WorldWideScience

Sample records for source node locations

  1. Lymphatic drainage and sentinel node location in breast cancer

    International Nuclear Information System (INIS)

    Uren, R.F.; Howman-Giles, R.B.; Roberts, J.; Renwick, S.; Gillett, D.; Neische, F.; Ramsay-Stewart, G.

    1999-01-01

    Full text: Mammary lymphoscintigraphy using small volume (0.1-0.2 ml) peritumoral injections of 99 Tc m -antimony sulphide colloid provided a map of the lymph drainage of a breast cancer to its draining sentinel lymph nodes in 92 of 102 patients (over 90%). Non-migration of tracer is reduced by post-injection massage for 5 min but may occur especially if the lymphatics are blocked by metastases. Drainage included the axilla in 92%, internal mammary nodes in 43%, supraclavicular nodes in 12% and intramammary interval nodes in 10% of patients. One patient drained to an interpectoral node. Drainage across the centre-line of the breast occurred in 46% of patients but direct drainage to the contralateral side of the patient was not seen. Lymphatic drainage occurred to 1 node field in 52 patients, 2 node fields in 34 patients and 3 node fields in 6 patients, so that 43% of patients had multiple draining node fields. Drainage to non-axillary sites occurred in 51% of patients. In conclusion, mammary lymphoscintigraphy accurately maps sentinel node location in breast cancer. Approximately half of the patients will have sentinel nodes outside the axilla. To achieve complete lymph node staging in patients with breast cancer, it is logical to biopsy these non-axillary sentinel nodes as well as the sentinel nodes in the axilla. Failure to do so will potentially understage the node status in 50% of patients

  2. The Nodal Location of Metastases in Melanoma Sentinel Lymph Nodes

    DEFF Research Database (Denmark)

    Riber-Hansen, Rikke; Nyengaard, Jens; Hamilton-Dutoit, Stephen

    2009-01-01

    BACKGROUND: The design of melanoma sentinel lymph node (SLN) histologic protocols is based on the premise that most metastases are found in the central parts of the nodes, but the evidence for this belief has never been thoroughly tested. METHODS: The nodal location of melanoma metastases in 149...

  3. Microfluidic ultrasonic particle separators with engineered node locations and geometries

    Science.gov (United States)

    Rose, Klint A.; Fisher, Karl A.; Wajda, Douglas A.; Mariella, Jr., Raymond P.; Bailey, Christopher; Dehlinger, Dietrich; Shusteff, Maxim; Jung, Byoungsok; Ness, Kevin D.

    2016-04-26

    An ultrasonic microfluidic system includes a separation channel for conveying a sample fluid containing small particles and large particles, flowing substantially parallel, adjacent to a recovery fluid, with which it is in contact. An acoustic transducer produces an ultrasound standing wave, that generates a pressure field having at least one node of minimum pressure amplitude. An acoustic extension structure is located proximate to said separation channel for positioning said acoustic node off center in said acoustic area and concentrating the large particles in said recovery fluid stream.

  4. Source and sink nodes in absence seizures.

    Science.gov (United States)

    Rodrigues, Abner C; Machado, Birajara S; Caboclo, Luis Otavio S F; Fujita, Andre; Baccala, Luiz A; Sameshima, Koichi

    2016-08-01

    As opposed to focal epilepsy, absence seizures do not exhibit a clear seizure onset zone or focus since its ictal activity rapidly engages both brain hemispheres. Yet recent graph theoretical analysis applied to absence seizures EEG suggests the cortical focal presence, an unexpected feature for this type of epilepsy. In this study, we explore the characteristics of absence seizure by classifying the nodes as to their source/sink natures via weighted directed graph analysis based on connectivity direction and strength estimation using information partial directed coherence (iPDC). By segmenting the EEG signals into relatively short 5-sec-long time windows we studied the evolution of coupling strengths from both sink and source nodes, and the network dynamics of absence seizures in eight patients.

  5. Geographic Location of a Computer Node Examining a Time-to-Location Algorithm and Multiple Autonomous System Networks

    National Research Council Canada - National Science Library

    Sorgaard, Duane

    2004-01-01

    .... A time-to-location algorithm can successfully resolve a geographic location of a computer node using only latency information from known sites and mathematically calculating the Euclidean distance...

  6. Locating the source of spreading in temporal networks

    Science.gov (United States)

    Huang, Qiangjuan; Zhao, Chengli; Zhang, Xue; Yi, Dongyun

    2017-02-01

    The topological structure of many real networks changes with time. Thus, locating the sources of a temporal network is a creative and challenging problem, as the enormous size of many real networks makes it unfeasible to observe the state of all nodes. In this paper, we propose an algorithm to solve this problem, named the backward temporal diffusion process. The proposed algorithm calculates the shortest temporal distance to locate the transmission source. We assume that the spreading process can be modeled as a simple diffusion process and by consensus dynamics. To improve the location accuracy, we also adopt four strategies to select which nodes should be observed by ranking their importance in the temporal network. Our paper proposes a highly accurate method for locating the source in temporal networks and is, to the best of our knowledge, a frontier work in this field. Moreover, our framework has important significance for controlling the transmission of diseases or rumors and formulating immediate immunization strategies.

  7. Characteristics and locations of sources

    International Nuclear Information System (INIS)

    Lahtinen, J.; Poellaenen, R.; Toivonen, H.

    1997-01-01

    Ten artificial radiation sources were placed in the terrain in order to test the capability of airborne measuring teams to detect them. One of the sources was a line source, others were point sources (three of them collimated). The radionuclides used in the sources were 60 Co, 137 Cs, 99m Tc and 192 Ir. The source activities ranged from about 26 MBq (one of the cobalt sources) to 0.56 TBq (iridium). (au)

  8. Characteristics and locations of sources

    Energy Technology Data Exchange (ETDEWEB)

    Lahtinen, J.; Poellaenen, R.; Toivonen, H. [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland)

    1997-12-31

    Ten artificial radiation sources were placed in the terrain in order to test the capability of airborne measuring teams to detect them. One of the sources was a line source, others were point sources (three of them collimated). The radionuclides used in the sources were {sup 60}Co, {sup 137}Cs, {sup 99m}Tc and {sup 192}Ir. The source activities ranged from about 26 MBq (one of the cobalt sources) to 0.56 TBq (iridium). (au).

  9. Characteristics and locations of sources

    Energy Technology Data Exchange (ETDEWEB)

    Lahtinen, J; Poellaenen, R; Toivonen, H [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland)

    1998-12-31

    Ten artificial radiation sources were placed in the terrain in order to test the capability of airborne measuring teams to detect them. One of the sources was a line source, others were point sources (three of them collimated). The radionuclides used in the sources were {sup 60}Co, {sup 137}Cs, {sup 99m}Tc and {sup 192}Ir. The source activities ranged from about 26 MBq (one of the cobalt sources) to 0.56 TBq (iridium). (au).

  10. Multi-Source Energy Harvesting for Wireless Sensor Nodes.

    OpenAIRE

    Kang, Kai

    2012-01-01

    The past few years have seen an increasing interest in the development of wireless sensor networks. But the unsatisfactory or limited available energy source is one of the major bottlenecks which are limiting the wireless sensor technology from mass deployment. Ambient energy harvesting is the most promising solution towards autonomous sensor nodes by providing low cost, permanent, and maintenance-free energy source to wireless sensor nodes. In this paper, we first invested available energy s...

  11. Solving Minimal Covering Location Problems with Single and Multiple Node Coverage

    Directory of Open Access Journals (Sweden)

    Darko DRAKULIĆ

    2016-12-01

    Full Text Available Location science represents a very attractiveresearch field in combinatorial optimization and it is in expansion in last five decades. The main objective of location problems is determining the best position for facilities in a given set of nodes.Location science includes techniques for modelling problemsand methods for solving them. This paper presents results of solving two types of minimal covering location problems, with single and multiple node coverage, by using CPLEX optimizer and Particle Swarm Optimization method.

  12. One-inch field of view imaging probe for breast cancer sentinel node location

    International Nuclear Information System (INIS)

    D'Errico, Giovanni; Scafe, Raffaele; Soluri, Alessandro; Schiaratura, Alfiero; Maria Mangano, Anna; David, Vincenzo; Scopinaro, Francesco

    2003-01-01

    The already reported 1-in. 2 field of view mini gamma camera known since 1998 with the name of Imaging Probe (IP), has been used for sentinel node localization by a medical equipe that, though trained by the group of nuclear physicians of the University 'La Sapienza' who first conceived and used this detector, has used IP in its own Hospital to: (1) gain experience for future use during operations--a cooperative work on IP radio guided orthopaedic operations has already started working, and (2) to start with IP multicenter trials. In six patients with breast cancer, who underwent lymphoscintigraphy for sentinel node biopsy, sentinel node was checked and located with IP and non-imaging Neoprobe 2000 CdTe (Zn) probe, independent of location by means of large field of view Anger camera. Operators who used Neoprobe and IP were blinded to each other and not aware of the results of Anger camera imaging. Anger camera, as well as IP and neoprobe detected 7 nodes in 6 pts. Detection time was 2', 06'' SD 26'' with IP and 2', 18'' SD 47'' with neoprobe 2000. The most difficult to find node required 2 min and 56 s--inside sd--for IP detection and 3 min and 45 s with neoprobe. Subjective impression of being sure of having detected sentinel node was: absolutely sure on 7/7 nodes with IP and on 5/7 nodes with neoprobe

  13. Source Location of Noble Gas Plumes

    International Nuclear Information System (INIS)

    Hoffman, I.; Ungar, K.; Bourgouin, P.; Yee, E.; Wotawa, G.

    2015-01-01

    In radionuclide monitoring, one of the most significant challenges from a verification or surveillance perspective is the source location problem. Modern monitoring/surveillance systems employ meteorological source reconstruction — for example, the Fukushima accident, CRL emissions analysis and even radon risk mapping. These studies usually take weeks to months to conduct, involving multidisciplinary teams representing meteorology; dispersion modelling; radionuclide sampling and metrology; and, when relevant, proper representation of source characteristics (e.g., reactor engineering expertise). Several different approaches have been tried in an attempt to determine useful techniques to apply to the source location problem and to develop rigorous methods that combine all potentially relevant observations and models to identify a most probable source location and size with uncertainties. The ultimate goal is to understand the utility and limitations of these techniques so they can transition from R&D to operational tools. (author)

  14. Locating industrial VOC sources with aircraft observations

    International Nuclear Information System (INIS)

    Toscano, P.; Gioli, B.; Dugheri, S.; Salvini, A.; Matese, A.; Bonacchi, A.; Zaldei, A.; Cupelli, V.; Miglietta, F.

    2011-01-01

    Observation and characterization of environmental pollution, focussing on Volatile Organic Compounds (VOCs), in a high-risk industrial area, are particularly important in order to provide indications on a safe level of exposure, indicate eventual priorities and advise on policy interventions. The aim of this study is to use the Solid Phase Micro Extraction (SPME) method to measure VOCs, directly coupled with atmospheric measurements taken on a small aircraft environmental platform, to evaluate and locate the presence of VOC emission sources in the Marghera industrial area. Lab analysis of collected SPME fibres and subsequent analysis of mass spectrum and chromatograms in Scan Mode allowed the detection of a wide range of VOCs. The combination of this information during the monitoring campaign allowed a model (Gaussian Plume) to be implemented that estimates the localization of emission sources on the ground. - Highlights: → Flight plan aimed at sampling industrial area at various altitudes and locations. → SPME sampling strategy was based on plume detection by means of CO 2 . → Concentrations obtained were lower than the limit values or below the detection limit. → Scan mode highlighted presence of γ-butyrolactone (GBL) compound. → Gaussian dispersion modelling was used to estimate GBL source location and strength. - An integrated strategy based on atmospheric aircraft observations and dispersion modelling was developed, aimed at estimating spatial location and strength of VOC point source emissions in industrial areas.

  15. Locating noise sources with a microphone array

    International Nuclear Information System (INIS)

    Bale, A.; Johnson, D.

    2010-01-01

    Noise pollution is one of the contributors to the public opposition of wind farms. Most of the noise produced by turbines is caused by the aerodynamic interactions between the turbine blades and the surrounding air. This poster presentation discussed a series of aeroacoustic tests conducted to account for the different in vortical structures caused by the rotation of the blades. Microphone arrays were used measure and locate the source of noise. A beam forming technique was used to measure the noise using an algorithm that identified a scanning grid on a plane where the source was thought to be located. It delayed each microphone's signal by the length of time required for the sound to travel from the scan position to each microphone, and accounted for the amplitudes according to the distance from the scan position to each microphone. Demonstration test cases were conducted using piezo buzzers attached to aluminum bars and mounted to the shaft of a DC motor that produced a rotational diameter of 0.95 meter. The buzzers were placed 1 meter from the array. Multiple sound sources at the same frequency were identified, and the moving sources were accurately measured and located. tabs., figs.

  16. Sound source location in cavitating tip vortices

    International Nuclear Information System (INIS)

    Higuchi, H.; Taghavi, R.; Arndt, R.E.A.

    1985-01-01

    Utilizing an array of three hydrophones, individual cavitation bursts in a tip vortex could be located. Theoretically, four hydrophones are necessary. Hence the data from three hydrophones are supplemented with photographic observation of the cavitating tip vortex. The cavitation sound sources are found to be localized to within one base chord length from the hydrofoil tip. This appears to correspond to the region of initial tip vortex roll-up. A more extensive study with a four sensor array is now in progress

  17. Tremor Source Location at Okmok Volcano

    Science.gov (United States)

    Reyes, C. G.; McNutt, S. R.

    2007-12-01

    Initial results using an amplitude-based tremor location program have located several active tremor episodes under Cone A, a vent within Okmok volcano's 10 km caldera. Okmok is an andesite volcano occupying the north-eastern half of Umnak Island, in the Aleutian islands. Okmok is defined by a ~2000 y.b.p. caldera that contains multiple cinder cones. Cone A, the youngest of these, extruded lava in 1997 covering the caldera floor. Since April 2003, continuous seismic data have been recorded from eight vertical short-period stations (L4-C's) installed at distances from Cone A ranging from 2 km to 31 km. In 2004 four additional 3- component broadband stations were added, co-located with continuous GPS stations. InSAR and GPS measurements of post-eruption deformation show that Okmok experienced several periods of rapid inflation (Mann and Freymueller, 2002), from the center of the 10 km diameter caldera. While there are few locatable VT earthquakes, there has been nearly continuous low-level tremor with stronger amplitude bursts occurring at variable rates and durations. The character of occurrence remained relatively constant over the course of days to weeks until the signal ceased in mid 2005. Within any day, tremor behavior remains fairly consistent, with bursts closely resembling each other, suggesting a single main process or source location. The tremor is composed of irregular waves with a broad range of frequencies, though most energy resides between ~2 Hz and 6 Hz. Attempts to locate the tremor using traditional arrival time methods fail because the signal is emergent, with envelopes too ragged to correlate on time scales that hold much hope for a location. Instead, focus was shifted to the amplitude ratios at various stations. Candidates for the tremor source include the center of inflation and Cone A, 3 km to the south-west. For all dates on record, data were band pass filtered between 1 and 5 Hz, then evaluated in 20.48 second windows (N=2048, sampling rate

  18. Prognostic Significance of the Location of Lymph Node Metastases in Patients With Adenocarcinoma of the Distal Esophagus or Gastroesophageal Junction.

    Science.gov (United States)

    Anderegg, Maarten C J; Lagarde, Sjoerd M; Jagadesham, Vamshi P; Gisbertz, Suzanne S; Immanuel, Arul; Meijer, Sybren L; Hulshof, Maarten C C M; Bergman, Jacques J G H M; van Laarhoven, Hanneke W M; Griffin, S Michael; van Berge Henegouwen, Mark I

    2016-11-01

    To identify the prognostic significance of the location of lymph node metastases in patients with esophageal or gastroesophageal junction (GEJ) adenocarcinoma treated with neoadjuvant therapy followed by esophagectomy. Detection of lymph node metastases in the upper mediastinum and around the celiac trunk after neoadjuvant therapy and resection does not alter the TNM classification of esophageal carcinoma. The impact of these distant lymph node metastases on survival remains unclear. Between March 2003 and September 2013, 479 consecutive patients with adenocarcinoma of the distal esophagus or GEJ who underwent transthoracic esophagectomy with en bloc 2-field lymphadenectomy after neoadjuvant therapy were included, and survival was analyzed according to the location of positive lymph nodes in the resection specimen. Two hundred fifty-three patients had nodal metastases in the resection specimen. Of these patients, 92 patients had metastases in locoregional nodes, 114 patients in truncal nodes, 21 patients in the proximal field of the chest, and 26 patients had both positive truncal and proximal field nodes. Median disease-free survival was 170 months in the absence of nodal metastases, 35 months for metastases limited to locoregional nodes, 16 months for positive truncal nodes, 15 months for positive nodes in the proximal field, and 8 months for nodal metastases in both truncal and the proximal field. On multivariate analysis, location of lymph node metastases was independently associated with survival. Location of lymph node metastases is an independent predictor for survival. Relatively distant lymph node metastases along the celiac axis and/or the proximal field have a negative impact on survival. Location of lymph node metastases should therefore be considered in future staging systems of esophageal and GEJ adenocarcinoma.

  19. Locating the source of diffusion in complex networks by time-reversal backward spreading

    Science.gov (United States)

    Shen, Zhesi; Cao, Shinan; Wang, Wen-Xu; Di, Zengru; Stanley, H. Eugene

    2016-03-01

    Locating the source that triggers a dynamical process is a fundamental but challenging problem in complex networks, ranging from epidemic spreading in society and on the Internet to cancer metastasis in the human body. An accurate localization of the source is inherently limited by our ability to simultaneously access the information of all nodes in a large-scale complex network. This thus raises two critical questions: how do we locate the source from incomplete information and can we achieve full localization of sources at any possible location from a given set of observable nodes. Here we develop a time-reversal backward spreading algorithm to locate the source of a diffusion-like process efficiently and propose a general locatability condition. We test the algorithm by employing epidemic spreading and consensus dynamics as typical dynamical processes and apply it to the H1N1 pandemic in China. We find that the sources can be precisely located in arbitrary networks insofar as the locatability condition is assured. Our tools greatly improve our ability to locate the source of diffusion in complex networks based on limited accessibility of nodal information. Moreover, they have implications for controlling a variety of dynamical processes taking place on complex networks, such as inhibiting epidemics, slowing the spread of rumors, pollution control, and environmental protection.

  20. Prognostic Significance of the Location of Lymph Node Metastases in Patients With Adenocarcinoma of the Distal Esophagus or Gastroesophageal Junction

    NARCIS (Netherlands)

    Anderegg, Maarten C. J.; Lagarde, Sjoerd M.; Jagadesham, Vamshi P.; Gisbertz, Suzanne S.; Immanuel, Arul; Meijer, Sybren L.; Hulshof, Maarten C. C. M.; Bergman, Jacques J. G. H. M.; van Laarhoven, Hanneke W. M.; Griffin, S. Michael; van Berge Henegouwen, Mark I.

    2016-01-01

    To identify the prognostic significance of the location of lymph node metastases in patients with esophageal or gastroesophageal junction (GEJ) adenocarcinoma treated with neoadjuvant therapy followed by esophagectomy. Detection of lymph node metastases in the upper mediastinum and around the celiac

  1. Methods to identify and locate spent radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    The objective of this manual is to provide essential guidance to Member States with nuclear applications involving the use of a wide range of sealed radiation sources on the practical task of physically locating spent radiation sources not properly accounted for. Advice is also provided to render the located source safe on location. Refs, figs and tabs.

  2. Methods to identify and locate spent radiation sources

    International Nuclear Information System (INIS)

    1997-06-01

    The objective of this manual is to provide essential guidance to Member States with nuclear applications involving the use of a wide range of sealed radiation sources on the practical task of physically locating spent radiation sources not properly accounted for. Advice is also provided to render the located source safe on location. Refs, figs, tabs

  3. Methods to identify and locate spent radiation sources

    International Nuclear Information System (INIS)

    1995-07-01

    The objective of this manual is to provide essential guidance to Member States with nuclear applications involving the use of a wide range of sealed radiation sources on the practical task of physically locating spent radiation sources not properly accounted for. Advice is also provided to render the located source safe on location. Refs, figs and tabs

  4. Anatomical location of metastatic lymph nodes: an indispensable prognostic factor for gastric cancer patients who underwent curative resection.

    Science.gov (United States)

    Zhao, Bochao; Zhang, Jingting; Zhang, Jiale; Chen, Xiuxiu; Chen, Junqing; Wang, Zhenning; Xu, Huimian; Huang, Baojun

    2018-02-01

    Although the numeric-based lymph node (LN) staging was widely used in the worldwide, it did not represent the anatomical location of metastatic lymph nodes (MLNs) and not reflect extent of LN dissection. Therefore, in the present study, we investigated whether the anatomical location of MLNs was still necessary to evaluate the prognosis of node-positive gastric cancer (GC) patients. We reviewed 1451 GC patients who underwent radical gastrectomy in our institution between January 1986 and January 2008. All patients were reclassified into several groups according to the anatomical location of MLNs and the number of MLNs. The prognostic differences between different patient groups were compared and clinicopathologic features were analyzed. In the present study, both anatomical location of MLNs and the number of MLNs were identified as the independent prognostic factors (p location of MLNs was considered (p location of MLNs had no significant effect on the prognosis of these patients, the higher number of MLNs in the extraperigastric area was correlated with the unfavorable prognosis (p location of MLNs was an important factor influencing the prognostic outcome of GC patients. To provide more accurate prognostic information for GC patients, the anatomical location of MLNs should not be ignored.

  5. Sign of Radon for locate geothermic sources

    International Nuclear Information System (INIS)

    Gonzalez Teran, D.

    1991-01-01

    Evaluation of a geothermic field is based upon geological, geophysical and geochemical studies that enable the evaluation of the deposit potential, that is to say, the amount of energy per unit mass, the volume of the trapped fluid, vapor fraction and fluid chemistry. This thesis has as its objective the evaluation of radon gas emanation in high potential geothermic zones in order to utilize the results as a low cost and easy to manage complimentary tool in geothermic source prospection. In chapter I the importance and evaluation of a geothermic deposit is discussed. In chapter II the general characteristics of radon are discussed: its radioactivity and behavior upon diffusion over the earth's surface> Chapter III establishes the approach used in the geothermic field of Los Azufres, Michoacan, to carry out samplings of radon and the laboratory techniques that were used to evaluate the concentration of radon in the subsoil. Finally in chapter IV measurements of radon in the field are compared to geological faults in the area under study. The sampling zones were: low geothermic potential zone of the northern and the southern zone having a greater geothermic potential than that in the north. The study was carried out at different sampling times using plastics detectors of from 30 to 46 days from February to July. From the results obtained we concluded that the emission of radon was greater in the zones of greatest geothermic potential than in the low geothermic potential zones it was also affected by the fault structure and the time of year in which sampling was done. (Author)

  6. Enhancing source location protection in wireless sensor networks

    Science.gov (United States)

    Chen, Juan; Lin, Zhengkui; Wu, Di; Wang, Bailing

    2015-12-01

    Wireless sensor networks are widely deployed in the internet of things to monitor valuable objects. Once the object is monitored, the sensor nearest to the object which is known as the source informs the base station about the object's information periodically. It is obvious that attackers can capture the object successfully by localizing the source. Thus, many protocols have been proposed to secure the source location. However, in this paper, we examine that typical source location protection protocols generate not only near but also highly localized phantom locations. As a result, attackers can trace the source easily from these phantom locations. To address these limitations, we propose a protocol to enhance the source location protection (SLE). With phantom locations far away from the source and widely distributed, SLE improves source location anonymity significantly. Theory analysis and simulation results show that our SLE provides strong source location privacy preservation and the average safety period increases by nearly one order of magnitude compared with existing work with low communication cost.

  7. Ambiguity of source location in acoustic emission technique

    International Nuclear Information System (INIS)

    Barat, P.; Mukherjee, P.; Kalyanasundaram, P.; Raj, B.

    1996-01-01

    Location of acoustic emission (AE) source in a plane is detected from the difference of the arrival times of the AE signal to at least three sensors placed on it. The detected location may not be unique in all cases. In this paper, the condition for the unambiguous solution for the location of the source has been deduced mathematically in terms of arrival times of the AE signal, the coordinate of the three sensors and the acoustic velocity. (author)

  8. MUSIC algorithm DoA estimation for cooperative node location in mobile ad hoc networks

    Science.gov (United States)

    Warty, Chirag; Yu, Richard Wai; ElMahgoub, Khaled; Spinsante, Susanna

    In recent years the technological development has encouraged several applications based on distributed communications network without any fixed infrastructure. The problem of providing a collaborative early warning system for multiple mobile nodes against a fast moving object. The solution is provided subject to system level constraints: motion of nodes, antenna sensitivity and Doppler effect at 2.4 GHz and 5.8 GHz. This approach consists of three stages. The first phase consists of detecting the incoming object using a highly directive two element antenna at 5.0 GHz band. The second phase consists of broadcasting the warning message using a low directivity broad antenna beam using 2× 2 antenna array which then in third phase will be detected by receiving nodes by using direction of arrival (DOA) estimation technique. The DOA estimation technique is used to estimate the range and bearing of the incoming nodes. The position of fast arriving object can be estimated using the MUSIC algorithm for warning beam DOA estimation. This paper is mainly intended to demonstrate the feasibility of early detection and warning system using a collaborative node to node communication links. The simulation is performed to show the behavior of detecting and broadcasting antennas as well as performance of the detection algorithm. The idea can be further expanded to implement commercial grade detection and warning system

  9. Geographic Location of a Computer Node Examining a Time-to-Location Algorithm and Multiple Autonomous System Networks

    National Research Council Canada - National Science Library

    Sorgaard, Duane

    2004-01-01

    To determine the location of a computer on the Internet without resorting to outside information or databases would greatly increase the security abilities of the US Air Force and the Department of Defense...

  10. Acoustic wavefield evolution as a function of source location perturbation

    KAUST Repository

    Alkhalifah, Tariq Ali

    2010-12-01

    The wavefield is typically simulated for seismic exploration applications through solving the wave equation for a specific seismic source location. The direct relation between the form (or shape) of the wavefield and the source location can provide insights useful for velocity estimation and interpolation. As a result, I derive partial differential equations that relate changes in the wavefield shape to perturbations in the source location, especially along the Earth\\'s surface. These partial differential equations have the same structure as the wave equation with a source function that depends on the background (original source) wavefield. The similarity in form implies that we can use familiar numerical methods to solve the perturbation equations, including finite difference and downward continuation. In fact, we can use the same Green\\'s function to solve the wave equation and its source perturbations by simply incorporating source functions derived from the background field. The solutions of the perturbation equations represent the coefficients of a Taylor\\'s series type expansion of the wavefield as a function of source location. As a result, we can speed up the wavefield calculation as we approximate the wavefield shape for sources in the vicinity of the original source. The new formula introduces changes to the background wavefield only in the presence of lateral velocity variation or in general terms velocity variations in the perturbation direction. The approach is demonstrated on the smoothed Marmousi model.

  11. Wavefield dependency on virtual shifts in the source location

    KAUST Repository

    Alkhalifah, Tariq

    2011-01-01

    shape) to lateral perturbations in the source location depends explicitly on lateral derivatives of the velocity field. For velocity models that include lateral velocity discontinuities this is problematic as such derivatives in their classical

  12. 48 CFR 319.202-2 - Locating small business sources.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Locating small business... SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS Policies 319.202-2 Locating small business sources. (a) OPDIVs shall foster, to the extent practicable, maximum participation by small businesses in HHS acquisitions...

  13. 48 CFR 2919.202-2 - Locating small business sources.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Locating small business... SOCIOECONOMIC PROGRAMS SMALL BUSINESS AND SMALL DISADVANTAGED BUSINESS CONCERNS Policies 2919.202-2 Locating small business sources. Any procurement conducted on an unrestricted basis will include solicitations to...

  14. 48 CFR 19.202-2 - Locating small business sources.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Locating small business... SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS Policies 19.202-2 Locating small business sources. The contracting officer must, to the extent practicable, encourage maximum participation by small business...

  15. Method to Locate Contaminant Source and Estimate Emission Strength

    Directory of Open Access Journals (Sweden)

    Qu Hongquan

    2013-01-01

    Full Text Available People greatly concern the issue of air quality in some confined spaces, such as spacecraft, aircraft, and submarine. With the increase of residence time in such confined space, contaminant pollution has become a main factor which endangers life. It is urgent to identify a contaminant source rapidly so that a prompt remedial action can be taken. A procedure of source identification should be able to locate the position and to estimate the emission strength of the contaminant source. In this paper, an identification method was developed to realize these two aims. This method was developed based on a discrete concentration stochastic model. With this model, a sensitivity analysis algorithm was induced to locate the source position, and a Kalman filter was used to further estimate the contaminant emission strength. This method could track and predict the source strength dynamically. Meanwhile, it can predict the distribution of contaminant concentration. Simulation results have shown the virtues of the method.

  16. Influence of external source location in the reactivity calculation

    International Nuclear Information System (INIS)

    Silva, Adilson Costa da; Silva, Fernando Carvalho da; Martinez, Aquilino Senra

    2011-01-01

    We used the neutron diffusion equation with external neutron sources, in cartesian geometry and the two groups of energy, to verify the influence of external neutron source locations in the reactivity calculation. For this, a coarse mesh finite difference method was developed for the adjoint flux calculation and simplifies reactivity calculation in PWR type reactor, which uses the output of the nodal expansion method. The results were obtained for different locations on the two-dimensional plane, as well as for different types of fuel elements in the reactor core. (author)

  17. Influence of external source location in the reactivity calculation

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Adilson Costa da; Silva, Fernando Carvalho da; Martinez, Aquilino Senra, E-mail: asilva@con.ufrj.b, E-mail: fernando@con.ufrj.b, E-mail: Aquilino@lmp.ufrj.b [Coordenacao dos Programas de Pos-Graduacao de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear

    2011-07-01

    We used the neutron diffusion equation with external neutron sources, in cartesian geometry and the two groups of energy, to verify the influence of external neutron source locations in the reactivity calculation. For this, a coarse mesh finite difference method was developed for the adjoint flux calculation and simplifies reactivity calculation in PWR type reactor, which uses the output of the nodal expansion method. The results were obtained for different locations on the two-dimensional plane, as well as for different types of fuel elements in the reactor core. (author)

  18. Learning to locate an odour source with a mobile robot

    OpenAIRE

    Duckett, T.; Axelsson, M.; Saffiotti, A.

    2001-01-01

    We address the problem of enabling a mobile robot to locate a stationary odour source using an electronic nose constructed from gas sensors. On the hardware side, we use a stereo nose architecture consisting of two parallel chambers, each containing an identical set of sensors. On the software side, we use a recurrent artificial neural network to learn the direction to a stationary source from a time series of sensor readings. This contrasts with previous approaches, that rely on the existenc...

  19. A Comparative Study Of Source Location And Depth Estimates From ...

    African Journals Online (AJOL)

    ... the analytic signal amplitude (ASA) and the local wave number (LWN) of the total intensity magnetic field. In this study, a synthetic magnetic field due to four buried dipoles was analysed to show that estimates of source location and depth can be improved significantly by reducing the data to the pole prior to the application ...

  20. An inverse source location algorithm for radiation portal monitor applications

    International Nuclear Information System (INIS)

    Miller, Karen A.; Charlton, William S.

    2010-01-01

    Radiation portal monitors are being deployed at border crossings throughout the world to prevent the smuggling of nuclear and radiological materials; however, a tension exists between security and the free-flow of commerce. Delays at ports-of-entry have major economic implications, so it is imperative to minimize portal monitor screening time. We have developed an algorithm to locate a radioactive source using a distributed array of detectors, specifically for use at border crossings. To locate the source, we formulated an optimization problem where the objective function describes the least-squares difference between the actual and predicted detector measurements. The predicted measurements are calculated by solving the 3-D deterministic neutron transport equation given an estimated source position. The source position is updated using the steepest descent method, where the gradient of the objective function with respect to the source position is calculated using adjoint transport calculations. If the objective function is smaller than the convergence criterion, then the source position has been identified. This paper presents the derivation of the underlying equations in the algorithm as well as several computational test cases used to characterize its accuracy.

  1. Cartilage immunoprivilege depends on donor source and lesion location.

    Science.gov (United States)

    Arzi, B; DuRaine, G D; Lee, C A; Huey, D J; Borjesson, D L; Murphy, B G; Hu, J C Y; Baumgarth, N; Athanasiou, K A

    2015-09-01

    The ability to repair damaged cartilage is a major goal of musculoskeletal tissue engineering. Allogeneic (same species, different individual) or xenogeneic (different species) sources can provide an attractive source of chondrocytes for cartilage tissue engineering, since autologous (same individual) cells are scarce. Immune rejection of non-autologous hyaline articular cartilage has seldom been considered due to the popular notion of "cartilage immunoprivilege". The objective of this study was to determine the suitability of allogeneic and xenogeneic engineered neocartilage tissue for cartilage repair. To address this, scaffold-free tissue engineered articular cartilage of syngeneic (same genetic background), allogeneic, and xenogeneic origin were implanted into two different locations of the rabbit knee (n=3 per group/location). Xenogeneic engineered cartilage and control xenogeneic chondral explants provoked profound innate inflammatory and adaptive cellular responses, regardless of transplant location. Cytological quantification of immune cells showed that, while allogeneic neocartilage elicited an immune response in the patella, negligible responses were observed when implanted into the trochlea; instead the responses were comparable to microfracture-treated empty defect controls. Allogeneic neocartilage survived within the trochlea implant site and demonstrated graft integration into the underlying bone. In conclusion, the knee joint cartilage does not represent an immune privileged site, strongly rejecting xenogeneic but not allogeneic chondrocytes in a location-dependent fashion. This difference in location-dependent survival of allogeneic tissue may be associated with proximity to the synovium. Through a series of in vivo studies this research demonstrates that articular cartilage is not fully immunoprivileged. In addition, we now show that anatomical location of the defect, even within the same joint compartment, strongly influences the degree of the

  2. Location of an electric source facility and local area promotion

    International Nuclear Information System (INIS)

    Shimohirao, Isao

    1999-01-01

    Here were described on energy demand and supply, energy policy and local area promotion policy for basic problems important on location of electric source facilities. At present, co-existence business between electricity business and electric source location area is lacking in its activity. It seems to be necessary to enforce some systems to intend to promote it earnestly, and to effort to promote industry promotions such as introduction of some national projects, induction of electricity cost reduction for a means of business invitation, and so forth. And it is necessary to promote them under cooperations with electricity businesses, governments, universities and communities for the industrial promotion and fixation of the youth at local areas. In order to realize such necessities, further larger efforts are expected for national and local governments. (G.K.)

  3. Towards an accurate real-time locator of infrasonic sources

    Science.gov (United States)

    Pinsky, V.; Blom, P.; Polozov, A.; Marcillo, O.; Arrowsmith, S.; Hofstetter, A.

    2017-11-01

    Infrasonic signals propagate from an atmospheric source via media with stochastic and fast space-varying conditions. Hence, their travel time, the amplitude at sensor recordings and even manifestation in the so-called "shadow zones" are random. Therefore, the traditional least-squares technique for locating infrasonic sources is often not effective, and the problem for the best solution must be formulated in probabilistic terms. Recently, a series of papers has been published about Bayesian Infrasonic Source Localization (BISL) method based on the computation of the posterior probability density function (PPDF) of the source location, as a convolution of a priori probability distribution function (APDF) of the propagation model parameters with likelihood function (LF) of observations. The present study is devoted to the further development of BISL for higher accuracy and stability of the source location results and decreasing of computational load. We critically analyse previous algorithms and propose several new ones. First of all, we describe the general PPDF formulation and demonstrate that this relatively slow algorithm might be among the most accurate algorithms, provided the adequate APDF and LF are used. Then, we suggest using summation instead of integration in a general PPDF calculation for increased robustness, but this leads us to the 3D space-time optimization problem. Two different forms of APDF approximation are considered and applied for the PPDF calculation in our study. One of them is previously suggested, but not yet properly used is the so-called "celerity-range histograms" (CRHs). Another is the outcome from previous findings of linear mean travel time for the four first infrasonic phases in the overlapping consecutive distance ranges. This stochastic model is extended here to the regional distance of 1000 km, and the APDF introduced is the probabilistic form of the junction between this travel time model and range-dependent probability

  4. AE source location by neural networks with arrival time profiles

    Czech Academy of Sciences Publication Activity Database

    Chlada, Milan; Blaháček, Michal; Převorovský, Zdeněk

    2009-01-01

    Roč. 19, č. 2 (2009), s. 4-4 ISSN 1213-3825. [NDT in PROGRESS. 12.11.2009-14.11.2009, Praha] R&D Projects: GA ČR GA101/07/1518; GA ČR GA106/07/1393 Institutional research plan: CEZ:AV0Z20760514 Keywords : acoustic emission * source location * artificial neural networks Subject RIV: BI - Acoustics www.cndt.cz

  5. Locating Microseism Sources Using Spurious Arrivals in Intercontinental Noise Correlations

    Science.gov (United States)

    Retailleau, Lise; Boué, Pierre; Stehly, Laurent; Campillo, Michel

    2017-10-01

    The accuracy of Green's functions retrieved from seismic noise correlations in the microseism frequency band is limited by the uneven distribution of microseism sources at the surface of the Earth. As a result, correlation functions are often biased as compared to the expected Green's functions, and they can include spurious arrivals. These spurious arrivals are seismic arrivals that are visible on the correlation and do not belong to the theoretical impulse response. In this article, we propose to use Rayleigh wave spurious arrivals detected on correlation functions computed between European and United States seismic stations to locate microseism sources in the Atlantic Ocean. We perform a slant stack on a time distance gather of correlations obtained from an array of stations that comprises a regional deployment and a distant station. The arrival times and the apparent slowness of the spurious arrivals lead to the location of their source, which is obtained through a grid search procedure. We discuss improvements in the location through this methodology as compared to classical back projection of microseism energy. This method is interesting because it only requires an array and a distant station on each side of an ocean, conditions that can be met relatively easily.

  6. Wavefield dependency on virtual shifts in the source location

    KAUST Repository

    Alkhalifah, Tariq

    2011-02-14

    The wavefield dependence on a virtual shift in the source location can provide information helpful in velocity estimation and interpolation. However, the second-order partial differential equation (PDE) that relates changes in the wavefield form (or shape) to lateral perturbations in the source location depends explicitly on lateral derivatives of the velocity field. For velocity models that include lateral velocity discontinuities this is problematic as such derivatives in their classical definition do not exist. As a result, I derive perturbation partial differential wave equations that are independent of direct velocity derivatives and thus, provide possibilities for wavefield shape extrapolation in complex media. These PDEs have the same structure as the wave equation with a source function that depends on the background (original source) wavefield. The solutions of the perturbation equations provide the coefficients of a Taylor\\'s series type expansion for the wavefield. The new formulas introduce changes to the background wavefield only in the presence of lateral velocity variation or in general terms velocity variations in the perturbation direction. The accuracy of the representation, as demonstrated on the Marmousi model, is generally good. © 2011 European Association of Geoscientists & Engineers.

  7. THE PROGNOSIS SIGNIFICANCE OF CATHEPSIN-D EXPRESSION IN THE DIFFERENT LOCATIONS IN AXILLARY NODES NEGATIVE CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: The aim of this study was to investigate Cathepsin-D (Cath-D) expression in different location and its relationship with prognosis in the axillary lymph nodes negative (ANN) breast cancer patients. Methods: Cath-D expression in 192 cases of breast carcinoma were examined by immunohistochemistry. Depending on different parts of expression, three evaluating methods were used, compared and analysed. Results: The positive rate of Cath-D expression in ANN breast cancer with poor prognosis group and axillary nodes positive (ANP) group were significantly higher than that in ANN breast cancer with good prognosis group (x2=23.20, P0.05). Cath-D expression in stromal cells had no statistical difference among the three groups (x2=1.56, P>0.05). When the Cath-D expression in cancer and stromal cells were counted into the positive rate, it was near the same (u1=0.47, u2=1.41, P>0.05). Conclusion: These results suggest that Cath-D expression is one of the powerful prognostic markers in ANN breast cancer. It's a reliable, practical, and convenient method to observe and evaluate Cath-D expression in cancer cells.

  8. Detection, Source Location, and Analysis of Volcano Infrasound

    Science.gov (United States)

    McKee, Kathleen F.

    The study of volcano infrasound focuses on low frequency sound from volcanoes, how volcanic processes produce it, and the path it travels from the source to our receivers. In this dissertation we focus on detecting, locating, and analyzing infrasound from a number of different volcanoes using a variety of analysis techniques. These works will help inform future volcano monitoring using infrasound with respect to infrasonic source location, signal characterization, volatile flux estimation, and back-azimuth to source determination. Source location is an important component of the study of volcano infrasound and in its application to volcano monitoring. Semblance is a forward grid search technique and common source location method in infrasound studies as well as seismology. We evaluated the effectiveness of semblance in the presence of significant topographic features for explosions of Sakurajima Volcano, Japan, while taking into account temperature and wind variations. We show that topographic obstacles at Sakurajima cause a semblance source location offset of 360-420 m to the northeast of the actual source location. In addition, we found despite the consistent offset in source location semblance can still be a useful tool for determining periods of volcanic activity. Infrasonic signal characterization follows signal detection and source location in volcano monitoring in that it informs us of the type of volcanic activity detected. In large volcanic eruptions the lowermost portion of the eruption column is momentum-driven and termed the volcanic jet or gas-thrust zone. This turbulent fluid-flow perturbs the atmosphere and produces a sound similar to that of jet and rocket engines, known as jet noise. We deployed an array of infrasound sensors near an accessible, less hazardous, fumarolic jet at Aso Volcano, Japan as an analogue to large, violent volcanic eruption jets. We recorded volcanic jet noise at 57.6° from vertical, a recording angle not normally feasible

  9. Locating gamma radiation source by self collimating BGO detector system

    Energy Technology Data Exchange (ETDEWEB)

    Orion, I; Pernick, A; Ilzycer, D; Zafrir, H [Israel Atomic Energy Commission, Yavne (Israel). Soreq Nuclear Research Center; Shani, G [Ben-Gurion Univ. of the Negev, Beersheba (Israel)

    1996-12-01

    The need for airborne collimated gamma detector system to estimate the radiation released from a nuclear accident has been established. A BGO detector system has been developed as an array of separate seven cylindrical Bismuth Germanate scintillators, one central detector symmetrically surrounded by six detectors. In such an arrangement, each of the detectors reduced the exposure of other detectors in the array to a radiation incident from a possible specific spatial angle, around file array. This shielding property defined as `self-collimation`, differs the point source response function for each of the detectors. The BGO detector system has a high density and atomic number, and therefore provides efficient self-collimation. Using the response functions of the separate detectors enables locating point sources as well as the direction of a nuclear radioactive plume with satisfactory angular resolution, of about 10 degrees. The detector`s point source response, as function of the source direction, in a horizontal plane, has been predicted by analytical calculation, and was verified by Monte-Carlo simulation using the code EGS4. The detector`s response was tested in a laboratory-scale experiment for several gamma ray energies, and the experimental results validated the theoretical (analytical and Monte-Carlo) results. (authors).

  10. Simultaneous head tissue conductivity and EEG source location estimation.

    Science.gov (United States)

    Akalin Acar, Zeynep; Acar, Can E; Makeig, Scott

    2016-01-01

    Accurate electroencephalographic (EEG) source localization requires an electrical head model incorporating accurate geometries and conductivity values for the major head tissues. While consistent conductivity values have been reported for scalp, brain, and cerebrospinal fluid, measured brain-to-skull conductivity ratio (BSCR) estimates have varied between 8 and 80, likely reflecting both inter-subject and measurement method differences. In simulations, mis-estimation of skull conductivity can produce source localization errors as large as 3cm. Here, we describe an iterative gradient-based approach to Simultaneous tissue Conductivity And source Location Estimation (SCALE). The scalp projection maps used by SCALE are obtained from near-dipolar effective EEG sources found by adequate independent component analysis (ICA) decomposition of sufficient high-density EEG data. We applied SCALE to simulated scalp projections of 15cm(2)-scale cortical patch sources in an MR image-based electrical head model with simulated BSCR of 30. Initialized either with a BSCR of 80 or 20, SCALE estimated BSCR as 32.6. In Adaptive Mixture ICA (AMICA) decompositions of (45-min, 128-channel) EEG data from two young adults we identified sets of 13 independent components having near-dipolar scalp maps compatible with a single cortical source patch. Again initialized with either BSCR 80 or 25, SCALE gave BSCR estimates of 34 and 54 for the two subjects respectively. The ability to accurately estimate skull conductivity non-invasively from any well-recorded EEG data in combination with a stable and non-invasively acquired MR imaging-derived electrical head model could remove a critical barrier to using EEG as a sub-cm(2)-scale accurate 3-D functional cortical imaging modality. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Study of Coal Burst Source Locations in the Velenje Colliery

    Directory of Open Access Journals (Sweden)

    Goran Vižintin

    2016-06-01

    Full Text Available The Velenje coal mine (VCM is situated on the largest Slovenian coal deposit and in one of the thickest layers of coal known in the world. The thickness of the coal layer causes problems for the efficiency of extraction, since the majority of mining operations is within the coal layer. The selected longwall coal mining method with specific geometry, increasing depth of excavations, changes in stress state and naturally given geomechanical properties of rocks induce seismic events. Induced seismic events can be caused by caving processes, blasting or bursts of coal or the surrounding rock. For 2.5D visualization, data of excavations, ash content and calorific value of coal samples, hanging wall and footwall occurrence, subsidence of the surface and coal burst source locations were collected. Data and interpolation methods available in software package Surfer®12 were statistically analyzed and a Kriging (KRG interpolation method was chosen. As a result 2.5D visualizations of coal bursts source locations with geomechanical properties of coal samples taken at different depth in the coal seam in the VCM were made with data-visualization packages Surfer®12 and Voxler®3.

  12. Rapidly locating sources and predicting contaminant dispersion in buildings

    International Nuclear Information System (INIS)

    Sohn, Michael D.; Reynolds, Pamela; Gadgil, Ashok J.; Sextro, Richard G.

    2002-01-01

    Contaminant releases in or near a building can lead to significant human exposures unless prompt response measures are taken. However, selecting the proper response depends in part on knowing the source locations, the amounts released, and the dispersion characteristics of the pollutants. We present an approach that estimates this information in real time. It uses Bayesian statistics to interpret measurements from sensors placed in the building yielding best estimates and uncertainties for the release conditions, including the operating state of the building. Because the method is fast, it continuously updates the estimates as measurements stream in from the sensors. We show preliminary results for characterizing a gas release in a three-floor, multi-room building at the Dugway Proving Grounds, Utah, USA

  13. Continuous wavelet transform analysis and modal location analysis acoustic emission source location for nuclear piping crack growth monitoring

    International Nuclear Information System (INIS)

    Shukri Mohd

    2013-01-01

    Full-text: Source location is an important feature of acoustic emission (AE) damage monitoring in nuclear piping. The ability to accurately locate sources can assist in source characterisation and early warning of failure. This paper describe the development of a novelAE source location technique termed Wavelet Transform analysis and Modal Location (WTML) based on Lamb wave theory and time-frequency analysis that can be used for global monitoring of plate like steel structures. Source location was performed on a steel pipe of 1500 mm long and 220 mm outer diameter with nominal thickness of 5 mm under a planar location test setup using H-N sources. The accuracy of the new technique was compared with other AE source location methods such as the time of arrival (TOA) technique and DeltaTlocation. The results of the study show that the WTML method produces more accurate location results compared with TOA and triple point filtering location methods. The accuracy of the WTML approach is comparable with the deltaT location method but requires no initial acoustic calibration of the structure. (author)

  14. Continuous wavelet transform analysis and modal location analysis acoustic emission source location for nuclear piping crack growth monitoring

    International Nuclear Information System (INIS)

    Mohd, Shukri; Holford, Karen M.; Pullin, Rhys

    2014-01-01

    Source location is an important feature of acoustic emission (AE) damage monitoring in nuclear piping. The ability to accurately locate sources can assist in source characterisation and early warning of failure. This paper describe the development of a novelAE source location technique termed 'Wavelet Transform analysis and Modal Location (WTML)' based on Lamb wave theory and time-frequency analysis that can be used for global monitoring of plate like steel structures. Source location was performed on a steel pipe of 1500 mm long and 220 mm outer diameter with nominal thickness of 5 mm under a planar location test setup using H-N sources. The accuracy of the new technique was compared with other AE source location methods such as the time of arrival (TOA) techniqueand DeltaTlocation. Theresults of the study show that the WTML method produces more accurate location resultscompared with TOA and triple point filtering location methods. The accuracy of the WTML approach is comparable with the deltaT location method but requires no initial acoustic calibration of the structure

  15. Continuous wavelet transform analysis and modal location analysis acoustic emission source location for nuclear piping crack growth monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Mohd, Shukri [Nondestructive Testing Group, Industrial Technology Division, Malaysian Nuclear Agency, 43000, Bangi, Selangor (Malaysia); Holford, Karen M.; Pullin, Rhys [Cardiff School of Engineering, Cardiff University, Queen' s Buildings, The Parade, CARDIFF CF24 3AA (United Kingdom)

    2014-02-12

    Source location is an important feature of acoustic emission (AE) damage monitoring in nuclear piping. The ability to accurately locate sources can assist in source characterisation and early warning of failure. This paper describe the development of a novelAE source location technique termed 'Wavelet Transform analysis and Modal Location (WTML)' based on Lamb wave theory and time-frequency analysis that can be used for global monitoring of plate like steel structures. Source location was performed on a steel pipe of 1500 mm long and 220 mm outer diameter with nominal thickness of 5 mm under a planar location test setup using H-N sources. The accuracy of the new technique was compared with other AE source location methods such as the time of arrival (TOA) techniqueand DeltaTlocation. Theresults of the study show that the WTML method produces more accurate location resultscompared with TOA and triple point filtering location methods. The accuracy of the WTML approach is comparable with the deltaT location method but requires no initial acoustic calibration of the structure.

  16. Source location of chorus emissions observed by Cluster

    Directory of Open Access Journals (Sweden)

    M. Parrot

    Full Text Available One of the objectives of the Cluster mission is to study sources of various electromagnetic waves using the four satellites. This paper describes the methods we have applied to data recorded from the STAFF spectrum analyser. This instrument provides the cross spectral matrix of three magnetic and two electric field components. This spectral matrix is analysed to determine, for each satellite, the direction of the wave normal relative to the Earth’s magnetic field as a function of frequency and of time. Due to the Cluster orbit, chorus emissions are often observed close to perigee, and the data analysis determines the direction of these waves. Three events observed during different levels of magnetic activity are reported. It is shown that the component of the Poynting vector parallel to the magnetic field changes its sense when the satellites cross the magnetic equator, which indicates that the chorus waves propagate away from the equator. Detailed analysis indicates that the source is located in close vicinity of the plane of the geomagnetic equator.

    Key words. Magnetospheric physics (plasma waves and instabilities; storms and substorms; Space plasma physics (waves and instabilities

  17. Bony landmarks are not an adequate substitute for lymphangiography in defining pelvic lymph node location for the treatment of cervical cancer with radiotherapy

    International Nuclear Information System (INIS)

    Bonin, Steven R.; Lanciano, Rachelle M.; Corn, Benjamin W.; Hogan, W. Michael; Hartz, William H.; Hanks, Gerald E.

    1996-01-01

    cm from the previously described reference line had mean values of 2.0 ± 1.0 cm (range 1.3 to 3.0 cm), 0.9 ± 3.9 cm (range -1.9 to 5.1 cm), and 1.8 ± 2.1 cm (range -0.8 to 3.5 cm), respectively. Ten of 22 (45%) patients would have had inadequate nodal irradiation if their fields had been designed according to standard GOG parameters. In all cases, these incompletely irradiated lymph nodes were from the lowest of the lateral external iliac group. Conclusions: Great variability in pelvic lymph node location is demonstrated when LAG is used to directly visualize their location. Bony structures are inaccurate landmarks for pelvic lymph node position. The GOG standard pelvic fields are not consistently adequate to cover all lateral external iliac lymph nodes, although the clinical significance of this subgroup of lymph nodes is not known. At this time, LAG remains the ideal radiographic modality to define anatomic location of regional lymph nodes for pelvic RT treatment planning. The clinical importance of the most lateral group of external iliac lymph nodes in various stages of cervical cancer represents a potential area of future research

  18. Clinical Significance of Lymph Node Metastasis in the Mesentery of the Terminal Ileum in Patients With Right-sided Colon Tumors at Different Locations.

    Science.gov (United States)

    Kang, Sung Il; Kim, Duck-Woo; Shin, Eun; Kim, Myung Jo; Son, Il Tae; Oh, Heung-Kwon; Kang, Sung-Bum

    2018-06-01

    There are limited reports on peri-ileal lymph node metastasis in patients with right-sided colon cancer, and little is known about their clinical significance. This study aimed to examine the role of tumor location in the prevalence and clinical significance of peri-ileal lymph node metastasis in patients with right-sided colon cancer. This is a retrospective study from a prospective cohort database. The study was conducted at a tertiary referral hospital. Patients with right-sided colon cancer treated with radical surgery in a hospital between May 2006 and September 2016 were included. The frequency of peri-ileal lymph node metastasis in the study cohort and the role of tumor location and the clinical characteristics of patients with peri-ileal lymph node metastasis were determined. We examined 752 cases with right-sided colon cancer including 82 cecal, 554 ascending colon, and 116 hepatic flexure cancer. Twenty patients (2.7%) had peri-ileal lymph node metastasis. The incidence of metastasis to peri-ileal lymph nodes was 7.3% (6/82) in patients with cecal cancer, 2.2% (12/554) in patients with ascending colon cancer, and 1.7% (2/116) in patients with hepatic flexure cancer. Three patients had stage III cancer and 17 had stage IV. All 3 patients with positive peri-ileal lymph nodes and stage III cancer had cecal tumors. In contrast, all patients with ascending colon or hepatic flexure cancer and positive peri-ileal lymph nodes had stage IV cancer. The results were limited by the retrospective design of the study and the small number of patients with peri-ileal lymph node metastasis. Peri-ileal lymph node metastasis was rare even in right-sided colon cancer and occurred mainly in stage IV. However, it occurred in some patients with locally advanced cecal cancer. These results suggest that optimal resection of the mesentery of the terminal ileum might have clinical benefit, especially in curative surgery for cecal cancer. See Video Abstract at http

  19. Acoustic wavefield evolution as a function of source location perturbation

    KAUST Repository

    Alkhalifah, Tariq Ali

    2010-01-01

    differential equations have the same structure as the wave equation with a source function that depends on the background (original source) wavefield. The similarity in form implies that we can use familiar numerical methods to solve the perturbation equations

  20. Long Period (LP) volcanic earthquake source location at Merapi volcano by using dense array technics

    Science.gov (United States)

    Metaxian, Jean Philippe; Budi Santoso, Agus; Laurin, Antoine; Subandriyo, Subandriyo; Widyoyudo, Wiku; Arshab, Ghofar

    2015-04-01

    Since 2010, Merapi shows unusual activity compared to last decades. Powerful phreatic explosions are observed; some of them are preceded by LP signals. In the literature, LP seismicity is thought to be originated within the fluid, and therefore to be representative of the pressurization state of the volcano plumbing system. Another model suggests that LP events are caused by slow, quasi-brittle, low stress-drop failure driven by transient upper-edifice deformations. Knowledge of the spatial distribution of LP events is fundamental for better understanding the physical processes occurring in the conduit, as well as for the monitoring and the improvement of eruption forecasting. LP events recorded at Merapi have a spectral content dominated by frequencies between 0.8 and 3 Hz. To locate the source of these events, we installed a seismic antenna composed of 4 broadband CMG-6TD Güralp stations. This network has an aperture of 300 m. It is located on the site of Pasarbubar, between 500 and 800 m from the crater rim. Two multi-parameter stations (seismic, tiltmeter, S-P) located in the same area, equipped with broadband CMG-40T Güralp sensors may also be used to complete the data of the antenna. The source of LP events is located by using different approaches. In the first one, we used a method based on the measurement of the time delays between the early beginnings of LP events for each array receiver. The observed differences of time delays obtained for each pair of receivers are compared to theoretical values calculated from the travel times computed between grid nodes, which are positioned in the structure, and each receiver. In a second approach, we estimate the slowness vector by using MUSIC algorithm applied to 3-components data. From the slowness vector, we deduce the back-azimuth and the incident angle, which give an estimation of LP source depth in the conduit. This work is part of the Domerapi project funded by French Agence Nationale de la Recherche (https

  1. Locating Supplemental Sources of Revenue to Finance Universities in Nigeria.

    Science.gov (United States)

    Ogunla, Akin L.

    1989-01-01

    Identifies possible sources of supplemental income to finance Nigerian universities, including households and commercial and industrial firms. A consumption tax imposed on certain goods and services would generate needed funds. Also, because firms employ university graduates to earn higher profits, their turnover income should be taxed to support…

  2. Locating sources within a dense sensor array using graph clustering

    Science.gov (United States)

    Gerstoft, P.; Riahi, N.

    2017-12-01

    We develop a model-free technique to identify weak sources within dense sensor arrays using graph clustering. No knowledge about the propagation medium is needed except that signal strengths decay to insignificant levels within a scale that is shorter than the aperture. We then reinterpret the spatial coherence matrix of a wave field as a matrix whose support is a connectivity matrix of a graph with sensors as vertices. In a dense network, well-separated sources induce clusters in this graph. The geographic spread of these clusters can serve to localize the sources. The support of the covariance matrix is estimated from limited-time data using a hypothesis test with a robust phase-only coherence test statistic combined with a physical distance criterion. The latter criterion ensures graph sparsity and thus prevents clusters from forming by chance. We verify the approach and quantify its reliability on a simulated dataset. The method is then applied to data from a dense 5200 element geophone array that blanketed of the city of Long Beach (CA). The analysis exposes a helicopter traversing the array and oil production facilities.

  3. The Effect of Anatomical Location of Lymph Node Metastases on Cancer Specific Survival in Patients with Clear Cell Renal Cell Carcinoma.

    Science.gov (United States)

    Nini, Alessandro; Larcher, Alessandro; Cianflone, Francesco; Trevisani, Francesco; Terrone, Carlo; Volpe, Alessandro; Regis, Federica; Briganti, Alberto; Salonia, Andrea; Montorsi, Francesco; Bertini, Roberto; Capitanio, Umberto

    2018-01-01

    Positive nodal status (pN1) is an independent predictor of survival in renal cell carcinoma (RCC) patients. However, no study to date has tested whether the location of lymph node (LN) metastases does affect oncologic outcomes in a population submitted to radical nephrectomy (RN) and extended lymph node dissection (eLND). To describe nodal disease dissemination in clear cell RCC (ccRCC) patients and to assess the effect of the anatomical sites and the number of nodal areas affected on cancer specific mortality (CSM). The study included 415 patients who underwent RN and eLND, defined as the removal of hilar, side-specific (pre/paraaortic or pre/paracaval) and interaortocaval LNs for ccRCC, at two institutions. Descriptive statistics were used to depict nodal dissemination in pN1 patients, stratified according to nodal site and number of involved areas. Multivariable Cox regression analyses and Kaplan-Meier curves were used to explore the relationship between pN1 disease features and survival outcomes. Median number of removed LN was 14 (IQR 9-19); 23% of patients were pN1. Among patients with one involved nodal site, 54 and 26% of patients were positive only in side-specific and interaortocaval station, respectively. The most frequent nodal site was the interaortocaval and side-specific one, for right and left ccRCC, respectively. Interaortocaval nodal positivity (HR 2.3, CI 95%: 1.3-3.9, p < 0.01) represented an independent predictor of CSM. When ccRCC patient harbour nodal disease, its spreading can occur at any nodal station without involving the others. The presence of interoartocaval positive nodes does affect oncologic outcomes. Lymph node invasion in patients with clear cell renal cell carcinoma is not following a fixed anatomical pattern. An extended lymph node dissection, during treatment for primary kidney tumour, would aid patient risk stratification and multimodality upfront treatment.

  4. Inaccuracy of Location Information as a Consequence of Data Collection Delay and Presence of Misbehaving and Malicious Nodes

    DEFF Research Database (Denmark)

    Madsen, Tatiana Kozlova; Nielsen, Jimmy Jessen; Garcia, Mariano

    2012-01-01

    This paper presents an overview of current research investigations within the WHERE-2 Project with respect to possibilities of usage of geo-location information for protocol and system optimizations. In this work we would like to underline that incorporating the knowledge of nodes’ location in pr...

  5. Application of Emerging Open-source Embedded Systems for Enabling Low-cost Wireless Mini-observatory Nodes in the Coastal Zone

    Science.gov (United States)

    Glazer, B. T.

    2016-02-01

    Here, we describe the development of novel, low-cost, open-source instrumentation to enable wireless data transfer of biogeochemical sensors in the coastal zone. The platform is centered upon the Beaglebone Black single board computer. Process-inquiry in environmental sciences suffers from undersampling; enabling sustained and unattended data collection typically involves expensive instrumentation and infrastructure deployed as cabled observatories with little flexibility in deployment location following initial installation. High cost of commercially-available or custom electronic packages have not only limited the number of sensor node sites that can be targeted by reasonably well-funded academic researchers, but have also entirely prohibited widespread engagement with K-12, public non-profit, and `citizen scientist' STEM audiences. The new platform under development represents a balanced blend of research-grade sensors and low-cost open-source electronics that are easily assembled. Custom, robust, open-source code that remains customizable for specific node configurations can match a specific deployment's measurement needs, depending on the scientific research priorities. We have demonstrated prototype capabilities and versatility through lab testing and field deployments of multiple sensor nodes with multiple sensor inputs, all of which are streaming near-real-time data over wireless RF links to a shore-based base station. On shore, first-pass data processing QA/QC takes place and near-real-time plots are made available on the World Wide Web. Specifically, we have worked closely with an environmental and cultural management and restoration non-profit organization, and middle and high school science classes, engaging their interest in STEM application to local watershed processes. Ultimately, continued successful development of this pilot project can lead to a coastal oceanographic analogue of the popular Weather Underground personal weather station model.

  6. Seismic precursors of vulcanian explosions at Ubinas volcano (Peru) : Statistical analysis and source locations

    Science.gov (United States)

    Métaxian, J.-P.; Macedo, O.; Lengline, O.; Monteiller, V.; Taipe, E.

    2009-04-01

    Ubinas stratovolcano (5672 m), located 60 km east from Arequipa city is historically the most active volcano in Peru. The present eruption began on March 25th 2006. A lava plug has been observed at the bottom of the pit crater situated in the south part of the caldeira. The eruptive activity involves very brought closer exhalations rising a few hundred meters above the crater rim to larger plumes produced by explosions that may reach up to 3 kilometers. The seismic activity is characterized by high rates of long-period (LP) event production accompanying eruptive activity and very long period (VLP) events observed at the same time as vulcanian explosions. The LP and VLP events have a spectral content respectively dominated by frequencies between 2-5 Hz and 0.3-0.9 Hz. The vulcanian explosive activity is characterized by the occurrence of LP swarm preceding most of the VLPs by about 2 hours. In some occasions, the LP swarm merges into tremor about half an hour before the explosion. LPs belonging to the same swarm have similar waveform suggesting a unique source area, which could be the conduit and/or the lava plug surface. The monitoring system includes 4 seismic stations, among which one is equipped with a broadband sensor and 2 tiltmeters. In this work we analyzed a catalogue of data including more than 40000 LP events and 130 VLP events recorded between May 2006 and December 2008. The evolution of the average number of LP events preceding explosions was computed. The variation of the LP rate is clearly diverging from the background rate ~ 0.1 days before explosions. In particular, the most energetic explosions are correlated with the biggest increases of seismicity. However this general behavior is not observed for every single explosion. A direct test is now under study in order to check if the earthquake rate can be used as an alert tool for future explosions. To locate the source of LP events belonging to the swarms, we used a method based on the measurement of

  7. Probabilistic prosumer node modeling for estimating planning parameters in distribution networks with renewable energy sources

    DEFF Research Database (Denmark)

    Millar, Robert John; Ekstrom, Jussi; Lehtonen, Matti

    With the increase in distributed generation, the demand-only nature of many secondary substation nodes in medium voltage networks is becoming a mix of temporally varying consumption and generation with significant stochastic components. Traditional planning, however, has often assumed that the ma...

  8. Gamma ray burst source locations with the Ulysses/Compton/PVO Network

    International Nuclear Information System (INIS)

    Cline, T.L.; Hurley, K.C.; Boer, M.; Sommer, M.; Niel, M.; Fishman, G.J.; Kouveliotou, C.; Meegan, C.A.; Paciesas, W.S.; Wilson, R.B.; Laros, J.G.; Klebesadel, R.W.

    1991-01-01

    The new interplanetary gamma-ray burst network will determine source fields with unprecedented accuracy. The baseline of the Ulysses mission and the locations of Pioneer-Venus Orbiter and of Mars Observer will ensure precision to a few tens of arc seconds. Combined with the event phenomenologies of the Burst and Transient Source Experiment on Compton Observatory, the source locations to be achieved with this network may provide a basic new understanding of the puzzle of gamma ray bursts

  9. Impact source location on composite CNG storage tank using acoustic emission energy based signal mapping method

    Energy Technology Data Exchange (ETDEWEB)

    Han, Byeong Hee; Yoon, Dong Jin; Park, Chun Soo [Korea Research Institute of Standards and Science, Center for Safety Measurement, Daejeon (Korea, Republic of); Lee, Young Shin [Dept. of Mechanical Design Engineering, Chungnam National University, Daejeon (Korea, Republic of)

    2016-10-15

    Acoustic emission (AE) is one of the most powerful techniques for detecting damages and identify damage location during operations. However, in case of the source location technique, there is some limitation in conventional AE technology, because it strongly depends on wave speed in the corresponding structures having heterogeneous composite materials. A compressed natural gas(CNG) pressure vessel is usually made of carbon fiber composite outside of vessel for the purpose of strengthening. In this type of composite material, locating impact damage sources exactly using conventional time arrival method is difficult. To overcome this limitation, this study applied the previously developed Contour D/B map technique to four types of CNG storage tanks to identify the source location of damages caused by external shock. The results of the identification of the source location for different types were compared.

  10. An eikonal-based formulation for traveltime perturbation with respect to the source location

    KAUST Repository

    Alkhalifah, Tariq

    2010-11-01

    Traveltime calculations amount to solving the nonlinear eikonal equation for a given source location. The relationship between the eikonal solution and its perturbations is analyzed with respect to the source location and a partial differential equation is developed that relates the traveltime field for one source location to that for a nearby source. This linear first-order equation in one form depends on lateral changes in velocity and in another form is independent of the velocity field and relies on second-order derivatives of the original traveltime field. For stable finite-difference calculations, this requires the velocity field to be smooth in a sense similar to ray-tracing requirements. Our formulation for traveltime perturbation has several potential applications, such that as traveltime calculation by source-location perturbation, velocity-independent interpolation including datuming, and velocity estimation. Additionally, higher-order expansions provide parameters necessary for Gaussian-beam computations. © 2010 Society of Exploration Geophysicists.

  11. An eikonal-based formulation for traveltime perturbation with respect to the source location

    KAUST Repository

    Alkhalifah, Tariq; Fomel, Sergey

    2010-01-01

    Traveltime calculations amount to solving the nonlinear eikonal equation for a given source location. The relationship between the eikonal solution and its perturbations is analyzed with respect to the source location and a partial differential equation is developed that relates the traveltime field for one source location to that for a nearby source. This linear first-order equation in one form depends on lateral changes in velocity and in another form is independent of the velocity field and relies on second-order derivatives of the original traveltime field. For stable finite-difference calculations, this requires the velocity field to be smooth in a sense similar to ray-tracing requirements. Our formulation for traveltime perturbation has several potential applications, such that as traveltime calculation by source-location perturbation, velocity-independent interpolation including datuming, and velocity estimation. Additionally, higher-order expansions provide parameters necessary for Gaussian-beam computations. © 2010 Society of Exploration Geophysicists.

