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The accurate detection of UV radiation is required in a wide range of chemical industries and environmental or biological related applications. Conventional methods taking advantage of semiconductor photodetectors suffer from several drawbacks such as sophisticated synthesis and manufacturing procedure, not being able to measure the accumulated UV dosage as well as high defect density in the material. Searching for new strategies or materials serving as precise UV dosage sensor with extremely low detection limit is still highly desirable. In this work, a radiation resistant uranium coordination polymer [UO2(L)(DMF)] (L = 5-nitroisophthalic acid, DMF = N,N-dimethylformamide, denoted as compound 1) was successfully synthesized through mild solvothermal method and investigated as a unique UV probe with the detection limit of 2.4 × 10-7 J. On the basis of the UV dosage dependent luminescence spectra, EPR analysis, single crystal structure investigation, and the DFT calculation, the UV-induced radical quenching mechanism was confirmed. Importantly, the generated radicals are of significant stability which offers the opportunity for measuring the accumulated UV radiation dosage. Furthermore, the powder material of compound 1 was further upgraded into membrane material without loss in luminescence intensity to investigate the real application potentials. To the best of our knowledge, compound 1 represents the most sensitive coordination polymer based UV dosage probe reported to date.

During the current period of rapid technological change, business students need to emerge from their introductory course in Information Systems (IS) with a set of fundamental principles to help them “think about Information Technology (IT)” in future courses and the workplace. Given the digital revolution, they also need to appreciate the role of information in business as well has how to meet the challenges involved in managing information effectively. This paper addresses both those needs by presenting a fundamental principle concerning information management: How you store information affects how you can retrieve it. The paper commences by presenting the principle in a manner that can be used to introduce it to the class. It continues by providing numerous concepts and examples that draw on the principle and that students are likely to encounter in the core IS course, subsequent courses, and their real-world use of technology. The paper concludes by raising a set of issues suitable for class discussion or exam questions.

Browser-based applications (BBAs), applications built on top of web browsers, dominate the world of Internet Applications today but are fundamentally flawed because the web browser is a weak platform for applications. Three characteristics of the browser—page orientation, statelessness, and limited computation—combine to produce a set of practical problems for BBA users. These problems include delays and discontinuities, confusion and errors, clumsy interfacing and limited functionality, printing problems, and filing difficulties. The paper analyzes these usability problems, providing numerous examples and tracing them back to underlying browser characteristics. The paper also examines the factors that make BBAs so popular despite their flaws. The paper concludes by considering directions for understanding the phenomenon better and for improving the current state of Internet Applications.

This is the second in a series of papers concerning forensic immigration social work. The first paper examined the broad issues and types of cases that require consultation by a forensic social worker in immigration cases. This paper will examine the pertinent legal standards that the forensic social worker must be aware of and the essential areas of inquiry in the evaluation of spousal abuse cases. The following two papers will examine the other two major types of cases referred from immigration lawyers: asylum and criminal and “hardship” immigration cases. The final paper in the series will examine the forensic social worker's presentation of the case as expert testimony in immigration court and highlight winning strategies.

Incident reporting has emerged as a cornerstone of sound quality improvement programs. Sentinel events, "a serious and undesirable occurrence involving the loss of life, limb, or function of an individual served" (Joint Commission on Accreditation of Healthcare Organizations, 1996), is a mandated indicator for Joint Commission standards of accreditation for audited healthcare facilities. Properly investigated and documented individual incidents can lead to systemic improvements, which may enhance the quality of client care and the integrity of the healthcare facility. This article proposes a systemic approach to the incident review (IR) process in long-term healthcare facilities. This comprehensive approach incorporates identification, investigation, and management of the IR process from the inception of a problem to the continued follow-up to ensure that improvement plans are effectively implemented.

Building models of expert decision-making behavior from examples of experts’ decisions continues to receive considerable research attention. In the 1960's and 70's, linear models derived by statistical methods were studied extensively. More recently, rule-based expert systems derived by induction algorithms have been the focus of attention. Few studies compare the two approaches. This paper reports on a study that compared linear models derived by logistic regression with rule-based systems produced by two induction algorithms—ID3 and the genetic algorithm. The techniques performed comparably in modeling the experts at one task, graduate admissions, but differed significantly at a second task, bidder selection.

