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Radiation hardened new generation digital isolators have been developed. They use Analog Devices Inc. (ADI) iCoupler technology to provide high-speed, high accuracy, short-delay, low power, and more reliable rad hard isolators. In this paper, iCoupler technology structure is introduced in comparison with optocouplers, and three rad hard iCoupler products are presented along with radiation test results, including TID and heavy ion SEE test results.

The time-harmonic Discontinuous Galerkin Method (DGM) is a flexible forward solver for inverse scattering problems in electromagnetics. Standard DGM discretizations of Maxwell's curl equations, simultaneously solving for both electric and magnetic fields, are generally more accurate but less efficient than the DGM applied to the electric vector wave equation. A natural extension is to mix DGM formulations such that either the curl equation formulation or the wave equation formulation is locally adopted to preserve accuracy. Herein we present such a mixed DGM formulation for time-harmonic scattering problems, where the formulation choice is locally based on the presence of electric or magnetic constitutive parameters that differ from the background medium.

This paper presents a software architecture for Smart Buildings assets management which enables engineers to receive and update work orders and asset information using augmented reality and mobile technologies. The proposed architecture consists of a layered structure composed of three main modules for Building Management Systems (BMS); data collection, event management and enrichment, and asset and work order management. In this architecture we use the Message Queue Telemetry Transport protocol (MQTT) to exchange messages between the system components. Work orders and alerts are modelled using the Common Alert Protocol (CAP) and sent to the augmented reality application through the ITA Information fabric; a middleware component using MQTT augmented with policy, workflow and datastore. We describe the high-level architecture supporting the experimentation and services provision, access policies and security aspects of such an architecture. This architecture can encapsulate the system functionality, assure the interoperability between various component systems, integrate different data standards, and ease the maintenance, management and upgrading of building assets and service requests. The design of a smart building application based on this architecture is illustrated and experimentation results confirm the viability and efficiency of the proposed framework.

Many current brain-machine interfaces do not consider the behavioral context of the subject, rather, they assume the subject is constantly engaged in a single task. We investigated how incorporating information about state can improve the performance of a decoder. Unit spiking activity and LFPs were recorded from chronically implanted electrode arrays in primary motor and premotor corticies while a monkey performed a reach to grasp task. We applied an unsupervised clustering technique to LFP data to identify different neural states. Then, for each state, we fit a sparse Bayesian linear model with causal interaction terms to decode the joint kinematics of many degrees of freedom in the arm and hand. We used automatic relevance determination for variable selection and to avoid overfitting. We show that the state-based decoding model improves decoding performance over a model without state information. We further show that topology of interaction terms is different across different states.

This work describes how a fine-grained filtering Web service is generated using an extended XACML architecture for Data Providing Web Services (DPWSs). A DPWS is a Web service tasked with the retrieval of data that is annotated using a domain ontology. This work extends XACML policies to reference filtering classes from a filtering ontology instead of directly referencing fine-grained XML elements. This paper then contributes a language to state relations between the filtering ontology and the DPWS's domain ontology. It also contributes an algorithm to interpret these relations to determine if a given XML element from a DPWS is a member of a filtering class. This algorithm is then used by the extended XACML architecture to infer how a DPWS shall be filtered. This approach provides a clear separation of concerns between a DPWS's data domain and the filtering domain.

Animal identification and traceability have become increasingly important in the agriculture and food industry in recent decades mainly as a way to control quality and to manage animal health information and infectious diseases. Radio-frequency identification (RFID) technology has become the industry standard for managing livestock such as in dairy farms. Traditional herd management software has many deficiency and limitation. We propose a Web-based service oriented herd manage application by leveraging the emerging Web 2.0 technologies and an occasionally connected mobile database synchronization framework. This new architecture can provide improved accessibility, more up-to-date information and lower cost of ownership for the herd management software system. An initial prototype has been developed and tested on a three thousand cow dairy farm with encouraging result.

Data Providing Services (DPSs) have the sole purpose of retrieving data from existing sources according to their input parameters while also providing a semantic description of the data they provide using a parametrized view over a domain ontology. A layered model of viewing DPSs is proposed consisting of the data acquisition, syntactic and semantic layers. It is shown that by defining all three layers, a DPS may be generated and managed exclusively by its declarative definition. This will increase the agility and efficiency with which DPSs may be deployed and managed. As a development model, a set of reusable messages are created, these messages are to be semantically annotated using a view over the domain ontology and are syntactically represented such that they may be exported to XML Schema. These messages are used within the DPS definition where their views over the domain ontology are parametrized and the data acquisition layer is defined to acquire data from the source.

