3D Point Cloud Reconstruction from Single Plenoptic Image

Directory of Open Access Journals (Sweden)

F. Murgia

2016-06-01

Full Text Available Novel plenoptic cameras sample the light field crossing the main camera lens. The information available in a plenoptic image must be processed, in order to create the depth map of the scene from a single camera shot. In this paper a novel algorithm, for the reconstruction of 3D point cloud of the scene from a single plenoptic image, taken with a consumer plenoptic camera, is proposed. Experimental analysis is conducted on several test images, and results are compared with state of the art methodologies. The results are very promising, as the quality of the 3D point cloud from plenoptic image, is comparable with the quality obtained with current non-plenoptic methodologies, that necessitate more than one image.

Detection of kinetic change points in piece-wise linear single molecule motion

Science.gov (United States)

Hill, Flynn R.; van Oijen, Antoine M.; Duderstadt, Karl E.

2018-03-01

Single-molecule approaches present a powerful way to obtain detailed kinetic information at the molecular level. However, the identification of small rate changes is often hindered by the considerable noise present in such single-molecule kinetic data. We present a general method to detect such kinetic change points in trajectories of motion of processive single molecules having Gaussian noise, with a minimum number of parameters and without the need of an assumed kinetic model beyond piece-wise linearity of motion. Kinetic change points are detected using a likelihood ratio test in which the probability of no change is compared to the probability of a change occurring, given the experimental noise. A predetermined confidence interval minimizes the occurrence of false detections. Applying the method recursively to all sub-regions of a single molecule trajectory ensures that all kinetic change points are located. The algorithm presented allows rigorous and quantitative determination of kinetic change points in noisy single molecule observations without the need for filtering or binning, which reduce temporal resolution and obscure dynamics. The statistical framework for the approach and implementation details are discussed. The detection power of the algorithm is assessed using simulations with both single kinetic changes and multiple kinetic changes that typically arise in observations of single-molecule DNA-replication reactions. Implementations of the algorithm are provided in ImageJ plugin format written in Java and in the Julia language for numeric computing, with accompanying Jupyter Notebooks to allow reproduction of the analysis presented here.

Transition at the deliquesce point in single salts

DEFF Research Database (Denmark)

Rörig-Dalgaard, Inge

2014-01-01

Background: Deliquesce points for single salts are in general considered to occur at a specific relative humidity and are also shown as such in phase diagrams. For this reason, salts are used for calibration purpose. According to Gibbs phase rule, the crystalline solid and the saturated solution...... the increasing numbers of thin film water till 20 mbar at 25˚C whereas the deliquescence point is at 24 mbar. These results suggest a stepwise change in the state of the salt. During preparation to salt calibration tests (in a Dynamic Vapour Sorption equipment (DVS)) the author noticed that some single salts...... have a very sudden and accurate change in salt state whereas another salt changed inaccurate as was noticed with NaCl (seen in more than 10 salt preparations). In the present work, the inaccurate transition between the solid NaCl to NaCl in solution was investigated with a cooling stage (CS) in an ESEM...

[Effect of manual acupuncture stimulation of "Zusanli" (ST 36) on gastric motility, and SP and motilin activities in gastric antrum and nucleus raphe magnus in gastric hyperactivity and hypoactivity rats].

Science.gov (United States)

Yan, Chun-Chuan; Peng, Yan; Lin, Ya-Ping; Yi, Shou-Xiang; Chen, Ping; Hou, Yan-Ling; Shi, Dong-Mei

2013-10-01

To observe the changes of gastric motility and levels of substance P (SP) and motilin (MTL) in the gastric antrum and Nucleus Raphe Magnus (NRM) after manual acupuncture stimulation of "Zusanli" (ST 36) in gastric hyperactivity and hypoactivity rats, so as to analyze the role of NRM in acupuncture mediated adjustment of gastric motility. Fifty SD rats were randomly and equally divided into control, gastric hyperactivity (G-Hypera) model, gastric hypoactivity (G-Hypoa) model, acupuncture + G-Hypera and acupuncture + G-Hypoa groups (10 rats/group). G-Hypera model was established by intravenous (tail vein) injection of Maxolon (0.5 mL/200 g) and G-Hypoa model established by intravenous injection of Atropin (0.5 mL/200 g), respectively. After insertion of acupuncture needles into bilateral "Zusanli" (ST 36), the needles were repeatedly manipulated at a frequency of about 2 Hz for 5 min. The intragastric pressure was recorded and analyzed using a physiological signal analysis system. The SP and MTL contents of gastric antrum were measured by ELISA, and SP and MTL immunoactivity of NRM was determined by immunohistochemistry. In gastric hyperactivity rats, compared with the control group, the intragastric pressure (not systolic frequency), SP and MTL contents in the gastric antrum and MTL immunoactivity of NRM were significantly increased (P effect on gastric motility, which is closely associated with its functions in regulating gastric SP and MTL level and the expression of MTL and SP in the NRM of brainstem.

[Effect of Electroacupuncture Stimulation of "Guanyuan" (CV 4) and "Zusanli" (ST 36) on Spleen Lymphocytes Treg/Th 17 Immune Balance in Ulcerative Colitis Mice].

Science.gov (United States)

Wang, Cheng-yu-lin; Zeng, Lin-lan; Geng, Yu; Wang, Xiang; Zhang, He-jiao; Yang, Hui; Wu, Qiao- feng; Yu, Shu-guang

2016-02-01

To observe the effect of electroacupuncture (EA) intervention on spleen T-helper 17 (Th 17) and regulatory T (Treg) cell levels in mice with ulcerative colitis (UC), so as to reveal its mechanisms underlying improvement of UC. METHODS Kunming mice were randomized into control, UC model and EA groups, with 8 mice in each group. The UC model was established by giving the mice with 3% Dextran Sulfate Sodium (DSS) for 5 days. EA (15 Hz/25 Hz, 0.1-0.2 mA) was applied at "Guanyuan" (CV 4) and bilateral "Zusanli" (ST 36, used alternatively) for 10 min, once a day for 5 days. The animals' disease activity index [DAl, = (body weight index score + stool score + bleeding score)/3; 0-4 points] were calculated. The pathological changes of colon tissues were observed by light microscopy after H. E. stain, and spleen Treg (CD⁴⁺ CD²⁵⁺ Foxp³⁺ Treg) and Th 17 (CD³⁺ CD⁸⁺ IL-17⁺ Th 17) lymphocyte levels were determined by flow cytometry. Compared to the control group, the DAl score and the ratio of Th 17/CD⁸⁺ T cells were significantly increased, while the ratio of Treg/CD⁴⁺ T cells obviously decreased in the model group (P Th 17/CD⁸⁺ T cells and the decreased Treg/CD⁴⁺ T cells were reversed (P Th 17 lymphocytes.

Comparison of Single-Point and Continuous Sampling Methods for Estimating Residential Indoor Temperature and Humidity.

Science.gov (United States)

Johnston, James D; Magnusson, Brianna M; Eggett, Dennis; Collingwood, Scott C; Bernhardt, Scott A

2015-01-01

Residential temperature and humidity are associated with multiple health effects. Studies commonly use single-point measures to estimate indoor temperature and humidity exposures, but there is little evidence to support this sampling strategy. This study evaluated the relationship between single-point and continuous monitoring of air temperature, apparent temperature, relative humidity, and absolute humidity over four exposure intervals (5-min, 30-min, 24-hr, and 12-days) in 9 northern Utah homes, from March-June 2012. Three homes were sampled twice, for a total of 12 observation periods. Continuous data-logged sampling was conducted in homes for 2-3 wks, and simultaneous single-point measures (n = 114) were collected using handheld thermo-hygrometers. Time-centered single-point measures were moderately correlated with short-term (30-min) data logger mean air temperature (r = 0.76, β = 0.74), apparent temperature (r = 0.79, β = 0.79), relative humidity (r = 0.70, β = 0.63), and absolute humidity (r = 0.80, β = 0.80). Data logger 12-day means were also moderately correlated with single-point air temperature (r = 0.64, β = 0.43) and apparent temperature (r = 0.64, β = 0.44), but were weakly correlated with single-point relative humidity (r = 0.53, β = 0.35) and absolute humidity (r = 0.52, β = 0.39). Of the single-point RH measures, 59 (51.8%) deviated more than ±5%, 21 (18.4%) deviated more than ±10%, and 6 (5.3%) deviated more than ±15% from data logger 12-day means. Where continuous indoor monitoring is not feasible, single-point sampling strategies should include multiple measures collected at prescribed time points based on local conditions.

Neuronal Activity Stimulated by Liquid Substrates Injection at Zusanli (ST36 Acupoint: The Possible Mechanism of Aquapuncture

Directory of Open Access Journals (Sweden)

Chun-Yen Chen

2014-01-01

Full Text Available Aquapuncture is a modified acupuncture technique and it is generally accepted that it has a greater therapeutic effect than acupuncture because of the combination of the acupoint stimulation and the pharmacological effect of the drugs. However, to date, the mechanisms underlying the effects of aquapuncture remain unclear. We hypothesized that both the change in the local spatial configuration and the substrate stimulation of aquapuncture would activate neuronal signaling. Thus, bee venom, normal saline, and vitamins B1 and B12 were injected into a Zusanli (ST36 acupoint as substrate of aquapuncture, whereas a dry needle was inserted into ST36 as a control. After aquapuncture, activated neurons expressing Fos protein were mainly observed in the dorsal horn of the spinal cord in lumbar segments L3–5, with the distribution nearly identical among all groups. However, the bee venom injection induced significantly more Fos-expressing neurons than the other substrates. Based on these data, we suggest that changes in the spatial configuration of the acupoint activate neuronal signaling and that bee venom may further strengthen this neuronal activity. In conclusion, the mechanisms for the effects of aquapuncture appear to be the spatial configuration changes occurring within the acupoint and the ability of injected substrates to stimulate neuronal activity.

ESTUDIO DEL EFECTO COMPARATIVO SOBRE EL DOLOR Y LAS PARESTESIAS EN LA NEUROPATIA DIABETICA TRATADA CON ACUPUNTURA [TAICHONG (H 3), SANYINJIAO (B 6), ZUSANLI (E 36) Y XUEHAI (B 10) VS. MISMA FORMULA MAS BENSHEN (VB 13)

OpenAIRE

GARCIA SALGADO, LEMUEL

2010-01-01

LA NEUROPATIA DIABETICA, ES UNA ENFERMEDAD QUE SE PRESENTA COMO COMPLICACION DE LA DIABETES MELLITUS, RESPONSABLE DEL DOLOR Y PARESTESIAS (ALTERACIONES SOMATO SENSITIVAS) POR FALTA DE CIRCULACION AFECTANDO PRINCIPALMENTE LAS TERMINACIONES NERVIOSAS LIBRES EN LAS PARTES DISTALES DEL CUERPO DE LOS ENFERMOS. EL PRESENTE TRABAJO DE INVESTIGACION, TIENE COMO OBJETIVO COMPARAR EL EFECTO ANALGESICO EN EL TRATAMIENTO DE LA NEUROPATIA DIABETICA UTILIZANDO PUNTOS DE ACUPUNTURA [ZUSANLI (E 36), SANYINJ...

Real-time multi-GNSS single-frequency precise point positioning

NARCIS (Netherlands)

de Bakker, P.F.; Tiberius, C.C.J.M.

2017-01-01

Precise Point Positioning (PPP) is a popular Global Positioning System (GPS) processing strategy, thanks to its high precision without requiring additional GPS infrastructure. Single-Frequency PPP (SF-PPP) takes this one step further by no longer relying on expensive dual-frequency GPS receivers,

Acupuncture inhibits cue-induced heroin craving and brain activation.

Science.gov (United States)

Cai, Xinghui; Song, Xiaoge; Li, Chuanfu; Xu, Chunsheng; Li, Xiliang; Lu, Qi

2012-11-25

Previous research using functional MRI has shown that specific brain regions associated with drug dependence and cue-elicited heroin craving are activated by environmental cues. Craving is an important trigger of heroin relapse, and acupuncture may inhibit craving. In this study, we performed functional MRI in heroin addicts and control subjects. We compared differences in brain activation between the two groups during heroin cue exposure, heroin cue exposure plus acupuncture at the Zusanli point (ST36) without twirling of the needle, and heroin cue exposure plus acupuncture at the Zusanli point with twirling of the needle. Heroin cue exposure elicited significant activation in craving-related brain regions mainly in the frontal lobes and callosal gyri. Acupuncture without twirling did not significantly affect the range of brain activation induced by heroin cue exposure, but significantly changed the extent of the activation in the heroin addicts group. Acupuncture at the Zusanli point with twirling of the needle significantly decreased both the range and extent of activation induced by heroin cue exposure compared with heroin cue exposure plus acupuncture without twirling of the needle. These experimental findings indicate that presentation of heroin cues can induce activation in craving-related brain regions, which are involved in reward, learning and memory, cognition and emotion. Acupuncture at the Zusanli point can rapidly suppress the activation of specific brain regions related to craving, supporting its potential as an intervention for drug craving.

Revisiting the fundamentals of single point incremental forming by

DEFF Research Database (Denmark)

Silva, Beatriz; Skjødt, Martin; Martins, Paulo A.F.

2008-01-01

Knowledge of the physics behind the fracture of material at the transition between the inclined wall and the corner radius of the sheet is of great importance for understanding the fundamentals of single point incremental forming (SPIF). How the material fractures, what is the state of strain...

The validity of multiphase DNS initialized on the basis of single--point statistics

Science.gov (United States)

Subramaniam, Shankar

1999-11-01

A study of the point--process statistical representation of a spray reveals that single--point statistical information contained in the droplet distribution function (ddf) is related to a sequence of single surrogate--droplet pdf's, which are in general different from the physical single--droplet pdf's. The results of this study have important consequences for the initialization and evolution of direct numerical simulations (DNS) of multiphase flows, which are usually initialized on the basis of single--point statistics such as the average number density in physical space. If multiphase DNS are initialized in this way, this implies that even the initial representation contains certain implicit assumptions concerning the complete ensemble of realizations, which are invalid for general multiphase flows. Also the evolution of a DNS initialized in this manner is shown to be valid only if an as yet unproven commutation hypothesis holds true. Therefore, it is questionable to what extent DNS that are initialized in this manner constitute a direct simulation of the physical droplets.

Inhibitory Effects of 658 nm Laser Irradiation on Skin Temperature in Anesthetized Rats: Preliminary Results from a Controlled Study

Directory of Open Access Journals (Sweden)

Daniela Litscher

2014-01-01

Full Text Available Red laser light stimulation can have many physiological effects. The goal of this animal experimental study was to investigate how red laser stimulation influences the temperature of anesthetized rats at different acupuncture points and nonacupoints. For that reason 12 adult male Wistar Han rats (300–380 g were investigated. Six anesthetized rats underwent red laser stimulation (wavelength 658 nm, output power 40 mW, diameter 500 µm, and duration 10 min at the Baihui (GV20 acupoint, the Zusanli acupoint (ST36, bilateral, and a control point on the forelimb. The other six rats underwent the same procedure; however, the laser remained switched off. Significant decreases in temperature were found at the acupoints Baihui, Zusanli left, and Zusanli right. In addition there was no significant temperature effect at a control point. During placebo laser irradiation (deactivated laser there were also significant temperature changes. The mechanism underlying the results is currently unknown, but brain stimulation (via laser or mechanical pressure and mainly direct central mechanisms may be responsible for the local and peripheral temperature decrease.

The Point Zoro Symmetric Single-Step Procedure for Simultaneous Estimation of Polynomial Zeros

Directory of Open Access Journals (Sweden)

Mansor Monsi

2012-01-01

Full Text Available The point symmetric single step procedure PSS1 has R-order of convergence at least 3. This procedure is modified by adding another single-step, which is the third step in PSS1. This modified procedure is called the point zoro symmetric single-step PZSS1. It is proven that the R-order of convergence of PZSS1 is at least 4 which is higher than the R-order of convergence of PT1, PS1, and PSS1. Hence, computational time is reduced since this procedure is more efficient for bounding simple zeros simultaneously.

Common fixed points of single-valued and multivalued maps

Directory of Open Access Journals (Sweden)

Yicheng Liu

2005-01-01

Full Text Available We define a new property which contains the property (EA for a hybrid pair of single- and multivalued maps and give some new common fixed point theorems under hybrid contractive conditions. Our results extend previous ones. As an application, we give a partial answer to the problem raised by Singh and Mishra.

[Professor WU Zhongchao's experience in the treatment of bi syndrome with fire needling therapy at lower he-sea points].

Science.gov (United States)

Zhou, Yu; Chen, Zhongjie; Liu, Chun; Wang, Bing; Zhang, Ning; Li, Caifen; Xie, Qian

2016-07-12

Bi syndrome is classified into five categories. Based on the syndrome differentiation of meridians and collaterals and zangfu theories, Professor WU Zhongchao proposed the fire needling therapy at the lower he -sea points for five types of bi syndromes. Professor WU stresses on the flexible application of fire needling therapy for bi syndrome at the lower he -sea points and innovated the unique five techniques of fire needling therapy, named lifting and threating needle of small amplitude at the lower he -sea points, the stimulation along the relevant meri-dians before fire needling, detecting the sensitive sites by gentle pressing the relevant lower he -sea points, combining the movement of affected upper limb or joint during fire needling, or combining with contralateral needling technique, and controlling the depth of fire needling based on the duration of sickness and depth of affected site. He pointed out that Shangjuxu (ST 37) is for skin bi syndrome, Zusanli (ST 36) for muscle bi syndrome, Yanglingquan (GB 34) for tendon bi syndrome, Weizhong (BL 40) for bone bi syndrome and Xiajuxu (ST 39) for vessel bi syndrome.

Quenching points of dimeric single-molecule magnets: Exchange interaction effects

International Nuclear Information System (INIS)

Florez, J.M.; Nunez, Alvaro S.; Vargas, P.

2010-01-01

We study the quenched energy-splitting (Δ E ) of a single-molecule magnet (SMM) conformed by two exchange coupled giant-spins. An assessment of two nontrivial characteristics of this quenching is presented: (i) The quenching-points of a strongly exchange-coupled dimer differ from the ones of their respective giant-spin modeled SMM and such a difference can be well described by using the Solari-Kochetov extra phase; (ii) the dependence on the exchange coupling of the magnetic field values at the quenching-points when Δ E passes from monomeric to dimeric behavior. The physics behind these exchange-modified points, their relation with the Δ E -oscillations experimentally obtained by the Landau-Zener method and with the diabolical-plane of a SMM, is discussed.

Quenching points of dimeric single-molecule magnets: Exchange interaction effects

Energy Technology Data Exchange (ETDEWEB)

Florez, J.M., E-mail: juanmanuel.florez@alumnos.usm.c [Departamento de Fisica, Universidad Tecnica Federico Santa Maria, P.O. Box 110-V, Valparaiso (Chile); Nunez, Alvaro S., E-mail: alnunez@dfi.uchile.c [Departamento de Fisica, Facultad de Ciencias Fisicas y Matematicas, Universidad de Chile, Casilla 487-3, Santiago (Chile); Vargas, P., E-mail: patricio.vargas@usm.c [Departamento de Fisica, Universidad Tecnica Federico Santa Maria, P.O. Box 110-V, Valparaiso (Chile)

2010-11-15

We study the quenched energy-splitting ({Delta}{sub E}) of a single-molecule magnet (SMM) conformed by two exchange coupled giant-spins. An assessment of two nontrivial characteristics of this quenching is presented: (i) The quenching-points of a strongly exchange-coupled dimer differ from the ones of their respective giant-spin modeled SMM and such a difference can be well described by using the Solari-Kochetov extra phase; (ii) the dependence on the exchange coupling of the magnetic field values at the quenching-points when {Delta}{sub E} passes from monomeric to dimeric behavior. The physics behind these exchange-modified points, their relation with the {Delta}{sub E}-oscillations experimentally obtained by the Landau-Zener method and with the diabolical-plane of a SMM, is discussed.

Single point incremental forming of tailored blanks produced by friction stir welding

DEFF Research Database (Denmark)

Silva, M.B.; Skjødt, Martin; Vilaca, P.

2009-01-01

fromthe rotating single point-forming tool. Formability of the tailor welded blanks (TWB) is evaluated by means of benchmark tests carried out on truncated conical and pyramidal shapes and results are compared with similar tests performed on conventional reference blanks of the same material. Results show......This paper is focused on the single point incremental forming (SPIF) of tailored welded blanks produced by friction stirwelding (FSW). Special emphasis is placed on the know-how for producing the tailored blanks and on the utilization of innovative forming strategies to protect thewelding joint...... that the combination of SPIF with tailored welded blanks produced by FSW seems promising in the manufacture of complex sheet metal parts with high depths....

Effectiveness of Acupressure at the Zusanli (ST-36) Acupoint as a Comfortable Treatment for Diabetes Mellitus: A Pilot Study in Indonesia.

Science.gov (United States)

Fitrullah; Rousdy, Addison

2017-04-01

Diabetes mellitus is a dangerous disease worldwide. Indonesia has 10 million diabetic and 17.9 million prediabetic citizens. Unfortunately, less than half of these diabetic individuals are aware of their conditions and less than 1% of those receiving medical treatment achieve their healing targets. Because acupressure is believed to be an effective treatment without the use of drugs, in this study we investigated acupressure as a comfortable and effective way of treating patients with diabetes mellitus. This pilot study involved 30 participants who were split into two groups: 15 each in the experimental and the control groups. The experimental group underwent acupressure at the Zusanli (ST-36) acupoint for 30 minutes per visit for 11 weeks, whereas the control group continued their regular treatment; participants in both groups had their blood glucose randomly checked weekly. Data were analyzed using the Generalized Estimating Equation model; the result showed that the two groups were significantly different (p=0.331 > α=0.05; mean difference=99.14; Bonferroni sig. p=0.000 diabetes. Copyright © 2017 Medical Association of Pharmacopuncture Institute. Published by Elsevier B.V. All rights reserved.

FUNDAMENTAL ASPECTS OF EPISODIC ACCRETION CHEMISTRY EXPLORED WITH SINGLE-POINT MODELS

International Nuclear Information System (INIS)

Visser, Ruud; Bergin, Edwin A.

2012-01-01

We explore a set of single-point chemical models to study the fundamental chemical aspects of episodic accretion in low-mass embedded protostars. Our goal is twofold: (1) to understand how the repeated heating and cooling of the envelope affects the abundances of CO and related species; and (2) to identify chemical tracers that can be used as a novel probe of the timescales and other physical aspects of episodic accretion. We develop a set of single-point models that serve as a general prescription for how the chemical composition of a protostellar envelope is altered by episodic accretion. The main effect of each accretion burst is to drive CO ice off the grains in part of the envelope. The duration of the subsequent quiescent stage (before the next burst hits) is similar to or shorter than the freeze-out timescale of CO, allowing the chemical effects of a burst to linger long after the burst has ended. We predict that the resulting excess of gas-phase CO can be observed with single-dish or interferometer facilities as evidence of an accretion burst in the past 10 3 -10 4 yr.

A numerical analysis on forming limits during spiral and concentric single point incremental forming

Science.gov (United States)

Gipiela, M. L.; Amauri, V.; Nikhare, C.; Marcondes, P. V. P.

2017-01-01

Sheet metal forming is one of the major manufacturing industries, which are building numerous parts for aerospace, automotive and medical industry. Due to the high demand in vehicle industry and environmental regulations on less fuel consumption on other hand, researchers are innovating new methods to build these parts with energy efficient sheet metal forming process instead of conventionally used punch and die to form the parts to achieve the lightweight parts. One of the most recognized manufacturing process in this category is Single Point Incremental Forming (SPIF). SPIF is the die-less sheet metal forming process in which the single point tool incrementally forces any single point of sheet metal at any process time to plastic deformation zone. In the present work, finite element method (FEM) is applied to analyze the forming limits of high strength low alloy steel formed by single point incremental forming (SPIF) by spiral and concentric tool path. SPIF numerical simulations were model with 24 and 29 mm cup depth, and the results were compare with Nakajima results obtained by experiments and FEM. It was found that the cup formed with Nakajima tool failed at 24 mm while cups formed by SPIF surpassed the limit for both depths with both profiles. It was also notice that the strain achieved in concentric profile are lower than that in spiral profile.

Substructuring in the implicit simulation of single point incremental sheet forming

NARCIS (Netherlands)

Hadoush, A.; van den Boogaard, Antonius H.

2009-01-01

This paper presents a direct substructuring method to reduce the computing time of implicit simulations of single point incremental forming (SPIF). Substructuring is used to divide the finite element (FE) mesh into several non-overlapping parts. Based on the hypothesis that plastic deformation is

Single Point Incremental Forming using a Dummy Sheet

DEFF Research Database (Denmark)

Skjødt, Martin; Silva, Beatriz; Bay, Niels

2007-01-01

A new version of single point incremental forming (SPIF) is presented. This version includes a dummy sheet on top of the work piece, thus forming two sheets instead of one. The dummy sheet, which is in contact with the rotating tool pin, is discarded after forming. The new set-up influences....... The possible influence of friction between the two sheets is furthermore investigated. The results show that the use of a dummy sheet reduces wear of the work piece to almost zero, but also causes a decrease in formability. Bulging of the planar sides of the pyramid is reduced and surface roughness...

Securing Single Points of Compromise (SPoC)

Energy Technology Data Exchange (ETDEWEB)

Belangia, David Warren [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2015-06-25

Securing the Single Points of Compromise that provide central services to the institution’s environment is paramount to success when trying to protect the business. (Fisk, 2014) Time Based Security mandates protection (erecting and ensuring effective controls) that last longer than the time to detect and react to a compromise. When enterprise protections fail, providing additional layered controls for these central services provides more time to detect and react. While guidance is readily available for securing the individual critical asset, protecting these assets as a group is not often discussed. Using best business practices to protect these resources as individual assets while leveraging holistic defenses for the group increases the opportunity to maximize protection time, allowing detection and reaction time for the SPoCs that is commensurate with the inherent risk of these centralized services.

Mechanism of DNA–binding loss upon single-point mutation in p53

Indian Academy of Sciences (India)

PRAKASH KUMAR

loss in protein−DNA binding affinity and specificity upon single point ..... we computed the root–mean–square–deviations (RMSDs) of each residue's ...... Petsko G and Ringe D 1984 Fluctuations in protein structure from. X-ray diffraction; Annu.

Design of an omnidirectional single-point photodetector for large-scale spatial coordinate measurement

Science.gov (United States)

Xie, Hongbo; Mao, Chensheng; Ren, Yongjie; Zhu, Jigui; Wang, Chao; Yang, Lei

2017-10-01

In high precision and large-scale coordinate measurement, one commonly used approach to determine the coordinate of a target point is utilizing the spatial trigonometric relationships between multiple laser transmitter stations and the target point. A light receiving device at the target point is the key element in large-scale coordinate measurement systems. To ensure high-resolution and highly sensitive spatial coordinate measurement, a high-performance and miniaturized omnidirectional single-point photodetector (OSPD) is greatly desired. We report one design of OSPD using an aspheric lens, which achieves an enhanced reception angle of -5 deg to 45 deg in vertical and 360 deg in horizontal. As the heart of our OSPD, the aspheric lens is designed in a geometric model and optimized by LightTools Software, which enables the reflection of a wide-angle incident light beam into the single-point photodiode. The performance of home-made OSPD is characterized with working distances from 1 to 13 m and further analyzed utilizing developed a geometric model. The experimental and analytic results verify that our device is highly suitable for large-scale coordinate metrology. The developed device also holds great potential in various applications such as omnidirectional vision sensor, indoor global positioning system, and optical wireless communication systems.

Evaluating Change in Behavioral Preferences: Multidimensional Scaling Single-Ideal Point Model

Science.gov (United States)

Ding, Cody

2016-01-01

The purpose of the article is to propose a multidimensional scaling single-ideal point model as a method to evaluate changes in individuals' preferences under the explicit methodological framework of behavioral preference assessment. One example is used to illustrate the approach for a clear idea of what this approach can accomplish.

Dual time point 18FDG-PET/CT versus single time point 18FDG-PET/CT for the differential diagnosis of pulmonary nodules - A meta-analysis

International Nuclear Information System (INIS)

Zhang, Li; Wang, Yinzhong; Lei, Junqiang; Tian, Jinhui; Zhai, Yanan

2013-01-01

Background: Lung cancer is one of the most common cancer types in the world. An accurate diagnosis of lung cancer is crucial for early treatment and management. Purpose: To perform a comprehensive meta-analysis to evaluate the diagnostic performance of dual time point 18F-fluorodexyglucose position emission tomography/computed tomography (FDG-PET/CT) and single time point 18FDG-PET/CT in the diagnosis of pulmonary nodules. Material and Methods: PubMed (1966-2011.11), EMBASE (1974-2011.11), Web of Science (1972-2011.11), Cochrane Library (-2011.11), and four Chinese databases; CBM (1978-2011.11), CNKI (1994-2011.11), VIP (1989-2011.11), and Wanfang Database (1994-2011.11) were searched. Summary sensitivity, summary specificity, summary diagnostic odds ratios (DOR), and summary positive likelihood ratios (LR+) and negative likelihood ratios (LR-) were obtained using Meta-Disc software. Summary receiver-operating characteristic (SROC) curves were used to evaluate the diagnostic performance of dual time point 18FDG-PET/CT and single time point 18FDG-PET/CT. Results: The inclusion criteria were fulfilled by eight articles, with a total of 415 patients and 430 pulmonary nodules. Compared with the gold standard (pathology or clinical follow-up), the summary sensitivity of dual time point 18FDG-PET/CT was 79% (95%CI, 74.0 - 84.0%), and its summary specificity was 73% (95%CI, 65.0-79.0%); the summary LR+ was 2.61 (95%CI, 1.96-3.47), and the summary LR- was 0.29 (95%CI, 0.21 - 0.41); the summary DOR was 10.25 (95%CI, 5.79 - 18.14), and the area under the SROC curve (AUC) was 0.8244. The summary sensitivity for single time point 18FDG-PET/CT was 77% (95%CI, 71.9 - 82.3%), and its summary specificity was 59% (95%CI, 50.6 - 66.2%); the summary LR+ was 1.97 (95%CI, 1.32 - 2.93), and the summary LR- was 0.37 (95%CI, 0.29 - 0.49); the summary DOR was 6.39 (95%CI, 3.39 - 12.05), and the AUC was 0.8220. Conclusion: The results indicate that dual time point 18FDG-PET/CT and single

Failure mechanisms in single-point incremental forming of metals

DEFF Research Database (Denmark)

Silva, Maria B.; Nielsen, Peter Søe; Bay, Niels

2011-01-01

The last years saw the development of two different views on how failure develops in single-point incremental forming (SPIF). Today, researchers are split between those claiming that fracture is always preceded by necking and those considering that fracture occurs with suppression of necking. Each...... on formability limits and development of fracture. The unified view conciliates the aforementioned different explanations on the role of necking in fracture and is consistent with the experimental observations that have been reported in the past years. The work is performed on aluminium AA1050-H111 sheets...

A GLOBAL REGISTRATION ALGORITHM OF THE SINGLE-CLOSED RING MULTI-STATIONS POINT CLOUD

Directory of Open Access Journals (Sweden)

R. Yang

2018-04-01

Full Text Available Aimed at the global registration problem of the single-closed ring multi-stations point cloud, a formula in order to calculate the error of rotation matrix was constructed according to the definition of error. The global registration algorithm of multi-station point cloud was derived to minimize the error of rotation matrix. And fast-computing formulas of transformation matrix with whose implementation steps and simulation experiment scheme was given. Compared three different processing schemes of multi-station point cloud, the experimental results showed that the effectiveness of the new global registration method was verified, and it could effectively complete the global registration of point cloud.

Single cell analysis of G1 check points-the relationship between the restriction point and phosphorylation of pRb

International Nuclear Information System (INIS)

Martinsson, Hanna-Stina; Starborg, Maria; Erlandsson, Fredrik; Zetterberg, Anders

2005-01-01

Single cell analysis allows high resolution investigation of temporal relationships between transition events in G 1 . It has been suggested that phosphorylation of the retinoblastoma tumor suppressor protein (pRb) is the molecular mechanism behind passage through the restriction point (R). We performed a detailed single cell study of the temporal relationship between R and pRb phosphorylation in human fibroblasts using time lapse video-microscopy combined with immunocytochemistry. Four principally different criteria for pRb phosphorylation were used, namely (i) phosphorylation of residues Ser 795 and Ser 780 (ii) degree of pRb-association with the nuclear structure, a property that is closely related with pRb phosphorylation status, (iii) release of the transcription factor E2F-1 from pRb, and (iv) accumulation of cyclin E, which is dependent on phosphorylation of pRb. The analyses of individual cells revealed that passage through R preceded phosphorylation of pRb, which occurs in a gradually increasing proportion of cells in late G 1 . Our data clearly suggest that pRb phosphorylation is not the molecular mechanism behind the passage through R. The restriction point and phosphorylation of pRb thus seem to represent two separate check point in G 1

New organophilic kaolin clays based on single-point grafted 3-aminopropyl dimethylethoxysilane.

