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Showing papers by "Georgia Institute of Technology published in 2000"


Journal ArticleDOI
TL;DR: In this article, the physical origin of surface plasmon absorption in gold nanoparticles with emphasis on the Mie and also the Maxwell-Garnett theory is discussed. And the effects of particle size and shape on the resonance condition are reviewed.
Abstract: Driven by the search for new materials with interesting and unique properties and also by the fundamental question of how atomic and molecular physical behaviour develops with increasing size, the field of nanoparticle research has grown immensely in the last two decades. Partially for these reasons, colloidal solutions of metallic (especially silver and gold) nanoparticles have long fascinated scientists because of their very intense colours. The intense red colour of colloidal gold nanoparticles is due to their surface plasmon absorption. This article describes the physical origin of the surface plasmon absorption in gold nanoparticles with emphasis on the Mie and also the Maxwell-Garnett theory and reviews the effects of particle size and shape on the resonance condition. A better understanding of the relationship between the optical absorption spectrum (in particular, the plasmon resonance) and such particle properties as its dimensions or surrounding environment can prove fruitful for the use of the ...

2,007 citations


Journal ArticleDOI
TL;DR: In this paper, the authors introduce the fundamentals of TEM and its applications in structural determination of shape-controlled nanocrystals and their assemblies, and demonstrate in situ TEM for characterizing and measuring the thermodynamic, electric, and mechanical properties of individual nanostructures, from which the structure−property relationship can be registered with a specific nanoparticle/structure.
Abstract: The physical and chemical properties of nanophase materials rely on their crystal and surface structures. Transmission electron microscopy (TEM) is a powerful and unique technique for structure characterization. The most important application of TEM is the atomic-resolution real-space imaging of nanoparticles. This article introduces the fundamentals of TEM and its applications in structural determination of shape-controlled nanocrystals and their assemblies. By forming a nanometer size electron probe, TEM is unique in identifying and quantifying the chemical and electronic structure of individual nanocrystals. Electron energy-loss spectroscopy analysis of the solid-state effects and mapping the valence states are even more attractive. In situ TEM is demonstrated for characterizing and measuring the thermodynamic, electric, and mechanical properties of individual nanostructures, from which the structure−property relationship can be registered with a specific nanoparticle/structure.

1,980 citations



Journal ArticleDOI
TL;DR: The Contingent Effectiveness Model of Technology Transfer (CEMT) as discussed by the authors is a model of technology transfer that assumes that technology effectiveness can take a variety of forms, including political effectiveness, capacity-building, and economic effectiveness.

1,585 citations


Journal ArticleDOI
TL;DR: Everyday computing is proposed, a new area of applications research, focussed on scaling interaction with respect to time, just as pushing the availiability of computing away from the traditional desktop fundamentally changes the relationship between humans and computers.
Abstract: The proliferation of computing into the physical world promises more than the ubiquitous availability of computing infrastructure; it suggest new paradigms of interaction inspired by constant access to information and computational capabilities. For the past decade, application-driven research on abiquitous computing (ubicomp) has pushed three interaction themes:natural interfaces, context-aware applications,andautomated capture and access. To chart a course for future research in ubiquitous computing, we review the accomplishments of these efforts and point to remaining research challenges. Research in ubiquitious computing implicitly requires addressing some notion of scale, whether in the number and type of devices, the physical space of distributed computing, or the number of people using a system. We posit a new area of applications research, everyday computing, focussed on scaling interaction with respect to time. Just as pushing the availiability of computing away from the traditional desktop fundamentally changes the relationship between humans and computers, providing continuous interaction moves computing from a localized tool to a constant companion. Designing for continous interaction requires addressing interruption and reumption of intreaction, representing passages of time and providing associative storage models. Inherent in all of these interaction themes are difficult issues in the social implications of ubiquitous computing and the challenges of evaluating> ubiquitious computing research. Although cumulative experience points to lessons in privacy, security, visibility, and control, there are no simple guidelines for steering research efforts. Akin to any efforts involving new technologies, evaluation strategies form a spectrum from technology feasibility efforts to long-term use studies—but a user-centric perspective is always possible and necessary

1,541 citations


Book
01 Jan 2000
TL;DR: The article gives an overview of technologies to distribute the execution of simulation programs over multiple computer systems, with particular emphasis on synchronization (also called time management) algorithms as well as data distribution techniques.
Abstract: Originating from basic research conducted in the 1970's and 1980's, the parallel and distributed simulation field has matured over the last few decades. Today, operational systems have been fielded for applications such as military training, analysis of communication networks, and air traffic control systems, to mention a few. The article gives an overview of technologies to distribute the execution of simulation programs over multiple computer systems. Particular emphasis is placed on synchronization (also called time management) algorithms as well as data distribution techniques.

