Method to Measure Total Noise Temperature of a Wireless Receiver During Operation

NASA Technical Reports Server (NTRS)

Young, Lawrence E. (Inventor); Esterhuizen, Stephan X. (Inventor); Turbiner, Dmitry (Inventor)

2014-01-01

An electromagnetic signal receiver and methods for determining the noise level and signal power in a signal of interest while the receiver is operating. In some embodiments, the signal of interest is a GPS signal. The receiver includes a noise source that provides a noise signal of known power during intervals while the signal of interest is observed. By measuring a signal-to-noise ratio for the signal of interest and the noise power in the signal of interest, the noise level and signal power of the signal of interest can be computed. Various methods of making the measurements and computing the power of the signal of interest are described. Applications of the system and method are described.

40 CFR 86.010-2 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... diagnostics, means verifying that a component and/or system that receives information from a control computer... maintained. In general, limp-home operation implies that a component or system is not operating properly or... cannot be erased through human interaction with the OBD system or any onboard computer. Potential...

40 CFR 86.010-2 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... diagnostics, means verifying that a component and/or system that receives information from a control computer... maintained. In general, limp-home operation implies that a component or system is not operating properly or... cannot be erased through human interaction with the OBD system or any onboard computer. Potential...

40 CFR 86.010-2 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... diagnostics, means verifying that a component and/or system that receives information from a control computer... maintained. In general, limp-home operation implies that a component or system is not operating properly or... cannot be erased through human interaction with the OBD system or any onboard computer. Potential...

40 CFR 86.010-2 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... diagnostics, means verifying that a component and/or system that receives information from a control computer... maintained. In general, limp-home operation implies that a component or system is not operating properly or... cannot be erased through human interaction with the OBD system or any onboard computer. Potential...

40 CFR 86.010-2 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... diagnostics, means verifying that a component and/or system that receives information from a control computer... maintained. In general, limp-home operation implies that a component or system is not operating properly or... cannot be erased through human interaction with the OBD system or any onboard computer. Potential...

High-speed on-chip windowed centroiding using photodiode-based CMOS imager

NASA Technical Reports Server (NTRS)

Pain, Bedabrata (Inventor); Sun, Chao (Inventor); Yang, Guang (Inventor); Cunningham, Thomas J. (Inventor); Hancock, Bruce (Inventor)

2003-01-01

A centroid computation system is disclosed. The system has an imager array, a switching network, computation elements, and a divider circuit. The imager array has columns and rows of pixels. The switching network is adapted to receive pixel signals from the image array. The plurality of computation elements operates to compute inner products for at least x and y centroids. The plurality of computation elements has only passive elements to provide inner products of pixel signals the switching network. The divider circuit is adapted to receive the inner products and compute the x and y centroids.

High-speed on-chip windowed centroiding using photodiode-based CMOS imager

NASA Technical Reports Server (NTRS)

Pain, Bedabrata (Inventor); Sun, Chao (Inventor); Yang, Guang (Inventor); Cunningham, Thomas J. (Inventor); Hancock, Bruce (Inventor)

2004-01-01

A centroid computation system is disclosed. The system has an imager array, a switching network, computation elements, and a divider circuit. The imager array has columns and rows of pixels. The switching network is adapted to receive pixel signals from the image array. The plurality of computation elements operates to compute inner products for at least x and y centroids. The plurality of computation elements has only passive elements to provide inner products of pixel signals the switching network. The divider circuit is adapted to receive the inner products and compute the x and y centroids.

Executing scatter operation to parallel computer nodes by repeatedly broadcasting content of send buffer partition corresponding to each node upon bitwise OR operation

DOEpatents

Archer, Charles J [Rochester, MN; Ratterman, Joseph D [Rochester, MN

2009-11-06

Executing a scatter operation on a parallel computer includes: configuring a send buffer on a logical root, the send buffer having positions, each position corresponding to a ranked node in an operational group of compute nodes and for storing contents scattered to that ranked node; and repeatedly for each position in the send buffer: broadcasting, by the logical root to each of the other compute nodes on a global combining network, the contents of the current position of the send buffer using a bitwise OR operation, determining, by each compute node, whether the current position in the send buffer corresponds with the rank of that compute node, if the current position corresponds with the rank, receiving the contents and storing the contents in a reception buffer of that compute node, and if the current position does not correspond with the rank, discarding the contents.

Send-side matching of data communications messages

DOEpatents

Archer, Charles J.; Blocksome, Michael A.; Ratterman, Joseph D.; Smith, Brian E.

2014-07-01

Send-side matching of data communications messages includes a plurality of compute nodes organized for collective operations, including: issuing by a receiving node to source nodes a receive message that specifies receipt of a single message to be sent from any source node, the receive message including message matching information, a specification of a hardware-level mutual exclusion device, and an identification of a receive buffer; matching by two or more of the source nodes the receive message with pending send messages in the two or more source nodes; operating by one of the source nodes having a matching send message the mutual exclusion device, excluding messages from other source nodes with matching send messages and identifying to the receiving node the source node operating the mutual exclusion device; and sending to the receiving node from the source node operating the mutual exclusion device a matched pending message.

Eigen Spreading

DTIC Science & Technology

2008-02-27

between the PHY layer and for example a host PC computer . The PC wants to generate and receive a sequence of data packets. The PC may also want to send...the testbed is quite similar. Given the intense computational requirements of SVD and other matrix mode operations needed to support eigen spreading a...platform for real time operation. This task is probably the major challenge in the development of the testbed. All compute intensive tasks will be

MURI: Optimal Quantum Dynamic Discrimination of Chemical and Biological Agents

DTIC Science & Technology

2008-06-12

multiparameter) Hilbert space for enhanced detection and classification: an application of receiver operating curve statistics to laser-based mass...Adaptive reshaping of objects in (multiparameter) Hilbert space for enhanced detection and classification: an application of receiver operating curve...Doctoral Associate Muhannad Zamari, Graduate Student Ilya Greenberg , Computer Consultant Getahun Menkir, Graduate Student Lalinda Palliyaguru, Graduate

Measuring radio-signal power accurately

NASA Technical Reports Server (NTRS)

Goldstein, R. M.; Newton, J. W.; Winkelstein, R. A.

1979-01-01

Absolute value of signal power in weak radio signals is determined by computer-aided measurements. Equipment operates by averaging received signal over several-minute period and comparing average value with noise level of receiver previously calibrated.

Determining collective barrier operation skew in a parallel computer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Faraj, Daniel A.

2015-11-24

Determining collective barrier operation skew in a parallel computer that includes a number of compute nodes organized into an operational group includes: for each of the nodes until each node has been selected as a delayed node: selecting one of the nodes as a delayed node; entering, by each node other than the delayed node, a collective barrier operation; entering, after a delay by the delayed node, the collective barrier operation; receiving an exit signal from a root of the collective barrier operation; and measuring, for the delayed node, a barrier completion time. The barrier operation skew is calculated by:more » identifying, from the compute nodes' barrier completion times, a maximum barrier completion time and a minimum barrier completion time and calculating the barrier operation skew as the difference of the maximum and the minimum barrier completion time.« less

Determining collective barrier operation skew in a parallel computer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Faraj, Daniel A.

Determining collective barrier operation skew in a parallel computer that includes a number of compute nodes organized into an operational group includes: for each of the nodes until each node has been selected as a delayed node: selecting one of the nodes as a delayed node; entering, by each node other than the delayed node, a collective barrier operation; entering, after a delay by the delayed node, the collective barrier operation; receiving an exit signal from a root of the collective barrier operation; and measuring, for the delayed node, a barrier completion time. The barrier operation skew is calculated by:more » identifying, from the compute nodes' barrier completion times, a maximum barrier completion time and a minimum barrier completion time and calculating the barrier operation skew as the difference of the maximum and the minimum barrier completion time.« less

Executing a gather operation on a parallel computer

DOEpatents

Archer, Charles J [Rochester, MN; Ratterman, Joseph D [Rochester, MN

2012-03-20

Methods, apparatus, and computer program products are disclosed for executing a gather operation on a parallel computer according to embodiments of the present invention. Embodiments include configuring, by the logical root, a result buffer or the logical root, the result buffer having positions, each position corresponding to a ranked node in the operational group and for storing contribution data gathered from that ranked node. Embodiments also include repeatedly for each position in the result buffer: determining, by each compute node of an operational group, whether the current position in the result buffer corresponds with the rank of the compute node, if the current position in the result buffer corresponds with the rank of the compute node, contributing, by that compute node, the compute node's contribution data, if the current position in the result buffer does not correspond with the rank of the compute node, contributing, by that compute node, a value of zero for the contribution data, and storing, by the logical root in the current position in the result buffer, results of a bitwise OR operation of all the contribution data by all compute nodes of the operational group for the current position, the results received through the global combining network.

40 CFR 721.91 - Computation of estimated surface water concentrations: Instructions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... shall be computed for each site using the stream flow rate appropriate for the site according to... computing the equation, the number of kilograms released, and receiving stream flow. (a) Number of kilograms... diagram which describes each manufacturing, processing, or use operation involving the substance. The...

40 CFR 721.91 - Computation of estimated surface water concentrations: Instructions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... shall be computed for each site using the stream flow rate appropriate for the site according to... computing the equation, the number of kilograms released, and receiving stream flow. (a) Number of kilograms... diagram which describes each manufacturing, processing, or use operation involving the substance. The...

Low Computational Signal Acquisition for GNSS Receivers Using a Resampling Strategy and Variable Circular Correlation Time

PubMed Central

Zhang, Yeqing; Wang, Meiling; Li, Yafeng

2018-01-01

For the objective of essentially decreasing computational complexity and time consumption of signal acquisition, this paper explores a resampling strategy and variable circular correlation time strategy specific to broadband multi-frequency GNSS receivers. In broadband GNSS receivers, the resampling strategy is established to work on conventional acquisition algorithms by resampling the main lobe of received broadband signals with a much lower frequency. Variable circular correlation time is designed to adapt to different signal strength conditions and thereby increase the operation flexibility of GNSS signal acquisition. The acquisition threshold is defined as the ratio of the highest and second highest correlation results in the search space of carrier frequency and code phase. Moreover, computational complexity of signal acquisition is formulated by amounts of multiplication and summation operations in the acquisition process. Comparative experiments and performance analysis are conducted on four sets of real GPS L2C signals with different sampling frequencies. The results indicate that the resampling strategy can effectively decrease computation and time cost by nearly 90–94% with just slight loss of acquisition sensitivity. With circular correlation time varying from 10 ms to 20 ms, the time cost of signal acquisition has increased by about 2.7–5.6% per millisecond, with most satellites acquired successfully. PMID:29495301

Low Computational Signal Acquisition for GNSS Receivers Using a Resampling Strategy and Variable Circular Correlation Time.

PubMed

Zhang, Yeqing; Wang, Meiling; Li, Yafeng

2018-02-24

For the objective of essentially decreasing computational complexity and time consumption of signal acquisition, this paper explores a resampling strategy and variable circular correlation time strategy specific to broadband multi-frequency GNSS receivers. In broadband GNSS receivers, the resampling strategy is established to work on conventional acquisition algorithms by resampling the main lobe of received broadband signals with a much lower frequency. Variable circular correlation time is designed to adapt to different signal strength conditions and thereby increase the operation flexibility of GNSS signal acquisition. The acquisition threshold is defined as the ratio of the highest and second highest correlation results in the search space of carrier frequency and code phase. Moreover, computational complexity of signal acquisition is formulated by amounts of multiplication and summation operations in the acquisition process. Comparative experiments and performance analysis are conducted on four sets of real GPS L2C signals with different sampling frequencies. The results indicate that the resampling strategy can effectively decrease computation and time cost by nearly 90-94% with just slight loss of acquisition sensitivity. With circular correlation time varying from 10 ms to 20 ms, the time cost of signal acquisition has increased by about 2.7-5.6% per millisecond, with most satellites acquired successfully.

Providing full point-to-point communications among compute nodes of an operational group in a global combining network of a parallel computer

DOEpatents

Archer, Charles J; Faraj, Ahmad A; Inglett, Todd A; Ratterman, Joseph D

2013-04-16

Methods, apparatus, and products are disclosed for providing full point-to-point communications among compute nodes of an operational group in a global combining network of a parallel computer, each compute node connected to each adjacent compute node in the global combining network through a link, that include: receiving a network packet in a compute node, the network packet specifying a destination compute node; selecting, in dependence upon the destination compute node, at least one of the links for the compute node along which to forward the network packet toward the destination compute node; and forwarding the network packet along the selected link to the adjacent compute node connected to the compute node through the selected link.

A micro-computer based system to compute magnetic variation

NASA Technical Reports Server (NTRS)

Kaul, R.

1984-01-01

A mathematical model of magnetic variation in the continental United States (COT48) was implemented in the Ohio University LORAN C receiver. The model is based on a least squares fit of a polynomial function. The implementation on the microprocessor based LORAN C receiver is possible with the help of a math chip, Am9511 which performs 32 bit floating point mathematical operations. A Peripheral Interface Adapter (M6520) is used to communicate between the 6502 based micro-computer and the 9511 math chip. The implementation provides magnetic variation data to the pilot as a function of latitude and longitude. The model and the real time implementation in the receiver are described.

Automatic Thermal Infrared Panoramic Imaging Sensor

DTIC Science & Technology

2006-11-01

hibernation, in which power supply to the server computer , the wireless network hardware, the GPS receiver, and the electronic compass / tilt sensor...prototype. At the operator’s command on the client laptop, the receiver wakeup device on the server side will switch on the ATX power supply at the...server, to resume the power supply to all the APTIS components. The embedded computer will resume all of the functions it was performing when put

Development of wide band digital receiver for atmospheric radars using COTS board based SDR

NASA Astrophysics Data System (ADS)

Yasodha, Polisetti; Jayaraman, Achuthan; Thriveni, A.

2016-07-01

Digital receiver extracts the received echo signal information, and is a potential subsystem for atmospheric radar, also referred to as wind profiling radar (WPR), which provides the vertical profiles of 3-dimensional wind vector in the atmosphere. This paper presents the development of digital receiver using COTS board based Software Defined Radio technique, which can be used for atmospheric radars. The developmental work is being carried out at National Atmospheric Research Laboratory (NARL), Gadanki. The digital receiver consists of a commercially available software defined radio (SDR) board called as universal software radio peripheral B210 (USRP B210) and a personal computer. USRP B210 operates over a wider frequency range from 70 MHz to 6 GHz and hence can be used for variety of radars like Doppler weather radars operating in S/C bands, in addition to wind profiling radars operating in VHF, UHF and L bands. Due to the flexibility and re-configurability of SDR, where the component functionalities are implemented in software, it is easy to modify the software to receive the echoes and process them as per the requirement suitable for the type of the radar intended. Hence, USRP B210 board along with the computer forms a versatile digital receiver from 70 MHz to 6 GHz. It has an inbuilt direct conversion transceiver with two transmit and two receive channels, which can be operated in fully coherent 2x2 MIMO fashion and thus it can be used as a two channel receiver. Multiple USRP B210 boards can be synchronized using the pulse per second (PPS) input provided on the board, to configure multi-channel digital receiver system. RF gain of the transceiver can be varied from 0 to 70 dB. The board can be controlled from the computer via USB 3.0 interface through USRP hardware driver (UHD), which is an open source cross platform driver. The USRP B210 board is connected to the personal computer through USB 3.0. Reference (10 MHz) clock signal from the radar master oscillator is used to lock the board, which is essential for deriving Doppler information. Input from the radar analog receiver is given to one channel of USRP B210, which is down converted to baseband. 12-bit ADC present on the board digitizes the signal and produces I (in-phase) and Q (quadrature-phase) data. The maximum sampling rate possible is about 61 MSPS. The I and Q (time series) data is sent to PC via USB 3.0, where the signal processing is carried out. The online processing steps include decimation, range gating, decoding, coherent integration and FFT computation (optional). The processed data is then stored in the hard disk. C++ programming language is used for developing the real time signal processing. Shared memory along with multi threading is used to collect and process data simultaneously. Before implementing the real time operation, stand alone test of the board was carried out through GNU radio software and the base band output data obtained is found satisfactory. Later the board is integrated with the existing Lower Atmospheric Wind Profiling radar at NARL. The radar receive IF output at 70 MHz is given to the board and the real-time radar data is collected. The data is processed off-line and the range-doppler spectrum is obtained. Online processing software is under progress.

Jackknife variance of the partial area under the empirical receiver operating characteristic curve.

PubMed

Bandos, Andriy I; Guo, Ben; Gur, David

2017-04-01

Receiver operating characteristic analysis provides an important methodology for assessing traditional (e.g., imaging technologies and clinical practices) and new (e.g., genomic studies, biomarker development) diagnostic problems. The area under the clinically/practically relevant part of the receiver operating characteristic curve (partial area or partial area under the receiver operating characteristic curve) is an important performance index summarizing diagnostic accuracy at multiple operating points (decision thresholds) that are relevant to actual clinical practice. A robust estimate of the partial area under the receiver operating characteristic curve is provided by the area under the corresponding part of the empirical receiver operating characteristic curve. We derive a closed-form expression for the jackknife variance of the partial area under the empirical receiver operating characteristic curve. Using the derived analytical expression, we investigate the differences between the jackknife variance and a conventional variance estimator. The relative properties in finite samples are demonstrated in a simulation study. The developed formula enables an easy way to estimate the variance of the empirical partial area under the receiver operating characteristic curve, thereby substantially reducing the computation burden, and provides important insight into the structure of the variability. We demonstrate that when compared with the conventional approach, the jackknife variance has substantially smaller bias, and leads to a more appropriate type I error rate of the Wald-type test. The use of the jackknife variance is illustrated in the analysis of a data set from a diagnostic imaging study.

Providing full point-to-point communications among compute nodes of an operational group in a global combining network of a parallel computer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Archer, Charles J.; Faraj, Daniel A.; Inglett, Todd A.

Methods, apparatus, and products are disclosed for providing full point-to-point communications among compute nodes of an operational group in a global combining network of a parallel computer, each compute node connected to each adjacent compute node in the global combining network through a link, that include: receiving a network packet in a compute node, the network packet specifying a destination compute node; selecting, in dependence upon the destination compute node, at least one of the links for the compute node along which to forward the network packet toward the destination compute node; and forwarding the network packet along the selectedmore » link to the adjacent compute node connected to the compute node through the selected link.« less

Chaining direct memory access data transfer operations for compute nodes in a parallel computer

DOEpatents

Archer, Charles J.; Blocksome, Michael A.

2010-09-28

Methods, systems, and products are disclosed for chaining DMA data transfer operations for compute nodes in a parallel computer that include: receiving, by an origin DMA engine on an origin node in an origin injection FIFO buffer for the origin DMA engine, a RGET data descriptor specifying a DMA transfer operation data descriptor on the origin node and a second RGET data descriptor on the origin node, the second RGET data descriptor specifying a target RGET data descriptor on the target node, the target RGET data descriptor specifying an additional DMA transfer operation data descriptor on the origin node; creating, by the origin DMA engine, an RGET packet in dependence upon the RGET data descriptor, the RGET packet containing the DMA transfer operation data descriptor and the second RGET data descriptor; and transferring, by the origin DMA engine to a target DMA engine on the target node, the RGET packet.

Joint remote control of an arbitrary single-qubit state by using a multiparticle entangled state as the quantum channel

NASA Astrophysics Data System (ADS)

Lv, Shu-Xin; Zhao, Zheng-Wei; Zhou, Ping

2018-01-01

We present a scheme for joint remote implementation of an arbitrary single-qubit operation following some ideas in one-way quantum computation. All the senders share the information of implemented quantum operation and perform corresponding single-qubit measurements according to their information of implemented operation. An arbitrary single-qubit operation can be implemented upon the remote receiver's quantum system if the receiver cooperates with all the senders. Moreover, we study the protocol of multiparty joint remote implementation of an arbitrary single-qubit operation with many senders by using a multiparticle entangled state as the quantum channel.

Remote media vision-based computer input device

NASA Astrophysics Data System (ADS)

Arabnia, Hamid R.; Chen, Ching-Yi

1991-11-01

In this paper, we introduce a vision-based computer input device which has been built at the University of Georgia. The user of this system gives commands to the computer without touching any physical device. The system receives input through a CCD camera; it is PC- based and is built on top of the DOS operating system. The major components of the input device are: a monitor, an image capturing board, a CCD camera, and some software (developed by use). These are interfaced with a standard PC running under the DOS operating system.

Internal controls over computer-processed financial data at Boeing Petroleum Services

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1992-02-14

The Strategic Petroleum Reserve (SPR) is responsible for purchasing and storing crude oil to mitigate the potential adverse impact of any future disruptions in crude oil imports. Boeing Petroleum Services, Inc. (BPS) operates the SPR under a US Department of Energy (DOE) management and operating contract. BPS receives support for various information systems and other information processing needs from a mainframe computer center. The objective of the audit was to determine if the internal controls implemented by BPS for computer systems were adequate to assure processing reliability.

Remote direct memory access

DOEpatents

Archer, Charles J.; Blocksome, Michael A.

2012-12-11

Methods, parallel computers, and computer program products are disclosed for remote direct memory access. Embodiments include transmitting, from an origin DMA engine on an origin compute node to a plurality target DMA engines on target compute nodes, a request to send message, the request to send message specifying a data to be transferred from the origin DMA engine to data storage on each target compute node; receiving, by each target DMA engine on each target compute node, the request to send message; preparing, by each target DMA engine, to store data according to the data storage reference and the data length, including assigning a base storage address for the data storage reference; sending, by one or more of the target DMA engines, an acknowledgment message acknowledging that all the target DMA engines are prepared to receive a data transmission from the origin DMA engine; receiving, by the origin DMA engine, the acknowledgement message from the one or more of the target DMA engines; and transferring, by the origin DMA engine, data to data storage on each of the target compute nodes according to the data storage reference using a single direct put operation.

49 CFR 37.187 - Interline service.

Code of Federal Regulations, 2011 CFR

2011-10-01

... to Point C. By immediate communication, we mean that the ticket or reservation agent for Operator X, by phone, fax, computer, or other instantaneous means, contacts Operator Y the minute the reservation... service shall ensure that they have the capacity to receive communications at all times concerning...

49 CFR 37.187 - Interline service.

Code of Federal Regulations, 2012 CFR

2012-10-01

... to Point C. By immediate communication, we mean that the ticket or reservation agent for Operator X, by phone, fax, computer, or other instantaneous means, contacts Operator Y the minute the reservation... service shall ensure that they have the capacity to receive communications at all times concerning...

49 CFR 37.187 - Interline service.

Code of Federal Regulations, 2013 CFR

2013-10-01

... to Point C. By immediate communication, we mean that the ticket or reservation agent for Operator X, by phone, fax, computer, or other instantaneous means, contacts Operator Y the minute the reservation... service shall ensure that they have the capacity to receive communications at all times concerning...

Endpoint-based parallel data processing in a parallel active messaging interface of a parallel computer

DOEpatents

Archer, Charles J.; Blocksome, Michael A.; Ratterman, Joseph D.; Smith, Brian E.

2014-08-12

Endpoint-based parallel data processing in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI composed of data communications endpoints, each endpoint including a specification of data communications parameters for a thread of execution on a compute node, including specifications of a client, a context, and a task, the compute nodes coupled for data communications through the PAMI, including establishing a data communications geometry, the geometry specifying, for tasks representing processes of execution of the parallel application, a set of endpoints that are used in collective operations of the PAMI including a plurality of endpoints for one of the tasks; receiving in endpoints of the geometry an instruction for a collective operation; and executing the instruction for a collective operation through the endpoints in dependence upon the geometry, including dividing data communications operations among the plurality of endpoints for one of the tasks.

Bootstrap-based procedures for inference in nonparametric receiver-operating characteristic curve regression analysis.

PubMed

Rodríguez-Álvarez, María Xosé; Roca-Pardiñas, Javier; Cadarso-Suárez, Carmen; Tahoces, Pablo G

2018-03-01

Prior to using a diagnostic test in a routine clinical setting, the rigorous evaluation of its diagnostic accuracy is essential. The receiver-operating characteristic curve is the measure of accuracy most widely used for continuous diagnostic tests. However, the possible impact of extra information about the patient (or even the environment) on diagnostic accuracy also needs to be assessed. In this paper, we focus on an estimator for the covariate-specific receiver-operating characteristic curve based on direct regression modelling and nonparametric smoothing techniques. This approach defines the class of generalised additive models for the receiver-operating characteristic curve. The main aim of the paper is to offer new inferential procedures for testing the effect of covariates on the conditional receiver-operating characteristic curve within the above-mentioned class. Specifically, two different bootstrap-based tests are suggested to check (a) the possible effect of continuous covariates on the receiver-operating characteristic curve and (b) the presence of factor-by-curve interaction terms. The validity of the proposed bootstrap-based procedures is supported by simulations. To facilitate the application of these new procedures in practice, an R-package, known as npROCRegression, is provided and briefly described. Finally, data derived from a computer-aided diagnostic system for the automatic detection of tumour masses in breast cancer is analysed.

Spectrum/Orbit-Utilization Program

NASA Technical Reports Server (NTRS)

Miller, Edward F.; Sawitz, Paul; Zusman, Fred

1988-01-01

Interferences among geostationary satellites determine allocations. Spectrum/Orbit Utilization Program (SOUP) is analytical computer program for determining mutual interferences among geostationary-satellite communication systems operating in given scenario. Major computed outputs are carrier-to-interference ratios at receivers at specified stations on Earth. Information enables determination of acceptability of planned communication systems. Written in FORTRAN.

A micro-computer-based system to compute magnetic variation

NASA Technical Reports Server (NTRS)

Kaul, Rajan

1987-01-01

A mathematical model of magnetic variation in the continental United States was implemented in the Ohio University Loran-C receiver. The model is based on a least squares fit of a polynomial function. The implementation on the microprocessor based Loran-C receiver is possible with the help of a math chip which performs 32 bit floating point mathematical operations. A Peripheral Interface Adapter is used to communicate between the 6502 based microcomputer and the 9511 math chip. The implementation provides magnetic variation data to the pilot as a function of latitude and longitude. The model and the real time implementation in the receiver are described.

Complementary code and digital filtering for detection of weak VHF radar signals from the mesoscale. [SOUSY-VHF radar, Harz Mountains, Germany

NASA Technical Reports Server (NTRS)

Schmidt, G.; Ruster, R.; Czechowsky, P.

1983-01-01

The SOUSY-VHF-Radar operates at a frequency of 53.5 MHz in a valley in the Harz mountains, Germany, 90 km from Hanover. The radar controller, which is programmed by a 16-bit computer holds 1024 program steps in core and controls, via 8 channels, the whole radar system: in particular the master oscillator, the transmitter, the transmit-receive-switch, the receiver, the analog to digital converter, and the hardware adder. The high-sensitivity receiver has a dynamic range of 70 dB and a video bandwidth of 1 MHz. Phase coding schemes are applied, in particular for investigations at mesospheric heights, in order to carry out measurements with the maximum duty cycle and the maximum height resolution. The computer takes the data from the adder to store it in magnetic tape or disc. The radar controller is programmed by the computer using simple FORTRAN IV statements. After the program has been loaded and the computer has started the radar controller, it runs automatically, stopping at the program end. In case of errors or failures occurring during the radar operation, the radar controller is shut off caused either by a safety circuit or by a power failure circuit or by a parity check system.

The application of rapid prototyping technique in chin augmentation.

PubMed

Li, Min; Lin, Xin; Xu, Yongchen

2010-04-01

This article discusses the application of computer-aided design and rapid prototyping techniques in prosthetic chin augmentation for mild microgenia. Nine cases of mild microgenia underwent an electrobeam computer tomography scan. Then we performed three-dimensional reconstruction and operative design using computer software. According to the design, we determined the shape and size of the prostheses and made an individualized prosthesis for each chin augmentation with the rapid prototyping technique. With the application of computer-aided design and a rapid prototyping technique, we could determine the shape, size, and embedding location accurately. Prefabricating the individual prosthesis model is useful in improving the accuracy of treatment. In the nine cases of mild microgenia, three received a silicone implant, four received an ePTFE implant, and two received a Medpor implant. All patients were satisfied with the results. During follow-up at 6-12 months, all patients remained satisfied. The application of computer-aided design and rapid prototyping techniques can offer surgeons the ability to design an individualized ideal prosthesis for each patient.

The use of LANDSAT DCS and imagery in reservoir management and operation. [New England

NASA Technical Reports Server (NTRS)

Cooper, S. (Principal Investigator)

1976-01-01

The author has identified the following significant results. A tally of DCP messages received shows that the number of messages increased markedly at the beginning of the year as the downlink went into operation, but dropped off in May due to computer troubles.

Use of an Interactive General-Purpose Computer Terminal to Simulate Training Equipment Operation.

ERIC Educational Resources Information Center

Lahey, George F.; And Others

Trainees from Navy Basic Electricity/Electronics School were assigned to receive either computer-assisted instruction (CAI) or conventional individualized instruction in a segment of a course requiring use of a multimeter to measure resistance and current flow. The (CAI) group used PLATO IV plasma-screen terminals; individualized instruction…

Logo Burn-In. Microcomputing Working Paper Series.

ERIC Educational Resources Information Center

Drexel Univ., Philadelphia, PA. Microcomputing Program.

This paper describes a hot-stamping operation undertaken at Drexel University in an attempt to prevent computer theft on campus. The program was initiated in response to the University's anticipated receipt of up to 3,000 Macintosh microcomputers per year and the consequent publicity the university was receiving. All clusters of computers (e.g.,…

Profiling an application for power consumption during execution on a compute node

DOEpatents

Archer, Charles J; Blocksome, Michael A; Peters, Amanda E; Ratterman, Joseph D; Smith, Brian E

2013-09-17

Methods, apparatus, and products are disclosed for profiling an application for power consumption during execution on a compute node that include: receiving an application for execution on a compute node; identifying a hardware power consumption profile for the compute node, the hardware power consumption profile specifying power consumption for compute node hardware during performance of various processing operations; determining a power consumption profile for the application in dependence upon the application and the hardware power consumption profile for the compute node; and reporting the power consumption profile for the application.

Web-based multi-channel analyzer

DOEpatents

Gritzo, Russ E.

2003-12-23

The present invention provides an improved multi-channel analyzer designed to conveniently gather, process, and distribute spectrographic pulse data. The multi-channel analyzer may operate on a computer system having memory, a processor, and the capability to connect to a network and to receive digitized spectrographic pulses. The multi-channel analyzer may have a software module integrated with a general-purpose operating system that may receive digitized spectrographic pulses for at least 10,000 pulses per second. The multi-channel analyzer may further have a user-level software module that may receive user-specified controls dictating the operation of the multi-channel analyzer, making the multi-channel analyzer customizable by the end-user. The user-level software may further categorize and conveniently distribute spectrographic pulse data employing non-proprietary, standard communication protocols and formats.

Waste receiving and processing plant control system; system design description

DOE Office of Scientific and Technical Information (OSTI.GOV)

LANE, M.P.

1999-02-24

The Plant Control System (PCS) is a heterogeneous computer system composed of numerous sub-systems. The PCS represents every major computer system that is used to support operation of the Waste Receiving and Processing (WRAP) facility. This document, the System Design Description (PCS SDD), includes several chapters and appendices. Each chapter is devoted to a separate PCS sub-system. Typically, each chapter includes an overview description of the system, a list of associated documents related to operation of that system, and a detailed description of relevant system features. Each appendice provides configuration information for selected PCS sub-systems. The appendices are designed asmore » separate sections to assist in maintaining this document due to frequent changes in system configurations. This document is intended to serve as the primary reference for configuration of PCS computer systems. The use of this document is further described in the WRAP System Configuration Management Plan, WMH-350, Section 4.1.« less

Adaptive reconfigurable V-BLAST type equalizer for cognitive MIMO-OFDM radios

NASA Astrophysics Data System (ADS)

Ozden, Mehmet Tahir

2015-12-01

An adaptive channel shortening equalizer design for multiple input multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) radio receivers is considered in this presentation. The proposed receiver has desirable features for cognitive and software defined radio implementations. It consists of two sections: MIMO decision feedback equalizer (MIMO-DFE) and adaptive multiple Viterbi detection. In MIMO-DFE section, a complete modified Gram-Schmidt orthogonalization of multichannel input data is accomplished using sequential processing multichannel Givens lattice stages, so that a Vertical Bell Laboratories Layered Space Time (V-BLAST) type MIMO-DFE is realized at the front-end section of the channel shortening equalizer. Matrix operations, a major bottleneck for receiver operations, are accordingly avoided, and only scalar operations are used. A highly modular and regular radio receiver architecture that has a suitable structure for digital signal processing (DSP) chip and field programable gate array (FPGA) implementations, which are important for software defined radio realizations, is achieved. The MIMO-DFE section of the proposed receiver can also be reconfigured for spectrum sensing and positioning functions, which are important tasks for cognitive radio applications. In connection with adaptive multiple Viterbi detection section, a systolic array implementation for each channel is performed so that a receiver architecture with high computational concurrency is attained. The total computational complexity is given in terms of equalizer and desired response filter lengths, alphabet size, and number of antennas. The performance of the proposed receiver is presented for two-channel case by means of mean squared error (MSE) and probability of error evaluations, which are conducted for time-invariant and time-variant channel conditions, orthogonal and nonorthogonal transmissions, and two different modulation schemes.

Shared address collectives using counter mechanisms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blocksome, Michael; Dozsa, Gabor; Gooding, Thomas M

A shared address space on a compute node stores data received from a network and data to transmit to the network. The shared address space includes an application buffer that can be directly operated upon by a plurality of processes, for instance, running on different cores on the compute node. A shared counter is used for one or more of signaling arrival of the data across the plurality of processes running on the compute node, signaling completion of an operation performed by one or more of the plurality of processes, obtaining reservation slots by one or more of the pluralitymore » of processes, or combinations thereof.« less

Quantum attack-resistent certificateless multi-receiver signcryption scheme.

PubMed

Li, Huixian; Chen, Xubao; Pang, Liaojun; Shi, Weisong

2013-01-01

The existing certificateless signcryption schemes were designed mainly based on the traditional public key cryptography, in which the security relies on the hard problems, such as factor decomposition and discrete logarithm. However, these problems will be easily solved by the quantum computing. So the existing certificateless signcryption schemes are vulnerable to the quantum attack. Multivariate public key cryptography (MPKC), which can resist the quantum attack, is one of the alternative solutions to guarantee the security of communications in the post-quantum age. Motivated by these concerns, we proposed a new construction of the certificateless multi-receiver signcryption scheme (CLMSC) based on MPKC. The new scheme inherits the security of MPKC, which can withstand the quantum attack. Multivariate quadratic polynomial operations, which have lower computation complexity than bilinear pairing operations, are employed in signcrypting a message for a certain number of receivers in our scheme. Security analysis shows that our scheme is a secure MPKC-based scheme. We proved its security under the hardness of the Multivariate Quadratic (MQ) problem and its unforgeability under the Isomorphism of Polynomials (IP) assumption in the random oracle model. The analysis results show that our scheme also has the security properties of non-repudiation, perfect forward secrecy, perfect backward secrecy and public verifiability. Compared with the existing schemes in terms of computation complexity and ciphertext length, our scheme is more efficient, which makes it suitable for terminals with low computation capacity like smart cards.

CONC/11: A computer program for calculating the performance of dish-type solar thermal collectors and power systems

NASA Technical Reports Server (NTRS)

Jaffe, L. D.

1984-01-01

The CONC/11 computer program designed for calculating the performance of dish-type solar thermal collectors and power systems is discussed. This program is intended to aid the system or collector designer in evaluating the performance to be expected with possible design alternatives. From design or test data on the characteristics of the various subsystems, CONC/11 calculates the efficiencies of the collector and the overall power system as functions of the receiver temperature for a specified insolation. If desired, CONC/11 will also determine the receiver aperture and the receiver temperature that will provide the highest efficiencies at a given insolation. The program handles both simple and compound concentrators. The CONC/11 is written in Athena Extended FORTRAN (similar to FORTRAN 77) to operate primarily in an interactive mode on a Sperry 1100/81 computer. It could also be used on many small computers. A user's manual is also provided for this program.

Operational procedures for ground station operation: ATS-3 Hawaii-Ames satellite link experiment

NASA Technical Reports Server (NTRS)

Nishioka, K.; Gross, E. H.

1979-01-01

Hardware description and operational procedures for the ATS-3 Hawaii-Ames satellite computer link are presented in basic step-by-step instructions. Transmit and receive channels and frequencies are given. Details such as switch settings for activating the station to the sequence of turning switches on are provided. Methods and procedures for troubleshooting common problems encountered with communication stations are also provided.

A simulation exercise of a cavity-type solar receiver using the HEAP program

NASA Technical Reports Server (NTRS)

Lansing, F. L.

1979-01-01

A computer program has been developed at JPL to support the advanced studies of solar receivers in high concentration solar-thermal-electric power plants. This work presents briefly the program methodology, input data required, expected output results, capabilities and limitations. The program was used to simulate an existing 5 kwt experimental receiver of a cavity type. The receiver is located at the focus of a paraboloid dish and is connected to a Stirling engine. Both steady state and transient performance simulation were given. Details about the receiver modeling were also presented to illustrate the procedure followed. Simulated temperature patterns were found in good agreement with test data obtained by high temperature thermocouples. The simulated receiver performance was extrapolated to various operating conditions not attained experimentally. The results of the parameterization study were fitted to a general performance expression to determine the receiver characteristic constraints. The latter were used to optimize the receiver operating conditions to obtain the highest overall conversion efficiency.

Endpoint-based parallel data processing in a parallel active messaging interface of a parallel computer

DOEpatents

Archer, Charles J; Blocksome, Michael E; Ratterman, Joseph D; Smith, Brian E

2014-02-11

Endpoint-based parallel data processing in a parallel active messaging interface ('PAMI') of a parallel computer, the PAMI composed of data communications endpoints, each endpoint including a specification of data communications parameters for a thread of execution on a compute node, including specifications of a client, a context, and a task, the compute nodes coupled for data communications through the PAMI, including establishing a data communications geometry, the geometry specifying, for tasks representing processes of execution of the parallel application, a set of endpoints that are used in collective operations of the PAMI including a plurality of endpoints for one of the tasks; receiving in endpoints of the geometry an instruction for a collective operation; and executing the instruction for a collective opeartion through the endpoints in dependence upon the geometry, including dividing data communications operations among the plurality of endpoints for one of the tasks.

Dispatching packets on a global combining network of a parallel computer

DOEpatents

Almasi, Gheorghe [Ardsley, NY; Archer, Charles J [Rochester, MN

2011-07-19

Methods, apparatus, and products are disclosed for dispatching packets on a global combining network of a parallel computer comprising a plurality of nodes connected for data communications using the network capable of performing collective operations and point to point operations that include: receiving, by an origin system messaging module on an origin node from an origin application messaging module on the origin node, a storage identifier and an operation identifier, the storage identifier specifying storage containing an application message for transmission to a target node, and the operation identifier specifying a message passing operation; packetizing, by the origin system messaging module, the application message into network packets for transmission to the target node, each network packet specifying the operation identifier and an operation type for the message passing operation specified by the operation identifier; and transmitting, by the origin system messaging module, the network packets to the target node.

Correctness of multi-detector-row computed tomography for diagnosing mechanical prosthetic heart valve disorders using operative findings as a gold standard.

PubMed

Tsai, I-Chen; Lin, Yung-Kai; Chang, Yen; Fu, Yun-Ching; Wang, Chung-Chi; Hsieh, Shih-Rong; Wei, Hao-Ji; Tsai, Hung-Wen; Jan, Sheng-Ling; Wang, Kuo-Yang; Chen, Min-Chi; Chen, Clayton Chi-Chang

2009-04-01

The purpose was to compare the findings of multi-detector computed tomography (MDCT) in prosthetic valve disorders using the operative findings as a gold standard. In a 3-year period, we prospectively enrolled 25 patients with 31 prosthetic heart valves. MDCT and transthoracic echocardiography (TTE) were done to evaluate pannus formation, prosthetic valve dysfunction, suture loosening (paravalvular leak) and pseudoaneurysm formation. Patients indicated for surgery received an operation within 1 week. The MDCT findings were compared with the operative findings. One patient with a Björk-Shiley valve could not be evaluated by MDCT due to a severe beam-hardening artifact; thus, the exclusion rate for MDCT was 3.2% (1/31). Prosthetic valve disorders were suspected in 12 patients by either MDCT or TTE. Six patients received an operation that included three redo aortic valve replacements, two redo mitral replacements and one Amplatzer ductal occluder occlusion of a mitral paravalvular leak. The concordance of MDCT for diagnosing and localizing prosthetic valve disorders and the surgical findings was 100%. Except for images impaired by severe beam-hardening artifacts, MDCT provides excellent delineation of prosthetic valve disorders.

Self-pacing direct memory access data transfer operations for compute nodes in a parallel computer

DOEpatents

Blocksome, Michael A

2015-02-17

Methods, apparatus, and products are disclosed for self-pacing DMA data transfer operations for nodes in a parallel computer that include: transferring, by an origin DMA on an origin node, a RTS message to a target node, the RTS message specifying an message on the origin node for transfer to the target node; receiving, in an origin injection FIFO for the origin DMA from a target DMA on the target node in response to transferring the RTS message, a target RGET descriptor followed by a DMA transfer operation descriptor, the DMA descriptor for transmitting a message portion to the target node, the target RGET descriptor specifying an origin RGET descriptor on the origin node that specifies an additional DMA descriptor for transmitting an additional message portion to the target node; processing, by the origin DMA, the target RGET descriptor; and processing, by the origin DMA, the DMA transfer operation descriptor.

Reconfigurable environmentally adaptive computing

NASA Technical Reports Server (NTRS)

Coxe, Robin L. (Inventor); Galica, Gary E. (Inventor)

2008-01-01

Described are methods and apparatus, including computer program products, for reconfigurable environmentally adaptive computing technology. An environmental signal representative of an external environmental condition is received. A processing configuration is automatically selected, based on the environmental signal, from a plurality of processing configurations. A reconfigurable processing element is reconfigured to operate according to the selected processing configuration. In some examples, the environmental condition is detected and the environmental signal is generated based on the detected condition.

Evaluation of electrosurgical interference to low-power spread-spectrum local area net transceivers.

PubMed

Gibby, G L; Schwab, W K; Miller, W C

1997-11-01

To study whether an electrosurgery device interferes with the operation of a low-power spread-spectrum wireless network adapter. Nonrandomized, unblinded trials with controls, conducted in the corridor of our institution's operating suite using two portable computers equipped with RoamAbout omnidirectional 250 mW spread-spectrum 928 MHz wireless network adapters. To simulate high power electrosurgery interference, a 100-watt continuous electrocoagulation arc was maintained five feet from the receiving adapter, while device reported signal to noise values were measured at 150 feet and 400 feet distance between the wireless-networked computers. At 150 feet range, and with continuous 100-watt electrocoagulation arc five feet from one computer, error-corrected local area net throughput was measured by sending and receiving a large file multiple times. The reported signal to noise (N = 50) decreased with electrocoagulation from 36.42+/-3.47 (control) to 31.85+/-3.64 (electrocoagulation) (p < 0.001) at 400 feet inter-adapter distance, and from 64.53+/-1.43 (control) to 60.12+/-3.77 (electrocoagulation) (p < 0.001) at 150 feet inter-adapter distance. There was no statistically significant change in network throughput (average 93 kbyte/second) at 150 feet inter-adapter distance, either transmitting or receiving during continuous 100 Watt electrocoagulation arc. The manufacturer indicates "acceptable" performance will be obtained with signal to noise values as low as 20. In view of this, while electrocoagulation affects this spread spectrum network adapter, the effects are small even at 400 feet. At a distance of 150 feet, no discernible effect on network communications was found, suggesting that if other obstructions are minimal, within a wide range on one floor of an operating suite, network communications may be maintained using the technology of this wireless spread spectrum network adapter. The impact of such adapters on cardiac pacemakers should be studied. Wireless spread spectrum network adapters are an attractive technology for mobile computer communications in the operating room.

Profiling an application for power consumption during execution on a plurality of compute nodes

DOEpatents

Archer, Charles J.; Blocksome, Michael A.; Peters, Amanda E.; Ratterman, Joseph D.; Smith, Brian E.

2012-08-21

Methods, apparatus, and products are disclosed for profiling an application for power consumption during execution on a compute node that include: receiving an application for execution on a compute node; identifying a hardware power consumption profile for the compute node, the hardware power consumption profile specifying power consumption for compute node hardware during performance of various processing operations; determining a power consumption profile for the application in dependence upon the application and the hardware power consumption profile for the compute node; and reporting the power consumption profile for the application.

Computer-assisted versus non-computer-assisted preoperative planning of corrective osteotomy for extra-articular distal radius malunions: a randomized controlled trial.

PubMed

Leong, Natalie L; Buijze, Geert A; Fu, Eric C; Stockmans, Filip; Jupiter, Jesse B

2010-12-14

Malunion is the most common complication of distal radius fracture. It has previously been demonstrated that there is a correlation between the quality of anatomical correction and overall wrist function. However, surgical correction can be difficult because of the often complex anatomy associated with this condition. Computer assisted surgical planning, combined with patient-specific surgical guides, has the potential to improve pre-operative understanding of patient anatomy as well as intra-operative accuracy. For patients with malunion of the distal radius fracture, this technology could significantly improve clinical outcomes that largely depend on the quality of restoration of normal anatomy. Therefore, the objective of this study is to compare patient outcomes after corrective osteotomy for distal radius malunion with and without preoperative computer-assisted planning and peri-operative patient-specific surgical guides. This study is a multi-center randomized controlled trial of conventional planning versus computer-assisted planning for surgical correction of distal radius malunion. Adult patients with extra-articular malunion of the distal radius will be invited to enroll in our study. After providing informed consent, subjects will be randomized to two groups: one group will receive corrective surgery with conventional preoperative planning, while the other will receive corrective surgery with computer-assisted pre-operative planning and peri-operative patient specific surgical guides. In the computer-assisted planning group, a CT scan of the affected forearm as well as the normal, contralateral forearm will be obtained. The images will be used to construct a 3D anatomical model of the defect and patient-specific surgical guides will be manufactured. Outcome will be measured by DASH and PRWE scores, grip strength, radiographic measurements, and patient satisfaction at 3, 6, and 12 months postoperatively. Computer-assisted surgical planning, combined with patient-specific surgical guides, is a powerful new technology that has the potential to improve the accuracy and consistency of orthopaedic surgery. To date, the role of this technology in upper extremity surgery has not been adequately investigated, and it is unclear whether its use provides any significant clinical benefit over traditional preoperative imaging protocols. Our study will represent the first randomized controlled trial investigating the use of computer assisted surgery in corrective osteotomy for distal radius malunions. NCT01193010.

Improving the Capture and Re-Use of Data with Wearable Computers

NASA Technical Reports Server (NTRS)

Pfarr, Barbara; Fating, Curtis C.; Green, Daniel; Powers, Edward I. (Technical Monitor)

2001-01-01

At the Goddard Space Flight Center, members of the Real-Time Software Engineering Branch are developing a wearable, wireless, voice-activated computer for use in a wide range of crosscutting space applications that would benefit from having instant Internet, network, and computer access with complete mobility and hands-free operations. These applications can be applied across many fields and disciplines including spacecraft fabrication, integration and testing (including environmental testing), and astronaut on-orbit control and monitoring of experiments with ground based experimenters. To satisfy the needs of NASA customers, this wearable computer needs to be connected to a wireless network, to transmit and receive real-time video over the network, and to receive updated documents via the Internet or NASA servers. The voice-activated computer, with a unique vocabulary, will allow the users to access documentation in a hands free environment and interact in real-time with remote users. We will discuss wearable computer development, hardware and software issues, wireless network limitations, video/audio solutions and difficulties in language development.

Quantum Attack-Resistent Certificateless Multi-Receiver Signcryption Scheme

PubMed Central

Li, Huixian; Chen, Xubao; Pang, Liaojun; Shi, Weisong

2013-01-01

The existing certificateless signcryption schemes were designed mainly based on the traditional public key cryptography, in which the security relies on the hard problems, such as factor decomposition and discrete logarithm. However, these problems will be easily solved by the quantum computing. So the existing certificateless signcryption schemes are vulnerable to the quantum attack. Multivariate public key cryptography (MPKC), which can resist the quantum attack, is one of the alternative solutions to guarantee the security of communications in the post-quantum age. Motivated by these concerns, we proposed a new construction of the certificateless multi-receiver signcryption scheme (CLMSC) based on MPKC. The new scheme inherits the security of MPKC, which can withstand the quantum attack. Multivariate quadratic polynomial operations, which have lower computation complexity than bilinear pairing operations, are employed in signcrypting a message for a certain number of receivers in our scheme. Security analysis shows that our scheme is a secure MPKC-based scheme. We proved its security under the hardness of the Multivariate Quadratic (MQ) problem and its unforgeability under the Isomorphism of Polynomials (IP) assumption in the random oracle model. The analysis results show that our scheme also has the security properties of non-repudiation, perfect forward secrecy, perfect backward secrecy and public verifiability. Compared with the existing schemes in terms of computation complexity and ciphertext length, our scheme is more efficient, which makes it suitable for terminals with low computation capacity like smart cards. PMID:23967037

The effects of a computer skill training programme adopting social comparison and self-efficacy enhancement strategies on self-concept and skill outcome in trainees with physical disabilities.

PubMed

Tam, S F

2000-10-15

The aim of this controlled, quasi-experimental study was to evaluate the effects of both self-efficacy enhancement and social comparison training strategy on computer skills learning and self-concept outcome of trainees with physical disabilities. The self-efficacy enhancement group comprised 16 trainees, the tutorial training group comprised 15 trainees, and there were 25 subjects in the control group. Both the self-efficacy enhancement group and the tutorial training group received a 15 week computer skills training course, including generic Chinese computer operation, Chinese word processing and Chinese desktop publishing skills. The self-efficacy enhancement group received training with tutorial instructions that incorporated self-efficacy enhancement strategies and experienced self-enhancing social comparisons. The tutorial training group received behavioural learning-based tutorials only, and the control group did not receive any training. The following measurements were employed to evaluate the outcomes: the Self-Concept Questionnaire for the Physically Disabled Hong Kong Chinese (SCQPD), the computer self-efficacy rating scale and the computer performance rating scale. The self-efficacy enhancement group showed significantly better computer skills learning outcome, total self-concept, and social self-concept than the tutorial training group. The self-efficacy enhancement group did not show significant changes in their computer self-efficacy: however, the tutorial training group showed a significant lowering of their computer self-efficacy. The training strategy that incorporated self-efficacy enhancement and positive social comparison experiences maintained the computer self-efficacy of trainees with physical disabilities. This strategy was more effective in improving the learning outcome (p = 0.01) and self-concept (p = 0.05) of the trainees than the conventional tutorial-based training strategy.

The Feasibility of Classifying Breast Masses Using a Computer-Assisted Diagnosis (CAD) System Based on Ultrasound Elastography and BI-RADS Lexicon.

PubMed

Fleury, Eduardo F C; Gianini, Ana Claudia; Marcomini, Karem; Oliveira, Vilmar

2018-01-01

To determine the applicability of a computer-aided diagnostic system strain elastography system for the classification of breast masses diagnosed by ultrasound and scored using the criteria proposed by the breast imaging and reporting data system ultrasound lexicon and to determine the diagnostic accuracy and interobserver variability. This prospective study was conducted between March 1, 2016, and May 30, 2016. A total of 83 breast masses subjected to percutaneous biopsy were included. Ultrasound elastography images before biopsy were interpreted by 3 radiologists with and without the aid of computer-aided diagnostic system for strain elastography. The parameters evaluated by each radiologist results were sensitivity, specificity, and diagnostic accuracy, with and without computer-aided diagnostic system for strain elastography. Interobserver variability was assessed using a weighted κ test and an intraclass correlation coefficient. The areas under the receiver operating characteristic curves were also calculated. The areas under the receiver operating characteristic curve were 0.835, 0.801, and 0.765 for readers 1, 2, and 3, respectively, without computer-aided diagnostic system for strain elastography, and 0.900, 0.926, and 0.868, respectively, with computer-aided diagnostic system for strain elastography. The intraclass correlation coefficient between the 3 readers was 0.6713 without computer-aided diagnostic system for strain elastography and 0.811 with computer-aided diagnostic system for strain elastography. The proposed computer-aided diagnostic system for strain elastography system has the potential to improve the diagnostic performance of radiologists in breast examination using ultrasound associated with elastography.

Ultra-low power high precision magnetotelluric receiver array based customized computer and wireless sensor network

NASA Astrophysics Data System (ADS)

Chen, R.; Xi, X.; Zhao, X.; He, L.; Yao, H.; Shen, R.

2016-12-01

Dense 3D magnetotelluric (MT) data acquisition owns the benefit of suppressing the static shift and topography effect, can achieve high precision and high resolution inversion for underground structure. This method may play an important role in mineral exploration, geothermal resources exploration, and hydrocarbon exploration. It's necessary to reduce the power consumption greatly of a MT signal receiver for large-scale 3D MT data acquisition while using sensor network to monitor data quality of deployed MT receivers. We adopted a series of technologies to realized above goal. At first, we designed an low-power embedded computer which can couple with other parts of MT receiver tightly and support wireless sensor network. The power consumption of our embedded computer is less than 1 watt. Then we designed 4-channel data acquisition subsystem which supports 24-bit analog-digital conversion, GPS synchronization, and real-time digital signal processing. Furthermore, we developed the power supply and power management subsystem for MT receiver. At last, a series of software, which support data acquisition, calibration, wireless sensor network, and testing, were developed. The software which runs on personal computer can monitor and control over 100 MT receivers on the field for data acquisition and quality control. The total power consumption of the receiver is about 2 watts at full operation. The standby power consumption is less than 0.1 watt. Our testing showed that the MT receiver can acquire good quality data at ground with electrical dipole length as 3 m. Over 100 MT receivers were made and used for large-scale geothermal exploration in China with great success.

Toward a Theory of Sequencing: Study 3-2: An Exploration of Transitivities Formulated From a Set of Piagetian-Derived Operations and Their Implications in Traversing Learning Hierarchies.

ERIC Educational Resources Information Center

Hopkins, Layne Victor

Certain transitivity relationships formulated from reversible operations were examined. Thirty randomly selected fifth grade students received instructional episodes, developed for each identified behavioral objective and its inverse (on unspecified content), presented via the IBM 1500 Instructional Computer System. It was found that students who…

Manhunting: Counter-Network Organization for Irregular Warfare

DTIC Science & Technology

2009-09-01

received his B.A. in International Relations from the University of Kansas in 1985 and M.S. in Computer Applications Management from Lesley University...collection management , and targeting.b. Operational level processes begin with intelligence on the adversary capabilities with granular focus to mitigate... managers work with analysts, targeting experts, decision makers, planners, and operations personnel, guiding multidisciplinary intelligence collection to

A spruce budworm sampling program for HUSKY HUNTER field data recorders.

Treesearch

Fred H. Schmidt

1992-01-01

A program for receiving sampling data for all immature stages of the western spruce budworm (Choristoneura occidentals Freeman) is described. Versions were designed to be used on field data recorders with either CP/M or DOS operating systems, such as the HUSKY HUNTER (Models 1, 2, and 16), but they also may be used on personal computers with compatible operating...

A handheld computer as part of a portable in vivo knee joint load monitoring system

PubMed Central

Szivek, JA; Nandakumar, VS; Geffre, CP; Townsend, CP

2009-01-01

In vivo measurement of loads and pressures acting on articular cartilage in the knee joint during various activities and rehabilitative therapies following focal defect repair will provide a means of designing activities that encourage faster and more complete healing of focal defects. It was the goal of this study to develop a totally portable monitoring system that could be used during various activities and allow continuous monitoring of forces acting on the knee. In order to make the monitoring system portable, a handheld computer with custom software, a USB powered miniature wireless receiver and a battery-powered coil were developed to replace a currently used computer, AC powered bench top receiver and power supply. A Dell handheld running Windows Mobile operating system(OS) programmed using Labview was used to collect strain measurements. Measurements collected by the handheld based system connected to the miniature wireless receiver were compared with the measurements collected by a hardwired system and a computer based system during bench top testing and in vivo testing. The newly developed handheld based system had a maximum accuracy of 99% when compared to the computer based system. PMID:19789715

Optimized collectives using a DMA on a parallel computer

DOEpatents

Chen, Dong [Croton On Hudson, NY; Gabor, Dozsa [Ardsley, NY; Giampapa, Mark E [Irvington, NY; Heidelberger,; Phillip, [Cortlandt Manor, NY

2011-02-08

Optimizing collective operations using direct memory access controller on a parallel computer, in one aspect, may comprise establishing a byte counter associated with a direct memory access controller for each submessage in a message. The byte counter includes at least a base address of memory and a byte count associated with a submessage. A byte counter associated with a submessage is monitored to determine whether at least a block of data of the submessage has been received. The block of data has a predetermined size, for example, a number of bytes. The block is processed when the block has been fully received, for example, when the byte count indicates all bytes of the block have been received. The monitoring and processing may continue for all blocks in all submessages in the message.

Telemetry Data Collection from Oscar Satellite

NASA Technical Reports Server (NTRS)

Haddock, Paul C.; Horan, Stephen

1998-01-01

This paper discusses the design, configuration, and operation of a satellite station built for the Center for Space Telemetering and Telecommunications Laboratory in the Klipsch School of Electrical and Computer Engineering Engineering at New Mexico State University (NMSU). This satellite station consists of a computer-controlled antenna tracking system, 2m/70cm transceiver, satellite tracking software, and a demodulator. The satellite station receives satellite,telemetry, allows for voice communications, and will be used in future classes. Currently this satellite station is receiving telemetry from an amateur radio satellite, UoSAT-OSCAR-11. Amateur radio satellites are referred to as Orbiting Satellites Carrying Amateur Radio (OSCAR) satellites as discussed in the next section.

Scanning computed confocal imager

DOEpatents

George, John S.

2000-03-14

There is provided a confocal imager comprising a light source emitting a light, with a light modulator in optical communication with the light source for varying the spatial and temporal pattern of the light. A beam splitter receives the scanned light and direct the scanned light onto a target and pass light reflected from the target to a video capturing device for receiving the reflected light and transferring a digital image of the reflected light to a computer for creating a virtual aperture and outputting the digital image. In a transmissive mode of operation the invention omits the beam splitter means and captures light passed through the target.

RFI Math Model programs for predicting intermodulation interference

NASA Technical Reports Server (NTRS)

Stafford, J. M.

1974-01-01

Receivers operating on a space vehicle or an aircraft having many on-board transmitters are subject to intermodulation interference from mixing in the transmitting antenna systems, the external environment, or the receiver front-ends. This paper presents the techniques utilized in RFI Math Model computer programs that were developed to aid in the prevention of interference by predicting problem areas prior to occurrence. Frequencies and amplitudes of possible intermodulation products generated in the external environment are calculated and compared to receiver sensitivities. Intermodulation products generated in receivers are evaluated to determine the adequacy of preselector ejection.

Autonomous Integrated Receive System (AIRS) requirements definition. Volume 2: Design and development

NASA Technical Reports Server (NTRS)

Chie, C. M.; White, M. A.; Lindsey, W. C.; Davarian, F.; Dixon, R. C.

1984-01-01

Functional requirements and specifications are defined for an autonomous integrated receive system (AIRS) to be used as an improvement in the current tracking and data relay satellite system (TDRSS), and as a receiving system in the future tracking and data acquisition system (TDAS). The AIRS provides improved acquisition, tracking, bit error rate (BER), RFI mitigation techniques, and data operations performance compared to the current TDRSS ground segment receive system. A computer model of the AIRS is used to provide simulation results predicting the performance of AIRS. Cost and technology assessments are included.

The DoD's High Performance Computing Modernization Program - Ensuing the National Earth Systems Prediction Capability Becomes Operational

NASA Astrophysics Data System (ADS)

Burnett, W.

2016-12-01

The Department of Defense's (DoD) High Performance Computing Modernization Program (HPCMP) provides high performance computing to address the most significant challenges in computational resources, software application support and nationwide research and engineering networks. Today, the HPCMP has a critical role in ensuring the National Earth System Prediction Capability (N-ESPC) achieves initial operational status in 2019. A 2015 study commissioned by the HPCMP found that N-ESPC computational requirements will exceed interconnect bandwidth capacity due to the additional load from data assimilation and passing connecting data between ensemble codes. Memory bandwidth and I/O bandwidth will continue to be significant bottlenecks for the Navy's Hybrid Coordinate Ocean Model (HYCOM) scalability - by far the major driver of computing resource requirements in the N-ESPC. The study also found that few of the N-ESPC model developers have detailed plans to ensure their respective codes scale through 2024. Three HPCMP initiatives are designed to directly address and support these issues: Productivity Enhancement, Technology, Transfer and Training (PETTT), the HPCMP Applications Software Initiative (HASI), and Frontier Projects. PETTT supports code conversion by providing assistance, expertise and training in scalable and high-end computing architectures. HASI addresses the continuing need for modern application software that executes effectively and efficiently on next-generation high-performance computers. Frontier Projects enable research and development that could not be achieved using typical HPCMP resources by providing multi-disciplinary teams access to exceptional amounts of high performance computing resources. Finally, the Navy's DoD Supercomputing Resource Center (DSRC) currently operates a 6 Petabyte system, of which Naval Oceanography receives 15% of operational computational system use, or approximately 1 Petabyte of the processing capability. The DSRC will provide the DoD with future computing assets to initially operate the N-ESPC in 2019. This talk will further describe how DoD's HPCMP will ensure N-ESPC becomes operational, efficiently and effectively, using next-generation high performance computing.