Science.gov (United States)

Zaharia, A; Perrin, F-X; Teodorescu, M; Radu, A-L; Iordache, T-V; Florea, A-M; Donescu, D; Sarbu, A

2015-10-14

In this study, the organophilization procedure of kaolin rocks with a monofunctional ethoxysilane- 3 aminopropyl dimethyl ethoxysilane (APMS) is depicted for the first time. The two-step organophilization procedure, including dimethyl sulfoxide intercalation and APMS grafting onto the inner hydroxyl surface of kaolinite (the mineral) layers was tested for three sources of kaolin rocks (KR, KC and KD) with various morphologies and kaolinite compositions. The load of APMS in the kaolinite interlayer space was higher than that of 3-aminopropyl triethoxysilane (APTS) due to the single-point grafting nature of the organophilization reaction. A higher long-distance order of kaolinite layers with low staking was obtained for the APMS, due to a more controllable organiphilization reaction. Last but not least, the solid state (29)Si-NMR tests confirmed the single-point grafting mechanism of APMS, corroborating monodentate fixation on the kaolinite hydroxyl facets, with no contribution to the bidentate or tridentate fixation as observed for APTS.

Analysis on Single Point Vulnerabilities of Plant Control System

International Nuclear Information System (INIS)

Chi, Moon Goo; Lee, Eun Chan; Bae, Yeon Kyoung

2011-01-01

The Plant Control System (PCS) is a system that controls pumps, valves, dampers, etc. in nuclear power plants with an OPR-1000 design. When there is a failure or spurious actuation of the critical components in the PCS, it can result in unexpected plant trips or transients. From this viewpoint, single point vulnerabilities are evaluated in detail using failure mode effect analyses (FMEA) and fault tree analyses (FTA). This evaluation demonstrates that the PCS has many vulnerable components and the analysis results are provided for OPR-1000 plants for reliability improvements that can reduce their vulnerabilities

Analysis on Single Point Vulnerabilities of Plant Control System

Energy Technology Data Exchange (ETDEWEB)

Chi, Moon Goo; Lee, Eun Chan; Bae, Yeon Kyoung [Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

2011-08-15

The Plant Control System (PCS) is a system that controls pumps, valves, dampers, etc. in nuclear power plants with an OPR-1000 design. When there is a failure or spurious actuation of the critical components in the PCS, it can result in unexpected plant trips or transients. From this viewpoint, single point vulnerabilities are evaluated in detail using failure mode effect analyses (FMEA) and fault tree analyses (FTA). This evaluation demonstrates that the PCS has many vulnerable components and the analysis results are provided for OPR-1000 plants for reliability improvements that can reduce their vulnerabilities.

Strategies and limits in multi-stage single-point incremental forming

DEFF Research Database (Denmark)

Skjødt, Martin; Silva, M.B.; Martins, P. A. F.

2010-01-01

paths. The results also reveal that the sequence of multi-stage forming has a large effect on the location of strain points in the principal strain space. Strain paths are linear in the first stage and highly non-linear in the subsequent forming stages. The overall results show that the experimentally......Multi-stage single-point incremental forming (SPIF) is a state-of-the-art manufacturing process that allows small-quantity production of complex sheet metal parts with vertical walls. This paper is focused on the application of multi-stage SPIF with the objective of producing cylindrical cups......-limit curves and fracture forming-limit curves (FFLCs), numerical simulation, and experimentation, namely the evaluation of strain paths and fracture strains in actual multi-stage parts. Assessment of numerical simulation with experimentation shows good agreement between computed and measured strain and strain...

Generating and executing programs for a floating point single instruction multiple data instruction set architecture

Science.gov (United States)

Gschwind, Michael K

2013-04-16

Mechanisms for generating and executing programs for a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA) are provided. A computer program product comprising a computer recordable medium having a computer readable program recorded thereon is provided. The computer readable program, when executed on a computing device, causes the computing device to receive one or more instructions and execute the one or more instructions using logic in an execution unit of the computing device. The logic implements a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA), based on data stored in a vector register file of the computing device. The vector register file is configured to store both scalar and floating point values as vectors having a plurality of vector elements.

Single Point Adjustments: A New Definition with Examples. Acquisition Review Quarterly, Fall 2001

National Research Council Canada - National Science Library

Bachman, David

2002-01-01

.... A single point adjustment (SPA) is made when a contract's existing cost and/or schedule variances are set to zero and all the remaining work is replanned with the goal of completing the project on schedule and on budget...

Single Point Vulnerability Analysis of Automatic Seismic Trip System

International Nuclear Information System (INIS)

Oh, Seo Bin; Chung, Soon Il; Lee, Yong Suk; Choi, Byung Pil

2016-01-01

Single Point Vulnerability (SPV) analysis is a process used to identify individual equipment whose failure alone will result in a reactor trip, turbine generator failure, or power reduction of more than 50%. Automatic Seismic Trip System (ASTS) is a newly installed system to ensure the safety of plant when earthquake occurs. Since this system directly shuts down the reactor, the failure or malfunction of its system component can cause a reactor trip more frequently than other systems. Therefore, an SPV analysis of ASTS is necessary to maintain its essential performance. To analyze SPV for ASTS, failure mode and effect analysis (FMEA) and fault tree analysis (FTA) was performed. In this study, FMEA and FTA methods were performed to select SPV equipment of ASTS. D/O, D/I, A/I card, seismic sensor, and trip relay had an effect on the reactor trip but their single failure will not cause reactor trip. In conclusion, ASTS is excluded as SPV. These results can be utilized as the basis data for ways to enhance facility reliability such as design modification and improvement of preventive maintenance procedure

Single Point Vulnerability Analysis of Automatic Seismic Trip System

Energy Technology Data Exchange (ETDEWEB)

Oh, Seo Bin; Chung, Soon Il; Lee, Yong Suk [FNC Technology Co., Yongin (Korea, Republic of); Choi, Byung Pil [KHNP CRI, Daejeon (Korea, Republic of)

2016-10-15

Single Point Vulnerability (SPV) analysis is a process used to identify individual equipment whose failure alone will result in a reactor trip, turbine generator failure, or power reduction of more than 50%. Automatic Seismic Trip System (ASTS) is a newly installed system to ensure the safety of plant when earthquake occurs. Since this system directly shuts down the reactor, the failure or malfunction of its system component can cause a reactor trip more frequently than other systems. Therefore, an SPV analysis of ASTS is necessary to maintain its essential performance. To analyze SPV for ASTS, failure mode and effect analysis (FMEA) and fault tree analysis (FTA) was performed. In this study, FMEA and FTA methods were performed to select SPV equipment of ASTS. D/O, D/I, A/I card, seismic sensor, and trip relay had an effect on the reactor trip but their single failure will not cause reactor trip. In conclusion, ASTS is excluded as SPV. These results can be utilized as the basis data for ways to enhance facility reliability such as design modification and improvement of preventive maintenance procedure.

SINGLE TREE DETECTION FROM AIRBORNE LASER SCANNING DATA USING A MARKED POINT PROCESS BASED METHOD

Directory of Open Access Journals (Sweden)

J. Zhang

2013-05-01

Full Text Available Tree detection and reconstruction is of great interest in large-scale city modelling. In this paper, we present a marked point process model to detect single trees from airborne laser scanning (ALS data. We consider single trees in ALS recovered canopy height model (CHM as a realization of point process of circles. Unlike traditional marked point process, we sample the model in a constraint configuration space by making use of image process techniques. A Gibbs energy is defined on the model, containing a data term which judge the fitness of the model with respect to the data, and prior term which incorporate the prior knowledge of object layouts. We search the optimal configuration through a steepest gradient descent algorithm. The presented hybrid framework was test on three forest plots and experiments show the effectiveness of the proposed method.

Point defects in lines in single crystalline phosphorene: directional migration and tunable band gaps.

Science.gov (United States)

Li, Xiuling; Ma, Liang; Wang, Dayong; Zeng, Xiao Cheng; Wu, Xiaojun; Yang, Jinlong

2016-10-20

Extended line defects in two-dimensional (2D) materials can play an important role in modulating their electronic properties. During the experimental synthesis of 2D materials, line defects are commonly generated at grain boundaries between domains of different orientations. In this work, twelve types of line-defect structures in single crystalline phosphorene are examined by using first-principles calculations. These line defects are typically formed via migration and aggregation of intrinsic point defects, including the Stone-Wales (SW), single or double vacancy (SV or DV) defects. Our calculated results demonstrate that the migration of point defects in phosphorene is anisotropic, for instance, the lowest migration energy barriers are 1.39 (or 0.40) and 2.58 (or 0.49) eV for SW (or SV) defects in zigzag and armchair directions, respectively. The aggregation of point defects into lines is energetically favorable compared with the separated point defects in phosphorene. In particular, the axis of line defects in phosphorene is direction-selective, depending on the composed point defects. The presence of line defects effectively modulates the electronic properties of phosphorene, rendering the defect-containing phosphorene either metallic or semiconducting with a tunable band gap. Of particular interest is the fact that the SV-based line defect can behave as a metallic wire, suggesting a possibility to fabricate a circuit with subnanometer widths in the semiconducting phosphorene for nanoscale electronic application.

Self-consistent neutral point current and fields from single particle dynamics

International Nuclear Information System (INIS)

Martin, R.F. Jr.

1988-01-01

In order to begin to build a global model of the magnetotail-auroral region interaction, it is of interest to understand the role of neutral points as potential centers of particle energization in the tail. In this paper, the single particle current is calculated near a magnetic neutral point with magnetotail properties. This is balanced with the Ampere's law current producing the magnetic field to obtain the self-consistent electric field for the problem. Also calculated is the current-electric field relationship and, in the regime where this relation is linear, an effective conductivity. Results for these macroscopic quantities are surprisingly similar to the values calculated for a constant normal field current sheet geometry. Application to magnetotail modeling is discussed. 11 references

A Biomechanical Model of Single-joint Arm Movement Control Based on the Equilibrium Point Hypothesis

OpenAIRE

Masataka, SUZUKI; Yoshihiko, YAMAZAKI; Yumiko, TANIGUCHI; Department of Psychology, Kinjo Gakuin University; Department of Health and Physical Education, Nagoya Institute of Technology; College of Human Life and Environment, Kinjo Gakuin University

2003-01-01

SUZUKI,M., YAMAZAKI,Y. and TANIGUCHI,Y., A Biomechanical Model of Single-joint Arm Movement Control Based on the Equilibrium Point Hypothesis. Adv. Exerc. Sports Physiol., Vol.9, No.1 pp.7-25, 2003. According to the equilibrium point hypothesis of motor control, control action of muscles is not explicitly computed, but rather arises as a consequence of interaction among moving equilibrium point, reflex feedback and muscle mechanical properties. This approach is attractive as it obviates the n...

Point defects and magnetic properties of neutron irradiated MgO single crystal

Directory of Open Access Journals (Sweden)

Mengxiong Cao

2017-05-01

Full Text Available (100-oriented MgO single crystals were irradiated to introduce point defects with different neutron doses ranging from 1.0×1016 to 1.0×1020 cm-2. The point defect configurations were studied with X-ray diffuse scattering and UV-Vis absorption spectra. The isointensity profiles of X-ray diffuse scattering caused by the cubic and double-force point defects in MgO were theoretically calculated based on the Huang scattering theory. The magnetic properties at different temperature were measured with superconducting quantum interference device (SQUID. The reciprocal space mappings (RSMs of irradiated MgO revealed notable diffuse scattering. The UV-Vis spectra indicated the presence of O Frenkel defects in irradiated MgO. Neutron-irradiated MgO was diamagnetic at room temperature and became ferromagnetic at low temperature due to O Frenkel defects induced by neutron-irradiation.

A primary study on meridian-stretching of injected FDG using PET MPItool

International Nuclear Information System (INIS)

He Yijie; Tian Jiahe; Chen Yingmao; Yin Dayi; Zhang Jinming; Zhang Shuwen; Shao Mingzhe; Yao Shulin; Ding Weimin; Liu Zilai

2002-01-01

Objective: To show the images of tracer-stretching along the acupuncture meridian by use of PET with multipurpose imaging tool (MPItool's) fusion function. Methods: On 5 healthy volunteers, the authors measured the classical acupuncture points accurately with the biophysical measuring method. 18 F-fluorodeoxyglucose (FDG) was injected into the selected points, the others points along the same meridian were labelled with 18 F-FDG applied on the correspondent skin area of 2 . With the same body position, the transmission image and emission image was acquired respectively and fused with MPItool and its 3D display system. Results: The authors clearly showed not only the meridian-stretching images of the tracer, but also figured out the depth of the study points. The depth at SHANGJUXU point was about 3.8 cm and at ZUSANLI point was about 5,0 cm. The depths basically fit the classically documented ones of the correspondent acupuncture points. Conclusions: Using PET MPItool the authors preliminarily demonstrated that the tracer injected at the acupuncture point stretches along the correspondent meridian, and the depths of the meridian and the points (SHANGJUXU, ZUSANLI) detected are almost accordant with the classically documented ones

Single point incremental forming: Formability of PC sheets

Science.gov (United States)

Formisano, A.; Boccarusso, L.; Carrino, L.; Lambiase, F.; Minutolo, F. Memola Capece

2018-05-01

Recent research on Single Point Incremental Forming of polymers has slightly covered the possibility of expanding the materials capability window of this flexible forming process beyond metals, by demonstrating the workability of thermoplastic polymers at room temperature. Given the different behaviour of polymers compared to metals, different aspects need to be deepened to better understand the behaviour of these materials when incrementally formed. Thus, the aim of the work is to investigate the formability of incrementally formed polycarbonate thin sheets. To this end, an experimental investigation at room temperature was conducted involving formability tests; varying wall angle cone and pyramid frusta were manufactured by processing polycarbonate sheets with different thicknesses and using tools with different diameters, in order to draw conclusions on the formability of polymer sheets through the evaluation of the forming angles and the observation of the failure mechanisms.

Combined contactless conductometric, photometric, and fluorimetric single point detector for capillary separation methods.

Science.gov (United States)

Ryvolová, Markéta; Preisler, Jan; Foret, Frantisek; Hauser, Peter C; Krásenský, Pavel; Paull, Brett; Macka, Mirek

2010-01-01

This work for the first time combines three on-capillary detection methods, namely, capacitively coupled contactless conductometric (C(4)D), photometric (PD), and fluorimetric (FD), in a single (identical) point of detection cell, allowing concurrent measurements at a single point of detection for use in capillary electrophoresis, capillary electrochromatography, and capillary/nanoliquid chromatography. The novel design is based on a standard 6.3 mm i.d. fiber-optic SMA adapter with a drilled opening for the separation capillary to go through, to which two concentrically positioned C(4)D detection electrodes with a detection gap of 7 mm were added on each side acting simultaneously as capillary guides. The optical fibers in the SMA adapter were used for the photometric signal (absorbance), and another optical fiber at a 45 degrees angle to the capillary was applied to collect the emitted light for FD. Light emitting diodes (255 and 470 nm) were used as light sources for the PD and FD detection modes. LOD values were determined under flow-injection conditions to exclude any stacking effects: For the 470 nm LED limits of detection (LODs) for FD and PD were for fluorescein (1 x 10(-8) mol/L) and tartrazine (6 x 10(-6) mol/L), respectively, and the LOD for the C(4)D was for magnesium chloride (5 x 10(-7) mol/L). The advantage of the three different detection signals in a single point is demonstrated in capillary electrophoresis using model mixtures and samples including a mixture of fluorescent and nonfluorescent dyes and common ions, underivatized amino acids, and a fluorescently labeled digest of bovine serum albumin.

High precision wavefront control in point spread function engineering for single emitter localization

NARCIS (Netherlands)

Siemons, M.E.; Thorsen, R.Ø; Smith, C.S.; Stallinga, S.

2018-01-01

Point spread function (PSF) engineering is used in single emitter localization to measure the emitter position in 3D and possibly other parameters such as the emission color or dipole orientation as well. Advanced PSF models such as spline fits to experimental PSFs or the vectorial PSF model can

SCAP-82, Single Scattering, Albedo Scattering, Point-Kernel Analysis in Complex Geometry

International Nuclear Information System (INIS)

Disney, R.K.; Vogtman, S.E.

1987-01-01

1 - Description of problem or function: SCAP solves for radiation transport in complex geometries using the single or albedo scatter point kernel method. The program is designed to calculate the neutron or gamma ray radiation level at detector points located within or outside a complex radiation scatter source geometry or a user specified discrete scattering volume. Geometry is describable by zones bounded by intersecting quadratic surfaces within an arbitrary maximum number of boundary surfaces per zone. Anisotropic point sources are describable as pointwise energy dependent distributions of polar angles on a meridian; isotropic point sources may also be specified. The attenuation function for gamma rays is an exponential function on the primary source leg and the scatter leg with a build- up factor approximation to account for multiple scatter on the scat- ter leg. The neutron attenuation function is an exponential function using neutron removal cross sections on the primary source leg and scatter leg. Line or volumetric sources can be represented as a distribution of isotropic point sources, with un-collided line-of-sight attenuation and buildup calculated between each source point and the detector point. 2 - Method of solution: A point kernel method using an anisotropic or isotropic point source representation is used, line-of-sight material attenuation and inverse square spatial attenuation between the source point and scatter points and the scatter points and detector point is employed. A direct summation of individual point source results is obtained. 3 - Restrictions on the complexity of the problem: - The SCAP program is written in complete flexible dimensioning so that no restrictions are imposed on the number of energy groups or geometric zones. The geometric zone description is restricted to zones defined by boundary surfaces defined by the general quadratic equation or one of its degenerate forms. The only restriction in the program is that the total

Structural peculiarities and point defects of bulk-ZnO single crystals

International Nuclear Information System (INIS)

Kaurova, I.A.; Kuz’micheva, G.M.; Rybakov, V.B.; Cousson, A.; Gayvoronsky, V.Ya.

2014-01-01

Highlights: • ZnO single crystals of different color were grown by the hydrothermal method. • Point defects in ZnO have been firstly investigated by neutron diffraction. • Presence of additional reflections caused by kinetic growth effects was revealed. • The relationship between the color and zinc and oxygen vacancies was found. • Photoinduced variation of transmittance versus the CW laser intensity was analyzed. - Abstract: ZnO single crystals are related to promising direct wide band gap semiconductor materials belonging to the A II B VI type of compounds with wurtzite structure. “Unintentional” n-type conductivity in ZnO may be caused by zinc and oxygen vacancies, and interstitial zinc atoms. To date, the comprehensive structural investigation and analysis of point defects in ZnO is absent in literature. Green, light green and almost colorless ZnO single crystals grown by the hydrothermal method in concentrated alkali solutions 4M(KOH) + 1M(LiOH) + 0.1M(NH 4 OH) on monohedral seeds [0 0 0 1] at crystallization temperatures in the range of 330–350 °C and pressures in the range of 30–50 MPa have been firstly investigated by neutron diffraction. It was revealed the presence of additional reflections (∼12–∼16%) for all the crystals caused by kinetic growth effects that give grounds to assign them to the space group P3 rather than to P6 3 mc. Analysis of the refined compositions together with the color of ZnO crystals does not rule out the relationship between the color and vacancies in the zinc and oxygen positions whose concentration decreases with the discoloration of the samples. The analysis of the photoinduced variation of the total and on-axis transmittance versus the CW laser intensity showed that the colored samples have profound deep defects related to oxygen vacancies

Quantum Point Contact Single-Nucleotide Conductance for DNA and RNA Sequence Identification.

Science.gov (United States)

Afsari, Sepideh; Korshoj, Lee E; Abel, Gary R; Khan, Sajida; Chatterjee, Anushree; Nagpal, Prashant

2017-11-28

Several nanoscale electronic methods have been proposed for high-throughput single-molecule nucleic acid sequence identification. While many studies display a large ensemble of measurements as "electronic fingerprints" with some promise for distinguishing the DNA and RNA nucleobases (adenine, guanine, cytosine, thymine, and uracil), important metrics such as accuracy and confidence of base calling fall well below the current genomic methods. Issues such as unreliable metal-molecule junction formation, variation of nucleotide conformations, insufficient differences between the molecular orbitals responsible for single-nucleotide conduction, and lack of rigorous base calling algorithms lead to overlapping nanoelectronic measurements and poor nucleotide discrimination, especially at low coverage on single molecules. Here, we demonstrate a technique for reproducible conductance measurements on conformation-constrained single nucleotides and an advanced algorithmic approach for distinguishing the nucleobases. Our quantum point contact single-nucleotide conductance sequencing (QPICS) method uses combed and electrostatically bound single DNA and RNA nucleotides on a self-assembled monolayer of cysteamine molecules. We demonstrate that by varying the applied bias and pH conditions, molecular conductance can be switched ON and OFF, leading to reversible nucleotide perturbation for electronic recognition (NPER). We utilize NPER as a method to achieve >99.7% accuracy for DNA and RNA base calling at low molecular coverage (∼12×) using unbiased single measurements on DNA/RNA nucleotides, which represents a significant advance compared to existing sequencing methods. These results demonstrate the potential for utilizing simple surface modifications and existing biochemical moieties in individual nucleobases for a reliable, direct, single-molecule, nanoelectronic DNA and RNA nucleotide identification method for sequencing.

Electroacupuncture at Guanyuan (CV 4), Zusanli (ST 36) and Baihui (DU 20) regulate the aging-related changes in gene expression profile of the hippocampus in sub-acutely aging rats.

Science.gov (United States)

Liu, Jianmin; Liu, Jing; Wang, Guang'an; Liu, Guangya; Zhou, Huanjiao; Fan, Yun; Liang, Fengxia; Wang, Hua

2018-01-01

To investigate the molecular mechanisms of sub-acutely aging and demonstrate the effect of electroacupuncture (EA) at the Guanyuan (CV 4), Zusanli (ST 36) and Baihui (DU 20) acupoint on the sub-acutely aging brain, cDNA microarrays and bioinformatics analyses were carried out. Thirty Sprague-Dawley (SD) male rats were selected and randomly divided into three groups: the control group (C), the sub-acutely aging model group (M) and the electroacupuncture group (M+EA). Sub-acutely aging model rats were obtained by D-galactose s.c. injection continuously for 40 days. Total RNA was extracted from the hippocampus area of brains in three groups for cDNA microarrays. The data of different groups were compared and analyzed by differential expression analysis, Gene ontology (GO) term enrichment, Kyoto Encyclopedia of Genes Genomes (KEGG) pathway enrichment and quantitative real-time PCR. According to the results, 4052 DE genes were identified in our study. Among them, there were 3079 differentially expressed (DE) genes between group M and group C, and these genes are associated with the aging of rats. Moreover, 983 genes were expressed differently in group M+EA compared with group M, revealing that points stimuli could regulate gene expression in brain with aging. Gene ontology (GO) term enrichment and KEGG enrichment were performed to further classify the differential expression genes. Important GO terms and KEGG pathways connected with sub-acutely aging EA effects were identified. At last, 3 significant differentially expressed genes were selected for real-time quantitative PCR to clarify the cDNA microarray results. In conclusion, the cDNA microarray data first compared and analyzed the differences of gene expression profile in the hippocampus of rats in different groups, which contribute to our knowledge on the molecular mechanisms of EA towards sub-acutely aging.

UABUC - Single energy point model burnup computer code for water reactors

International Nuclear Information System (INIS)

El-Meshad, Y.; Morsy, S.; El-Osery, I.A.

1981-01-01

UABUC is a single energy point reactor burnup computer program in FORTRAN language. The program calculates the change in the isotopic composition of the uranium fuel as a function of irradiation time with all its associated quantities such as the average point flux, the conversion ratio, macroscopic fuel cross sections, and the point reactivity profile. A step-wise time analytical solution was developed for the nonlinear first order burnup differential equations. The ''Westcott'' convention of the effective cross sections was used except for plutonium-240 and uranium-238. For plutonium-240, an effective microscopic cross section was derived from the direct physical arguments taking into account the selfshielding effect of plutonium-240 as well as the 1 ev. resonance absorption. For uranium-238, an effective cross section, reflecting the effect of fast fission and resonance absorption was used. The fission products were treated in the three groups with 50, 300, and 800 barns. The yields in the groups were treated as functions of the type of fissionable nuclides, the effective neutron temperature, and the epithermal index. Xenon-135 and Samarium-149 were treated separately as functions of irradiation time. (author)

Single-point reactive power control method on voltage rise mitigation in residential networks with high PV penetration

DEFF Research Database (Denmark)

Hasheminamin, Maryam; Agelidis, Vassilios; Ahmadi, Abdollah

2018-01-01

Voltage rise (VR) due to reverse power flow is an important obstacle for high integration of Photovoltaic (PV) into residential networks. This paper introduces and elaborates a novel methodology of an index-based single-point-reactive power-control (SPRPC) methodology to mitigate voltage rise by ...... system with high r/x ratio. Efficacy, effectiveness and cost study of SPRPC is compared to droop control to evaluate its advantages.......Voltage rise (VR) due to reverse power flow is an important obstacle for high integration of Photovoltaic (PV) into residential networks. This paper introduces and elaborates a novel methodology of an index-based single-point-reactive power-control (SPRPC) methodology to mitigate voltage rise...... by absorbing adequate reactive power from one selected point. The proposed index utilizes short circuit analysis to select the best point to apply this Volt/Var control method. SPRPC is supported technically and financially by distribution network operator that makes it cost effective, simple and efficient...

Electrically continuous graphene from single crystal copper verified by terahertz conductance spectroscopy and micro four-point probe

DEFF Research Database (Denmark)

Buron, Jonas Christian Due; Pizzocchero, Filippo; Jessen, Bjarke Sørensen

2014-01-01

noninvasive conductance characterization methods: ultrabroadband terahertz time-domain spectroscopy and micro four-point probe, which probe the electrical properties of the graphene film on different length scales, 100 nm and 10 μm, respectively. Ultrabroadband terahertz time-domain spectroscopy allows......- and microscale electrical continuity of single layer graphene grown on centimeter-sized single crystal copper with that of previously studied graphene films, grown on commercially available copper foil, after transfer to SiO2 surfaces. The electrical continuity of the graphene films is analyzed using two....... Micro four-point probe resistance values measured on graphene grown on single crystalline copper in two different voltage-current configurations show close agreement with the expected distributions for a continuous 2D conductor, in contrast with previous observations on graphene grown on commercial...

Expanding the Operational Limits of the Single-Point Impedance Diagnostic for Internal Temperature Monitoring of Lithium-ion Batteries

International Nuclear Information System (INIS)

Spinner, Neil S.; Love, Corey T.; Rose-Pehrsson, Susan L.; Tuttle, Steven G.

2015-01-01

Highlights: • Single-point impedance diagnostic technique demonstrated for lithium-ion batteries • Correlation between imaginary impedance and internal temperature determined • Instantaneous monitoring of commercial lithium-ion battery internal temperature • Expanded temperature range from −10°C up to 95°C • Non-invasive method useful for practical temperature monitoring of commercial cells - Abstract: Instantaneous internal temperature monitoring of a commercial 18650 LiCoO 2 lithium-ion battery was performed using a single-point EIS measurement. A correlation between the imaginary impedance, –Z imag , and internal temperature at 300 Hz was developed that was independent of the battery’s state of charge. An Arrhenius-type dependence was applied, and the activation energy for SEI ionic conductivity was found to be 0.13 eV. Two separate temperature-time experiments were conducted with different sequences of temperature, and single-point impedance tests at 300 Hz were performed to validate the correlation. Limitations were observed with the upper temperature range (68°C < T < 95°C), and consequently a secondary, empirical fit was applied for this upper range to improve accuracy. Average differences between actual and fit temperatures decreased around 3-7°C for the upper range with the secondary correlation. The impedance response at this frequency corresponded to the anode/SEI layer, and the SEI is reported to be thermally stable up to around 100°C, at which point decomposition may occur leading to battery deactivation and/or total failure. It is therefore of great importance to be able to track internal battery temperatures up to this critical point of 100°C, and this work demonstrates an expansion of the single-point EIS diagnostic to these elevated temperatures

Alternative methods for CYP2D6 phenotyping: comparison of dextromethorphan metabolic ratios from AUC, single point plasma, and urine.

Science.gov (United States)

Chen, Rui; Wang, Haotian; Shi, Jun; Hu, Pei

2016-05-01

CYP2D6 is a high polymorphic enzyme. Determining its phenotype before CYP2D6 substrate treatment can avoid dose-dependent adverse events or therapeutic failures. Alternative phenotyping methods of CYP2D6 were compared to aluate the appropriate and precise time points for phenotyping after single-dose and ultiple-dose of 30-mg controlled-release (CR) dextromethorphan (DM) and to explore the antimodes for potential sampling methods. This was an open-label, single and multiple-dose study. 21 subjects were assigned to receive a single dose of CR DM 30 mg orally, followed by a 3-day washout period prior to oral administration of CR DM 30 mg every 12 hours for 6 days. Metabolic ratios (MRs) from AUC∞ after single dosing and from AUC0-12h at steady state were taken as the gold standard. The correlations of metabolic ratios of DM to dextrorphan (MRDM/DX) values based on different phenotyping methods were assessed. Linear regression formulas were derived to calculate the antimodes for potential sample methods. In the single-dose part of the study statistically significant correlations were found between MRDM/DX from AUC∞ and from serial plasma points from 1 to 30 hours or from urine (all p-values < 0.001). In the multiple-dose part, statistically significant correlations were found between MRDM/DX from AUC0-12h on day 6 and MRDM/DX from serial plasma points from 0 to 36 hours after the last dosing (all p-values < 0.001). Based on reported urinary antimode and linear regression analysis, the antimodes of AUC and plasma points were derived to profile the trend of antimodes as the drug concentrations changed. MRDM/DX from plasma points had good correlations with MRDM/DX from AUC. Plasma points from 1 to 30 hours after single dose of 30-mg CR DM and any plasma point at steady state after multiple doses of CR DM could potentially be used for phenotyping of CYP2D6.

Dynamics of single photon transport in a one-dimensional waveguide two-point coupled with a Jaynes-Cummings system

KAUST Repository

Wang, Yuwen

2016-09-22

We study the dynamics of an ultrafast single photon pulse in a one-dimensional waveguide two-point coupled with a Jaynes-Cummings system. We find that for any single photon input the transmissivity depends periodically on the separation between the two coupling points. For a pulse containing many plane wave components it is almost impossible to suppress transmission, especially when the width of the pulse is less than 20 times the period. In contrast to plane wave input, the waveform of the pulse can be modified by controlling the coupling between the waveguide and Jaynes-Cummings system. Tailoring of the waveform is important for single photon manipulation in quantum informatics. © The Author(s) 2016.

Relationship Between and Laser Acupuncture Analgesia and the Function of Mast Cells in Adjuvant Arthritis Rats Treated by Acupuncture%Relationship Between and Laser Acupuncture Analgesia and the Function of Mast Cells in Adjuvant Arthritis Rats

Institute of Scientific and Technical Information of China (English)

程珂; 丁光宏; 沈雪勇; 吴凡

2009-01-01

Objective:To observe the analgesia effect and of low-level combined- and single-laser irradiation on Zusanli (ST 36) in rats and the relationship between mast cell degranulation and laser acupuncture analgesia.Methods: A total of 66 Sprague Dawley (SD) rats were randomly assigned into normal control,model control,sham irradiation,10.6 μm laser (220 mW,40 Hz) 650nm laser(36mW,continuous),combined laser (10.6 μm+ 650 nm) groups.Arthritis mode 1 was established by injection of Complete Freund's Adjuvant (0.05 mL) into the left ankle joint.The paw withdrawal latency (PWL) was detected with a radiant heat algesimeter.Zusanli (ST 36) was irradiated with sham,single or combined laser for 30 min.After sacrifice under anesthesia (1% embutal),tissues of Zusanli (ST 36) area were sampled,sliced (5 μm) and stained with Toluidine Blue for skin for observing the mast cell degranulation.Results:Compared with model control and sham group,the pain threshold increased significantly in 650nm and combined laser groups (P＜0.01),while remained no significant difference in 10.6 μm group.Compared with model and sham group,the degranulation ratios of mast cells in 650nm and combined laser group were significantly higher (P＜0.001),while remained no significant difference in 10.6 μm group.The linear correlation coefficient between degranulation ratios of mast cells and PWL after laser acupuncture is 0.737 (P＜0.001).Conclusion:Both 650 nm and combined laser stimulation of Zusanli (ST 36) can effectively raise pain threshold,and enhance degranulation ratio of mast cells at the stimulated acupoint.The result also suggested a linear correlation between degranulation ratio of mast cell and analgesia effect.

An elevated neutrophil-lymphocyte ratio is associated with adverse outcomes following single time-point paracetamol (acetaminophen) overdose: a time-course analysis.

Science.gov (United States)

Craig, Darren G; Kitto, Laura; Zafar, Sara; Reid, Thomas W D J; Martin, Kirsty G; Davidson, Janice S; Hayes, Peter C; Simpson, Kenneth J

2014-09-01

The innate immune system is profoundly dysregulated in paracetamol (acetaminophen)-induced liver injury. The neutrophil-lymphocyte ratio (NLR) is a simple bedside index with prognostic value in a number of inflammatory conditions. To evaluate the prognostic accuracy of the NLR in patients with significant liver injury following single time-point and staggered paracetamol overdoses. Time-course analysis of 100 single time-point and 50 staggered paracetamol overdoses admitted to a tertiary liver centre. Timed laboratory samples were correlated with time elapsed after overdose or admission, respectively, and the NLR was calculated. A total of 49/100 single time-point patients developed hepatic encephalopathy (HE). Median NLRs were higher at both 72 (P=0.0047) and 96 h after overdose (P=0.0041) in single time-point patients who died or were transplanted. Maximum NLR values by 96 h were associated with increasing HE grade (P=0.0005). An NLR of more than 16.7 during the first 96 h following overdose was independently associated with the development of HE [odds ratio 5.65 (95% confidence interval 1.67-19.13), P=0.005]. Maximum NLR values by 96 h were strongly associated with the requirement for intracranial pressure monitoring (Pparacetamol overdoses. Future studies should assess the value of incorporating the NLR into existing prognostic and triage indices of single time-point paracetamol overdose.