  12. A New Wave Equation Based Source Location Method with Full-waveform Inversion

    KAUST Repository

    Wu, Zedong

    2017-05-26

    Locating the source of a passively recorded seismic event is still a challenging problem, especially when the velocity is unknown. Many imaging approaches to focus the image do not address the velocity issue and result in images plagued with illumination artifacts. We develop a waveform inversion approach with an additional penalty term in the objective function to reward the focusing of the source image. This penalty term is relaxed early to allow for data fitting, and avoid cycle skipping, using an extended source. At the later stages the focusing of the image dominates the inversion allowing for high resolution source and velocity inversion. We also compute the source location explicitly and numerical tests show that we obtain good estimates of the source locations with this approach.

  13. The effect of location of a convective heat source on displacement ventilation: CFD study

    Energy Technology Data Exchange (ETDEWEB)

    Park, H.J.; Holland, D. [Dunham Associates, Inc., Minneapolis, MN (United States). Advanced Technologies Group

    2001-08-01

    Two-dimensional computational simulations are performed to examine the effect of vertical location of a convective heat source on thermal displacement ventilation systems. In this study, a heat source is modeled with seven different heights from the floor (0.5, 0.75, 1.0, 1.25, 1.5, 1.75, 2.0 m) in a displacement ventilation environment. The flow and temperature fields in thermal displacement ventilation systems vary depending on the location of the heat source. As the heat source rises, the convective heat gain from the heat source to an occupied zone becomes less significant. This effect changes the temperature field and results in the reduction of the cooling load in the occupied zone. The stratification level is also affected by the heat source location at a given flow rate. (author)

  14. High-resolution and super stacking of time-reversal mirrors in locating seismic sources

    KAUST Repository

    Cao, Weiping; Hanafy, Sherif M.; Schuster, Gerard T.; Zhan, Ge; Boonyasiriwat, Chaiwoot

    2011-01-01

    Time reversal mirrors can be used to backpropagate and refocus incident wavefields to their actual source location, with the subsequent benefits of imaging with high-resolution and super-stacking properties. These benefits of time reversal mirrors

  15. Estimation of microwave source location in precipitating electron fluxes according to Viking satellite data

    International Nuclear Information System (INIS)

    Khrushchinskij, A.A.; Ostapenko, A.A.; Gustafsson, G.; Eliasson, L.; Sandal, I.

    1989-01-01

    According to the Viking satellite data on electron fluxes in the 0.1-300 keV energy range, the microburst source location is estimated. On the basis of experimental delays in detected peaks in different energy channels and theoretical calculations of these delays within the dipole field model (L∼ 4-5.5), it is shown that the most probable source location is the equatorial region with the centre, 5-10 0 shifted towards the ionosphere

  16. Acoustic Emission Source Location Using a Distributed Feedback Fiber Laser Rosette

    Directory of Open Access Journals (Sweden)

    Fang Li

    2013-10-01

    Full Text Available This paper proposes an approach for acoustic emission (AE source localization in a large marble stone using distributed feedback (DFB fiber lasers. The aim of this study is to detect damage in structures such as those found in civil applications. The directional sensitivity of DFB fiber laser is investigated by calculating location coefficient using a method of digital signal analysis. In this, autocorrelation is used to extract the location coefficient from the periodic AE signal and wavelet packet energy is calculated to get the location coefficient of a burst AE source. Normalization is processed to eliminate the influence of distance and intensity of AE source. Then a new location algorithm based on the location coefficient is presented and tested to determine the location of AE source using a Delta (Δ DFB fiber laser rosette configuration. The advantage of the proposed algorithm over the traditional methods based on fiber Bragg Grating (FBG include the capability of: having higher strain resolution for AE detection and taking into account two different types of AE source for location.

  17. An efficient closed-form solution for acoustic emission source location in three-dimensional structures

    Directory of Open Access Journals (Sweden)

    Xibing Li

    2014-02-01

    Full Text Available This paper presents an efficient closed-form solution (ECS for acoustic emission(AE source location in three-dimensional structures using time difference of arrival (TDOA measurements from N receivers, N ≥ 6. The nonlinear location equations of TDOA are simplified to linear equations. The unique analytical solution of AE sources for unknown velocity system is obtained by solving the linear equations. The proposed ECS method successfully solved the problems of location errors resulting from measured deviations of velocity as well as the existence and multiplicity of solutions induced by calculations of square roots in existed close-form methods.

  18. A location procedure for sound sources in reactor-technical enclosures

    International Nuclear Information System (INIS)

    Hamann, D.

    1982-07-01

    A passive method requiring one detector only has been developed for the location of sound emitting faults in nuclear power plant components. It is adapted for use in a frequency range the wavelength of which is of the same order of magnitude as characteristic dimensions of the considered enclosure. The location is performed in the following way: (1) For a fixed detector position the Auto Power Spectral Density (APSD) of the source to be located is measured. (2) For this detector position the APSD is calculated for the potential source locations. For this, the free-field APSD as well as the acoustic normal modes of the enclosure are necessary. (3) The measured APSD is compared with the theoretically obtained APSD's. (4) That APSD is determined which is most similar to the measured APSD, and consequently an information about the unknown source position is got. (author)

  19. A Practical Method of Acoustic Emission Source Location in Anisotropic Composite Laminates

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeong Kon; Kang, Yong Kyu; Kwon, Oh Yang [Inha University, Incheon (Korea, Republic of)

    2003-06-15

    Since the velocity is dependent on the fiber orientation in anisotropic composites, the application of traditional acoustic emission (AE) source location techniques based on the constant velocity to composite structures has been practically impossible. The anisotropy makes the source location procedure complicated and deteriorates the accuracy of the location. In this study, we have divided the region of interest(ROI) into a set of finite elements, taken each element as a virtual source, and calculated the arrival time differences between sensors by using the velocities at every degree from 0 to 90. The calculated and the experimentally measured values of the arrival time difference aye then compared to minimize the location error. The results from two different materials, namely AA6061-T6 and CFRP(uni-directional; UD, [0]{sub 32}4 ) laminate confirmed the practical usefulness of the proposed method

  20. Bayesian statistics applied to the location of the source of explosions at Stromboli Volcano, Italy

    Science.gov (United States)

    Saccorotti, G.; Chouet, B.; Martini, M.; Scarpa, R.

    1998-01-01

    We present a method for determining the location and spatial extent of the source of explosions at Stromboli Volcano, Italy, based on a Bayesian inversion of the slowness vector derived from frequency-slowness analyses of array data. The method searches for source locations that minimize the error between the expected and observed slowness vectors. For a given set of model parameters, the conditional probability density function of slowness vectors is approximated by a Gaussian distribution of expected errors. The method is tested with synthetics using a five-layer velocity model derived for the north flank of Stromboli and a smoothed velocity model derived from a power-law approximation of the layered structure. Application to data from Stromboli allows for a detailed examination of uncertainties in source location due to experimental errors and incomplete knowledge of the Earth model. Although the solutions are not constrained in the radial direction, excellent resolution is achieved in both transverse and depth directions. Under the assumption that the horizontal extent of the source does not exceed the crater dimension, the 90% confidence region in the estimate of the explosive source location corresponds to a small volume extending from a depth of about 100 m to a maximum depth of about 300 m beneath the active vents, with a maximum likelihood source region located in the 120- to 180-m-depth interval.

  1. Planar location of the simulative acoustic source based on fiber optic sensor array

    Science.gov (United States)

    Liang, Yi-Jun; Liu, Jun-feng; Zhang, Qiao-ping; Mu, Lin-lin

    2010-06-01

    A fiber optic sensor array which is structured by four Sagnac fiber optic sensors is proposed to detect and locate a simulative source of acoustic emission (AE). The sensing loops of Sagnac interferometer (SI) are regarded as point sensors as their small size. Based on the derived output light intensity expression of SI, the optimum work condition of the Sagnac fiber optic sensor is discussed through the simulation of MATLAB. Four sensors are respectively placed on a steel plate to structure the sensor array and the location algorithms are expatiated. When an impact is generated by an artificial AE source at any position of the plate, the AE signal will be detected by four sensors at different times. With the help of a single chip microcomputer (SCM) which can calculate the position of the AE source and display it on LED, we have implemented an intelligent detection and location.

  2. Locating the Source of Atmospheric Contamination Based on Data From the Kori Field Tracer Experiment

    Directory of Open Access Journals (Sweden)

    Piotr Kopka

    2015-01-01

    Full Text Available Accidental releases of hazardous material into the atmosphere pose high risks to human health and the environment. Thus it would be valuable to develop an emergency reaction system which can recognize the probable location of the source based only on concentrations of the released substance as reported by a network of sensors. We apply a methodology combining Bayesian inference with Sequential Monte Carlo (SMC methods to the problem of locating the source of an atmospheric contaminant. The input data for this algorithm are the concentrations of a given substance gathered continuously in time. We employ this algorithm to locating a contamination source using data from a field tracer experiment covering the Kori nuclear site and conducted in May 2001. We use the second-order Closure Integrated PUFF Model (SCIPUFF of atmospheric dispersion as the forward model to predict concentrations at the sensors' locations. We demonstrate that the source of continuous contamination may be successfully located even in the very complicated, hilly terrain surrounding the Kori nuclear site. (original abstract

  3. An FBG acoustic emission source locating system based on PHAT and GA

    Science.gov (United States)

    Shen, Jing-shi; Zeng, Xiao-dong; Li, Wei; Jiang, Ming-shun

    2017-09-01

    Using the acoustic emission locating technology to monitor the health of the structure is important for ensuring the continuous and healthy operation of the complex engineering structures and large mechanical equipment. In this paper, four fiber Bragg grating (FBG) sensors are used to establish the sensor array to locate the acoustic emission source. Firstly, the nonlinear locating equations are established based on the principle of acoustic emission, and the solution of these equations is transformed into an optimization problem. Secondly, time difference extraction algorithm based on the phase transform (PHAT) weighted generalized cross correlation provides the necessary conditions for the accurate localization. Finally, the genetic algorithm (GA) is used to solve the optimization model. In this paper, twenty points are tested in the marble plate surface, and the results show that the absolute locating error is within the range of 10 mm, which proves the accuracy of this locating method.

  4. Methods to identify and locate spent radiation sources; Metodos para la identificacion y localizacion de fuentes radiactivas gastadas

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    The objective of this manual is to provide essential guidance to Member States with nuclear applications involving the use of a wide range of sealed radiation sources on the practical task of physically locating spent radiation sources not properly accounted for. Advice is also provided to render the located source safe on location. Refs, figs, tabs.

  5. An automated multi-scale network-based scheme for detection and location of seismic sources

    Science.gov (United States)

    Poiata, N.; Aden-Antoniow, F.; Satriano, C.; Bernard, P.; Vilotte, J. P.; Obara, K.

    2017-12-01

    We present a recently developed method - BackTrackBB (Poiata et al. 2016) - allowing to image energy radiation from different seismic sources (e.g., earthquakes, LFEs, tremors) in different tectonic environments using continuous seismic records. The method exploits multi-scale frequency-selective coherence in the wave field, recorded by regional seismic networks or local arrays. The detection and location scheme is based on space-time reconstruction of the seismic sources through an imaging function built from the sum of station-pair time-delay likelihood functions, projected onto theoretical 3D time-delay grids. This imaging function is interpreted as the location likelihood of the seismic source. A signal pre-processing step constructs a multi-band statistical representation of the non stationary signal, i.e. time series, by means of higher-order statistics or energy envelope characteristic functions. Such signal-processing is designed to detect in time signal transients - of different scales and a priori unknown predominant frequency - potentially associated with a variety of sources (e.g., earthquakes, LFE, tremors), and to improve the performance and the robustness of the detection-and-location location step. The initial detection-location, based on a single phase analysis with the P- or S-phase only, can then be improved recursively in a station selection scheme. This scheme - exploiting the 3-component records - makes use of P- and S-phase characteristic functions, extracted after a polarization analysis of the event waveforms, and combines the single phase imaging functions with the S-P differential imaging functions. The performance of the method is demonstrated here in different tectonic environments: (1) analysis of the one year long precursory phase of 2014 Iquique earthquake in Chile; (2) detection and location of tectonic tremor sources and low-frequency earthquakes during the multiple episodes of tectonic tremor activity in southwestern Japan.

  6. Locating a compact odor source using a four-channel insect electroantennogram sensor

    Energy Technology Data Exchange (ETDEWEB)

    Myrick, A J; Baker, T C [Chemical Ecology Laboratory, Department of Entomology, Pennsylvania State University, University Park, PA 16802 (United States)

    2011-03-15

    Here we demonstrate the feasibility of using an array of live insects to detect concentrated packets of odor and infer the location of an odor source ({approx}15 m away) using a backward Lagrangian dispersion model based on the Langevin equation. Bayesian inference allows uncertainty to be quantified, which is useful for robotic planning. The electroantennogram (EAG) is the biopotential developed between the tissue at the tip of an insect antenna and its base, which is due to the massed response of the olfactory receptor neurons to an odor stimulus. The EAG signal can carry tens of bits per second of information with a rise time as short as 12 ms (K A Justice 2005 J. Neurophiol. 93 2233-9). Here, instrumentation including a GPS with a digital compass and an ultrasonic 2D anemometer has been integrated with an EAG odor detection scheme, allowing the location of an odor source to be estimated by collecting data at several downwind locations. Bayesian inference in conjunction with a Lagrangian dispersion model, taking into account detection errors, has been implemented resulting in an estimate of the odor source location within 0.2 m of the actual location.

  7. Locating a compact odor source using a four-channel insect electroantennogram sensor

    International Nuclear Information System (INIS)

    Myrick, A J; Baker, T C

    2011-01-01

    Here we demonstrate the feasibility of using an array of live insects to detect concentrated packets of odor and infer the location of an odor source (∼15 m away) using a backward Lagrangian dispersion model based on the Langevin equation. Bayesian inference allows uncertainty to be quantified, which is useful for robotic planning. The electroantennogram (EAG) is the biopotential developed between the tissue at the tip of an insect antenna and its base, which is due to the massed response of the olfactory receptor neurons to an odor stimulus. The EAG signal can carry tens of bits per second of information with a rise time as short as 12 ms (K A Justice 2005 J. Neurophiol. 93 2233-9). Here, instrumentation including a GPS with a digital compass and an ultrasonic 2D anemometer has been integrated with an EAG odor detection scheme, allowing the location of an odor source to be estimated by collecting data at several downwind locations. Bayesian inference in conjunction with a Lagrangian dispersion model, taking into account detection errors, has been implemented resulting in an estimate of the odor source location within 0.2 m of the actual location.

  8. A hybrid algorithm for stochastic single-source capacitated facility location problem with service level requirements

    Directory of Open Access Journals (Sweden)

    Hosseinali Salemi

    2016-04-01

    Full Text Available Facility location models are observed in many diverse areas such as communication networks, transportation, and distribution systems planning. They play significant role in supply chain and operations management and are one of the main well-known topics in strategic agenda of contemporary manufacturing and service companies accompanied by long-lasting effects. We define a new approach for solving stochastic single source capacitated facility location problem (SSSCFLP. Customers with stochastic demand are assigned to set of capacitated facilities that are selected to serve them. It is demonstrated that problem can be transformed to deterministic Single Source Capacitated Facility Location Problem (SSCFLP for Poisson demand distribution. A hybrid algorithm which combines Lagrangian heuristic with adjusted mixture of Ant colony and Genetic optimization is proposed to find lower and upper bounds for this problem. Computational results of various instances with distinct properties indicate that proposed solving approach is efficient.

  9. Chemometric Analysis for Pollution Source Assessment of Harbour Sediments in Arctic Locations

    DEFF Research Database (Denmark)

    Pedersen, Kristine B.; Lejon, Tore; Jensen, Pernille Erland

    2015-01-01

    Pollution levels, pollutant distribution and potential source assessments based on multivariate analysis (chemometrics) were made for harbour sediments from two Arctic locations; Hammerfest in Norway and Sisimiut in Greenland. High levels of heavy metals were detected in addition to organic...... pollutants. Preliminary assessments based on principal component analysis (PCA) revealed different sources and pollutant distribution in the sediments of the two harbours. Tributyltin (TBT) was, however, found to originate from point source(s), and the highest concentrations of TBT in both harbours were...... indicated relation primarily to German, Russian and American mixtures in Hammerfest; and American, Russian and Japanese mixtures in Sisimiut. PCA was shown to be an important tool for identifying pollutant sources and differences in pollutant composition in relation to sediment characteristics....

  10. Characteristics of Love and Rayleigh waves in ambient noise: wavetype ratio, source location and seasonal behavior

    Science.gov (United States)

    Juretzek, C.; Perleth, M.; Hadziioannou, C.

    2015-12-01

    Ambient seismic noise has become an important source of signal for tomography and monitoring purposes. Better understanding of the noise field characteristics is crucial to further improve noise applications. Our knowledge about the common and different origins of Love and Rayleigh waves in the microseism bands is still limited. This applies in particular to constraints on source locations and source mechanisms of Love waves. Here, 3-component beamforming is used to distinguish between the differently polarized wave types present in the noise field recorded at several arrays across Europe. The focus lies on frequencies around the primary and secondary microseismic bands. We compare characteristics of Love and Rayleigh wave noise, such as source directions and frequency content. Further, Love to Rayleigh wave ratios are measured at each array, and a dependence on direction is observed. We constrain the corresponding source regions of both wave types by backprojection. By using a full year of data in 2013, we are able to track the seasonal changes in our observations of Love-to-Rayleigh ratio and source locations.

  11. Identification of sources of aerosol particles in three locations in eastern Botswana

    Science.gov (United States)

    Chimidza, S.; Moloi, K.

    2000-07-01

    Airborne particles have been collected using a dichotomous virtual impactor at three different locations in the eastern part of Botswana: Serowe, Selibe-Phikwe, and Francistown. The particles were separated into two fractions (fine and coarse). Sampling at the three locations was done consecutively during the months of July and August, which are usually dry and stable. The sampling time for each sample was 12 hours during the day. For elemental composition, energy-dispersive x-ray fluorescence technique was used. Correlations and principal component analysis with varimax rotation were used to identify major sources of aerosol particles. In all the three places, soil was found to be the main source of aerosol particles. A copper-nickel mine and smelter at Selibe-Phikwe was found to be not only a source of copper and nickel particles in Selibe-Phikwe but also a source of these particles in far places like Serowe. In Selibe-Phikwe and Francistown, car exhaust was found to be the major source of fine particles of lead and bromine.

  12. The use of permit markets for incorporating source location. The case of acid rain in Europe

    International Nuclear Information System (INIS)

    Steiner, U.; Tinggaard Svendsen, G.

    1997-01-01

    The paper shows that cost-effective involvement of the source location involves utmost difficulty in practice. Based on the RAINS model, it is recommended that source location should be ignored in a European market for SO 2 , as is the case in the US Acid Rain Program. The RAINS-model predicts a cost-saving of 37 percent but an average loss of 2 percent in ecological protection. To overcome this reduction in protection, we recommend that some of the large cost-savings should be reallocated in further overall reduction and that the countries suffering the most from introducing the permit-market should be compensated by receiving extra permits in the initial distribution. (au)

  13. Acoustic emission non-destructive testing of structures using source location techniques.

    Energy Technology Data Exchange (ETDEWEB)

    Beattie, Alan G.

    2013-09-01

    The technology of acoustic emission (AE) testing has been advanced and used at Sandia for the past 40 years. AE has been used on structures including pressure vessels, fire bottles, wind turbines, gas wells, nuclear weapons, and solar collectors. This monograph begins with background topics in acoustics and instrumentation and then focuses on current acoustic emission technology. It covers the overall design and system setups for a test, with a wind turbine blade as the object. Test analysis is discussed with an emphasis on source location. Three test examples are presented, two on experimental wind turbine blades and one on aircraft fire extinguisher bottles. Finally, the code for a FORTRAN source location program is given as an example of a working analysis program. Throughout the document, the stress is on actual testing of real structures, not on laboratory experiments.

  14. Precise tremor source locations and amplitude variations along the lower-crustal central San Andreas Fault

    Science.gov (United States)

    Shelly, David R.; Hardebeck, Jeanne L.

    2010-01-01

    We precisely locate 88 tremor families along the central San Andreas Fault using a 3D velocity model and numerous P and S wave arrival times estimated from seismogram stacks of up to 400 events per tremor family. Maximum tremor amplitudes vary along the fault by at least a factor of 7, with by far the strongest sources along a 25 km section of the fault southeast of Parkfield. We also identify many weaker tremor families, which have largely escaped prior detection. Together, these sources extend 150 km along the fault, beneath creeping, transitional, and locked sections of the upper crustal fault. Depths are mostly between 18 and 28 km, in the lower crust. Epicenters are concentrated within 3 km of the surface trace, implying a nearly vertical fault. A prominent gap in detectible activity is located directly beneath the region of maximum slip in the 2004 magnitude 6.0 Parkfield earthquake.

  15. Coded aperture detector for high precision gamma-ray burst source locations

    International Nuclear Information System (INIS)

    Helmken, H.; Gorenstein, P.

    1977-01-01

    Coded aperture collimators in conjunction with position-sensitive detectors are very useful in the study of transient phenomenon because they combine broad field of view, high sensitivity, and an ability for precise source locations. Since the preceeding conference, a series of computer simulations of various detector designs have been carried out with the aid of a CDC 6400. Particular emphasis was placed on the development of a unit consisting of a one-dimensional random or periodic collimator in conjunction with a two-dimensional position-sensitive Xenon proportional counter. A configuration involving four of these units has been incorporated into the preliminary design study of the Transient Explorer (ATREX) satellite and are applicable to any SAS or HEAO type satellite mission. Results of this study, including detector response, fields of view, and source location precision, will be presented

  16. Travel-time source-specific station correction improves location accuracy

    Science.gov (United States)

    Giuntini, Alessandra; Materni, Valerio; Chiappini, Stefano; Carluccio, Roberto; Console, Rodolfo; Chiappini, Massimo

    2013-04-01

    Accurate earthquake locations are crucial for investigating seismogenic processes, as well as for applications like verifying compliance to the Comprehensive Test Ban Treaty (CTBT). Earthquake location accuracy is related to the degree of knowledge about the 3-D structure of seismic wave velocity in the Earth. It is well known that modeling errors of calculated travel times may have the effect of shifting the computed epicenters far from the real locations by a distance even larger than the size of the statistical error ellipses, regardless of the accuracy in picking seismic phase arrivals. The consequences of large mislocations of seismic events in the context of the CTBT verification is particularly critical in order to trigger a possible On Site Inspection (OSI). In fact, the Treaty establishes that an OSI area cannot be larger than 1000 km2, and its larger linear dimension cannot be larger than 50 km. Moreover, depth accuracy is crucial for the application of the depth event screening criterion. In the present study, we develop a method of source-specific travel times corrections based on a set of well located events recorded by dense national seismic networks in seismically active regions. The applications concern seismic sequences recorded in Japan, Iran and Italy. We show that mislocations of the order of 10-20 km affecting the epicenters, as well as larger mislocations in hypocentral depths, calculated from a global seismic network and using the standard IASPEI91 travel times can be effectively removed by applying source-specific station corrections.

  17. High-resolution and super stacking of time-reversal mirrors in locating seismic sources

    KAUST Repository

    Cao, Weiping

    2011-07-08

    Time reversal mirrors can be used to backpropagate and refocus incident wavefields to their actual source location, with the subsequent benefits of imaging with high-resolution and super-stacking properties. These benefits of time reversal mirrors have been previously verified with computer simulations and laboratory experiments but not with exploration-scale seismic data. We now demonstrate the high-resolution and the super-stacking properties in locating seismic sources with field seismic data that include multiple scattering. Tests on both synthetic data and field data show that a time reversal mirror has the potential to exceed the Rayleigh resolution limit by factors of 4 or more. Results also show that a time reversal mirror has a significant resilience to strong Gaussian noise and that accurate imaging of source locations from passive seismic data can be accomplished with traces having signal-to-noise ratios as low as 0.001. Synthetic tests also demonstrate that time reversal mirrors can sometimes enhance the signal by a factor proportional to the square root of the product of the number of traces, denoted as N and the number of events in the traces. This enhancement property is denoted as super-stacking and greatly exceeds the classical signal-to-noise enhancement factor of. High-resolution and super-stacking are properties also enjoyed by seismic interferometry and reverse-time migration with the exact velocity model. © 2011 European Association of Geoscientists & Engineers.

  18. Measurement of acoustic characteristics of Japanese Buddhist temples in relation to sound source location and direction.

    Science.gov (United States)

    Soeta, Yoshiharu; Shimokura, Ryota; Kim, Yong Hee; Ohsawa, Tomohiro; Ito, Ken

    2013-05-01

    Although temples are important buildings in the Buddhist community, the acoustic quality has not been examined in detail. Buddhist monks change the location and direction according to the ceremony, and associated acoustical changes have not yet been examined scientifically. To discuss the desired acoustics of temples, it is necessary to know the acoustic characteristics appropriate for each phase of a ceremony. In this study, acoustic measurements were taken at various source locations and directions in Japanese temples. A directional loudspeaker was used as the source to provide vocal acoustic fields, and impulse responses were measured and analyzed. The speech transmission index was higher and the interaural cross-correlation coefficient was lower for the sound source directed toward the side wall than that directed toward the altar. This suggests that the change in direction improves speech intelligibility, and the asymmetric property of direct sound and complex reflections from the altar and side wall increases the apparent source width. The large and coupled-like structure of the altar of a Buddhist temple may have reinforced the reverberation components and the table in the altar, which is called the "syumidan," may have decreased binaural coherence.

  19. Transport of perfluoroalkyl substances (PFAS) from an arctic glacier to downstream locations: implications for sources.

    Science.gov (United States)

    Kwok, Karen Y; Yamazaki, Eriko; Yamashita, Nobuyoshi; Taniyasu, Sachi; Murphy, Margaret B; Horii, Yuichi; Petrick, Gert; Kallerborn, Roland; Kannan, Kurunthachalam; Murano, Kentaro; Lam, Paul K S

    2013-03-01

    Perfluoroalkyl substances (PFAS) have been globally detected in various environmental matrices, yet their fate and transport to the Arctic is still unclear, especially for the European Arctic. In this study, concentrations of 17 PFAS were quantified in two ice cores (n=26), surface snow (n=9) and surface water samples (n=14) collected along a spatial gradient in Svalbard, Norway. Concentrations of selected ions (Na(+), SO4(2-), etc.) were also determined for tracing the origins and sources of PFAS. Perfluorobutanoate (PFBA), perfluorooctanoate (PFOA) and perfluorononanoate (PFNA) were the dominant compounds found in ice core samples. Taking PFOA, PFNA and perfluorooctane-sulfonate (PFOS) as examples, higher concentrations were detected in the middle layers of the ice cores representing the period of 1997-2000. Lower concentrations of C8-C12 perfluorocarboxylates (PFCAs) were detected in comparison with concentrations measured previously in an ice core from the Canadian Arctic, indicating that contamination levels in the European Arctic are lower. Average PFAS concentrations were found to be lower in surface snow and melted glacier water samples, while increased concentrations were observed in river water downstream near the coastal area. Perfluorohexanesulfonate (PFHxS) was detected in the downstream locations, but not in the glacier, suggesting existence of local sources of this compound. Long-range atmospheric transport of PFAS was the major deposition pathway for the glaciers, while local sources (e.g., skiing activities) were identified in the downstream locations. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Joint Source Location and Focal Mechanism Inversion: efficiency, accuracy and applications

    Science.gov (United States)

    Liang, C.; Yu, Y.

    2017-12-01

    The analysis of induced seismicity has become a common practice to evaluate the results of hydraulic fracturing treatment. Liang et al (2016) proposed a joint Source Scanning Algorithms (jSSA for short) to obtain microseismic events and focal mechanisms simultaneously. The jSSA is superior over traditional SSA in many aspects, but the computation cost is too significant to be applied in real time monitoring. In this study, we have developed several scanning schemas to reduce computation time. A multi-stage scanning schema is proved to be able to improve the efficiency significantly while also retain its accuracy. A series of tests have been carried out by using both real field data and synthetic data to evaluate the accuracy of the method and its dependence on noise level, source depths, focal mechanisms and other factors. The surface-based arrays have better constraints on horizontal location errors (0.5). For sources with varying rakes, dips, strikes and depths, the errors are mostly controlled by the partition of positive and negative polarities in different quadrants. More evenly partitioned polarities in different quadrants yield better results in both locations and focal mechanisms. Nevertheless, even with bad resolutions for some FMs, the optimized jSSA method can still improve location accuracies significantly. Based on much more densely distributed events and focal mechanisms, a gridded stress inversion is conducted to get a evenly distributed stress field. The full potential of the jSSA has yet to be explored in different directions, especially in earthquake seismology as seismic array becoming incleasingly dense.

  1. Neural network AE source location apart from structure size and material

    Czech Academy of Sciences Publication Activity Database

    Chlada, Milan; Převorovský, Zdeněk; Blaháček, Michal

    2010-01-01

    Roč. 28, - (2010), s. 99-107 ISSN 0730-0050. [European Conference on Acoustic Emission Testing 2010 /29./. Vídeň, 08.09.2010-10.09.2010] R&D Projects: GA ČR(CZ) GAP104/10/1430; GA MPO(CZ) FR-TI1/274 Institutional research plan: CEZ:AV0Z20760514 Keywords : AE source location * artificial neural network * arrival time profiles Subject RIV: BI - Acoustics http://www.ndt.net/search/abstract.php3?AbsID=10828

  2. An improved cut-and-solve algorithm for the single-source capacitated facility location problem

    DEFF Research Database (Denmark)

    Gadegaard, Sune Lauth; Klose, Andreas; Nielsen, Lars Relund

    2018-01-01

    In this paper, we present an improved cut-and-solve algorithm for the single-source capacitated facility location problem. The algorithm consists of three phases. The first phase strengthens the integer program by a cutting plane algorithm to obtain a tight lower bound. The second phase uses a two......-level local branching heuristic to find an upper bound, and if optimality has not yet been established, the third phase uses the cut-and-solve framework to close the optimality gap. Extensive computational results are reported, showing that the proposed algorithm runs 10–80 times faster on average compared...

  3. Locating and Quantifying Broadband Fan Sources Using In-Duct Microphones

    Science.gov (United States)

    Dougherty, Robert P.; Walker, Bruce E.; Sutliff, Daniel L.

    2010-01-01

    In-duct beamforming techniques have been developed for locating broadband noise sources on a low-speed fan and quantifying the acoustic power in the inlet and aft fan ducts. The NASA Glenn Research Center's Advanced Noise Control Fan was used as a test bed. Several of the blades were modified to provide a broadband source to evaluate the efficacy of the in-duct beamforming technique. Phased arrays consisting of rings and line arrays of microphones were employed. For the imaging, the data were mathematically resampled in the frame of reference of the rotating fan. For both the imaging and power measurement steps, array steering vectors were computed using annular duct modal expansions, selected subsets of the cross spectral matrix elements were used, and the DAMAS and CLEAN-SC deconvolution algorithms were applied.

  4. Affective attitudes to face images associated with intracerebral EEG source location before face viewing.

    Science.gov (United States)

    Pizzagalli, D; Koenig, T; Regard, M; Lehmann, D

    1999-01-01

    We investigated whether different, personality-related affective attitudes are associated with different brain electric field (EEG) sources before any emotional challenge (stimulus exposure). A 27-channel EEG was recorded in 15 subjects during eyes-closed resting. After recording, subjects rated 32 images of human faces for affective appeal. The subjects in the first (i.e., most negative) and fourth (i.e., most positive) quartile of general affective attitude were further analyzed. The EEG data (mean=25+/-4. 8 s/subject) were subjected to frequency-domain model dipole source analysis (FFT-Dipole-Approximation), resulting in 3-dimensional intracerebral source locations and strengths for the delta-theta, alpha, and beta EEG frequency band, and for the full range (1.5-30 Hz) band. Subjects with negative attitude (compared to those with positive attitude) showed the following source locations: more inferior for all frequency bands, more anterior for the delta-theta band, more posterior and more right for the alpha, beta and 1.5-30 Hz bands. One year later, the subjects were asked to rate the face images again. The rating scores for the same face images were highly correlated for all subjects, and original and retest affective mean attitude was highly correlated across subjects. The present results show that subjects with different affective attitudes to face images had different active, cerebral, neural populations in a task-free condition prior to viewing the images. We conclude that the brain functional state which implements affective attitude towards face images as a personality feature exists without elicitors, as a continuously present, dynamic feature of brain functioning. Copyright 1999 Elsevier Science B.V.

  5. Reconstruction of source location in a network of gravitational wave interferometric detectors

    International Nuclear Information System (INIS)

    Cavalier, Fabien; Barsuglia, Matteo; Bizouard, Marie-Anne; Brisson, Violette; Clapson, Andre-Claude; Davier, Michel; Hello, Patrice; Kreckelbergh, Stephane; Leroy, Nicolas; Varvella, Monica

    2006-01-01

    This paper deals with the reconstruction of the direction of a gravitational wave source using the detection made by a network of interferometric detectors, mainly the LIGO and Virgo detectors. We suppose that an event has been seen in coincidence using a filter applied on the three detector data streams. Using the arrival time (and its associated error) of the gravitational signal in each detector, the direction of the source in the sky is computed using a χ 2 minimization technique. For reasonably large signals (SNR>4.5 in all detectors), the mean angular error between the real location and the reconstructed one is about 1 deg. . We also investigate the effect of the network geometry assuming the same angular response for all interferometric detectors. It appears that the reconstruction quality is not uniform over the sky and is degraded when the source approaches the plane defined by the three detectors. Adding at least one other detector to the LIGO-Virgo network reduces the blind regions and in the case of 6 detectors, a precision less than 1 deg. on the source direction can be reached for 99% of the sky

  6. Node cookbook

    CERN Document Server

    Clements, David Mark

    2014-01-01

    In Node Cookbook Second Edition, each chapter focuses on a different aspect of working with Node. Following a Cookbook structure, the recipes are written in an easy-to-understand language. Readers will find it easier to grasp even the complex recipes which are backed by lots of illustrations, tips, and hints.If you have some knowledge of JavaScript and want to build fast, efficient, scalable client-server solutions, then Node Cookbook Second Edition is for you. Knowledge of Node will be an advantage but is not required. Experienced users of Node will be able to improve their skills.

  7. Acoustic emission source location in plates using wavelet analysis and cross time frequency spectrum.

    Science.gov (United States)

    Mostafapour, A; Davoodi, S; Ghareaghaji, M

    2014-12-01

    In this study, the theories of wavelet transform and cross-time frequency spectrum (CTFS) are used to locate AE source with frequency-varying wave velocity in plate-type structures. A rectangular array of four sensors is installed on the plate. When an impact is generated by an artificial AE source such as Hsu-Nielsen method of pencil lead breaking (PLB) at any position of the plate, the AE signals will be detected by four sensors at different times. By wavelet packet decomposition, a packet of signals with frequency range of 0.125-0.25MHz is selected. The CTFS is calculated by the short-time Fourier transform of the cross-correlation between considered packets captured by AE sensors. The time delay is calculated when the CTFS reaches the maximum value and the corresponding frequency is extracted per this maximum value. The resulting frequency is used to calculate the group velocity of wave velocity in combination with dispersive curve. The resulted locating error shows the high precision of proposed algorithm. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Solving seismological problems using SGRAPH program: I-source parameters and hypocentral location

    International Nuclear Information System (INIS)

    Abdelwahed, Mohamed F.

    2012-01-01

    SGRAPH program is considered one of the seismological programs that maintain seismic data. SGRAPH is considered unique for being able to read a wide range of data formats and manipulate complementary tools in different seismological subjects in a stand-alone Windows-based application. SGRAPH efficiently performs the basic waveform analysis and solves advanced seismological problems. The graphical user interface (GUI) utilities and the Windows facilities such as, dialog boxes, menus, and toolbars simplified the user interaction with data. SGRAPH supported the common data formats like, SAC, SEED, GSE, ASCII, and Nanometrics Y-format, and others. It provides the facilities to solve many seismological problems with the built-in inversion and modeling tools. In this paper, I discuss some of the inversion tools built-in SGRAPH related to source parameters and hypocentral location estimation. Firstly, a description of the SGRAPH program is given discussing some of its features. Secondly, the inversion tools are applied to some selected events of the Dahshour earthquakes as an example of estimating the spectral and source parameters of local earthquakes. In addition, the hypocentral location of these events are estimated using the Hypoinverse 2000 program operated by SGRAPH.

  9. Investigation of source location determination from Magsat magnetic anomalies: The Euler method approach

    Science.gov (United States)

    Ravat, Dhananjay

    1996-01-01

    The applicability of the Euler method of source location determination was investigated on several model situations pertinent to satellite-data scale situations as well as Magsat data of Europe. Our investigations enabled us to understand the end-member cases for which the Euler method will work with the present satellite magnetic data and also the cases for which the assumptions implicit in the Euler method will not be met by the present satellite magnetic data. These results have been presented in one invited lecture at the Indo-US workshop on Geomagnetism in Studies of the Earth's Interior in August 1994 in Pune, India, and at one presentation at the 21st General Assembly of the IUGG in July 1995 in Boulder, CO. A new method, called Anomaly Attenuation Rate (AAR) Method (based on the Euler method), was developed during this study. This method is scale-independent and is appropriate to locate centroids of semi-compact three dimensional sources of gravity and magnetic anomalies. The method was presented during 1996 Spring AGU meeting and a manuscript describing this method is being prepared for its submission to a high-ranking journal. The grant has resulted in 3 papers and presentations at national and international meetings and one manuscript of a paper (to be submitted shortly to a reputable journal).

  10. Influence of sound source location on the behavior and physiology of the precedence effect in cats.

    Science.gov (United States)

    Dent, Micheal L; Tollin, Daniel J; Yin, Tom C T

    2009-08-01

    Psychophysical experiments on the precedence effect (PE) in cats have shown that they localize pairs of auditory stimuli presented from different locations in space based on the spatial position of the stimuli and the interstimulus delay (ISD) between the stimuli in a manner similar to humans. Cats exhibit localization dominance for pairs of transient stimuli with |ISDs| from approximately 0.4 to 10 ms, summing localization for |ISDs| 10 ms, which is the approximate echo threshold. The neural correlates to the PE have been described in both anesthetized and unanesthetized animals at many levels from auditory nerve to cortex. Single-unit recordings from the inferior colliculus (IC) and auditory cortex of cats demonstrate that neurons respond to both lead and lag sounds at ISDs above behavioral echo thresholds, but the response to the lag is reduced at shorter ISDs, consistent with localization dominance. Here the influence of the relative locations of the leading and lagging sources on the PE was measured behaviorally in a psychophysical task and physiologically in the IC of awake behaving cats. At all configurations of lead-lag stimulus locations, the cats behaviorally exhibited summing localization, localization dominance, and breakdown of fusion. Recordings from the IC of awake behaving cats show neural responses paralleling behavioral measurements. Both behavioral and physiological results suggest systematically shorter echo thresholds when stimuli are further apart in space.

  11. Apparatus and method for locating and quantifying or directing a source of ionizing radiation

    International Nuclear Information System (INIS)

    Rogers, W.L.; Wainstock, M.A.

    1976-01-01

    An apparatus and method for locating or directing a source of ionizing radiation such as X-rays, gamma rays, alpha particles, beta particles, etc. are described. The preferred embodiment detects and locates abnormalities of the body such as ocular melanomas by detecting the emission of radiation from a melanoma which has absorbed a radioactive medium. The apparatus includes an ultrasound probe which emits ultrasonic waves along a first axis and detects a returned portion of the waves. The ultrasound probe is associated with a display which displays the returned portion of the waves in the time domain so that suspected abnormalities can be located. The ultrasound probe is used to guide a directional probe for detecting and quantifying ionizing radiation which is equipped with a focusing collimator having a focal point along a second axis. The two probes are supported so that the first and second axes converge at the focal point of the collimator. A range marker is associated with the ultrasonic detector which indicates the point of convergence of the axes on the ultrasonic display permitting guidance of the radiation detecting probe to the suspected abnormality

  12. Consumption of added sugars among US children and adults by food purchase location and food source.

    Science.gov (United States)

    Drewnowski, Adam; Rehm, Colin D

    2014-09-01

    The proposed changes to the Nutrition Facts Label by the US Food and Drug Administration will include information on added sugars for the first time. The objective was to evaluate the sources of added sugars in the diets of a representative sample of US children and adults by food purchase location and food source (eg, food group). This cross-sectional study among 31,035 children, adolescents, and adults aged ≥6 y from the 2003-2004, 2005-2006, 2007-2008, and 2009-2010 NHANES used data from a 24-h dietary recall to evaluate consumption of added sugars. Food locations of origin were identified as stores (supermarket or grocery store), quick-service restaurants/pizza (QSRs), full-service restaurants (FSRs), schools, and others (eg, vending machines or gifts). Added sugars consumption by food purchase location was evaluated by age, family income-to-poverty ratio, and race-ethnicity. Food group sources of added sugars were identified by using the National Cancer Institute food categories. Added sugars accounted for ∼14.1% of total dietary energy. Between 65% and 76% of added sugars came from stores, 6% and 12% from QSRs, and 4% and 6% from FSRs, depending on age. Older adults (aged ≥51 y) obtained a significantly greater proportion of added sugars from stores than did younger adults. Lower-income adults obtained a significantly greater proportion of added sugars from stores than did higher-income adults. Intake of added sugars did not vary by family income among children/adolescents. Soda and energy and sports drinks were the largest food group sources of added sugars (34.4%), followed by grain desserts (12.7%), fruit drinks (8.0%), candy (6.7%), and dairy desserts (5.6%). Most added sugars came from foods obtained from stores. The proposed changes to the Nutrition Facts Label should capture the bulk of added sugars in the US food supply, which suggests that the recommended changes have the potential to reduce added sugars consumption. © 2014 American Society

  13. Effect of Ion Flux (Dose Rate) in Source-Drain Extension Ion Implantation for 10-nm Node FinFET and Beyond on 300/450mm Platforms

    Science.gov (United States)

    Shen, Ming-Yi

    The improvement of wafer equipment productivity has been a continuous effort of the semiconductor industry. Higher productivity implies lower product price, which economically drives more demand from the market. This is desired by the semiconductor manufacturing industry. By raising the ion beam current of the ion implanter for 300/450mm platforms, it is possible to increase the throughput of the ion implanter. The resulting dose rate can be comparable to the performance of conventional ion implanters or higher, depending on beam current and beam size. Thus, effects caused by higher dose rate must be investigated further. One of the major applications of ion implantation (I/I) is source-drain extension (SDE) I/I for the silicon FinFET device. This study investigated the dose rate effects on the material properties and device performance of the 10-nm node silicon FinFET. In order to gain better understanding of the dose rate effects, the dose rate study is based on Synopsys Technology CAD (TCAD) process and device simulations that are calibrated and validated using available structural silicon fin samples. We have successfully shown that the kinetic monte carlo (KMC) I/I simulation can precisely model both the silicon amorphization and the arsenic distribution in the fin by comparing the KMC simulation results with TEM images. The results of the KMC I/I simulation show that at high dose rate more activated arsenic dopants were in the source-drain extension (SDE) region. This finding matches with the increased silicon amorphization caused by the high dose-rate I/I, given that the arsenic atoms could be more easily activated by the solid phase epitaxial regrowth process. This increased silicon amorphization led to not only higher arsenic activation near the spacer edge, but also less arsenic atoms straggling into the channel. Hence, it is possible to improve the throughput of the ion implanter when the dopants are implanted at high dose rate if the same doping level

  14. The January 2014 Northern Cuba Earthquake Sequence - Unusual Location and Unexpected Source Mechanism Variability

    Science.gov (United States)

    Braunmiller, J.; Thompson, G.; McNutt, S. R.

    2017-12-01

    On 9 January 2014, a magnitude Mw=5.1 earthquake occurred along the Bahamas-Cuba suture at the northern coast of Cuba revealing a surprising seismic hazard source for both Cuba and southern Florida where it was widely felt. Due to its location, the event and its aftershocks (M>3.5) were recorded only at far distances (300+ km) resulting in high-detection thresholds, low location accuracy, and limited source parameter resolution. We use three-component regional seismic data to study the sequence. High-pass filtered seismograms at the closest site in southern Florida are similar in character suggesting a relatively tight event cluster and revealing additional, smaller aftershocks not included in the ANSS or ISC catalogs. Aligning on the P arrival and low-pass filtering (T>10 s) uncovers a surprise polarity flip of the large amplitude surface waves on vertical seismograms for some aftershocks relative to the main shock. We performed regional moment tensor inversions of the main shock and its largest aftershocks using complete three-component seismograms from stations distributed throughout the region to confirm the mechanism changes. Consistent with the GCMT solution, we find an E-W trending normal faulting mechanism for the main event and for one immediate aftershock. Two aftershocks indicate E-W trending reverse faulting with essentially flipped P- and T-axes relative to the normal faulting events (and the same B-axes). Within uncertainties, depths of the two event families are indistinguishable and indicate shallow faulting (<10 km). One intriguing possible interpretation is that both families ruptured the same fault with reverse mechanisms compensating for overshooting. However, activity could also be spatially separated either vertically (with reverse mechanisms possibly below extension) or laterally. The shallow source depth and the 200-km long uplifted chain of islands indicate that larger, shallow and thus potentially tsunamigenic earthquakes could occur just

  15. Allocating resources between network nodes for providing a network node function

    OpenAIRE

    Strijkers, R.J.; Meulenhoff, P.J.

    2014-01-01

    The invention provides a method wherein a first network node advertises available resources that a second network node may use to offload network node functions transparently to the first network node. Examples of the first network node are a client device (e.g. PC, notebook, tablet, smart phone), a server (e.g. application server, a proxy server, cloud location, router). Examples of the second network node are an application server, a cloud location or a router. The available resources may b...

  16. Outbreaks source: A new mathematical approach to identify their possible location

    Science.gov (United States)

    Buscema, Massimo; Grossi, Enzo; Breda, Marco; Jefferson, Tom

    2009-11-01

    Classical epidemiology has generally relied on the description and explanation of the occurrence of infectious diseases in relation to time occurrence of events rather than to place of occurrence. In recent times, computer generated dot maps have facilitated the modeling of the spread of infectious epidemic diseases either with classical statistics approaches or with artificial “intelligent systems”. Few attempts, however, have been made so far to identify the origin of the epidemic spread rather than its evolution by mathematical topology methods. We report on the use of a new artificial intelligence method (the H-PST Algorithm) and we compare this new technique with other well known algorithms to identify the source of three examples of infectious disease outbreaks derived from literature. The H-PST algorithm is a new system able to project a distances matrix of points (events) into a bi-dimensional space, with the generation of a new point, named hidden unit. This new hidden unit deforms the original Euclidean space and transforms it into a new space (cognitive space). The cost function of this transformation is the minimization of the differences between the original distance matrix among the assigned points and the distance matrix of the same points projected into the bi-dimensional map (or any different set of constraints). For many reasons we will discuss, the position of the hidden unit shows to target the outbreak source in many epidemics much better than the other classic algorithms specifically targeted for this task. Compared with main algorithms known in the location theory, the hidden unit was within yards of the outbreak source in the first example (the 2007 epidemic of Chikungunya fever in Italy). The hidden unit was located in the river between the two village epicentres of the spread exactly where the index case was living. Equally in the second (the 1967 foot and mouth disease epidemic in England), and the third (1854 London Cholera epidemic

  17. Location of aerodynamic noise sources from a 200 kW vertical-axis wind turbine

    Science.gov (United States)

    Ottermo, Fredric; Möllerström, Erik; Nordborg, Anders; Hylander, Jonny; Bernhoff, Hans

    2017-07-01

    Noise levels emitted from a 200 kW H-rotor vertical-axis wind turbine have been measured using a microphone array at four different positions, each at a hub-height distance from the tower. The microphone array, comprising 48 microphones in a spiral pattern, allows for directional mapping of the noise sources in the range of 500 Hz to 4 kHz. The produced images indicate that most of the noise is generated in a narrow azimuth-angle range, compatible with the location where increased turbulence is known to be present in the flow, as a result of the previous passage of a blade and its support arms. It is also shown that a semi-empirical model for inflow-turbulence noise seems to produce noise levels of the correct order of magnitude, based on the amount of turbulence that could be expected from power extraction considerations.

  18. Stress Tolerance Variations in Saccharomyces cerevisiae Strains from Diverse Ecological Sources and Geographical Locations.

    Directory of Open Access Journals (Sweden)

    Yan-Lin Zheng

    Full Text Available The budding yeast Saccharomyces cerevisiae is a platform organism for bioethanol production from various feedstocks and robust strains are desirable for efficient fermentation because yeast cells inevitably encounter stressors during the process. Recently, diverse S. cerevisiae lineages were identified, which provided novel resources for understanding stress tolerance variations and related shaping factors in the yeast. This study characterized the tolerance of diverse S. cerevisiae strains to the stressors of high ethanol concentrations, temperature shocks, and osmotic stress. The results showed that the isolates from human-associated environments overall presented a higher level of stress tolerance compared with those from forests spared anthropogenic influences. Statistical analyses indicated that the variations of stress tolerance were significantly correlated with both ecological sources and geographical locations of the strains. This study provides guidelines for selection of robust S. cerevisiae strains for bioethanol production from nature.

  19. Preprocessor with spline interpolation for converting stereolithography into cutter location source data

    Science.gov (United States)

    Nagata, Fusaomi; Okada, Yudai; Sakamoto, Tatsuhiko; Kusano, Takamasa; Habib, Maki K.; Watanabe, Keigo

    2017-06-01

    The authors have developed earlier an industrial machining robotic system for foamed polystyrene materials. The developed robotic CAM system provided a simple and effective interface without the need to use any robot language between operators and the machining robot. In this paper, a preprocessor for generating Cutter Location Source data (CLS data) from Stereolithography (STL data) is first proposed for robotic machining. The preprocessor enables to control the machining robot directly using STL data without using any commercially provided CAM system. The STL deals with a triangular representation for a curved surface geometry. The preprocessor allows machining robots to be controlled through a zigzag or spiral path directly calculated from STL data. Then, a smart spline interpolation method is proposed and implemented for smoothing coarse CLS data. The effectiveness and potential of the developed approaches are demonstrated through experiments on actual machining and interpolation.

  20. HPSLPred: An Ensemble Multi-Label Classifier for Human Protein Subcellular Location Prediction with Imbalanced Source.

    Science.gov (United States)

    Wan, Shixiang; Duan, Yucong; Zou, Quan

    2017-09-01

    Predicting the subcellular localization of proteins is an important and challenging problem. Traditional experimental approaches are often expensive and time-consuming. Consequently, a growing number of research efforts employ a series of machine learning approaches to predict the subcellular location of proteins. There are two main challenges among the state-of-the-art prediction methods. First, most of the existing techniques are designed to deal with multi-class rather than multi-label classification, which ignores connections between multiple labels. In reality, multiple locations of particular proteins imply that there are vital and unique biological significances that deserve special focus and cannot be ignored. Second, techniques for handling imbalanced data in multi-label classification problems are necessary, but never employed. For solving these two issues, we have developed an ensemble multi-label classifier called HPSLPred, which can be applied for multi-label classification with an imbalanced protein source. For convenience, a user-friendly webserver has been established at http://server.malab.cn/HPSLPred. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Site Characterization of the Source Physics Experiment Phase II Location Using Seismic Reflection Data

    Science.gov (United States)

    Sexton, E. A.; Snelson, C. M.; Chipman, V.; Emer, D. F.; White, R. L.; Emmitt, R.; Wright, A. A.; Drellack, S.; Huckins-Gang, H.; Mercadante, J.; Floyd, M.; McGowin, C.; Cothrun, C.; Bonal, N.

    2013-12-01

    An objective of the Source Physics Experiment (SPE) is to identify low-yield nuclear explosions from a regional distance. Low-yield nuclear explosions can often be difficult to discriminate among the clutter of natural and man-made explosive events (e.g., earthquakes and mine blasts). The SPE is broken into three phases. Phase I has provided the first of the physics-based data to test the empirical models that have been used to discriminate nuclear events. The Phase I series of tests were placed within a highly fractured granite body. The evolution of the project has led to development of Phase II, to be placed within the opposite end member of geology, an alluvium environment, thereby increasing the database of waveforms to build upon in the discrimination models. Both the granite and alluvium sites have hosted nearby nuclear tests, which provide comparisons for the chemical test data. Phase III of the SPE is yet to be determined. For Phase II of the experiment, characterization of the location is required to develop the geologic/geophysical models for the execution of the experiment. Criteria for the location are alluvium thickness of approximately 170 m and a water table below 170 m; minimal fracturing would be ideal. A P-wave mini-vibroseis survey was conducted at a potential site in alluvium to map out the subsurface geology. The seismic reflection profile consisted of 168 geophone stations, spaced 5 m apart. The mini-vibe was a 7,000-lb peak-force source, starting 57.5 m off the north end of the profile and ending 57.5 m past the southern-most geophone. The length of the profile was 835 m. The source points were placed every 5 m, equally spaced between geophones to reduce clipping. The vibroseis sweep was from 20 Hz down to 180 Hz over 8 seconds, and four sweeps were stacked at each shot location. The shot gathers show high signal-to-noise ratios with clear first arrivals across the entire spread and the suggestion of some shallow reflectors. The data were

  2. Location, location, location

    NARCIS (Netherlands)

    Anderson, S.P.; Goeree, J.K.; Ramer, R.

    1997-01-01

    We analyze the canonical location-then-price duopoly game with general log- concave consumer densities. A unique pure-strategy equilibrium to the two-stage game exists if the density is not "too asymmetric" and not "too concave." These criteria are satisfied by many commonly used densities.

  3. Sound Spectrum Influences Auditory Distance Perception of Sound Sources Located in a Room Environment

    Directory of Open Access Journals (Sweden)

    Ignacio Spiousas

    2017-06-01

    Full Text Available Previous studies on the effect of spectral content on auditory distance perception (ADP focused on the physically measurable cues occurring either in the near field (low-pass filtering due to head diffraction or when the sound travels distances >15 m (high-frequency energy losses due to air absorption. Here, we study how the spectrum of a sound arriving from a source located in a reverberant room at intermediate distances (1–6 m influences the perception of the distance to the source. First, we conducted an ADP experiment using pure tones (the simplest possible spectrum of frequencies 0.5, 1, 2, and 4 kHz. Then, we performed a second ADP experiment with stimuli consisting of continuous broadband and bandpass-filtered (with center frequencies of 0.5, 1.5, and 4 kHz and bandwidths of 1/12, 1/3, and 1.5 octave pink-noise clips. Our results showed an effect of the stimulus frequency on the perceived distance both for pure tones and filtered noise bands: ADP was less accurate for stimuli containing energy only in the low-frequency range. Analysis of the frequency response of the room showed that the low accuracy observed for low-frequency stimuli can be explained by the presence of sparse modal resonances in the low-frequency region of the spectrum, which induced a non-monotonic relationship between binaural intensity and source distance. The results obtained in the second experiment suggest that ADP can also be affected by stimulus bandwidth but in a less straightforward way (i.e., depending on the center frequency, increasing stimulus bandwidth could have different effects. Finally, the analysis of the acoustical cues suggests that listeners judged source distance using mainly changes in the overall intensity of the auditory stimulus with distance rather than the direct-to-reverberant energy ratio, even for low-frequency noise bands (which typically induce high amount of reverberation. The results obtained in this study show that, depending on

  4. Testing seismic amplitude source location for fast debris-flow detection at Illgraben, Switzerland

    Science.gov (United States)

    Walter, Fabian; Burtin, Arnaud; McArdell, Brian W.; Hovius, Niels; Weder, Bianca; Turowski, Jens M.

    2017-06-01

    Heavy precipitation can mobilize tens to hundreds of thousands of cubic meters of sediment in steep Alpine torrents in a short time. The resulting debris flows (mixtures of water, sediment and boulders) move downstream with velocities of several meters per second and have a high destruction potential. Warning protocols for affected communities rely on raising awareness about the debris-flow threat, precipitation monitoring and rapid detection methods. The latter, in particular, is a challenge because debris-flow-prone torrents have their catchments in steep and inaccessible terrain, where instrumentation is difficult to install and maintain. Here we test amplitude source location (ASL) as a processing scheme for seismic network data for early warning purposes. We use debris-flow and noise seismograms from the Illgraben catchment, Switzerland, a torrent system which produces several debris-flow events per year. Automatic in situ detection is currently based on geophones mounted on concrete check dams and radar stage sensors suspended above the channel. The ASL approach has the advantage that it uses seismometers, which can be installed at more accessible locations where a stable connection to mobile phone networks is available for data communication. Our ASL processing uses time-averaged ground vibration amplitudes to estimate the location of the debris-flow front. Applied to continuous data streams, inversion of the seismic amplitude decay throughout the network is robust and efficient, requires no manual identification of seismic phase arrivals and eliminates the need for a local seismic velocity model. We apply the ASL technique to a small debris-flow event on 19 July 2011, which was captured with a temporary seismic monitoring network. The processing rapidly detects the debris-flow event half an hour before arrival at the outlet of the torrent and several minutes before detection by the in situ alarm system. An analysis of continuous seismic records furthermore

  5. Testing seismic amplitude source location for fast debris-flow detection at Illgraben, Switzerland

    Directory of Open Access Journals (Sweden)

    F. Walter

    2017-06-01

    Full Text Available Heavy precipitation can mobilize tens to hundreds of thousands of cubic meters of sediment in steep Alpine torrents in a short time. The resulting debris flows (mixtures of water, sediment and boulders move downstream with velocities of several meters per second and have a high destruction potential. Warning protocols for affected communities rely on raising awareness about the debris-flow threat, precipitation monitoring and rapid detection methods. The latter, in particular, is a challenge because debris-flow-prone torrents have their catchments in steep and inaccessible terrain, where instrumentation is difficult to install and maintain. Here we test amplitude source location (ASL as a processing scheme for seismic network data for early warning purposes. We use debris-flow and noise seismograms from the Illgraben catchment, Switzerland, a torrent system which produces several debris-flow events per year. Automatic in situ detection is currently based on geophones mounted on concrete check dams and radar stage sensors suspended above the channel. The ASL approach has the advantage that it uses seismometers, which can be installed at more accessible locations where a stable connection to mobile phone networks is available for data communication. Our ASL processing uses time-averaged ground vibration amplitudes to estimate the location of the debris-flow front. Applied to continuous data streams, inversion of the seismic amplitude decay throughout the network is robust and efficient, requires no manual identification of seismic phase arrivals and eliminates the need for a local seismic velocity model. We apply the ASL technique to a small debris-flow event on 19 July 2011, which was captured with a temporary seismic monitoring network. The processing rapidly detects the debris-flow event half an hour before arrival at the outlet of the torrent and several minutes before detection by the in situ alarm system. An analysis of continuous seismic

  6. Localizing and placement of network node functions in a network

    NARCIS (Netherlands)

    Strijkers, R.J.; Meulenhoff, P.J.

    2014-01-01

    The invention enables placement and use of a network node function in a second network node instead of using the network node function in a first network node. The network node function is e.g. a server function or a router function. The second network node is typically located in or close to the

  7. Locating non-volcanic tremor along the San Andreas Fault using a multiple array source imaging technique

    Science.gov (United States)

    Ryberg, T.; Haberland, C.H.; Fuis, G.S.; Ellsworth, W.L.; Shelly, D.R.

    2010-01-01

    Non-volcanic tremor (NVT) has been observed at several subduction zones and at the San Andreas Fault (SAF). Tremor locations are commonly derived by cross-correlating envelope-transformed seismic traces in combination with source-scanning techniques. Recently, they have also been located by using relative relocations with master events, that is low-frequency earthquakes that are part of the tremor; locations are derived by conventional traveltime-based methods. Here we present a method to locate the sources of NVT using an imaging approach for multiple array data. The performance of the method is checked with synthetic tests and the relocation of earthquakes. We also applied the method to tremor occurring near Cholame, California. A set of small-aperture arrays (i.e. an array consisting of arrays) installed around Cholame provided the data set for this study. We observed several tremor episodes and located tremor sources in the vicinity of SAF. During individual tremor episodes, we observed a systematic change of source location, indicating rapid migration of the tremor source along SAF. ?? 2010 The Authors Geophysical Journal International ?? 2010 RAS.

  8. Benthic Foraminifers identify the source of displaced sediment from a sediment density flow at 1840 m near the Seafloor Instrument Node of the Monterey Coordinated Canyon Experiment

    Science.gov (United States)

    McGann, M.; Maier, K. L.; Gales, J. A.; Paull, C. K.; Gwiazda, R.; Barry, J.; Carvajal, C.; Clare, M. A.; Cartigny, M.; Chaffey, M. R.; Parsons, D. R.; O'Reilly, T. C.; Rosenberger, K. J.; Wolfson-Schwehr, M.; Simmons, S.; Sumner, E.; Talling, P.; Xu, J.

    2017-12-01

    Submarine canyons are found along the slopes of most continental margins and turbidity currents are thought to be the primary mechanism responsible for transporting sediment through them to deep-sea fans. The initiation sites of these flows are difficult to locate with any degree of precision from lithology alone. Fortunately, the presence of allochthonous microscopic remains, such as benthic foraminifers, can aid in the identification of the source of the displaced sediments. In Monterey Canyon, offshore California, a Seafloor Instrument Node (SIN) and adjacent mooring in the Coordinated Canyon Experiment indicate that a February 2017 turbidity current reached 1840 m water depth. In April 2017, one push core was obtained on each of four sides of the SIN just outside its frame and six others from 30-100 m away. Each was cut into 1 cm slices, stained with rose Bengal, washed, and analyzed for their microscopic constituents. Material recovered included terrestrial debris (wood, leaves, seeds, highway safety spheres, and volcanic glass) as well as foraminiferal tests. Dead benthic foraminifers from the estuarine (0-10 m), inner shelf (0-50 m), outer shelf (50-150 m), slope break (150 m), upper bathyal (150-500 m), and middle bathyal (500-2000 m) biofacies were present, suggesting a staged progression of sediment downslope from the continental shelf and slope. Living (rose Bengal stained) foraminifers recovered represent estuarine (Ammonia tepida, Elphidium excavatum), inner shelf (Buccella frigida, B. tenerrima, Buliminella elegantissima, Cibicides fletcheri, Nonionella spp., Rotorbinella turbinata), and upper bathyal (Bolivina pacifica, B. spissa, Epistominella exigua, Uvigerina peregrina) species as well as an in-situ middle bathyal biofacies (Bolivina argentea, B. spissa, Buliminella tenuata, Epistominella pacifica, Globobulimina spp., Uvigerina peregrina, U. hispida). The presence of living allochthonous benthic foraminifers from these shallower biofacies suggests

  9. Tracking the MSL-SAM methane detection source location Through Mars Regional Atmospheric Modeling System (MRAMS)

    Science.gov (United States)

    Pla-García, Jorge

    2016-04-01

    1. Introduction: The putative in situ detection of methane by Sample Analysis at Mars (SAM) instrument suite on Curiosi-ty at Gale crater has garnered significant attention because of the potential implications for the presence of geological methane sources or indigenous Martian organisms [1, 2]. SAM reported detection of back-ground levels of atmospheric methane of mean value 0.69±0.25 parts per billion by volume (ppbv) at the 95% confidence interval (CI). Additionally, in four sequential measurements spanning a 60-sol period, SAM observed elevated levels of methane of 7.2±2.1 ppbv (95% CI), implying that Mars is episodically producing methane from an additional unknown source. There are many major unresolved questions regard-ing this detection: 1) What are the potential sources of the methane release? 2) What causes the rapid decrease in concentration? and 3) Where is the re-lease location? 4) How spatially extensive is the re-lease? 5) For how long is CH4 released? Regarding the first question, the source of methane, is so far not identified. It could be related with geo-logical process like methane release from clathrates [3], serpentinisation [4] and volcanism [5]; or due to biological activity from methanogenesis [6]. To answer the second question, the rapid decrease in concentration, it is important to note that the photo-chemical lifetime of methane is of order 100 years, much longer than the atmospheric mixing time scale, and thus the gas should tend to be well mixed except near a source or shortly after an episodic release. The observed spike of 7 ppb from the background of System (MRAMS). The model was focused on rover locations using nested grids with a spacing of 330 meters on the in-nermost grid that is centered over the landing [8, 9]. MRAMS is ideally suited for this investigation; the model is explicitly designed to simulate Mars' at-mospheric circulations at the mesoscale and smaller with realistic, high-resolution surface properties [10, 11

  10. Source Population and Acceleration Location of Suprathermal Heavy Ions in Corotating Interaction Regions

    Energy Technology Data Exchange (ETDEWEB)

    Filwett, R. J.; Desai, M. I. [University of Texas at San Antonio, San Antonio, TX (United States); Dayeh, M. A.; Broiles, T. W. [Southwest Research Institute, San Antonio, TX (United States)

    2017-03-20

    We have analyzed the ∼20–320 keV nucleon{sup −1} suprathermal (ST) heavy ion abundances in 41 corotating interaction regions (CIRs) observed by the Wind spacecraft from 1995 January to 2008 December. Our results are: (1) the CIR Fe/CNO and NeS/CNO ratios vary with the sunspot number, with values being closer to average solar energetic particle event values during solar maxima and lower than nominal solar wind values during solar minima. The physical mechanism responsible for the depleted abundances during solar minimum remains an open question. (2) The Fe/CNO increases with energy in the 6 events that occurred during solar maximum, while no such trends are observed for the 35 events during solar minimum. (3) The Fe/CNO shows no correlation with the average solar wind speed. (4) The Fe/CNO is well correlated with the corresponding upstream ∼20–320 keV nucleon{sup −1} Fe/CNO and not with the solar wind Fe/O measured by ACE in 31 events. Using the correlations between the upstream ∼20–40 keV nucleon{sup −1} Fe/CNO and the ∼20–320 keV nucleon{sup −1} Fe/CNO in CIRs, we estimate that, on average, the ST particles traveled ∼2 au along the nominal Parker spiral field line, which corresponds to upper limits for the radial distance of the source or acceleration location of ∼1 au beyond Earth orbit. Our results are consistent with those obtained from recent surveys, and confirm that CIR ST heavy ions are accelerated more locally, and are at odds with the traditional viewpoint that CIR ions seen at 1 au are bulk solar wind ions accelerated between 3 and 5 au.

  11. Gas Well Top Hole Locations, LP and LNG - Marcellus Gas Well Water Sources View

    Data.gov (United States)

    NSGIC Education | GIS Inventory — This data set contains all approved water sources within water managment plans (WMP). A WMP contains water sources utilized in the fracture stimulation of Marcellus...

  12. Sentinel nodes outside lymph node basins in patients with melanoma

    NARCIS (Netherlands)

    Roozendaal, GK; de Vries, JDH; van Poll, D; Jansen, L; Nieweg, OE; Kroon, BBR; Schraffordt Koops, H.

    Background: Lymphoscintigraphy occasionally reveals hot spots outside lymph node basins in patients with melanoma. The aim of this study was to evaluate such abnormally located hot spots. Methods: Sentinel node biopsy was studied prospectively in 379 patients with clinically localized cutaneous

  13. Joint sensor location/power rating optimization for temporally-correlated source estimation

    KAUST Repository

    Bushnaq, Osama M.; Chaaban, Anas; Al-Naffouri, Tareq Y.