1,217 citations


Journal ArticleDOI
TL;DR: Findings were robust across income, organization position, education, and computer self-efficacy levels, thus fortifying the lasting influence of gender-based early evaluations of the new technology.

1,150 citations


Journal ArticleDOI
TL;DR: The original ferrozine method has been modified to sequentially determine the Fe(II)/Fe(III) speciation in small volumes of fresh and marine water samples, at the submicromolar level as discussed by the authors.

1,127 citations


Journal ArticleDOI
TL;DR: A novel framework, MADAM ID, for Mining Audit Data for Automated Models for Instrusion Detection, which uses data mining algorithms to compute activity patterns from system audit data and extracts predictive features from the patterns.
Abstract: Intrusion detection (ID) is an important component of infrastructure protection mechanisms. Intrusion detection systems (IDSs) need to be accurate, adaptive, and extensible. Given these requirements and the complexities of today's network environments, we need a more systematic and automated IDS development process rather that the pure knowledge encoding and engineering approaches. This article describes a novel framework, MADAM ID, for Mining Audit Data for Automated Models for Instrusion Detection. This framework uses data mining algorithms to compute activity patterns from system audit data and extracts predictive features from the patterns. It then applies machine learning algorithms to the audit records taht are processed according to the feature definitions to generate intrusion detection rules. Results from the 1998 DARPA Intrusion Detection Evaluation showed that our ID model was one of the best performing of all the participating systems. We also briefly discuss our experience in converting the detection models produced by off-line data mining programs to real-time modules of existing IDSs.

1,033 citations


Journal ArticleDOI
TL;DR: Although these theoretical ideas and analytical procedures are fairly new, they may be relevant to a variety of psychophysiological or neurobiological variables.

1,008 citations


Journal ArticleDOI
TL;DR: In this paper, the authors compared the performance of gyrokinetic and gyrofluid simulations of ion-temperature gradient (ITG)instability and turbulence in tokamak plasmas as well as some tokak plasma thermal transportmodels.
Abstract: The predictions of gyrokinetic and gyrofluid simulations of ion-temperature-gradient(ITG)instability and turbulence in tokamak plasmas as well as some tokamak plasma thermal transportmodels, which have been widely used for predicting the performance of the proposed International Thermonuclear Experimental Reactor (ITER) tokamak [Plasma Physics and Controlled Nuclear Fusion Research, 1996 (International Atomic Energy Agency, Vienna, 1997), Vol. 1, p. 3], are compared. These comparisons provide information on effects of differences in the physics content of the various models and on the fusion-relevant figures of merit of plasma performance predicted by the models. Many of the comparisons are undertaken for a simplified plasma model and geometry which is an idealization of the plasma conditions and geometry in a Doublet III-D [Plasma Physics and Controlled Nuclear Fusion Research, 1986 (International Atomic Energy Agency, Vienna, 1987), Vol. 1, p. 159] high confinement (H-mode) experiment. Most of the models show good agreements in their predictions and assumptions for the linear growth rates and frequencies. There are some differences associated with different equilibria. However, there are significant differences in the transport levels between the models. The causes of some of the differences are examined in some detail, with particular attention to numerical convergence in the turbulence simulations (with respect to simulation mesh size, system size and, for particle-based simulations, the particle number). The implications for predictions of fusion plasma performance are also discussed.

Journal ArticleDOI
TL;DR: In this article, the electron and hole interband recombination was applied to gold nanorods with an aspect ratio of 2.0-5.4 and they were found to fluoresce with a quantum yield over a million times that of the metal.