[Study on effects of low frequency pulse plus auricular point magnetic therapy on electrogastrogram and clinical therapeutic effect in the patient of functional dyspepsia].

Science.gov (United States)

Wang, Yan-Gang; Yao, Shu-Kun

2007-04-01

To compare therapeutic effects of low frequency pulse plus auricular point magnetic therapy and prepulsid on functional dyspepsia (FD). Fifty cases of FD were randomly divided into a treatment group and a control group. The treatment group were treated with low frequency pulse stimulation on Zhongwan (CV 12), Weishu (BL 21), Neiguan (PC 6), Zusanli (ST 36), with Fenglong (ST 40) and Sanyinjiao (SP 6) selected according to syndrome differentiation, once a day, 30 min each session. The control group were treated with oral administration of prepulsid. Five days constituted one course. The scores of symptoms and parameters of electrogastrogram (EGG) before and after treatment and the therapeutic effect were investigated. After treatment, the symptom scores significantly decreased (P magnetic therapy can significantly improve the clinical symptoms and gastric activities in the patient of FD, with a better therapeutic effect than prepulsid.

Single stage buck-boost DC-AC neutral point clamped inverter

DEFF Research Database (Denmark)

Mo, Wei; Loh, Poh Chiang; Andrew, A.

2012-01-01

This paper proposes a new single stage buck-boost DC-AC neutral point clamped inverter topology which integrates the cascaded configurations of recently introduced inductor-capacitor-capacitor-transformer impedance source network (by Adamowicz) and classic NPC configuration. As a consequence......, it has enhanced buck-boost functionality and low output voltage distortions compared to the traditional Z-source inverter; it has continuous input current which reduces the source stress and inverter noise; it also contains two built-in capacitors which can block the DC current in the transformer...... windings thus preventing the core from saturation; lowers the voltage stresses and power losses of inverter switches and reduces the sizes of filtering devices and as well as obtains better output performance compared to the original two-level Z-source inverters. A phase disposition pulse width modulation...

Dissection of Biological Property of Chinese Acupuncture Point Zusanli Based on Long-Term Treatment via Modulating Multiple Metabolic Pathways

Directory of Open Access Journals (Sweden)

Guangli Yan

2013-01-01

Full Text Available Acupuncture has a history of over 3000 years and is a traditional Chinese medical therapy that uses hair-thin metal needles to puncture the skin at specific points on the body to promote wellbeing, while its molecular mechanism and ideal biological pathways are still not clear. High-throughput metabolomics is the global assessment of endogenous metabolites within a biologic system and can potentially provide a more accurate snap shot of the actual physiological state. We hypothesize that acupuncture-treated human would produce unique characterization of metabolic phenotypes. In this study, UPLC/ESI-HDMS coupled with pattern recognition methods and system analysis were carried out to investigate the mechanism and metabolite biomarkers for acupuncture treatment at “Zusanli” acupoint (ST-36 as a case study. The top 5 canonical pathways including alpha-linolenic acid metabolism, d-glutamine and d-glutamate metabolism, citrate cycle, alanine, aspartate, and glutamate metabolism, and vitamin B6 metabolism pathways were acutely perturbed, and 53 differential metabolites were identified by chemical profiling and may be useful to clarify the physiological basis and mechanism of ST-36. More importantly, network construction has led to the integration of metabolites associated with the multiple perturbation pathways. Urine metabolic profiling might be a promising method to investigate the molecular mechanism of acupuncture.

Comparison of Single and Multi-Scale Method for Leaf and Wood Points Classification from Terrestrial Laser Scanning Data

Science.gov (United States)

Wei, Hongqiang; Zhou, Guiyun; Zhou, Junjie

2018-04-01

The classification of leaf and wood points is an essential preprocessing step for extracting inventory measurements and canopy characterization of trees from the terrestrial laser scanning (TLS) data. The geometry-based approach is one of the widely used classification method. In the geometry-based method, it is common practice to extract salient features at one single scale before the features are used for classification. It remains unclear how different scale(s) used affect the classification accuracy and efficiency. To assess the scale effect on the classification accuracy and efficiency, we extracted the single-scale and multi-scale salient features from the point clouds of two oak trees of different sizes and conducted the classification on leaf and wood. Our experimental results show that the balanced accuracy of the multi-scale method is higher than the average balanced accuracy of the single-scale method by about 10 % for both trees. The average speed-up ratio of single scale classifiers over multi-scale classifier for each tree is higher than 30.

Visualized study on specific points on demand curves and flow patterns in a single-side heated narrow rectangular channel

International Nuclear Information System (INIS)

Wang Junfeng; Huang Yanping; Wang Yanlin

2011-01-01

Highlights: → Specific points on the demand curve and flow patterns are visually studied. → Bubbly, churn, and annular flows were observed. → Onset of flow instability and bubbly-churn transition occurs at the same time. → The evolution of specific points and flow pattern transitions were examined. - Abstract: A simultaneous visualization and measurement study on some specific points on demand curves, such as onset of nucleate boiling (ONB), onset of significant void (OSV), onset of flow instability (OFI), and two-phase flow patterns in a single-side heated narrow rectangular channel, having a width of 40 mm and a gap of 3 mm, was carried out. New experimental approaches were adopted to identify OSV and OFI in a narrow rectangular channel. Under experimental conditions, the ONB could be predicted well by the Sato and Matsumura model. The OSV model of Bowring can reasonably predict the OSV if the single-side heated condition is considered. The OFI was close to the saturated boiling point and could be described accurately by Kennedy's correlation. The two-phase flow patterns observed in this experiment could be classified into bubbly, churn, and annular flow. Slug flow was never observed. The OFI always occurred when the bubbles at the channel exit began to coalesce, which corresponded to the beginning of the bubbly-churn transition in flow patterns. Finally, the evolution of specific points and flow pattern transitions were examined in a single-side heated narrow rectangular channel.

Point defects and electric compensation in gallium arsenide single crystals; Punktdefekte und elektrische Kompensation in Galliumarsenid-Einkristallen

Energy Technology Data Exchange (ETDEWEB)

Kretzer, Ulrich

2007-12-10

In the present thesis the point-defect budget of gallium arsenide single crystals with different dopings is studied. It is shown, in which way the concentration of the single point defects depende on the concentration of the dopants, the stoichiometry deviation, and the position of the Fermi level. For this serve the results of the measurement-technical characterization of a large number of samples, in the fabrication of which these parameters were directedly varied. The main topic of this thesis lies in the development of models, which allow a quantitative description of the experimentally studied electrical and optical properties of gallium arsenide single crystals starting from the point-defect concentrations. Because from point defects charge carriers can be set free, their concentration determines essentially the charge-carrier concentration in the bands. In the ionized state point defects act as scattering centers for free charge carriers and influence by this the drift mobility of the charge carriers. A thermodynamic modeling of the point-defect formation yields statements on the equilibrium concentrations of the point defects in dependence on dopant concentration and stoichiometry deviation. It is show that the electrical properties of the crystals observed at room temperature result from the kinetic suppression of processes, via which the adjustment of a thermodynamic equilibrium between the point defects is mediated. [German] In der vorliegenden Arbeit wird der Punktdefekthaushalt von Galliumarsenid-Einkristallen mit unterschiedlichen Dotierungen untersucht. Es wird gezeigt, in welcher Weise die Konzentration der einzelnen Punktdefekte von der Konzentration der Dotierstoffe, der Stoechiometrieabweichung und der Lage des Ferminiveaus abhaengen. Dazu dienen die Ergebnisse der messtechnischen Charakterisierung einer grossen Anzahl von Proben, bei deren Herstellung diese Parameter gezielt variiert wurden. Der Schwerpunkt der Arbeit liegt in der Entwicklung

Point of zero potential of single-crystal electrode/inert electrolyte interface.

Science.gov (United States)

Zarzycki, Piotr; Preočanin, Tajana

2012-03-15

Most of the environmentally important processes occur at the specific hydrated mineral faces. Their rates and mechanisms are in part controlled by the interfacial electrostatics, which can be quantitatively described by the point of zero potential (PZP). Unfortunately, the PZP value of specific crystal face is very difficult to be experimentally determined. Here we show that PZP can be extracted from a single-crystal electrode potentiometric titration, assuming the stable electrochemical cell resistivity and lack of specific electrolyte ions sorption. Our method is based on determining a common intersection point of the electrochemical cell electromotive force at various ionic strengths, and it is illustrated for a few selected surfaces of rutile, hematite, silver chloride, and bromide monocrystals. In the case of metal oxides, we have observed the higher PZP values than those theoretically predicted using the MultiSite Complexation Model (MUSIC), that is, 8.4 for (001) hematite (MUSIC-predicted ~6), 8.7 for (110) rutile (MUSIC-predicted ~6), and about 7 for (001) rutile (MUSIC-predicted 6.6). In the case of silver halides, the order of estimated PZP values (6.4 for AgClsoils and groundwaters. Copyright © 2012 Elsevier Inc. All rights reserved.

Service Matters: Single Service Point as a Collaborative and Professional Learning Initiative for Service Excellence

Science.gov (United States)

Chauvet, Marianne; Bourbous, Vicki; Liston, Frances

2016-01-01

Changes and innovations in higher education learning and teaching acted as a catalyst for rethinking the way in which service was delivered to library clients at Australian Catholic University. The Single Service Point was piloted at one campus library in 2014 to develop a best practice approach to service delivery. The merging of cultures within…

Exposure buildup factors for a cobalt-60 point isotropic source for single and two layer slabs

International Nuclear Information System (INIS)

Chakarova, R.

1992-01-01

Exposure buildup factors for point isotropic cobalt-60 sources are calculated by the Monte Carlo method with statistical errors ranging from 1.5 to 7% for 1-5 mean free paths (mfp) thick water and iron single slabs and for 1 and 2 mfp iron layers followed by water layers 1-5 mfp thick. The computations take into account Compton scattering. The Monte Carlo data for single slab geometries are approximated by Geometric Progression formula. Kalos's formula using the calculated single slab buildup factors may be applied to reproduce the data for two-layered slabs. The presented results and discussion may help when choosing the manner in which the radiation field gamma irradiation units will be described. (author)

High performance control strategy for single-phase three-level neutral-point-clamped traction four-quadrant converters

DEFF Research Database (Denmark)

Kejian, Song; Konstantinou, Georgios; Jing, Li

2017-01-01

Operational data from Chinese railways indicate a number of challenges for traction four-quadrant converter (4QC) control including low-order voltage and current harmonics and reference tracking. A control strategy for a single-phase three-level neutral-point-clamped 4QC employed in the electric...

Modelling of thermal field and point defect dynamics during silicon single crystal growth using CZ technique

Science.gov (United States)

Sabanskis, A.; Virbulis, J.

2018-05-01

Mathematical modelling is employed to numerically analyse the dynamics of the Czochralski (CZ) silicon single crystal growth. The model is axisymmetric, its thermal part describes heat transfer by conduction and thermal radiation, and allows to predict the time-dependent shape of the crystal-melt interface. Besides the thermal field, the point defect dynamics is modelled using the finite element method. The considered process consists of cone growth and cylindrical phases, including a short period of a reduced crystal pull rate, and a power jump to avoid large diameter changes. The influence of the thermal stresses on the point defects is also investigated.

Hysteresis compensation for piezoelectric actuators in single-point diamond turning

Science.gov (United States)

Wang, Haifeng; Hu, Dejin; Wan, Daping; Liu, Hongbin

2006-02-01

In recent years, interests have been growing for fast tool servo (FTS) systems to increase the capability of existing single-point diamond turning machines. Although piezoelectric actuator is the most universal base of FTS system due to its high stiffness, accuracy and bandwidth, nonlinearity in piezoceramics limits both the static and dynamic performance of piezoelectric-actuated control systems evidently. To compensate the nonlinear hysteresis behavior of piezoelectric actuators, a hybrid model coupled with Preisach model and feedforward neural network (FNN) has been described. Since the training of FNN does not require a special calibration sequence, it is possible for on-line identification and real-time implementation with general operating data of a specific piezoelectric actuator. To describe the rate dependent behavior of piezoelectric actuators, a hybrid dynamic model was developed to predict the response of piezoelectric actuators in a wider range of input frequency. Experimental results show that a maximal error of less than 3% was accomplished by this dynamic model.

A single FPGA-based portable ultrasound imaging system for point-of-care applications.

Science.gov (United States)

Kim, Gi-Duck; Yoon, Changhan; Kye, Sang-Bum; Lee, Youngbae; Kang, Jeeun; Yoo, Yangmo; Song, Tai-kyong

2012-07-01

We present a cost-effective portable ultrasound system based on a single field-programmable gate array (FPGA) for point-of-care applications. In the portable ultrasound system developed, all the ultrasound signal and image processing modules, including an effective 32-channel receive beamformer with pseudo-dynamic focusing, are embedded in an FPGA chip. For overall system control, a mobile processor running Linux at 667 MHz is used. The scan-converted ultrasound image data from the FPGA are directly transferred to the system controller via external direct memory access without a video processing unit. The potable ultrasound system developed can provide real-time B-mode imaging with a maximum frame rate of 30, and it has a battery life of approximately 1.5 h. These results indicate that the single FPGA-based portable ultrasound system developed is able to meet the processing requirements in medical ultrasound imaging while providing improved flexibility for adapting to emerging POC applications.

Highly macroscopically degenerated single-point ground states as source of specific heat capacity anomalies in magnetic frustrated systems

Science.gov (United States)

Jurčišinová, E.; Jurčišin, M.

2018-04-01

Anomalies of the specific heat capacity are investigated in the framework of the exactly solvable antiferromagnetic spin- 1 / 2 Ising model in the external magnetic field on the geometrically frustrated tetrahedron recursive lattice. It is shown that the Schottky-type anomaly in the behavior of the specific heat capacity is related to the existence of unique highly macroscopically degenerated single-point ground states which are formed on the borders between neighboring plateau-like ground states. It is also shown that the very existence of these single-point ground states with large residual entropies predicts the appearance of another anomaly in the behavior of the specific heat capacity for low temperatures, namely, the field-induced double-peak structure, which exists, and should be observed experimentally, along with the Schottky-type anomaly in various frustrated magnetic system.

Detection of Single Tree Stems in Forested Areas from High Density ALS Point Clouds Using 3d Shape Descriptors

Science.gov (United States)

Amiri, N.; Polewski, P.; Yao, W.; Krzystek, P.; Skidmore, A. K.

2017-09-01

Airborne Laser Scanning (ALS) is a widespread method for forest mapping and management purposes. While common ALS techniques provide valuable information about the forest canopy and intermediate layers, the point density near the ground may be poor due to dense overstory conditions. The current study highlights a new method for detecting stems of single trees in 3D point clouds obtained from high density ALS with a density of 300 points/m2. Compared to standard ALS data, due to lower flight height (150-200 m) this elevated point density leads to more laser reflections from tree stems. In this work, we propose a three-tiered method which works on the point, segment and object levels. First, for each point we calculate the likelihood that it belongs to a tree stem, derived from the radiometric and geometric features of its neighboring points. In the next step, we construct short stem segments based on high-probability stem points, and classify the segments by considering the distribution of points around them as well as their spatial orientation, which encodes the prior knowledge that trees are mainly vertically aligned due to gravity. Finally, we apply hierarchical clustering on the positively classified segments to obtain point sets corresponding to single stems, and perform ℓ1-based orthogonal distance regression to robustly fit lines through each stem point set. The ℓ1-based method is less sensitive to outliers compared to the least square approaches. From the fitted lines, the planimetric tree positions can then be derived. Experiments were performed on two plots from the Hochficht forest in Oberösterreich region located in Austria.We marked a total of 196 reference stems in the point clouds of both plots by visual interpretation. The evaluation of the automatically detected stems showed a classification precision of 0.86 and 0.85, respectively for Plot 1 and 2, with recall values of 0.7 and 0.67.

Quantifying the Impact of Single Bit Flips on Floating Point Arithmetic

Energy Technology Data Exchange (ETDEWEB)

Elliott, James J [ORNL; Mueller, Frank [North Carolina State University; Stoyanov, Miroslav K [ORNL; Webster, Clayton G [ORNL

2013-08-01

In high-end computing, the collective surface area, smaller fabrication sizes, and increasing density of components have led to an increase in the number of observed bit flips. If mechanisms are not in place to detect them, such flips produce silent errors, i.e. the code returns a result that deviates from the desired solution by more than the allowed tolerance and the discrepancy cannot be distinguished from the standard numerical error associated with the algorithm. These phenomena are believed to occur more frequently in DRAM, but logic gates, arithmetic units, and other circuits are also susceptible to bit flips. Previous work has focused on algorithmic techniques for detecting and correcting bit flips in specific data structures, however, they suffer from lack of generality and often times cannot be implemented in heterogeneous computing environment. Our work takes a novel approach to this problem. We focus on quantifying the impact of a single bit flip on specific floating-point operations. We analyze the error induced by flipping specific bits in the most widely used IEEE floating-point representation in an architecture-agnostic manner, i.e., without requiring proprietary information such as bit flip rates and the vendor-specific circuit designs. We initially study dot products of vectors and demonstrate that not all bit flips create a large error and, more importantly, expected value of the relative magnitude of the error is very sensitive on the bit pattern of the binary representation of the exponent, which strongly depends on scaling. Our results are derived analytically and then verified experimentally with Monte Carlo sampling of random vectors. Furthermore, we consider the natural resilience properties of solvers based on the fixed point iteration and we demonstrate how the resilience of the Jacobi method for linear equations can be significantly improved by rescaling the associated matrix.

Single-Carrier Modulation for Neutral-Point-Clamped Inverters in Three-Phase Transformerless Photovoltaic Systems

DEFF Research Database (Denmark)

Guo, Xiaoqiang; Cavalcanti, Marcelo C.; Farias, Alexandre M.

2013-01-01

Modulation strategy is one of the most important issues for three-level neutral-point-clamped inverters in three-phase transformerless photovoltaic systems. A challenge for modulation is how to keep the common-mode voltages constant to reduce the leakage currents. A single-carrier modulation...... strategy is proposed. It has a very simple structure, and the common-mode voltages can be kept constant with no need of complex space-vector modulation or multicarrier pulsewidth modulation. Experimental results verify the theoretical analysis and the effectiveness of the presented method....

Lithium-Ion Cell Fault Detection by Single-Point Impedance Diagnostic and Degradation Mechanism Validation for Series-Wired Batteries Cycled at 0 °C

Directory of Open Access Journals (Sweden)

Corey T. Love

2018-04-01

Full Text Available The utility of a single-point impedance-based technique to monitor the state-of-health of a pack of four 18650 lithium-ion cells wired in series (4S was demonstrated in a previous publication. This work broadens the applicability of the single-point monitoring technique to identify temperature induced faults within 4S packs at 0 °C by two distinct discharge cut-off thresholds: individual cell cut-off and pack voltage cut-off. The results show how the single-point technique applied to a 4S pack can identify cell faults induced by low temperature degradation when plotted on a unique state-of-health map. Cell degradation is validated through an extensive incremental capacity technique to quantify capacity loss due to low temperature cycling and investigate the underpinnings of cell failure.

Tilted Light Sheet Microscopy with 3D Point Spread Functions for Single-Molecule Super-Resolution Imaging in Mammalian Cells.

Science.gov (United States)

Gustavsson, Anna-Karin; Petrov, Petar N; Lee, Maurice Y; Shechtman, Yoav; Moerner, W E

2018-02-01

To obtain a complete picture of subcellular nanostructures, cells must be imaged with high resolution in all three dimensions (3D). Here, we present tilted light sheet microscopy with 3D point spread functions (TILT3D), an imaging platform that combines a novel, tilted light sheet illumination strategy with engineered long axial range point spread functions (PSFs) for low-background, 3D super localization of single molecules as well as 3D super-resolution imaging in thick cells. TILT3D is built upon a standard inverted microscope and has minimal custom parts. The axial positions of the single molecules are encoded in the shape of the PSF rather than in the position or thickness of the light sheet, and the light sheet can therefore be formed using simple optics. The result is flexible and user-friendly 3D super-resolution imaging with tens of nm localization precision throughout thick mammalian cells. We validated TILT3D for 3D super-resolution imaging in mammalian cells by imaging mitochondria and the full nuclear lamina using the double-helix PSF for single-molecule detection and the recently developed Tetrapod PSF for fiducial bead tracking and live axial drift correction. We envision TILT3D to become an important tool not only for 3D super-resolution imaging, but also for live whole-cell single-particle and single-molecule tracking.

Tilted light sheet microscopy with 3D point spread functions for single-molecule super-resolution imaging in mammalian cells

Science.gov (United States)

Gustavsson, Anna-Karin; Petrov, Petar N.; Lee, Maurice Y.; Shechtman, Yoav; Moerner, W. E.

2018-02-01

To obtain a complete picture of subcellular nanostructures, cells must be imaged with high resolution in all three dimensions (3D). Here, we present tilted light sheet microscopy with 3D point spread functions (TILT3D), an imaging platform that combines a novel, tilted light sheet illumination strategy with engineered long axial range point spread functions (PSFs) for low-background, 3D super localization of single molecules as well as 3D super-resolution imaging in thick cells. TILT3D is built upon a standard inverted microscope and has minimal custom parts. The axial positions of the single molecules are encoded in the shape of the PSF rather than in the position or thickness of the light sheet, and the light sheet can therefore be formed using simple optics. The result is flexible and user-friendly 3D super-resolution imaging with tens of nm localization precision throughout thick mammalian cells. We validated TILT3D for 3D superresolution imaging in mammalian cells by imaging mitochondria and the full nuclear lamina using the double-helix PSF for single-molecule detection and the recently developed Tetrapod PSF for fiducial bead tracking and live axial drift correction. We envision TILT3D to become an important tool not only for 3D super-resolution imaging, but also for live whole-cell single-particle and single-molecule tracking.

A Kind of Single-frequency Precise Point Positioning Algorithm Based on the Raw Observations

Directory of Open Access Journals (Sweden)

WANG Li

2015-01-01

Full Text Available A kind of single-frequency precise point positioning (PPP algorithm based on the raw observations is presented in this paper. By this algorithm, the ionospheric delays were corrected efficiently by means of adding the ionospheric delay prior information and the virtual observation equations with the spatial and temporal constraints, and they were estimated as the unknown parameters simultaneously with other positioning parameters. Then, a dataset of 178 International GNSS Service (IGS stations at day 72 in 2012 was used to evaluate the convergence speed, the positioning accuracy and the accuracy of the retrieved ionospheric VTEC. The series of results have shown that the convergence speed and stability of the new algorithm are much better than the traditional PPP algorithm, and the positioning accuracy of about 2-3 cm and 2-3 dm can be achieved respectively for static and kinematic positioning with the single-frequency observations' daily solution. The average bias of ionospheric total electron content retrieved by the single-frequency PPP and dual-frequency PPP is less than 5 TECU. So the ionospheric total electron content can be used as a kind of auxiliary products in GPS positioning.

Point contact to single-crystalline diamond

Czech Academy of Sciences Publication Activity Database

Mareš, Jiří J.; Hubík, Pavel; Uxa, Štěpán; Krištofik, Jozef; Kozak, Halyna

2012-01-01

Roč. 27, č. 6 (2012), 1-4 ISSN 0268-1242 R&D Projects: GA ČR GAP204/10/0212 Institutional research plan: CEZ:AV0Z10100521 Keywords : point-contact * diamond * space-charge–limited transport Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.921, year: 2012

Analysis of payload bay magnetic fields due to dc power multipoint and single point ground configurations

Science.gov (United States)

Lawton, R. M.

1976-01-01

An analysis of magnetic fields in the Orbiter Payload Bay resulting from the present grounding configuration (structure return) was presented and the amount of improvement that would result from installing wire returns for the three dc power buses was determined. Ac and dc magnetic fields at five points in a cross-section of the bay are calculated for both grounding configurations. Y and Z components of the field at each point are derived in terms of a constant coefficient and the current amplitude of each bus. The dc loads assumed are 100 Amperes for each bus. The ac noise current used is a spectrum 6 db higher than the Orbiter equipment limit for narrowband conducted emissions. It was concluded that installing return wiring to provide a single point ground for the dc Buses in the Payload Bay would reduce the ac and dc magnetic field intensity by approximately 30 db.

A Single Phase Doubly Grounded Semi-Z-Source Inverter for Photovoltaic (PV Systems with Maximum Power Point Tracking (MPPT

Directory of Open Access Journals (Sweden)

Tofael Ahmed

2014-06-01

Full Text Available In this paper, a single phase doubly grounded semi-Z-source inverter with maximum power point tracking (MPPT is proposed for photovoltaic (PV systems. This proposed system utilizes a single-ended primary inductor (SEPIC converter as DC-DC converter to implement the MPPT algorithm for tracking the maximum power from a PV array and a single phase semi-Z-source inverter for integrating the PV with AC power utilities. The MPPT controller utilizes a fast-converging algorithm to track the maximum power point (MPP and the semi-Z-source inverter utilizes a nonlinear SPWM to produce sinusoidal voltage at the output. The proposed system is able to track the MPP of PV arrays and produce an AC voltage at its output by utilizing only three switches. Experimental results show that the fast-converging MPPT algorithm has fast tracking response with appreciable MPP efficiency. In addition, the inverter shows the minimization of common mode leakage current with its ground sharing feature and reduction of the THD as well as DC current components at the output during DC-AC conversion.

Optimization of Single Point Incremental Forming of Al5052-O Sheet

Energy Technology Data Exchange (ETDEWEB)

Kim, Chan Il; Xiao, Xiao; Do, Van Cuong; Kim, Young Suk [Kyungpook Nat’l Univ., Daegu (Korea, Republic of)

2017-03-15

Single point incremental forming (SPIF) is a sheet-forming technique. It is a die-less sheet metal manufacturing process for rapid prototyping and small batch production. The Critical parameters in the forming process include tool diameter, step depth, feed rate, spindle speed, etc. In this study, these parameters and the die shape corresponding to the Varying Wall Angle Conical Frustum(VWACF) model were used for forming 0.8mm in thick Al5052-O sheets. The Taguchi method of Experiments of Design (DOE) and Grey relational optimization were used to determine the optimum parameters in SPIF. A response study was performed on formability, spring back, and thickness reduction. The research shows that the optimum combination of these parameters that yield best performance of SPIF is as follows: tool diameter, 6mm; spin speed, 60rpm; step depth, 0.3mm; and feed rate, 500mm/min.

[Hypothesis on the equilibrium point and variability of amplitude, speed and time of single-joint movement].

Science.gov (United States)

Latash, M; Gottleib, G

1990-01-01

Problems of single-joint movement variability are analysed in the framework of the equilibrium-point hypothesis (the lambda-model). Control of the movements is described with three parameters related to movement amplitude speed, and time. Three strategies emerge from this description. Only one of them is likely to lead to a Fitts' type speed-accuracy trade-off. Experiments were performed to test one of the predictions of the model. Subjects performed identical sets of single-joint fast movements with open or closed eyes and some-what different instructions. Movements performed with closed eyes were characterized with higher peak speeds and unchanged variability in seeming violation of the Fitt's law and in a good correspondence to the model.

Structure Based Thermostability Prediction Models for Protein Single Point Mutations with Machine Learning Tools.

Directory of Open Access Journals (Sweden)

Lei Jia

Full Text Available Thermostability issue of protein point mutations is a common occurrence in protein engineering. An application which predicts the thermostability of mutants can be helpful for guiding decision making process in protein design via mutagenesis. An in silico point mutation scanning method is frequently used to find "hot spots" in proteins for focused mutagenesis. ProTherm (http://gibk26.bio.kyutech.ac.jp/jouhou/Protherm/protherm.html is a public database that consists of thousands of protein mutants' experimentally measured thermostability. Two data sets based on two differently measured thermostability properties of protein single point mutations, namely the unfolding free energy change (ddG and melting temperature change (dTm were obtained from this database. Folding free energy change calculation from Rosetta, structural information of the point mutations as well as amino acid physical properties were obtained for building thermostability prediction models with informatics modeling tools. Five supervised machine learning methods (support vector machine, random forests, artificial neural network, naïve Bayes classifier, K nearest neighbor and partial least squares regression are used for building the prediction models. Binary and ternary classifications as well as regression models were built and evaluated. Data set redundancy and balancing, the reverse mutations technique, feature selection, and comparison to other published methods were discussed. Rosetta calculated folding free energy change ranked as the most influential features in all prediction models. Other descriptors also made significant contributions to increasing the accuracy of the prediction models.

Sensor system for multi-point monitoring using bending loss of single mode optical fiber

International Nuclear Information System (INIS)

Kim, Heon Young; Kim, Dae Hyun

2015-01-01

Applications of smart sensors have been extended to safety systems in the aerospace, transportation and civil engineering fields. In particular, structural health monitoring techniques using smart sensors have gradually become necessary and have been developed to prevent dangers to human life and damage to assets. Generally, smart sensors are based on electro-magnets and have several weaknesses, including electro-magnetic interference and distortion. Therefore, fiber optic sensors are an outstanding alternative to overcome the weaknesses of electro-magnetic sensors. However, they require expensive devices and complex systems. This paper proposes a new, affordable and simple sensor system that uses a single fiber to monitor pressures at multiple-points. Moreover, a prototype of the sensor system was manufactured and tested for a feasibility study. Based on the results of this experimental test, a relationship was carefully observed between the bend loss conditions and light-intensity. As a result, it was shown that impacts at multiple-points could be monitored.

An ultra-precision tool nanoindentation instrument for replication of single point diamond tool cutting edges

Science.gov (United States)

Cai, Yindi; Chen, Yuan-Liu; Xu, Malu; Shimizu, Yuki; Ito, So; Matsukuma, Hiraku; Gao, Wei

2018-05-01

Precision replication of the diamond tool cutting edge is required for non-destructive tool metrology. This paper presents an ultra-precision tool nanoindentation instrument designed and constructed for replication of the cutting edge of a single point diamond tool onto a selected soft metal workpiece by precisely indenting the tool cutting edge into the workpiece surface. The instrument has the ability to control the indentation depth with a nanometric resolution, enabling the replication of tool cutting edges with high precision. The motion of the diamond tool along the indentation direction is controlled by the piezoelectric actuator of a fast tool servo (FTS). An integrated capacitive sensor of the FTS is employed to detect the displacement of the diamond tool. The soft metal workpiece is attached to an aluminum cantilever whose deflection is monitored by another capacitive sensor, referred to as an outside capacitive sensor. The indentation force and depth can be accurately evaluated from the diamond tool displacement, the cantilever deflection and the cantilever spring constant. Experiments were carried out by replicating the cutting edge of a single point diamond tool with a nose radius of 2.0 mm on a copper workpiece surface. The profile of the replicated tool cutting edge was measured using an atomic force microscope (AFM). The effectiveness of the instrument in precision replication of diamond tool cutting edges is well-verified by the experimental results.

Shape measurement system for single point incremental forming (SPIF) manufacts by using trinocular vision and random pattern

International Nuclear Information System (INIS)

Setti, Francesco; Bini, Ruggero; Lunardelli, Massimo; Bosetti, Paolo; Bruschi, Stefania; De Cecco, Mariolino

2012-01-01

Many contemporary works show the interest of the scientific community in measuring the shape of artefacts made by single point incremental forming. In this paper, we will present an algorithm able to detect feature points with a random pattern, check the compatibility of associations exploiting multi-stereo constraints and reject outliers and perform a 3D reconstruction by dense random patterns. The algorithm is suitable for a real-time application, in fact it needs just three images and a synchronous relatively fast processing. The proposed method has been tested on a simple geometry and results have been compared with a coordinate measurement machine acquisition. (paper)

Probing Critical Point Energies of Transition Metal Dichalcogenides: Surprising Indirect Gap of Single Layer WSe 2

KAUST Repository

Zhang, Chendong; Chen, Yuxuan; Johnson, Amber; Li, Ming-yang; Li, Lain-Jong; Mende, Patrick C.; Feenstra, Randall M.; Shih, Chih Kang

2015-01-01

By using a comprehensive form of scanning tunneling spectroscopy, we have revealed detailed quasi-particle electronic structures in transition metal dichalcogenides, including the quasi-particle gaps, critical point energy locations, and their origins in the Brillouin zones. We show that single layer WSe surprisingly has an indirect quasi-particle gap with the conduction band minimum located at the Q-point (instead of K), albeit the two states are nearly degenerate. We have further observed rich quasi-particle electronic structures of transition metal dichalcogenides as a function of atomic structures and spin-orbit couplings. Such a local probe for detailed electronic structures in conduction and valence bands will be ideal to investigate how electronic structures of transition metal dichalcogenides are influenced by variations of local environment.

Probing Critical Point Energies of Transition Metal Dichalcogenides: Surprising Indirect Gap of Single Layer WSe 2

KAUST Repository

Zhang, Chendong

2015-09-21

By using a comprehensive form of scanning tunneling spectroscopy, we have revealed detailed quasi-particle electronic structures in transition metal dichalcogenides, including the quasi-particle gaps, critical point energy locations, and their origins in the Brillouin zones. We show that single layer WSe surprisingly has an indirect quasi-particle gap with the conduction band minimum located at the Q-point (instead of K), albeit the two states are nearly degenerate. We have further observed rich quasi-particle electronic structures of transition metal dichalcogenides as a function of atomic structures and spin-orbit couplings. Such a local probe for detailed electronic structures in conduction and valence bands will be ideal to investigate how electronic structures of transition metal dichalcogenides are influenced by variations of local environment.

Fabrication of an infrared Shack-Hartmann sensor by combining high-speed single-point diamond milling and precision compression molding processes.

