharply increasing gonadotropins after age 50. We discuss whether post-reproductive life spans in wild chimpanzees occur only rarely, as a short-term response to favorable ecological conditions, or instead are an evolved species-typical trait as well as the implications of these alternatives for our understanding of the evolution of post-reproductive life spans.

The clinical description of scurvy is well recorded in the history of medicine. Yet, because scurvy is relatively uncommon in industrially developed countries, it is often underdiagnosed, and unnecessary tests are performed. The result of a prolonged deficiency of ascorbic acid, scurvy is classically manifested by perifollicular hemorrhages, corkscrew hairs, large ecchymoses and hemorrhagic gingivitis. Although the disease is considered uncommon in the United States, two populations at greatest risk--the institutionalized elderly and alcoholics--are increasing.

Processes for crisis mitigation must permit coordination flexibility and dynamic change to empower crisis mitigation coordinators and experts to deal with unexpected situations. However, such mitigation processes must also provide enough structure to prevent chaotic response and increase mitigation effectiveness. Such combination of structure and flexibility cannot be effectively supported by existing workflow or groupware technologies. In this paper, we introduce the Collaboration Management Infrastructure (CMI) and describe its capabilities for supporting crisis mitigation processes. CMI provides a comprehensive Collaboration Management Model (CMM) and a corresponding federated system. CMM supports process templates that provide the initial activities, control and data flow structure, and resources needed to start mitigating a variety of crisis situations. In the event of a crisis, the appropriate process template is selected and instantiated. Crisis mitigation is achieved by escalating the instantiated process template. Escalation involves selecting and adding new process templates, creating new activities, roles, and task forces as needed to deal with the current demands in the crisis, and delegating responsibilities to process participants and task forces. CMM provides advanced composable primitives that empower crisis mitigation coordinators and experts to escalate the process. We provide an overview of the implementation of a federated CMI system and discuss our initial experience with various applications in the area of crisis management.

Cordyceps sinensis (Cs) and Rhodiola rosea (Rr) are herbs used in traditional Chinese medicine to treat a multitude of ailments as well as to enhance performance. The purpose of this research was to examine the effects of a formula containing Cs and Rr (Cs-Rr) on circulatory dynamics, specifically muscle tissue oxygen saturation (Sto(2)), in male subjects during maximal exercise. This study followed a double blind, randomized, placebo-treatment, pre-post test design. Capsules were administered to 8 subjects who were randomly assigned to 1 of 2 groups. The treatment group received Cs-Rr, and the control group received a placebo. All subjects performed 2 exercise stress tests to volitional fatigue on a cycle load ergometer. There were no significant (p </= 0.05) differences in Sto(2) slope, Sto(2) threshold (Sto(2T)), Vo(2)max, ventilatory threshold (V(T)), or time to exhaustion (T(E)) between or within the treatment or control group. In conclusion, Cs-Rr did not significantly enhance Sto(2).

We are developing a hand-printed character recognition system using a multi-layered neural net trained through backpropagation. We report on results of training nets with samples of hand-printed digits scanned off of bank checks and hand-printed letters interactively entered into a computer through a stylus digitizer. Given a large training set, and a net with sufficient capacity to achieve high performance on the training set, nets typically achieved error rates of 4-5% at a 0% reject rate and 1-2% at a 10% reject rate. The topology and capacity of the system, as measured by the number of connections in the net, have surprisingly little effect on generalization. For those developing practical pattern recognition systems, these results suggest that a large and representative training sample may be the single, most important factor in achieving high recognition accuracy. From a scientific standpoint, these results raise doubts about the relevance to backpropagation of learning models that estimate the likelihood of high generalization from estimates of capacity. Reducing capacity does have other benefits however, especially when the reduction is accomplished by using local receptive fields with shared weights. In this latter case, we find the net evolves feature detectors resembling those in visual cortex and Linsker's orientation-selective nodes.

Article Project Nick: meetings augmentation and analysis Share on Authors: Michael Begeman MCC, Austin, Texas MCC, Austin, TexasView Profile , Peter Cook MCC, Austin, Texas MCC, Austin, TexasView Profile , Clarence Ellis MCC, Austin, Texas MCC, Austin, TexasView Profile , Mike Graf MCC, Austin, Texas MCC, Austin, TexasView Profile , Gail Rein MCC, Austin, Texas MCC, Austin, TexasView Profile , Tom Smith MCC, Austin, Texas MCC, Austin, TexasView Profile Authors Info & Claims CSCW '86: Proceedings of the 1986 ACM conference on Computer-supported cooperative workDecember 1986 Pages 1–6https://doi.org/10.1145/637069.637071Online:03 December 1986Publication History 28citation571DownloadsMetricsTotal Citations28Total Downloads571Last 12 Months8Last 6 weeks1 Get Citation AlertsNew Citation Alert added!This alert has been successfully added and will be sent to:You will be notified whenever a record that you have chosen has been cited.To manage your alert preferences, click on the button below.Manage my AlertsNew Citation Alert!Please log in to your account Save to BinderSave to BinderCreate a New BinderNameCancelCreateExport CitationPublisher SiteGet Access