Future space based telescopes will need apertures and focal lengths that exceed the dimensions of the launch vehicle shroud. In addition to deploying the primary mirror and secondary mirror support structure, these large telescopes must also deploy the stray light and thermal barriers needed to ensure proper telescope performance. The authors present a deployable light and thermal optical barrel assembly approach for a very large telescope with a variable sun angle and fast slew rate. The Strain Energy Deployable Optical Barrel Assembly (SEDOBA) uses elastic composite hinges to power the deployment of a hierarchical truss structure that supports the thermal and stray light shroud material that form the overall system. The paper describes the overall design approach, the key component technologies, and the design and preliminary testing of a self deploying scale model prototype.

The Decision Support Systems (DSS) literature is in general agreement that use of DSS leads to individual and organizational change, but there is no consensus as to whether DSS and their designers serve as agents for directed or nondirected change. Researchers have proceeded from two different sets of premises, drawing different conclusions about the nature of DSS. This paper considers both views, examining how differences in designers' attitudes toward change agency ought to be manifest in the features of the DSS they implement. Two attributes of DSS, “system restrictiveness” and “decisional guidance,” are discussed as the basis for understanding differences in DSS following from differences in designer attitudes toward change. Using these two attributes, four DSS strategies for directed change and five strategies for nondirected change are presented.

This paper reports observations and analysis of picometer scale spontaneous vibrations in a precision deployable boom under thermal loading. The structural test article is a deployable boom previously flown in space. It exhibited spontaneous vibrations during the temperature rise following a night to day transition on orbit. In an attempt to reproduce the spontaneous vibrations on the ground, the test article was thermally loaded within a mechanically stabilized test environment. Spontaneous vibrations were induced in these ground experiments. The vibrations were at a scale of motion for which current theories would not expect such a release. The amplitudes of these vibrations were on the order of a few dozen picometers, and the frequency was near 1500 Hz. Evidence of wave dispersion was detected in the vibrations.

This paper presents an analytical, computational and experimental study of the deployment dynamics of an elastically deployable solar array. The thin film array is folded in multiple stages with elastic hinge and deployed depth stiffening elements and then allowed to deploy under its own elastic strain energy. A computational model of the geometrically nonlinear deployment is assembled using reduced order models of the elastic hinge elements. Restoring torque models developed for each hinge line are validated through isolated testing of each of three deployment stages. Both linear and nonlinear models of the corresponding elastic mechanisms are updated from the results of these experiments. The ground tests use a simple low-stiffness suspension system and videometry to measure the angular displacement of the deploying panel to be measured. The angular velocity and acceleration are computed from this data for use in the model updating process. The testing is performed on an early version of the array, called the engineering model (EM), and on the flight unit. For the first stage, the root hinge, the classical and computational models adequately predicted experimental results. The second stage, or z-fold deployment, experimental results indicated a stiffness that was 2.3 times smaller than the predicted stiffness for the EM. Flight unit results more closely matched predictions. For the final stage of deployment, the tri-fold, the nonlinear elastic response of the shallow shell, or "tape" hinges, is predicted by analytical models of their post-buckled mechanics. For this stage, the observed long range stiffness is greater than the expected results based on thin plate theory and computational simulation. Further testing of flight unit components and updating model parameters will improve the understanding of the deployment dynamics of the array.

Elastic, lenticular hinges have been used for many years to provide simple, reliable, repeatable deployment of spacecraft structural components. Recent advances in high performance elastically flexible composites have opened up the application field for this useful deployment component by providing lighter, more thermally stable hinges as well as designs that can meet a much wider range of requirements. This paper describes recent advances in composite hinge performance through a combination of analysis and testing.

This paper presents an analysis of the buckling of tape springs due to axial compressive loads and end moments. The motivation for this work is to derive design guidelines for axial loading of hinges made from tape springs. A previously derived non-dimensionalized, nonlinear analytical model of the buckling problem including load eccentricity and geometric imperfections is presented. The finite difference method is used to solve this analytical model. An experimental apparatus has been built to verify the results of the analytical model. Preliminary results from the finite difference model and experiments are presented.