Science.gov (United States)

Zhang, Lin; Zhou, Wenchen; Naples, Neil J; Yi, Allen Y

2018-05-01

A novel fabrication method by combining high-speed single-point diamond milling and precision compression molding processes for fabrication of discontinuous freeform microlens arrays was proposed. Compared with slow tool servo diamond broaching, high-speed single-point diamond milling was selected for its flexibility in the fabrication of true 3D optical surfaces with discontinuous features. The advantage of single-point diamond milling is that the surface features can be constructed sequentially by spacing the axes of a virtual spindle at arbitrary positions based on the combination of rotational and translational motions of both the high-speed spindle and linear slides. By employing this method, each micro-lenslet was regarded as a microstructure cell by passing the axis of the virtual spindle through the vertex of each cell. An optimization arithmetic based on minimum-area fabrication was introduced to the machining process to further increase the machining efficiency. After the mold insert was machined, it was employed to replicate the microlens array onto chalcogenide glass. In the ensuing optical measurement, the self-built Shack-Hartmann wavefront sensor was proven to be accurate in detecting an infrared wavefront by both experiments and numerical simulation. The combined results showed that precision compression molding of chalcogenide glasses could be an economic and precision optical fabrication technology for high-volume production of infrared optics.

The Progress in Clinical and Basic Research of the Effect ofAcupuncture in Treating Disorders of Gastrointestinal Motility

Institute of Scientific and Technical Information of China (English)

无

2000-01-01

Though the function of “spleen” in TCM refers to a lot of systems, it is mainly related to digestive system, reflecting changes of physiology and pathology of gastrointestinal tract. The deficiency of Spleen Qi is correlated to the disorders of gastrointestinal motility.(19) In recent years the research has been developed in adjustment of Spleen and Stomach function and the improvement of gastrointestinal motility by acupuncturing mainly Zusanli, which formed a theoretic base for acupuncture therapy of disorders of gastrointestinal motility.Effect of Acupuncture on Gastric Peristalsis　　Observation by gastroendoscopy and B-ultrasonography showed that, acupuncture at Zusanli could decrease gastric tension and resolve spasm of cardia, gastric body and pylorus, and improve delayed opening of pylorus, so as to make gastric hyperperistalsis tend to go placid and normalize retarding. It is demonstrated that acupuncture at Zusanli could adjust the function of gastric peristalsis bi-directionally.(20,21) In healthy volunteers after acupuncture at Zusanli the frequency and the amplititude of gastric peristalsis both increased. In patients whose pylorus ring could not open during the operation of gastroscopy, acupuncture at Zusanli could relax and open it. Acupuncture at Neiguan could produce either opening or closing the bi-directional effect of pylorus.(22) In patients with disorders of gastrointestinal motility it was observed that the amplititude and frequency of constriction of sphincter pylori increased and the strength and frequency of stomach improved after acupuncture at Zusanli according to the measurement of gastroscopic manometry.(23) Acupuncture may accelerate or reduce the speed of gastric evacuation.(24,25) In addition, acupuncture can increase the volume of gastric antrum. Observed by B-ultrasonography, acupuncture Zusanli, Shangjuxu (ST37), Chongyang (ST42) and Neiting (ST44) in the lower extremity section of the Yangming meridian of the foot could

Analysis of Point Based Image Registration Errors With Applications in Single Molecule Microscopy.

Science.gov (United States)

Cohen, E A K; Ober, R J

2013-12-15

We present an asymptotic treatment of errors involved in point-based image registration where control point (CP) localization is subject to heteroscedastic noise; a suitable model for image registration in fluorescence microscopy. Assuming an affine transform, CPs are used to solve a multivariate regression problem. With measurement errors existing for both sets of CPs this is an errors-in-variable problem and linear least squares is inappropriate; the correct method being generalized least squares. To allow for point dependent errors the equivalence of a generalized maximum likelihood and heteroscedastic generalized least squares model is achieved allowing previously published asymptotic results to be extended to image registration. For a particularly useful model of heteroscedastic noise where covariance matrices are scalar multiples of a known matrix (including the case where covariance matrices are multiples of the identity) we provide closed form solutions to estimators and derive their distribution. We consider the target registration error (TRE) and define a new measure called the localization registration error (LRE) believed to be useful, especially in microscopy registration experiments. Assuming Gaussianity of the CP localization errors, it is shown that the asymptotic distribution for the TRE and LRE are themselves Gaussian and the parameterized distributions are derived. Results are successfully applied to registration in single molecule microscopy to derive the key dependence of the TRE and LRE variance on the number of CPs and their associated photon counts. Simulations show asymptotic results are robust for low CP numbers and non-Gaussianity. The method presented here is shown to outperform GLS on real imaging data.

Influence of Fiber Orientation on Single-Point Cutting Fracture Behavior of Carbon-Fiber/Epoxy Prepreg Sheets

OpenAIRE

Wei, Yingying; An, Qinglong; Cai, Xiaojiang; Chen, Ming; Ming, Weiwei

2015-01-01

The purpose of this article is to investigate the influences of carbon fibers on the fracture mechanism of carbon fibers both in macroscopic view and microscopic view by using single-point flying cutting method. Cutting tools with three different materials were used in this research, namely, PCD (polycrystalline diamond) tool, CVD (chemical vapor deposition) diamond thin film coated carbide tool and uncoated carbide tool. The influence of fiber orientation on the cutting force and fracture to...

Improving Gastric Cancer Outcome Prediction Using Single Time-Point Artificial Neural Network Models

Science.gov (United States)

Nilsaz-Dezfouli, Hamid; Abu-Bakar, Mohd Rizam; Arasan, Jayanthi; Adam, Mohd Bakri; Pourhoseingholi, Mohamad Amin

2017-01-01

In cancer studies, the prediction of cancer outcome based on a set of prognostic variables has been a long-standing topic of interest. Current statistical methods for survival analysis offer the possibility of modelling cancer survivability but require unrealistic assumptions about the survival time distribution or proportionality of hazard. Therefore, attention must be paid in developing nonlinear models with less restrictive assumptions. Artificial neural network (ANN) models are primarily useful in prediction when nonlinear approaches are required to sift through the plethora of available information. The applications of ANN models for prognostic and diagnostic classification in medicine have attracted a lot of interest. The applications of ANN models in modelling the survival of patients with gastric cancer have been discussed in some studies without completely considering the censored data. This study proposes an ANN model for predicting gastric cancer survivability, considering the censored data. Five separate single time-point ANN models were developed to predict the outcome of patients after 1, 2, 3, 4, and 5 years. The performance of ANN model in predicting the probabilities of death is consistently high for all time points according to the accuracy and the area under the receiver operating characteristic curve. PMID:28469384

Femtosecond few- to single-electron point-projection microscopy for nanoscale dynamic imaging

Directory of Open Access Journals (Sweden)

A. R. Bainbridge

2016-03-01

Full Text Available Femtosecond electron microscopy produces real-space images of matter in a series of ultrafast snapshots. Pulses of electrons self-disperse under space-charge broadening, so without compression, the ideal operation mode is a single electron per pulse. Here, we demonstrate femtosecond single-electron point projection microscopy (fs-ePPM in a laser-pump fs-e-probe configuration. The electrons have an energy of only 150 eV and take tens of picoseconds to propagate to the object under study. Nonetheless, we achieve a temporal resolution with a standard deviation of 114 fs (equivalent to a full-width at half-maximum of 269 ± 40 fs combined with a spatial resolution of 100 nm, applied to a localized region of charge at the apex of a nanoscale metal tip induced by 30 fs 800 nm laser pulses at 50 kHz. These observations demonstrate real-space imaging of reversible processes, such as tracking charge distributions, is feasible whilst maintaining femtosecond resolution. Our findings could find application as a characterization method, which, depending on geometry, could resolve tens of femtoseconds and tens of nanometres. Dynamically imaging electric and magnetic fields and charge distributions on sub-micron length scales opens new avenues of ultrafast dynamics. Furthermore, through the use of active compression, such pulses are an ideal seed for few-femtosecond to attosecond imaging applications which will access sub-optical cycle processes in nanoplasmonics.

Comparative MR study of hepatic fat quantification using single-voxel proton spectroscopy, two-point dixon and three-point IDEAL.

Science.gov (United States)

Kim, Hyeonjin; Taksali, Sara E; Dufour, Sylvie; Befroy, Douglas; Goodman, T Robin; Petersen, Kitt Falk; Shulman, Gerald I; Caprio, Sonia; Constable, R Todd

2008-03-01

Hepatic fat fraction (HFF) was measured in 28 lean/obese humans by single-voxel proton spectroscopy (MRS), a two-point Dixon (2PD), and a three-point iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) method (3PI). For the lean, obese, and total subject groups, the range of HFF measured by MRS was 0.3-3.5% (1.1 +/- 1.4%), 0.3-41.5% (11.7 +/- 12.1), and 0.3-41.5% (10.1 +/- 11.6%), respectively. For the same groups, the HFF measured by 2PD was -6.3-2.2% (-2.0 +/- 3.7%), -2.4-42.9% (12.9 +/- 13.8%), and -6.3-42.9% (10.5 +/- 13.7%), respectively, and for 3PI they were 7.9-12.8% (10.1 +/- 2.0%), 11.1-49.3% (22.0 +/- 12.2%), and 7.9-49.3% (20.0 +/- 11.8%), respectively. The HFF measured by MRS was highly correlated with those measured by 2PD (r = 0.954, P fatty liver with the MRI methods ranged from 68-93% for 2PD and 64-89% for 3PI. Our study demonstrates that the apparent HFF measured by the MRI methods can significantly vary depending on the choice of water-fat separation methods and sequences. Such variability may limit the clinical application of the MRI methods, particularly when a diagnosis of early fatty liver needs to be performed. Therefore, protocol-specific establishment of cutoffs for liver fat content may be necessary. (c) 2008 Wiley-Liss, Inc.

Performance evaluation of thermally treated graphite felt electrodes for vanadium redox flow battery and their four-point single cell characterization

Science.gov (United States)

Mazúr, P.; Mrlík, J.; Beneš, J.; Pocedič, J.; Vrána, J.; Dundálek, J.; Kosek, J.

2018-03-01

In our contribution we study the electrocatalytic effect of oxygen functionalization of thermally treated graphite felt on kinetics of electrode reactions of vanadium redox flow battery. Chemical and morphological changes of the felts are analysed by standard physico-chemical characterization techniques. A complex method four-point method is developed and employed for characterization of the felts in a laboratory single-cell. The method is based on electrochemical impedance spectroscopy and load curves measurements of positive and negative half-cells using platinum wire pseudo-reference electrodes. The distribution of ohmic and faradaic losses within a single-cell is evaluated for both symmetric and asymmetric electrode set-up with respect to the treatment conditions. Positive effect of oxygen functionalization is observed only for negative electrode, whereas kinetics of positive electrode reaction is almost unaffected by the treatment. This is in a contradiction to the results of typically employed cyclovoltammetric characterization which indicate that both electrodes are enhanced by the treatment to a similar extent. The developed four-point characterization method can be further used e.g., for the component screening and in-situ durability studies on single-cell scale redox flow batteries of various chemistries.

Phase transitions and multicritical points in the mixed spin-32 and spin-2 Ising system with a single-ion anisotropy

International Nuclear Information System (INIS)

Bobak, A.; Dely, J.

2007-01-01

The effect of a single-ion anisotropy on the phase diagram of the mixed spin-32 and spin-2 Ising system is investigated by the use of a mean-field theory based on the Bogoliubov inequality for the free energy. Topologically different kinds of phase diagrams are achieved by changing values of the parameter in the model Hamiltonian. Besides second-order transitions, lines of first-order transitions terminating either at a tricritical point or an isolated critical point, are found

The superconducting gaps of C-substituted and Al-substituted MgB2 single crystals by point-contact spectroscopy

International Nuclear Information System (INIS)

Daghero, D.; Gonnelli, R.S.; Ummarino, G.A.; Calzolari, A.; Dellarocca, Valeria; Stepanov, V.A.; Zhigadlo, N.; Kazakov, S.M.; Karpinski, J.

2005-01-01

We studied the effects of carbon and aluminum substitutions on the gaps of the two-band superconductor MgB 2 by means of point-contact measurements in Mg(B 1-x C x ) 2 and Mg 1-y Al y B 2 single crystals with 0≤x≤0.132 and 0≤y≤0.21. The gap amplitudes, Δ ω and Δ π , were determined by fitting the conductance curves of the point contacts with the standard Blonder-Tinkham-Klapwijk (BTK) model generalized to the two-band case. Whenever possible, their values were confirmed by the independent fit (with a single-band BTK model) of the partial contribution of the two bands to the conductance, separated by means of a suitable magnetic field B*. In C-substituted crystals, the two gaps remain clearly distinct up to x∝0.10, but at x=0.132 we observed for the first time their merging into a single gap Δ≅3 meV with a gap ratio 2Δ=k B T c close to the standard BCS value. In Al-substituted crystals, we found no evidence of this gap merging. Instead, Δ π reaches the value 0.4 meV at y=0.21, where Δ π saturates at about 4 meV. These results are compared with other recent experimental findings in polycrystals and with the predictions of the models for multiband superconductivity. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Spherical Projection Based Straight Line Segment Extraction for Single Station Terrestrial Laser Point Cloud

Directory of Open Access Journals (Sweden)

ZHANG Fan

2015-06-01

Full Text Available Due to the discrete distribution computing errors and lack of adaptability are ubiquitous in the current straight line extraction for TLS data methods. A 3D straight line segment extraction method is proposed based on spherical projection for single station terrestrial laser point clouds. Firstly, horizontal and vertical angles of each laser point are calculated by means of spherical coordinates, intensity panoramic image according to the two angles is generated. Secondly, edges which include straight line features are detected from intensity panoramic image by using of edge detection algorithm. Thirdly, great circles are detected from edges of panoramic image using spherical Hough transform. According to the axiom that a straight line segment in 3D space is a spherical great circle after spherical projection, detecting great circles from spherical projected data sets is essentially detecting straight line segments from 3D data sets without spherical projection. Finally, a robust 3D straight line fitting method is employed to fitting the straight lines and calculating parameters of the straight line segments. Experiments using different data sets and comparison with other methods show the accuracy and applicability of the proposed method.

Repetitive Acupuncture Point Treatment with Diluted Bee Venom Relieves Mechanical Allodynia and Restores Intraepidermal Nerve Fiber Loss in Oxaliplatin-Induced Neuropathic Mice.

Science.gov (United States)

Yeo, Ji-Hee; Yoon, Seo-Yeon; Kwon, Soon-Keun; Kim, Sol-Ji; Lee, Jang-Hern; Beitz, Alvin J; Roh, Dae-Hyun

2016-03-01

The chemotherapeutic agent, oxaliplatin, produces a robust painful neuropathy that results in the loss of intraepidermal nerve fibers (IENFs). We have previously reported that an acupuncture point (acupoint) injection of diluted bee venom (DBV) produces a temporary antiallodynic effect in oxaliplatin-induced neuropathic mice. Herein we show a significant long-lasting antinociceptive effect of repetitive DBV acupoint treatment on oxaliplatin-induced mechanical allodynia and a significant reduction in the loss of IENFs. DBV (0.1 mg/kg, subcutaneous) was administered once a day for 18 days beginning on day 15 after oxaliplatin injection. Immunohistochemistry for IENF was performed on the glabrous skin of the hind paw footpad using the pan-neuronal marker, protein gene product 9.5. A temporary increase in mechanical threshold was observed 60 minutes after a single DBV injection into the Zusanli acupoint, and this effect was enhanced over time with repetitive DBV treatments. The basal mechanical threshold before daily DBV injection also increased from day 7 after DBV injections, and peaked at day 14 after DBV treatment. Moreover, the oxaliplatin-induced loss of IENFs was significantly reduced in mice treated repetitively with DBV. Repetitive pretreatment with the α-2 adrenoceptor antagonist, yohimbine, (5 mg/kg, subcutaneous) completely prevented the antiallodynic effects and the increase in IENFs observed in mice treated repetitively with DBV. We showed that repetitive acupoint stimulation with DBV gradually and significantly reduced oxaliplatin-induced mechanical allodynia and restored the loss of IENFs in neuropathic mice via an α-2 adrenoceptor mechanism. Collectively, results of this study suggest that repetitive acupoint treatment with DBV can be a potential strategy for the management of chemotherapy-induced neuropathy. Copyright © 2016 American Pain Society. Published by Elsevier Inc. All rights reserved.

SU-E-T-263: Point Dose Variation Using a Single Ir-192 HDR Brachytherapy Plan for Two Treatments with a Single Tandem-Ovoid Insertion for Cervical Cancer

Energy Technology Data Exchange (ETDEWEB)

Liang, X; Morrill, S; Hardee, M; Han, E; Penagaricano, J; Zhang, X; Vaneerat, R [University of Arkansas Medical Science, Little Rock, AR (United States)

2014-06-01

Purpose: To evaluate the point dose variations between Ir-192 HDR treatments on two consecutive days using a single tandem-ovoid insertion without replanning in cervical cancer patients. Methods: This study includes eleven cervical cancer patients undergoing HDR brachytherapy with a prescribed dose of 28 Gy in 4 fractions. Each patient had two tandemovoid insertions one week apart. Each insertion was treated on consecutive days with rescanning and replanning prior to each treatment. To study the effect of no replanning for day 2 treatments, the day 1 plan dwell position and dwell time with decay were applied to the day 2 CT dataset. The point dose variations on the prescription point H (defined according to American Brachytherapy Society), and normal tissue doses at point B, bladder, rectum and vaginal mucosa (based on ICRU Report 38) were obtained. Results: Without replanning, the mean point H dose variation was 4.6 ± 10.7% on the left; 2.3 ± 2.9% on the right. The mean B point variation was 3.8 ± 4.9% on the left; 3.6 ± 4.7% on the right. The variation in the left vaginal mucosal point was 12.2 ± 10.7%; 9.5 ± 12.5% on the right; the bladder point 5.5 ± 7.4%; and the rectal point 7.9 ± 9.1%. Conclusion: Without replanning, there are variations both in the prescription point and the normal tissue point doses. The latter can vary as much as 10% or more. This is likely due to the steep dose gradient from brachytherapy compounded by shifts in the positions of the applicator in relationship to the patients anatomy. Imaging prior to each treatment and replanning ensure effective and safe brachytherapy are recommended.

Channel capacity of TDD-OFDM-MIMO for multiple access points in a wireless single-frequency-network

DEFF Research Database (Denmark)

Takatori, Y.; Fitzek, Frank; Tsunekawa, K.

2005-01-01

MIMO data transmission scheme, which combines Single-Frequency-Network (SFN) with TDD-OFDM-MIMO applied for wireless LAN networks. In our proposal, we advocate to use SFN for multiple access points (MAP) MIMO data transmission. The goal of this approach is to achieve very high channel capacity in both......The multiple-input-multiple-output (MIMO) technique is the most attractive candidate to improve the spectrum efficiency in the next generation wireless communication systems. However, the efficiency of MIMO techniques reduces in the line of sight (LOS) environments. In this paper, we propose a new...

Investigating the use of multi-point coupling for single-sensor bearing estimation in one direction

Science.gov (United States)

Woolard, Americo G.; Phoenix, Austin A.; Tarazaga, Pablo A.

2018-04-01

Bearing estimation of radially propagating symmetric waves in solid structures typically requires a minimum of two sensors. As a test specimen, this research investigates the use of multi-point coupling to provide directional inference using a single-sensor. By this provision, the number of sensors required for localization can be reduced. A finite-element model of a beam is constructed with a symmetrically placed bipod that has asymmetric joint-stiffness properties. Impulse loading is applied at different points along the beam, and measurements are taken from the apex of the bipod. A technique is developed to determine the direction-of-arrival of the propagating wave. The accuracy when using the bipod with the developed technique is compared against results gathered without the bipod and measuring from an asymmetric location along the beam. The results show 92% accuracy when the bipod is used, compared to 75% when measuring without the bipod from an asymmetric location. A geometry investigation finds the best accuracy results when one leg of the bipod has a low stiffness and a large diameter relative to the other leg.

Chaos analysis of the electrical signal time series evoked by acupuncture

International Nuclear Information System (INIS)

Wang Jiang; Sun Li; Fei Xiangyang; Zhu Bing

2007-01-01

This paper employs chaos theory to analyze the time series of electrical signal which are evoked by different acupuncture methods applied to the Zusanli point. The phase space is reconstructed and the embedding parameters are obtained by the mutual information and Cao's methods. Subsequently, the largest Lyapunov exponent is calculated. From the analyses we can conclude that the time series are chaotic. In addition, differences between various acupuncture methods are discussed

[Efficacy on hemiplegic spasticity treated with plum blossom needle tapping therapy at the key points and Bobath therapy: a randomized controlled trial].

Science.gov (United States)

Wang, Fei; Zhang, Lijuan; Wang, Jianhua; Shi, Yan; Zheng, Liya

2015-08-01

To evaluate the efficacy on hemiplegic spasticity after cerebral infarction treated with plum blossom needle tapping therapy at the key points and Bobath therapy. Eighty patients were collected, in compliance with the inclusive criteria of hemiplegic spasticity after cerebral infarction, and randomized into an observation group and a control group, 40 cases in each one. In the control group, Bobath manipulation therapy was adopted to relieve spasticity and the treatment of 8 weeks was required. In the observation group, on the basis of the treatment as the control group, the tapping therapy with plum blossom needle was applied to the key points, named Jianyu (LI 15), Jianliao (LI 14), Jianzhen (SI 9), Hegu (LI 4), Chengfu (BL 36), Zusanli (ST 36), Xiyangguan (GB 33), etc. The treatment was given for 15 min each time, once a day. Before treatment, after 4 and 8 weeks of treatment, the Fugl-Meyer assessment (FMA) and Barthel index (BI) were adopted to evaluate the motor function of the extremity and the activity of daily life in the patients of the two groups separately. The modified Ashworth scale was used to evaluate the effect of anti-spasticity. In 4 and 8 weeks of treatment, FMA: scores and BI scores were all significantly increased as compared with those before treatment in the two groups: (both PBobath therapy effectively relieves hemiplegic spasticity in the patients of cerebral infarction and improves the motor function of extremity and the activity of daily life.

Single gaze gestures

DEFF Research Database (Denmark)

Møllenbach, Emilie; Lilholm, Martin; Gail, Alastair

2010-01-01

This paper examines gaze gestures and their applicability as a generic selection method for gaze-only controlled interfaces. The method explored here is the Single Gaze Gesture (SGG), i.e. gestures consisting of a single point-to-point eye movement. Horizontal and vertical, long and short SGGs were...

Criteria for evaluating protection from single points of failure for partially expanded fault trees

International Nuclear Information System (INIS)

Aswani, D.; Badreddine, B.; Malone, M.; Gauthier, G.; Proietty, J.

2008-01-01

Fault tree analysis (FTA) is a technique that describes the combinations of events in a system which result in an undesirable outcome. FTA is used as a tool to quantitatively assess a system's probability for an undesirable outcome. Time constraints from concept to production in modern engineering often limit the opportunity for a thorough statistical analysis of a system. Furthermore, when undesirable outcomes are considered such as hazard to human(s), it becomes difficult to identify strict statistical targets for what is acceptable. Consequently, when hazard to human(s) is concerned a common design target is to protect the system from single points of failure (SPOF) which means that no failure mode caused by a single event, concern, or error has a critical consequence on the system. Such a design target is common with 'by-wire' systems. FTA can be used to verify if a system is protected from SPOF. In this paper, sufficient criteria for evaluating protection from SPOF for partially expanded fault trees are proposed along with proof. The proposed criteria consider potential interactions between the lowest drawn events of a partial fault tree expansion which otherwise easily leads to an overly optimistic analysis of protection from SPOF. The analysis is limited to fault trees that are coherent and static

Improving access in gastroenterology: The single point of entry model for referrals

Science.gov (United States)

Novak, Kerri L; Van Zanten, Sander Veldhuyzen; Pendharkar, Sachin R

2013-01-01

In 2005, a group of academic gastroenterologists in Calgary (Alberta) adopted a centralized referral intake system known as central triage. This system provided a single point of entry model (SEM) for referrals rather than the traditional system of individual practitioners managing their own referrals and queues. The goal of central triage was to improve wait times and referral management. In 2008, a similar system was developed in Edmonton at the University of Alberta Hospital (Edmonton, Alberta). SEMs have subsequently been adopted by numerous subspecialties throughout Alberta. There are many benefits of SEMs including improved access and reduced wait times. Understanding and measuring complex patient flow systems is key to improving access, and centralized intake systems provide an opportunity to better understand total demand and system bottlenecks. This knowledge is particularly important for specialties such as gastroenterology (GI), in which demand exceeds supply. While it is anticipated that SEMs will reduce wait times for GI care in Canada, the lack of sufficient resources to meet the demand for GI care necessitates additional strategies. PMID:24040629

Improving Access in Gastroenterology: The Single Point of Entry Model for Referrals

Directory of Open Access Journals (Sweden)

Kerri L Novak

2013-01-01

Full Text Available In 2005, a group of academic gastroenterologists in Calgary (Alberta adopted a centralized referral intake system known as central triage. This system provided a single point of entry model (SEM for referrals rather than the traditional system of individual practitioners managing their own referrals and queues. The goal of central triage was to improve wait times and referral management. In 2008, a similar system was developed in Edmonton at the University of Alberta Hospital (Edmonton, Alberta. SEMs have subsequently been adopted by numerous subspecialties throughout Alberta. There are many benefits of SEMs including improved access and reduced wait times. Understanding and measuring complex patient flow systems is key to improving access, and centralized intake systems provide an opportunity to better understand total demand and system bottlenecks. This knowledge is particularly important for specialties such as gastroenterology (GI, in which demand exceeds supply. While it is anticipated that SEMs will reduce wait times for GI care in Canada, the lack of sufficient resources to meet the demand for GI care necessitates additional strategies.

Improving access in gastroenterology: the single point of entry model for referrals.

Science.gov (United States)

Novak, Kerri; Veldhuyzen Van Zanten, Sander; Pendharkar, Sachin R

2013-11-01

In 2005, a group of academic gastroenterologists in Calgary (Alberta) adopted a centralized referral intake system known as central triage. This system provided a single point of entry model (SEM) for referrals rather than the traditional system of individual practitioners managing their own referrals and queues. The goal of central triage was to improve wait times and referral management. In 2008, a similar system was developed in Edmonton at the University of Alberta Hospital (Edmonton, Alberta). SEMs have subsequently been adopted by numerous subspecialties throughout Alberta. There are many benefits of SEMs including improved access and reduced wait times. Understanding and measuring complex patient flow systems is key to improving access, and centralized intake systems provide an opportunity to better understand total demand and system bottlenecks. This knowledge is particularly important for specialties such as gastroenterology (GI), in which demand exceeds supply. While it is anticipated that SEMs will reduce wait times for GI care in Canada, the lack of sufficient resources to meet the demand for GI care necessitates additional strategies.

MRI of hip prostheses using single-point methods : in vitro studies towards the artifact-free imaging of individuals with metal implants

NARCIS (Netherlands)

Ramos Cabrer, P.; Duynhoven, van J.P.M.; Toorn, van der A.; Nicolaij, K.

2004-01-01

Use of magnetic resonance imaging (MRI) in individuals with orthopedic implants is limited because of the large distortions caused by metallic components. As a possible solution for this problem, we suggest the use of single-point imaging (SPI) methods, which are immune to the susceptibility

Uncertainty analysis of point by point sampling complex surfaces using touch probe CMMs

DEFF Research Database (Denmark)

Barini, Emanuele; Tosello, Guido; De Chiffre, Leonardo

2007-01-01

The paper describes a study concerning point by point scanning of complex surfaces using tactile CMMs. A four factors-two level full factorial experiment was carried out, involving measurements on a complex surface configuration item comprising a sphere, a cylinder and a cone, combined in a singl...

Comparison of clinical outcomes of multi-point umbrella suturing and single purse suturing with two-point traction after procedure for prolapse and hemorrhoids (PPH) surgery.

Science.gov (United States)

Jiang, Huiyong; Hao, Xiuyan; Xin, Ying; Pan, Youzhen

2017-11-01

To compare the clinical outcomes of multipoint umbrella suture and single-purse suture with two-point traction after procedure for prolapse and hemorrhoids surgery (PPH) for the treatment of mixed hemorrhoids. Ninety patients were randomly divided into a PPH plus single-purse suture group (Group A) and a PPH plus multipoint umbrella suture (Group B). All operations were performed by an experienced surgeon. Operation time, width of the specimen, hemorrhoids retraction extent, postoperative pain, postoperative bleeding, and length of hospitalization were recorded and compared. Statistical analysis was conducted by t-test and χ2 test. There were no significant differences in sex, age, course of disease, and degree of prolapse of hemorrhoids between the two groups. The operative time in Group A was significantly shorter than that in Group B (P hemorrhoid core retraction were significantly lower in Group B (P  0.05 for all comparisons) was observed. The multipoint umbrella suture showed better clinical outcomes because of its targeted suture according to the extent of hemorrhoid prolapse. Copyright © 2017. Published by Elsevier Ltd.

A single point mutation in Tomato spotted wilt virus NSs protein is sufficient to overcome Tsw-gene-mediated resistance in pepper.

Science.gov (United States)

Almási, Asztéria; Nemes, Katalin; Csömör, Zsófia; Tóbiás, István; Palkovics, László; Salánki, Katalin

2017-06-01

The nonstructural protein (NSs) of Tomato spotted wilt virus (TSWV) was previously identified as an avirulence determinant for Tsw-based resistance on pepper. The NSs of wild-type (WT) and resistance-breaking (RB) TSWV strains isolated in Hungary had only two amino acid substitutions (104, 461). We have analysed the ability of the NSs and their point mutant variants to trigger Tsw-mediated hypersensitive responses and RNA silencing suppressor (RSS) activity in patch assays. We identified a single amino acid change at position 104 (T-A) that was responsible for the necrosis induction or loss, while a significant difference was not detected in the RSS activity of the two parental strains. We have successfully complemented the infection of the WT strain on resistant pepper cultivar with the infectious S RNA transcript of the RB strain and the WT-T104A point mutant. Our work provides direct evidence that a single amino acid change can induce an RB phenotype.

A Comparative MR Study of Hepatic Fat Quantification Using Single-voxel Proton Spectroscopy, Two-point Dixon and Three-point IDEAL

Science.gov (United States)

Kim, Hyeonjin; Taksali, Sara E.; Dufour, Sylvie; Befroy, Douglas; Goodman, T. Robin; Petersen, Kitt Falk; Shulman, Gerald I.; Caprio, Sonia; Constable, R. Todd

2009-01-01

Hepatic fat fraction (HFF) was measured in 28 lean/obese humans by single-voxel proton spectroscopy (MRS), a two-point Dixon (2PD) and a three-point iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) method (3PI). For the lean, obese and total subject groups, the range of HFF measured by MRS was 0.3–3.5% (1.1±1.4%), 0.3–41.5% (11.7±12.1), and 0.3–41.5% (10.1±11.6%), respectively For the same groups, the HFF measured by 2PD was −6.3–2.2% (−2.0±3.7%), −2.4–42.9% (12.9±13.8%), and −6.3–42.9% (10.5±13.7%), respectively, and for 3PI they were 7.9–12.8% (10.1±2.0%), 11.1–49.3% (22.0±12.2%), and 7.9–49.3% (20.0±11.8%), respectively. The HFF measured by MRS was highly correlated with those measured by 2PD (r=0.954, pfatty liver with the MRI methods ranged 75–93% for 2PI and 79–89% for 3PI. Our study demonstrates that the apparent HFF measured by the MRI methods can significantly vary depending on the choice of water-fat separation methods and sequences. Such variability may limit the clinical application of the MRI methods, particularly when a diagnosis of early fatty liver needs to be performed. Therefore, protocol-specific establishment of cutoffs for liver fat content may be necessary. PMID:18306404

Characterizing fixed points

Directory of Open Access Journals (Sweden)

Sanjo Zlobec

2017-04-01

Full Text Available A set of sufficient conditions which guarantee the existence of a point x⋆ such that f(x⋆ = x⋆ is called a "fixed point theorem". Many such theorems are named after well-known mathematicians and economists. Fixed point theorems are among most useful ones in applied mathematics, especially in economics and game theory. Particularly important theorem in these areas is Kakutani's fixed point theorem which ensures existence of fixed point for point-to-set mappings, e.g., [2, 3, 4]. John Nash developed and applied Kakutani's ideas to prove the existence of (what became known as "Nash equilibrium" for finite games with mixed strategies for any number of players. This work earned him a Nobel Prize in Economics that he shared with two mathematicians. Nash's life was dramatized in the movie "Beautiful Mind" in 2001. In this paper, we approach the system f(x = x differently. Instead of studying existence of its solutions our objective is to determine conditions which are both necessary and sufficient that an arbitrary point x⋆ is a fixed point, i.e., that it satisfies f(x⋆ = x⋆. The existence of solutions for continuous function f of the single variable is easy to establish using the Intermediate Value Theorem of Calculus. However, characterizing fixed points x⋆, i.e., providing answers to the question of finding both necessary and sufficient conditions for an arbitrary given x⋆ to satisfy f(x⋆ = x⋆, is not simple even for functions of the single variable. It is possible that constructive answers do not exist. Our objective is to find them. Our work may require some less familiar tools. One of these might be the "quadratic envelope characterization of zero-derivative point" recalled in the next section. The results are taken from the author's current research project "Studying the Essence of Fixed Points". They are believed to be original. The author has received several feedbacks on the preliminary report and on parts of the project

Chaos analysis of the electrical signal time series evoked by acupuncture

Energy Technology Data Exchange (ETDEWEB)

Wang Jiang [School of Electrical Engineering, Tianjin University, Tianjin 300072 (China)]. E-mail: jiangwang@tju.edu.cn; Sun Li [School of Electrical Engineering, Tianjin University, Tianjin 300072 (China); Fei Xiangyang [School of Electrical Engineering, Tianjin University, Tianjin 300072 (China); Zhu Bing [Institute of Acupuncture and Moxibustion, China Academy of Traditional Chinese Medicine, Beijing 100700 (China)

2007-08-15

This paper employs chaos theory to analyze the time series of electrical signal which are evoked by different acupuncture methods applied to the Zusanli point. The phase space is reconstructed and the embedding parameters are obtained by the mutual information and Cao's methods. Subsequently, the largest Lyapunov exponent is calculated. From the analyses we can conclude that the time series are chaotic. In addition, differences between various acupuncture methods are discussed.