Buffer thermal energy storage for an air Brayton solar engine

NASA Technical Reports Server (NTRS)

Strumpf, H. J.; Barr, K. P.

1981-01-01

The application of latent-heat buffer thermal energy storage to a point-focusing solar receiver equipped with an air Brayton engine was studied. To demonstrate the effect of buffer thermal energy storage on engine operation, a computer program was written which models the recuperator, receiver, and thermal storage device as finite-element thermal masses. Actual operating or predicted performance data are used for all components, including the rotating equipment. Based on insolation input and a specified control scheme, the program predicts the Brayton engine operation, including flows, temperatures, and pressures for the various components, along with the engine output power. An economic parametric study indicates that the economic viability of buffer thermal energy storage is largely a function of the achievable engine life.

Assigning unique identification numbers to new user accounts and groups in a computing environment with multiple registries

DOEpatents

DeRobertis, Christopher V.; Lu, Yantian T.

2010-02-23

A method, system, and program storage device for creating a new user account or user group with a unique identification number in a computing environment having multiple user registries is provided. In response to receiving a command to create a new user account or user group, an operating system of a clustered computing environment automatically checks multiple registries configured for the operating system to determine whether a candidate identification number for the new user account or user group has been assigned already to one or more existing user accounts or groups, respectively. The operating system automatically assigns the candidate identification number to the new user account or user group created in a target user registry if the checking indicates that the candidate identification number has not been assigned already to any of the existing user accounts or user groups, respectively.

Data processing techniques used with MST radars: A review

NASA Technical Reports Server (NTRS)

Rastogi, P. K.

1983-01-01

The data processing methods used in high power radar probing of the middle atmosphere are examined. The radar acts as a spatial filter on the small scale refractivity fluctuations in the medium. The characteristics of the received signals are related to the statistical properties of these fluctuations. A functional outline of the components of a radar system is given. Most computation intensive tasks are carried out by the processor. The processor computes a statistical function of the received signals, simultaneously for a large number of ranges. The slow fading of atmospheric signals is used to reduce the data input rate to the processor by coherent integration. The inherent range resolution of the radar experiments can be improved significant with the use of pseudonoise phase codes to modulate the transmitted pulses and a corresponding decoding operation on the received signals. Commutability of the decoding and coherent integration operations is used to obtain a significant reduction in computations. The limitations of the processors are outlined. At the next level of data reduction, the measured function is parameterized by a few spectral moments that can be related to physical processes in the medium. The problems encountered in estimating the spectral moments in the presence of strong ground clutter, external interference, and noise are discussed. The graphical and statistical analysis of the inferred parameters are outlined. The requirements for special purpose processors for MST radars are discussed.

The 1980 summer research fellowship program

NASA Technical Reports Server (NTRS)

Darden, G. C. (Compiler)

1980-01-01

The problem of incorporating visual input into robot systems is described. The photochemistry of the stratosphere, particularly possible permutations of the ozone layer, is discussed. Photoelectrochemical properties of metal thio-hypodiphosphates are investigated. Extreme eigenvalues are computed by the Lancqos approach. The rotational Raman spectra of the molecular atmosphere is studied. A computer operated mathematical symbolic manipulation system is described. Preparation of polycrystalline semiconductor electrodes of tungsten and molybdenum dichalcogenides is received.

Study of mathematical modeling of communication systems transponders and receivers

NASA Technical Reports Server (NTRS)

Walsh, J. R.

1972-01-01

The modeling of communication receivers is described at both the circuit detail level and at the block level. The largest effort was devoted to developing new models at the block modeling level. The available effort did not permit full development of all of the block modeling concepts envisioned, but idealized blocks were developed for signal sources, a variety of filters, limiters, amplifiers, mixers, and demodulators. These blocks were organized into an operational computer simulation of communications receiver circuits identified as the frequency and time circuit analysis technique (FATCAT). The simulation operates in both the time and frequency domains, and permits output plots or listings of either frequency spectra or time waveforms from any model block. Transfer between domains is handled with a fast Fourier transform algorithm.

The instrumental principles of MST radars and incoherent scatter radars and the configuration of radar system hardware

NASA Technical Reports Server (NTRS)

Roettger, Juergen

1989-01-01

The principle of pulse modulation used in the case of coherent scatter radars (MST radars) is discussed. Coherent detection and the corresponding system configuration is delineated. Antenna requirements and design are outlined and the phase-coherent transmitter/receiver system is described. Transmit/receive duplexers, transmitters, receivers, and quadrature detectors are explained. The radar controller, integrator, decoder and correlator design as well as the data transfer and the control and monitoring by the host computer are delineated. Typical operation parameters of some well-known radars are summarized.

The Basilar Artery on Computed Tomography Angiography Prognostic Score for Basilar Artery Occlusion.

PubMed

Alemseged, Fana; Shah, Darshan G; Diomedi, Marina; Sallustio, Fabrizio; Bivard, Andrew; Sharma, Gagan; Mitchell, Peter J; Dowling, Richard J; Bush, Steven; Yan, Bernard; Caltagirone, Carlo; Floris, Roberto; Parsons, Mark W; Levi, Christopher R; Davis, Stephen M; Campbell, Bruce C V

2017-03-01

Basilar artery occlusion is associated with high risk of disability and mortality. This study aimed to assess the prognostic value of a new radiological score: the Basilar Artery on Computed Tomography Angiography (BATMAN) score. A retrospective analysis of consecutive stroke patients with basilar artery occlusion diagnosed on computed tomographic angiography was performed. BATMAN score is a 10-point computed tomographic angiography-based grading system which incorporates thrombus burden and the presence of collaterals. Reliability was assessed with intraclass coefficient correlation. Good outcome was defined as modified Rankin Scale score of ≤3 at 3 months and successful reperfusion as thrombolysis in cerebral infarction 2b-3. BATMAN score was externally validated and compared with the Posterior Circulation Collateral score. The derivation cohort included 83 patients with 41 in the validation cohort. In receiver operating characteristic (ROC) analysis, BATMAN score had an area under receiver operating characteristic curve of 0.81 (95% confidence interval [CI], 0.7-0.9) in derivation cohort and an area under receiver operating characteristic curve of 0.74 (95% CI, 0.6-0.9) in validation cohort. In logistic regression adjusted for age and clinical severity, BATMAN score of <7 was associated with poor outcome in derivation cohort (odds ratio, 5.5; 95% CI, 1.4-21; P =0.01), in validation cohort (odds ratio, 6.9; 95% CI, 1.4-33; P =0.01), and in endovascular patients, after adjustment for recanalization and time to treatment (odds ratio, 4.8; 95% CI, 1.2-18; P =0.01). BATMAN score of <7 was not associated with recanalization. Interrater agreement was substantial (intraclass coefficient correlation, 0.85; 95% CI, 0.8-0.9). BATMAN score had greater accuracy compared with Posterior Circulation Collateral score ( P =0.04). The addition of collateral quality to clot burden in BATMAN score seems to improve prognostic accuracy in basilar artery occlusion patients. © 2017 American Heart Association, Inc.

Ny-Alesund Geodetic Observatory

NASA Technical Reports Server (NTRS)

Sieber, Moritz

2013-01-01

In 2012 the 20-m telescope at Ny-Alesund, Svalbard, operated by the Norwegian Mapping Authority (NMA), took part in 163 out of 168 scheduled sessions of the IVS program. Since spring, all data was transferred by network, and the receiver monitoring computer was replaced by a bus-coupler. In autumn, the NMA received building permission for a new observatory from the Governor of Svalbard. The bidding process and first construction work for the infrastructure will start in 2013.

Validating an operational physical method to compute surface radiation from geostationary satellites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sengupta, Manajit; Dhere, Neelkanth G.; Wohlgemuth, John H.

We developed models to compute global horizontal irradiance (GHI) and direct normal irradiance (DNI) over the last three decades. These models can be classified as empirical or physical based on the approach. Empirical models relate ground-based observations with satellite measurements and use these relations to compute surface radiation. Physical models consider the physics behind the radiation received at the satellite and create retrievals to estimate surface radiation. Furthermore, while empirical methods have been traditionally used for computing surface radiation for the solar energy industry, the advent of faster computing has made operational physical models viable. The Global Solar Insolation Projectmore » (GSIP) is a physical model that computes DNI and GHI using the visible and infrared channel measurements from a weather satellite. GSIP uses a two-stage scheme that first retrieves cloud properties and uses those properties in a radiative transfer model to calculate GHI and DNI. Developed for polar orbiting satellites, GSIP has been adapted to NOAA's Geostationary Operation Environmental Satellite series and can run operationally at high spatial resolutions. Our method holds the possibility of creating high quality datasets of GHI and DNI for use by the solar energy industry. We present an outline of the methodology and results from running the model as well as a validation study using ground-based instruments.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kring, C.T.; Varma, V.K.; Jatko, W.B.

The US Army and Team Crusader (United Defense, Lockheed Martin Armament Systems, etc.) are developing the next generation howitzer, the Crusader. The development program includes an advanced, self-propelled liquid propellant howitzer and a companion resupply vehicle. The resupply vehicle is intended to rendezvous with the howitzer near the battlefront and replenish ammunition, fuel, and other material. The Army has recommended that Crusader incorporate new and innovative technologies to improve performance and safety. One conceptual design proposes a robotic resupply boom on the resupply vehicle to upload supplies to the howitzer. The resupply boom would normally be retracted inside the resupplymore » vehicle during transit. When the two vehicles are within range of the resupply boom, the boom would be extended to a receiving port on the howitzer. In order to reduce exposure to small arms fire or nuclear, biological, and chemical hazards, the crew would remain inside the resupply vehicle during the resupply operation. The process of extending the boom and linking with the receiving port is called docking. A boom operator would be designated to maneuver the boom into contact with the receiving port using a mechanical joystick. The docking operation depends greatly upon the skill of the boom operator to manipulate the boom into docking position. Computer simulations at the National Aeronautics and Space Administration have shown that computer-assisted or autonomous docking can improve the ability of the operator to dock safely and quickly. This document describes the present status of the Crusader Autonomous Docking System (CADS) implemented at Oak Ridge National laboratory (ORNL). The purpose of the CADS project is to determine the feasibility and performance limitations of vision systems to satisfy the autonomous docking requirements for Crusader and conduct a demonstration under controlled conditions.« less

Portable multiplicity counter

DOEpatents

Newell, Matthew R [Los Alamos, NM; Jones, David Carl [Los Alamos, NM

2009-09-01

A portable multiplicity counter has signal input circuitry, processing circuitry and a user/computer interface disposed in a housing. The processing circuitry, which can comprise a microcontroller integrated circuit operably coupled to shift register circuitry implemented in a field programmable gate array, is configured to be operable via the user/computer interface to count input signal pluses receivable at said signal input circuitry and record time correlations thereof in a total counting mode, coincidence counting mode and/or a multiplicity counting mode. The user/computer interface can be for example an LCD display/keypad and/or a USB interface. The counter can include a battery pack for powering the counter and low/high voltage power supplies for biasing external detectors so that the counter can be configured as a hand-held device for counting neutron events.

Prognostic Significance of Tumor Size of Small Lung Adenocarcinomas Evaluated with Mediastinal Window Settings on Computed Tomography

PubMed Central

Sakao, Yukinori; Kuroda, Hiroaki; Mun, Mingyon; Uehara, Hirofumi; Motoi, Noriko; Ishikawa, Yuichi; Nakagawa, Ken; Okumura, Sakae

2014-01-01

Background We aimed to clarify that the size of the lung adenocarcinoma evaluated using mediastinal window on computed tomography is an important and useful modality for predicting invasiveness, lymph node metastasis and prognosis in small adenocarcinoma. Methods We evaluated 176 patients with small lung adenocarcinomas (diameter, 1–3 cm) who underwent standard surgical resection. Tumours were examined using computed tomography with thin section conditions (1.25 mm thick on high-resolution computed tomography) with tumour dimensions evaluated under two settings: lung window and mediastinal window. We also determined the patient age, gender, preoperative nodal status, tumour size, tumour disappearance ratio, preoperative serum carcinoembryonic antigen levels and pathological status (lymphatic vessel, vascular vessel or pleural invasion). Recurrence-free survival was used for prognosis. Results Lung window, mediastinal window, tumour disappearance ratio and preoperative nodal status were significant predictive factors for recurrence-free survival in univariate analyses. Areas under the receiver operator curves for recurrence were 0.76, 0.73 and 0.65 for mediastinal window, tumour disappearance ratio and lung window, respectively. Lung window, mediastinal window, tumour disappearance ratio, preoperative serum carcinoembryonic antigen levels and preoperative nodal status were significant predictive factors for lymph node metastasis in univariate analyses; areas under the receiver operator curves were 0.61, 0.76, 0.72 and 0.66, for lung window, mediastinal window, tumour disappearance ratio and preoperative serum carcinoembryonic antigen levels, respectively. Lung window, mediastinal window, tumour disappearance ratio, preoperative serum carcinoembryonic antigen levels and preoperative nodal status were significant factors for lymphatic vessel, vascular vessel or pleural invasion in univariate analyses; areas under the receiver operator curves were 0.60, 0.81, 0.81 and 0.65 for lung window, mediastinal window, tumour disappearance ratio and preoperative serum carcinoembryonic antigen levels, respectively. Conclusions According to the univariate analyses including a logistic regression and ROCs performed for variables with p-values of <0.05 on univariate analyses, our results suggest that measuring tumour size using mediastinal window on high-resolution computed tomography is a simple and useful preoperative prognosis modality in small adenocarcinoma. PMID:25365326

Computational Evaluation of Latent Heat Energy Storage Using a High Temperature Phase Change Material

DTIC Science & Technology

2012-05-01

thermal energy storage system using molten silicon as a phase change material. A cylindrical receiver, absorber, converter system was evaluated using...temperature operation. This work computationally evaluates a thermal energy storage system using molten silicon as a phase change material. A cylindrical... salts ) offering a low power density and a low thermal conductivity, leading to a limited rate of charging and discharging (4). A focus on

Analyzing Dental Implant Sites From Cone Beam Computed Tomography Scans on a Tablet Computer: A Comparative Study Between iPad and 3 Display Systems.

PubMed

Carrasco, Alejandro; Jalali, Elnaz; Dhingra, Ajay; Lurie, Alan; Yadav, Sumit; Tadinada, Aditya

2017-06-01

The aim of this study was to compare a medical-grade PACS (picture archiving and communication system) monitor, a consumer-grade monitor, a laptop computer, and a tablet computer for linear measurements of height and width for specific implant sites in the posterior maxilla and mandible, along with visualization of the associated anatomical structures. Cone beam computed tomography (CBCT) scans were evaluated. The images were reviewed using PACS-LCD monitor, consumer-grade LCD monitor using CB-Works software, a 13″ MacBook Pro, and an iPad 4 using OsiriX DICOM reader software. The operators had to identify anatomical structures in each display using a 2-point scale. User experience between PACS and iPad was also evaluated by means of a questionnaire. The measurements were very similar for each device. P-values were all greater than 0.05, indicating no significant difference between the monitors for each measurement. The intraoperator reliability was very high. The user experience was similar in each category with the most significant difference regarding the portability where the PACS display received the lowest score and the iPad received the highest score. The iPad with retina display was comparable with the medical-grade monitor, producing similar measurements and image visualization, and thus providing an inexpensive, portable, and reliable screen to analyze CBCT images in the operating room during the implant surgery.

Evaluating the Psychometric Characteristics of Generated Multiple-Choice Test Items

ERIC Educational Resources Information Center

Gierl, Mark J.; Lai, Hollis; Pugh, Debra; Touchie, Claire; Boulais, André-Philippe; De Champlain, André

2016-01-01

Item development is a time- and resource-intensive process. Automatic item generation integrates cognitive modeling with computer technology to systematically generate test items. To date, however, items generated using cognitive modeling procedures have received limited use in operational testing situations. As a result, the psychometric…

Desarrollo de una Interfaz de Control para un Observatorio Astronómico Robotizado con fines educativos en la Facultad de Ciencias Exactas; Físicas y Naturales de la UNSJ

NASA Astrophysics Data System (ADS)

Pogrebinsky, L.; Francile, C.

We report the development and the construction of an Interface to Control a robotized Astronomical Observatory (ICOA), which allows to control the operation of an observatory based on a Meade LX200 telescope. The interface operates together with a computer to control and supervise all the local variables of the observatory, and can take the control of it in risky situations. It serves as a link among the control computer and all the necessary devices for the astronomical observation such as the telescope, the dome, the weather station, the CCD camera, the calibration devices and the security devices. The computer receives orders from an operator who can be or not at the site of observation. The goal of this robotized observatory is the operation in a secure, autonomous and unattended way, with the purpose of to be used remotely by the students of the "Facultad de Ciencias Exactas, Físicas y Naturales" of the UNSJ. FULL TEXT IN SPANISH

A Metric for Reducing False Positives in the Computer-Aided Detection of Breast Cancer from Dynamic Contrast-Enhanced Magnetic Resonance Imaging Based Screening Examinations of High-Risk Women.

PubMed

Levman, Jacob E D; Gallego-Ortiz, Cristina; Warner, Ellen; Causer, Petrina; Martel, Anne L

2016-02-01

Magnetic resonance imaging (MRI)-enabled cancer screening has been shown to be a highly sensitive method for the early detection of breast cancer. Computer-aided detection systems have the potential to improve the screening process by standardizing radiologists to a high level of diagnostic accuracy. This retrospective study was approved by the institutional review board of Sunnybrook Health Sciences Centre. This study compares the performance of a proposed method for computer-aided detection (based on the second-order spatial derivative of the relative signal intensity) with the signal enhancement ratio (SER) on MRI-based breast screening examinations. Comparison is performed using receiver operating characteristic (ROC) curve analysis as well as free-response receiver operating characteristic (FROC) curve analysis. A modified computer-aided detection system combining the proposed approach with the SER method is also presented. The proposed method provides improvements in the rates of false positive markings over the SER method in the detection of breast cancer (as assessed by FROC analysis). The modified computer-aided detection system that incorporates both the proposed method and the SER method yields ROC results equal to that produced by SER while simultaneously providing improvements over the SER method in terms of false positives per noncancerous exam. The proposed method for identifying malignancies outperforms the SER method in terms of false positives on a challenging dataset containing many small lesions and may play a useful role in breast cancer screening by MRI as part of a computer-aided detection system.

Have computers, will travel: providing on-site library instruction in rural health facilities using a portable computer lab.

PubMed

Neilson, Christine J

2010-01-01

The Saskatchewan Health Information Resources Partnership (SHIRP) provides library instruction to Saskatchewan's health care practitioners and students on placement in health care facilities as part of its mission to provide province-wide access to evidence-based health library resources. A portable computer lab was assembled in 2007 to provide hands-on training in rural health facilities that do not have computer labs of their own. Aside from some minor inconveniences, the introduction and operation of the portable lab has gone smoothly. The lab has been well received by SHIRP patrons and continues to be an essential part of SHIRP outreach.

Real-time operation without a real-time operating system for instrument control and data acquisition

NASA Astrophysics Data System (ADS)

Klein, Randolf; Poglitsch, Albrecht; Fumi, Fabio; Geis, Norbert; Hamidouche, Murad; Hoenle, Rainer; Looney, Leslie; Raab, Walfried; Viehhauser, Werner

2004-09-01

We are building the Field-Imaging Far-Infrared Line Spectrometer (FIFI LS) for the US-German airborne observatory SOFIA. The detector read-out system is driven by a clock signal at a certain frequency. This signal has to be provided and all other sub-systems have to work synchronously to this clock. The data generated by the instrument has to be received by a computer in a timely manner. Usually these requirements are met with a real-time operating system (RTOS). In this presentation we want to show how we meet these demands differently avoiding the stiffness of an RTOS. Digital I/O-cards with a large buffer separate the asynchronous working computers and the synchronous working instrument. The advantage is that the data processing computers do not need to process the data in real-time. It is sufficient that the computer can process the incoming data stream on average. But since the data is read-in synchronously, problems of relating commands and responses (data) have to be solved: The data is arriving at a fixed rate. The receiving I/O-card buffers the data in its buffer until the computer can access it. To relate the data to commands sent previously, the data is tagged by counters in the read-out electronics. These counters count the system's heartbeat and signals derived from that. The heartbeat and control signals synchronous with the heartbeat are sent by an I/O-card working as pattern generator. Its buffer gets continously programmed with a pattern which is clocked out on the control lines. A counter in the I/O-card keeps track of the amount of pattern words clocked out. By reading this counter, the computer knows the state of the instrument or knows the meaning of the data that will arrive with a certain time-tag.

What We Learn About Process Specification Languages from Studying Recipes

DTIC Science & Technology

1987-08-01

minutes or until very lightly browned. Add carrot, shallots, onion, celery root, mushrooms, and garlic ,· *I I* stir well *I add_to( chop ...a computer program. Most recipes require that each ingredient receives a preprocessing treatment (eg. peel, chop ) before being used. Thus, we found...named operations that must be performed by a cook such as chop , set_heat, ... (see section 7 for more details on these), "active operations

Definition and maintenance of a telemetry database dictionary

NASA Technical Reports Server (NTRS)

Knopf, William P. (Inventor)

2007-01-01

A telemetry dictionary database includes a component for receiving spreadsheet workbooks of telemetry data over a web-based interface from other computer devices. Another component routes the spreadsheet workbooks to a specified directory on the host processing device. A process then checks the received spreadsheet workbooks for errors, and if no errors are detected the spreadsheet workbooks are routed to another directory to await initiation of a remote database loading process. The loading process first converts the spreadsheet workbooks to comma separated value (CSV) files. Next, a network connection with the computer system that hosts the telemetry dictionary database is established and the CSV files are ported to the computer system that hosts the telemetry dictionary database. This is followed by a remote initiation of a database loading program. Upon completion of loading a flatfile generation program is manually initiated to generate a flatfile to be used in a mission operations environment by the core ground system.

Standard interface: Twin-coaxial converter

NASA Technical Reports Server (NTRS)

Lushbaugh, W. A.

1976-01-01

The network operations control center standard interface has been adopted as a standard computer interface for all future minicomputer based subsystem development for the Deep Space Network. Discussed is an intercomputer communications link using a pair of coaxial cables. This unit is capable of transmitting and receiving digital information at distances up to 600 m with complete ground isolation between the communicating devices. A converter is described that allows a computer equipped with the standard interface to use the twin coaxial link.

Organization of the secure distributed computing based on multi-agent system

NASA Astrophysics Data System (ADS)

Khovanskov, Sergey; Rumyantsev, Konstantin; Khovanskova, Vera

2018-04-01

Nowadays developing methods for distributed computing is received much attention. One of the methods of distributed computing is using of multi-agent systems. The organization of distributed computing based on the conventional network computers can experience security threats performed by computational processes. Authors have developed the unified agent algorithm of control system of computing network nodes operation. Network PCs is used as computing nodes. The proposed multi-agent control system for the implementation of distributed computing allows in a short time to organize using of the processing power of computers any existing network to solve large-task by creating a distributed computing. Agents based on a computer network can: configure a distributed computing system; to distribute the computational load among computers operated agents; perform optimization distributed computing system according to the computing power of computers on the network. The number of computers connected to the network can be increased by connecting computers to the new computer system, which leads to an increase in overall processing power. Adding multi-agent system in the central agent increases the security of distributed computing. This organization of the distributed computing system reduces the problem solving time and increase fault tolerance (vitality) of computing processes in a changing computing environment (dynamic change of the number of computers on the network). Developed a multi-agent system detects cases of falsification of the results of a distributed system, which may lead to wrong decisions. In addition, the system checks and corrects wrong results.

Blind Quantum Signature with Blind Quantum Computation

NASA Astrophysics Data System (ADS)

Li, Wei; Shi, Ronghua; Guo, Ying

2017-04-01

Blind quantum computation allows a client without quantum abilities to interact with a quantum server to perform a unconditional secure computing protocol, while protecting client's privacy. Motivated by confidentiality of blind quantum computation, a blind quantum signature scheme is designed with laconic structure. Different from the traditional signature schemes, the signing and verifying operations are performed through measurement-based quantum computation. Inputs of blind quantum computation are securely controlled with multi-qubit entangled states. The unique signature of the transmitted message is generated by the signer without leaking information in imperfect channels. Whereas, the receiver can verify the validity of the signature using the quantum matching algorithm. The security is guaranteed by entanglement of quantum system for blind quantum computation. It provides a potential practical application for e-commerce in the cloud computing and first-generation quantum computation.

Flight control systems development of highly maneuverable aircraft technology /HiMAT/ vehicle

NASA Technical Reports Server (NTRS)

Petersen, K. L.

1979-01-01

The highly maneuverable aircraft technology (HiMAT) program was conceived to demonstrate advanced technology concepts through scaled-aircraft flight tests using a remotely piloted technique. Closed-loop primary flight control is performed from a ground-based cockpit, utilizing a digital computer and up/down telemetry links. A backup flight control system for emergency operation resides in an onboard computer. The onboard systems are designed to provide fail-operational capabilities and utilize two microcomputers, dual uplink receiver/decoders, and redundant hydraulic actuation and power systems. This paper discusses the design and validation of the primary and backup digital flight control systems as well as the unique pilot and specialized systems interfaces.

Demodulation of messages received with low signal to noise ratio

NASA Astrophysics Data System (ADS)

Marguinaud, A.; Quignon, T.; Romann, B.

The implementation of this all-digital demodulator is derived from maximum likelihood considerations applied to an analytical representation of the received signal. Traditional adapted filters and phase lock loops are replaced by minimum variance estimators and hypothesis tests. These statistical tests become very simple when working on phase signal. These methods, combined with rigorous control data representation allow significant computation savings as compared to conventional realizations. Nominal operation has been verified down to energetic signal over noise of -3 dB upon a QPSK demodulator.

Demonstration program for Omega receiver prototype microcomputer data processing

NASA Technical Reports Server (NTRS)

Lilley, R. W.

1976-01-01

The JOLT (TM) commercial microcomputer, based on the MOS Technology 6502 processor chip, for use in Omega navigation system is evaluated. A computer program was prepared in hand-assembled code to demonstrate receiver operation. The processor provides binary processing with interrupts enabled, a carriage return is given to initialize the teleprinter, and a jump is performed to enter the program loop to wait for an interrupt. The program loop operates continuously testing the interrupt flag. The interrupt routine reads the receiver status word and determines whether the current time-slot is the A slot. If so, the interrupt flag, which is also the data index pointer, is reset to zero. The status word is stored in the status buffer. If the time-slot is not A, the interrupt flag/pointer is incremented by one to index the phase and status to the proper buffer words for later use by the print routine.

Increasing throughput of multiplexed electrical bus in pipe-lined architecture

DOEpatents

Asaad, Sameh; Brezzo, Bernard V; Kapur, Mohit

2014-05-27

Techniques are disclosed for increasing the throughput of a multiplexed electrical bus by exploiting available pipeline stages of a computer or other system. For example, a method for increasing a throughput of an electrical bus that connects at least two devices in a system comprises introducing at least one signal hold stage in a signal-receiving one of the two devices, such that a maximum frequency at which the two devices are operated is not limited by a number of cycles of an operating frequency of the electrical bus needed for a signal to propagate from a signal-transmitting one of the two devices to the signal-receiving one of the two devices. Preferably, the signal hold stage introduced in the signal-receiving one of the two devices is a pipeline stage re-allocated from the signal-transmitting one of the two devices.

Steady-state and dynamic characteristics of a 20-kHz spacecraft power system - Control of harmonic resonance

NASA Technical Reports Server (NTRS)

Wasynczuk, O.; Krause, P. C.; Biess, J. J.; Kapustka, R.

1990-01-01

A detailed computer simulation was used to illustrate the steady-state and dynamic operating characteristics of a 20-kHz resonant spacecraft power system. The simulated system consists of a parallel-connected set of DC-inductor resonant inverters (drivers), a 440-V cable, a node transformer, a 220-V cable, and a transformer-rectifier-filter (TRF) AC-to-DC receiver load. Also included in the system are a 1-kW 0.8-pf RL load and a double-LC filter connected at the receiving end of the 20-kHz AC system. The detailed computer simulation was used to illustrate the normal steady-state operating characteristics and the dynamic system performance following, for example, TRF startup. It is shown that without any filtering the given system exhibits harmonic resonances due to an interaction between the switching of the source and/or load converters and the AC system. However, the double-LC filter at the receiving-end of the AC system and harmonic traps connected in series with each of the drivers significantly reduce the harmonic distortion of the 20-kHz bus voltage. Significant additional improvement in the waveform quality can be achieved by including a double-LC filter with each driver.

A new strategic neurosurgical planning tool for brainstem cavernous malformations using interactive computer graphics with multimodal fusion images.

PubMed

Kin, Taichi; Nakatomi, Hirofumi; Shojima, Masaaki; Tanaka, Minoru; Ino, Kenji; Mori, Harushi; Kunimatsu, Akira; Oyama, Hiroshi; Saito, Nobuhito

2012-07-01

In this study, the authors used preoperative simulation employing 3D computer graphics (interactive computer graphics) to fuse all imaging data for brainstem cavernous malformations. The authors evaluated whether interactive computer graphics or 2D imaging correlated better with the actual operative field, particularly in identifying a developmental venous anomaly (DVA). The study population consisted of 10 patients scheduled for surgical treatment of brainstem cavernous malformations. Data from preoperative imaging (MRI, CT, and 3D rotational angiography) were automatically fused using a normalized mutual information method, and then reconstructed by a hybrid method combining surface rendering and volume rendering methods. With surface rendering, multimodality and multithreshold techniques for 1 tissue were applied. The completed interactive computer graphics were used for simulation of surgical approaches and assumed surgical fields. Preoperative diagnostic rates for a DVA associated with brainstem cavernous malformation were compared between conventional 2D imaging and interactive computer graphics employing receiver operating characteristic (ROC) analysis. The time required for reconstruction of 3D images was 3-6 hours for interactive computer graphics. Observation in interactive mode required approximately 15 minutes. Detailed anatomical information for operative procedures, from the craniotomy to microsurgical operations, could be visualized and simulated three-dimensionally as 1 computer graphic using interactive computer graphics. Virtual surgical views were consistent with actual operative views. This technique was very useful for examining various surgical approaches. Mean (±SEM) area under the ROC curve for rate of DVA diagnosis was significantly better for interactive computer graphics (1.000±0.000) than for 2D imaging (0.766±0.091; p<0.001, Mann-Whitney U-test). The authors report a new method for automatic registration of preoperative imaging data from CT, MRI, and 3D rotational angiography for reconstruction into 1 computer graphic. The diagnostic rate of DVA associated with brainstem cavernous malformation was significantly better using interactive computer graphics than with 2D images. Interactive computer graphics was also useful in helping to plan the surgical access corridor.

Special purpose parallel computer architecture for real-time control and simulation in robotic applications

NASA Technical Reports Server (NTRS)

Fijany, Amir (Inventor); Bejczy, Antal K. (Inventor)

1993-01-01

This is a real-time robotic controller and simulator which is a MIMD-SIMD parallel architecture for interfacing with an external host computer and providing a high degree of parallelism in computations for robotic control and simulation. It includes a host processor for receiving instructions from the external host computer and for transmitting answers to the external host computer. There are a plurality of SIMD microprocessors, each SIMD processor being a SIMD parallel processor capable of exploiting fine grain parallelism and further being able to operate asynchronously to form a MIMD architecture. Each SIMD processor comprises a SIMD architecture capable of performing two matrix-vector operations in parallel while fully exploiting parallelism in each operation. There is a system bus connecting the host processor to the plurality of SIMD microprocessors and a common clock providing a continuous sequence of clock pulses. There is also a ring structure interconnecting the plurality of SIMD microprocessors and connected to the clock for providing the clock pulses to the SIMD microprocessors and for providing a path for the flow of data and instructions between the SIMD microprocessors. The host processor includes logic for controlling the RRCS by interpreting instructions sent by the external host computer, decomposing the instructions into a series of computations to be performed by the SIMD microprocessors, using the system bus to distribute associated data among the SIMD microprocessors, and initiating activity of the SIMD microprocessors to perform the computations on the data by procedure call.

Analyzing the security of an existing computer system

NASA Technical Reports Server (NTRS)

Bishop, M.

1986-01-01

Most work concerning secure computer systems has dealt with the design, verification, and implementation of provably secure computer systems, or has explored ways of making existing computer systems more secure. The problem of locating security holes in existing systems has received considerably less attention; methods generally rely on thought experiments as a critical step in the procedure. The difficulty is that such experiments require that a large amount of information be available in a format that makes correlating the details of various programs straightforward. This paper describes a method of providing such a basis for the thought experiment by writing a special manual for parts of the operating system, system programs, and library subroutines.

Two-dimensional radiant energy array computers and computing devices

NASA Technical Reports Server (NTRS)

Schaefer, D. H.; Strong, J. P., III (Inventor)

1976-01-01

Two dimensional digital computers and computer devices operate in parallel on rectangular arrays of digital radiant energy optical signal elements which are arranged in ordered rows and columns. Logic gate devices receive two input arrays and provide an output array having digital states dependent only on the digital states of the signal elements of the two input arrays at corresponding row and column positions. The logic devices include an array of photoconductors responsive to at least one of the input arrays for either selectively accelerating electrons to a phosphor output surface, applying potentials to an electroluminescent output layer, exciting an array of discrete radiant energy sources, or exciting a liquid crystal to influence crystal transparency or reflectivity.

Digital Doppler measurement with spacecraft

NASA Technical Reports Server (NTRS)

Kinman, Peter W.; Hinedi, Sami M.; Labelle, Remi C.; Bevan, Roland P.; Del Castillo, Hector M.; Chong, Dwayne C.

1991-01-01

Digital and analog phase-locked loop (PLL) receivers were operated in parallel, each tracking the residual carrier from a spacecraft. The PLL tracked the downlink carrier and measured its instantaneous phase. This information, combined with a knowledge of the uplink carrier and the transponder ratio, permitted the computation of a Doppler observable. In this way, two separate Doppler measurements were obtained for one observation window. The two receivers agreed on the magnitude of the Doppler effect to within 1 mHz. There was less jitter on the data from the digital receiver. This was due to its smaller noise bandwidth. The demonstration and its results are described.

A program for computing the prediction probability and the related receiver operating characteristic graph.

PubMed

Jordan, Denis; Steiner, Marcel; Kochs, Eberhard F; Schneider, Gerhard

2010-12-01

Prediction probability (P(K)) and the area under the receiver operating characteristic curve (AUC) are statistical measures to assess the performance of anesthetic depth indicators, to more precisely quantify the correlation between observed anesthetic depth and corresponding values of a monitor or indicator. In contrast to many other statistical tests, they offer several advantages. First, P(K) and AUC are independent from scale units and assumptions on underlying distributions. Second, the calculation can be performed without any knowledge about particular indicator threshold values, which makes the test more independent from specific test data. Third, recent approaches using resampling methods allow a reliable comparison of P(K) or AUC of different indicators of anesthetic depth. Furthermore, both tests allow simple interpretation, whereby results between 0 and 1 are related to the probability, how good an indicator separates the observed levels of anesthesia. For these reasons, P(K) and AUC have become popular in medical decision making. P(K) is intended for polytomous patient states (i.e., >2 anesthetic levels) and can be considered as a generalization of the AUC, which was basically introduced to assess a predictor of dichotomous classes (e.g., consciousness and unconsciousness in anesthesia). Dichotomous paradigms provide equal values of P(K) and AUC test statistics. In the present investigation, we introduce a user-friendly computer program for computing P(K) and estimating reliable bootstrap confidence intervals. It is designed for multiple comparisons of the performance of depth of anesthesia indicators. Additionally, for dichotomous classes, the program plots the receiver operating characteristic graph completing information obtained from P(K) or AUC, respectively. In clinical investigations, both measures are applied for indicator assessment, where ambiguous usage and interpretation may be a consequence. Therefore, a summary of the concepts of P(K) and AUC including brief and easily understandable proof of their equality is presented in the text. The exposure introduces readers to the algorithms of the provided computer program and is intended to make standardized performance tests of depth of anesthesia indicators available to medical researchers.

Results of the 2016 International Skin Imaging Collaboration International Symposium on Biomedical Imaging challenge: Comparison of the accuracy of computer algorithms to dermatologists for the diagnosis of melanoma from dermoscopic images.

PubMed

Marchetti, Michael A; Codella, Noel C F; Dusza, Stephen W; Gutman, David A; Helba, Brian; Kalloo, Aadi; Mishra, Nabin; Carrera, Cristina; Celebi, M Emre; DeFazio, Jennifer L; Jaimes, Natalia; Marghoob, Ashfaq A; Quigley, Elizabeth; Scope, Alon; Yélamos, Oriol; Halpern, Allan C

2018-02-01

Computer vision may aid in melanoma detection. We sought to compare melanoma diagnostic accuracy of computer algorithms to dermatologists using dermoscopic images. We conducted a cross-sectional study using 100 randomly selected dermoscopic images (50 melanomas, 44 nevi, and 6 lentigines) from an international computer vision melanoma challenge dataset (n = 379), along with individual algorithm results from 25 teams. We used 5 methods (nonlearned and machine learning) to combine individual automated predictions into "fusion" algorithms. In a companion study, 8 dermatologists classified the lesions in the 100 images as either benign or malignant. The average sensitivity and specificity of dermatologists in classification was 82% and 59%. At 82% sensitivity, dermatologist specificity was similar to the top challenge algorithm (59% vs. 62%, P = .68) but lower than the best-performing fusion algorithm (59% vs. 76%, P = .02). Receiver operating characteristic area of the top fusion algorithm was greater than the mean receiver operating characteristic area of dermatologists (0.86 vs. 0.71, P = .001). The dataset lacked the full spectrum of skin lesions encountered in clinical practice, particularly banal lesions. Readers and algorithms were not provided clinical data (eg, age or lesion history/symptoms). Results obtained using our study design cannot be extrapolated to clinical practice. Deep learning computer vision systems classified melanoma dermoscopy images with accuracy that exceeded some but not all dermatologists. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

The Effects of Training, Feedback, and Participant Involvement in Behavioral Safety Observations on Office Ergonomic Behavior

ERIC Educational Resources Information Center

Sasson, Joseph R.; Austin, John

2005-01-01

Eleven computer terminal operators participated in an experiment that assessed effects of several interventions aimed at increasing safe ergonomic performance. All participants received ergonomics training and performance feedback while six of them collected observations of safe behavior among the remaining five participants. Effects of…

7 CFR 3203.3 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-01-01

... repair or enhance its operability. City, town, or local government entity in a rural area as defined in 7...) and fax machines. This term may also include computer software where the transfer of a license is... government entity located in a rural area as defined in 7 U.S.C. 1991(a)(13)(A) that may receive excess...

Near Theoretical Gigabit Link Efficiency for Distributed Data Acquisition Systems

PubMed Central

Abu-Nimeh, Faisal T.; Choong, Woon-Seng

2017-01-01

Link efficiency, data integrity, and continuity for high-throughput and real-time systems is crucial. Most of these applications require specialized hardware and operating systems as well as extensive tuning in order to achieve high efficiency. Here, we present an implementation of gigabit Ethernet data streaming which can achieve 99.26% link efficiency while maintaining no packet losses. The design and implementation are built on OpenPET, an opensource data acquisition platform for nuclear medical imaging, where (a) a crate hosting multiple OpenPET detector boards uses a User Datagram Protocol over Internet Protocol (UDP/IP) Ethernet soft-core, that is capable of understanding PAUSE frames, to stream data out to a computer workstation; (b) the receiving computer uses Netmap to allow the processing software (i.e., user space), which is written in Python, to directly receive and manage the network card’s ring buffers, bypassing the operating system kernel’s networking stack; and (c) a multi-threaded application using synchronized queues is implemented in the processing software (Python) to free up the ring buffers as quickly as possible while preserving data integrity and flow continuity. PMID:28630948

Near Theoretical Gigabit Link Efficiency for Distributed Data Acquisition Systems.

PubMed

Abu-Nimeh, Faisal T; Choong, Woon-Seng

2017-03-01

Link efficiency, data integrity, and continuity for high-throughput and real-time systems is crucial. Most of these applications require specialized hardware and operating systems as well as extensive tuning in order to achieve high efficiency. Here, we present an implementation of gigabit Ethernet data streaming which can achieve 99.26% link efficiency while maintaining no packet losses. The design and implementation are built on OpenPET, an opensource data acquisition platform for nuclear medical imaging, where (a) a crate hosting multiple OpenPET detector boards uses a User Datagram Protocol over Internet Protocol (UDP/IP) Ethernet soft-core, that is capable of understanding PAUSE frames, to stream data out to a computer workstation; (b) the receiving computer uses Netmap to allow the processing software (i.e., user space), which is written in Python, to directly receive and manage the network card's ring buffers, bypassing the operating system kernel's networking stack; and (c) a multi-threaded application using synchronized queues is implemented in the processing software (Python) to free up the ring buffers as quickly as possible while preserving data integrity and flow continuity.

Biosensors with Built-In Biomolecular Logic Gates for Practical Applications

PubMed Central

Lai, Yu-Hsuan; Sun, Sin-Cih; Chuang, Min-Chieh

2014-01-01

Molecular logic gates, designs constructed with biological and chemical molecules, have emerged as an alternative computing approach to silicon-based logic operations. These molecular computers are capable of receiving and integrating multiple stimuli of biochemical significance to generate a definitive output, opening a new research avenue to advanced diagnostics and therapeutics which demand handling of complex factors and precise control. In molecularly gated devices, Boolean logic computations can be activated by specific inputs and accurately processed via bio-recognition, bio-catalysis, and selective chemical reactions. In this review, we survey recent advances of the molecular logic approaches to practical applications of biosensors, including designs constructed with proteins, enzymes, nucleic acids, nanomaterials, and organic compounds, as well as the research avenues for future development of digitally operating “sense and act” schemes that logically process biochemical signals through networked circuits to implement intelligent control systems. PMID:25587423

A ground-based memory state tracker for satellite on-board computer memory

NASA Technical Reports Server (NTRS)

Quan, Alan; Angelino, Robert; Hill, Michael; Schwuttke, Ursula; Hervias, Felipe

1993-01-01

The TOPEX/POSEIDON satellite, currently in Earth orbit, will use radar altimetry to measure sea surface height over 90 percent of the world's ice-free oceans. In combination with a precise determination of the spacecraft orbit, the altimetry data will provide maps of ocean topography, which will be used to calculate the speed and direction of ocean currents worldwide. NASA's Jet Propulsion Laboratory (JPL) has primary responsibility for mission operations for TOPEX/POSEIDON. Software applications have been developed to automate mission operations tasks. This paper describes one of these applications, the Memory State Tracker, which allows the ground analyst to examine and track the contents of satellite on-board computer memory quickly and efficiently, in a human-readable format, without having to receive the data directly from the spacecraft. This process is accomplished by maintaining a groundbased mirror-image of spacecraft On-board Computer memory.

The advanced receiver 2: Telemetry test results in CTA 21

NASA Technical Reports Server (NTRS)

Hinedi, S.; Bevan, R.; Marina, M.

1991-01-01

Telemetry tests with the Advanced Receiver II (ARX II) in Compatibility Test Area 21 are described. The ARX II was operated in parallel with a Block-III Receiver/baseband processor assembly combination (BLK-III/BPA) and a Block III Receiver/subcarrier demodulation assembly/symbol synchronization assembly combination (BLK-III/SDA/SSA). The telemetry simulator assembly provided the test signal for all three configurations, and the symbol signal to noise ratio as well as the symbol error rates were measured and compared. Furthermore, bit error rates were also measured by the system performance test computer for all three systems. Results indicate that the ARX-II telemetry performance is comparable and sometimes superior to the BLK-III/BPA and BLK-III/SDA/SSA combinations.

Neutron Particle Effects on a Quad-Redundant Flight Control Computer

NASA Technical Reports Server (NTRS)

Eure, Kenneth; Belcastro, Celeste M.; Gray, W Steven; Gonzalex, Oscar

2003-01-01

This paper describes a single-event upset experiment performed at the Los Alamos National Laboratory. A closed-loop control system consisting of a Quad-Redundant Flight Control Computer (FCC) and a B737 simulator was operated while the FCC was exposed to a neutron beam. The purpose of this test was to analyze the effects of neutron bombardment on avionics control systems operating at altitudes where neutron strikes are probable. The neutron energy spectrum produced at the Los Alamos National Laboratory is similar in shape to the spectrum of atmospheric neutrons but much more intense. The higher intensity results in accelerated life tests that are representative of the actual neutron radiation that a FCC may receive over a period of years.

Prediction of 5-year overall survival in cervical cancer patients treated with radical hysterectomy using computational intelligence methods.

PubMed

Obrzut, Bogdan; Kusy, Maciej; Semczuk, Andrzej; Obrzut, Marzanna; Kluska, Jacek

2017-12-12

Computational intelligence methods, including non-linear classification algorithms, can be used in medical research and practice as a decision making tool. This study aimed to evaluate the usefulness of artificial intelligence models for 5-year overall survival prediction in patients with cervical cancer treated by radical hysterectomy. The data set was collected from 102 patients with cervical cancer FIGO stage IA2-IIB, that underwent primary surgical treatment. Twenty-three demographic, tumor-related parameters and selected perioperative data of each patient were collected. The simulations involved six computational intelligence methods: the probabilistic neural network (PNN), multilayer perceptron network, gene expression programming classifier, support vector machines algorithm, radial basis function neural network and k-Means algorithm. The prediction ability of the models was determined based on the accuracy, sensitivity, specificity, as well as the area under the receiver operating characteristic curve. The results of the computational intelligence methods were compared with the results of linear regression analysis as a reference model. The best results were obtained by the PNN model. This neural network provided very high prediction ability with an accuracy of 0.892 and sensitivity of 0.975. The area under the receiver operating characteristics curve of PNN was also high, 0.818. The outcomes obtained by other classifiers were markedly worse. The PNN model is an effective tool for predicting 5-year overall survival in cervical cancer patients treated with radical hysterectomy.

Quantity and location of aortic valve complex calcification predicts severity and location of paravalvular regurgitation and frequency of post-dilation after balloon-expandable transcatheter aortic valve replacement.

PubMed

Khalique, Omar K; Hahn, Rebecca T; Gada, Hemal; Nazif, Tamim M; Vahl, Torsten P; George, Isaac; Kalesan, Bindu; Forster, Molly; Williams, Mathew B; Leon, Martin B; Einstein, Andrew J; Pulerwitz, Todd C; Pearson, Gregory D N; Kodali, Susheel K

2014-08-01

This study sought to determine the impact of quantity and location of aortic valve calcification (AVC) on paravalvular regurgitation (PVR) and rates of post-dilation (PD) immediately after transcatheter aortic valve replacement (TAVR). The impact of AVC in different locations within the aortic valve complex is incompletely understood. This study analyzed 150 patients with severe, symptomatic aortic stenosis who underwent TAVR. Total AVC volume scores were calculated from contrast-enhanced multidetector row computed tomography imaging. AVC was divided by leaflet sector and region (Leaflet, Annulus, left ventricular outflow tract [LVOT]), and a combination of LVOT and Annulus (AnnulusLVOT). Asymmetry was assessed. Receiver-operating characteristic analysis was performed with greater than or equal to mild PVR and PD as classification variables. Logistic regression was performed. Quantity of and asymmetry of AVC for all regions of the aortic valve complex predicted greater than or equal to mild PVR by receiver-operating characteristic analysis (area under the curve = 0.635 to 0.689), except Leaflet asymmetry. Receiver-operating characteristic analysis for PD was significant for quantity and asymmetry of AVC in all regions, with higher area under the curve values than for PVR (area under the curve = 0.648 to 0.741). On multivariable analysis, Leaflet and AnnulusLVOT calcification were independent predictors of both PVR and PD regardless of multidetector row computed tomography area cover index. Quantity and asymmetry of AVC in all regions of the aortic valve complex predict greater than or equal to mild PVR and performance of PD, with the exception of Leaflet asymmetry. Quantity of AnnulusLVOT and Leaflet calcification independently predict PVR and PD when taking into account multidetector row computed tomography area cover index. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Design of Remote GPRS-based Gas Data Monitoring System

NASA Astrophysics Data System (ADS)

Yan, Xiyue; Yang, Jianhua; Lu, Wei

2018-01-01

In order to solve the problem of remote data transmission of gas flowmeter, and realize unattended operation on the spot, an unattended remote monitoring system based on GPRS for gas data is designed in this paper. The slave computer of this system adopts embedded microprocessor to read data of gas flowmeter through rs-232 bus and transfers it to the host computer through DTU. In the host computer, the VB program dynamically binds the Winsock control to receive and parse data. By using dynamic data exchange, the Kingview configuration software realizes history trend curve, real time trend curve, alarm, print, web browsing and other functions.

Earth's external magnetic fields at low orbital altitudes

NASA Technical Reports Server (NTRS)

Klumpar, D. M.

1990-01-01

Under our Jun. 1987 proposal, Magnetic Signatures of Near-Earth Distributed Currents, we proposed to render operational a modeling procedure that had been previously developed to compute the magnetic effects of distributed currents flowing in the magnetosphere-ionosphere system. After adaptation of the software to our computing environment we would apply the model to low altitude satellite orbits and would utilize the MAGSAT data suite to guide the analysis. During the first year, basic computer codes to run model systems of Birkeland and ionospheric currents and several graphical output routines were made operational on a VAX 780 in our research facility. Software performance was evaluated using an input matchstick ionospheric current array, field aligned currents were calculated and magnetic perturbations along hypothetical satellite orbits were calculated. The basic operation of the model was verified. Software routines to analyze and display MAGSAT satellite data in terms of deviations with respect to the earth's internal field were also made operational during the first year effort. The complete set of MAGSAT data to be used for evaluation of the models was received at the end of the first year. A detailed annual report in May 1989 described these first year activities completely. That first annual report is included by reference in this final report. This document summarizes our additional activities during the second year of effort and describes the modeling software, its operation, and includes as an attachment the deliverable computer software specified under the contract.

2nd Generation QUATARA Flight Computer Project

NASA Technical Reports Server (NTRS)

Falker, Jay; Keys, Andrew; Fraticelli, Jose Molina; Capo-Iugo, Pedro; Peeples, Steven

2015-01-01

Single core flight computer boards have been designed, developed, and tested (DD&T) to be flown in small satellites for the last few years. In this project, a prototype flight computer will be designed as a distributed multi-core system containing four microprocessors running code in parallel. This flight computer will be capable of performing multiple computationally intensive tasks such as processing digital and/or analog data, controlling actuator systems, managing cameras, operating robotic manipulators and transmitting/receiving from/to a ground station. In addition, this flight computer will be designed to be fault tolerant by creating both a robust physical hardware connection and by using a software voting scheme to determine the processor's performance. This voting scheme will leverage on the work done for the Space Launch System (SLS) flight software. The prototype flight computer will be constructed with Commercial Off-The-Shelf (COTS) components which are estimated to survive for two years in a low-Earth orbit.

Routing performance analysis and optimization within a massively parallel computer

DOEpatents

Archer, Charles Jens; Peters, Amanda; Pinnow, Kurt Walter; Swartz, Brent Allen

2013-04-16

An apparatus, program product and method optimize the operation of a massively parallel computer system by, in part, receiving actual performance data concerning an application executed by the plurality of interconnected nodes, and analyzing the actual performance data to identify an actual performance pattern. A desired performance pattern may be determined for the application, and an algorithm may be selected from among a plurality of algorithms stored within a memory, the algorithm being configured to achieve the desired performance pattern based on the actual performance data.

Optimization of computations for adjoint field and Jacobian needed in 3D CSEM inversion

NASA Astrophysics Data System (ADS)

Dehiya, Rahul; Singh, Arun; Gupta, Pravin K.; Israil, M.

2017-01-01

We present the features and results of a newly developed code, based on Gauss-Newton optimization technique, for solving three-dimensional Controlled-Source Electromagnetic inverse problem. In this code a special emphasis has been put on representing the operations by block matrices for conjugate gradient iteration. We show how in the computation of Jacobian, the matrix formed by differentiation of system matrix can be made independent of frequency to optimize the operations at conjugate gradient step. The coarse level parallel computing, using OpenMP framework, is used primarily due to its simplicity in implementation and accessibility of shared memory multi-core computing machine to almost anyone. We demonstrate how the coarseness of modeling grid in comparison to source (comp`utational receivers) spacing can be exploited for efficient computing, without compromising the quality of the inverted model, by reducing the number of adjoint calls. It is also demonstrated that the adjoint field can even be computed on a grid coarser than the modeling grid without affecting the inversion outcome. These observations were reconfirmed using an experiment design where the deviation of source from straight tow line is considered. Finally, a real field data inversion experiment is presented to demonstrate robustness of the code.

Atmosphere Explorer control system software (version 2.0)

NASA Technical Reports Server (NTRS)

Mocarsky, W.; Villasenor, A.

1973-01-01

The Atmosphere Explorer Control System (AECS) was developed to provide automatic computer control of the Atmosphere Explorer spacecraft and experiments. The software performs several vital functions, such as issuing commands to the spacecraft and experiments, receiving and processing telemetry data, and allowing for extensive data processing by experiment analysis programs. The AECS was written for a 48K XEROX Data System Sigma 5 computer, and coexists in core with the XDS Real-time Batch Monitor (RBM) executive system. RBM is a flexible operating system designed for a real-time foreground/background environment, and hence is ideally suited for this application. Existing capabilities of RBM have been used as much as possible by AECS to minimize programming redundancy. The most important functions of the AECS are to send commands to the spacecraft and experiments, and to receive, process, and display telemetry data.

Evaluation of computer-aided diagnosis (CAD) software for the detection of lung nodules on multidetector row computed tomography (MDCT): JAFROC study for the improvement in radiologists' diagnostic accuracy.

PubMed

Hirose, Tomohiro; Nitta, Norihisa; Shiraishi, Junji; Nagatani, Yukihiro; Takahashi, Masashi; Murata, Kiyoshi

2008-12-01

The aim of this study was to evaluate the usefulness of computer-aided diagnosis (CAD) software for the detection of lung nodules on multidetector-row computed tomography (MDCT) in terms of improvement in radiologists' diagnostic accuracy in detecting lung nodules, using jackknife free-response receiver-operating characteristic (JAFROC) analysis. Twenty-one patients (6 without and 15 with lung nodules) were selected randomly from 120 consecutive thoracic computed tomographic examinations. The gold standard for the presence or absence of nodules in the observer study was determined by consensus of two radiologists. Six expert radiologists participated in a free-response receiver operating characteristic study for the detection of lung nodules on MDCT, in which cases were interpreted first without and then with the output of CAD software. Radiologists were asked to indicate the locations of lung nodule candidates on the monitor with their confidence ratings for the presence of lung nodules. The performance of the CAD software indicated that the sensitivity in detecting lung nodules was 71.4%, with 0.95 false-positive results per case. When radiologists used the CAD software, the average sensitivity improved from 39.5% to 81.0%, with an increase in the average number of false-positive results from 0.14 to 0.89 per case. The average figure-of-merit values for the six radiologists were 0.390 without and 0.845 with the output of the CAD software, and there was a statistically significant difference (P < .0001) using the JAFROC analysis. The CAD software for the detection of lung nodules on MDCT has the potential to assist radiologists by increasing their accuracy.

New instrumentation for the 1.2m Southern Millimeter Wave Telescope (SMWT)

NASA Astrophysics Data System (ADS)

Vasquez, P.; Astudillo, P.; Rodriguez, R.; Monasterio, D.; Reyes, N.; Finger, R.; Mena, F. P.; Bronfman, L.

2016-07-01

Here we describe the status of the upgrade program that is being performed to modernize the Southern 1.2m Wave Telescope. The Telescope was built during early ´80 to complete the first Galactic survey of Molecular Clouds in the CO(1-0) line. After a fruitful operation in CTIO the telescope was relocated to the Universidad de Chile, Cerro Calán Observatory. The new site has an altitude of 850m and allows observations in the millimeter range throughout the year. The telescope was upgraded, including a new building to house operations, new control system, and new receiver and back-end technologies. The new front end is a sideband-separating receiver based on a HEMT amplifier and sub-harmonic mixers. It is cooled with Liquid Nitrogen to diminish its noise temperature. The back-end is a digital spectrometer, based on the Reconfigurable Open Architecture Computing Hardware (ROACH). The new spectrometer includes IF hybridization capabilities to avoid analog hybrids and, therefore, improve the sideband rejection ratio of the receiver.

Establishing a group of endpoints to support collective operations without specifying unique identifiers for any endpoints

DOEpatents

Archer, Charles J.; Blocksom, Michael A.; Ratterman, Joseph D.; Smith, Brian E.; Xue, Hanghon

2016-02-02

A parallel computer executes a number of tasks, each task includes a number of endpoints and the endpoints are configured to support collective operations. In such a parallel computer, establishing a group of endpoints receiving a user specification of a set of endpoints included in a global collection of endpoints, where the user specification defines the set in accordance with a predefined virtual representation of the endpoints, the predefined virtual representation is a data structure setting forth an organization of tasks and endpoints included in the global collection of endpoints and the user specification defines the set of endpoints without a user specification of a particular endpoint; and defining a group of endpoints in dependence upon the predefined virtual representation of the endpoints and the user specification.

Computational imaging of light in flight

NASA Astrophysics Data System (ADS)

Hullin, Matthias B.

2014-10-01

Many computer vision tasks are hindered by image formation itself, a process that is governed by the so-called plenoptic integral. By averaging light falling into the lens over space, angle, wavelength and time, a great deal of information is irreversibly lost. The emerging idea of transient imaging operates on a time resolution fast enough to resolve non-stationary light distributions in real-world scenes. It enables the discrimination of light contributions by the optical path length from light source to receiver, a dimension unavailable in mainstream imaging to date. Until recently, such measurements used to require high-end optical equipment and could only be acquired under extremely restricted lab conditions. To address this challenge, we introduced a family of computational imaging techniques operating on standard time-of-flight image sensors, for the first time allowing the user to "film" light in flight in an affordable, practical and portable way. Just as impulse responses have proven a valuable tool in almost every branch of science and engineering, we expect light-in-flight analysis to impact a wide variety of applications in computer vision and beyond.

Synchronization techniques for all digital 16-ary QAM receivers operating over land mobile satellite links

NASA Technical Reports Server (NTRS)

Fines, P.; Aghvami, A. H.

1990-01-01

The performance of a low bit rate (64 Kb/s) all digital 16-ary Differentially Encoded Quadrature Amplitude Modulation (16-DEQAM) demodulator operating over a mobile satellite channel, is considered. The synchronization and detection techniques employed to overcome the Rician channel impairments, are described. The acquisition and steady state performance of this modem, are evaluated by computer simulation over AWGN and RICIAN channels. The results verify the suitability of the 16-DEQAM transmission over slowly faded and/or mildly faded channels.

Ag-Air Service

NASA Technical Reports Server (NTRS)

1981-01-01

Econ, Inc.'s agricultural aerial application, "ag-air," involves more than 10,000 aircraft spreading insecticides, herbicides, fertilizer, seed and other materials over millions of acres of farmland. Difficult for an operator to estimate costs accurately and decide what to charge or which airplane can handle which assignment most efficiently. Computerized service was designed to improve business efficiency in choice of aircraft and determination of charge rates based on realistic operating cost data. Each subscriber fills out a detailed form which pertains to his needs and then receives a custom-tailored computer printout best suited to his particular business mix.

Interactive signal analysis and ultrasonic data collection system user's manual

NASA Technical Reports Server (NTRS)

Smith, G. R.

1978-01-01

The interactive signal analysis and ultrasonic data collection system (ECHO1) is a real time data acquisition and display system. ECHO1 executed on a PDP-11/45 computer under the RT11 real time operating system. Extensive operator interaction provided the requisite parameters to the data collection, calculation, and data modules. Data were acquired in real time from a pulse echo ultrasonic system using a Biomation Model 8100 transient recorder. The data consisted of 2084 intensity values representing the amplitude of pulses transmitted and received by the ultrasonic unit.

User guide to a command and control system; a part of a prelaunch wind monitoring program

NASA Technical Reports Server (NTRS)

Cowgill, G. R.

1976-01-01

A set of programs called Command and Control System (CCS), intended as a user manual, is described for the operation of CCS by the personnel supporting the wind monitoring portion of the launch mission. Wind data obtained by tracking balloons is sent by electronic means using telephone lines to other locations. Steering commands are computed from a system called ADDJUST for the on-board computer and relays this data. Data are received and automatically stored in a microprocessor, then via a real time program transferred to the UNIVAC 1100/40 computer. At this point the data is available to be used by the Command and Control system.