    2017-01-01

    via wireless AWGN channel. In addition to selecting the optimal sensing location, the sensor type to be placed in these locations is selected from a pool of T sensor types such that different sensor types have different power ratings and costs

  14. Joint sensor location/power rating optimization for temporally-correlated source estimation

    KAUST Repository

    Bushnaq, Osama M.

    2017-12-22

    The optimal sensor selection for scalar state parameter estimation in wireless sensor networks is studied in the paper. A subset of N candidate sensing locations is selected to measure a state parameter and send the observation to a fusion center via wireless AWGN channel. In addition to selecting the optimal sensing location, the sensor type to be placed in these locations is selected from a pool of T sensor types such that different sensor types have different power ratings and costs. The sensor transmission power is limited based on the amount of energy harvested at the sensing location and the type of the sensor. The Kalman filter is used to efficiently obtain the MMSE estimator at the fusion center. Sensors are selected such that the MMSE estimator error is minimized subject to a prescribed system budget. This goal is achieved using convex relaxation and greedy algorithm approaches.

  15. Accurate source location from waves scattered by surface topography: Applications to the Nevada and North Korean test sites

    Science.gov (United States)

    Shen, Y.; Wang, N.; Bao, X.; Flinders, A. F.

    2016-12-01

    Scattered waves generated near the source contains energy converted from the near-field waves to the far-field propagating waves, which can be used to achieve location accuracy beyond the diffraction limit. In this work, we apply a novel full-wave location method that combines a grid-search algorithm with the 3D Green's tensor database to locate the Non-Proliferation Experiment (NPE) at the Nevada test site and the North Korean nuclear tests. We use the first arrivals (Pn/Pg) and their immediate codas, which are likely dominated by waves scattered at the surface topography near the source, to determine the source location. We investigate seismograms in the frequency of [1.0 2.0] Hz to reduce noises in the data and highlight topography scattered waves. High resolution topographic models constructed from 10 and 90 m grids are used for Nevada and North Korea, respectively. The reference velocity model is based on CRUST 1.0. We use the collocated-grid finite difference method on curvilinear grids to calculate the strain Green's tensor and obtain synthetic waveforms using source-receiver reciprocity. The `best' solution is found based on the least-square misfit between the observed and synthetic waveforms. To suppress random noises, an optimal weighting method for three-component seismograms is applied in misfit calculation. Our results show that the scattered waves are crucial in improving resolution and allow us to obtain accurate solutions with a small number of stations. Since the scattered waves depends on topography, which is known at the wavelengths of regional seismic waves, our approach yields absolute, instead of relative, source locations. We compare our solutions with those of USGS and other studies. Moreover, we use differential waveforms to locate pairs of the North Korea tests from years 2006, 2009, 2013 and 2016 to further reduce the effects of unmodeled heterogeneities and errors in the reference velocity model.

  16. Avoiding radiation exposure while training to locate a radioactive source: a virtual reality exercise

    International Nuclear Information System (INIS)

    Marins, E.R.; Cotelli do Espírito Santo, A.; Abreu Mól, A. C. de; Cunha, G.; Landau, L.

    2015-01-01

    A technician undergoing radioprotection training must learn to use radiation detectors. Practical exercises involve being near to radiation sources. The work here presented reduces the exposure to individuals using a virtual environment to achieve preliminary apprenticeship prior using real radioactive sources. (authors)

  17. Efficient Location of Research Reference Sources in the Field of Dance.

    Science.gov (United States)

    Kissinger, Pat; Jay, Danielle

    More than 45 basic dance reference research sources that would be useful to students, scholars, teachers, historians, and therapists are discussed in this bibliographic essay. Aspects of dance covered include choreography, criticism, teaching principles, aesthetic theory, dance therapy, and history. Sources are grouped by type: dictionaries and…

  18. Source apportionment and location by selective wind sampling and Positive Matrix Factorization.

    Science.gov (United States)

    Venturini, Elisa; Vassura, Ivano; Raffo, Simona; Ferroni, Laura; Bernardi, Elena; Passarini, Fabrizio

    2014-10-01

    In order to determine the pollution sources in a suburban area and identify the main direction of their origin, PM2.5 was collected with samplers coupled with a wind select sensor and then subjected to Positive Matrix Factorization (PMF) analysis. In each sample, soluble ions, organic carbon, elemental carbon, levoglucosan, metals, and Polycyclic Aromatic Hydrocarbons (PAHs) were determined. PMF results identified six main sources affecting the area: natural gas home appliances, motor vehicles, regional transport, biomass combustion, manufacturing activities, and secondary aerosol. The connection of factor temporal trends with other parameters (i.e., temperature, PM2.5 concentration, and photochemical processes) confirms factor attributions. PMF analysis indicated that the main source of PM2.5 in the area is secondary aerosol. This should be mainly due to regional contributions, owing to both the secondary nature of the source itself and the higher concentration registered in inland air masses. The motor vehicle emission source contribution is also important. This source likely has a prevalent local origin. The most toxic determined components, i.e., PAHs, Cd, Pb, and Ni, are mainly due to vehicular traffic. Even if this is not the main source in the study area, it is the one of greatest concern. The application of PMF analysis to PM2.5 collected with this new sampling technique made it possible to obtain more detailed results on the sources affecting the area compared to a classical PMF analysis.

  19. Source contributions to PM2.5 and PM10 at an urban background and a street location

    NARCIS (Netherlands)

    Keuken, M. P.; Moerman, M.; Voogt, M.; Blom, M.; Weijers, E. P.; Rockmann, T.; Dusek, U.

    The contribution of regional, urban and traffic sources to PM2.5 and PM10 in an urban area was investigated in this study. The chemical composition of PM2.5 and PM10 was measured over a year at a street location and up- and down-wind of the city of Rotterdam, the Netherlands. The C-14 content in EC

  20. Source contributions to PM2.5 and PM10 at an urban background and a street location

    NARCIS (Netherlands)

    Keuken, M.P.; Moerman, M.M.; Voogt, M.H.

    2013-01-01

    The contribution of regional, urban and traffic sources to PM2.5 and PM10 in an urban area was investigated in this study. The chemical composition of PM2.5 and PM10 was measured over a year at a street location and up- and down-wind of the city of Rotterdam, the Netherlands. The 14C content in EC

  1. Tree Coring as a Complement to Soil Gas Screening to Locate PCE and TCE Source Zones and Hot Spots

    DEFF Research Database (Denmark)

    Nielsen, Mette Algreen; Trapp, Stefan; Rehne Jensen, Pernille

    2015-01-01

    ) or trichloroethylene (TCE) to evaluate their ability to locate source zones and contaminant hot spots. One test site represented a relatively homogeneous sandy soil and aquifer, and the second a more heterogeneous geology with both sandy and less permeable clay till layers overlying a chalk aquifer. Tree cores from...

  2. NRC/UBC Node

    Energy Technology Data Exchange (ETDEWEB)

    Ellis-Perry, B. [Univ. of British Columbia, Vancouver, British Columbia (Canada); Yogendran, Y. [NRC Inst. for Fuel Cell Innovation, Vancouver, British Columbia (Canada)

    2004-07-01

    'Full text:' In the search for cleaner, more sustainable energy sources, many of the most promising breakthroughs have been in hydrogen technology. However, this promise will remain unfulfilled without public interest and enthusiasm, and without the infrastructure to support the technology. In order to get there, we have to test, perfect, and demonstrate technology that is safe and affordable, and we must do so in practical, familiar settings. Ideally, such settings should be easily accessible to the engineers, planners, and architects of tomorrow while providing a showcase for hydrogen technology that will attract the general public. This place is the NRC/UBC Hydrogen Node. The UBC campus in Point Grey is home to leading edge, internationally recognized researchers in a range of disciplines, both within the University and at the NRC Institute for Fuel Cell Innovation. On average, 40,000 students, faculty, and staff use the campus every day; UBC graduates go on to leadership positions in communities around the globe. Its spectacular setting makes UBC a popular destination for thousands of visitors from around the world. In 2006 UBC will host the World Urban Forum, and in 2010 it will be one of the sites for the Vancouver-Whistler Olympic Games. UBC and its South Campus neighbourhoods are developing as a model sustainable community, offering an excellent opportunity to develop and showcase hydrogen infrastructure and technology in a real-life, attractive setting that will be seen by thousands of people around the world. UBC's facilities, location, and Trek 2010 commitment to excellence in learning, research, and sustainability make it an ideal location for such a project. The H2 Village at UBC will be an integrated hydrogen demonstration project, linked to the hydrogen highway. This project is bringing together leading companies, researchers, and government agencies committed to making the refinement and early adoption of safe hydrogen technology a

  3. NRC/UBC Node

    International Nuclear Information System (INIS)

    Ellis-Perry, B.; Yogendran, Y.

    2004-01-01

    'Full text:' In the search for cleaner, more sustainable energy sources, many of the most promising breakthroughs have been in hydrogen technology. However, this promise will remain unfulfilled without public interest and enthusiasm, and without the infrastructure to support the technology. In order to get there, we have to test, perfect, and demonstrate technology that is safe and affordable, and we must do so in practical, familiar settings. Ideally, such settings should be easily accessible to the engineers, planners, and architects of tomorrow while providing a showcase for hydrogen technology that will attract the general public. This place is the NRC/UBC Hydrogen Node. The UBC campus in Point Grey is home to leading edge, internationally recognized researchers in a range of disciplines, both within the University and at the NRC Institute for Fuel Cell Innovation. On average, 40,000 students, faculty, and staff use the campus every day; UBC graduates go on to leadership positions in communities around the globe. Its spectacular setting makes UBC a popular destination for thousands of visitors from around the world. In 2006 UBC will host the World Urban Forum, and in 2010 it will be one of the sites for the Vancouver-Whistler Olympic Games. UBC and its South Campus neighbourhoods are developing as a model sustainable community, offering an excellent opportunity to develop and showcase hydrogen infrastructure and technology in a real-life, attractive setting that will be seen by thousands of people around the world. UBC's facilities, location, and Trek 2010 commitment to excellence in learning, research, and sustainability make it an ideal location for such a project. The H2 Village at UBC will be an integrated hydrogen demonstration project, linked to the hydrogen highway. This project is bringing together leading companies, researchers, and government agencies committed to making the refinement and early adoption of safe hydrogen technology a reality

  4. Locating sensors for detecting source-to-target patterns of special nuclear material smuggling: a spatial information theoretic approach.

    Science.gov (United States)

    Przybyla, Jay; Taylor, Jeffrey; Zhou, Xuesong

    2010-01-01

    In this paper, a spatial information-theoretic model is proposed to locate sensors for detecting source-to-target patterns of special nuclear material (SNM) smuggling. In order to ship the nuclear materials from a source location with SNM production to a target city, the smugglers must employ global and domestic logistics systems. This paper focuses on locating a limited set of fixed and mobile radiation sensors in a transportation network, with the intent to maximize the expected information gain and minimize the estimation error for the subsequent nuclear material detection stage. A Kalman filtering-based framework is adapted to assist the decision-maker in quantifying the network-wide information gain and SNM flow estimation accuracy.

  5. Locating Sensors for Detecting Source-to-Target Patterns of Special Nuclear Material Smuggling: A Spatial Information Theoretic Approach

    Directory of Open Access Journals (Sweden)

    Xuesong Zhou

    2010-08-01

    Full Text Available In this paper, a spatial information-theoretic model is proposed to locate sensors for detecting source-to-target patterns of special nuclear material (SNM smuggling. In order to ship the nuclear materials from a source location with SNM production to a target city, the smugglers must employ global and domestic logistics systems. This paper focuses on locating a limited set of fixed and mobile radiation sensors in a transportation network, with the intent to maximize the expected information gain and minimize the estimation error for the subsequent nuclear material detection stage. A Kalman filtering-based framework is adapted to assist the decision-maker in quantifying the network-wide information gain and SNM flow estimation accuracy.

  6. Source contribution of PM₂.₅ at different locations on the Malaysian Peninsula.

    Science.gov (United States)

    Ee-Ling, Ooi; Mustaffa, Nur Ili Hamizah; Amil, Norhaniza; Khan, Md Firoz; Latif, Mohd Talib

    2015-04-01

    This study determined the source contribution of PM2.5 (particulate matter heavy metals. Principal component analysis with multilinear regressions were used to identify the possible sources of PM2.5. The range of PM2.5 was between 10 ± 3 and 30 ± 7 µg m(-3). Sulfate (SO4 (2-)) was the major ionic compound detected and zinc was found to dominate the heavy metals. Source apportionment analysis revealed that motor vehicle and soil dust dominated the composition of PM2.5 in the urban area. Domestic waste combustion dominated in the suburban area, while biomass burning dominated in the rural area.

  7. Bayesian inverse modeling and source location of an unintended 131I release in Europe in the fall of 2011

    Science.gov (United States)

    Tichý, Ondřej; Šmídl, Václav; Hofman, Radek; Šindelářová, Kateřina; Hýža, Miroslav; Stohl, Andreas

    2017-10-01

    In the fall of 2011, iodine-131 (131I) was detected at several radionuclide monitoring stations in central Europe. After investigation, the International Atomic Energy Agency (IAEA) was informed by Hungarian authorities that 131I was released from the Institute of Isotopes Ltd. in Budapest, Hungary. It was reported that a total activity of 342 GBq of 131I was emitted between 8 September and 16 November 2011. In this study, we use the ambient concentration measurements of 131I to determine the location of the release as well as its magnitude and temporal variation. As the location of the release and an estimate of the source strength became eventually known, this accident represents a realistic test case for inversion models. For our source reconstruction, we use no prior knowledge. Instead, we estimate the source location and emission variation using only the available 131I measurements. Subsequently, we use the partial information about the source term available from the Hungarian authorities for validation of our results. For the source determination, we first perform backward runs of atmospheric transport models and obtain source-receptor sensitivity (SRS) matrices for each grid cell of our study domain. We use two dispersion models, FLEXPART and Hysplit, driven with meteorological analysis data from the global forecast system (GFS) and from European Centre for Medium-range Weather Forecasts (ECMWF) weather forecast models. Second, we use a recently developed inverse method, least-squares with adaptive prior covariance (LS-APC), to determine the 131I emissions and their temporal variation from the measurements and computed SRS matrices. For each grid cell of our simulation domain, we evaluate the probability that the release was generated in that cell using Bayesian model selection. The model selection procedure also provides information about the most suitable dispersion model for the source term reconstruction. Third, we select the most probable location of

  8. Bayesian inverse modeling and source location of an unintended 131I release in Europe in the fall of 2011

    Directory of Open Access Journals (Sweden)

    O. Tichý

    2017-10-01

    Full Text Available In the fall of 2011, iodine-131 (131I was detected at several radionuclide monitoring stations in central Europe. After investigation, the International Atomic Energy Agency (IAEA was informed by Hungarian authorities that 131I was released from the Institute of Isotopes Ltd. in Budapest, Hungary. It was reported that a total activity of 342 GBq of 131I was emitted between 8 September and 16 November 2011. In this study, we use the ambient concentration measurements of 131I to determine the location of the release as well as its magnitude and temporal variation. As the location of the release and an estimate of the source strength became eventually known, this accident represents a realistic test case for inversion models. For our source reconstruction, we use no prior knowledge. Instead, we estimate the source location and emission variation using only the available 131I measurements. Subsequently, we use the partial information about the source term available from the Hungarian authorities for validation of our results. For the source determination, we first perform backward runs of atmospheric transport models and obtain source-receptor sensitivity (SRS matrices for each grid cell of our study domain. We use two dispersion models, FLEXPART and Hysplit, driven with meteorological analysis data from the global forecast system (GFS and from European Centre for Medium-range Weather Forecasts (ECMWF weather forecast models. Second, we use a recently developed inverse method, least-squares with adaptive prior covariance (LS-APC, to determine the 131I emissions and their temporal variation from the measurements and computed SRS matrices. For each grid cell of our simulation domain, we evaluate the probability that the release was generated in that cell using Bayesian model selection. The model selection procedure also provides information about the most suitable dispersion model for the source term reconstruction. Third, we select the most

  9. Using web-sources for location based systems on mobile phones

    OpenAIRE

    Pannevis, M.; Marx, M.

    2008-01-01

    The paper describes the implementation of a context aware location and time based system on a normal mobile phone, with a minimum of requirements (Bluetooth, Internet access, Java ME, and a simple webbrowser). We can answer the following queries based on data crawled from the web and enriched with location coordinates: • Where are my friends? • What movies are playing, right here, right now? • I need to park my car. Where is the closest parking lot with free space? • What is a good place to h...

  10. Source term assessment using inverse modeling of radiation dose measured with environmental radiation monitors located at different positions

    International Nuclear Information System (INIS)

    Srinivas, C.V.; Rakesh, P.T.; Baskaran, R.; Venkatraman, B.

    2018-01-01

    Source term is an important input for consequence analysis using Decision Support Systems (DSS) to project radiological impact in the event of nuclear emergencies. A source term model called 'ASTER' is incorporated in the Online Nuclear Emergency Response System (ONERS) operational at Kalpakkam site for decision making during nuclear emergencies. This computes release rates using inverse method by employing an atmospheric dispersion model and gamma dose rates measured by environmental radiation monitors (ERM) deployed around the nuclear plant. The estimates may depend on the distribution of ERMs around the release location. In this work, data from various gamma monitors located at different radii 0.75 km and 1.5 km is used to assess the accuracy in the source term estimation for stack releases of MAPS-PHWR at Kalpakkam

  11. Location of odor sources and the affected population in Imperial County, California

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, J.L.

    1981-08-01

    This report is divided into four sections. The first two sections contain general background information on Imperial County. The third section is a general discussion of odor sources in Imperial County, and the fourth maps the specific odor sources, the expected areas of perception, and the affected populations. this mapping is done for the Imperial Valley and each of the four Imperial County KGRA's (Known Geothermal Resource Areas) where odor from the development of the geothermal energy may affect population.

  12. Using web-sources for location based systems on mobile phones

    NARCIS (Netherlands)

    Pannevis, M.; Marx, M.

    2008-01-01

    The paper describes the implementation of a context aware location and time based system on a normal mobile phone, with a minimum of requirements (Bluetooth, Internet access, Java ME, and a simple webbrowser). We can answer the following queries based on data crawled from the web and enriched with

  13. Maximizing survivability of acyclic transmission networks with multi-state retransmitters and vulnerable nodes

    International Nuclear Information System (INIS)

    Levitin, Gregory

    2002-01-01

    In this paper, an algorithm for optimal allocation of multi-state elements (MEs) in acyclic transmission networks (ATNs) with vulnerable nodes is suggested. The ATNs consist of a number of positions (nodes) in which MEs capable of receiving and sending a signal are allocated. Each network has a root position where the signal source is located, a number of leaf positions that can only receive a signal, and a number of intermediate positions containing MEs capable of transmitting the received signal to some other nodes. Each ME that is located in a nonleaf node can have different states determined by a set of nodes receiving the signal directly from this ME. The probability of each state is assumed to be known for each ME. Each ATN node with all the MEs allocated at this node can be destroyed by external impact (common cause failure) with a given probability. The ATN survivability is defined as the probability that a signal from the root node is transmitted to each leaf node. The optimal distribution of MEs with different characteristics among ATN positions provides the greatest possible ATN survivability. It is shown that the node vulnerability index affects the optimal distribution. The suggested algorithm is based on using a universal generating function technique for network survivability evaluation. A genetic algorithm is used as the optimization tool. Illustrative examples are presented

  14. Application Research of Horn Array Multi-Beam Antenna in Reference Source System for Satellite Interference Location

    Science.gov (United States)

    Zhou, Ping; Lin, Hui; Zhang, Qi

    2018-01-01

    The reference source system is a key factor to ensure the successful location of the satellite interference source. Currently, the traditional system used a mechanical rotating antenna which leaded to the disadvantages of slow rotation and high failure-rate, which seriously restricted the system’s positioning-timeliness and became its obvious weaknesses. In this paper, a multi-beam antenna scheme based on the horn array was proposed as a reference source for the satellite interference location, which was used as an alternative to the traditional reference source antenna. The new scheme has designed a small circularly polarized horn antenna as an element and proposed a multi-beamforming algorithm based on planar array. Moreover, the simulation analysis of horn antenna pattern, multi-beam forming algorithm and simulated satellite link cross-ambiguity calculation have been carried out respectively. Finally, cross-ambiguity calculation of the traditional reference source system has also been tested. The comparison between the results of computer simulation and the actual test results shows that the scheme is scientific and feasible, obviously superior to the traditional reference source system.

  15. New approach for location of continuously emitting acoustic emission sources by phase-controlled probe arrays

    International Nuclear Information System (INIS)

    Hoeller, P.; Klein, M.; Waschkies, E.; Deuster, G.

    1991-01-01

    Usually burst-like acoustic emission (AE) is localized by triangulation. For continuous AE, e.g. from leakages, this method is not feasible. Therefore a new method for localization of continuous AE has been developed. It is based on a phase-controlled probe array which consists of many single sensor elements. The AE signals received by the different sensor elements are delayed according to their time-of-flight differences from the source to the single elements of the receiver array. By choosing special combinations of time differences between the array elements the directivity pattern of the sensitivity of the array can be changed, e.g. rotated in the plane of a large plate. Thus, the source direction can be determined by one array. Some preliminary experiments with an artificial noise source, positioned on a large steel plate, have been performed and have demonstrated the feasibility of this approach. (orig.)

  16. Source location in plates based on the multiple sensors array method and wavelet analysis

    International Nuclear Information System (INIS)

    Yang, Hong Jun; Shin, Tae Jin; Lee, Sang Kwon

    2014-01-01

    A new method for impact source localization in a plate is proposed based on the multiple signal classification (MUSIC) and wavelet analysis. For source localization, the direction of arrival of the wave caused by an impact on a plate and the distance between impact position and sensor should be estimated. The direction of arrival can be estimated accurately using MUSIC method. The distance can be obtained by using the time delay of arrival and the group velocity of the Lamb wave in a plate. Time delay is experimentally estimated using the continuous wavelet transform for the wave. The elasto dynamic theory is used for the group velocity estimation.

  17. Source location in plates based on the multiple sensors array method and wavelet analysis

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Hong Jun; Shin, Tae Jin; Lee, Sang Kwon [Inha University, Incheon (Korea, Republic of)

    2014-01-15

    A new method for impact source localization in a plate is proposed based on the multiple signal classification (MUSIC) and wavelet analysis. For source localization, the direction of arrival of the wave caused by an impact on a plate and the distance between impact position and sensor should be estimated. The direction of arrival can be estimated accurately using MUSIC method. The distance can be obtained by using the time delay of arrival and the group velocity of the Lamb wave in a plate. Time delay is experimentally estimated using the continuous wavelet transform for the wave. The elasto dynamic theory is used for the group velocity estimation.

  18. Influence of Sound Source Location on the Behavior and Physiology of the Precedence Effect in Cats

    OpenAIRE

    Dent, Micheal L.; Tollin, Daniel J.; Yin, Tom C. T.

    2009-01-01

    Psychophysical experiments on the precedence effect (PE) in cats have shown that they localize pairs of auditory stimuli presented from different locations in space based on the spatial position of the stimuli and the interstimulus delay (ISD) between the stimuli in a manner similar to humans. Cats exhibit localization dominance for pairs of transient stimuli with |ISDs| from ∼0.4 to 10 ms, summing localization for |ISDs| 10 ms, which is the appro...

  19. Fast 3D elastic micro-seismic source location using new GPU features

    Science.gov (United States)

    Xue, Qingfeng; Wang, Yibo; Chang, Xu

    2016-12-01

    In this paper, we describe new GPU features and their applications in passive seismic - micro-seismic location. Locating micro-seismic events is quite important in seismic exploration, especially when searching for unconventional oil and gas resources. Different from the traditional ray-based methods, the wave equation method, such as the method we use in our paper, has a remarkable advantage in adapting to low signal-to-noise ratio conditions and does not need a person to select the data. However, because it has a conspicuous deficiency due to its computation cost, these methods are not widely used in industrial fields. To make the method useful, we implement imaging-like wave equation micro-seismic location in a 3D elastic media and use GPU to accelerate our algorithm. We also introduce some new GPU features into the implementation to solve the data transfer and GPU utilization problems. Numerical and field data experiments show that our method can achieve a more than 30% performance improvement in GPU implementation just by using these new features.

  20. An acoustic vector based approach to locate low frequency noise sources in 3D

    NARCIS (Netherlands)

    Bree, H.-E. de; Ostendorf, C.; Basten, T.

    2009-01-01

    Although low frequency noise is an issue of huge societal importance, traditional acoustic testing methods have limitations in finding the low frequency source. It is hard to determine the direction of the noise using traditional microphones. Three dimensional sound probes capturing the particle

  1. A New Wave Equation Based Source Location Method with Full-waveform Inversion

    KAUST Repository

    Wu, Zedong; Alkhalifah, Tariq Ali

    2017-01-01

    with illumination artifacts. We develop a waveform inversion approach with an additional penalty term in the objective function to reward the focusing of the source image. This penalty term is relaxed early to allow for data fitting, and avoid cycle skipping, using

  2. Impacts of Reverberation Time, Absorption Location and Background Noise on Listening Conditions in Multi Source Environment

    DEFF Research Database (Denmark)

    Saher, Konca; Rindel, Jens Holger; Nijs, Lau

    2005-01-01

    index (STI) needs to be improved. The impact of the reverberation time (RT), the distribution of the absorptive materials and the introduction of a screen on STI are discussed briefly .However, these objective parameters have to be assessed through subjective judgement. Auralizations of the multi source...

  3. Locating People Diagnosed With HIV for Public Health Action: Utility of HIV Case Surveillance and Other Data Sources.

    Science.gov (United States)

    Padilla, Mabel; Mattson, Christine L; Scheer, Susan; Udeagu, Chi-Chi N; Buskin, Susan E; Hughes, Alison J; Jaenicke, Thomas; Wohl, Amy Rock; Prejean, Joseph; Wei, Stanley C

    Human immunodeficiency virus (HIV) case surveillance and other health care databases are increasingly being used for public health action, which has the potential to optimize the health outcomes of people living with HIV (PLWH). However, often PLWH cannot be located based on the contact information available in these data sources. We assessed the accuracy of contact information for PLWH in HIV case surveillance and additional data sources and whether time since diagnosis was associated with accurate contact information in HIV case surveillance and successful contact. The Case Surveillance-Based Sampling (CSBS) project was a pilot HIV surveillance system that selected a random population-based sample of people diagnosed with HIV from HIV case surveillance registries in 5 state and metropolitan areas. From November 2012 through June 2014, CSBS staff members attempted to locate and interview 1800 sampled people and used 22 data sources to search for contact information. Among 1063 contacted PLWH, HIV case surveillance data provided accurate telephone number, address, or HIV care facility information for 239 (22%), 412 (39%), and 827 (78%) sampled people, respectively. CSBS staff members used additional data sources, such as support services and commercial people-search databases, to locate and contact PLWH with insufficient contact information in HIV case surveillance. PLWH diagnosed surveillance than were PLWH diagnosed ≥1 year ago ( P = .002), and the benefit from using additional data sources was greater for PLWH with more longstanding HIV infection ( P surveillance cannot provide accurate contact information, health departments can prioritize searching additional data sources, especially for people with more longstanding HIV infection.

  4. Crowd-Sourced Mobility Mapping for Location Tracking Using Unlabeled Wi-Fi Simultaneous Localization and Mapping

    Directory of Open Access Journals (Sweden)

    Mu Zhou

    2015-01-01

    Full Text Available Due to the increasing requirements of the seamless and round-the-clock Location-based services (LBSs, a growing interest in Wi-Fi network aided location tracking is witnessed in the past decade. One of the significant problems of the conventional Wi-Fi location tracking approaches based on received signal strength (RSS fingerprinting is the time-consuming and labor intensive work involved in location fingerprint calibration. To solve this problem, a novel unlabeled Wi-Fi simultaneous localization and mapping (SLAM approach is developed to avoid the location fingerprinting and additional inertial or vision sensors. In this approach, an unlabeled mobility map of the coverage area is first constructed by using the crowd-sourcing from a batch of sporadically recorded Wi-Fi RSS sequences based on the spectral cluster assembling. Then, the sequence alignment algorithm is applied to conduct location tracking and mobility map updating. Finally, the effectiveness of this approach is verified by the extensive experiments carried out in a campus-wide area.

  5. Military Service Records and Unit Histories: A Guide to Locating Sources

    Science.gov (United States)

    2012-07-26

    records, therefoa- e , written authorization from the veta -an or ne.’Ct of kin is not rEqUired. However, in ordet" to protect the privacy of the...line E -mail: MPR.center@nara.gov Older military personnel records (generally prior to World War I, depending on the service branch) are located at...AFB, DC 20032-5000 E -mail: afhso.research@pentagon.af.mil http://www.afhso.af.mil/ (202) 404-2264 National Museum of the U.S. Air Force 1100

  6. A rotating modulation imager for locating mid-range point sources

    International Nuclear Information System (INIS)

    Kowash, B.R.; Wehe, D.K.; Fessler, J.A.

    2009-01-01

    Rotating modulation collimators (RMC) are relatively simple indirect imaging devices that have proven useful in gamma ray astronomy (far field) and have more recently been studied for medical imaging (very near field). At the University of Michigan a RMC has been built to study the performance for homeland security applications. This research highlights the imaging performance of this system and focuses on three distinct regions in the RMC field of view that can impact the search for hidden sources. These regions are a blind zone around the axis of rotation, a two mask image zone that extends from the blind zone to the edge of the field of view, and a single mask image zone that occurs when sources fall outside the field of view of both masks. By considering the extent and impact of these zones, the size of the two mask region can be optimized for the best system performance.

  7. Locating the Tohoku-Oki 2011 tsunami source using acoustic-gravity waves

    OpenAIRE

    Andriamiranto Raveloson; Rainer Kind; Xiaohui Yuan; L. Cerana

    2012-01-01

    The giant Tohoku-Oki earthquake of 11 March 2011 in offshore Japan did not only generate tsunami waves in the ocean but also infrasound (or acoustic-gravity) waves in the atmosphere. We indentified ultra-long-period signals (>500s) in the recordings of infrasound stations in northeast Asia, the northwest Pacific, and Alaska. Their source was fond close to the earthquake epicenter. Therefore, we conclude that in general, infrasound observations after a large offshore earthquake are evidence th...

  8. Source Apportionment of Particle Bound Polycyclic Aromatic Hydrocarbons at an Industrial Location in Agra, India

    Directory of Open Access Journals (Sweden)

    Anita Lakhani

    2012-01-01

    Full Text Available 16 US EPA priority polycyclic aromatic hydrocarbons (PAHs were quantified in total suspended ambient particulate matter (TSPM collected from an industrial site in Agra (India using gas chromatography. The major industrial activities in Agra are foundries that previously used coal and coke as fuel in cupola furnaces. These foundries have now switched over to natural gas. In addition, use of compressed natural gas has also been promoted and encouraged in automobiles. This study attempts to apportion sources of PAH in the ambient air and the results reflect the advantages associated with the change of fuel. The predominant PAHs in TSPM include high molecular weight (HMW congeners BghiP, DbA, IP, and BaP. The sum of 16 priority PAHs had a mean value of 72.7 ± 4.7 ng m−3. Potential sources of PAHs in aerosols were identified using diagnostic ratios and principal component analysis. The results reflect a blend of emissions from diesel and natural gas as the major sources of PAH in the city along with contribution from emission of coal, coke, and gasoline.

  9. Sources of Caffeine in Diets of US Children and Adults: Trends by Beverage Type and Purchase Location

    OpenAIRE

    Adam Drewnowski; Colin D. Rehm

    2016-01-01

    New sources of caffeine, besides coffee and tea, have been introduced into the US food supply. Data on caffeine consumption age and purchase location can help guide public health policy. National Health and Nutrition Examination Surveys (NHANES) were used to estimate population-level caffeine intakes, using data from 24-h dietary recall. First, caffeine intakes by age-group and beverage type were estimated using the most recent 2011?2012 data (n = 7456). Second, fourteen years trends in caffe...

  10. Locating single-point sources from arrival times containing large picking errors (LPEs): the virtual field optimization method (VFOM)

    Science.gov (United States)

    Li, Xi-Bing; Wang, Ze-Wei; Dong, Long-Jun

    2016-01-01

    Microseismic monitoring systems using local location techniques tend to be timely, automatic and stable. One basic requirement of these systems is the automatic picking of arrival times. However, arrival times generated by automated techniques always contain large picking errors (LPEs), which may make the location solution unreliable and cause the integrated system to be unstable. To overcome the LPE issue, we propose the virtual field optimization method (VFOM) for locating single-point sources. In contrast to existing approaches, the VFOM optimizes a continuous and virtually established objective function to search the space for the common intersection of the hyperboloids, which is determined by sensor pairs other than the least residual between the model-calculated and measured arrivals. The results of numerical examples and in-site blasts show that the VFOM can obtain more precise and stable solutions than traditional methods when the input data contain LPEs. Furthermore, we discuss the impact of LPEs on objective functions to determine the LPE-tolerant mechanism, velocity sensitivity and stopping criteria of the VFOM. The proposed method is also capable of locating acoustic sources using passive techniques such as passive sonar detection and acoustic emission.

  11. Source locations for impulsive electric signals seen in the night ionosphere of Venus

    Science.gov (United States)

    Russell, C. T.; Von Dornum, M.; Scarf, F. L.

    1989-01-01

    A mapping of the rate of occurrence of impulsive VLF noise bursts in Venus' dark low altitude ionosphere, which increases rapidly with decreasing altitude, as a function of latitude and longitude indicates enhanced occurrence rates over Atla. In a 30-sec observing period, there are impulsive signals 70 percent of the time at 160 km in the region of maximum occurrence; the occurrence rates, moreover, increase with decreasing latitude, so that the equatorial rate is of the order of 1.6 times that at 30 deg latitude. These phenomena are in keeping with lightning-generated wave sources.

  12. Waveform inversion of lateral velocity variation from wavefield source location perturbation

    KAUST Repository

    Choi, Yun Seok

    2013-09-22

    It is challenge in waveform inversion to precisely define the deep part of the velocity model compared to the shallow part. The lateral velocity variation, or what referred to as the derivative of velocity with respect to the horizontal distance, with well log data can be used to update the deep part of the velocity model more precisely. We develop a waveform inversion algorithm to obtain the lateral velocity variation by inverting the wavefield variation associated with the lateral shot location perturbation. The gradient of the new waveform inversion algorithm is obtained by the adjoint-state method. Our inversion algorithm focuses on resolving the lateral changes of the velocity model with respect to a fixed reference vertical velocity profile given by a well log. We apply the method on a simple-dome model to highlight the methods potential.

  13. Metamaterials-based sensor to detect and locate nonlinear elastic sources

    Energy Technology Data Exchange (ETDEWEB)

    Gliozzi, Antonio S.; Scalerandi, Marco [Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino (Italy); Miniaci, Marco; Bosia, Federico [Department of Physics, University of Torino, Via Pietro Giuria 1, 10125 Torino (Italy); Pugno, Nicola M. [Laboratory of Bio-Inspired and Graphene Nanomechanics, Department of Civil, Environmental and Mechanical Engineering, University of Trento, Via Mesiano 77, 38123 Trento (Italy); Center for Materials and Microsystems, Fondazione Bruno Kessler, Via Sommarive 18, 38123 Povo (Trento) (Italy); School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London E1 4NS (United Kingdom)

    2015-10-19

    In recent years, acoustic metamaterials have attracted increasing scientific interest for very diverse technological applications ranging from sound abatement to ultrasonic imaging, mainly due to their ability to act as band-stop filters. At the same time, the concept of chaotic cavities has been recently proposed as an efficient tool to enhance the quality of nonlinear signal analysis, particularly in the ultrasonic/acoustic case. The goal of the present paper is to merge the two concepts in order to propose a metamaterial-based device that can be used as a natural and selective linear filter for the detection of signals resulting from the propagation of elastic waves in nonlinear materials, e.g., in the presence of damage, and as a detector for the damage itself in time reversal experiments. Numerical simulations demonstrate the feasibility of the approach and the potential of the device in providing improved signal-to-noise ratios and enhanced focusing on the defect locations.

  14. Metamaterials-based sensor to detect and locate nonlinear elastic sources

    International Nuclear Information System (INIS)

    Gliozzi, Antonio S.; Scalerandi, Marco; Miniaci, Marco; Bosia, Federico; Pugno, Nicola M.

    2015-01-01

    In recent years, acoustic metamaterials have attracted increasing scientific interest for very diverse technological applications ranging from sound abatement to ultrasonic imaging, mainly due to their ability to act as band-stop filters. At the same time, the concept of chaotic cavities has been recently proposed as an efficient tool to enhance the quality of nonlinear signal analysis, particularly in the ultrasonic/acoustic case. The goal of the present paper is to merge the two concepts in order to propose a metamaterial-based device that can be used as a natural and selective linear filter for the detection of signals resulting from the propagation of elastic waves in nonlinear materials, e.g., in the presence of damage, and as a detector for the damage itself in time reversal experiments. Numerical simulations demonstrate the feasibility of the approach and the potential of the device in providing improved signal-to-noise ratios and enhanced focusing on the defect locations

  15. Toward morphological thoracic EIT: major signal sources correspond to respective organ locations in CT.

    Science.gov (United States)

    Ferrario, Damien; Grychtol, Bartłomiej; Adler, Andy; Solà, Josep; Böhm, Stephan H; Bodenstein, Marc

    2012-11-01

    Lung and cardiovascular monitoring applications of electrical impedance tomography (EIT) require localization of relevant functional structures or organs of interest within the reconstructed images. We describe an algorithm for automatic detection of heart and lung regions in a time series of EIT images. Using EIT reconstruction based on anatomical models, candidate regions are identified in the frequency domain and image-based classification techniques applied. The algorithm was validated on a set of simultaneously recorded EIT and CT data in pigs. In all cases, identified regions in EIT images corresponded to those manually segmented in the matched CT image. Results demonstrate the ability of EIT technology to reconstruct relevant impedance changes at their anatomical locations, provided that information about the thoracic boundary shape (and electrode positions) are used for reconstruction.

  16. Critical Node Location in De Bruijn Networks

    Science.gov (United States)

    2016-10-01

    algorithms that are normally time- consuming perform exceptionally well on de Bruijn networks. This class of networks has yet to be considered from an...tolerant networks, peer-to-peer networks, amongst others. Because of their unique properties, many algorithms that are normally time- consuming perform...a quadratic binary equation, each higher order term must be replaced with several new variables. While this is possible, it is a time- consuming and

  17. Accuracy evaluation of distance inverse square law in determining virtual electron source location in Siemens Primus linac.

    Science.gov (United States)

    Douk, Hamid Shafaei; Aghamiri, Mahmoud Reza; Ghorbani, Mahdi; Farhood, Bagher; Bakhshandeh, Mohsen; Hemmati, Hamid Reza

    2018-01-01

    The aim of this study is to evaluate the accuracy of the inverse square law (ISL) method for determining location of virtual electron source ( S Vir ) in Siemens Primus linac. So far, different experimental methods have presented for determining virtual and effective electron source location such as Full Width at Half Maximum (FWHM), Multiple Coulomb Scattering (MCS), and Multi Pinhole Camera (MPC) and Inverse Square Law (ISL) methods. Among these methods, Inverse Square Law is the most common used method. Firstly, Siemens Primus linac was simulated using MCNPX Monte Carlo code. Then, by using dose profiles obtained from the Monte Carlo simulations, the location of S Vir was calculated for 5, 7, 8, 10, 12 and 14 MeV electron energies and 10 cm × 10 cm, 15 cm × 15 cm, 20 cm × 20 cm and 25 cm × 25 cm field sizes. Additionally, the location of S Vir was obtained by the ISL method for the mentioned electron energies and field sizes. Finally, the values obtained by the ISL method were compared to the values resulted from Monte Carlo simulation. The findings indicate that the calculated S Vir values depend on beam energy and field size. For a specific energy, with increase of field size, the distance of S Vir increases for most cases. Furthermore, for a special applicator, with increase of electron energy, the distance of S Vir increases for most cases. The variation of S Vir values versus change of field size in a certain energy is more than the variation of S Vir values versus change of electron energy in a certain field size. According to the results, it is concluded that the ISL method can be considered as a good method for calculation of S Vir location in higher electron energies (14 MeV).

  18. Seismic swarm associated with the 2008 eruption of Kasatochi Volcano, Alaska: earthquake locations and source parameters

    Science.gov (United States)

    Ruppert, Natalia G.; Prejean, Stephanie G.; Hansen, Roger A.

    2011-01-01

    An energetic seismic swarm accompanied an eruption of Kasatochi Volcano in the central Aleutian volcanic arc in August of 2008. In retrospect, the first earthquakes in the swarm were detected about 1 month prior to the eruption onset. Activity in the swarm quickly intensified less than 48 h prior to the first large explosion and subsequently subsided with decline of eruptive activity. The largest earthquake measured as moment magnitude 5.8, and a dozen additional earthquakes were larger than magnitude 4. The swarm exhibited both tectonic and volcanic characteristics. Its shear failure earthquake features were b value = 0.9, most earthquakes with impulsive P and S arrivals and higher-frequency content, and earthquake faulting parameters consistent with regional tectonic stresses. Its volcanic or fluid-influenced seismicity features were volcanic tremor, large CLVD components in moment tensor solutions, and increasing magnitudes with time. Earthquake location tests suggest that the earthquakes occurred in a distributed volume elongated in the NS direction either directly under the volcano or within 5-10 km south of it. Following the MW 5.8 event, earthquakes occurred in a new crustal volume slightly east and north of the previous earthquakes. The central Aleutian Arc is a tectonically active region with seismicity occurring in the crusts of the Pacific and North American plates in addition to interplate events. We postulate that the Kasatochi seismic swarm was a manifestation of the complex interaction of tectonic and magmatic processes in the Earth's crust. Although magmatic intrusion triggered the earthquakes in the swarm, the earthquakes failed in context of the regional stress field.

  19. Characterizing and locating air pollution sources in a complex industrial district using optical remote sensing technology and multivariate statistical modeling.

    Science.gov (United States)

    Chang, Pao-Erh Paul; Yang, Jen-Chih Rena; Den, Walter; Wu, Chang-Fu

    2014-09-01

    Emissions of volatile organic compounds (VOCs) are most frequent environmental nuisance complaints in urban areas, especially where industrial districts are nearby. Unfortunately, identifying the responsible emission sources of VOCs is essentially a difficult task. In this study, we proposed a dynamic approach to gradually confine the location of potential VOC emission sources in an industrial complex, by combining multi-path open-path Fourier transform infrared spectrometry (OP-FTIR) measurement and the statistical method of principal component analysis (PCA). Close-cell FTIR was further used to verify the VOC emission source by measuring emitted VOCs from selected exhaust stacks at factories in the confined areas. Multiple open-path monitoring lines were deployed during a 3-month monitoring campaign in a complex industrial district. The emission patterns were identified and locations of emissions were confined by the wind data collected simultaneously. N,N-Dimethyl formamide (DMF), 2-butanone, toluene, and ethyl acetate with mean concentrations of 80.0 ± 1.8, 34.5 ± 0.8, 103.7 ± 2.8, and 26.6 ± 0.7 ppbv, respectively, were identified as the major VOC mixture at all times of the day around the receptor site. As the toxic air pollutant, the concentrations of DMF in air samples were found exceeding the ambient standard despite the path-average effect of OP-FTIR upon concentration levels. The PCA data identified three major emission sources, including PU coating, chemical packaging, and lithographic printing industries. Applying instrumental measurement and statistical modeling, this study has established a systematic approach for locating emission sources. Statistical modeling (PCA) plays an important role in reducing dimensionality of a large measured dataset and identifying underlying emission sources. Instrumental measurement, however, helps verify the outcomes of the statistical modeling. The field study has demonstrated the feasibility of

  20. Assessment of environmental gamma radiation levels at locations having different source characteristics using TLDs

    International Nuclear Information System (INIS)

    Sahu, S.K.; Swarnkar, M.; Takale, R.A.; Shetty, P.G.; Pandit, G.G.; Puranik, V.D.

    2012-01-01

    Naturally occurring radionuclides are the major contributor to the total effective dose of ionizing radiation received by the population (UNSCEAR, 1993). The dose in environment thus depends largely on natural radiation than manmade or artificially produced radiation. In the last few decades, there is a growing concern all over the world about radiation and their exposure to population. Thus, it is a necessity to conduct frequent radiological environmental surveillance in order to assess population exposure accurately. Recently, application of thermoluminescence dosimeters (TLDs) has been extended to the measurement of mixed radiation field as encountered in the environment. The advantages of passive TL dosimeters for environmental monitoring are that they are small, cheap and do not require power supply during application. The passive TL dosimeters play an important role to provide data on natural background radiation and to determine the contribution to the dose to public from man-made sources. In the present study, three different sites were chosen to compare environmental gamma radiation levels in different scenarios. Kaiga has been chosen as site 1, where four unit of pressurized heavy water reactor (PHWR) of 220 MWe each are in operation. Site 2 is chosen at natural high background radiation area (NHBRA) of Kerala and Vishakhapatnam was chosen as site 3, which is situated at a normal background area. The objective of the study is to illustrate the effect, if any, of an operating nuclear power reactor on environmental gamma radiation levels

  1. Plasma assisted growth of MoO{sub 3} films on different substrate locations relative to sublimation source

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Rabindar K., E-mail: rkrksharma6@gmail.com; Saini, Sujit K.; Kumar, Prabhat; Singh, Megha; Reddy, G. B. [Thin film laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi – 110016 (India)

    2016-05-06

    In the present paper, we reported the role of substrate locations relative to source on the growth of MoO{sub 3} films deposited on Ni coated glass substrates using plasma assisted sublimation process (PASP). According to the XRD and SEM results, substrate location is very crucial factor to control the morphology of MoO{sub 3} films and the best nanostructure growth (in terms of alignments and features) is obtained in case of Sample B (in which substrate is placed on source). The structural results point out that all films exhibit only orthorhombic phase of molybdenum oxide (i.e. α-MoO{sub 3})but the most preferential growth is recorded in Sample B due to the presence of intense peaks crossponding to only (0 k 0) family of crystal planes (k = 2, 4,6..). The Raman analysis again confirms the orthorhombic nature of MoO{sub 3} NFs and details of vibrational bondsin Sample B have been given in the present report. The MoO{sub 3} NFs show intense PL emission in wavelength range of 300-700 nm with three peaks located at 415, 490, and 523 nm in accordance to the improved crystallinity in Sample B.

  2. Energy based source location by using acoustic emission for damage detection in steel and composite CNG tank

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Il Sik; Han, Byeong Hee; Park, Choon Su; Yoon, Dong Jin [Center for Safety Measurements, Korea Research Institute of Standards and Science, Daejeon (Korea, Republic of)

    2015-10-15

    Acoustic emission (AE) is an effective nondestructive test that uses transient elastic wave generated by the rapid release of energy within a material to detect any further growth or expansion of existing defects. Over the past decades, because of environmental issues, the use of compressed natural gas (CNG) as an alternative fuel for vehicles is increasing because of environmental issues. For this reason, the importance and necessity of detecting defects on a CNG fuel tank has also come to the fore. The conventional AE method used for source location is highly affected by the wave speed on the structure, and this creates problems in inspecting a composite CNG fuel tank. Because the speed and dispersion characteristics of the wave are different according to direction of structure and laminated layers. In this study, both the conventional AE method and the energy based contour map method were used for source location. This new method based on pre-acquired D/B was used for overcoming the limitation of damage localization in a composite CNG fuel tank specimen which consists of a steel liner cylinder overwrapped by GFRP. From the experimental results, it is observed that the damage localization is determined with a small error at all tested points by using the energy based contour map method, while there were a number of mis-locations or large errors at many tested points by using the conventional AE method. Therefore, the energy based contour map method used in this work is more suitable technology for inspecting composite structures.

  3. Comparing brain graphs in which nodes are regions of interest or independent components: A simulation study.

    Science.gov (United States)

    Yu, Qingbao; Du, Yuhui; Chen, Jiayu; He, Hao; Sui, Jing; Pearlson, Godfrey; Calhoun, Vince D

    2017-11-01

    A key challenge in building a brain graph using fMRI data is how to define the nodes. Spatial brain components estimated by independent components analysis (ICA) and regions of interest (ROIs) determined by brain atlas are two popular methods to define nodes in brain graphs. It is difficult to evaluate which method is better in real fMRI data. Here we perform a simulation study and evaluate the accuracies of a few graph metrics in graphs with nodes of ICA components, ROIs, or modified ROIs in four simulation scenarios. Graph measures with ICA nodes are more accurate than graphs with ROI nodes in all cases. Graph measures with modified ROI nodes are modulated by artifacts. The correlations of graph metrics across subjects between graphs with ICA nodes and ground truth are higher than the correlations between graphs with ROI nodes and ground truth in scenarios with large overlapped spatial sources. Moreover, moving the location of ROIs would largely decrease the correlations in all scenarios. Evaluating graphs with different nodes is promising in simulated data rather than real data because different scenarios can be simulated and measures of different graphs can be compared with a known ground truth. Since ROIs defined using brain atlas may not correspond well to real functional boundaries, overall findings of this work suggest that it is more appropriate to define nodes using data-driven ICA than ROI approaches in real fMRI data. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Fuel from Wastewater - Harnessing a Potential Energy Source in Canada through the Co-location of Algae Biofuel Production to Sources of Effluent, Heat and CO2

    Science.gov (United States)

    Klise, G. T.; Roach, J. D.; Passell, H. D.; Moreland, B. D.; O'Leary, S. J.; Pienkos, P. T.; Whalen, J.

    2010-12-01

    Sandia National Laboratories is collaborating with the National Research Council (NRC) Canada and the National Renewable Energy Laboratory (NREL) to develop a decision-support model that will evaluate the tradeoffs associated with high-latitude algae biofuel production co-located with wastewater, CO2, and waste heat. This project helps Canada meet its goal of diversifying fuel sources with algae-based biofuels. The biofuel production will provide a wide range of benefits including wastewater treatment, CO2 reuse and reduction of demand for fossil-based fuels. The higher energy density in algae-based fuels gives them an advantage over crop-based biofuels as the “production” footprint required is much less, resulting in less water consumed and little, if any conversion of agricultural land from food to fuel production. Besides being a potential source for liquid fuel, algae have the potential to be used to generate electricity through the burning of dried biomass, or anaerobically digested to generate methane for electricity production. Co-locating algae production with waste streams may be crucial for making algae an economically valuable fuel source, and will certainly improve its overall ecological sustainability. The modeling process will address these questions, and others that are important to the use of water for energy production: What are the locations where all resources are co-located, and what volumes of algal biomass and oil can be produced there? In locations where co-location does not occur, what resources should be transported, and how far, while maintaining economic viability? This work is being funded through the U.S. Department of Energy (DOE) Biomass Program Office of Energy Efficiency and Renewable Energy, and is part of a larger collaborative effort that includes sampling, strain isolation, strain characterization and cultivation being performed by the NREL and Canada’s NRC. Results from the NREL / NRC collaboration including specific

  5. Shifting primary energy source and NOx emission location with plug-in hybrid vehicles

    Science.gov (United States)

    Karman, Deniz

    2011-06-01

    Plug-in hybrid vehicles (PHEVs) present an interesting technological opportunity for using non-fossil primary energy in light duty passenger vehicles, with the associated potential for reducing air pollutant and greenhouse gas emissions, to the extent that the electric power grid is fed by non-fossil sources. This perspective, accompanying the article by Thompson et al (2011) in this issue, will touch on two other studies that are directly related: the Argonne study (Elgowainy et al 2010) and a PhD thesis from Utrecht (van Vliet 2010). Thompson et al (2011) have examined air quality effects in a case where the grid is predominantly fossil fed. They estimate a reduction of 7.42 tons/day of NOx from motor vehicles as a result of substituting electric VMTs for 20% of the light duty gasoline vehicle miles traveled. To estimate the impact of this reduction on air quality they also consider the increases in NOx emissions due to the increased load on electricity generating units. The NOx emission increases are estimated as 4.0, 5.5 and 6.3 tons for the Convenience, Battery and Night charging scenarios respectively. The net reductions are thus in the 1.1-3.4 tons/day range. The air quality modelling results presented show that the air quality impact from a ground-level ozone perspective is favorable overall, and while the effect is stronger in some localities, the difference between the three scenarios is small. This is quite significant and suggests that localization of the NOx emissions to point sources has a more pronounced effect than the absolute reductions achieved. Furthermore it demonstrates that localization of NOx emissions to electricity generating units by using PHEVs in vehicle traffic has beneficial effects for air quality not only by minimizing direct human exposure to motor vehicle emissions, but also due to reduced exposure to secondary pollutants (i.e. ozone). In an electric power grid with a smaller share of fossil fired generating units, the beneficial

  6. Pattern of Colon Cancer Lymph Node Metastases in Patients Undergoing Central Mesocolic Lymph Node Excision

    DEFF Research Database (Denmark)

    Bertelsen, Claus A; Kirkegaard-Klitbo, Anders; Nielsen, Mingyuan

    2016-01-01

    BACKGROUND: Extended mesocolic lymph node dissection in colon cancer surgery seems to improve oncological outcome. A possible reason might be related to metastases in the central mesocolic lymph nodes. OBJECTIVE: The purpose of this study was to describe the pattern of mesocolic lymph node...... metastases, particularly in central lymph nodes, and the risk of skip, aberrant, and gastrocolic ligament metastases as the argument for performing extended lymph node dissection. DATA SOURCES: EMBASE and PubMed were searched using the terms colon or colorectal with sentinel node, lymph node mapping, or skip...... node; lymph node resection colon; and complete or total and mesocolic excision. STUDY SELECTION: Studies describing the risk of metastases in central, skip, aberrant, and gastrocolic ligament lymph node metastases from colon adenocarcinomas in 10 or more patients were included. No languages were...

  7. Two Simon tasks with different sources of conflict: an ERP study of motion- and location-based compatibility effects.

    Science.gov (United States)

    Galashan, Daniela; Wittfoth, Matthias; Fehr, Thorsten; Herrmann, Manfred

    2008-07-01

    Behavioral and electrophysiological correlates of two Simon tasks were examined using comparable stimuli but different task-irrelevant and conflict-inducing stimulus features. Whereas target shape was always the task-relevant stimulus attribute, either target location (location-based task) or motion direction within the target stimuli (motion-based task) was used as a source of conflict. Data from ten healthy participants who performed both tasks are presented. In the motion-based task the incompatible condition showed smaller P300 amplitudes at Pz than the compatible condition and the location-based task yielded a trend towards a reduced P300 amplitude in the incompatible condition. For both tasks, no P300 latency differences between the conditions were found at Pz. The results suggest that the motion-based task elicits behavioral and electrophysiological effects comparable with regular Simon tasks. As all stimuli in the motion-based Simon task were presented centrally the present data strongly argue against the attention-shifting account as an explanatory approach.

  8. Consumption of added sugars among US children and adults by food purchase location and food source123

    Science.gov (United States)

    Drewnowski, Adam; Rehm, Colin D

    2014-01-01

    Background: The proposed changes to the Nutrition Facts Label by the US Food and Drug Administration will include information on added sugars for the first time. Objective: The objective was to evaluate the sources of added sugars in the diets of a representative sample of US children and adults by food purchase location and food source (eg, food group). Design: This cross-sectional study among 31,035 children, adolescents, and adults aged ≥6 y from the 2003–2004, 2005–2006, 2007–2008, and 2009–2010 NHANES used data from a 24-h dietary recall to evaluate consumption of added sugars. Food locations of origin were identified as stores (supermarket or grocery store), quick-service restaurants/pizza (QSRs), full-service restaurants (FSRs), schools, and others (eg, vending machines or gifts). Added sugars consumption by food purchase location was evaluated by age, family income-to-poverty ratio, and race-ethnicity. Food group sources of added sugars were identified by using the National Cancer Institute food categories. Results: Added sugars accounted for ∼14.1% of total dietary energy. Between 65% and 76% of added sugars came from stores, 6% and 12% from QSRs, and 4% and 6% from FSRs, depending on age. Older adults (aged ≥51 y) obtained a significantly greater proportion of added sugars from stores than did younger adults. Lower-income adults obtained a significantly greater proportion of added sugars from stores than did higher-income adults. Intake of added sugars did not vary by family income among children/adolescents. Soda and energy and sports drinks were the largest food group sources of added sugars (34.4%), followed by grain desserts (12.7%), fruit drinks (8.0%), candy (6.7%), and dairy desserts (5.6%). Conclusions: Most added sugars came from foods obtained from stores. The proposed changes to the Nutrition Facts Label should capture the bulk of added sugars in the US food supply, which suggests that the recommended changes have the potential to

  9. Sodium intakes of US children and adults from foods and beverages by location of origin and by specific food source.

    Science.gov (United States)

    Drewnowski, Adam; Rehm, Colin D

    2013-05-28

    Sodium intakes, from foods and beverages, of 22,852 persons in the National Health and Nutrition Examination Surveys (NHANES 2003-2008) were examined by specific food source and by food location of origin. Analyses were based on a single 24-h recall. Separate analyses were conducted for children (6-11 years of age), adolescents (12-19), and adults (20-50 and ≥51 years). Grouping of like foods (e.g., food sources) used a scheme proposed by the National Cancer Institute, which divides foods/beverages into 96 food subgroups (e.g., pizza, yeast breads or cold cuts). Food locations of origin were stores (e.g., grocery, convenience and specialty stores), quick-service restaurant/pizza (QSR), full-service restaurant (FSR), school, or other. Food locations of sodium were also evaluated by race/ethnicity amongst adults. Stores provided between 58.1% and 65.2% of dietary sodium, whereas QSR and FSR together provided between 18.9% and 31.8% depending on age. The proportion of sodium from QSR varied from 10.1% to 19.9%, whereas that from FSR varied from 3.4% to 13.3%. School meals provided 10.4% of sodium for 6-11 year olds and 6.0% for 12-19 year olds. Pizza from QSR, the top away from home food item, provided 5.4% of sodium in adolescents. QSR pizza, chicken, burgers and Mexican dishes combined provided 7.8% of total sodium in adult diets. Most sodium came from foods purchased in stores. Food manufacturers, restaurants, and grocery stores all have a role to play in reducing the amount of sodium in the American diet.

  10. Location of terminals in a communications network

    DEFF Research Database (Denmark)

    2015-01-01

    A method (400, 500) of identifying nodes in a communications network is disclosed, the nodes being for use in locating wireless terminals within the network based upon reports from the wireless terminals of transmissions received from the nodes. The method (400, 500) comprises prioritising...... combinations of nodes in which at least three nodes are located around a reference node in a configuration satisfying similarity criteria to an idealised star configuration, wherein an idealised star configuration comprises three nodes evenly angularly distributed around, and at the same distance from......, a reference node. Also disclosed is a method (100, 200) for locating a plurality of wireless terminals in a communications network, the network comprising a plurality of network nodes at known locations, wherein the nodes emit wireless transmissions in an unsynchronised manner, such that a time difference...

  11. Oil pollution and microbiological quality of groundwater at the location of the water source 'Ratno ostrvo' nearby Novi Sad

    International Nuclear Information System (INIS)

    Petrovic, O.; Simeunovic, J.; Radnovic, D.; Matavulj, M.; Gajin, S.

    2002-01-01

    The 'Ratno ostrvo' is the biggest drinking water source in wider area of Novi Sad. It is located on the left bank of the river Danube near the Oil Refinery 'Novi Sad'. One of the consequences of the NATO bombing of the Oil Refinery 'Novi Sad' (which is placed in hinterland of the water source) was the uncontrolled spillage of crude oil and oil derivatives. Because of that, microbiological examinations of groundwaters, from both ecological and sanitary aspects were carried out simultaneously during post-war period. Microbiological analyses from sanitary aspects show very low number of coliform bacteria. Determination of numbers of bacteria of the investigated physiological groups, revealed that there was a constant relatively high number of oil-, phenol oxidizing and lipolytic bacteria which are indicators this kind of specific pollution. Microbiological analysis of oil polluted soil show presence relatively high number of different groups of bacteria. In spite of changed ecological situation caused by war effects, microbiological analyses of groundwater quality showed satisfactory results in source 'Ratno ostrvo' by now. The presence and potential activity of indigenous microflora could be utilized in recultivation processes in examined area. (author)

  12. Penile lymphoscintigraphy for sentinel node identification

    International Nuclear Information System (INIS)

    Valdes Olmos, R.A.; Hoefnagel, C.A.; Tanis, P.J.; Jansen, L.; Nieweg, O.E.; Meinhardt, W.; Horenblas, S.

    2001-01-01

    Lymphoscintigraphy for sentinel node (SN) identification has been extensively validated in breast cancer and melanoma. The aim of this study was to evaluate the findings of lymphoscintigraphy for SN identification in carcinoma of the penis. Lymphoscintigraphy was performed in 74 consecutive patients (mean age 62.2 years, range 28-87 years) with clinically lymph node-negative squamous cell carcinoma of the penis (stage T2 or greater). Following local anaesthesia by xy-locaine 10% spray, technetium-99m nanocolloid (mean dose 64.8 MBq, range 40-131 MBq) in a volume of 0.3-0.4 ml was injected intradermally around the tumour. Shortly after injection, a 20-min dynamic study was performed with a dual-head gamma camera; subsequently, static anterior and lateral images were obtained at 30 min and 2 h using simultaneous cobalt-57 flood source transmission scanning. 57 Co-assisted skin marking defined SN location for gamma probe/blue dye-guided biopsy, which was performed the next day. The SN visualization rate was 97% (72/74). Lymphatic drainage was bilateral in 81% of the cases (58/72), exclusively to the left groin in 13% (9/72) and only to the right groin in 6%. Bilateral lymph node drainage was synchronous in 38% (22/58) and asynchronous in 62% (in 18 patients the initial route was the left groin, and in the other 18, the right groin). Visualization before 30 min occurred in 66 patients (93%), in 64 of them (88%) already during the dynamic study. A total of 173 SNs were visualized (85 in the right groin, 88 in the left groin). Pitfalls were caused by inguinal skin contamination during injection (four patients) and intracavernous administration (one patient). At surgery, a total of 161 SNs were identified and removed. Sixteen patients (22%) had a tumour-positive SN and underwent standard regional lymph node dissection subsequently. During follow-up (median 28 months, range 3-74 months), two patients with a negative SN developed lymph node metastases in the mapped basin

  13. Penile lymphoscintigraphy for sentinel node identification

    Energy Technology Data Exchange (ETDEWEB)

    Valdes Olmos, R.A.; Hoefnagel, C.A. [Netherlands Cancer Inst., Amsterdam (Netherlands). Dept. of Nuclear Medicine; Tanis, P.J.; Jansen, L.; Nieweg, O.E. [Netherlands Cancer Inst., Amsterdam (Netherlands). Dept. of Surgery; Meinhardt, W.; Horenblas, S. [Netherlands Cancer Inst., Amsterdam (Netherlands). Dept. of Urology

    2001-05-01

    Lymphoscintigraphy for sentinel node (SN) identification has been extensively validated in breast cancer and melanoma. The aim of this study was to evaluate the findings of lymphoscintigraphy for SN identification in carcinoma of the penis. Lymphoscintigraphy was performed in 74 consecutive patients (mean age 62.2 years, range 28-87 years) with clinically lymph node-negative squamous cell carcinoma of the penis (stage T2 or greater). Following local anaesthesia by xy-locaine 10% spray, technetium-99m nanocolloid (mean dose 64.8 MBq, range 40-131 MBq) in a volume of 0.3-0.4 ml was injected intradermally around the tumour. Shortly after injection, a 20-min dynamic study was performed with a dual-head gamma camera; subsequently, static anterior and lateral images were obtained at 30 min and 2 h using simultaneous cobalt-57 flood source transmission scanning. {sup 57}Co-assisted skin marking defined SN location for gamma probe/blue dye-guided biopsy, which was performed the next day. The SN visualization rate was 97% (72/74). Lymphatic drainage was bilateral in 81% of the cases (58/72), exclusively to the left groin in 13% (9/72) and only to the right groin in 6%. Bilateral lymph node drainage was synchronous in 38% (22/58) and asynchronous in 62% (in 18 patients the initial route was the left groin, and in the other 18, the right groin). Visualization before 30 min occurred in 66 patients (93%), in 64 of them (88%) already during the dynamic study. A total of 173 SNs were visualized (85 in the right groin, 88 in the left groin). Pitfalls were caused by inguinal skin contamination during injection (four patients) and intracavernous administration (one patient). At surgery, a total of 161 SNs were identified and removed. Sixteen patients (22%) had a tumour-positive SN and underwent standard regional lymph node dissection subsequently. During follow-up (median 28 months, range 3-74 months), two patients with a negative SN developed lymph node metastases in the mapped

  14. Source contributions to PM2.5 and PM10 at an urban background and a street location

    Science.gov (United States)

    Keuken, M. P.; Moerman, M.; Voogt, M.; Blom, M.; Weijers, E. P.; Röckmann, T.; Dusek, U.

    2013-06-01

    The contribution of regional, urban and traffic sources to PM2.5 and PM10 in an urban area was investigated in this study. The chemical composition of PM2.5 and PM10 was measured over a year at a street location and up- and down-wind of the city of Rotterdam, the Netherlands. The 14C content in EC and OC concentrations was also determined, to distinguish the contribution from "modern" carbon (e.g., biogenic emissions, biomass burning and wildfires) and fossil fuel combustion. It was concluded that the urban background of PM2.5 and PM10 is dominated by the regional background, and that primary and secondary PM emission by urban sources contribute less than 15%. The 14C analysis revealed that 70% of OC originates from modern carbon and 30% from fossil fuel combustion. The corresponding percentages for EC are, respectively 17% and 83%. It is concluded that in particular the urban population living in street canyons with intense road traffic has potential health risks. This is due to exposure to elevated concentrations of a factor two for EC from exhaust emissions in PM2.5 and a factor 2-3 for heavy metals from brake and tyre wear, and re-suspended road dust in PM10. It follows that local air quality management may focus on local measures to street canyons with intense road traffic.

  15. Smart Home Wireless Sensor Nodes

    DEFF Research Database (Denmark)

    Lynggaard, Per

    . This paper introduces an approach that considerably lowers the wireless sensor node power consumption and the amount of transmitted sensor events. It uses smart objects that include artificial intelligence to efficiently process the sensor event on location and thereby saves the costly wireless...

  16. Sources of Caffeine in Diets of US Children and Adults: Trends by Beverage Type and Purchase Location

    Science.gov (United States)

    Drewnowski, Adam; Rehm, Colin D.