Journal ArticleDOI
TL;DR: In this paper, the authors examine the investment behavior of market participants within different international markets (i.e., US, Hong Kong, Japan, South Korea, and Taiwan) specifically with regard to their tendency to exhibit herd behavior.
Abstract: We examine the investment behavior of market participants within diAerent international markets (i.e., US, Hong Kong, Japan, South Korea, and Taiwan), specifically with regard to their tendency to exhibit herd behavior. We find no evidence of herding on the part of market participants in the US and Hong Kong and partial evidence of herding in Japan. However, for South Korea and Taiwan, the two emerging markets in our sample, we document significant evidence of herding. The results are robust across various size-based portfolios and over time. Furthermore, macroeconomic information rather than firm-specific information tends to have a more significant impact on investor behavior in markets which exhibit herding. In all five markets, the rate of increase in security return dispersion as a function of the aggregate market return is higher in up market, relative to down market days. This is consistent with the directional asymmetry documented by McQueen et al. (1996) (McQueen, G., Pinegar, M.A., Thorley, S., 1996.

Journal ArticleDOI
TL;DR: In this article, the shape transformations of gold nanorods were investigated by using visible absorption spectroscopy and transmission electron microscopy (TEM) in order to analyze the final shape and size distribution.
Abstract: Gold nanorods have been found to change their shape after excitation with intense pulsed laser irradiation. The final irradiation products strongly depend on the energy of the laser pulse as well as on its width. We performed a series of measurements in which the excitation power was varied over the range of the output power of an amplified femtosecond laser system producing pulses of 100 fs duration and a nanosecond optical parametric oscillator (OPO) laser system having a pulse width of 7 ns. The shape transformations of the gold nanorods are followed by two techniques: (1) visible absorption spectroscopy by monitoring the changes in the plasmon absorption bands characteristic for gold nanoparticles; (2) transmission electron microscopy (TEM) in order to analyze the final shape and size distribution. While at high laser fluences (∼1 J cm-2) the gold nanoparticles fragment, a melting of the nanorods into spherical nanoparticles (nanodots) is observed when the laser energy is lowered. Upon decreasing the...

Journal ArticleDOI
TL;DR: A probabilistic syntactic approach to the detection and recognition of temporally extended activities and interactions between multiple agents and how the system correctly interprets activities of multiple interacting objects is demonstrated.
Abstract: This paper describes a probabilistic syntactic approach to the detection and recognition of temporally extended activities and interactions between multiple agents. The fundamental idea is to divide the recognition problem into two levels. The lower level detections are performed using standard independent probabilistic event detectors to propose candidate detections of low-level features. The outputs of these detectors provide the input stream for a stochastic context-free grammar parsing mechanism. The grammar and parser provide longer range temporal constraints, disambiguate uncertain low-level detections, and allow the inclusion of a priori knowledge about the structure of temporal events in a given domain. We develop a real-time system and demonstrate the approach in several experiments on gesture recognition and in video surveillance. In the surveillance application, we show how the system correctly interprets activities of multiple interacting objects.

Proceedings ArticleDOI
01 Apr 2000
TL;DR: A system for identifying people based on their footstep force profiles and its accuracy against a large pool of footstep data is tested and it is shown that the effect of footwear is negligible on recognition accuracy.
Abstract: We have created a system for identifying people based on their footstep force profiles and have tested its accuracy against a large pool of footstep data. This floor system may be used to identify users transparently in their everyday living and working environments. We have created user footstep models based on footstep profile features and have been able to achieve a recognition rate of 93%. We have also shown that the effect of footwear is negligible on recognition accuracy.