Mariner 9 television pictures: Microfiche library user's guide. MTC/MTVS real-time pictures

NASA Technical Reports Server (NTRS)

Becker, R. A.

1973-01-01

This document describes the content and organization of the Mariner 9 Mission Test Computer/Mission Test Video System microfiche library. This 775 card library is intended to supply the user with a complete record of the images received from Mars orbit during the Mariner 9 mission operations, from 15 Nov. 1971 to 1 Nov. 1972.

Support for User Interfaces for Distributed Systems

NASA Technical Reports Server (NTRS)

Eychaner, Glenn; Niessner, Albert

2005-01-01

An extensible Java(TradeMark) software framework supports the construction and operation of graphical user interfaces (GUIs) for distributed computing systems typified by ground control systems that send commands to, and receive telemetric data from, spacecraft. Heretofore, such GUIs have been custom built for each new system at considerable expense. In contrast, the present framework affords generic capabilities that can be shared by different distributed systems. Dynamic class loading, reflection, and other run-time capabilities of the Java language and JavaBeans component architecture enable the creation of a GUI for each new distributed computing system with a minimum of custom effort. By use of this framework, GUI components in control panels and menus can send commands to a particular distributed system with a minimum of system-specific code. The framework receives, decodes, processes, and displays telemetry data; custom telemetry data handling can be added for a particular system. The framework supports saving and later restoration of users configurations of control panels and telemetry displays with a minimum of effort in writing system-specific code. GUIs constructed within this framework can be deployed in any operating system with a Java run-time environment, without recompilation or code changes.

Discrimination Between Patients With Alzheimer Disease and Healthy Subjects Using Layer Analysis of Cerebral Blood Flow and Xenon Solubility Coefficient in Xenon-Enhanced Computed Tomography.

PubMed

Sase, Shigeru; Yamamoto, Homaro; Kawashima, Ena; Tan, Xin; Sawa, Yutaka

The aim of this study was to develop a method for discriminating between patients with Alzheimer disease (AD) and healthy subjects using layer analysis of cerebral blood flow (CBF) and xenon solubility coefficient (λ) in xenon-enhanced computed tomography (CT). Xenon-enhanced CT was performed on 27 patients with AD (81.7 [3.3] years old) and 15 healthy volunteers (78.6 [4.0] years old) using a wide volume CT. For each subject, we created the first- (surface) to sixth-layer images of CBF and λ for the 6 viewing directions (layer thickness, 5 mm). For the discriminant views, receiver operating characteristic curves for the ratio of CBF to λ were created to identify patients with AD. For the third- and fourth-layer left lateral views, which were designated as the discriminant views, areas under the receiver operating characteristic curve were 96.8% and 97.4%, respectively. With the use of the discriminant views obtained by xenon-enhanced CT, we could effectively discriminate between patients with AD and healthy subjects using both CBF and λ.

Timing of Occurrence Is the Most Important Characteristic of Spot Sign.

PubMed

Wang, Binli; Yan, Shenqiang; Xu, Mengjun; Zhang, Sheng; Liu, Keqin; Hu, Haitao; Selim, Magdy; Lou, Min

2016-05-01

Most previous studies have used single-phase computed tomographic angiography to detect the spot sign, a marker for hematoma expansion (HE) in spontaneous intracerebral hemorrhage. We investigated whether defining the spot sign based on timing on perfusion computed tomography (CTP) would improve its specificity for predicting HE. We prospectively enrolled supratentorial spontaneous intracerebral hemorrhage patients who underwent CTP within 6 hours of onset. Logistic regression was performed to assess the risk factors for HE and poor outcome. Predictive performance of individual CTP spot sign characteristics were examined with receiver operating characteristic analysis. Sixty-two men and 21 women with spontaneous intracerebral hemorrhage were included in this analysis. Spot sign was detected in 46% (38/83) of patients. Receiver operating characteristic analysis indicated that the timing of spot sign occurrence on CTP had the greatest area under receiver operating characteristic curve for HE (0.794; 95% confidence interval, 0.630-0.958; P=0.007); the cutoff time was 23.13 seconds. On multivariable analysis, the presence of early-occurring spot sign (ie, spot sign before 23.13 seconds) was an independent predictor not only of HE (odds ratio=28.835; 95% confidence interval, 6.960-119.458; P<0.001), but also of mortality at 3 months (odds ratio =22.377; 95% confidence interval, 1.773-282.334; P=0.016). Moreover, the predictive performance showed that the redefined early-occurring spot sign maintained a higher specificity for HE compared with spot sign (91% versus 74%). Redefining the spot sign based on timing of contrast leakage on CTP to determine early-occurring spot sign improves the specificity for predicting HE and 3-month mortality. The use of early-occurring spot sign could improve the selection of ICH patients for potential hemostatic therapy. © 2016 American Heart Association, Inc.

Experimental Design and Data Analysis in Receiver Operating Characteristic Studies: Lessons Learned from Reports in Radiology from 1997 to 20061

PubMed Central

Shiraishi, Junji; Pesce, Lorenzo L.; Metz, Charles E.; Doi, Kunio

2009-01-01

Purpose: To provide a broad perspective concerning the recent use of receiver operating characteristic (ROC) analysis in medical imaging by reviewing ROC studies published in Radiology between 1997 and 2006 for experimental design, imaging modality, medical condition, and ROC paradigm. Materials and Methods: Two hundred ninety-five studies were obtained by conducting a literature search with PubMed with two criteria: publication in Radiology between 1997 and 2006 and occurrence of the phrase “receiver operating characteristic.” Studies returned by the query that were not diagnostic imaging procedure performance evaluations were excluded. Characteristics of the remaining studies were tabulated. Results: Two hundred thirty-three (79.0%) of the 295 studies reported findings based on observers' diagnostic judgments or objective measurements. Forty-three (14.6%) did not include human observers, with most of these reporting an evaluation of a computer-aided diagnosis system or functional data obtained with computed tomography (CT) or magnetic resonance (MR) imaging. The remaining 19 (6.4%) studies were classified as reviews or meta-analyses and were excluded from our subsequent analysis. Among the various imaging modalities, MR imaging (46.0%) and CT (25.7%) were investigated most frequently. Approximately 60% (144 of 233) of ROC studies with human observers published in Radiology included three or fewer observers. Conclusion: ROC analysis is widely used in radiologic research, confirming its fundamental role in assessing diagnostic performance. However, the ROC studies reported in Radiology were not always adequate to support clear and clinically relevant conclusions. © RSNA, 2009 Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.2533081632/-/DC1 PMID:19864510

Adaptation of a Control Center Development Environment for Industrial Process Control

NASA Technical Reports Server (NTRS)

Killough, Ronnie L.; Malik, James M.

1994-01-01

In the control center, raw telemetry data is received for storage, display, and analysis. This raw data must be combined and manipulated in various ways by mathematical computations to facilitate analysis, provide diversified fault detection mechanisms, and enhance display readability. A development tool called the Graphical Computation Builder (GCB) has been implemented which provides flight controllers with the capability to implement computations for use in the control center. The GCB provides a language that contains both general programming constructs and language elements specifically tailored for the control center environment. The GCB concept allows staff who are not skilled in computer programming to author and maintain computer programs. The GCB user is isolated from the details of external subsystem interfaces and has access to high-level functions such as matrix operators, trigonometric functions, and unit conversion macros. The GCB provides a high level of feedback during computation development that improves upon the often cryptic errors produced by computer language compilers. An equivalent need can be identified in the industrial data acquisition and process control domain: that of an integrated graphical development tool tailored to the application to hide the operating system, computer language, and data acquisition interface details. The GCB features a modular design which makes it suitable for technology transfer without significant rework. Control center-specific language elements can be replaced by elements specific to industrial process control.

The calculation of electromagnetic fields in the Fresnel and Fraunhofer regions using numerical integration methods

NASA Technical Reports Server (NTRS)

Schmidt, R. F.

1971-01-01

Some results obtained with a digital computer program written at Goddard Space Flight Center to obtain electromagnetic fields scattered by perfectly reflecting surfaces are presented. For purposes of illustration a paraboloidal reflector was illuminated at radio frequencies in the simulation for both receiving and transmitting modes of operation. Fields were computed in the Fresnel and Fraunhofer regions. A dual-reflector system (Cassegrain) was also simulated for the transmitting case, and fields were computed in the Fraunhofer region. Appended results include derivations which show that the vector Kirchhoff-Kottler formulation has an equivalent form requiring only incident magnetic fields as a driving function. Satisfaction of the radiation conditions at infinity by the equivalent form is demonstrated by a conversion from Cartesian to spherical vector operators. A subsequent development presents the formulation by which Fresnel or Fraunhofer patterns are obtainable for dual-reflector systems. A discussion of the time-average Poynting vector is also appended.

A flexible tool for diagnosing water, energy, and entropy budgets in climate models

NASA Astrophysics Data System (ADS)

Lembo, Valerio; Lucarini, Valerio

2017-04-01

We have developed a new flexible software for studying the global energy budget, the hydrological cycle, and the material entropy production of global climate models. The program receives as input radiative, latent and sensible energy fluxes, with the requirement that the variable names are in agreement with the Climate and Forecast (CF) conventions for the production of NetCDF datasets. Annual mean maps, meridional sections and time series are computed by means of Climate Data Operators (CDO) collection of command line operators developed at Max-Planck Institute for Meteorology (MPI-M). If a land-sea mask is provided, the program also computes the required quantities separately on the continents and oceans. Depending on the user's choice, the program also calls the MATLAB software to compute meridional heat transports and location and intensities of the peaks in the two hemispheres. We are currently planning to adapt the program in order to be included in the Earth System Model eValuation Tool (ESMValTool) community diagnostics.

Optimistic barrier synchronization

NASA Technical Reports Server (NTRS)

Nicol, David M.

1992-01-01

Barrier synchronization is fundamental operation in parallel computation. In many contexts, at the point a processor enters a barrier it knows that it has already processed all the work required of it prior to synchronization. The alternative case, when a processor cannot enter a barrier with the assurance that it has already performed all the necessary pre-synchronization computation, is treated. The problem arises when the number of pre-sychronization messages to be received by a processor is unkown, for example, in a parallel discrete simulation or any other computation that is largely driven by an unpredictable exchange of messages. We describe an optimistic O(log sup 2 P) barrier algorithm for such problems, study its performance on a large-scale parallel system, and consider extensions to general associative reductions as well as associative parallel prefix computations.

Identifying messaging completion in a parallel computer by checking for change in message received and transmitted count at each node

DOEpatents

Archer, Charles J [Rochester, MN; Hardwick, Camesha R [Fayetteville, NC; McCarthy, Patrick J [Rochester, MN; Wallenfelt, Brian P [Eden Prairie, MN

2009-06-23

Methods, parallel computers, and products are provided for identifying messaging completion on a parallel computer. The parallel computer includes a plurality of compute nodes, the compute nodes coupled for data communications by at least two independent data communications networks including a binary tree data communications network optimal for collective operations that organizes the nodes as a tree and a torus data communications network optimal for point to point operations that organizes the nodes as a torus. Embodiments include reading all counters at each node of the torus data communications network; calculating at each node a current node value in dependence upon the values read from the counters at each node; and determining for all nodes whether the current node value for each node is the same as a previously calculated node value for each node. If the current node is the same as the previously calculated node value for all nodes of the torus data communications network, embodiments include determining that messaging is complete and if the current node is not the same as the previously calculated node value for all nodes of the torus data communications network, embodiments include determining that messaging is currently incomplete.

IAA RAS Radio Telescope Monitoring System

NASA Astrophysics Data System (ADS)

Mikhailov, A.; Lavrov, A.

2007-07-01

Institute of Applied Astronomy of the Russian Academy of Sciences (IAA RAS) has three identical radio telescopes, the receiving complex of which consists of five two-channel receivers of different bands, six cryogen systems, and additional devices: four local oscillators, phase calibration generators and IF commutator. The design, hardware and data communication protocol are described. The most convenient way to join the devices of the receiving complex into the common monitoring system is to use the interface which allows to connect numerous devices to the data bus. For the purpose of data communication regulation and to exclude conflicts, a data communication protocol has been designed, which operates with complex formatted data sequences. Formation of such sequences requires considerable data processing capability. That is provided by a microcontroller chip in each slave device. The test version of the software for the central computer has been developed in IAA RAS. We are developing the Mark IV FS software extension modules, which will allow us to control the receiving complex of the radio telescope by special SNAP commands from both operator input and schedule files. We are also developing procedures of automatic measurements of SEFD, system noise temperature and other parameters, available both in VLBI and single-dish modes of operation. The system described has been installed on all IAA RAS radio telescopes at "Svetloe", "Zelenchukskaya" and "Badary" observatories. It has proved to be working quite reliably and to show the perfonmance expected.

A clip-based protocol for breast boost radiotherapy provides clear target visualisation and demonstrates significant volume reduction over time

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lewis, Lorraine; Cox, Jennifer; Faculty of Health Sciences, University of Sydney, Sydney, New South Wales

2015-09-15

The clinical target volume (CTV) for early stage breast cancer is difficult to clearly identify on planning computed tomography (CT) scans. Surgical clips inserted around the tumour bed should help to identify the CTV, particularly if the seroma has been reabsorbed, and enable tracking of CTV changes over time. A surgical clip-based CTV delineation protocol was introduced. CTV visibility and its post-operative shrinkage pattern were assessed. The subjects were 27 early stage breast cancer patients receiving post-operative radiotherapy alone and 15 receiving post-operative chemotherapy followed by radiotherapy. The radiotherapy alone (RT/alone) group received a CT scan at median 25 daysmore » post-operatively (CT1rt) and another at 40 Gy, median 68 days (CT2rt). The chemotherapy/RT group (chemo/RT) received a CT scan at median 18 days post-operatively (CT1ch), a planning CT scan at median 126 days (CT2ch), and another at 40 Gy (CT3ch). There was no significant difference (P = 0.08) between the initial mean CTV for each cohort. The RT/alone cohort showed significant CTV volume reduction of 38.4% (P = 0.01) at 40 Gy. The Chemo/RT cohort had significantly reduced volumes between CT1ch: median 54 cm{sup 3} (4–118) and CT2ch: median 16 cm{sup 3}, (2–99), (P = 0.01), but no significant volume reduction thereafter. Surgical clips enable localisation of the post-surgical seroma for radiotherapy targeting. Most seroma shrinkage occurs early, enabling CT treatment planning to take place at 7 weeks, which is within the 9 weeks recommended to limit disease recurrence.« less

Virtual reality for the treatment of autism.

PubMed

Strickland, D

1997-01-01

Autism is a mental disorder which has received attention in several unrelated studies using virtual reality. One of the first attempts was to diagnose children with special needs at Tokyo University using a sandbox playing technique. Although operating the computer controls proved to be too difficult for the individuals with autism in the Tokyo study, research at the University of Nottingham, UK, is successful in using VR as a learning aid for children with a variety of disorders including autism. Both centers used flat screen computer systems with virtual scenes. Another study which concentrated on using VR as a learning aid with an immersive headset system is described in detail in this chapter. Perhaps because of the seriousness of the disorder and the lack of effective treatments, autism has received more study than attention deficit disorders, although both would appear to benefit from many of the same technology features.

Radio-nuclide mixture identification using medium energy resolution detectors

DOEpatents

Nelson, Karl Einar

2013-09-17

According to one embodiment, a method for identifying radio-nuclides includes receiving spectral data, extracting a feature set from the spectral data comparable to a plurality of templates in a template library, and using a branch and bound method to determine a probable template match based on the feature set and templates in the template library. In another embodiment, a device for identifying unknown radio-nuclides includes a processor, a multi-channel analyzer, and a memory operatively coupled to the processor, the memory having computer readable code stored thereon. The computer readable code is configured, when executed by the processor, to receive spectral data, to extract a feature set from the spectral data comparable to a plurality of templates in a template library, and to use a branch and bound method to determine a probable template match based on the feature set and templates in the template library.

Data communications for a collective operation in a parallel active messaging interface of a parallel computer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Faraj, Daniel A.

Algorithm selection for data communications in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI composed of data communications endpoints, each endpoint including specifications of a client, a context, and a task, endpoints coupled for data communications through the PAMI, including associating in the PAMI data communications algorithms and bit masks; receiving in an origin endpoint of the PAMI a collective instruction, the instruction specifying transmission of a data communications message from the origin endpoint to a target endpoint; constructing a bit mask for the received collective instruction; selecting, from among the associated algorithms and bit masks,more » a data communications algorithm in dependence upon the constructed bit mask; and executing the collective instruction, transmitting, according to the selected data communications algorithm from the origin endpoint to the target endpoint, the data communications message.« less

Data communications for a collective operation in a parallel active messaging interface of a parallel computer

DOEpatents

Faraj, Daniel A

2013-07-16

Algorithm selection for data communications in a parallel active messaging interface (`PAMI`) of a parallel computer, the PAMI composed of data communications endpoints, each endpoint including specifications of a client, a context, and a task, endpoints coupled for data communications through the PAMI, including associating in the PAMI data communications algorithms and bit masks; receiving in an origin endpoint of the PAMI a collective instruction, the instruction specifying transmission of a data communications message from the origin endpoint to a target endpoint; constructing a bit mask for the received collective instruction; selecting, from among the associated algorithms and bit masks, a data communications algorithm in dependence upon the constructed bit mask; and executing the collective instruction, transmitting, according to the selected data communications algorithm from the origin endpoint to the target endpoint, the data communications message.

Method for routing events from key strokes in a multi-processing computer systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rhodes, D.A.; Rustici, E.; Carter, K.H.

1990-01-23

The patent describes a method of routing user input in a computer system which concurrently runs a plurality of processes. It comprises: generating keycodes representative of keys typed by a user; distinguishing generated keycodes by looking up each keycode in a routing table which assigns each possible keycode to an individual assigned process of the plurality of processes, one of which processes being a supervisory process; then, sending each keycode to its assigned process until a keycode assigned to the supervisory process is received; sending keycodes received subsequent to the keycode assigned to the supervisory process to a buffer; next,more » providing additional keycodes to the supervisory process from the buffer until the supervisory process has completed operation; and sending keycodes stored in the buffer to processes assigned therewith after the supervisory process has completedoperation.« less

Respiratory analysis system and method

NASA Technical Reports Server (NTRS)

Liu, F. F. (Inventor)

1973-01-01

A system is described for monitoring the respiratory process in which the gas flow rate and the frequency of respiration and expiration cycles can be determined on a real time basis. A face mask is provided with one-way inlet and outlet valves where the gas flow is through independent flowmeters and through a mass spectrometer. The opening and closing of a valve operates an electrical switch, and the combination of the two switches produces a low frequency electrical signal of the respiratory inhalation and exhalation cycles. During the time a switch is operated, the corresponsing flowmeter produces electric pulses representative of the flow rate; the electrical pulses being at a higher frequency than that of the breathing cycle and combined with the low frequency signal. The high frequency pulses are supplied to conventional analyzer computer which also receives temperature and pressure inputs and computes mass flow rate and totalized mass flow of gas. From the mass spectrometer, components of the gas are separately computed as to flow rate. The electrical switches cause operation of up-down inputs of a reversible counter. The respective up and down cycles can be individually monitored and combined for various respiratory measurements.

Storm Warning Service

NASA Technical Reports Server (NTRS)

1993-01-01

A Huntsville meteorologist of Baron Services, Inc. has formed a commercial weather advisory service. Weather information is based on data from Marshall Space Flight Center (MSFC) collected from antennas in Alabama and Tennessee. Bob Baron refines and enhances MSFC's real time display software. Computer data is changed to audio data for radio transmission, received by clients through an antenna and decoded by computer for display. Using his service, clients can monitor the approach of significant storms and schedule operations accordingly. Utilities and emergency management officials are able to plot a storm's path. A recent agreement with two other companies will promote continued development and marketing.

Solar energy incident at the receiver of a solar tower plant, derived from remote sensing: Computation of both DNI and slant path transmittance

NASA Astrophysics Data System (ADS)

Elias, Thierry; Ramon, Didier; Garnero, Marie-Agnès; Dubus, Laurent; Bourdil, Charles

2017-06-01

By scattering and absorbing solar radiation, aerosols generate production losses in solar plants. Due to the specific design of solar tower plants, solar radiation is attenuated not only in the atmospheric column but also in the slant path between the heliostats and the receiver. Broadband attenuation by aerosols is estimated in both the column and the slant path for Ouarzazate, Morocco, using spectral measurements of aerosol optical thickness (AOT) collected by AERONET. The proportion of AOT below the tower's height is computed assuming a single uniform aerosol layer of height equal to the boundary layer height computed by ECMWF for the Operational Analysis. The monthly average of the broadband attenuation by aerosols in the slant path was 6.9±3.0% in August 2012 at Ouarzazate, for 1-km distance between the heliostat and the receiver. The slant path attenuation should be added to almost 40% attenuation along the atmospheric column, with aerosols in an approximate 4.7-km aerosol layer. Also, around 1.5% attenuation is caused by Rayleigh and water vapour in the slant path. The monochromatic-broadband extrapolation is validated by comparing computed and observed direct normal irradiance (DNI). DNI observed around noon varied from more than 1000 W/m2 to around 400 W/m2 at Ouarzazate in 2012 because of desert dust plumes transported from North African desert areas.

An approach to a real-time distribution system

NASA Technical Reports Server (NTRS)

Kittle, Frank P., Jr.; Paddock, Eddie J.; Pocklington, Tony; Wang, Lui

1990-01-01

The requirements of a real-time data distribution system are to provide fast, reliable delivery of data from source to destination with little or no impact to the data source. In this particular case, the data sources are inside an operational environment, the Mission Control Center (MCC), and any workstation receiving data directly from the operational computer must conform to the software standards of the MCC. In order to supply data to development workstations outside of the MCC, it is necessary to use gateway computers that prevent unauthorized data transfer back to the operational computers. Many software programs produced on the development workstations are targeted for real-time operation. Therefore, these programs must migrate from the development workstation to the operational workstation. It is yet another requirement for the Data Distribution System to ensure smooth transition of the data interfaces for the application developers. A standard data interface model has already been set up for the operational environment, so the interface between the distribution system and the application software was developed to match that model as closely as possible. The system as a whole therefore allows the rapid development of real-time applications without impacting the data sources. In summary, this approach to a real-time data distribution system provides development users outside of the MCC with an interface to MCC real-time data sources. In addition, the data interface was developed with a flexible and portable software design. This design allows for the smooth transition of new real-time applications to the MCC operational environment.

Omega flight-test data reduction sequence. [computer programs for reduction of navigation data

NASA Technical Reports Server (NTRS)

Lilley, R. W.

1974-01-01

Computer programs for Omega data conversion, summary, and preparation for distribution are presented. Program logic and sample data formats are included, along with operational instructions for each program. Flight data (or data collected in flight format in the laboratory) is provided by the Ohio University Omega receiver base in the form of 6-bit binary words representing the phase of an Omega station with respect to the receiver's local clock. All eight Omega stations are measured in each 10-second Omega time frame. In addition, an event-marker bit and a time-slot D synchronizing bit are recorded. Program FDCON is used to remove data from the flight recorder tape and place it on data-processing cards for later use. Program FDSUM provides for computer plotting of selected LOP's, for single-station phase plots, and for printout of basic signal statistics for each Omega channel. Mean phase and standard deviation are printed, along with data from which a phase distribution can be plotted for each Omega station. Program DACOP simply copies the Omega data deck a controlled number of times, for distribution to users.

Structural analysis of a reflux pool-boiler solar receiver

NASA Astrophysics Data System (ADS)

Hoffman, E. L.; Stone, C. M.

1991-06-01

Coupled thermal-structural finite element calculations of a reflux pool-boiler solar receiver were performed to characterize the operating stresses and to address issues affecting the service life of the receiver. Analyses performed using shell elements provided information for receiver material selection and design optimization. Calculations based on linear elastic fracture mechanics principles were performed using continuum elements to assess the vulnerability of a seam-weld to fatigue crack growth. All calculations were performed using ABAQUS, a general purpose finite element code, and elements specifically formulated for coupled thermal-structural analysis. Two materials were evaluated: 316L SS and Haynes 230 alloys. The receiver response was simulated for a combination of structural and thermal loads that represent the startup and operating conditions of the receiver. For both materials, maximum stresses in the receiver developed shortly after startup due to uneven temperature distribution across the receiver surface. The largest effective stress was near yield in the 316L SS receiver and below 39 percent of yield in the Haynes 230 receiver. The calculations demonstrated that stress reductions of over 25 percent could be obtained by reducing the aft dome thickness to one closer to the absorber. The fatigue calculations demonstrated that the stress distribution near the seam-weld notch depends primarily on the structural load created by internal pressurization of the receiver rather than the thermal, indicating that the thermal loads can be neglected when assessing the stress intensity near the seam-weld notch. The stress intensity factor, computed using the J-integral method and crack opening-displacement field equations, was significantly below the fatigue threshold for most steels. The calculations indicated that the weld notch was always loaded in compression, a condition which is not conducive to fatigue crack growth.

Audiometric testing and hearing protection training through multimedia technology.

PubMed

Hong, OiSaeng; Csaszar, Peter

2005-09-01

The purpose of this paper is to present the development process of a computer-based audiometric testing and tailored intervention program, and assess its feasibility by obtaining users' feedback. The program was implemented for 397 operating engineers at their union training center, and its feasibility was evaluated by obtaining quantitative and qualitative feedback from the participants through a survey and focus group. Over 96% of the participants indicated they liked receiving a hearing test by computer; the computer-based test worked smoothly; and the computer-based training was well organized, effective and held their interests. Almost all (more than 99%) said they would recommend this program to other workers. This project is considered as one of the first ones incorporating multimedia computer technology with self-administered audiometric testing and tailored training. Participants' favorable feedback strongly supported the continued utilization of this approach for designing and developing health screening and intervention to promote healthy behaviors.

Distributed metadata in a high performance computing environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bent, John M.; Faibish, Sorin; Zhang, Zhenhua

A computer-executable method, system, and computer program product for managing meta-data in a distributed storage system, wherein the distributed storage system includes one or more burst buffers enabled to operate with a distributed key-value store, the co computer-executable method, system, and computer program product comprising receiving a request for meta-data associated with a block of data stored in a first burst buffer of the one or more burst buffers in the distributed storage system, wherein the meta data is associated with a key-value, determining which of the one or more burst buffers stores the requested metadata, and upon determination thatmore » a first burst buffer of the one or more burst buffers stores the requested metadata, locating the key-value in a portion of the distributed key-value store accessible from the first burst buffer.« less

Application of permanents of square matrices for DNA identification in multiple-fatality cases

PubMed Central

2013-01-01

Background DNA profiling is essential for individual identification. In forensic medicine, the likelihood ratio (LR) is commonly used to identify individuals. The LR is calculated by comparing two hypotheses for the sample DNA: that the sample DNA is identical or related to a reference DNA, and that it is randomly sampled from a population. For multiple-fatality cases, however, identification should be considered as an assignment problem, and a particular sample and reference pair should therefore be compared with other possibilities conditional on the entire dataset. Results We developed a new method to compute the probability via permanents of square matrices of nonnegative entries. As the exact permanent is known as a #P-complete problem, we applied the Huber–Law algorithm to approximate the permanents. We performed a computer simulation to evaluate the performance of our method via receiver operating characteristic curve analysis compared with LR under the assumption of a closed incident. Differences between the two methods were well demonstrated when references provided neither obligate alleles nor impossible alleles. The new method exhibited higher sensitivity (0.188 vs. 0.055) at a threshold value of 0.999, at which specificity was 1, and it exhibited higher area under a receiver operating characteristic curve (0.990 vs. 0.959, P = 9.6E-15). Conclusions Our method therefore offers a solution for a computationally intensive assignment problem and may be a viable alternative to LR-based identification for closed-incident multiple-fatality cases. PMID:23962363

Coupled optical/thermal/fluid analysis and design requirements for operation and testing of a supercritical CO 2 solar receiver.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khivsara, Sagar

Recent studies have evaluated closed-loop supercritical carbon dioxide (s-CO 2) Brayton cycles to be a higher energy-density system in comparison to conventional superheated steam Rankine systems. At turbine inlet conditions of 923K and 25 MPa, high thermal efficiency (~50%) can be achieved. Achieving these high efficiencies will make concentrating solar power (CSP) technologies a competitive alternative to current power generation methods. To incorporate a s-CO 2 Brayton power cycle in a solar power tower system, the development of a solar receiver capable of providing an outlet temperature of 923 K (at 25 MPa) is necessary. To satisfy the temperature requirementsmore » of a s-CO 2 Brayton cycle with recuperation and recompression, it is required to heat s-CO 2 by a temperature of ~200 K as it passes through the solar receiver. Our objective was to develop an optical-thermal-fluid model to design and evaluate a tubular receiver that will receive a heat input ~1 MWth from a heliostat field. We also undertook the documentation of design requirements for the development, testing and safe operation of a direct s-CO 2 solar receiver. The main purpose of this document is to serve as a reference and guideline for design and testing requirements, as well as to address the technical challenges and provide initial parameters for the computational models that will be employed for the development of s-CO 2 receivers.« less

Quiet Short-Haul Research Airplane (QSRA) model select panel functional description

NASA Technical Reports Server (NTRS)

Watson, D. M.

1982-01-01

The QSRA, when equipped with programmable color cathode ray tube displays, a head up display, a general purpose digital computer and a microwave landing system receiver, will provide a capability to do handling qualities studies and terminal area operating systems experiments as well as to enhance an experimenter's ability to obtain repeatable aircraft performance data. The operating systems experiments include the capability to generate minimum fuel approach and departure paths and to conduct precision approaches to a STOLport runway. The mode select panel is designed to provide both the flexibility needed for a variety of flight test experiments and the minimum workload operation required by pilots flying into congested terminal traffic areas.

Control of the TSU 2-m automatic telescope

NASA Astrophysics Data System (ADS)

Eaton, Joel A.; Williamson, Michael H.

2004-09-01

Tennessee State University is operating a 2-m automatic telescope for high-dispersion spectroscopy. The alt-azimuth telescope is fiber-coupled to a conventional echelle spectrograph with two resolutions (R=30,000 and 70,000). We control this instrument with four computers running linux and communicating over ethernet through the UDP protocol. A computer physically located on the telescope handles the acquisition and tracking of stars. We avoid the need for real-time programming in this application by periodically latching the positions of the axes in a commercial motion controller and the time in a GPS receiver. A second (spectrograph) computer sets up the spectrograph and runs its CCD, a third (roof) computer controls the roll-off roof and front flap of the telescope enclosure, and the fourth (executive) computer makes decisions about which stars to observe and when to close the observatory for bad weather. The only human intervention in the telescope's operation involves changing the observing program, copying data back to TSU, and running quality-control checks on the data. It has been running reliably in this completely automatic, unattended mode for more than a year with all day-to-day adminsitration carried out over the Internet. To support automatic operation, we have written a number of useful tools to predict and analyze what the telescope does. These include a simulator that predicts roughly how the telescope will operate on a given night, a quality-control program to parse logfiles from the telescope and identify problems, and a rescheduling program that calculates new priorities to keep the frequency of observation for the various stars roughly as desired. We have also set up a database to keep track of the tens of thousands of spectra we expect to get each year.

Optimal algorithm for automatic detection of microaneurysms based on receiver operating characteristic curve

NASA Astrophysics Data System (ADS)

Xu, Lili; Luo, Shuqian

2010-11-01

Microaneurysms (MAs) are the first manifestations of the diabetic retinopathy (DR) as well as an indicator for its progression. Their automatic detection plays a key role for both mass screening and monitoring and is therefore in the core of any system for computer-assisted diagnosis of DR. The algorithm basically comprises the following stages: candidate detection aiming at extracting the patterns possibly corresponding to MAs based on mathematical morphological black top hat, feature extraction to characterize these candidates, and classification based on support vector machine (SVM), to validate MAs. Feature vector and kernel function of SVM selection is very important to the algorithm. We use the receiver operating characteristic (ROC) curve to evaluate the distinguishing performance of different feature vectors and different kernel functions of SVM. The ROC analysis indicates the quadratic polynomial SVM with a combination of features as the input shows the best discriminating performance.

Optimal algorithm for automatic detection of microaneurysms based on receiver operating characteristic curve.

PubMed

Xu, Lili; Luo, Shuqian

2010-01-01

Microaneurysms (MAs) are the first manifestations of the diabetic retinopathy (DR) as well as an indicator for its progression. Their automatic detection plays a key role for both mass screening and monitoring and is therefore in the core of any system for computer-assisted diagnosis of DR. The algorithm basically comprises the following stages: candidate detection aiming at extracting the patterns possibly corresponding to MAs based on mathematical morphological black top hat, feature extraction to characterize these candidates, and classification based on support vector machine (SVM), to validate MAs. Feature vector and kernel function of SVM selection is very important to the algorithm. We use the receiver operating characteristic (ROC) curve to evaluate the distinguishing performance of different feature vectors and different kernel functions of SVM. The ROC analysis indicates the quadratic polynomial SVM with a combination of features as the input shows the best discriminating performance.

Tools Automate Spacecraft Testing, Operation

NASA Technical Reports Server (NTRS)

2010-01-01

"NASA began the Small Explorer (SMEX) program to develop spacecraft to advance astrophysics and space physics. As one of the entities supporting software development at Goddard Space Flight Center, the Hammers Company Inc. (tHC Inc.), of Greenbelt, Maryland, developed the Integrated Test and Operations System to support SMEX. Later, the company received additional Small Business Innovation Research (SBIR) funding from Goddard for a tool to facilitate the development of flight software called VirtualSat. NASA uses the tools to support 15 satellites, and the aerospace industry is using them to develop science instruments, spacecraft computer systems, and navigation and control software."

Time synchronization via lunar radar.

NASA Technical Reports Server (NTRS)

Higa, W. H.

1972-01-01

The advent of round-trip radar measurements has permitted the determination of the ranges to the nearby planets with greater precision than was previously possible. When the distances to the planets are known with high precision, the propagation delay for electromagnetic waves reflected by the planets may be calculated and used to synchronize remotely located clocks. Details basic to the operation of a lunar radar indicate a capability for clock synchronization to plus or minus 20 microsec. One of the design goals for this system was to achieve a simple semiautomatic receiver for remotely located tracking stations. The lunar radar system is in operational use for deep space tracking at Jet Propulsion Laboratory and synchronizes five world-wide tracking stations with a master clock at Goldstone, Calif. Computers are programmed to correct the Goldstone transmissions for transit time delay and Doppler shifts so as to be received on time at the tracking stations; this dictates that only one station can be synchronized at a given time period and that the moon must be simultaneously visible to both the transmitter and receiver for a minimum time of 10 min.-

Satellite data-relay activities in Arizona

USGS Publications Warehouse

Boner, F.C.; Blee, J.W.; Shope, W.G.

1985-01-01

The U.S. Geological Survey (USGS) Arizona District collects data from automated streamflow stations for a wide variety of uses. Data from these stations are provided to Federal, State, and local agencies that have a responsibility to issue flood warnings; to generate forecasts of water availability; to monitor flow to insure compliance with treaties and other legal mandates; and to manage reservoirs for hydropower, flood abatement, and municipal and irrigation water supply. In the mid-1970's, the escalation of data collection costs and a need for more timely data led the Arizona District to examine alternatives for remote data acquisition. On the basis of successful data communications experiments with NASA 's Landsat satellite, an operational system for satellite-data relay was developed in 1976 using the National Oceanic and Atmospheric Administrations 's (NOAA) Geostationary Operational Environmental Satellite (GOES). A total of 62 data collection platforms (DCP's) was operated in 1983. Satellite telemetry operations are controlled at the remote data-collection stations by small battery-operated data collection platforms. The DCP 's periodically collect data from the sensors, store the data in computer memory, and at preset times transmit the data to the GOES satellite. The satellite retransmits the data to Earth where a ground-receive station transmits or transfers the data by land communications to the USGS computer in Reston, Virginia, for processing. The satellite relay transfers the data from sensor to computer in minutes; therefore, the data are available to users on a near real-time basis. (Author 's abstract)

Parametric optimization of optical signal detectors employing the direct photodetection scheme

NASA Astrophysics Data System (ADS)

Kirakosiants, V. E.; Loginov, V. A.

1984-08-01

The problem of optimization of the optical signal detection scheme parameters is addressed using the concept of a receiver with direct photodetection. An expression is derived which accurately approximates the field of view (FOV) values obtained by a direct computer minimization of the probability of missing a signal; optimum values of the receiver FOV were found for different atmospheric conditions characterized by the number of coherence spots and the intensity fluctuations of a plane wave. It is further pointed out that the criterion presented can be possibly used for parametric optimization of detectors operating in accordance with the Neumann-Pearson criterion.

Electron beam diagnostic system using computed tomography and an annular sensor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elmer, John W.; Teruya, Alan T.

2015-08-11

A system for analyzing an electron beam including a circular electron beam diagnostic sensor adapted to receive the electron beam, the circular electron beam diagnostic sensor having a central axis; an annular sensor structure operatively connected to the circular electron beam diagnostic sensor, wherein the sensor structure receives the electron beam; a system for sweeping the electron beam radially outward from the central axis of the circular electron beam diagnostic sensor to the annular sensor structure wherein the electron beam is intercepted by the annular sensor structure; and a device for measuring the electron beam that is intercepted by themore » annular sensor structure.« less

Electron beam diagnostic system using computed tomography and an annular sensor

DOEpatents

Elmer, John W.; Teruya, Alan T.

2014-07-29

A system for analyzing an electron beam including a circular electron beam diagnostic sensor adapted to receive the electron beam, the circular electron beam diagnostic sensor having a central axis; an annular sensor structure operatively connected to the circular electron beam diagnostic sensor, wherein the sensor structure receives the electron beam; a system for sweeping the electron beam radially outward from the central axis of the circular electron beam diagnostic sensor to the annular sensor structure wherein the electron beam is intercepted by the annular sensor structure; and a device for measuring the electron beam that is intercepted by the annular sensor structure.

Administering truncated receive functions in a parallel messaging interface

DOEpatents

Archer, Charles J; Blocksome, Michael A; Ratterman, Joseph D; Smith, Brian E

2014-12-09

Administering truncated receive functions in a parallel messaging interface (`PMI`) of a parallel computer comprising a plurality of compute nodes coupled for data communications through the PMI and through a data communications network, including: sending, through the PMI on a source compute node, a quantity of data from the source compute node to a destination compute node; specifying, by an application on the destination compute node, a portion of the quantity of data to be received by the application on the destination compute node and a portion of the quantity of data to be discarded; receiving, by the PMI on the destination compute node, all of the quantity of data; providing, by the PMI on the destination compute node to the application on the destination compute node, only the portion of the quantity of data to be received by the application; and discarding, by the PMI on the destination compute node, the portion of the quantity of data to be discarded.

Thermal buffering of receivers for parabolic dish solar thermal power plants

NASA Technical Reports Server (NTRS)

Manvi, R.; Fujita, T.; Gajanana, B. C.; Marcus, C. J.

1980-01-01

A parabolic dish solar thermal power plant comprises a field of parabolic dish power modules where each module is composed of a two-axis tracking parabolic dish concentrator which reflects sunlight (insolation) into the aperture of a cavity receiver at the focal point of the dish. The heat generated by the solar flux entering the receiver is removed by a heat transfer fluid. In the dish power module, this heat is used to drive a small heat engine/generator assembly which is directly connected to the cavity receiver at the focal point. A computer analysis is performed to assess the thermal buffering characteristics of receivers containing sensible and latent heat thermal energy storage. Parametric variations of the thermal inertia of the integrated receiver-buffer storage systems coupled with different fluid flow rate control strategies are carried out to delineate the effect of buffer storage, the transient response of the receiver-storage systems and corresponding fluid outlet temperature. It is concluded that addition of phase change buffer storage will substantially improve system operational characteristics during periods of rapidly fluctuating insolation due to cloud passage.

Radar cross calibration investigation TAMU radar polarimeter calibration measurements

NASA Technical Reports Server (NTRS)

Blanchard, A. J.; Newton, R. W.; Bong, S.; Kronke, C.; Warren, G. L.; Carey, D.

1982-01-01

A short pulse, 20 MHz bandwidth, three frequency radar polarimeter system (RPS) operates at center frequencies of 10.003 GHz, 4.75 GHz, and 1.6 GHz and utilizes dual polarized transmit and receive antennas for each frequency. The basic lay-out of the RPS is different from other truck mounted systems in that it uses a pulse compression IF section common to all three RF heads. Separate transmit and receive antennas are used to improve the cross-polarization isolation at each particular frequency. The receive is a digitally controlled gain modulated subsystem and is interfaced directly with a microprocesser computer for control and data manipulation. Antenna focusing distance, focusing each antenna pair, rf head stability, and polarization characteristics of RPS antennas are discussed. Platform and data acquisition procedures are described.

Logic Gate Operation by DNA Translocation through Biological Nanopores.

PubMed

Yasuga, Hiroki; Kawano, Ryuji; Takinoue, Masahiro; Tsuji, Yutaro; Osaki, Toshihisa; Kamiya, Koki; Miki, Norihisa; Takeuchi, Shoji

2016-01-01

Logical operations using biological molecules, such as DNA computing or programmable diagnosis using DNA, have recently received attention. Challenges remain with respect to the development of such systems, including label-free output detection and the rapidity of operation. Here, we propose integration of biological nanopores with DNA molecules for development of a logical operating system. We configured outputs "1" and "0" as single-stranded DNA (ssDNA) that is or is not translocated through a nanopore; unlabeled DNA was detected electrically. A negative-AND (NAND) operation was successfully conducted within approximately 10 min, which is rapid compared with previous studies using unlabeled DNA. In addition, this operation was executed in a four-droplet network. DNA molecules and associated information were transferred among droplets via biological nanopores. This system would facilitate linking of molecules and electronic interfaces. Thus, it could be applied to molecular robotics, genetic engineering, and even medical diagnosis and treatment.

Logic Gate Operation by DNA Translocation through Biological Nanopores

PubMed Central

Takinoue, Masahiro; Tsuji, Yutaro; Osaki, Toshihisa; Kamiya, Koki; Miki, Norihisa; Takeuchi, Shoji

2016-01-01

Logical operations using biological molecules, such as DNA computing or programmable diagnosis using DNA, have recently received attention. Challenges remain with respect to the development of such systems, including label-free output detection and the rapidity of operation. Here, we propose integration of biological nanopores with DNA molecules for development of a logical operating system. We configured outputs “1” and “0” as single-stranded DNA (ssDNA) that is or is not translocated through a nanopore; unlabeled DNA was detected electrically. A negative-AND (NAND) operation was successfully conducted within approximately 10 min, which is rapid compared with previous studies using unlabeled DNA. In addition, this operation was executed in a four-droplet network. DNA molecules and associated information were transferred among droplets via biological nanopores. This system would facilitate linking of molecules and electronic interfaces. Thus, it could be applied to molecular robotics, genetic engineering, and even medical diagnosis and treatment. PMID:26890568

Intuitive Space Weather Displays to Improve Space Situational Awareness (SSA)

DTIC Science & Technology

2011-09-01

parsimonious offering. After engaging several mathematicians and space physicists to devise valid computational formulas for aggregating the four hazard... PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Aptima, Inc.,12 Gill Street Ste 200,Woburn,MA... physicists , the operational users find little use in receiving particle fluxes or magnetometer readings collected by the scientific community. Fortunately

CMOS Camera Array With Onboard Memory

NASA Technical Reports Server (NTRS)

Gat, Nahum

2009-01-01

A compact CMOS (complementary metal oxide semiconductor) camera system has been developed with high resolution (1.3 Megapixels), a USB (universal serial bus) 2.0 interface, and an onboard memory. Exposure times, and other operating parameters, are sent from a control PC via the USB port. Data from the camera can be received via the USB port and the interface allows for simple control and data capture through a laptop computer.

The radiometer transfer function for the AAFE composite two-frequency radiometer scatterometer. M.S. Thesis - Pennsylvania Univ.

NASA Technical Reports Server (NTRS)

Moore, J. H.

1973-01-01

A model was developed for the switching radiometer utilizing a continuous method of calibration. Sources of system degradation were identified and include losses and voltage standing wave ratios in front of the receiver input. After computing the three modes of operation, expressions were developed for the normalized radiometer output, the minimum detectable signal (normalized RMS temperature fluctuation), sensitivity, and accuracy correction factors).

Design of a receiver operating characteristic (ROC) study of 10:1 lossy image compression

NASA Astrophysics Data System (ADS)

Collins, Cary A.; Lane, David; Frank, Mark S.; Hardy, Michael E.; Haynor, David R.; Smith, Donald V.; Parker, James E.; Bender, Gregory N.; Kim, Yongmin

1994-04-01

The digital archiving system at Madigan Army Medical Center (MAMC) uses a 10:1 lossy data compression algorithm for most forms of computed radiography. A systematic study on the potential effect of lossy image compression on patient care has been initiated with a series of studies focused on specific diagnostic tasks. The studies are based upon the receiver operating characteristic (ROC) method of analysis for diagnostic systems. The null hypothesis is that observer performance with approximately 10:1 compressed and decompressed images is not different from using original, uncompressed images for detecting subtle pathologic findings seen on computed radiographs of bone, chest, or abdomen, when viewed on a high-resolution monitor. Our design involves collecting cases from eight pathologic categories. Truth is determined by committee using confirmatory studies performed during routine clinical practice whenever possible. Software has been developed to aid in case collection and to allow reading of the cases for the study using stand-alone Siemens Litebox workstations. Data analysis uses two methods, ROC analysis and free-response ROC (FROC) methods. This study will be one of the largest ROC/FROC studies of its kind and could benefit clinical radiology practice using PACS technology. The study design and results from a pilot FROC study are presented.

Planned LMSS propagation experiment using ACTS: Preliminary antenna pointing results during mobile operations

NASA Technical Reports Server (NTRS)

Rowland, John R.; Goldhirsh, Julius; Vogel, Wolfhard J.; Torrence, Geoffrey W.

1991-01-01

An overview and a status description of the planned LMSS mobile K band experiment with ACTS is presented. As a precursor to the ACTS mobile measurements at 20.185 GHz, measurements at 19.77 GHz employing the Olympus satellite were originally planned. However, because of the demise of Olympus in June of 1991, the efforts described here are focused towards the ACTS measurements. In particular, we describe the design and testing results of a gyro controlled mobile-antenna pointing system. Preliminary pointing measurements during mobile operations indicate that the present system is suitable for measurements employing a 15 cm aperture (beamwidth at approximately 7 deg) receiving antenna operating with ACTS in the high gain transponder mode. This should enable measurements with pattern losses smaller than plus or minus 1 dB over more than 95 percent of the driving distance. Measurements with the present mount system employing a 60 cm aperture (beamwidth at approximately 1.7 deg) results in pattern losses smaller than plus or minus 3 dB for 70 percent of the driving distance. Acceptable propagation measurements may still be made with this system by employing developed software to flag out bad data points due to extreme pointing errors. The receiver system including associated computer control software has been designed and assembled. Plans are underway to integrate the antenna mount with the receiver on the University of Texas mobile receiving van and repeat the pointing tests on highways employing a recently designed radome system.

[Analysis and evaluation of the visual effort in remote-control public traffic operators working with computer-based equipments].

PubMed

Gullà, F; Zambelli, P; Bergamaschi, A; Piccoli, B

2007-01-01

The aim of this study is the objective evaluation of the visual effort in 6 public traffic controllers (4 male, 2 female, mean age 29,6), by means of electronic equipment. The electronic equipment quantify the observation distance and the observation time for each controller's occupational visual field. The quantification of these parameters is obtained by the emission of ultrasound at 40 KHz from an emission sensor (placed by the VDT screen) and the ultrasound reception by means of a receiving sensor (placed on the operator's head). The travelling time of the ultrasound (US), as the air speed is known and costant (about 340 m/s), it is used to calculate the distance between the emitting and the receiving sensor. The results show that the visual acuity required is of average level, while accommodation's and convergence's effort vary from average to intense (depending on the visual characteristics of the operator considered), ranging from 26,41 and 43,92% of accommodation and convergence available in each operator. The time actually spent in "near observation within the c.v.p." (Tscr) was maintained in a range from 2h 54' and 4h 05'.

[INVITED] Computational intelligence for smart laser materials processing

NASA Astrophysics Data System (ADS)

Casalino, Giuseppe

2018-03-01

Computational intelligence (CI) involves using a computer algorithm to capture hidden knowledge from data and to use them for training ;intelligent machine; to make complex decisions without human intervention. As simulation is becoming more prevalent from design and planning to manufacturing and operations, laser material processing can also benefit from computer generating knowledge through soft computing. This work is a review of the state-of-the-art on the methodology and applications of CI in laser materials processing (LMP), which is nowadays receiving increasing interest from world class manufacturers and 4.0 industry. The focus is on the methods that have been proven effective and robust in solving several problems in welding, cutting, drilling, surface treating and additive manufacturing using the laser beam. After a basic description of the most common computational intelligences employed in manufacturing, four sections, namely, laser joining, machining, surface, and additive covered the most recent applications in the already extensive literature regarding the CI in LMP. Eventually, emerging trends and future challenges were identified and discussed.

Collectively loading programs in a multiple program multiple data environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aho, Michael E.; Attinella, John E.; Gooding, Thomas M.

Techniques are disclosed for loading programs efficiently in a parallel computing system. In one embodiment, nodes of the parallel computing system receive a load description file which indicates, for each program of a multiple program multiple data (MPMD) job, nodes which are to load the program. The nodes determine, using collective operations, a total number of programs to load and a number of programs to load in parallel. The nodes further generate a class route for each program to be loaded in parallel, where the class route generated for a particular program includes only those nodes on which the programmore » needs to be loaded. For each class route, a node is selected using a collective operation to be a load leader which accesses a file system to load the program associated with a class route and broadcasts the program via the class route to other nodes which require the program.« less

Automated apparatus for producing gradient gels

DOEpatents

Anderson, N.L.

1983-11-10

Apparatus for producing a gradient gel which serves as a standard medium for a two-dimensional analysis of proteins, the gel having a density gradient along its height formed by a variation in gel composition, with the apparatus including first and second pumping means each including a plurality of pumps on a common shaft and driven by a stepping motor capable of providing small incremental changes in pump outputs for the gel ingredients, the motors being controlled, by digital signals from a digital computer, a hollow form or cassette for receiving the gel composition, means for transferring the gel composition including a filler tube extending near the bottom of the cassette, adjustable horizontal and vertical arms for automatically removing and relocating the filler tube in the next cassette, and a digital computer programmed to automatically control the stepping motors, arm movements, and associated sensing operations involving the filling operation.

Automated apparatus for producing gradient gels

DOEpatents

Anderson, Norman L.

1986-01-01

Apparatus for producing a gradient gel which serves as a standard medium for a two-dimensional analysis of proteins, the gel having a density gradient along its height formed by a variation in gel composition, with the apparatus including first and second pumping means each including a plurality of pumps on a common shaft and driven by a stepping motor capable of providing small incremental changes in pump outputs for the gel ingredients, the motors being controlled, by digital signals from a digital computer, a hollow form or cassette for receiving the gel composition, means for transferring the gel composition including a filler tube extending near the bottom of the cassette, adjustable horizontal and vertical arms for automatically removing and relocating the filler tube in the next cassette, and a digital computer programmed to automatically control the stepping motors, arm movements, and associated sensing operations involving the filling operation.

A digital-receiver for the MurchisonWidefield Array

NASA Astrophysics Data System (ADS)

Prabu, Thiagaraj; Srivani, K. S.; Roshi, D. Anish; Kamini, P. A.; Madhavi, S.; Emrich, David; Crosse, Brian; Williams, Andrew J.; Waterson, Mark; Deshpande, Avinash A.; Shankar, N. Udaya; Subrahmanyan, Ravi; Briggs, Frank H.; Goeke, Robert F.; Tingay, Steven J.; Johnston-Hollitt, Melanie; R, Gopalakrishna M.; Morgan, Edward H.; Pathikulangara, Joseph; Bunton, John D.; Hampson, Grant; Williams, Christopher; Ord, Stephen M.; Wayth, Randall B.; Kumar, Deepak; Morales, Miguel F.; deSouza, Ludi; Kratzenberg, Eric; Pallot, D.; McWhirter, Russell; Hazelton, Bryna J.; Arcus, Wayne; Barnes, David G.; Bernardi, Gianni; Booler, T.; Bowman, Judd D.; Cappallo, Roger J.; Corey, Brian E.; Greenhill, Lincoln J.; Herne, David; Hewitt, Jacqueline N.; Kaplan, David L.; Kasper, Justin C.; Kincaid, Barton B.; Koenig, Ronald; Lonsdale, Colin J.; Lynch, Mervyn J.; Mitchell, Daniel A.; Oberoi, Divya; Remillard, Ronald A.; Rogers, Alan E.; Salah, Joseph E.; Sault, Robert J.; Stevens, Jamie B.; Tremblay, S.; Webster, Rachel L.; Whitney, Alan R.; Wyithe, Stuart B.

2015-03-01

An FPGA-based digital-receiver has been developed for a low-frequency imaging radio interferometer, the Murchison Widefield Array (MWA). The MWA, located at the Murchison Radio-astronomy Observatory (MRO) in Western Australia, consists of 128 dual-polarized aperture-array elements (tiles) operating between 80 and 300 MHz, with a total processed bandwidth of 30.72 MHz for each polarization. Radio-frequency signals from the tiles are amplified and band limited using analog signal conditioning units; sampled and channelized by digital-receivers. The signals from eight tiles are processed by a single digital-receiver, thus requiring 16 digital-receivers for the MWA. The main function of the digital-receivers is to digitize the broad-band signals from each tile, channelize them to form the sky-band, and transport it through optical fibers to a centrally located correlator for further processing. The digital-receiver firmware also implements functions to measure the signal power, perform power equalization across the band, detect interference-like events, and invoke diagnostic modes. The digital-receiver is controlled by high-level programs running on a single-board-computer. This paper presents the digital-receiver design, implementation, current status, and plans for future enhancements.

Association of pre-operative medication use with post-operative delirium in surgical oncology patients receiving comprehensive geriatric assessment.

PubMed

Jeong, Young Mi; Lee, Eunsook; Kim, Kwang-Il; Chung, Jee Eun; In Park, Hae; Lee, Byung Koo; Gwak, Hye Sun

2016-07-07

Older patients undergoing surgery tend to have a higher frequency of delirium. Delirium is strongly associated with poor surgical outcomes. This study evaluated the association between pre-operative medication use and post-operative delirium (POD) in surgical oncology patients receiving comprehensive geriatric assessment (CGA). A total of 475 patients who were scheduled for cancer surgery and received CGA from January 2014 to June 2015 were included. Pre-operative medication review through CGA was conducted on polypharmacy (≥5 medications), delirium-inducing medications (DIMs), fall-inducing medications (FIMs), and potentially inappropriate medications (PIMs). POD was confirmed by psychiatric consultation, and DSM-V criteria were used for diagnosing delirium. The model fit of the prediction model was assessed by computing the Hosmer-Lemeshow goodness-of-fit test. Effect size was measured using the Nagelkerke R(2). Discrimination of the model was assessed by an analysis of the area under receiver operating curve (AUROC). Two models were constructed for multivariate analysis based on univariate analysis; model I included dementia and DIM in addition to age and sex, and model II included PIM instead of DIM of model I. Every one year increase of age increased the risk of POD by about 1.1-fold. DIM was a significant factor for POD after adjusting for confounders (AOR 12.78, 95 % CI 2.83-57.74). PIM was also a significant factor for POD (AOR 5.53, 95 % CI 2.03-15.05). The Hosmer-Lemeshow test results revealed good fits for both models (χ(2) = 3.842, p = 0.871 for model I and χ(2) = 8.130, p = 0.421 for model II). The Nagelkerke R(2) effect size and AUROC for model I was 0.215 and 0.833, respectively. Model II had the Nagelkerke R(2)effect size of 0.174 and AUROC of 0.819. These results suggest that pharmacists' comprehensive review for pre-operative medication use is critical for the post-operative outcomes like delirium in older patients.

Olympus beacon receiver

NASA Technical Reports Server (NTRS)

Ostergaard, Jens

1988-01-01

A medium-size Beacon Receiving System for reception and processing of the B1 (20 GHz) and B2 (30 GHz) beacons from Olympus has been developed. Integration of B1 and B2 receiving equipment into one system using one antenna and a common computer for control and data processing provides the advantages of a compact configuration and synchronization of the two receiver chains. Range for co-polar signal attenuation meaurement is about 30 dB for both beacons, increasing to 40 dB for B2 if the receivers are synchronized to B1. The accuracy is better than 0.5 dB. Cross-polarization discriminations of the order of 10 to 30 dB may be determined with an accuracy of 1 to 2 dB. A number of radiometers for complementary measurements of atmospheric attenuation of 13 to 30 GHz has also been constructed. A small multi-frequency system for operation around 22 GHz and 31 GHz is presently under development.

GPS application to mapping, charting and geodesy

NASA Technical Reports Server (NTRS)

Senus, W. J.; Hill, R. W.

1981-01-01

GPSPAC, a receiver being developed for space applications by the Defense Mapping Agency and NASA, will use signals from GPS constellations to generate real-time values of host vehicle position and velocity. The GPSPAC has an L-band antenna and preamp capable of receiving the 1575 MHz and 1227 MHz spread spectrum signals; its stable oscillator at 5.115 MHz provides the basic frequency reference, resulting in a long term drift of less than one part in 10 to the -10th day. The GPSPAC performs many functions on board the spacecraft which were previously relegated to large-scale ground-based computer/receiver systems. A positional accuracy of better than 8 can be achieved for those periods when four or more NAVSTAR satellites are visible to the host satellite. The GPS geodetic receiver development, which will provide prototype receivers for utilization in terrestrial surveying operations, has the potential to significantly enhance the accuracy of point geodetic surveys over the current user hardware capability.

Development of a computed tomography-based scoring system for necrotizing soft-tissue infections.

PubMed

McGillicuddy, Edward A; Lischuk, Andrew W; Schuster, Kevin M; Kaplan, Lewis J; Maung, Adrian; Lui, Felix Y; Bokhari, S A Jamal; Davis, Kimberly A

2011-04-01

Necrotizing soft-tissue infections (NSTIs) are associated with significant morbidity and mortality, but a definitive nonsurgical diagnostic test remains elusive. Despite the widespread use of computed tomography (CT) as a diagnostic adjunct, there is little data that definitively correlate CT findings with the presence of NSTI. Our goal was the development of a CT-based scoring system to discriminate non-NSTI from NSTI. Patients older than 17 years undergoing CT for evaluation of soft-tissue infection at a tertiary care medical center over a 10-year period (2000-2009) were included. Abstracted data included comorbidities and social history, physical examination, laboratory findings, and operative and pathologic findings. NSTI was defined as soft-tissue necrosis in the dictated operative note or the accompanying pathology report. CT scans were reviewed by a radiologist blinded to clinical and laboratory data. A scoring system was developed and the area under the receiver operating characteristic curve was calculated. During the study period, 305 patients underwent CT scanning (57% men; mean age, 47.4 years). Forty-four patients (14.4%) evaluated had an NSTI. A scoring system was retrospectively developed (table). A score >6 points was 86.3% sensitive and 91.5% specific for the diagnosis of NSTI (positive predictive value, 63.3%; negative predictive value, 85.5%). The area under the receiver operating characteristic curve was 0.928 (95% confidence interval, 0.893-0.964). The mean score of the non-NSTI group was 2.74. We have developed a CT scoring system that is both sensitive and specific for the diagnosis of NSTIs. This system may allow clinicians to more accurately diagnose NSTIs. Prospective validation of this scoring system is planned.

A Compact High Frequency Doppler Radio Scatterometer for Coastal Oceanography

NASA Astrophysics Data System (ADS)

Flament, P. J.; Harris, D.; Flament, M.; Fernandez, I. Q.; Hlivak, R.; Flores-vidal, X.; Marié, L.

2016-12-01

A low-power High Frequency Doppler Radar has been designed for large series production. The use of commercial-off-the-shelf components is maximized to minimize overall cost. Power consumption is reduced to 130W in full duty and 20W in stand-by under 20-36 V-DC, thus enabling solar/wind and/or fuel cell operation by default. For 8 channels, commercial components and sub-assemblies cost less than k20 excluding coaxial antenna cables, and less than four man-weeks of technician suffice for integration, testing and calibration, suggesting a final cost of about k36, based on production batches of 25 units. The instrument is integrated into passively-cooled 90x60x20 cm3 field-deployable enclosures, combining signal generation, transmitter, received, A/D converter and computer, alleviating the need for additional protection such as a container or building. It uses frequency-ramped continuous wave signals, and phased-array transmissions to decouple the direct path to the receivers. Five sub-assemblies are controlled by a Linux embedded computer: (i) direct digital synthesis of transmit and orthogonal local oscillator signals, derived from a low phase noise oven-controlled crystal; (ii) distributed power amplifiers totaling 5 W, integrated into λ/8 passive transmit antenna monopoles; (iii) λ/12 compact active receive antenna monopoles with embedded out-of-band rejection filters; (iv) analog receivers based on complex demodulation by double-balanced mixers, translating the HF spectrum to the audio band; (v) 24-bit analog-to-digital sigma-delta conversion at 12 kHz with 512x oversampling, followed by decimation to a final sampling frequency of 750 Hz. Except for the HF interference rejection filters, the electronics can operate between 3 and 50 MHz with no modification. At 13.5 MHz, 5 W transmit power, 15 min integration time, the high signal-to-noise ratio permits a typical range of 120 km for currents measurements with 8-antenna beam-forming. The University of Hawaii HFR has been used since 2013 with 100% reliability, and has been deployed operationally at 7 sites in Hawaii, 4 sites in Baja California, and 1 site in France.