    2016-01-01

    New sources of caffeine, besides coffee and tea, have been introduced into the US food supply. Data on caffeine consumption age and purchase location can help guide public health policy. National Health and Nutrition Examination Surveys (NHANES) were used to estimate population-level caffeine intakes, using data from 24-h dietary recall. First, caffeine intakes by age-group and beverage type were estimated using the most recent 2011–2012 data (n = 7456). Second, fourteen years trends in caffeine consumption, overall and by beverage type, were evaluated for adults and children. Trend analyses were conducted by age groups. Last, trends in caffeine intakes by purchase location and beverage type were estimated. In 2011–2012, children aged four to eight years consumed the least caffeine (15 mg/day), and adults aged 51–70 years consumed the most (213 mg/day). The population mean (age ≥ four years) was 135 mg/day, driven largely by coffee (90 mg/day), tea (25 mg/day), and soda (21 mg/day). For the 14–19 years and 20–34 years age-groups, energy drinks contributed 6 mg/day (9.9%) and 5 mg/day (4.5%), respectively. The bulk of caffeine came from store-bought coffee and tea. Among both children and adults combined, caffeine intakes declined from 175 mg/day (1999–2000) to 142 mg/day (2011–2012), largely driven by a drop in caffeine from soda (41 mg/day to 21 mg/day). Store-bought coffee and tea remain principal drivers of caffeine intake in the US. Sodas and energy drinks make minor contributions to overall caffeine intakes. PMID:26978391

  17. Sources of Caffeine in Diets of US Children and Adults: Trends by Beverage Type and Purchase Location.

    Science.gov (United States)

    Drewnowski, Adam; Rehm, Colin D

    2016-03-10

    New sources of caffeine, besides coffee and tea, have been introduced into the US food supply. Data on caffeine consumption age and purchase location can help guide public health policy. National Health and Nutrition Examination Surveys (NHANES) were used to estimate population-level caffeine intakes, using data from 24-h dietary recall. First, caffeine intakes by age-group and beverage type were estimated using the most recent 2011-2012 data (n = 7456). Second, fourteen years trends in caffeine consumption, overall and by beverage type, were evaluated for adults and children. Trend analyses were conducted by age groups. Last, trends in caffeine intakes by purchase location and beverage type were estimated. In 2011-2012, children aged four to eight years consumed the least caffeine (15 mg/day), and adults aged 51-70 years consumed the most (213 mg/day). The population mean (age ≥ four years) was 135 mg/day, driven largely by coffee (90 mg/day), tea (25 mg/day), and soda (21 mg/day). For the 14-19 years and 20-34 years age-groups, energy drinks contributed 6 mg/day (9.9%) and 5 mg/day (4.5%), respectively. The bulk of caffeine came from store-bought coffee and tea. Among both children and adults combined, caffeine intakes declined from 175 mg/day (1999-2000) to 142 mg/day (2011-2012), largely driven by a drop in caffeine from soda (41 mg/day to 21 mg/day). Store-bought coffee and tea remain principal drivers of caffeine intake in the US. Sodas and energy drinks make minor contributions to overall caffeine intakes.

  18. Sources of Caffeine in Diets of US Children and Adults: Trends by Beverage Type and Purchase Location

    Directory of Open Access Journals (Sweden)

    Adam Drewnowski

    2016-03-01

    Full Text Available New sources of caffeine, besides coffee and tea, have been introduced into the US food supply. Data on caffeine consumption age and purchase location can help guide public health policy. National Health and Nutrition Examination Surveys (NHANES were used to estimate population-level caffeine intakes, using data from 24-h dietary recall. First, caffeine intakes by age-group and beverage type were estimated using the most recent 2011–2012 data (n = 7456. Second, fourteen years trends in caffeine consumption, overall and by beverage type, were evaluated for adults and children. Trend analyses were conducted by age groups. Last, trends in caffeine intakes by purchase location and beverage type were estimated. In 2011–2012, children aged four to eight years consumed the least caffeine (15 mg/day, and adults aged 51–70 years consumed the most (213 mg/day. The population mean (age ≥ four years was 135 mg/day, driven largely by coffee (90 mg/day, tea (25 mg/day, and soda (21 mg/day. For the 14–19 years and 20–34 years age-groups, energy drinks contributed 6 mg/day (9.9% and 5 mg/day (4.5%, respectively. The bulk of caffeine came from store-bought coffee and tea. Among both children and adults combined, caffeine intakes declined from 175 mg/day (1999–2000 to 142 mg/day (2011–2012, largely driven by a drop in caffeine from soda (41 mg/day to 21 mg/day. Store-bought coffee and tea remain principal drivers of caffeine intake in the US. Sodas and energy drinks make minor contributions to overall caffeine intakes.

  19. Anonymity Preserving Routing In Location Privacy Schemes In Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    R Regin

    2015-12-01

    Full Text Available Location privacy measures need to be developed to prevent the opponent from determining the physical locations of source sensors and sinks. An opponent can easily intercept network traffic due to the use of a broadcast medium for routing packets and get detailed information such as packet transmission time and frequency to perform traffic analysis and infer the locations of monitored objects and data sinks. On the other hand, sensors usually have limited processing speed and energy supplies. It is very expensive to apply traditional anonymous communication techniques for hiding the communication between sensor nodes and sinks. The existing source-location privacy protects the location of monitored objects to increase the number of messages sent by the source before the object is located by the attacker. The flooding technique has the source node send each packet through numerous paths to a sink making it difficult for an opponent to trace the source. The locations of sinks can be protected from a local eavesdropper by hashing the ID field in the packet header. But opponent can track sinks by carrying out time correlation and rate monitoring attacks. Besides protection some source nodes are transferring relatively large amounts of data in existing system. As a result, these nodes run out of battery faster due to improper position of nodes and sinks. Thus in the proposed system the sinks should be located as optimally as possible to reduce traffic flow and energy consumption for sensor nodes. Hence Sink placement problem is resolved for minimizing the delay as well as maximizing the lifetime of a WSN. Thus proposed system is efficient in terms of overhead and functionality when compared to existing system.

  20. Analysis of Energy Efficiency in Dynamic Optical Networks Employing Solar Energy Sources

    DEFF Research Database (Denmark)

    Wang, Jiayuan; Fagertun, Anna Manolova; Ruepp, Sarah Renée

    2013-01-01

    The paper presents energy efficient routing in dynamic optical networks, where solar energy sources are employed for the network nodes. Different parameters are evaluated, including the number of nodes that have access to solar energy sources, the different maximum solar output power, traffic type...... and the locations of solar powered nodes. Results show a maximum 39% savings in energy consumption with different increases in connection blocking probability....

  1. Modular sensor network node

    Science.gov (United States)

    Davis, Jesse Harper Zehring [Berkeley, CA; Stark, Jr., Douglas Paul; Kershaw, Christopher Patrick [Hayward, CA; Kyker, Ronald Dean [Livermore, CA

    2008-06-10

    A distributed wireless sensor network node is disclosed. The wireless sensor network node includes a plurality of sensor modules coupled to a system bus and configured to sense a parameter. The parameter may be an object, an event or any other parameter. The node collects data representative of the parameter. The node also includes a communication module coupled to the system bus and configured to allow the node to communicate with other nodes. The node also includes a processing module coupled to the system bus and adapted to receive the data from the sensor module and operable to analyze the data. The node also includes a power module connected to the system bus and operable to generate a regulated voltage.

  2. Related Drupal Nodes Block

    NARCIS (Netherlands)

    Van der Vegt, Wim

    2010-01-01

    Related Drupal Nodes Block This module exposes a block that uses Latent Semantic Analysis (Lsa) internally to suggest three nodes that are relevant to the node a user is viewing. This module performs three tasks. 1) It periodically indexes a Drupal site and generates a Lsa Term Document Matrix.

  3. Live and Dead Nodes

    DEFF Research Database (Denmark)

    Jørgensen, Sune Lehman; Jackson, A. D.

    2005-01-01

    In this paper, we explore the consequences of a distinction between `live' and `dead' network nodes; `live' nodes are able to acquire new links whereas `dead' nodes are static. We develop an analytically soluble growing network model incorporating this distinction and show that it can provide...

  4. phylo-node: A molecular phylogenetic toolkit using Node.js.

    Science.gov (United States)

    O'Halloran, Damien M

    2017-01-01

    Node.js is an open-source and cross-platform environment that provides a JavaScript codebase for back-end server-side applications. JavaScript has been used to develop very fast and user-friendly front-end tools for bioinformatic and phylogenetic analyses. However, no such toolkits are available using Node.js to conduct comprehensive molecular phylogenetic analysis. To address this problem, I have developed, phylo-node, which was developed using Node.js and provides a stable and scalable toolkit that allows the user to perform diverse molecular and phylogenetic tasks. phylo-node can execute the analysis and process the resulting outputs from a suite of software options that provides tools for read processing and genome alignment, sequence retrieval, multiple sequence alignment, primer design, evolutionary modeling, and phylogeny reconstruction. Furthermore, phylo-node enables the user to deploy server dependent applications, and also provides simple integration and interoperation with other Node modules and languages using Node inheritance patterns, and a customized piping module to support the production of diverse pipelines. phylo-node is open-source and freely available to all users without sign-up or login requirements. All source code and user guidelines are openly available at the GitHub repository: https://github.com/dohalloran/phylo-node.

  5. Effects of source and receiver locations in predicting room transfer functions by a phased beam tracing method

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho; Ih, Jeong-Guon

    2012-01-01

    The accuracy of a phased beam tracing method in predicting transfer functions is investigated with a special focus on the positions of the source and receiver. Simulated transfer functions for various source-receiver pairs using the phased beam tracing method were compared with analytical Green’s...

  6. Influence of the vibration source location on the modes of jet disintegration in the priller and on monodispersity of the finished product

    OpenAIRE

    Skydanenko, Maksym; Kononenko, Mykola; Kurdes, Yuliia

    2017-01-01

    Influence of the vibration source location on the modes of liquid jets disintegration and obtaining monodisperse droplets and granules of the finished product is theoretically grounded and experimentally confirmed. The experiment was conducted on an experimental stand of industrial granulation equipment.

  7. Protocol for multiple node network

    Science.gov (United States)

    Kirkham, Harold (Inventor)

    1995-01-01

    The invention is a multiple interconnected network of intelligent message-repeating remote nodes which employs an antibody recognition message termination process performed by all remote nodes and a remote node polling process performed by other nodes which are master units controlling remote nodes in respective zones of the network assigned to respective master nodes. Each remote node repeats only those messages originated in the local zone, to provide isolation among the master nodes.

  8. Implementation of Multiple Host Nodes in Wireless Sensing Node Network System for Landslide Monitoring

    International Nuclear Information System (INIS)

    Bin Abas, Faizulsalihin; Takayama, Shigeru

    2015-01-01

    This paper proposes multiple host nodes in Wireless Sensing Node Network System (WSNNS) for landslide monitoring. As landslide disasters damage monitoring system easily, one major demand in landslide monitoring is the flexibility and robustness of the system to evaluate the current situation in the monitored area. For various reasons WSNNS can provide an important contribution to reach that aim. In this system, acceleration sensors and GPS are deployed in sensing nodes. Location information by GPS, enable the system to estimate network topology and enable the system to perceive the location in emergency by monitoring the node mode. Acceleration sensors deployment, capacitate this system to detect slow mass movement that can lead to landslide occurrence. Once deployed, sensing nodes self-organize into an autonomous wireless ad hoc network. The measurement parameter data from sensing nodes is transmitted to Host System via host node and ''Cloud'' System. The implementation of multiple host nodes in Local Sensing Node Network System (LSNNS), improve risk- management of the WSNNS for real-time monitoring of landslide disaster

  9. Implementation of Multiple Host Nodes in Wireless Sensing Node Network System for Landslide Monitoring

    Science.gov (United States)

    Abas, Faizulsalihin bin; Takayama, Shigeru

    2015-02-01

    This paper proposes multiple host nodes in Wireless Sensing Node Network System (WSNNS) for landslide monitoring. As landslide disasters damage monitoring system easily, one major demand in landslide monitoring is the flexibility and robustness of the system to evaluate the current situation in the monitored area. For various reasons WSNNS can provide an important contribution to reach that aim. In this system, acceleration sensors and GPS are deployed in sensing nodes. Location information by GPS, enable the system to estimate network topology and enable the system to perceive the location in emergency by monitoring the node mode. Acceleration sensors deployment, capacitate this system to detect slow mass movement that can lead to landslide occurrence. Once deployed, sensing nodes self-organize into an autonomous wireless ad hoc network. The measurement parameter data from sensing nodes is transmitted to Host System via host node and "Cloud" System. The implementation of multiple host nodes in Local Sensing Node Network System (LSNNS), improve risk- management of the WSNNS for real-time monitoring of landslide disaster.

  10. New sites of Australasian microtektites in the central Indian Ocean: Implications for the location and size of source crater

    Digital Repository Service at National Institute of Oceanography (India)

    ShyamPrasad, M.; Mahale, V.P.; Kodagali, V.N.

    Fifteen new Australasian microtektite sites have been identified along a transect roughly N-S in the central Indian Ocean. These locations, in addition to the existing 46 sites, total to 61 microtektite sites in the oceans. We carried out regression...

  11. Mining Important Nodes in Directed Weighted Complex Networks

    Directory of Open Access Journals (Sweden)

    Yunyun Yang

    2017-01-01

    Full Text Available In complex networks, mining important nodes has been a matter of concern by scholars. In recent years, scholars have focused on mining important nodes in undirected unweighted complex networks. But most of the methods are not applicable to directed weighted complex networks. Therefore, this paper proposes a Two-Way-PageRank method based on PageRank for further discussion of mining important nodes in directed weighted complex networks. We have mainly considered the frequency of contact between nodes and the length of time of contact between nodes. We have considered the source of the nodes (in-degree and the whereabouts of the nodes (out-degree simultaneously. We have given node important performance indicators. Through numerical examples, we analyze the impact of variation of some parameters on node important performance indicators. Finally, the paper has verified the accuracy and validity of the method through empirical network data.

  12. Contrast enhanced ultrasound of sentinel lymph nodes

    Directory of Open Access Journals (Sweden)

    XinWu Cui

    2013-03-01

    Full Text Available Sentinel lymph nodes are the first lymph nodes in the region that receive lymphatic drainage from a primary tumor. The detection or exclusion of sentinel lymph node micrometastases is critical in the staging of cancer, especially breast cancer and melanoma because it directly affects patient’s prognosis and surgical management. Currently, intraoperative sentinel lymph node biopsies using blue dye and radioisotopes are the method of choice for the detection of sentinel lymph node with high identification rate. In contrast, conventional ultrasound is not capable of detecting sentinel lymph nodes in most cases. Contrast enhanced ultrasound with contrast specific imaging modes has been used for the evaluation and diagnostic work-up of peripherally located suspected lymphadenopathy. The method allows for real-time analysis of all vascular phases and the visualization of intranodal focal “avascular” areas that represent necrosis or deposits of neoplastic cells. In recent years, a number of animal and human studies showed that contrast enhanced ultrasound can be also used for the detection of sentinel lymph node, and may become a potential application in clinical routine. Several contrast agents have been used in those studies, including albumin solution, hydroxyethylated starch, SonoVue®, Sonazoid® and Definity®. This review summarizes the current knowledge about the use of ultrasound techniques in detection and evaluation of sentinel lymph node.

  13. Study of the precision of the gamma-ray burst source locations obtained with the Ulysses/PVO/CGRO network

    International Nuclear Information System (INIS)

    Cline, T.L.; Hurley, K.C.; Sommer, M.; Boer, M.; Niel, M.; Fishman, G.; Kouveliotou, C.; Meegan, C.; Paciesas, W.S.; Wilson, R.B.; Laros, J.G.; Klebesadel, R.W.

    1994-01-01

    The interplanetary gamma-ray burst network of the Ulysses, Compton-GRO, and Pioneer-Venus Orbiter missions has made source localizations with fractional-arc-minute precision for a number of events, and with auxiliary data, will provide useful annular-segment loci for many more. These studies have, thus far, yielded one possible counterpart, a Rosat x-ray association with the 92 May 1 burst. Similar to the historic 1978 November 19 burst/Einstein association, this possibility gives hope that network studies will provide a fundamental source clue for 'classical' bursts, just as a second supernova remnant in a network-defined source field has done for sgr events

  14. Lippmann-Schwinger integral equation approach to the emission of radiation by sources located inside finite-sized dielectric structures

    DEFF Research Database (Denmark)

    Søndergaard, T.; Tromborg, Bjarne

    2002-01-01

    uses for analyzing the emission of light by sources in some antennas and optical components such as vertical cavity surface emitting lasers, microdisk lasers, and light emitting diodes. The methods also have prospective uses in quantum electrodynamics for studies of spontaneous emission from, e...

  15. The deposition of anal excretions by Melipona favosa foragers (Apidae: Meliponinae): behavioural observations concerning the location of food sources

    NARCIS (Netherlands)

    Aguilar, I. (Ingrid); Sommeijer, M.J.

    2000-01-01

    Melipona favosa consistently deposited anal excretions while foraging. Anal depositions were released more frequently and by more bees on artificial food sources at a greater distance from the nest. Our hypothesis that these deposits serve as scent marks is supported by experimental evidence

  16. A New Approach to Design Autonomous Wireless Sensor Node Based on RF Energy Harvesting System.

    Science.gov (United States)

    Mouapi, Alex; Hakem, Nadir

    2018-01-05

    Energy Harvesting techniques are increasingly seen as the solution for freeing the wireless sensor nodes from their battery dependency. However, it remains evident that network performance features, such as network size, packet length, and duty cycle, are influenced by the sum of recovered energy. This paper proposes a new approach to defining the specifications of a stand-alone wireless node based on a Radio-frequency Energy Harvesting System (REHS). To achieve adequate performance regarding the range of the Wireless Sensor Network (WSN), techniques for minimizing the energy consumed by the sensor node are combined with methods for optimizing the performance of the REHS. For more rigor in the design of the autonomous node, a comprehensive energy model of the node in a wireless network is established. For an equitable distribution of network charges between the different nodes that compose it, the Low-Energy Adaptive Clustering Hierarchy (LEACH) protocol is used for this purpose. The model considers five energy-consumption sources, most of which are ignored in recently used models. By using the hardware parameters of commercial off-the-shelf components (Mica2 Motes and CC2520 of Texas Instruments), the energy requirement of a sensor node is quantified. A miniature REHS based on a judicious choice of rectifying diodes is then designed and developed to achieve optimal performance in the Industrial Scientific and Medical (ISM) band centralized at 2.45 GHz . Due to the mismatch between the REHS and the antenna, a band pass filter is designed to reduce reflection losses. A gradient method search is used to optimize the output characteristics of the adapted REHS. At 1 mW of input RF power, the REHS provides an output DC power of 0.57 mW and a comparison with the energy requirement of the node allows the Base Station (BS) to be located at 310 m from the wireless nodes when the Wireless Sensor Network (WSN) has 100 nodes evenly spread over an area of 300 × 300 m 2 and

  17. A New Approach to Design Autonomous Wireless Sensor Node Based on RF Energy Harvesting System

    Directory of Open Access Journals (Sweden)

    Alex Mouapi

    2018-01-01

    Full Text Available Energy Harvesting techniques are increasingly seen as the solution for freeing the wireless sensor nodes from their battery dependency. However, it remains evident that network performance features, such as network size, packet length, and duty cycle, are influenced by the sum of recovered energy. This paper proposes a new approach to defining the specifications of a stand-alone wireless node based on a Radio-frequency Energy Harvesting System (REHS. To achieve adequate performance regarding the range of the Wireless Sensor Network (WSN, techniques for minimizing the energy consumed by the sensor node are combined with methods for optimizing the performance of the REHS. For more rigor in the design of the autonomous node, a comprehensive energy model of the node in a wireless network is established. For an equitable distribution of network charges between the different nodes that compose it, the Low-Energy Adaptive Clustering Hierarchy (LEACH protocol is used for this purpose. The model considers five energy-consumption sources, most of which are ignored in recently used models. By using the hardware parameters of commercial off-the-shelf components (Mica2 Motes and CC2520 of Texas Instruments, the energy requirement of a sensor node is quantified. A miniature REHS based on a judicious choice of rectifying diodes is then designed and developed to achieve optimal performance in the Industrial Scientific and Medical (ISM band centralized at 2.45 GHz . Due to the mismatch between the REHS and the antenna, a band pass filter is designed to reduce reflection losses. A gradient method search is used to optimize the output characteristics of the adapted REHS. At 1 mW of input RF power, the REHS provides an output DC power of 0.57 mW and a comparison with the energy requirement of the node allows the Base Station (BS to be located at 310 m from the wireless nodes when the Wireless Sensor Network (WSN has 100 nodes evenly spread over an area of 300

  18. Comparison of imaging modalities and source-localization algorithms in locating the induced activity during deep brain stimulation of the STN.

    Science.gov (United States)

    Mideksa, K G; Singh, A; Hoogenboom, N; Hellriegel, H; Krause, H; Schnitzler, A; Deuschl, G; Raethjen, J; Schmidt, G; Muthuraman, M

    2016-08-01

    One of the most commonly used therapy to treat patients with Parkinson's disease (PD) is deep brain stimulation (DBS) of the subthalamic nucleus (STN). Identifying the most optimal target area for the placement of the DBS electrodes have become one of the intensive research area. In this study, the first aim is to investigate the capabilities of different source-analysis techniques in detecting deep sources located at the sub-cortical level and validating it using the a-priori information about the location of the source, that is, the STN. Secondly, we aim at an investigation of whether EEG or MEG is best suited in mapping the DBS-induced brain activity. To do this, simultaneous EEG and MEG measurement were used to record the DBS-induced electromagnetic potentials and fields. The boundary-element method (BEM) have been used to solve the forward problem. The position of the DBS electrodes was then estimated using the dipole (moving, rotating, and fixed MUSIC), and current-density-reconstruction (CDR) (minimum-norm and sLORETA) approaches. The source-localization results from the dipole approaches demonstrated that the fixed MUSIC algorithm best localizes deep focal sources, whereas the moving dipole detects not only the region of interest but also neighboring regions that are affected by stimulating the STN. The results from the CDR approaches validated the capability of sLORETA in detecting the STN compared to minimum-norm. Moreover, the source-localization results using the EEG modality outperformed that of the MEG by locating the DBS-induced activity in the STN.

  19. Deploying Node.js

    CERN Document Server

    Pasquali, Sandro

    2015-01-01

    If you are an intermediate or advanced developer deploying your Node.js applications, then this book is for you. If you have already built a Node application or module and want to take your knowledge to the next level, this book will help you find your way.

  20. Defining nodes in complex brain networks

    Directory of Open Access Journals (Sweden)

    Matthew Lawrence Stanley

    2013-11-01

    Full Text Available Network science holds great promise for expanding our understanding of the human brain in health, disease, development, and aging. Network analyses are quickly becoming the method of choice for analyzing functional MRI data. However, many technical issues have yet to be confronted in order to optimize results. One particular issue that remains controversial in functional brain network analyses is the definition of a network node. In functional brain networks a node represents some predefined collection of brain tissue, and an edge measures the functional connectivity between pairs of nodes. The characteristics of a node, chosen by the researcher, vary considerably in the literature. This manuscript reviews the current state of the art based on published manuscripts and highlights the strengths and weaknesses of three main methods for defining nodes. Voxel-wise networks are constructed by assigning a node to each, equally sized brain area (voxel. The fMRI time-series recorded from each voxel is then used to create the functional network. Anatomical methods utilize atlases to define the nodes based on brain structure. The fMRI time-series from all voxels within the anatomical area are averaged and subsequently used to generate the network. Functional activation methods rely on data from traditional fMRI activation studies, often from databases, to identify network nodes. Such methods identify the peaks or centers of mass from activation maps to determine the location of the nodes. Small (~10-20 millimeter diameter spheres located at the coordinates of the activation foci are then applied to the data being used in the network analysis. The fMRI time-series from all voxels in the sphere are then averaged, and the resultant time series is used to generate the network. We attempt to clarify the discussion and move the study of complex brain networks forward. While the correct method to be used remains an open, possibly unsolvable question that

  1. Rate Proposal for Remuneration of Air Pollutants Emissions From Stationary Sources Located in Bogota D.C.

    Directory of Open Access Journals (Sweden)

    Gabriel Herrera Torres

    2011-04-01

    Full Text Available The objective of this project is to develop a methodological proposal for the establishment of the retributive rate for the direct use of the atmosphere as the receptor of pollutant emissions that come from stationary resources on Bogotá D.C. By means of the emissions from stationary sources inventory and the air quality analysis, the pollutant that are emitted by the industries and the ones that are regulated by the network observations of the were identified selecting the particulated matter (PM10, sulfur oxides (SOx, and nitrogen oxides (NOx as the atmospheric pollutants that should be the object of payment in the retributive rate. Besides the selection of the pollutants that should be in the payment, the analysis of the retributive rate structure was made witch was based on the description or four key elements the generated fact, the tax base, the passive subject, and the fee of the rate. taking into account the social costs which are related to the investment being made by the district for the treatment of patients that present acute respiratory diseases ERA´s, associated and the costs of program control and monitoring of the air quality in Bogotá, the tariffs of the payment of the retributive rate were redefined in 281 $/Kg for the PM10, 2816 $/kg for the SOX and 2866 $/kg for NOX. Finally a new model of the payment was established, which is the result of the multiplication of the respective tariff for each of the pollutants that were selected as object of payment, expressed in ($/kg times, the charge of the pollutants emitted by the source expressed in (kg/ day.times the total number of days of the operation of the source emissions in a year.

  2. Automated phase picker and source location algorithm for local distances using a single three component seismic station

    International Nuclear Information System (INIS)

    Saari, J.

    1989-12-01

    The paper describes procedures for automatic location of local events by using single-site, three-component (3c) seismogram records. Epicentral distance is determined from the time difference between P- and S-onsets. For onset time estimates a special phase picker algorithm is introduced. Onset detection is accomplished by comparing short-term average with long-term average after multiplication of north, east and vertical components of recording. For epicentral distances up to 100 km, errors seldom exceed 5 km. The slowness vector, essentially the azimuth, is estimated independently by using the Christoffersson et al. (1988) 'polarization' technique, although a priori knowledge of the P-onset time gives the best results. Differences between 'true' and observed azimuths are generally less than 12 deg C. Practical examples are given by demonstrating the viability of the procedures for automated 3c seismogram analysis. The results obtained compare favourably with those achieved by a miniarray of three stations. (orig.)

  3. Degrees of sustainable location of railway stations : Integrating space syntax and node place value model on railway sations in the province of North Holland's strategic plan for 2010-2040

    NARCIS (Netherlands)

    Van Nes, A.; Stolk, E.

    2012-01-01

    Mobility on rails is acknowledged to be one of the most sustainable means of transportation between cities and towns. Therefore, a railway station’s location in a built environment and its degree of accessibility is essential to reach as many travellers as possible. Even though there exist several

  4. Controls of tectonics and sediment source locations on along-strike variations in transgressive deposits on the northern California margin

    Science.gov (United States)

    Spinelli, G.A.; Field, M.E.

    2003-01-01

    We identify two surfaces in the shallow subsurface on the Eel River margin offshore northern California, a lowstand erosion surface, likely formed during the last glacial maximum, and an overlying surface likely formed during the most recent transgression of the shoreline. The lowstand erosion surface, which extends from the inner shelf to near the shelfbreak and from the Eel River to Trinidad Head (???80 km), truncates underlying strata on the shelf. Above the surface, inferred transgressive coastal and estuarine sedimentary units separate it from the transgressive surface on the shelf. Early in the transgression, Eel River sediment was likely both transported down the Eel Canyon and dispersed on the slope, allowing transgressive coastal sediment from the smaller Mad River to accumulate in a recognizable deposit on the shelf. The location of coastal Mad River sediment accumulation was controlled by the location of the paleo-Mad River. Throughout the remainder of the transgression, dispersed sediment from the Eel River accumulated an average of 20 m of onlapping shelf deposits. The distribution and thickness of these transgressive marine units was strongly modified by northwest-southeast trending folds. Thick sediment packages accumulated over structural lows in the lowstand surface. The thinnest sediment accumulations (0-10 m) were deposited over structural highs along faults and uplifting anticlines. The Eel margin, an active margin with steep, high sediment-load streams, has developed a thick transgressive systems tract. On this margin sediment accumulates as rapidly as the processes of uplift and downwarp locally create and destroy accommodation space. Sequence stratigraphic models of tectonically active margins should account for variations in accommodation space along margins as well as across them. ?? 2003 Elsevier Science B.V. All rights reserved.

  5. Node-Dependence-Based Dynamic Incentive Algorithm in Opportunistic Networks

    Directory of Open Access Journals (Sweden)

    Ruiyun Yu

    2014-01-01

    Full Text Available Opportunistic networks lack end-to-end paths between source nodes and destination nodes, so the communications are mainly carried out by the “store-carry-forward” strategy. Selfish behaviors of rejecting packet relay requests will severely worsen the network performance. Incentive is an efficient way to reduce selfish behaviors and hence improves the reliability and robustness of the networks. In this paper, we propose the node-dependence-based dynamic gaming incentive (NDI algorithm, which exploits the dynamic repeated gaming to motivate nodes relaying packets for other nodes. The NDI algorithm presents a mechanism of tolerating selfish behaviors of nodes. Reward and punishment methods are also designed based on the node dependence degree. Simulation results show that the NDI algorithm is effective in increasing the delivery ratio and decreasing average latency when there are a lot of selfish nodes in the opportunistic networks.

  6. Magnetic Data Interpretation for the Source-Edge Locations in Parts of the Tectonically Active Transition Zone of the Narmada-Son Lineament in Central India

    Science.gov (United States)

    Ghosh, G. K.

    2016-02-01

    The study has been carried out in the transition zone of the Narmada-Son lineament (NSL) which is seismically active with various geological complexities, upwarp movement of the mantle material into the crust through fault, fractures lamination and upwelling. NSL is one of the most prominent lineaments in central India after the Himalaya in the Indian geology. The area of investigation extends from longitude 80.25°E to 81.50°E and latitude 23.50°N to 24.37°N in the central part of the Indian continent. Different types of subsurface geological formations viz. alluvial, Gondwana, Deccan traps, Vindhyan, Mahakoshal, Granite and Gneisses groups exist in this area with varying geological ages. In this study area tectonic movement and crustal variation have been taken place during the past time and which might be reason for the variation of magnetic field. Magnetic anomaly suggests that the area has been highly disturbed which causes the Narmada-Son lineament trending in the ENE-WSW direction. Magnetic anomaly variation has been taken place due to the lithological variations subject to the changes in the geological contacts like thrusts and faults in this area. Shallow and deeper sources have been distinguished using frequency domain analysis by applying different filters. To enhance the magnetic data, various types of derivatives to identify the source-edge locations of the causative source bodies. The present study carried out the interpretation using total horizontal derivative, tilt angle derivative, horizontal tilt angle derivative and Cos (θ) derivative map to get source-edge locations. The results derived from various derivatives of magnetic data have been compared with the basement depth solutions calculated from 3D Euler deconvolution. It is suggested that total horizontal derivative, tilt angle derivative and Cos (θ) derivative are the most useful tools for identifying the multiple source edge locations of the causative bodies in this tectonically active

  7. Gravitational wave sources from Pop III stars are preferentially located within the cores of their host Galaxies

    Science.gov (United States)

    Pacucci, Fabio; Loeb, Abraham; Salvadori, Stefania

    2017-10-01

    The detection of gravitational waves (GWs) generated by merging black holes has recently opened up a new observational window into the Universe. The mass of the black holes in the first and third Laser Interferometer Gravitational Wave Observatory (LIGO) detections (36-29 M⊙ and 32-19 M⊙) suggests low-metallicity stars as their most likely progenitors. Based on high-resolution N-body simulations, coupled with state-of-the-art metal enrichment models, we find that the remnants of Pop III stars are preferentially located within the cores of galaxies. The probability of a GW signal to be generated by Pop III stars reaches ∼90 per cent at ∼0.5 kpc from the galaxy centre, compared to a benchmark value of ∼5 per cent outside the core. The predicted merger rates inside bulges is ∼60 × βIII Gpc-3 yr-1 (βIII is the Pop III binarity fraction). To match the 90 per cent credible range of LIGO merger rates, we obtain: 0.03 proof for the existence of Pop III stars.

  8. Sentinel lymph node biopsy: clinical relevance

    International Nuclear Information System (INIS)

    Howman-Giles, R.

    2002-01-01

    Sentinel lymph node biopsy (SLNB) has become an important technique in the management of patients with intermediate level melanoma, clinical operable breast cancer and some other cancers. The technique relies on lymphatic mapping to define the lymph drainage from a primary tumour with the premise that the lymph nodes, which directly drain from that area, will reflect the tumour status of the remainder of the node field. Current techniques use lymphoscintigraphy where a radioactive labelled particle and / or blue dye are injected intradermally or intraparenchymally to map the lymph drainage, often in conjunction with a radioactive gamma probe at surgery. In patients with melanoma the SLNB has improved the staging and prognostic information by more accurate determination of whether regional lymph nodes have metastatic spread. This has a major impact on patient management as those patients with negative nodes do not require regional lymph node dissection and have a significantly better prognosis. In our experience of over 3000 patients the combined sentinel node biopsy technique localised accurately 98% of sentinel lymph nodes. Lymphoscintigraphy in patients with melanoma to locate the sentinel lymph nodes involves the intradermal injection of a radiocolloid around the melanoma site or the excision biopsy site. Injections of 5 -10 MBq in 0.05-0.1ml/inj are used and typically 4 injections are usually required. Following tracer injection dynamic imaging is performed to follow the lymphatic collecting vessels until they reach the draining sentinel nodes. An image should be acquired as the vessels reach the node field so that the sentinel nodes directly receiving the channels can be identified and distinguished from any second tier nodes which may sometimes be seen. Delayed scans are performed 2 hours later at which time all regions which can possible drain the primary melanoma site are examined with 5-10 minute static images. The surface location of all sentinel nodes is

  9. Implications of wall recycling and carbon source locations on core plasma fueling and impurity content in DIII-D

    International Nuclear Information System (INIS)

    Groth, M.; Porter, G.D.; Fenstermacher, M.E.; Lasnier, C.J.; Meyer, W.M.; Rensink, M.E.; Wolf, N.S.; Boedo, J.A.; Moyer, R.A.; Rudakov, D.L.; Brooks, N.H.; Groebner, R.J.; Petrie, T.W.; Owen, L.W.; Wang, G.; Zeng, L.; Watkins, J.G.

    2005-01-01

    Measurement and modeling of the 2-D poloidal D α intensity distribution in DIII-D low and medium density L-mode and ELMy H-mode plasmas indicate that hydrogen neutrals predominantly fuel the core from the divertor X-point region. The 2-D distribution of neutral deuterium and low-charge-state carbon were measured in the divertor and the high-field side midplane scrape-off layer (SOL) using tangentially viewing cameras. The emission in the high-field SOL at the equatorial plane was found to be three to four orders of magnitude lower than at the strike points in the divertor, suggesting a strong divertor particle source. Modeling using the UEDGE/DEGAS codes predicted the poloidal fueling distribution to be dependent on the direction of the ion Bx∇B drift. In plasmas with the Bx∇B drift into the divertor stronger fueling from the inner divertor than from the outer is predicted, due to a lower-temperature and higher-density plasma in the inner leg. UEDGE simulations with carbon produced by both physical and chemical sputtering at the divertor plates and walls only are in agreement with a large set of diagnostic data. The simulations indicate flow reversal in the inner divertor that augments the leakage of carbon ions from the divertor into the core. (author)

  10. An open data repository for steady state analysis of a 100-node electricity distribution network with moderate connection of renewable energy sources.

    Science.gov (United States)

    Lazarou, Stavros; Vita, Vasiliki; Ekonomou, Lambros

    2018-02-01

    The data of this article represent a real electricity distribution network on twenty kilovolts (20 kV) at medium voltage level of the Hellenic electricity distribution system [1]. This network has been chosen as suitable for smart grid analysis. It demonstrates moderate penetration of renewable sources and it has capability in part of time for reverse power flows. It is suitable for studies of load aggregation, storage, demand response. It represents a rural line of fifty-five kilometres (55 km) total length, a typical length for this type. It serves forty-five (45) medium to low voltage transformers and twenty-four (24) connections to photovoltaic plants. The total installed load capacity is twelve mega-volt-ampere (12 MVA), however the maximum observed load is lower. The data are ready to perform load flow simulation on Matpower [2] for the maximum observed load power on the half production for renewables. The simulation results and processed data for creating the source code are also provided on the database available at http://dx.doi.org/10.7910/DVN/1I6MKU.

  11. Intelligent Mission Controller Node

    National Research Council Canada - National Science Library

    Perme, David

    2002-01-01

    The goal of the Intelligent Mission Controller Node (IMCN) project was to improve the process of translating mission taskings between real-world Command, Control, Communications, Computers, and Intelligence (C41...

  12. Lymph node culture

    Science.gov (United States)

    Culture - lymph node ... or viruses grow. This process is called a culture. Sometimes, special stains are also used to identify specific cells or microorganisms before culture results are available. If needle aspiration does not ...

  13. Mental Health and Drivers of Need in Emergent and Non-Emergent Emergency Department (ED) Use: Do Living Location and Non-Emergent Care Sources Matter?

    Science.gov (United States)

    McManus, Moira C; Cramer, Robert J; Boshier, Maureen; Akpinar-Elci, Muge; Van Lunen, Bonnie

    2018-01-13

    Emergency department (ED) utilization has increased due to factors such as admissions for mental health conditions, including suicide and self-harm. We investigate direct and moderating influences on non-emergent ED utilization through the Behavioral Model of Health Services Use. Through logistic regression, we examined correlates of ED use via 2014 New York State Department of Health Statewide Planning and Research Cooperative System outpatient data. Consistent with the primary hypothesis, mental health admissions were associated with emergent use across models, with only a slight decrease in effect size in rural living locations. Concerning moderating effects, Spanish/Hispanic origin was associated with increased likelihood for emergent ED use in the rural living location model, and non-emergent ED use for the no non-emergent source model. 'Other' ethnic origin increased the likelihood of emergent ED use for rural living location and no non-emergent source models. The findings reveal 'need', including mental health admissions, as the largest driver for ED use. This may be due to mental healthcare access, or patients with mental health emergencies being transported via first responders to the ED, as in the case of suicide, self-harm, manic episodes or psychotic episodes. Further educating ED staff on this patient population through gatekeeper training may ensure patients receive the best treatment and aid in driving access to mental healthcare delivery changes.

  14. Sink-oriented Dynamic Location Service Protocol for Mobile Sinks with an Energy Efficient Grid-Based Approach

    Directory of Open Access Journals (Sweden)

    Hyunseung Choo

    2009-03-01

    Full Text Available Sensor nodes transmit the sensed information to the sink through wireless sensor networks (WSNs. They have limited power, computational capacities and memory. Portable wireless devices are increasing in popularity. Mechanisms that allow information to be efficiently obtained through mobile WSNs are of significant interest. However, a mobile sink introduces many challenges to data dissemination in large WSNs. For example, it is important to efficiently identify the locations of mobile sinks and disseminate information from multi-source nodes to the multi-mobile sinks. In particular, a stationary dissemination path may no longer be effective in mobile sink applications, due to sink mobility. In this paper, we propose a Sink-oriented Dynamic Location Service (SDLS approach to handle sink mobility. In SDLS, we propose an Eight-Direction Anchor (EDA system that acts as a location service server. EDA prevents intensive energy consumption at the border sensor nodes and thus provides energy balancing to all the sensor nodes. Then we propose a Location-based Shortest Relay (LSR that efficiently forwards (or relays data from a source node to a sink with minimal delay path. Our results demonstrate that SDLS not only provides an efficient and scalable location service, but also reduces the average data communication overhead in scenarios with multiple and moving sinks and sources.

  15. Sink-oriented Dynamic Location Service Protocol for Mobile Sinks with an Energy Efficient Grid-Based Approach.

    Science.gov (United States)

    Jeon, Hyeonjae; Park, Kwangjin; Hwang, Dae-Joon; Choo, Hyunseung

    2009-01-01

    Sensor nodes transmit the sensed information to the sink through wireless sensor networks (WSNs). They have limited power, computational capacities and memory. Portable wireless devices are increasing in popularity. Mechanisms that allow information to be efficiently obtained through mobile WSNs are of significant interest. However, a mobile sink introduces many challenges to data dissemination in large WSNs. For example, it is important to efficiently identify the locations of mobile sinks and disseminate information from multi-source nodes to the multi-mobile sinks. In particular, a stationary dissemination path may no longer be effective in mobile sink applications, due to sink mobility. In this paper, we propose a Sink-oriented Dynamic Location Service (SDLS) approach to handle sink mobility. In SDLS, we propose an Eight-Direction Anchor (EDA) system that acts as a location service server. EDA prevents intensive energy consumption at the border sensor nodes and thus provides energy balancing to all the sensor nodes. Then we propose a Location-based Shortest Relay (LSR) that efficiently forwards (or relays) data from a source node to a sink with minimal delay path. Our results demonstrate that SDLS not only provides an efficient and scalable location service, but also reduces the average data communication overhead in scenarios with multiple and moving sinks and sources.

  16. Connecting smoke plumes to sources using Hazard Mapping System (HMS) smoke and fire location data over North America

    Science.gov (United States)

    Brey, Steven J.; Ruminski, Mark; Atwood, Samuel A.; Fischer, Emily V.

    2018-02-01

    Fires represent an air quality challenge because they are large, dynamic and transient sources of particulate matter and ozone precursors. Transported smoke can deteriorate air quality over large regions. Fire severity and frequency are likely to increase in the future, exacerbating an existing problem. Using the National Environmental Satellite, Data, and Information Service (NESDIS) Hazard Mapping System (HMS) smoke data for North America for the period 2007 to 2014, we examine a subset of fires that are confirmed to have produced sufficient smoke to warrant the initiation of a U.S. National Weather Service smoke forecast. We find that gridded HMS-analyzed fires are well correlated (r = 0.84) with emissions from the Global Fire Emissions Inventory Database 4s (GFED4s). We define a new metric, smoke hours, by linking observed smoke plumes to active fires using ensembles of forward trajectories. This work shows that the Southwest, Northwest, and Northwest Territories initiate the most air quality forecasts and produce more smoke than any other North American region by measure of the number of HYSPLIT points analyzed, the duration of those HYSPLIT points, and the total number of smoke hours produced. The average number of days with smoke plumes overhead is largest over the north-central United States. Only Alaska, the Northwest, the Southwest, and Southeast United States regions produce the majority of smoke plumes observed over their own borders. This work moves a new dataset from a daily operational setting to a research context, and it demonstrates how changes to the frequency or intensity of fires in the western United States could impact other regions.

  17. Experimental studies of metastases of esophageal carcinoma to lymph nodes

    International Nuclear Information System (INIS)

    Inoue, Kazumasa

    1977-01-01

    Marked progress has been made in surgery for esophageal carcinoma, however, when compared to results of surgery for other carcinomas of the digestive tract, much research remains to be done. The author transplanted VX2 carcinoma, a transplantable tumor of the rabbit, to the esophagus in attempt to determine the mode of metastases of esophageal carcinoma to lymph nodes and also to observe the effect of chemotherapy (Bleomycin) and radiotherapy (Betatron). Carcinoma of the cervical esophagus metastasized to the cervical lymph nodes and then to the paratracheal lymph nodes. Carcinoma of the upper thoracic esophagus metastasized to the paratracheal lymph nodes and then to the cervical lymph nodes. Carcinoma of the mid-thoracic esophagus metastasized to the intrathoracic lymph nodes and then to the intraperitoneal lymph nodes. Carcinoma of the abdominal esophagus metastasized to the intraperitoneal lymph nodes and then to the intrathoracic lymph nodes. Skipping metastasis was rarely observed. Carcinoma of the thoracic esophagus with metastases of lymph nodes in the cervical or abdominal portion was considerably advanced, therefore it is considered that cleaning of the intrathoracic lymph nodes and simultaneous chemotherapy are required when such cases are encountered clinically. Irradiation resulted in regression in the size of the tumor and metastases to lymph nodes and there was a decrease in metastases to the distant lymph nodes. Effects of irradiation were similar on tumors and lymph nodes with positive metastases located within the field of irradiation. Bleomycin medication resulted in regression in the size of tumor and metastases to lymph nodes. Effects of Bleomycin medication were similar on tumors and lymph nodes with positive metastases. (auth.)

  18. An application of time-frequency signal analysis technique to estimate the location of an impact source on a plate type structure

    International Nuclear Information System (INIS)

    Park, Jin Ho; Lee, Jeong Han; Choi, Young Chul; Kim, Chan Joong; Seong, Poong Hyun

    2005-01-01

    It has been reviewed whether it would be suitable that the application of the time-frequency signal analysis techniques to estimate the location of the impact source in plate structure. The STFT(Short Time Fourier Transform), WVD(Wigner-Ville distribution) and CWT(Continuous Wavelet Transform) methods are introduced and the advantages and disadvantages of those methods are described by using a simulated signal component. The essential of the above proposed techniques is to separate the traveling waves in both time and frequency domains using the dispersion characteristics of the structural waves. These time-frequency methods are expected to be more useful than the conventional time domain analyses for the impact localization problem on a plate type structure. Also it has been concluded that the smoothed WVD can give more reliable means than the other methodologies for the location estimation in a noisy environment

  19. Genetic variation in total number and locations of GnRH neurons identified using in situ hybridization in a wild-source population.

    Science.gov (United States)

    Kaugars, Katherine E; Rivers, Charlotte I; Saha, Margaret S; Heideman, Paul D

    2016-02-01

    The evolution of brain function in the regulation of physiology may depend in part upon the numbers and locations of neurons. Wild populations of rodents contain natural genetic variation in the inhibition of reproduction by winter-like short photoperiod, and it has been hypothesized that this functional variation might be due in part to heritable variation in the numbers or location of gonadotropin releasing hormone (GnRH) neurons. A naturally variable wild-source population of white-footed mice was used to develop lines artificially selected for or against mature gonads in short, winter-like photoperiods. We compared a selection line that is reproductively inhibited in short photoperiod (Responsive) to a line that is weakly inhibited by short photoperiod (Nonresponsive) for differences in counts of neurons identified using in situ hybridization for GnRH mRNA. There was no effect of photoperiod, but there were 60% more GnRH neurons in total in the Nonresponsive selection line than the Responsive selection line. The lines differed specifically in numbers of GnRH neurons in more anterior regions, whereas numbers of GnRH neurons in posterior areas were not statistically different between lines. We compare these results to those of an earlier study that used immunohistochemical labeling for GnRH neurons. The results are consistent with the hypothesis that the selection lines and natural source population contain significant genetic variation in the number and location of GnRH neurons. The variation in GnRH neurons may contribute to functional variation in fertility that occurs in short photoperiods in the laboratory and in the wild source population in winter. © 2015 Wiley Periodicals, Inc.

  20. Analytic model of the stress waves propagation in thin wall tubes, seeking the location of a harmonic point source in its surface

    International Nuclear Information System (INIS)

    Boaratti, Mario Francisco Guerra

    2006-01-01

    Leaks in pressurized tubes generate acoustic waves that propagate through the walls of these tubes, which can be captured by accelerometers or by acoustic emission sensors. The knowledge of how these walls can vibrate, or in another way, how these acoustic waves propagate in this material is fundamental in the detection and localization process of the leak source. In this work an analytic model was implemented, through the motion equations of a cylindrical shell, with the objective to understand the behavior of the tube surface excited by a point source. Since the cylindrical surface has a closed pattern in the circumferential direction, waves that are beginning their trajectory will meet with another that has already completed the turn over the cylindrical shell, in the clockwise direction as well as in the counter clockwise direction, generating constructive and destructive interferences. After enough time of propagation, peaks and valleys in the shell surface are formed, which can be visualized through a graphic representation of the analytic solution created. The theoretical results were proven through measures accomplished in an experimental setup composed of a steel tube finished in sand box, simulating the condition of infinite tube. To determine the location of the point source on the surface, the process of inverse solution was adopted, that is to say, known the signals of the sensor disposed in the tube surface , it is determined through the theoretical model where the source that generated these signals can be. (author)

  1. Three-dimensional conformal radiation may deliver considerable dose of incidental nodal irradiation in patients with early stage node-negative non-small cell lung cancer when the tumor is large and centrally located

    International Nuclear Information System (INIS)

    Zhao Lujun; Chen Ming; Haken, Randall ten; Chetty, Indrin; Chapet, Olivier; Hayman, James A.; Kong Fengming

    2007-01-01

    Background and purpose: To determine the dose to regional nodal stations in patients with T 1-3 N 0 M 0 non-small cell lung cancer (NSCLC) treated with three-dimensional conformal radiation therapy (3DCRT) without intentional elective nodal irradiation (ENI). Materials and methods: Twenty-three patients with medically inoperable T 1-3 N 0 M 0 NSCLC were treated with 3DCRT without ENI. Hilar and mediastinal nodal regions were contoured on planning CT. The prescription dose was normalized to 70 Gy. Equivalent uniform dose (EUD) and other dosimetric parameters (e.g., V 40 ) were calculated for each nodal station. Results: The median EUD for the whole group ranged from 0.4 to 4.4 Gy for all elective nodal regions. Gross tumor volume (GTV) and the relationship between GTV and hilum were significantly correlated with irradiation dose to ipsilateral hilar nodal regions (P 3 (diameter ∼ 4 cm) and or having any overlap with hilum, the median EUDs were 9.6, 22.6, and 62.9 Gy for ipsilateral lower paratracheal, subcarinal, and ipsilateral hilar regions, respectively. The corresponding median V 40 were 32.5%, 39.3%, and 97.6%, respectively. Conclusions: Although incidental nodal irradiation dose is low in the whole group, the dose to high-risk nodal regions is considerable in patients with T 1-3 N 0 NSCLC when the primary is large and/or centrally located

  2. Identifying Nodes of Transmission in Disease Diffusion Through Social Media

    Science.gov (United States)

    Lamb, David Sebastian

    The spread of infectious diseases can be described in terms of three interrelated components: interaction, movement, and scale. Transmission between individuals requires some form of interaction, which is dependent on the pathogen, to occur. Diseases spread through the movement of their hosts; they spread across many spatial scales from local neighborhoods to countries, or temporal scales from days to years, or periodic intervals. Prior research into the spread of disease have examined diffusion processes retrospectively at regional or country levels, or developed differential equation or simulation models of the dynamics of disease transmission. While some of the more recent models incorporate all three components, they are limited in the way they understand where interactions occur. The focus has been on home or work, including contact with family or coworkers. The models reflect a lack of knowledge about how transmissions are made at specific locations in time, so-called nodes of transmission. That is, how individuals' intersections in time and space function in disease transmission. This project sought to use the three factors of interaction, movement, and scale to better understand the spread of disease in terms of the place of interaction called the node of transmission. The overarching objective of this research was: how can nodes of transmission be identified through individual activity spaces incorporating the three factors of infectious disease spread: interaction, movement, and scale?. This objective fed into three main sub-objectives: defining nodes of transmission, developing an appropriate methodology to identifying nodes of transmission, and applying it using geotagged social media data from Twitter. To develop an appropriate framework, this research relied on time geography, and traditional disease. This particularly relied on the idea of bundling to create the nodes, and a nesting effect that integrated scale. The data source used to identify nodes

  3. Instant node package module

    CERN Document Server

    Ali, Juzer

    2013-01-01

    Get to grips with a new technology, understand what it is and what it can do for you, and then get to work with the most important features and tasks. A practical exploration of the lifecycle of creating node modules as well as learning all of the top features that npm has to offer.Intended for readers who want to create their first node.js modules. The programming paradigm of JavaScript is not covered so a foundation in these concepts would be beneficial.

  4. Anatomy and nomenclature of murine lymph nodes: Descriptive study and nomenclatory standardization in BALB/cAnNCrl mice.

    Science.gov (United States)

    Van den Broeck, Wim; Derore, Annie; Simoens, Paul

    2006-05-30

    Murine lymph nodes are intensively studied but often assigned incorrectly in scientific papers. In BALB/cAnNCrl mice, we characterized a total of 22 different lymph nodes. Peripheral nodes were situated in the head and neck region (mandibular, accessory mandibular, superficial parotid, cranial deep cervical nodes), and at the forelimb (proper axillary, accessory axillary nodes) and hindlimb (subiliac, sciatic, popliteal nodes). Intrathoracic lymph nodes included the cranial mediastinal, tracheobronchal and caudal mediastinal nodes. Abdominal lymph nodes were associated with the gastrointestinal tract (gastric, pancreaticoduodenal, jejunal, colic, caudal mesenteric nodes) or were located along the major intra-abdominal blood vessels (renal, lumbar aortic, lateral iliac, medial iliac and external iliac nodes). Comparative and nomenclative aspects of murine lymph nodes are discussed. The position of the lymph nodes of BALB/cAnNCrl mice is summarized and illustrated in an anatomical chart containing proposals for both an official nomenclature according to the Nomina Anatomica Veterinaria and English terms.

  5. Magnetization of topological line-node semimetals

    Science.gov (United States)

    Mikitik, G. P.; Sharlai, Yu. V.

    2018-02-01

    Using an approximate expression for the Landau levels of the electrons located near a nodal line of a topological line-node semimetal, we obtain formulas for the magnetization of this semimetal at an arbitrary shape of its line. It is also shown that the dependence of the chemical potential on the magnetic field can be strong in these materials, and this dependence can essentially influence the de Haas-van Alphen oscillations. The obtained results are applied to the rhombohedral graphite, which is one of the line-node semimetals. For this material, we find temperature and magnetic field dependencies of its magnetic susceptibility.

  6. Sheep lymph-nodes as a biological indicator of environmental exposure to fluoro-edenite

    International Nuclear Information System (INIS)

    Ledda, Caterina; Loreto, Carla; Pomara, Cristoforo; Rapisarda, Giuseppe; Fiore, Maria; Ferrante, Margherita; Bracci, Massimo; Santarelli, Lory; Fenga, Concettina; Rapisarda, Venerando

    2016-01-01

    A significantly increased incidence of pleural mesothelioma in Biancavilla (Sicily, Italy) has been attributed to exposure to fluoro-edenite (FE), a fibrous amphibole extracted from a local stone quarry. The lymph-nodes draining the pulmonary lobes of sheep grazing around the town were examined, to gain insights into fibre diffusion. The pasture areas of six sheep flocks lying about 3 km from Biancavilla were located using the global positioning system. The cranial tracheobronchial and one middle mediastinal lymph-node as well as four lung tissue samples were collected from 10 animals from each flock and from 10 control sheep for light and scanning electron microscopy (SEM) examination. The lymph-nodes from exposed sheep were enlarged and exhibited signs of anthracosis. Histologically, especially at the paracortical level, they showed lymph-follicle hyperplasia with large reactive cores and several macrophages (coniophages) containing grey-brownish particulate interspersed with elements with a fibril structure, forming aggregates of varying dimensions (coniophage nodules). Similar findings were detected in some peribronchiolar areas of the lung parenchyma. SEM examination showed that FE fibres measured 8–41 µm in length and 0.4–1.39 µm in diameter in both lymph-nodes and lung tissue. Monitoring of FE fibres in sheep lymph-nodes using appropriate techniques can help set up environmental pollution surveillance. - Highlights: • Lymph-nodes draining sheep lung were used to assess environmental fluoro-edenite exposure. • Monitoring fluoro-edenite fibres in sheep lung nodes can provide pollution surveillance. • Our findings document a risk of fluoro-edenite fibre inhalation a few kilometres from the source. • Sheep appear to be a valuable bioindicator species.

  7. Sheep lymph-nodes as a biological indicator of environmental exposure to fluoro-edenite

    Energy Technology Data Exchange (ETDEWEB)

    Ledda, Caterina, E-mail: cledda@unict.it [Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, Catania (Italy); Hygiene and Public Health, Department of Medical Sciences, Surgical and Advanced Technologies “GF Ingrassia”, University of Catania, Catania (Italy); Loreto, Carla [Human Anatomy and Histology, Department of Bio-Medical Sciences, University of Catania, Catania (Italy); Pomara, Cristoforo [Department of Anatomy, School of Medicine, University of Malta, Msida (Malta); Rapisarda, Giuseppe [Department of Veterinary Medicine, ASP Catania, Catania (Italy); Fiore, Maria; Ferrante, Margherita [Hygiene and Public Health, Department of Medical Sciences, Surgical and Advanced Technologies “GF Ingrassia”, University of Catania, Catania (Italy); Bracci, Massimo; Santarelli, Lory [Occupational Medicine, Department of Clinical and Molecular Sciences, Polytechnic University of Marche, Ancona (Italy); Fenga, Concettina [Occupational Medicine, Department of the Environment, Safety, Territory, Food and Health Sciences, University of Messina, Messina (Italy); Rapisarda, Venerando [Occupational Medicine, Department of Clinical and Experimental Medicine, University of Catania, Catania (Italy)

    2016-05-15

    A significantly increased incidence of pleural mesothelioma in Biancavilla (Sicily, Italy) has been attributed to exposure to fluoro-edenite (FE), a fibrous amphibole extracted from a local stone quarry. The lymph-nodes draining the pulmonary lobes of sheep grazing around the town were examined, to gain insights into fibre diffusion. The pasture areas of six sheep flocks lying about 3 km from Biancavilla were located using the global positioning system. The cranial tracheobronchial and one middle mediastinal lymph-node as well as four lung tissue samples were collected from 10 animals from each flock and from 10 control sheep for light and scanning electron microscopy (SEM) examination. The lymph-nodes from exposed sheep were enlarged and exhibited signs of anthracosis. Histologically, especially at the paracortical level, they showed lymph-follicle hyperplasia with large reactive cores and several macrophages (coniophages) containing grey-brownish particulate interspersed with elements with a fibril structure, forming aggregates of varying dimensions (coniophage nodules). Similar findings were detected in some peribronchiolar areas of the lung parenchyma. SEM examination showed that FE fibres measured 8–41 µm in length and 0.4–1.39 µm in diameter in both lymph-nodes and lung tissue. Monitoring of FE fibres in sheep lymph-nodes using appropriate techniques can help set up environmental pollution surveillance. - Highlights: • Lymph-nodes draining sheep lung were used to assess environmental fluoro-edenite exposure. • Monitoring fluoro-edenite fibres in sheep lung nodes can provide pollution surveillance. • Our findings document a risk of fluoro-edenite fibre inhalation a few kilometres from the source. • Sheep appear to be a valuable bioindicator species.

  8. The Use of LiDAR Elevation Data and Satellite Imagery to Locate Critical Source Areas to Diffuse Pollution in Agricultural Watersheds

    Science.gov (United States)

    Drouin, Ariane; Michaud, Aubert; Thériault, Georges; Beaudin, Isabelle; Rodrigue, Jean-François; Denault, Jean-Thomas; Desjardins, Jacques; Côté, Noémi

    2013-04-01

    In Quebec / Canada, water quality improvement in rural areas greatly depends on the reduction of diffuse pollution. Indeed, point source pollution has been reduced significantly in Canada in recent years by creating circumscribed pits for manure and removing animals from stream. Diffuse pollution differs from point source pollution because it is spread over large areas. In agricultural areas, sediment loss by soil and riverbank erosion along with loss of nutrients (phosphorus, nitrogen, etc.) and pesticides from fields represent the main source of non-point source pollution. The factor mainly responsible for diffuse pollution in agricultural areas is surface runoff occurring in poorly drained areas in fields. The presence of these poorly drained areas is also one of the most limiting factors in crop productivity. Thus, a reconciliation of objectives at the farm (financial concern for farmers) and off-farm concerns (environmental concern) is possible. In short, drainage, runoff, erosion, water quality and crop production are all interconnected issues that need to be tackled together. Two complementary data sources are mainly used in the diagnosis of drainage, surface runoff and erosion : elevation data and multispectral satellite images. In this study of two watersheds located in Québec (Canada), LiDAR elevation data and satellite imagery (QuickBird, Spot and Landsat) were acquired. The studied territories have been partitioned in hydrologic response units (HRUs) according to sub-basins, soils, elevation (topographic index) and land use. These HRUs are afterwards used in a P index software (P-Edit) that calculates the quantities of sediments and phosphorus exported from each HRUs. These exports of sediments and phosphorus are validated with hydrometric and water quality data obtain in two sub-basins and are also compared to soil brightness index derived from multispectral images. This index is sensitive to soil moisture and thus highlights areas where the soil is

  9. Locating S-wave sources for the SPE-5 explosion using time reversal methods and a close-in, 1000 sensor network

    Science.gov (United States)

    Myers, S. C.; Pitarka, A.; Mellors, R. J.

    2016-12-01

    The Source Physics Experiment (SPE) is producing new data to study the generation of seismic waves from explosive sources. Preliminary results show that far-field S-waves are generated both within the non-elastic volume surrounding explosive sources and by P- to S-wave scattering. The relative contribution of non-elastic phenomenology and elastic-wave scattering to far-field S-waves has been debated for decades, and numerical simulations based on the SPE experiments are addressing this question. The match between observed and simulated data degrades with event-station distance and with increasing time in each seismogram. This suggests that a more accurate model of subsurface elastic properties could result in better agreement between observed and simulated seismograms. A detailed model of subsurface structure has been developed using geologic maps and the extensive database of borehole logs, but uncertainty in structural details remains high. The large N instrument deployment during the SPE-5 experiment offers an opportunity to use time-reversal techniques to back project the wave field into the subsurface to locate significant sources of scattered energy. The large N deployment was nominally 1000, 5 Hz sensors (500 Z and 500 3C geophones) deployed in a roughly rectangular array to the south and east of the SPE-5 shot. Sensor spacing was nominally 50 meters in the interior portion of the array and 100 meters in the outer region, with two dense lines at 25 m spacing. The array covers the major geologic boundary between the Yucca Flat basin and the granitic Climax Stock in which the SPE experiments have been conducted. Improved mapping of subsurface scatterers is expected to result in better agreement between simulated and observed seismograms and aid in our understanding of S-wave generation from explosions. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344.

  10. Location-Aided Reliable Routing for Opportunistic Networks

    Institute of Scientific and Technical Information of China (English)

    Yong Yang; Zhi Ren; Jibi Li

    2012-01-01

    In our study, we investigate the problem of location-based routing in opportunistic networks. Due to the uncertainty of end-to-end paths between sources and destinations, the classical location-based ad hoc routing protocols cannot adapt to the environment of opportunistic networks, which leads to the decrease of the delivery rate of data. To address it, we propose in this paper a novel location-aided routing protocol which is suitable for opportunistic networks. In our protocol, a node can send location information on demand by using prediction mechanism, and when sending a data packet, the node chooses multiple neighbors which are closer to the destination as next hops. If the candidate neighbors do not exist, the node carries the data till it meets a proper neighbor or the destination. Theoretical analysis and simulation results show that our proposed protocol outperforms DREAM (Distance Routing Effect Protocol Mobility) and one of its improved versions, BFDREAM (Boundary Forwarding DREAM), in terms of the delivery rate and overhead.

  11. Partial axillary lymph node dissection inferior to the intercostobrachial nerves complements sentinel node biopsy in patients with clinically node-negative breast cancer.

    Science.gov (United States)

    Li, Jianyi; Jia, Shi; Zhang, Wenhai; Qiu, Fang; Zhang, Yang; Gu, Xi; Xue, Jinqi

    2015-06-30

    The practice of breast cancer diagnosis and treatment in China varies to that in western developed countries. With the unavailability of radioactive tracer technique for sentinel lymph nodes biopsy (SLNB), using blue dye alone has been the only option in China. Also, the diagnosis of breast malignant tumor in most Chinese centres heavily relies on intraoperative instant frozen histology which is normally followed by sentinel lymph nodes mapping, SLNB and the potential breast and axillary operations in one consecutive session. This practice appears to cause a high false negative rate (FNR) for SLNB. The present study aimed to investigate the impact of the current practice in China on the accuracy of SLNB, and whether partial axillary lymph node dissection (PALND), dissection of lymph nodes inferior to the intercostobrachial nerve (ICBN), was a good complementary procedure following SLNB using blue dye. 289 patients with clinically node-negative breast cancer were identified and recruited. Tumorectomy, intraoperative instant frozen histological diagnosis, SLNB using methylene blue dye, and PALND or complete axillary node dissection (ALND) were performed in one consecutive operative session. The choice of SLNB only, SLNB followed by PALND or by ALND was based on the pre-determined protocol and preoperative choice by the patient. Clinical parameters were analyzed and survival analysis was performed. 37% patients with clinically negative nodes were found nodes positive. 59 patients with positive SLN underwent ALND, including 47 patients with up to two positive nodes which were all located inferior to the ICBN. 9 patients had failed SLNB and underwent PALND. Among them, 3 (33.3%) patients were found to have one metastatic node. 149 patients showed negative SLNB but chose PALND. Among them, 30 (20.1%), 14 (9.4) and 1 (0.7%) patients were found to have one, two and three metastatic node(s), respectively. PALND detected 48 (30.4%) patients who had either failed SLNB or

  12. Integrating cut-and-solve and semi-Lagrangean based dual ascent for the single-source capacitated facility location problem

    DEFF Research Database (Denmark)

    Gadegaard, Sune Lauth

    polytope with generalized upper bounds. From our computational study, we show that the semi-Lagrangean relaxation approach has its merits when the instances are tightly constrained with regards to the capacity of the system, but that it is very hard to compete with a standalone implementation of the cut......This paper describes how the cut-and-solve framework and semi-Lagrangean based dual ascent algorithms can be integrated in two natural ways in order to solve the single source capacitated facility location problem. The first uses the cut-and-solve framework both as a heuristic and as an exact...... solver for the semi-Lagrangean subproblems. The other uses a semi-Lagrangean based dual ascent algorithm to solve the sparse problems arising in the cut-and-solve algorithm. Furthermore, we developed a simple way to separate a special type of cutting planes from what we denote the effective capacity...

  13. Error Control in Distributed Node Self-Localization

    Directory of Open Access Journals (Sweden)

    Ying Zhang

    2008-03-01

    Full Text Available Location information of nodes in an ad hoc sensor network is essential to many tasks such as routing, cooperative sensing, and service delivery. Distributed node self-localization is lightweight and requires little communication overhead, but often suffers from the adverse effects of error propagation. Unlike other localization papers which focus on designing elaborate localization algorithms, this paper takes a different perspective, focusing on the error propagation problem, addressing questions such as where localization error comes from and how it propagates from node to node. To prevent error from propagating and accumulating, we develop an error-control mechanism based on characterization of node uncertainties and discrimination between neighboring nodes. The error-control mechanism uses only local knowledge and is fully decentralized. Simulation results have shown that the active selection strategy significantly mitigates the effect of error propagation for both range and directional sensors. It greatly improves localization accuracy and robustness.

  14. A Location Intelligence System for the Assessment of Pluvial Flooding Risk and the Identification of Storm Water Pollutant Sources from Roads in Suburbanised Areas

    Directory of Open Access Journals (Sweden)

    Szymon Szewrański

    2018-06-01

    Full Text Available The interplay of an ever-growing number of inhabitants, sprawl development, soil sealing, changes in urban traffic characteristics, as well as observed climate trends gives rise to more frequent pluvial flooding in cities, a higher run-off of water, and an increasing pollution of surface water. The aim of this research is to develop a location intelligence system for the assessment of pluvial flooding risks and the identification of storm water pollutant sources from roads in newly-developed areas. The system combines geographic information systems and business intelligence software, and it is based on the original Pluvial Flood Risk Assessment tool. The location intelligence system effectively identifies the spatial and temporal distribution of pluvial flood risks, allows to preliminarily evaluate the total run-off from roads, and helps localise potential places for new water management infrastructure. Further improvements concern the modelling of a flow accumulation and drainage system, the application of weather radar precipitation data, and traffic monitoring and modelling.