Comparing Single-Point and Multi-point Calibration Methods in Modulated DSC

Energy Technology Data Exchange (ETDEWEB)

Van Buskirk, Caleb Griffith [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-06-14

Heat capacity measurements for High Density Polyethylene (HDPE) and Ultra-high Molecular Weight Polyethylene (UHMWPE) were performed using Modulated Differential Scanning Calorimetry (mDSC) over a wide temperature range, -70 to 115 °C, with a TA Instruments Q2000 mDSC. The default calibration method for this instrument involves measuring the heat capacity of a sapphire standard at a single temperature near the middle of the temperature range of interest. However, this method often fails for temperature ranges that exceed a 50 °C interval, likely because of drift or non-linearity in the instrument's heat capacity readings over time or over the temperature range. Therefore, in this study a method was developed to calibrate the instrument using multiple temperatures and the same sapphire standard.

An Asynchronous IEEE Floating-Point Arithmetic Unit

Directory of Open Access Journals (Sweden)

Joel R. Noche

2007-12-01

Full Text Available An asynchronous floating-point arithmetic unit is designed and tested at the transistor level usingCadence software. It uses CMOS (complementary metal oxide semiconductor and DCVS (differentialcascode voltage switch logic in a 0.35 µm process using a 3.3 V supply voltage, with dual-rail data andsingle-rail control signals using four-phase handshaking.Using 17,085 transistors, the unit handles single-precision (32-bit addition/subtraction, multiplication,division, and remainder using the IEEE 754-1985 Standard for Binary Floating-Point Arithmetic, withrounding and other operations to be handled by separate hardware or software. Division and remainderare done using a restoring subtractive algorithm; multiplication uses an additive algorithm. Exceptionsare noted by flags (and not trap handlers and the output is in single-precision.Previous work on asynchronous floating-point arithmetic units have mostly focused on single operationssuch as division. This is the first work to the authors' knowledge that can perform floating-point addition,multiplication, division, and remainder using a common datapath.

Estimating Uncertainty of Point-Cloud Based Single-Tree Segmentation with Ensemble Based Filtering

Directory of Open Access Journals (Sweden)

Matthew Parkan

2018-02-01

Full Text Available Individual tree crown segmentation from Airborne Laser Scanning data is a nodal problem in forest remote sensing. Focusing on single layered spruce and fir dominated coniferous forests, this article addresses the problem of directly estimating 3D segment shape uncertainty (i.e., without field/reference surveys, using a probabilistic approach. First, a coarse segmentation (marker controlled watershed is applied. Then, the 3D alpha hull and several descriptors are computed for each segment. Based on these descriptors, the alpha hulls are grouped to form ensembles (i.e., groups of similar tree shapes. By examining how frequently regions of a shape occur within an ensemble, it is possible to assign a shape probability to each point within a segment. The shape probability can subsequently be thresholded to obtain improved (filtered tree segments. Results indicate this approach can be used to produce segmentation reliability maps. A comparison to manually segmented tree crowns also indicates that the approach is able to produce more reliable tree shapes than the initial (unfiltered segmentation.

Optimization of the single point incremental forming process for titanium sheets by using response surface

Directory of Open Access Journals (Sweden)

Saidi Badreddine

2016-01-01

Full Text Available The single point incremental forming process is well-known to be perfectly suited for prototyping and small series. One of its fields of applicability is the medicine area for the forming of titanium prostheses or titanium medical implants. However this process is not yet very industrialized, mainly due its geometrical inaccuracy, its not homogeneous thickness distribution& Moreover considerable forces can occur. They must be controlled in order to preserve the tooling. In this paper, a numerical approach is proposed in order to minimize the maximum force achieved during the incremental forming of titanium sheets and to maximize the minimal thickness. A surface response methodology is used to find the optimal values of two input parameters of the process, the punch diameter and the vertical step size of the tool path.

Proposed method of producing large optical mirrors Single-point diamond crushing followed by polishing with a small-area tool

Science.gov (United States)

Wright, G.; Bryan, J. B.

1986-01-01

Faster production of large optical mirrors may result from combining single-point diamond crushing of the glass with polishing using a small area tool to smooth the surface and remove the damaged layer. Diamond crushing allows a surface contour accurate to 0.5 microns to be generated, and the small area computer-controlled polishing tool allows the surface roughness to be removed without destroying the initial contour. Final contours with an accuracy of 0.04 microns have been achieved.

The influence of shrinkage-cracking on the drying behaviour of White Portland cement using Single-Point Imaging (SPI).

Science.gov (United States)

Beyea, S D; Balcom, B J; Bremner, T W; Prado, P J; Cross, A R; Armstrong, R L; Grattan-Bellew, P E

1998-11-01

The removal of water from pores in hardened cement paste smaller than 50 nm results in cracking of the cement matrix due to the tensile stresses induced by drying shrinkage. Cracks in the matrix fundamentally alter the permeability of the material, and therefore directly affect the drying behaviour. Using Single-Point Imaging (SPI), we obtain one-dimensional moisture profiles of hydrated White Portland cement cylinders as a function of drying time. The drying behaviour of White Portland cement, is distinctly different from the drying behaviour of related concrete materials containing aggregates.

Mitigation of Critical Single Point Failure (SPF) Material - Laminac 4116 Binder Replacement Program for Parachute and Cluster Stars Illuminant Compositions for Hand Held Signals

National Research Council Canada - National Science Library

Lakshminarayanan, G. R; Chen, Gary; Ames, Richard; Lee, Wai T; Wejsa, James L

2006-01-01

Laminac 4116 binder has been identified as a single point failure (SPF) material since it is being produced by only one company and there is a possibility that the company may discontinue production due to low product demand...

A naturally large four-point function in single field inflation

International Nuclear Information System (INIS)

Senatore, Leonardo; Zaldarriaga, Matias

2011-01-01

Non-Gaussianities of the primordial density perturbations have emerged as a very powerful possible signal to test the dynamics that drove the period of inflation. While in general the most sensitive observable is the three-point function in this paper we show that there are technically natural inflationary models where the leading source of non-Gaussianity is the four-point function. Using the recently developed Effective Field Theory of Inflation, we are able to show that it is possible to impose an approximate parity symmetry and an approximate continuos shift symmetry on the inflaton fluctuations that allow, when the dispersion relation if of the form ω ∼ c s k, for a unique quartic operator, while approximately forbidding all the cubic ones. The resulting shape for the four-point function is unique. In the models where the dispersion relation is of the form ω ∼ k 2 /M a similar construction can be carried out and additional shapes are possible

A national assessment of underground natural gas storage: identifying wells with designs likely vulnerable to a single-point-of-failure

Science.gov (United States)

Michanowicz, Drew R.; Buonocore, Jonathan J.; Rowland, Sebastian T.; Konschnik, Katherine E.; Goho, Shaun A.; Bernstein, Aaron S.

2017-05-01

The leak of processed natural gas (PNG) from October 2015 to February 2016 from the Aliso Canyon storage facility, near Los Angeles, California, was the largest single accidental release of greenhouse gases in US history. The Interagency Task Force on Natural Gas Storage Safety and California regulators recently recommended operators phase out single-point-of-failure (SPF) well designs. Here, we develop a national dataset of UGS well activity in the continental US to assess regulatory data availability and uncertainty, and to assess the prevalence of certain well design deficiencies including single-point-of-failure designs. We identified 14 138 active UGS wells associated with 317 active UGS facilities in 29 states using regulatory and company data. State-level wellbore datasets contained numerous reporting inconsistencies that limited data concatenation. We identified 2715 active UGS wells across 160 facilities that, like the failed well at Aliso Canyon, predated the storage facility, and therefore were not originally designed for gas storage. The majority (88%) of these repurposed wells are located in OH, MI, PA, NY, and WV. Repurposed wells have a median age of 74 years, and the 2694 repurposed wells constructed prior to 1979 are particularly likely to exhibit design-related deficiencies. An estimated 210 active repurposed wells were constructed before 1917—before cement zonal isolation methods were utilized. These wells are located in OH, PA, NY, and WV and represent the highest priority related to potential design deficiencies that could lead to containment loss. This national baseline assessment identifies regulatory data uncertainties, highlights a potentially widespread vulnerability of the natural gas supply chain, and can aid in prioritization and oversight for high-risk wells and facilities.

Theoretical and experimental study on active sound transmission control based on single structural mode actuation using point force actuators.

Science.gov (United States)

Sanada, Akira; Tanaka, Nobuo

2012-08-01

This study deals with the feedforward active control of sound transmission through a simply supported rectangular panel using vibration actuators. The control effect largely depends on the excitation method, including the number and locations of actuators. In order to obtain a large control effect at low frequencies over a wide frequency, an active transmission control method based on single structural mode actuation is proposed. Then, with the goal of examining the feasibility of the proposed method, the (1, 3) mode is selected as the target mode and a modal actuation method in combination with six point force actuators is considered. Assuming that a single input single output feedforward control is used, sound transmission in the case minimizing the transmitted sound power is calculated for some actuation methods. Simulation results showed that the (1, 3) modal actuation is globally effective at reducing the sound transmission by more than 10 dB in the low-frequency range for both normal and oblique incidences. Finally, experimental results also showed that a large reduction could be achieved in the low-frequency range, which proves the validity and feasibility of the proposed method.

Quantum Triple Point and Quantum Critical End Points in Metallic Magnets.

Science.gov (United States)

Belitz, D; Kirkpatrick, T R

2017-12-29

In low-temperature metallic magnets, ferromagnetic (FM) and antiferromagnetic (AFM) orders can exist, adjacent to one another or concurrently, in the phase diagram of a single system. We show that universal quantum effects qualitatively alter the known phase diagrams for classical magnets. They shrink the region of concurrent FM and AFM order, change various transitions from second to first order, and, in the presence of a magnetic field, lead to either a quantum triple point where the FM, AFM, and paramagnetic phases all coexist or a quantum critical end point.

A Starting Point for Fluorescence-Based Single-Molecule Measurements in Biomolecular Research

Directory of Open Access Journals (Sweden)

Alexander Gust

2014-09-01

Full Text Available Single-molecule fluorescence techniques are ideally suited to provide information about the structure-function-dynamics relationship of a biomolecule as static and dynamic heterogeneity can be easily detected. However, what type of single-molecule fluorescence technique is suited for which kind of biological question and what are the obstacles on the way to a successful single-molecule microscopy experiment? In this review, we provide practical insights into fluorescence-based single-molecule experiments aiming for scientists who wish to take their experiments to the single-molecule level. We especially focus on fluorescence resonance energy transfer (FRET experiments as these are a widely employed tool for the investigation of biomolecular mechanisms. We will guide the reader through the most critical steps that determine the success and quality of diffusion-based confocal and immobilization-based total internal reflection fluorescence microscopy. We discuss the specific chemical and photophysical requirements that make fluorescent dyes suitable for single-molecule fluorescence experiments. Most importantly, we review recently emerged photoprotection systems as well as passivation and immobilization strategies that enable the observation of fluorescently labeled molecules under biocompatible conditions. Moreover, we discuss how the optical single-molecule toolkit has been extended in recent years to capture the physiological complexity of a cell making it even more relevant for biological research.

Analysis of residual stress state in sheet metal parts processed by single point incremental forming

Science.gov (United States)

Maaß, F.; Gies, S.; Dobecki, M.; Brömmelhoff, K.; Tekkaya, A. E.; Reimers, W.

2018-05-01

The mechanical properties of formed metal components are highly affected by the prevailing residual stress state. A selective induction of residual compressive stresses in the component, can improve the product properties such as the fatigue strength. By means of single point incremental forming (SPIF), the residual stress state can be influenced by adjusting the process parameters during the manufacturing process. To achieve a fundamental understanding of the residual stress formation caused by the SPIF process, a valid numerical process model is essential. Within the scope of this paper the significance of kinematic hardening effects on the determined residual stress state is presented based on numerical simulations. The effect of the unclamping step after the manufacturing process is also analyzed. An average deviation of the residual stress amplitudes in the clamped and unclamped condition of 18 % reveals, that the unclamping step needs to be considered to reach a high numerical prediction quality.

Forty cases of gastrointestinal neurosis treated by acupunture.

Science.gov (United States)

Zhao, Yaping; Ding, Min; Wang, Yanjun

2008-03-01

To compare the therapeutic effect of acupuncture for gastrointestinal neurosis with that of oral remedy. Eighty cases were randomly divided into the following 2 groups. In the treatment group, acupuncture was given for one month at the main points of Zhongwan (CV 12), Zusanli (ST 36), Taichong (LR 3) and Shenmen (HT 7), with the auxiliary points selected according to TCM differentiation. In the control group, Domperidone was orally administered for one month. The total effective rate was 92.5% in the treatment group and 75.0% in the control group, with a significant difference between the 2 groups (chi2 = 4.423, P neurosis and with less toxic side effects.

Point-contact spectroscopic studies on normal and superconducting AFe2As2-type iron pnictide single crystals

International Nuclear Information System (INIS)

Lu Xin; Park, W K; Greene, L H; Yuan, H Q; Chen, G F; Luo, G L; Wang, N L; Sefat, A S; McGuire, M A; Jin, R; Sales, B C; Mandrus, D; Gillett, J; Sebastian, Suchitra E

2010-01-01

Point-contact Andreev reflection spectroscopy is applied to investigate the gap structure in iron pnictide single-crystal superconductors of the AFe 2 As 2 (A = Ba, Sr) family ('Fe-122'). The observed point-contact junction conductance curves, G(V), can be divided into two categories: one where Andreev reflection is present for both (Ba 0.6 K 0.4 )Fe 2 As 2 and Ba(Fe 0.9 Co 0.1 ) 2 As 2 , and the other with a V 2/3 background conductance universally observed, extending even up to 100 meV for Sr 0.6 Na 0.4 Fe 2 As 2 and Sr(Fe 0.9 Co 0.1 ) 2 As 2 . The latter is also observed in point-contact junctions on the nonsuperconducting parent compound BaFe 2 As 2 and superconducting (Ba 0.6 K 0.4 )Fe 2 As 2 crystals. Mesoscopic phase-separated coexistence of magnetic and superconducting orders is considered to explain distinct behaviors in the superconducting samples. For Ba 0.6 K 0.4 Fe 2 As 2 , double peaks due to Andreev reflection with a strongly sloping background are frequently observed for point contacts on freshly cleaved c-axis surfaces. If normalized using a background baseline and analyzed using the Blonder-Tinkham-Klapwijk model, the data show a gap size of ∼ 3.0-4.0 meV with 2Δ 0 /k B T c ∼ 2.0-2.6, consistent with the smaller gap size reported for the LnFeAsO family ('Fe-1111'). For the Ba(Fe 0.9 Co 0.1 ) 2 As 2 , the G(V) curves typically display a zero-bias conductance peak.

Noncontact on-machine measurement system based on capacitive displacement sensors for single-point diamond turning

Science.gov (United States)

Li, Xingchang; Zhang, Zhiyu; Hu, Haifei; Li, Yingjie; Xiong, Ling; Zhang, Xuejun; Yan, Jiwang

2018-04-01

On-machine measurements can improve the form accuracy of optical surfaces in single-point diamond turning applications; however, commercially available linear variable differential transformer sensors are inaccurate and can potentially scratch the surface. We present an on-machine measurement system based on capacitive displacement sensors for high-precision optical surfaces. In the proposed system, a position-trigger method of measurement was developed to ensure strict correspondence between the measurement points and the measurement data with no intervening time-delay. In addition, a double-sensor measurement was proposed to reduce the electric signal noise during spindle rotation. Using the proposed system, the repeatability of 80-nm peak-to-valley (PV) and 8-nm root-mean-square (RMS) was achieved through analyzing four successive measurement results. The accuracy of 109-nm PV and 14-nm RMS was obtained by comparing with the interferometer measurement result. An aluminum spherical mirror with a diameter of 300 mm was fabricated, and the resulting measured form error after one compensation cut was decreased to 254 nm in PV and 52 nm in RMS. These results confirm that the measurements of the surface form errors were successfully used to modify the cutting tool path during the compensation cut, thereby ensuring that the diamond turning process was more deterministic. In addition, the results show that the noise level was significantly reduced with the reference sensor even under a high rotational speed.

Quantifying He-point defect interactions in Fe through coordinated experimental and modeling studies of He-ion implanted single-crystal Fe

Energy Technology Data Exchange (ETDEWEB)

Hu, Xunxiang, E-mail: xunxianghu@berkeley.edu [Department of Nuclear Engineering, University of California, Berkeley, CA 94720-1730 (United States); Xu, Donghua; Wirth, Brian D. [Department of Nuclear Engineering, University of California, Berkeley, CA 94720-1730 (United States); Department of Nuclear Engineering, University of Tennessee, Knoxville, TN 37996-2300 (United States)

2013-11-15

Understanding the effects of helium on the microstructural evolution and mechanical properties of structural materials are among the most challenging issues in fusion materials research. In this work, we combine thermal helium desorption spectroscopy (THDS) with positron annihilation spectroscopy (PAS) and a spatially dependent cluster dynamics model to investigate the energetics of helium-point defect interactions in helium-implanted single-crystal iron. The combination of modeling and thermal desorption measurements allows identification of the binding energies of small He–V clusters, the migration energy of single vacancy and possible mechanisms (e.g., shrinkage of He{sub 3}V{sub 2} clusters) responsible for measured Helium desorption peaks, and the effect of impurities (e.g., carbon) on these values. Furthermore, the model predicts the depth dependence of the helium and helium–vacancy clusters as a function of time and temperature during the thermal desorption measurement. Here, we report the THDS measurement results as a function of He implantation energy from 10 to 40 keV at a fluence level of 1 × 10{sup 15} He/cm{sup 2}, along with selected PAS measurements. The experimental results are compared to the modeling predictions to evaluate the extent to which self-consistent values of the He-point defect binding and interaction energies and diffusivities can explain the data.

A precise pointing nanopipette for single-cell imaging via electroosmotic injection.

Science.gov (United States)

Lv, Jian; Qian, Ruo-Can; Hu, Yong-Xu; Liu, Shao-Chuang; Cao, Yue; Zheng, Yong-Jie; Long, Yi-Tao

2016-11-24

The precise transportation of fluorescent probes to the designated location in living cells is still a challenge. Here, we present a new addition to nanopipettes as a powerful tool to deliver fluorescent molecules to a given place in a single cell by electroosmotic flow, indicating favorable potential for further application in single-cell imaging.

Four-point functions in N=4 SYM

International Nuclear Information System (INIS)

Heslop, Paul J.; Howe, Paul S.

2003-01-01

A new derivation is given of four-point functions of charge Q chiral primary multiplets in N=4 supersymmetric Yang-Mills theory. A compact formula, valid for arbitrary Q, is given which is manifestly superconformal and analytic in the internal bosonic coordinates of analytic superspace. This formula allows one to determine the spacetime four-point function of any four component fields in the multiplets in terms of the four-point function of the leading chiral primary fields. The leading term is expressed in terms of 1/2Q(Q-1) functions of two conformal invariants and a number of single variable functions. Crossing symmetry reduces the number of independent functions, while the OPE implies that the single-variable functions arise from protected operators and should therefore take their free form. This is the partial non-renormalisation property of such four-point functions which can be viewed as a consequence of the OPE and the non-renormalisation of three-point functions of protected operators. (author)

Pan European Phenological database (PEP725): a single point of access for European data

Science.gov (United States)

Templ, Barbara; Koch, Elisabeth; Bolmgren, Kjell; Ungersböck, Markus; Paul, Anita; Scheifinger, Helfried; Rutishauser, This; Busto, Montserrat; Chmielewski, Frank-M.; Hájková, Lenka; Hodzić, Sabina; Kaspar, Frank; Pietragalla, Barbara; Romero-Fresneda, Ramiro; Tolvanen, Anne; Vučetič, Višnja; Zimmermann, Kirsten; Zust, Ana

2018-02-01

The Pan European Phenology (PEP) project is a European infrastructure to promote and facilitate phenological research, education, and environmental monitoring. The main objective is to maintain and develop a Pan European Phenological database (PEP725) with an open, unrestricted data access for science and education. PEP725 is the successor of the database developed through the COST action 725 "Establishing a European phenological data platform for climatological applications" working as a single access point for European-wide plant phenological data. So far, 32 European meteorological services and project partners from across Europe have joined and supplied data collected by volunteers from 1868 to the present for the PEP725 database. Most of the partners actively provide data on a regular basis. The database presently holds almost 12 million records, about 46 growing stages and 265 plant species (including cultivars), and can be accessed via http://www.pep725.eu/. Users of the PEP725 database have studied a diversity of topics ranging from climate change impact, plant physiological question, phenological modeling, and remote sensing of vegetation to ecosystem productivity.

Pan European Phenological database (PEP725): a single point of access for European data

Science.gov (United States)

Templ, Barbara; Koch, Elisabeth; Bolmgren, Kjell; Ungersböck, Markus; Paul, Anita; Scheifinger, Helfried; Rutishauser, This; Busto, Montserrat; Chmielewski, Frank-M.; Hájková, Lenka; Hodzić, Sabina; Kaspar, Frank; Pietragalla, Barbara; Romero-Fresneda, Ramiro; Tolvanen, Anne; Vučetič, Višnja; Zimmermann, Kirsten; Zust, Ana

2018-06-01

The Pan European Phenology (PEP) project is a European infrastructure to promote and facilitate phenological research, education, and environmental monitoring. The main objective is to maintain and develop a Pan European Phenological database (PEP725) with an open, unrestricted data access for science and education. PEP725 is the successor of the database developed through the COST action 725 "Establishing a European phenological data platform for climatological applications" working as a single access point for European-wide plant phenological data. So far, 32 European meteorological services and project partners from across Europe have joined and supplied data collected by volunteers from 1868 to the present for the PEP725 database. Most of the partners actively provide data on a regular basis. The database presently holds almost 12 million records, about 46 growing stages and 265 plant species (including cultivars), and can be accessed via http://www.pep725.eu/ . Users of the PEP725 database have studied a diversity of topics ranging from climate change impact, plant physiological question, phenological modeling, and remote sensing of vegetation to ecosystem productivity.

An equilibrium-point model for fast, single-joint movement: I. Emergence of strategy-dependent EMG patterns.

Science.gov (United States)

Latash, M L; Gottlieb, G L

1991-09-01

We describe a model for the regulation of fast, single-joint movements, based on the equilibrium-point hypothesis. Limb movement follows constant rate shifts of independently regulated neuromuscular variables. The independently regulated variables are tentatively identified as thresholds of a length sensitive reflex for each of the participating muscles. We use the model to predict EMG patterns associated with changes in the conditions of movement execution, specifically, changes in movement times, velocities, amplitudes, and moments of limb inertia. The approach provides a theoretical neural framework for the dual-strategy hypothesis, which considers certain movements to be results of one of two basic, speed-sensitive or speed-insensitive strategies. This model is advanced as an alternative to pattern-imposing models based on explicit regulation of timing and amplitudes of signals that are explicitly manifest in the EMG patterns.

Impedance analysis of acupuncture points and pathways

International Nuclear Information System (INIS)

Teplan, Michal; Kukucka, Marek; Ondrejkovicová, Alena

2011-01-01

Investigation of impedance characteristics of acupuncture points from acoustic to radio frequency range is addressed. Discernment and localization of acupuncture points in initial single subject study was unsuccessfully attempted by impedance map technique. Vector impedance analyses determined possible resonant zones in MHz region.

A rapid and robust gradient measurement technique using dynamic single-point imaging.

Science.gov (United States)

Jang, Hyungseok; McMillan, Alan B

2017-09-01

We propose a new gradient measurement technique based on dynamic single-point imaging (SPI), which allows simple, rapid, and robust measurement of k-space trajectory. To enable gradient measurement, we utilize the variable field-of-view (FOV) property of dynamic SPI, which is dependent on gradient shape. First, one-dimensional (1D) dynamic SPI data are acquired from a targeted gradient axis, and then relative FOV scaling factors between 1D images or k-spaces at varying encoding times are found. These relative scaling factors are the relative k-space position that can be used for image reconstruction. The gradient measurement technique also can be used to estimate the gradient impulse response function for reproducible gradient estimation as a linear time invariant system. The proposed measurement technique was used to improve reconstructed image quality in 3D ultrashort echo, 2D spiral, and multi-echo bipolar gradient-echo imaging. In multi-echo bipolar gradient-echo imaging, measurement of the k-space trajectory allowed the use of a ramp-sampled trajectory for improved acquisition speed (approximately 30%) and more accurate quantitative fat and water separation in a phantom. The proposed dynamic SPI-based method allows fast k-space trajectory measurement with a simple implementation and no additional hardware for improved image quality. Magn Reson Med 78:950-962, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

Obtaining Global Picture From Single Point Observations by Combining Data Assimilation and Machine Learning Tools

Science.gov (United States)

Shprits, Y.; Zhelavskaya, I. S.; Kellerman, A. C.; Spasojevic, M.; Kondrashov, D. A.; Ghil, M.; Aseev, N.; Castillo Tibocha, A. M.; Cervantes Villa, J. S.; Kletzing, C.; Kurth, W. S.

2017-12-01

Increasing volume of satellite measurements requires deployment of new tools that can utilize such vast amount of data. Satellite measurements are usually limited to a single location in space, which complicates the data analysis geared towards reproducing the global state of the space environment. In this study we show how measurements can be combined by means of data assimilation and how machine learning can help analyze large amounts of data and can help develop global models that are trained on single point measurement. Data Assimilation: Manual analysis of the satellite measurements is a challenging task, while automated analysis is complicated by the fact that measurements are given at various locations in space, have different instrumental errors, and often vary by orders of magnitude. We show results of the long term reanalysis of radiation belt measurements along with fully operational real-time predictions using data assimilative VERB code. Machine Learning: We present application of the machine learning tools for the analysis of NASA Van Allen Probes upper-hybrid frequency measurements. Using the obtained data set we train a new global predictive neural network. The results for the Van Allen Probes based neural network are compared with historical IMAGE satellite observations. We also show examples of predictions of geomagnetic indices using neural networks. Combination of machine learning and data assimilation: We discuss how data assimilation tools and machine learning tools can be combine so that physics-based insight into the dynamics of the particular system can be combined with empirical knowledge of it's non-linear behavior.

Active point out-of-plane ultrasound calibration

Science.gov (United States)

Cheng, Alexis; Guo, Xiaoyu; Zhang, Haichong K.; Kang, Hyunjae; Etienne-Cummings, Ralph; Boctor, Emad M.

2015-03-01

Image-guided surgery systems are often used to provide surgeons with informational support. Due to several unique advantages such as ease of use, real-time image acquisition, and no ionizing radiation, ultrasound is a common intraoperative medical imaging modality used in image-guided surgery systems. To perform advanced forms of guidance with ultrasound, such as virtual image overlays or automated robotic actuation, an ultrasound calibration process must be performed. This process recovers the rigid body transformation between a tracked marker attached to the transducer and the ultrasound image. Point-based phantoms are considered to be accurate, but their calibration framework assumes that the point is in the image plane. In this work, we present the use of an active point phantom and a calibration framework that accounts for the elevational uncertainty of the point. Given the lateral and axial position of the point in the ultrasound image, we approximate a circle in the axial-elevational plane with a radius equal to the axial position. The standard approach transforms all of the imaged points to be a single physical point. In our approach, we minimize the distances between the circular subsets of each image, with them ideally intersecting at a single point. We simulated in noiseless and noisy cases, presenting results on out-of-plane estimation errors, calibration estimation errors, and point reconstruction precision. We also performed an experiment using a robot arm as the tracker, resulting in a point reconstruction precision of 0.64mm.

A single point acupuncture treatment at large intestine meridian: a randomized controlled trial in acute tonsillitis and pharyngitis.

Science.gov (United States)

Fleckenstein, Johannes; Lill, Christian; Lüdtke, Rainer; Gleditsch, Jochen; Rasp, Gerd; Irnich, Dominik

2009-09-01

One out of 4 patients visiting a general practitioner reports of a sore throat associated with pain on swallowing. This study was established to examine the immediate pain alleviating effect of a single point acupuncture treatment applied to the large intestine meridian of patients with sore throat. Sixty patients with acute tonsillitis and pharyngitis were enrolled in this randomized placebo-controlled trial. They either received acupuncture, or sham laser acupuncture, directed to the large intestine meridian section between acupuncture points LI 8 and LI 10. The main outcome measure was the change of pain intensity on swallowing a sip of water evaluated by a visual analog scale 15 minutes after treatment. A credibility assessment regarding the respective treatment was performed. The pain intensity for the acupuncture group before and immediately after therapy was 5.6+/-2.8 and 3.0+/-3.0, and for the sham group 5.6+/-2.5 and 3.8+/-2.5, respectively. Despite the articulation of a more pronounced improvement among the acupuncture group, there was no significant difference between groups (Delta=0.9, confidence interval: -0.2-2.0; P=0.12; analysis of covariance). Patients' satisfaction was high in both treatment groups. The study was prematurely terminated due to a subsequent lack of suitable patients. A single acupuncture treatment applied to a selected area of the large intestine meridian was no more effective in the alleviation of pain associated with clinical sore throat than sham laser acupuncture applied to the same area. Hence, clinically relevant improvement could be achieved. Pain alleviation might partly be due to the intense palpation of the large intestine meridian. The benefit of a comprehensive acupuncture treatment protocol in this condition should be subject to further trials.

Statistical representation of a spray as a point process

International Nuclear Information System (INIS)

Subramaniam, S.

2000-01-01

The statistical representation of a spray as a finite point process is investigated. One objective is to develop a better understanding of how single-point statistical information contained in descriptions such as the droplet distribution function (ddf), relates to the probability density functions (pdfs) associated with the droplets themselves. Single-point statistical information contained in the droplet distribution function (ddf) is shown to be related to a sequence of single surrogate-droplet pdfs, which are in general different from the physical single-droplet pdfs. It is shown that the ddf contains less information than the fundamental single-point statistical representation of the spray, which is also described. The analysis shows which events associated with the ensemble of spray droplets can be characterized by the ddf, and which cannot. The implications of these findings for the ddf approach to spray modeling are discussed. The results of this study also have important consequences for the initialization and evolution of direct numerical simulations (DNS) of multiphase flows, which are usually initialized on the basis of single-point statistics such as the droplet number density in physical space. If multiphase DNS are initialized in this way, this implies that even the initial representation contains certain implicit assumptions concerning the complete ensemble of realizations, which are invalid for general multiphase flows. Also the evolution of a DNS initialized in this manner is shown to be valid only if an as yet unproven commutation hypothesis holds true. Therefore, it is questionable to what extent DNS that are initialized in this manner constitute a direct simulation of the physical droplets. Implications of these findings for large eddy simulations of multiphase flows are also discussed. (c) 2000 American Institute of Physics

Space nuclear reactor concepts for avoidance of a single point failure

International Nuclear Information System (INIS)

El-Genk, M. S.

2007-01-01

This paper presents three space nuclear reactor concepts for future exploration missions requiring electrical power of 10's to 100's kW, for 7-10 years. These concepts avoid a single point failure in reactor cooling; and they could be used with a host of energy conversion technologies. The first is lithium or sodium heat pipes cooled reactor. The heat pipes operate at a fraction of their prevailing capillary or sonic limit. Thus, when a number of heat pipes fail, those in the adjacent modules remove their heat load, maintaining reactor core adequately cooled. The second is a reactor with a circulating liquid metal coolant. The reactor core is divided into six identical sectors, each with a separate energy conversion loop. The sectors in the reactor core are neurotically coupled, but hydraulically decoupled. Thus, when a sector experiences a loss of coolant, the fission power generated in it will be removed by the circulating coolant in the adjacent sectors. In this case, however, the reactor fission power would have to decrease to avoid exceeding the design temperature limits in the sector with a failed loop. These two reactor concepts are used with energy conversion technologies, such as advanced Thermoelectric (TE), Free Piston Stirling Engines (FPSE), and Alkali Metal Thermal-to- Electric Conversion (AMTEC). Gas cooled reactors are a better choice to use with Closed Brayton Cycle engines, such as the third reactor concept to be presented in the paper. It has a sectored core that is cooled with a binary mixture of He-Xe (40 gm/mole). Each of the three sectors in the reactor has its own CBC and neutronically, but not hydraulically, coupled to the other sectors

Long-Term and Short-Term Effects of Hemodialysis on Liver Function Evaluated Using the Galactose Single-Point Test

Directory of Open Access Journals (Sweden)

Yi-Chou Hou

2014-01-01

Full Text Available Aim. The galactose single-point (GSP test assesses functioning liver mass by measuring the galactose concentration in the blood 1 hour after its administration. The purpose of this study was to investigate the impact of hemodialysis (HD on short-term and long-term liver function by use of GSP test. Methods. Seventy-four patients on maintenance HD (46 males and 28 females, 60.38 ± 11.86 years with a mean time on HD of 60.77 ± 48.31 months were studied. The GSP values were compared in two groups: (1 before and after single session HD, and (2 after one year of maintenance HD. Results. Among the 74 HD patient, only the post-HD Cr levels and years on dialysis were significantly correlated with GSP values (r=0.280, P<0.05 and r=-0.240, P<0.05, resp.. 14 of 74 patients were selected for GSP evaluation before and after a single HD session, and the hepatic clearance of galactose was similar (pre-HD 410 ± 254 g/mL, post-HD 439 ± 298 g/mL, P=0.49. GSP values decreased from 420.20 ± 175.26 g/mL to 383.40 ± 153.97 g/mL after 1 year maintenance HD in other 15 patients (mean difference: 19.00 ± 37.66 g/mL, P<0.05. Conclusions. Patients on maintenance HD for several years may experience improvement of their liver function. However, a single HD session does not affect liver function significantly as assessed by the GSP test. Since the metabolism of galactose is dependent on liver blood flow and hepatic functional mass, further studies are needed.