Journal ArticleDOI
TL;DR: The authors assesses several major streams in this research over the last two decades, which in some ways refute widely held a priori assumptions about similarities and differences between public and private organizations.
Abstract: Research comparing public and private organizations and examining the publicness of organizations represents a substantial and growing body of empirical evidence, relevant to many international issues in political economy and organization theory such as the privatization of public services. This article assesses several major streams in this research over the last two decades, which in some ways refute widely held a priori assumptions about similarities and differences between public and private organizations but which in some ways support such assumptions. The review covers research on goal complexity and ambiguity, organizational structure, personnel and purchasing processes, and work-related attitudes and values. The research results converge in important ways, but they also present anomalies. For example, in spite of virtually universal agreement among scholars that public organizations have more goal complexity and ambiguity, public managers do not differ from business managers in response to survey questions about such matters. Public managers do not differ from business managers on perceptions about organizational formalization, in spite of a chorus of assertions that government agencies have more red tape and rules than private firms have. Public managers do, however, show very sharp differences in response to questions about constraints under personnel and purchasing rules. The article concludes with an assessment of the credibility of these streams of research through consideration of alternative plausible hypotheses. No enemy of empiricism, Immanuel Kant simply insisted on empiricism's knowing its place. God, freedom, and immortality, Kant asserted, cannot be denied. Each is an a priori category of the mind and, as such, must necessarily be presupposed. One of J-PART 10(2000):2:447-469 modernity's strongest candidates for the a priori, and presumed 447/Journal of Public Administration Research and Theory at U niersity of G ergia on Feruary 9, 2012 http://jpaordjournals.org/ D ow naded rom Comparing Public and Private Organizations exemption from the hurly-burly world of empirical knowledge, is the public organization. Persons on the street and scholars in the academy will lecture at length on the character of public bureaucracies, blithely free of any concern over the need to show evidence for their assertions. Less confident of our own omniscience about this topic, we feel the need to look at evidence. Our article assesses nearly two decades of empirical research comparing public and private organizations with the following questions in mind: (1) What progress has come from the past twenty-five years or so of empirical research on differences between public and private organizations? (2) Why is there so often discrepancy between empirical research and a priori knowledge about public organizations? (3) Why has empirical research been so feckless in the face of well-established, but unproved, assumptions about public organizations? (4) Should this transcendence of the a priori over the empirical matter to anyone other than academic researchers? In this article we cannot resolve all these questions, but we make a start by reviewing several points in this comparative research where findings have converged on a particular conclusion. A second part of the article considers how much confidence we should place in this convergence, in view of various rival explanations that would suggest that the results are wrong. Before going on, we need to clarify what we mean by a priori views about the public-private distinction in organizational and managerial research. Here, a priori refers to untested assertions and foregone conclusions about this distinction. As we will elaborate below, two decades ago the literature on this topic was dominated by observations that had received scant empirical testing and confirmation. While empirical research has accumulated, these a priori views show remarkable staying power even though research has contradicted many of them. A striking aspect of the a priori views, one that made it necessary to test them empirically, is that there were—and still are—two general a priori positions on this topic, and they conflict with each other (see Rainey 1997, chap. 3). Many scholars in economics and political science have taken the position that public bureaucracies differ from private business firms in important ways (e.g., Barton 1980; Dahl and Lindblom 1953; Dixit 1997; Downs 1967). Their observations about the differences have coincided with the negative views of public bureaucracy in the popular culture, that Goodsell (1994) describes, coupled with the perception of business firms as inherently superior in efficiency and effectiveness. Fascinatingly, the people who specialized in analysis of 'Answers: (i) quite a bit, actually; (2) the organizations and management-organizational sociologists and unreliability of conventional wisdom; (3) psychologists, and researchers on business management—usually passive conveying of research; (4) yes! took a diametrically opposing position. They treated such UW-PART, April 2000 at U niersity of G ergia on Feruary 9, 2012 http://jpaordjournals.org/ D ow naded rom Comparing Public and Private Organizations distinctions as public vs. private and for-profit vs. nonprofit as crude stereotypes, taken seriously only by persons poorly educated in the field of organization theory. Prominent scholars denounced these distinctions as harmful and misleading oversimplifications that needed to be exorcised from the literature on organizations and management and replaced with typologies of organizations developed through sound empirical research. Some of the most eminent scholars in management and organization theory took pains to denounce the public-private distinction, or at least to point out that public and private organizations are more similar than they are different. This tradition continues and is manifest, among other ways, in a recent pronunciation by no less a social scientist than Herbert Simon (1995, 283, n. 3). Simon said that public, private, and nonprofit organizations are essentially identical on the dimension that receives more attention than virtually any other in discussions of the unique aspects of public organizations—the capacities of leaders to reward employees. The assumption that leaders in government organizations have less capacity to reward employees than do leaders in business firms, and that government needs to become more like business in this regard, has driven civil service reforms at all levels of government in the United States and in otheT nations. Yet a Nobel Laureate denies that such differences exist. Thus we have a strong a priori position among many economists and political scientists that treats a distinction between public and private organizations as a truism, while many organization theorists have treated this same distinction with contempt. This divergence among different fields complicates but also enhances the analysis of a priori assertions and of convergence in the research. When we refer to convergence of findings at various points in this article, we often are referring to convergence of findings that support one or the other of these two sides. Part of the value of the stream of research that we review is that it shows that both sides of this divergence were right in some ways 'Generalizations like these always involve and m c o m p i e te in other ways. The findings indicate definite coninjustices and oversimplifications them, • ^ .i_ i_ u » *: i -J cselves. Exceptions abound. Among mmy vergence on the point that we have substantial evidence of unporexampies are a typology developed by tant differences between public and private organizations. Yet organization theorists Peter Biau and they also indicate convergence on evidence that some of the freRichard Scott (1962) that included cate^ ^ y asserted differences receive little or no empirical confirgories for business firms and for public . , , , . . . . . . . . .. . . agencies, along with additional categories. m&tion and that the pubhc-pnvate distinction may well mvolve and many other references to public oversimplifications and stereotypes in those cases. Happily, both organizations by organization dworists sides can take pride in being right in certain ways. (Perry and Rainey 1988). The Dahl and Lindblom analysis and the Downs anal, » : « . _ » »i_ • -i •»• ysis are actually much more balanced and W e n e e d however, to continue to sort out the similarities carefully reasoned than the phrasing here and differences, whether or not our results please one side of the might suggest. debate or the other. The analysis of this topic has important 449/J-PART, April 2000 at U niersity of G ergia on Feruary 9, 2012 http://jpaordjournals.org/ D ow naded rom Comparing PubUc and Private Organizations implications for major current theoretical and practical issues, including these: privatization of public services; allocation of functions and tasks among sectors; the nature of the sectors themselves; the dimensions that define the sectors, including their complex overlapping and blurring with the third and nonprofit sectors; administrative reforms and organizational change; and the theoretical and practical analysis of major administrative topics, such as organizational goals, structure, and individual motivation and work attitudes. EMPIRICAL RESULTS COMPARING PUBUC AND PRIVATE ORGANIZATIONS Research that compares public and private organizations and examines the publicness of organizations now represents a substantial body of empirical evidence. Twenty-five years ago, a systematic empirical research base had just begun to accumulate. In one comprehensive review of writings about public and private organizations (Rainey, Backoff, and Levine 1976), less than ten of the nearly one hundred papers and books cited provided propositions based on empirical research. By contrast,