  15. Wireless Sensor Networks - Node Localization for Various Industry Problems

    International Nuclear Information System (INIS)

    Derr, Kurt; Manic, Milos

    2015-01-01

    Fast, effective monitoring following airborne releases of toxic substances is critical to mitigate risks to threatened population areas. Wireless sensor nodes at fixed predetermined locations may monitor such airborne releases and provide early warnings to the public. A challenging algorithmic problem is determining the locations to place these sensor nodes while meeting several criteria: 1) provide complete coverage of the domain, and 2) create a topology with problem dependent node densities, while 3) minimizing the number of sensor nodes. This manuscript presents a novel approach to determining optimal sensor placement, Advancing Front mEsh generation with Constrained dElaunay Triangulation and Smoothing (AFECETS) that addresses these criteria. A unique aspect of AFECETS is the ability to determine wireless sensor node locations for areas of high interest (hospitals, schools, high population density areas) that require higher density of nodes for monitoring environmental conditions, a feature that is difficult to find in other research work. The AFECETS algorithm was tested on several arbitrary shaped domains. AFECETS simulation results show that the algorithm 1) provides significant reduction in the number of nodes, in some cases over 40%, compared to an advancing front mesh generation algorithm, 2) maintains and improves optimal spacing between nodes, and 3) produces simulation run times suitable for real-time applications

  16. Source contributions to PM{sub 2.5} and PM{sub 10} at an urban background and a street location

    Energy Technology Data Exchange (ETDEWEB)

    Keuken, M.; Voogt, M.; Moerman, M. [TNO, Utrecht (Netherlands); Blom, M.; Weijers, E.P. [Energy research Centre of the Netherlands ECN, Petten (Netherlands); Roeckmann, T.; Dusek, U. [Institute for Marine and Atmospheric Research IMAU, Utrecht (Netherlands)

    2013-06-15

    The contribution of regional, urban and traffic sources to PM{sub 2.5} and PM{sub 10} in an urban area was investigated in this study. The chemical composition of PM{sub 2.5} and PM{sub 10} was measured over a year at a street location and up- and down-wind of the city of Rotterdam, Netherlands. The {sup 14}C content in EC and OC concentrations was also determined, to distinguish the contribution from 'modern' carbon (e.g., biogenic emissions, biomass burning and wildfires) and fossil fuel combustion. It was concluded that the urban background of PM{sub 2.5} and PM{sub 10} is dominated by the regional background, and that primary and secondary PM emission by urban sources contribute less than 15%. The {sup 14}C analysis revealed that 70% of OC originates from modern carbon and 30% from fossil fuel combustion. The corresponding percentages for EC are, respectively 17% and 83%. It is concluded that in particular the urban population living in street canyons with intense road traffic has potential health risks. This is due to exposure to elevated concentrations of a factor two for EC from exhaust emissions in PM{sub 2.5} and a factor 2-3 for heavy metals from brake and tyre wear, and re-suspended road dust in PM{sub 10}. It follows that local air quality management may focus on local measures to street canyons with intense road traffic.

  17. Sentinel nodes identified by computed tomography-lymphography accurately stage the axilla in patients with breast cancer

    International Nuclear Information System (INIS)

    Motomura, Kazuyoshi; Sumino, Hiroshi; Noguchi, Atsushi; Horinouchi, Takashi; Nakanishi, Katsuyuki

    2013-01-01

    Sentinel node biopsy often results in the identification and removal of multiple nodes as sentinel nodes, although most of these nodes could be non-sentinel nodes. This study investigated whether computed tomography-lymphography (CT-LG) can distinguish sentinel nodes from non-sentinel nodes and whether sentinel nodes identified by CT-LG can accurately stage the axilla in patients with breast cancer. This study included 184 patients with breast cancer and clinically negative nodes. Contrast agent was injected interstitially. The location of sentinel nodes was marked on the skin surface using a CT laser light navigator system. Lymph nodes located just under the marks were first removed as sentinel nodes. Then, all dyed nodes or all hot nodes were removed. The mean number of sentinel nodes identified by CT-LG was significantly lower than that of dyed and/or hot nodes removed (1.1 vs 1.8, p <0.0001). Twenty-three (12.5%) patients had ≥2 sentinel nodes identified by CT-LG removed, whereas 94 (51.1%) of patients had ≥2 dyed and/or hot nodes removed (p <0.0001). Pathological evaluation demonstrated that 47 (25.5%) of 184 patients had metastasis to at least one node. All 47 patients demonstrated metastases to at least one of the sentinel nodes identified by CT-LG. CT-LG can distinguish sentinel nodes from non-sentinel nodes, and sentinel nodes identified by CT-LG can accurately stage the axilla in patients with breast cancer. Successful identification of sentinel nodes using CT-LG may facilitate image-based diagnosis of metastasis, possibly leading to the omission of sentinel node biopsy

  18. Geographically Locating an Internet Node Using Network Latency Measurement

    National Research Council Canada - National Science Library

    Turnbaugh, Eugene

    2004-01-01

    .... The difficulties include accurate latency measure, network address translation (NAT) masking, service blocking, disparate physical configuration, dissimilar network hardware, and inaccurate and limited measuring tools...

  19. Characterization and treatment of water used for human consumption from six sources located in the Cameron/Tuba City abandoned uranium mining area.

    Science.gov (United States)

    Orescanin, Visnja; Kollar, Robert; Nad, Karlo; Mikelic, Ivanka Lovrencic; Kollar, Iris

    2011-01-01

    The purpose of this research was the characterization and improvement of the quality of water used for human consumption of unregulated/regulated water sources located in the Cameron/Tuba City abandoned uranium mining area (NE Arizona, western edge of the Navajo Nation). Samples were collected at six water sources which included regulated sources: Wind Mill (Tank 3T-538), Badger Springs and Paddock Well as well as unregulated sources: Willy Spring, Water Wall and Water Hole. Samples taken from Wind Mill, Water Wall and Water Hole were characterized with high turbidity and color as well as high level of manganese, iron and nickel and elevated value of molybdenum. High level of iron was also found in Badger Spring, Willy Spring, and Paddock Well. These three water sources were also characterized with elevated values of fluoride and vanadium. Significant amounts of zinc were found in Water Wall and Water Hole samples. Water Wall sample was also characterized with high level of Cr(VI). Compared to primary or secondary Navajo Nation Environmental Protection Agency (NNEPA) water quality standard the highest enrichment was found for turbidity (50.000 times), color (up to 1.796 times) and manganese (71 times), Cr(VI) (17.5 times), iron (7.4 times) and arsenic (5.2 times). Activities of (226)Ra and (238)U in water samples were still in agreement with the maximum contaminant levels. In order to comply with NNEPA water quality standard water samples were subjected to electrochemical treatment. This method was selected due to its high removal efficiency for heavy metals and uranium, lower settlement time, production of smaller volume of waste mud and higher stability of waste mud compared to physico-chemical treatment. Following the treatment, concentrations of heavy metals and activities of radionuclides in all samples were significantly lower compared to NNEPA or WHO regulated values. The maximum removal efficiencies for color, turbidity, arsenic, manganese, molybdenum and

  20. Involved Node Radiation Therapy

    DEFF Research Database (Denmark)

    Maraldo, Maja V; Aznar, Marianne C; Vogelius, Ivan R

    2012-01-01

    PURPOSE: The involved node radiation therapy (INRT) strategy was introduced for patients with Hodgkin lymphoma (HL) to reduce the risk of late effects. With INRT, only the originally involved lymph nodes are irradiated. We present treatment outcome in a retrospective analysis using this strategy...... to 36 Gy). Patients attended regular follow-up visits until 5 years after therapy. RESULTS: The 4-year freedom from disease progression was 96.4% (95% confidence interval: 92.4%-100.4%), median follow-up of 50 months (range: 4-71 months). Three relapses occurred: 2 within the previous radiation field......, and 1 in a previously uninvolved region. The 4-year overall survival was 94% (95% confidence interval: 88.8%-99.1%), median follow-up of 58 months (range: 4-91 months). Early radiation therapy toxicity was limited to grade 1 (23.4%) and grade 2 (13.8%). During follow-up, 8 patients died, none from HL, 7...

  1. One node driving synchronisation

    Science.gov (United States)

    Wang, Chengwei; Grebogi, Celso; Baptista, Murilo S.

    2015-12-01

    Abrupt changes of behaviour in complex networks can be triggered by a single node. This work describes the dynamical fundamentals of how the behaviour of one node affects the whole network formed by coupled phase-oscillators with heterogeneous coupling strengths. The synchronisation of phase-oscillators is independent of the distribution of the natural frequencies, weakly depends on the network size, but highly depends on only one key oscillator whose ratio between its natural frequency in a rotating frame and its coupling strength is maximum. This result is based on a novel method to calculate the critical coupling strength with which the phase-oscillators emerge into frequency synchronisation. In addition, we put forward an analytical method to approximately calculate the phase-angles for the synchronous oscillators.

  2. Accumulations and sources of uranium, of its daughters and of metallic trace elements in wetlands located around old uranium mining sites

    International Nuclear Information System (INIS)

    Cuvier, Alicia

    2015-01-01

    Uranium mining and uranium ore processing increase the environmental activity of U and Th decay products and trace elements, in particular in case of releases to the adjacent rivers. Contaminants accumulate then preferentially in sedimentation areas (such as ponds or lakes) or in wetlands (peat lands, marshes or riverbanks) located downstream to the mine. Wetlands - generally located at the head of watershed - are particularly sensitive to environmental changes and anthropogenic pressure. This poses a risk of release of contaminants from these accumulation areas. The objective of the present study is to propose an easily reproducible methodology - in particular for the orphan mining sites - to identify and characterize accumulation areas. This study also aims to improve our understanding of the mechanisms of accumulation and release, in these areas. This study was performed around the former mining site of Bertholene (France). Standing and mobile in situ gamma spectrometry is used to accurately locate the accumulation areas. Soils, sediments, vegetation, water and peat are also sampled upstream and downstream of the mine, in order to (a) characterize the activities and the disequilibria of the U-Th decay chains and the associated trace elements according to the scale of observation, (b) understand the mechanisms of accumulation and release and (c) identify the potential sources using geochemical proxies and isotopic analyses. The results obtained show that radionuclides are mainly accumulated in a flooding area located downstream the mine. Strong U-238 activities (≥ 20000 Bq.kg"-"1) and strong Ra-226/U-238 and Th-230/Ra-226 activity ratios are recorded, involving preferential inputs of U-238 and Th-230 during flooding events. Trace element contamination is low, except for Mn, Ba and S. Such contaminations are potentially explained by the geochemical composition of the uranium ore and by the past and current processes of ore and water mine. Sequential extractions

  3. Node web development

    CERN Document Server

    Herron, David

    2013-01-01

    Presented in a simple, step-by-step format, this book is an introduction to web development with Node.This book is for anybody looking for an alternative to the ""P"" languages (Perl, PHP, Python), or anyone looking for a new paradigm of server-side application development.The reader should have at least a rudimentary understanding of JavaScript and web application development.

  4. Cellular Phone Towers, Cell tower locations as derived from various sources including the Department of Licenses and Inspections and the Department of Planning and Zoning., Published in 2010, 1:2400 (1in=200ft) scale, Howard County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Cellular Phone Towers dataset current as of 2010. Cell tower locations as derived from various sources including the Department of Licenses and Inspections and the...

  5. Status of lymph node staging

    NARCIS (Netherlands)

    Nieweg, O. E.; Estourgie, S. H.; Deurloo, E. E.; Rutgers, E. J. Th; Kroon, B. B. R.

    2002-01-01

    Sentinel node biopsy has the potential to provide more accurate staging information than axillary node dissection. Given the considerable morbidity of axillary node dissection this less invasive approach is attractive. However, there are a number of issues to be resolved before the best technique of

  6. Strength Restoration of Cracked Sandstone and Coal under a Uniaxial Compression Test and Correlated Damage Source Location Based on Acoustic Emissions

    Science.gov (United States)

    Feng, Xiaowei; Zhang, Nong; Zheng, Xigui; Pan, Dongjiang

    2015-01-01

    Underground rock masses have shown a general trend of natural balance over billions of years of ground movement. Nonetheless, man-made underground constructions disturb this balance and cause rock stability failure. Fractured rock masses are frequently encountered in underground constructions, and this study aims to restore the strength of rock masses that have experienced considerable fracturing under uniaxial compression. Coal and sandstone from a deep-buried coal mine were chosen as experimental subjects; they were crushed by uniaxial compression and then carefully restored by a chemical adhesive called MEYCO 364 with an innovative self-made device. Finally, the restored specimens were crushed once again by uniaxial compression. Axial stress, axial strain, circumferential strain, and volumetric strain data for the entire process were fully captured and are discussed here. An acoustic emission (AE) testing system was adopted to cooperate with the uniaxial compression system to provide better definitions for crack closure thresholds, crack initiation thresholds, crack damage thresholds, and three-dimensional damage source locations in intact and restored specimens. Several remarkable findings were obtained. The restoration effects of coal are considerably better than those of sandstone because the strength recovery coefficient of the former is 1.20, whereas that of the latter is 0.33, which indicates that MEYCO 364 is particularly valid for fractured rocks whose initial intact peak stress is less than that of MEYCO 364. Secondary cracked traces of restored sandstone almost follow the cracked traces of the initial intact sandstone, and the final failure is mainly caused by decoupling between the adhesive and the rock mass. However, cracked traces of restored coal only partially follow the traces of intact coal, with the final failure of the restored coal being caused by both bonding interface decoupling and self-breakage in coal. Three-dimensional damage source

  7. Strength Restoration of Cracked Sandstone and Coal under a Uniaxial Compression Test and Correlated Damage Source Location Based on Acoustic Emissions.

    Directory of Open Access Journals (Sweden)

    Xiaowei Feng

    Full Text Available Underground rock masses have shown a general trend of natural balance over billions of years of ground movement. Nonetheless, man-made underground constructions disturb this balance and cause rock stability failure. Fractured rock masses are frequently encountered in underground constructions, and this study aims to restore the strength of rock masses that have experienced considerable fracturing under uniaxial compression. Coal and sandstone from a deep-buried coal mine were chosen as experimental subjects; they were crushed by uniaxial compression and then carefully restored by a chemical adhesive called MEYCO 364 with an innovative self-made device. Finally, the restored specimens were crushed once again by uniaxial compression. Axial stress, axial strain, circumferential strain, and volumetric strain data for the entire process were fully captured and are discussed here. An acoustic emission (AE testing system was adopted to cooperate with the uniaxial compression system to provide better definitions for crack closure thresholds, crack initiation thresholds, crack damage thresholds, and three-dimensional damage source locations in intact and restored specimens. Several remarkable findings were obtained. The restoration effects of coal are considerably better than those of sandstone because the strength recovery coefficient of the former is 1.20, whereas that of the latter is 0.33, which indicates that MEYCO 364 is particularly valid for fractured rocks whose initial intact peak stress is less than that of MEYCO 364. Secondary cracked traces of restored sandstone almost follow the cracked traces of the initial intact sandstone, and the final failure is mainly caused by decoupling between the adhesive and the rock mass. However, cracked traces of restored coal only partially follow the traces of intact coal, with the final failure of the restored coal being caused by both bonding interface decoupling and self-breakage in coal. Three

  8. Sources

    International Nuclear Information System (INIS)

    Duffy, L.P.

    1991-01-01

    This paper discusses the sources of radiation in the narrow perspective of radioactivity and the even narrow perspective of those sources that concern environmental management and restoration activities at DOE facilities, as well as a few related sources. Sources of irritation, Sources of inflammatory jingoism, and Sources of information. First, the sources of irritation fall into three categories: No reliable scientific ombudsman to speak without bias and prejudice for the public good, Technical jargon with unclear definitions exists within the radioactive nomenclature, and Scientific community keeps a low-profile with regard to public information. The next area of personal concern are the sources of inflammation. This include such things as: Plutonium being described as the most dangerous substance known to man, The amount of plutonium required to make a bomb, Talk of transuranic waste containing plutonium and its health affects, TMI-2 and Chernobyl being described as Siamese twins, Inadequate information on low-level disposal sites and current regulatory requirements under 10 CFR 61, Enhanced engineered waste disposal not being presented to the public accurately. Numerous sources of disinformation regarding low level radiation high-level radiation, Elusive nature of the scientific community, The Federal and State Health Agencies resources to address comparative risk, and Regulatory agencies speaking out without the support of the scientific community

  9. Two Phases Authentication Level (TPAL) protocol for nodes ...

    African Journals Online (AJOL)

    ... node may contain sensitive informations such as military data and monitoring data. ... LLN is a kind of Internet of Things (IoT) network with limited power source ... Current authentication Internet protocols cannot be adopted directly into LLN ...

  10. Locative media

    CERN Document Server

    Wilken, Rowan

    2014-01-01

    Not only is locative media one of the fastest growing areas in digital technology, but questions of location and location-awareness are increasingly central to our contemporary engagements with online and mobile media, and indeed media and culture generally. This volume is a comprehensive account of the various location-based technologies, services, applications, and cultures, as media, with an aim to identify, inventory, explore, and critique their cultural, economic, political, social, and policy dimensions internationally. In particular, the collection is organized around the perception that the growth of locative media gives rise to a number of crucial questions concerning the areas of culture, economy, and policy.

  11. Maximizing Lifetime of Wireless Sensor Networks with Mobile Sink Nodes

    Directory of Open Access Journals (Sweden)

    Yourong Chen

    2014-01-01

    Full Text Available In order to maximize network lifetime and balance energy consumption when sink nodes can move, maximizing lifetime of wireless sensor networks with mobile sink nodes (MLMS is researched. The movement path selection method of sink nodes is proposed. Modified subtractive clustering method, k-means method, and nearest neighbor interpolation method are used to obtain the movement paths. The lifetime optimization model is established under flow constraint, energy consumption constraint, link transmission constraint, and other constraints. The model is solved from the perspective of static and mobile data gathering of sink nodes. Subgradient method is used to solve the lifetime optimization model when one sink node stays at one anchor location. Geometric method is used to evaluate the amount of gathering data when sink nodes are moving. Finally, all sensor nodes transmit data according to the optimal data transmission scheme. Sink nodes gather the data along the shortest movement paths. Simulation results show that MLMS can prolong network lifetime, balance node energy consumption, and reduce data gathering latency under appropriate parameters. Under certain conditions, it outperforms Ratio_w, TPGF, RCC, and GRND.

  12. On the question of 3D seed reconstruction in prostate brachytherapy: the determination of x-ray source and film locations

    International Nuclear Information System (INIS)

    Zhang Mutian; Zaider, Marco; Worman, Michael; Cohen, Gilad

    2004-01-01

    Inaccuracy in seed placement during permanent prostate implants may lead to significant dosimetric deviations from the intended plan. In two recent publications (Todor et al 2002 Phys. Med. Biol. 47 2031-48, Todor et al 2003 Phys. Med. Biol. 48 1153-71), methodology was described for identifying intraoperatively the positions of seeds already implanted, thus allowing re-optimization of the treatment plan and correcting for such seed misplacement. Seed reconstruction is performed using fluoroscopic images and an important (and non-trivial) component of this approach is the ability to accurately determine the position of the gantry relative to the treatment volume. We describe the methodology for acquiring this information, based on the known geometry of six markers attached to the ultrasound probe. This method does not require the C-arm unit to be isocentric and films can be taken with the gantry set at any arbitrary position. This is significant because the patient positioning on the operating table (in the lithotomy position) restricts the range of angles at which films can be taken to a quite narrow (typically ±10 0 ) interval and, as a general rule, the closer the angles the larger the uncertainty in the seed location reconstruction along the direction from the x-ray source to the film. (note)

  13. Subcarinal lymph node in upper lobe non-small cell lung cancer patients: is selective lymph node dissection valid?

    Science.gov (United States)

    Aokage, Keiju; Yoshida, Junji; Ishii, Genichiro; Hishida, Tomoyuki; Nishimura, Mitsuyo; Nagai, Kanji

    2010-11-01

    Little is known about selective lymph node dissection in non-small cell lung cancer (NSCLC) patients. We sought to gain insight into subcarinal node involvement for its frequency and impact on outcome to evaluate whether it is valid to omit subcarinal lymph node dissection in upper lobe NSCLC patients. We reviewed node metastases distribution according to node region, tumor location, and histology among 1099 patients with upper lobe NSCLC. We paid special attention to subcarinal metastases patients without superior mediastinal node metastases, because their pathological stages would have been underdiagnosed if subcarinal node dissection had been omitted. We also assessed the outcome and the pattern of failure among subcarinal metastases patients. To identify subcarinal node involvement predictors, we analyzed 7 clinical factors. Subcarinal node metastases were found in 20 patients and were least frequent among squamous cell carcinoma patients (0.5%). Two of them were free from superior mediastinal metastases but died of the disease at 1 month and due to an unknown cause at 18 months, respectively. Seventeen of the 20 patients developed multi-site recurrence within 37 months. The 5-year survival rate of the 20 patients with subcarinal metastases was 9.0%, which was significantly lower than 32.0% of patients with only superior mediastinal metastases. Clinical diagnosis of node metastases was significantly predictive of subcarinal metastases. Subcarinal node metastases from upper lobe NSCLC were rare and predicted an extremely poor outcome. It appears valid to omit subcarinal node dissection in upper lobe NSCLC patients, especially in clinical N0 squamous cell carcinoma patients. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  14. Location, location, location: Extracting location value from house prices

    OpenAIRE

    Kolbe, Jens; Schulz, Rainer; Wersing, Martin; Werwatz, Axel

    2012-01-01

    The price for a single-family house depends both on the characteristics of the building and on its location. We propose a novel semiparametric method to extract location values from house prices. After splitting house prices into building and land components, location values are estimated with adaptive weight smoothing. The adaptive estimator requires neither strong smoothness assumptions nor local symmetry. We apply the method to house transactions from Berlin, Germany. The estimated surface...

  15. sources

    Directory of Open Access Journals (Sweden)

    Shu-Yin Chiang

    2002-01-01

    Full Text Available In this paper, we study the simplified models of the ATM (Asynchronous Transfer Mode multiplexer network with Bernoulli random traffic sources. Based on the model, the performance measures are analyzed by the different output service schemes.

  16. The spreading of opposite opinions on online social networks with authoritative nodes

    Science.gov (United States)

    Yan, Shu; Tang, Shaoting; Pei, Sen; Jiang, Shijin; Zhang, Xiao; Ding, Wenrui; Zheng, Zhiming

    2013-09-01

    The study of opinion dynamics, such as spreading and controlling of rumors, has become an important issue on social networks. Numerous models have been devised to describe this process, including epidemic models and spin models, which mainly focus on how opinions spread and interact with each other, respectively. In this paper, we propose a model that combines the spreading stage and the interaction stage for opinions to illustrate the process of dispelling a rumor. Moreover, we set up authoritative nodes, which disseminate positive opinion to counterbalance the negative opinion prevailing on online social networking sites. With analysis of the relationship among positive opinion proportion, opinion strength and the density of authoritative nodes in networks with different topologies, we demonstrate that the positive opinion proportion grows with the density of authoritative nodes until the positive opinion prevails in the entire network. In particular, the relationship is linear in homogeneous topologies. Besides, it is also noteworthy that initial locations of the negative opinion source and authoritative nodes do not influence positive opinion proportion in homogeneous networks but have a significant impact on heterogeneous networks. The results are verified by numerical simulations and are helpful to understand the mechanism of two different opinions interacting with each other on online social networking sites.

  17. Spinal Schmorl's nodes: Sagittal sectional imaging and pathological examination

    International Nuclear Information System (INIS)

    Silberstein, M.; Opeskin, K.

    1999-01-01

    The presence, location and number of Schmorl's nodes was determined in the thoracolumbar spines of 70 motor vehicle accident victims using radiographic examination of a midline sagittal section and subsequent pathological examinations, including histology. In 28% of spines, a greater number of Schmorl's nodes were identified with radiography, while in 44%, pathological examination revealed a greater number of nodes. The visibility of Schmorl's nodes was enhanced by using a sagittal radiographic approach, and, in contrast to previous work, nodes below 0.5 cm 2 were readily detected. The results of the present study offer an additional imaging technique for postmortem analysis of the spine, and support the use of sagittal MR imaging for the evaluation of this condition. Copyright (1999) Blackwell Science Pty Ltd

  18. Chemical characterisation and source apportionment of PM1 during massive loading at an urban location in Indo-Gangetic Plain: impact of local sources and long-range transport

    Directory of Open Access Journals (Sweden)

    Prashant Rajput

    2016-07-01

    Full Text Available This study assesses temporal variability and source contributions of PM1 (particles with aerodynamic diameter ≤ 1.0 µm samples (n=51; November 2009–February 2010 from an urban location at Kanpur (26.30°N; 80.13°E; 142 m above mean sea-level in the Indo-Gangetic Plain (IGP. A study period from November to February is preferred owing to massive loading of particulate matter in entire IGP. PM1 varies from 18 to 348 (Avg±SD: 113±72 µg m−3 in this study. A total of 11 trace metals, five major elements and four water-soluble inorganic species (WSIS have been measured. Mass fraction of total metals (∑metals=trace+major centres at 18±14 %, of which nearly 15 % is contributed by major elements. Furthermore, ∑WSIS contributes about 26 % to PM1 mass concentration. Abundance pattern among assessed WSIS in this study follows the order: ≈> > Cl−. The K-to-PM1 mass fraction (Avg: 2 % in conjunction with air-mass back trajectories (AMBT indicates that the prevailing north-westerly winds transport biomass burning derived pollutants from upwind IGP. A recent version of positive matrix factorisation (PMF 5.0 has been utilised to quantify the contribution of fine-mode aerosols from various sources. The contribution from each source is highly variable and shows a strong dependence on AMBT. Events with predominant contribution from biomass burning emission (>70 % indicate origin of air-masses from source region upwind in IGP. One of the most interesting features of our study relates to the observation that secondary aerosols (contributing as high as ~60 % to PM1 loading are predominantly derived from stationary combustion sources (/ ratio: 0.30±0.23. Thus, our study highlights a high concentration of PM1 loading and atmospheric fog prevalent during wintertime can have a severe impact on atmospheric chemistry in the air-shed of IGP.

  19. Improvement In MAODV Protocol Using Location Based Routing Protocol

    Directory of Open Access Journals (Sweden)

    Kaur Sharnjeet

    2016-01-01

    Full Text Available Energy saving is difficult in wireless sensor network (WSN due to limited resources. Each node in WSN is constrained by their limited battery power for their energy. The energy is reduced as the time goes off due to the packet transmission and reception. Energy management techniques are necessary to minimize the total power consumption of all the nodes in the network in order to maximize its life span. Our proposed protocol Location based routing (LBR aimed to find a path which utilizes the minimum energy to transmit the packets between the source and the destination. The required energy for the transmission and reception of data is evaluated in MATLAB. LBR is implemented on Multicast Ad hoc On Demand Distance Vector Routing Protocol (MAODV to manage the energy consumption in the transmission and reception of data. Simulation results of LBR show the energy consumption has been reduced.

  20. Locating hardware faults in a data communications network of a parallel computer

    Science.gov (United States)

    Archer, Charles J.; Megerian, Mark G.; Ratterman, Joseph D.; Smith, Brian E.

    2010-01-12

    Hardware faults location in a data communications network of a parallel computer. Such a parallel computer includes a plurality of compute nodes and a data communications network that couples the compute nodes for data communications and organizes the compute node as a tree. Locating hardware faults includes identifying a next compute node as a parent node and a root of a parent test tree, identifying for each child compute node of the parent node a child test tree having the child compute node as root, running a same test suite on the parent test tree and each child test tree, and identifying the parent compute node as having a defective link connected from the parent compute node to a child compute node if the test suite fails on the parent test tree and succeeds on all the child test trees.

  1. Coverage improvement in clustered wireless sensor networks by relocating mobile nodes based on waypoints

    DEFF Research Database (Denmark)

    Mathur, Prateek; Nielsen, Rasmus Hjorth; Prasad, Neeli R.

    2013-01-01

    by clusters with relocation of mobile nodes between the clusters. Mobile nodes are guided by waypoints between source and destination clusters without use of localization services. The simulation results have been presented which state the effectiveness of the proposed approach. Mobile node relocation has...

  2. Influence of trap location on the efficiency of trapping in dendrimers and regular hyperbranched polymers.

    Science.gov (United States)

    Lin, Yuan; Zhang, Zhongzhi

    2013-03-07

    The trapping process in polymer systems constitutes a fundamental mechanism for various other dynamical processes taking place in these systems. In this paper, we study the trapping problem in two representative polymer networks, Cayley trees and Vicsek fractals, which separately model dendrimers and regular hyperbranched polymers. Our goal is to explore the impact of trap location on the efficiency of trapping in these two important polymer systems, with the efficiency being measured by the average trapping time (ATT) that is the average of source-to-trap mean first-passage time over every staring point in the whole networks. For Cayley trees, we derive an exact analytic formula for the ATT to an arbitrary trap node, based on which we further obtain the explicit expression of ATT for the case that the trap is uniformly distributed. For Vicsek fractals, we provide the closed-form solution for ATT to a peripheral node farthest from the central node, as well as the numerical solutions for the case when the trap is placed on other nodes. Moreover, we derive the exact formula for the ATT corresponding to the trapping problem when the trap has a uniform distribution over all nodes. Our results show that the influence of trap location on the trapping efficiency is completely different for the two polymer networks. In Cayley trees, the leading scaling of ATT increases with the shortest distance between the trap and the central node, implying that trap's position has an essential impact on the trapping efficiency; while in Vicsek fractals, the effect of location of the trap is negligible, since the dominant behavior of ATT is identical, respective of the location where the trap is placed. We also present that for all cases of trapping problems being studied, the trapping process is more efficient in Cayley trees than in Vicsek fractals. We demonstrate that all differences related to trapping in the two polymer systems are rooted in their underlying topological structures.

  3. Chemical shift effect predicting lymph node status in rectal cancer using high-resolution MR imaging with node-for-node matched histopathological validation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hongmei; Zhang, Chongda; Ye, Feng; Liu, Yuan; Zhou, Chunwu [Chinese Academy of Medical Sciences and Peking Union Medical College, Department of Diagnostic Radiology, National Cancer Center/Cancer Hospital, ChaoYang District, Beijing (China); Zheng, Zhaoxu [Chinese Academy of Medical Sciences and Peking Union Medical College, Department of Colorectal Oncology, National Cancer Center/Cancer Hospital, ChaoYang District, Beijing (China); Zou, Shuangmei [Chinese Academy of Medical Sciences and Peking Union Medical College, Department of Pathology, National Cancer Center/Cancer Hospital, ChaoYang District, Beijing (China)

    2017-09-15

    To evaluate the value of the chemical shift effect (CSE) as well as other criteria for the prediction of lymph node status. Twenty-nine patients who underwent radical surgery of rectal cancers were studied with pre- and postoperative specimen MRI. Lymph nodes were harvested from transverse whole-mount specimens and compared with in vivo and ex vivo images to obtain a precise slice-for-section match. Preoperative MR characteristics including CSE, as well as other predictors, were evaluated by two readers independently between benign and metastatic nodes. A total of 255 benign and 35 metastatic nodes were obtained; 71.4% and 69.4% of benign nodes were detected with regular CSE for two readers, whereas 80.0% and 74.3% of metastatic nodes with absence of CSE. The CSE rendered areas under the ROC curve (AUC) of 0.879 and 0.845 for predicting nodal status for two readers. The criteria of nodal location, border, signal intensity and minimum distance to the rectal wall were also useful but with AUCs (0.629-0.743) lower than those of CSE. CSE is a reliable predictor for differentiating benign from metastatic nodes. Additional criteria should be taken into account when it is difficult to determine the nodal status by using only a single predictor. (orig.)

  4. Edge- and Node-Disjoint Paths in P Systems

    Directory of Open Access Journals (Sweden)

    Michael J. Dinneen

    2010-10-01

    Full Text Available In this paper, we continue our development of algorithms used for topological network discovery. We present native P system versions of two fundamental problems in graph theory: finding the maximum number of edge- and node-disjoint paths between a source node and target node. We start from the standard depth-first-search maximum flow algorithms, but our approach is totally distributed, when initially no structural information is available and each P system cell has to even learn its immediate neighbors. For the node-disjoint version, our P system rules are designed to enforce node weight capacities (of one, in addition to edge capacities (of one, which are not readily available in the standard network flow algorithms.

  5. Assessing node risk and vulnerability in epidemics on networks

    Science.gov (United States)

    Rogers, T.

    2015-01-01

    Which nodes are most vulnerable to an epidemic spreading through a network, and which carry the highest risk of causing a major outbreak if they are the source of the infection? Here we show how these questions can be answered to good approximation using the cavity method. Several curious properties of node vulnerability and risk are explored: some nodes are more vulnerable than others to weaker infections, yet less vulnerable to stronger ones; a node is always more likely to be caught in an outbreak than it is to start one, except when the disease has a deterministic lifetime; the rank order of node risk depends on the details of the distribution of infectious periods.

  6. [Freehand SPECT for navigation and sentinel node detection in breast cancer].

    Science.gov (United States)

    Gillard, C; Franken, P; Darcourt, J; Barranger, E

    2015-02-01

    The sentinel lymph node (SLN) is a standard for the surgical treatment of axillary localized breast cancer N0. It is based on a double isotopic and color detection. With a gamma detecting probe connected to an infrared camera, Déclipse SPECT system (Surgiceye(®)) is able to detect and locate any radioactive source in 3D. Mobile character for use in the operating room is particularly interesting for the intraoperative detection of SLN. We illustrate its usefulness in a clinical case where the preoperative identification of SLN by lymphoscintigraphy was not informative. Copyright © 2014. Published by Elsevier SAS.

  7. Library Locations

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Carnegie Library of Pittsburgh locations including address, coordinates, phone number, square footage, and standard operating hours. The map below does not display...

  8. Location of Urban Logistic Terminals as Hub Location Problem

    Directory of Open Access Journals (Sweden)

    Jasmina Pašagić Škrinjar

    2012-09-01

    Full Text Available In this paper the problems of locating urban logistic terminals are studied as hub location problems that due to a large number of potential nodes in big cities belong to hard non-polynomial problems, the so-called NP-problems. The hub location problems have found wide application in physical planning of transport and telecommunication systems, especially systems of fast delivery, networks of logistic and distribution centres and cargo traffic terminals of the big cities, etc. The paper defines single and multiple allocations and studies the numerical examples. The capacitated single allocation hub location problems have been studied, with the provision of a mathematical model of selecting the location for the hubs on the network. The paper also presents the differences in the possibilities of implementing the exact and heuristic methods to solve the actual location problems of big dimensions i.e. hub problems of the big cities.

  9. The congestion control algorithm based on queue management of each node in mobile ad hoc networks

    Science.gov (United States)

    Wei, Yifei; Chang, Lin; Wang, Yali; Wang, Gaoping

    2016-12-01

    This paper proposes an active queue management mechanism, considering the node's own ability and its importance in the network to set the queue threshold. As the network load increases, local congestion of mobile ad hoc network may lead to network performance degradation, hot node's energy consumption increase even failure. If small energy nodes congested because of forwarding data packets, then when it is used as the source node will cause a lot of packet loss. This paper proposes an active queue management mechanism, considering the node's own ability and its importance in the network to set the queue threshold. Controlling nodes buffer queue in different levels of congestion area probability by adjusting the upper limits and lower limits, thus nodes can adjust responsibility of forwarding data packets according to their own situation. The proposed algorithm will slow down the send rate hop by hop along the data package transmission direction from congestion node to source node so that to prevent further congestion from the source node. The simulation results show that, the algorithm can better play the data forwarding ability of strong nodes, protect the weak nodes, can effectively alleviate the network congestion situation.

  10. A Grooming Nodes Optimal Allocation Method for Multicast in WDM Networks

    Directory of Open Access Journals (Sweden)

    Chengying Wei

    2016-01-01

    Full Text Available The grooming node has the capability of grooming multicast traffic with the small granularity into established light at high cost of complexity and node architecture. In the paper, a grooming nodes optimal allocation (GNOA method is proposed to optimize the allocation of the grooming nodes constraint by the blocking probability for multicast traffic in sparse WDM networks. In the proposed GNOA method, the location of each grooming node is determined by the SCLD strategy. The improved smallest cost largest degree (SCLD strategy is designed to select the nongrooming nodes in the proposed GNOA method. The simulation results show that the proposed GNOA method can reduce the required number of grooming nodes and decrease the cost of constructing a network to guarantee a certain request blocking probability when the wavelengths per fiber and transmitter/receiver ports per node are sufficient for the optical multicast in WDM networks.

  11. Gene Locater

    DEFF Research Database (Denmark)

    Anwar, Muhammad Zohaib; Sehar, Anoosha; Rehman, Inayat-Ur

    2012-01-01

    software's for calculating recombination frequency is mostly limited to the range and flexibility of this type of analysis. GENE LOCATER is a fully customizable program for calculating recombination frequency, written in JAVA. Through an easy-to-use interface, GENE LOCATOR allows users a high degree...... of flexibility in calculating genetic linkage and displaying linkage group. Among other features, this software enables user to identify linkage groups with output visualized graphically. The program calculates interference and coefficient of coincidence with elevated accuracy in sample datasets. AVAILABILITY...

  12. Novel Received Signal Strength-Based Indoor Location System: Development and Testing

    Directory of Open Access Journals (Sweden)

    Álvarez Yuri

    2010-01-01

    Full Text Available A received signal strength- (RSS-based indoor location method (ILS for person/assets location in indoor scenarios is presented in this paper. Theoretical bases of the method are the integral equations relating the electromagnetic (EM fields with their sources, establishing a cost function relating the measured field at the receivers and the unknown position of the transmitter. The aim is to improve the EM characterization of the scenario yielding in a more accurate indoor location method. Regarding network infrastructure implementation, a set of receivers are deployed through the coverage area, measuring the RSS value from a transmitter node which is attached to the asset to be located. The location method is evaluated in several indoor scenarios using portable measurement equipment. The next step has been the network hardware implementation using a wireless sensor network: for this purpose, ZigBee nodes have been selected. Finally, RSS measurements variability due to multipath effects and nonline-of-sight between transmitter and receiver nodes is mitigated using calibration and a correction based on the difference between the free space field decay law and the measured RSS.

  13. Final report for the mobile node authentication LDRD project.

    Energy Technology Data Exchange (ETDEWEB)

    Michalski, John T.; Lanzone, Andrew J.

    2005-09-01

    In hostile ad hoc wireless communication environments, such as battlefield networks, end-node authentication is critical. In a wired infrastructure, this authentication service is typically facilitated by a centrally-located ''authentication certificate generator'' such as a Certificate Authority (CA) server. This centralized approach is ill-suited to meet the needs of mobile ad hoc networks, such as those required by military systems, because of the unpredictable connectivity and dynamic routing. There is a need for a secure and robust approach to mobile node authentication. Current mechanisms either assign a pre-shared key (shared by all participating parties) or require that each node retain a collection of individual keys that are used to communicate with other individual nodes. Both of these approaches have scalability issues and allow a single compromised node to jeopardize the entire mobile node community. In this report, we propose replacing the centralized CA with a distributed CA whose responsibilities are shared between a set of select network nodes. To that end, we develop a protocol that relies on threshold cryptography to perform the fundamental CA duties in a distributed fashion. The protocol is meticulously defined and is implemented it in a series of detailed models. Using these models, mobile wireless scenarios were created on a communication simulator to test the protocol in an operational environment and to gather statistics on its scalability and performance.

  14. Hybrid tracers for sentinel node biopsy

    International Nuclear Information System (INIS)

    Van Den Berg, N. S.; Kleinjan, G. I.; Valdés-Olmos, R. A.; Buckle, T.; Van Leeuwen, F. I.; Klop, W. M.; Horenblas, S.; Van Der Poel, H. G.

    2014-01-01

    Conventional sentinel node (SN) mapping is performed by injection of a radiocolloid followed by lymphoscintigraphy to identify the number and location of the primary tumor draining lymph node(s), the so-called SN(s). Over the last decade research has focused on the introduction of new imaging agents that can further aid (surgical) SN identification. Different tracers for SN mapping, with varying sizes and isotopes have been reported, most of which have proven their value in a clinical setting. A major challenge lies in transferring this diagnostic information obtained at the nuclear medicine department to the operating theatre thereby providing the surgeon with (image) guidance. Conventionally, an intraoperative injection of vital blue dye or a fluorescence dye is given to allow intraoperative optical SN identification. However, for some indications, the radiotracer-based approach remains crucial. More recently, hybrid tracers, that contain both a radioactive and fluorescent label, were introduced to allow for direct integration of pre- and intraoperative guidance technologies. Their potential is especially high when they are used in combination with new surgical imaging modalities and navigation tools. Next to a description of the known tracers for SN mapping, this review discusses the application of hybrid tracers during SN biopsy and how the introduction of these new techniques can further aid in translation of nuclear medicine information into the operating theatre.

  15. Changes in abundance and nature of microimpact craters on the surfaces of Australasian microtektites with distance from the proposed source crater location

    Digital Repository Service at National Institute of Oceanography (India)

    ShyamPrasad, M.; Roy, S.K.; Gupta, A.

    of the craters are of erosive type (Fig. 2), i.e., those which contain a central pit which is surrounded by radial and concentric cracks, indicative of high velocity impacts (Hörz et al., 1971). This could be misleading, as observed in our earlier studies... of very small particles at high relative velocities. This location also has 9    the highest spatial density of impacts, i.e., it contains 230 micro-craters/cm 2 of the ocean floor (Table 2). AAS 22/8 (4052 km): Location : 07 0 05.289’S & 78 0...

  16. Constraining the source location of the 30 May 2015 (Mw 7.9) Bonin deep-focus earthquake using seismogram envelopes of high-frequency P waveforms: Occurrence of deep-focus earthquake at the bottom of a subducting slab

    Science.gov (United States)

    Takemura, Shunsuke; Maeda, Takuto; Furumura, Takashi; Obara, Kazushige

    2016-05-01

    In this study, the source location of the 30 May 2015 (Mw 7.9) deep-focus Bonin earthquake was constrained using P wave seismograms recorded across Japan. We focus on propagation characteristics of high-frequency P wave. Deep-focus intraslab earthquakes typically show spindle-shaped seismogram envelopes with peak delays of several seconds and subsequent long-duration coda waves; however, both the main shock and aftershock of the 2015 Bonin event exhibited pulse-like P wave propagations with high apparent velocities (~12.2 km/s). Such P wave propagation features were reproduced by finite-difference method simulations of seismic wave propagation in the case of slab-bottom source. The pulse-like P wave seismogram envelopes observed from the 2015 Bonin earthquake show that its source was located at the bottom of the Pacific slab at a depth of ~680 km, rather than within its middle or upper regions.

  17. Clinicopathologic risk factors for right paraesophageal lymph node metastasis in patients with papillary thyroid carcinoma.

    Science.gov (United States)

    Yu, Q A; Ma, D K; Liu, K P; Wang, P; Xie, C M; Wu, Y H; Dai, W J; Jiang, H C

    2018-03-17

    To investigate risk factors associated with right paraesophageal lymph node (RPELN) metastasis in patients with papillary thyroid carcinoma (PTC) and to determine the indications for right lymph node dissection. Clinicopathologic data from 829 patients (104 men and 725 women) with PTC, operated on by the same thyroid surgery team at the First Affiliated Hospital of Harbin Medical University from January 2013 to May 2017, were analyzed. Overall, 309 patients underwent total thyroidectomy with bilateral lymph node dissection, 488 underwent right thyroid lobe and isthmic resection with right central compartment lymph node dissection, and 32 underwent near-total thyroidectomy (ipsilateral thyroid lobectomy with contralateral near-total lobectomy) with bilateral lymph node dissection. The overall rate of central compartment lymph node metastasis was 43.5% (361/829), with right central compartment lymph node and RPELN metastasis rates of 35.5% (294/829) and 19.1% (158/829), respectively. Tumor size, number, invasion, and location, lymph node metastasis, right central compartment lymph node metastasis, and right lateral compartment lymph node metastasis were associated with RPELN in the univariate analysis, whereas age and sex were not. Multivariate analysis identified tumors with a diameter ≥ 1 cm, multiple tumors, tumors located in the right lobe, right central compartment lymph node metastasis, and right lateral compartment lymph node metastasis as independent risk factors for RPELN metastasis. Lymph node dissection, including RPELN dissection, should be performed for patients with PTC with a tumor diameter ≥ 1 cm, multiple tumors, right-lobe tumors, right central compartment lymph node metastasis, or suspected lateral compartment lymph node metastasis.

  18. Co-located monogenetic eruptions similar to 200 kyr apart driven by tapping vertically separated mantle source regions, Chagwido, Jeju Island, Republic of Korea

    NARCIS (Netherlands)

    Brenna, M.; Nemeth, K.; Cronin, S.J.; Sohn, Y.K.; Smith, I.E.M.; Wijbrans, J.R.

    2015-01-01

    New eruptions in monogenetic volcanic fields conceptually occur independently of previous ones. In some instances, however, younger volcanic structures and vents may overlap with older edifices. The genetic links between such co-located eruptions remain unclear. We mapped and analysed the

  19. Identification of acoustic wave propagation in a duct line and its application to detection of impact source location based on signal processing

    International Nuclear Information System (INIS)

    Shin, Yong Woo; Kim, Min Soo; Lee, Sang Kwon

    2010-01-01

    For the detection of the impact location in a pipeline system, the correlation method has been the conventional method. For the application of the correlation method, the diameter of a duct should be small so that the acoustic wave inside the duct can propagate with nondispersive characteristics, in the form of, for example, a plane wave. This correlation method calculates the cross-correlation between acoustic waves measured at two acceleration sensors attached to a buried duct. It also gives information about the arrival time delay of an acoustic wave between two sensors. These arrival time delays are used for the estimation of the impact location. However, when the diameter of the duct is large, the acoustic waves inside the duct propagate with dispersive characteristics owing to the reflection of the acoustic wave off of the wall of the duct. This dispersive characteristic is related to the acoustic modes inside a duct. Therefore, the correlation method does not work correctly for the detection of the impact location. This paper proposes new methods of accurately measuring the arrival time delay between two sensors attached to duct line system. This method is based on the time-frequency analyses of the short time Fourier transform (STFT) and continuous wavelet transform (CWT). These methods can discriminate direct waves (non-dispersive waves) and reflective waves (dispersive waves) from the measured wave signals through the time-frequency analysis. The direct wave or the reflective wave is used to estimate the arrival time delay. This delay is used for the identification of the impact location. This systematic method can predict the impact location due to the impact forces of construction equipment with more accuracy than the correlation method

  20. Ultrasound of the axilla: where to look for the sentinel lymph node

    International Nuclear Information System (INIS)

    Britton, P.; Moyle, P.; Benson, J.R.; Goud, A.; Sinnatamby, R.; Barter, S.; Gaskarth, M.; Provenzano, E.; Wallis, M.

    2010-01-01

    Aims: The aim of this paper is to guide the radiologist to the most likely location of the sentinel lymph node (SLN). Materials and methods: Patients with invasive breast cancer underwent axillary ultrasound examination. The position and morphological appearances of the lymph nodes were noted and core biopsy (CB) was performed of the largest or most suspicious node. Those patients whose biopsy revealed no evidence of malignancy proceeded to a surgical sentinel lymph node (SLN) biopsy (SLNB) looking for histopathological evidence of previous CB. Results: Of 121 patients who underwent axillary ultrasound and CB no malignancy was identified in 73, all of whom subsequently underwent SLNB. Histological evidence of CB in the SLN was identified in 47 (64%) patients. The position of all the lymph nodes identified on ultrasound and the 47 patients whose SLNs were identified were drawn on composite diagrams of the axilla. Of the 36 nodes identified as sentinel whose position relative to other nodes could be determined, 29 (81%) represented the lowest node identified in the axilla, four (11%) were the second lowest, and three (8%) were the third lowest node. None of the four patients whose CB was from the fourth lowest node had the CB site identified at subsequent SLNB. Conclusion: Ultrasound of the axilla should be carried out in a systematic fashion focusing on level I nodes paying particular attention to the lowest one or two lymph nodes.

  1. Ultrasound of the axilla: where to look for the sentinel lymph node

    Energy Technology Data Exchange (ETDEWEB)

    Britton, P., E-mail: peter.britton@addenbrookes.nhs.u [Cambridge Breast Unit, Addenbrooke' s Hospital, Cambridge (United Kingdom); Moyle, P.; Benson, J.R.; Goud, A.; Sinnatamby, R.; Barter, S.; Gaskarth, M.; Provenzano, E.; Wallis, M. [Cambridge Breast Unit, Addenbrooke' s Hospital, Cambridge (United Kingdom)

    2010-05-15

    Aims: The aim of this paper is to guide the radiologist to the most likely location of the sentinel lymph node (SLN). Materials and methods: Patients with invasive breast cancer underwent axillary ultrasound examination. The position and morphological appearances of the lymph nodes were noted and core biopsy (CB) was performed of the largest or most suspicious node. Those patients whose biopsy revealed no evidence of malignancy proceeded to a surgical sentinel lymph node (SLN) biopsy (SLNB) looking for histopathological evidence of previous CB. Results: Of 121 patients who underwent axillary ultrasound and CB no malignancy was identified in 73, all of whom subsequently underwent SLNB. Histological evidence of CB in the SLN was identified in 47 (64%) patients. The position of all the lymph nodes identified on ultrasound and the 47 patients whose SLNs were identified were drawn on composite diagrams of the axilla. Of the 36 nodes identified as sentinel whose position relative to other nodes could be determined, 29 (81%) represented the lowest node identified in the axilla, four (11%) were the second lowest, and three (8%) were the third lowest node. None of the four patients whose CB was from the fourth lowest node had the CB site identified at subsequent SLNB. Conclusion: Ultrasound of the axilla should be carried out in a systematic fashion focusing on level I nodes paying particular attention to the lowest one or two lymph nodes.

  2. Axillary node metastatic carcinoma without definitive primary: a case report

    Directory of Open Access Journals (Sweden)

    Spencer R. Anderson

    2016-01-01

    Full Text Available Cancer of unknown primary (CUP is the finding of a metastatic cancerous lesion without an established primary source localized within the body. CUP can be of any cancer cell type, however, adenocarcinoma is most often identified by histology. Up to 5% of all malignant diagnoses are classified as CUP. PET is an imaging modality often utilized to distinguish a primary source in the setting of CUP, yet often a primary is never identified. CUP can be further stratified using specific qualifiers as favorable and unfavorable, indicating the potential therapeutic response to treatment regimens. Treatment approach to CUP relies heavily on the cell type identified by histology, the location of the lesion, and the amount of spread within the body. In the typical setting and presentation, per current literature, CUP arises in the 7th decade of life in patients with multiple comorbidities, and often has a poor prognostic value. This case report identifies an atypical presentation of CUP, a 38-year-old Caucasian female with an axillary mobile mass, and no associated systemic symptoms. Biopsy of the node and immunohistochemical staining showed histology consistent with metastatic carcinoma. Mammography, MRI, and PET scan found no evidence of tumor primary or distant metastasis. Further staining confirmed metastatic carcinoma consistent with breast origin, without an established breast primary. As in this case, CUP may present in an atypical manner, warranting a thorough investigation aiming to identify the tumor primary to aid in identification of a proper treatment regimen and approach.

  3. Delineation of the geometry of the nodes in the Alps-Dinarides hinge zone and recognition of seismogenic nodes (M ≥ 6)

    International Nuclear Information System (INIS)

    Gorshkov, A.I.; Soloviev, A.A.; Panza, G.F.; Aoudia, A.; Peresan, A.

    2007-11-01

    In the junction zone between the Alps and the Dinarides, one of the most seismically active areas in Europe, we delineate a total of sixteen nodes which are capable of M ≥ 6.0 earthquakes using large-scale cartographic data. Seven of them have already experienced the occurrence of sufficiently well located earthquakes with M ≥ 6.0. Using these seven nodes as a learning set, we identify, by means of the pattern recognition methodology, three other nodes prone to earthquakes with M ≥ 6.0: one node in the Alpine domain and two in the northernmost Dinarides. (author)

  4. Development and evaluation of a decision-supporting model for identifying the source location of microbial intrusions in real gravity sewer systems.

    Science.gov (United States)

    Kim, Minyoung; Choi, Christopher Y; Gerba, Charles P

    2013-09-01

    Assuming a scenario of a hypothetical pathogenic outbreak, we aimed this study at developing a decision-support model for identifying the location of the pathogenic intrusion as a means of facilitating rapid detection and efficient containment. The developed model was applied to a real sewer system (the Campbell wash basin in Tucson, AZ) in order to validate its feasibility. The basin under investigation was divided into 14 sub-basins. The geometric information associated with the sewer network was digitized using GIS (Geological Information System) and imported into an urban sewer network simulation model to generate microbial breakthrough curves at the outlet. A pre-defined amount of Escherichia coli (E. coli), which is an indicator of fecal coliform bacteria, was hypothetically introduced into 56 manholes (four in each sub-basin, chosen at random), and a total of 56 breakthrough curves of E. coli were generated using the simulation model at the outlet. Transport patterns were classified depending upon the location of the injection site (manhole), various known characteristics (peak concentration and time, pipe length, travel time, etc.) extracted from each E. coli breakthrough curve and the layout of sewer network. Using this information, we back-predicted the injection location once an E. coli intrusion was detected at a monitoring site using Artificial Neural Networks (ANNs). The results showed that ANNs identified the location of the injection sites with 57% accuracy; ANNs correctly recognized eight out of fourteen expressions with relying on data from a single detection sensor. Increasing the available sensors within the basin significantly improved the accuracy of the simulation results (from 57% to 100%). Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Mastering Node.js

    CERN Document Server

    Pasquali, Sandro

    2013-01-01

    This book contains an extensive set of practical examples and an easy-to-follow approach to creating 3D objects.This book is great for anyone who already knows JavaScript and who wants to start creating 3D graphics that run in any browser. You don't need to know anything about advanced math or WebGL; all that is needed is a general knowledge of JavaScript and HTML. The required materials and examples can be freely downloaded and all tools used in this book are open source.

  6. Usefulness of CT-guided trans-bronchial needle aspiration biopsy for mediastinal lymph nodes

    International Nuclear Information System (INIS)

    Cui Bing; Rong Fu

    2001-01-01

    Objective: To determine the nature of enlarged mediastinal lymph nodes, the study of CT-guided trans-bronchial needle aspiration biopsy (CT-TBNA) was conducted. Methods: According to classification and locating standard of mediastinal lymph nodes, CT-TBNA was performed in 158 mediastinal lymph nodes of 73 patients, including 54 primary lung cancer with enlarged mediastinal lymph nodes, 5 malignant lymphoma, 3 mediastinal abscess and 11 mediastinal inflammatory adenopathy. Results: CT confirmed that the needles were inside all 158 lymph nodes. Adequate aspirates for histologic and/or cytologic diagnosis were obtained in 136 of 158(86%) lymph node biopsies. No serious complications occurred. Conclusion: Locating standard of CT-guided TBNA was reliable. Puncture was safe and cost-effective. CT-TBNA was important for ascertaining the nature of mediastinal adenopathy and staging of neoplasms

  7. Centroid Localization of Uncooperative Nodes in Wireless Networks Using a Relative Span Weighting Method

    Directory of Open Access Journals (Sweden)

    Christine Laurendeau

    2010-01-01

    Full Text Available Increasingly ubiquitous wireless technologies require novel localization techniques to pinpoint the position of an uncooperative node, whether the target is a malicious device engaging in a security exploit or a low-battery handset in the middle of a critical emergency. Such scenarios necessitate that a radio signal source be localized by other network nodes efficiently, using minimal information. We propose two new algorithms for estimating the position of an uncooperative transmitter, based on the received signal strength (RSS of a single target message at a set of receivers whose coordinates are known. As an extension to the concept of centroid localization, our mechanisms weigh each receiver's coordinates based on the message's relative RSS at that receiver, with respect to the span of RSS values over all receivers. The weights may decrease from the highest RSS receiver either linearly or exponentially. Our simulation results demonstrate that for all but the most sparsely populated wireless networks, our exponentially weighted mechanism localizes a target node within the regulations stipulated for emergency services location accuracy.

  8. ACTRIS ACSM intercomparison - Part 2: Intercomparison of ME-2 organic source apportionment results from 15 individual, co-located aerosol mass spectrometers

    Science.gov (United States)

    Fröhlich, R.; Crenn, V.; Setyan, A.; Belis, C. A.; Canonaco, F.; Favez, O.; Riffault, V.; Slowik, J. G.; Aas, W.; Aijälä, M.; Alastuey, A.; Artiñano, B.; Bonnaire, N.; Bozzetti, C.; Bressi, M.; Carbone, C.; Coz, E.; Croteau, P. L.; Cubison, M. J.; Esser-Gietl, J. K.; Green, D. C.; Gros, V.; Heikkinen, L.; Herrmann, H.; Jayne, J. T.; Lunder, C. R.; Minguillón, M. C.; Močnik, G.; O'Dowd, C. D.; Ovadnevaite, J.; Petralia, E.; Poulain, L.; Priestman, M.; Ripoll, A.; Sarda-Estève, R.; Wiedensohler, A.; Baltensperger, U.; Sciare, J.; Prévôt, A. S. H.

    2015-06-01

    Chemically resolved atmospheric aerosol data sets from the largest intercomparison of the Aerodyne aerosol chemical speciation monitors (ACSMs) performed to date were collected at the French atmospheric supersite SIRTA. In total 13 quadrupole ACSMs (Q-ACSM) from the European ACTRIS ACSM network, one time-of-flight ACSM (ToF-ACSM), and one high-resolution ToF aerosol mass spectrometer (AMS) were operated in parallel for about 3 weeks in November and December~2013. Part 1 of this study reports on the accuracy and precision of the instruments for all the measured species. In this work we report on the intercomparison of organic components and the results from factor analysis source apportionment by positive matrix factorisation (PMF) utilising the multilinear engine 2 (ME-2). Except for the organic contribution of mass-to-charge ratio m/z 44 to the total organics (f44), which varied by factors between 0.6 and 1.3 compared to the mean, the peaks in the organic mass spectra were similar among instruments. The m/z 44 differences in the spectra resulted in a variable f44 in the source profiles extracted by ME-2, but had only a minor influence on the extracted mass contributions of the sources. The presented source apportionment yielded four factors for all 15 instruments: hydrocarbon-like organic aerosol (HOA), cooking-related organic aerosol (COA), biomass burning-related organic aerosol (BBOA) and secondary oxygenated organic aerosol (OOA). ME-2 boundary conditions (profile constraints) were optimised individually by means of correlation to external data in order to achieve equivalent / comparable solutions for all ACSM instruments and the results are discussed together with the investigation of the influence of alternative anchors (reference profiles). A comparison of the ME-2 source apportionment output of all 15 instruments resulted in relative standard deviations (SD) from the mean between 13.7 and 22.7 % of the source's average mass contribution depending on the

  9. ACTRIS ACSM intercomparison – Part 2: Intercomparison of ME-2 organic source apportionment results from 15 individual, co-located aerosol mass spectrometers

    Directory of Open Access Journals (Sweden)

    R. Fröhlich

    2015-06-01

    Full Text Available Chemically resolved atmospheric aerosol data sets from the largest intercomparison of the Aerodyne aerosol chemical speciation monitors (ACSMs performed to date were collected at the French atmospheric supersite SIRTA. In total 13 quadrupole ACSMs (Q-ACSM from the European ACTRIS ACSM network, one time-of-flight ACSM (ToF-ACSM, and one high-resolution ToF aerosol mass spectrometer (AMS were operated in parallel for about 3 weeks in November and December~2013. Part 1 of this study reports on the accuracy and precision of the instruments for all the measured species. In this work we report on the intercomparison of organic components and the results from factor analysis source apportionment by positive matrix factorisation (PMF utilising the multilinear engine 2 (ME-2. Except for the organic contribution of mass-to-charge ratio m/z 44 to the total organics (f44, which varied by factors between 0.6 and 1.3 compared to the mean, the peaks in the organic mass spectra were similar among instruments. The m/z 44 differences in the spectra resulted in a variable f44 in the source profiles extracted by ME-2, but had only a minor influence on the extracted mass contributions of the sources. The presented source apportionment yielded four factors for all 15 instruments: hydrocarbon-like organic aerosol (HOA, cooking-related organic aerosol (COA, biomass burning-related organic aerosol (BBOA and secondary oxygenated organic aerosol (OOA. ME-2 boundary conditions (profile constraints were optimised individually by means of correlation to external data in order to achieve equivalent / comparable solutions for all ACSM instruments and the results are discussed together with the investigation of the influence of alternative anchors (reference profiles. A comparison of the ME-2 source apportionment output of all 15 instruments resulted in relative standard deviations (SD from the mean between 13.7 and 22.7 % of the source's average mass contribution depending on

  10. Deployment of check-in nodes in complex networks

    Science.gov (United States)

    Jiang, Zhong-Yuan; Ma, Jian-Feng

    2017-01-01

    In many real complex networks such as the city road networks and highway networks, vehicles often have to pass through some specially functioned nodes to receive check-in like services such as gas supplement at gas stations. Based on existing network structures, to guarantee every shortest path including at least a check-in node, the location selection of all check-in nodes is very essential and important to make vehicles to easily visit these check-in nodes, and it is still remains an open problem in complex network studies. In this work, we aim to find possible solutions for this problem. We first convert it into a set cover problem which is NP-complete and propose to employ the greedy algorithm to achieve an approximate result. Inspired by heuristic information of network structure, we discuss other four check-in node location deployment methods including high betweenness first (HBF), high degree first (HDF), random and low degree first (LDF). Finally, we compose extensive simulations in classical scale-free networks, random networks and real network models, and the results can well confirm the effectiveness of the greedy algorithm. This work has potential applications into many real networks.

  11. Lymph node metastasis in the biliary tract carcinoma: CT evaluation

    International Nuclear Information System (INIS)

    Lee, Byung Hee; Lee, Ah Ra; Kim, Kie Hwan; Do, Young Soo; Chin, Soo Yil

    1994-01-01

    The primary biliary carcinoma is usually unresectable at presentation, because of early lymphatic spread. To determine the incidence and the spread pattern of lymph node metastases according to the location of the primary tumor, we analyzed the CT scans of the patients with primary biliary adenocarcinoma. We reviewed the CT scans of 92 patients with pathologically proven primary biliary adenocacinima, including 45 peripheral cholangiocarcinomas, 22 hilar cholangiocarcinomas, 18 gallbladder carcinomas, and 7 common bile duct carcinomas. Positive adenopathy was diagnosed when the node exceeded 10 mm in short axis. The overall incidence of nodal metastases was 59.8% (55/92); 66.7% in peripheral cholangiocarcinoma, 54.5% in hilar cholangiocarcinoma, 55.6% in gallbladder carcinoma, and 42.9% in common bile duct carcinoma. The most commonly involved nodal group was the lesser omentum, followed by the celiac, periaortic, and peripancreatic group. The phrenic node group was only involved in the cases with the peripheral or hilar cholangiocarcinoma. The primary biliary carcinoma has a high incidence of lymph node metastases at the time of diagnosis, and shows different nodal spread pattern according to the location of the primary tumor. Involvement of the phrenic node was limited to the peripheral and hilar cholangiocarcinoma

  12. Lymph node metastasis in the biliary tract carcinoma: CT evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byung Hee; Lee, Ah Ra; Kim, Kie Hwan; Do, Young Soo; Chin, Soo Yil [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    1994-07-15

    The primary biliary carcinoma is usually unresectable at presentation, because of early lymphatic spread. To determine the incidence and the spread pattern of lymph node metastases according to the location of the primary tumor, we analyzed the CT scans of the patients with primary biliary adenocarcinoma. We reviewed the CT scans of 92 patients with pathologically proven primary biliary adenocacinima, including 45 peripheral cholangiocarcinomas, 22 hilar cholangiocarcinomas, 18 gallbladder carcinomas, and 7 common bile duct carcinomas. Positive adenopathy was diagnosed when the node exceeded 10 mm in short axis. The overall incidence of nodal metastases was 59.8% (55/92); 66.7% in peripheral cholangiocarcinoma, 54.5% in hilar cholangiocarcinoma, 55.6% in gallbladder carcinoma, and 42.9% in common bile duct carcinoma. The most commonly involved nodal group was the lesser omentum, followed by the celiac, periaortic, and peripancreatic group. The phrenic node group was only involved in the cases with the peripheral or hilar cholangiocarcinoma. The primary biliary carcinoma has a high incidence of lymph node metastases at the time of diagnosis, and shows different nodal spread pattern according to the location of the primary tumor. Involvement of the phrenic node was limited to the peripheral and hilar cholangiocarcinoma.

  13. Locating hardware faults in a parallel computer

    Science.gov (United States)

    Archer, Charles J.; Megerian, Mark G.; Ratterman, Joseph D.; Smith, Brian E.

    2010-04-13

    Locating hardware faults in a parallel computer, including defining within a tree network of the parallel computer two or more sets of non-overlapping test levels of compute nodes of the network that together include all the data communications links of the network, each non-overlapping test level comprising two or more adjacent tiers of the tree; defining test cells within each non-overlapping test level, each test cell comprising a subtree of the tree including a subtree root compute node and all descendant compute nodes of the subtree root compute node within a non-overlapping test level; performing, separately on each set of non-overlapping test levels, an uplink test on all test cells in a set of non-overlapping test levels; and performing, separately from the uplink tests and separately on each set of non-overlapping test levels, a downlink test on all test cells in a set of non-overlapping test levels.

  14. Multi-Source Cooperative Data Collection with a Mobile Sink for the Wireless Sensor Network.

    Science.gov (United States)

    Han, Changcai; Yang, Jinsheng

    2017-10-30

    The multi-source cooperation integrating distributed low-density parity-check codes is investigated to jointly collect data from multiple sensor nodes to the mobile sink in the wireless sensor network. The one-round and two-round cooperative data collection schemes are proposed according to the moving trajectories of the sink node. Specifically, two sparse cooperation models are firstly formed based on geographical locations of sensor source nodes, the impairment of inter-node wireless channels and moving trajectories of the mobile sink. Then, distributed low-density parity-check codes are devised to match the directed graphs and cooperation matrices related with the cooperation models. In the proposed schemes, each source node has quite low complexity attributed to the sparse cooperation and the distributed processing. Simulation results reveal that the proposed cooperative data collection schemes obtain significant bit error rate performance and the two-round cooperation exhibits better performance compared with the one-round scheme. The performance can be further improved when more source nodes participate in the sparse cooperation. For the two-round data collection schemes, the performance is evaluated for the wireless sensor networks with different moving trajectories and the variant data sizes.

  15. Intraoperative Sentinel Lymph Node Evaluation

    DEFF Research Database (Denmark)

    Shaw, Richard; Christensen, Anders; Java, Kapil

    2016-01-01

    BACKGROUND: Intraoperative analysis of sentinel lymph nodes would enhance the care of early-stage oral squamous cell carcinoma (OSCC). We determined the frequency and extent of cytokeratin 19 (CK19) expression in OSCC primary tumours and surrounding tissues to explore the feasibility of a "clinic......-ready" intraoperative diagnostic test (one step nucleic acid amplification-OSNA, sysmex). METHODS: Two cohorts were assembled: cohort 1, OSCC with stage and site that closely match cases suitable for sentinel lymph node biopsy (SLNB); cohort 2, HNSCC with sufficient fresh tumour tissue available for the OSNA assay (>50......% of tumours. Discordance between different techniques indicated that OSNA was more sensitive than qRT-PCR or RNA-ISH, which in turn were more sensitive than IHC. OSNA results showed CK19 expression in 80% of primary cases, so if used for diagnosis of lymph node metastasis would lead to a false-negative result...

  16. Methodology of sentinel node detection

    International Nuclear Information System (INIS)

    Maublant, J.

    2000-01-01

    The isotopic localisation of the sentinel node, i.e., the first functional lymph node in a tumor basin, is probably the fastest growing field ever experienced in nuclear medicine. Although based on the simple concept of the lymphatic migration of Tc-labeled colloids, the choice of the optimal technique remains controversial. We review and discuss the role of the colloids, of the site of injection, of the injected volume, of early imaging and of the colorimetric approach. Initially applied to melanoma and breast cancer, the sentinel node detection is now tested in other types of cancer such as lung, colon and prostate. It could become one of the leading tools in minimally invasive surgical oncology. The nuclear medicine physician has to remain aware of the rapid evolutions in this field in order to be able to answer to a rapidly growing demand. (author)

  17. Sediment Sources Change for the Past 42 Years in a Small Watershed Located in the Black Soil Region of Northeastern China Based on Fingerprinting Method

    Science.gov (United States)

    Du, P.; Huang, D.; Ning, D.