This paper presents an investigation of the bending-induced buckling response of doubly slit cylindrical shells. The goal of this work is to determine a design-relevant parametric model of the load-displacement response during stowing and deployment of folding hinges built from opposing doubly slit cylindrical shells. This relationship will assist in the design and modeling of structures built from these folding hinges for use in elastically deployed structures. Results of an investigation into computational analysis procedures for modeling the snap-back problem are presented. A review of the literature indicates that previous work has not dealt with the snap-back phenomenon that needs to be considered for the folding hinge application. The few analytical models that can be used to verify these finite element model predictions are presented, and comparisons are made to the current finite element results. A test apparatus is described which imposes controlled displacement and/or rotation at the end of the doubly slit cylindrical shells up to and through snap-back, while end moment and planar forces are measured.

Applications that run on top of web browsers dominate the Internet today. Given the many similarities among these applications' features, positive transference from one to another is often seen as an important source of ease-of-use for such applications. This paper examines the many differences in the way similar features are implemented in different browser-based applications, analyzing the way these inconsistencies can lead to negative transference (interference) that degrades rather than enhances usability.

The transfer of residential clients with mental retardation to inpatient psychiatric care units (IPUs) presents several areas in which clinical and administrative incidents can occur. Incident review management can be applied as an effective administrative tool to improve the transfer of such clients by considering the needs of clients in the context of their caregivers and the goals of the IPU. This article introduces eight criteria to facilitate and evaluate the transfer of such clients and help reduce the rate of incidents.

Incident review (IR) is a process for achieving a better understanding of problems related to the health and safety of clients and the integrity of healthcare facilities. The purpose of IR is to identify and document adverse incidents through fact-finding. Incidents may vary in both type and levels of seriousness. Through careful documentation, investigation, and committee review, patterns of healthcare delivery can be discerned. The goal of IR is the development of systemic performance improvements in healthcare delivery, which may serve to anticipate and deter the recurrence of similar incidents. IR ensures that the quality and performance of healthcare delivery in the facility continue to be improved by both administrative and clinical staff members. This article examines IR in the context of the inpatient psychiatry unit.