CIP Training Manual: Collaborative Information Portal Advance Training Information for Field Test Participants

NASA Technical Reports Server (NTRS)

Schreiner, John; Clancy, Daniel (Technical Monitor)

2002-01-01

The Collaborative Information Portal (CIP) is a web-based information management and retrieval system. Its purpose is to provide users at MER (Mars Exploration Rover) mission operations with easy access to a broad range of mission data and products and contextual information such as the current operations schedule. The CIP web-server provides this content in a user customizable web-portal environment. Since CIP is still under development, only a subset of the full feature set will be available for the EDO field test. The CIP web-portal will be accessed through a standard web browser. CIP is intended to be intuitive and simple to use, however, at the training session, users will receive a one to two page reference guide, which should aid them in using CIP. Users must provide their own computers for accessing CIP during the field test. These computers should be configured with Java 1.3 and a Java 2 enabled browser. Macintosh computers should be running OS 10.1.3 or later. Classic Mac OS (OS 9) is not supported. For more information please read section 7.3 in the FIASCO Rover Science Operations Test Mission Plan. Several screen shots of the Beta Release of CIP are shown on the following pages.

Usability of a Low-Cost Head Tracking Computer Access Method following Stroke.

PubMed

Mah, Jasmine; Jutai, Jeffrey W; Finestone, Hillel; Mckee, Hilary; Carter, Melanie

2015-01-01

Assistive technology devices for computer access can facilitate social reintegration and promote independence for people who have had a stroke. This work describes the exploration of the usefulness and acceptability of a new computer access device called the Nouse™ (Nose-as-mouse). The device uses standard webcam and video recognition algorithms to map the movement of the user's nose to a computer cursor, thereby allowing hands-free computer operation. Ten participants receiving in- or outpatient stroke rehabilitation completed a series of standardized and everyday computer tasks using the Nouse™ and then completed a device usability questionnaire. Task completion rates were high (90%) for computer activities only in the absence of time constraints. Most of the participants were satisfied with ease of use (70%) and liked using the Nouse™ (60%), indicating they could resume most of their usual computer activities apart from word-processing using the device. The findings suggest that hands-free computer access devices like the Nouse™ may be an option for people who experience upper motor impairment caused by stroke and are highly motivated to resume personal computing. More research is necessary to further evaluate the effectiveness of this technology, especially in relation to other computer access assistive technology devices.

Preconsultation use of analgesics on adults presenting to the emergency department with acute appendicitis

PubMed Central

Chong, C; Wang, T; Chen, C; Ma, H; Chang, H

2004-01-01

Objective: 279 cases of appendicitis were reviewed and compared for the difference between those patients who received pain medication before consulting a surgeon and those who were not treated with analgesics. Methods: All patients aged 15 years and older who underwent appendicectomy for appendicitis between 1 July 2001 and 30 June 2002 were divided into group 1 (those who received preconsultaion use of analgesics) and group 2 (those who were not treated with analgesics). The following measures were compared: age, sex, symptom duration, initial vital signs, white blood cell counts, frequency of imaging studies, time to operative intervention, and operative findings. Continuous and categorical variables were analysed using t and χ2 tests, respectively. Results: A total of 279 patients were included for analysis. Patient details (age, sex, symptom duration) of the two study groups were similar. There was no statistically significant difference between group 1 and group 2 with respect to vital signs (systolic blood pressure, pulse rate, respiratory rate, body temperature), white blood cell counts, and frequency of imaging studies (ultrasound, computed tomography). There was no significant difference in the rate of perforated appendicitis between the two study groups although a shorter median time to operative intervention has been found in the group who received analegesia. Conclusion: The preconsultation use of analgesics in ED patients with a final diagnosis of appendicitis is not associated with a longer delay to operative intervention and is not associated with an increased rate of perforated appendicitis. PMID:14734373

Establishing a group of endpoints in a parallel computer

DOEpatents

Archer, Charles J.; Blocksome, Michael A.; Ratterman, Joseph D.; Smith, Brian E.; Xue, Hanhong

2016-02-02

A parallel computer executes a number of tasks, each task includes a number of endpoints and the endpoints are configured to support collective operations. In such a parallel computer, establishing a group of endpoints receiving a user specification of a set of endpoints included in a global collection of endpoints, where the user specification defines the set in accordance with a predefined virtual representation of the endpoints, the predefined virtual representation is a data structure setting forth an organization of tasks and endpoints included in the global collection of endpoints and the user specification defines the set of endpoints without a user specification of a particular endpoint; and defining a group of endpoints in dependence upon the predefined virtual representation of the endpoints and the user specification.

A software control system for the ACTS high-burst-rate link evaluation terminal

NASA Technical Reports Server (NTRS)

Reinhart, Richard C.; Daugherty, Elaine S.

1991-01-01

Control and performance monitoring of NASA's High Burst Rate Link Evaluation Terminal (HBR-LET) is accomplished by using several software control modules. Different software modules are responsible for controlling remote radio frequency (RF) instrumentation, supporting communication between a host and a remote computer, controlling the output power of the Link Evaluation Terminal and data display. Remote commanding of microwave RF instrumentation and the LET digital ground terminal allows computer control of various experiments, including bit error rate measurements. Computer communication allows system operators to transmit and receive from the Advanced Communications Technology Satellite (ACTS). Finally, the output power control software dynamically controls the uplink output power of the terminal to compensate for signal loss due to rain fade. Included is a discussion of each software module and its applications.

Mass screening of multiple abdominal solid organs using mobile helical computed tomography scanner--a preliminary report.

PubMed

Ishikawa, Susumu; Aoki, Jun; Ohwada, Susumu; Takahashi, Toru; Morishita, Yasuo; Ueda, Keisuke

2007-04-01

The possibility of a new screening procedure for multiple abdominal solid organs using a mobile helical computed tomography (CT) scanner was evaluated. A total of 4,543 residents, who were 40 years of age or older, received CT scanning without contrast medium. The mean age of participants was 64 years including 2,022 males and 2,521 females. A total of 2,105 abnormal findings were uniquely detected in 1,594 participants. Liver and kidney diseases including ureter occupied around 30% of total abnormal findings, respectively. Besides frequent cystic or calcified lesions, solid tumours were suspected in 56 lesions, which received further examination by specialized physicians. Five (9%) of them were confirmed as being malignant tumours including pancreatic cancer in two patients, and liver, lung and ovary cancers in one patient each, respectively. All five patients with each malignant lesion received curative operations. Small-sized abdominal aortic aneurysms and heart valve diseases were uniquely found in 22 and two patients, respectively. Qualitative diagnoses of solid tumours were difficult using CT findings without contrast medium. CT screening procedures require further investigation in aspect of the selection of examinees, CT scanning procedure, sensitivity and specificity, and cost-effectiveness.

Portable appliance security apparatus

NASA Technical Reports Server (NTRS)

Kerley, J. J. (Inventor)

1981-01-01

An apparatus for securing a small computer, or other portable appliance, against theft is described. It is comprised of a case having an open back through which the computer is installed or removed. Guide members in the form of slots are formed in a rear portion of opposite walls of the case for receiving a back plate to cover the opening and thereby secure the computer within the case. An opening formed in the top wall of the case exposes the keyboard and display of the computer. The back plate is locked in the closed position by a key-operated plug type lock. The lock is attached to one end of a hold down cable, the opposite end thereof being secured to a desk top or other stationary object. Thus, the lock simultaneously secures the back plate to the case and retains the case to the stationary object.

Radiation Exposure of Interventional Radiologists During Computed Tomography Fluoroscopy-Guided Renal Cryoablation and Lung Radiofrequency Ablation: Direct Measurement in a Clinical Setting.

PubMed

Matsui, Yusuke; Hiraki, Takao; Gobara, Hideo; Iguchi, Toshihiro; Fujiwara, Hiroyasu; Kawabata, Takahiro; Yamauchi, Takatsugu; Yamaguchi, Takuya; Kanazawa, Susumu

2016-06-01

Computed tomography (CT) fluoroscopy-guided renal cryoablation and lung radiofrequency ablation (RFA) have received increasing attention as promising cancer therapies. Although radiation exposure of interventional radiologists during these procedures is an important concern, data on operator exposure are lacking. Radiation dose to interventional radiologists during CT fluoroscopy-guided renal cryoablation (n = 20) and lung RFA (n = 20) was measured prospectively in a clinical setting. Effective dose to the operator was calculated from the 1-cm dose equivalent measured on the neck outside the lead apron, and on the left chest inside the lead apron, using electronic dosimeters. Equivalent dose to the operator's finger skin was measured using thermoluminescent dosimeter rings. The mean (median) effective dose to the operator per procedure was 6.05 (4.52) μSv during renal cryoablation and 0.74 (0.55) μSv during lung RFA. The mean (median) equivalent dose to the operator's finger skin per procedure was 2.1 (2.1) mSv during renal cryoablation, and 0.3 (0.3) mSv during lung RFA. Radiation dose to interventional radiologists during renal cryoablation and lung RFA were at an acceptable level, and in line with recommended dose limits for occupational radiation exposure.

Method and system for data clustering for very large databases

NASA Technical Reports Server (NTRS)

Livny, Miron (Inventor); Zhang, Tian (Inventor); Ramakrishnan, Raghu (Inventor)

1998-01-01

Multi-dimensional data contained in very large databases is efficiently and accurately clustered to determine patterns therein and extract useful information from such patterns. Conventional computer processors may be used which have limited memory capacity and conventional operating speed, allowing massive data sets to be processed in a reasonable time and with reasonable computer resources. The clustering process is organized using a clustering feature tree structure wherein each clustering feature comprises the number of data points in the cluster, the linear sum of the data points in the cluster, and the square sum of the data points in the cluster. A dense region of data points is treated collectively as a single cluster, and points in sparsely occupied regions can be treated as outliers and removed from the clustering feature tree. The clustering can be carried out continuously with new data points being received and processed, and with the clustering feature tree being restructured as necessary to accommodate the information from the newly received data points.

Maximum likelihood estimation of signal detection model parameters for the assessment of two-stage diagnostic strategies.

PubMed

Lirio, R B; Dondériz, I C; Pérez Abalo, M C

1992-08-01

The methodology of Receiver Operating Characteristic curves based on the signal detection model is extended to evaluate the accuracy of two-stage diagnostic strategies. A computer program is developed for the maximum likelihood estimation of parameters that characterize the sensitivity and specificity of two-stage classifiers according to this extended methodology. Its use is briefly illustrated with data collected in a two-stage screening for auditory defects.

Robotic Telepresence: Perception, Performance, and User Experience

DTIC Science & Technology

2012-02-01

defined as “a human-computer-machine condition in which a user receives sufficient information about a remote, real-world site through a machine so...that the user feels physically present at the remote, real-world site ” (Aliberti and Bruen, 2006). Telepresence often includes capabilities for a more...outdoor route reconnaissance course (figures 4 and 5) was located at the Molnar MOUT (Military Operations in Urban Terrain) site in Fort Benning, GA. It

Multilevel UQ strategies for large-scale multiphysics applications: PSAAP II solar receiver

NASA Astrophysics Data System (ADS)

Jofre, Lluis; Geraci, Gianluca; Iaccarino, Gianluca

2017-06-01

Uncertainty quantification (UQ) plays a fundamental part in building confidence in predictive science. Of particular interest is the case of modeling and simulating engineering applications where, due to the inherent complexity, many uncertainties naturally arise, e.g. domain geometry, operating conditions, errors induced by modeling assumptions, etc. In this regard, one of the pacing items, especially in high-fidelity computational fluid dynamics (CFD) simulations, is the large amount of computing resources typically required to propagate incertitude through the models. Upcoming exascale supercomputers will significantly increase the available computational power. However, UQ approaches cannot entrust their applicability only on brute force Monte Carlo (MC) sampling; the large number of uncertainty sources and the presence of nonlinearities in the solution will make straightforward MC analysis unaffordable. Therefore, this work explores the multilevel MC strategy, and its extension to multi-fidelity and time convergence, to accelerate the estimation of the effect of uncertainties. The approach is described in detail, and its performance demonstrated on a radiated turbulent particle-laden flow case relevant to solar energy receivers (PSAAP II: Particle-laden turbulence in a radiation environment). Investigation funded by DoE's NNSA under PSAAP II.

An Application of the "Virtual Spacecraft" Concept in Evaluation of the Mars Pathfinder Lander Low Gain Antenna

NASA Technical Reports Server (NTRS)

Pogorzelski, R. J.; Beckon, R. J.

1997-01-01

The virtual spacecraft concept is embodied in a set of subsystems, either in the form of hardware or computational models, which together represent all, or a portion of, a spacecraft. For example, the telecommunications transponder may be a hardware prototype while the propulsion system may exist only as a simulation. As the various subsystems are realized in hardware, the spacecraft becomes progressively less virtual. This concept is enabled by JPL's Mission System Testbed which is a set of networked workstations running a message passing operating system called "TRAMEL" which stands for Task Remote Asynchronous Message Exchange Layer. Each simulation on the workstations, which may in fact be hardware controlled by the workstation, "publishes" its operating parameters on TRAMEL and other simulations requiring those parameters as input may "subscribe" to them. In this manner, the whole simulation operates as a single virtual system. This paper describes a simulation designed to evaluate a communications link between the earth and the Mars Pathfinder Lander module as it descends under a parachute through the Martian atmosphere toward the planet's surface. This link includes a transmitter and a low gain antenna on the spacecraft and a receiving antenna and receiver on the earth as well as a simulation of the dynamics of the spacecraft. The transmitter, the ground station antenna, the receiver and the dynamics are all simulated computationally while the spacecraft antenna is implemented in hardware on a very simple spacecraft mockup. The dynamics simulation is a record of one output of the ensemble of outputs of a Monte Carlo simulation of the descent. Additionally, the antenna/spacecraft mock-up system was simulated using APATCH, a shooting and bouncing ray code developed by Demaco, Inc. The antenna simulation, the antenna hardware, and the link simulation are all physically located in different facilities at JPL separated by several hundred meters and are linked via the local area network (LAN).

A coded tracking telemetry system

USGS Publications Warehouse

Howey, P.W.; Seegar, W.S.; Fuller, M.R.; Titus, K.; Amlaner, Charles J.

1989-01-01

We describe the general characteristics of an automated radio telemetry system designed to operate for prolonged periods on a single frequency. Each transmitter sends a unique coded signal to a receiving system that encodes and records only the appropriater, pre-programmed codes. A record of the time of each reception is stored on diskettes in a micro-computer. This system enables continuous monitoring of infrequent signals (e.g. one per minute or one per hour), thus extending operation life or allowing size reduction of the transmitter, compared to conventional wildlife telemetry. Furthermore, when using unique codes transmitted on a single frequency, biologists can monitor many individuals without exceeding the radio frequency allocations for wildlife.

Apparatus and method for fusion of compute and switching functions of exascale system into a single component by using configurable network-on-chip fabric with distributed dual mode input-output ports and programmable network interfaces

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khare, Surhud; Somasekhar, Dinesh; More, Ankit

Described is an apparatus which comprises: a Network-On-Chip fabric using crossbar switches, having distributed ingress and egress ports; and a dual-mode network interface coupled to at least one crossbar switch, the dual-mode network interface is to include: a dual-mode circuitry; a controller operable to: configure the dual-mode circuitry to transmit and receive differential signals via the egress and ingress ports, respectively, and configure the dual-mode circuitry to transmit and receive signal-ended signals via the egress and ingress ports, respectively.

Embedded systems for supporting computer accessibility.

PubMed

Mulfari, Davide; Celesti, Antonio; Fazio, Maria; Villari, Massimo; Puliafito, Antonio

2015-01-01

Nowadays, customized AT software solutions allow their users to interact with various kinds of computer systems. Such tools are generally available on personal devices (e.g., smartphones, laptops and so on) commonly used by a person with a disability. In this paper, we investigate a way of using the aforementioned AT equipments in order to access many different devices without assistive preferences. The solution takes advantage of open source hardware and its core component consists of an affordable Linux embedded system: it grabs data coming from the assistive software, which runs on the user's personal device, then, after processing, it generates native keyboard and mouse HID commands for the target computing device controlled by the end user. This process supports any operating system available on the target machine and it requires no specialized software installation; therefore the user with a disability can rely on a single assistive tool to control a wide range of computing platforms, including conventional computers and many kinds of mobile devices, which receive input commands through the USB HID protocol.

Quantitative computer tomography analysis of post-operative subdural fluid volume predicts recurrence of chronic subdural haematoma.

PubMed

Xu, Fei-Fan; Chen, Jin-Hong; Leung, Gilberto Ka Kit; Hao, Shu-Yu; Xu, Long; Hou, Zong-Gang; Mao, Xiang; Shi, Guang-Zhi; Li, Jing-Sheng; Liu, Bai-Yun

2014-01-01

Post-operative volume of subdural fluid is considered to correlate with recurrence in chronic subdural haematoma (CSDH). Information on the applications of computer-assisted volumetric analysis in patients with CSDHs is lacking. To investigate the relationship between haematoma recurrence and longitudinal changes in subdural fluid volume using CT volumetric analysis. Fifty-four patients harbouring 64 CSDHs were studied prospectively. The association between recurrence rate and CT findings were investigated. Eleven patients (20.4%) experienced post-operative recurrence. Higher pre-operative (over 120 ml) and/or pre-discharge subdural fluid volumes (over 22 ml) were significantly associated with recurrence; the probability of non-recurrence for values below these thresholds were 92.7% and 95.2%, respectively. CSDHs with larger pre-operative (over 15.1 mm) and/or residual (over 11.7 mm) widths also had significantly increased recurrence rates. Bilateral CSDHs were not found to be more likely to recur in this series. On receiver-operating characteristic curve, the areas under curve for the magnitude of changes in subdural fluid volume were greater than a single time-point measure of either width or volume of the subdural fluid cavity. Close imaging follow-up is important for CSDH patients for recurrence prediction. Using quantitative CT volumetric analysis, strong evidence was provided that changes in the residual fluid volume during the 'self-resolution' period can be used as significantly radiological predictors of recurrence.

Spaceborne synthetic aperture radar signal processing using FPGAs

NASA Astrophysics Data System (ADS)

Sugimoto, Yohei; Ozawa, Satoru; Inaba, Noriyasu

2017-10-01

Synthetic Aperture Radar (SAR) imagery requires image reproduction through successive signal processing of received data before browsing images and extracting information. The received signal data records of the ALOS-2/PALSAR-2 are stored in the onboard mission data storage and transmitted to the ground. In order to compensate the storage usage and the capacity of transmission data through the mission date communication networks, the operation duty of the PALSAR-2 is limited. This balance strongly relies on the network availability. The observation operations of the present spaceborne SAR systems are rigorously planned by simulating the mission data balance, given conflicting user demands. This problem should be solved such that we do not have to compromise the operations and the potential of the next-generation spaceborne SAR systems. One of the solutions is to compress the SAR data through onboard image reproduction and information extraction from the reproduced images. This is also beneficial for fast delivery of information products and event-driven observations by constellation. The Emergence Studio (Sōhatsu kōbō in Japanese) with Japan Aerospace Exploration Agency is developing evaluation models of FPGA-based signal processing system for onboard SAR image reproduction. The model, namely, "Fast L1 Processor (FLIP)" developed in 2016 can reproduce a 10m-resolution single look complex image (Level 1.1) from ALOS/PALSAR raw signal data (Level 1.0). The processing speed of the FLIP at 200 MHz results in twice faster than CPU-based computing at 3.7 GHz. The image processed by the FLIP is no way inferior to the image processed with 32-bit computing in MATLAB.

PSC algorithm description

NASA Technical Reports Server (NTRS)

Nobbs, Steven G.

1995-01-01

An overview of the performance seeking control (PSC) algorithm and details of the important components of the algorithm are given. The onboard propulsion system models, the linear programming optimization, and engine control interface are described. The PSC algorithm receives input from various computers on the aircraft including the digital flight computer, digital engine control, and electronic inlet control. The PSC algorithm contains compact models of the propulsion system including the inlet, engine, and nozzle. The models compute propulsion system parameters, such as inlet drag and fan stall margin, which are not directly measurable in flight. The compact models also compute sensitivities of the propulsion system parameters to change in control variables. The engine model consists of a linear steady state variable model (SSVM) and a nonlinear model. The SSVM is updated with efficiency factors calculated in the engine model update logic, or Kalman filter. The efficiency factors are used to adjust the SSVM to match the actual engine. The propulsion system models are mathematically integrated to form an overall propulsion system model. The propulsion system model is then optimized using a linear programming optimization scheme. The goal of the optimization is determined from the selected PSC mode of operation. The resulting trims are used to compute a new operating point about which the optimization process is repeated. This process is continued until an overall (global) optimum is reached before applying the trims to the controllers.

[Experiences with an anesthesia protocol written by computer].

PubMed

Karliczek, G F; Brenken, U; van den Broeke, J J; Mooi, B; de Geus, A F; Wiersma, G; Oosterhaven, S

1988-04-01

Since December 1983, we have used a computer system for charting and data logging in cardiac and thoracic anesthesia. These computers, designed as stand-alone units, were developed at our hospital based on Motorola 6809 microprocessor systems. All measurements derived from anesthetic monitoring, ventilator, and heart-lung machine are automatically sampled at regular intervals and stored for later data management. Laboratory results are automatically received from the hospital computer system. The user communicates with the system via a terminal and a keyboard; this also facilitates the entering of all comments, medications, infusions, and fluid losses. All data are continuously displayed on an A3 format anesthetic chart using a multi-pen, flat-bed plotter. The operation of the system has proved to be simple and needs less time than charting by hand, while the result, the display on the chart, is far clearer and more complete than any handwritten document. Up to now 3,200 operations (corresponding to 12,500 anesthetic h) have been documented. The failure rate of the system, defined as an interruption of the documentation for more than 30 min is 2.1%. Further development of the system is discussed. A data base for processing the stored data has been developed and is being tested at present.

A new computer-based Farnsworth Munsell 100-hue test for evaluation of color vision.

PubMed

Ghose, Supriyo; Parmar, Twinkle; Dada, Tanuj; Vanathi, Murugesan; Sharma, Sourabh

2014-08-01

To evaluate a computer-based Farnsworth-Munsell (FM) 100-hue test and compare it with a manual FM 100-hue test in normal and congenital color-deficient individuals. Fifty color defective subjects and 200 normal subjects with a best-corrected visual acuity ≥ 6/12 were compared using a standard manual FM 100-hue test and a computer-based FM 100-hue test under standard operating conditions as recommended by the manufacturer after initial trial testing. Parameters evaluated were total error scores (TES), type of defect and testing time. Pearson's correlation coefficient was used to determine the relationship between the test scores. Cohen's kappa was used to assess agreement of color defect classification between the two tests. A receiver operating characteristic curve was used to determine the optimal cut-off score for the computer-based FM 100-hue test. The mean time was 16 ± 1.5 (range 6-20) min for the manual FM 100-hue test and 7.4 ± 1.4 (range 5-13) min for the computer-based FM 100-hue test, thus reducing testing time to <50 % (p < 0.05). For grading color discrimination, Pearson's correlation coefficient for TES between the two tests was 0.91 (p < 0.001). For color defect classification, Cohen's agreement coefficient was 0.98 (p < 0.01). The computer-based FM 100-hue is an effective and rapid method for detecting, classifying and grading color vision anomalies.

Object Classification Based on Analysis of Spectral Characteristics of Seismic Signal Envelopes

NASA Astrophysics Data System (ADS)

Morozov, Yu. V.; Spektor, A. A.

2017-11-01

A method for classifying moving objects having a seismic effect on the ground surface is proposed which is based on statistical analysis of the envelopes of received signals. The values of the components of the amplitude spectrum of the envelopes obtained applying Hilbert and Fourier transforms are used as classification criteria. Examples illustrating the statistical properties of spectra and the operation of the seismic classifier are given for an ensemble of objects of four classes (person, group of people, large animal, vehicle). It is shown that the computational procedures for processing seismic signals are quite simple and can therefore be used in real-time systems with modest requirements for computational resources.

Understanding and manipulating the RF fields at high field MRI

PubMed Central

Ibrahim, Tamer S.; Hue, YiK-Kiong; Tang, Lin

2015-01-01

This paper presents a complete overview of the electromagnetics (radiofrequency aspect) of MRI at low and high fields. Using analytical formulations, numerical modeling (computational electromagnetics), and ultrahigh field imaging experiments, the physics that impacts the electromagnetic quantities associated with MRI, namely (1) the transmit field, (2) receive field, and (3) total electromagnetic power absorption, is analyzed. The physical interpretation of the above-mentioned quantities is investigated by electromagnetic theory, to understand ‘What happens, in terms of electromagnetics, when operating at different static field strengths?’ Using experimental studies and numerical simulations, this paper also examines the physical and technological feasibilities by which all or any of these specified electromagnetic quantities can be manipulated through techniques such as B1 shimming (phased array excitation) and signal combination using a receive array in order to advance MRI at high field strengths. Pertinent to this subject and with highly coupled coils operating at 7 T, this paper also presents the first phantom work on B1 shimming without B1 measurements. PMID:19621335

Highly precise acoustic calibration method of ring-shaped ultrasound transducer array for plane-wave-based ultrasound tomography

NASA Astrophysics Data System (ADS)

Terada, Takahide; Yamanaka, Kazuhiro; Suzuki, Atsuro; Tsubota, Yushi; Wu, Wenjing; Kawabata, Ken-ichi

2017-07-01

Ultrasound computed tomography (USCT) is promising for a non-invasive, painless, operator-independent and quantitative system for breast-cancer screening. Assembly error, production tolerance, and aging-degradation variations of the hardwire components, particularly of plane-wave-based USCT systems, may hamper cost effectiveness, precise imaging, and robust operation. The plane wave is transmitted from a ring-shaped transducer array for receiving the signal at a high signal-to-noise-ratio and fast aperture synthesis. There are four signal-delay components: response delays in the transmitters and receivers and propagation delays depending on the positions of the transducer elements and their directivity. We developed a highly precise calibration method for calibrating these delay components and evaluated it with our prototype plane-wave-based USCT system. Our calibration method was found to be effective in reducing delay errors. Gaps and curves were eliminated from the plane wave, and echo images of wires were sharpened in the entire imaging area.

A computer-aided approach to detect the fetal behavioral states using multi-sensor Magnetocardiographic recordings.

PubMed

Vairavan, S; Ulusar, U D; Eswaran, H; Preissl, H; Wilson, J D; Mckelvey, S S; Lowery, C L; Govindan, R B

2016-02-01

We propose a novel computational approach to automatically identify the fetal heart rate patterns (fHRPs), which are reflective of sleep/awake states. By combining these patterns with presence or absence of movements, a fetal behavioral state (fBS) was determined. The expert scores were used as the gold standard and objective thresholds for the detection procedure were obtained using Receiver Operating Characteristics (ROC) analysis. To assess the performance, intraclass correlation was computed between the proposed approach and the mutually agreed expert scores. The detected fHRPs were then associated to their corresponding fBS based on the fetal movement obtained from fetal magnetocardiogaphic (fMCG) signals. This approach may aid clinicians in objectively assessing the fBS and monitoring fetal wellbeing. Copyright © 2015 Elsevier Ltd. All rights reserved.

Looking at Earth from space: Direct readout from environmental satellites

NASA Technical Reports Server (NTRS)

1994-01-01

Direct readout is the capability to acquire information directly from meteorological satellites. Data can be acquired from NASA-developed, National Oceanic and Atmospheric Administration (NOAA)-operated satellites, as well as from other nations' meteorological satellites. By setting up a personal computer-based ground (Earth) station to receive satellite signals, direct readout may be obtained. The electronic satellite signals are displayed as images on the computer screen. The images can display gradients of the Earth's topography and temperature, cloud formations, the flow and direction of winds and water currents, the formation of hurricanes, the occurrence of an eclipse, and a view of Earth's geography. Both visible and infrared images can be obtained. This booklet introduces the satellite systems, ground station configuration, and computer requirements involved in direct readout. Also included are lists of associated resources and vendors.

Identifying Factors That Predict Promotion Time to E-4 and Re-Enlistment Eligibility for U.S. Marine Corps Field Radio Operators

DTIC Science & Technology

2014-12-01

Primary Military Occupational Specialty PRO Proficiency Q-Q Quantile - Quantile RSS Residual Sum of Squares SI Shop Information T&R Training and...construct multivariate linear regression models to estimate Marines’ Computed Tier Score and time to achieve E-4 based on their individual personal...Science (GS) score, ASVAB Mathematics Knowledge (MK) score, ASVAB Paragraph Comprehension (PC) score, weight , and whether a Marine receives a weight

Analysis of components of variance in multiple-reader studies of computer-aided diagnosis with different tasks

NASA Astrophysics Data System (ADS)

Beiden, Sergey V.; Wagner, Robert F.; Campbell, Gregory; Metz, Charles E.; Chan, Heang-Ping; Nishikawa, Robert M.; Schnall, Mitchell D.; Jiang, Yulei

2001-06-01

In recent years, the multiple-reader, multiple-case (MRMC) study paradigm has become widespread for receiver operating characteristic (ROC) assessment of systems for diagnostic imaging and computer-aided diagnosis. We review how MRMC data can be analyzed in terms of the multiple components of the variance (case, reader, interactions) observed in those studies. Such information is useful for the design of pivotal studies from results of a pilot study and also for studying the effects of reader training. Recently, several of the present authors have demonstrated methods to generalize the analysis of multiple variance components to the case where unaided readers of diagnostic images are compared with readers who receive the benefit of a computer assist (CAD). For this case it is necessary to model the possibility that several of the components of variance might be reduced when readers incorporate the computer assist, compared to the unaided reading condition. We review results of this kind of analysis on three previously published MRMC studies, two of which were applications of CAD to diagnostic mammography and one was an application of CAD to screening mammography. The results for the three cases are seen to differ, depending on the reader population sampled and the task of interest. Thus, it is not possible to generalize a particular analysis of variance components beyond the tasks and populations actually investigated.

Support for non-locking parallel reception of packets belonging to a single memory reception FIFO

DOEpatents

Chen, Dong [Yorktown Heights, NY; Heidelberger, Philip [Yorktown Heights, NY; Salapura, Valentina [Yorktown Heights, NY; Senger, Robert M [Yorktown Heights, NY; Steinmacher-Burow, Burkhard [Boeblingen, DE; Sugawara, Yutaka [Yorktown Heights, NY

2011-01-27

A method and apparatus for distributed parallel messaging in a parallel computing system. A plurality of DMA engine units are configured in a multiprocessor system to operate in parallel, one DMA engine unit for transferring a current packet received at a network reception queue to a memory location in a memory FIFO (rmFIFO) region of a memory. A control unit implements logic to determine whether any prior received packet destined for that rmFIFO is still in a process of being stored in the associated memory by another DMA engine unit of the plurality, and prevent the one DMA engine unit from indicating completion of storing the current received packet in the reception memory FIFO (rmFIFO) until all prior received packets destined for that rmFIFO are completely stored by the other DMA engine units. Thus, there is provided non-locking support so that multiple packets destined for a single rmFIFO are transferred and stored in parallel to predetermined locations in a memory.

Basic concepts and development of an all-purpose computer interface for ROC/FROC observer study.

PubMed

Shiraishi, Junji; Fukuoka, Daisuke; Hara, Takeshi; Abe, Hiroyuki

2013-01-01

In this study, we initially investigated various aspects of requirements for a computer interface employed in receiver operating characteristic (ROC) and free-response ROC (FROC) observer studies which involve digital images and ratings obtained by observers (radiologists). Secondly, by taking into account these aspects, an all-purpose computer interface utilized for these observer performance studies was developed. Basically, the observer studies can be classified into three paradigms, such as one rating for one case without an identification of a signal location, one rating for one case with an identification of a signal location, and multiple ratings for one case with identification of signal locations. For these paradigms, display modes on the computer interface can be used for single/multiple views of a static image, continuous viewing with cascade images (i.e., CT, MRI), and dynamic viewing of movies (i.e., DSA, ultrasound). Various functions on these display modes, which include windowing (contrast/level), magnifications, and annotations, are needed to be selected by an experimenter corresponding to the purpose of the research. In addition, the rules of judgment for distinguishing between true positives and false positives are an important factor for estimating diagnostic accuracy in an observer study. We developed a computer interface which runs on a Windows operating system by taking into account all aspects required for various observer studies. This computer interface requires experimenters to have sufficient knowledge about ROC/FROC observer studies, but allows its use for any purpose of the observer studies. This computer interface will be distributed publicly in the near future.

Remote Operation of the Fermilab/NICADD Photoinjector

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nikolai Barov et al.

2002-03-21

The recognition that a new major HEP facility must receive international support and that its execution would benefit from worldwide interaction from design through operation has given rise to the term Global Accelerator Network (GAN). A welcome consequence has been a more permissive attitude toward remote operation of existing facilities.For roughly thirty years, the computer has been the principal operator interface to the beam,and, through the development of the Internet, the operator can be literally anywhere. In this note, the authors describe their approach to enabling a sufficient degree of operation of the photoinjector from afar in order to carrymore » out investigations in beam physics. The goal was to do so on a time scale of a few months and at minimal cost. At this writing, remote shifts are routinely scheduled involving DESY and LBL, limited in frequency only by the requests of the collaborators and by the need for time to interpret the data.« less

Architecture for a 1-GHz Digital RADAR

NASA Technical Reports Server (NTRS)

Mallik, Udayan

2011-01-01

An architecture for a Direct RF-digitization Type Digital Mode RADAR was developed at GSFC in 2008. Two variations of a basic architecture were developed for use on RADAR imaging missions using aircraft and spacecraft. Both systems can operate with a pulse repetition rate up to 10 MHz with 8 received RF samples per pulse repetition interval, or at up to 19 kHz with 4K received RF samples per pulse repetition interval. The first design describes a computer architecture for a Continuous Mode RADAR transceiver with a real-time signal processing and display architecture. The architecture can operate at a high pulse repetition rate without interruption for an infinite amount of time. The second design describes a smaller and less costly burst mode RADAR that can transceive high pulse repetition rate RF signals without interruption for up to 37 seconds. The burst-mode RADAR was designed to operate on an off-line signal processing paradigm. The temporal distribution of RF samples acquired and reported to the RADAR processor remains uniform and free of distortion in both proposed architectures. The majority of the RADAR's electronics is implemented in digital CMOS (complementary metal oxide semiconductor), and analog circuits are restricted to signal amplification operations and analog to digital conversion. An implementation of the proposed systems will create a 1-GHz, Direct RF-digitization Type, L-Band Digital RADAR--the highest band achievable for Nyquist Rate, Direct RF-digitization Systems that do not implement an electronic IF downsample stage (after the receiver signal amplification stage), using commercially available off-the-shelf integrated circuits.

Performance Analysis of Control Signal Transmission Technique for Cognitive Radios in Dynamic Spectrum Access Networks

NASA Astrophysics Data System (ADS)

Sakata, Ren; Tomioka, Tazuko; Kobayashi, Takahiro

When cognitive radio (CR) systems dynamically use the frequency band, a control signal is necessary to indicate which carrier frequencies are currently available in the network. In order to keep efficient spectrum utilization, this control signal also should be transmitted based on the channel conditions. If transmitters dynamically select carrier frequencies, receivers have to receive control signals without knowledge of their carrier frequencies. To enable such transmission and reception, this paper proposes a novel scheme called DCPT (Differential Code Parallel Transmission). With DCPT, receivers can receive low-rate information with no knowledge of the carrier frequencies. The transmitter transmits two signals whose carrier frequencies are spaced by a predefined value. The absolute values of the carrier frequencies can be varied. When the receiver acquires the DCPT signal, it multiplies the signal by a frequency-shifted version of the signal; this yields a DC component that represents the data signal which is then demodulated. The performance was evaluated by means of numerical analysis and computer simulation. We confirmed that DCPT operates successfully even under severe interference if its parameters are appropriately configured.

MERCATOR: Methods and Realization for Control of the Attitude and the Orbit of spacecraft

NASA Technical Reports Server (NTRS)

Tavernier, Gilles; Campan, Genevieve

1993-01-01

Since 1974, CNES has been involved in geostationary positioning. Among different entities participating in operations and their preparation, the Flight Dynamics Center (FDC) is in charge of performing the following tasks: orbit determination; attitude determination; computation, monitoring, and calibration of orbit maneuvers; computation, monitoring, and calibration of attitude maneuvers; and operational predictions. In order to fulfill this mission, the FDC receives telemetry from the satellite and localization measurements from ground stations (e.g., CNES, NASA, INTELSAT). These data are processed by space dynamics programs integrated in the MERCATOR system which is run on SUN workstations (UNIX O.S.). The main features of MERCATOR are redundancy, modularity, and flexibility: efficient, flexible, and user friendly man-machine interface; and four identical SUN stations redundantly linked in an Ethernet network. Each workstation can perform all the tasks from data acquisition to computation results dissemination through a video network. A team of four engineers can handle the space mechanics aspects of a complete geostationary positioning from the injection into a transfer orbit to the final maneuvers in the station-keeping window. MERCATOR has been or is to be used for operations related to more than ten geostationary positionings. Initially developed for geostationary satellites, MERCATOR's methodology was also used for satellite control centers and can be applied to a wide range of satellites and to future manned missions.

Control of coherent information via on-chip photonic-phononic emitter-receivers.

PubMed

Shin, Heedeuk; Cox, Jonathan A; Jarecki, Robert; Starbuck, Andrew; Wang, Zheng; Rakich, Peter T

2015-03-05

Rapid progress in integrated photonics has fostered numerous chip-scale sensing, computing and signal processing technologies. However, many crucial filtering and signal delay operations are difficult to perform with all-optical devices. Unlike photons propagating at luminal speeds, GHz-acoustic phonons moving at slower velocities allow information to be stored, filtered and delayed over comparatively smaller length-scales with remarkable fidelity. Hence, controllable and efficient coupling between coherent photons and phonons enables new signal processing technologies that greatly enhance the performance and potential impact of integrated photonics. Here we demonstrate a mechanism for coherent information processing based on travelling-wave photon-phonon transduction, which achieves a phonon emit-and-receive process between distinct nanophotonic waveguides. Using this device, physics--which supports GHz frequencies--we create wavelength-insensitive radiofrequency photonic filters with frequency selectivity, narrow-linewidth and high power-handling in silicon. More generally, this emit-receive concept is the impetus for enabling new signal processing schemes.

Testing of CMA-2000 Microwave Landing System (MLS) airborne receiver

NASA Astrophysics Data System (ADS)

Labreche, L.; Murfin, A. J.

1989-09-01

Microwave landing system (MLS) is a precision approach and landing guidance system which provides position information and various air to ground data. Position information is provided on a wide coverage sector and is determined by an azimuth angle measurement, an elevation angle measurement, and a range measurement. MLS performance standards and testing of the MLS airborne receiver is mainly governed by Technical Standard Order TSO-C104 issued by the Federal Aviation Administration. This TSO defines detailed test procedures for use in determining the required performance under standard and stressed conditions. It also imposes disciplines on software development and testing procedures. Testing performed on the CMA-2000 MLS receiver and methods used in its validation are described. A computer automated test system has been developed to test for compliance with RTCA/DO-177 Minimum Operation Performance Standards. Extensive software verification and traceability tests designed to ensure compliance with RTCA/DO-178 are outlined.

Dilutional hyponatraemia: a cause of massive fatal intraoperative cerebral oedema in a child undergoing renal transplantation.

PubMed

Armour, A

1997-05-01

A four year old boy with polyuric renal failure resulting from recurrent urinary tract infections and vesicoureteric reflux from birth underwent renal transplantation. In the past he had had five ureteric reimplant operations and a gastrostomy, as he ate nothing by mouth. He required peritoneal dialysis 13 hours a night, six nights a week. His fluid requirements were 2100 ml per day. This included a night feed of 1.5 litres Nutrizon. Before operation he received 900 ml of Dioralyte instead of the Nutrizon feed, and peritoneal dialysis was performed as usual. The operation itself was technically difficult and there was more blood loss than anticipated, requiring intravenous fluids and blood. The operation ended about four hours later but he did not wake up. Urgent computed tomography revealed gross cerebral oedema. He died the next day. At necropsy the brain was massively oedematous and weighed 1680 g.

Hydrodynamics Analysis and CFD Simulation of Portal Venous System by TIPS and LS.

PubMed

Wang, Meng; Zhou, Hongyu; Huang, Yaozhen; Gong, Piyun; Peng, Bing; Zhou, Shichun

2015-06-01

In cirrhotic patients, portal hypertension is often associated with a hyperdynamic changes. Transjugular Intrahepatic Portosystemic Shunt (TIPS) and Laparoscopic splenectomy are both treatments for liver cirrhosis due to portal hypertension. While, the two different interventions have different effects on hemodynamics after operation and the possibilities of triggering PVT are different. How hemodynamics of portal vein system evolving with two different operations remain unknown. Based on ultrasound and established numerical methods, CFD technique is applied to analyze hemodynamic changes after TIPS and Laparoscopic splenectomy. In this paper, we applied two 3-D flow models to the hemodynamic analysis for two patients who received a TIPS and a laparoscopic splenectomy, both therapies for treating portal hypertension induced diseases. The current computer simulations give a quantitative analysis of the interplay between hemodynamics and TIPS or splenectomy. In conclusion, the presented computational model can be used for the theoretical analysis of TIPS and laparoscopic splenectomy, clinical decisions could be made based on the simulation results with personal properly treatment.

Integrable subsectors from holography

NASA Astrophysics Data System (ADS)

de Mello Koch, Robert; Kim, Minkyoo; Van Zyl, Hendrik J. R.

2018-05-01

We consider operators in N=4 super Yang-Mills theory dual to closed string states propagating on a class of LLM geometries. The LLM geometries we consider are specified by a boundary condition that is a set of black rings on the LLM plane. When projected to the LLM plane, the closed strings are polygons with all corners lying on the outer edge of a single ring. The large N limit of correlators of these operators receives contributions from non-planar diagrams even for the leading large N dynamics. Our interest in these fluctuations is because a previous weak coupling analysis argues that the net effect of summing the huge set of non-planar diagrams, is a simple rescaling of the 't Hooft coupling. We carry out some nontrivial checks of this proposal. Using the su(2|2)2 symmetry we determine the two magnon S-matrix and demonstrate that it agrees, up to two loops, with a weak coupling computation performed in the CFT. We also compute the first finite size corrections to both the magnon and the dyonic magnon by constructing solutions to the Nambu-Goto action that carry finite angular momentum. These finite size computations constitute a strong coupling confirmation of the proposal.

Use of machine-learning classifiers to predict requests for preoperative acute pain service consultation.

PubMed

Tighe, Patrick J; Lucas, Stephen D; Edwards, David A; Boezaart, André P; Aytug, Haldun; Bihorac, Azra

2012-10-01

  The purpose of this project was to determine whether machine-learning classifiers could predict which patients would require a preoperative acute pain service (APS) consultation.   Retrospective cohort.   University teaching hospital.   The records of 9,860 surgical patients posted between January 1 and June 30, 2010 were reviewed.   Request for APS consultation. A cohort of machine-learning classifiers was compared according to its ability or inability to classify surgical cases as requiring a request for a preoperative APS consultation. Classifiers were then optimized utilizing ensemble techniques. Computational efficiency was measured with the central processing unit processing times required for model training. Classifiers were tested using the full feature set, as well as the reduced feature set that was optimized using a merit-based dimensional reduction strategy.   Machine-learning classifiers correctly predicted preoperative requests for APS consultations in 92.3% (95% confidence intervals [CI], 91.8-92.8) of all surgical cases. Bayesian methods yielded the highest area under the receiver operating curve (0.87, 95% CI 0.84-0.89) and lowest training times (0.0018 seconds, 95% CI, 0.0017-0.0019 for the NaiveBayesUpdateable algorithm). An ensemble of high-performing machine-learning classifiers did not yield a higher area under the receiver operating curve than its component classifiers. Dimensional reduction decreased the computational requirements for multiple classifiers, but did not adversely affect classification performance.   Using historical data, machine-learning classifiers can predict which surgical cases should prompt a preoperative request for an APS consultation. Dimensional reduction improved computational efficiency and preserved predictive performance. Wiley Periodicals, Inc.

CT colonography: influence of 3D viewing and polyp candidate features on interpretation with computer-aided detection.

PubMed

Shi, Rong; Schraedley-Desmond, Pamela; Napel, Sandy; Olcott, Eric W; Jeffrey, R Brooke; Yee, Judy; Zalis, Michael E; Margolis, Daniel; Paik, David S; Sherbondy, Anthony J; Sundaram, Padmavathi; Beaulieu, Christopher F

2006-06-01

To retrospectively determine if three-dimensional (3D) viewing improves radiologists' accuracy in classifying true-positive (TP) and false-positive (FP) polyp candidates identified with computer-aided detection (CAD) and to determine candidate polyp features that are associated with classification accuracy, with known polyps serving as the reference standard. Institutional review board approval and informed consent were obtained; this study was HIPAA compliant. Forty-seven computed tomographic (CT) colonography data sets were obtained in 26 men and 10 women (age range, 42-76 years). Four radiologists classified 705 polyp candidates (53 TP candidates, 652 FP candidates) identified with CAD; initially, only two-dimensional images were used, but these were later supplemented with 3D rendering. Another radiologist unblinded to colonoscopy findings characterized the features of each candidate, assessed colon distention and preparation, and defined the true nature of FP candidates. Receiver operating characteristic curves were used to compare readers' performance, and repeated-measures analysis of variance was used to test features that affect interpretation. Use of 3D viewing improved classification accuracy for three readers and increased the area under the receiver operating characteristic curve to 0.96-0.97 (P<.001). For TP candidates, maximum polyp width (P=.038), polyp height (P=.019), and preparation (P=.004) significantly affected accuracy. For FP candidates, colonic segment (P=.007), attenuation (P<.001), surface smoothness (P<.001), distention (P=.034), preparation (P<.001), and true nature of candidate lesions (P<.001) significantly affected accuracy. Use of 3D viewing increases reader accuracy in the classification of polyp candidates identified with CAD. Polyp size and examination quality are significantly associated with accuracy. Copyright (c) RSNA, 2006.

Xtalk: a path-based approach for identifying crosstalk between signaling pathways

PubMed Central

Tegge, Allison N.; Sharp, Nicholas; Murali, T. M.

2016-01-01

Motivation: Cells communicate with their environment via signal transduction pathways. On occasion, the activation of one pathway can produce an effect downstream of another pathway, a phenomenon known as crosstalk. Existing computational methods to discover such pathway pairs rely on simple overlap statistics. Results: We present Xtalk, a path-based approach for identifying pairs of pathways that may crosstalk. Xtalk computes the statistical significance of the average length of multiple short paths that connect receptors in one pathway to the transcription factors in another. By design, Xtalk reports the precise interactions and mechanisms that support the identified crosstalk. We applied Xtalk to signaling pathways in the KEGG and NCI-PID databases. We manually curated a gold standard set of 132 crosstalking pathway pairs and a set of 140 pairs that did not crosstalk, for which Xtalk achieved an area under the receiver operator characteristic curve of 0.65, a 12% improvement over the closest competing approach. The area under the receiver operator characteristic curve varied with the pathway, suggesting that crosstalk should be evaluated on a pathway-by-pathway level. We also analyzed an extended set of 658 pathway pairs in KEGG and to a set of more than 7000 pathway pairs in NCI-PID. For the top-ranking pairs, we found substantial support in the literature (81% for KEGG and 78% for NCI-PID). We provide examples of networks computed by Xtalk that accurately recovered known mechanisms of crosstalk. Availability and implementation: The XTALK software is available at http://bioinformatics.cs.vt.edu/~murali/software. Crosstalk networks are available at http://graphspace.org/graphs?tags=2015-bioinformatics-xtalk. Contact: ategge@vt.edu, murali@cs.vt.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:26400040

Efficacy of an artificial neural network-based approach to endoscopic ultrasound elastography in diagnosis of focal pancreatic masses.

PubMed

Săftoiu, Adrian; Vilmann, Peter; Gorunescu, Florin; Janssen, Jan; Hocke, Michael; Larsen, Michael; Iglesias-Garcia, Julio; Arcidiacono, Paolo; Will, Uwe; Giovannini, Marc; Dietrich, Cristoph F; Havre, Roald; Gheorghe, Cristian; McKay, Colin; Gheonea, Dan Ionuţ; Ciurea, Tudorel

2012-01-01

By using strain assessment, real-time endoscopic ultrasound (EUS) elastography provides additional information about a lesion's characteristics in the pancreas. We assessed the accuracy of real-time EUS elastography in focal pancreatic lesions using computer-aided diagnosis by artificial neural network analysis. We performed a prospective, blinded, multicentric study at of 258 patients (774 recordings from EUS elastography) who were diagnosed with chronic pancreatitis (n = 47) or pancreatic adenocarcinoma (n = 211) from 13 tertiary academic medical centers in Europe (the European EUS Elastography Multicentric Study Group). We used postprocessing software analysis to compute individual frames of elastography movies recorded by retrieving hue histogram data from a dynamic sequence of EUS elastography into a numeric matrix. The data then were analyzed in an extended neural network analysis, to automatically differentiate benign from malignant patterns. The neural computing approach had 91.14% training accuracy (95% confidence interval [CI], 89.87%-92.42%) and 84.27% testing accuracy (95% CI, 83.09%-85.44%). These results were obtained using the 10-fold cross-validation technique. The statistical analysis of the classification process showed a sensitivity of 87.59%, a specificity of 82.94%, a positive predictive value of 96.25%, and a negative predictive value of 57.22%. Moreover, the corresponding area under the receiver operating characteristic curve was 0.94 (95% CI, 0.91%-0.97%), which was significantly higher than the values obtained by simple mean hue histogram analysis, for which the area under the receiver operating characteristic was 0.85. Use of the artificial intelligence methodology via artificial neural networks supports the medical decision process, providing fast and accurate diagnoses. Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.

Method for transferring data from an unsecured computer to a secured computer

DOEpatents

Nilsen, Curt A.

1997-01-01

A method is described for transferring data from an unsecured computer to a secured computer. The method includes transmitting the data and then receiving the data. Next, the data is retransmitted and rereceived. Then, it is determined if errors were introduced when the data was transmitted by the unsecured computer or received by the secured computer. Similarly, it is determined if errors were introduced when the data was retransmitted by the unsecured computer or rereceived by the secured computer. A warning signal is emitted from a warning device coupled to the secured computer if (i) an error was introduced when the data was transmitted or received, and (ii) an error was introduced when the data was retransmitted or rereceived.

Use of computer systems and process information for blast furnace operations at U. S. Steel, Gary Works

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sherman, G.J.; Zmierski, M.L.

1994-09-01

US Steel Iron Producing Div. consists of four operating blast furnaces ranging in process control capabilities from 1950's and 1960's era hardware to state of the art technology. The oldest control system consists of a large number of panels containing numerous relays, indicating lights, selector switches, push buttons, analog controllers, strip chart recorders and annunciators. In contrast, the state of the art control system utilizes remote I/O, two sets of redundant PLC's, redundant charge director computer, redundant distributed control system, high resolution video-graphic display system and supervisory computer for real-time data acquisition. Process data are collected and archived on twomore » DEC VAX computers, one for No. 13 blast furnace and the other for the three south end furnaces. Historical trending, data analysis and reporting are available to iron producing personnel through terminals and PC's connected directly to the systems, dial-up modems and various network configurations. These two machines are part of the iron producing network which allows them to pass and receive information from each other as well as numerous other sources throughout the division. This configuration allows personnel to access most pertinent furnace information from a single source. The basic objective of the control systems is to charge raw materials to the top of the furnace at aim weights and sequence, while maintaining blast conditions at the bottom of the furnace at required temperature, pressure and composition. Control changes by the operators are primarily supervisory based on review of system generated plots and tables.« less

Surveying System

NASA Technical Reports Server (NTRS)

1988-01-01

Sunrise Geodetic Surveys are setting up their equipment for a town survey. Their equipment differs from conventional surveying systems that employ transit rod and chain to measure angles and distances. They are using ISTAC Inc.'s Model 2002 positioning system, which offers fast accurate surveying with exceptional signals from orbiting satellites. The special utility of the ISTAC Model 2002 is that it can provide positioning of the highest accuracy from Navstar PPS signals because it requires no knowledge of secret codes. It operates by comparing the frequency and time phase of a Navstar signal arriving at one ISTAC receiver with the reception of the same set of signals by another receiver. Data is computer processed and translated into three dimensional position data - latitude, longitude and elevation.

Adaptive frequency-domain equalization in digital coherent optical receivers.

PubMed

Faruk, Md Saifuddin; Kikuchi, Kazuro

2011-06-20

We propose a novel frequency-domain adaptive equalizer in digital coherent optical receivers, which can reduce computational complexity of the conventional time-domain adaptive equalizer based on finite-impulse-response (FIR) filters. The proposed equalizer can operate on the input sequence sampled by free-running analog-to-digital converters (ADCs) at the rate of two samples per symbol; therefore, the arbitrary initial sampling phase of ADCs can be adjusted so that the best symbol-spaced sequence is produced. The equalizer can also be configured in the butterfly structure, which enables demultiplexing of polarization tributaries apart from equalization of linear transmission impairments. The performance of the proposed equalization scheme is verified by 40-Gbits/s dual-polarization quadrature phase-shift keying (QPSK) transmission experiments.

Digital coherent receiver based transmitter penalty characterization.

PubMed

Geisler, David J; Kaufmann, John E

2016-12-26

For optical communications links where receivers are signal-power-starved, such as through free-space, it is important to design transmitters and receivers that can operate as close as practically possible to theoretical limits. A total system penalty is typically assessed in terms of how far the end-to-end bit-error rate (BER) is from these limits. It is desirable, but usually difficult, to determine the division of this penalty between the transmitter and receiver. This paper describes a new rigorous and computationally based method that isolates which portion of the penalty can be assessed against the transmitter. There are two basic parts to this approach: (1) use of a coherent optical receiver to perform frequency down-conversion of a transmitter's optical signal waveform to the electrical domain, preserving both optical field amplitude and phase information, and (2): software-based analysis of the digitized electrical waveform. The result is a single numerical metric that quantifies how close a transmitter's signal waveform is to the ideal, based on its BER performance with a perfect software-defined matched-filter receiver demodulator. A detailed description of applying the proposed methodology to the waveform characterization of an optical burst-mode differential phase-shifted keying (DPSK) transmitter is experimentally demonstrated.

Distributed Computation and TENEX-Related Activities

DTIC Science & Technology

1978-01-01

IPCF) which provides the inter-job communication functions required by MSG. MSG will be modified to use the IPCF primitives when running under TOPS...mmummi iiiwnrnrtnr’in i^WMBi. ■a^j.i.aiAj.k ■*"-’"’’"— •’ ’■■ BBN Report No. 3752 Bolt Beranek and Newman Inc. . . - . *. - primitive (e.g...from a process to MSG when a communication primitive is executed, and from MSG to a process when a pending event (e.g., outstanding receive operation

Managing Data From Signal-Propagation Experiments

NASA Technical Reports Server (NTRS)

Kantak, A. V.

1989-01-01

Computer programs generate characteristic plots from amplitudes and phases. Software system enables minicomputer to process data on amplitudes and phases of signals received during experiments in ground-mobile/satellite radio propagation. Takes advantage of file-handling capabilities of UNIX operating system and C programming language. Interacts with user, under whose guidance programs in FORTRAN language generate plots of spectra or other curves of types commonly used to characterize signals. FORTRAN programs used to process file-handling outputs into any of several useful forms.

Multi Sector Planning Tools for Trajectory-Based Operations

NASA Technical Reports Server (NTRS)

Prevot, Thomas; Mainini, Matthew; Brasil, Connie

2010-01-01

This paper discusses a suite of multi sector planning tools for trajectory-based operations that were developed and evaluated in the Airspace Operations Laboratory (AOL) at the NASA Ames Research Center. The toolset included tools for traffic load and complexity assessment as well as trajectory planning and coordination. The situation assessment tools included an integrated suite of interactive traffic displays, load tables, load graphs, and dynamic aircraft filters. The planning toolset allowed for single and multi aircraft trajectory planning and data communication-based coordination of trajectories between operators. Also newly introduced was a real-time computation of sector complexity into the toolset that operators could use in lieu of aircraft count to better estimate and manage sector workload, especially in situations with convective weather. The tools were used during a joint NASA/FAA multi sector planner simulation in the AOL in 2009 that had multiple objectives with the assessment of the effectiveness of the tools being one of them. Current air traffic control operators who were experienced as area supervisors and traffic management coordinators used the tools throughout the simulation and provided their usefulness and usability ratings in post simulation questionnaires. This paper presents these subjective assessments as well as the actual usage data that was collected during the simulation. The toolset was rated very useful and usable overall. Many elements received high scores by the operators and were used frequently and successfully. Other functions were not used at all, but various requests for new functions and capabilities were received that could be added to the toolset.

A real-time chirp-coded imaging system with tissue attenuation compensation.

PubMed

Ramalli, A; Guidi, F; Boni, E; Tortoli, P

2015-07-01

In ultrasound imaging, pulse compression methods based on the transmission (TX) of long coded pulses and matched receive filtering can be used to improve the penetration depth while preserving the axial resolution (coded-imaging). The performance of most of these methods is affected by the frequency dependent attenuation of tissue, which causes mismatch of the receiver filter. This, together with the involved additional computational load, has probably so far limited the implementation of pulse compression methods in real-time imaging systems. In this paper, a real-time low-computational-cost coded-imaging system operating on the beamformed and demodulated data received by a linear array probe is presented. The system has been implemented by extending the firmware and the software of the ULA-OP research platform. In particular, pulse compression is performed by exploiting the computational resources of a single digital signal processor. Each image line is produced in less than 20 μs, so that, e.g., 192-line frames can be generated at up to 200 fps. Although the system may work with a large class of codes, this paper has been focused on the test of linear frequency modulated chirps. The new system has been used to experimentally investigate the effects of tissue attenuation so that the design of the receive compression filter can be accordingly guided. Tests made with different chirp signals confirm that, although the attainable compression gain in attenuating media is lower than the theoretical value expected for a given TX Time-Bandwidth product (BT), good SNR gains can be obtained. For example, by using a chirp signal having BT=19, a 13 dB compression gain has been measured. By adapting the frequency band of the receiver to the band of the received echo, the signal-to-noise ratio and the penetration depth have been further increased, as shown by real-time tests conducted on phantoms and in vivo. In particular, a 2.7 dB SNR increase has been measured through a novel attenuation compensation scheme, which only requires to shift the demodulation frequency by 1 MHz. The proposed method characterizes for its simplicity and easy implementation. Copyright © 2015 Elsevier B.V. All rights reserved.

A simplified technique for polymethyl methacrylate cranioplasty: combined cotton stacking and finger fracture method.

PubMed

Kung, Woon-Man; Lin, Muh-Shi

2012-01-01

Polymethyl methacrylate (PMMA) is one of the most frequently used cranioplasty materials. However, limitations exist with PMMA cranioplasty including longer operative time, greater blood loss and a higher infection rate. To reduce these disadvantages, it is proposed to introduce a new surgical method for PMMA cranioplasty. Retrospective review of nine patients who received nine PMMA implants using combined cotton stacking and finger fracture method from January 2008 to July 2011. The definitive height of skull defect was quantified by computer-based image analysis of computed tomography (CT) scans. Aesthetic outcomes as measured by post-reduction radiographs and cranial index of symmetry (CIS), cranial nerve V and VII function and complications (wound infection, hardware extrusions, meningitis, osteomyelitis and brain abscess) were evaluated. The mean operation time for implant moulding was 24.56 ± 4.6 minutes and 178.0 ± 53 minutes for skin-to-skin. Average blood loss was 169 mL. All post-operative radiographs revealed excellent reduction. The mean CIS score was 95.86 ± 1.36%, indicating excellent symmetry. These results indicate the safety, practicability, excellent cosmesis, craniofacial symmetry and stability of this new surgical technique.