Single-Point Incremental Forming of Two Biocompatible Polymers: An Insight into Their Thermal and Structural Properties

Directory of Open Access Journals (Sweden)

Luis Marcelo Lozano-Sánchez

2018-04-01

Full Text Available Sheets of polycaprolactone (PCL and ultra-high molecular weight polyethylene (UHMWPE were fabricated and shaped by the Single-Point Incremental Forming process (SPIF. The performance of these biocompatible polymers in SPIF was assessed through the variation of four main parameters: the diameter of the forming tool, the spindle speed, the feed rate, and the step size based on a Box–Behnken design of experiments of four variables and three levels. The design of experiments allowed us to identify the parameters that most affect the forming of PCL and UHMWPE. The study was completed by means of a deep characterization of the thermal and structural properties of both polymers. These properties were correlated to the performance of the polymers observed in SPIF, and it was found that the polymer chains are oriented as a consequence of the SPIF processing. Moreover, by X-ray diffraction it was proved that polymer chains behave differently on each surface of the fabricated parts, since the chains on the surface in contact with the forming tool are oriented horizontally, while on the opposite surface they are oriented in the vertical direction. The unit cell of UHMWPE is distorted, passing from an orthorhombic cell to a monoclinic due to the slippage between crystallites. This slippage between crystallites was observed in both PCL and UHMWPE, and was identified as an alpha star thermal transition located in the rubbery region between the glass transition and the melting point of each polymer.

Highly efficient maximum power point tracking using DC-DC coupled inductor single-ended primary inductance converter for photovoltaic power systems

Science.gov (United States)

Quamruzzaman, M.; Mohammad, Nur; Matin, M. A.; Alam, M. R.

2016-10-01

Solar photovoltaics (PVs) have nonlinear voltage-current characteristics, with a distinct maximum power point (MPP) depending on factors such as solar irradiance and operating temperature. To extract maximum power from the PV array at any environmental condition, DC-DC converters are usually used as MPP trackers. This paper presents the performance analysis of a coupled inductor single-ended primary inductance converter for maximum power point tracking (MPPT) in a PV system. A detailed model of the system has been designed and developed in MATLAB/Simulink. The performance evaluation has been conducted on the basis of stability, current ripple reduction and efficiency at different operating conditions. Simulation results show considerable ripple reduction in the input and output currents of the converter. Both the MPPT and converter efficiencies are significantly improved. The obtained simulation results validate the effectiveness and suitability of the converter model in MPPT and show reasonable agreement with the theoretical analysis.

Control of anisotropic shape deviation in single point incremental forming of paperboard

Science.gov (United States)

Stein, Philipp; Franke, Wilken; Hoppe, Florian; Hesse, Daniel; Mill, Katharina; Groche, Peter

2017-10-01

The increasing social demand for sustainable material use leads to new process strategies as well as to the use of new materials in nearly all industries. In light of this demand, paperboard shows potential to substitute polymer-based components while also exhibiting improved ecological properties. However, in contrast to polymer-based products, the forming limits of paperboard are relatively low. Therefore, three dimensional forming of paperboard is subject of current research. One area of research focuses on the control of the fiber orientation dependent anisotropic material behavior of industrial paperboard in forming processes. For an examined industrial paperboard, an average elongation at break of 1.2% in the so called machine direction (fiber preferential direction, MD) has been determined at standard climate conditions. In contrast, in cross-direction (orthogonal to the machine direction, CD) a value of 2.6% was observed. With increased moisture content of the specimens the difference between the mechanical properties in MD and CD even increases. As a result of the various fiber-orientation dependent mechanical properties, forming with symmetric tools leads to asymmetrically shaped final parts. Within this article, an approach to reduce the asymmetric shape of three-dimensional formed paperboard by using single point incremental forming technology is presented. For a free spatial processing strategy the 3D Servo Press Technology, which enables circular as well as free processing strategies, is used. Based on reference tests with a circular processing strategy, it is shown that by using an adapted, elliptical tool path, an almost symmetric shaped part can be formed.

Apollo: giving application developers a single point of access to public health models using structured vocabularies and Web services.

Science.gov (United States)

Wagner, Michael M; Levander, John D; Brown, Shawn; Hogan, William R; Millett, Nicholas; Hanna, Josh

2013-01-01

This paper describes the Apollo Web Services and Apollo-SV, its related ontology. The Apollo Web Services give an end-user application a single point of access to multiple epidemic simulators. An end user can specify an analytic problem-which we define as a configuration and a query of results-exactly once and submit it to multiple epidemic simulators. The end user represents the analytic problem using a standard syntax and vocabulary, not the native languages of the simulators. We have demonstrated the feasibility of this design by implementing a set of Apollo services that provide access to two epidemic simulators and two visualizer services.

Single Cell Assay for Analyzing Single Cell Exosome and Endocrine Secretion and Cancer Markers

Science.gov (United States)

Chiu, Yu-Jui

To understand the inhomogeneity of cells in biological systems, there is a growing demand for the capability to characterize the properties of individual single cells. Since single cell studies require continuous monitoring of the cell behaviors instead of a snapshot test at a single time point, an effective single-cell assay that can support time lapsed studies in a high throughput manner is desired. Most currently available single-cell technologies cannot provide proper environments to sustain cell growth and cannot provide, for appropriate cell types, proliferation of single cells and convenient, non-invasive tests of single cell behaviors from molecular markers. In this dissertation, I present a highly versatile single-cell assay that can accommodate different cellular types, enable easy and efficient single cell loading and culturing, and be suitable for the study of effects of in-vitro environmental factors in combination with drug screening. The salient features of the assay are the non-invasive collection and surveying of single cell secretions at different time points and massively parallel translocation of single cells by user defined criteria, producing very high compatibility to the downstream process such as single cell qPCR and sequencing. Above all, the acquired information is quantitative -- for example, one of the studies is measured by the number of exosomes each single cell secretes for a given time period. Therefore, our single-cell assay provides a convenient, low-cost, and enabling tool for quantitative, time lapsed studies of single cell properties.

Single point estimation of phenytoin dosing: a reappraisal.

Science.gov (United States)

Koup, J R; Gibaldi, M; Godolphin, W

1981-11-01

A previously proposed method for estimation of phenytoin dosing requirement using a single serum sample obtained 24 hours after intravenous loading dose (18 mg/Kg) has been re-evaluated. Using more realistic values for the volume of distribution of phenytoin (0.4 to 1.2 L/Kg), simulations indicate that the proposed method will fail to consistently predict dosage requirements. Additional simulations indicate that two samples obtained during the 24 hour interval following the iv loading dose could be used to more reliably predict phenytoin dose requirement. Because of the nonlinear relationship which exists between phenytoin dose administration rate (RO) and the mean steady state serum concentration (CSS), small errors in prediction of the required RO result in much larger errors in CSS.

An SVM-Based Classifier for Estimating the State of Various Rotating Components in Agro-Industrial Machinery with a Vibration Signal Acquired from a Single Point on the Machine Chassis

Directory of Open Access Journals (Sweden)

Ruben Ruiz-Gonzalez

2014-11-01

Full Text Available The goal of this article is to assess the feasibility of estimating the state of various rotating components in agro-industrial machinery by employing just one vibration signal acquired from a single point on the machine chassis. To do so, a Support Vector Machine (SVM-based system is employed. Experimental tests evaluated this system by acquiring vibration data from a single point of an agricultural harvester, while varying several of its working conditions. The whole process included two major steps. Initially, the vibration data were preprocessed through twelve feature extraction algorithms, after which the Exhaustive Search method selected the most suitable features. Secondly, the SVM-based system accuracy was evaluated by using Leave-One-Out cross-validation, with the selected features as the input data. The results of this study provide evidence that (i accurate estimation of the status of various rotating components in agro-industrial machinery is possible by processing the vibration signal acquired from a single point on the machine structure; (ii the vibration signal can be acquired with a uniaxial accelerometer, the orientation of which does not significantly affect the classification accuracy; and, (iii when using an SVM classifier, an 85% mean cross-validation accuracy can be reached, which only requires a maximum of seven features as its input, and no significant improvements are noted between the use of either nonlinear or linear kernels.

Single-photon compressive imaging with some performance benefits over raster scanning

International Nuclear Information System (INIS)

Yu, Wen-Kai; Liu, Xue-Feng; Yao, Xu-Ri; Wang, Chao; Zhai, Guang-Jie; Zhao, Qing

2014-01-01

A single-photon imaging system based on compressed sensing has been developed to image objects under ultra-low illumination. With this system, we have successfully realized imaging at the single-photon level with a single-pixel avalanche photodiode without point-by-point raster scanning. From analysis of the signal-to-noise ratio in the measurement we find that our system has much higher sensitivity than conventional ones based on point-by-point raster scanning, while the measurement time is also reduced. - Highlights: • We design a single photon imaging system with compressed sensing. • A single point avalanche photodiode is used without raster scanning. • The Poisson shot noise in the measurement is analyzed. • The sensitivity of our system is proved to be higher than that of raster scanning

[Effect of electroacupuncture on the expression of oligodendrocyte precursor cells in rats with compressed spinal cord injury].

Science.gov (United States)

Huang, Si-qin; Qi, Wei; Zeng, Zhi-hua; Wang, Ke-jian; Wu, Xiu-yu

2014-11-01

To investigate the effect of electroacupuncture on the expression of oligodendrocyte precursor cells in rats with compressed spinal cord injury (CSCI) and to explore the mechanism of remyelinization. Thirty-six SD rats were randomly divided into a control group and three treatment groups with 3 d, 7 d and 14 d of treatment respectively. Acupuncture was given to rats in the treatment groups through jiaji point, double zusanli (ST36), and double taixi (KI3). Electroacupuncture (continuous wave, 2 Hz/1. 5 V, 30 min) was applied for the double zusanli (ST36) and double taixi (KI3). Ethological alterations of the rats were observed with quantitative assessment of neurologic function. The ultrastructure changes of nerve fibers in white matter were determined under electronic microscope. Expressions of NG2 protein, an OPC marker, was observed by Western blot. No significant changes in neurologic function and G-ratio were observed after three days and seven days of electroacupuncture treatment (P>0. 05). However, 14 d of electroacupuncture treatment made a significant change compared to the 7 d treatment group and the control group (PElectroacupuncture can improve inflammation and edema in the injured nerve fibers and up regulate NG2 expression and remyelination of the injured nerve fibers in rats with CSCI.

Two gap superconductivity in Ba0.55K0.45Fe2As2 single crystals studied by the directional point-contact Andreev reflection spectroscopy

International Nuclear Information System (INIS)

Szabo, P.; Pribulova, Z.; Pristas, G.; Bud'ko, S.L.; Canfield, P.C.; Samuely, P.

2009-01-01

First directional point-contact Andreev reflection spectroscopy on the Ba 0.55 K 0.45 Fe 2 As 2 single crystals is presented. The spectra show significant differences when measured in the ab plane in comparison with those measured in the c direction. In the latter case no traces of superconducting energy gap could be found, just a reduced point-contact conductance persisting up to about 100 K and indicating reduced density of states. On the other hand within the ab plane two nodeless superconducting energy gaps Δ S ∼2-5 meV and Δ L ∼9-11 meV are detected.

Forces, surface finish and friction characteristics in surface engineered single- and multiple-point cutting edges

International Nuclear Information System (INIS)

Sarwar, M.; Gillibrand, D.; Bradbury, S.R.

1991-01-01

Advanced surface engineering technologies (physical and chemical vapour deposition) have been successfully applied to high speed steel and carbide cutting tools, and the potential benefits in terms of both performance and longer tool life, are now well established. Although major achievements have been reported by many manufacturers and users, there are a number of applications where surface engineering has been unsuccessful. Considerable attention has been given to the film characteristics and the variables associated with its properties; however, very little attention has been directed towards the benefits to the tool user. In order to apply surface engineering technology effectively to cutting tools, the coater needs to have accurate information relating to cutting conditions, i.e. cutting forces, stress and temperature etc. The present paper describes results obtained with single- and multiple-point cutting tools with examples of failures, which should help the surface coater to appreciate the significance of the cutting conditions, and in particular the magnitude of the forces and stresses present during cutting processes. These results will assist the development of a systems approach to cutting tool technology and surface engineering with a view to developing an improved product. (orig.)

Exceptional points enhance sensing in an optical microcavity

Science.gov (United States)

Chen, Weijian; Kaya Özdemir, Şahin; Zhao, Guangming; Wiersig, Jan; Yang, Lan

2017-08-01

Sensors play an important part in many aspects of daily life such as infrared sensors in home security systems, particle sensors for environmental monitoring and motion sensors in mobile phones. High-quality optical microcavities are prime candidates for sensing applications because of their ability to enhance light-matter interactions in a very confined volume. Examples of such devices include mechanical transducers, magnetometers, single-particle absorption spectrometers, and microcavity sensors for sizing single particles and detecting nanometre-scale objects such as single nanoparticles and atomic ions. Traditionally, a very small perturbation near an optical microcavity introduces either a change in the linewidth or a frequency shift or splitting of a resonance that is proportional to the strength of the perturbation. Here we demonstrate an alternative sensing scheme, by which the sensitivity of microcavities can be enhanced when operated at non-Hermitian spectral degeneracies known as exceptional points. In our experiments, we use two nanoscale scatterers to tune a whispering-gallery-mode micro-toroid cavity, in which light propagates along a concave surface by continuous total internal reflection, in a precise and controlled manner to exceptional points. A target nanoscale object that subsequently enters the evanescent field of the cavity perturbs the system from its exceptional point, leading to frequency splitting. Owing to the complex-square-root topology near an exceptional point, this frequency splitting scales as the square root of the perturbation strength and is therefore larger (for sufficiently small perturbations) than the splitting observed in traditional non-exceptional-point sensing schemes. Our demonstration of exceptional-point-enhanced sensitivity paves the way for sensors with unprecedented sensitivity.

Limited Sampling Strategy for the Prediction of Area Under the Curve (AUC) of Statins: Reliability of a Single Time Point for AUC Prediction for Pravastatin and Simvastatin.

Science.gov (United States)

Srinivas, N R

2016-02-01

Statins are widely prescribed medicines and are also available in fixed dose combinations with other drugs to treat several chronic ailments. Given the safety issues associated with statins it may be important to assess feasibility of a single time concentration strategy for prediction of exposure (area under the curve; AUC). The peak concentration (Cmax) was used to establish relationship with AUC separately for pravastatin and simvastatin using published pharmacokinetic data. The regression equations generated for statins were used to predict the AUC values from various literature references. The fold difference of the observed divided by predicted values along with correlation coefficient (r) were used to judge the feasibility of the single time point approach. Both pravastatin and simvastatin showed excellent correlation of Cmax vs. AUC values with r value ≥ 0.9638 (pAUC predictions and >81% of the predicted values were in a narrower range of >0.75-fold but AUC values showed excellent correlation for pravastatin (r=0.9708, n=115; pAUC predictions. On the basis of the present work, it is feasible to develop a single concentration time point strategy that coincides with Cmax occurrence for both pravastatin and simvastatin from a therapeutic drug monitoring perspective. © Georg Thieme Verlag KG Stuttgart · New York.

Hybrid fixed point in CAT(0 spaces

Directory of Open Access Journals (Sweden)

Hemant Kumar Pathak

2018-02-01

Full Text Available In this paper, we introduce an ultrapower approach to prove fixed point theorems for $H^{+}$-nonexpansive multi-valued mappings in the setting of CAT(0 spaces and prove several hybrid fixed point results in CAT(0 spaces for families of single-valued nonexpansive or quasinonexpansive mappings and multi-valued upper semicontinuous, almost lower semicontinuous or $H^{+}$-nonexpansive mappings which are weakly commuting. We also establish a result about structure of the set of fixed points of $H^{+}$-quasinonexpansive mapping on a CAT(0 space.

The use of single point incremental forming for customized implants of unicondylar knee arthroplasty: a review

Directory of Open Access Journals (Sweden)

Pankaj Kailasrao Bhoyar

Full Text Available Abstract Introduction The implantable devices are having enormous market. These products are basically made by traditional manufacturing process, but for the custom-made implants Incremental Sheet Forming is a paramount alternative. Single Point Incremental Forming (SPIF is a manufacturing process to form intricate, asymmetrical components. It forms the component using stretching and bending by maintaining materials crystal structure. SPIF process can be performed using conventional Computer Numerical Control (CNC milling machine. Review This review paper elaborates the various manufacturing processes carried on various biocompatible metallic and nonmetallic customised implantable devices. Conclusion Ti-6Al-4V alloy is broadly used for biomedical implants, but in this alloy, Vanadium is toxic so this alloy is not compatible for implants. The attention of researchers is towards the non toxic and suitable biocompatible materials. For this reason, a novel approach was developed in order to enhance the mechanical properties of this material. . The development of incremental forming technique can improve the formability of existing alloys and may meet the current strict requirements for performance of dies and punches.

Influence of Fiber Orientation on Single-Point Cutting Fracture Behavior of Carbon-Fiber/Epoxy Prepreg Sheets

Directory of Open Access Journals (Sweden)

Yingying Wei

2015-10-01

Full Text Available The purpose of this article is to investigate the influences of carbon fibers on the fracture mechanism of carbon fibers both in macroscopic view and microscopic view by using single-point flying cutting method. Cutting tools with three different materials were used in this research, namely, PCD (polycrystalline diamond tool, CVD (chemical vapor deposition diamond thin film coated carbide tool and uncoated carbide tool. The influence of fiber orientation on the cutting force and fracture topography were analyzed and conclusions were drawn that cutting forces are not affected by cutting speeds but significantly influenced by the fiber orientation. Cutting forces presented smaller values in the fiber orientation of 0/180° and 15/165° but the highest one in 30/150°. The fracture mechanism of carbon fibers was studied in different cutting conditions such as 0° orientation angle, 90° orientation angle, orientation angles along fiber direction, and orientation angles inverse to the fiber direction. In addition, a prediction model on the cutting defects of carbon fiber reinforced plastic was established based on acoustic emission (AE signals.

Influence of Fiber Orientation on Single-Point Cutting Fracture Behavior of Carbon-Fiber/Epoxy Prepreg Sheets.

Science.gov (United States)

Wei, Yingying; An, Qinglong; Cai, Xiaojiang; Chen, Ming; Ming, Weiwei

2015-10-02

The purpose of this article is to investigate the influences of carbon fibers on the fracture mechanism of carbon fibers both in macroscopic view and microscopic view by using single-point flying cutting method. Cutting tools with three different materials were used in this research, namely, PCD (polycrystalline diamond) tool, CVD (chemical vapor deposition) diamond thin film coated carbide tool and uncoated carbide tool. The influence of fiber orientation on the cutting force and fracture topography were analyzed and conclusions were drawn that cutting forces are not affected by cutting speeds but significantly influenced by the fiber orientation. Cutting forces presented smaller values in the fiber orientation of 0/180° and 15/165° but the highest one in 30/150°. The fracture mechanism of carbon fibers was studied in different cutting conditions such as 0° orientation angle, 90° orientation angle, orientation angles along fiber direction, and orientation angles inverse to the fiber direction. In addition, a prediction model on the cutting defects of carbon fiber reinforced plastic was established based on acoustic emission (AE) signals.

Single-electron charging effects

International Nuclear Information System (INIS)

Ruggiero, S.T.

1990-01-01

The status of our project on single-electron tunneling is at this point excellent. As outlined in our original proposal, a key goal in the development of this project was the demonstration and exploration of the microwave properties of single-electron systems. As discussed here, such work has to date been carried out

A multi points ultrasonic detection method for material flow of belt conveyor

Science.gov (United States)

Zhang, Li; He, Rongjun

2018-03-01

For big detection error of single point ultrasonic ranging technology used in material flow detection of belt conveyor when coal distributes unevenly or is large, a material flow detection method of belt conveyor is designed based on multi points ultrasonic counter ranging technology. The method can calculate approximate sectional area of material by locating multi points on surfaces of material and belt, in order to get material flow according to running speed of belt conveyor. The test results show that the method has smaller detection error than single point ultrasonic ranging technology under the condition of big coal with uneven distribution.

[Brief analysis of professor YAN Jie's academic thought on functional dyspepsia treated with acupuncture and moxibustion].

Science.gov (United States)

Tan, Tao; Yan, Jie

2016-01-01

The brief discussion is introduced in the paper on the academic thought of professor YAN Jie, the contemporary famous TCM doctor, on functional dyspepsia treated with acupuncture and moxibustion. Treatment based on "the three-regional acupoint selection" is applied to professor YAN's treatment for functional dyspepsia, in which, acupuncture is on Sibai (ST 2), Liangmen (ST 21) and Zusanli (ST 36), and the supplementary points are added accordingly. The academic thought is described as the combination of acupuncture and moxibustion based on strengthening healthy qi, supplemented by soothing the liver and psychological counseling. Also, an example is provided.

Single ventricle cardiac defect

International Nuclear Information System (INIS)

Eren, B.; Turkmen, N.; Fedakar, R.; Cetin, V.

2010-01-01

Single ventricle heart is defined as a rare cardiac abnormality with a single ventricle chamber involving diverse functional and physiological defects. Our case is of a ten month-old baby boy who died shortly after admission to the hospital due to vomiting and diarrhoea. Autopsy findings revealed cyanosis of finger nails and ears. Internal examination revealed; large heart, weighing 60 grams, single ventricle, without a septum and upper membranous part. Single ventricle is a rare pathology, hence, this paper aims to discuss this case from a medico-legal point of view. (author)

Point defects in platinum

International Nuclear Information System (INIS)

Piercy, G.R.

1960-01-01

An investigation was made of the mobility and types of point defect introduced in platinum by deformation in liquid nitrogen, quenching into water from 1600 o C, or reactor irradiation at 50 o C. In all cases the activation energy for motion of the defect was determined from measurements of electrical resistivity. Measurements of density, hardness, and x-ray line broadening were also made there applicable. These experiments indicated that the principal defects remaining in platinum after irradiation were single vacant lattice sites and after quenching were pairs of vacant lattice sites. Those present after deformation In liquid nitrogen were single vacant lattice sites and another type of defect, perhaps interstitial atoms. (author)

Microcurrent Point Stimulation Applied to Lower Back Acupuncture Points for the Treatment of Nonspecific Neck Pain.

Science.gov (United States)

Armstrong, Kelly; Gokal, Raman; Chevalier, Antoine; Todorsky, William; Lim, Mike

2017-04-01

Although acupuncture and microcurrent are widely used for chronic pain, there remains considerable controversy as to their therapeutic value for neck pain. We aimed to determine the effect size of microcurrent applied to lower back acupuncture points to assess the impact on the neck pain. This was a cohort analysis of treatment outcomes pre- and postmicrocurrent stimulation, involving 34 patients with a history of nonspecific chronic neck pain. Consenting patients were enrolled from a group of therapists attending educational seminars and were asked to report pain levels pre-post and 48 hours after a single MPS application. Direct current microcurrent point stimulation (MPS) applied to standardized lower back acupuncture protocol points was used. Evaluations entailed a baseline visual analog scale (VAS) pain scale assessment, using a VAS, which was repeated twice after therapy, once immediately postelectrotherapy and again after a 48-h follow-up period. All 34 patients received a single MPS session. Results were analyzed using paired t tests. Results and Outcomes: Pain intensity showed an initial statistically significant reduction of 68% [3.9050 points; 95% CI (2.9480, 3.9050); p = 0.0001], in mean neck pain levels after standard protocol treatment, when compared to initial pain levels. There was a further statistically significant reduction of 35% in mean neck pain levels at 48 h when compared to pain levels immediately after standard protocol treatment [0.5588 points; 95% CI (0.2001, 0.9176); p = 0.03], for a total average pain relief of 80%. The positive results in this study could have applications for those patients impacted by chronic neck pain.

Flat Coalgebraic Fixed Point Logics

Science.gov (United States)

Schröder, Lutz; Venema, Yde

Fixed point logics are widely used in computer science, in particular in artificial intelligence and concurrency. The most expressive logics of this type are the μ-calculus and its relatives. However, popular fixed point logics tend to trade expressivity for simplicity and readability, and in fact often live within the single variable fragment of the μ-calculus. The family of such flat fixed point logics includes, e.g., CTL, the *-nesting-free fragment of PDL, and the logic of common knowledge. Here, we extend this notion to the generic semantic framework of coalgebraic logic, thus covering a wide range of logics beyond the standard μ-calculus including, e.g., flat fragments of the graded μ-calculus and the alternating-time μ-calculus (such as ATL), as well as probabilistic and monotone fixed point logics. Our main results are completeness of the Kozen-Park axiomatization and a timed-out tableaux method that matches ExpTime upper bounds inherited from the coalgebraic μ-calculus but avoids using automata.

Equations for arithmetic pointed tori

NARCIS (Netherlands)

Sijsling, J.R.

2010-01-01

In 1983, Kisao Takeuchi enumerated all 71 arithmetic (1;e)-groups. This is a special set of discrete subgroups of SL(2,R) of finite covolume and signature (1;e). The corresponding quotients of the upper half plane (called (1;e)-curves) have genus equal to 1 and a single elliptic point of order e.

Prediction and control of pillow defect in single point incremental forming using numerical simulations

International Nuclear Information System (INIS)

Isidore, B. B. Lemopi; Hussain, G.; Khan, Wasim A.; Shamachi, S. Pourhassan

2016-01-01

Pillows formed at the center of sheets in Single point incremental forming (SPIF) are fabrication defects which adversely affect the geometrical accuracy and formability of manufactured parts. This study is focused on using FEA as a tool to predict and control pillowing in SPIF by varying tool size and shape. 3D Finite element analysis (FEA) and experiments are carried out using annealed Aluminum 1050. From FEA, it is found out that the stress/strain state in the immediate vicinity of the forming tool in the transverse direction plays a determinant role on sheet pillowing. Furthermore, pillow height increases as compression in the sheet-plane increases. The nature of in-plane stresses in the transverse direction varies from compressive to tensile as the tool-end geometry is changed from spherical to flat. Additionally, the magnitude of corresponding in-plane stresses decreases as the tool radius increases. According to measurements from the FEA model, flat end tools and large radii both retard pillow formation. However, the influence of changing tool end shape from hemispherical to flat is observed to be more important than the effect of varying tool radius, because the deformation zone remains in tension in the transverse direction while forming with flat end tools. These findings are verified by conducting a set of experiments. A fair agreement between the FEM and empirical results show that FEM can be employed as a tool to predict and control the pillow defect in SPIF.

Prediction and control of pillow defect in single point incremental forming using numerical simulations

Energy Technology Data Exchange (ETDEWEB)

Isidore, B. B. Lemopi [Eastern Mediterranean University, Gazimagusa (Turkmenistan); Hussain, G.; Khan, Wasim A. [GIK Institute of Engineering, Swabi (Pakistan); Shamachi, S. Pourhassan [University of Minho, Guimaraes (Portugal)

2016-05-15

Pillows formed at the center of sheets in Single point incremental forming (SPIF) are fabrication defects which adversely affect the geometrical accuracy and formability of manufactured parts. This study is focused on using FEA as a tool to predict and control pillowing in SPIF by varying tool size and shape. 3D Finite element analysis (FEA) and experiments are carried out using annealed Aluminum 1050. From FEA, it is found out that the stress/strain state in the immediate vicinity of the forming tool in the transverse direction plays a determinant role on sheet pillowing. Furthermore, pillow height increases as compression in the sheet-plane increases. The nature of in-plane stresses in the transverse direction varies from compressive to tensile as the tool-end geometry is changed from spherical to flat. Additionally, the magnitude of corresponding in-plane stresses decreases as the tool radius increases. According to measurements from the FEA model, flat end tools and large radii both retard pillow formation. However, the influence of changing tool end shape from hemispherical to flat is observed to be more important than the effect of varying tool radius, because the deformation zone remains in tension in the transverse direction while forming with flat end tools. These findings are verified by conducting a set of experiments. A fair agreement between the FEM and empirical results show that FEM can be employed as a tool to predict and control the pillow defect in SPIF.

X-Ray Radiography of Three-Point Bending of Single Human Trabecula

Czech Academy of Sciences Publication Activity Database

Jiroušek, Ondřej; Doktor, Tomáš; Kytýř, Daniel; Zlámal, Petr

2012-01-01

Roč. 45, S1 (2012), s. 261-261 ISSN 0021-9290 R&D Projects: GA ČR(CZ) GAP105/10/2305 Institutional support: RVO:68378297 Keywords : microspheres * strain measurement * three-point bending * trabecular bone * X-ray radiography Subject RIV: FI - Traumatology, Orthopedics Impact factor: 2.716, year: 2012

Point kernels and superposition methods for scatter dose calculations in brachytherapy

International Nuclear Information System (INIS)

Carlsson, A.K.

2000-01-01

Point kernels have been generated and applied for calculation of scatter dose distributions around monoenergetic point sources for photon energies ranging from 28 to 662 keV. Three different approaches for dose calculations have been compared: a single-kernel superposition method, a single-kernel superposition method where the point kernels are approximated as isotropic and a novel 'successive-scattering' superposition method for improved modelling of the dose from multiply scattered photons. An extended version of the EGS4 Monte Carlo code was used for generating the kernels and for benchmarking the absorbed dose distributions calculated with the superposition methods. It is shown that dose calculation by superposition at and below 100 keV can be simplified by using isotropic point kernels. Compared to the assumption of full in-scattering made by algorithms currently in clinical use, the single-kernel superposition method improves dose calculations in a half-phantom consisting of air and water. Further improvements are obtained using the successive-scattering superposition method, which reduces the overestimates of dose close to the phantom surface usually associated with kernel superposition methods at brachytherapy photon energies. It is also shown that scatter dose point kernels can be parametrized to biexponential functions, making them suitable for use with an effective implementation of the collapsed cone superposition algorithm. (author)

Detecting Change-Point via Saddlepoint Approximations

Institute of Scientific and Technical Information of China (English)

Zhaoyuan LI; Maozai TIAN

2017-01-01

It's well-known that change-point problem is an important part of model statistical analysis.Most of the existing methods are not robust to criteria of the evaluation of change-point problem.In this article,we consider "mean-shift" problem in change-point studies.A quantile test of single quantile is proposed based on saddlepoint approximation method.In order to utilize the information at different quantile of the sequence,we further construct a "composite quantile test" to calculate the probability of every location of the sequence to be a change-point.The location of change-point can be pinpointed rather than estimated within a interval.The proposed tests make no assumptions about the functional forms of the sequence distribution and work sensitively on both large and small size samples,the case of change-point in the tails,and multiple change-points situation.The good performances of the tests are confirmed by simulations and real data analysis.The saddlepoint approximation based distribution of the test statistic that is developed in the paper is of independent interest and appealing.This finding may be of independent interest to the readers in this research area.

Cochlear implant effectiveness in postlingual single-sided deaf individuals: what's the point?

Science.gov (United States)

Finke, Mareike; Bönitz, Hanna; Lyxell, Björn; Illg, Angelika

2017-06-01

By extending the indication criteria for cochlear implants (CI), the population of CI candidates increased in age, as well as range and type of hearing loss. This qualitative study identified factors that contributed to seek CI treatment in single-sided deaf individuals and gained insights how single-sided deafness (SSD) and hearing with a CI affect their lives. An open-ended questionnaire and a standardised inventory (IOI-HA) were used. Qualitative data reflecting the reasons to seek CI treatment and the individual experiences after CI switch-on were collected. A total of 19 postlingually deafened single-sided deaf CI users. Participants use their CI daily and stated that their life satisfaction increased since CI activation. The analysis of the qualitative data revealed four core categories: sound localisation, tinnitus and noise sensitivity, fear to lose the second ear and quality of life. Our results show how strongly and diversely quality of hearing and quality of life is affected by acquired SSD and improved after CI activation. Our data suggest that the fear of hearing loss (HL) on the normal hearing (NH) ear is an important but so far neglected reason to seek treatment with a CI in individuals with postlingual SSD.

A General Schema for Constructing One-Point Bases in the Lambda Calculus

DEFF Research Database (Denmark)

Goldberg, Mayer

2001-01-01

In this paper, we present a schema for constructing one-point bases for recursively enumerable sets of lambda terms. The novelty of the approach is that we make no assumptions about the terms for which the one-point basis is constructed: They need not be combinators and they may contain constants...... and free variables. The significance of the construction is twofold: In the context of the lambda calculus, it characterises one-point bases as ways of ``packaging'' sets of terms into a single term; And in the context of realistic programming languages, it implies that we can define a single procedure...