Journal ArticleDOI
TL;DR: A mechanism for long-range charge transport in DNA that depends on its spontaneous structural distortion, which is called phonon-assisted polaron hopping is described, which provides a framework for understanding the reactions and charge-transport properties of DNA.
Abstract: Damage to DNA is often caused by oxidative reactions. In one such process, an electron is lost from a base, forming its radical cation. Further reaction of the radical cation can lead to permanent change, which results in mutation. This Account is a report on oxidative damage to DNA caused by irradiation of anthraquinone derivatives, which are either randomly bound to the DNA or attached to it covalently at specific locations. Radical cations introduced in the DNA by the excited quinone cause damage both near to it and far away. We describe a mechanism for long-range charge transport in DNA that depends on its spontaneous structural distortion, which we call phonon-assisted polaron hopping. This mechanism, and its extension, provides a framework for understanding the reactions and charge-transport properties of DNA.

Journal ArticleDOI
TL;DR: In a survey of 2,200 individuals, the authors examined the degree to which work environments are structured to complement the creative requirements of jobs and found that proximal job characteristics were more strongly associated with a combined objective and perceptual measure of job-required creativity than were distal organizational characteristics.
Abstract: In a survey of 2,200 individuals, the authors examined the degree to which work environments are structured to complement the creative requirements of jobs. Regression analyses indicated that proximal job characteristics were more strongly associated with a combined objective and perceptual measure of job-required creativity than were distal organizational characteristics. Furthermore, higher job satisfaction and lower intentions to leave were found for individuals whose work environments complemented the creative requirements of their jobs.

Journal ArticleDOI
TL;DR: A series of giant metal-cluster compounds, each composed of a gold core and a glutathione (GSH) adsorbate layer, have been prepared from Au(I)SG polymers and separated by gel electrophoresis, using methods reported in a recent Letter as discussed by the authors.
Abstract: A series of giant metal-cluster compounds, each composed of a gold core and a glutathione (GSH) adsorbate layer, have been prepared from Au(I)SG polymers and separated by gel electrophoresis, using methods reported in a recent Letter [J. Phys. Chem. B 1998, 102, 10643−6]. Identification of the separated compounds by core mass is accomplished through laser desorption mass spectrometry of matrix-diluted films. Three principal compounds have core masses of ca. 4.3, 5.6, and 8.2 kDa (in the range of ∼20−40 Au atoms), and show structured optical absorption spectra with clear optical absorption onsets near 1.7, 1.3, and 1.0 eV, respectively. Each of these shows unusually strong chiroptical activity in the metal-based electronic transitions across the near-infrared, visible, and near-ultraviolet regions, whereas neither the crude (unseparated) mixture nor its higher molecular weight components possess such strong optical activity. The location and strength of the optical activity suggest a metal electronic struc...