Portable Airborne Laser System Measures Forest-Canopy Height

NASA Technical Reports Server (NTRS)

Nelson, Ross

2005-01-01

(PALS) is a combination of laser ranging, video imaging, positioning, and data-processing subsystems designed for measuring the heights of forest canopies along linear transects from tens to thousands of kilometers long. Unlike prior laser ranging systems designed to serve the same purpose, the PALS is not restricted to use aboard a single aircraft of a specific type: the PALS fits into two large suitcases that can be carried to any convenient location, and the PALS can be installed in almost any local aircraft for hire, thereby making it possible to sample remote forests at relatively low cost. The initial cost and the cost of repairing the PALS are also lower because the PALS hardware consists mostly of commercial off-the-shelf (COTS) units that can easily be replaced in the field. The COTS units include a laser ranging transceiver, a charge-coupled-device camera that images the laser-illuminated targets, a differential Global Positioning System (dGPS) receiver capable of operation within the Wide Area Augmentation System, a video titler, a video cassette recorder (VCR), and a laptop computer equipped with two serial ports. The VCR and computer are powered by batteries; the other units are powered at 12 VDC from the 28-VDC aircraft power system via a low-pass filter and a voltage converter. The dGPS receiver feeds location and time data, at an update rate of 0.5 Hz, to the video titler and the computer. The laser ranging transceiver, operating at a sampling rate of 2 kHz, feeds its serial range and amplitude data stream to the computer. The analog video signal from the CCD camera is fed into the video titler wherein the signal is annotated with position and time information. The titler then forwards the annotated signal to the VCR for recording on 8-mm tapes. The dGPS and laser range and amplitude serial data streams are processed by software that displays the laser trace and the dGPS information as they are fed into the computer, subsamples the laser range and amplitude data, interleaves the subsampled data with the dGPS information, and records the resulting interleaved data stream.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Habte, A.; Sengupta, M.; Wilcox, S.

Models to compute Global Horizontal Irradiance (GHI) and Direct Normal Irradiance (DNI) have been in development over the last 3 decades. These models can be classified as empirical or physical, based on the approach. Empirical models relate ground based observations with satellite measurements and use these relations to compute surface radiation. Physical models consider the radiation received from the earth at the satellite and create retrievals to estimate surface radiation. While empirical methods have been traditionally used for computing surface radiation for the solar energy industry the advent of faster computing has made operational physical models viable. The Global Solarmore » Insolation Project (GSIP) is an operational physical model from NOAA that computes GHI using the visible and infrared channel measurements from the GOES satellites. GSIP uses a two-stage scheme that first retrieves cloud properties and uses those properties in a radiative transfer model to calculate surface radiation. NREL, University of Wisconsin and NOAA have recently collaborated to adapt GSIP to create a 4 km GHI and DNI product every 30 minutes. This paper presents an outline of the methodology and a comprehensive validation using high quality ground based solar data from the National Oceanic and Atmospheric Administration (NOAA) Surface Radiation (SURFRAD) (http://www.srrb.noaa.gov/surfrad/sitepage.html) and Integrated Surface Insolation Study (ISIS) http://www.srrb.noaa.gov/isis/isissites.html), the Solar Radiation Research Laboratory (SRRL) at National Renewable Energy Laboratory (NREL), and Sun Spot One (SS1) stations.« less

Algorithmic and heuristic processing of information by the nervous system.

PubMed

Restian, A

1980-01-01

Starting from the fact that the nervous system must discover the information it needs, the author describes the way it decodes the received message. The logical circuits of the nervous system, submitting the received signals to a process by means of which information brought is discovered step by step, participates in decoding the message. The received signals, as information, can be algorithmically or heuristically processed. Algorithmic processing is done according to precise rules, which must be fulfilled step by step. By algorithmic processing, one develops somatic and vegetative reflexes as blood pressure, heart frequency or water metabolism control. When it does not dispose of precise rules of information processing or when algorithmic processing needs a very long time, the nervous system must use heuristic processing. This is the feature that differentiates the human brain from the electronic computer that can work only according to some extremely precise rules. The human brain can work according to less precise rules because it can resort to trial and error operations, and because it works according to a form of logic. Working with superior order signals which represent the class of all inferior type signals from which they begin, the human brain need not perform all the operations that it would have to perform by superior type of signals. Therefore the brain tries to submit the received signals to intensive as possible superization. All informational processing, and especially heuristical processing, is accompanied by a certain affective color and the brain cannot operate without it. Emotions, passions and sentiments usually complete the lack of precision of the heuristical programmes. Finally, the author shows that informational and especially heuristical processes study can contribute to a better understanding of the transition from neurological to psychological activity.

Program on application of communications satellites to educational development

NASA Technical Reports Server (NTRS)

Morgan, R. P.; Singh, J. P.

1971-01-01

Interdisciplinary research in needs analysis, communications technology studies, and systems synthesis is reported. Existing and planned educational telecommunications services are studied and library utilization of telecommunications is described. Preliminary estimates are presented of ranges of utilization of educational telecommunications services for 1975 and 1985; instructional and public television, computer-aided instruction, computing resources, and information resource sharing for various educational levels and purposes. Communications technology studies include transmission schemes for still-picture television, use of Gunn effect devices, and TV receiver front ends for direct satellite reception at 12 GHz. Two major studies in the systems synthesis project concern (1) organizational and administrative aspects of a large-scale instructional satellite system to be used with schools and (2) an analysis of future development of instructional television, with emphasis on the use of video tape recorders and cable television. A communications satellite system synthesis program developed for NASA is now operational on the university IBM 360-50 computer.

The CCC system in two teaching hospitals: a progress report.

PubMed

Slack, W V; Bleich, H L

1999-06-01

Computing systems developed by the Center for Clinical Computing (CCC) have been in operation in Beth Israel and Brigham and Women's hospitals for over 10 years. Designed to be of direct benefit to doctors, nurses, and other clinicians in the care of their patients, the CCC systems give the results of diagnostic studies immediately upon request; offer access to the medical literature: give advice, consultation, alerts, and reminders; assist in the day-to-day practice to medicine, and participate directly in the education of medical students and house officers. The CCC systems are extensively used, even by physicians who are under no obligation to use them. Studies have shown that the systems are well received and that they help clinicians improve the quality of patient care. In addition, the CCC systems have had a beneficial impact on the finances of the two hospitals, and they have cost less than what many hospitals spend for financial computing alone.

An automatic frequency control loop using overlapping DFTs (Discrete Fourier Transforms)

NASA Technical Reports Server (NTRS)

Aguirre, S.

1988-01-01

An automatic frequency control (AFC) loop is introduced and analyzed in detail. The new scheme is a generalization of the well known Cross Product AFC loop that uses running overlapping discrete Fourier transforms (DFTs) to create a discriminator curve. Linear analysis is included and supported with computer simulations. The algorithm is tested in a low carrier to noise ratio (CNR) dynamic environment, and the probability of loss of lock is estimated via computer simulations. The algorithm discussed is a suboptimum tracking scheme with a larger frequency error variance compared to an optimum strategy, but offers simplicity of implementation and a very low operating threshold CNR. This technique can be applied during the carrier acquisition and re-acquisition process in the Advanced Receiver.

Method and apparatus for measuring solar radiation in a vegetative canopy

DOEpatents

Gutschick, V.P.; Barron, M.H.; Waechter, D.A.; Wolf, M.A.

1985-04-30

An apparatus and method for measuring solar radiation received in a vegetative canopy. A multiplicity of sensors selectively generates electrical signals in response to impinging photosynthetically active radiation in sunlight. Each sensor is attached to a plant within the canopy and is electrically connected to a separate port in a junction box having a multiplicity of ports. Each port is connected to an operational amplifier. Each amplifier amplifies the signals generated by the sensors. Each amplifier is connected to an analog-to-digital convertor which digitizes each signal. A computer is connected to the convertors and accumulates and stores solar radiation data. A data output device such as a printer is connected to the computer and displays the data.

Method and apparatus for measuring solar radiation in a vegetative canopy

DOEpatents

Gutschick, Vincent P.; Barron, Michael H.; Waechter, David A.; Wolf, Michael A.

1987-01-01

An apparatus and method for measuring solar radiation received in a vegetative canopy. A multiplicity of sensors selectively generates electrical signals in response to impinging photosynthetically active radiation in sunlight. Each sensor is attached to a plant within the canopy and is electrically connected to a separate port in a junction box having a multiplicity of ports. Each port is connected to an operational amplifier. Each amplifier amplifies the signals generated by the sensors. Each amplifier is connected to an analog-to-digital convertor which digitizes each signal. A computer is connected to the convertors and accumulates and stores solar radiation data. A data output device such as a printer is connected to the computer and displays the data.

Technology and design of an active-matrix OLED on crystalline silicon direct-view display for a wristwatch computer

NASA Astrophysics Data System (ADS)

Sanford, James L.; Schlig, Eugene S.; Prache, Olivier; Dove, Derek B.; Ali, Tariq A.; Howard, Webster E.

2002-02-01

The IBM Research Division and eMagin Corp. jointly have developed a low-power VGA direct view active matrix OLED display, fabricated on a crystalline silicon CMOS chip. The display is incorporated in IBM prototype wristwatch computers running the Linus operating system. IBM designed the silicon chip and eMagin developed the organic stack and performed the back-end-of line processing and packaging. Each pixel is driven by a constant current source controlled by a CMOS RAM cell, and the display receives its data from the processor memory bus. This paper describes the OLED technology and packaging, and outlines the design of the pixel and display electronics and the processor interface. Experimental results are presented.

Experimental Study on Ultrasonic Computed Tomography Using Transducers Arrayed on the Internal Surface of a Cylinder

NASA Astrophysics Data System (ADS)

Kim, Jung-Soon; Kim, Moo-Joon; Kim, Jung-Ho; Ha, Kang-Lyeol

2005-06-01

In this study, ultrasonic array transducers with 32 vibrators arranged on the internal surface of a part of a cylinder were fabricated. The vibrators were operated by the piezoelectric transverse effect. By controlling the phase of the input signal for every vibrator, a quasi plane wave was synthesized. Using the fabricated array, inverse scattering ultrasonic computed tomography (UCT) was carried out with a phantom specimen after checking the plane wave generation. It was confirmed that the plane wave was synthesized successfully and a sound velocity image of the phantom was obtained by the plane wave. Consequently, it was noted that the array could be employed as a transmitter and receiver for data acquisition in UCT.

Dose commitments due to radioactive releases from nuclear power plant sites: Methodology and data base. Supplement 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baker, D.A.

1996-06-01

This manual describes a dose assessment system used to estimate the population or collective dose commitments received via both airborne and waterborne pathways by persons living within a 2- to 80-kilometer region of a commercial operating power reactor for a specific year of effluent releases. Computer programs, data files, and utility routines are included which can be used in conjunction with an IBM or compatible personal computer to produce the required dose commitments and their statistical distributions. In addition, maximum individual airborne and waterborne dose commitments are estimated and compared to 10 CFR Part 50, Appendix 1, design objectives. Thismore » supplement is the last report in the NUREG/CR-2850 series.« less

Analysis of the Optimum Receiver Design Problem Using Interactive Computer Graphics.

DTIC Science & Technology

1981-12-01

7 _AD A115 498A l AR FORCE INST OF TECH WR16HT-PATTERSON AF8 OH SCHOO--ETC F/6 9/2 ANALYSIS OF THE OPTIMUM RECEIVER DESIGN PROBLEM USING INTERACTI...ANALYSIS OF THE OPTIMUM RECEIVER DESIGN PROBLEM USING INTERACTIVE COMPUTER GRAPHICS THESIS AFIT/GE/EE/81D-39 Michael R. Mazzuechi Cpt USA Approved for...public release; distribution unlimited AFIT/GE/EE/SlD-39 ANALYSIS OF THE OPTIMUM RECEIVER DESIGN PROBLEM USING INTERACTIVE COMPUTER GRAPHICS THESIS

48 CFR 552.216-73 - Ordering Information.

Code of Federal Regulations, 2010 CFR

2010-10-01

... transmission or □ computer-to-computer Electronic Data Interchange (EDI). (b) An offeror electing to receive computer-to-computer EDI is requested to indicate below the name, address, and telephone number of the representative to be contacted regarding establishment of an EDI interface. (c) An offeror electing to receive...

Improved Timing Scheme for Spaceborne Precipitation Radar

NASA Technical Reports Server (NTRS)

Berkun, Andrew; Fischman, Mark

2004-01-01

An improved timing scheme has been conceived for operation of a scanning satellite-borne rain-measuring radar system. The scheme allows a real-time-generated solution, which is required for auto targeting. The current timing scheme used in radar satellites involves pre-computing a solution that allows the instrument to catch all transmitted pulses without transmitting and receiving at the same time. Satellite altitude requires many pulses in flight at any time, and the timing solution to prevent transmit and receive operations from colliding is usually found iteratively. The proposed satellite has a large number of scanning beams each with a different range to target and few pulses per beam. Furthermore, the satellite will be self-targeting, so the selection of which beams are used will change from sweep to sweep. The proposed timing solution guarantees no echo collisions, can be generated using simple FPGA-based hardware in real time, and can be mathematically shown to deliver the maximum number of pulses per second, given the timing constraints. The timing solution is computed every sweep, and consists of three phases: (1) a build-up phase, (2) a feedback phase, and (3) a build-down phase. Before the build-up phase can begin, the beams to be transmitted are sorted in numerical order. The numerical order of the beams is also the order from shortest range to longest range. Sorting the list guarantees no pulse collisions. The build-up phase begins by transmitting the first pulse from the first beam on the list. Transmission of this pulse starts a delay counter, which stores the beam number and the time delay to the beginning of the receive window for that beam. The timing generator waits just long enough to complete the transmit pulse plus one receive window, then sends out the second pulse. The second pulse starts a second delay counter, which stores its beam number and time delay. This process continues until an output from the first timer indicates there is less than one transmit pulse width until the start of the next receive event. This blocks future transmit pulses in the build-up phase. The feedback phase begins with the first timer paying off and starting the first receive window. When the first receive window is complete, the timing generator transmits the next beam from the list. When the second timer pays off, the second receive event is started. Following the second receive event, the timing generator will transmit the next beam on the list and start an additional timer. The timers work in a circular buffer fashion so there only need to be enough to cover the maximum number of echoes in flight.

Battlefield casualties treated at Camp Rhino, Afghanistan: lessons learned.

PubMed

Bilski, Tracy R; Baker, Bruce C; Grove, Jay R; Hinks, Robert P; Harrison, Michael J; Sabra, John P; Temerlin, Steven M; Rhee, Peter

2003-05-01

Operation Enduring Freedom is an effort to combat terrorism after an attack on the United States. The first large-scale troop movement (> 1,300) was made by the U.S. Marines into the country of Afghanistan by establishing Camp Rhino. Data were entered into a personal computer at Camp Rhino, using combat casualty collecting software. Surgical support at Camp Rhino consisted of two surgical teams (12 personnel each), who set up two operating tables in one tent. During the 6-week period, a total of 46 casualties were treated, and all were a result of blast or blunt injury. One casualty required immediate surgery, two required thoracostomy tube, and the remainder received fracture stabilization or wound care before being transported out of Afghanistan. The casualties received 6 major surgical procedures and 11 minor procedures, which included fracture fixations. There was one killed in action and one expectant patient. The major problem faced was long delay in access to initial surgical care, which was more than 5 hours and 2 hours for two of the casualties. Smaller, more mobile surgical teams will be needed more frequently in future military operations because of inability to set up current larger surgical facilities, and major problems will include long transport times. Future improvements to the system should emphasize casualty evacuation, en-route care, and joint operations planning between services.

Initial data from a new High Spectral Resolution Lidar. Appendix A

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eloranta, E.W.; Piironen, P.K.

1993-12-31

The University of Wisconsin High Spectral Resolution Lidar (HSRL) has been recently redesigned for operation in an electronics semitrailer van. The HSRL can now be deployed in support of field experiments. This paper presents initial observations with the new configuration along with an analysis of measurement accuracy. New measurement capabilities have been added. These include: observation of the signal variation with angular field of view, and observation of depolarization in all data channels. Depolarization measurements have been implemented by transmitting orthogonal linear polarizations on alternate laser pulses. Pulses are transmitted at 250 {micro}s intervals such that the lidar observes themore » same ensemble of particles for both polarizations. Orthogonal polarizations are measured with a single detector per channel. Since the optical components and detector gains are identical for the two polarizations the measured depolarization ratios are independent of these factors and the system delivers very precise depolarizations. A new data channel with a computer controlled aperture allows measurements of multiple scattering as a function of receiver field of view. Since the field of view variation is dependent on the size of the scattering particles it is expected that this will allow remote measurements of cloud particle size. Other technical improvements in the new system include active control of spectrometer temperatures, greatly increased mechanical stability, an increased receiver aperture, injection of calibration signals into the signal profiles to allow continuous monitoring of system calibration drifts, and extensive computer control of system operations.« less

High-Performance Computing Systems and Operations | Computational Science |

Science.gov Websites

NREL Systems and Operations High-Performance Computing Systems and Operations NREL operates high-performance computing (HPC) systems dedicated to advancing energy efficiency and renewable energy technologies. Capabilities NREL's HPC capabilities include: High-Performance Computing Systems We operate

Spaceborne receivers: Basic principles

NASA Technical Reports Server (NTRS)

Stacey, J. M.

1984-01-01

The underlying principles of operation of microwave receivers for space observations of planetary surfaces were examined. The design philosophy of the receiver as it is applied to operate functionally as an efficient receiving system, the principle of operation of the key components of the receiver, and the important differences among receiver types are explained. The operating performance and the sensitivity expectations for both the modulated and total power receiver configurations are outlined. The expressions are derived from first principles and are developed through the important intermediate stages to form practicle and easily applied equations. The transfer of thermodynamic energy from point to point within the receiver is illustrated. The language of microwave receivers is applied statistics.

Image matrix processor for fast multi-dimensional computations

DOEpatents

Roberson, George P.; Skeate, Michael F.

1996-01-01

An apparatus for multi-dimensional computation which comprises a computation engine, including a plurality of processing modules. The processing modules are configured in parallel and compute respective contributions to a computed multi-dimensional image of respective two dimensional data sets. A high-speed, parallel access storage system is provided which stores the multi-dimensional data sets, and a switching circuit routes the data among the processing modules in the computation engine and the storage system. A data acquisition port receives the two dimensional data sets representing projections through an image, for reconstruction algorithms such as encountered in computerized tomography. The processing modules include a programmable local host, by which they may be configured to execute a plurality of different types of multi-dimensional algorithms. The processing modules thus include an image manipulation processor, which includes a source cache, a target cache, a coefficient table, and control software for executing image transformation routines using data in the source cache and the coefficient table and loading resulting data in the target cache. The local host processor operates to load the source cache with a two dimensional data set, loads the coefficient table, and transfers resulting data out of the target cache to the storage system, or to another destination.

Development of a remote control console for the HHIRF 25-MV tandem accelerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hasanul Basher, A.M.

1991-09-01

The CAMAC-based control system for the 25-MV Tandem Accelerator at HHIRF uses two Perkin-Elmer, 32-bit minicomputers: a message-switching computer and a supervisory computer. Two operator consoles are located on one of the six serial highways. Operator control is provided by means of a console CRT, trackball, assignable shaft encoders and meters. The message-switching computer transmits and receives control information on the serial highways. At present, the CRT pages with updated parameters can be displayed and parameters can be controlled only from the two existing consoles, one in the Tandem control room and the other in the ORIC control room. Itmore » has become necessary to expand the control capability to several other locations in the building. With the expansion of control and monitoring capability of accelerator parameters to other locations, the operators will be able to control and observe the result of the control action at the same time. Since the new control console will be PC-based, the existing page format will be changed. The PC will be communicating with the Perkin-Elmer through RS-232 and a communication software package. Hardware configuration has been established, a communication software program that reads the pages from the shared memory has been developed. In this paper, we present the implementation strategy, works completed, existing and new page format, future action plans, explanation of pages and use of related global variables, a sample session, and flowcharts.« less

A remote control console for the HHIRF 25-MV Tandem Accelerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hasanul Basher, A.M.

The CAMAC-based control system for the 25-MV Tandem Accelerator at HHIRF uses two Perkin-Elmer, 32-bit minicomputers: a message-switching computer and a supervisory computer. Two operator consoles are located on one of the six serial highways. Operator control is provided by means of a console CRT, trackball, assignable shaft encoders, and meters. The message-switching computer transmits and receives control information on the serial highways. At present, the CRT pages with updated parameters can be displayed and parameters can be controlled only from the two existing consoles, one in the Tandem control room and the other in the ORIC control room. Itmore » has become necessary to expand the control capability to several other locations in the building. With the expansion of control and monitoring capability of accelerator parameters to other locations, the operators will be able to control and observe the result of the control action at the same time. This capability will be useful in the new Radioactive Ion Beam project of the division. Since the new control console will be PC-based, the existing page format will be changed. The PC will be communicating with the Perkin-Elmer through RS-232 with the aid of a communication protocol. Hardware configuration has been established, a software program that reads the pages from the shared memory, and a communication protocol have been developed. The following sections present the implementation strategy, work completed, future action plans, and the functional details of the communication protocol.« less

Verification of Meteorological and Oceanographic Ensemble Forecasts in the U.S. Navy

NASA Astrophysics Data System (ADS)

Klotz, S.; Hansen, J.; Pauley, P.; Sestak, M.; Wittmann, P.; Skupniewicz, C.; Nelson, G.

2013-12-01

The Navy Ensemble Forecast Verification System (NEFVS) has been promoted recently to operational status at the U.S. Navy's Fleet Numerical Meteorology and Oceanography Center (FNMOC). NEFVS processes FNMOC and National Centers for Environmental Prediction (NCEP) meteorological and ocean wave ensemble forecasts, gridded forecast analyses, and innovation (observational) data output by FNMOC's data assimilation system. The NEFVS framework consists of statistical analysis routines, a variety of pre- and post-processing scripts to manage data and plot verification metrics, and a master script to control application workflow. NEFVS computes metrics that include forecast bias, mean-squared error, conditional error, conditional rank probability score, and Brier score. The system also generates reliability and Receiver Operating Characteristic diagrams. In this presentation we describe the operational framework of NEFVS and show examples of verification products computed from ensemble forecasts, meteorological observations, and forecast analyses. The construction and deployment of NEFVS addresses important operational and scientific requirements within Navy Meteorology and Oceanography. These include computational capabilities for assessing the reliability and accuracy of meteorological and ocean wave forecasts in an operational environment, for quantifying effects of changes and potential improvements to the Navy's forecast models, and for comparing the skill of forecasts from different forecast systems. NEFVS also supports the Navy's collaboration with the U.S. Air Force, NCEP, and Environment Canada in the North American Ensemble Forecast System (NAEFS) project and with the Air Force and the National Oceanic and Atmospheric Administration (NOAA) in the National Unified Operational Prediction Capability (NUOPC) program. This program is tasked with eliminating unnecessary duplication within the three agencies, accelerating the transition of new technology, such as multi-model ensemble forecasting, to U.S. Department of Defense use, and creating a superior U.S. global meteorological and oceanographic prediction capability. Forecast verification is an important component of NAEFS and NUOPC. Distribution Statement A: Approved for Public Release; distribution is unlimited

Verification of Meteorological and Oceanographic Ensemble Forecasts in the U.S. Navy

NASA Astrophysics Data System (ADS)

Klotz, S. P.; Hansen, J.; Pauley, P.; Sestak, M.; Wittmann, P.; Skupniewicz, C.; Nelson, G.

2012-12-01

The Navy Ensemble Forecast Verification System (NEFVS) has been promoted recently to operational status at the U.S. Navy's Fleet Numerical Meteorology and Oceanography Center (FNMOC). NEFVS processes FNMOC and National Centers for Environmental Prediction (NCEP) meteorological and ocean wave ensemble forecasts, gridded forecast analyses, and innovation (observational) data output by FNMOC's data assimilation system. The NEFVS framework consists of statistical analysis routines, a variety of pre- and post-processing scripts to manage data and plot verification metrics, and a master script to control application workflow. NEFVS computes metrics that include forecast bias, mean-squared error, conditional error, conditional rank probability score, and Brier score. The system also generates reliability and Receiver Operating Characteristic diagrams. In this presentation we describe the operational framework of NEFVS and show examples of verification products computed from ensemble forecasts, meteorological observations, and forecast analyses. The construction and deployment of NEFVS addresses important operational and scientific requirements within Navy Meteorology and Oceanography (METOC). These include computational capabilities for assessing the reliability and accuracy of meteorological and ocean wave forecasts in an operational environment, for quantifying effects of changes and potential improvements to the Navy's forecast models, and for comparing the skill of forecasts from different forecast systems. NEFVS also supports the Navy's collaboration with the U.S. Air Force, NCEP, and Environment Canada in the North American Ensemble Forecast System (NAEFS) project and with the Air Force and the National Oceanic and Atmospheric Administration (NOAA) in the National Unified Operational Prediction Capability (NUOPC) program. This program is tasked with eliminating unnecessary duplication within the three agencies, accelerating the transition of new technology, such as multi-model ensemble forecasting, to U.S. Department of Defense use, and creating a superior U.S. global meteorological and oceanographic prediction capability. Forecast verification is an important component of NAEFS and NUOPC.

Computer algebra and operators

NASA Technical Reports Server (NTRS)

Fateman, Richard; Grossman, Robert

1989-01-01

The symbolic computation of operator expansions is discussed. Some of the capabilities that prove useful when performing computer algebra computations involving operators are considered. These capabilities may be broadly divided into three areas: the algebraic manipulation of expressions from the algebra generated by operators; the algebraic manipulation of the actions of the operators upon other mathematical objects; and the development of appropriate normal forms and simplification algorithms for operators and their actions. Brief descriptions are given of the computer algebra computations that arise when working with various operators and their actions.

High Temperature Shear Horizontal Electromagnetic Acoustic Transducer for Guided Wave Inspection

PubMed Central

Kogia, Maria; Gan, Tat-Hean; Balachandran, Wamadeva; Livadas, Makis; Kappatos, Vassilios; Szabo, Istvan; Mohimi, Abbas; Round, Andrew

2016-01-01

Guided Wave Testing (GWT) using novel Electromagnetic Acoustic Transducers (EMATs) is proposed for the inspection of large structures operating at high temperatures. To date, high temperature EMATs have been developed only for thickness measurements and they are not suitable for GWT. A pair of water-cooled EMATs capable of exciting and receiving Shear Horizontal (SH0) waves for GWT with optimal high temperature properties (up to 500 °C) has been developed. Thermal and Computational Fluid Dynamic (CFD) simulations of the EMAT design have been performed and experimentally validated. The optimal thermal EMAT design, material selection and operating conditions were calculated. The EMAT was successfully tested regarding its thermal and GWT performance from ambient temperature to 500 °C. PMID:27110792

Remote Control and Monitoring of VLBI Experiments by Smartphones

NASA Astrophysics Data System (ADS)

Ruztort, C. H.; Hase, H.; Zapata, O.; Pedreros, F.

2012-12-01

For the remote control and monitoring of VLBI operations, we developed a software optimized for smartphones. This is a new tool based on a client-server architecture with a Web interface optimized for smartphone screens and cellphone networks. The server uses variables of the Field System and its station specific parameters stored in the shared memory. The client running on the smartphone by a Web interface analyzes and visualizes the current status of the radio telescope, receiver, schedule, and recorder. In addition, it allows commands to be sent remotely to the Field System computer and displays the log entries. The user has full access to the entire operation process, which is important in emergency cases. The software also integrates a webcam interface.

Development of a platform-independent receiver control system for SISIFOS

NASA Astrophysics Data System (ADS)

Lemke, Roland; Olberg, Michael

1998-05-01

Up to now receiver control software was a time consuming development usually written by receiver engineers who had mainly the hardware in mind. We are presenting a low-cost and very flexible system which uses a minimal interface to the real hardware, and which makes it easy to adapt to new receivers. Our system uses Tcl/Tk as a graphical user interface (GUI), SpecTcl as a GUI builder, Pgplot as plotting software, a simple query language (SQL) database for information storage and retrieval, Ethernet socket to socket communication and SCPI as a command control language. The complete system is in principal platform independent but for cost saving reasons we are using it actually on a PC486 running Linux 2.0.30, which is a copylefted Unix. The only hardware dependent part are the digital input/output boards, analog to digital and digital to analog convertors. In the case of the Linux PC we are using a device driver development kit to integrate the boards fully into the kernel of the operating system, which indeed makes them look like an ordinary device. The advantage of this system is firstly the low price and secondly the clear separation between the different software components which are available for many operating systems. If it is not possible, due to CPU performance limitations, to run all the software in a single machine,the SQL-database or the graphical user interface could be installed on separate computers.

Solar thermochemical processing system and method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wegeng, Robert S.; Humble, Paul H.; Krishnan, Shankar

A solar thermochemical processing system is disclosed. The system includes a first unit operation for receiving concentrated solar energy. Heat from the solar energy is used to drive the first unit operation. The first unit operation also receives a first set of reactants and produces a first set of products. A second unit operation receives the first set of products from the first unit operation and produces a second set of products. A third unit operation receives heat from the second unit operation to produce a portion of the first set of reactants.

The Crustal Structure of the Central Anatolia (Turkey) Using Receiver Functions

NASA Astrophysics Data System (ADS)

Yelkenci, S.; Benoit, M.; Kuleli, H.; Gurbuz, C.

2005-12-01

Central Anatolia lies in a transitional region between the extensional tectonics of western Anatolia and the complex transpressional tectonics of Eastern Anatolia, and has a complicated thermal and structural history. Few studies of the crustal structure of Anatolia have been performed, however, studies of the crustal structure of Eastern Anatolia showed that crustal thicknesses were thinner than previously thought. To further investigate the crustal structure in Central Anatolia, we present results from receiver function analysis using new data from broad-band instruments. The stations were equipped with 7 broadband three-component STS-2 and 13 short period three-component S-13 sensors. These stations operated for period of one and half months between the October and November, 2002, and yielded data for ~ 40 high quality receiver functions. Additionally, receiver functions were also computed using data from permanent stations MALT, ISP, and ANTO. We applied the hk-stacking technique of Zhu and Kanamori (2000) to receiver functions to obtain the crustal thickness and Vp/Vs ratios. Furthermore, we applied a waveform modeling technique to investigate mid-crustal discontinuties previously imaged in the region. Our results compare well with refraction-based crustal thicknesses in overlapped areas.

Distributed processing of a GPS receiver network for a regional ionosphere map

NASA Astrophysics Data System (ADS)

Choi, Kwang Ho; Hoo Lim, Joon; Yoo, Won Jae; Lee, Hyung Keun

2018-01-01

This paper proposes a distributed processing method applicable to GPS receivers in a network to generate a regional ionosphere map accurately and reliably. For accuracy, the proposed method is operated by multiple local Kalman filters and Kriging estimators. Each local Kalman filter is applied to a dual-frequency receiver to estimate the receiver’s differential code bias and vertical ionospheric delays (VIDs) at different ionospheric pierce points. The Kriging estimator selects and combines several VID estimates provided by the local Kalman filters to generate the VID estimate at each ionospheric grid point. For reliability, the proposed method uses receiver fault detectors and satellite fault detectors. Each receiver fault detector compares the VID estimates of the same local area provided by different local Kalman filters. Each satellite fault detector compares the VID estimate of each local area with that projected from the other local areas. Compared with the traditional centralized processing method, the proposed method is advantageous in that it considerably reduces the computational burden of each single Kalman filter and enables flexible fault detection, isolation, and reconfiguration capability. To evaluate the performance of the proposed method, several experiments with field collected measurements were performed.

Design requirements, challenges, and solutions for high-temperature falling particle receivers

NASA Astrophysics Data System (ADS)

Christian, Joshua; Ho, Clifford

2016-05-01

Falling particle receivers (FPR) utilize small particles as a heat collecting medium within a cavity receiver structure. Previous analysis for FPR systems include computational fluid dynamics (CFD), analytical evaluations, and experiments to determine the feasibility and achievability of this CSP technology. Sandia National Laboratories has fabricated and tested a 1 MWth FPR that consists of a cavity receiver, top hopper, bottom hopper, support structure, particle elevator, flux target, and instrumentation. Design requirements and inherent challenges were addressed to enable continuous operation of flowing particles under high-flux conditions and particle temperatures over 700 °C. Challenges include being able to withstand extremely high temperatures (up to 1200°C on the walls of the cavity), maintaining particle flow and conveyance, measuring temperatures and mass flow rates, filtering out debris, protecting components from direct flux spillage, and measuring irradiance in the cavity. Each of the major components of the system is separated into design requirements, associated challenges and corresponding solutions. The intent is to provide industry and researchers with lessons learned to avoid pitfalls and technical problems encountered during the development of Sandia's prototype particle receiver system at the National Solar Thermal Test Facility (NSTTF).

Performance evaluation of 4 measuring methods of ground-glass opacities for predicting the 5-year relapse-free survival of patients with peripheral nonsmall cell lung cancer: a multicenter study.

PubMed

Kakinuma, Ryutaro; Kodama, Ken; Yamada, Kouzo; Yokoyama, Akira; Adachi, Shuji; Mori, Kiyoshi; Fukuyama, Yasuro; Fukuda, Yasuro; Kuriyama, Keiko; Oda, Junichi; Oda, Junji; Noguchi, Masayuki; Matsuno, Yoshihiro; Yokose, Tomoyuki; Ohmatsu, Hironobu; Nishiwaki, Yutaka

2008-01-01

To evaluate the performance of 4 methods of measuring the extent of ground-glass opacities as a means of predicting the 5-year relapse-free survival of patients with peripheral nonsmall cell lung cancer (NSLC). Ground-glass opacities on thin-section computed tomographic images of 120 peripheral NSLCs were measured at 7 medical institutions by the length, area, modified length, and vanishing ratio (VR) methods. The performance (Az) of each method in predicting the 5-year relapse-free survival was evaluated using receiver operating characteristic analysis. The mean Az value obtained by the length, area, modified length, and VR methods in the receiver operating characteristic analyses was 0.683, 0.702, 0.728, and 0.784, respectively. The differences between the mean Az value obtained by the VR method and by the other 3 methods were significant. Vanishing ratio method was the most accurate predictor of the 5-year relapse-free survival of patients with peripheral NSLC.

Flight Test Results from Real-Time Relative Global Positioning System Flight Experiment on STS-69

NASA Technical Reports Server (NTRS)

Park, Young W.; Brazzel, Jack P., Jr.; Carpenter, J. Russell; Hinkel, Heather D.; Newman, James H.

1996-01-01

A real-time global positioning system (GPS) Kalman filter has been developed to support automated rendezvous with the International Space Station (ISS). The filter is integrated with existing Shuttle rendezvous software running on a 486 laptop computer under Windows. In this work, we present real-time and postflight results achieved with the filter on STS-69. The experiment used GPS data from an Osborne/Jet propulsion Laboratory TurboRouge receiver carried on the Wake Shield Facility (WSF) free flyer and a Rockwell Collins 3M receiver carried on the Orbiter. Real time filter results, processed onboard the Shuttle and replayed in near-time on the ground, are based on single vehicle mode operation and on 5 to 20 minute snapshots of telemetry provided by WSF for dual-vehicle mode operation. The Orbiter and WSF state vectors calculated using our filter compare favorably with precise reference orbits determined by the University of Texas Center for Space Research. The lessons learned from this experiment will be used in conjunction with future experiments to mitigate the technology risk posed by automated rendezvous and docking to the ISS.

Training Teachers to Use Computers: A Case Study of the Summer Training Component of the IBM/ETS Secondary School Computer Education Program. Research Report.

ERIC Educational Resources Information Center

Stecher, Brian

A training program in computer educationtTested in 89 secondary schools focused on the use of computers as tools in all subject areas. Each school received enough computers and software from IBM to equip a full computer laboratory. The schools were organized into local networks in eight regions and received training and continuing support in these…

Automatically-computed prehospital severity scores are equivalent to scores based on medic documentation.

PubMed

Reisner, Andrew T; Chen, Liangyou; McKenna, Thomas M; Reifman, Jaques

2008-10-01

Prehospital severity scores can be used in routine prehospital care, mass casualty care, and military triage. If computers could reliably calculate clinical scores, new clinical and research methodologies would be possible. One obstacle is that vital signs measured automatically can be unreliable. We hypothesized that Signal Quality Indices (SQI's), computer algorithms that differentiate between reliable and unreliable monitored physiologic data, could improve the predictive power of computer-calculated scores. In a retrospective analysis of trauma casualties transported by air ambulance, we computed the Triage Revised Trauma Score (RTS) from archived travel monitor data. We compared the areas-under-the-curve (AUC's) of receiver operating characteristic curves for prediction of mortality and red blood cell transfusion for 187 subjects with comparable quantities of good-quality and poor-quality data. Vital signs deemed reliable by SQI's led to significantly more discriminatory severity scores than vital signs deemed unreliable. We also compared automatically-computed RTS (using the SQI's) versus RTS computed from vital signs documented by medics. For the subjects in whom the SQI algorithms identified 15 consecutive seconds of reliable vital signs data (n = 350), the automatically-computed scores' AUC's were the same as the medic-based scores' AUC's. Using the Prehospital Index in place of RTS led to very similar results, corroborating our findings. SQI algorithms improve automatically-computed severity scores, and automatically-computed scores using SQI's are equivalent to medic-based scores.

Evaluation of remote hydrologic data-acquisition systems, west-central Florida

USGS Publications Warehouse

Turner, J.F.; Woodham, W.M.

1980-01-01

The study provides an evaluation of the hydrologic applications of a land-line and two satellite data-relay systems operated during 1977-78 in the Southwest Florida Water Management District. These systems were tested to evaluate operational and reliability characteristics. Telephone lines were used to relay data in the land-line system, and the Geostationary Operational Environmental Satellite (GOES) and Land satellite (Landsat) were used in the satellite system. The land-line system was tested for 15 months at a streamflow site. Accurate data were obtained 94% of the time during the test period. Data losses were attributed to telephone-line interference, low-battery voltage, and vandalism. The GOES system was tested at a rainfall site for 17 months. During this period, 79% of the transmissions received from the station were relayed by the GOES system to the U.S. Geological Survey computer, resulting in successful processing of 88% of all possible rainfall observations. On the average, seven data transmissions were completed each day. The Landsat system was tested at a rainfall site for about 17 months and for about 8 months at a streamflow site. During these periods of operation, only about 2% of all data observations for the stations were successfully relayed by the Landsat system to the U.S. Geological Survey computer. An average of about three data transmissions was completed each day for each site. (USGS).

Computer-associated health complaints and sources of ergonomic instructions in computer-related issues among Finnish adolescents: a cross-sectional study.

PubMed

Hakala, Paula T; Saarni, Lea A; Ketola, Ritva L; Rahkola, Erja T; Salminen, Jouko J; Rimpelä, Arja H

2010-01-11

The use of computers has increased among adolescents, as have musculoskeletal symptoms. There is evidence that these symptoms can be reduced through an ergonomics approach and through education. The purpose of this study was to examine where adolescents had received ergonomic instructions related to computer use, and whether receiving these instructions was associated with a reduced prevalence of computer-associated health complaints. Mailed survey with nationally representative sample of 12 to 18-year-old Finns in 2001 (n = 7292, response rate 70%). In total, 6961 youths reported using a computer. We tested the associations of computer use time and received ergonomic instructions (predictor variables) with computer-associated health complaints (outcome variables) using logistic regression analysis. To prevent computer-associated complaints, 61.2% reported having been instructed to arrange their desk/chair/screen in the right position, 71.5% to take rest breaks. The older age group (16-18 years) reported receiving instructions or being self-instructed more often than the 12- to 14-year-olds (p < 0.001). Among both age groups the sources of instructions included school (33.1%), family (28.6%), self (self-instructed) (12.5%), ICT-related (8.6%), friends (1.5%) and health professionals (0.8%). Receiving instructions was not related to lower prevalence of computer-associated health complaints. This report shows that ergonomic instructions on how to prevent computer-related musculoskeletal problems fail to reach a substantial number of children. Furthermore, the reported sources of instructions vary greatly in terms of reliability.

Computer-associated health complaints and sources of ergonomic instructions in computer-related issues among Finnish adolescents: A cross-sectional study

PubMed Central

2010-01-01

Background The use of computers has increased among adolescents, as have musculoskeletal symptoms. There is evidence that these symptoms can be reduced through an ergonomics approach and through education. The purpose of this study was to examine where adolescents had received ergonomic instructions related to computer use, and whether receiving these instructions was associated with a reduced prevalence of computer-associated health complaints. Methods Mailed survey with nationally representative sample of 12 to 18-year-old Finns in 2001 (n = 7292, response rate 70%). In total, 6961 youths reported using a computer. We tested the associations of computer use time and received ergonomic instructions (predictor variables) with computer-associated health complaints (outcome variables) using logistic regression analysis. Results To prevent computer-associated complaints, 61.2% reported having been instructed to arrange their desk/chair/screen in the right position, 71.5% to take rest breaks. The older age group (16-18 years) reported receiving instructions or being self-instructed more often than the 12- to 14-year-olds (p < 0.001). Among both age groups the sources of instructions included school (33.1%), family (28.6%), self (self-instructed) (12.5%), ICT-related (8.6%), friends (1.5%) and health professionals (0.8%). Receiving instructions was not related to lower prevalence of computer-associated health complaints. Conclusions This report shows that ergonomic instructions on how to prevent computer-related musculoskeletal problems fail to reach a substantial number of children. Furthermore, the reported sources of instructions vary greatly in terms of reliability. PMID:20064250

Efficient Irregular Wavefront Propagation Algorithms on Hybrid CPU-GPU Machines

PubMed Central

Teodoro, George; Pan, Tony; Kurc, Tahsin; Kong, Jun; Cooper, Lee; Saltz, Joel

2013-01-01

We address the problem of efficient execution of a computation pattern, referred to here as the irregular wavefront propagation pattern (IWPP), on hybrid systems with multiple CPUs and GPUs. The IWPP is common in several image processing operations. In the IWPP, data elements in the wavefront propagate waves to their neighboring elements on a grid if a propagation condition is satisfied. Elements receiving the propagated waves become part of the wavefront. This pattern results in irregular data accesses and computations. We develop and evaluate strategies for efficient computation and propagation of wavefronts using a multi-level queue structure. This queue structure improves the utilization of fast memories in a GPU and reduces synchronization overheads. We also develop a tile-based parallelization strategy to support execution on multiple CPUs and GPUs. We evaluate our approaches on a state-of-the-art GPU accelerated machine (equipped with 3 GPUs and 2 multicore CPUs) using the IWPP implementations of two widely used image processing operations: morphological reconstruction and euclidean distance transform. Our results show significant performance improvements on GPUs. The use of multiple CPUs and GPUs cooperatively attains speedups of 50× and 85× with respect to single core CPU executions for morphological reconstruction and euclidean distance transform, respectively. PMID:23908562

Computationally robust and noise resistant numerical detector for the detection of atmospheric infrasound.

PubMed

Lee, Dong-Chang; Olson, John V; Szuberla, Curt A L

2013-07-01

This work reports on a performance study of two numerical detectors that are particularly useful for infrasound arrays operating under windy conditions. The sum of squares of variance ratios (SSVR1)-proposed for detecting signals with frequency ranging from 1 to 10 Hz-is computed by taking the ratio of the squared sum of eigenvalues to the square of largest eigenvalue of the covariance matrix of the power spectrum. For signals with lower frequency between 0.015 and 0.1 Hz, SSVR2 is developed to reduce the detector's sensitivity to noise. The detectors' performances are graphically compared against the current method, the mean of cross correlation maxima (MCCM), using the receiver operating characteristics curves and three types of atmospheric infrasound, corrupted by Gaussian and Pink noise. The MCCM and SSVR2 detectors were also used to detect microbaroms from the 24 h-long infrasound data. It was found that the two detectors outperform the MCCM detector in both sensitivity and computational efficiency. For mine blasts corrupted by Pink noise (signal-to-noise ratio = -7 dB), the MCCM and SSVR1 detectors yield 62 and 88 % true positives when accepting 20% false positives. For an eight-sensor array, the speed gain is approximately eleven-fold for a 50 s long signal.

Abdominal injuries in a low trauma volume hospital - a descriptive study from northern Sweden

PubMed Central

2014-01-01

Background Abdominal injuries occur relatively infrequently during trauma, and they rarely require surgical intervention. In this era of non-operative management of abdominal injuries, surgeons are seldom exposed to these patients. Consequently, surgeons may misinterpret the mechanism of injury, underestimate symptoms and radiologic findings, and delay definite treatment. Here, we determined the incidence, diagnosis, and treatment of traumatic abdominal injuries at our hospital to provide a basis for identifying potential hazards in non-operative management of patients with these injuries in a low trauma volume hospital. Methods This retrospective study included prehospital and in-hospital assessments of 110 patients that received 147 abdominal injuries from an isolated abdominal trauma (n = 70 patients) or during multiple trauma (n = 40 patients). Patients were primarily treated at the University Hospital of Umeå from January 2000 to December 2009. Results The median New Injury Severity Score was 9 (range: 1–57) for 147 abdominal injuries. Most patients (94%) received computed tomography (CT), but only 38% of patients with multiple trauma were diagnosed with CT < 60 min after emergency room arrival. Penetrating trauma caused injuries in seven patients. Solid organ injuries constituted 78% of abdominal injuries. Non-operative management succeeded in 82 patients. Surgery was performed for 28 patients, either immediately (n = 17) as result of operative management or later (n = 11), due to non-operative management failure; the latter mainly occurred with hollow viscus injuries. Patients with multiple abdominal injuries, whether associated with multiple trauma or an isolated abdominal trauma, had significantly more non-operative failures than patients with a single abdominal injury. One death occurred within 30 days. Conclusions Non-operative management of patients with abdominal injuries, except for hollow viscus injuries, was highly successful in our low trauma volume hospital, even though surgeons receive low exposure to these patients. However, a growing proportion of surgeons lack experience in decision-making and performing trauma laparotomies. Quality assurance programmes must be emphasized to ensure future competence and quality of trauma care at low trauma volume hospitals. PMID:25124882

38 CFR 3.271 - Computation of income.

Code of Federal Regulations, 2012 CFR

2012-07-01

... income. Recurring income means income which is received or anticipated in equal amounts and at regular... computation purposes. (2) Irregular income. Irregular income means income which is received or anticipated during a 12-month annualization period, but which is received in unequal amounts or at irregular...

Broadcasting collective operation contributions throughout a parallel computer

DOEpatents

Faraj, Ahmad [Rochester, MN

2012-02-21

Methods, systems, and products are disclosed for broadcasting collective operation contributions throughout a parallel computer. The parallel computer includes a plurality of compute nodes connected together through a data communications network. Each compute node has a plurality of processors for use in collective parallel operations on the parallel computer. Broadcasting collective operation contributions throughout a parallel computer according to embodiments of the present invention includes: transmitting, by each processor on each compute node, that processor's collective operation contribution to the other processors on that compute node using intra-node communications; and transmitting on a designated network link, by each processor on each compute node according to a serial processor transmission sequence, that processor's collective operation contribution to the other processors on the other compute nodes using inter-node communications.

Improving diagnostic recognition of primary hyperparathyroidism with machine learning.

PubMed

Somnay, Yash R; Craven, Mark; McCoy, Kelly L; Carty, Sally E; Wang, Tracy S; Greenberg, Caprice C; Schneider, David F

2017-04-01

Parathyroidectomy offers the only cure for primary hyperparathyroidism, but today only 50% of primary hyperparathyroidism patients are referred for operation, in large part, because the condition is widely under-recognized. The diagnosis of primary hyperparathyroidism can be especially challenging with mild biochemical indices. Machine learning is a collection of methods in which computers build predictive algorithms based on labeled examples. With the aim of facilitating diagnosis, we tested the ability of machine learning to distinguish primary hyperparathyroidism from normal physiology using clinical and laboratory data. This retrospective cohort study used a labeled training set and 10-fold cross-validation to evaluate accuracy of the algorithm. Measures of accuracy included area under the receiver operating characteristic curve, precision (sensitivity), and positive and negative predictive value. Several different algorithms and ensembles of algorithms were tested using the Weka platform. Among 11,830 patients managed operatively at 3 high-volume endocrine surgery programs from March 2001 to August 2013, 6,777 underwent parathyroidectomy for confirmed primary hyperparathyroidism, and 5,053 control patients without primary hyperparathyroidism underwent thyroidectomy. Test-set accuracies for machine learning models were determined using 10-fold cross-validation. Age, sex, and serum levels of preoperative calcium, phosphate, parathyroid hormone, vitamin D, and creatinine were defined as potential predictors of primary hyperparathyroidism. Mild primary hyperparathyroidism was defined as primary hyperparathyroidism with normal preoperative calcium or parathyroid hormone levels. After testing a variety of machine learning algorithms, Bayesian network models proved most accurate, classifying correctly 95.2% of all primary hyperparathyroidism patients (area under receiver operating characteristic = 0.989). Omitting parathyroid hormone from the model did not decrease the accuracy significantly (area under receiver operating characteristic = 0.985). In mild disease cases, however, the Bayesian network model classified correctly 71.1% of patients with normal calcium and 92.1% with normal parathyroid hormone levels preoperatively. Bayesian networking and AdaBoost improved the accuracy of all parathyroid hormone patients to 97.2% cases (area under receiver operating characteristic = 0.994), and 91.9% of primary hyperparathyroidism patients with mild disease. This was significantly improved relative to Bayesian networking alone (P < .0001). Machine learning can diagnose accurately primary hyperparathyroidism without human input even in mild disease. Incorporation of this tool into electronic medical record systems may aid in recognition of this under-diagnosed disorder. Copyright © 2016 Elsevier Inc. All rights reserved.

ROC Analysis of Chest Radiographs Using Computed Radiography and Conventional Analog Films

NASA Astrophysics Data System (ADS)

Morioka, Craig A.; Brown, Kathy; Hayrapetian, Alek S.; Kangarloo, Hooshang; Balter, Stephen; Huang, H. K.

1989-05-01

Receiver operating characteristic is used to compare the image quality of films obtained digitally using computed radiography (CR) and conventionally using analog film following fluoroscopic examination. Similar radiological views were obtained by both modalities. Twenty-four cases, some with a solitary noncalcified nodule and/or pneumothorax, were collected. Ten radiologists have been tested viewing analog and CR digital films separately. Final results indicate that there is no statistically significant difference in the ability to detect either a pneumothorax or a solitary noncalcified nodule when comparing CR digital film with conventional analog film. However, there is a trend that indicated the area under the ROC curves for detection of either a pneumothorax or solitary noncalcified nodule were greater for the analog film than for the digital film.

Third Generation Wireless Phone Threat Assessment for Aircraft Communication and Navigation Radios

NASA Technical Reports Server (NTRS)

Nguyen, Truong X.; Koppen, Sandra V.; Smith, Laura J.; Williams, Reuben A.; Salud, Maria Theresa P.

2005-01-01

Radiated emissions in aircraft communication and navigation bands are measured from third generation (3G) wireless mobile phones. The two wireless technologies considered are the latest available to general consumers in the US. The measurements are conducted using reverberation chambers. The results are compared against baseline emissions from laptop computers and personal digital assistant devices that are currently allowed to operate on aircraft. Using existing interference path loss data and receivers interference threshold, a risk assessment is performed for several aircraft communication and navigation radio systems. In addition, cumulative interference effects of multiple similar devices are conservatively estimated or bounded. The effects are computed by summing the interference power from individual devices that is scaled according to the interference path loss at its location.

Adaptable radiation monitoring system and method

DOEpatents

Archer, Daniel E [Livermore, CA; Beauchamp, Brock R [San Ramon, CA; Mauger, G Joseph [Livermore, CA; Nelson, Karl E [Livermore, CA; Mercer, Michael B [Manteca, CA; Pletcher, David C [Sacramento, CA; Riot, Vincent J [Berkeley, CA; Schek, James L [Tracy, CA; Knapp, David A [Livermore, CA

2006-06-20

A portable radioactive-material detection system capable of detecting radioactive sources moving at high speeds. The system has at least one radiation detector capable of detecting gamma-radiation and coupled to an MCA capable of collecting spectral data in very small time bins of less than about 150 msec. A computer processor is connected to the MCA for determining from the spectral data if a triggering event has occurred. Spectral data is stored on a data storage device, and a power source supplies power to the detection system. Various configurations of the detection system may be adaptably arranged for various radiation detection scenarios. In a preferred embodiment, the computer processor operates as a server which receives spectral data from other networked detection systems, and communicates the collected data to a central data reporting system.

Quantum communication using a multiqubit entangled channel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghose, Shohini, E-mail: sghose@wlu.ca; Institute for Quantum Computing, University of Waterloo, Ontario; Hamel, Angele

We describe a protocol in which two senders each teleport a qubit to a receiver using a multiqubit entangled state. The multiqubit channel used for teleportation is genuinely 4-qubit entangled and is not equivalent to a product of maximally entangled Bell pairs under local unitary operations. We discuss a scenario in which both senders must participate for the qubits to be successfully teleported. Such an all-or-nothing scheme cannot be implemented with standard two-qubit entangled Bell pairs and can be useful for different communication and computing tasks.

System of Programmed Modules for Measuring Photographs with a Gamma-Telescope

NASA Technical Reports Server (NTRS)

Averin, S. A.; Veselova, G. V.; Navasardyan, G. V.

1978-01-01

Physical experiments using tracking cameras resulted in hundreds of thousands of stereo photographs of events being received. To process such a large volume of information, automatic and semiautomatic measuring systems are required. At the Institute of Space Research of the Academy of Science of the USSR, a system for processing film information from the spark gamma-telescope was developed. The system is based on a BPS-75 projector in line with the minicomputer Elektronika 1001. The report describes this system. The various computer programs available to the operators are discussed.

Quantum communication using a multiqubit entangled channel

NASA Astrophysics Data System (ADS)

Ghose, Shohini; Hamel, Angele

2015-12-01

We describe a protocol in which two senders each teleport a qubit to a receiver using a multiqubit entangled state. The multiqubit channel used for teleportation is genuinely 4-qubit entangled and is not equivalent to a product of maximally entangled Bell pairs under local unitary operations. We discuss a scenario in which both senders must participate for the qubits to be successfully teleported. Such an all-or-nothing scheme cannot be implemented with standard two-qubit entangled Bell pairs and can be useful for different communication and computing tasks.

The Alaska SAR processor - Operations and control

NASA Technical Reports Server (NTRS)

Carande, Richard E.

1989-01-01

The Alaska SAR (synthetic-aperture radar) Facility (ASF) will be capable of receiving, processing, archiving, and producing a variety of SAR image products from three satellite-borne SARs: E-ERS-1 (ESA), J-ERS-1 (NASDA) and Radarsat (Canada). Crucial to the success of the ASF is the Alaska SAR processor (ASP), which will be capable of processing over 200 100-km x 100-km (Seasat-like) frames per day from the raw SAR data, at a ground resolution of about 30 m x 30 m. The processed imagery is of high geometric and radiometric accuracy, and is geolocated to within 500 m. Special-purpose hardware has been designed to execute a SAR processing algorithm to achieve this performance. This hardware is currently undergoing acceptance testing for delivery to the University of Alaska. Particular attention has been devoted to making the operations semi-automated and to providing a friendly operator interface via a computer workstation. The operations and control of the Alaska SAR processor are described.

The use of interactive computer vision and robot hand controllers for enhancing manufacturing safety

NASA Technical Reports Server (NTRS)

Marzwell, Neville I.; Jacobus, Charles J.; Peurach, Thomas M.; Mitchell, Brian T.

1994-01-01

Current available robotic systems provide limited support for CAD-based model-driven visualization, sensing algorithm development and integration, and automated graphical planning systems. This paper describes ongoing work which provides the functionality necessary to apply advanced robotics to automated manufacturing and assembly operations. An interface has been built which incorporates 6-DOF tactile manipulation, displays for three dimensional graphical models, and automated tracking functions which depend on automated machine vision. A set of tools for single and multiple focal plane sensor image processing and understanding has been demonstrated which utilizes object recognition models. The resulting tool will enable sensing and planning from computationally simple graphical objects. A synergistic interplay between human and operator vision is created from programmable feedback received from the controller. This approach can be used as the basis for implementing enhanced safety in automated robotics manufacturing, assembly, repair and inspection tasks in both ground and space applications. Thus, an interactive capability has been developed to match the modeled environment to the real task environment for safe and predictable task execution.

The use of interactive computer vision and robot hand controllers for enhancing manufacturing safety

NASA Astrophysics Data System (ADS)

Marzwell, Neville I.; Jacobus, Charles J.; Peurach, Thomas M.; Mitchell, Brian T.

1994-02-01

Current available robotic systems provide limited support for CAD-based model-driven visualization, sensing algorithm development and integration, and automated graphical planning systems. This paper describes ongoing work which provides the functionality necessary to apply advanced robotics to automated manufacturing and assembly operations. An interface has been built which incorporates 6-DOF tactile manipulation, displays for three dimensional graphical models, and automated tracking functions which depend on automated machine vision. A set of tools for single and multiple focal plane sensor image processing and understanding has been demonstrated which utilizes object recognition models. The resulting tool will enable sensing and planning from computationally simple graphical objects. A synergistic interplay between human and operator vision is created from programmable feedback received from the controller. This approach can be used as the basis for implementing enhanced safety in automated robotics manufacturing, assembly, repair and inspection tasks in both ground and space applications. Thus, an interactive capability has been developed to match the modeled environment to the real task environment for safe and predictable task execution.

Radiative Heat Transfer and Turbulence-Radiation Interactions in a Heavy-Duty Diesel Engine

NASA Astrophysics Data System (ADS)

Paul, C.; Sircar, A.; Ferreyro, S.; Imren, A.; Haworth, D. C.; Roy, S.; Ge, W.; Modest, M. F.

2016-11-01

Radiation in piston engines has received relatively little attention to date. Recently, it is being revisited in light of current trends towards higher operating pressures and higher levels of exhaust-gas recirculation, both of which enhance molecular gas radiation. Advanced high-efficiency engines also are expected to function closer to the limits of stable operation, where even small perturbations to the energy balance can have a large influence on system behavior. Here several different spectral radiation property models and radiative transfer equation (RTE) solvers have been implemented in an OpenFOAM-based engine CFD code, and simulations have been performed for a heavy-duty diesel engine. Differences in computed temperature fields, NO and soot levels, and wall heat transfer rates are shown for different combinations of spectral models and RTE solvers. The relative importance of molecular gas radiation versus soot radiation is examined. And the influence of turbulence-radiation interactions is determined by comparing results obtained using local mean values of composition and temperature to compute radiative emission and absorption with those obtained using a particle-based transported probability density function method. DOE, NSF.

Designing Waveform Sets with Good Correlation and Stopband Properties for MIMO Radar via the Gradient-Based Method

PubMed Central

Tang, Liang; Zhu, Yongfeng; Fu, Qiang

2017-01-01

Waveform sets with good correlation and/or stopband properties have received extensive attention and been widely used in multiple-input multiple-output (MIMO) radar. In this paper, we aim at designing unimodular waveform sets with good correlation and stopband properties. To formulate the problem, we construct two criteria to measure the correlation and stopband properties and then establish an unconstrained problem in the frequency domain. After deducing the phase gradient and the step size, an efficient gradient-based algorithm with monotonicity is proposed to minimize the objective function directly. For the design problem without considering the correlation weights, we develop a simplified algorithm, which only requires a few fast Fourier transform (FFT) operations and is more efficient. Because both of the algorithms can be implemented via the FFT operations and the Hadamard product, they are computationally efficient and can be used to design waveform sets with a large waveform number and waveform length. Numerical experiments show that the proposed algorithms can provide better performance than the state-of-the-art algorithms in terms of the computational complexity. PMID:28468308

Animation graphic interface for the space shuttle onboard computer

NASA Technical Reports Server (NTRS)

Wike, Jeffrey; Griffith, Paul

1989-01-01

Graphics interfaces designed to operate on space qualified hardware challenge software designers to display complex information under processing power and physical size constraints. Under contract to Johnson Space Center, MICROEXPERT Systems is currently constructing an intelligent interface for the LASER DOCKING SENSOR (LDS) flight experiment. Part of this interface is a graphic animation display for Rendezvous and Proximity Operations. The displays have been designed in consultation with Shuttle astronauts. The displays show multiple views of a satellite relative to the shuttle, coupled with numeric attitude information. The graphics are generated using position data received by the Shuttle Payload and General Support Computer (PGSC) from the Laser Docking Sensor. Some of the design considerations include crew member preferences in graphic data representation, single versus multiple window displays, mission tailoring of graphic displays, realistic 3D images versus generic icon representations of real objects, the physical relationship of the observers to the graphic display, how numeric or textual information should interface with graphic data, in what frame of reference objects should be portrayed, recognizing conditions of display information-overload, and screen format and placement consistency.