Simultaneous measurement of passage through the restriction point and MCM loading in single cells

Science.gov (United States)

Håland, T. W.; Boye, E.; Stokke, T.; Grallert, B.; Syljuåsen, R. G.

2015-01-01

Passage through the Retinoblastoma protein (RB1)-dependent restriction point and the loading of minichromosome maintenance proteins (MCMs) are two crucial events in G1-phase that help maintain genome integrity. Deregulation of these processes can cause uncontrolled proliferation and cancer development. Both events have been extensively characterized individually, but their relative timing and inter-dependence remain less clear. Here, we describe a novel method to simultaneously measure MCM loading and passage through the restriction point. We exploit that the RB1 protein is anchored in G1-phase but is released when hyper-phosphorylated at the restriction point. After extracting cells with salt and detergent before fixation we can simultaneously measure, by flow cytometry, the loading of MCMs onto chromatin and RB1 binding to determine the order of the two events in individual cells. We have used this method to examine the relative timing of the two events in human cells. Whereas in BJ fibroblasts released from G0-phase MCM loading started mainly after the restriction point, in a significant fraction of exponentially growing BJ and U2OS osteosarcoma cells MCMs were loaded in G1-phase with RB1 anchored, demonstrating that MCM loading can also start before the restriction point. These results were supported by measurements in synchronized U2OS cells. PMID:26250117

A Direct Maximum Power Point Tracking Method for Single-Phase Grid Connected PV Inverters

DEFF Research Database (Denmark)

EL Aamri, Faicel; Maker, Hattab; Sera, Dezso

2018-01-01

in dynamic conditions, especially in low irradiance when the measurement of signals becomes more sensitive to noise. The proposed MPPT is designed for single-phase single-stage grid-connected PV inverters, and is based on estimating the instantaneous PV power and voltage ripples, using second...

High precision wavefront control in point spread function engineering for single emitter localization

Science.gov (United States)

Siemons, M.; Hulleman, C. N.; Thorsen, R. Ø.; Smith, C. S.; Stallinga, S.

2018-04-01

Point Spread Function (PSF) engineering is used in single emitter localization to measure the emitter position in 3D and possibly other parameters such as the emission color or dipole orientation as well. Advanced PSF models such as spline fits to experimental PSFs or the vectorial PSF model can be used in the corresponding localization algorithms in order to model the intricate spot shape and deformations correctly. The complexity of the optical architecture and fit model makes PSF engineering approaches particularly sensitive to optical aberrations. Here, we present a calibration and alignment protocol for fluorescence microscopes equipped with a spatial light modulator (SLM) with the goal of establishing a wavefront error well below the diffraction limit for optimum application of complex engineered PSFs. We achieve high-precision wavefront control, to a level below 20 m$\\lambda$ wavefront aberration over a 30 minute time window after the calibration procedure, using a separate light path for calibrating the pixel-to-pixel variations of the SLM, and alignment of the SLM with respect to the optical axis and Fourier plane within 3 $\\mu$m ($x/y$) and 100 $\\mu$m ($z$) error. Aberrations are retrieved from a fit of the vectorial PSF model to a bead $z$-stack and compensated with a residual wavefront error comparable to the error of the SLM calibration step. This well-calibrated and corrected setup makes it possible to create complex `3D+$\\lambda$' PSFs that fit very well to the vectorial PSF model. Proof-of-principle bead experiments show precisions below 10~nm in $x$, $y$, and $\\lambda$, and below 20~nm in $z$ over an axial range of 1 $\\mu$m with 2000 signal photons and 12 background photons.

Effects of junction resistance and counterelectrode material on point-contact tunneling into single- and polycrystalline YBa/sub 2/Cu/sub 3/O/sub 7-y/

Energy Technology Data Exchange (ETDEWEB)

Moog, E.R.; Hawley, M.E.; Gray, K.E.; Liu, J.Z.; Hinks, D.G.; Capone, D.W. II; Downey, J.

1988-06-01

The effects of junction resistance and counterelectrode material on the results of point-contact tunneling studies into single- and polycrystalline YBa/sub 2/Cu/sub 3/O/sub 7-y/ are illustrated. Although reasonably symmetric I(V) curves predominantly indicate energy gap values /Delta/ /approx/ 20 meV, large asymmetries are often found for high-resistance junctions. Very low-resistance junctions show the expected behavior of pure metallic bridge and indicate /Delta/ /approx/ 25-30 meV.

Single-photon imaging

CERN Document Server

Seitz, Peter

2011-01-01

The acquisition and interpretation of images is a central capability in almost all scientific and technological domains. In particular, the acquisition of electromagnetic radiation, in the form of visible light, UV, infrared, X-ray, etc. is of enormous practical importance. The ultimate sensitivity in electronic imaging is the detection of individual photons. With this book, the first comprehensive review of all aspects of single-photon electronic imaging has been created. Topics include theoretical basics, semiconductor fabrication, single-photon detection principles, imager design and applications of different spectral domains. Today, the solid-state fabrication capabilities for several types of image sensors has advanced to a point, where uncoooled single-photon electronic imaging will soon become a consumer product. This book is giving a specialist´s view from different domains to the forthcoming “single-photon imaging” revolution. The various aspects of single-photon imaging are treated by internati...

Guided Discovery of the Nine-Point Circle Theorem and Its Proof

Science.gov (United States)

Buchbinder, Orly

2018-01-01

The nine-point circle theorem is one of the most beautiful and surprising theorems in Euclidean geometry. It establishes an existence of a circle passing through nine points, all of which are related to a single triangle. This paper describes a set of instructional activities that can help students discover the nine-point circle theorem through…

Floating point only SIMD instruction set architecture including compare, select, Boolean, and alignment operations

Science.gov (United States)

Gschwind, Michael K [Chappaqua, NY

2011-03-01

Mechanisms for implementing a floating point only single instruction multiple data instruction set architecture are provided. A processor is provided that comprises an issue unit, an execution unit coupled to the issue unit, and a vector register file coupled to the execution unit. The execution unit has logic that implements a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA). The floating point vector registers of the vector register file store both scalar and floating point values as vectors having a plurality of vector elements. The processor may be part of a data processing system.

Lane Determination with GPS Precise Point Positioning

NARCIS (Netherlands)

Knoop, V.L.; de Bakker, P.F.; Tiberius, C.C.J.M.; van Arem, B.

2017-01-01

Modern intelligent transport solutions can achieve an improvement of traffic flow on motorways. With lane-specific measurements and lane-specific control, more measures are possible. Single frequency precise point positioning (PPP) is a newly developed and affordable technique to achieve an

Single lens laser beam shaper

Science.gov (United States)

Liu, Chuyu [Newport News, VA; Zhang, Shukui [Yorktown, VA

2011-10-04

A single lens bullet-shaped laser beam shaper capable of redistributing an arbitrary beam profile into any desired output profile comprising a unitary lens comprising: a convex front input surface defining a focal point and a flat output portion at the focal point; and b) a cylindrical core portion having a flat input surface coincident with the flat output portion of the first input portion at the focal point and a convex rear output surface remote from the convex front input surface.

SharePoint 2010 at Work Tricks, Traps, and Bold Opinions

CERN Document Server

Miller, Mark; Anderson, Marc; Rogers, Laura; Abraham, Kerri; Buren, Sadalit; Mastykarz, Waldek; Alexander, Eric; Bautz, Alexander; Howard, Jim; Allen, Peter

2012-01-01

If you're a SharePoint site manager or administrator, you finally have a handy single-source reference to help you through the tough SharePoint learning curve. Written by Mark Miller and his stable of well-known contributors at EndUserSharePoint.com, this book contains the most helpful articles from this popular site-fully updated for SharePoint 2010. Each chapter focuses on core issues that vex SharePoint administrators when it comes to setting up and managing sites. You'll learn tried-and-true solutions for creating charts and graphs, joining views in SharePoint lists, building a SharePoin

Visit of Peters Higgs at Point 2 ALICE Experiment - British theoretical physicist, He worked on proposals to unify the weak and the electromagnetic forces into a single electroweak theory, The Boson of Higgs.

CERN Multimedia

Mona Schweizer

2008-01-01

Visit of Peters Higgs at Point 2 ALICE Experiment - British theoretical physicist, He worked on proposals to unify the weak and the electromagnetic forces into a single electroweak theory, The Boson of Higgs.

Single-photon imaging

International Nuclear Information System (INIS)

Seitz, Peter; Theuwissen, Albert J.P.

2011-01-01

The acquisition and interpretation of images is a central capability in almost all scientific and technological domains. In particular, the acquisition of electromagnetic radiation, in the form of visible light, UV, infrared, X-ray, etc. is of enormous practical importance. The ultimate sensitivity in electronic imaging is the detection of individual photons. With this book, the first comprehensive review of all aspects of single-photon electronic imaging has been created. Topics include theoretical basics, semiconductor fabrication, single-photon detection principles, imager design and applications of different spectral domains. Today, the solid-state fabrication capabilities for several types of image sensors has advanced to a point, where uncooled single-photon electronic imaging will soon become a consumer product. This book is giving a specialist's view from different domains to the forthcoming ''single-photon imaging'' revolution. The various aspects of single-photon imaging are treated by internationally renowned, leading scientists and technologists who have all pioneered their respective fields. (orig.)

CAN MARKETING SUPPORT THE IMPLEMENTATION OF EFFECTIVE EGOVERNMENT? ANALYSIS OF THE SINGLE POINT OF ACCESS PORTAL FOR ROMANIAN ELECTRONIC PUBLIC SERVICES

Directory of Open Access Journals (Sweden)

Velicu Bogdan Calin

2011-12-01

Full Text Available The advances in technology hold great potential for helping Romanian government respond to its challenges namely, better service delivery, better procurement, efficient working and better communication with citizens and businesses. While the European Commission develops the main strategies on eGovernment, every member state has the freedom to identify its own necessities and decide according to specific social, administrative and economic context. Designing, cost setting, choosing the best supply channels or communicating with involved actors, are all marketing instruments which, if used accordingly, can ensure modern and efficient public services. This paper presents an analysis of the degree of development of public services available at the www.e-guvernare.ro portal, the single point of access for specific Romanian electronic public services.

A critical analysis of the tender points in fibromyalgia.

Science.gov (United States)

Harden, R Norman; Revivo, Gadi; Song, Sharon; Nampiaparampil, Devi; Golden, Gary; Kirincic, Marie; Houle, Timothy T

2007-03-01

To pilot methodologies designed to critically assess the American College of Rheumatology's (ACR) diagnostic criteria for fibromyalgia. Prospective, psychophysical testing. An urban teaching hospital. Twenty-five patients with fibromyalgia and 31 healthy controls (convenience sample). Pressure pain threshold was determined at the 18 ACR tender points and five sham points using an algometer (dolorimeter). The patients "algometric total scores" (sums of the patients' average pain thresholds at the 18 tender points) were derived, as well as pain thresholds across sham points. The "algometric total score" could differentiate patients with fibromyalgia from normals with an accuracy of 85.7% (P pain across sham points than across ACR tender points, sham points also could be used for diagnosis (85.7%; Ps tested vs other painful conditions. The points specified by the ACR were only modestly superior to sham points in making the diagnosis. Most importantly, this pilot suggests single points, smaller groups of points, or sham points may be as effective in diagnosing fibromyalgia as the use of all 18 points, and suggests methodologies to definitively test that hypothesis.

An equilibrium-point model of electromyographic patterns during single-joint movements based on experimentally reconstructed control signals.

Science.gov (United States)

Latash, M L; Goodman, S R

1994-01-01

The purpose of this work has been to develop a model of electromyographic (EMG) patterns during single-joint movements based on a version of the equilibrium-point hypothesis, a method for experimental reconstruction of the joint compliant characteristics, the dual-strategy hypothesis, and a kinematic model of movement trajectory. EMG patterns are considered emergent properties of hypothetical control patterns that are equally affected by the control signals and peripheral feedback reflecting actual movement trajectory. A computer model generated the EMG patterns based on simulated movement kinematics and hypothetical control signals derived from the reconstructed joint compliant characteristics. The model predictions have been compared to published recordings of movement kinematics and EMG patterns in a variety of movement conditions, including movements over different distances, at different speeds, against different-known inertial loads, and in conditions of possible unexpected decrease in the inertial load. Changes in task parameters within the model led to simulated EMG patterns qualitatively similar to the experimentally recorded EMG patterns. The model's predictive power compares it favourably to the existing models of the EMG patterns. Copyright © 1994. Published by Elsevier Ltd.

An application of eddy current damping effect on single point diamond turning of titanium alloys

Science.gov (United States)

Yip, W. S.; To, S.

2017-11-01

Titanium alloys Ti6Al4V (TC4) have been popularly applied in many industries. They have superior material properties including an excellent strength-to-weight ratio and corrosion resistance. However, they are regarded as difficult to cut materials; serious tool wear, a high level of cutting vibration and low surface integrity are always involved in machining processes especially in ultra-precision machining (UPM). In this paper, a novel hybrid machining technology using an eddy current damping effect is firstly introduced in UPM to suppress machining vibration and improve the machining performance of titanium alloys. A magnetic field was superimposed on samples during single point diamond turning (SPDT) by exposing the samples in between two permanent magnets. When the titanium alloys were rotated within a magnetic field in the SPDT, an eddy current was generated through a stationary magnetic field inside the titanium alloys. An eddy current generated its own magnetic field with the opposite direction of the external magnetic field leading a repulsive force, compensating for the machining vibration induced by the turning process. The experimental results showed a remarkable improvement in cutting force variation, a significant reduction in adhesive tool wear and an extreme long chip formation in comparison to normal SPDT of titanium alloys, suggesting the enhancement of the machinability of titanium alloys using an eddy current damping effect. An eddy current damping effect was firstly introduced in the area of UPM to deliver the results of outstanding machining performance.

An application of eddy current damping effect on single point diamond turning of titanium alloys

International Nuclear Information System (INIS)

Yip, W S; To, S

2017-01-01

Titanium alloys Ti6Al4V (TC4) have been popularly applied in many industries. They have superior material properties including an excellent strength-to-weight ratio and corrosion resistance. However, they are regarded as difficult to cut materials; serious tool wear, a high level of cutting vibration and low surface integrity are always involved in machining processes especially in ultra-precision machining (UPM). In this paper, a novel hybrid machining technology using an eddy current damping effect is firstly introduced in UPM to suppress machining vibration and improve the machining performance of titanium alloys. A magnetic field was superimposed on samples during single point diamond turning (SPDT) by exposing the samples in between two permanent magnets. When the titanium alloys were rotated within a magnetic field in the SPDT, an eddy current was generated through a stationary magnetic field inside the titanium alloys. An eddy current generated its own magnetic field with the opposite direction of the external magnetic field leading a repulsive force, compensating for the machining vibration induced by the turning process. The experimental results showed a remarkable improvement in cutting force variation, a significant reduction in adhesive tool wear and an extreme long chip formation in comparison to normal SPDT of titanium alloys, suggesting the enhancement of the machinability of titanium alloys using an eddy current damping effect. An eddy current damping effect was firstly introduced in the area of UPM to deliver the results of outstanding machining performance. (paper)

Does the nervous system use equilibrium-point control to guide single and multiple joint movements?

Science.gov (United States)

Bizzi, E; Hogan, N; Mussa-Ivaldi, F A; Giszter, S

1992-12-01

The hypothesis that the central nervous system (CNS) generates movement as a shift of the limb's equilibrium posture has been corroborated experimentally in studies involving single- and multijoint motions. Posture may be controlled through the choice of muscle length-tension curve that set agonist-antagonist torque-angle curves determining an equilibrium position for the limb and the stiffness about the joints. Arm trajectories seem to be generated through a control signal defining a series of equilibrium postures. The equilibrium-point hypothesis drastically simplifies the requisite computations for multijoint movements and mechanical interactions with complex dynamic objects in the environment. Because the neuromuscular system is springlike, the instantaneous difference between the arm's actual position and the equilibrium position specified by the neural activity can generate the requisite torques, avoiding the complex "inverse dynamic" problem of computing the torques at the joints. The hypothesis provides a simple, unified description of posture and movement as well as contact control task performance, in which the limb must exert force stably and do work on objects in the environment. The latter is a surprisingly difficult problem, as robotic experience has shown. The prior evidence for the hypothesis came mainly from psychophysical and behavioral experiments. Our recent work has shown that microstimulation of the frog spinal cord's premotoneural network produces leg movements to various positions in the frog's motor space. The hypothesis can now be investigated in the neurophysiological machinery of the spinal cord.

MIMIC: An Innovative Methodology for Determining Mobile Laser Scanning System Point Density

Directory of Open Access Journals (Sweden)

Conor Cahalane

2014-08-01

Full Text Available Understanding how various Mobile Mapping System (MMS laser hardware configurations and operating parameters exercise different influence on point density is important for assessing system performance, which in turn facilitates system design and MMS benchmarking. Point density also influences data processing, as objects that can be recognised using automated algorithms generally require a minimum point density. Although obtaining the necessary point density impacts on hardware costs, survey time and data storage requirements, a method for accurately and rapidly assessing MMS performance is lacking for generic MMSs. We have developed a method for quantifying point clouds collected by an MMS with respect to known objects at specified distances using 3D surface normals, 2D geometric formulae and line drawing algorithms. These algorithms were combined in a system called the Mobile Mapping Point Density Calculator (MIMIC and were validated using point clouds captured by both a single scanner and a dual scanner MMS. Results from MIMIC were promising: when considering the number of scan profiles striking the target, the average error equated to less than 1 point per scan profile. These tests highlight that MIMIC is capable of accurately calculating point density for both single and dual scanner MMSs.

C-point and V-point singularity lattice formation and index sign conversion methods

Science.gov (United States)

Kumar Pal, Sushanta; Ruchi; Senthilkumaran, P.

2017-06-01

The generic singularities in an ellipse field are C-points namely stars, lemons and monstars in a polarization distribution with C-point indices (-1/2), (+1/2) and (+1/2) respectively. Similar to C-point singularities, there are V-point singularities that occur in a vector field and are characterized by Poincare-Hopf index of integer values. In this paper we show that the superposition of three homogenously polarized beams in different linear states leads to the formation of polarization singularity lattice. Three point sources at the focal plane of the lens are used to create three interfering plane waves. A radial/azimuthal polarization converter (S-wave plate) placed near the focal plane modulates the polarization states of the three beams. The interference pattern is found to host C-points and V-points in a hexagonal lattice. The C-points occur at intensity maxima and V-points occur at intensity minima. Modulating the state of polarization (SOP) of three plane waves from radial to azimuthal does not essentially change the nature of polarization singularity lattice as the Poincare-Hopf index for both radial and azimuthal polarization distributions is (+1). Hence a transformation from a star to a lemon is not trivial, as such a transformation requires not a single SOP change, but a change in whole spatial SOP distribution. Further there is no change in the lattice structure and the C- and V-points appear at locations where they were present earlier. Hence to convert an interlacing star and V-point lattice into an interlacing lemon and V-point lattice, the interferometer requires modification. We show for the first time a method to change the polarity of C-point and V-point indices. This means that lemons can be converted into stars and stars can be converted into lemons. Similarly the positive V-point can be converted to negative V-point and vice versa. The intensity distribution in all these lattices is invariant as the SOPs of the three beams are changed in an

PIV study of non-Marangoni surface flows in thin liquid films induced by single- and multi-point thermodes

Science.gov (United States)

Cui, Nai-Yi; Wang, Song-Po

2018-03-01

The non-Marangoni directional flows, which can occur in only very thin liquid films, have been studied using particle image velocimetry techniques. Single- and multi-point thermodes have been used in this study for generating the flows. The results show that the direction of these flows is governed by the variation trend of the thickness of the film and the shape of the temperature profile. A hot thermode always drives a thick-to-thin flow, whereas a cold thermode always drives a flow in the opposite direction. Increasing the temperature difference between the thermode and the ambience, or decreasing the thickness of the liquid film, can accelerate the flow speed. However, the flow speed cannot exceed an upper limit. When more than one thermode was used, different flow patterns, including thick-to-thin streams driven by hot thermodes and thin-to-thick streams driven by cold thermodes, could be formed. The experimental results strongly suggest that these flows were not driven by thermo-capillary forces but by a newly proposed thermo-dynamic mechanism.

Multi-lane detection based on multiple vanishing points detection

Science.gov (United States)

Li, Chuanxiang; Nie, Yiming; Dai, Bin; Wu, Tao

2015-03-01

Lane detection plays a significant role in Advanced Driver Assistance Systems (ADAS) for intelligent vehicles. In this paper we present a multi-lane detection method based on multiple vanishing points detection. A new multi-lane model assumes that a single lane, which has two approximately parallel boundaries, may not parallel to others on road plane. Non-parallel lanes associate with different vanishing points. A biological plausibility model is used to detect multiple vanishing points and fit lane model. Experimental results show that the proposed method can detect both parallel lanes and non-parallel lanes.

Multi-point laser ignition device

Energy Technology Data Exchange (ETDEWEB)

McIntyre, Dustin L.; Woodruff, Steven D.

2017-01-17

A multi-point laser device comprising a plurality of optical pumping sources. Each optical pumping source is configured to create pumping excitation energy along a corresponding optical path directed through a high-reflectivity mirror and into substantially different locations within the laser media thereby producing atomic optical emissions at substantially different locations within the laser media and directed along a corresponding optical path of the optical pumping source. An output coupler and one or more output lenses are configured to produce a plurality of lasing events at substantially different times, locations or a combination thereof from the multiple atomic optical emissions produced at substantially different locations within the laser media. The laser media is a single continuous media, preferably grown on a single substrate.

Study on the Single Scattering of Elastic Waves by a Cylindrical Fiber with a Partially Imperfect Bonding Using the Collocation Point Method

Directory of Open Access Journals (Sweden)

Jun Zhang

2018-01-01

Full Text Available The single scattering of P- and SV-waves by a cylindrical fiber with a partially imperfect bonding to the surrounding matrix is investigated, which benefits the characterization of the behavior of elastic waves in composite materials. The imperfect interface is modelled by the spring model. To solve the corresponding single scattering problem, a collocation point (CP method is introduced. Based on this method, influence of various aspects of the imperfect interface on the scattering of P- and SV-waves is studied. Results indicate that (i the total scattering cross section (SCS is almost symmetric about the axis α=π/2 with respect to the location (α of the imperfect interface, (ii imperfect interfaces located at α=0 and α=π highly reduce the total SCS under a P-wave incidence and imperfect interfaces located at α=π/2 reduce the total SCS most significantly under SV-incidence, and (iii under a P-wave incidence the SCS has a high sensitivity to the bonding level of imperfect interfaces when α is small, while it becomes more sensitive to the bonding level when α is larger under SV-wave incidence.

Geometry effect on the behaviour of single and glue-laminated glass fibre reinforced polymer composite sandwich beams loaded in four-point bending

International Nuclear Information System (INIS)

Awad, Ziad K.; Aravinthan, Thiru; Manalo, Allan

2012-01-01

Highlights: ► Investigated the behaviour of single and glue-laminated GFRP sandwich beam. ► Effect of shear span to depth was a key factor affecting the overall behaviour. ► Comparison with prediction models gave reasonable results in specific regions. ► A failure map was developed to identify the shear and flexural failures of panels. -- Abstract: The research investigated the behaviour of single and glue laminated glass fibre reinforced polymer (GFRP) composite sandwich beams considering different spans and beam cross sections. The composite sandwich beams with different thicknesses (1, 2, 3, 4, and 5 sandwich layers) have been tested in four-point static flexural test with different shear span to depth ratio (a/d). The a/d ratios showed a direct effect on the flexural and shear behaviour. The capacity of the beam decreased with increasing a/d. Various failure modes were observed including core crushing, core shear, and top skin compression failure. The failure mode map developed based on the experimental finding and analytical prediction indicated that the failure mode is affected by the a/d with the number of glue laminated panels.

Two gap superconductivity in Ba{sub 0.55}K{sub 0.45}Fe{sub 2}As{sub 2} single crystals studied by the directional point-contact Andreev reflection spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Szabo, P.; Pribulova, Z. [Centre of Low Temperature Physics, IEP Slovak Academy of Sciences and P.J.Safarik University, Watsonova 47, SK-04001 Kosice (Slovakia); Pristas, G.; Bud' ko, S.L.; Canfield, P.C. [Ames Laboratory and Iowa State University, Ames, IA 50011 (United States); Samuely, P., E-mail: samuely@saske.s [Centre of Low Temperature Physics, IEP Slovak Academy of Sciences and P.J.Safarik University, Watsonova 47, SK-04001 Kosice (Slovakia)

2009-10-15

First directional point-contact Andreev reflection spectroscopy on the Ba{sub 0.55}K{sub 0.45}Fe{sub 2}As{sub 2} single crystals is presented. The spectra show significant differences when measured in the ab plane in comparison with those measured in the c direction. In the latter case no traces of superconducting energy gap could be found, just a reduced point-contact conductance persisting up to about 100 K and indicating reduced density of states. On the other hand within the ab plane two nodeless superconducting energy gaps DELTA{sub S}approx2-5 meV and DELTA{sub L}approx9-11 meV are detected.

Single-Chain Folding of Synthetic Polymers: A Critical Update.

Science.gov (United States)

Altintas, Ozcan; Barner-Kowollik, Christopher

2015-11-23

The current contribution serves as a critical update to a previous feature article from us (Macromol. Rapid Commun. 2012, 33, 958-971), and highlights the latest advances in the preparation of single chain polymeric nanoparticles and initial-yet promising-attempts towards mimicking the structure of natural biomacromolecules via single-chain folding of well-defined linear polymers via so-called single chain selective point folding and repeat unit folding. The contribution covers selected examples from the literature published up to ca. September 2015. Our aim is not to provide an exhaustive review but rather highlight a selection of new and exciting examples for single-chain folding based on advanced macromolecular precision chemistry. Initially, the discussion focuses on the synthesis and characterization of single-chain folded structures via selective point folding. The second part of the feature article addresses the folding of well-defined single-chain polymers by means of repeat unit folding. The current state of the art in the field of single-chain folding indicates that repeat unit folding-driven nanoparticle preparation is well-advanced, while initial encouraging steps towards building selective point folding systems have been taken. In addition, a summary of the-in our view-open key questions is provided that may guide future biomimetic design efforts. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A study on density functional theory of the effect of pressure on the formation and migration enthalpies of intrinsic point defects in growing single crystal Si

Science.gov (United States)

Sueoka, Koji; Kamiyama, Eiji; Kariyazaki, Hiroaki

2012-05-01

In 1982, Voronkov presented a model describing point defect behavior during the growth of single crystal Si from a melt and derived an expression to predict if the crystal was vacancy- or self-interstitial-rich. Recently, Vanhellemont claimed that one should take into account the impact of compressive stress introduced by the thermal gradient at the melt/solid interface by considering the hydrostatic pressure dependence of the formation enthalpy of the intrinsic point defects. To evaluate the impact of thermal stress more correctly, the pressure dependence of both the formation enthalpy (Hf) and the migration enthalpy (Hm) of the intrinsic point defects should be taken into account. Furthermore, growing single crystal Si is not under hydrostatic pressure but almost free of external pressure (generally in Ar gas under reduced pressure). In the present paper, the dependence of Hf and Hm on the pressure P, or in other words, the pressure dependence of the formation energy (Ef) and the relaxation volume (vf), is quantified by density functional theory calculations. Although a large number of ab initio calculations of the properties of intrinsic point defects have been published during the last years, calculations for Si crystals under pressure are rather scarce. For vacancies V, the reported pressure dependences of HfV are inconsistent. In the present study, by using 216-atom supercells with a sufficient cut-off energy and mesh of k-points, the neutral I and V are found to have nearly constant formation energies EfI and EfV for pressures up to 1 GPa. For the relaxation volume, vfI is almost constant while vfV decreases linearly with increasing pressure P. In case of the hydrostatic pressure Ph, the calculated formation enthalpy HfI and migration enthalpy HmI at the [110] dumbbell site are given by HfI = 3.425 - 0.057 × Ph (eV) and HmI = 0.981 - 0.039 × Ph (eV), respectively, with Ph given in GPa. The calculated HfV and HmV dependencies on Ph given by HfV = 3.543 - 0

FoCuS-point: software for STED fluorescence correlation and time-gated single photon counting

DEFF Research Database (Denmark)

Waithe, Dominic; Clausen, Mathias P; Sezgin, Erdinc

2016-01-01

to be established quickly and efficiently. AVAILABILITY AND IMPLEMENTATION: FoCuS-point is written in python and is available through the github repository: https://github.com/dwaithe/FCS_point_correlator. Furthermore, compiled versions of the code are available as executables which can be run directly in Linux...

A Multi-Point Method Considering the Maximum Power Point Tracking Dynamic Process for Aerodynamic Optimization of Variable-Speed Wind Turbine Blades

Directory of Open Access Journals (Sweden)

Zhiqiang Yang

2016-05-01

Full Text Available Due to the dynamic process of maximum power point tracking (MPPT caused by turbulence and large rotor inertia, variable-speed wind turbines (VSWTs cannot maintain the optimal tip speed ratio (TSR from cut-in wind speed up to the rated speed. Therefore, in order to increase the total captured wind energy, the existing aerodynamic design for VSWT blades, which only focuses on performance improvement at a single TSR, needs to be improved to a multi-point design. In this paper, based on a closed-loop system of VSWTs, including turbulent wind, rotor, drive train and MPPT controller, the distribution of operational TSR and its description based on inflow wind energy are investigated. Moreover, a multi-point method considering the MPPT dynamic process for the aerodynamic optimization of VSWT blades is proposed. In the proposed method, the distribution of operational TSR is obtained through a dynamic simulation of the closed-loop system under a specific turbulent wind, and accordingly the multiple design TSRs and the corresponding weighting coefficients in the objective function are determined. Finally, using the blade of a National Renewable Energy Laboratory (NREL 1.5 MW wind turbine as the baseline, the proposed method is compared with the conventional single-point optimization method using the commercial software Bladed. Simulation results verify the effectiveness of the proposed method.

Dose point kernels for beta-emitting radioisotopes

International Nuclear Information System (INIS)

Prestwich, W.V.; Chan, L.B.; Kwok, C.S.; Wilson, B.

1986-01-01

Knowledge of the dose point kernel corresponding to a specific radionuclide is required to calculate the spatial dose distribution produced in a homogeneous medium by a distributed source. Dose point kernels for commonly used radionuclides have been calculated previously using as a basis monoenergetic dose point kernels derived by numerical integration of a model transport equation. The treatment neglects fluctuations in energy deposition, an effect which has been later incorporated in dose point kernels calculated using Monte Carlo methods. This work describes new calculations of dose point kernels using the Monte Carlo results as a basis. An analytic representation of the monoenergetic dose point kernels has been developed. This provides a convenient method both for calculating the dose point kernel associated with a given beta spectrum and for incorporating the effect of internal conversion. An algebraic expression for allowed beta spectra has been accomplished through an extension of the Bethe-Bacher approximation, and tested against the exact expression. Simplified expression for first-forbidden shape factors have also been developed. A comparison of the calculated dose point kernel for 32 P with experimental data indicates good agreement with a significant improvement over the earlier results in this respect. An analytic representation of the dose point kernel associated with the spectrum of a single beta group has been formulated. 9 references, 16 figures, 3 tables

Exceptional points in open quantum systems

International Nuclear Information System (INIS)

Mueller, Markus; Rotter, Ingrid

2008-01-01

Open quantum systems are embedded in the continuum of scattering wavefunctions and are naturally described by non-Hermitian Hamilton operators. In the complex energy plane, exceptional points appear at which two (or more) eigenvalues of the Hamilton operator coalesce. Although they are a countable set of single points in the complex energy plane and therefore of measure zero, they determine decisively the dynamics of open quantum systems. A powerful method for the description of open quantum systems is the Feshbach projection operator formalism. It is used in the present paper as a basic tool for the study of exceptional points and of the role they play for the dynamics of open quantum systems. Among others, the topological structure of the exceptional points, the rigidity of the phases of the eigenfunctions in their vicinity, the enhancement of observable values due to the reduced phase rigidity and the appearance of phase transitions are considered. The results are compared with existing experimental data on microwave cavities. In the last section, some questions being still unsolved, are considered

Sequence polymorphism in an insect RNA virus field population: A snapshot from a single point in space and time reveals stochastic differences among and within individual hosts

Energy Technology Data Exchange (ETDEWEB)

Stenger, Drake C., E-mail: drake.stenger@ars.usda.gov [USDA, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Ave., Parlier, CA 93648-9757 (United States); Krugner, Rodrigo [USDA, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Ave., Parlier, CA 93648-9757 (United States); Nouri, Shahideh; Ferriol, Inmaculada; Falk, Bryce W. [Department of Plant Pathology, University of California, Davis, CA 95616 (United States); Sisterson, Mark S. [USDA, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Ave., Parlier, CA 93648-9757 (United States)

2016-11-15

Population structure of Homalodisca coagulata Virus-1 (HoCV-1) among and within field-collected insects sampled from a single point in space and time was examined. Polymorphism in complete consensus sequences among single-insect isolates was dominated by synonymous substitutions. The mutant spectrum of the C2 helicase region within each single-insect isolate was unique and dominated by nonsynonymous singletons. Bootstrapping was used to correct the within-isolate nonsynonymous:synonymous arithmetic ratio (N:S) for RT-PCR error, yielding an N:S value ~one log-unit greater than that of consensus sequences. Probability of all possible single-base substitutions for the C2 region predicted N:S values within 95% confidence limits of the corrected within-isolate N:S when the only constraint imposed was viral polymerase error bias for transitions over transversions. These results indicate that bottlenecks coupled with strong negative/purifying selection drive consensus sequences toward neutral sequence space, and that most polymorphism within single-insect isolates is composed of newly-minted mutations sampled prior to selection. -- Highlights: •Sampling protocol minimized differential selection/history among isolates. •Polymorphism among consensus sequences dominated by negative/purifying selection. •Within-isolate N:S ratio corrected for RT-PCR error by bootstrapping. •Within-isolate mutant spectrum dominated by new mutations yet to undergo selection.