    2017-12-01

    The temporal change of sediment source in watershed is very helpful for evaluating the adopted soil conservation measures and the implemented land management practices. For this purpose, a sediment profile from Hebei watershed outlet and 59 samples from the three potential sediment sources were collected. The rediounuclide Pb-210 was then measured to obtain sedimentation rate for the past 42 years. Generally, the sedimentation rate was gradually decreased from 10.83 cm yr-1 in the 1970's to 1.50 cm yr-1in the 2010's. Taken the radiounulide Cs-137 as a fingerprinting identifying tracer, the mean contribution of sediment from cultivated lands, woodlands, and channel banks were 50.60%, 22.26%, and 26.74%, while the ranges varying from 20.16% to 84.02%, from 2.22% to 36.85%, and from 11.61% to 53.28%, respectively. The percentage of sediment sources from cultivated lands was decreased, whereas the percentages from woodlands and channel banks were both increased in the past 42 years. The results indicate that soil conservation measures adopted in the cultivated lands have been played a very important role in reducing erosion, however, more attention on land management practices implementation should be paid to maintain current woodland and to control serious gully erosion in the black soil region. (This paper is a contribution to the project of National Natural Science Foundation of China (No. 41501299), and the non-profit project of Ministry of Water Resources of China (No. 201501045).)

  18. Gray-scale contrast-enhanced utrasonography in detecting sentinel lymph nodes: An animal study

    International Nuclear Information System (INIS)

    Wang Yuexiang; Cheng Zhigang; Li Junlai; Tang Jie

    2010-01-01

    Objective: To investigate the usefulness of gray-scale contrast-enhanced ultrasonography for detecting sentinel lymph nodes. Methods: Contrast-enhanced ultrasonography was performed in five normal dogs (four female and one male) after subcutaneous administration of a sonographic contrast agent (Sonovue, Bracco, Milan, Italy). Four distinct regions in each animal were examined. After contrast-enhanced ultrasonography, 0.8 ml of blue dye was injected into the same location as Sonovue and the sentinel lymph nodes were detected by surgical dissection. The findings of contrast-enhanced ultrasonography were compared with those of the blue dye. Results: Twenty-one sentinel lymph nodes were detected by contrast-enhanced ultrasonography while 23 were identified by blue dye with surgical dissection. Compared with the blue dye, the detection rate of enhanced ultrasonography for the sentinel lymph nodes is 91.3% (21/23). Two patterns of enhancement in the sentinel lymph nodes were observed: complete enhancement (5 sentinel lymph nodes) and partial enhancement (16 sentinel lymph nodes). The lymphatic channels were demonstrated as hyperechoic linear structures leading from the injection site and could be readily followed to their sentinel lymph nodes. Histopathologic examination showed proliferation of lymphatic follicles or lymphatic sinus in partial enhanced sentinel lymph nodes while normal lymphatic tissue was demonstrated in completely enhanced sentinel lymph nodes. Conclusions: Sonovue combined with gray-scale contrast-enhanced ultrasonography may provide a feasible method for detecting sentinel lymph nodes.

  19. CHEMICAL PROFILES OF HONEYS ORIGINATING FROM DIFFERENT FLORAL SOURCES AND GEOGRAPHIC LOCATIONS EXAMINED BY A COMBINATION OF THREE EXTRACTION AND ANALYSIS TECHNIQUES

    Directory of Open Access Journals (Sweden)

    D. M. Meloncelli

    2015-05-01

    Full Text Available The chemical profiles of Tasmanian Leatherwood and Manuka honeys from Tasmania and New Zealand have been compared by a combination of GC-MS analysis of volatiles and semi-volatiles, RP-HPLC-DAD analysis of phenolics and flavonoids and HPLC-DAD analysis of derivatised dihydroxyacetone, hydroxymethylfurfural and methylglyoxal. This study found that Tasmanian and New Zealand Manuka honeys have high concentrations of methylglyoxal. However, syringic acid was only detected in Manuka honeys grown in New Zealand. The Tasmanian honeys can be distinguished by the higher concentration of 3-phenyllactic acid in Manuka compared to Leatherwood floral sources.

  20. CHEMICAL PROFILES OF HONEYS ORIGINATING FROM DIFFERENT FLORAL SOURCES AND GEOGRAPHIC LOCATIONS EXAMINED BY A COMBINATION OF THREE EXTRACTION AND ANALYSIS TECHNIQUES

    Directory of Open Access Journals (Sweden)

    D. M. Meloncelli,

    2015-02-01

    Full Text Available The chemical profiles of Tasmanian Leatherwood and Manuka honeys from Tasmania and New Zealand have been compared by a combination of GC-MS analysis of volatiles and semi-volatiles, RP-HPLC-DAD analysis of phenolics and flavonoids and HPLC-DAD analysis of derivatised dihydroxyacetone, hydroxymethylfurfural and methylglyoxal. This study found that Tasmanian and New Zealand Manuka honeys have high concentrations of methylglyoxal. However, syringic acid was only detected in Manuka honeys grown in New Zealand. The Tasmanian honeys can be distinguished by the higher concentration of 3-phenyllactic acid in Manuka compared to Leatherwood floral sources.

  1. The Icelandic volcanological data node and data service

    Science.gov (United States)

    Vogfjord, Kristin; Sigmundsson, Freysteinn; Futurevolc Team

    2013-04-01

    Through funding from the European FP7 programme, the International Civil Aviation Authority (ICAO), as well as the local Icelandic government and RANNÍS research fund, the establishment of the Icelandic volcano observatory (VO) as a cross-disciplinary, international volcanological data node and data service is starting to materialize. At the core of this entity is the close collaboration between the Icelandic Meteorological Office (IMO), a natural hazard monitoring and research institution, and researchers at the Earth Science Institute of the University of Iceland, ensuring long-term sustainable access to research quality data and products. Existing Icelandic Earth science monitoring and research infrastructures are being prepared for integration with the European EPOS infrastructure. Because the VO is located at a Met Office, this infrastructure also includes meteorological infrastructures relevant to volcanology. Furthermore, the FP7 supersite project, FUTUREVOLC cuts across disciplines to bring together European researchers from Earth science, atmospheric science, remote sensing and space science focussed on combined processing of the different data sources and results to generate a multiparametric volcano monitoring and early warning system. Integration with atmospheric and space science is to meet the need for better estimates of the volcanic eruption source term and dispersion, which depend not only on the magma flow rate and composition, but also on atmosphere-plume interaction and dispersion. This should lead to better estimates of distribution of ash in the atmosphere. FUTUREVOLC will significantly expand the existing Icelandic EPOS infrastructure to an even more multidisciplinary volcanological infrastructure. A central and sustainable part of the project is the establishment of a research-quality data centre at the VO. This data centre will be able to serve as a volcanological data node within EPOS, making multidisciplinary data accessible to

  2. The location of uranium in source rocks and sites of secondary deposition at the Needle's Eye natural analogue site, Dumfries and Galloway

    International Nuclear Information System (INIS)

    Basham, I.R.; Hyslop, E.K.; Milodowski, A.E.; Pearce, J.M.

    1989-08-01

    The British Geological Survey has been conducting a co-ordinated research programme at the natural analogue site of Needle's Eye at Southwick on the Solway coast in SW Scotland. This study of a naturally radioactive geochemical system has been carried out with the aim of improving our confidence in using predictive models of radionuclide migration in the geosphere. This report describes results of integrated mineralogical techniques which have been applied to the study of both the 'source-term' and sites of secondary accumulation of uranium. Pitchblende in a polymetallic-carbonate breccia vein exposed in ancient sea-cliffs is the main source of labile uranium although other uranium-bearing minerals present in the granodiorite and hornfelsed siltstone host-rocks present probable ancillary leachable sites. In keeping with the complex chemistry of the primary sulphide-rich mineralization, a large variety of secondary U minerals has been recorded among which arsenates and hydrous silicates appear to predominate. Uranium transported in groundwaters draining the cliffs has accumulated in organic-rich estuarine/intertidal mudflat sediments of Quaternary age. Charged particle track registration techniques have demonstrated convincingly the effectiveness of humidified organic matter in retarding uranium transport and, coupled with scanning electron microscopy, have indicated an important role of living plants and bacteria in uranium uptake and concentration. (author)

  3. The location of uranium in source rocks and sites of secondary deposition at the Needle's Eye natural analogue site, Dumfries and Galloway

    International Nuclear Information System (INIS)

    Basham, I.R.; Hyslop, E.K.; Milodowski, A.E.; Pearce, J.M.

    1991-01-01

    The British Geological Survey has been conducting a coordinated research programme at the natural analogue site of Needle's Eye at Southwick on the Solway coast in south-west Scotland. This study of a naturally radioactive geochemical system has been carried out with the aim of improving our confidence in using predictive models of radionuclide migration in the geosphere. This report describes results of integrated mineralogical techniques which have been applied to the study of both the source-term and sites of secondary accumulation of uranium. Pitchblende in a polymetallic-carbonate breccia vein exposed in ancient sea-cliffs is the main source of labile uranium although other uranium-bearing minerals present in the granodiorite and hornfelsed siltstone host-rocks present probable ancillary leachable sites. In keeping with the complex chemistry of the primary sulphide-rich mineralization, a large variety of secondary U minerals has been recorded among which arsenates and hydrous silicates appear to predominate. Uranium transported in groundwaters draining the cliffs has accumulated in organic-rich estuarine/intertidal mudflat sediments of Quaternary age. Charged particle track registration techniques have demonstrated convincingly the effectiveness of humified organic matter in retarding uranium transport and, coupled with scanning electron microscopy, have indicated the important role of living plants and bacteria in uranium uptake and concentration. Computer codes used: CHEMVAL; CHEMTARD 5 figs.; 64 plates; 37 refs

  4. Mediastinal lymph node detection and station mapping on chest CT using spatial priors and random forest

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jiamin; Hoffman, Joanne; Zhao, Jocelyn; Yao, Jianhua; Lu, Le; Kim, Lauren; Turkbey, Evrim B.; Summers, Ronald M., E-mail: rms@nih.gov [Imaging Biomarkers and Computer-aided Diagnosis Laboratory, Radiology and Imaging Sciences, National Institutes of Health Clinical Center Building, 10 Room 1C224 MSC 1182, Bethesda, Maryland 20892-1182 (United States)

    2016-07-15

    Purpose: To develop an automated system for mediastinal lymph node detection and station mapping for chest CT. Methods: The contextual organs, trachea, lungs, and spine are first automatically identified to locate the region of interest (ROI) (mediastinum). The authors employ shape features derived from Hessian analysis, local object scale, and circular transformation that are computed per voxel in the ROI. Eight more anatomical structures are simultaneously segmented by multiatlas label fusion. Spatial priors are defined as the relative multidimensional distance vectors corresponding to each structure. Intensity, shape, and spatial prior features are integrated and parsed by a random forest classifier for lymph node detection. The detected candidates are then segmented by the following curve evolution process. Texture features are computed on the segmented lymph nodes and a support vector machine committee is used for final classification. For lymph node station labeling, based on the segmentation results of the above anatomical structures, the textual definitions of mediastinal lymph node map according to the International Association for the Study of Lung Cancer are converted into patient-specific color-coded CT image, where the lymph node station can be automatically assigned for each detected node. Results: The chest CT volumes from 70 patients with 316 enlarged mediastinal lymph nodes are used for validation. For lymph node detection, their system achieves 88% sensitivity at eight false positives per patient. For lymph node station labeling, 84.5% of lymph nodes are correctly assigned to their stations. Conclusions: Multiple-channel shape, intensity, and spatial prior features aggregated by a random forest classifier improve mediastinal lymph node detection on chest CT. Using the location information of segmented anatomic structures from the multiatlas formulation enables accurate identification of lymph node stations.

  5. Mediastinal lymph node detection and station mapping on chest CT using spatial priors and random forest

    International Nuclear Information System (INIS)

    Liu, Jiamin; Hoffman, Joanne; Zhao, Jocelyn; Yao, Jianhua; Lu, Le; Kim, Lauren; Turkbey, Evrim B.; Summers, Ronald M.

    2016-01-01

    Purpose: To develop an automated system for mediastinal lymph node detection and station mapping for chest CT. Methods: The contextual organs, trachea, lungs, and spine are first automatically identified to locate the region of interest (ROI) (mediastinum). The authors employ shape features derived from Hessian analysis, local object scale, and circular transformation that are computed per voxel in the ROI. Eight more anatomical structures are simultaneously segmented by multiatlas label fusion. Spatial priors are defined as the relative multidimensional distance vectors corresponding to each structure. Intensity, shape, and spatial prior features are integrated and parsed by a random forest classifier for lymph node detection. The detected candidates are then segmented by the following curve evolution process. Texture features are computed on the segmented lymph nodes and a support vector machine committee is used for final classification. For lymph node station labeling, based on the segmentation results of the above anatomical structures, the textual definitions of mediastinal lymph node map according to the International Association for the Study of Lung Cancer are converted into patient-specific color-coded CT image, where the lymph node station can be automatically assigned for each detected node. Results: The chest CT volumes from 70 patients with 316 enlarged mediastinal lymph nodes are used for validation. For lymph node detection, their system achieves 88% sensitivity at eight false positives per patient. For lymph node station labeling, 84.5% of lymph nodes are correctly assigned to their stations. Conclusions: Multiple-channel shape, intensity, and spatial prior features aggregated by a random forest classifier improve mediastinal lymph node detection on chest CT. Using the location information of segmented anatomic structures from the multiatlas formulation enables accurate identification of lymph node stations.

  6. Location aware event driven multipath routing in Wireless Sensor Networks: Agent based approach

    Directory of Open Access Journals (Sweden)

    A.V. Sutagundar

    2013-03-01

    Full Text Available Wireless Sensor Networks (WSNs demand reliable and energy efficient paths for critical information delivery to sink node from an event occurrence node. Multipath routing facilitates reliable data delivery in case of critical information. This paper proposes an event triggered multipath routing in WSNs by employing a set of static and mobile agents. Every sensor node is assumed to know the location information of the sink node and itself. The proposed scheme works as follows: (1 Event node computes the arbitrary midpoint between an event node and the sink node by using location information. (2 Event node establishes a shortest path from itself to the sink node through the reference axis by using a mobile agent with the help of location information; the mobile agent collects the connectivity information and other parameters of all the nodes on the way and provides the information to the sink node. (3 Event node finds the arbitrary location of the special (middle intermediate nodes (above/below reference axis by using the midpoint location information given in step 1. (4 Mobile agent clones from the event node and the clones carry the event type and discover the path passing through special intermediate nodes; the path above/below reference axis looks like an arc. While migrating from one sensor node to another along the traversed path, each mobile agent gathers the node information (such as node id, location information, residual energy, available bandwidth, and neighbors connectivity and delivers to the sink node. (5 The sink node constructs a partial topology, connecting event and sink node by using the connectivity information delivered by the mobile agents. Using the partial topology information, sink node finds the multipath and path weight factor by using link efficiency, energy ratio, and hop distance. (6 The sink node selects the number of paths among the available paths based upon the criticalness of an event, and (7 if the event is non

  7. Allocating resources between network nodes for providing a network node function

    NARCIS (Netherlands)

    Strijkers, R.J.; Meulenhoff, P.J.

    2014-01-01

    The invention provides a method wherein a first network node advertises available resources that a second network node may use to offload network node functions transparently to the first network node. Examples of the first network node are a client device (e.g. PC, notebook, tablet, smart phone), a

  8. Applying the flow-capturing location-allocation model to an authentic network: Edmonton, Canada

    NARCIS (Netherlands)

    M.J. Hodgson (John); K.E. Rosing (Kenneth); A.L.G. Storrier (Leontien)

    1996-01-01

    textabstractTraditional location-allocation models aim to locate network facilities to optimally serve demand expressed as weights at nodes. For some types of facilities demand is not expressed at nodes, but as passing network traffic. The flow-capturing location-allocation model responds to this

  9. Does the atrioventricular node conduct?

    NARCIS (Netherlands)

    Meijler, F.L.; Fisch, C.

    1989-01-01

    It is difficult to be certain wh en the term "conduction" was first applied to the transfer of atrial activation to the ventricles .' In 1894, Engelmann used the word "Leitung", which can be translated as "connection" or as "conduction" .2 In 1906, Tawara described the atrioventricular node,

  10. Node.js by example

    CERN Document Server

    Tsonev, Krasimir

    2015-01-01

    If you are a JavaScript developer with no experience with Node.js or server-side web development, this book is for you. It will lead you through creating a fairly complex social network. You will learn how to work with a database and create real-time communication channels.

  11. Critical nodes in signalling pathways

    DEFF Research Database (Denmark)

    Taniguchi, Cullen M; Emanuelli, Brice; Kahn, C Ronald

    2006-01-01

    Physiologically important cell-signalling networks are complex, and contain several points of regulation, signal divergence and crosstalk with other signalling cascades. Here, we use the concept of 'critical nodes' to define the important junctions in these pathways and illustrate their unique role...... using insulin signalling as a model system....

  12. Time of arrival based location estimation for cooperative relay networks

    KAUST Repository

    Çelebi, Hasari Burak

    2010-09-01

    In this paper, we investigate the performance of a cooperative relay network performing location estimation through time of arrival (TOA). We derive Cramer-Rao lower bound (CRLB) for the location estimates using the relay network. The analysis is extended to obtain average CRLB considering the signal fluctuations in both relay and direct links. The effects of the channel fading of both relay and direct links and amplification factor and location of the relay node on average CRLB are investigated. Simulation results show that the channel fading of both relay and direct links and amplification factor and location of relay node affect the accuracy of TOA based location estimation. ©2010 IEEE.

  13. Time of arrival based location estimation for cooperative relay networks

    KAUST Repository

    Ç elebi, Hasari Burak; Abdallah, Mohamed M.; Hussain, Syed Imtiaz; Qaraqe, Khalid A.; Alouini, Mohamed-Slim

    2010-01-01

    In this paper, we investigate the performance of a cooperative relay network performing location estimation through time of arrival (TOA). We derive Cramer-Rao lower bound (CRLB) for the location estimates using the relay network. The analysis is extended to obtain average CRLB considering the signal fluctuations in both relay and direct links. The effects of the channel fading of both relay and direct links and amplification factor and location of the relay node on average CRLB are investigated. Simulation results show that the channel fading of both relay and direct links and amplification factor and location of relay node affect the accuracy of TOA based location estimation. ©2010 IEEE.

  14. Computed tomographic feature of regional lymph nodes involvement in primary hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Kim, Ki Whang; Kim, Hyung Sik; Lee, Jong Tae; Chung, Tae Sub; Sub, Jung Ho; Auh, Yong Ho

    1987-01-01

    The resectability of hepatocellular carcinoma is determined by the extent of hepatic involvement, the presence or absence of venous invasion and the presence or absence of extrahepatic metastasis. Extrahepatic spread to regional lymph node represent contraindication to surgical resection. Despite the importance of regional node metastasis, their CT appearance is poorly understood. 19 cases of hepatoma collected during Oct, 1982 to May, 1985 at New York Hospital-Cornell Medical center and 73 cases of hepatoma collected during Mar, 1985 to Sept, 1986 at Yonsei University Medical College were reviewed and analysed. Regional lymph node involvement were divided into four main groups with subgrouping according to the location and lymphatic pathway. 1.lymph nodes in lesser omentum: hepatic, portocaval, left gastric and celiac nodes. 2.lymph nodes around pancrease head: subpyloric, superior mesenteric, preaortic retropancreatic, and precaval retropancreatic lymph nodes. 3.paraaortic nodes: left paraaortic, interaorticocaval, retrocaval and preaortic below 3rd duodenum. 4.phrenic nodes: lower parasternal, middle phrenic and retrocrural nodes. The results were as follows: 1.The frequency of regional node involvement, cases collected at New York Hospital-Cornell Medical center, is hepatic node in 5 (26.3%), portocaval node in 8 (42.1%), left gastric in 4 (21.1%), celiac in 7 (36.8%), precaval retropancreatic in 5 (26.3%) preaortic retropancreatic in 4 (21.1%) interaorticocaval in 7 (36.8%) retrocaval in 4 (21.4%) and lower parasternal in (5.3%). 2.The frequency of regional node involvement, cases collected at Yonsei University college of Medicine, is hepatic in 20.5%, portocaval in 24.7% left gastric in 19.2% celiac in 19.2%, precaval retropancreatic in 8.2%, preaortic retropancreatic in 5.5%, left paraaortic in 12.3%, interaorticocaval in 12.3%, retrocaval in 11.0% low parasternal in 0.8%, superior mesenteric in 4.1% subpyloric 1.4% and preaortic below 3rd duodenum in 1

  15. Computed tomographic feature of regional lymph nodes involvement in primary hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki Whang; Kim, Hyung Sik; Lee, Jong Tae; Chung, Tae Sub; Sub, Jung Ho [Yonsei University College of Medicine, Seoul (Korea, Republic of); Auh, Yong Ho [New York Hospital-Cornell Medical Center, (United States)

    1987-04-15

    The resectability of hepatocellular carcinoma is determined by the extent of hepatic involvement, the presence or absence of venous invasion and the presence or absence of extrahepatic metastasis. Extrahepatic spread to regional lymph node represent contraindication to surgical resection. Despite the importance of regional node metastasis, their CT appearance is poorly understood. 19 cases of hepatoma collected during Oct, 1982 to May, 1985 at New York Hospital-Cornell Medical center and 73 cases of hepatoma collected during Mar, 1985 to Sept, 1986 at Yonsei University Medical College were reviewed and analysed. Regional lymph node involvement were divided into four main groups with subgrouping according to the location and lymphatic pathway. 1.lymph nodes in lesser omentum: hepatic, portocaval, left gastric and celiac nodes. 2.lymph nodes around pancrease head: subpyloric, superior mesenteric, preaortic retropancreatic, and precaval retropancreatic lymph nodes. 3.paraaortic nodes: left paraaortic, interaorticocaval, retrocaval and preaortic below 3rd duodenum. 4.phrenic nodes: lower parasternal, middle phrenic and retrocrural nodes. The results were as follows: 1.The frequency of regional node involvement, cases collected at New York Hospital-Cornell Medical center, is hepatic node in 5 (26.3%), portocaval node in 8 (42.1%), left gastric in 4 (21.1%), celiac in 7 (36.8%), precaval retropancreatic in 5 (26.3%) preaortic retropancreatic in 4 (21.1%) interaorticocaval in 7 (36.8%) retrocaval in 4 (21.4%) and lower parasternal in (5.3%). 2.The frequency of regional node involvement, cases collected at Yonsei University college of Medicine, is hepatic in 20.5%, portocaval in 24.7% left gastric in 19.2% celiac in 19.2%, precaval retropancreatic in 8.2%, preaortic retropancreatic in 5.5%, left paraaortic in 12.3%, interaorticocaval in 12.3%, retrocaval in 11.0% low parasternal in 0.8%, superior mesenteric in 4.1% subpyloric 1.4% and preaortic below 3rd duodenum in 1

  16. Accuracy of multidetector-row CT in diagnosing lymph node metastasis in patients with gastric cancer

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Takuro; Kurokawa, Yukinori; Takiguchi, Shuji; Miyazaki, Yasuhiro; Takahashi, Tsuyoshi; Yamasaki, Makoto; Miyata, Hiroshi; Nakajima, Kiyokazu; Mori, Masaki; Doki, Yuichiro [Osaka University, Graduate School of Medicine, Department of Gastroenterological Surgery, Suita, Osaka (Japan)

    2014-08-06

    The purpose of this study was to determine the optimal cut-off value of lymph node size for diagnosing metastasis in gastric cancer with multidetector-row computed tomography (MDCT) after categorizing perigastric lymph nodes into three regions. The study included 90 gastric cancer patients who underwent gastrectomy. The long-axis diameter (LAD) and short-axis diameter (SAD) of all visualized lymph nodes were measured with transverse MDCT images. The locations of lymph nodes were categorized into three regions: lesser curvature, greater curvature, and suprapancreatic. The diagnostic value of lymph node metastasis was assessed with receiver operating characteristic (ROC) analysis. The area under the curve was larger for SAD than LAD in all groups. The optimal cut-off values of SAD were determined as follows: overall, 9 mm; differentiated type, 9 mm; undifferentiated type, 8 mm; lesser curvature region, 7 mm; greater curvature region, 6 mm; and suprapancreatic region, 9 mm. The diagnostic accuracies for lymph node metastasis using individual cut-off values were 71.1 % based on histological type and 76.6 % based on region of lymph node location. The diagnostic accuracy of lymph node metastasis in gastric cancer was improved by using individual cut-off values for each lymph node region. (orig.)

  17. Optimal Node Placement in Underwater Wireless Sensor Networks

    KAUST Repository

    Felamban, M.

    2013-03-25

    Wireless Sensor Networks (WSN) are expected to play a vital role in the exploration and monitoring of underwater areas which are not easily reachable by humans. However, underwater communication via acoustic waves is subject to several performance limitations that are very different from those used for terresstrial networks. In this paper, we investigate node placement for building an initial underwater WSN infrastructure. We formulate this problem as a nonlinear mathematical program with the objective of minimizing the total transmission loss under a given number of sensor nodes and targeted coverage volume. The obtained solution is the location of each node represented via a truncated octahedron to fill out the 3D space. Experiments are conducted to verify the proposed formulation, which is solved using Matlab optimization tool. Simulation is also conducted using an ns-3 simulator, and the simulation results are consistent with the obtained results from mathematical model with less than 10% error.

  18. Cervical lymph node metastasis of oral squamous cell carcinomas. CT enhancement and histopathological evaluations

    Energy Technology Data Exchange (ETDEWEB)

    Etoh, Yohei; Kimura, Takuji; Sasaki, Akira; Kishimoto, Koji; Matsumura, Tomohiro; Kishi, Kanji [Okayama Univ. (Japan). Dental School

    2000-06-01

    A comparison of the results of histopathological and enhanced CT examinations were carried out for 88 patients with oral squamous cell carcinomas who underwent neck dissection. CT scanning (5-mm thick section) images obtained during bolus/drip injection of Iopamidol were routinely taken through the neck. Ninety-two of 1634 nodes were histologically diagnosed as metastatic. Low density areas surrounding enhancement rims were metastatic nodal central necrosis or keratinization. Enhanced areas in many metastatic nodes were considered to be lymphatic architecture, not metastatic masses especially in the avascular keratinization. Enhanced CT produced accurate information of lymph node size, location, shape, grouping and spread from nodes to adjacent structures. However, it was considered that not every metastatic lymph node should show enlargement and/or enhancement. Improved assessment of solid metastatic features of lymph nodes (shape, size, and involvement) may be achieved with the aid of thin-thickness CT. (author)

  19. Cervical lymph node metastasis of oral squamous cell carcinomas. CT enhancement and histopathological evaluations

    International Nuclear Information System (INIS)

    Etoh, Yohei; Kimura, Takuji; Sasaki, Akira; Kishimoto, Koji; Matsumura, Tomohiro; Kishi, Kanji

    2000-01-01

    A comparison of the results of histopathological and enhanced CT examinations were carried out for 88 patients with oral squamous cell carcinomas who underwent neck dissection. CT scanning (5-mm thick section) images obtained during bolus/drip injection of Iopamidol were routinely taken through the neck. Ninety-two of 1634 nodes were histologically diagnosed as metastatic. Low density areas surrounding enhancement rims were metastatic nodal central necrosis or keratinization. Enhanced areas in many metastatic nodes were considered to be lymphatic architecture, not metastatic masses especially in the avascular keratinization. Enhanced CT produced accurate information of lymph node size, location, shape, grouping and spread from nodes to adjacent structures. However, it was considered that not every metastatic lymph node should show enlargement and/or enhancement. Improved assessment of solid metastatic features of lymph nodes (shape, size, and involvement) may be achieved with the aid of thin-thickness CT. (author)

  20. Hub location problems in transportation networks

    DEFF Research Database (Denmark)

    Gelareh, Shahin; Nickel, Stefan

    2011-01-01

    In this paper we propose a 4-index formulation for the uncapacitated multiple allocation hub location problem tailored for urban transport and liner shipping network design. This formulation is very tight and most of the tractable instances for MIP solvers are optimally solvable at the root node....... also introduce fixed cost values for Australian Post (AP) dataset....

  1. Controlling data transfers from an origin compute node to a target compute node

    Science.gov (United States)

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

    2011-06-21

    Methods, apparatus, and products are disclosed for controlling data transfers from an origin compute node to a target compute node that include: receiving, by an application messaging module on the target compute node, an indication of a data transfer from an origin compute node to the target compute node; and administering, by the application messaging module on the target compute node, the data transfer using one or more messaging primitives of a system messaging module in dependence upon the indication.

  2. Estimation of Distributed Fermat-Point Location for Wireless Sensor Networking

    Directory of Open Access Journals (Sweden)

    Yanuarius Teofilus Larosa

    2011-04-01

    Full Text Available This work presents a localization scheme for use in wireless sensor networks (WSNs that is based on a proposed connectivity-based RF localization strategy called the distributed Fermat-point location estimation algorithm (DFPLE. DFPLE applies triangle area of location estimation formed by intersections of three neighboring beacon nodes. The Fermat point is determined as the shortest path from three vertices of the triangle. The area of estimated location then refined using Fermat point to achieve minimum error in estimating sensor nodes location. DFPLE solves problems of large errors and poor performance encountered by localization schemes that are based on a bounding box algorithm. Performance analysis of a 200-node development environment reveals that, when the number of sensor nodes is below 150, the mean error decreases rapidly as the node density increases, and when the number of sensor nodes exceeds 170, the mean error remains below 1% as the node density increases. Second, when the number of beacon nodes is less than 60, normal nodes lack sufficient beacon nodes to enable their locations to be estimated. However, the mean error changes slightly as the number of beacon nodes increases above 60. Simulation results revealed that the proposed algorithm for estimating sensor positions is more accurate than existing algorithms, and improves upon conventional bounding box strategies.

  3. Estimation of distributed Fermat-point location for wireless sensor networking.

    Science.gov (United States)

    Huang, Po-Hsian; Chen, Jiann-Liang; Larosa, Yanuarius Teofilus; Chiang, Tsui-Lien

    2011-01-01

    This work presents a localization scheme for use in wireless sensor networks (WSNs) that is based on a proposed connectivity-based RF localization strategy called the distributed Fermat-point location estimation algorithm (DFPLE). DFPLE applies triangle area of location estimation formed by intersections of three neighboring beacon nodes. The Fermat point is determined as the shortest path from three vertices of the triangle. The area of estimated location then refined using Fermat point to achieve minimum error in estimating sensor nodes location. DFPLE solves problems of large errors and poor performance encountered by localization schemes that are based on a bounding box algorithm. Performance analysis of a 200-node development environment reveals that, when the number of sensor nodes is below 150, the mean error decreases rapidly as the node density increases, and when the number of sensor nodes exceeds 170, the mean error remains below 1% as the node density increases. Second, when the number of beacon nodes is less than 60, normal nodes lack sufficient beacon nodes to enable their locations to be estimated. However, the mean error changes slightly as the number of beacon nodes increases above 60. Simulation results revealed that the proposed algorithm for estimating sensor positions is more accurate than existing algorithms, and improves upon conventional bounding box strategies.

  4. Secure message authentication system for node to node network

    Science.gov (United States)

    Sindhu, R.; Vanitha, M. M.; Norman, J.

    2017-10-01

    The Message verification remains some of the best actual methods for prevent the illegal and dis honored communication after presence progressed to WSNs (Wireless Sensor Networks). Intend for this purpose, several message verification systems must stand established, created on both symmetric key cryptography otherwise public key cryptosystems. Best of them will have some limits for great computational then statement above in count of deficiency of climb ability then flexibility in node settlement occurrence. In a polynomial based system was newly presented for these problems. Though, this system then situations delay will must the dimness of integral limitation firm in the point of polynomial: once the amount of message transferred remains the greater than the limitation then the opponent will completely improve the polynomial approaches. This paper suggests using ECC (Elliptic Curve Cryptography). Though using the node verification the technique in this paper permits some nodes to transfer a limitless amount of messages lacking misery in the limit problem. This system will have the message cause secrecy. Equally theoretic study then model effects show our planned system will be effective than the polynomial based method in positions of calculation then statement above in privacy points though message basis privacy.

  5. Normal mediastinal and hilar lymph nodes in children on multi-detector row chest computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Jong, Pim A. de; Nievelstein, Rutger-Jan A. [University Medical Center Utrecht and Wilhelmina Children' s Hospital, Department of Radiology, Utrecht (Netherlands)

    2012-02-15

    To study normal mediastinal and hilar lymph nodes on multi-detector chest computed tomography (CT). A cohort of 120 children aged 1-17 years underwent emergency CT, including the chest, after high-energy trauma. Axial 5-mm reconstructions were evaluated for lymph nodes at hilar and various mediastinal levels and the short-axis diameters were measured. At least one lymph node was found in 115 (96%) children, with subcarinal (69%), lower paratracheal (64%) and hilar (60%) nodes being most common. Up to 10 years of age most lymph nodes were smaller than or equal to 7 mm. In older children lymph nodes measuring up to 10-mm-short-axis diameter were found. Lymph nodes were rare along the mammary vessels, at lower oesophageal and at prevascular and posterior mediastinal levels in children. Mediastinal and hilar lymph nodes are more common than previously thought, probably because of increased detection by modern multi-detector CT. Lymph node location and age have to be taken into account when evaluating lymph nodes in the paediatric chest. (orig.)

  6. Normal mediastinal and hilar lymph nodes in children on multi-detector row chest computed tomography

    International Nuclear Information System (INIS)

    Jong, Pim A. de; Nievelstein, Rutger-Jan A.

    2012-01-01

    To study normal mediastinal and hilar lymph nodes on multi-detector chest computed tomography (CT). A cohort of 120 children aged 1-17 years underwent emergency CT, including the chest, after high-energy trauma. Axial 5-mm reconstructions were evaluated for lymph nodes at hilar and various mediastinal levels and the short-axis diameters were measured. At least one lymph node was found in 115 (96%) children, with subcarinal (69%), lower paratracheal (64%) and hilar (60%) nodes being most common. Up to 10 years of age most lymph nodes were smaller than or equal to 7 mm. In older children lymph nodes measuring up to 10-mm-short-axis diameter were found. Lymph nodes were rare along the mammary vessels, at lower oesophageal and at prevascular and posterior mediastinal levels in children. Mediastinal and hilar lymph nodes are more common than previously thought, probably because of increased detection by modern multi-detector CT. Lymph node location and age have to be taken into account when evaluating lymph nodes in the paediatric chest. (orig.)

  7. [Utility and advantages of single tracer subareolar injection in sentinel lymph node biopsy in breast cancer].

    Science.gov (United States)

    Armas, Fayna; Hernández, María Jesús; Vega, Víctor; Gutiérrez, Isabel; Jiménez, Concepción; Pavcovich, Marta; Báez, Beatriz; Pérez-Correa, Pedro; Núñez, Valentín

    2005-10-01

    Sentinel lymph node (SLN) biopsy is a reliable technique for determining axillary status in patients with early breast cancer. This technique is a minimally invasive procedure that can avoid the use of lymphadenectomy in patients without axillary involvement. We present a validation study of SLN biopsy with subareolar injection of 99mTc-nanocolloids. We studied 100 patients with early breast cancer (T1 and T2) over a 2-year period. All patients underwent deep subareolar-injection of 99mTc-nanocoloid for localization of the sentinel node. Images were obtained and when the sentinel node was seen, it was marked on the skin. All patients underwent tumor excision and radioguided SLN biopsy followed by complete lymphadenectomy. Histopathological analysis of sentinel nodes was performed by hematoxylin-eosin and immunohistochemistry with cytokeratins. The sentinel node was identified in all patients, and a mean of 1.95 sentinel nodes per patient were found. Lymphatic metastases in the sentinel node were found in 44 patients and in 15 of these tumoral spread was also found in the remaining axillary nodes. In the 56 remaining patients the sentinel node was free of metastasis, but in two of them a non-sentinel node was found to be positive (4.5% false negative rate). Sensitivity was 95.7% (44/46), specificity was 100% (54/54), the positive predictive value was 100% and the negative predictive value was 96.4% (54/56). SLN biopsy is an accurate alternative to complete axillary lymph node dissection in patients with early-stage breast cancer. This technique improves the staging of these patients and decreases the morbidity associated with lymphadenectomy. The advantages of subareolar injection are that a single injection site is required, the tumor does not have to be located by other techniques, it allows rapid visualization of the sentinel node and avoids the "shine through phenomenon" when the tumor is located near the axilla.

  8. Computational lymphatic node models in pediatric and adult hybrid phantoms for radiation dosimetry

    International Nuclear Information System (INIS)

    Lee, Choonsik; Lamart, Stephanie; Moroz, Brian E

    2013-01-01

    We developed models of lymphatic nodes for six pediatric and two adult hybrid computational phantoms to calculate the lymphatic node dose estimates from external and internal radiation exposures. We derived the number of lymphatic nodes from the recommendations in International Commission on Radiological Protection (ICRP) Publications 23 and 89 at 16 cluster locations for the lymphatic nodes: extrathoracic, cervical, thoracic (upper and lower), breast (left and right), mesentery (left and right), axillary (left and right), cubital (left and right), inguinal (left and right) and popliteal (left and right), for different ages (newborn, 1-, 5-, 10-, 15-year-old and adult). We modeled each lymphatic node within the voxel format of the hybrid phantoms by assuming that all nodes have identical size derived from published data except narrow cluster sites. The lymph nodes were generated by the following algorithm: (1) selection of the lymph node site among the 16 cluster sites; (2) random sampling of the location of the lymph node within a spherical space centered at the chosen cluster site; (3) creation of the sphere or ovoid of tissue representing the node based on lymphatic node characteristics defined in ICRP Publications 23 and 89. We created lymph nodes until the pre-defined number of lymphatic nodes at the selected cluster site was reached. This algorithm was applied to pediatric (newborn, 1-, 5-and 10-year-old male, and 15-year-old males) and adult male and female ICRP-compliant hybrid phantoms after voxelization. To assess the performance of our models for internal dosimetry, we calculated dose conversion coefficients, called S values, for selected organs and tissues with Iodine-131 distributed in six lymphatic node cluster sites using MCNPX2.6, a well validated Monte Carlo radiation transport code. Our analysis of the calculations indicates that the S values were significantly affected by the location of the lymph node clusters and that the values increased for

  9. Mobile agent location in distributed environments

    Science.gov (United States)

    Fountoukis, S. G.; Argyropoulos, I. P.

    2012-12-01

    An agent is a small program acting on behalf of a user or an application which plays the role of a user. Artificial intelligence can be encapsulated in agents so that they can be capable of both behaving autonomously and showing an elementary decision ability regarding movement and some specific actions. Therefore they are often called autonomous mobile agents. In a distributed system, they can move themselves from one processing node to another through the interconnecting network infrastructure. Their purpose is to collect useful information and to carry it back to their user. Also, agents are used to start, monitor and stop processes running on the individual interconnected processing nodes of computer cluster systems. An agent has a unique id to discriminate itself from other agents and a current position. The position can be expressed as the address of the processing node which currently hosts the agent. Very often, it is necessary for a user, a processing node or another agent to know the current position of an agent in a distributed system. Several procedures and algorithms have been proposed for the purpose of position location of mobile agents. The most basic of all employs a fixed computing node, which acts as agent position repository, receiving messages from all the moving agents and keeping records of their current positions. The fixed node, responds to position queries and informs users, other nodes and other agents about the position of an agent. Herein, a model is proposed that considers pairs and triples of agents instead of single ones. A location method, which is investigated in this paper, attempts to exploit this model.

  10. Data acquisition remote node powered over the communications optical fiber

    International Nuclear Information System (INIS)

    Batista, Antonio J.N.; Sousa, Jorge; Gonçalves, Bruno

    2015-01-01

    Large nuclear fusion reactors, like ITER, will have harsh electromagnetic environments nearby the machine. Foreseeing the necessity for special data acquisition remote nodes, on difficult access locations and as close as possible to the experimental devices, motivated the system design. The architecture is based on the power-over-fiber technology recent advancements and respective implementation aim is to attain a proof of concept for the fusion technology field and others, e.g., high energy physics, industry, etc. The design intends the replacement of traditional copper cables and power supplies, vulnerable to electromagnetic interference, by the communications optical fiber of the data acquisition remote node. Optical fibers provide galvanic isolation, immunity to noisy electromagnetic environments and simultaneously can supply power to the remote node electronics. System architecture uses a laser power converter (array of photovoltaic cells) to convert the laser light, from the optical fiber, into electricity. The generated electrical power is enough for powering the remote node electronics and optoelectronics, such as an ADC, a low power FPGA and an optical transmitter. The laser power converter is also used as the communications receiver and from which the acquisition clock is recovered, providing synchronism between remote data acquisition nodes. Descriptions of the system architecture, tested implementations and future improvements are presented.

  11. Optimal Node Placement in Underwater Acoustic Sensor Network

    KAUST Repository

    Felemban, Muhamad

    2011-10-01

    Almost 70% of planet Earth is covered by water. A large percentage of underwater environment is unexplored. In the past two decades, there has been an increase in the interest of exploring and monitoring underwater life among scientists and in industry. Underwater operations are extremely difficult due to the lack of cheap and efficient means. Recently, Wireless Sensor Networks have been introduced in underwater environment applications. However, underwater communication via acoustic waves is subject to several performance limitations, which makes the relevant research issues very different from those on land. In this thesis, we investigate node placement for building an initial Underwater Wireless Sensor Network infrastructure. Firstly, we formulated the problem into a nonlinear mathematic program with objectives of minimizing the total transmission loss under a given number of sensor nodes and targeted volume. We conducted experiments to verify the proposed formulation, which is solved using Matlab optimization tool. We represented each node with a truncated octahedron to fill out the 3D space. The truncated octahedrons are tiled in the 3D space with each node in the center where locations of the nodes are given using 3D coordinates. Results are supported using ns-3 simulator. Results from simulation are consistent with the obtained results from mathematical model with less than 10% error.

  12. Detecting Boundary Nodes and Coverage Holes in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Li-Hui Zhao

    2016-01-01

    Full Text Available The emergence of coverage holes in wireless sensor networks (WSNs means that some special events have broken out and the function of WSNs will be seriously influenced. Therefore, the issues of coverage holes have attracted considerable attention. In this paper, we focus on the identification of boundary nodes and coverage holes, which is crucially important to preventing the enlargement of coverage holes and ensuring the transmission of data. We define the problem of coverage holes and propose two novel algorithms to identify the coverage holes in WSNs. The first algorithm, Distributed Sector Cover Scanning (DSCS, can be used to identify the nodes on hole borders and the outer boundary of WSNs. The second scheme, Directional Walk (DW, can locate the coverage holes based on the boundary nodes identified with DSCS. We implement the algorithms in various scenarios and fully evaluate their performance. The simulation results show that the boundary nodes can be accurately detected by DSCS and the holes enclosed by the detected boundary nodes can be identified by DW. The comparisons confirm that the proposed algorithms outperform the existing ones.

  13. Entanglement swapping with independent sources over an optical-fiber network

    Science.gov (United States)

    Sun, Qi-Chao; Mao, Ya-Li; Jiang, Yang-Fan; Zhao, Qi; Chen, Si-Jing; Zhang, Wei; Zhang, Wei-Jun; Jiang, Xiao; Chen, Teng-Yun; You, Li-Xing; Li, Li; Huang, Yi-Dong; Chen, Xian-Feng; Wang, Zhen; Ma, Xiongfeng; Zhang, Qiang; Pan, Jian-Wei

    2017-03-01

    Establishing entanglement between two remote systems by the method of entanglement swapping is an essential step for a long-distance quantum network. Here we report a field-test entanglement swapping experiment with two independent telecommunication band entangled photon-pair sources over an optical fiber network in Hefei. The two sources are located at two nodes that are 12.5 km apart and the Bell-state measurement is performed at a third location which is connected to the two source nodes with 14.7-km and 10.6-km optical fibers, respectively. The observed average visibility is 79.9 ±4.8 % , which is sufficient for the violation of Bell inequalities. Furthermore, with the swapped entanglement, we demonstrate a source-independent quantum key distribution, which is also immune to any detection attacks at the measurement site.

  14. On the benefits of location-based relay selection in mobile wireless networks

    DEFF Research Database (Denmark)

    Nielsen, Jimmy Jessen; Madsen, Tatiana Kozlova; Schwefel, Hans-Peter

    2016-01-01

    We consider infrastructure-based mobile networks that are assisted by a single relay transmission where both the downstream destination and relay nodes are mobile. Selecting the optimal transmission path for a destination node requires up-to-date link quality estimates of all relevant links....... If the relay selection is based on link quality measurements, the number of links to update grows quadratically with the number of nodes, and measurements need to be updated frequently when nodes are mobile. In this paper, we consider a location-based relay selection scheme where link qualities are estimated...... from node positions; in the scenario of a node-based location system such as GPS, the location-based approach reduces signaling overhead, which in this case only grows linearly with the number of nodes. This paper studies these two relay selection approaches and investigates how they are affected...

  15. Codimension n saddle-nodes

    International Nuclear Information System (INIS)

    Gheiner, Jaques

    2014-01-01

    We consider the generic unfolding of a diffeomorphism on a compact C ∞ manifold that is Morse–Smale except for one non-hyperbolic periodic orbit being a codimension n saddle-node (one eigenvalue is 1, the other eigenvalues have norm different from 1). Local and global bifurcations are described. We characterize structural stability of the unfolding, depending on the codimension. A universal model of the unfolding is given when there is stability. Dynamical behaviour is analysed in other cases. (paper)

  16. Sentinel node biopsy in penile cancer

    DEFF Research Database (Denmark)

    Jakobsen, J. K.; Krarup, K. P.; Sommer, P.

    2015-01-01

    INTRODUCTION & OBJECTIVES: Nodal involvement is a strong prognosticator in penile cancer and lymph node staging is crucial. Sentinel node biopsy (SNB) has proven a useful staging tool with few complications, but evidence rely mostly on single institution publications with a short follow-up. In th......INTRODUCTION & OBJECTIVES: Nodal involvement is a strong prognosticator in penile cancer and lymph node staging is crucial. Sentinel node biopsy (SNB) has proven a useful staging tool with few complications, but evidence rely mostly on single institution publications with a short follow...... died from complications. CONCLUSIONS: To our knowledge, this is the first complete national study on sentinel node biopsy. Penile cancer sentinel node biopsy with a close follow-up is a reliable lymph node staging and has few complications in a national multicentre setting. Inguinal lymph node...

  17. Axillary Lymph Nodes and Breast Cancer

    Science.gov (United States)

    ... white blood cells that help fight illness. If breast cancer spreads, the lymph nodes in the underarm (called ... if they contain cancer cells. This helps determine breast cancer stage and guide treatment. Sentinel node biopsy and ...

  18. Sentinel Node in Oral Cancer

    DEFF Research Database (Denmark)

    Tartaglione, Girolamo; Stoeckli, Sandro J; de Bree, Remco

    2016-01-01

    /static scan and/or SPECT/CT. RESULTS: Lymphoscintigraphy identified 723 lymphatic basins. 1398 sentinel lymph nodes (SNs) were biopsied (3.2 SN per patient; range, 1-10). Dynamic scan allowed the differentiation of sentinel nodes from second tier lymph nodes. SPECT/CT allowed more accurate anatomical......PURPOSE: Nuclear imaging plays a crucial role in lymphatic mapping of oral cancer. This evaluation represents a subanalysis of the original multicenter SENT trial data set, involving 434 patients with T1-T2, N0, and M0 oral squamous cell carcinoma. The impact of acquisition techniques, tracer...... localization and estimated SN depth more efficiently. After pathological examination, 9.9% of the SN excised (138 of 1398 SNs) showed metastases. The first neck level (NL) containing SN+ was NL I in 28.6%, NL IIa in 44.8%, NL IIb in 2.8%, NL III in 17.1%, and NL IV in 6.7% of positive patients. Approximately...

  19. Lymph Node Metastases and Prognosis in Left Upper Division Non-Small Cell Lung Cancers: The Impact of Interlobar Lymph Node Metastasis

    Science.gov (United States)

    Kuroda, Hiroaki; Sakao, Yukinori; Mun, Mingyon; Uehara, Hirofumi; Nakao, Masayuki; Matsuura, Yousuke; Mizuno, Tetsuya; Sakakura, Noriaki; Motoi, Noriko; Ishikawa, Yuichi; Yatabe, Yasushi; Nakagawa, Ken; Okumura, Sakae

    2015-01-01

    Background Left upper division segmentectomy is one of the major pulmonary procedures; however, it is sometimes difficult to completely dissect interlobar lymph nodes. We attempted to clarify the prognostic importance of hilar and mediastinal nodes, especially of interlobar lymph nodes, in patients with primary non-small cell lung cancer (NSCLC) located in the left upper division. Methods We retrospectively studied patients with primary left upper lobe NSCLC undergoing surgical pulmonary resection (at least lobectomy) with radical lymphadenectomy. The representative evaluation of therapeutic value from the lymph node dissection was determined using Sasako’s method. This analysis was calculated by multiplying the frequency of metastasis to the station and the 5-year survival rate of the patients with metastasis to the station. Results We enrolled 417 patients (237 men, 180 women). Tumors were located in the lingular lobe and at the upper division of left upper lobe in 69 and 348 patients, respectively. The pathological nodal statuses were pN0 in 263 patients, pN1 in 70 patients, and pN2 in 84 patients. Lymph nodes #11 and #7 were significantly correlated with differences in node involvement in patients with left upper lobe NSCLC. Among those with left upper division NSCLC, the 5-year overall survival in pN1 was 31.5% for #10, 39.3% for #11, and 50.4% for #12U. The involvement of node #11 was 1.89-fold higher in the anterior segment than that in the apicoposterior segment. The therapeutic index of estimated benefit from lymph node dissection for #11 was 3.38, #4L was 1.93, and the aortopulmonary window was 4.86 in primary left upper division NSCLC. Conclusions Interlobar node involvement is not rare in left upper division NSCLC, occurring in >20% cases. Furthermore, dissection of interlobar nodes was found to be beneficial in patients with left upper division NSCLC. PMID:26247881

  20. Lymph Node Metastases and Prognosis in Left Upper Division Non-Small Cell Lung Cancers: The Impact of Interlobar Lymph Node Metastasis.

    Directory of Open Access Journals (Sweden)

    Hiroaki Kuroda

    Full Text Available Left upper division segmentectomy is one of the major pulmonary procedures; however, it is sometimes difficult to completely dissect interlobar lymph nodes. We attempted to clarify the prognostic importance of hilar and mediastinal nodes, especially of interlobar lymph nodes, in patients with primary non-small cell lung cancer (NSCLC located in the left upper division.We retrospectively studied patients with primary left upper lobe NSCLC undergoing surgical pulmonary resection (at least lobectomy with radical lymphadenectomy. The representative evaluation of therapeutic value from the lymph node dissection was determined using Sasako's method. This analysis was calculated by multiplying the frequency of metastasis to the station and the 5-year survival rate of the patients with metastasis to the station.We enrolled 417 patients (237 men, 180 women. Tumors were located in the lingular lobe and at the upper division of left upper lobe in 69 and 348 patients, respectively. The pathological nodal statuses were pN0 in 263 patients, pN1 in 70 patients, and pN2 in 84 patients. Lymph nodes #11 and #7 were significantly correlated with differences in node involvement in patients with left upper lobe NSCLC. Among those with left upper division NSCLC, the 5-year overall survival in pN1 was 31.5% for #10, 39.3% for #11, and 50.4% for #12U. The involvement of node #11 was 1.89-fold higher in the anterior segment than that in the apicoposterior segment. The therapeutic index of estimated benefit from lymph node dissection for #11 was 3.38, #4L was 1.93, and the aortopulmonary window was 4.86 in primary left upper division NSCLC.Interlobar node involvement is not rare in left upper division NSCLC, occurring in >20% cases. Furthermore, dissection of interlobar nodes was found to be beneficial in patients with left upper division NSCLC.

  1. Lymph node detection in IASLC-defined zones on PET/CT images

    Science.gov (United States)

    Song, Yihua; Udupa, Jayaram K.; Odhner, Dewey; Tong, Yubing; Torigian, Drew A.

    2016-03-01

    Lymph node detection is challenging due to the low contrast between lymph nodes as well as surrounding soft tissues and the variation in nodal size and shape. In this paper, we propose several novel ideas which are combined into a system to operate on positron emission tomography/ computed tomography (PET/CT) images to detect abnormal thoracic nodes. First, our previous Automatic Anatomy Recognition (AAR) approach is modified where lymph node zones predominantly following International Association for the Study of Lung Cancer (IASLC) specifications are modeled as objects arranged in a hierarchy along with key anatomic anchor objects. This fuzzy anatomy model built from diagnostic CT images is then deployed on PET/CT images for automatically recognizing the zones. A novel globular filter (g-filter) to detect blob-like objects over a specified range of sizes is designed to detect the most likely locations and sizes of diseased nodes. Abnormal nodes within each automatically localized zone are subsequently detected via combined use of different items of information at various scales: lymph node zone model poses found at recognition indicating the geographic layout at the global level of node clusters, g-filter response which hones in on and carefully selects node-like globular objects at the node level, and CT and PET gray value but within only the most plausible nodal regions for node presence at the voxel level. The models are built from 25 diagnostic CT scans and refined for an object hierarchy based on a separate set of 20 diagnostic CT scans. Node detection is tested on an additional set of 20 PET/CT scans. Our preliminary results indicate node detection sensitivity and specificity at around 90% and 85%, respectively.

  2. The hidden sentinel node in breast cancer

    NARCIS (Netherlands)

    Tanis, P. J.; van Sandick, J. W.; Nieweg, O. E.; Valdés Olmos, R. A.; Rutgers, E. J. T.; Hoefnagel, C. A.; Kroon, B. B. R.

    2002-01-01

    The purpose of this study was to analyse the occurrence of non-visualisation during preoperative lymphoscintigraphy for sentinel node identification in breast cancer. Preoperative lymphoscintigraphy was performed in 495 clinically node-negative breast cancer patients (501 sentinel node procedures)

  3. T.Node, industrial version of supernode

    Science.gov (United States)

    Flieller, Sylvain

    1989-12-01

    The Esprit I P1085 "SuperNode" project developed a modular reconfigurable archtecture, based on transputers. This highly parallel machine is now marketed by Telmat Informatique under the name T.Node. This paper presents the P1085 project, the architecture of SuperNode, its industrial implementation and its software enviroment.

  4. CT perfusion study of neck lymph nodes

    International Nuclear Information System (INIS)

    Zhong Jin; Liu Jun; Hua Rui; Qiao Hui; Gong Yi

    2011-01-01

    Objective: To study the CT perfusion features of various lymph nodes in the neck. Methods: Dynamic perfusion CT scanning was performed in 83 neck lymph nodes proved by pathology, including tuberculosis lymph nodes, lymphoma and metastatic lymph nodes. The shapes, blood flow modes, and perfusion parameters of these lymph nodes were compared among 3 groups. Statistical analysis of L/T and CT perfusion parameters was performed by one-way ANOVA and LSD test. Results: The values of MTT of tuberculosis lymph nodes, lymphoma and metastatic lymph nodes were (28.13±5.08), (31.08±5.82), and (11.24±5.31) s, respectively. The MTT of metastatic lymph nodes was statistically lower than that of tuberculosis lymph nodes and lymphoma (P -1 · 100 g -1 , respectively. The values of BV were (24.68±2.84), (25.30±3.16), and (25.15± 8.81) ml·100 g -1 respectively. The values of TTP were (40.90±8.85), (40.67±6.45), and (40.98±6.62) s, respectively. There were no significant differences in L/T, BF, BV and TTP among tuberculosis lymph nodes, lymphoma and metastatic lymph nodes (P>0.05). Conclusion: CT perfusion, especially combination functional imaging with perfusion images may be helpful in judging the nature of neck lymph nodes. (authors)

  5. Sentinel node concept in breast cancer

    International Nuclear Information System (INIS)

    Kiricuta, I.C.

    2000-01-01

    Background/purpose: It seems that there exists a specific lymph node center called sentinel node (SN) which appears to be the primary site of metastases. The sentinel node concept (SNC) is fundamentally based on the orderly progression of tumor cells within the lymphatic system. It is the most important new concept in surgical and radiation oncology. The purpose is to present the biological significance, the diagnostic and clinical basis of the sentinel node concept in breast cancer patients. Material and methods: Lymphoscintigraphy and gamma probe biopsy is necessary to show predictable lymph flow to the regional sentinel node, to multiple sentinel nodes or unpredictable lymph flow to extra-regional sentinel nodes and for performing sentinel node procedure. The standard protocol for the evaluation of the sentinel node metastases consists of extensive histopathological investigation including step Hematoxylin and Eosin (H and E) stained sections and immunohistochemistry. Results: A high rate of success of the identification of the sentinel node for breast cancer was reported. The presence or absence of metastasis in this node is a very accurate predictor of overall nodal status. The temptation to examine the sentinel node with the greatest possible degree of accuracy highlights one of the major problems related to sentinel node biopsy. The success of the sentinel node procedure depends primarily on the adequate functional capacity necessary for sufficient uptake to ensure the accurate identification. In negative sentinel-node patients a complete axillary lymph node dissection is avoidable. In sentinel-node positive patients and clinically negative patients a postoperative radiotherapy would permit an adequate tumor control. The last 2-procedures permit a low morbidity. In the actual TNM classification it was recently introduced a definition of a 'pN0' patient based on sentinel node biopsy. New target volumes are defined for adjuvant radiotherapy or lymphatic basins

  6. High risk of non-sentinel node metastases in a group of breast cancer patients with micrometastases in the sentinel node.

    Science.gov (United States)

    Tvedskov, Tove Filtenborg; Jensen, Maj-Britt; Lisse, Ida Marie; Ejlertsen, Bent; Balslev, Eva; Kroman, Niels

    2012-11-15

    Axillary lymph node dissection (ALND) in breast cancer patients with positive sentinel nodes is under debate. We aimed to establish two models to predict non-sentinel node (NSN) metastases in patients with micrometastases or isolated tumor cells (ITC) in sentinel nodes, to guide the decision for ALND. A total of 1,577 breast cancer patients with micrometastases and 304 with ITC in sentinel nodes, treated by sentinel lymph node dissection and ALND in 2002-2008 were identified in the Danish Breast Cancer Cooperative Group database. Risk of NSN metastases was calculated according to clinicopathological variables in a logistic regression analysis. We identified tumor size, proportion of positive sentinel nodes, lymphovascular invasion, hormone receptor status and location of tumor in upper lateral quadrant of the breast as risk factors for NSN metastases in patients with micrometastases. A model based on these risk factors identified 5% of patients with a risk of NSN metastases on nearly 40%. The model was however unable to identify a subgroup of patients with a very low risk of NSN metastases. Among patients with ITC, we identified tumor size, age and proportion of positive sentinel nodes as risk factors. A model based on these risk factors identified 32% of patients with risk of NSN metastases on only 2%. Omission of ALND would be acceptable in this group of patients. In contrast, ALND may still be beneficial in the subgroup of patients with micrometastases and a high risk of NSN metastases. Copyright © 2012 UICC.

  7. Operating Wireless Sensor Nodes without Energy Storage: Experimental Results with Transient Computing

    Directory of Open Access Journals (Sweden)

    Faisal Ahmed

    2016-12-01

    Full Text Available Energy harvesting is increasingly used for powering wireless sensor network nodes. Recently, it has been suggested to combine it with the concept of transient computing whereby the wireless sensor nodes operate without energy storage capabilities. This new combined approach brings benefits, for instance ultra-low power nodes and reduced maintenance, but also raises new challenges, foremost dealing with nodes that may be left without power for various time periods. Although transient computing has been demonstrated on microcontrollers, reports on experiments with wireless sensor nodes are still scarce in the literature. In this paper, we describe our experiments with solar, thermal, and RF energy harvesting sources that are used to power sensor nodes (including wireless ones without energy storage, but with transient computing capabilities. The results show that the selected solar and thermal energy sources can operate both the wired and wireless nodes without energy storage, whereas in our specific implementation, the developed RF energy source can only be used for the selected nodes without wireless connectivity.

  8. Impact of clinical pharmacy interventions on medication error nodes.

    Science.gov (United States)

    Chamoun, Nibal R; Zeenny, Rony; Mansour, Hanine

    2016-12-01

    Background Pharmacists' involvement in patient care has improved the quality of care and reduced medication errors. However, this has required a lot of work that could not have been accomplished without documentation of interventions. Several means of documenting errors have been proposed in the literature but without a consistent comprehensive process. Recently, the American College of Clinical Pharmacy (ACCP) recognized that pharmacy practice lacks a consistent process for direct patient care and discussed several options for a pharmaceutical care plan, essentially encompassing medication therapy assessment, development and implementation of a pharmaceutical care plan and finally evaluation of the outcome. Therefore, as per the recommendations of ACCP, we sought to retrospectively analyze interventions by grouping them according to medication related problems (MRP) and their nodes such as prescribing; administering; monitoring; documenting and dispensing. Objective The aim of this study is to report interventions according to medication error (ME) nodes and show the impact of pharmacy interventions in reducing MRPs. Setting The study was conducted at the cardiology and infectious diseases services at a teaching hospital located in Beirut, Lebanon. Methods Intervention documentation was completed by pharmacy students on infectious diseases and cardiology rotations then reviewed by clinical pharmacists with respective specialties. Before data analysis, a new pharmacy reporting sheet was developed in order to link interventions according to MRP. Then, MRPs were grouped in the five ME nodes. During the documentation process, whether MRP had reached the patient or not may have not been reported which prevented the classification to the corresponding medication error nodes as ME. Main outcome Reduction in medication related problems across all ME nodes. Results A total of n = 1174 interventions were documented. N = 1091 interventions were classified as MRPs

  9. Offloading of a Wireless Node Authentication with Core Network

    DEFF Research Database (Denmark)

    2017-01-01

    An example technique may include controlling receiving, by a second node from a first node in a wireless network, a request to offload authentication of the first node with the core network to the second node, controlling receiving, by the second node from the first node, data to be forwarded...... to the core network, performing, by the second node based on the request, an authentication with the core network on behalf of the first node while the first node is not connected with the second node, and controlling forwarding the received data from the second node to the core network while the first node...

  10. An Energy Efficient Simultaneous-Node Repositioning Algorithm for Mobile Sensor Networks

    Science.gov (United States)

    Hasbullah, Halabi; Nazir, Babar; Khan, Imran Ali

    2014-01-01

    Recently, wireless sensor network (WSN) applications have seen an increase in interest. In search and rescue, battlefield reconnaissance, and some other such applications, so that a survey of the area of interest can be made collectively, a set of mobile nodes is deployed. Keeping the network nodes connected is vital for WSNs to be effective. The provision of connectivity can be made at the time of startup and can be maintained by carefully coordinating the nodes when they move. However, if a node suddenly fails, the network could be partitioned to cause communication problems. Recently, several methods that use the relocation of nodes for connectivity restoration have been proposed. However, these methods have the tendency to not consider the potential coverage loss in some locations. This paper addresses the concerns of both connectivity and coverage in an integrated way so that this gap can be filled. A novel algorithm for simultaneous-node repositioning is introduced. In this approach, each neighbour of the failed node, one by one, moves in for a certain amount of time to take the place of the failed node, after which it returns to its original location in the network. The effectiveness of this algorithm has been verified by the simulation results. PMID:25152924

  11. A critical reappraisal of false negative sentinel lymph node biopsy in melanoma

    International Nuclear Information System (INIS)

    Manca, G.; Mazzarri, S.; Boni, G.; Chiacchio, S.; Tredici, M.; Duce, V.; Tardelli, E.; Volterrani, D.; Mariani, G.; Romanini, A.; Rubello, D.

    2014-01-01

    Lymphatic mapping and sentinel lymph node biopsy (SLNB) have completely changed the clinical management of cutaneous melanoma. This procedure has been accepted worldwide as a recognized method for nodal staging. SLNB is able to accurately determine nodal basin status, providing the most useful prognostic information. However, SLNB is not a perfect diagnostic test. Several large-scale studies have reported a relatively high false-negative rate (5.6-21%), correctly defined as the proportion of false-negative results with respect to the total number of “actual” positive lymph nodes. The main purpose of this review is to address the technical issues that nuclear physicians, surgeons, and pathologists should carefully consider to improve the accuracy of SLNB by minimizing its false-negative rate. In particular, SPECT/CT imaging has demonstrated to be able to identify a greater number of sentinel lymph nodes (SLNs) than those found by planar lymphoscintigraphy. Furthermore, a unique definition in the international guidelines is missing for the operational identification of SLNs, which may be partly responsible for this relatively high false-negative rate of SLNB. Therefore, it is recommended for the scientific community to agree on the radioactive counting rate threshold so that the surgeon can be better radioguided to detect all the lymph nodes which are most likely to harbor metastases. Another possible source of error may be linked to the examination of the harvested SLNs by conventional histopathological methods. A more careful and extensive SLN analysis (e.g. molecular analysis by RT-PCR) is able to find more positive nodes, so that the false-negative rate is reduced. Older age at diagnosis, deeper lesions, histologic ulceration, head-neck anatomical location of primary lesions are the clinical factors associated with false-negative SLNBs in melanoma patients. There is still much controversy about the clinical significance of a false-negative SLNB on the

  12. Sentinel lymph node biopsy in oral cancer

    DEFF Research Database (Denmark)

    Thomsen, Jørn Bo; Sørensen, Jens Ahm; Grupe, Peter

    2005-01-01

    PURPOSE: To validate lymphatic mapping combined with sentinel lymph node biopsy as a staging procedure, and to evaluate the possible clinical implications of added oblique lymphoscintigraphy and/or tomography and test the intra- and interobserver reproducibility of lymphoscintigraphy. MATERIAL......: Eleven (28%) patients were upstaged. The sentinel lymph node identification rate was 97.5%. Sentinel lymph node biopsy significantly differentiated between patients with or without lymph node metastasis (P = 0.001). Lymphatic mapping revealed 124 hotspots and 144 hot lymph nodes were removed by sentinel...

  13. Hidradenocarcinoma of the Scrotum with Lymph Node Metastasis

    OpenAIRE

    Maria Inês Simões; Isabel Marcão; Mário Toscano; Luís Borges

    2018-01-01

    Hidradenocarcinoma is a rare neoplasm of the eccrine cells of the sweat glands, usually asymptomatic with slow growing and higher incidence between 50 and 80 years, occurring in both sexes and preferentially located in the palmar, plantar, frontal, axillary and nuchal regions. It has an aggressive behavior, with high rate of local recurrence and distance metastasis, associated with a poor prognosis. We present a case of hidradenocarcinoma of the scrotum manifested by lymph node metastasis thr...

  14. Comparison of four staging systems of lymph node metastasis in gastric cancer.

    Science.gov (United States)

    Zhang, Ming; Zhu, Guanyu; Ma, Yan; Xue, Yingwei

    2009-11-01

    The classification of lymph node metastasis in patients with gastric cancer is still controversial. Our aim was to evaluate the relative merits of four staging systems of lymph node metastasis. In our study, the nodal status was classified according to the 5th edition of the tumor node metastasis (TNM) system, the Japanese Classification of Gastric Carcinoma (JCGC), the ratio of metastatic lymph nodes, and the size of the largest metastatic lymph node. Each staging system was scored as good (+2), fair (+1), or poor (0) with respect to the theoretical value (extent of the anatomical lymphatic tumor spread), convenience (simplicity), surgical applicability (extent of lymph node dissection), and prognostic value (ability to predict survival rate). In the multivariate analysis including the four staging systems and other potential prognostic factors, stepwise Cox regression revealed that the ratio of metastatic lymph nodes was the most independent prognostic factor. The TNM, ratio, and size systems were convenient because they had no consideration for the location of the tumor and lymph node. Although the JCGC system had advantages in theoretical value and surgical application, it was most optional due to the complexity of the system. Although all different staging systems are comparable, the metastatic lymph node ratio system is convenient, reproducible, and has the highest ability to predict survival.