Removing boundaries between health care sub-domains has recently received increasing attention in both research and practice. Termed “silos”, traditional divisions in medicine are increasingly viewed as inefficient at a time when efficiency is essential. With a practical scenario as our basis, we review the use of a Data Providing Web Service (DPWS)-based framework to integrate data from multiple medical operations. A DPWS-based framework also addresses key software engineering requirements of our practical health care scenario such as the creation of a separation of concerns between the data source and the integration framework as well as the use of a domain ontology for describing the data that are accessible from the DPWSs. A separation of concerns gives full autonomy to each medical operation with regards to what information is exposed and with what controls (i.e. privacy and auditing). The domain ontology provides a common representation of data for all actors interacting with the framework which enhances the ability of the framework to handle distributed sources in addition to creating a consistent interface to continually evolving data sources.

The service oriented computing paradigm is transforming traditional enterprise information from a closed, centralized control system into a dynamic information exchange with business process support. In particular, interoperability of healthcare information systems has become an important issue within the healthcare industry. In order to enable effective and efficient information exchange, we propose a process oriented service discovery approach to support a dynamic healthcare service composition that is to occur during design time. Specifically, our approach utilizes semantic profiles to specify the semantic descriptions of process operations using domain specific ontologies such as HL7. Consequently, our methodology provides substantial flexibility for semantic healthcare service compositions while reusing existing processes and services.

Two partial helical dipole snakes were found to be able to overcome all imperfection and intrinsic spin resonances provided that the vertical betatron tunes were maintained in the spin tune gap near the integer 9. Recent vertical betatron tune scan showed that the two weak resonances at the beginning of the acceleration cycle may be the cause of polarization loss. This result has been confirmed by the vertical polarization profile measurement, and spin tracking simulations. Possible cure of the remaining beam polarization is discussed.

Gold ions for the 2007 run [1] of the relativistic heavy ion collider (RHIC) at Brookhaven National Laboratory (BNL) are accelerated in the Tandem,Booster and AGS prior to injection into RHIC. The setup and performance of this chain of accelerators is reviewed with a focus on improvements in the quality of beam delivered to RHIC. In particular,more uniform stripping foils between Booster and AGS,and a new bunch merging scheme in AGS have provided beam bunches with reduced longitudinal emittance for RHIC.

Dual partial snake scheme has provided polarized proton beams with 1.5 times 1011 intensity and 65% polarization for the relativistic heavy ion collider (RHIC) spin program. To overcome the residual polarization loss due to horizontal resonances in the Brookhaven alternating gradient synchrotron (AGS), a new string of quadrupoles have been added. The horizontal tune can then be set in the spin tune gap generated by the two partial snakes, such that horizontal resonances can also be avoided. This paper presents the accelerator setup and preliminary results.

Fixed target studies of small branching ratio decay processes require intense beams and smooth spills. Longitudinal structure arises through collective effects, well below the coasting beam stability threshold. These structures have been observed at the Brookhaven AGS and dependence on intensity and momentum spread measured. Measurements and amelioration techniques have been developed and will be described.

In this paper we will describe a data acquisition system designed and developed for the AGS Booster. The system was motivated by the need to get high quality beam diagnostics from the AGS Booster. This was accomplished by locating the electronics and digital data acquisition close to the Booster ring, to minimize loss of bandwidth in the original signals. In addition we had to develop the system rapidly and at a low cost. The system consists of a Lecroy digital oscilloscope which is interfaced through a National Instruments Lab View server application, developed for this project. This allows multiple client applications to time share the scope without interfering with each other. We will present a description of the system design along with example clients that we have implemented.

The Brookhaven AGS third integer resonant extraction system allows the AGS to provide high quality, high intensity 25.5 GeV/c proton beams simultaneously to four target stations and as many as 8 experiments. With the increasing intensities (over 7/spl times/10/sup 13/ protons/pulse) and associated longer spill periods (2.4 to 3 seconds long), we continue to run with low losses and high quality low modulation continuous current beams. We have an active program of high energy physics experiments, including the high precision measurement of the muons magnetic moment and the discovery of the rare Kaon decay, K/sup +/ /spl rarr/ /spl pi/ + /spl nu//spl nu/~. This program is continuing into the future with the rare symmetry violating process experiments currently being designed to operate at the AGS. In this paper we present results from operation of high intensity slow extraction, the problems we encounter, and our solutions to those problems.

The RHIC 2003 Physics Run required collisions between gold ions and deuterons. The injector necessarily had to deliver adequate quality (transverse and longitudinal emittance) and quantity of both species. For gold this was a continuing evolution from past work. For deuterons it was new territory. For the filling of the RHIC the injector not only had to deliver quality beams but also had to switch between these species quickly. This paper details the collider requirements and our success in meeting these. Some details of the configurations employed are given.