Radiative Heat Transfer modelling in a Heavy-Duty Diesel Engine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paul, Chandan; Sircar, Arpan; Ferreyro-Fernandez, Sebastian

Detailed radiation modelling in piston engines has received relatively little attention to date. Recently, it is being revisited in light of current trends towards higher operating pressures and higher levels of exhaust-gas recirculation, both of which enhance molecular gas radiation. Advanced high-efficiency engines also are expected to function closer to the limits of stable operation, where even small perturbations to the energy balance can have a large influence on system behavior. Here several different spectral radiation property models and radiative transfer equation (RTE) solvers have been implemented in an OpenFOAM-based engine CFD code, and simulations have been performed for amore » heavy-duty diesel engine. Differences in computed temperature fields, NO and soot levels, and wall heat transfer rates are shown for different combinations of spectral models and RTE solvers. The relative importance of molecular gas radiation versus soot radiation is examined. And the influence of turbulence-radiation interactions is determined by comparing results obtained using local mean values of composition and temperature to compute radiative emission and absorption with those obtained using a particle-based transported probability density function method.« less

Designing Waveform Sets with Good Correlation and Stopband Properties for MIMO Radar via the Gradient-Based Method.

PubMed

Tang, Liang; Zhu, Yongfeng; Fu, Qiang

2017-05-01

Waveform sets with good correlation and/or stopband properties have received extensive attention and been widely used in multiple-input multiple-output (MIMO) radar. In this paper, we aim at designing unimodular waveform sets with good correlation and stopband properties. To formulate the problem, we construct two criteria to measure the correlation and stopband properties and then establish an unconstrained problem in the frequency domain. After deducing the phase gradient and the step size, an efficient gradient-based algorithm with monotonicity is proposed to minimize the objective function directly. For the design problem without considering the correlation weights, we develop a simplified algorithm, which only requires a few fast Fourier transform (FFT) operations and is more efficient. Because both of the algorithms can be implemented via the FFT operations and the Hadamard product, they are computationally efficient and can be used to design waveform sets with a large waveform number and waveform length. Numerical experiments show that the proposed algorithms can provide better performance than the state-of-the-art algorithms in terms of the computational complexity.

Software Supports Distributed Operations via the Internet

NASA Technical Reports Server (NTRS)

Norris, Jeffrey; Backers, Paul; Steinke, Robert

2003-01-01

Multi-mission Encrypted Communication System (MECS) is a computer program that enables authorized, geographically dispersed users to gain secure access to a common set of data files via the Internet. MECS is compatible with legacy application programs and a variety of operating systems. The MECS architecture is centered around maintaining consistent replicas of data files cached on remote computers. MECS monitors these files and, whenever one is changed, the changed file is committed to a master database as soon as network connectivity makes it possible to do so. MECS provides subscriptions for remote users to automatically receive new data as they are generated. Remote users can be producers as well as consumers of data. Whereas a prior program that provides some of the same services treats disconnection of a user from the network of users as an error from which recovery must be effected, MECS treats disconnection as a nominal state of the network: This leads to a different design that is more efficient for serving many users, each of whom typically connects and disconnects frequently and wants only a small fraction of the data at any given time.

Operational Use of GPS Navigation for Space Shuttle Entry

NASA Technical Reports Server (NTRS)

Goodman, John L.; Propst, Carolyn A.

2008-01-01

The STS-118 flight of the Space Shuttle Endeavour was the first shuttle mission flown with three Global Positioning System (GPS) receivers in place of the three legacy Tactical Air Navigation (TACAN) units. This marked the conclusion of a 15 year effort involving procurement, missionization, integration, and flight testing of a GPS receiver and a parallel effort to formulate and implement shuttle computer software changes to support GPS. The use of GPS data from a single receiver in parallel with TACAN during entry was successfully demonstrated by the orbiters Discovery and Atlantis during four shuttle missions in 2006 and 2007. This provided the confidence needed before flying the first all GPS, no TACAN flight with Endeavour. A significant number of lessons were learned concerning the integration of a software intensive navigation unit into a legacy avionics system. These lessons have been taken into consideration during vehicle design by other flight programs, including the vehicle that will replace the Space Shuttle, Orion.

Control of coherent information via on-chip photonic–phononic emitter–receivers

DOE PAGES

Shin, Heedeuk; Cox, Jonathan A.; Jarecki, Robert; ...

2015-03-05

We report that rapid progress in integrated photonics has fostered numerous chip-scale sensing, computing and signal processing technologies. However, many crucial filtering and signal delay operations are difficult to perform with all-optical devices. Unlike photons propagating at luminal speeds, GHz-acoustic phonons moving at slower velocities allow information to be stored, filtered and delayed over comparatively smaller length-scales with remarkable fidelity. Hence, controllable and efficient coupling between coherent photons and phonons enables new signal processing technologies that greatly enhance the performance and potential impact of integrated photonics. Here we demonstrate a mechanism for coherent information processing based on travelling-wave photon–phonon transduction,more » which achieves a phonon emit-and-receive process between distinct nanophotonic waveguides. Using this device, physics—which supports GHz frequencies—we create wavelength-insensitive radiofrequency photonic filters with frequency selectivity, narrow-linewidth and high power-handling in silicon. More generally, this emit-receive concept is the impetus for enabling new signal processing schemes.« less

Control of coherent information via on-chip photonic–phononic emitter–receivers

PubMed Central

Shin, Heedeuk; Cox, Jonathan A.; Jarecki, Robert; Starbuck, Andrew; Wang, Zheng; Rakich, Peter T.

2015-01-01

Rapid progress in integrated photonics has fostered numerous chip-scale sensing, computing and signal processing technologies. However, many crucial filtering and signal delay operations are difficult to perform with all-optical devices. Unlike photons propagating at luminal speeds, GHz-acoustic phonons moving at slower velocities allow information to be stored, filtered and delayed over comparatively smaller length-scales with remarkable fidelity. Hence, controllable and efficient coupling between coherent photons and phonons enables new signal processing technologies that greatly enhance the performance and potential impact of integrated photonics. Here we demonstrate a mechanism for coherent information processing based on travelling-wave photon–phonon transduction, which achieves a phonon emit-and-receive process between distinct nanophotonic waveguides. Using this device, physics—which supports GHz frequencies—we create wavelength-insensitive radiofrequency photonic filters with frequency selectivity, narrow-linewidth and high power-handling in silicon. More generally, this emit-receive concept is the impetus for enabling new signal processing schemes. PMID:25740405

School children's use of computers and teachers' education in computer ergonomics.

PubMed

Dockrell, S; Fallon, E; Kelly, M; Masterson, B; Shields, N

2007-10-01

A national survey to investigate the education of teachers in computer-related ergonomics was carried out by postal questionnaire. The use of computers by primary school children (age 4-12 years) was also investigated. Data were collected from a random sample of 25% (n = 830) of primary schools in the Republic of Ireland. Questionnaires (n = 1863) were returned from 416 schools giving a response rate of 50.1%. Almost all schools (99.7%) had computers for children's use. The computers were most often (69.8%) used in the classroom. The majority (56.3%) of children worked in pairs. Most teachers (89.6%) had received computer training, but few (17.6%) had received ergonomics information during the training. Respondents were not satisfied with their current knowledge of ergonomics. Over 90% stated that they would like to receive further information by printed format or during a training course, rather than by computer (web or CD-ROM).

Quantitative Ultrasound for Measuring Obstructive Severity in Children with Hydronephrosis.

PubMed

Cerrolaza, Juan J; Peters, Craig A; Martin, Aaron D; Myers, Emmarie; Safdar, Nabile; Linguraru, Marius George

2016-04-01

We define sonographic biomarkers for hydronephrotic renal units that can predict the necessity of diuretic nuclear renography. We selected a cohort of 50 consecutive patients with hydronephrosis of varying severity in whom 2-dimensional sonography and diuretic mercaptoacetyltriglycine renography had been performed. A total of 131 morphological parameters were computed using quantitative image analysis algorithms. Machine learning techniques were then applied to identify ultrasound based safety thresholds that agreed with the t½ for washout. A best fit model was then derived for each threshold level of t½ that would be clinically relevant at 20, 30 and 40 minutes. Receiver operating characteristic curve analysis was performed. Sensitivity, specificity and area under the receiver operating characteristic curve were determined. Improvement obtained by the quantitative imaging method compared to the Society for Fetal Urology grading system and the hydronephrosis index was statistically verified. For the 3 thresholds considered and at 100% sensitivity the specificities of the quantitative imaging method were 94%, 70% and 74%, respectively. Corresponding area under the receiver operating characteristic curve values were 0.98, 0.94 and 0.94, respectively. Improvement obtained by the quantitative imaging method over the Society for Fetal Urology grade and hydronephrosis index was statistically significant (p <0.05 in all cases). Quantitative imaging analysis of renal sonograms in children with hydronephrosis can identify thresholds of clinically significant washout times with 100% sensitivity to decrease the number of diuretic renograms in up to 62% of children. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Does intraoperative navigation improve the accuracy of mandibular angle osteotomy: Comparison between augmented reality navigation, individualised templates and free-hand techniques.

PubMed

Zhu, Ming; Liu, Fei; Zhou, Chaozheng; Lin, Li; Zhang, Yan; Chai, Gang; Xie, Le; Qi, Fazhi; Li, Qingfeng

2018-04-11

Augmented reality (AR)-based navigation surgery has evolved to be an advanced assisted technology. The aim of this study is to manifest the accuracy of AR navigation for the intraoperative mandibular angle osteotomy by comparing the navigation with other interventional techniques. A retrospective study was conducted with 93 post-surgical patients with mandibular angle hypertrophy admitted at our plastic and reconstructive surgery department between September 2011 and June 2016. Thirty-one patients received osteotomy conducted using a navigation system based on augmented reality (AR group), 28 patients received osteotomy conducted using individualised templates (IT group) and the remaining 34 patients received osteotomy performed by free hand (free-hand group). The post-operative computed tomography (CT) images were reviewed and analysed by comparing with pre-surgical planning generated by three-dimensional (3D) software. The preparation time, cutting time, whole operating time and discrepancy in osteotomy lines were measured. The preparation time was much shorter for the free-hand group than that for the AR group and the IT group (P < 0.01). However, no significant difference in the whole operating time was observed among the three groups (P > 0.05). In addition, the discrepancy in osteotomy lines was lower for the AR group and in the IT group than for the free-hand group (P < 0.01). The navigation system based on AR has a higher accuracy, more reliability and better user friendliness for some particular clinical procedures than for other techniques, which has a promising clinical prospect. Copyright © 2018. Published by Elsevier Ltd.

Using convolutional decoding to improve time delay and phase estimation in digital communications

DOEpatents

Ormesher, Richard C [Albuquerque, NM; Mason, John J [Albuquerque, NM

2010-01-26

The time delay and/or phase of a communication signal received by a digital communication receiver can be estimated based on a convolutional decoding operation that the communication receiver performs on the received communication signal. If the original transmitted communication signal has been spread according to a spreading operation, a corresponding despreading operation can be integrated into the convolutional decoding operation.

HEAP: Heat Energy Analysis Program, a computer model simulating solar receivers. [solving the heat transfer problem

NASA Technical Reports Server (NTRS)

Lansing, F. L.

1979-01-01

A computer program which can distinguish between different receiver designs, and predict transient performance under variable solar flux, or ambient temperatures, etc. has a basic structure that fits a general heat transfer problem, but with specific features that are custom-made for solar receivers. The code is written in MBASIC computer language. The methodology followed in solving the heat transfer problem is explained. A program flow chart, an explanation of input and output tables, and an example of the simulation of a cavity-type solar receiver are included.

Performing an allreduce operation on a plurality of compute nodes of a parallel computer

DOEpatents

Faraj, Ahmad [Rochester, MN

2012-04-17

Methods, apparatus, and products are disclosed for performing an allreduce operation on a plurality of compute nodes of a parallel computer. Each compute node includes at least two processing cores. Each processing core has contribution data for the allreduce operation. Performing an allreduce operation on a plurality of compute nodes of a parallel computer includes: establishing one or more logical rings among the compute nodes, each logical ring including at least one processing core from each compute node; performing, for each logical ring, a global allreduce operation using the contribution data for the processing cores included in that logical ring, yielding a global allreduce result for each processing core included in that logical ring; and performing, for each compute node, a local allreduce operation using the global allreduce results for each processing core on that compute node.

[On-line data management system using a portable blood gas analyzer in the operating room].

PubMed

Shimosato, G; Ibuki, T; Hirata, M; Shigemi, K; Tanaka, Y

2000-03-01

It is very important to establish a clinical testing system which is not only prompt, simple and accurate but also safe for the patients and medical staff in the operating room, emergency room and intensive care unit. In our institution an i-STAT portable blood gas analyser has been widely used for point of care testing in all the operating rooms. This clinical testing system has been upgraded by adding an i-STAT communication protocol to our online data management system. The analysed data transmitted by the i-STAT as an infrared signal is transformed to an electronic signal through the IR link and sent to the central data station (CDS) via RS232C. The data received by the CDS is then sent to the upper grade computer system where the data is recorded on the hard disk. One advantage of this system is that it is connected to the hospital computer system. Not only does this new system meet the need for accurate, safe, effective and economical laboratory testing, but also retrospective and multifactorial analysis of intraoperative events can be easily carried out. In the future this system can be applied to telemedicine through the Internet and contribute to the treatment of critically ill patients.

Sway control method and system for rotary cranes

DOEpatents

Robinett, R.D.; Parker, G.G.; Feddema, J.T.; Dohrmann, C.R.; Petterson, B.J.

1999-06-01

Methods and apparatuses are disclosed for reducing the oscillatory motion of rotary crane payloads during operator-commanded or computer-controlled maneuvers. An Input-shaping filter receives input signals from multiple operator input devices and converts them into output signals readable by the crane controller to dampen the payload tangential and radial sway associated with rotation of the jib. The input signals are characterized by a hub rotation trajectory [gamma](t), which includes a jib angular acceleration [gamma], a trolley acceleration x, and a load-line length velocity L. The system state variables are characterized by a tangential rotation angle [theta](t) and a radial rotation angle [phi](t) of the load-line. The coupled equations of motion governing the filter are non-linear and configuration-dependent. In one embodiment, a filter is provided between the operator and the crane for filtering undesired frequencies from the angular [gamma] and trolley x velocities to suppress payload oscillation. In another embodiment, crane commands are computer generated and controlled to suppress vibration of the payload using a postulated asymmetrical shape for the acceleration profiles of the jib, which profiles are uniquely determined by a set of parameters (including the acceleration pulse amplitude and the duration and coast time between pulses), or a dynamic programming approach. 25 figs.

Sway control method and system for rotary cranes

DOEpatents

Robinett, Rush D.; Parker, Gordon G.; Feddema, John T.; Dohrmann, Clark R.; Petterson, Ben J.

1999-01-01

Methods and apparatuses for reducing the oscillatory motion of rotary crane payloads during operator-commanded or computer-controlled maneuvers. An Input-shaping filter receives input signals from multiple operator input devices and converts them into output signals readable by the crane controller to dampen the payload tangential and radial sway associated with rotation of the jib. The input signals are characterized by a hub rotation trajectory .gamma.(t), which includes a jib angular acceleration .gamma., a trolley acceleration x, and a load-line length velocity L. The system state variables are characterized by a tangential rotation angle .theta.(t) and a radial rotation angle .phi.(t) of the load-line. The coupled equations of motion governing the filter are non-linear and configuration-dependent. In one embodiment, a filter is provided between the operator and the crane for filtering undesired frequencies from the angular .gamma. and trolley x velocities to suppress payload oscillation. In another embodiment, crane commands are computer generated and controlled to suppress vibration of the payload using a postulated asymmetrical shape for the acceleration profiles of the jib, which profiles are uniquely determined by a set of parameters (including the acceleration pulse amplitude and the duration and coast time between pulses), or a dynamic programming approach.

Computer Simulated Visual and Tactile Feedback as an Aid to Manipulator and Vehicle Control,

DTIC Science & Technology

1981-05-08

STATEMENT ........................ 8 Artificial Intellegence Versus Supervisory Control ....... 8 Computer Generation of Operator Feedback...operator. Artificial Intelligence Versus Supervisory Control The use of computers to aid human operators can be divided into two catagories: artificial ...operator. Artificial intelligence ( A. I. ) attempts to give the computer maximum intelligence and to replace all operator functions by the computer

Development of Radar Control system for Multi-mode Active Phased Array Radar for atmospheric probing

NASA Astrophysics Data System (ADS)

Yasodha, Polisetti; Jayaraman, Achuthan; Thriveni, A.

2016-07-01

Modern multi-mode active phased array radars require highly efficient radar control system for hassle free real time radar operation. The requirement comes due to the distributed architecture of the active phased array radar, where each antenna element in the array is connected to a dedicated Transmit-Receive (TR) module. Controlling the TR modules, which are generally few hundreds in number, and functioning them in synchronisation, is a huge task during real time radar operation and should be handled with utmost care. Indian MST Radar, located at NARL, Gadanki, which is established during early 90's, as an outcome of the middle atmospheric program, is a remote sensing instrument for probing the atmosphere. This radar has a semi-active array, consisting of 1024 antenna elements, with limited beam steering, possible only along the principle planes. To overcome the limitations and difficulties, the radar is being augmented into fully active phased array, to accomplish beam agility and multi-mode operations. Each antenna element is excited with a dedicated 1 kW TR module, located in the field and enables to position the radar beam within 20° conical volume. A multi-channel receiver makes the radar to operate in various modes like Doppler Beam Swinging (DBS), Spaced Antenna (SA), Frequency Domain Interferometry (FDI) etc. Present work describes the real-time radar control (RC) system for the above described active phased array radar. The radar control system consists of a Spartan 6 FPGA based Timing and Control Signal Generator (TCSG), and a computer containing the software for controlling all the subsystems of the radar during real-time radar operation and also for calibrating the radar. The main function of the TCSG is to generate the control and timing waveforms required for various subsystems of the radar. Important components of the RC system software are (i) TR module configuring software which does programming, controlling and health parameter monitoring of the TR modules, (ii) radar operation software which facilitates experimental parameter setting and operating the radar in different modes, (iii) beam steering software which computes the amplitude co-efficients and phases required for each TR module, for forming the beams selected for radar operation with the desired shape and (iv) Calibration software for calibrating the radar by measuring the differential insertion phase and amplitudes in all 1024 Transmit and Receive paths and correcting them. The TR module configuring software is a major task as it needs to control 1024 TR modules, which are located in the field about 150 m away from the RC system in the control room. Each TR module has a processor identified with a dedicated IP address, along with memory to store the instructions and parameters required for radar operation. A communication link is designed using Gigabit Ethernet (GbE) switches to realise 1 to 1024 way switching network. RC system computer communicates with the each processor using its IP address and establishes connection, via 1 to 1024 port GbE switching network. The experimental parameters data are pre-loaded parallely into all the TR modules along with the phase shifter data required for beam steering using this network. A reference timing pulse is sent to all the TR modules simultaneously, which indicates the start of radar operation. RC system also monitors the status parameters from the TR modules indicating their health during radar operation at regular intervals, via GbE switching network. Beam steering software generates the phase shift required for each TR module for the beams selected for operation. Radar operational software calls the phase shift data required for beam steering and adds it to the calibration phase obtained through calibration software and loads the resultant phase data into TR modules. Timed command/data transfer to/from subsystems and synchronisation of subsystems is essential for proper real-time operation of the active phased array radar and the RC system ensures that the commands/experimental parameter data are properly transferred to all subsystems especially to TR modules. In case of failure of any TR module, it is indicated to the user for further rectification. Realisation of the RC system is at an advanced stage. More details will be presented in the conference.

Exploring the use of I/O nodes for computation in a MIMD multiprocessor

NASA Technical Reports Server (NTRS)

Kotz, David; Cai, Ting

1995-01-01

As parallel systems move into the production scientific-computing world, the emphasis will be on cost-effective solutions that provide high throughput for a mix of applications. Cost effective solutions demand that a system make effective use of all of its resources. Many MIMD multiprocessors today, however, distinguish between 'compute' and 'I/O' nodes, the latter having attached disks and being dedicated to running the file-system server. This static division of responsibilities simplifies system management but does not necessarily lead to the best performance in workloads that need a different balance of computation and I/O. Of course, computational processes sharing a node with a file-system service may receive less CPU time, network bandwidth, and memory bandwidth than they would on a computation-only node. In this paper we begin to examine this issue experimentally. We found that high performance I/O does not necessarily require substantial CPU time, leaving plenty of time for application computation. There were some complex file-system requests, however, which left little CPU time available to the application. (The impact on network and memory bandwidth still needs to be determined.) For applications (or users) that cannot tolerate an occasional interruption, we recommend that they continue to use only compute nodes. For tolerant applications needing more cycles than those provided by the compute nodes, we recommend that they take full advantage of both compute and I/O nodes for computation, and that operating systems should make this possible.

Emergent Literacy Development and Computer Assisted Instruction

ERIC Educational Resources Information Center

Trotti, Judy; Hendricks, Randy; Bledsoe, Christie

2017-01-01

In this mixed-methods study, researchers examined the literacy development of prekindergarten students (N = 162) randomly placed in one of two treatment groups with each receiving 15 minutes of computer-assisted literacy instruction for four months. Literacy development of a control group of children not receiving computer-assisted instruction was…

Increased Pericardial Fat Volume Measured From Noncontrast CT Predicts Myocardial Ischemia by SPECT

PubMed Central

Tamarappoo, Balaji; Dey, Damini; Shmilovich, Haim; Nakazato, Ryo; Gransar, Heidi; Cheng, Victor Y.; Friedman, John D.; Hayes, Sean W.; Thomson, Louise EJ; Slomka, Piotr J.; Rozanski, Alan; Berman, Daniel S.

2010-01-01

OBJECTIVES We evaluated the association between pericardial fat and myocardial ischemia for risk stratification. BACK GROUND Pericardial fat volume (PFV) and thoracic fat volume (TFV) measured from noncontrast computed tomography (CT) performed for calculating coronary calcium score (CCS) are associated with increased CCS and risk for major adverse cardiovascular events. METHODS From a cohort of 1,777 consecutive patients without previously known coronary artery disease (CAD) with noncontrast CT performed within 6 months of single photon emission computed tomography (SPECT), we compared 73 patients with ischemia by SPECT (cases) with 146 patients with normal SPECT (controls) matched by age, gender, CCS category, and symptoms and risk factors for CAD. TFV was automatically measured. Pericardial contours were manually defined within which fat voxels were automatically identified to compute PFV. Computer-assisted visual interpretation of SPECT was performed using standard 17-segment and 5-point score model; perfusion defect was quantified as summed stress score (SSS) and summed rest score (SRS). Ischemia was defined by: SSS – SRS ≥4. Independent relationships of PFV and TFV to ischemia were examined. RESULTS Cases had higher mean PFV (99.1 ± 42.9 cm3 vs. 80.1 ± 31.8 cm3, p = 0.0003) and TFV (196.1 ± 82.7 cm3 vs. 160.8 ± 72.1 cm3, p = 0.001) and higher frequencies of PFV >125 cm3 (22% vs. 8%, p = 0.004) and TFV >200 cm3 (40% vs. 19%, p = 0.001) than controls. After adjustment for CCS, PFV and TFV remained the strongest predictors of ischemia (odds ratio [OR]: 2.91, 95% confidence interval [CI]: 1.53 to 5.52, p = 0.001 for each doubling of PFV; OR: 2.64, 95% CI: 1.48 to 4.72, p = 0.001 for TFV. Receiver operating characteristic analysis showed that prediction of ischemia, as indicated by receiver-operator characteristic area under the curve, improved significantly when PFV or TFV was added to CCS (0.75 vs. 0.68, p = 0.04 for both). CONCLUSIONS Pericardial fat was significantly associated with myocardial ischemia in patients without known CAD and may help improve risk assessment. PMID:21070997

Discrimination between patients with mild Alzheimer's disease and healthy subjects based on cerebral blood flow images of the lateral views in xenon-enhanced computed tomography.

PubMed

Sase, Shigeru; Yamamoto, Homaro; Kawashima, Ena; Tan, Xin; Sawa, Yutaka

2018-01-01

Quantitative cerebral blood flow (CBF) measurement is expected to help early detection of functional abnormalities caused by Alzheimer's disease (AD) and enable AD treatment to begin in its early stages. Recently, a technique of layer analysis was reported that allowed CBF to be analyzed from the outer to inner layers of the brain. The aim of this work was to develop methods for discriminating between patients with mild AD and healthy subjects based on CBF images of the lateral views created with the layer analysis technique in xenon-enhanced computed tomography. Xenon-enhanced computed tomography using a wide-volume CT was performed on 17 patients with mild AD aged 75 or older and on 15 healthy age-matched volunteers. For each subject, we created CBF images of the right and left lateral views with a depth of 10-15 mm from the surface of the brain. Ten circular regions of interest (ROI) were placed on each image, and CBF was calculated for each ROI. We determined discriminant ROI that had CBF that could be used to differentiate between the AD and volunteer groups. AD patients' CBF range (mean - SD to mean + SD) and healthy volunteers' CBF range (mean - SD to mean + SD) were obtained for each ROI. Receiver-operator curves were created to identify patients with AD for each of the discriminant ROI and for the AD patients' and healthy volunteers' CBF ranges. We selected an ROI on both the right and left temporal lobes as the discriminant ROI. Areas under the receiver-operator curve were 93.3% using the ROI on the right temporal lobe, 95.3% using the ROI on the left temporal lobe, and 92.4% using the AD patients' and healthy volunteers' CBF ranges. We could effectively discriminate between patients with mild AD and healthy subjects using ROI placed on CBF images of the lateral views in xenon-enhanced computed tomography. © 2017 Japanese Psychogeriatric Society.

The equipment access software for a distributed UNIX-based accelerator control system

NASA Astrophysics Data System (ADS)

Trofimov, Nikolai; Zelepoukine, Serguei; Zharkov, Eugeny; Charrue, Pierre; Gareyte, Claire; Poirier, Hervé

1994-12-01

This paper presents a generic equipment access software package for a distributed control system using computers with UNIX or UNIX-like operating systems. The package consists of three main components, an application Equipment Access Library, Message Handler and Equipment Data Base. An application task, which may run in any computer in the network, sends requests to access equipment through Equipment Library calls. The basic request is in the form Equipment-Action-Data and is routed via a remote procedure call to the computer to which the given equipment is connected. In this computer the request is received by the Message Handler. According to the type of the equipment connection, the Message Handler either passes the request to the specific process software in the same computer or forwards it to a lower level network of equipment controllers using MIL1553B, GPIB, RS232 or BITBUS communication. The answer is then returned to the calling application. Descriptive information required for request routing and processing is stored in the real-time Equipment Data Base. The package has been written to be portable and is currently available on DEC Ultrix, LynxOS, HPUX, XENIX, OS-9 and Apollo domain.

Modeling resident error-making patterns in detection of mammographic masses using computer-extracted image features: preliminary experiments

NASA Astrophysics Data System (ADS)

Mazurowski, Maciej A.; Zhang, Jing; Lo, Joseph Y.; Kuzmiak, Cherie M.; Ghate, Sujata V.; Yoon, Sora

2014-03-01

Providing high quality mammography education to radiology trainees is essential, as good interpretation skills potentially ensure the highest benefit of screening mammography for patients. We have previously proposed a computer-aided education system that utilizes trainee models, which relate human-assessed image characteristics to interpretation error. We proposed that these models be used to identify the most difficult and therefore the most educationally useful cases for each trainee. In this study, as a next step in our research, we propose to build trainee models that utilize features that are automatically extracted from images using computer vision algorithms. To predict error, we used a logistic regression which accepts imaging features as input and returns error as output. Reader data from 3 experts and 3 trainees were used. Receiver operating characteristic analysis was applied to evaluate the proposed trainee models. Our experiments showed that, for three trainees, our models were able to predict error better than chance. This is an important step in the development of adaptive computer-aided education systems since computer-extracted features will allow for faster and more extensive search of imaging databases in order to identify the most educationally beneficial cases.

Providing nearest neighbor point-to-point communications among compute nodes of an operational group in a global combining network of a parallel computer

DOEpatents

Archer, Charles J.; Faraj, Ahmad A.; Inglett, Todd A.; Ratterman, Joseph D.

2012-10-23

Methods, apparatus, and products are disclosed for providing nearest neighbor point-to-point communications among compute nodes of an operational group in a global combining network of a parallel computer, each compute node connected to each adjacent compute node in the global combining network through a link, that include: identifying each link in the global combining network for each compute node of the operational group; designating one of a plurality of point-to-point class routing identifiers for each link such that no compute node in the operational group is connected to two adjacent compute nodes in the operational group with links designated for the same class routing identifiers; and configuring each compute node of the operational group for point-to-point communications with each adjacent compute node in the global combining network through the link between that compute node and that adjacent compute node using that link's designated class routing identifier.

Influence of Computer-Aided Detection on Performance of Screening Mammography

PubMed Central

Fenton, Joshua J.; Taplin, Stephen H.; Carney, Patricia A.; Abraham, Linn; Sickles, Edward A.; D'Orsi, Carl; Berns, Eric A.; Cutter, Gary; Hendrick, R. Edward; Barlow, William E.; Elmore, Joann G.

2011-01-01

Background Computer-aided detection identifies suspicious findings on mammograms to assist radiologists. Since the Food and Drug Administration approved the technology in 1998, it has been disseminated into practice, but its effect on the accuracy of interpretation is unclear. Methods We determined the association between the use of computer-aided detection at mammography facilities and the performance of screening mammography from 1998 through 2002 at 43 facilities in three states. We had complete data for 222,135 women (a total of 429,345 mammograms), including 2351 women who received a diagnosis of breast cancer within 1 year after screening. We calculated the specificity, sensitivity, and positive predictive value of screening mammography with and without computer-aided detection, as well as the rates of biopsy and breast-cancer detection and the overall accuracy, measured as the area under the receiver-operating-characteristic (ROC) curve. Results Seven facilities (16%) implemented computer-aided detection during the study period. Diagnostic specificity decreased from 90.2% before implementation to 87.2% after implementation (P<0.001), the positive predictive value decreased from 4.1% to 3.2% (P = 0.01), and the rate of biopsy increased by 19.7% (P<0.001). The increase in sensitivity from 80.4% before implementation of computer-aided detection to 84.0% after implementation was not significant (P = 0.32). The change in the cancer-detection rate (including invasive breast cancers and ductal carcinomas in situ) was not significant (4.15 cases per 1000 screening mammograms before implementation and 4.20 cases after implementation, P = 0.90). Analyses of data from all 43 facilities showed that the use of computer-aided detection was associated with significantly lower overall accuracy than was nonuse (area under the ROC curve, 0.871 vs. 0.919; P = 0.005). Conclusions The use of computer-aided detection is associated with reduced accuracy of interpretation of screening mammograms. The increased rate of biopsy with the use of computer-aided detection is not clearly associated with improved detection of invasive breast cancer. PMID:17409321

Theoretical assessment of the maximum obtainable power in wireless power transfer constrained by human body exposure limits in a typical room scenario.

PubMed

Chen, Xi Lin; De Santis, Valerio; Umenei, Aghuinyue Esai

2014-07-07

In this study, the maximum received power obtainable through wireless power transfer (WPT) by a small receiver (Rx) coil from a relatively large transmitter (Tx) coil is numerically estimated in the frequency range from 100 kHz to 10 MHz based on human body exposure limits. Analytical calculations were first conducted to determine the worst-case coupling between a homogeneous cylindrical phantom with a radius of 0.65 m and a Tx coil positioned 0.1 m away with the radius ranging from 0.25 to 2.5 m. Subsequently, three high-resolution anatomical models were employed to compute the peak induced field intensities with respect to various Tx coil locations and dimensions. Based on the computational results, scaling factors which correlate the cylindrical phantom and anatomical model results were derived. Next, the optimal operating frequency, at which the highest transmitter source power can be utilized without exceeding the exposure limits, is found to be around 2 MHz. Finally, a formulation is proposed to estimate the maximum obtainable power of WPT in a typical room scenario while adhering to the human body exposure compliance mandates.

Theoretical assessment of the maximum obtainable power in wireless power transfer constrained by human body exposure limits in a typical room scenario

NASA Astrophysics Data System (ADS)

Chen, Xi Lin; De Santis, Valerio; Esai Umenei, Aghuinyue

2014-07-01

In this study, the maximum received power obtainable through wireless power transfer (WPT) by a small receiver (Rx) coil from a relatively large transmitter (Tx) coil is numerically estimated in the frequency range from 100 kHz to 10 MHz based on human body exposure limits. Analytical calculations were first conducted to determine the worst-case coupling between a homogeneous cylindrical phantom with a radius of 0.65 m and a Tx coil positioned 0.1 m away with the radius ranging from 0.25 to 2.5 m. Subsequently, three high-resolution anatomical models were employed to compute the peak induced field intensities with respect to various Tx coil locations and dimensions. Based on the computational results, scaling factors which correlate the cylindrical phantom and anatomical model results were derived. Next, the optimal operating frequency, at which the highest transmitter source power can be utilized without exceeding the exposure limits, is found to be around 2 MHz. Finally, a formulation is proposed to estimate the maximum obtainable power of WPT in a typical room scenario while adhering to the human body exposure compliance mandates.

Design and evaluation of a high temperature/pressure supercritical carbon dioxide direct tubular receiver for concentrating solar power applications

NASA Astrophysics Data System (ADS)

Ortega, Jesus Daniel

This work focuses on the development of a solar power thermal receiver for a supercritical-carbon dioxide (sCO2), Brayton power-cycle to produce ~1 MWe. Closed-loop sCO2 Brayton cycles are being evaluated in combination with concentrating solar power to provide higher thermal-to-electric conversion efficiencies relative to conventional steam Rankine cycles. High temperatures (923--973 K) and pressures (20--25 MPa) are required in the solar receiver to achieve thermal efficiencies of ~50%, making concentrating solar power (CSP) technologies a competitive alternative to current power generation methods. In this study, the CSP receiver is required to achieve an outlet temperature of 923 K at 25 MPa or 973 K at 20 MPa to meet the operating needs. To obtain compatible receiver tube material, an extensive material review was performed based the ASME Boiler and Pressure Vessel Code, ASME B31.1 and ASME B313.3 codes respectively. Subsequently, a thermal-structural model was developed using a commercial computational fluid (CFD) dynamics and structural mechanics software for designing and analyzing the tubular receiver that could provide the heat input for a ~2 MWth plant. These results were used to perform an analytical cumulative damage creep-fatigue analysis to estimate the work-life of the tubes. In sequence, an optical-thermal-fluid model was developed to evaluate the resulting thermal efficiency of the tubular receiver from the NSTTF heliostat field. The ray-tracing tool SolTrace was used to obtain the heat-flux distribution on the surfaces of the receiver. The K-ω SST turbulence model and P-1 radiation model used in Fluent were coupled with SolTrace to provide the heat flux distribution on the receiver surface. The creep-fatigue analysis displays the damage accumulated due to the cycling and the permanent deformation of the tubes. Nonetheless, they are able to support the required lifetime. The receiver surface temperatures were found to be within the safe operational limit while exhibiting a receiver thermal efficiency of ~85%. Future work includes the completion of a cyclic loading analysis to be performed using the Larson-Miller creep model in nCode Design Life to corroborate the structural integrity of the receiver over the desired lifetime of ~10,000 cycles.

The relationship of storm severity to directionally resolved radio emissions

NASA Technical Reports Server (NTRS)

Johnson, R. O.; Bushman, M. L.; Sherrill, W. M.

1980-01-01

Directionally resolved atmospheric radio frequency emission data were acquired from thunderstorms occurring in the central and southwestern United States. In addition, RF sferic tracking data were obtained from hurricanes and tropical depressions occurring in the Gulf of Mexico. The data were acquired using a crossed baseline phase interferometer operating at a frequency of 2.001 MHz. The received atmospherics were tested for phase linearity across the array, and azimuth/elevation angles of arrival were computed in real time. A histogram analysis of sferic burst count versus azimuth provided lines of bearing to centers of intense electrical activity. Analysis indicates a consistent capability of the phase linear direction finder to detect severe meteorological activity to distances of 2000 km from the receiving site. The technique evidences the ability to discriminate severe storms from nonsevere storms coexistent in large regional scale thunderstorm activity.

Missed deadline notification in best-effort schedulers

NASA Astrophysics Data System (ADS)

Banachowski, Scott A.; Wu, Joel; Brandt, Scott A.

2003-12-01

It is common to run multimedia and other periodic, soft real-time applications on general-purpose computer systems. These systems use best-effort scheduling algorithms that cannot guarantee applications will receive responsive scheduling to meet deadline or timing requirements. We present a simple mechanism called Missed Deadline Notification (MDN) that allows applications to notify the system when they do not receive their desired level of responsiveness. Consisting of a single system call with no arguments, this simple interface allows the operating system to provide better support for soft real-time applications without any a priori information about their timing or resource needs. We implemented MDN in three different schedulers: Linux, BEST, and BeRate. We describe these implementations and their performance when running real-time applications and discuss policies to prevent applications from abusing MDN to gain extra resources.

Distributed downhole drilling network

DOEpatents

Hall, David R.; Hall, Jr., H. Tracy; Fox, Joe; Pixton, David S.

2006-11-21

A high-speed downhole network providing real-time data from downhole components of a drilling strings includes a bottom-hole node interfacing to a bottom-hole assembly located proximate the bottom end of a drill string. A top-hole node is connected proximate the top end of the drill string. One or several intermediate nodes are located along the drill string between the bottom-hole node and the top-hole node. The intermediate nodes are configured to receive and transmit data packets transmitted between the bottom-hole node and the top-hole node. A communications link, integrated into the drill string, is used to operably connect the bottom-hole node, the intermediate nodes, and the top-hole node. In selected embodiments, a personal or other computer may be connected to the top-hole node, to analyze data received from the intermediate and bottom-hole nodes.

Optical attenuation mechanism upgrades, MOBLAS, and TLRS systems

NASA Technical Reports Server (NTRS)

Eichinger, Richard; Johnson, Toni; Malitson, Paul; Oldham, Thomas; Stewart, Loyal

1993-01-01

This poster presentation describes the Optical Attenuation Mechanism (OAM) Upgrades to the MOBLAS and TLRS Crustal Dynamics Satellite Laser Ranging (CDSLR) systems. The upgrades were for the purposes of preparing these systems to laser range to the TOPEX/POSEIDON spacecraft when it will be launched in the summer of 1992. The OAM permits the laser receiver to operate over the expected large signal dynamic range from TOPEX/POSEIDON and it reduces the number of pre- and post-calibrations for each satellite during multi-satellite tracking operations. It further simplifies the calibration bias corrections that had been made due to the pass-to-pass variation of the photomultiplier supply voltage and the transmit filter glass thickness. The upgrade incorporated improvements to the optical alignment capability of each CDSLR system through the addition of a CCD camera into the MOBLAS receive telescope and an alignment telescope onto the TLRS optical table. The OAM is stepper motor and microprocessor based; and the system can be controlled either manually by a control switch panel or computer controlled via an EIA RS-232C serial interface. The OAM has a neutral density (ND) range of 0.0 to 4.0 and the positioning is absolute referenced in steps of 0.1 ND. Both the fixed transmit filter and the daylight filter are solenoid actuated with digital inputs and outputs to and from the OAM microprocessor. During automated operation, the operator has the option to overide the remote control and control the OAM system via a local control switch panel.

Comparison of computed radiography and conventional radiography in detection of small volume pneumoperitoneum.

PubMed

Marolf, Angela; Blaik, Margaret; Ackerman, Norman; Watson, Elizabeth; Gibson, Nicole; Thompson, Margret

2008-01-01

The role of digital imaging is increasing as these systems are becoming more affordable and accessible. Advantages of computed radiography compared with conventional film/screen combinations include improved contrast resolution and postprocessing capabilities. Computed radiography's spatial resolution is inferior to conventional radiography; however, this limitation is considered clinically insignificant. This study prospectively compared digital imaging and conventional radiography in detecting small volume pneumoperitoneum. Twenty cadaver dogs (15-30 kg) were injected with 0.25, 0.25, and 0.5 ml for 1 ml total of air intra-abdominally, and radiographed sequentially using computed and conventional radiographic technologies. Three radiologists independently evaluated the images, and receiver operating curve (ROC) analysis compared the two imaging modalities. There was no statistical difference between computed and conventional radiography in detecting free abdominal air, but overall computed radiography was relatively more sensitive based on ROC analysis. Computed radiographic images consistently and significantly demonstrated a minimal amount of 0.5 ml of free air based on ROC analysis. However, no minimal air amount was consistently or significantly detected with conventional film. Readers were more likely to detect free air on lateral computed images than the other projections, with no significant increased sensitivity between film/screen projections. Further studies are indicated to determine the differences or lack thereof between various digital imaging systems and conventional film/screen systems.

Comparison of Three Non-Imaging Angle-Diversity Receivers as Input Sensors of Nodes for Indoor Infrared Wireless Sensor Networks: Theory and Simulation

PubMed Central

Mendoza, Beatriz R.; Rodríguez, Silvestre; Pérez-Jiménez, Rafael; Ayala, Alejandro; González, Oswaldo

2016-01-01

In general, the use of angle-diversity receivers makes it possible to reduce the impact of ambient light noise, path loss and multipath distortion, in part by exploiting the fact that they often receive the desired signal from different directions. Angle-diversity detection can be performed using a composite receiver with multiple detector elements looking in different directions. These are called non-imaging angle-diversity receivers. In this paper, a comparison of three non-imaging angle-diversity receivers as input sensors of nodes for an indoor infrared (IR) wireless sensor network is presented. The receivers considered are the conventional angle-diversity receiver (CDR), the sectored angle-diversity receiver (SDR), and the self-orienting receiver (SOR), which have been proposed or studied by research groups in Spain. To this end, the effective signal-collection area of the three receivers is modelled and a Monte-Carlo-based ray-tracing algorithm is implemented which allows us to investigate the effect on the signal to noise ratio and main IR channel parameters, such as path loss and rms delay spread, of using the three receivers in conjunction with different combination techniques in IR links operating at low bit rates. Based on the results of the simulations, we show that the use of a conventional angle-diversity receiver in conjunction with the equal-gain combining technique provides the solution with the best signal to noise ratio, the lowest computational capacity and the lowest transmitted power requirements, which comprise the main limitations for sensor nodes in an indoor infrared wireless sensor network. PMID:27428966

Computing an operating parameter of a unified power flow controller

DOEpatents

Wilson, David G.; Robinett, III, Rush D.

2017-12-26

A Unified Power Flow Controller described herein comprises a sensor that outputs at least one sensed condition, a processor that receives the at least one sensed condition, a memory that comprises control logic that is executable by the processor; and power electronics that comprise power storage, wherein the processor causes the power electronics to selectively cause the power storage to act as one of a power generator or a load based at least in part upon the at least one sensed condition output by the sensor and the control logic, and wherein at least one operating parameter of the power electronics is designed to facilitate maximal transmittal of electrical power generated at a variable power generation system to a grid system while meeting power constraints set forth by the electrical power grid.

Collective communications apparatus and method for parallel systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Knies, Allan D.; Keppel, David Pardo; Woo, Dong Hyuk

A collective communication apparatus and method for parallel computing systems. For example, one embodiment of an apparatus comprises a plurality of processor elements (PEs); collective interconnect logic to dynamically form a virtual collective interconnect (VCI) between the PEs at runtime without global communication among all of the PEs, the VCI defining a logical topology between the PEs in which each PE is directly communicatively coupled to a only a subset of the remaining PEs; and execution logic to execute collective operations across the PEs, wherein one or more of the PEs receive first results from a first portion of themore » subset of the remaining PEs, perform a portion of the collective operations, and provide second results to a second portion of the subset of the remaining PEs.« less

Computing an operating parameter of a unified power flow controller

DOEpatents

Wilson, David G; Robinett, III, Rush D

2015-01-06

A Unified Power Flow Controller described herein comprises a sensor that outputs at least one sensed condition, a processor that receives the at least one sensed condition, a memory that comprises control logic that is executable by the processor; and power electronics that comprise power storage, wherein the processor causes the power electronics to selectively cause the power storage to act as one of a power generator or a load based at least in part upon the at least one sensed condition output by the sensor and the control logic, and wherein at least one operating parameter of the power electronics is designed to facilitate maximal transmittal of electrical power generated at a variable power generation system to a grid system while meeting power constraints set forth by the electrical power grid.

Administrative Services Staff with New Teleticketing Machine

NASA Image and Video Library

1968-02-21

Peggy Heintz, left, receives an airline ticket from supervisor Judy Kuebeler in the Administrative Services Building at the National Aeronautics and Space Administration (NASA) Lewis Research Center. The center had recently purchased a teleticket machine that automatically printed airline tickets as directed by the airline’s computer system. The Administrative Services Branch had 55 staff members performing a variety of roles. They served as telephone operators and set up communications with other centers. They operated the motor pool, handled all travel arrangements, prepared forms and work instructions, and planned offices. The staff was also responsible for records management and storage. It was reported that the staff processed 65 bags of incoming mail per day, which was said to be on par with a city of 15,000 to 20,000 people.

X-wing fly-by-wire vehicle management system

NASA Technical Reports Server (NTRS)

Fischer, Jr., William C. (Inventor)

1990-01-01

A complete, computer based, vehicle management system (VMS) for X-Wing aircraft using digital fly-by-wire technology controlling many subsystems and providing functions beyond the classical aircraft flight control system. The vehicle management system receives input signals from a multiplicity of sensors and provides commands to a large number of actuators controlling many subsystems. The VMS includes--segregating flight critical and mission critical factors and providing a greater level of back-up or redundancy for the former; centralizing the computation of functions utilized by several subsystems (e.g. air data, rotor speed, etc.); integrating the control of the flight control functions, the compressor control, the rotor conversion control, vibration alleviation by higher harmonic control, engine power anticipation and self-test, all in the same flight control computer (FCC) hardware units. The VMS uses equivalent redundancy techniques to attain quadruple equivalency levels; includes alternate modes of operation and recovery means to back-up any functions which fail; and uses back-up control software for software redundancy.

Quantum proofs can be verified using only single-qubit measurements

NASA Astrophysics Data System (ADS)

Morimae, Tomoyuki; Nagaj, Daniel; Schuch, Norbert

2016-02-01

Quantum Merlin Arthur (QMA) is the class of problems which, though potentially hard to solve, have a quantum solution that can be verified efficiently using a quantum computer. It thus forms a natural quantum version of the classical complexity class NP (and its probabilistic variant MA, Merlin-Arthur games), where the verifier has only classical computational resources. In this paper, we study what happens when we restrict the quantum resources of the verifier to the bare minimum: individual measurements on single qubits received as they come, one by one. We find that despite this grave restriction, it is still possible to soundly verify any problem in QMA for the verifier with the minimum quantum resources possible, without using any quantum memory or multiqubit operations. We provide two independent proofs of this fact, based on measurement-based quantum computation and the local Hamiltonian problem. The former construction also applies to QMA1, i.e., QMA with one-sided error.

Learning the ideal observer for SKE detection tasks by use of convolutional neural networks (Cum Laude Poster Award)

NASA Astrophysics Data System (ADS)

Zhou, Weimin; Anastasio, Mark A.

2018-03-01

It has been advocated that task-based measures of image quality (IQ) should be employed to evaluate and optimize imaging systems. Task-based measures of IQ quantify the performance of an observer on a medically relevant task. The Bayesian Ideal Observer (IO), which employs complete statistical information of the object and noise, achieves the upper limit of the performance for a binary signal classification task. However, computing the IO performance is generally analytically intractable and can be computationally burdensome when Markov-chain Monte Carlo (MCMC) techniques are employed. In this paper, supervised learning with convolutional neural networks (CNNs) is employed to approximate the IO test statistics for a signal-known-exactly and background-known-exactly (SKE/BKE) binary detection task. The receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC) are compared to those produced by the analytically computed IO. The advantages of the proposed supervised learning approach for approximating the IO are demonstrated.

Scheduling algorithms for automatic control systems for technological processes

NASA Astrophysics Data System (ADS)

Chernigovskiy, A. S.; Tsarev, R. Yu; Kapulin, D. V.

2017-01-01

Wide use of automatic process control systems and the usage of high-performance systems containing a number of computers (processors) give opportunities for creation of high-quality and fast production that increases competitiveness of an enterprise. Exact and fast calculations, control computation, and processing of the big data arrays - all of this requires the high level of productivity and, at the same time, minimum time of data handling and result receiving. In order to reach the best time, it is necessary not only to use computing resources optimally, but also to design and develop the software so that time gain will be maximal. For this purpose task (jobs or operations), scheduling techniques for the multi-machine/multiprocessor systems are applied. Some of basic task scheduling methods for the multi-machine process control systems are considered in this paper, their advantages and disadvantages come to light, and also some usage considerations, in case of the software for automatic process control systems developing, are made.

Are computers effective lie detectors? A meta-analysis of linguistic cues to deception.

PubMed

Hauch, Valerie; Blandón-Gitlin, Iris; Masip, Jaume; Sporer, Siegfried L

2015-11-01

This meta-analysis investigates linguistic cues to deception and whether these cues can be detected with computer programs. We integrated operational definitions for 79 cues from 44 studies where software had been used to identify linguistic deception cues. These cues were allocated to six research questions. As expected, the meta-analyses demonstrated that, relative to truth-tellers, liars experienced greater cognitive load, expressed more negative emotions, distanced themselves more from events, expressed fewer sensory-perceptual words, and referred less often to cognitive processes. However, liars were not more uncertain than truth-tellers. These effects were moderated by event type, involvement, emotional valence, intensity of interaction, motivation, and other moderators. Although the overall effect size was small, theory-driven predictions for certain cues received support. These findings not only further our knowledge about the usefulness of linguistic cues to detect deception with computers in applied settings but also elucidate the relationship between language and deception. © 2014 by the Society for Personality and Social Psychology, Inc.

EEG-Based Computer Aided Diagnosis of Autism Spectrum Disorder Using Wavelet, Entropy, and ANN

PubMed Central

AlSharabi, Khalil; Ibrahim, Sutrisno; Alsuwailem, Abdullah

2017-01-01

Autism spectrum disorder (ASD) is a type of neurodevelopmental disorder with core impairments in the social relationships, communication, imagination, or flexibility of thought and restricted repertoire of activity and interest. In this work, a new computer aided diagnosis (CAD) of autism ‎based on electroencephalography (EEG) signal analysis is investigated. The proposed method is based on discrete wavelet transform (DWT), entropy (En), and artificial neural network (ANN). DWT is used to decompose EEG signals into approximation and details coefficients to obtain EEG subbands. The feature vector is constructed by computing Shannon entropy values from each EEG subband. ANN classifies the corresponding EEG signal into normal or autistic based on the extracted features. The experimental results show the effectiveness of the proposed method for assisting autism diagnosis. A receiver operating characteristic (ROC) curve metric is used to quantify the performance of the proposed method. The proposed method obtained promising results tested using real dataset provided by King Abdulaziz Hospital, Jeddah, Saudi Arabia. PMID:28484720

A new 2D segmentation method based on dynamic programming applied to computer aided detection in mammography.

PubMed

Timp, Sheila; Karssemeijer, Nico

2004-05-01

Mass segmentation plays a crucial role in computer-aided diagnosis (CAD) systems for classification of suspicious regions as normal, benign, or malignant. In this article we present a robust and automated segmentation technique--based on dynamic programming--to segment mass lesions from surrounding tissue. In addition, we propose an efficient algorithm to guarantee resulting contours to be closed. The segmentation method based on dynamic programming was quantitatively compared with two other automated segmentation methods (region growing and the discrete contour model) on a dataset of 1210 masses. For each mass an overlap criterion was calculated to determine the similarity with manual segmentation. The mean overlap percentage for dynamic programming was 0.69, for the other two methods 0.60 and 0.59, respectively. The difference in overlap percentage was statistically significant. To study the influence of the segmentation method on the performance of a CAD system two additional experiments were carried out. The first experiment studied the detection performance of the CAD system for the different segmentation methods. Free-response receiver operating characteristics analysis showed that the detection performance was nearly identical for the three segmentation methods. In the second experiment the ability of the classifier to discriminate between malignant and benign lesions was studied. For region based evaluation the area Az under the receiver operating characteristics curve was 0.74 for dynamic programming, 0.72 for the discrete contour model, and 0.67 for region growing. The difference in Az values obtained by the dynamic programming method and region growing was statistically significant. The differences between other methods were not significant.

Time-Resolved C-Arm Computed Tomographic Angiography Derived From Computed Tomographic Perfusion Acquisition: New Capability for One-Stop-Shop Acute Ischemic Stroke Treatment in the Angiosuite.

PubMed

Yang, Pengfei; Niu, Kai; Wu, Yijing; Struffert, Tobias; Dorfler, Arnd; Schafer, Sebastian; Royalty, Kevin; Strother, Charles; Chen, Guang-Hong

2015-12-01

Multimodal imaging using cone beam C-arm computed tomography (CT) may shorten the delay from ictus to revascularization for acute ischemic stroke patients with a large vessel occlusion. Largely because of limited temporal resolution, reconstruction of time-resolved CT angiography (CTA) from these systems has not yielded satisfactory results. We evaluated the image quality and diagnostic value of time-resolved C-arm CTA reconstructed using novel image processing algorithms. Studies were done under an Institutional Review Board approved protocol. Postprocessing of data from 21 C-arm CT dynamic perfusion acquisitions from 17 patients with acute ischemic stroke were done to derive time-resolved C-arm CTA images. Two observers independently evaluated image quality and diagnostic content for each case. ICC and receiver-operating characteristic analysis were performed to evaluate interobserver agreement and diagnostic value of this novel imaging modality. Time-resolved C-arm CTA images were successfully generated from 20 data sets (95.2%, 20/21). Two observers agreed well that the image quality for large cerebral arteries was good but was more limited for small cerebral arteries (distal to M1, A1, and P1). receiver-operating characteristic curves demonstrated excellent diagnostic value for detecting large vessel occlusions (area under the curve=0.987-1). Time-resolved CTAs derived from C-arm CT perfusion acquisitions provide high quality images that allowed accurate diagnosis of large vessel occlusions. Although image quality of smaller arteries in this study was not optimal ongoing modifications of the postprocessing algorithm will likely remove this limitation. Adding time-resolved C-arm CTAs to the capabilities of the angiography suite further enhances its suitability as a one-stop shop for care for patients with acute ischemic stroke. © 2015 American Heart Association, Inc.

Automated analysis of retinal images for detection of referable diabetic retinopathy.

PubMed

Abràmoff, Michael D; Folk, James C; Han, Dennis P; Walker, Jonathan D; Williams, David F; Russell, Stephen R; Massin, Pascale; Cochener, Beatrice; Gain, Philippe; Tang, Li; Lamard, Mathieu; Moga, Daniela C; Quellec, Gwénolé; Niemeijer, Meindert

2013-03-01

The diagnostic accuracy of computer detection programs has been reported to be comparable to that of specialists and expert readers, but no computer detection programs have been validated in an independent cohort using an internationally recognized diabetic retinopathy (DR) standard. To determine the sensitivity and specificity of the Iowa Detection Program (IDP) to detect referable diabetic retinopathy (RDR). In primary care DR clinics in France, from January 1, 2005, through December 31, 2010, patients were photographed consecutively, and retinal color images were graded for retinopathy severity according to the International Clinical Diabetic Retinopathy scale and macular edema by 3 masked independent retinal specialists and regraded with adjudication until consensus. The IDP analyzed the same images at a predetermined and fixed set point. We defined RDR as more than mild nonproliferative retinopathy and/or macular edema. A total of 874 people with diabetes at risk for DR. Sensitivity and specificity of the IDP to detect RDR, area under the receiver operating characteristic curve, sensitivity and specificity of the retinal specialists' readings, and mean interobserver difference (κ). The RDR prevalence was 21.7% (95% CI, 19.0%-24.5%). The IDP sensitivity was 96.8% (95% CI, 94.4%-99.3%) and specificity was 59.4% (95% CI, 55.7%-63.0%), corresponding to 6 of 874 false-negative results (none met treatment criteria). The area under the receiver operating characteristic curve was 0.937 (95% CI, 0.916-0.959). Before adjudication and consensus, the sensitivity/specificity of the retinal specialists were 0.80/0.98, 0.71/1.00, and 0.91/0.95, and the mean intergrader κ was 0.822. The IDP has high sensitivity and specificity to detect RDR. Computer analysis of retinal photographs for DR and automated detection of RDR can be implemented safely into the DR screening pipeline, potentially improving access to screening and health care productivity and reducing visual loss through early treatment.

Augmented Quadruple-Phase Contrast Media Administration and Triphasic Scan Protocol Increases Image Quality at Reduced Radiation Dose During Computed Tomography Urography.

PubMed

Saade, Charbel; Mohamad, May; Kerek, Racha; Hamieh, Nadine; Alsheikh Deeb, Ibrahim; El-Achkar, Bassam; Tamim, Hani; Abdul Razzak, Farah; Haddad, Maurice; Abi-Ghanem, Alain S; El-Merhi, Fadi

The aim of this article was to investigate the opacification of the renal vasculature and the urogenital system during computed tomography urography by using a quadruple-phase contrast media in a triphasic scan protocol. A total of 200 patients with possible urinary tract abnormalities were equally divided between 2 protocols. Protocol A used the conventional single bolus and quadruple-phase scan protocol (pre, arterial, venous, and delayed), retrospectively. Protocol B included a quadruple-phase contrast media injection with a triphasic scan protocol (pre, arterial and combined venous, and delayed), prospectively. Each protocol used 100 mL contrast and saline at a flow rate of 4.5 mL. Attenuation profiles and contrast-to-noise ratio of the renal arteries, veins, and urogenital tract were measured. Effective radiation dose calculation, data analysis by independent sample t test, receiver operating characteristic, and visual grading characteristic analyses were performed. In arterial circulation, only the inferior interlobular arteries in both protocols showed a statistical significance (P < 0.05). Venously, the inferior vena cava, proximal and distal renal veins demonstrated a significant opacification reduction in protocol B than in protocol A (P < 0.001). Protocol B showed a significantly higher mean contrast-to-noise ratio than protocol A (protocol B: 22.68 ± 13.72; protocol A: 14.75 ± 5.76; P < 0.001). Radiation dose was significantly reduced in protocol B (7.38 ± 2.22 mSv) than in protocol A (12.28 ± 2.72 mSv) (P < 0.001). Visual grading characteristic (P < 0.027) and receiver operating characteristic (P < 0.0001) analyses demonstrated a significant preference for protocol B. In computed tomography urography, augmented quadruple-phase contrast media and triphasic scan protocol usage increases the image quality at a reduced radiation dose.

Teaching emergency medical services management skills using a computer simulation exercise.

PubMed

Hubble, Michael W; Richards, Michael E; Wilfong, Denise

2011-02-01

Simulation exercises have long been used to teach management skills in business schools. However, this pedagogical approach has not been reported in emergency medical services (EMS) management education. We sought to develop, deploy, and evaluate a computerized simulation exercise for teaching EMS management skills. Using historical data, a computer simulation model of a regional EMS system was developed. After validation, the simulation was used in an EMS management course. Using historical operational and financial data of the EMS system under study, students designed an EMS system and prepared a budget based on their design. The design of each group was entered into the model that simulated the performance of the EMS system. Students were evaluated on operational and financial performance of their system design and budget accuracy and then surveyed about their experiences with the exercise. The model accurately simulated the performance of the real-world EMS system on which it was based. The exercise helped students identify operational inefficiencies in their system designs and highlighted budget inaccuracies. Most students rated the exercise as moderately or very realistic in ambulance deployment scheduling, budgeting, personnel cost calculations, demand forecasting, system design, and revenue projections. All students indicated the exercise was helpful in gaining a top management perspective, and 89% stated the exercise was helpful in bridging the gap between theory and reality. Preliminary experience with a computer simulator to teach EMS management skills was well received by students in a baccalaureate paramedic program and seems to be a valuable teaching tool. Copyright © 2011 Society for Simulation in Healthcare

Computing angle of arrival of radio signals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borchardt, John J.; Steele, David K.

Various technologies pertaining to computing angle of arrival of radio signals are described. A system that is configured for computing the angle of arrival of a radio signal includes a cylindrical sheath wrapped around a cylindrical object, where the cylindrical sheath acts as a ground plane. The system further includes a plurality of antennas that are positioned about an exterior surface of the cylindrical sheath, and receivers respectively coupled to the antennas. The receivers output measurements pertaining to the radio signal. A processing circuit receives the measurements and computes the angle of arrival of the radio signal based upon themore » measurements.« less

Message passing with a limited number of DMA byte counters

DOEpatents

Blocksome, Michael [Rochester, MN; Chen, Dong [Croton on Hudson, NY; Giampapa, Mark E [Irvington, NY; Heidelberger, Philip [Cortlandt Manor, NY; Kumar, Sameer [White Plains, NY; Parker, Jeffrey J [Rochester, MN

2011-10-04

A method for passing messages in a parallel computer system constructed as a plurality of compute nodes interconnected as a network where each compute node includes a DMA engine but includes only a limited number of byte counters for tracking a number of bytes that are sent or received by the DMA engine, where the byte counters may be used in shared counter or exclusive counter modes of operation. The method includes using rendezvous protocol, a source compute node deterministically sending a request to send (RTS) message with a single RTS descriptor using an exclusive injection counter to track both the RTS message and message data to be sent in association with the RTS message, to a destination compute node such that the RTS descriptor indicates to the destination compute node that the message data will be adaptively routed to the destination node. Using one DMA FIFO at the source compute node, the RTS descriptors are maintained for rendezvous messages destined for the destination compute node to ensure proper message data ordering thereat. Using a reception counter at a DMA engine, the destination compute node tracks reception of the RTS and associated message data and sends a clear to send (CTS) message to the source node in a rendezvous protocol form of a remote get to accept the RTS message and message data and processing the remote get (CTS) by the source compute node DMA engine to provide the message data to be sent.