  15. Morphological analysis of lymph nodes in Odontocetes from north and northeast coast of Brazil.

    Science.gov (United States)

    De Oliveira e Silva, Fernanda Menezes; Guimarães, Juliana Plácido; Vergara-Parente, Jociery Einhardt; Carvalho, Vitor Luz; De Meirelles, Ana Carolina Oliveira; Marmontel, Miriam; Ferrão, Juliana Shimara Pires; Miglino, Maria Angelica

    2014-05-01

    The morphology and location of lymph nodes from seven species of Odontocetes, of both sexes and different age groups, were described. All animals were derived from stranding events along the North and Northeastern coasts of Brazil. After the identification of lymph nodes in situ, tissue samples were analyzed for light and electron microscopy. Vascular volume density (VVD) and vascular length density (VLD) were evaluated in the mesenteric lymph nodes. Lymph nodes occurred as solitary nodules or in groups, varying in shape and size. In addition to using the nomenclature recommended by Nomina Anatomica Veterinaria, new nomenclatures were suggested based on the lymph nodes topography. Lymph nodes were covered by a highly vascularized and innervated capsule of dense connective tissue, below which muscle fibers were observed, inconsistently, in all studied species. There was no difference in VLD among different age groups. However, VVD was higher in adults. Lymph nodes parenchyma was divided into an outer cortex, containing lymph nodules and germinal centers; a paracortical region, transition zone with dense lymphoid tissue; and an inner medulla, composed of small irregular cords of lymphatic tissue, blood vessels, and diffuse lymphoid tissue. Abundant collagen fibers were observed around arteries and arterioles. Germinal centers were more evident and developed in calves and young animals, being more discrete and sparse in adults. The morphology of lymph nodes in Odontocetes was typical of that observed in other terrestrial mammals. However, new groups of lymph nodes were described for seven species occurring in the Brazilian coast. Copyright © 2014 Wiley Periodicals, Inc.

  16. Mediastinal lymph node enlargement on CT scans in idiopathic pulmonary fibrosis

    International Nuclear Information System (INIS)

    Ahn, Joong Mo; Im, Jung Gi; Yu, Kyu In; Kim, Hyeong Seog; Kim, Dae Young; Yu, Pil Mun

    1992-01-01

    The increase in size of lymph node on CT scan is the single most important finding of lymphadenopathy. The purpose of this study was to evaluate the size of mediastinal lymph nodes in patients with idiopathic pulmonary fibrosis with no evidence of malignancy or current infection. CT scans of 70 patients (16 with conventional CT and 54 with high-resolution CT) were assessed for lymph node size and location. The duration of symptoms, and the extent and pattern of the parenchymal lung disease on CT scans were correlated with lymph node enlargement. In 54 of 70 patients, more than one lymph nodes were large than 1-1.5 cm. The prevalence of node enlargement increased significant with a longer duration of symptom (p=0.001), large extent of the disease (p=0.043), and with a greater proportion of honeycomb pattern (p=0.033). Right paratracheal, subcarinal, right tracheobronchial, and paraesophageal nodes were the most common sites of node enlargement. In conclusion, mediastinal lymph node enlargement is common in patients with idiopathic pulmonary fibrosis and is more frequently seen in patients with a longer duration of clinical symptoms, greater extent of the disease, and with a larger proportion of honeycomb pattern

  17. Mediastinal lymph node enlargement on CT scans in idiopathic pulmonary fibrosis

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Joong Mo; Im, Jung Gi; Yu, Kyu In; Kim, Hyeong Seog [Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Dae Young [Chung Buk National University College of Medicine, Chungju (Korea, Republic of); Yu, Pil Mun [Dankuk University College of Medicine, Seoul (Korea, Republic of)

    1992-09-15

    The increase in size of lymph node on CT scan is the single most important finding of lymphadenopathy. The purpose of this study was to evaluate the size of mediastinal lymph nodes in patients with idiopathic pulmonary fibrosis with no evidence of malignancy or current infection. CT scans of 70 patients (16 with conventional CT and 54 with high-resolution CT) were assessed for lymph node size and location. The duration of symptoms, and the extent and pattern of the parenchymal lung disease on CT scans were correlated with lymph node enlargement. In 54 of 70 patients, more than one lymph nodes were large than 1-1.5 cm. The prevalence of node enlargement increased significant with a longer duration of symptom (p=0.001), large extent of the disease (p=0.043), and with a greater proportion of honeycomb pattern (p=0.033). Right paratracheal, subcarinal, right tracheobronchial, and paraesophageal nodes were the most common sites of node enlargement. In conclusion, mediastinal lymph node enlargement is common in patients with idiopathic pulmonary fibrosis and is more frequently seen in patients with a longer duration of clinical symptoms, greater extent of the disease, and with a larger proportion of honeycomb pattern.

  18. Targeted Delivery of Immunomodulators to Lymph Nodes

    Directory of Open Access Journals (Sweden)

    Jamil Azzi

    2016-05-01

    Full Text Available Active-targeted delivery to lymph nodes represents a major advance toward more effective treatment of immune-mediated disease. The MECA79 antibody recognizes peripheral node addressin molecules expressed by high endothelial venules of lymph nodes. By mimicking lymphocyte trafficking to the lymph nodes, we have engineered MECA79-coated microparticles containing an immunosuppressive medication, tacrolimus. Following intravenous administration, MECA79-bearing particles showed marked accumulation in the draining lymph nodes of transplanted animals. Using an allograft heart transplant model, we show that targeted lymph node delivery of microparticles containing tacrolimus can prolong heart allograft survival with negligible changes in tacrolimus serum level. Using MECA79 conjugation, we have demonstrated targeted delivery of tacrolimus to the lymph nodes following systemic administration, with the capacity for immune modulation in vivo.

  19. Sentinel node biopsy before neoadjuvant chemotherapy spares breast cancer patients axillary lymph node dissection.

    Science.gov (United States)

    van Rijk, Maartje C; Nieweg, Omgo E; Rutgers, Emiel J T; Oldenburg, Hester S A; Olmos, Renato Valdés; Hoefnagel, Cornelis A; Kroon, Bin B R

    2006-04-01

    Neoadjuvant chemotherapy in breast cancer patients is a valuable method to determine the efficacy of chemotherapy and potentially downsize the primary tumor, which facilitates breast-conserving therapy. In 18 studies published about sentinel node biopsy after neoadjuvant chemotherapy, the sentinel node was identified in on average 89%, and the false-negative rate was on average 10%. Because of these mediocre results, no author dares to omit axillary clearance just yet. In our institute, sentinel lymph node biopsy is performed before neoadjuvant chemotherapy. The aim of this study was to evaluate our experience with this approach. Sentinel node biopsy was performed before neoadjuvant chemotherapy in 25 T2N0 patients by using lymphoscintigraphy, a gamma ray detection probe, and patent blue dye. Axillary lymph node dissection was performed after chemotherapy if the sentinel node contained metastases. Ten patients had a tumor-positive axillary sentinel node, and one patient had an involved lateral intramammary node. Four patients had additional involved nodes in the completion lymph node dissection specimen. The other 14 patients (56%) had a tumor-negative sentinel node and did not undergo axillary lymph node dissection. No recurrences have been observed after a median follow-up of 18 months. Fourteen (56%) of the 25 patients were spared axillary lymph node dissection when the sentinel node was found to be disease free. Performing sentinel node biopsy before neoadjuvant chemotherapy seems successful and reliable in patients with T2N0 breast cancer.

  20. Node-pair reliability of network systems with small distances between adjacent nodes

    International Nuclear Information System (INIS)

    Malinowski, Jacek

    2007-01-01

    A new method for computing the node-pair reliability of network systems modeled by random graphs with nodes arranged in sequence is presented. It is based on a recursive algorithm using the 'sliding window' technique, the window being composed of several consecutive nodes. In a single step, the connectivity probabilities for all nodes included in the window are found. Subsequently, the window is moved one node forward. This process is repeated until, in the last step, the window reaches the terminal node. The connectivity probabilities found at that point are used to compute the node-pair reliability of the network system considered. The algorithm is designed especially for graphs with small distances between adjacent nodes, where the distance between two nodes is defined as the absolute value of the difference between the nodes' numbers. The maximal distance between any two adjacent nodes is denoted by Γ(G), where G symbolizes a random graph. If Γ(G)=2 then the method can be applied for directed as well as undirected graphs whose nodes and edges are subject to failure. This is important in view of the fact that many algorithms computing network reliability are designed for graphs with failure-prone edges and reliable nodes. If Γ(G)=3 then the method's applicability is limited to undirected graphs with reliable nodes. The main asset of the presented algorithms is their low numerical complexity-O(n), where n denotes the number of nodes

  1. Fluorescence guided lymph node biopsy in large animals using direct image projection device

    Science.gov (United States)

    Ringhausen, Elizabeth; Wang, Tylon; Pitts, Jonathan; Akers, Walter J.

    2016-03-01

    The use of fluorescence imaging for aiding oncologic surgery is a fast growing field in biomedical imaging, revolutionizing open and minimally invasive surgery practices. We have designed, constructed, and tested a system for fluorescence image acquisition and direct display on the surgical field for fluorescence guided surgery. The system uses a near-infrared sensitive CMOS camera for image acquisition, a near-infra LED light source for excitation, and DLP digital projector for projection of fluorescence image data onto the operating field in real time. Instrument control was implemented in Matlab for image capture, processing of acquired data and alignment of image parameters with the projected pattern. Accuracy of alignment was evaluated statistically to demonstrate sensitivity to small objects and alignment throughout the imaging field. After verification of accurate alignment, feasibility for clinical application was demonstrated in large animal models of sentinel lymph node biopsy. Indocyanine green was injected subcutaneously in Yorkshire pigs at various locations to model sentinel lymph node biopsy in gynecologic cancers, head and neck cancer, and melanoma. Fluorescence was detected by the camera system during operations and projected onto the imaging field, accurately identifying tissues containing the fluorescent tracer at up to 15 frames per second. Fluorescence information was projected as binary green regions after thresholding and denoising raw intensity data. Promising results with this initial clinical scale prototype provided encouraging results for the feasibility of optical projection of acquired luminescence during open oncologic surgeries.

  2. Lymphoscintigraphic diagnosis of the lymph node metastasis of esophageal cancer

    International Nuclear Information System (INIS)

    Terui, Shoji; Kawai, Hideo; Hirashima, Toshio; Yamaguchi, Hajime; Kato, Hoichi; Iizuka, Norifumi

    1985-01-01

    Lymphoscintigraphy with 99m Tc-labeled rhenium sulfur colloid was performed preoperatively in 30 patients with esopohageal cancer. It showed hot nodes in a total of 267 lymph nodes, 176 mediastinal nodes and 91 celiac artery nodes. Of these 267 nodes, 47 (18 %) were found to have metastasis, including 34 (19 %) mediastinal nodes and 13 (14 %) celiac artery nodes. On the other hand, the number of non-visualized lymph nodes (cold nodes) was 542. Of them, 78 (14 %) had metastasis; 46 (15 %) were mediastinal nodes and 32 (14 %) were celiac artery nodes. (Namekawa, K.)

  3. An Integrated Hybrid Energy Harvester for Autonomous Wireless Sensor Network Nodes

    Directory of Open Access Journals (Sweden)

    Mukter Zaman

    2014-01-01

    Full Text Available Profiling environmental parameter using a large number of spatially distributed wireless sensor network (WSN NODEs is an extensive illustration of advanced modern technologies, but high power requirement for WSN NODEs limits the widespread deployment of these technologies. Currently, WSN NODEs are extensively powered up using batteries, but the battery has limitation of lifetime, power density, and environmental concerns. To overcome this issue, energy harvester (EH is developed and presented in this paper. Solar-based EH has been identified as the most viable source of energy to be harvested for autonomous WSN NODEs. Besides, a novel chemical-based EH is reported as the potential secondary source for harvesting energy because of its uninterrupted availability. By integrating both solar-based EH and chemical-based EH, a hybrid energy harvester (HEH is developed to power up WSN NODEs. Experimental results from the real-time deployment shows that, besides supporting the daily operation of WSN NODE and Router, the developed HEH is capable of producing a surplus of 971 mA·hr equivalent energy to be stored inside the storage for NODE and 528.24 mA·hr equivalent energy for Router, which is significantly enough for perpetual operation of autonomous WSN NODEs used in environmental parameter profiling.

  4. Application node system image manager subsystem within a distributed function laboratory computer system

    International Nuclear Information System (INIS)

    Stubblefield, F.W.; Beck, R.D.

    1978-10-01

    A computer system to control and acquire data from one x-ray diffraction, five neutron scattering, and four neutron diffraction experiments located at the Brookhaven National Laboratory High Flux Beam Reactor has operated in a routine manner for over three years. The computer system is configured as a network of computer processors with the processor interconnections assuming a star-like structure. At the points of the star are the ten experiment control-data acquisition computers, referred to as application nodes. At the center of the star is a shared service node which supplies a set of shared services utilized by all of the application nodes. A program development node occupies one additional point of the star. The design and implementation of a network subsystem to support development and execution of operating systems for the application nodes is described. 6 figures, 1 table

  5. Autonomous solutions for powering wireless sensor nodes in rivers

    Science.gov (United States)

    Kamenar, E.; Maćešić, S.; Gregov, G.; Blažević, D.; Zelenika, S.; Marković, K.; Glažar, V.

    2015-05-01

    There is an evident need for monitoring pollutants and/or other conditions in river flows via wireless sensor networks. In a typical wireless sensor network topography, a series of sensor nodes is to be deployed in the environment, all wirelessly connected to each other and/or their gateways. Each sensor node is composed of active electronic devices that have to be constantly powered. In general, batteries can be used for this purpose, but problems may occur when they have to be replaced. In the case of large networks, when sensor nodes can be placed in hardly accessible locations, energy harvesting can thus be a viable powering solution. The possibility to use three different small-scale river flow energy harvesting principles is hence thoroughly studied in this work: a miniaturized underwater turbine, a so-called `piezoelectric eel' and a hybrid turbine solution coupled with a rigid piezoelectric beam. The first two concepts are then validated experimentally in laboratory as well as in real river conditions. The concept of the miniaturised hydro-generator is finally embedded into the actual wireless sensor node system and its functionality is confirmed.

  6. Retroperitoneal unicentric Castleman's disease (giant lymph node hyperplasia: case report

    Directory of Open Access Journals (Sweden)

    Jaques Waisberg

    Full Text Available CONTEXT AND OBJECTIVE: Castleman's disease, or giant lymph node hyperplasia, is a rare disorder of the lymphoid tissue that causes lymph node enlargement. It is considered benign in its localized form, but aggressive in the multicentric type. The definitive diagnosis is based on postoperative pathological findings. The aim here was to describe a case of retroperitoneal unicentric Castleman's disease in the retroperitoneum. CASE REPORT: A 61-year old white male with weight loss and listlessness presented with moderate arterial hypertension and leukopenia. Abdominal tomography revealed a 5 x 4 x 5 cm oval mass of low attenuation, with inner calcification and intense enhancement on intravenous contrast, located in the retroperitoneal region, between the left kidney and the aorta, at the renal hilus. Exploratory laparotomy revealed a non-pulsatile solid oval mass situated in the retroperitoneum, adjacent to the left renal hilus. The retroperitoneal lesion was removed in its entirety. Examination of frozen samples revealed benign lymph node tissue and histopathological examination of the surgical sample revealed hyaline-vascular giant lymph node hyperplasia (Castleman's disease. The patient was discharged on the 12th day without significant events. Two months after the operation, the patient was readmitted with severe cardiac insufficiency, acute renal failure and bronchopneumonia, which progressed to acute respiratory insufficiency, sepsis and death.

  7. Radiation Protection Considerations about gamma probe-guided intraoperative sentinel lymph node surgery

    International Nuclear Information System (INIS)

    Rodriguez, C.; Jimenez-Hoyuela Garcia, J. L.; Rebollo Aguirre, J. M.; Custodio, A.

    2002-01-01

    The sentinel node concept is based on the sequential dissemination hypothesis. According to it, there's a lymph node (named sentinel node) which is the first receiving cancer cells metastasizing from a primary tumor. Further, others nodes sequentially located might be affected. Surgical performance for several types of cancer includes the complete removal of the tumor and a complete local lymph node dissection (LND). so removing and analyzing the sentinel node may avoid the complete LND. To locate the sentinel node, it's usual the local administration (intradermal injection) of a radiopharmaceutical Tc-99, sulfur colloid (activity about 1 mCi( several hours prior to surgery, and using an intraoperative gamma probe very sensitive to the gamma radiation. Although the activity is injected by the Nuclear Medicine staff, and be exposed to the gamma radiation. In this study we estimated maximum possible doses that would be received by personnel (surgical staff during surgery and pathologists during lumpectomy of the sentinel node). For the surgical staff, to avoid dose errors due to the very low residual activities and not to interfere with the personnel in the surgery room, we estimated doses by taking into account only the physical decay of Tc99m injected. for the pathologists, we estimated the residual activity in the sentinel node with the gamma probe. The highest effective dose rate found was to the surgeon (o,44 μSv/h, respectively. so a surgeon could perform 407 hours/yr, and a pathologist 1717 hours/yr, dedicated exclusively to sentinel node biopsy, before being classified as professionally exposed to radiation, and 4070 and 17170 hours per year, respectively, to surpass the annual limits (national regulations of the European Communities). In short, radiation doses to clinical staff involved in the technique are low, and in normal conditions, by establishing appropriate procedures (precautions during surgery, during manipulation surgical specimen...) control

  8. Development of GaN-based micro chemical sensor nodes

    Science.gov (United States)

    Son, Kyung-ah; Prokopuk, Nicholas; George, Thomas; Moon, Jeong S.

    2005-01-01

    Sensors based on III-N technology are gaining significant interest due to their potential for monolithic integration of RF transceivers and light sources and the capability of high temperature operations. We are developing a GaN-based micro chemical sensor node for remote detection of chemical toxins, and present electrical responses of AlGaN/GaN HEMT (High Electron Mobility Transistor) sensors to chemical toxins as well as other common gases.

  9. Development of GaN-based microchemical sensor nodes

    Science.gov (United States)

    Prokopuk, Nicholas; Son, Kyung-Ah; George, Thomas; Moon, Jeong S.

    2005-01-01

    Sensors based III-N technology are gaining significant interest due to their potential for monolithic integration of RF transceivers and light sources and the capability of high temperature operations. We are developing a GaN-based micro chemical sensor node for remote detection of chemical toxins, and present electrical responses of AlGaN/GaN HEMT (High Electron Mobility Transistor) sensors to chemical toxins as well as other common gases.

  10. The hidden sentinel node in breast cancer

    International Nuclear Information System (INIS)

    Tanis, P.J.; Sandick, J.W. van; Nieweg, O.E.; Rutgers, E.J.T.; Kroon, B.B.R.; Valdes Olmos, R.A.; Hoefnagel, C.A.

    2002-01-01

    The purpose of this study was to analyse the occurrence of non-visualisation during preoperative lymphoscintigraphy for sentinel node identification in breast cancer. Preoperative lymphoscintigraphy was performed in 495 clinically node-negative breast cancer patients (501 sentinel node procedures) after injection of technetium-99m nanocolloid. Anterior and prone lateral (hanging breast) planar images were obtained a few minutes and 4 h after injection. The sentinel node was intraoperatively identified with the aid of patent blue dye and a gamma-ray detection probe. A sentinel node was visualised on the 4-h images in 449 of 501 procedures (90%). This visualisation rate improved from 76% to 94% during the study period. Delayed imaging (5-23 h) in 19 patients whose sentinel nodes failed to show, resulted in visualisation in four of them. A repeat injection of radiocolloid in 11 patients revealed a sentinel node in six. In the end, the visualisation rate was 92%. The sentinel node was surgically retrieved in 24 of the remaining 42 patients with non-visualisation (57%). Sentinel nodes that were visualised were tumour-positive in 38% and non-visualised sentinel nodes were involved in 50% (χ 2 , P=0.17). In a multivariate regression analysis, scintigraphic non-visualisation was independently associated with increased patient age (P<0.001), decreased tracer dose (P<0.001) and increased number of tumour-positive lymph nodes (P=0.013). The use of a sufficient amount of radioactivity (at least 100 MBq) is recommended for lymphatic mapping in breast cancer, especially in elderly women. Delayed imaging and re-injection of the radioactive tracer increase the visualisation rate. The non-visualised sentinel node can be identified intraoperatively in more than half of the patients. (orig.)

  11. The hidden sentinel node in breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Tanis, P.J.; Sandick, J.W. van; Nieweg, O.E.; Rutgers, E.J.T.; Kroon, B.B.R. [Department of Surgery, Netherlands Cancer Institute, Amsterdam (Netherlands); Valdes Olmos, R.A.; Hoefnagel, C.A. [Department of Nuclear Medicine, Netherlands Cancer Institute, Amsterdam (Netherlands)

    2002-03-01

    The purpose of this study was to analyse the occurrence of non-visualisation during preoperative lymphoscintigraphy for sentinel node identification in breast cancer. Preoperative lymphoscintigraphy was performed in 495 clinically node-negative breast cancer patients (501 sentinel node procedures) after injection of technetium-99m nanocolloid. Anterior and prone lateral (hanging breast) planar images were obtained a few minutes and 4 h after injection. The sentinel node was intraoperatively identified with the aid of patent blue dye and a gamma-ray detection probe. A sentinel node was visualised on the 4-h images in 449 of 501 procedures (90%). This visualisation rate improved from 76% to 94% during the study period. Delayed imaging (5-23 h) in 19 patients whose sentinel nodes failed to show, resulted in visualisation in four of them. A repeat injection of radiocolloid in 11 patients revealed a sentinel node in six. In the end, the visualisation rate was 92%. The sentinel node was surgically retrieved in 24 of the remaining 42 patients with non-visualisation (57%). Sentinel nodes that were visualised were tumour-positive in 38% and non-visualised sentinel nodes were involved in 50% ({chi}{sup 2}, P=0.17). In a multivariate regression analysis, scintigraphic non-visualisation was independently associated with increased patient age (P<0.001), decreased tracer dose (P<0.001) and increased number of tumour-positive lymph nodes (P=0.013). The use of a sufficient amount of radioactivity (at least 100 MBq) is recommended for lymphatic mapping in breast cancer, especially in elderly women. Delayed imaging and re-injection of the radioactive tracer increase the visualisation rate. The non-visualised sentinel node can be identified intraoperatively in more than half of the patients. (orig.)

  12. Gammascintigraphy of metastases of the lymph nodes

    International Nuclear Information System (INIS)

    Mechev, D.S.; Shishkina, V.V.

    1985-01-01

    It was indicated that according to the degree of informative value all the methods used in this study can be listed as follows: the method of combined use of positive and negative scintigraphy, the method of positive scintigraphy with Ga 67 -citrate (the tymph nodes above the diagram) and Tc 99 -pertechnate (the lymph nodes below the diaphragm), the method of indirect radionuclide lymphography with colloids. The main indices of radionuclide methods in the diagnosis of the lymph node metastatic involvement are presented

  13. Occult Pelvic Lymph Node Involvement in Bladder Cancer: Implications for Definitive Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Goldsmith, Benjamin; Baumann, Brian C.; He, Jiwei; Tucker, Kai; Bekelman, Justin; Deville, Curtiland; Vapiwala, Neha [Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania (United States); Vaughn, David; Keefe, Stephen M. [Department of Medical Oncology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania (United States); Guzzo, Thomas; Malkowicz, S. Bruce [Department of Urology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania (United States); Christodouleas, John P., E-mail: christojo@uphs.upenn.edu [Department of Radiation Oncology, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania (United States)

    2014-03-01

    Purpose: To inform radiation treatment planning for clinically staged, node-negative bladder cancer patients by identifying clinical factors associated with the presence and location of occult pathologic pelvic lymph nodes. Methods and Materials: The records of patients with clinically staged T1-T4N0 urothelial carcinoma of the bladder undergoing radical cystectomy and pelvic lymphadenectomy at a single institution were reviewed. Logistic regression was used to evaluate associations between preoperative clinical variables and occult pathologic pelvic or common iliac lymph nodes. Percentages of patient with involved lymph node regions entirely encompassed within whole bladder (perivesicular nodal region), small pelvic (perivesicular, obturator, internal iliac, and external iliac nodal regions), and extended pelvic clinical target volume (CTV) (small pelvic CTV plus common iliac regions) were calculated. Results: Among 315 eligible patients, 81 (26%) were found to have involved pelvic lymph nodes at the time of surgery, with 38 (12%) having involved common iliac lymph nodes. Risk of occult pathologically involved lymph nodes did not vary with clinical T stage. On multivariate analysis, the presence of lymphovascular invasion (LVI) on preoperative biopsy was significantly associated with occult pelvic nodal involvement (odds ratio 3.740, 95% confidence interval 1.865-7.499, P<.001) and marginally associated with occult common iliac nodal involvement (odds ratio 2.307, 95% confidence interval 0.978-5.441, P=.056). The percentages of patients with involved lymph node regions entirely encompassed by whole bladder, small pelvic, and extended pelvic CTVs varied with clinical risk factors, ranging from 85.4%, 95.1%, and 100% in non-muscle-invasive patients to 44.7%, 71.1%, and 94.8% in patients with muscle-invasive disease and biopsy LVI. Conclusions: Occult pelvic lymph node rates are substantial for all clinical subgroups, especially patients with LVI on biopsy. Extended

  14. Dynamic Roles and Locations of Manufacturing

    DEFF Research Database (Denmark)

    Slepniov, Dmitrij; Wæhrens, Brian Vejrum; Johansen, John

    2014-01-01

    Purpose – The principal objective of this paper is to relate functional nodes of production and innovation in global operations networks. The authors aim to capture the implications of changing strategic roles and locations of manufacturing for innovation capabilities. Design...... companies presented in this paper, the authors find that although the potential benefits of global dispersion of manufacturing are vast, the realisation of these potentials depends on how successful companies are with linking the new strategic roles and locations of manufacturing with innovation...... of global dispersion of operations. The findings assist global companies in organising cross-functional coordination and interrelated functional nodes of production and innovation in global operations networks. Originality/value – Not only routine transactional tasks but also more knowledge...

  15. The complex network reliability and influential nodes

    Science.gov (United States)

    Li, Kai; He, Yongfeng

    2017-08-01

    In order to study the complex network node important degree and reliability, considering semi-local centrality, betweenness centrality and PageRank algorithm, through the simulation method to gradually remove nodes and recalculate the importance in the random network, small world network and scale-free network. Study the relationship between the largest connected component and node removed proportion, the research results show that betweenness centrality and PageRank algorithm based on the global information network are more effective for evaluating the importance of nodes, and the reliability of the network is related to the network topology.

  16. Tunable locally-optimal geographical forwarding in wireless sensor networks with sleep-wake cycling nodes

    OpenAIRE

    Naveen, K. P.; Kumar, A.

    2009-01-01

    We consider a wireless sensor network whose main function is to detect certain infrequent alarm events, and to forward alarm packets to a base station, using geographical forwarding. The nodes know their locations, and they sleep-wake cycle, waking up periodically but not synchronously. In this situation, when a node has a packet to forward to the sink, there is a trade-off between how long this node waits for a suitable neighbor to wake up and the progress the packet makes towards the sink o...

  17. Efficient and Adaptive Node Selection for Target Tracking in Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Juan Feng

    2016-01-01

    Full Text Available In target tracking wireless sensor network, choosing the proper working nodes can not only minimize the number of active nodes, but also satisfy the tracking reliability requirement. However, most existing works focus on selecting sensor nodes which are the nearest to the target for tracking missions and they did not consider the correlation of the location of the sensor nodes so that these approaches can not meet all the goals of the network. This work proposes an efficient and adaptive node selection approach for tracking a target in a distributed wireless sensor network. The proposed approach combines the distance-based node selection strategy and particle filter prediction considering the spatial correlation of the different sensing nodes. Moreover, a joint distance weighted measurement is proposed to estimate the information utility of sensing nodes. Experimental results show that EANS outperformed the state-of-the-art approaches by reducing the energy cost and computational complexity as well as guaranteeing the tracking accuracy.

  18. Location constrained resource interconnection

    International Nuclear Information System (INIS)

    Hawkins, D.

    2008-01-01

    This presentation discussed issues related to wind integration from the perspective of the California Independent System Operator (ISO). Issues related to transmission, reliability, and forecasting were reviewed. Renewable energy sources currently used by the ISO were listed, and details of a new transmission financing plan designed to address the location constraints of renewable energy sources and provide for new transmission infrastructure was presented. The financing mechanism will be financed by participating transmission owners through revenue requirements. New transmission interconnections will include network facilities and generator tie-lines. Tariff revisions have also been implemented to recover the costs of new facilities and generators. The new transmission project will permit wholesale transmission access to areas where there are significant energy resources that are not transportable. A rate impact cap of 15 per cent will be imposed on transmission owners to mitigate short-term costs to ratepayers. The presentation also outlined energy resource area designation plans, renewable energy forecasts, and new wind technologies. Ramping issues were also discussed. It was concluded that the ISO expects to ensure that 20 per cent of its energy will be derived from renewable energy sources. tabs., figs

  19. Photoacoustic imaging of human lymph nodes with endogenous lipid and hemoglobin contrast

    Science.gov (United States)

    Guggenheim, James A.; Allen, Thomas J.; Plumb, Andrew; Zhang, Edward Z.; Rodriguez-Justo, Manuel; Punwani, Shonit; Beard, Paul C.

    2015-05-01

    Lymph nodes play a central role in metastatic cancer spread and are a key clinical assessment target. Abnormal node vascularization, morphology, and size may be indicative of disease but can be difficult to visualize with sufficient accuracy using existing clinical imaging modalities. To explore the potential utility of photoacoustic imaging for the assessment of lymph nodes, images of ex vivo samples were obtained at multiple wavelengths using a high-resolution three-dimensional photoacoustic scanner. These images showed that hemoglobin based contrast reveals nodal vasculature and lipid-based contrast reveals the exterior node size, shape, and boundary integrity. These two sources of complementary contrast may allow indirect observation of cancer, suggesting a future role for photoacoustic imaging as a tool for the clinical assessment of lymph nodes.

  20. Sentinel node concept in breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kiricuta, I.C. [St. Vincenz-Hospital, Limburg (Germany). Inst. for Radiation Oncology

    2000-07-01

    Background/purpose: It seems that there exists a specific lymph node center called sentinel node (SN) which appears to be the primary site of metastases. The sentinel node concept (SNC) is fundamentally based on the orderly progression of tumor cells within the lymphatic system. It is the most important new concept in surgical and radiation oncology. The purpose is to present the biological significance, the diagnostic and clinical basis of the sentinel node concept in breast cancer patients. Material and methods: Lymphoscintigraphy and gamma probe biopsy is necessary to show predictable lymph flow to the regional sentinel node, to multiple sentinel nodes or unpredictable lymph flow to extra-regional sentinel nodes and for performing sentinel node procedure. The standard protocol for the evaluation of the sentinel node metastases consists of extensive histopathological investigation including step Hematoxylin and Eosin (H and E) stained sections and immunohistochemistry. Results: A high rate of success of the identification of the sentinel node for breast cancer was reported. The presence or absence of metastasis in this node is a very accurate predictor of overall nodal status. The temptation to examine the sentinel node with the greatest possible degree of accuracy highlights one of the major problems related to sentinel node biopsy. The success of the sentinel node procedure depends primarily on the adequate functional capacity necessary for sufficient uptake to ensure the accurate identification. In negative sentinel-node patients a complete axillary lymph node dissection is avoidable. In sentinel-node positive patients and clinically negative patients a postoperative radiotherapy would permit an adequate tumor control. The last 2-procedures permit a low morbidity. In the actual TNM classification it was recently introduced a definition of a 'pN0' patient based on sentinel node biopsy. New target volumes are defined for adjuvant radiotherapy or

  1. Sentinel Node Biopsy Alone versus Completion Axillary Node Dissection in Node Positive Breast Cancer: Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Rachna Ram

    2014-01-01

    Full Text Available Introduction. There has been recent interest in validity of completion axillary node dissection after a positive sentinel node. This systematic review aims to ascertain if sentinel lymph node dissection alone was noninferior to axillary lymph node dissection for breast cancer patients who have a positive sentinel node. Method. A systematic review of the electronic databases Embase, MEDLINE, and Cochrane Register of Controlled Trials was carried out. Only randomised trials that had patients with positive sentinel node as the study sample were included in the meta-analysis using the reported hazard ratios with a fixed effect model. Results. Three randomised controlled trials and five retrospective studies were identified. The pooled effect for overall survival was HR 0.94, 95% CI [0.79, 1.19], and for disease free survival was HR 0.83, 95% CI [0.60, 1.14]. The reported rates for locoregional recurrence were similar in both groups. The surgical morbidity was found to be significantly more in patients who had underwent axillary dissection. Conclusion. Amongst patients with micrometastasis in the sentinel node, no further axillary dissection is necessary. For patients with macrometastasis in the sentinel node, it is reasonable to consider omitting axillary dissection to avoid the morbidity of the procedure.

  2. Sentinel Lymph Node Biopsy (SLNB) for Breast Cancer (BC) - Validation Protocol of the Technique

    International Nuclear Information System (INIS)

    Blidaru, A.; Bordea, C.I.; Condrea, Ileana; Albert, Paul

    2006-01-01

    Full text: The sentinel ganglion concept originates in the assumption according to which the primary tumor drains into a specific ganglionar area and then runs through the lymphatic nodes in an orderly, sequential mode. When neoplastic dissemination along the lymphatic pathway occurs, there is an initial invasion of a specific lymph node (rarely more than one) located on the drainage route. That firstly lymph node has been identified as the sentinel node, which mirrors the regional ganglionar status. In order to establish the indication for lymphadenectomy and avoid the situations in which such a surgical procedure would be of no use (N-), the only correct method consists in the identification and biopsy of the sentinel node. Radioactive tracing and/or use of vital staining enable the identification of the regional ganglionar group towards which the primary lesion is draining. The technique of sentinel lymph node identification and biopsy by means of radioactive tracing includes: - pre-surgical lymphoscintigraphy, - identification of the sentinel lymph node and its excisional biopsy, - intra-operative histopathological examination and immunohistochemical stains of the sentinel lymph node. Regional lymphadenectomy serves two major purposes: - diagnosis (axillary lymph node invasion represents an important prognostic factor) and therapeutic (to ensure local control of the disease). Regional lymph node invasion in breast cancer is directly related to the primary tumour size. In the less advanced stages (T1), as there is rarely invasion of the axillary lymph nodes, lymphadenectomy can be avoided in most cases. The paper presents the refinement of the technique, the validation of the method for the identification and biopsy of the sentinel lymph node in breast cancer using Tc99 and the intra-operative use of NEOPROBE 2000 gamma camera at the 'Prof. Dr. Alexandru Trestioreanu' Oncological Institute in Bucharest. 93 patients with primary breast cancer (T1, T2, N0

  3. Shortening treatment time in robotic radiosurgery using a novel node reduction technique

    Energy Technology Data Exchange (ETDEWEB)

    Water, Steven van de; Hoogeman, Mischa S.; Breedveld, Sebastiaan; Heijmen, Ben J. M. [Department of Radiation Oncology, Erasmus MC-Daniel den Hoed Cancer Center, Groene Hilledijk 301, 3075 EA Rotterdam (Netherlands)

    2011-03-15

    Purpose: The fraction duration of robotic radiosurgery treatments can be reduced by generating more time-efficient treatment plans with a reduced number of node positions, beams, and monitor units (MUs). Node positions are preprogramed locations where the robot can position the focal spot of the x-ray beam. As the time needed for the robot to travel between node positions takes up a large part of the treatment time, the aim of this study was to develop and evaluate a node reduction technique in order to reduce the treatment time per fraction for robotic radiosurgery. Methods: Node reduction was integrated into the inverse planning algorithm, developed in-house for the robotic radiosurgery modality. It involved repeated inverse optimization, each iteration excluding low-contribution node positions from the planning and resampling new candidate beams from the remaining node positions. Node reduction was performed until the exclusion of a single node position caused a constraint violation, after which the shortest treatment plan was selected retrospectively. Treatment plans were generated with and without node reduction for two lung cases of different complexity, one oropharyngeal case and one prostate case. Plan quality was assessed using the number of node positions, beams and MUs, and the estimated treatment time per fraction. All treatment plans had to fulfill all clinical dose constraints. Extra constraints were added to maintain the low-dose conformality and restrict skin doses during node reduction. Results: Node reduction resulted in 12 residual node positions, on average (reduction by 77%), at the cost of an increase in the number of beams and total MUs of 28% and 9%, respectively. Overall fraction durations (excluding patient setup) were shortened by 25% (range of 18%-40%), on average. Dose distributions changed only little and dose in low-dose regions was effectively restricted by the additional constraints. Conclusions: The fraction duration of robotic

  4. Shortening treatment time in robotic radiosurgery using a novel node reduction technique

    International Nuclear Information System (INIS)

    Water, Steven van de; Hoogeman, Mischa S.; Breedveld, Sebastiaan; Heijmen, Ben J. M.

    2011-01-01

    Purpose: The fraction duration of robotic radiosurgery treatments can be reduced by generating more time-efficient treatment plans with a reduced number of node positions, beams, and monitor units (MUs). Node positions are preprogramed locations where the robot can position the focal spot of the x-ray beam. As the time needed for the robot to travel between node positions takes up a large part of the treatment time, the aim of this study was to develop and evaluate a node reduction technique in order to reduce the treatment time per fraction for robotic radiosurgery. Methods: Node reduction was integrated into the inverse planning algorithm, developed in-house for the robotic radiosurgery modality. It involved repeated inverse optimization, each iteration excluding low-contribution node positions from the planning and resampling new candidate beams from the remaining node positions. Node reduction was performed until the exclusion of a single node position caused a constraint violation, after which the shortest treatment plan was selected retrospectively. Treatment plans were generated with and without node reduction for two lung cases of different complexity, one oropharyngeal case and one prostate case. Plan quality was assessed using the number of node positions, beams and MUs, and the estimated treatment time per fraction. All treatment plans had to fulfill all clinical dose constraints. Extra constraints were added to maintain the low-dose conformality and restrict skin doses during node reduction. Results: Node reduction resulted in 12 residual node positions, on average (reduction by 77%), at the cost of an increase in the number of beams and total MUs of 28% and 9%, respectively. Overall fraction durations (excluding patient setup) were shortened by 25% (range of 18%-40%), on average. Dose distributions changed only little and dose in low-dose regions was effectively restricted by the additional constraints. Conclusions: The fraction duration of robotic

  5. Penile Cancer: Contemporary Lymph Node Management.

    Science.gov (United States)

    O'Brien, Jonathan S; Perera, Marlon; Manning, Todd; Bozin, Mike; Cabarkapa, Sonja; Chen, Emily; Lawrentschuk, Nathan

    2017-06-01

    In penile cancer, the optimal diagnostics and management of metastatic lymph nodes are not clear. Advances in minimally invasive staging, including dynamic sentinel lymph node biopsy, have widened the diagnostic repertoire of the urologist. We aimed to provide an objective update of the recent trends in the management of penile squamous cell carcinoma, and inguinal and pelvic lymph node metastases. We systematically reviewed several medical databases, including the Web of Science® (with MEDLINE®), Embase® and Cochrane databases, according to PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analyses) guidelines. The search terms used were penile cancer, lymph node, sentinel node, minimally invasive, surgery and outcomes, alone and in combination. Articles pertaining to the management of lymph nodes in penile cancer were reviewed, including original research, reviews and clinical guidelines published between 1980 and 2016. Accurate and minimally invasive lymph node staging is of the utmost importance in the surgical management of penile squamous cell carcinoma. In patients with clinically node negative disease, a growing body of evidence supports the use of sentinel lymph node biopsies. Dynamic sentinel lymph node biopsy exposes the patient to minimal risk, and results in superior sensitivity and specificity profiles compared to alternate nodal staging techniques. In the presence of locoregional disease, improvements in inguinal or pelvic lymphadenectomy have reduced morbidity and improved oncologic outcomes. A multimodal approach of chemotherapy and surgery has demonstrated a survival benefit for patients with advanced disease. Recent developments in lymph node management have occurred in penile cancer, such as minimally invasive lymph node diagnosis and intervention strategies. These advances have been met with a degree of controversy in the contemporary literature. Current data suggest that dynamic sentinel lymph node biopsy provides excellent

  6. Enhancement characteristics of retroperitoneal lymphomatous lymph nodes

    International Nuclear Information System (INIS)

    Hagtvedt, Trond; Smith, Hans-Joergen; Kolbenstvedt, Alf; Aaloekken, Trond Mogens; Graff, Bjoern Anton; Holte, Harald

    2013-01-01

    Background: Previous studies of CT enhancement of lymphomatous lymph nodes (LLN) of the neck and the mediastinum showed that the LLN had lower enhancement values than normal lymph nodes. Purpose: To elucidate the contrast medium enhancement curves of LLN in the retroperitoneum by comparing the curves of LLN with those of normal lymph nodes, to test whether differences between these curves could be of diagnostic value, and to compare the present enhancement curves of LLN of the retroperitoneum with the curves of LLN of the neck and the mediastinum from previous similar investigations. Material and Methods: Twenty-eight consecutive patients with LLN of the retroperitoneum (three with Hodgkin's lymphoma [HL]) and 21 control patients with sarcomas and thus presumably normal retroperitoneal nodes underwent dynamic CT examinations. The previous, similar investigation of lymph nodes of the neck comprised 28 patients with LLN and the investigation of mediastinal lymph nodes comprised 24 patients with LLN. Results: The enhancement curves of the retroperitoneal LLN had significantly lower attenuation than those of the retroperitoneal control nodes. A combination of peak contrast value and time to peak adjusted to total body weight yielded a diagnostic accuracy which at the best showed a sensitivity of 90.5% with a specificity of 82.6%. The LLN of the retroperitoneum had higher attenuation values than corresponding nodes of the mediastinum but no significant difference was found between LLN of the retroperitoneum and LLN of the neck in previous similar investigations. Conclusion: The comparison of enhancement curves of retroperitoneal LLN with retroperitoneal control nodes showed a marked similarity with and substantiates our previous findings in lymph nodes of the neck and of the mediastinum. The best diagnostic accuracy was achieved by combining the parameters peak contrast value and time to peak and adjusting these values to the body weight. Peak enhancement of the

  7. Sentinel lymph node (Sln) detection in vulvar cancer

    International Nuclear Information System (INIS)

    Grimm, J.; Mende, T.; Lantzsch, T.; Seliger, G.; Koelbl, H.; Buchmann, J.

    2002-01-01

    Full text: The purpose of the study is to verify the feasibility of the sentinel lymph node (SLN) procedure in patients with evidence of vulva cancer. We studied 13 women with early stage (T1/T2) carcinoma of the vulva. One day before surgery a lymphoscintigraphy was done. We injected intradermally an average 76 MBq of 99m Tc-labelled human colloides (Albu-Res(r) in 0.4-0.6 ml NaCI at 4 locations round the tumor regarding the midline. Because of the large particles the colloid was filtered before to obtain the small particle fraction between 200-450 nm. Immediately alter injection a dynamic scintigraphy was performed with 28 images, 1 minute per frame. Additional we made static images, 5 minutes per image, 30 and 120 minutes after injection. The location of the SLN was marked on the skin. The SLN was intraoperatively identified using a hand-held gamma probe. In every case a complete inguino-femoral lymph node dissection was done. In all cases we could show one or more (on average 3) SLN by means of lymphoscintigraphy and in 11/13 cases we could detect SLN by using the gamma probe. Lymph channels were seen in 7/13 dynamic studies. 4/13 patients had lymph node metastasis in the SLN (3/4 cases only the SLN and in 1/4 cases the SLN and one additional lymph node were positive). We did not found any tumor-positive non-sentinel lymph node in case of tumor-negative SLN. The morbidity after operation of patients with vulva cancer is considerable and related to the groin dissection. The selective SLN-biopsy instead of radical groin dissection is feasible to reduce the morbidity without a loss of staging and prognostic factors. This method should be restricted to patients with early stage vulva cancer with clinically uninvolved lymph nodes. Further studies are needed to evaluate the accuracy and clinical validity of this procedure. (author)

  8. Modeling discrete competitive facility location

    CERN Document Server

    Karakitsiou, Athanasia

    2015-01-01

    This book presents an up-to-date review of modeling and optimization approaches for location problems along with a new bi-level programming methodology which captures the effect of competition of both producers and customers on facility location decisions. While many optimization approaches simplify location problems by assuming decision making in isolation, this monograph focuses on models which take into account the competitive environment in which such decisions are made. New insights in modeling, algorithmic and theoretical possibilities are opened by this approach and new applications are possible. Competition on equal term plus competition between market leader and followers are considered in this study, consequently bi-level optimization methodology is emphasized and further developed. This book provides insights regarding modeling complexity and algorithmic approaches to discrete competitive location problems. In traditional location modeling, assignment of customer demands to supply sources are made ...

  9. Seismic and Infrasound Location

    Energy Technology Data Exchange (ETDEWEB)

    Arrowsmith, Stephen J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Begnaud, Michael L. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-03-19

    This presentation includes slides on Signal Propagation Through the Earth/Atmosphere Varies at Different Scales; 3D Seismic Models: RSTT; Ray Coverage (Pn); Source-Specific Station Corrections (SSSCs); RSTT Conclusions; SALSA3D (SAndia LoS Alamos) Global 3D Earth Model for Travel Time; Comparison of IDC SSSCs to RSTT Predictions; SALSA3D; Validation and Model Comparison; DSS Lines in the Siberian Platform; DSS Line CRA-4 Comparison; Travel Time Δak135; Travel Time Prediction Uncertainty; SALSA3D Conclusions; Infrasound Data Processing: An example event; Infrasound Data Processing: An example event; Infrasound Location; How does BISL work?; BISL: Application to the 2013 DPRK Test; and BISL: Ongoing Research.

  10. Automated Construction of Node Software Using Attributes in a Ubiquitous Sensor Network Environment

    Science.gov (United States)

    Lee, Woojin; Kim, Juil; Kang, JangMook

    2010-01-01

    In sensor networks, nodes must often operate in a demanding environment facing restrictions such as restricted computing resources, unreliable wireless communication and power shortages. Such factors make the development of ubiquitous sensor network (USN) applications challenging. To help developers construct a large amount of node software for sensor network applications easily and rapidly, this paper proposes an approach to the automated construction of node software for USN applications using attributes. In the proposed technique, application construction proceeds by first developing a model for the sensor network and then designing node software by setting the values of the predefined attributes. After that, the sensor network model and the design of node software are verified. The final source codes of the node software are automatically generated from the sensor network model. We illustrate the efficiency of the proposed technique by using a gas/light monitoring application through a case study of a Gas and Light Monitoring System based on the Nano-Qplus operating system. We evaluate the technique using a quantitative metric—the memory size of execution code for node software. Using the proposed approach, developers are able to easily construct sensor network applications and rapidly generate a large number of node softwares at a time in a ubiquitous sensor network environment. PMID:22163678

  11. Automated Construction of Node Software Using Attributes in a Ubiquitous Sensor Network Environment

    Directory of Open Access Journals (Sweden)

    JangMook Kang

    2010-09-01

    Full Text Available In sensor networks, nodes must often operate in a demanding environment facing restrictions such as restricted computing resources, unreliable wireless communication and power shortages. Such factors make the development of ubiquitous sensor network (USN applications challenging. To help developers construct a large amount of node software for sensor network applications easily and rapidly, this paper proposes an approach to the automated construction of node software for USN applications using attributes. In the proposed technique, application construction proceeds by first developing a model for the sensor network and then designing node software by setting the values of the predefined attributes. After that, the sensor network model and the design of node software are verified. The final source codes of the node software are automatically generated from the sensor network model. We illustrate the efficiency of the proposed technique by using a gas/light monitoring application through a case study of a Gas and Light Monitoring System based on the Nano-Qplus operating system. We evaluate the technique using a quantitative metric—the memory size of execution code for node software. Using the proposed approach, developers are able to easily construct sensor network applications and rapidly generate a large number of node softwares at a time in a ubiquitous sensor network environment.

  12. Automated construction of node software using attributes in a ubiquitous sensor network environment.

    Science.gov (United States)

    Lee, Woojin; Kim, Juil; Kang, JangMook

    2010-01-01

    In sensor networks, nodes must often operate in a demanding environment facing restrictions such as restricted computing resources, unreliable wireless communication and power shortages. Such factors make the development of ubiquitous sensor network (USN) applications challenging. To help developers construct a large amount of node software for sensor network applications easily and rapidly, this paper proposes an approach to the automated construction of node software for USN applications using attributes. In the proposed technique, application construction proceeds by first developing a model for the sensor network and then designing node software by setting the values of the predefined attributes. After that, the sensor network model and the design of node software are verified. The final source codes of the node software are automatically generated from the sensor network model. We illustrate the efficiency of the proposed technique by using a gas/light monitoring application through a case study of a Gas and Light Monitoring System based on the Nano-Qplus operating system. We evaluate the technique using a quantitative metric-the memory size of execution code for node software. Using the proposed approach, developers are able to easily construct sensor network applications and rapidly generate a large number of node softwares at a time in a ubiquitous sensor network environment.

  13. Localized Lymph Node Light Chain Amyloidosis

    Directory of Open Access Journals (Sweden)

    Binod Dhakal

    2015-01-01

    Full Text Available Immunoglobulin-derived light chain amyloidosis can occasionally be associated with localized disease. We present a patient with localized lymph node light chain amyloidosis without an underlying monoclonal protein or lymphoproliferative disorder and review the literature of lymph node amyloidosis discussing work-up and risk factors for systemic progression.

  14. Sentinel lymph node identification with magnetic nanoparticles

    NARCIS (Netherlands)

    Pouw, Joost Jacob

    2016-01-01

    Most solid malignancies have a tendency to spread through the lymphatic system to locoregional lymph nodes. Presence of metastasis is an important prognostic factor, and is used to determine the optimal treatment of the patient. The sentinel lymph nodes (SLNs) receive direct lymphatic drainage from

  15. Testnodes: a Lightweight node-testing infrastructure

    International Nuclear Information System (INIS)

    Fay, R; Bland, J

    2014-01-01

    A key aspect of ensuring optimum cluster reliability and productivity lies in keeping worker nodes in a healthy state. Testnodes is a lightweight node testing solution developed at Liverpool. While Nagios has been used locally for general monitoring of hosts and services, Testnodes is optimised to answer one question: is there any reason this node should not be accepting jobs? This tight focus enables Testnodes to inspect nodes frequently with minimal impact and provide a comprehensive and easily extended check with each inspection. On the server side, Testnodes, implemented in python, interoperates with the Torque batch server to control the nodes production status. Testnodes remotely and in parallel executes client-side test scripts and processes the return codes and output, adjusting the node's online/offline status accordingly to preserve the integrity of the overall batch system. Testnodes reports via log, email and Nagios, allowing a quick overview of node status to be reviewed and specific node issues to be identified and resolved quickly. This presentation will cover testnodes design and implementation, together with the results of its use in production at Liverpool, and future development plans.

  16. [The related factors of head and neck mocosal melanoma with lymph node metastasis].

    Science.gov (United States)

    Yin, G F; Guo, W; Chen, X H; Huang, Z G

    2017-12-05

    Objective: To investigate the related factors of mucosal melanoma of head and neck with lymph node metastasis for early diagnosis and further treatments. Method: A retrospective analysis of 117 cases of head and neck mucosal malignant melanoma patients which received surgical treatment was performed. Eleven cases of patients with pathologically confirmed lymph node metastasis and 33 cases without lymph node metastasis (1∶3) were randomly selected to analyze. The related factors of lymph node metastasis of head and neck mucosal melanoma patients including age, gender, whether the existence of recurrence, bone invasion, lesion location were analyzed. The single factor and logistic regression analysis were performed, P difference was statistically significant. Result: The lymph node metastasis rate of head and neck mucosal melanoma was 9.40%(11/117), the single factor analysis showed that there were 3 factors to be associated with lymph node metastasis, which was recurrence ( P =0.0000), bone invasion ( P =0.001), primary position ( P =0.007). Recurrence ( P =0.021) was a risk factor for lymph node metastasis according to the Logistic regression analysis, and the impact of bone invasion ( P =0.487) and primary location ( P =0.367) remained to be further explored. Conclusion: The patients of head and neck mucosal melanoma with the presence of recurrent usually accompanied by a further progression of the disease, such as lymph node metastasis, so for recurrent patients should pay special attention to the situation of lymph node and choose the reasonable treatment. Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.

  17. Finding Hidden Location Patterns of Two Competitive Supermarkets in Thailand

    Science.gov (United States)

    Khumsri, Jinattaporn; Fujihara, Akihiro

    There are two famous supermarkets in Thailand: Big C and Lotus. They are the highest competitive supermarkets whose hold the most market share by lots of promotions and also gather all convenience services including banking, restaurant, and others. In recent years, they gradually expand their stores and they take a similar strategy to determine where to locate a store. It is important for them to consider store allocation to obtain new customers efficiently. To consider this, we gather geographical locations of these supermarkets from Twitter using Twitter API. We gathered tweets having these supermarket names and geotags for seven months. To extract hidden location patterns from gathered data, we introduce location motif which is a directed subgraph whose edges are linked to every pair of the shortest-distance opponent node. We investigate every possible configuration of location motif when they have a small number of nodes and find that the configuration increases exponentially. We also visualize location motifs generated from gathered data on the map of Thailand and count the frequency of observed location motifs. As a result, we find that even if the possible location motifs exponentially increase as the number of nodes grows, limited location motifs can be observed. Using location motif, we successfully find an evidence of biased store allocation in reality.

  18. Sentinel lymph node imaging in breast cancer

    International Nuclear Information System (INIS)

    Kim, Byung Tae

    1999-01-01

    Currently, dissection of the axillary or regional lymph nodes is considered the standard staging procedure in breast cancer. However, accumulating evidence is becoming available that the sentinel node concept may provide the same or even better staging information. In the case of melanoma, it is proven that the histological characteristics of the sentinel node reflect the histological characteristics of the distal part of the lymphatic basin. Morbidity can be reduced significantly by the use of sentinel node dissection as several authors have reported successful introduction of this technique into clinical practice. But in breast cancer patients, there are significant differences in practice relating to the technology, such as radiopharmaceuticals, injection sites, volume of injectate, combination with vital blue dye, preoperative lymphoscintigraphy, etc. Valuable reports on these topics appeared in recent journals. This review is a summary of those reports for nuclear physicians interested in sentinel node detection by lymphoscintigraphy in breast cancer patients

  19. A Centralized Detection of Sinkhole Attacks Based on Energy Level of the Nodes on Cluster-Based Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Merve Nilay Aydın

    2017-10-01

    Full Text Available Wireless Sensor Networks is consist of thousands of small and low-cost devices, which communicate over wireless medium. Due to locating in harsh environment and having limited resources, WSN is prone to various attacks. One of the most dangerous attacks threatening WSN is the sinkhole attack. In this paper, sinkhole attack is modelled on a cluster-based WSN, and a centralized detection algorithm based on the remaining energies of the nodes is proposed. The simulations were run for different values of energy thresholds and various numbers of nodes. The performance of the system was investigated over total energy consumption in the system, the number of packets arrived at base station and true detection rate of the sinkhole node(s. The results showed that the proposed method is energy-efficient and detects the malicious nodes with a 100% accuracy for all number of nodes.

  20. A Location-Based Business Information Recommendation Algorithm

    Directory of Open Access Journals (Sweden)

    Shudong Liu

    2015-01-01

    Full Text Available Recently, many researches on information (e.g., POI, ADs recommendation based on location have been done in both research and industry. In this paper, we firstly construct a region-based location graph (RLG, in which region node respectively connects with user node and business information node, and then we propose a location-based recommendation algorithm based on RLG, which can combine with user short-ranged mobility formed by daily activity and long-distance mobility formed by social network ties and sequentially can recommend local business information and long-distance business information to users. Moreover, it can combine user-based collaborative filtering with item-based collaborative filtering, and it can alleviate cold start problem which traditional recommender systems often suffer from. Empirical studies from large-scale real-world data from Yelp demonstrate that our method outperforms other methods on the aspect of recommendation accuracy.

  1. A Location Privacy Aware Friend Locator

    DEFF Research Database (Denmark)

    Siksnys, Laurynas; Thomsen, Jeppe Rishede; Saltenis, Simonas

    2009-01-01

    to trade their location privacy for quality of service, limiting the attractiveness of the services. The challenge is to develop a communication-efficient solution such that (i) it detects proximity between a user and the user’s friends, (ii) any other party is not allowed to infer the location of the user...

  2. The 'Sentinel Node' Concept: More Questions Raised than Answers Provided?

    Science.gov (United States)

    Schlag

    1998-01-01

    The prognosis of malignant disease is essentially determined by the metastatic potential of the primary tumor. In the past, scientific attention was chiefly directed to systemic metastasis. A multitude of biological and molecular tumor markers and mechanisms has been uncovered enabling a better contemporary understanding of the process of hematogenic metastasis. This is in contrast with our knowledge of the mechanisms and pathways of lymphatic tumor spread, which is rather limited. We do know, however, that adequate surgical clearance of the regional lymphatics improves treatment results of many tumors. How far this lymph node dissection is directly therapeutic is a source of controversy. While in some instances, a stage-adjusted survival benefit was demonstrated, this may very well be attributable at least in part to the phenomenon of stage migration (Will Rodgers phenomenon) through better staging. However, it is uncontested that an established diagnosis of regional lymphatic spread is prognostically significant and should influence the indication for additional therapy and eventually for an intensive follow-up. For many tumors, the indication for adjuvant chemotherapy depends on the nodal status. On the other hand, it is equally well known that aggressive lymphatic dissection increases perioperative morbidity and even mortality. Long-term sequellae from regional lymphatic dissection are common and the effect on the local, maybe even the systemic immunological response to the malignant disease, remains unclear. To incur such risk seems especially problematic in those patients without any lymphatic spread at the time of the pathologist's work-up. Thus, there is ongoing debate about the rationale, value, extent, advantage, or disadvantage of regional surgical lymph node dissection or even radiotherapy of the regional lymphatic drainage area for many different tumors. A considerable step forward could be made if there was any diagnostic modality enabling a reliable

  3. Lymph Node Failure Pattern and Treatment Results of Esophageal Cancer Patients Treated with Definitive Radiotherapy

    International Nuclear Information System (INIS)

    Lee, Sun Young; Kwon, Hyoung Cheol; Kim, Jung Soo; Lee, Heui Kwan; Kim, Soo Geon

    2008-01-01

    We evaluated the failure pattern of the celiac axis, gastric lymph node, and treatment outcome in the upper and mid-esophageal region of cancer patients treated by definitive radiotherapy, except when treating the celiac axis and gastric lymph node for treatment volume, retrospectively. Materials and Methods: The study constituted the evaluation 108 patients with locally advanced esophageal cancer receiving radiotherapy or a combination of radiotherapy and chemotherapy at Chonbuk National University Hospital from January 1986 to December 2006. In total, 82 patients treated by planned radiotherapy, except when treating the celiac axis and gastric lymph node for treatment volume, were analysed retrospectively. The study population consisted of 78 men and 2 women (mean age of 63.2 years). In addition, 51 patients received radiotherapy alone, whereas 31 patients received a combination of radiation therapy and chemotherapy. The primary cancer sites were located in the upper portion (17 patients), and mid portion (65 patients), respectively. Further, the patients were in various clinical stages including T1N0-1M0 (7 patients), T2N0-1M0 (18 patients), T3N0-1M0 (44 patients) and T4N0-1M0 (13 patients). The mean follow up period was 15 months. Results: The various treatment outcomes included complete response (48 patients), partial response (31 patients) and no response (3 patients). The failure patterns of the lymph node were comprised of the regional lymph node (23 patients) and the distance lymph node which included celiac axis and gastric lymph node (13 patients). However, metastasis was not observed in the regional and distant lymph node in 10 patients, whereas 36 patients were not evaluated. Furthermore, of the 13 patients who developed celiac axis and gastric lymph node metastases, 3 were in stage T1N0-1M0 and 10 were in stage T2-4N0-1M0. A complete response appeared in 12 patients, whereas a partial response appeared in 1 patient. The mean survival time of the

  4. Isolated perifacial lymph node metastasis in oral squamous cell carcinoma with clinically node-negative neck.

    Science.gov (United States)

    Agarwal, Sangeet Kumar; Arora, Sowrabh Kumar; Kumar, Gopal; Sarin, Deepak

    2016-10-01

    The incidence of occult perifacial nodal disease in oral cavity squamous cell carcinoma is not well reported. The purpose of this study was to evaluate the incidence of isolated perifacial lymph node metastasis in patients with oral squamous cell carcinoma with a clinically node-negative neck. The study will shed light on current controversies and will provide valuable clinical and pathological information in the practice of routine comprehensive removal of these lymph node pads in selective neck dissection in the node-negative neck. Prospective analysis. This study was started in August 2011 when intraoperatively we routinely separated the lymph node levels from the main specimen for evaluation of the metastatic rate to different lymph node levels in 231 patients of oral squamous cell cancer with a clinically node-negative neck. The current study demonstrated that 19 (8.22%) out of 231 patients showed ipsilateral isolated perifacial lymph node involvement. The incidence of isolated perifacial nodes did not differ significantly between the oral tongue (7.14%) and buccal mucosa (7.75%). Incidence was statistically significant in cases with lower age group (oral squamous cell carcinoma with a clinically node-negative neck. The incidence of isolated perifacial involvement is high in cases of buccal mucosal and tongue cancers. A meticulous dissection of the perifacial nodes seems prudent when treating the neck in oral cavity squamous cell carcinoma. 4 Laryngoscope, 126:2252-2256, 2016. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  5. Interpolating between random walks and optimal transportation routes: Flow with multiple sources and targets

    Science.gov (United States)

    Guex, Guillaume

    2016-05-01

    In recent articles about graphs, different models proposed a formalism to find a type of path between two nodes, the source and the target, at crossroads between the shortest-path and the random-walk path. These models include a freely adjustable parameter, allowing to tune the behavior of the path toward randomized movements or direct routes. This article presents a natural generalization of these models, namely a model with multiple sources and targets. In this context, source nodes can be viewed as locations with a supply of a certain good (e.g. people, money, information) and target nodes as locations with a demand of the same good. An algorithm is constructed to display the flow of goods in the network between sources and targets. With again a freely adjustable parameter, this flow can be tuned to follow routes of minimum cost, thus displaying the flow in the context of the optimal transportation problem or, by contrast, a random flow, known to be similar to the electrical current flow if the random-walk is reversible. Moreover, a source-targetcoupling can be retrieved from this flow, offering an optimal assignment to the transportation problem. This algorithm is described in the first part of this article and then illustrated with case studies.

  6. Competition in spatial location models

    NARCIS (Netherlands)

    Webers, H.M.

    1996-01-01

    Models of spatial competition are designed and analyzed to describe the fact that space, by its very nature, is a source of market power. This field of research, lying at the interface of game theory and economics, has attracted much interest because location problems are related to many aspects of

  7. Harmonic disturbance location by applying Bayesian inference

    NARCIS (Netherlands)

    Ye, G.; Xiang, Y.; Cuk, V.; Cobben, J.F.G.

    2016-01-01

    Harmonic pollution is one of the most important power quality issues in electric power systems. Correct location of the main harmonic disturbance source is a key step to solve the problem. This paper presents a method to detect the location of harmonic disturbance source in low voltage network

  8. Node Immunization with Time-Sensitive Restrictions

    Directory of Open Access Journals (Sweden)

    Wen Cui

    2016-12-01

    Full Text Available When we encounter a malicious rumor or an infectious disease outbreak, immunizing k nodes of the relevant network with limited resources is always treated as an extremely effective method. The key challenge is how we can insulate limited nodes to minimize the propagation of those contagious things. In previous works, the best k immunised nodes are selected by learning the initial status of nodes and their strategies even if there is no feedback in the propagation process, which eventually leads to ineffective performance of their solutions. In this paper, we design a novel vaccines placement strategy for protecting much more healthy nodes from being infected by infectious nodes. The main idea of our solution is that we are not only utilizing the status of changing nodes as auxiliary knowledge to adjust our scheme, but also comparing the performance of vaccines in various transmission slots. Thus, our solution has a better chance to get more benefit from these limited vaccines. Extensive experiments have been conducted on several real-world data sets and the results have shown that our algorithm has a better performance than previous works.

  9. Bounds in the location-allocation problem

    DEFF Research Database (Denmark)

    Juel, Henrik

    1981-01-01

    Develops a family of stronger lower bounds on the objective function value of the location-allocation problem. Solution methods proposed to solve problems in location-allocation; Efforts to develop a more efficient bound solution procedure; Determination of the locations of the sources....

  10. A Family of Algorithms for Computing Consensus about Node State from Network Data

    Science.gov (United States)

    Brush, Eleanor R.; Krakauer, David C.; Flack, Jessica C.

    2013-01-01

    Biological and social networks are composed of heterogeneous nodes that contribute differentially to network structure and function. A number of algorithms have been developed to measure this variation. These algorithms have proven useful for applications that require assigning scores to individual nodes–from ranking websites to determining critical species in ecosystems–yet the mechanistic basis for why they produce good rankings remains poorly understood. We show that a unifying property of these algorithms is that they quantify consensus in the network about a node's state or capacity to perform a function. The algorithms capture consensus by either taking into account the number of a target node's direct connections, and, when the edges are weighted, the uniformity of its weighted in-degree distribution (breadth), or by measuring net flow into a target node (depth). Using data from communication, social, and biological networks we find that that how an algorithm measures consensus–through breadth or depth– impacts its ability to correctly score nodes. We also observe variation in sensitivity to source biases in interaction/adjacency matrices: errors arising from systematic error at the node level or direct manipulation of network connectivity by nodes. Our results indicate that the breadth algorithms, which are derived from information theory, correctly score nodes (assessed using independent data) and are robust to errors. However, in cases where nodes “form opinions” about other nodes using indirect information, like reputation, depth algorithms, like Eigenvector Centrality, are required. One caveat is that Eigenvector Centrality is not robust to error unless the network is transitive or assortative. In these cases the network structure allows the depth algorithms to effectively capture breadth as well as depth. Finally, we discuss the algorithms' cognitive and computational demands. This is an important consideration in systems in which

  11. Hidradenocarcinoma of the Scrotum with Lymph Node Metastasis

    Directory of Open Access Journals (Sweden)

    Maria Inês Simões

    2018-03-01

    Full Text Available Hidradenocarcinoma is a rare neoplasm of the eccrine cells of the sweat glands, usually asymptomatic with slow growing and higher incidence between 50 and 80 years, occurring in both sexes and preferentially located in the palmar, plantar, frontal, axillary and nuchal regions. It has an aggressive behavior, with high rate of local recurrence and distance metastasis, associated with a poor prognosis. We present a case of hidradenocarcinoma of the scrotum manifested by lymph node metastasis through an exercise of clinical and histological differential diagnosis of an inguinal adenopathy in a young adult.

  12. [Hidradenocarcinoma of the Scrotum with Lymph Node Metastasis].

    Science.gov (United States)

    Simões, Maria Inês; Marcão, Isabel; Toscano, Mário; Borges, Luís

    2018-03-29

    Hidradenocarcinoma is a rare neoplasm of the eccrine cells of the sweat glands, usually asymptomatic with slow growing and higher incidence between 50 and 80 years, occurring in both sexes and preferentially located in the palmar, plantar, frontal, axillary and nuchal regions. It has an aggressive behavior, with high rate of local recurrence and distance metastasis, associated with a poor prognosis. We present a case of hidradenocarcinoma of the scrotum manifested by lymph node metastasis through an exercise of clinical and histological differential diagnosis of an inguinal adenopathy in a young adult.

  13. Efficient Graph Computation for Node2Vec

    OpenAIRE

    Zhou, Dongyan; Niu, Songjie; Chen, Shimin

    2018-01-01

    Node2Vec is a state-of-the-art general-purpose feature learning method for network analysis. However, current solutions cannot run Node2Vec on large-scale graphs with billions of vertices and edges, which are common in real-world applications. The existing distributed Node2Vec on Spark incurs significant space and time overhead. It runs out of memory even for mid-sized graphs with millions of vertices. Moreover, it considers at most 30 edges for every vertex in generating random walks, causin...