INTRODUCTION This paper reports observations and analysis of picometer scale spontaneous vibrations in a precision deployable boom under thermal loading. The structural test article is a deployable boom previously flown in space that exhibited spontaneous vibrations during the temperature rise following a night to day transition on orbit. In an attempt to reproduce the orbital behavior on the ground, the test article was thermally loaded within a stabilized test environment. Spontaneous vibrations were also induced in these experiments. The amplitudes of these vibrations were on the order of a few dozen picometers, and the frequency was near 1500 Hz. Evidence of wave dispersion was detected in the vibrations. An analysis is presented that interprets the vibrations as the sudden release of stored strain energy in an unknown component of the truss. It is shown that the level of kinetic energy in the vibrations is comparable with the strain energy that would be released from a truss member undergoing comparable amplitude of deformation. This supports the notion that friction in a mechanism or a material instability led to the spontaneous vibrations, but if so, they were in a range of motion for which current theories would not expect such a release. * Graduate Research Assistant, Student Member AIAA Mark.Silver@Colorado.edu (303) 492-3576 t Associate Professor, Associate Fellow AIAA Lee.Peterson@Colorado.edu (303)492-1743 £ Research Associate, Member AIAA Lisa.Hardaway@Colorado.edu (303) 589-4565 Copyright © 2001 by Mark Silver, Lee Peterson, and Lisa Hardaway. Published by the American Institute of Aeronautics and Astronautics, Inc. with permission. Structures are designed to hold a specific shape under specified load conditions. For space-based telescopes, the structural stability must be maintained to within a small fraction of a wavelength of light. Current requirements for the Next Generation Space Telescope (NGST) may require dynamic stability of the reflector panel shape to within a few nanometers. Interferometric telescopes, such as the Space Interferometry Mission (SIM), require this level of stability or better, but over a bandwidth of perhaps 1000 Hz. These requirements are necessary if the structural imperfection is to be kept compatible with the active optical elements of the telescope. Little is available in the literature about mechanics and stability at this scale of motion. Micrometer level instabilities in materials and structures have been recognized for over 100 years, yet testing at the nanometer level has been a relatively recent development. High bandwidth instruments now exist that can measure nanometer level displacements and micro gravity level accelerations. The use of these instruments has resulted in a small but growing number of experiments on the behavior of structures at these scales. The present study provides additional evidence in this regard. The objective is to measure and characterize the stability of a deployed boom under thermal loading. It is well known at the macroscopic and microscopic scales of motion that thermoelastic loading of a spacecraft structure can induce spontaneous vibrations. In the first set of HST solar arrays, for example, thermally induced bending caused a well-known pointing jitter. Analysis of the jitter problem showed that thermally induced bending in the Bi-STEM structural supports for the solar arrays caused the oscillations. The bending was, in turn, caused by temperature changes when HST passed from shadow to sunlight. The vibrations resulted when the induced loads exceeded the Coulombic friction threshold, American Institute of Aeronautics and Astronautics (c)2001 American Institute of Aeronautics & Astronautics or Published with Permission of Author(s) and/or Author(s)' Sponsoring Organization. causing a sudden loss of stiffness and a resulting release of strain energy. Such phenomena are well recognized among the spacecraft structural dynamics community. Perhaps what may be little appreciated is that the trigger of such frictional instabilities is associated in the theoretical literature with pre-slip deformations on the order of microns, and with critical velocities on the order of microns per second or more. Unless the load and load rate causes the frictional interface to approach both these critical thresholds, there should not be an induced vibration. In that case, a jointed structure should retain its stability, undergoing at most progressive microslip shearing in the friction interfaces. Said another way, if gross slip is not induced in the friction interfaces in such a way to create an unstable stiffness, there should be no sudden release of strain energy. One could simply design structures to avoid this limit. However, this expectation is based on models derived entirely from empirical evidence gathered at the macroscopic and microscopic deformation scale. Space telescopes need to be stable at the nanometer scale (perhaps below). With no theory to provide a basis, then, the first steps must be experimental. To provide evidence in this regard, the NASA Jet Propulsion Laboratory (JPL) performed flight tests on a deployed boom in the Interferometry Program Experiment (IPEX-2). The objective of IPEX-2 was to detect and characterize any spontaneous vibrations that might be induced by thermal loads in a space environment. The results of the flight test were presented in Reference 7. Perhaps the most puzzling data was collected immediately following a particular night to day transition. As the truss was heated, the temperature rose approximately 30 degrees C. Many spontaneous vibrations were recorded at this time. Following the flight, exploratory testing at JPL indicated that these low amplitude thermal snaps might have been observed on the ground during one of the post-flight experiments. A subsequent thermoelastic analysis at JPL indicated that the loads generated during flight should have remained below the Coulombic level, although there was some ambiguity as to whether the loads in the mounting hardware exceeded the stick-slip threshold. At about the same time, Reference 10 provided data on spontaneous vibrations in a different, sub-scale model truss in 1-g testing. Heating the truss slowly while suspended in a convection heat chamber apparently induced these vibrations. Accelerations were observed with amplitudes between 0.1 and 1 g's and with frequencies between 1 and 18 kHz. Radiative heating induced spontaneous vibrations between 1 and 5 g's with frequencies between 9 and 18 kHz. These vibrations seemed to be limited in extent to local regions of the structure. Although there was no analysis of the induced loads provided in these experiments, the amplitudes of motion were estimated to be at the nanometer scale, and may therefore be evidence of thermally induced vibrations in a microslip load regime, but this remained an open question. This paper presents evidence and analysis of picometer scale spontaneous vibrations induced in the IPEX boom by a heterogeneous thermal load. These experiments were able to successfully induce vibrations by heating the region of one bay of the truss near the root. Several spontaneous vibrations were captured. Moreover, the vibrations show evidence of wave transmission and dispersion down the boom away from the area of the applied thermal load. An analysis is also presented. This analysis compares the kinetic energy of the vibration to a comparable release of strain energy in an individual, but unknown, truss member. It is shown that the energy of the vibrations was comparable to the energy that would have been released by the deformation of a truss member at similar amplitudes. All of these analyses support the notion that either frictional instability in a mechanism, or material instability in the truss was responsible for the observed vibrations. This paper is organized as follows: The first section presents the experimental apparatus and procedure including the configuration, test measurements and data acquisition. The second section summarizes the results of the tests including time and frequency domain characterization. The third section presents the analysis of the data and the comparison with possible sources of released strain energy. EXPERIMENTAL APPARATUS AND PROCEDURE

Incident review (IR) is a process for achieving a better understanding of problems related to the health and safety of clients and the integrity of healthcare facilities. The IR process ensures that the quality and the performance of care in a facility continue to be maintained and improved over time. Because of the practical realities of administrative and clinical care issues, the process of implementing IR and related interventions is often challenging. This paper examines the IR process and the barriers that affect and impede it.