Image matrix processor for fast multi-dimensional computations

DOEpatents

Roberson, G.P.; Skeate, M.F.

1996-10-15

An apparatus for multi-dimensional computation is disclosed which comprises a computation engine, including a plurality of processing modules. The processing modules are configured in parallel and compute respective contributions to a computed multi-dimensional image of respective two dimensional data sets. A high-speed, parallel access storage system is provided which stores the multi-dimensional data sets, and a switching circuit routes the data among the processing modules in the computation engine and the storage system. A data acquisition port receives the two dimensional data sets representing projections through an image, for reconstruction algorithms such as encountered in computerized tomography. The processing modules include a programmable local host, by which they may be configured to execute a plurality of different types of multi-dimensional algorithms. The processing modules thus include an image manipulation processor, which includes a source cache, a target cache, a coefficient table, and control software for executing image transformation routines using data in the source cache and the coefficient table and loading resulting data in the target cache. The local host processor operates to load the source cache with a two dimensional data set, loads the coefficient table, and transfers resulting data out of the target cache to the storage system, or to another destination. 10 figs.

Is heart rate variability better than routine vital signs for prehospital identification of major hemorrhage?

PubMed

Edla, Shwetha; Reisner, Andrew T; Liu, Jianbo; Convertino, Victor A; Carter, Robert; Reifman, Jaques

2015-02-01

During initial assessment of trauma patients, metrics of heart rate variability (HRV) have been associated with high-risk clinical conditions. Yet, despite numerous studies, the potential of HRV to improve clinical outcomes remains unclear. Our objective was to evaluate whether HRV metrics provide additional diagnostic information, beyond routine vital signs, for making a specific clinical assessment: identification of hemorrhaging patients who receive packed red blood cell (PRBC) transfusion. Adult prehospital trauma patients were analyzed retrospectively, excluding those who lacked a complete set of reliable vital signs and a clean electrocardiogram for computation of HRV metrics. We also excluded patients who did not survive to admission. The primary outcome was hemorrhagic injury plus different PRBC transfusion volumes. We performed multivariate regression analysis using HRV metrics and routine vital signs to test the hypothesis that HRV metrics could improve the diagnosis of hemorrhagic injury plus PRBC transfusion vs routine vital signs alone. As univariate predictors, HRV metrics in a data set of 402 subjects had comparable areas under receiver operating characteristic curves compared with routine vital signs. In multivariate regression models containing routine vital signs, HRV parameters were significant (P<.05) but yielded areas under receiver operating characteristic curves with minimal, nonsignificant improvements (+0.00 to +0.05). A novel diagnostic test should improve diagnostic thinking and allow for better decision making in a significant fraction of cases. Our findings do not support that HRV metrics add value over routine vital signs in terms of prehospital identification of hemorrhaging patients who receive PRBC transfusion. Published by Elsevier Inc.

Stuck in the Shallow End: Education, Race, and Computing. Updated Edition

ERIC Educational Resources Information Center

Margolis, Jane

2017-01-01

The number of African Americans and Latino/as receiving undergraduate and advanced degrees in computer science is disproportionately low. And relatively few African American and Latino/a high school students receive the kind of institutional encouragement, educational opportunities, and preparation needed for them to choose computer science as a…

Wrist display concept demonstration based on 2-in. color AMOLED

NASA Astrophysics Data System (ADS)

Meyer, Frederick M.; Longo, Sam J.; Hopper, Darrel G.

2004-09-01

The wrist watch needs an upgrade. Recent advances in optoelectronics, microelectronics, and communication theory have established a technology base that now make the multimedia Dick Tracy watch attainable during the next decade. As a first step towards stuffing the functionality of an entire personnel computer (PC) and television receiver under a watch face, we have set a goal of providing wrist video capability to warfighters. Commercial sector work on the wrist form factor already includes all the functionality of a personal digital assistant (PDA) and full PC operating system. Our strategy is to leverage these commercial developments. In this paper we describe our use of a 2.2 in. diagonal color active matrix light emitting diode (AMOLED) device as a wrist-mounted display (WMD) to present either full motion video or computer generated graphical image formats.

A survey of signal processing algorithms in brain-computer interfaces based on electrical brain signals.

PubMed

Bashashati, Ali; Fatourechi, Mehrdad; Ward, Rabab K; Birch, Gary E

2007-06-01

Brain-computer interfaces (BCIs) aim at providing a non-muscular channel for sending commands to the external world using the electroencephalographic activity or other electrophysiological measures of the brain function. An essential factor in the successful operation of BCI systems is the methods used to process the brain signals. In the BCI literature, however, there is no comprehensive review of the signal processing techniques used. This work presents the first such comprehensive survey of all BCI designs using electrical signal recordings published prior to January 2006. Detailed results from this survey are presented and discussed. The following key research questions are addressed: (1) what are the key signal processing components of a BCI, (2) what signal processing algorithms have been used in BCIs and (3) which signal processing techniques have received more attention?

TOPICAL REVIEW: A survey of signal processing algorithms in brain computer interfaces based on electrical brain signals

NASA Astrophysics Data System (ADS)

Bashashati, Ali; Fatourechi, Mehrdad; Ward, Rabab K.; Birch, Gary E.

2007-06-01

Brain computer interfaces (BCIs) aim at providing a non-muscular channel for sending commands to the external world using the electroencephalographic activity or other electrophysiological measures of the brain function. An essential factor in the successful operation of BCI systems is the methods used to process the brain signals. In the BCI literature, however, there is no comprehensive review of the signal processing techniques used. This work presents the first such comprehensive survey of all BCI designs using electrical signal recordings published prior to January 2006. Detailed results from this survey are presented and discussed. The following key research questions are addressed: (1) what are the key signal processing components of a BCI, (2) what signal processing algorithms have been used in BCIs and (3) which signal processing techniques have received more attention?

Non-unitary probabilistic quantum computing circuit and method

NASA Technical Reports Server (NTRS)

Williams, Colin P. (Inventor); Gingrich, Robert M. (Inventor)

2009-01-01

A quantum circuit performing quantum computation in a quantum computer. A chosen transformation of an initial n-qubit state is probabilistically obtained. The circuit comprises a unitary quantum operator obtained from a non-unitary quantum operator, operating on an n-qubit state and an ancilla state. When operation on the ancilla state provides a success condition, computation is stopped. When operation on the ancilla state provides a failure condition, computation is performed again on the ancilla state and the n-qubit state obtained in the previous computation, until a success condition is obtained.

Circuit and Method for Communication Over DC Power Line

NASA Technical Reports Server (NTRS)

Krasowski, Michael J.; Prokop, Norman F.

2007-01-01

A circuit and method for transmitting and receiving on-off-keyed (OOK) signals with fractional signal-to-noise ratios uses available high-temperature silicon- on-insulator (SOI) components to move computational, sensing, and actuation abilities closer to high-temperature or high-ionizing radiation environments such as vehicle engine compartments, deep-hole drilling environments, industrial control and monitoring of processes like smelting, and operations near nuclear reactors and in space. This device allows for the networking of multiple, like nodes to each other and to a central processor. It can do this with nothing more than the already in-situ power wiring of the system. The device s microprocessor allows it to make intelligent decisions within the vehicle operational loop and to effect control outputs to its associated actuators. The figure illustrates how each node converts digital serial data to OOK 18-kHz in transmit mode and vice-versa in receive mode; though operations at lower frequencies or up to a megahertz are within reason using this method and these parts. This innovation s technique modulates a DC power bus with millivolt-level signals through a MOSFET (metal oxide semiconductor field effect transistor) and resistor by OOK. It receives and demodulates this signal from the DC power bus through capacitive coupling at high temperature and in high ionizing radiation environments. The demodulation of the OOK signal is accomplished by using an asynchronous quadrature detection technique realized by a quasi-discrete Fourier transform through use of the quadrature components (0 and 90 phases) of the carrier frequency as generated by the microcontroller and as a function of the selected crystal frequency driving its oscillator. The detected signal is rectified using an absolute-value circuit containing no diodes (diodes being non-operational at high temperatures), and only operational amplifiers. The absolute values of the two phases of the received signal are then summed and hard limited (digitized) by comparing them to a reference level and are then input into a microprocessor as a serial bit stream. The quasi-discrete Fourier transform is performed in high-temperature components (operational amplifiers, analog switches, resistors, and capacitors). The demodulated signal is a serial data stream that is input to the UART (universal asynchronous receiver transmitter) receiver pin of the microprocessor. The OOK of the carrier frequency uses the output of the UART pin as an enabling signal that drives the gate of the MOSFET. Logic low bits enable the carrier frequency (realized by using the 0 phase signal from the microcontroller, though either phase may be used) to be DC-coupled to the power supply bus through a current-limiting resistor mounted between the MOSFET drain and the supply rail. The presence of logic lows on the power supply rail is realized by carrier bursts while logic highs are realized by the absence of bursts.

Runtime optimization of an application executing on a parallel computer

DOEpatents

None

2014-11-25

Identifying a collective operation within an application executing on a parallel computer; identifying a call site of the collective operation; determining whether the collective operation is root-based; if the collective operation is not root-based: establishing a tuning session and executing the collective operation in the tuning session; if the collective operation is root-based, determining whether all compute nodes executing the application identified the collective operation at the same call site; if all compute nodes identified the collective operation at the same call site, establishing a tuning session and executing the collective operation in the tuning session; and if all compute nodes executing the application did not identify the collective operation at the same call site, executing the collective operation without establishing a tuning session.

Runtime optimization of an application executing on a parallel computer

DOEpatents

Faraj, Daniel A; Smith, Brian E

2014-11-18

Identifying a collective operation within an application executing on a parallel computer; identifying a call site of the collective operation; determining whether the collective operation is root-based; if the collective operation is not root-based: establishing a tuning session and executing the collective operation in the tuning session; if the collective operation is root-based, determining whether all compute nodes executing the application identified the collective operation at the same call site; if all compute nodes identified the collective operation at the same call site, establishing a tuning session and executing the collective operation in the tuning session; and if all compute nodes executing the application did not identify the collective operation at the same call site, executing the collective operation without establishing a tuning session.

Runtime optimization of an application executing on a parallel computer

DOEpatents

Faraj, Daniel A.; Smith, Brian E.

2013-01-29

Identifying a collective operation within an application executing on a parallel computer; identifying a call site of the collective operation; determining whether the collective operation is root-based; if the collective operation is not root-based: establishing a tuning session and executing the collective operation in the tuning session; if the collective operation is root-based, determining whether all compute nodes executing the application identified the collective operation at the same call site; if all compute nodes identified the collective operation at the same call site, establishing a tuning session and executing the collective operation in the tuning session; and if all compute nodes executing the application did not identify the collective operation at the same call site, executing the collective operation without establishing a tuning session.

Parametric estimates for the receiver operating characteristic curve generalization for non-monotone relationships.

PubMed

Martínez-Camblor, Pablo; Pardo-Fernández, Juan C

2017-01-01

Diagnostic procedures are based on establishing certain conditions and then checking if those conditions are satisfied by a given individual. When the diagnostic procedure is based on a continuous marker, this is equivalent to fix a region or classification subset and then check if the observed value of the marker belongs to that region. Receiver operating characteristic curve is a valuable and popular tool to study and compare the diagnostic ability of a given marker. Besides, the area under the receiver operating characteristic curve is frequently used as an index of the global discrimination ability. This paper revises and widens the scope of the receiver operating characteristic curve definition by setting the classification subsets in which the final decision is based in the spotlight of the analysis. We revise the definition of the receiver operating characteristic curve in terms of particular classes of classification subsets and then focus on a receiver operating characteristic curve generalization for situations in which both low and high values of the marker are associated with more probability of having the studied characteristic. Parametric and non-parametric estimators of the receiver operating characteristic curve generalization are investigated. Monte Carlo studies and real data examples illustrate their practical performance.

Giving and Receiving Advice in Computer-Mediated Peer Response Activities

ERIC Educational Resources Information Center

Tsai, Mei-Hsing; Kinginger, Celeste

2015-01-01

In synchronous computer-mediated contexts, peer-to-peer interaction at the microlevel has received little scrutiny. In applying a conversation analysis approach, this study scrutinizes the precise nature of peer-to-peer advice giving and receiving. In this process, an advice giver can be viewed at certain moments as more competent to evaluate a…

Interior view, looking northeast in computer room OvertheHorizon Backscatter ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior view, looking northeast in computer room - Over-the-Horizon Backscatter Radar Network, Tulelake Radar Site Receive Sector Five Receiver Building, Unnamed Road West of Double Head Road, Tulelake, Siskiyou County, CA

Interior view, looking south in computer room OvertheHorizon Backscatter ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior view, looking south in computer room - Over-the-Horizon Backscatter Radar Network, Tulelake Radar Site Receive Sector Six Receiver Building, Unnamed Road West of Double Head Road, Tulelake, Siskiyou County, CA

Research and investigation of a communication chain on optical fiber with a Fabry-Perot power diode for the automotive industry

NASA Astrophysics Data System (ADS)

Bacis, Irina Bristena; Vasile, Alexandru; Ionescu, Ciprian; Marghescu, Cristina

2016-12-01

The purpose of this paper is to analyze different power devices - emitters of optical flow, from the point of view of optical coupling, emitted optical powers, optical fiber losses and receiver. The research and characterization of the transmission through a power optical system is done using a computer system specialized for the automotive industry. This system/platform can deliver current pulses that are controlled by a computer through a software (it is possible to set different parameters such as pulse repetition frequency, duty cycle, and current intensity). For the experiments a power Fabry Perot 1035 laser diode operating in pulse with μφ 1055 nm, Ith = 40 mA, and Iop =750 mA was used with a single-mode SFM 128 optical fiber and an EM type optical coupler connected through alignment. Two types of measurements were conducted to demonstrate the usefulness of the experimental structure. In the first case the amplitude of the voltage pulses was measured at the output of an optical detector with receiving diode in a built-in amplifier with a 50 kΩ load resistance. In the second stage measurements were conducted to determine the optical power injected in the optical fiber and received at the reception cell of a power meter. Another parameter of optical coupling that can be measured using the experimental structure is irradiation. This parameter is very important to determine the optimum cutting angle of the fiber for continuity welding.

Performing process migration with allreduce operations

DOEpatents

Archer, Charles Jens; Peters, Amanda; Wallenfelt, Brian Paul

2010-12-14

Compute nodes perform allreduce operations that swap processes at nodes. A first allreduce operation generates a first result and uses a first process from a first compute node, a second process from a second compute node, and zeros from other compute nodes. The first compute node replaces the first process with the first result. A second allreduce operation generates a second result and uses the first result from the first compute node, the second process from the second compute node, and zeros from others. The second compute node replaces the second process with the second result, which is the first process. A third allreduce operation generates a third result and uses the first result from first compute node, the second result from the second compute node, and zeros from others. The first compute node replaces the first result with the third result, which is the second process.

Evaluation of Microcomputer-Based Operation and Maintenance Management Systems for Army Water/Wastewater Treatment Plant Operation.

DTIC Science & Technology

1986-07-01

COMPUTER-AIDED OPERATION MANAGEMENT SYSTEM ................. 29 Functions of an Off-Line Computer-Aided Operation Management System Applications of...System Comparisons 85 DISTRIBUTION 5V J. • 0. FIGURES Number Page 1 Hardware Components 21 2 Basic Functions of a Computer-Aided Operation Management System...Plant Visits 26 4 Computer-Aided Operation Management Systems Reviewed for Analysis of Basic Functions 29 5 Progress of Software System Installation and

Cost-Benefit Analysis for ECIA Chapter 1 and State DPPF Programs Comparing Groups Receiving Regular Program Instruction and Groups Receiving Computer Assisted Instruction/Computer Management System (CAI/CMS). 1986-87.

ERIC Educational Resources Information Center

Chamberlain, Ed

A cost benefit study was conducted to determine the effectiveness of a computer assisted instruction/computer management system (CAI/CMS) as an alternative to conventional methods of teaching reading within Chapter 1 and DPPF funded programs of the Columbus (Ohio) Public Schools. The Chapter 1 funded Compensatory Language Experiences and Reading…

Computer-based evaluation of Alzheimer's disease and mild cognitive impairment patients during a picture description task.

PubMed

Hernández-Domínguez, Laura; Ratté, Sylvie; Sierra-Martínez, Gerardo; Roche-Bergua, Andrés

2018-01-01

We present a methodology to automatically evaluate the performance of patients during picture description tasks. Transcriptions and audio recordings of the Cookie Theft picture description task were used. With 25 healthy elderly control (HC) samples and an information coverage measure, we automatically generated a population-specific referent. We then assessed 517 transcriptions (257 Alzheimer's disease [AD], 217 HC, and 43 mild cognitively impaired samples) according to their informativeness and pertinence against this referent. We extracted linguistic and phonetic metrics which previous literature correlated to early-stage AD. We trained two learners to distinguish HCs from cognitively impaired individuals. Our measures significantly ( P  < .001) correlated with the severity of the cognitive impairment and the Mini-Mental State Examination score. The classification sensitivity was 81% (area under the curve of receiver operating characteristics = 0.79) and 85% (area under the curve of receiver operating characteristics = 0.76) between HCs and AD and between HCs and AD and mild cognitively impaired, respectively. An automated assessment of a picture description task could assist clinicians in the detection of early signs of cognitive impairment and AD.

Monitoring and Controlling an Underwater Robotic Arm

NASA Technical Reports Server (NTRS)

Haas, John; Todd, Brian Keith; Woodcock, Larry; Robinson, Fred M.

2009-01-01

The SSRMS Module 1 software is part of a system for monitoring an adaptive, closed-loop control of the motions of a robotic arm in NASA s Neutral Buoyancy Laboratory, where buoyancy in a pool of water is used to simulate the weightlessness of outer space. This software is so named because the robot arm is a replica of the Space Shuttle Remote Manipulator System (SSRMS). This software is distributed, running on remote joint processors (RJPs), each of which is mounted in a hydraulic actuator comprising the joint of the robotic arm and communicating with a poolside processor denoted the Direct Control Rack (DCR). Each RJP executes the feedback joint-motion control algorithm for its joint and communicates with the DCR. The DCR receives joint-angular-velocity commands either locally from an operator or remotely from computers that simulate the flight like SSRMS and perform coordinated motion calculations based on hand-controller inputs. The received commands are checked for validity before they are transmitted to the RJPs. The DCR software generates a display of the statuses of the RJPs for the DCR operator and can shut down the hydraulic pump when excessive joint-angle error or failure of a RJP is detected.

Echo Decorrelation Imaging of Rabbit Liver and VX2 Tumor during In Vivo Ultrasound Ablation.

PubMed

Fosnight, Tyler R; Hooi, Fong Ming; Keil, Ryan D; Ross, Alexander P; Subramanian, Swetha; Akinyi, Teckla G; Killin, Jakob K; Barthe, Peter G; Rudich, Steven M; Ahmad, Syed A; Rao, Marepalli B; Mast, T Douglas

2017-01-01

In open surgical procedures, image-ablate ultrasound arrays performed thermal ablation and imaging on rabbit liver lobes with implanted VX2 tumor. Treatments included unfocused (bulk ultrasound ablation, N = 10) and focused (high-intensity focused ultrasound ablation, N = 13) exposure conditions. Echo decorrelation and integrated backscatter images were formed from pulse-echo data recorded during rest periods after each therapy pulse. Echo decorrelation images were corrected for artifacts using decorrelation measured prior to ablation. Ablation prediction performance was assessed using receiver operating characteristic curves. Results revealed significantly increased echo decorrelation and integrated backscatter in both ablated liver and ablated tumor relative to unablated tissue, with larger differences observed in liver than in tumor. For receiver operating characteristic curves computed from all ablation exposures, both echo decorrelation and integrated backscatter predicted liver and tumor ablation with statistically significant success, and echo decorrelation was significantly better as a predictor of liver ablation. These results indicate echo decorrelation imaging is a successful predictor of local thermal ablation in both normal liver and tumor tissue, with potential for real-time therapy monitoring. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Smooth time-dependent receiver operating characteristic curve estimators.

PubMed

Martínez-Camblor, Pablo; Pardo-Fernández, Juan Carlos

2018-03-01

The receiver operating characteristic curve is a popular graphical method often used to study the diagnostic capacity of continuous (bio)markers. When the considered outcome is a time-dependent variable, two main extensions have been proposed: the cumulative/dynamic receiver operating characteristic curve and the incident/dynamic receiver operating characteristic curve. In both cases, the main problem for developing appropriate estimators is the estimation of the joint distribution of the variables time-to-event and marker. As usual, different approximations lead to different estimators. In this article, the authors explore the use of a bivariate kernel density estimator which accounts for censored observations in the sample and produces smooth estimators of the time-dependent receiver operating characteristic curves. The performance of the resulting cumulative/dynamic and incident/dynamic receiver operating characteristic curves is studied by means of Monte Carlo simulations. Additionally, the influence of the choice of the required smoothing parameters is explored. Finally, two real-applications are considered. An R package is also provided as a complement to this article.

a Computer Simulation Study of Coherent Optical Fibre Communication Systems

NASA Astrophysics Data System (ADS)

Urey, Zafer

Available from UMI in association with The British Library. A computer simulation study of coherent optical fibre communication systems is presented in this thesis. The Wiener process is proposed as the simulation model of laser phase noise and verified to be a good one. This model is included in the simulation experiments along with the other noise sources (i.e shot noise, thermal noise and laser intensity noise) and the models that represent the various waveform processing blocks in a system such as filtering, demodulation, etc. A novel mixed-semianalytical simulation procedure is designed and successfully applied for the estimation of bit error rates as low as 10^{-10 }. In this technique the noise processes and the ISI effects at the decision time are characterized from simulation experiments but the calculation of the probability of error is obtained by numerically integrating the noise statistics over the error region using analytical expressions. Simulation of only 4096 bits is found to give estimates of BER's corresponding to received optical power within 1 dB of the theoretical calculations using this approach. This number is very small when compared with the pure simulation techniques. Hence, the technique is proved to be very efficient in terms of the computation time and the memory requirements. A command driven simulation software which runs on a DEC VAX computer under the UNIX operating system is written by the author and a series of simulation experiments are carried out using this software. In particular, the effects of IF filtering on the performance of PSK heterodyne receivers with synchronous demodulation are examined when both the phase noise and the shot noise are included in the simulations. The BER curves of this receiver are estimated for the first time for various cases of IF filtering using the mixed-semianalytical approach. At a power penalty of 1 dB the IF linewidth requirement of this receiver with the matched filter is estimated to be less than 650 kHz at the modulation rate of 1 Gbps and BER of 10 ^{-9}. The IF linewidth requirement for other IF filtering cases are also estimated. The results are not found to be much different from the matched filter case. Therefore, it is concluded that IF filtering does not have any effect for the reduction of phase noise in PSK heterodyne systems with synchronous demodulation.

Computational and Mathematical Modeling of Coupled Superconducting Quantum Interference Devices

NASA Astrophysics Data System (ADS)

Berggren, Susan Anne Elizabeth

This research focuses on conducting an extensive computational investigation and mathematical analysis into the average voltage response of arrays of Superconducting Quantum Interference Devices (SQUIDs). These arrays will serve as the basis for the development of a sensitive, low noise, significantly lower Size, Weight and Power (SWaP) antenna integrated with Low-Noise Amplifier (LNA) using the SQUID technology. The goal for this antenna is to be capable of meeting all requirements for Guided Missile Destroyers (DDG) 1000 class ships for Information Operations/Signals Intelligence (IO/SIGINT) applications in Very High Frequency/Ultra High Frequency (V/UHF) bands. The device will increase the listening capability of receivers by moving technology into a new regime of energy detection allowing wider band, smaller size, more sensitive, stealthier systems. The smaller size and greater sensitivity will allow for ships to be “de-cluttered” of their current large dishes and devices, replacing everything with fewer and smaller SQUID antenna devices. The fewer devices present on the deck of a ship, the more invisible the ship will be to enemy forces. We invent new arrays of SQUIDs, optimized for signal detection with very high dynamic range and excellent spur-free dynamic range, while maintaining extreme small size (and low radar cross section), wide bandwidth, and environmentally noise limited sensitivity, effectively shifting the bottle neck of receiver systems forever away from the antenna itself deeper into the receiver chain. To accomplish these goals we develop and validate mathematical models for different designs of SQUID arrays and use them to invent a new device and systems design. This design is capable of significantly exceeding, per size weight and power, state-of-the-art receiver system measures of performance, such as bandwidth, sensitivity, dynamic range, and spurious-free dynamic range.

Buffer thermal energy storage for a solar Brayton engine

NASA Technical Reports Server (NTRS)

Strumpf, H. J.; Barr, K. P.

1981-01-01

A study has been completed on the application of latent-heat buffer thermal energy storage to a point-focusing solar receiver equipped with an air Brayton engine. To aid in the study, a computer program was written for complete transient/stead-state Brayton cycle performance. The results indicated that thermal storage can afford a significant decrease in the number of engine shutdowns as compared to operating without thermal storage. However, the number of shutdowns does not continuously decrease as the storage material weight increases. In fact, there appears to be an optimum weight for minimizing the number of shutdowns.

Sensory Interactive Teleoperator Robotic Grasping

NASA Technical Reports Server (NTRS)

Alark, Keli; Lumia, Ron

1997-01-01

As the technological world strives for efficiency, the need for economical equipment that increases operator proficiency in minimal time is fundamental. This system links a CCD camera, a controller and a robotic arm to a computer vision system to provide an alternative method of image analysis. The machine vision system which was employed possesses software tools for acquiring and analyzing images which are received through a CCD camera. After feature extraction on the object in the image was performed, information about the object's location, orientation and distance from the robotic gripper is sent to the robot controller so that the robot can manipulate the object.

Non-invasive detection of the freezing of gait in Parkinson's disease using spectral and wavelet features.

PubMed

Nazarzadeh, Kimia; Arjunan, Sridhar P; Kumar, Dinesh K; Das, Debi Prasad

2016-08-01

In this study, we have analyzed the accelerometer data recorded during gait analysis of Parkinson disease patients for detecting freezing of gait (FOG) episodes. The proposed method filters the recordings for noise reduction of the leg movement changes and computes the wavelet coefficients to detect FOG events. Publicly available FOG database was used and the technique was evaluated using receiver operating characteristic (ROC) analysis. Results show a higher performance of the wavelet feature in discrimination of the FOG events from the background activity when compared with the existing technique.

Using a software-defined computer in teaching the basics of computer architecture and operation

NASA Astrophysics Data System (ADS)

Kosowska, Julia; Mazur, Grzegorz

2017-08-01

The paper describes the concept and implementation of SDC_One software-defined computer designed for experimental and didactic purposes. Equipped with extensive hardware monitoring mechanisms, the device enables the students to monitor the computer's operation on bus transfer cycle or instruction cycle basis, providing the practical illustration of basic aspects of computer's operation. In the paper, we describe the hardware monitoring capabilities of SDC_One and some scenarios of using it in teaching the basics of computer architecture and microprocessor operation.

Utilising handheld computers to monitor and support patients receiving chemotherapy: results of a UK-based feasibility study.

PubMed

Kearney, N; Kidd, L; Miller, M; Sage, M; Khorrami, J; McGee, M; Cassidy, J; Niven, K; Gray, P

2006-07-01

Recent changes in cancer service provision mean that many patients spend a limited time in hospital and therefore experience and must cope with and manage treatment-related side effects at home. Information technology can provide innovative solutions in promoting patient care through information provision, enhancing communication, monitoring treatment-related side effects and promoting self-care. The aim of this feasibility study was to evaluate the acceptability of using handheld computers as a symptom assessment and management tool for patients receiving chemotherapy for cancer. A convenience sample of patients (n = 18) and health professionals (n = 9) at one Scottish cancer centre was recruited. Patients used the handheld computer to record and send daily symptom reports to the cancer centre and receive instant, tailored symptom management advice during two treatment cycles. Both patients' and health professionals' perceptions of the handheld computer system were evaluated at baseline and at the end of the project. Patients believed the handheld computer had improved their symptom management and felt comfortable in using it. The health professionals also found the handheld computer to be helpful in assessing and managing patients' symptoms. This project suggests that a handheld-computer-based symptom management tool is feasible and acceptable to both patients and health professionals in complementing the care of patients receiving chemotherapy.

Performance analysis of a laser propelled interorbital tansfer vehicle

NASA Technical Reports Server (NTRS)

Minovitch, M. A.

1976-01-01

Performance capabilities of a laser-propelled interorbital transfer vehicle receiving propulsive power from one ground-based transmitter was investigated. The laser transmits propulsive energy to the vehicle during successive station fly-overs. By applying a series of these propulsive maneuvers, large payloads can be economically transferred between low earth orbits and synchronous orbits. Operations involving the injection of large payloads onto escape trajectories are also studied. The duration of each successive engine burn must be carefully timed so that the vehicle reappears over the laser station to receive additional propulsive power within the shortest possible time. The analytical solution for determining these time intervals is presented, as is a solution to the problem of determining maximum injection payloads. Parameteric computer analysis based on these optimization studies is presented. The results show that relatively low beam powers, on the order of 50 MW to 60 MW, produce significant performance capabilities.

System and technique for ultrasonic characterization of settling suspensions

DOEpatents

Greenwood, Margaret S [Richland, WA; Panetta, Paul D [Richland, WA; Bamberger, Judith A [Richland, WA; Pappas, Richard A [Richland, WA

2006-11-28

A system for determining properties of settling suspensions includes a settling container, a mixer, and devices for ultrasonic interrogation transverse to the settling direction. A computer system controls operation of the mixer and the interrogation devices and records the response to the interrogating as a function of settling time, which is then used to determine suspension properties. Attenuation versus settling time for dilute suspensions, such as dilute wood pulp suspension, exhibits a peak at different settling times for suspensions having different properties, and the location of this peak is used as one mechanism for characterizing suspensions. Alternatively or in addition, a plurality of ultrasound receivers are arranged at different angles to a common transmitter to receive scattering responses at a variety of angles during particle settling. Angular differences in scattering as a function of settling time are also used to characterize the suspension.

A Scalable, Out-of-Band Diagnostics Architecture for International Space Station Systems Support

NASA Technical Reports Server (NTRS)

Fletcher, Daryl P.; Alena, Rick; Clancy, Daniel (Technical Monitor)

2002-01-01

The computational infrastructure of the International Space Station (ISS) is a dynamic system that supports multiple vehicle subsystems such as Caution and Warning, Electrical Power Systems and Command and Data Handling (C&DH), as well as scientific payloads of varying size and complexity. The dynamic nature of the ISS configuration coupled with the increased demand for payload support places a significant burden on the inherently resource constrained computational infrastructure of the ISS. Onboard system diagnostics applications are hosted on computers that are elements of the avionics network while ground-based diagnostic applications receive only a subset of available telemetry, down-linked via S-band communications. In this paper we propose a scalable, out-of-band diagnostics architecture for ISS systems support that uses a read-only connection for C&DH data acquisition, which provides a lower cost of deployment and maintenance (versus a higher criticality readwrite connection). The diagnostics processing burden is off-loaded from the avionics network to elements of the on-board LAN that have a lower overall cost of operation and increased computational capacity. A superset of diagnostic data, richer in content than the configured telemetry, is made available to Advanced Diagnostic System (ADS) clients running on wireless handheld devices, affording the crew greater mobility for troubleshooting and providing improved insight into vehicle state. The superset of diagnostic data is made available to the ground in near real-time via an out-of band downlink, providing a high level of fidelity between vehicle state and test, training and operational facilities on the ground.

Reducing power consumption while synchronizing a plurality of compute nodes during execution of a parallel application

DOEpatents

Archer, Charles J [Rochester, MN; Blocksome, Michael A [Rochester, MN; Peters, Amanda A [Rochester, MN; Ratterman, Joseph D [Rochester, MN; Smith, Brian E [Rochester, MN

2012-01-10

Methods, apparatus, and products are disclosed for reducing power consumption while synchronizing a plurality of compute nodes during execution of a parallel application that include: beginning, by each compute node, performance of a blocking operation specified by the parallel application, each compute node beginning the blocking operation asynchronously with respect to the other compute nodes; reducing, for each compute node, power to one or more hardware components of that compute node in response to that compute node beginning the performance of the blocking operation; and restoring, for each compute node, the power to the hardware components having power reduced in response to all of the compute nodes beginning the performance of the blocking operation.

Reducing power consumption while synchronizing a plurality of compute nodes during execution of a parallel application

DOEpatents

Archer, Charles J [Rochester, MN; Blocksome, Michael A [Rochester, MN; Peters, Amanda E [Cambridge, MA; Ratterman, Joseph D [Rochester, MN; Smith, Brian E [Rochester, MN

2012-04-17

Methods, apparatus, and products are disclosed for reducing power consumption while synchronizing a plurality of compute nodes during execution of a parallel application that include: beginning, by each compute node, performance of a blocking operation specified by the parallel application, each compute node beginning the blocking operation asynchronously with respect to the other compute nodes; reducing, for each compute node, power to one or more hardware components of that compute node in response to that compute node beginning the performance of the blocking operation; and restoring, for each compute node, the power to the hardware components having power reduced in response to all of the compute nodes beginning the performance of the blocking operation.

A computer program for calculation of approximate embryo/fetus radiation dose in nuclear medicine applications.

PubMed

Bayram, Tuncay; Sönmez, Bircan

2012-04-01

In this study, we aimed to make a computer program that calculates approximate radiation dose received by embryo/fetus in nuclear medicine applications. Radiation dose values per MBq-1 received by embryo/fetus in nuclear medicine applications were gathered from literature for various stages of pregnancy. These values were embedded in the computer code, which was written in Fortran 90 program language. The computer program called nmfdose covers almost all radiopharmaceuticals used in nuclear medicine applications. Approximate radiation dose received by embryo/fetus can be calculated easily at a few steps using this computer program. Although there are some constraints on using the program for some special cases, nmfdose is useful and it provides practical solution for calculation of approximate dose to embryo/fetus in nuclear medicine applications. None declared.

Non-extracorporeal circulation for coronary artery bypass graft surgery is more beneficial than extracorporeal circulation.

PubMed

Yang, F-Y; Bao, Y-Z; Liu, F-S; Zhu, Y-C; Zheng, J; Zhang, J-H; Zheng, X-F; Wei, G-C

2015-04-01

The objective of this study was to compare coronary artery bypass graft (CABG) surgery with non-extracorporeal vs. extracorporeal circulation. The study outcomes included operative time, number of graft vessels, pulmonary infection rates, and systemic inflammatory markers. 96 patients received selective CABG, either with non-extracorporeal (study group; n = 48) or extracorporeal circulation (control group; n = 48). Operative time, pulmonary infection rates, and blood levels of inflammatory markers TNF-α, IL-6, and IL-8 before and 4, 24, and 48 hours after the surgery were quantified. Graft vessels were quantified using computed tomography. Operative time was significantly shorter in study group (4.58 ± 0.91 vs. 5.36 ± 1.12 hours in control group; p < 0.05). The number of graft vessels and pulmonary infection rates were comparable between both techniques. However, systemic inflammatory markers were significantly (p < 0.05) lower in study group at 4 and, partly, 24 hours after the surgery. Extracorporeal circulation prolongs operation and can aggravate systemic inflammatory response. Therefore, CABG with non-extracorporeal circulation offers more beneficial outcomes.

Wireless Sensor Node for Autonomous Monitoring and Alerts in Remote Environments

NASA Technical Reports Server (NTRS)

Panangadan, Anand V. (Inventor); Monacos, Steve P. (Inventor)

2015-01-01

A method, apparatus, system, and computer program products provides personal alert and tracking capabilities using one or more nodes. Each node includes radio transceiver chips operating at different frequency ranges, a power amplifier, sensors, a display, and embedded software. The chips enable the node to operate as either a mobile sensor node or a relay base station node while providing a long distance relay link between nodes. The power amplifier enables a line-of-sight communication between the one or more nodes. The sensors provide a GPS signal, temperature, and accelerometer information (used to trigger an alert condition). The embedded software captures and processes the sensor information, provides a multi-hop packet routing protocol to relay the sensor information to and receive alert information from a command center, and to display the alert information on the display.

MHSS: a material handling system simulator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pomernacki, L.; Hollstien, R.B.

1976-04-07

A Material Handling System Simulator (MHSS) program is described that provides specialized functional blocks for modeling and simulation of nuclear material handling systems. Models of nuclear fuel fabrication plants may be built using functional blocks that simulate material receiving, storage, transport, inventory, processing, and shipping operations as well as the control and reporting tasks of operators or on-line computers. Blocks are also provided that allow the user to observe and gather statistical information on the dynamic behavior of simulated plants over single or replicated runs. Although it is currently being developed for the nuclear materials handling application, MHSS can bemore » adapted to other industries in which material accountability is important. In this paper, emphasis is on the simulation methodology of the MHSS program with application to the nuclear material safeguards problem. (auth)« less

Synchronized computational architecture for generalized bilateral control of robot arms

NASA Technical Reports Server (NTRS)

Szakaly, Zoltan F. (Inventor)

1991-01-01

A master six degree of freedom Force Reflecting Hand Controller (FRHC) is available at a master site where a received image displays, in essentially real time, a remote robotic manipulator which is being controlled in the corresponding six degree freedom by command signals which are transmitted to the remote site in accordance with the movement of the FRHC at the master site. Software is user-initiated at the master site in order to establish the basic system conditions, and then a physical movement of the FRHC in Cartesean space is reflected at the master site by six absolute numbers that are sensed, translated and computed as a difference signal relative to the earlier position. The change in position is then transmitted in that differential signal form over a high speed synchronized bilateral communication channel which simultaneously returns robot-sensed response information to the master site as forces applied to the FRHC so that the FRHC reflects the feel of what is taking place at the remote site. A system wide clock rate is selected at a sufficiently high rate that the operator at the master site experiences the Force Reflecting operation in real time.

Automatic Gleason grading of prostate cancer using quantitative phase imaging and machine learning

NASA Astrophysics Data System (ADS)

Nguyen, Tan H.; Sridharan, Shamira; Macias, Virgilia; Kajdacsy-Balla, Andre; Melamed, Jonathan; Do, Minh N.; Popescu, Gabriel

2017-03-01

We present an approach for automatic diagnosis of tissue biopsies. Our methodology consists of a quantitative phase imaging tissue scanner and machine learning algorithms to process these data. We illustrate the performance by automatic Gleason grading of prostate specimens. The imaging system operates on the principle of interferometry and, as a result, reports on the nanoscale architecture of the unlabeled specimen. We use these data to train a random forest classifier to learn textural behaviors of prostate samples and classify each pixel in the image into different classes. Automatic diagnosis results were computed from the segmented regions. By combining morphological features with quantitative information from the glands and stroma, logistic regression was used to discriminate regions with Gleason grade 3 versus grade 4 cancer in prostatectomy tissue. The overall accuracy of this classification derived from a receiver operating curve was 82%, which is in the range of human error when interobserver variability is considered. We anticipate that our approach will provide a clinically objective and quantitative metric for Gleason grading, allowing us to corroborate results across instruments and laboratories and feed the computer algorithms for improved accuracy.

Modeling Radiative Heat Transfer and Turbulence-Radiation Interactions in Engines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paul, Chandan; Sircar, Arpan; Ferreyro-Fernandez, Sebastian

Detailed radiation modelling in piston engines has received relatively little attention to date. Recently, it is being revisited in light of current trends towards higher operating pressures and higher levels of exhaust-gas recirculation, both of which enhance molecular gas radiation. Advanced high-efficiency engines also are expected to function closer to the limits of stable operation, where even small perturbations to the energy balance can have a large influence on system behavior. Here several different spectral radiation property models and radiative transfer equation (RTE) solvers have been implemented in an OpenFOAM-based engine CFD code, and simulations have been performed for amore » full-load (peak pressure ~200 bar) heavy-duty diesel engine. Differences in computed temperature fields, NO and soot levels, and wall heat transfer rates are shown for different combinations of spectral models and RTE solvers. The relative importance of molecular gas radiation versus soot radiation is examined. And the influence of turbulence-radiation interactions is determined by comparing results obtained using local mean values of composition and temperature to compute radiative emission and absorption with those obtained using a particle-based transported probability density function method.« less

Mexican Space Weather Service (SCiESMEX)

NASA Astrophysics Data System (ADS)

Gonzalez-Esparza, J. A.; De la Luz, V.; Corona-Romero, P.; Mejia-Ambriz, J. C.; Gonzalez, L. X.; Sergeeva, M. A.; Romero-Hernandez, E.; Aguilar-Rodriguez, E.

2017-01-01

Legislative modifications of the General Civil Protection Law in Mexico in 2014 included specific references to space hazards and space weather phenomena. The legislation is consistent with United Nations promotion of international engagement and cooperation on space weather awareness, studies, and monitoring. These internal and external conditions motivated the creation of a space weather service in Mexico. The Mexican Space Weather Service (SCiESMEX in Spanish) (www.sciesmex.unam.mx) was initiated in October 2014 and is operated by the Institute of Geophysics at the Universidad Nacional Autonoma de Mexico (UNAM). SCiESMEX became a Regional Warning Center of the International Space Environment Services (ISES) in June 2015. We present the characteristics of the service, some products, and the initial actions for developing a space weather strategy in Mexico. The service operates a computing infrastructure including a web application, data repository, and a high-performance computing server to run numerical models. SCiESMEX uses data of the ground-based instrumental network of the National Space Weather Laboratory (LANCE), covering solar radio burst emissions, solar wind and interplanetary disturbances (by interplanetary scintillation observations), geomagnetic measurements, and analysis of the total electron content (TEC) of the ionosphere (by employing data from local networks of GPS receiver stations).

A new assessment method of pHEMT models by comparing relative errors of drain current and its derivatives up to the third order

NASA Astrophysics Data System (ADS)

Dobeš, Josef; Grábner, Martin; Puričer, Pavel; Vejražka, František; Míchal, Jan; Popp, Jakub

2017-05-01

Nowadays, there exist relatively precise pHEMT models available for computer-aided design, and they are frequently compared to each other. However, such comparisons are mostly based on absolute errors of drain-current equations and their derivatives. In the paper, a novel method is suggested based on relative root-mean-square errors of both drain current and its derivatives up to the third order. Moreover, the relative errors are subsequently relativized to the best model in each category to further clarify obtained accuracies of both drain current and its derivatives. Furthermore, one our older and two newly suggested models are also included in comparison with the traditionally precise Ahmed, TOM-2 and Materka ones. The assessment is performed using measured characteristics of a pHEMT operating up to 110 GHz. Finally, a usability of the proposed models including the higher-order derivatives is illustrated using s-parameters analysis and measurement at more operating points as well as computation and measurement of IP3 points of a low-noise amplifier of a multi-constellation satellite navigation receiver with ATF-54143 pHEMT.

Processing AIRS Scientific Data Through Level 2

NASA Technical Reports Server (NTRS)

Oliphant, Robert; Lee, Sung-Yung; Chahine, Moustafa; Susskind, Joel; arnet, Christopher; McMillin, Larry; Goldberg, Mitchell; Blaisdell, John; Rosenkranz, Philip; Strow, Larrabee

2007-01-01

The Atmospheric Infrared Spectrometer (AIRS) Science Processing System (SPS) is a collection of computer programs, denoted product generation executives (PGEs), for processing the readings of the AIRS suite of infrared and microwave instruments orbiting the Earth aboard NASA s Aqua spacecraft. AIRS SPS at an earlier stage of development was described in "Initial Processing of Infrared Spectral Data' (NPO-35243), NASA Tech Briefs, Vol. 28, No. 11 (November 2004), page 39. To recapitulate: Starting from level 0 (representing raw AIRS data), the PGEs and their data products are denoted by alphanumeric labels (1A, 1B, and 2) that signify the successive stages of processing. The cited prior article described processing through level 1B (the level-2 PGEs were not yet operational). The level-2 PGEs, which are now operational, receive packages of level-1B geolocated radiance data products and produce such geolocated geophysical atmospheric data products such as temperature and humidity profiles. The process of computing these geophysical data products is denoted "retrieval" and is quite complex. The main steps of the process are denoted microwave-only retrieval, cloud detection and cloud clearing, regression, full retrieval, and rapid transmittance algorithm.

MW 08-multi-beam air and surface surveillance radar

NASA Astrophysics Data System (ADS)

1989-09-01

Signal of the Netherlands has developed and is marketing the MW 08, a 3-D radar to be used for short to medium range surveillance, target acquisition, and tracking. MW 08 is a fully automated detecting and tracking radar. It is designed to counter threats from aircraft and low flying antiship missiles. It can also deal with the high level missile threat. MW 08 operates in the 5 cm band using one antenna for both transmitting and receiving. The antenna is an array, consisting of 8 stripline antennas. The received radar energy is processed by 8 receiver channels. These channels come together in the beam forming network, in which 8 virtual beams are formed. From this beam pattern, 6 beams are used for the elevation coverage of 0-70 degrees. MW 08's output signals of the beam former are further handled by FFT and plot processors for target speed information, clutter rejection, and jamming suppression. A general purpose computer handles target track initiation, and tracking. Tracking data are transferred to the command and control systems with 3-D target information for fastest possible lockon.

Recent advances and plans in processing and geocoding of SAR data at the DFD

NASA Technical Reports Server (NTRS)

Noack, W.

1993-01-01

Because of the needs of future projects like ENVISAT and the experiences made with the current operational ERS-1 facilities, a radical change in the synthetic aperture radar (SAR) processing scenarios can be predicted for the next years. At the German PAF several new developments were initialized which are driven mainly either by user needs or by system and operational constraints ('lessons learned'). At the end there will be a major simplification and uniformation of all used computer systems. Especially the following changes are likely to be implemented at the German PAF: transcription before archiving, processing of all standard products with high throughput directly at the receiving stations, processing of special 'high-valued' products at the PAF, usage of a single type of processor hardware, implementation of a large and fast on-line data archive, and improved and unified fast data network between the processing and archiving facilities. A short description of the current operational SAR facilities as well as the future implementations are given.

LWPC: Long Wavelength Propagation Capability

NASA Astrophysics Data System (ADS)

U. S. Navy; Ferguson, J. A.; Hutchins, Michael

2018-03-01

Long Wavelength Propagation Capability (LWPC), written as a collection of separate programs that perform unique actions, generates geographical maps of signal availability for coverage analysis. The program makes it easy to set up these displays by automating most of the required steps. The user specifies the transmitter location and frequency, the orientation of the transmitting and receiving antennae, and the boundaries of the operating area. The program automatically selects paths along geographic bearing angles to ensure that the operating area is fully covered. The diurnal conditions and other relevant geophysical parameters are then determined along each path. After the mode parameters along each path are determined, the signal strength along each path is computed. The signal strength along the paths is then interpolated onto a grid overlying the operating area. The final grid of signal strength values is used to display the signal-strength in a geographic display. The LWPC uses character strings to control programs and to specify options. The control strings have the same meaning and use among all the programs.

System and method of self-properties for an autonomous and automatic computer environment

NASA Technical Reports Server (NTRS)

Sterritt, Roy (Inventor); Hinchey, Michael G. (Inventor)

2010-01-01

Systems, methods and apparatus are provided through which in some embodiments self health/urgency data and environment health/urgency data may be transmitted externally from an autonomic element. Other embodiments may include transmitting the self health/urgency data and environment health/urgency data together on a regular basis similar to the lub-dub of a heartbeat. Yet other embodiments may include a method for managing a system based on the functioning state and operating status of the system, wherein the method may include processing received signals from the system indicative of the functioning state and the operating status to obtain an analysis of the condition of the system, generating one or more stay alive signals based on the functioning status and the operating state of the system, transmitting the stay-alive signal, transmitting self health/urgency data, and transmitting environment health/urgency data. Still other embodiments may include an autonomic element that includes a self monitor, a self adjuster, an environment monitor, and an autonomic manager.

10-MWe solar-thermal central-receiver pilot plant. Operating and maintenance manual

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1979-08-01

Information required to perform the initial program loading and operation of the Heliostat Array Controller (HAC) is provided. Operating activities are described as required for heliostat control. All computer console command steps, from power up to power down are described. Detailed steps are provided to wake up the system and direct heliostat beams to standby, on target, standby to stow and power down. Maintenance requirements (preventive and corrective), reparability (reparable - non-reparable decisions), spares identification, spares storage location, replacement levels, replacement location and repair location are established. Individual system breakdown block diagrams are provided for each system/assembly/subassembly. Maintenance and repairmore » description sheets are provided for each maintenance significant item. The manual provides support of the following equipment: (a) helostat assembly; (b) heliostat control assembly; and (c) maintenance and installation equipment. The safety requirements for the operating and maintenance functions are established. These procedures will assist in eliminating or controlling the accident potentials caused by human error, environment, or component malfunctions or interactions that could result in major injury or fatality to operating or visiting personnel, or damage to subsystem components or support equipment. These procedures are for normal and test operating conditions and emergency situations, and apply to all Martin Marietta Corporation, governmental, operating and visitor personnel. (LEW)« less

The expanded role of computers in Space Station Freedom real-time operations

NASA Technical Reports Server (NTRS)

Crawford, R. Paul; Cannon, Kathleen V.

1990-01-01

The challenges that NASA and its international partners face in their real-time operation of the Space Station Freedom necessitate an increased role on the part of computers. In building the operational concepts concerning the role of the computer, the Space Station program is using lessons learned experience from past programs, knowledge of the needs of future space programs, and technical advances in the computer industry. The computer is expected to contribute most significantly in real-time operations by forming a versatile operating architecture, a responsive operations tool set, and an environment that promotes effective and efficient utilization of Space Station Freedom resources.

Computation of transmitted and received B1 fields in magnetic resonance imaging.

PubMed

Milles, Julien; Zhu, Yue Min; Chen, Nan-Kuei; Panych, Lawrence P; Gimenez, Gérard; Guttmann, Charles R G

2006-05-01

Computation of B1 fields is a key issue for determination and correction of intensity nonuniformity in magnetic resonance images. This paper presents a new method for computing transmitted and received B1 fields. Our method combines a modified MRI acquisition protocol and an estimation technique based on the Levenberg-Marquardt algorithm and spatial filtering. It enables accurate estimation of transmitted and received B1 fields for both homogeneous and heterogeneous objects. The method is validated using numerical simulations and experimental data from phantom and human scans. The experimental results are in agreement with theoretical expectations.

New Severity Indices for Quantifying Single-suture Metopic Craniosynostosis

PubMed Central

Ruiz-Correa, Salvador; Starr, Jacqueline R.; Lin, H. Jill; Kapp-Simon, Kathleen A.; Sze, Raymond W.; Ellenbogen, Richard G.; Speltz, Matthew L.; Cunningham, Michael L.

2012-01-01

OBJECTIVE To describe novel severity indices with which to quantify severity of trigonocephaly malformation in children diagnosed with isolated metopic synostosis. METHODS Computed tomographic scans of the cranium were obtained from 38 infants diagnosed with isolated metopic synostosis and 53 age-matched control patients. Volumetric reformations of the cranium were used to trace two-dimensional planes defined by the cranium-base plane and well-defined brain landmarks. For each patient, novel trigonocephaly severity indices (TSI) were computed from outline cranium shapes on each of these planes. The metopic severity index based on measurements of interlandmark distances was also computed and a receiver operating characteristic analysis used to compare the accuracy of classification based on TSIs versus that based on the metopic severity index. RESULTS The proposed TSIs are a sensitive measure of trigonocephaly malformation that can provide a classification accuracy of 96% with a specificity of 95%, in contrast with 82% of the metopic severity index at the same specificity level. CONCLUSIONS We completed exploratory analysis of outline-based severity measurements computed from computed tomographic image planes of the cranium. These TSIs enable quantitative analysis of cranium features in isolated metopic synostosis that may not be accurately detected by analytic tools derived from a sparse set of traditional interlandmark and semilandmark distances. PMID:18797362

Treecode with a Special-Purpose Processor

NASA Astrophysics Data System (ADS)

Makino, Junichiro

1991-08-01

We describe an implementation of the modified Barnes-Hut tree algorithm for a gravitational N-body calculation on a GRAPE (GRAvity PipE) backend processor. GRAPE is a special-purpose computer for N-body calculations. It receives the positions and masses of particles from a host computer and then calculates the gravitational force at each coordinate specified by the host. To use this GRAPE processor with the hierarchical tree algorithm, the host computer must maintain a list of all nodes that exert force on a particle. If we create this list for each particle of the system at each timestep, the number of floating-point operations on the host and that on GRAPE would become comparable, and the increased speed obtained by using GRAPE would be small. In our modified algorithm, we create a list of nodes for many particles. Thus, the amount of the work required of the host is significantly reduced. This algorithm was originally developed by Barnes in order to vectorize the force calculation on a Cyber 205. With this algorithm, the computing time of the force calculation becomes comparable to that of the tree construction, if the GRAPE backend processor is sufficiently fast. The obtained speed-up factor is 30 to 50 for a RISC-based host computer and GRAPE-1A with a peak speed of 240 Mflops.

GPU-based prompt gamma ray imaging from boron neutron capture therapy.

PubMed

Yoon, Do-Kun; Jung, Joo-Young; Jo Hong, Key; Sil Lee, Keum; Suk Suh, Tae

2015-01-01

The purpose of this research is to perform the fast reconstruction of a prompt gamma ray image using a graphics processing unit (GPU) computation from boron neutron capture therapy (BNCT) simulations. To evaluate the accuracy of the reconstructed image, a phantom including four boron uptake regions (BURs) was used in the simulation. After the Monte Carlo simulation of the BNCT, the modified ordered subset expectation maximization reconstruction algorithm using the GPU computation was used to reconstruct the images with fewer projections. The computation times for image reconstruction were compared between the GPU and the central processing unit (CPU). Also, the accuracy of the reconstructed image was evaluated by a receiver operating characteristic (ROC) curve analysis. The image reconstruction time using the GPU was 196 times faster than the conventional reconstruction time using the CPU. For the four BURs, the area under curve values from the ROC curve were 0.6726 (A-region), 0.6890 (B-region), 0.7384 (C-region), and 0.8009 (D-region). The tomographic image using the prompt gamma ray event from the BNCT simulation was acquired using the GPU computation in order to perform a fast reconstruction during treatment. The authors verified the feasibility of the prompt gamma ray image reconstruction using the GPU computation for BNCT simulations.

Local area network with fault-checking, priorities, and redundant backup

NASA Technical Reports Server (NTRS)

Morales, Sergio (Inventor); Friedman, Gary L. (Inventor)

1989-01-01

This invention is a redundant error detecting and correcting local area networked computer system having a plurality of nodes each including a network connector board within the node for connecting to an interfacing transceiver operably attached to a network cable. There is a first network cable disposed along a path to interconnect the nodes. The first network cable includes a plurality of first interfacing transceivers attached thereto. A second network cable is disposed in parallel with the first cable and, in like manner, includes a plurality of second interfacing transceivers attached thereto. There are a plurality of three position switches each having a signal input, three outputs for individual selective connection to the input, and a control input for receiving signals designating which of the outputs is to be connected to the signal input. Each of the switches includes means for designating a response address for responding to addressed signals appearing at the control input and each of the switches further has its signal input connected to a respective one of the input/output lines from the nodes. Also, one of the three outputs is connected to a repective one of the plurality of first interfacing transceivers. There is master switch control means having an output connected to the control inputs of the plurality of three position switches and an input for receiving directive signals for outputting addressed switch position signals to the three position switches as well as monitor and control computer means having a pair of network connector boards therein connected to respective ones of one of the first interfacing transceivers and one of the second interfacing transceivers and an output connected to the input of the master switch means for monitoring the status of the networked computer system by sending messages to the nodes and receiving and verifying messages therefrom and for sending control signals to the master switch to cause the master switch to cause respective ones of the nodes to use a desired one of the first and second cables for transmitting and receiving messages and for disconnecting desired ones of the nodes from both cables.

Investigative clinical study on prostate cancer part IV: exploring functional relationships of total testosterone predicting free testosterone and total prostate-specific antigen in operated prostate cancer patients.

PubMed

Porcaro, Antonio B; Petrozziello, Aldo; Migliorini, Filippo; Lacola, Vincenzo; Romano, Mario; Sava, Teodoro; Ghimenton, Claudio; Caruso, Beatrice; Zecchini Antoniolli, Stefano; Rubilotta, Emanuele; Monaco, Carmelo; Comunale, Luigi

2011-01-01

To explore, in operated prostate cancer patients, functional relationships of total testosterone (tt) predicting free testosterone (ft) and total PSA. 128 operated prostate cancer patients were simultaneously investigated for tt, ft and PSA before surgery. Patients were not receiving 5α-reductase inhibitors, LH-releasing hormone analogues and testosterone replacement treatment. Scatter plots including ft and PSA versus tt were computed in order to assess the functional relationship of the variables. Linear regression analysis of tt predicting ft and PSA was computed. tt was a significant predictor of the response variable (ft) and different subsets of the patient population were assessed according to the ft to tt ratio. PSA was related to tt according to a nonlinear law. tt was a significant predictor of PSA according to an inversely nonlinear law and different significant clusters of the patient population were assessed according to the different constant of proportionality computed from experimental data. In our prostate cancer population, ft was significantly predicted by tt according to a linear law, and the ft/tt ratio was a significant parameter for assessing the different clusters. Also, tt was a significant variable predicting PSA by a nonlinear law and different clusters of the patient population were assessed by the different constants of proportionality. As a theory, we explain the nonlinear relation of tt in predicting PSA as follows: (a) the number of androgen-independent prostate cancer cells increases as tumor volume and PSA serum levels rise, (b) the prevalence of androgen-independent cells producing a substance which inhibits serum LH, and (c) as a result lower levels of serum tt are detected. Copyright © 2011 S. Karger AG, Basel.

Bad data packet capture device

DOEpatents

Chen, Dong; Gara, Alan; Heidelberger, Philip; Vranas, Pavlos

2010-04-20

An apparatus and method for capturing data packets for analysis on a network computing system includes a sending node and a receiving node connected by a bi-directional communication link. The sending node sends a data transmission to the receiving node on the bi-directional communication link, and the receiving node receives the data transmission and verifies the data transmission to determine valid data and invalid data and verify retransmissions of invalid data as corresponding valid data. A memory device communicates with the receiving node for storing the invalid data and the corresponding valid data. A computing node communicates with the memory device and receives and performs an analysis of the invalid data and the corresponding valid data received from the memory device.

Coquina Elementary students enjoy gift of computers

NASA Technical Reports Server (NTRS)

1999-01-01

Children at Coquina Elementary School, Titusville, Fla., 'practice' using a computer keyboard, part of equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. Ksc employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated.

Coquina Elementary students enjoy gift of computers

NASA Technical Reports Server (NTRS)

1999-01-01

Children at Coquina Elementary School, Titusville, Fla., look with curiosity at the wrapped computer equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. Ksc employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated.

Audubon Elementary students enjoy gift of computers

NASA Technical Reports Server (NTRS)

1999-01-01

Children at Audubon Elementary School, Merritt Island, Fla., eagerly unwrap computer equipment donated by Kennedy Space Center. Audubon is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year- long project. Ksc employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated.

Coquina Elementary students enjoy gift of computers

NASA Technical Reports Server (NTRS)

1999-01-01

Children at Coquina Elementary School, Titusville, Fla., eagerly tear into the wrapped computer equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year- long project. Ksc employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated.

Coquina Elementary students enjoy gift of computers

NASA Technical Reports Server (NTRS)

1999-01-01

Children at Coquina Elementary School, Titusville, Fla., excitedly tear into the wrapped computer equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. Ksc employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated.

Application of computer-aided diagnosis (CAD) in MR-mammography (MRM): do we really need whole lesion time curve distribution analysis?

PubMed

Baltzer, Pascal Andreas Thomas; Renz, Diane M; Kullnig, Petra E; Gajda, Mieczyslaw; Camara, Oumar; Kaiser, Werner A

2009-04-01

The identification of the most suspect enhancing part of a lesion is regarded as a major diagnostic criterion in dynamic magnetic resonance mammography. Computer-aided diagnosis (CAD) software allows the semi-automatic analysis of the kinetic characteristics of complete enhancing lesions, providing additional information about lesion vasculature. The diagnostic value of this information has not yet been quantified. Consecutive patients from routine diagnostic studies (1.5 T, 0.1 mmol gadopentetate dimeglumine, dynamic gradient-echo sequences at 1-minute intervals) were analyzed prospectively using CAD. Dynamic sequences were processed and reduced to a parametric map. Curve types were classified by initial signal increase (not significant, intermediate, and strong) and the delayed time course of signal intensity (continuous, plateau, and washout). Lesion enhancement was measured using CAD. The most suspect curve, the curve-type distribution percentage, and combined dynamic data were compared. Statistical analysis included logistic regression analysis and receiver-operating characteristic analysis. Fifty-one patients with 46 malignant and 44 benign lesions were enrolled. On receiver-operating characteristic analysis, the most suspect curve showed diagnostic accuracy of 76.7 +/- 5%. In comparison, the curve-type distribution percentage demonstrated accuracy of 80.2 +/- 4.9%. Combined dynamic data had the highest diagnostic accuracy (84.3 +/- 4.2%). These differences did not achieve statistical significance. With appropriate cutoff values, sensitivity and specificity, respectively, were found to be 80.4% and 72.7% for the most suspect curve, 76.1% and 83.6% for the curve-type distribution percentage, and 78.3% and 84.5% for both parameters. The integration of whole-lesion dynamic data tends to improve specificity. However, no statistical significance backs up this finding.