Journal ArticleDOI
TL;DR: Although typically excluded from strategic human resource models, bundles of work-family policies may be an HR approach related to competitive advantage as discussed by the authors, and Symbolic action and resource-based views pr...
Abstract: Although typically excluded from strategic human resource models, bundles of work-family policies may be an HR approach related to competitive advantage. Symbolic action and resource-based views pr...

Proceedings ArticleDOI
01 Jul 2000
TL;DR: This paper presents techniques for analyzing a video clip to extract its structure, and for synthesizing a new, similar looking video of arbitrary length, and combines video textures with view morphing techniques to obtain 3D video textures.
Abstract: This paper introduces a new type of medium, called a video texture, which has qualities somewhere between those of a photograph and a video. A video texture provides a continuous infinitely varying stream of images. While the individual frames of a video texture may be repeated from time to time, the video sequence as a whole is never repeated exactly. Video textures can be used in place of digital photos to infuse a static image with dynamic qualities and explicit actions. We present techniques for analyzing a video clip to extract its structure, and for synthesizing a new, similar looking video of arbitrary length. We combine video textures with view morphing techniques to obtain 3D video textures. We also introduce video-based animation, in which the synthesis of video textures can be guided by a user through high-level interactive controls. Applications of video textures and their extensions include the display of dynamic scenes on web pages, the creation of dynamic backdrops for special effects and games, and the interactive control of video-based animation.

Journal ArticleDOI
TL;DR: This article contains brief descriptive discussions of the key physical features of all new algorithms and theoretical models, together with sample calculations that illustrate their performance.
Abstract: Q-Chem 2.0 is a new release of an electronic structure programpackage, capable of performing first principles calculations on the ground andexcited states of molecules using both density functional theory and wavefunction-based methods. A review of the technical features contained withinQ-Chem 2.0 is presented. This article contains brief descriptive discussions of thekey physical features of all new algorithms and theoretical models, together withsample calculations that illustrate their performance. c 2000 John Wiley S electronic structure; density functional theory;computer program; computational chemistry Introduction A reader glancing casually at this article mightsuspect on the basis of its title that it is a thinlydisguised piece of marketing for a program pack-age. This is not the case. Rather, it is an attemptto document the key methodologies and algorithmsof our electronic structure program package, Q-Chem 2.0, in a complete and scientifically accurateway, with full references to the original literature.This is important for two principal reasons. First,while the use of electronic structure programs isburgeoning, many users of such programs do nothave much feel for the underlying algorithms thatmake large-scale calculations routine even on suchreadily available hardware as personal computers.Therefore, a link between the program package andthe original literature that is written at the level ofan introductory overview can be a useful bridge.Second, while citations of large-scale commercialprograms in published applications are tradition-ally part of the conditions of use of such codes, they

Journal ArticleDOI
TL;DR: This definition is based on a particular set of eigenvectors of the DFT matrix, which constitutes the discrete counterpart of the set of Hermite-Gaussian functions, and is exactly unitary, index additive, and reduces to the D FT for unit order.
Abstract: We propose and consolidate a definition of the discrete fractional Fourier transform that generalizes the discrete Fourier transform (DFT) in the same sense that the continuous fractional Fourier transform generalizes the continuous ordinary Fourier transform. This definition is based on a particular set of eigenvectors of the DFT matrix, which constitutes the discrete counterpart of the set of Hermite-Gaussian functions. The definition is exactly unitary, index additive, and reduces to the DFT for unit order. The fact that this definition satisfies all the desirable properties expected of the discrete fractional Fourier transform supports our confidence that it will be accepted as the definitive definition of this transform.