A fundamental aspect of particle physics is the spin of the particles. With polarized beams, the internal structure of the proton may be probed in ways that are unattainable with unpolarized beams. The Relativistic Heavy Ion Collider (RHIC) has the unique capability of colliding protons with both transverse and longitudinal polarization at center-of-mass energies up to 500 GeV. In this paper we examine the methods used to accelerate and manipulate polarized proton beams in RHIC and its injectors. Special techniques include the use of a partial Siberian snake and an ac dipole in the AGS. In RHIC we use four superconducting helical Siberian snakes (two per ring) for acceleration, and eight superconducting helical rotators for independent control of polarization directions at two interaction regions.

Polarized proton beam has been accelerated and stored at 100GeV in Relativistic Heavy Ion Collider (RHIC) to study spin effects in the hadronic reactions. The essential equipment includes four Siberian snakes and eight spin rotators in two RHIC rings, a partial snake in the AGS, fast relative polarimeters, and ac dipoles in the AGS and RHIC. This paper summarizes the performance of RHIC as a polarized proton collider and of AGS as the injector to RHIC.

As public and corporate interest in wireless solutions increases, the demand for consistent and acceptable quality of service for real-time, high-bandwidth data will also increase. Low bandwidths, high error rates, and transient traffic conditions are common in the wireless environment. These characteristics cause packet delay and loss, which negatively affect received quality. To improve the quality of audio transmission over wireless networks, we propose that audio applications adapt to current network conditions by reducing encoding rates to match available bandwidth. In this paper, we present the design and implementation of a source initiated adaptive audio application.

The Brookhaven AGS third integer resonant extraction system allows the AGS to provide high quality, high intensity 25.5 GeV/c proton beams simultaneously to four target stations and as many as 8 experiments. With the increasing intensities (over 7/spl times/10/sup 13/ protons/pulse) and associated longer spill periods (2.4 to 3 seconds long), we continue to run with low losses and high quality low modulation continuous current beams. Learning to extract and transport these higher intensity beams has required a process of careful modeling and experimentation. We have had to learn how to correct for various instabilities and how to better match extraction and the transport lines to the higher emittance beams being accelerated in the AGS. Techniques employed include "RF" methods to smooth out momentum distributions and fine structure. We will present results of detailed multi-particle tracking modeling studies which enabled us to develop a clear understanding of beam loss mechanisms in the transport and extraction process. We will report on our status, experiences, and the present understanding of the intensity limitations imposed by resonant extraction and transport to fixed target stations.

Using Verilog HDL and Synopsys, the digital signal processing of the AGS Transverse Damper was designed and fitted to an Altera Flex 10k FPGA. Using a control point specification style in the high level description greatly simplified the design by placing the burden of specifying the controller on the digital synthesizer. The basic design and low level simulation are presented as well as the design methodology.

The purpose of this new instrument is for probing beam halo and obtaining beam profiles of the resonant extracted beam at the AGS. The device described is a prototype version, to obtain data and prepare for a more permanent device. The goals of the permanent device are to allow emittances of low current, but high intensity slowly extracted beams to be accurately measured and to have a diagnostic for probing the wings of the beam distribution. The device works on secondary emission from thin targets as well as scattering into two scintillator telescopes. The targets are movable over the entire aperture at the device.

A method to split off a few percent of the 6x10/sup /spl and//13 AGS beam delivered to the slow external beam (SEB) lines and send it down the fast external beam line (FEB) has been developed. The mission is to feed a counter experiment off the FEB that directly measures the neutrino mass using the muon storage ring. The use of normal thin septum splitters would have an excessive loss overhead and been optically difficult. The AGS slow extraction uses a third integer resonance with sextupole strength so the resonance width is a few percent of the beam width. This results in a low density tail which will be clipped by a bent crystal and deflected into the FEB channel. This clipping off of the tail should reduce losses in the SEB transport line. Details of modelled orbits, particle distribution and extraction trajectories into and out off the crystal will be given.

Lime kilns are used as part of the chemical and energy recovery cycle in the pulp and paper industries. The control strategy is sensor based and uses in addition to the usual sensors, a single sided infrared mud moisture sensor and a CO and CO 2 flue gas analyzer for optimizing the kiln temperature profile, maximizing throughput, regulating the product quality and conforming to environmental regulations. A steady-state mathematical process model is also used to estimate the peak refractory temperature and predict the residual carbonate in the product. Control action is taken to prevent the peak refractory temperature from exceeding a preset limit, and to maintain the desired residual carbonate. The paper also discusses the simulation results from the mathematical model.