That Decision Support Systems (DSS) should and do serve as agents for change in individual and organizational decision-making processes is a widely held position. There is less agreement, however, on whether or not DSS should deliberately try to influence the direction of the changes they cause. The panel examines the distinction between directed and nondirected change, debating the trade-offs among these two approaches and considering the likely course that practice will follow in the years ahead.

This paper presents a teaching model that has been used successfully in the MBA core course in information systems at several universities. The model is referred to as the "Information Technology Interaction Model" because it maintains that the consequences of information systems in organizations follow largely from the interaction of the technology with the organization and its environment. The model serves a number of pedagogical purposes: to integrate the various course components, to provide a formal foundation for the course content, to foster practical analytical skills, and to provide a framework for discussions and student projects. Moreover, the model is intended to acquaint students with the dynamics of information systems in organizations and to help them recognize the benefits, dangers, and limitations of these systems. The paper includes a discussion and examples of how the model can be used for proactive and reactive analyses, and it concludes with observations on the model's effectiveness in the core course.

In the course of interacting with a decision support system (DSS), decision makers may have numerous opportunities for exercising judgments. Some judgments pertain to what to do next; others require predictions or evaluations. Either deliberately or inadvertently, a DSS may guide its users in performing these judgments. This article lays a foundation and proposes an agenda for researching such "decisional guidance." Studying decisional guidance matters for two reasons. First, deliberately incorporating guidance in a system offers the potential of more supportive systems while raising a number of design questions. Second, understanding the consequences of guidance -- deliberate or not -- contributes to comprehending how DSSs affect decision-making behavior. This article examines three aspects of decisional guidance: (1) when and why system designers should provide decisional guidance, considering the opportunities, motives, and means for guiding; (2) how designers can provide guidance, introducing a three-dimensional typology for deliberate guidance; and (3) the consequences of decisional guidance -- that is, its effects and effectiveness. This article provides a coherent approach to a set of behavioral questions just now beginning to be addressed by researchers in a fragmented, tehnologically oriented manner.

Benign, soft-tissue masses of the hand are common. A vascular leiomyoma is an unusual tumor of smooth-muscle origin. In a 62-year-old man, the tumor arose from within a digital artery. Persistent symptoms prompted an excisional biopsy, requiring resection of a portion of the artery. Adequate collateral circulation preempted the need for a vascular graft. Vascular repair or grafting may be necessary if collateral circulation is not adequate.

Twenty of 59 hands (34%) of patients with carpal tunnel syndrome had abnormalities in sensibility testing of both median and ulnar nerves by either two-point discrimination, Semmes-Weinstein monofilament testing, or both. Before surgery, 53% of patients complained of paresthesias and/or numbness in ulnar nerve distribution. Eighty percent of the hands had abnormal Semmes-Weinstein monofilament testing of the ulnar nerve. Thirty-five percent had abnormal two-point discrimination. Forty-one percent had abnormal electromyographic testing of the ulnar nerve. All hands had median nerve decompression alone. Guyon's canal was not released. After surgery, 89% of patients had improvement in paresthesias and/or numbness of the ulnar nerve. Ninety-four percent had improvement in Semmes-Weinstein monofilament testing. Eighty-six percent had improvement in two-point discrimination. Patients with a residual abnormality in ulnar nerve sensibility also had continued abnormality in median nerve sensibility. A significant percentage of patients with carpal tunnel syndrome also have signs and symptoms of ulnar nerve compression. Most improved with carpal tunnel release alone.

Fourteen patients with 58 severe forearm muscle belly lacerations had muscle repair using tendon grafts. At mean follow-up of 14 months, results of manual muscle testing (N = 58) were: grade 5, 42%, grade 4, 14%, grade 3, 9%, grade 2, 9%, grade 1, 12%, and grade 0, 15%. Mean grip strength of the injured extremity, in pounds per square inch, was 33.5 compared with 83.4 on the noninjured side. Tendon excursion and joint mobility were maintained, and there were no postoperative complications. Tendon grafting of severe muscle lacerations is an effective method to overcome extensive defects.

A patient is described who postoperatively developed a clinical syndrome characteristic of toxic shock syndrome following amputation of a previously injured finger. A small stitch abscess was identified which grew Staphylococcus aureus. The patient became ill within 12 hours of surgery, suggesting that a small inoculum of a toxic shock-producing strain of S. aureus can produce the clinical syndrome.