Posted Content
TL;DR: This paper found that work group perceptions of cohesion and supervisor visibility in demonstrating procedural justice were associated with the development of procedural justice climate, which was positively associated with helping behaviors after the effects of individual procedural justice perceptions were controlled for.
Abstract: Current conceptualizations of procedural justice focus largely on the individual level of analysis; no framework exists for examining procedural justice's social context. Empirical tests reported here offer some support for group-level and cross-level hypotheses. Work group perceptions of cohesion and supervisor visibility in demonstrating procedural justice were associated with the development of procedural justice climate. Procedural justice climate was positively associated with helping behaviors after the effects of individual procedural justice perceptions were controlled for.

Journal ArticleDOI
01 Jun 2000
TL;DR: An invasive alternative to externally applied brain-computer interface devices requires implantation of a special electrode into the outer layers of the human neocortex to control the cursor for the production of synthetic speech and typing.
Abstract: Describes an invasive alternative to externally applied brain-computer interface (BCI) devices. This system requires implantation of a special electrode into the outer layers of the human neocortex. The recorded signals are transmitted to a nearby receiver and processed to drive a cursor on a computer monitor in front of the patient. The authors' present patient has learned to control the cursor for the production of synthetic speech and typing.

Journal ArticleDOI
TL;DR: It is concluded that dynamic mechanical conditioning during tissue culture leads to an improvement in the properties of tissue-engineered blood vessel constructs in terms of mechanical strength and histological organization.
Abstract: Dynamic mechanical conditioning is investigated as a means of improving the mechanical properties of tissue-engineered blood vessel constructs composed of living cells embedded in a collagen-gel scaffold. This approach attempts to elicit a unique response from the embedded cells so as to reorganize their surrounding matrix, thus improving the overall mechanical stability of the constructs. Mechanical conditioning, in the form of cyclic strain, was applied to the tubular constructs at a frequency of 1 Hz for 4 and 8 days. The response to conditioning thus evinced involved increased contraction and mechanical strength, as compared to statically cultured controls. Significant increases in ultimate stress and material modulus were seen over an 8 day culture period. Accompanying morphological changes showed increased circumferential orientation in response to the cyclic stimulus. We conclude that dynamic mechanical conditioning during tissue culture leads to an improvement in the properties of tissue-engineered blood vessel constructs in terms of mechanical strength and histological organization. This concept, in conjunction with a proper biochemical environment, could present a better model for engineering vascular constructs. © 2000 Biomedical Engineering Society. PAC00: 8719Rr, 8714Ee, 8718-h, 8768+z

Journal ArticleDOI
TL;DR: A framework for examining procedural justice's social context has been proposed by as mentioned in this paper, but no framework exists for examining the social context of procedural justice, and no framework has been defined.
Abstract: Current conceptualizations of procedural justice focus largely on the individual level of analysis; no framework exists for examining procedural justice's social context. Empirical tests reported h...

Proceedings ArticleDOI
29 Feb 2000
TL;DR: The paper describes the methodology and the software development of XWRAP, an XML-enabled wrapper construction system for semi-automatic generation of wrapper programs, and introduces and develops a two-phase code generation framework.
Abstract: The paper describes the methodology and the software development of XWRAP, an XML-enabled wrapper construction system for semi-automatic generation of wrapper programs. By XML-enabled we mean that the metadata about information content that are implicit in the original Web pages will be extracted and encoded explicitly as XML tags in the wrapped documents. In addition, the query based content filtering process is performed against the XML documents. The XWRAP wrapper generation framework has three distinct features. First, it explicitly separates tasks of building wrappers that are specific to a Web source from the tasks that are repetitive for any source, and uses a component library to provide basic building blocks for wrapper programs. Second, it provides a user friendly interface program to allow wrapper developers to generate their wrapper code with a few mouse clicks. Third and most importantly, we introduce and develop a two-phase code generation framework. The first phase utilizes an interactive interface facility to encode the source-specific metadata knowledge identified by individual wrapper developers as declarative information extraction rules. The second phase combines the information extraction rules generated at the first phase with the XWRAP component library to construct an executable wrapper program for the given Web source. We report the initial experiments on performance of the XWRAP code generation system and the wrapper programs generated by XWRAP.

Journal ArticleDOI
TL;DR: In this article, the current Eulerian models are found to represent well the primary processes impacting the evolution of trace species in most cases, though some exceptions may exist, such as concentrated power plant plumes, which are treated only approximately.