  14. Checkpointing for a hybrid computing node

    Science.gov (United States)

    Cher, Chen-Yong

    2016-03-08

    According to an aspect, a method for checkpointing in a hybrid computing node includes executing a task in a processing accelerator of the hybrid computing node. A checkpoint is created in a local memory of the processing accelerator. The checkpoint includes state data to restart execution of the task in the processing accelerator upon a restart operation. Execution of the task is resumed in the processing accelerator after creating the checkpoint. The state data of the checkpoint are transferred from the processing accelerator to a main processor of the hybrid computing node while the processing accelerator is executing the task.

  15. Selective sentinel lymph node biopsy in male breast cancer.

    Science.gov (United States)

    Martin-Marcuartu, J J; Alvarez-Perez, R M; Sousa Vaquero, J M; Jimenez-Hoyuela García, J M

    To evaluate the reproducibility of the sentinel lymph node (SLN) technique in male breast cancer. We retrospectively analysed 21 male patients diagnosed with breast cancer in our hospital from 2008 to 2016 with, at least, 18 months follow-up. Fifteen patients underwent selective sentinel lymph node biopsy (SLNB) following the usual protocols with peritumoral injection of 18.5-111MBq of 99m Tc-nanocoloides and acquisition of planar images 2hours after the injection. In 2 cases it was necessary to perform a SPECT/CT to locate the SLN. Immunohistochemistry and molecular techniques (OSNA) were used for their analysis. Six patients did not undergo SLNB because they had pathological nodes or distant disease at the time of diagnosis. SLNB was performed in 15 patients. The SLN was negative in 6 patients and positive in the remaining 9. Three patients with positive SLNB did not need axillary lymphadenectomy because of the low number of copies by molecular analysis OSNA. Axillary lymphadenectomy was performed in the remaining 6 patients with the result of 4 positive axillary lymphadenectomies and 2 that did not show further extension of the disease. According to our experience, SLNB in males is a reproducible, useful, safe and reliable technique which avoids unnecessary axillary lymphadenectomy and prevents the appearance of undesirable effects. Copyright © 2017. Publicado por Elsevier España, S.L.U.

  16. Regularization of the Boundary-Saddle-Node Bifurcation

    Directory of Open Access Journals (Sweden)

    Xia Liu

    2018-01-01

    Full Text Available In this paper we treat a particular class of planar Filippov systems which consist of two smooth systems that are separated by a discontinuity boundary. In such systems one vector field undergoes a saddle-node bifurcation while the other vector field is transversal to the boundary. The boundary-saddle-node (BSN bifurcation occurs at a critical value when the saddle-node point is located on the discontinuity boundary. We derive a local topological normal form for the BSN bifurcation and study its local dynamics by applying the classical Filippov’s convex method and a novel regularization approach. In fact, by the regularization approach a given Filippov system is approximated by a piecewise-smooth continuous system. Moreover, the regularization process produces a singular perturbation problem where the original discontinuous set becomes a center manifold. Thus, the regularization enables us to make use of the established theories for continuous systems and slow-fast systems to study the local behavior around the BSN bifurcation.

  17. Onderzoek Location Based Marketing: Mobile = location = effect

    NARCIS (Netherlands)

    Gisbergen, M.S. van; Huhn, A.E.; Khan, V.J.; Ketelaar, P.E.

    2011-01-01

    Onderzoekers van de NHTV (Internationaa Hoger Onderwijs Breda, Radboud Universiteit, DVJ Insights en Popai Benelux lieten consumenten in een virtuele supermarkt advertenties via de smartphone ontvangen wanneer men langs het geadverteerde product liep. De uitkomsten laten zien dat 'location based

  18. Supine MRI for regional breast radiotherapy: imaging axillary lymph nodes before and after sentinel-node biopsy

    Science.gov (United States)

    van Heijst, Tristan C. F.; Eschbach-Zandbergen, Debora; Hoekstra, Nienke; van Asselen, Bram; Lagendijk, Jan J. W.; Verkooijen, Helena M.; Pijnappel, Ruud M.; de Waard, Stephanie N.; Witkamp, Arjen J.; van Dalen, Thijs; Desirée van den Bongard, H. J. G.; Philippens, Marielle E. P.

    2017-08-01

    Regional radiotherapy (RT) is increasingly used in breast cancer treatment. Conventionally, computed tomography (CT) is performed for RT planning. Lymph node (LN) target levels are delineated according to anatomical boundaries. Magnetic resonance imaging (MRI) could enable individual LN delineation. The purpose was to evaluate the applicability of MRI for LN detection in supine treatment position, before and after sentinel-node biopsy (SNB). Twenty-three female breast cancer patients (cTis-3N0M0) underwent 1.5 T MRI, before and after SNB, in addition to CT. Endurance for MRI was monitored. Axillary levels were delineated. LNs were identified and delineated on MRI from before and after SNB, and on CT, and compared by Wilcoxon signed-rank tests. LN locations and LN-based volumes were related to axillary delineations and associated volumes. Although postoperative effects were visible, LN numbers on postoperative MRI (median 26 LNs) were highly reproducible compared to preoperative MRI when adding excised sentinel nodes, and higher than on CT (median 11, p  <  0.001). LN-based volumes were considerably smaller than respective axillary levels. Supine MRI of LNs is feasible and reproducible before and after SNB. This may lead to more accurate RT target definition compared to CT, with potentially lower toxicity. With the MRI techniques described here, initiation of novel MRI-guided RT strategies aiming at individual LNs could be possible.

  19. Lymphoscintigraphy and triangulated body marking for morbidity reduction during sentinel node biopsy in breast cancer.

    Science.gov (United States)

    Krynyckyi, Borys R; Shafir, Michail K; Kim, Suk Chul; Kim, Dong Wook; Travis, Arlene; Moadel, Renee M; Kim, Chun K

    2005-11-08

    Current trends in patient care include the desire for minimizing invasiveness of procedures and interventions. This aim is reflected in the increasing utilization of sentinel lymph node biopsy, which results in a lower level of morbidity in breast cancer staging, in comparison to extensive conventional axillary dissection. Optimized lymphoscintigraphy with triangulated body marking is a clinical option that can further reduce morbidity, more than when a hand held gamma probe alone is utilized. Unfortunately it is often either overlooked or not fully understood, and thus not utilized. This results in the unnecessary loss of an opportunity to further reduce morbidity. Optimized lymphoscintigraphy and triangulated body marking provides a detailed 3 dimensional map of the number and location of the sentinel nodes, available before the first incision is made. The number, location, relevance based on time/sequence of appearance of the nodes, all can influence 1) where the incision is made, 2) how extensive the dissection is, and 3) how many nodes are removed. In addition, complex patterns can arise from injections. These include prominent lymphatic channels, pseudo-sentinel nodes, echelon and reverse echelon nodes and even contamination, which are much more difficult to access with the probe only. With the detailed information provided by optimized lymphoscintigraphy and triangulated body marking, the surgeon can approach the axilla in a more enlightened fashion, in contrast to when the less informed probe only method is used. This allows for better planning, resulting in the best cosmetic effect and less trauma to the tissues, further reducing morbidity while maintaining adequate sampling of the sentinel node(s).

  20. ARC Code TI: NodeMon

    Data.gov (United States)

    National Aeronautics and Space Administration — NodeMon is a resource utilization monitor tailored to the Altix architecture, but is applicable to any Linux system or cluster. It allows distributed resource...

  1. Proposal for the delineation of the nodal CTV in the node-positive and the post-operative neck

    International Nuclear Information System (INIS)

    Gregoire, Vincent; Eisbruch, Avraham; Hamoir, Marc; Levendag, Peter

    2006-01-01

    Background and purpose: In 2003, a panel of experts published a set of consensus guidelines regarding the delineation of the neck node levels (Radiother Oncol, 2003; 69: 227-36). These recommendations were applicable for the node-negative and the N1-neck, but were found too restrictive for the node-positive and the post-operative neck. Patients and methods: In this framework, using the previous recommendations as a backbone, new guidelines have been proposed taking into account the specificities of the node-positive and the post-operative neck. Results: Inclusion of the retrostyloid space cranially and the supra-clavicular fossa caudally is proposed in case of neck nodes (defined radiologically or on the surgical specimen) located in levels II, and IV or Vb, respectively. When extra-capsular rupture is suspected (on imaging) or demonstrated on the pathological specimen, adjacent muscles should also be included in the CTV. For node(s) located at the boundary between contiguous levels (e.g. levels II and Ib), these two levels should be delineated. In the post-operative setting, the entire 'surgical bed' should be included. Last, the retropharyngeal space should be delineated in case of positive neck from pharyngeal tumors. Conclusions: The objective of the manuscript is to give a comprehensive description of the new set of guidelines for CTV delineation in the node-positive neck and the post-operative neck, with a complementary atlas of the new anatomical structures to be included

  2. Resilience against Misbehaving Nodes in Asynchronous Networks

    OpenAIRE

    Senejohnny, D.; Sundaram, S.; De Persis, C.; Tesi, P.

    2018-01-01

    Network systems are one of the most active research areas in the engineering community as they feature a paradigm shift from centralized to distributed control and computation. When dealing with network systems, a fundamental challenge is to ensure their functioning even when some of the network nodes do not operate as intended due to faults or attacks. The objective of this paper is to address the problem of resilient consensus in a context where the nodes have their own clocks, possibly ope...

  3. Node insertion in Coalescence Fractal Interpolation Function

    International Nuclear Information System (INIS)

    Prasad, Srijanani Anurag

    2013-01-01

    The Iterated Function System (IFS) used in the construction of Coalescence Hidden-variable Fractal Interpolation Function (CHFIF) depends on the interpolation data. The insertion of a new point in a given set of interpolation data is called the problem of node insertion. In this paper, the effect of insertion of new point on the related IFS and the Coalescence Fractal Interpolation Function is studied. Smoothness and Fractal Dimension of a CHFIF obtained with a node are also discussed

  4. Resilience of electricity grids against transmission line overloads under wind power injection at different nodes.

    Science.gov (United States)

    Schiel, Christoph; Lind, Pedro G; Maass, Philipp

    2017-09-14

    A steadily increasing fraction of renewable energy sources for electricity production requires a better understanding of how stochastic power generation affects the stability of electricity grids. Here, we assess the resilience of an IEEE test grid against single transmission line overloads under wind power injection based on the dc power flow equations and a quasi-static grid response to wind fluctuations. Thereby we focus on the mutual influence of wind power generation at different nodes. We find that overload probabilities vary strongly between different pairs of nodes and become highly affected by spatial correlations of wind fluctuations. An unexpected behaviour is uncovered: for a large number of node pairs, increasing wind power injection at one node can increase the power threshold at the other node with respect to line overloads in the grid. We find that this seemingly paradoxical behaviour is related to the topological distance of the overloaded line from the shortest path connecting the wind nodes. In the considered test grid, it occurs for all node pairs, where the overloaded line belongs to the shortest path.

  5. Roles of preoperative lymphoscintigraphy for sentinel lymph node biopsy in breast cancer patients

    International Nuclear Information System (INIS)

    Sun Xiao; Liu Juanjuan; Wang Yongsheng; Wang Lei; Yang Guoren; Zhou Zhengbo; Li Yongqing; Liu Yanbing; Li Taiyu

    2010-01-01

    The objective of this study was to evaluate roles of preoperative lymphoscintigraphy for sentinel lymph node biopsy in breast cancer patients. Five hundred and sixty-five consecutive breast cancer patients were prospectively randomized into groups with or without preoperative lymphoscintigraphy. In a group with lymphoscintigraphy, 238 patients had sentinel lymph nodes spotted in lymphoscintigram. The visualization of sentinel lymph nodes in lymphoscintigram was not associated with patients' age, primary tumor size and location, histopathologic type and time interval from injection of radiocolloid to lymphoscintigraphy. However, patients with axillary metastasis had a lower identification rate of sentinel lymph nodes by lymphoscintigraphy than those without metastasis (P=0.003). The identification rate of axillary sentinel lymph nodes was 99.3% in the group and the rate was similar whether there was sentinel lymph nodes spotted in axillary in lymphoscintigram or not (99.6% vs. 98.1%, P=0.327). The false-negative rate in this group was 4.2%. While in a group without lymphoscintigraphy, the identification rate and the false-negative rate were 99.6% and 4.8%, respectively. There was no significant difference between the two groups in the identification rate of axillary sentinel lymph nodes (P=0.594) and in the false-negative rate (P=1.00). Preoperative lymphoscintigraphy could neither improve the identification rate nor reduce the false-negative rate of breast cancer sentinel lymph node biopsy, and it is not necessary for sentinel lymph node biopsy in breast cancer patients. (author)

  6. Anatomic distribution of supraclavicular lymph node in patients with esophageal cancer

    Directory of Open Access Journals (Sweden)

    Xing J

    2016-09-01

    Full Text Available Jun Xing,1 Yijun Luo,1,2 Xiaoli Wang,1,2 Min Gao,1 Mingping Sun,1 Xiuping Ding,1 Tingyong Fan,1 Jinming Yu1 1Department of Radiation Oncology and Radiology, Shandong Cancer Hospital Affiliated to Shandong University, 2School of Medical and Life Sciences, Shandong Academy of Medical Sciences, University of Jinan, Jinan, People’s Republic of China Purpose: Definitive chemoradiation therapy remains the standard of care for patients with localized esophageal carcinoma who choose nonsurgical management. However, there is no consensus regarding delineation of the nodal clinical target volume (CTVn, especially for lower cervical lymph nodes. This study aimed to map the location of metastatic supraclavicular lymph nodes in thoracic esophageal carcinoma patients with supraclavicular node involvement and generate an atlas to delineate the CTVn for elective nodal radiation of esophageal squamous cell carcinoma. Patients and methods: In this study, the supraclavicular regional lymph node was further divided into four subgroups. The locations of the involved supraclavicular nodes for all patients were then transferred onto a template computed tomography (CT image. A volume probability map was then generated with nodal volumes, and was displayed on the template CT to provide a visual impression of nodal frequencies and anatomic distribution. Results: We identified 154 supraclavicular nodal metastases based on CT image in 96 patients. Of these, 29.2% were located in group I region, 59.7% in group II region, 10.4% in group III region, and 0.7% in group IV region. Conclusion: On the basis of our study, we suggest that the appropriate radiation field of CTVn should include the group I and II regions and the CTVn exterior margin along the lateral side of the internal jugular vein may be suitable. Keywords: esophageal carcinoma, lymph node metastasis, clinical target volume, cervical lymph node

  7. Lymph Node Micrometastases are Associated with Worse Survival in Patients with Otherwise Node-Negative Hilar Cholangiocarcinoma

    NARCIS (Netherlands)

    Mantel, Hendrik T. J.; Wiggers, Jim K.; Verheij, Joanne; Doff, Jan J.; Sieders, Egbert; van Gulik, Thomas M.; Gouw, Annette S. H.; Porte, Robert J.

    2015-01-01

    Background. Lymph node metastases on routine histology are a strong negative predictor for survival after resection of hilar cholangiocarcinoma. Additional immunohistochemistry can detect lymph node micrometastases in patients who are otherwise node negative, but the prognostic value is unsure. The

  8. Dynamically reassigning a connected node to a block of compute nodes for re-launching a failed job

    Science.gov (United States)

    Budnik, Thomas A [Rochester, MN; Knudson, Brant L [Rochester, MN; Megerian, Mark G [Rochester, MN; Miller, Samuel J [Rochester, MN; Stockdell, William M [Byron, MN

    2012-03-20

    Methods, systems, and products for dynamically reassigning a connected node to a block of compute nodes for re-launching a failed job that include: identifying that a job failed to execute on the block of compute nodes because connectivity failed between a compute node assigned as at least one of the connected nodes for the block of compute nodes and its supporting I/O node; and re-launching the job, including selecting an alternative connected node that is actively coupled for data communications with an active I/O node; and assigning the alternative connected node as the connected node for the block of compute nodes running the re-launched job.

  9. Lymph Node Yield as a Predictor of Survival in Pathologically Node Negative Oral Cavity Carcinoma.

    Science.gov (United States)

    Lemieux, Aaron; Kedarisetty, Suraj; Raju, Sharat; Orosco, Ryan; Coffey, Charles

    2016-03-01

    Even after a pathologically node-negative (pN0) neck dissection for oral cavity squamous cell carcinoma (SCC), patients may develop regional recurrence. In this study, we (1) hypothesize that an increased number of lymph nodes removed (lymph node yield) in patients with pN0 oral SCC predicts improved survival and (2) explore predictors of survival in these patients using a multivariable model. Case series with chart review. Administrative database analysis. The SEER database was queried for patients diagnosed with all-stage oral cavity SCC between 1988 and 2009 who were determined to be pN0 after elective lymph node dissection. Demographic and treatment variables were extracted. The association of lymph node yield with 5-year all-cause survival was studied with multivariable survival analyses. A total of 4341 patients with pN0 oral SCC were included in this study. The 2 highest lymph node yield quartiles (representing >22 nodes removed) were found to be significant predictors of overall survival (22-35 nodes: hazard ratio [HR] = 0.854, P = .031; 36-98 nodes: HR = 0.827, P = .010). Each additional lymph node removed during neck dissection was associated with increased survival (HR = 0.995, P = .022). These data suggest that patients with oral SCC undergoing elective neck dissection may experience an overall survival benefit associated with greater lymph node yield. Mechanisms behind the demonstrated survival advantage are unknown. Larger nodal dissections may remove a greater burden of microscopic metastatic disease, diminishing the likelihood of recurrence. Lymph node yield may serve as an objective measure of the adequacy of lymphadenectomy. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2015.

  10. ESONET LIDO Demonstration Mission: the East Sicily node

    Science.gov (United States)

    Riccobene, Giorgio; Favali, Paolo; Andrè, Michel; Chierici, Francesco; Pavan, Gianni; Esonet Lido Demonstration Mission Team

    2010-05-01

    Off East Sicily (at 2100 m depth, 25 km off the harbour of Catania) a prototype of a cabled deep-sea observatory (NEMO-SN1) was set up and has been operational in real-time since 2005 (the cabled deep-sea multi-parameter station SN1, equipped with geophysical and environmental sensors and the cabled NEMO-OνDE, equipped with 4 broadband hydrophones). The Western Ionian Sea is one of the node sites for the upcoming European permanent underwater network (EMSO). Within the activities of the EC project ESONET-NoE some demonstration missions have been funded. The LIDO-DM (Listening to the Deep Ocean-Demonstration Mission) is one of these and is related to two sites, East Sicily and Iberian Margin (Gulf of Cadiz), the main aims being geo-hazards monitoring and warning (seismic, tsunami, and volcanic) and bio-acoustics. The LIDO-DM East Sicily installation represents a further major step within ESONET-NoE, resulting in a fully integrated system for multidisciplinary deep-sea science, capable to transmit and distribute data in real time to the scientific community and to the general public. LIDO-DM East Sicily hosts a large number of sensors aimed at monitoring and studying oceanographic and environmental parameters (by means of CTD, ADCP, 3-C single point current meter, turbidity meter), geophysical phenomena (low frequency hydrophones, accelerometer, gravity meter, vector and scalar magnetometers, seismometer, absolute and differential pressure gauges), ocean noise monitoring and identification and tracking of biological acoustic sources in deep sea. The latter will be performed using two tetrahedral arrays of 4 hydrophones, located at a relative distance of about 5 km, and at about 25 km from the shore. The whole system will be connected and powered from shore, by means of the electro-optical cable net installed at the East Sicily Site Infrastructure, and synchronised with GPS. Sensors data sampling is performed underwater and transmitted via optical fibre link, with

  11. Empirical Research of Micro-blog Information Transmission Range by Guard nodes

    Science.gov (United States)

    Chen, Shan; Ji, Ling; Li, Guang

    2018-03-01

    The prediction and evaluation of information transmission in online social networks is a challenge. It is significant to solve this issue for monitoring public option and advertisement communication. First, the prediction process is described by a set language. Then with Sina Microblog system as used as the case object, the relationship between node influence and coverage rate is analyzed by using the topology structure of information nodes. A nonlinear model is built by a statistic method in a specific, bounded and controlled Microblog network. It can predict the message coverage rate by guard nodes. The experimental results show that the prediction model has higher accuracy to the source nodes which have lower influence in social network and practical application.

  12. A 3D Two-node and One-node HCMFD Algorithm for Pin-wise Reactor Analysis

    International Nuclear Information System (INIS)

    Kim, Jaeha; Kim, Yonghee

    2016-01-01

    To maximize the parallel computational efficiency, an iterative local-global strategy is adopted in the HCMFD algorithm. The global eigenvalue problem is solved by one-node CMFD, and the local fixed-source problems are solved by two-node CMFD based on the pin-wise nodal solutions. In such local-global scheme, the computational cost is mostly concentrated in solving the local problems while they can be solved in parallel so that a parallel computing can effectively be applied. Previously, the feasibility of the HCMFD algorithm was evaluated only in a 2-D scheme. In this paper, the 3D HCMFD algorithm with some possible variations in treating the axial direction is introduced. The HCMFD algorithm was successfully extended to a 3-D core analysis without any numerical instability even though the axial mesh size in local problems is quite different from the x-y node size. We have shown that 3D pin-wise core analysis can be done very effectively with the HCMFD framework. Additionally, it was demonstrated that parallel efficiency of the new 3D HCMFD scheme can be quite high on a simple OpenMP parallel architecture. It is concluded that the 3D HCMFD will enable an efficient pin-wise 3D core analysis

  13. Location | FNLCR Staging

    Science.gov (United States)

    The Frederick National Laboratory for Cancer Research campus is located 50 miles northwest of Washington, D.C., and 50 miles west of Baltimore, Maryland, in Frederick, Maryland. Satellite locations include leased and government facilities extending s

  14. Appraising manufacturing location

    NARCIS (Netherlands)

    Steenhuis, H.J.; de Bruijn, E.J.

    2002-01-01

    International location of manufacturing activities is an issue for managers of manufacturing companies as well as public policy makers. For managers, the issue is relevant because international locations offer opportunities for lowering costs due to productivity improvements. For governments the

  15. Law Enforcement Locations

    Data.gov (United States)

    Kansas Data Access and Support Center — Law Enforcement Locations in Kansas Any location where sworn officers of a law enforcement agency are regularly based or stationed. Law enforcement agencies "are...

  16. Distribution of involved regional lymph nodes in recurrent and locally advanced breast cancer and its impact on target definition

    International Nuclear Information System (INIS)

    Chen Jian; Ma Jinli; Zhang Shengjian; Yang Zhaozhi; Cai Gang; Feng Yan; Guo Xiaomao; Chen Jiayi

    2011-01-01

    Objective: The frequency and the anatomic distribution of involved regional nodes in recurrent and locally advanced breast cancer were analyzed, in order to evaluate the rational of conventional regional node radiation technique and provide evidence for target definition of breast cancer . Methods: Patients with recurrent or locally advanced breast cancer who were treated in our hospital from August 2003 to December 2009 were included in this study. 111 patients had contrast enhanced chest CT images of the whole regional nodes before treatment. The regional nodes were categorized into 8 anatomical substructures including medial and lateral supraclavicular nodes ( SC-M, SC-L), axilla nodes ( ALN )- I , II , III, infra clavicular nodes (IFN), Rotter's nodes (RN) and internal mammary nodes (IMN). The frequency of involvement and anatomical distribution of the involved nodes on CT images were analyzed. Results: A total of 111 patients were enrolled this study and 199 anatomical substructures with involved nodes were identified. The frequency of involvement were : SC-M 33, SC-L 21, ALN- I 30, ALN-II 25, ALN-III + IFN 35, RN 27, IMN 28. Supraclavicular region and axilla were the most frequently involved area (72.3%). The average depth of the SC-M and SC-L nodes was 33.48 mm ± 10. 57 mm and 45.62 mm ±20. 45 mm, and 51.5% and 71.4% of the SC-M and SC-L nodes were located more than 3 cm deep from the skin. The axilla nodes were located cranial and caudal to the axillary vein in 5 and 20 locally advanced breast cancer patients and in 64 and 28 patients who received prior axillary dissection. The majority of involved IMN was located within the first 3 intercostal spaces (26/28). The average distance between the center of involved IMN and chest skin was 24. 23 mm ± 10. 28 mm. The average distance between the center of involved IMN and midline of the body was 29. 38 mm ±6. 7 mm. The center of involved IMN was 6.19 mm ±5.73 mm lateral and 5.73 mm ± 4. 56 mm posterior to

  17. Use of Tc-99m - nanocolloid for sentinel node indentification in cervical cancer

    International Nuclear Information System (INIS)

    Hubalewska, A.; Sowa-Staszczak, A.; Huszczno, B.; Markocka, A.; Pitynski, K.; Basta, A.; Oplawski, M.; Basta, P.

    2003-01-01

    patients had those located bilaterally. Histologically positive SNs were found in 5 women (13.5%). A combination pre-operatively administered radioactively labelled albumin with blue dye allows the successful detection of SN in patient with cervical cancer. This technique will result in a real advance in the less aggressive management of patients with early stage cervical cancer. Sentinel lymph node status may be representative of the pelvic lymph nodes status in cervical cancer and thus could provide important information for further treatment. (author)

  18. Impact of a half-space interface on the wireless link between tiny sensor nodes

    NARCIS (Netherlands)

    Penkin, D.; Janssen, G.; Yarovoy, A.

    2014-01-01

    The power budget of a wireless link between two electrically small sensor nodes located close to an interface between two media is studied. The model includes both the propagation channel losses and input impedance of the radio frequency antennas. It is shown that a highly inductive half-space

  19. Smartphones as locative media

    CERN Document Server

    Frith, Jordan

    2015-01-01

    Smartphone adoption has surpassed 50% of the population in more than 15 countries, and there are now more than one million mobile applications people can download to their phones. Many of these applications take advantage of smartphones as locative media, which is what allows smartphones to be located in physical space. Applications that take advantage of people's location are called location-based services, and they are the focus of this book. Smartphones as locative media raise important questions about how we understand the complicated relationship between the Internet and physical space

  20. Efficient Hybrid Detection of Node Replication Attacks in Mobile Sensor Networks

    Directory of Open Access Journals (Sweden)

    Ze Wang

    2017-01-01

    Full Text Available The node replication attack is one of the notorious attacks that can be easily launched by adversaries in wireless sensor networks. A lot of literatures have studied mitigating the node replication attack in static wireless sensor networks. However, it is more difficult to detect the replicas in mobile sensor networks because of their node mobility. Considering the limitations of centralized detection schemes for static wireless sensor networks, a few distributed solutions have been recently proposed. Some existing schemes identified replicated attacks by sensing mobile nodes with identical ID but different locations. To facilitate the discovery of contradictory conflicts, we propose a hybrid local and global detection method. The local detection is performed in a local area smaller than the whole deployed area to improve the meeting probability of contradictory nodes, while the distant replicated nodes in larger area can also be efficiently detected by the global detection. The complementary two levels of detection achieve quick discovery by searching of the replicas with reasonable overhead.

  1. Vertebral morphology influences the development of Schmorl's nodes in the lower thoracic vertebrae.

    Science.gov (United States)

    Plomp, Kimberly A; Roberts, Charlotte A; Viðarsdóttir, Una Strand

    2012-12-01

    Schmorl's nodes are the result of herniations of the nucleus pulposus into the adjacent vertebral body and are commonly identified in both clinical and archaeological contexts. The current study aims to identify aspects of vertebral shape that correlate with Schmorl's nodes. Two-dimensional statistical shape analysis was performed on digital images of the lower thoracic spine (T10-T12) of adult skeletons from the late medieval skeletal assemblages from Fishergate House, York, St. Mary Graces and East Smithfield Black Death cemeteries, London, and postmedieval Chelsea Old Church, London. Schmorl's nodes were scored on the basis of their location, depth, and size. Results indicate that there is a correlation between the shape of the posterior margin of the vertebral body and pedicles and the presence of Schmorl's nodes in the lower thoracic spine. The size of the vertebral body in males was also found to correlate with the lesions. Vertebral shape differences associated with the macroscopic characteristics of Schmorl's nodes, indicating severity of the lesion, were also analyzed. The shape of the pedicles and the posterior margin of the vertebral body, along with a larger vertebral body size in males, have a strong association with both the presence and severity of Schmorl's nodes. This suggests that shape and/or size of these vertebral components are predisposing to, or resulting in, vertically directed disc herniation. Copyright © 2012 Wiley Periodicals, Inc.

  2. Hydrocarbon Status of Alluvial Soils in the Istra Morphostructural Node (Moscow Oblast)

    Science.gov (United States)

    Pikovskiy, Yu. I.; Gennadiev, A. N.; Kovach, R. G.; Khlynina, N. I.; Khlynina, A. V.

    2017-12-01

    The effect of the current block structure of the earth's crust and its most active sites (morphostructural nodes) on the natural hydrocarbon status of alluvial soils has been considered. Studies have been performed in the Istra district of Moscow oblast within the Istra morphostructural node. The node represents an area of increased geodynamic activity of the earth's crust located at the convergence or intersection of block boundaries: mobile linear zones following large river valleys with alluvial soils. Soil cover mainly consists of alluvial humic-gley soils (Eutric Gleyic Fluvisols) of different depths and alluvial mucky-gley soils (Eutric Gleyic Histic Fluvisols). Some soils manifest stratification. Two factors forming the hydrocarbon status of soils are considered: soil processes and the effect of geodynamic activity, which is manifested within the morphostructural node. The contents of bitumoids and retained methane and butanes in alluvial soils appreciably increase at the entry of river valley into the node. The occurrence frequency of 5-6-ring polycyclic aromatic hydrocarbons (perylene and benzo[ghi]perylene) in mineral horizons increases. It has been concluded that alluvial soils within the Istra morphostructural node are characterized by the biogeochemical type of hydrocarbon status with signs of emanation type at sites with the highest geodynamic activity.

  3. GWO-LPWSN: Grey Wolf Optimization Algorithm for Node Localization Problem in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    R. Rajakumar

    2017-01-01

    Full Text Available Seyedali Mirjalili et al. (2014 introduced a completely unique metaheuristic technique particularly grey wolf optimization (GWO. This algorithm mimics the social behavior of grey wolves whereas it follows the leadership hierarchy and attacking strategy. The rising issue in wireless sensor network (WSN is localization problem. The objective of this problem is to search out the geographical position of unknown nodes with the help of anchor nodes in WSN. In this work, GWO algorithm is incorporated to spot the correct position of unknown nodes, so as to handle the node localization problem. The proposed work is implemented using MATLAB 8.2 whereas nodes are deployed in a random location within the desired network area. The parameters like computation time, percentage of localized node, and minimum localization error measures are utilized to analyse the potency of GWO rule with other variants of metaheuristics algorithms such as particle swarm optimization (PSO and modified bat algorithm (MBA. The observed results convey that the GWO provides promising results compared to the PSO and MBA in terms of the quick convergence rate and success rate.

  4. Value of irradiation of neck nodes metastases. Pt. 1. Treatment of palpable nodes

    International Nuclear Information System (INIS)

    Bujko, K.

    1993-01-01

    Medical records of 222 patients with neck nodes metastases from squamous cell carcinoma of supraglottic larynx, tonsil and base of tongue were analyzed. All cases were treated with definitive irradiation. 110 patients were treated with orthovoltage technique with total doses of 5000-6000 rads, 150-10 rads per fraction; 112 patients with Co-60 with total doses 6000-7000 rads, 180-230 rads per fraction. Local-regional control was achieved in 28% of cases. Failures in the neck nodes with primary tumor controlled, were recorded in 10% of patients. Failures in a primary tumor alone were observed in 26% of patients, in primary tumor and neck nodes in 36%. Radiocurability of primary tumor and involved neck nodes was similar. In cases with primary tumor controlled, the probability of eradication of neck nodes metastases is high, even in N3 stage patients. Residual neck nodes palpable 1 to 3 months after irradiation were unfavorable prognostic factor indicated 50% risk of neck recurrence. In patients with complete regression of primary and nodal disease, failure in neck nodes was recorded in 5% of cases. The role of surgery following irradiation in patients with cervical nodes metastases is discussed. (author)

  5. Axillary lymph nodes and arm lymphatic drainage pathways are spared during routine complete axillary clearance in majority of women undergoing breast cancer surgery.

    Science.gov (United States)

    Szuba, A; Chachaj, Z; Koba-Wszedybylb, M; Hawro, R; Jasinski, R; Tarkowski, R; Szewczyk, K; Bebenek, M; Forgacz, J; Jodkowska, A; Jedrzejuk, D; Janczak, D; Mrozinska, M; Pilch, U; Wozniewski, M

    2011-09-01

    Alterations in axillary lymph nodes (ALNs) after complete axillary lymph node dissection (ALND) in comparison to the preoperative status were evaluated using lymphoscintigraphy performed preoperatively and 1-6 weeks after surgery in 30 women with a new diagnosis of unilateral, invasive breast carcinoma. Analysis of lymphoscintigrams revealed that ALNs after surgery were present in 26 of 30 examined women. In comparison to preoperative status, they were visualized in the same location (12 women), in the same and additionally in different locations (9 women), or only in different locations (4 women). No lymph nodes were visualized in one woman and lymphocoele were in 4 women. Thus, after ALND, a variable number of axillary lymph nodes remain and were visualized on lymphoscintigraphy in the majority of women. The classical ALND, therefore, does not allow complete dissection and removal of axillary nodes with total disruption of axillary lymphatic pathways, accounting in part for the variable incidence and severity of lymphedema after the procedure.

  6. Identification of the sentinel lymph node in patients with malignant melanoma: what are the reasons for mistakes?

    International Nuclear Information System (INIS)

    Vidal-Sicart, Sergi; Pons, Francesca; Puig, Susana; Vilalta, Antonio; Palou, J.M.; Castel, Teresa; Ortega, Marisa; Martin, Francisco; Rull, Ramon

    2003-01-01

    , difficult lymph node location or absence of a thorough histological study. Nevertheless, it is not possible to explain completely why, in a very small percentage of cases, the sentinel node is erroneously identified. (orig.)

  7. Distribution of prostate nodes: a PET/CT-derived anatomic atlas of prostate cancer patients before and after surgical treatment.

    Science.gov (United States)

    Hegemann, Nina-Sophie; Wenter, Vera; Spath, Sonja; Kusumo, Nadia; Li, Minglun; Bartenstein, Peter; Fendler, Wolfgang P; Stief, Christian; Belka, Claus; Ganswindt, Ute

    2016-03-11

    In order to define adequate radiation portals in nodal positive prostate cancer a detailed knowledge of the anatomic lymph-node distribution is mandatory. We therefore systematically analyzed the localization of Choline PET/CT positive lymph nodes and compared it to the RTOG recommendation of pelvic CTV, as well as to previous work, the SPECT sentinel lymph node atlas. Thirty-two patients being mostly high risk patients with a PSA of 12.5 ng/ml (median) received PET/CT before any treatment. Eighty-seven patients received PET/CT for staging due to biochemical failure with a median PSA of 3.12 ng/ml. Each single PET-positive lymph node was manually contoured in a "virtual" patient dataset to achieve a 3-D visualization, resulting in an atlas of the cumulative PET positive lymph node distribution. Further the PET-positive lymph node location in each patient was assessed with regard to the existence of a potential geographic miss (i.e. PET-positive lymph nodes that would not have been treated adequately by the RTOG consensus on CTV definition of pelvic lymph nodes). Seventy-eight and 209 PET positive lymph nodes were detected in patients with no prior treatment and in postoperative patients, respectively. The most common sites of PET positive lymph nodes in patients with no prior treatment were external iliac (32.1 %), followed by common iliac (23.1 %) and para-aortic (19.2 %). In postoperative patients the most common sites of PET positive lymph nodes were common iliac (24.9 %), followed by external iliac (23.0 %) and para-aortic (20.1 %). In patients with no prior treatment there were 34 (43.6 %) and in postoperative patients there were 77 (36.8 %) of all detected lymph nodes that would not have been treated adequately using the RTOG CTV. We compared the distribution of lymph nodes gained by Choline PET/CT to the preexisting SPECT sentinel lymph node atlas and saw an overall good congruence. Choline PET/CT and SPECT sentinel lymph node atlas are comparable to each

  8. A Secure Localization Approach Using Mutual Authentication and Insider Node Validation in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Gulshan Kumar

    2017-01-01

    Full Text Available Localization is a concerning issue in the applications of wireless sensor networks. Along with the accuracy of the location estimation of the sensor nodes, the security of the estimation is another priority. Wireless sensor networks often face various attacks where the attackers try to manipulate the estimated location or try to provide false beacons. In this paper, we have proposed a methodology that will address this problem of security aspects in localization of the sensor nodes. Moreover, we have considered the network environment with random node deployment and mobility as these two conditions are less addressed in previous research works. Further, our proposed algorithm provides low overhead due to the usage of less control messages in a limited transmission range. In addition, we have also proposed an algorithm to detect the malicious anchor nodes inside the network. The simulated results show that our proposed algorithm is efficient in terms of time consumption, localization accuracy, and localization ratio in the presence of malicious nodes.

  9. Measure of Node Similarity in Multilayer Networks

    DEFF Research Database (Denmark)

    Møllgaard, Anders; Zettler, Ingo; Dammeyer, Jesper

    2016-01-01

    The weight of links in a network is often related to the similarity of thenodes. Here, we introduce a simple tunable measure for analysing the similarityof nodes across different link weights. In particular, we use the measure toanalyze homophily in a group of 659 freshman students at a large...... university.Our analysis is based on data obtained using smartphones equipped with customdata collection software, complemented by questionnaire-based data. The networkof social contacts is represented as a weighted multilayer network constructedfrom different channels of telecommunication as well as data...... might bepresent in one layer of the multilayer network and simultaneously be absent inthe other layers. For a variable such as gender, our measure reveals atransition from similarity between nodes connected with links of relatively lowweight to dis-similarity for the nodes connected by the strongest...

  10. SpicyNodes Radial Map Engine

    Science.gov (United States)

    Douma, M.; Ligierko, G.; Angelov, I.

    2008-10-01

    The need for information has increased exponentially over the past decades. The current systems for constructing, exploring, classifying, organizing, and searching information face the growing challenge of enabling their users to operate efficiently and intuitively in knowledge-heavy environments. This paper presents SpicyNodes, an advanced user interface for difficult interaction contexts. It is based on an underlying structure known as a radial map, which allows users to manipulate and interact in a natural manner with entities called nodes. This technology overcomes certain limitations of existing solutions and solves the problem of browsing complex sets of linked information. SpicyNodes is also an organic system that projects users into a living space, stimulating exploratory behavior and fostering creative thought. Our interactive radial layout is used for educational purposes and has the potential for numerous other applications.

  11. Node-based analysis of species distributions

    DEFF Research Database (Denmark)

    Borregaard, Michael Krabbe; Rahbek, Carsten; Fjeldså, Jon

    2014-01-01

    overrepresentation score (SOS) and the geographic node divergence (GND) score, which together combine ecological and evolutionary patterns into a single framework and avoids many of the problems that characterize community phylogenetic methods in current use.This approach goes through each node in the phylogeny...... with case studies on two groups with well-described biogeographical histories: a local-scale community data set of hummingbirds in the North Andes, and a large-scale data set of the distribution of all species of New World flycatchers. The node-based analysis of these two groups generates a set...... of intuitively interpretable patterns that are consistent with current biogeographical knowledge.Importantly, the results are statistically tractable, opening many possibilities for their use in analyses of evolutionary, historical and spatial patterns of species diversity. The method is implemented...

  12. [Radiotherapy in node-positive prostate cancer].

    Science.gov (United States)

    Bottke, D; Bartkowiak, D; Bolenz, C; Wiegel, T

    2016-03-01

    There are numerous randomized trials to guide the management of patients with localized (and metastatic) prostate cancer, but only a few (mostly retrospective) studies have specifically addressed node-positive patients. Therefore, there is uncertainty regarding optimal treatment in this situation. Current guidelines recommend long-term androgen deprivation therapy (ADT) alone or radiotherapy plus long-term ADT as treatment options. This overview summarizes the existing literature on the use of radiotherapy for node-positive prostate cancer as definitive treatment and as adjuvant or salvage therapy after radical prostatectomy. In this context, we also discuss several PET tracers in the imaging evaluation of patients with biochemical recurrence of prostate cancer after radical prostatectomy. As for definitive treatment, retrospective studies suggest that ADT plus radiotherapy improves overall survival compared with ADT alone. These studies also consistently demonstrated that many patients with node-positive prostate cancer can achieve long-term survival - and are likely curable - with aggressive therapy. The beneficial impact of adjuvant radiotherapy on survival in patients with pN1 prostate cancer seems to be highly influenced by tumor characteristics. Men with ≤ 2 positive lymph nodes in the presence of intermediate- to high-grade disease, or positive margins, and those with 3 or 4 positive lymph nodes are the ideal candidates for adjuvant radiotherapy (plus long-term ADT) after surgery. There is a need for randomized trials to further examine the potential role of radiotherapy as either definitive or adjuvant treatment, for patients with node-positive prostate cancer.

  13. Lost in Location

    DEFF Research Database (Denmark)

    Hansen, Lone Koefoed

    2009-01-01

    traversed. While becoming destination aware, the individual loses her location awareness. The article proposes that the reason people get lost when using sat-nav is due to a wrong location-performative paradigm. As an alternative, the article introduces and analyzes two performance-related examples...... that illustrate an alternative location-performative paradigm: Meredith Warner's Lost/Found knitting series and Etter and Schecht's Melodious Walkabout. In both examples, the artist's hand becomes the intermediary between alien and location. Thus, by exploring how wayfinding can be a poetically situated...... performance, the article examines how the growing locative media industry can learn from the location-aware performative strategies employed by artists who create situated and urban performances for the curious participant. The academic frames employed in the analysis draw on psychogeography, site...

  14. Towards Interactive, Incremental Programming of ROS Nodes

    DEFF Research Database (Denmark)

    Adam, Marian Sorin; Schultz, Ulrik Pagh

    Writing software for controlling robots is a complex task, usually demanding command of many programming languages and requiring significant experimentation. We believe that a bottom-up development process that complements traditional component- and MDSD-based approaches can facilitate...... experimentation. We propose the use of an internal DSL providing both a tool to interactively create ROS nodes and a behaviour-replacement mechanism to interactively reshape existing ROS nodes by wrapping the external interfaces (the publish/subscribe topics), dynamically controlled using the Python command line...

  15. Refining Nodes and Edges of State Machines

    DEFF Research Database (Denmark)

    Hallerstede, Stefan; Snook, Colin

    2011-01-01

    State machines are hierarchical automata that are widely used to structure complex behavioural specifications. We develop two notions of refinement of state machines, node refinement and edge refinement. We compare the two notions by means of examples and argue that, by adopting simple conventions...... refinement theory and UML-B state machine refinement influences the style of node refinement. Hence we propose a method with direct proof of state machine refinement avoiding the detour via Event-B that is needed by UML-B....

  16. Simultaneous dual pathology in lymph node

    Directory of Open Access Journals (Sweden)

    Prakas Kumar Mandal

    2014-05-01

    Full Text Available [Abstract] Tubercuous lymphadenitis and Non Hodgkins’ Lymphoma are common in India. As both diseases can occur in elderly persons there is a definite chance of co-existence of both diseases; but that coexistence has not been reported. Here we present a unique case in an elderly woman who had synchronous double pathology of tuberculosis (TB and Diffuse Large B cell Lymphoma (DLBCL of the lymph nodes.     Key words:- lymph nodes, tuberculosis (TB, Diffuse Large B cell Lymphoma (DLBCL.

  17. Measure of Node Similarity in Multilayer Networks

    DEFF Research Database (Denmark)

    Møllgaard, Anders; Zettler, Ingo; Dammeyer, Jesper

    2016-01-01

    university.Our analysis is based on data obtained using smartphones equipped with customdata collection software, complemented by questionnaire-based data. The networkof social contacts is represented as a weighted multilayer network constructedfrom different channels of telecommunication as well as data...... might bepresent in one layer of the multilayer network and simultaneously be absent inthe other layers. For a variable such as gender, our measure reveals atransition from similarity between nodes connected with links of relatively lowweight to dis-similarity for the nodes connected by the strongest...

  18. Internet Geo-Location

    Science.gov (United States)

    2017-12-01

    INTERNET GEO-LOCATION DUKE UNIVERSITY DECEMBER 2017 FINAL TECHNICAL REPORT APPROVED FOR PUBLIC RELEASE; DISTRIBUTION UNLIMITED STINFO COPY AIR...REPORT TYPE FINAL TECHNICAL REPORT 3. DATES COVERED (From - To) MAY 2014 – MAY 2017 4. TITLE AND SUBTITLE INTERNET GEO-LOCATION 5a. CONTRACT...of SpeedTest servers that are used by end users to measure the speed of their Internet connection. The servers log the IP address and the location

  19. nodeGame: Real-time, synchronous, online experiments in the browser.

    Science.gov (United States)

    Balietti, Stefano

    2017-10-01

    nodeGame is a free, open-source JavaScript/ HTML5 framework for conducting synchronous experiments online and in the lab directly in the browser window. It is specifically designed to support behavioral research along three dimensions: (i) larger group sizes, (ii) real-time (but also discrete time) experiments, and (iii) batches of simultaneous experiments. nodeGame has a modular source code, and defines an API (application programming interface) through which experimenters can create new strategic environments and configure the platform. With zero-install, nodeGame can run on a great variety of devices, from desktop computers to laptops, smartphones, and tablets. The current version of the software is 3.0, and extensive documentation is available on the wiki pages at http://nodegame.org .

  20. Smart Location Database - Service

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Smart Location Database (SLD) summarizes over 80 demographic, built environment, transit service, and destination accessibility attributes for every census block...

  1. Smart Location Database - Download

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Smart Location Database (SLD) summarizes over 80 demographic, built environment, transit service, and destination accessibility attributes for every census block...

  2. Tumor implantation model for rapid testing of lymphatic dye uptake from paw to node in small animals

    Science.gov (United States)

    DSouza, Alisha V.; Elliott, Jonathan T.; Gunn, Jason R.; Barth, Richard J.; Samkoe, Kimberley S.; Tichauer, Kenneth M.; Pogue, Brian W.

    2015-03-01

    Morbidity and complexity involved in lymph node staging via surgical resection and biopsy calls for staging techniques that are less invasive. While visible blue dyes are commonly used in locating sentinel lymph nodes, since they follow tumor-draining lymphatic vessels, they do not provide a metric to evaluate presence of cancer. An area of active research is to use fluorescent dyes to assess tumor burden of sentinel and secondary lymph nodes. The goal of this work was to successfully deploy and test an intra-nodal cancer-cell injection model to enable planar fluorescence imaging of a clinically relevant blue dye, specifically methylene blue - used in the sentinel lymph node procedure - in normal and tumor-bearing animals, and subsequently segregate tumor-bearing from normal lymph nodes. This direct-injection based tumor model was employed in athymic rats (6 normal, 4 controls, 6 cancer-bearing), where luciferase-expressing breast cancer cells were injected into axillary lymph nodes. Tumor presence in nodes was confirmed by bioluminescence imaging before and after fluorescence imaging. Lymphatic uptake from the injection site (intradermal on forepaw) to lymph node was imaged at approximately 2 frames/minute. Large variability was observed within each cohort.

  3. A high-efficiency self-powered wireless sensor node for monitoring concerning vibratory events

    Science.gov (United States)

    Xu, Dacheng; Li, Suiqiong; Li, Mengyang; Xie, Danpeng; Dong, Chuan; Li, Xinxin

    2017-09-01

    This paper presents a self-powered wireless alarming sensor node (SWASN), which was designed to monitor the occurrence of concerning vibratory events. The major components of the sensor node include a vibration-threshold-triggered energy harvester (VTTEH) that powers the sensor node, a dual threshold voltage control circuit (DTVCC) for power management and a radio frequency (RF) signal transmitting module. The VTTEH generates significant electric energy only when the input vibration reaches certain amplitude. Thus, the VTTEH serves as both the power source and the vibration-event-sensing element for the sensor node. The DTVCC was specifically designed to utilize the limited power supply from the VTTEH to operate the sensor node. Constructed with only voltage detectors and MOSFETs, the DTVCC achieved low power consumption, which was 65% lower compared with the power management circuit designed in our previous work. Meanwhile, a RF transmit circuit was constructed based on the commercially available CC1110-F32 wireless transceiver chip and a compact planar antenna was designed to improve the signal transmission distance. The sensor node was fabricated and was characterized both in the laboratory and in the field. Experimental results showed that the SWASN could automatically send out alarming signals when the simulated concerning event occurred. The waiting time between two consecutive transmission periods is less than 125 s and the transmission distance can reach 1.31 km. The SWASN will have broad applications in field surveillances.

  4. Detection of sentinel nodes with radiopharmaceuticals

    International Nuclear Information System (INIS)

    Yokoyama, Kunihiko; Michigishi, Takatoshi; Kinuya, Seigo; Konishi, Shota; Nakajima, Kenichi; Tonami, Norihisa

    2000-01-01

    Sentinel lymph nodes have been found to be an indicator of lymph node metastasis in breast cancer. In Japan, the theory and concept of sentinel lymph nodes in breast cancer have begun to be applied to carcinomas of the digestive system. Based on clinical experience in the detection of sentinel lymph nodes with radiopharmaceuticals, differences and similarities between the radiopharmaceuticals, methods, and techniques used to detect sentinel lymph nodes have been assessed in relation to breast cancer and carcinomas of the digestive system (including carcinomas of the esophagus and large intestine). The greatest difference between the methods used for breast and digestive cancers is the site of administration of the radiopharmaceutical. In breast cancer, the radiopharmaceutical is administered into a superficial organ (i.e., the mammary gland), whereas in carcinomas of the digestive system, it is administered into a deep organ (i.e., digestive tract). Another obvious difference is in lymph flow, i.e., the flow of the mammary glands is subcutaneous whereas lymph flow in the digestive tract is submucosal. Two radionuclide diagnostic methods are available to detect sentinel lymph nodes: sentinel lymphoscintigraphy with a gamma camera and a method that involves the use of a gamma probe intraoperatively. Radiopharmaceuticals used to detect sentinel lymph nodes must be smoothly transferred from the site of administration into the lymph, and uptake by the sentinel lymph node must continue for a long time without excessive flowing to lower reaches. The optimal particle size remains a matter of controversy, and no radiopharmaceuticals appropriate for lymphoscintigraphy have ever been approved in Japan. The authors compared the pharmacokinetics of three different radiopharmaceuticals used for sentinel lymphoscintigraphy in breast cancer ( 99m Tc-labeled albumin, 99m Tc-labeled tin colloid, and 99m Tc-labeled phytic acid) and founded that the detection rate was lowest with

  5. Green facility location

    NARCIS (Netherlands)

    Velázquez Martínez, J.C.; Fransoo, J.C.; Bouchery, Y.; Corbett, C.J.; Fransoo, J.C.; Tan, T.

    2017-01-01

    Transportation is one of the main contributing factors of global carbon emissions, and thus, when dealing with facility location models in a distribution context, transportation emissions may be substantially higher than the emissions due to production or storage. Because facility location models

  6. Industrial location and competitiveness

    NARCIS (Netherlands)

    S. Brakman (Steven); J.H. Garretsen (Harry); J.G.M. van Marrewijk (Charles)

    2006-01-01

    textabstractThe interaction between the extent of location advantages and the intensity of firm competition relative to the size of the market jointly determines the location of industrial activity. Technology, factor endowments, geography, and scale economies are influential for determining

  7. Measure of Node Similarity in Multilayer Networks.

    Directory of Open Access Journals (Sweden)

    Anders Mollgaard

    Full Text Available The weight of links in a network is often related to the similarity of the nodes. Here, we introduce a simple tunable measure for analysing the similarity of nodes across different link weights. In particular, we use the measure to analyze homophily in a group of 659 freshman students at a large university. Our analysis is based on data obtained using smartphones equipped with custom data collection software, complemented by questionnaire-based data. The network of social contacts is represented as a weighted multilayer network constructed from different channels of telecommunication as well as data on face-to-face contacts. We find that even strongly connected individuals are not more similar with respect to basic personality traits than randomly chosen pairs of individuals. In contrast, several socio-demographics variables have a significant degree of similarity. We further observe that similarity might be present in one layer of the multilayer network and simultaneously be absent in the other layers. For a variable such as gender, our measure reveals a transition from similarity between nodes connected with links of relatively low weight to dis-similarity for the nodes connected by the strongest links. We finally analyze the overlap between layers in the network for different levels of acquaintanceships.

  8. Network Design with Node Degree Balance Constraints

    DEFF Research Database (Denmark)

    Pedersen, Michael Berliner; Crainic, Teodor Gabriel

    This presentation discusses an extension to the network design model where there in addition to the flow conservation constraints also are constraints that require design conservation. This means that the number of arcs entering and leaving a node must be the same. As will be shown the model has ...

  9. A Survey of Sound Source Localization Methods in Wireless Acoustic Sensor Networks

    Directory of Open Access Journals (Sweden)

    Maximo Cobos

    2017-01-01

    Full Text Available Wireless acoustic sensor networks (WASNs are formed by a distributed group of acoustic-sensing devices featuring audio playing and recording capabilities. Current mobile computing platforms offer great possibilities for the design of audio-related applications involving acoustic-sensing nodes. In this context, acoustic source localization is one of the application domains that have attracted the most attention of the research community along the last decades. In general terms, the localization of acoustic sources can be achieved by studying energy and temporal and/or directional features from the incoming sound at different microphones and using a suitable model that relates those features with the spatial location of the source (or sources of interest. This paper reviews common approaches for source localization in WASNs that are focused on different types of acoustic features, namely, the energy of the incoming signals, their time of arrival (TOA or time difference of arrival (TDOA, the direction of arrival (DOA, and the steered response power (SRP resulting from combining multiple microphone signals. Additionally, we discuss methods not only aimed at localizing acoustic sources but also designed to locate the nodes themselves in the network. Finally, we discuss current challenges and frontiers in this field.

  10. Attractive target wave patterns in complex networks consisting of excitable nodes

    International Nuclear Information System (INIS)

    Zhang Li-Sheng; Mi Yuan-Yuan; Liao Xu-Hong; Qian Yu; Hu Gang

    2014-01-01

    This review describes the investigations of oscillatory complex networks consisting of excitable nodes, focusing on the target wave patterns or say the target wave attractors. A method of dominant phase advanced driving (DPAD) is introduced to reveal the dynamic structures in the networks supporting oscillations, such as the oscillation sources and the main excitation propagation paths from the sources to the whole networks. The target center nodes and their drivers are regarded as the key nodes which can completely determine the corresponding target wave patterns. Therefore, the center (say node A) and its driver (say node B) of a target wave can be used as a label, (A,B), of the given target pattern. The label can give a clue to conveniently retrieve, suppress, and control the target waves. Statistical investigations, both theoretically from the label analysis and numerically from direct simulations of network dynamics, show that there exist huge numbers of target wave attractors in excitable complex networks if the system size is large, and all these attractors can be labeled and easily controlled based on the information given by the labels. The possible applications of the physical ideas and the mathematical methods about multiplicity and labelability of attractors to memory problems of neural networks are briefly discussed. (topical review - statistical physics and complex systems)

  11. Sentinel lymph nodes detection with an imaging system using Patent Blue V dye as fluorescent tracer

    Science.gov (United States)

    Tellier, F.; Steibel, J.; Chabrier, R.; Rodier, J. F.; Pourroy, G.; Poulet, P.

    2013-03-01

    Sentinel lymph node biopsy is the gold standard to detect metastatic invasion from primary breast cancer. This method can help patients avoid full axillary chain dissection, thereby decreasing the risk of morbidity. We propose an alternative to the traditional isotopic method, to detect and map the sentinel lymph nodes. Indeed, Patent Blue V is the most widely used dye in clinical routine for the visual detection of sentinel lymph nodes. A Recent study has shown the possibility of increasing the fluorescence quantum yield of Patent Blue V, when it is bound to human serum albumin. In this study we present a preclinical fluorescence imaging system to detect sentinel lymph nodes labeled with this fluorescent tracer. The setup is composed of a black and white CCD camera and two laser sources. One excitation source with a laser emitting at 635 nm and a second laser at 785 nm to illuminate the region of interest. The prototype is operated via a laptop. Preliminary experiments permitted to determine the device sensitivity in the μmol.L-1 range as regards the detection of PBV fluorescence signals. We also present a preclinical evaluation performed on Lewis rats, during which the fluorescence imaging setup detected the accumulation and fixation of the fluorescent dye on different nodes through the skin.

  12. Mesenteric lymph nodes in children: what is normal?

    International Nuclear Information System (INIS)

    Karmazyn, Boaz; Werner, Elizabeth A.; Rejaie, Babak; Applegate, Kimberly E.

    2005-01-01

    Enlarged mesenteric lymph nodes (MLN) are frequently seen in children with abdominal pain and, in the absence of other disorders, have been attributed to primary mesenteric lymphadenitis. To evaluate the prevalence of enlarged MLN (short axis ≥5 mm) as detected by abdominal CT in children with a low likelihood for mesenteric lymphadenopathy. During a 14-month period, we identified all non-contrast abdominal CT examinations performed at a tertiary care pediatric hospital for evaluation of suspected or known renal stones. Two radiologists reviewed the examinations and recognized all enlarged MLN, measured the short-axis diameter, and noted the quadrant location. Sixty-one children were identified who met entry criteria; mean age was 10.7 years (range 1.1-17.3 years). Enlarged MLN were found in 33 (54%) of the 61 children; the largest enlarged MLN was most frequently in the right lower quadrant (RLQ) (29 of 33, 88%). Seventeen of the 61 children (28%) had three or more enlarged MLN; all were in the RLQ. The largest short-axis diameter measured was 10 mm. Summary: MLN with a short-axis diameter of >5-10 mm are commonly found on abdominal CT examination of children with a low likelihood for mesenteric lymphadenopathy and should be considered a non-specific finding. A short-axis diameter of 8 mm might better define the upper limit of normal mesenteric lymph node size in children. (orig.)

  13. The leak detection and location system design of petroleum pipeline

    International Nuclear Information System (INIS)

    Liu Lixia

    2011-01-01

    In order to improve the sensibility and location precision of petroleum pipeline leak with traditional negative pressure wave detection, a multi-point distributed detection and location monitoring system composed of detection nodes along pipeline, monitoring sub-stations and pressure monitoring center was designed using C/S structure. The detection node gets the pressure signal in pipeline, and sends it to monitoring center through CPRS network that achieves online monitoring for the whole pipeline in real time. The received data was analyzed and processed with multi-point distributed negative pressure wave detection and correlation analysis method. The system can rapidly detect the leak point in pipeline timely and locate accurately to avoid enormous economic loss and environment pollutions accidents. (author)

  14. Prediction of Non-sentinel Node Status in Patients with Melanoma and Positive Sentinel Node Biopsy: An Italian Melanoma Intergroup (IMI) Study.

    Science.gov (United States)

    Rossi, Carlo Riccardo; Mocellin, Simone; Campana, Luca Giovanni; Borgognoni, Lorenzo; Sestini, Serena; Giudice, Giuseppe; Caracò, Corrado; Cordova, Adriana; Solari, Nicola; Piazzalunga, Dario; Carcoforo, Paolo; Quaglino, Pietro; Caliendo, Virginia; Ribero, Simone

    2018-01-01

    Approximately 20% of melanoma patients harbor metastases in non-sentinel nodes (NSNs) after a positive sentinel node biopsy (SNB), and recent evidence questions the therapeutic benefit of completion lymph node dissection (CLND). We built a nomogram for prediction of NSN status in melanoma patients with positive SNB. Data on anthropometric and clinicopathological features of patients with cutaneous melanoma who underwent CLND after a positive SNB were collected from nine Italian centers. Multivariate logistic regression was utilized to identify predictors of NSN status in a training set, while model efficiency was validated in a validation set. Data were available for 1220 patients treated from 2000 through 2016. In the training set (n = 810), the risk of NSN involvement was higher when (1) the primary melanoma is thicker or (2) sited in the trunk/head and neck; (3) fewer nodes are excised and (4) more nodes are involved; and (5) the lymph node metastasis is larger or (6) is deeply located. The model showed high discrimination (area under the receiver operating characteristic curve 0.74, 95% confidence interval [CI] 0.70-0.79) and calibration (Brier score 0.16, 95% CI 0.15-0.17) performance in the validation set (n = 410). The nomogram including these six clinicopathological variables performed significantly better than five other previously published models in terms of both discrimination and calibration. Our nomogram could be useful for follow-up personalization in clinical practice, and for patient risk stratification while conducting clinical trials or analyzing their results.

  15. Comparison of 99mTc-MIBI scanning and sentinel node biopsy in the detection of occult melanoma lymph node metastases

    International Nuclear Information System (INIS)

    Alonso, O.; Lago, G.; Lopes de Amorim, M.C.; Juri, C.; Larre Borges, A.; Martinez, M.; De Boni, D.; Espasandin, J.; Priario, J.

    2002-01-01

    Aim: Sentinel node biopsy (SNB) is a highly accurate technique for detecting occult metastatic disease in the regional lymph nodes. Our group has reported that 99m Tc-MIBI scintigraphy is an imaging technique that can detect clinically undetectable metastases. This prospective study shows preliminary results on the comparison of both techniques for the detection of lymph node invasion. Material and Methods: Twenty-two consecutive patients (15 women, 7 men; mean age, 55 years) with primary melanoma > 1.0 mm thick were enrolled (mean 2.6 mm). Patients underwent 99m Tc-MIBI scintigraphy of regional lymph nodes 1-2 weeks before surgery, acquiring 10-minute planar images with a LFOV gamma camera. A preoperative lymphoscintigraphy using 99m Tc-colloidal (Re) sulphide was performed the day before surgery, using a dose of 74-93 MBq. Radio guided SNB was performed with a hand-held gamma probe. Lymph nodes were examined histologically and immunostained for S-100 and HMB-45. Results: The sentinel node (SN) was identified in 21/22 patients. An average of 1.6 SN/lesion were harvested from melanomas located in the following regions: head and neck (n=3), trunk (n=6), extremities (n=12). All patients with negative SN (n=11) were also negative with MIBI. In 10 cases the SN demonstrated metastatic involvement, whereas 99m Tc-MIBI was positive in 8 of them (80%). In cases with positive SN/negative 99m Tc-MIBI, the pathology report revealed micro metastatic disease. Conclusion: These preliminary results suggest that 99m Tc-MIBI scanning has the potential of selecting a group of patients who might benefit from a selective complete lymphadenectomy

  16. Earthquake location in island arcs

    Science.gov (United States)

    Engdahl, E.R.; Dewey, J.W.; Fujita, K.

    1982-01-01

    A comprehensive data set of selected teleseismic P-wave arrivals and local-network P- and S-wave arrivals from large earthquakes occurring at all depths within a small section of the central Aleutians is used to examine the general problem of earthquake location in island arcs. Reference hypocenters for this special data set are determined for shallow earthquakes from local-network data and for deep earthquakes from combined local and teleseismic data by joint inversion for structure and location. The high-velocity lithospheric slab beneath the central Aleutians may displace hypocenters that are located using spherically symmetric Earth models; the amount of displacement depends on the position of the earthquakes with respect to the slab and on whether local or teleseismic data are used to locate the earthquakes. Hypocenters for trench and intermediate-depth events appear to be minimally biased by the effects of slab structure on rays to teleseismic stations. However, locations of intermediate-depth events based on only local data are systematically displaced southwards, the magnitude of the displacement being proportional to depth. Shallow-focus events along the main thrust zone, although well located using only local-network data, are severely shifted northwards and deeper, with displacements as large as 50 km, by slab effects on teleseismic travel times. Hypocenters determined by a method that utilizes seismic ray tracing through a three-dimensional velocity model of the subduction zone, derived by thermal modeling, are compared to results obtained by the method of joint hypocenter determination (JHD) that formally assumes a laterally homogeneous velocity model over the source region and treats all raypath anomalies as constant station corrections to the travel-time curve. The ray-tracing method has the theoretical advantage that it accounts for variations in travel-time anomalies within a group of events distributed over a sizable region of a dipping, high

  17. A bio-inspired methodology of identifying influential nodes in complex networks.

    Directory of Open Access Journals (Sweden)

    Cai Gao

    Full Text Available How to identify influential nodes is a key issue in complex networks. The degree centrality is simple, but is incapable to reflect the global characteristics of networks. Betweenness centrality and closeness centrality do not consider the location of nodes in the networks, and semi-local centrality, leaderRank and pageRank approaches can be only applied in unweighted networks. In this paper, a bio-inspired centrality measure model is proposed, which combines the Physarum centrality with the K-shell index obtained by K-shell decomposition analysis, to identify influential nodes in weighted networks. Then, we use the Susceptible-Infected (SI model to evaluate the performance. Examples and applications are given to demonstrate the adaptivity and efficiency of the proposed method. In addition, the results are compared with existing methods.

  18. Finding influential nodes for integration in brain networks using optimal percolation theory.

    Science.gov (United States)

    Del Ferraro, Gino; Moreno, Andrea; Min, Byungjoon; Morone, Flaviano; Pérez-Ramírez, Úrsula; Pérez-Cervera, Laura; Parra, Lucas C; Holodny, Andrei; Canals, Santiago; Makse, Hernán A

    2018-06-11

    Global integration of information in the brain results from complex interactions of segregated brain networks. Identifying the most influential neuronal populations that efficiently bind these networks is a fundamental problem of systems neuroscience. Here, we apply optimal percolation theory and pharmacogenetic interventions in vivo to predict and subsequently target nodes that are essential for global integration of a memory network in rodents. The theory predicts that integration in the memory network is mediated by a set of low-degree nodes located in the nucleus accumbens. This result is confirmed with pharmacogenetic inactivation of the nucleus accumbens, which eliminates the formation of the memory network, while inactivations of other brain areas leave the network intact. Thus, optimal percolation theory predicts essential nodes in brain networks. This could be used to identify targets of interventions to modulate brain function.

  19. LPTA: Location Predictive and Time Adaptive Data Gathering Scheme with Mobile Sink for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Chuan Zhu

    2014-01-01

    Full Text Available This paper exploits sink mobility to prolong the lifetime of sensor networks while maintaining the data transmission delay relatively low. A location predictive and time adaptive data gathering scheme is proposed. In this paper, we introduce a sink location prediction principle based on loose time synchronization and deduce the time-location formulas of the mobile sink. According to local clocks and the time-location formulas of the mobile sink, nodes in the network are able to calculate the current location of the mobile sink accurately and route data packets timely toward the mobile sink by multihop relay. Considering that data packets generating from different areas may be different greatly, an adaptive dwelling time adjustment method is also proposed to balance energy consumption among nodes in the network. Simulation results show that our data gathering scheme enables data routing with less data transmission time delay and balance energy consumption among nodes.

  20. LPTA: location predictive and time adaptive data gathering scheme with mobile sink for wireless sensor networks.

    Science.gov (United States)

    Zhu, Chuan; Wang, Yao; Han, Guangjie; Rodrigues, Joel J P C; Lloret, Jaime

    2014-01-01

    This paper exploits sink mobility to prolong the lifetime of sensor networks while maintaining the data transmission delay relatively low. A location predictive and time adaptive data gathering scheme is proposed. In this paper, we introduce a sink location prediction principle based on loose time synchronization and deduce the time-location formulas of the mobile sink. According to local clocks and the time-location formulas of the mobile sink, nodes in the network are able to calculate the current location of the mobile sink accurately and route data packets timely toward the mobile sink by multihop relay. Considering that data packets generating from different areas may be different greatly, an adaptive dwelling time adjustment method is also proposed to balance energy consumption among nodes in the network. Simulation results show that our data gathering scheme enables data routing with less data transmission time delay and balance energy consumption among nodes.