Development of an integrated digital hand grip dynamometer and norm of hand grip strength.

PubMed

Chang, Ho; Chen, Chih-Hao; Huang, Tung-Sun; Tai, Chun-Yen

2015-01-01

This study designs and fabricates a novel integrated digital hand grip dynamometer and analyzes collected grip strength data. The dynamometer directly stores collected data in a computer, unlike those on the market that cannot directly store information. A strain gauge load cell is used as a force sensor. The dynamometer is designed to maximize ergonomics. Excitation voltage of the load cell is 5 V, and a 9 V battery supplies power to its circuit. The signal receiver is National Instruments (NI) data acquisition (DAQ) card that transmits signals to the computer. The operation system is designed using LabView. This study assesses the correlation between variables of collected data. The correlation coefficients for height, weight and palm length were 0.793, 0.609 and 0.715, respectively, indicating that variables were moderately to strongly correlate with grip strength.

Signaling completion of a message transfer from an origin compute node to a target compute node

DOEpatents

Blocksome, Michael A [Rochester, MN; Parker, Jeffrey J [Rochester, MN

2011-05-24

Signaling completion of a message transfer from an origin node to a target node includes: sending, by an origin DMA engine, an RTS message, the RTS message specifying an application message for transfer to the target node from the origin node; receiving, by the origin DMA engine, a remote get message containing a data descriptor for the message and a completion notification descriptor, the completion notification descriptor specifying a local direct put transfer operation for transferring data locally on the origin node; inserting, by the origin DMA engine in an injection FIFO buffer, the data descriptor followed by the completion notification descriptor; transferring, by the origin DMA engine to the target node, the message in dependence upon the data descriptor; and notifying, by the origin DMA engine, the application that transfer of the message is complete in dependence upon the completion notification descriptor.

A real time dynamic data acquisition and processing system for velocity, density, and total temperature fluctuation measurements

NASA Technical Reports Server (NTRS)

Clukey, Steven J.

1991-01-01

The real time Dynamic Data Acquisition and Processing System (DDAPS) is described which provides the capability for the simultaneous measurement of velocity, density, and total temperature fluctuations. The system of hardware and software is described in context of the wind tunnel environment. The DDAPS replaces both a recording mechanism and a separate data processing system. DDAPS receives input from hot wire anemometers. Amplifiers and filters condition the signals with computer controlled modules. The analog signals are simultaneously digitized and digitally recorded on disk. Automatic acquisition collects necessary calibration and environment data. Hot wire sensitivities are generated and applied to the hot wire data to compute fluctuations. The presentation of the raw and processed data is accomplished on demand. The interface to DDAPS is described along with the internal mechanisms of DDAPS. A summary of operations relevant to the use of the DDAPS is also provided.

Distributed Synchronization Technique for OFDMA-Based Wireless Mesh Networks Using a Bio-Inspired Algorithm

PubMed Central

Kim, Mi Jeong; Maeng, Sung Joon; Cho, Yong Soo

2015-01-01

In this paper, a distributed synchronization technique based on a bio-inspired algorithm is proposed for an orthogonal frequency division multiple access (OFDMA)-based wireless mesh network (WMN) with a time difference of arrival. The proposed time- and frequency-synchronization technique uses only the signals received from the neighbor nodes, by considering the effect of the propagation delay between the nodes. It achieves a fast synchronization with a relatively low computational complexity because it is operated in a distributed manner, not requiring any feedback channel for the compensation of the propagation delays. In addition, a self-organization scheme that can be effectively used to construct 1-hop neighbor nodes is proposed for an OFDMA-based WMN with a large number of nodes. The performance of the proposed technique is evaluated with regard to the convergence property and synchronization success probability using a computer simulation. PMID:26225974

Distributed Synchronization Technique for OFDMA-Based Wireless Mesh Networks Using a Bio-Inspired Algorithm.

PubMed

Kim, Mi Jeong; Maeng, Sung Joon; Cho, Yong Soo

2015-07-28

In this paper, a distributed synchronization technique based on a bio-inspired algorithm is proposed for an orthogonal frequency division multiple access (OFDMA)-based wireless mesh network (WMN) with a time difference of arrival. The proposed time- and frequency-synchronization technique uses only the signals received from the neighbor nodes, by considering the effect of the propagation delay between the nodes. It achieves a fast synchronization with a relatively low computational complexity because it is operated in a distributed manner, not requiring any feedback channel for the compensation of the propagation delays. In addition, a self-organization scheme that can be effectively used to construct 1-hop neighbor nodes is proposed for an OFDMA-based WMN with a large number of nodes. The performance of the proposed technique is evaluated with regard to the convergence property and synchronization success probability using a computer simulation.

Collecting data from a sensor network in a single-board computer

NASA Astrophysics Data System (ADS)

Casciati, F.; Casciati, S.; Chen, Z.-C.; Faravelli, L.; Vece, M.

2015-07-01

The EU-FP7 project SPARTACUS, currently in progress, sees the international cooperation of several partners toward the design and implementation of a satellite based asset tracking for supporting emergency management in crisis operations. Due to the emergency environment, one has to rely on a low power consumption wireless communication. Therefore, the communication hardware and software must be designed to match requirements which can only be foreseen at the level of more or less likely scenarios. The latter aspect suggests a deep use of a simulator (instead of a real network of sensors) to cover extreme situations. The former power consumption remark suggests the use of a minimal computer (Raspberry Pi) as data collector. In this paper, the results of a broad simulation campaign are reported in order to investigate the accuracy of the received data and the global power consumption for each of the considered scenarios.

Signaling completion of a message transfer from an origin compute node to a target compute node

DOEpatents

Blocksome, Michael A [Rochester, MN

2011-02-15

Signaling completion of a message transfer from an origin node to a target node includes: sending, by an origin DMA engine, an RTS message, the RTS message specifying an application message for transfer to the target node from the origin node; receiving, by the origin DMA engine, a remote get message containing a data descriptor for the message and a completion notification descriptor, the completion notification descriptor specifying a local memory FIFO data transfer operation for transferring data locally on the origin node; inserting, by the origin DMA engine in an injection FIFO buffer, the data descriptor followed by the completion notification descriptor; transferring, by the origin DMA engine to the target node, the message in dependence upon the data descriptor; and notifying, by the origin DMA engine, the application that transfer of the message is complete in dependence upon the completion notification descriptor.

Support Vector Machines Model of Computed Tomography for Assessing Lymph Node Metastasis in Esophageal Cancer with Neoadjuvant Chemotherapy.

PubMed

Wang, Zhi-Long; Zhou, Zhi-Guo; Chen, Ying; Li, Xiao-Ting; Sun, Ying-Shi

The aim of this study was to diagnose lymph node metastasis of esophageal cancer by support vector machines model based on computed tomography. A total of 131 esophageal cancer patients with preoperative chemotherapy and radical surgery were included. Various indicators (tumor thickness, tumor length, tumor CT value, total number of lymph nodes, and long axis and short axis sizes of largest lymph node) on CT images before and after neoadjuvant chemotherapy were recorded. A support vector machines model based on these CT indicators was built to predict lymph node metastasis. Support vector machines model diagnosed lymph node metastasis better than preoperative short axis size of largest lymph node on CT. The area under the receiver operating characteristic curves were 0.887 and 0.705, respectively. The support vector machine model of CT images can help diagnose lymph node metastasis in esophageal cancer with preoperative chemotherapy.

Development of the Centralized Storm Information System (CSIS) for use in severe weather prediction

NASA Technical Reports Server (NTRS)

Mosher, F. R.

1984-01-01

The centralized storm information system is now capable of ingesting and remapping radar scope presentations on a satellite projection. This can be color enhanced and superposed on other data types. Presentations from more than one radar can be composited on a single image. As with most other data sources, a simple macro establishes the loops and scheduling of the radar ingestions as well as the autodialing. There are approximately 60 NWS network 10 cm radars that can be interrogated. NSSFC forecasters have found this data source to be extremely helpful in severe weather situations. The capability to access lightning frequency data stored in a National Weather Service computer was added. Plans call for an interface with the National Meteorological Center to receive and display prognostic fields from operational computer forecast models. Programs are to be developed to plot and display locations of reported severe local storm events.

Influence of daylight and noise current on cloud and aerosol observations by spaceborne elastic scattering lidar.

PubMed

Nakajima, T Y; Imai, T; Uchino, O; Nagai, T

1999-08-20

The influence of daylight and noise current on cloud and aerosol observations by realistic spaceborne lidar was examined by computer simulations. The reflected solar radiations, which contaminate the daytime return signals of lidar operations, were strictly and explicitly estimated by accurate radiative transfer calculations. It was found that the model multilayer cirrus clouds and the boundary layer aerosols could be observed during the daytime and the nighttime with only a few laser shots. However, high background noise and noise current make it difficult to observe volcanic aerosols in middle and upper atmospheric layers. Optimal combinations of the laser power and receiver field of view are proposed to compensate for the negative influence that is due to these noises. For the computer simulations, we used a realistic set of lidar parameters similar to the Experimental Lidar in-Space Equipment of the National Space Development Agency of Japan.

Configuring compute nodes of a parallel computer in an operational group into a plurality of independent non-overlapping collective networks

DOEpatents

Archer, Charles J.; Inglett, Todd A.; Ratterman, Joseph D.; Smith, Brian E.

2010-03-02

Methods, apparatus, and products are disclosed for configuring compute nodes of a parallel computer in an operational group into a plurality of independent non-overlapping collective networks, the compute nodes in the operational group connected together for data communications through a global combining network, that include: partitioning the compute nodes in the operational group into a plurality of non-overlapping subgroups; designating one compute node from each of the non-overlapping subgroups as a master node; and assigning, to the compute nodes in each of the non-overlapping subgroups, class routing instructions that organize the compute nodes in that non-overlapping subgroup as a collective network such that the master node is a physical root.

Activities at the JSC Payload Operations Control Center During Spacelab Mission

NASA Technical Reports Server (NTRS)

1984-01-01

During a Spacelab flight, the hub of activity was the Payload Operations Control Center (POCC) at the Johnson Space Flight Center (JSC) in Houston, Texas. The POCC became home to the management and science teams who worked around the clock to guide and support the mission. All Spacelab principal investigators and their teams of scientists and engineers set up work areas in the POCC. Through the use of computers, they could send commands to their instruments and receive and analyze experiment data. Instantaneous video and audio communications made it possible for scientists on the ground to follow the progress of their research almost as if they were in space with the crew. This real-time interaction between investigators on the ground and the crew in space was probably the most exciting of Spacelab's many capabilities. As principal investigators talked to the payload specialists during the mission, they consulted on experiment operations, made decisions, and shared in the thrill of gaining new knowledge. In December 1990, a newly-established POCC at the Marshall Space Flight Center (MSFC) opened its door for the operations of the Spacelab payloads and experiments, while JSC monitored the Shuttle flight operations. MSFC had managing responsibilities for the Spacelab missions.

Deep Space Network (DSN), Network Operations Control Center (NOCC) computer-human interfaces

NASA Technical Reports Server (NTRS)

Ellman, Alvin; Carlton, Magdi

1993-01-01

The Network Operations Control Center (NOCC) of the DSN is responsible for scheduling the resources of DSN, and monitoring all multi-mission spacecraft tracking activities in real-time. Operations performs this job with computer systems at JPL connected to over 100 computers at Goldstone, Australia and Spain. The old computer system became obsolete, and the first version of the new system was installed in 1991. Significant improvements for the computer-human interfaces became the dominant theme for the replacement project. Major issues required innovating problem solving. Among these issues were: How to present several thousand data elements on displays without overloading the operator? What is the best graphical representation of DSN end-to-end data flow? How to operate the system without memorizing mnemonics of hundreds of operator directives? Which computing environment will meet the competing performance requirements? This paper presents the technical challenges, engineering solutions, and results of the NOCC computer-human interface design.

TRAO Multibeam Receiver System and Key Science Programs

NASA Astrophysics Data System (ADS)

Lee, Youngung

2017-06-01

Taeduk Radio Astronomy Observatory (TRAO) is now equipped with a main controling computer with VxWorks operating system, a new receiver system, and a new backend system. The new receiver system(TRAO-SEQUOIA) is equipped with high-performing 16-pixel MMIC pre-amplifiers in a 4x4 array, operating within 85~115 GHz frequency range. The system temperature ranges from 150 K (86~110 GHz) to 450 K (115 GHz). The 2nd IF modules with the narrow band and the 8 channels with 4 FFT spectrometers allow to observe 2 frequencies simultaneously within the 85~100 or 100~115 GHz bands for all 16 pixels of the receiver. Radome replacement was completed successfully as of February 2017. In addition, a new servo system will be installed in 2017 summer. We provide OTF (On-The-Fly) as a main observing mode, and position switching mode is available as well. The backend system (FFT spectrometer) provides the 4096x2 channels with fine velocity resolution of about 0.05 km/sec (15 kHz) per channel, and their full spectra bandwidth is 60 MHz. Beam efficiency of the TRAO was measured to be about 46% - 54% (with less than 2% error) between 86 and 115 GHz bands and pointing errors of the 14m telescope were found be 4.4 arcsec in AZ direction and 6 arcsec in EL direction. Generally, we allocate 18 hours of telescope time a day from January to the middle of May, and from October to December. Three Key Science Programs had been selected in 2015 fall and they are supposed to have higher priority for telescope time.

Computer Learning Through Piaget's Eyes.

ERIC Educational Resources Information Center

Huber, Leonard N.

1985-01-01

Discusses Piaget's pre-operational, concrete operational, and formal operational stages and shows how this information sheds light on how children approach computers and computing, particularly with the LOGO programming language. (JN)

Broadcasting a message in a parallel computer

DOEpatents

Berg, Jeremy E [Rochester, MN; Faraj, Ahmad A [Rochester, MN

2011-08-02

Methods, systems, and products are disclosed for broadcasting a message in a parallel computer. The parallel computer includes a plurality of compute nodes connected together using a data communications network. The data communications network optimized for point to point data communications and is characterized by at least two dimensions. The compute nodes are organized into at least one operational group of compute nodes for collective parallel operations of the parallel computer. One compute node of the operational group assigned to be a logical root. Broadcasting a message in a parallel computer includes: establishing a Hamiltonian path along all of the compute nodes in at least one plane of the data communications network and in the operational group; and broadcasting, by the logical root to the remaining compute nodes, the logical root's message along the established Hamiltonian path.

29 CFR 1917.155 - Air receivers.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 29 Labor 7 2012-07-01 2012-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.155 Air receivers. (a) Application. This section applies to compressed air receivers and equipment used for operations such as cleaning...

29 CFR 1917.155 - Air receivers.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 29 Labor 7 2014-07-01 2014-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.155 Air receivers. (a) Application. This section applies to compressed air receivers and equipment used for operations such as cleaning...

29 CFR 1917.155 - Air receivers.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 29 Labor 7 2013-07-01 2013-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.155 Air receivers. (a) Application. This section applies to compressed air receivers and equipment used for operations such as cleaning...

29 CFR 1917.155 - Air receivers.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 29 Labor 7 2011-07-01 2011-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.155 Air receivers. (a) Application. This section applies to compressed air receivers and equipment used for operations such as cleaning...

29 CFR 1917.155 - Air receivers.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 29 Labor 7 2010-07-01 2010-07-01 false Air receivers. 1917.155 Section 1917.155 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.155 Air receivers. (a) Application. This section applies to compressed air receivers and equipment used for operations such as cleaning...

Router Agent Technology for Policy-Based Network Management

NASA Technical Reports Server (NTRS)

Chow, Edward T.; Sudhir, Gurusham; Chang, Hsin-Ping; James, Mark; Liu, Yih-Chiao J.; Chiang, Winston

2011-01-01

This innovation can be run as a standalone network application on any computer in a networked environment. This design can be configured to control one or more routers (one instance per router), and can also be configured to listen to a policy server over the network to receive new policies based on the policy- based network management technology. The Router Agent Technology transforms the received policies into suitable Access Control List syntax for the routers it is configured to control. It commits the newly generated access control lists to the routers and provides feedback regarding any errors that were faced. The innovation also automatically generates a time-stamped log file regarding all updates to the router it is configured to control. This technology, once installed on a local network computer and started, is autonomous because it has the capability to keep listening to new policies from the policy server, transforming those policies to router-compliant access lists, and committing those access lists to a specified interface on the specified router on the network with any error feedback regarding commitment process. The stand-alone application is named RouterAgent and is currently realized as a fully functional (version 1) implementation for the Windows operating system and for CISCO routers.

KSC-99pp1227

NASA Image and Video Library

1999-10-06

Children at Audubon Elementary School, Merritt Island, Fla., eagerly unwrap computer equipment donated by Kennedy Space Center. Audubon is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. KSC employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated

Predictions of GPS X-Set Performance during the Places Experiment

DTIC Science & Technology

1979-07-01

previously existing GPS X-set receiver simulation was modified to include the received signal spectrum and the receiver code correlation operation... CORRELATION OPERATION The X-set receiver simulation documented in Reference 3-1 is a direct sampled -data digital implementation of the GPS X-set...ul(t) -sin w2t From Carrier and Code Loops (wit +0 1 (t)) Figure 3-6. Simplified block diagram of code correlator operation and I-Q sampling . 6 I

Contributed Review: Source-localization algorithms and applications using time of arrival and time difference of arrival measurements

NASA Astrophysics Data System (ADS)

Li, Xinya; Deng, Zhiqun Daniel; Rauchenstein, Lynn T.; Carlson, Thomas J.

2016-04-01

Locating the position of fixed or mobile sources (i.e., transmitters) based on measurements obtained from sensors (i.e., receivers) is an important research area that is attracting much interest. In this paper, we review several representative localization algorithms that use time of arrivals (TOAs) and time difference of arrivals (TDOAs) to achieve high signal source position estimation accuracy when a transmitter is in the line-of-sight of a receiver. Circular (TOA) and hyperbolic (TDOA) position estimation approaches both use nonlinear equations that relate the known locations of receivers and unknown locations of transmitters. Estimation of the location of transmitters using the standard nonlinear equations may not be very accurate because of receiver location errors, receiver measurement errors, and computational efficiency challenges that result in high computational burdens. Least squares and maximum likelihood based algorithms have become the most popular computational approaches to transmitter location estimation. In this paper, we summarize the computational characteristics and position estimation accuracies of various positioning algorithms. By improving methods for estimating the time-of-arrival of transmissions at receivers and transmitter location estimation algorithms, transmitter location estimation may be applied across a range of applications and technologies such as radar, sonar, the Global Positioning System, wireless sensor networks, underwater animal tracking, mobile communications, and multimedia.

Methods and compositions for protection of cells and tissues from computed tomography radiation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grdina, David J.

Described are methods for preventing or inhibiting genomic instability and in cells affected by diagnostic radiology procedures employing ionizing radiation. Embodiments include methods of preventing or inhibiting genomic instability and in cells affected by computed tomography (CT) radiation. Subjects receiving ionizing radiation may be those persons suspected of having cancer, or cancer patients having received or currently receiving cancer therapy, and or those patients having received previous ionizing radiation, including those who are approaching or have exceeded the recommended total radiation dose for a person.

Performance prediction evaluation of ceramic materials in point-focusing solar receivers

NASA Technical Reports Server (NTRS)

Ewing, J.; Zwissler, J.

1979-01-01

A performance prediction was adapted to evaluate the use of ceramic materials in solar receivers for point focusing distributed applications. System requirements were determined including the receiver operating environment and system operating parameters for various engine types. Preliminary receiver designs were evolved from these system requirements. Specific receiver designs were then evaluated to determine material functional requirements.

Fermilab Recycler Ring BPM Upgrade Based on Digital Receiver Technology

NASA Astrophysics Data System (ADS)

Webber, R.; Crisp, J.; Prieto, P.; Voy, D.; Briegel, C.; McClure, C.; West, R.; Pordes, S.; Mengel, M.

2004-11-01

Electronics for the 237 BPMs in the Fermilab Recycler Ring have been upgraded from a log-amplifier based system to a commercially produced digitizer-digital down converter based system. The hardware consists of a pre-amplifier connected to a split-plate BPM, an analog differential receiver-filter module and an 8-channel 80-MHz digital down converter VME board. The system produces position and intensity with a dynamic range of 30 dB and a resolution of ±10 microns. The position measurements are made on 2.5-MHz bunched beam and barrier buckets of the un-bunched beam. The digital receiver system operates in one of six different signal processing modes that include 2.5-MHz average, 2.5-MHz bunch-by-bunch, 2.5-MHz narrow band, unbunched average, un-bunched head/tail and 89-kHz narrow band. Receiver data is acquired on any of up to sixteen clock events related to Recycler beam transfers and other machine activities. Data from the digital receiver board are transferred to the front-end CPU for position and intensity computation on an on-demand basis through the VME bus. Data buffers are maintained for each of the acquisition events and support flash, closed orbit and turn-by-turn measurements. A calibration system provides evaluation of the BPM signal path and application programs.

Link failure detection in a parallel computer

DOEpatents

Archer, Charles J.; Blocksome, Michael A.; Megerian, Mark G.; Smith, Brian E.

2010-11-09

Methods, apparatus, and products are disclosed for link failure detection in a parallel computer including compute nodes connected in a rectangular mesh network, each pair of adjacent compute nodes in the rectangular mesh network connected together using a pair of links, that includes: assigning each compute node to either a first group or a second group such that adjacent compute nodes in the rectangular mesh network are assigned to different groups; sending, by each of the compute nodes assigned to the first group, a first test message to each adjacent compute node assigned to the second group; determining, by each of the compute nodes assigned to the second group, whether the first test message was received from each adjacent compute node assigned to the first group; and notifying a user, by each of the compute nodes assigned to the second group, whether the first test message was received.

The effect of feature selection methods on computer-aided detection of masses in mammograms

NASA Astrophysics Data System (ADS)

Hupse, Rianne; Karssemeijer, Nico

2010-05-01

In computer-aided diagnosis (CAD) research, feature selection methods are often used to improve generalization performance of classifiers and shorten computation times. In an application that detects malignant masses in mammograms, we investigated the effect of using a selection criterion that is similar to the final performance measure we are optimizing, namely the mean sensitivity of the system in a predefined range of the free-response receiver operating characteristics (FROC). To obtain the generalization performance of the selected feature subsets, a cross validation procedure was performed on a dataset containing 351 abnormal and 7879 normal regions, each region providing a set of 71 mass features. The same number of noise features, not containing any information, were added to investigate the ability of the feature selection algorithms to distinguish between useful and non-useful features. It was found that significantly higher performances were obtained using feature sets selected by the general test statistic Wilks' lambda than using feature sets selected by the more specific FROC measure. Feature selection leads to better performance when compared to a system in which all features were used.

Computer-Aided Diagnosis for Breast Ultrasound Using Computerized BI-RADS Features and Machine Learning Methods.

PubMed

Shan, Juan; Alam, S Kaisar; Garra, Brian; Zhang, Yingtao; Ahmed, Tahira

2016-04-01

This work identifies effective computable features from the Breast Imaging Reporting and Data System (BI-RADS), to develop a computer-aided diagnosis (CAD) system for breast ultrasound. Computerized features corresponding to ultrasound BI-RADs categories were designed and tested using a database of 283 pathology-proven benign and malignant lesions. Features were selected based on classification performance using a "bottom-up" approach for different machine learning methods, including decision tree, artificial neural network, random forest and support vector machine. Using 10-fold cross-validation on the database of 283 cases, the highest area under the receiver operating characteristic (ROC) curve (AUC) was 0.84 from a support vector machine with 77.7% overall accuracy; the highest overall accuracy, 78.5%, was from a random forest with the AUC 0.83. Lesion margin and orientation were optimum features common to all of the different machine learning methods. These features can be used in CAD systems to help distinguish benign from worrisome lesions. Copyright © 2016 World Federation for Ultrasound in Medicine & Biology. All rights reserved.

256 Slice Multi-detector Computed Tomography Thoracic Aorta Computed Tomography Angiography: Improved Luminal Opacification Using a Patient-Specific Contrast Protocol and Caudocranial Scan Acquisition.

PubMed

Saade, Charbel; El-Merhi, Fadi; El-Achkar, Bassam; Kerek, Racha; Vogl, Thomas J; Maroun, Gilbert Georges; Jamjoom, Lamia; Al-Mohiy, Hussain; Naffaa, Lena

Caudocranial scan direction and contrast injection timing based on measured patient vessel dynamics can significantly improve arterial and aneurysmal opacification and reduce both contrast and radiation dose in the assessment of thoracic aortic aneurysms (TAA) using helical thoracic computed tomography angiography (CTA). To investigate opacification of the thoracic aorta and TAA using a caudocranial scan direction and a patient-specific contrast protocol. Thoracic aortic CTA was performed in 160 consecutive patients with suspected TAA using a 256-slice computed tomography scanner and a dual barrel contrast injector. Patients were subjected in equal numbers to one of two contrast protocols. Patient age and sex were equally distributed across both groups. Protocol A, the department's standard protocol, consisted of a craniocaudal scan direction with 100 mL of contrast, intravenously injected at a flow rate of 4.5 mL/s. Protocol B involved a caudocranial scan direction and a novel contrast formula based on patient cardiovascular dynamics, followed by 100 mL of saline at 4.5 mL/s. Each scan acquisition comprised of 120 kVp, 200 mA with modulation, temporal resolution 0.27 seconds, and pitch 0.889:1. The dose length product was measured between each protocol and data generated were compared using Mann-Whitney U nonparametric statistics. Receiver operating characteristic analysis, visual grading characteristic (VGC), and κ analyses were performed. Mean opacification in the thoracic aorta and aneurysm measured was 24 % and 55%, respectively. The mean contrast volume was significantly lower in protocol B (73 ± 10 mL) compared with A (100 ± 1 mL) (P<0.001). The contrast-to-noise ratio demonstrated significant differences between the protocols (protocol A, 18.2 ± 12.9; protocol B, 29.7 ± 0.61; P < 0.003). Mean effective dose in protocol B (2.6 ± 0.4 mSv) was reduced by 19% compared with A (3.2 ± 0.8 mSv) (P < 0.004). Aneurysmal detectability demonstrated significant increases by receiver operating characteristic and visual grading characteristic analysis for protocol B compared with A (P < 0.02), and reader agreement increased from poor to excellent. Significant increase in the visualization of TAAs following a caudocranial scan direction during helical thoracic CTA can be achieved using low-contrast volume based on patient-specific contrast formula.

Computer-Based Radiographic Quantification of Joint Space Narrowing Progression Using Sequential Hand Radiographs: Validation Study in Rheumatoid Arthritis Patients from Multiple Institutions.

PubMed

Ichikawa, Shota; Kamishima, Tamotsu; Sutherland, Kenneth; Fukae, Jun; Katayama, Kou; Aoki, Yuko; Okubo, Takanobu; Okino, Taichi; Kaneda, Takahiko; Takagi, Satoshi; Tanimura, Kazuhide

2017-10-01

We have developed a refined computer-based method to detect joint space narrowing (JSN) progression with the joint space narrowing progression index (JSNPI) by superimposing sequential hand radiographs. The purpose of this study is to assess the validity of a computer-based method using images obtained from multiple institutions in rheumatoid arthritis (RA) patients. Sequential hand radiographs of 42 patients (37 females and 5 males) with RA from two institutions were analyzed by a computer-based method and visual scoring systems as a standard of reference. The JSNPI above the smallest detectable difference (SDD) defined JSN progression on the joint level. The sensitivity and specificity of the computer-based method for JSN progression was calculated using the SDD and a receiver operating characteristic (ROC) curve. Out of 314 metacarpophalangeal joints, 34 joints progressed based on the SDD, while 11 joints widened. Twenty-one joints progressed in the computer-based method, 11 joints in the scoring systems, and 13 joints in both methods. Based on the SDD, we found lower sensitivity and higher specificity with 54.2 and 92.8%, respectively. At the most discriminant cutoff point according to the ROC curve, the sensitivity and specificity was 70.8 and 81.7%, respectively. The proposed computer-based method provides quantitative measurement of JSN progression using sequential hand radiographs and may be a useful tool in follow-up assessment of joint damage in RA patients.

Implementation of NASTRAN on the IBM/370 CMS operating system

NASA Technical Reports Server (NTRS)

Britten, S. S.; Schumacker, B.

1980-01-01

The NASA Structural Analysis (NASTRAN) computer program is operational on the IBM 360/370 series computers. While execution of NASTRAN has been described and implemented under the virtual storage operating systems of the IBM 370 models, the IBM 370/168 computer can also operate in a time-sharing mode under the virtual machine operating system using the Conversational Monitor System (CMS) subset. The changes required to make NASTRAN operational under the CMS operating system are described.

FAA Air Traffic Control Operations Concepts. Volume 2. ACF/ACCC (Area Control Facility/Area Control Computer Complex) Terminal and En Route Controllers. Change 1

DTIC Science & Technology

1988-07-29

VOLff2) 6 July 19837 A-74 A1.5.6 MONITORING NON-CONTROLLED OBJECTS AIM, 7 OIHERS REPORT AIRSPACEJ FIRST 10 DETECT INTRUSION IradR’SIoN BY NON-CON’TROLLED 1...1988 Volume II: ACF/ACCC Terminal and En Route Controllers (ClIG 1) 6 . Porliming Organization Code 7 . Author(s) 8. Performing Organization Report No...MANEUVER SYSTEM GENERATES ABSORPT ION PREVIOUSLY PREPARED RECEIVED MANEUVER FOR A FLIGHT CLEAPANCEI D0T/FAA/AP-47-01 (VOLt2) 6 July 1987 A- 7 A,1.O

Tse computers. [Chinese pictograph character binary image processor design for high speed applications

NASA Technical Reports Server (NTRS)

Strong, J. P., III

1973-01-01

Tse computers have the potential of operating four or five orders of magnitude faster than present digital computers. The computers of the new design use binary images as their basic computational entity. The word 'tse' is the transliteration of the Chinese word for 'pictograph character.' Tse computers are large collections of devices that perform logical operations on binary images. The operations on binary images are to be performed over the entire image simultaneously.

Comparative study on fractal analysis of interferometry images with application to tear film surface quality assessment.

PubMed

Szyperski, Piotr D

2018-06-01

The purpose of this research was to evaluate the applicability of the fractal dimension (FD) estimators to assess lateral shearing interferometric (LSI) measurements of tear film surface quality. Retrospective recordings of tear film measured with LSI were used: 69 from healthy subjects and 41 from patients diagnosed with dry eye syndrome. Five surface quality descriptors were considered, four based on FD and a previously reported descriptor operating in a spatial frequency domain (M 2 ), presenting temporal kinetics of post-blink tear film. A set of 12 regression parameters has been extracted and analyzed for classification purposes. The classifiers are assessed in terms of receiver operating characteristics and areas under their curves (AUC). Also, the computational loads are estimated. The maximum AUC of 82.4% was achieved for M 2 , closely followed by the binary box-counting (BBC) FD estimator with AUC=78.6%. For all descriptors, statistically significant differences between the subject groups were found (p<0.05). The BBC FD estimator was characterized with the highest empirical computational efficiency that was about 30% faster than that of M 2 , while that based on the differential box-counting exhibited the lowest efficiency (4.5 times slower than the best one). Concluding, FD estimators can be utilized for quantitative assessment of tear film kinetics. They provide a viable alternative to previously used spectral counter parameters, and at the same time allow higher computational efficiency.

A College That Relied on NeXT Computers Plans To Switch to Apple.

ERIC Educational Resources Information Center

Wilson, David L.

1997-01-01

Allegheny College (Pennsylvania), which uses NeXT computers, was dismayed when the technically superior operating system was orphaned but are now delighted that the company has been bought by Apple Computer and will make the operating system standard on Apple computers. The object-oriented operating system allows relatively unsophisticated users…

Radiant energy receiver having improved coolant flow control means

DOEpatents

Hinterberger, H.

1980-10-29

An improved coolant flow control for use in radiant energy receivers of the type having parallel flow paths is disclosed. A coolant performs as a temperature dependent valve means, increasing flow in the warmer flow paths of the receiver, and impeding flow in the cooler paths of the receiver. The coolant has a negative temperature coefficient of viscosity which is high enough such that only an insignificant flow through the receiver is experienced at the minimum operating temperature of the receiver, and such that a maximum flow is experienced at the maximum operating temperature of the receiver. The valving is accomplished by changes in viscosity of the coolant in response to the coolant being heated and cooled. No remotely operated valves, comparators or the like are needed.

Crustal structure across the lateral edge of the Southern Tyrrhenian slab

NASA Astrophysics Data System (ADS)

Pio Lucente, Francesco; Piana Agostinetti, Nicola; Di Bona, Massimo; Govoni, Aladino; Bianchi, Irene

2015-04-01

In the southeastern corner of the Tyrrhenian basin, in the central Mediterranean Sea, a tight alignment of earthquakes along a well-defined Benioff zone reveals the presence of one of the narrowest active trenches worldwide, where one of the last fragments of the former Tethys ocean is consumed. Seismic tomography furnishes snapshot images of the present-day position and shape of this slab. Through receiver function analysis we investigate the layered structures overlying the slab. We compute receiver functions from the P-coda of teleseismic events at 13 temporary station deployed during the "Messina 1908-2008" research project (Margheriti, 2008), and operating for an average period of 15 months each. The crustal and uppermost mantle structure has been investigated using a trans-dimensional McMC algorithm developed by Piana Agostinetti and Malinverno (2010), obtaining a 1D S-wave velocity profile for each station. At three of the stations, operating for a longer period of time, the number and the azimuthal distribution of teleseisms allowed us to stack the RF data-set with back azimuth and to compute the harmonic expansion. The analysis of the back-azimuthal harmonics gave us insight on the presence of dipping interfaces and anisotropic layers at depth. The strike and the dip of interfaces and the anisotropic parameters have been quantified using the Neighbourhood Algorithm (Sambridge, 1999). Preliminary results highlight: (1) a neat differentiation of the isotropic S-wave velocity structure passing through the slab edge, from the tip of the Calabrian arc to the Peloritani Range, and (2) the presence of crustal complexities, such as dipping interfaces and anisotropic layers, both in the upper and lower crust. Margheriti, L. (2008), Understanding Crust Dynamics and Subduction in Southern Italy, Eos Trans. AGU, 89(25), 225-226, doi:10.1029/2008EO250002. Piana Agostinetti, N. and A. Malinverno (2010) Receiver Function inversion by trans-dimensional Monte Carlo sampling, Geophys. J. Int., 181(2) 858-872, doi: 10.1111/j.1365-246X.2010.04530.x Sambridge, M. (1999), Geophysical inversion with a neighbourhood algorithm-I. Searching a parameter space, Geophys. J. Int., 138, 479-494, doi:10.1046/j.1365-246X.1999.00876.x.

Mars Robotics in the Elementary School

NASA Astrophysics Data System (ADS)

Bonett, D.

2003-05-01

Kenneth E. Little Elementary is a public school grades Pre-K to 5th in Bacliff, Texas. It has an ethnically diverse population of one-thousand boys and girls. It is a Title 1 school with eighty-six percent of the students receiving free or reduced meals. K.E. Little has a large at-risk population with a thirty-three percent transition rate. The Young Astronauts @ K.E. Little is an on-going afterschool space science program in it's third year of operation. Thirty students,fourth and fifth grade, were involved in our spring robotics program. Each co-operative group was assigned a LEGO robotics kit to inventory,organize, and familiarize themselves with. Each team made decisions, by consensus, concerning the robots design and capabilities. Students used the Dell Computer Lab on campus to program their robots. Although time did not permit the construction of a simulated Martian landscape, future Young Astronauts will continue this project in January 2004.

The use of a laser ceilometer for sky condition determination

NASA Astrophysics Data System (ADS)

Nadolski, Vickie L.; Bradley, James T.

The use of a laser ceilometer for determining sky condition is presented, with emphasis on the operation of the ceilometer, the sky-condition-reporting algorithm, and how the laser ceilometer and the sky-condition algorithm are used to give a report suitable for aircraft operations and meteorological application. The sampling and processing features of the Vaisala ceilometer produced a detailed and accurate cloud base 'signature' by taking 254 measurement samples of the energy scattered back from a single laser pulse as the pulse traveled from the surface to 12,000 ft. The transmit time from the projection of the laser pulse to its backscattering from a cloud element and subsequent return to a collocated receiver is measured and a cloud height element computed. Attention is given to the development of a vertical visibility concept and of a vertical-visibility algorithm, as well as the strengths and limitations of the sky condition report.

KSC-99pp1225

NASA Image and Video Library

1999-10-06

Children at Coquina Elementary School, Titusville, Fla., excitedly tear into the wrapped computer equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. KSC employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated

KSC-99pp1224

NASA Image and Video Library

1999-10-06

Children at Coquina Elementary School, Titusville, Fla., eagerly tear into the wrapped computer equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. KSC employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated

KSC-99pp1222

NASA Image and Video Library

1999-10-06

Children at Coquina Elementary School, Titusville, Fla., look with curiosity at the wrapped computer equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. KSC employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated

KSC-99pp1223

NASA Image and Video Library

1999-10-06

Children at Coquina Elementary School, Titusville, Fla., "practice" using a computer keyboard, part of equipment donated by Kennedy Space Center. Coquina is one of 13 Brevard County schools receiving 81 excess contractor computers thanks to an innovative educational outreach project spearheaded by the Nasa k-12 Education Services Office at ksc. The Astronaut Memorial Foundation, a strategic partner in the effort, and several schools in rural Florida and Georgia also received refurbished computers as part of the year-long project. KSC employees put in about 3,300 volunteer hours to transform old, excess computers into upgraded, usable units. A total of $90,000 in upgraded computer equipment is being donated

A Functional Analytic Approach to Computer-Interactive Mathematics

ERIC Educational Resources Information Center

Ninness, Chris; Rumph, Robin; McCuller, Glen; Harrison, Carol; Ford, Angela M.; Ninness, Sharon K.

2005-01-01

Following a pretest, 11 participants who were naive with regard to various algebraic and trigonometric transformations received an introductory lecture regarding the fundamentals of the rectangular coordinate system. Following the lecture, they took part in a computer-interactive matching-to-sample procedure in which they received training on…

Observer training for computer-aided detection of pulmonary nodules in chest radiography.

PubMed

De Boo, Diederick W; van Hoorn, François; van Schuppen, Joost; Schijf, Laura; Scheerder, Maeke J; Freling, Nicole J; Mets, Onno; Weber, Michael; Schaefer-Prokop, Cornelia M

2012-08-01

To assess whether short-term feedback helps readers to increase their performance using computer-aided detection (CAD) for nodule detection in chest radiography. The 140 CXRs (56 with a solitary CT-proven nodules and 84 negative controls) were divided into four subsets of 35; each were read in a different order by six readers. Lesion presence, location and diagnostic confidence were scored without and with CAD (IQQA-Chest, EDDA Technology) as second reader. Readers received individual feedback after each subset. Sensitivity, specificity and area under the receiver-operating characteristics curve (AUC) were calculated for readings with and without CAD with respect to change over time and impact of CAD. CAD stand-alone sensitivity was 59 % with 1.9 false-positives per image. Mean AUC slightly increased over time with and without CAD (0.78 vs. 0.84 with and 0.76 vs. 0.82 without CAD) but differences did not reach significance. The sensitivity increased (65 % vs. 70 % and 66 % vs. 70 %) and specificity decreased over time (79 % vs. 74 % and 80 % vs. 77 %) but no significant impact of CAD was found. Short-term feedback does not increase the ability of readers to differentiate true- from false-positive candidate lesions and to use CAD more effectively. • Computer-aided detection (CAD) is increasingly used as an adjunct for many radiological techniques. • Short-term feedback does not improve reader performance with CAD in chest radiography. • Differentiation between true- and false-positive CAD for low conspicious possible lesions proves difficult. • CAD can potentially increase reader performance for nodule detection in chest radiography.

A Frequency-Domain Multipath Parameter Estimation and Mitigation Method for BOC-Modulated GNSS Signals

PubMed Central

Sun, Chao; Feng, Wenquan; Du, Songlin

2018-01-01

As multipath is one of the dominating error sources for high accuracy Global Navigation Satellite System (GNSS) applications, multipath mitigation approaches are employed to minimize this hazardous error in receivers. Binary offset carrier modulation (BOC), as a modernized signal structure, is adopted to achieve significant enhancement. However, because of its multi-peak autocorrelation function, conventional multipath mitigation techniques for binary phase shift keying (BPSK) signal would not be optimal. Currently, non-parametric and parametric approaches have been studied specifically aiming at multipath mitigation for BOC signals. Non-parametric techniques, such as Code Correlation Reference Waveforms (CCRW), usually have good feasibility with simple structures, but suffer from low universal applicability for different BOC signals. Parametric approaches can thoroughly eliminate multipath error by estimating multipath parameters. The problems with this category are at the high computation complexity and vulnerability to the noise. To tackle the problem, we present a practical parametric multipath estimation method in the frequency domain for BOC signals. The received signal is transferred to the frequency domain to separate out the multipath channel transfer function for multipath parameter estimation. During this process, we take the operations of segmentation and averaging to reduce both noise effect and computational load. The performance of the proposed method is evaluated and compared with the previous work in three scenarios. Results indicate that the proposed averaging-Fast Fourier Transform (averaging-FFT) method achieves good robustness in severe multipath environments with lower computational load for both low-order and high-order BOC signals. PMID:29495589

DSN Array Simulator

NASA Technical Reports Server (NTRS)

Tikidjian, Raffi; Mackey, Ryan

2008-01-01

The DSN Array Simulator (wherein 'DSN' signifies NASA's Deep Space Network) is an updated version of software previously denoted the DSN Receive Array Technology Assessment Simulation. This software (see figure) is used for computational modeling of a proposed DSN facility comprising user-defined arrays of antennas and transmitting and receiving equipment for microwave communication with spacecraft on interplanetary missions. The simulation includes variations in spacecraft tracked and communication demand changes for up to several decades of future operation. Such modeling is performed to estimate facility performance, evaluate requirements that govern facility design, and evaluate proposed improvements in hardware and/or software. The updated version of this software affords enhanced capability for characterizing facility performance against user-defined mission sets. The software includes a Monte Carlo simulation component that enables rapid generation of key mission-set metrics (e.g., numbers of links, data rates, and date volumes), and statistical distributions thereof as functions of time. The updated version also offers expanded capability for mixed-asset network modeling--for example, for running scenarios that involve user-definable mixtures of antennas having different diameters (in contradistinction to a fixed number of antennas having the same fixed diameter). The improved version also affords greater simulation fidelity, sufficient for validation by comparison with actual DSN operations and analytically predictable performance metrics.

Influence of ECG measurement accuracy on ECG diagnostic statements.

PubMed

Zywietz, C; Celikag, D; Joseph, G

1996-01-01

Computer analysis of electrocardiograms (ECGs) provides a large amount of ECG measurement data, which may be used for diagnostic classification and storage in ECG databases. Until now, neither error limits for ECG measurements have been specified nor has their influence on diagnostic statements been systematically investigated. An analytical method is presented to estimate the influence of measurement errors on the accuracy of diagnostic ECG statements. Systematic (offset) errors will usually result in an increase of false positive or false negative statements since they cause a shift of the working point on the receiver operating characteristics curve. Measurement error dispersion broadens the distribution function of discriminative measurement parameters and, therefore, usually increases the overlap between discriminative parameters. This results in a flattening of the receiver operating characteristics curve and an increase of false positive and false negative classifications. The method developed has been applied to ECG conduction defect diagnoses by using the proposed International Electrotechnical Commission's interval measurement tolerance limits. These limits appear too large because more than 30% of false positive atrial conduction defect statements and 10-18% of false intraventricular conduction defect statements could be expected due to tolerated measurement errors. To assure long-term usability of ECG measurement databases, it is recommended that systems provide its error tolerance limits obtained on a defined test set.

Encryption for Remote Control via Internet or Intranet

NASA Technical Reports Server (NTRS)

Lineberger, Lewis

2005-01-01

A data-communication protocol has been devised to enable secure, reliable remote control of processes and equipment via a collision-based network, while using minimal bandwidth and computation. The network could be the Internet or an intranet. Control is made secure by use of both a password and a dynamic key, which is sent transparently to a remote user by the controlled computer (that is, the computer, located at the site of the equipment or process to be controlled, that exerts direct control over the process). The protocol functions in the presence of network latency, overcomes errors caused by missed dynamic keys, and defeats attempts by unauthorized remote users to gain control. The protocol is not suitable for real-time control, but is well suited for applications in which control latencies up to about 0.5 second are acceptable. The encryption scheme involves the use of both a dynamic and a private key, without any additional overhead that would degrade performance. The dynamic key is embedded in the equipment- or process-monitor data packets sent out by the controlled computer: in other words, the dynamic key is a subset of the data in each such data packet. The controlled computer maintains a history of the last 3 to 5 data packets for use in decrypting incoming control commands. In addition, the controlled computer records a private key (password) that is given to the remote computer. The encrypted incoming command is permuted by both the dynamic and private key. A person who records the command data in a given packet for hostile purposes cannot use that packet after the public key expires (typically within 3 seconds). Even a person in possession of an unauthorized copy of the command/remote-display software cannot use that software in the absence of the password. The use of a dynamic key embedded in the outgoing data makes the central-processing unit overhead very small. The use of a National Instruments DataSocket(TradeMark) (or equivalent) protocol or the User Datagram Protocol makes it possible to obtain reasonably short response times: Typical response times in event-driven control, using packets sized .300 bytes, are <0.2 second for commands issued from locations anywhere on Earth. The protocol requires that control commands represent absolute values of controlled parameters (e.g., a specified temperature), as distinguished from changes in values of controlled parameters (e.g., a specified increment of temperature). Each command is issued three or more times to ensure delivery in crowded networks. The use of absolute-value commands prevents additional (redundant) commands from causing trouble. Because a remote controlling computer receives "talkback" in the form of data packets from the controlled computer, typically within a time interval < or =1 s, the controlling computer can re-issue a command if network failure has occurred. The controlled computer, the process or equipment that it controls, and any human operator(s) at the site of the controlled equipment or process should be equipped with safety measures to prevent damage to equipment or injury to humans. These features could be a combination of software, external hardware, and intervention by the human operator(s). The protocol is not fail-safe, but by adopting these safety measures as part of the protocol, one makes the protocol a robust means of controlling remote processes and equipment by use of typical office computers via intranets and/or the Internet.

Visible scintillation photodetector device incorporating chalcopyrite semiconductor crystals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stowe, Ashley C.; Burger, Arnold

2017-04-04

A photodetector device, including: a scintillator material operable for receiving incident radiation and emitting photons in response; a photodetector material coupled to the scintillator material operable for receiving the photons emitted by the scintillator material and generating a current in response, wherein the photodetector material includes a chalcopyrite semiconductor crystal; and a circuit coupled to the photodetector material operable for characterizing the incident radiation based on the current generated by the photodetector material. Optionally, the scintillator material includes a gamma scintillator material and the incident radiation received includes gamma rays. Optionally, the photodetector material is further operable for receiving thermalmore » neutrons and generating a current in response. The circuit is further operable for characterizing the thermal neutrons based on the current generated by the photodetector material.« less

Computer Programs for Library Operations; Results of a Survey Conducted Between Fall 1971 and Spring 1972.

ERIC Educational Resources Information Center

Liberman, Eva; And Others

Many library operations involving large data banks lend themselves readily to computer operation. In setting up library computer programs, in changing or expanding programs, cost in programming and time delays could be substantially reduced if the programmers had access to library computer programs being used by other libraries, providing similar…

Method for concurrent execution of primitive operations by dynamically assigning operations based upon computational marked graph and availability of data

NASA Technical Reports Server (NTRS)

Mielke, Roland V. (Inventor); Stoughton, John W. (Inventor)

1990-01-01

Computationally complex primitive operations of an algorithm are executed concurrently in a plurality of functional units under the control of an assignment manager. The algorithm is preferably defined as a computationally marked graph contianing data status edges (paths) corresponding to each of the data flow edges. The assignment manager assigns primitive operations to the functional units and monitors completion of the primitive operations to determine data availability using the computational marked graph of the algorithm. All data accessing of the primitive operations is performed by the functional units independently of the assignment manager.

Solar tower enhanced natural draft dry cooling tower

NASA Astrophysics Data System (ADS)

Yang, Huiqiang; Xu, Yan; Acosta-Iborra, Alberto; Santana, Domingo

2017-06-01

Concentrating Solar Power (CSP) plants are located in desert areas where the Direct Normal Irradiance (DNI) value is very high. Since water resource is scarcely available, mechanical draft cooing technology is commonly used, with power consumption of mechanical fans being approximately 2% of the total power generated. Today, there is only one solar power plant (Khi Solar One in South Africa) uses a condenser installed in a Natural Draft Cooling (NDC) tower that avoids the windage loss of water occurring in wet cooling towers. Although, Khi Solar One is a cavity receiver power tower, the receivers can be hung onto the NDC tower. This paper looks at a novel integration of a NDC tower into an external molten salt receiver of a solar power plant, which is one of a largest commercial molten salt tower in China, with 100MWe power capacity. In this configuration study, the NDC tower surrounds the concrete tower of the receiver concentrically. In this way, the receiver concrete tower is the central support of the NDC tower, which consists of cable networks that are fixed to the concrete tower and suspended at a certain height over the floor. The cable networks support the shell of the NDC tower. To perform a preliminary analysis of the behavior of this novel configuration, two cases of numerical simulation in three dimensional (3D) models have been solved using the commercial Computational Fluid Dynamics (CFD) code, ANSYS Fluent 6.3. The results show that the integration of the NDC tower into an external central receiver tower is feasible. Additionally, the total heat transfer rate is not reduced but slightly increases when the molten salt receiver is in operation because of the additional natural draft induced by the high temperature of the receiver.

Digital computer operation of a nuclear reactor

DOEpatents

Colley, R.W.

1982-06-29

A method is described for the safe operation of a complex system such as a nuclear reactor using a digital computer. The computer is supplied with a data base containing a list of the safe state of the reactor and a list of operating instructions for achieving a safe state when the actual state of the reactor does not correspond to a listed safe state, the computer selects operating instructions to return the reactor to a safe state.

Digital computer operation of a nuclear reactor

DOEpatents

Colley, Robert W.

1984-01-01

A method is described for the safe operation of a complex system such as a nuclear reactor using a digital computer. The computer is supplied with a data base containing a list of the safe state of the reactor and a list of operating instructions for achieving a safe state when the actual state of the reactor does not correspond to a listed safe state, the computer selects operating instructions to return the reactor to a safe state.

RAINLINK: Retrieval algorithm for rainfall monitoring employing microwave links from a cellular communication network

NASA Astrophysics Data System (ADS)

Uijlenhoet, R.; Overeem, A.; Leijnse, H.; Rios Gaona, M. F.

2017-12-01

The basic principle of rainfall estimation using microwave links is as follows. Rainfall attenuates the electromagnetic signals transmitted from one telephone tower to another. By measuring the received power at one end of a microwave link as a function of time, the path-integrated attenuation due to rainfall can be calculated, which can be converted to average rainfall intensities over the length of a link. Microwave links from cellular communication networks have been proposed as a promising new rainfall measurement technique for one decade. They are particularly interesting for those countries where few surface rainfall observations are available. Yet to date no operational (real-time) link-based rainfall products are available. To advance the process towards operational application and upscaling of this technique, there is a need for freely available, user-friendly computer code for microwave link data processing and rainfall mapping. Such software is now available as R package "RAINLINK" on GitHub (https://github.com/overeem11/RAINLINK). It contains a working example to compute link-based 15-min rainfall maps for the entire surface area of The Netherlands for 40 hours from real microwave link data. This is a working example using actual data from an extensive network of commercial microwave links, for the first time, which will allow users to test their own algorithms and compare their results with ours. The package consists of modular functions, which facilitates running only part of the algorithm. The main processings steps are: 1) Preprocessing of link data (initial quality and consistency checks); 2) Wet-dry classification using link data; 3) Reference signal determination; 4) Removal of outliers ; 5) Correction of received signal powers; 6) Computation of mean path-averaged rainfall intensities; 7) Interpolation of rainfall intensities ; 8) Rainfall map visualisation. Some applications of RAINLINK will be shown based on microwave link data from a temperate climate (the Netherlands), and from a subtropical climate (Brazil). We hope that RAINLINK will promote the application of rainfall monitoring using microwave links in poorly gauged regions around the world. We invite researchers to contribute to RAINLINK to make the code more generally applicable to data from different networks and climates.

A Mobility Management Using Follow-Me Cloud-Cloudlet in Fog-Computing-Based RANs for Smart Cities.

PubMed

Chen, Yuh-Shyan; Tsai, Yi-Ting

2018-02-06

Mobility management for supporting the location tracking and location-based service (LBS) is an important issue of smart city by providing the means for the smooth transportation of people and goods. The mobility is useful to contribute the innovation in both public and private transportation infrastructures for smart cities. With the assistance of edge/fog computing, this paper presents a fully new mobility management using the proposed follow-me cloud-cloudlet (FMCL) approach in fog-computing-based radio access networks (Fog-RANs) for smart cities. The proposed follow-me cloud-cloudlet approach is an integration strategy of follow-me cloud (FMC) and follow-me edge (FME) (or called cloudlet). A user equipment (UE) receives the data, transmitted from original cloud, into the original edge cloud before the handover operation. After the handover operation, an UE searches for a new cloud, called as a migrated cloud, and a new edge cloud, called as a migrated edge cloud near to UE, where the remaining data is migrated from the original cloud to the migrated cloud and all the remaining data are received in the new edge cloud. Existing FMC results do not have the property of the VM migration between cloudlets for the purpose of reducing the transmission latency, and existing FME results do not keep the property of the service migration between data centers for reducing the transmission latency. Our proposed FMCL approach can simultaneously keep the VM migration between cloudlets and service migration between data centers to significantly reduce the transmission latency. The new proposed mobility management using FMCL approach aims to reduce the total transmission time if some data packets are pre-scheduled and pre-stored into the cache of cloudlet if UE is switching from the previous Fog-RAN to the serving Fog-RAN. To illustrate the performance achievement, the mathematical analysis and simulation results are examined in terms of the total transmission time, the throughput, the probability of packet loss, and the number of control messages.

A Mobility Management Using Follow-Me Cloud-Cloudlet in Fog-Computing-Based RANs for Smart Cities

PubMed Central

Tsai, Yi-Ting

2018-01-01

Mobility management for supporting the location tracking and location-based service (LBS) is an important issue of smart city by providing the means for the smooth transportation of people and goods. The mobility is useful to contribute the innovation in both public and private transportation infrastructures for smart cities. With the assistance of edge/fog computing, this paper presents a fully new mobility management using the proposed follow-me cloud-cloudlet (FMCL) approach in fog-computing-based radio access networks (Fog-RANs) for smart cities. The proposed follow-me cloud-cloudlet approach is an integration strategy of follow-me cloud (FMC) and follow-me edge (FME) (or called cloudlet). A user equipment (UE) receives the data, transmitted from original cloud, into the original edge cloud before the handover operation. After the handover operation, an UE searches for a new cloud, called as a migrated cloud, and a new edge cloud, called as a migrated edge cloud near to UE, where the remaining data is migrated from the original cloud to the migrated cloud and all the remaining data are received in the new edge cloud. Existing FMC results do not have the property of the VM migration between cloudlets for the purpose of reducing the transmission latency, and existing FME results do not keep the property of the service migration between data centers for reducing the transmission latency. Our proposed FMCL approach can simultaneously keep the VM migration between cloudlets and service migration between data centers to significantly reduce the transmission latency. The new proposed mobility management using FMCL approach aims to reduce the total transmission time if some data packets are pre-scheduled and pre-stored into the cache of cloudlet if UE is switching from the previous Fog-RAN to the serving Fog-RAN. To illustrate the performance achievement, the mathematical analysis and simulation results are examined in terms of the total transmission time, the throughput, the probability of packet loss, and the number of control messages. PMID:29415510

Exponentially Decelerated Contrast Media Injection Rate Combined With a Novel Patient-Specific Contrast Formula Reduces Contrast Volume Administration and Radiation Dose During Computed Tomography Pulmonary Angiography.

PubMed

Saade, Charbel; Mayat, Ahmad; El-Merhi, Fadi

2016-01-01

Matching contrast injection timing with vessel dynamics significantly improves vessel opacification and reduces contrast dose in the assessment of pulmonary embolism during computed tomography (CT) pulmonary angiography. The aim of this study was to investigate opacification of the pulmonary vasculature (PV) during CT pulmonary angiography using a patient-specific contrast formula (PSCF) and exponentially decelerated contrast media (EDCM) injection rate. Institutional review board approved this retrospective study. Computed tomography pulmonary angiography was performed on 200 patients with suspected pulmonary embolism using a 64-channel CT scanner. Patient demographics were equally distributed. Patients were randomly assigned to 2 equal protocol groups: protocol A used a PSCF, and protocol B involved the use of a PSCF combined with EDCM. The mean cross-sectional opacification profile of 8 central and 11 peripheral PVs were measured for each patient, and arteriovenous contrast ratio was calculated. Protocols were compared using Mann-Whitney U nonparametric statistics. Jackknife alternative free-response receiver operating characteristic analyses were used to assess diagnostic efficacy. Interobserver variations were investigated using kappa methods. A number of pulmonary arteries demonstrated increases in opacification (P < 0.02) for protocol B compared with A, whereas opacification in all veins was reduced in protocol B (P < 0.03). Subsequently, increased arteriovenous contrast ratio in protocol B compared with A was observed at all anatomic locations (P < 0.0002). An increase in jackknife alternative free-response receiver operating characteristic figure of merit (P < 0.0002) and interobserver variation was observed with protocol B compared with protocol A (κ = 0.3-0.73). Mean contrast volume was reduced in protocol B (29 [4] mL) compared with protocol A (33 [9] mL). Mean effective radiation dose in protocol B (1.2 [0.4] mSv) was reduced by 14% compared with protocol A (1.4 [0.6] mSv). Significant improvements in visualization of the PV can be achieved with a low contrast volume using an EDCM and PSCF. The reduced risk of cancer induction is highlighted.

Evaluating the risk of appendiceal perforation when using ultrasound as the initial diagnostic imaging modality in children with suspected appendicitis.

PubMed

Alerhand, Stephen; Meltzer, James; Tay, Ee Tein

2017-08-01

Ultrasound scan has gained attention for diagnosing appendicitis due to its avoidance of ionizing radiation. However, studies show that ultrasound scan carries inferior sensitivity to computed tomography scan. A non-diagnostic ultrasound scan could increase the time to diagnosis and appendicectomy, particularly if follow-up computed tomography scan is needed. Some studies suggest that delaying appendicectomy increases the risk of perforation. To investigate the risk of appendiceal perforation when using ultrasound scan as the initial diagnostic imaging modality in children with suspected appendicitis. We retrospectively reviewed 1411 charts of children ≤17 years old diagnosed with appendicitis at two urban academic medical centers. Patients who underwent ultrasound scan first were compared to those who underwent computed tomography scan first. In the sub-group analysis, patients who only received ultrasound scan were compared to those who received initial ultrasound scan followed by computed tomography scan. Main outcome measures were appendiceal perforation rate and time from triage to appendicectomy. In 720 children eligible for analysis, there was no significant difference in perforation rate between those who had initial ultrasound scan and those who had initial computed tomography scan (7.3% vs. 8.9%, p = 0.44), nor in those who had ultrasound scan only and those who had initial ultrasound scan followed by computed tomography scan (8.0% vs. 5.6%, p = 0.42). Those patients who had ultrasound scan first had a shorter triage-to-incision time than those who had computed tomography scan first (9.2 (IQR: 5.9, 14.0) vs. 10.2 (IQR: 7.3, 14.3) hours, p = 0.03), whereas those who had ultrasound scan followed by computed tomography scan took longer than those who had ultrasound scan only (7.8 (IQR: 5.3, 11.6) vs. 15.1 (IQR: 10.6, 20.6), p < 0.001). Children < 12 years old receiving ultrasound scan first had lower perforation rate (p = 0.01) and shorter triage-to-incision time (p = 0.003). Children with suspected appendicitis receiving ultrasound scan as the initial diagnostic imaging modality do not have increased risk of perforation compared to those receiving computed tomography scan first. We recommend that children <12 years of age receive ultrasound scan first.