Accuracy Constraint Determination in Fixed-Point System Design

Directory of Open Access Journals (Sweden)

Serizel R

2008-01-01

Full Text Available Most of digital signal processing applications are specified and designed with floatingpoint arithmetic but are finally implemented using fixed-point architectures. Thus, the design flow requires a floating-point to fixed-point conversion stage which optimizes the implementation cost under execution time and accuracy constraints. This accuracy constraint is linked to the application performances and the determination of this constraint is one of the key issues of the conversion process. In this paper, a method is proposed to determine the accuracy constraint from the application performance. The fixed-point system is modeled with an infinite precision version of the system and a single noise source located at the system output. Then, an iterative approach for optimizing the fixed-point specification under the application performance constraint is defined and detailed. Finally the efficiency of our approach is demonstrated by experiments on an MP3 encoder.

Topological fixed point theory for singlevalued and multivalued mappings and applications

CERN Document Server

Ben Amar, Afif

2016-01-01

This is a monograph covering topological fixed point theory for several classes of single and multivalued maps. The authors begin by presenting basic notions in locally convex topological vector spaces. Special attention is then devoted to weak compactness, in particular to the theorems of Eberlein–Šmulian, Grothendick and Dunford–Pettis. Leray–Schauder alternatives and eigenvalue problems for decomposable single-valued nonlinear weakly compact operators in Dunford–Pettis spaces are considered, in addition to some variants of Schauder, Krasnoselskii, Sadovskii, and Leray–Schauder type fixed point theorems for different classes of weakly sequentially continuous operators on general Banach spaces. The authors then proceed with an examination of Sadovskii, Furi–Pera, and Krasnoselskii fixed point theorems and nonlinear Leray–Schauder alternatives in the framework of weak topologies and involving multivalued mappings with weakly sequentially closed graph. These results are formulated in terms of ax...

IMAGE TO POINT CLOUD METHOD OF 3D-MODELING

Directory of Open Access Journals (Sweden)

A. G. Chibunichev

2012-07-01

Full Text Available This article describes the method of constructing 3D models of objects (buildings, monuments based on digital images and a point cloud obtained by terrestrial laser scanner. The first step is the automated determination of exterior orientation parameters of digital image. We have to find the corresponding points of the image and point cloud to provide this operation. Before the corresponding points searching quasi image of point cloud is generated. After that SIFT algorithm is applied to quasi image and real image. SIFT algorithm allows to find corresponding points. Exterior orientation parameters of image are calculated from corresponding points. The second step is construction of the vector object model. Vectorization is performed by operator of PC in an interactive mode using single image. Spatial coordinates of the model are calculated automatically by cloud points. In addition, there is automatic edge detection with interactive editing available. Edge detection is performed on point cloud and on image with subsequent identification of correct edges. Experimental studies of the method have demonstrated its efficiency in case of building facade modeling.

Diamond turning of Si and Ge single crystals

Energy Technology Data Exchange (ETDEWEB)

Blake, P.; Scattergood, R.O.

1988-12-01

Single-point diamond turning studies have been completed on Si and Ge crystals. A new process model was developed for diamond turning which is based on a critical depth of cut for plastic flow-to-brittle fracture transitions. This concept, when combined with the actual machining geometry for single-point turning, predicts that {open_quotes}ductile{close_quotes} machining is a combined action of plasticity and fracture. Interrupted cutting experiments also provide a meant to directly measure the critical depth parameter for given machining conditions.

Characteristics of X-point lobe structures in single-null discharges on MAST

Czech Academy of Sciences Publication Activity Database

Harrison, J.R.; Kirk, A.; Chapman, I.T.; Cahyna, Pavel; Liu, Y.; Nardon, E.; Thornton, A.J.

2014-01-01

Roč. 54, č. 6 (2014), 064015-064015 ISSN 0029-5515 R&D Projects: GA ČR GAP205/11/2341 Institutional support: RVO:61389021 Keywords : tokamak * MAST * X-point * resonant magnetic perturbation Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 3.062, year: 2014 http://iopscience.iop.org/0029-5515/54/6/064015/pdf/0029-5515_54_6_064015.pdf

Multigap superconductivity and strong electron-boson coupling in Fe-based superconductors: a point-contact Andreev-reflection study of Ba(Fe(1-x)Co(x))2As2 single crystals.

Science.gov (United States)

Tortello, M; Daghero, D; Ummarino, G A; Stepanov, V A; Jiang, J; Weiss, J D; Hellstrom, E E; Gonnelli, R S

2010-12-03

Directional point-contact Andreev-reflection measurements in Ba(Fe(1-x)Co(x))2As2 single crystals (T(c) = 24.5 K) indicate the presence of two superconducting gaps with no line nodes on the Fermi surface. The point-contact Andreev-reflection spectra also feature additional structures related to the electron-boson interaction, from which the characteristic boson energy Ω(b)(T) is obtained, very similar to the spin-resonance energy observed in neutron scattering experiments. Both the gaps and the additional structures can be reproduced within a three-band s ± Eliashberg model by using an electron-boson spectral function peaked at Ω(0) = 12 meV ≃ Ω(b)(0).

Single-electron charging effects

International Nuclear Information System (INIS)

Ruggiero, S.T.

1991-01-01

The status of our project on single-electron tunneling is, again, excellent. As outlined in our original proposal, a key goal in the development of this project was the demonstration and exploration of the microwave properties of single-electron system. As discussed in this paper such work has to data been carried out. Also as discussed in our previous progress report, the next step in the experimental evolution of the project will be to use lithographically-defined small dots as capacitors as outlined in our proposal. At this point we have made such microdotsdots as will be discussed. We have also continued our work with metal droplets to form single-electron tunnel systems

Estimating envelope thermal characteristics from single point in time thermal images

Science.gov (United States)

Alshatshati, Salahaldin Faraj

Energy efficiency programs implemented nationally in the U.S. by utilities have rendered savings which have cost on average 0.03/kWh. This cost is still well below generation costs. However, as the lowest cost energy efficiency measures are adopted, this the cost effectiveness of further investment declines. Thus there is a need to more effectively find the most opportunities for savings regionally and nationally, so that the greatest cost effectiveness in implementing energy efficiency can be achieved. Integral to this process. are at scale energy audits. However, on-site building energy audits process are expensive, in the range of US1.29/m2-$5.37/m2 and there are an insufficient number of professionals to perform the audits. Energy audits that can be conducted at-scale and at low cost are needed. Research is presented that addresses at community-wide scales characterization of building envelope thermal characteristics via drive-by and fly-over GPS linked thermal imaging. A central question drives this research: Can single point-in-time thermal images be used to infer U-values and thermal capacitances of walls and roofs? Previous efforts to use thermal images to estimate U-values have been limited to rare steady exterior weather conditions. The approaches posed here are based upon the development two models first is a dynamic model of a building envelope component with unknown U-value and thermal capacitance. The weather conditions prior to the thermal image are used as inputs to the model. The model is solved to determine the exterior surface temperature, ultimately predicted the temperature at the thermal measurement time. The model U-value and thermal capacitance are tuned in order to force the error between the predicted surface temperature and the measured surface temperature from thermal imaging to be near zero. This model is developed simply to show that such a model cannot be relied upon to accurately estimate the U-value. The second is a data

In-vivo visualisation of the anatomical structures related to the acupuncture points Dai mai and Shen mai by MRI: A single-case pilot study

International Nuclear Information System (INIS)

Moncayo, Roy; Rudisch, Ansgar; Diemling, Markus; Kremser, Christian

2007-01-01

The concept of acupuncture point localisation in Traditional Chinese Medicine (TCM) is based on millenary practical experience. Modern imaging methods such as PET, MRI and SPECT have been used primary for the investigation of the mechanisms of action of acupuncture. In this pilot single-case study we have evaluated the technical possibilities for in-vivo imaging of the anatomical relations of acupuncture points using state of the art MRI. Preliminary experiments relating to the quality of acupuncture needles under the setting of MRI were done both with stainless steel and gold needles. In a second step, in-vivo imaging was carried out. A licensed acupuncture practitioner (RM) chose two points belonging to the so-called extraordinary vessels. In 2 sequential, separate procedures, he inserted himself gold acupuncture needles using a neutral technique (known as Ping Bu Ping Xie) into the Dai mai and Shen mai points, i.e. gall bladder 26 and bladder 62. Imaging was done on a Siemens Magnetom Avanto MR scanner using a head array and body coil. Mainly T1-weighted imaging sequences, as routinely used for patient exams, were used to obtain multi-slice images. In the preliminary experiments only acupuncture needles made of gold showed enough stability in order to be used for further imaging procedures. Using an onion and a banana as an object, further studies showed that the gold needles produced a void defect that corresponds to the tip of the inserted needle, while at the same time an artefactually increased diameter was observed. The in-vivo experiments showed that the Dai mai point was in relation to the abdominal internal oblique muscle. The Shen mai point artefact showed up close to the longus and brevis peroneal tendons at the fibular malleolus. Side effects related to heating or burning were not observed. Improved anatomical recognition was obtained using 3D-volume rendering techniques. Through an adequate choice of acupuncture material (gold needles) as well as of

Introduction of a point mutation into an HLA class I single-chain trimer induces enhancement of CTL priming and antitumor immunity

Directory of Open Access Journals (Sweden)

Masanori Matsui

2014-01-01

Full Text Available We previously discovered one particular HLA-A*02:01 mutant that enhanced peptide-specific cytotoxic T lymphocyte (CTL recognition in vitro compared to wild-type HLA-A*02:01. This mutant contains a single amino acid substitution from histidine to leucine at position 74 (H74L that is located in the peptide-binding groove. To investigate the effect of the H74L mutation on the in vivo CTL priming, we took advantage of the technology of the HLA class I single-chain trimer (SCT in which three components involving a peptide, β2 microglobulin and the HLA class I heavy chain are joined together via flexible linkers. We generated recombinant adenovirus expressing SCT comprised influenza A matrix protein (FMP-derived peptide, β2 microglobulin and the H74L heavy chain. HLA-A*02:01 transgenic mice were immunized with the adenovirus, and the induction of peptide-specific CTLs and antitumor immunity was investigated. It was clearly shown that the H74L mutation enabled the HLA-A*02:01 SCT molecule to dramatically enhance both in vivo priming of FMP-specific CTLs and protection against a lethal challenge of tumor cells expressing FMP. These data present the first evidence that a simple point mutation in the HLA class I heavy chain of SCT is beneficial for improving CTL-based immunotherapy and prophylaxis to control tumors.

The stress peak at the borehole of point-fitted IGU with undercut anchors

Directory of Open Access Journals (Sweden)

Mike Tibolt

2015-05-01

Full Text Available The highest transparency in glass facades is obtained with point fitted glass units. Point fitted insulating glass units minimize thermal bridging and lead to glass facades with better energy efficiency. Though, insufficient knowledge is present to offer a design method for point fittings in insulating glass. Therefore research has been carried out to extend the existing SLG-design-method (Linear superposition of local and global stress components of Beyer for point fitted single and laminated glass to insulation glass units. This paper presents the first results of this research campaign. Load bearing tests on point fittings in single glazing have been conducted. A finite element model of the point fitting is calibrated by strain comparison. A test campaign for the deviation of a material law for silicone, used as secondary sealant in the edge seal system, is presented. The verified FE-model is implemented in a selected insulation glass unit, and the influence of the edge distance of the point fitting, as well as the edge bond stiffness and geometry on the stress peak at the borehole is investigated. In addition, the size of the so called ‘local area’ is adjusted for insulation glass units.

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.

Ultrasonically Assisted Single Point Diamond Turning of Optical Mold of Tungsten Carbide

Directory of Open Access Journals (Sweden)

Zhanjie Li

2018-02-01

Full Text Available To realize high efficiency, low/no damage and high precision machining of tungsten carbide used for lens mold, a high frequency ultrasonic vibration cutting system was developed at first. Then, tungsten carbide was precisely machined with a polycrystalline diamond (PCD tool assisted by the self-developed high frequency ultrasonic vibration cutting system. Tool wear mechanism was investigated in ductile regime machining of tungsten carbide. The cutter back-off phenomenon in the process was analyzed. The subsequent experimental results of ultra-precision machining with a single crystal diamond tool showed that: under the condition of high frequency ultrasonic vibration cutting, nano-scale surface roughness can be obtained by the diamond tool with smaller tip radius and no defects like those of ground surface were found on the machined surface. Tool wear mechanisms of the single crystal diamond tool are mainly abrasive wear and micro-chipping. To solve the problem, a method of inclined ultrasonic vibration cutting with negative rake angle was put forward according to force analysis, which can further reduce tool wear and roughness of the machined surface. The investigation was important to high efficiency and quality ultra-precision machining of tungsten carbide.

The Point Lepreau Desktop Simulator

International Nuclear Information System (INIS)

MacLean, M.; Hogg, J.; Newman, H.

1997-01-01

The Point Lepreau Desktop Simulator runs plant process modeling software on a 266 MHz single CPU DEC Alpha computer. This same Alpha also runs the plant control computer software on an SSCI 125 emulator. An adjacent Pentium PC runs the simulator's Instructor Facility software, and communicates with the Alpha through an Ethernet. The Point Lepreau Desktop simulator is constructed to be as similar as possible to the Point Lepreau full scope training simulator. This minimizes total maintenance costs and enhances the benefits of the desktop simulator. Both simulators have the same modeling running on a single CPU in the same schedule of calculations. Both simulators have the same Instructor Facility capable of developing and executing the same lesson plans, doing the same monitoring and control of simulations, inserting all the same malfunctions, performing all the same overrides, capable of making and restoring all the same storepoints. Both simulators run the same plant control computer software - the same assembly language control programs as the power plant uses for reactor control, heat transport control, annunciation, etc. This is a higher degree of similarity between a desktop simulator and a full scope training simulator than previously reported for a computer controlled nuclear plant. The large quantity of control room hardware missing from the desktop simulator is replaced by software. The Instructor Facility panel override software of the training simulator provides the means by which devices (switches, controllers, windows, etc.) on the control room panels can be controlled and monitored in the desktop simulator. The CRT of the Alpha provides a mouse operated DCC keyboard mimic for controlling the plant control computer emulation. Two emulated RAMTEK display channels appear as windows for monitoring anything of interest on plant DCC displays, including one channel for annunciation. (author)

Point-source inversion techniques

Science.gov (United States)

Langston, Charles A.; Barker, Jeffrey S.; Pavlin, Gregory B.

1982-11-01

A variety of approaches for obtaining source parameters from waveform data using moment-tensor or dislocation point source models have been investigated and applied to long-period body and surface waves from several earthquakes. Generalized inversion techniques have been applied to data for long-period teleseismic body waves to obtain the orientation, time function and depth of the 1978 Thessaloniki, Greece, event, of the 1971 San Fernando event, and of several events associated with the 1963 induced seismicity sequence at Kariba, Africa. The generalized inversion technique and a systematic grid testing technique have also been used to place meaningful constraints on mechanisms determined from very sparse data sets; a single station with high-quality three-component waveform data is often sufficient to discriminate faulting type (e.g., strike-slip, etc.). Sparse data sets for several recent California earthquakes, for a small regional event associated with the Koyna, India, reservoir, and for several events at the Kariba reservoir have been investigated in this way. Although linearized inversion techniques using the moment-tensor model are often robust, even for sparse data sets, there are instances where the simplifying assumption of a single point source is inadequate to model the data successfully. Numerical experiments utilizing synthetic data and actual data for the 1971 San Fernando earthquake graphically demonstrate that severe problems may be encountered if source finiteness effects are ignored. These techniques are generally applicable to on-line processing of high-quality digital data, but source complexity and inadequacy of the assumed Green's functions are major problems which are yet to be fully addressed.

A New Primary Dew-Point Generator at TUBITAK UME

Science.gov (United States)

Oğuz Aytekin, S.; Karaböce, N.; Heinonen, M.; Sairanen, H.

2018-05-01

An implementation of a new low-range primary humidity generator as a part of an international collaboration between TUBITAK UME and VTT MIKES was initiated as a EURAMET Project Number 1259. The dew-point generator was designed and constructed within the scope of the cooperation between TUBITAK UME and VTT MIKES in order to extend the dew-point temperature measurement capability of Humidity Laboratory of TUBITAK UME down to - 80 °C. The system was thoroughly characterized and validated at TUBITAK UME to support the evidence for dew-point temperature uncertainties. The new generator has a capability of operating in the range of - 80 °C to +10 °C, but at the moment, it was characterized down to - 60 °C. The core of the generator system is a saturator which is fully immersed in a liquid bath. Dry air is supplied to the saturator through a temperature-controlled pre-saturator. The operation of the system is based on the single-pressure generation method with a single pass, i.e., the dew-point temperature is only controlled by the saturator temperature, and the humidity-controlled air is not returned to the system after leaving of the saturator. The metrological performance of the saturator was investigated thoroughly at both National Metrology Institutes. The pre-saturator was also tested using a thermostatic bath at VTT MIKES prior to sending them to TUBITAK UME. This paper describes the principle and design of the generator in detail. The dew-point measurement system and the corresponding uncertainty analysis of the dew-point temperature scale realized with the generator in the range from - 60 °C to 10 °C is also presented.

Relative Critical Points

Directory of Open Access Journals (Sweden)

Debra Lewis

2013-05-01

Full Text Available Relative equilibria of Lagrangian and Hamiltonian systems with symmetry are critical points of appropriate scalar functions parametrized by the Lie algebra (or its dual of the symmetry group. Setting aside the structures – symplectic, Poisson, or variational – generating dynamical systems from such functions highlights the common features of their construction and analysis, and supports the construction of analogous functions in non-Hamiltonian settings. If the symmetry group is nonabelian, the functions are invariant only with respect to the isotropy subgroup of the given parameter value. Replacing the parametrized family of functions with a single function on the product manifold and extending the action using the (coadjoint action on the algebra or its dual yields a fully invariant function. An invariant map can be used to reverse the usual perspective: rather than selecting a parametrized family of functions and finding their critical points, conditions under which functions will be critical on specific orbits, typically distinguished by isotropy class, can be derived. This strategy is illustrated using several well-known mechanical systems – the Lagrange top, the double spherical pendulum, the free rigid body, and the Riemann ellipsoids – and generalizations of these systems.

Accurate dew-point measurement over a wide temperature range using a quartz crystal microbalance dew-point sensor

Science.gov (United States)

Kwon, Su-Yong; Kim, Jong-Chul; Choi, Buyng-Il

2008-11-01

Quartz crystal microbalance (QCM) dew-point sensors are based on frequency measurement, and so have fast response time, high sensitivity and high accuracy. Recently, we have reported that they have the very convenient attribute of being able to distinguish between supercooled dew and frost from a single scan through the resonant frequency of the quartz resonator as a function of the temperature. In addition to these advantages, by using three different types of heat sinks, we have developed a QCM dew/frost-point sensor with a very wide working temperature range (-90 °C to 15 °C). The temperature of the quartz surface can be obtained effectively by measuring the temperature of the quartz crystal holder and using temperature compensation curves (which showed a high level of repeatability and reproducibility). The measured dew/frost points showed very good agreement with reference values and were within ±0.1 °C over the whole temperature range.

Accurate dew-point measurement over a wide temperature range using a quartz crystal microbalance dew-point sensor

International Nuclear Information System (INIS)

Kwon, Su-Yong; Kim, Jong-Chul; Choi, Buyng-Il

2008-01-01

Quartz crystal microbalance (QCM) dew-point sensors are based on frequency measurement, and so have fast response time, high sensitivity and high accuracy. Recently, we have reported that they have the very convenient attribute of being able to distinguish between supercooled dew and frost from a single scan through the resonant frequency of the quartz resonator as a function of the temperature. In addition to these advantages, by using three different types of heat sinks, we have developed a QCM dew/frost-point sensor with a very wide working temperature range (−90 °C to 15 °C). The temperature of the quartz surface can be obtained effectively by measuring the temperature of the quartz crystal holder and using temperature compensation curves (which showed a high level of repeatability and reproducibility). The measured dew/frost points showed very good agreement with reference values and were within ±0.1 °C over the whole temperature range

Gravitational field of massive point particle in general relativity

International Nuclear Information System (INIS)

Fiziev, P.P.

2003-10-01

Using various gauges of the radial coordinate we give a description of the static spherically symmetric space-times with point singularity at the center and vacuum outside the singularity. We show that in general relativity (GR) there exist infinitely many such solutions to the Einstein equations which are physically different and only some of them describe the gravitational field of a single massive point particle. In particular, we show that the widespread Hilbert's form of Schwarzschild solution does not solve the Einstein equations with a massive point particle's stress-energy tensor. Novel normal coordinates for the field and a new physical class of gauges are proposed, in this way achieving a correct description of a point mass source in GR. We also introduce a gravitational mass defect of a point particle and determine the dependence of the solutions on this mass defect. In addition we give invariant characteristics of the physically and geometrically different classes of spherically symmetric static space-times created by one point mass. (author)

ELEVATION ON BOINLING POINT OF COFFE EXTRACT

Directory of Open Access Journals (Sweden)

Telis-Romero J.

2002-01-01

Full Text Available The rise in boiling point of coffee extract was experimentally measured at soluble solids concentrations in the range of 9.2 to 52.4ºBrix and pressures between 5.8 × 10³ and 9.4 × 10(4 Pa (abs.. Different approaches to representing experimental data, including the Dühring's rule, the Antoine equation and empirical models proposed in the literature were tested. In the range of 9.2 to 16.2ºBrix, the rise in boiling point was nearly independent of pressure, varying only with extract concentration. Considerable deviations of this behavior began to occur at concentrations higher than 16.2ºBrix. Experimental data could best be predicted by adjusting an empirical model which consists of a single equation that takes into account the dependence of rise in boiling point on pressure and concentration.

A comparison of groundwater investigation using temporary points versus permanent monitoring wells

International Nuclear Information System (INIS)

Thompson, N.T.

1994-01-01

Groundwater investigation within the environmental industry is most often conducted using permanent monitoring wells. A monitoring well, as the term suggests, is permanent to the extent that it is fixed in place to monitor groundwater quality in its immediate vicinity at any given time over the course of an environmental project. Because monitoring wells are relatively time consuming and expensive to construct, a minimum number of wells is normally installed as part of a single investigation event. The initial information obtained from monitoring wells could also be obtained from temporary groundwater sampling points. Temporary points generally are smaller in diameter than monitoring wells, are installed to provide a one time snap shot of the subsurface, and are removed at the completion of the investigation. Since temporary points are usually easier to install and less expensive than monitoring wells, more temporary points can be installed over a single investigation event and can often reduce or eliminate subsequent assessment(s). A brief discussion of temporary point installation and sampling is offered before considering two case studies within the context of the above advantages to temporary point installation. One case study focuses on vertical delineation of dissolved petroleum hydrocarbons, while the second case study discusses lateral delineation of light nonaqueous phase liquid (LNAPL)

Development of a Multi-Point Microwave Interferometry (MPMI) Method

Energy Technology Data Exchange (ETDEWEB)

Specht, Paul Elliott [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cooper, Marcia A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jilek, Brook Anton [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2015-09-01

A multi-point microwave interferometer (MPMI) concept was developed for non-invasively tracking a shock, reaction, or detonation front in energetic media. Initially, a single-point, heterodyne microwave interferometry capability was established. The design, construction, and verification of the single-point interferometer provided a knowledge base for the creation of the MPMI concept. The MPMI concept uses an electro-optic (EO) crystal to impart a time-varying phase lag onto a laser at the microwave frequency. Polarization optics converts this phase lag into an amplitude modulation, which is analyzed in a heterodyne interfer- ometer to detect Doppler shifts in the microwave frequency. A version of the MPMI was constructed to experimentally measure the frequency of a microwave source through the EO modulation of a laser. The successful extraction of the microwave frequency proved the underlying physical concept of the MPMI design, and highlighted the challenges associated with the longer microwave wavelength. The frequency measurements made with the current equipment contained too much uncertainty for an accurate velocity measurement. Potential alterations to the current construction are presented to improve the quality of the measured signal and enable multiple accurate velocity measurements.

Zero-point length, extra-dimensions and string T-duality

OpenAIRE

Spallucci, Euro; Fontanini, Michele

2005-01-01

In this paper, we are going to put in a single consistent framework apparently unrelated pieces of information, i.e. zero-point length, extra-dimensions, string T-duality. More in details we are going to introduce a modified Kaluza-Klein theory interpolating between (high-energy) string theory and (low-energy) quantum field theory. In our model zero-point length is a four dimensional ``virtual memory'' of compact extra-dimensions length scale. Such a scale turns out to be determined by T-dual...

A comparison of fisheries biological reference points estimated from temperature-specific multi-species and single-species climate-enhanced stock assessment models

Science.gov (United States)

Holsman, Kirstin K.; Ianelli, James; Aydin, Kerim; Punt, André E.; Moffitt, Elizabeth A.

2016-12-01

Multi-species statistical catch at age models (MSCAA) can quantify interacting effects of climate and fisheries harvest on species populations, and evaluate management trade-offs for fisheries that target several species in a food web. We modified an existing MSCAA model to include temperature-specific growth and predation rates and applied the modified model to three fish species, walleye pollock (Gadus chalcogrammus), Pacific cod (Gadus macrocephalus) and arrowtooth flounder (Atheresthes stomias), from the eastern Bering Sea (USA). We fit the model to data from 1979 through 2012, with and without trophic interactions and temperature effects, and use projections to derive single- and multi-species biological reference points (BRP and MBRP, respectively) for fisheries management. The multi-species model achieved a higher over-all goodness of fit to the data (i.e. lower negative log-likelihood) for pollock and Pacific cod. Variability from water temperature typically resulted in 5-15% changes in spawning, survey, and total biomasses, but did not strongly impact recruitment estimates or mortality. Despite this, inclusion of temperature in projections did have a strong effect on BRPs, including recommended yield, which were higher in single-species models for Pacific cod and arrowtooth flounder that included temperature compared to the same models without temperature effects. While the temperature-driven multi-species model resulted in higher yield MBPRs for arrowtooth flounder than the same model without temperature, we did not observe the same patterns in multi-species models for pollock and Pacific cod, where variability between harvest scenarios and predation greatly exceeded temperature-driven variability in yield MBRPs. Annual predation on juvenile pollock (primarily cannibalism) in the multi-species model was 2-5 times the annual harvest of adult fish in the system, thus predation represents a strong control on population dynamics that exceeds temperature

Photonic crystals possessing multiple Weyl points and the experimental observation of robust surface states

Science.gov (United States)

Chen, Wen-Jie; Xiao, Meng; Chan, C. T.

2016-01-01

Weyl points, as monopoles of Berry curvature in momentum space, have captured much attention recently in various branches of physics. Realizing topological materials that exhibit such nodal points is challenging and indeed, Weyl points have been found experimentally in transition metal arsenide and phosphide and gyroid photonic crystal whose structure is complex. If realizing even the simplest type of single Weyl nodes with a topological charge of 1 is difficult, then making a real crystal carrying higher topological charges may seem more challenging. Here we design, and fabricate using planar fabrication technology, a photonic crystal possessing single Weyl points (including type-II nodes) and multiple Weyl points with topological charges of 2 and 3. We characterize this photonic crystal and find nontrivial 2D bulk band gaps for a fixed kz and the associated surface modes. The robustness of these surface states against kz-preserving scattering is experimentally observed for the first time. PMID:27703140

Comparison of plastic strains on AA5052 by single point incremental forming process using digital image processing

International Nuclear Information System (INIS)

Mugendiran, V.; Gnanavelbabu, A.

2017-01-01

In this study, a surface based strain measurement was used to determine the formability of the sheet metal. A strain measurement may employ manual calculation of plastic strains based on the reference circle and the deformed circle. The manual calculation method has a greater margin of error in the practical applications. In this paper, an attempt has been made to compare the formability by implementing three different theoretical approaches: Namely conventional method, least square method and digital based strain measurements. As the sheet metal was formed by a single point incremental process the etched circles get deformed into elliptical shapes approximately, image acquisition has been done before and after forming. The plastic strains of the deformed circle grids are calculated based on the non- deformed reference. The coordinates of the deformed circles are measured by various image processing steps. Finally the strains obtained from the deformed circle are used to plot the forming limit diagram. To evaluate the accuracy of the system, the conventional, least square and digital based method of prediction of the forming limit diagram was compared. Conventional method and least square method have marginal error when compared with digital based processing method. Measurement of strain based on image processing agrees well and can be used to improve the accuracy and to reduce the measurement error in prediction of forming limit diagram.

Evaluation of mixing downstream of tees in duct systems with respect to single point representative air sampling.

Science.gov (United States)

Kim, Taehong; O'Neal, Dennis L; Ortiz, Carlos

2006-09-01

Air duct systems in nuclear facilities must be monitored with continuous sampling in case of an accidental release of airborne radionuclides. The purpose of this work is to identify the air sampling locations where the velocity and contaminant concentrations fall below the 20% coefficient of variation required by the American National Standards Institute/Health Physics Society N13.1-1999. Experiments of velocity and tracer gas concentration were conducted on a generic "T" mixing system which included combinations of three sub ducts, one main duct, and air velocities from 0.5 to 2 m s (100 to 400 fpm). The experimental results suggest that turbulent mixing provides the accepted velocity coefficients of variation after 6 hydraulic diameters downstream of the T-junction. About 95% of the cases achieved coefficients of variation below 10% by 6 hydraulic diameters. However, above a velocity ratio (velocity in the sub duct/velocity in the main duct) of 2, velocity profiles were uniform in a shorter distance downstream of the T-junction as the velocity ratio went up. For the tracer gas concentration, the distance needed for the coefficients of variation to drop 20% decreased with increasing velocity ratio due to the sub duct airflow momentum. The results may apply to other duct systems with similar geometries and, ultimately, be a basis for selecting a proper sampling location under the requirements of single point representative sampling.

Comparison of plastic strains on AA5052 by single point incremental forming process using digital image processing

Energy Technology Data Exchange (ETDEWEB)

Mugendiran, V.; Gnanavelbabu, A. [Anna University, Chennai, Tamilnadu (India)

2017-06-15

In this study, a surface based strain measurement was used to determine the formability of the sheet metal. A strain measurement may employ manual calculation of plastic strains based on the reference circle and the deformed circle. The manual calculation method has a greater margin of error in the practical applications. In this paper, an attempt has been made to compare the formability by implementing three different theoretical approaches: Namely conventional method, least square method and digital based strain measurements. As the sheet metal was formed by a single point incremental process the etched circles get deformed into elliptical shapes approximately, image acquisition has been done before and after forming. The plastic strains of the deformed circle grids are calculated based on the non- deformed reference. The coordinates of the deformed circles are measured by various image processing steps. Finally the strains obtained from the deformed circle are used to plot the forming limit diagram. To evaluate the accuracy of the system, the conventional, least square and digital based method of prediction of the forming limit diagram was compared. Conventional method and least square method have marginal error when compared with digital based processing method. Measurement of strain based on image processing agrees well and can be used to improve the accuracy and to reduce the measurement error in prediction of forming limit diagram.

Single-borehole techniques

International Nuclear Information System (INIS)

Klotz, D.; Moser, H.; Trimborn, P.

1978-01-01

Proceeding on the theoretical considerations and on the experience and practice derived from laboratory and field testing, a system consisting of tracer injection units, detector units, measuring probe units and packers is presented, from which the different borehole probes required can be combined. A couple of examples of recent applications shows the position of the Single-Borehole Techniques with respect to the traditional methods used for the measurement of the ground-water flow. A confrontation of the permeabilities of different aquifers consents, both on the basis of the Single-Borehole Techniques as by pumping experiments, the determination of the reliability of the Point-Dilution-Method. The Point-Dilution-Method is giving information about the vertical and horizontal distribution of the permeabilities in an aquifer. By measuring the vertical current in two karst wells, the tributary horizons of a well have been determined, which gave valuable information for the subsequent well construction. Local leakages could be detected by measuring the vertical flow rate through observation wells arranged along a grout curtain erected on both sides of the retaining barrage of the Keban dam. (orig.) [de

Relationships between Endogenous Plasma Biomarkers of Constitutive Cytochrome P450 3A Activity and Single-Time-Point Oral Midazolam Microdose Phenotype in Healthy Subjects.

Science.gov (United States)

Woolsey, Sarah J; Beaton, Melanie D; Choi, Yun-Hee; Dresser, George K; Gryn, Steven E; Kim, Richard B; Tirona, Rommel G

2016-04-01

Due to high basal interindividual variation in cytochrome P450 3A (CYP3A) activity and susceptibility to drug interactions, there has been interest in the application of efficient probe drug phenotyping strategies, as well as endogenous biomarkers for assessment of in vivo CYP3A activity. The biomarkers 4β-hydroxycholesterol (4βHC) and 6β-hydroxycortisol (6βHCL) are sensitive to CYP3A induction and inhibition. However, their utility for the assessment of constitutive CYP3A activity remains uncertain. We investigated whether endogenous plasma biomarkers (4βHC and 6βHCL) are associated with basal CYP3A metabolic activity in healthy subjects assessed by a convenient single-time-point oral midazolam (MDZ) phenotyping strategy. Plasma 4βHC and 6βHCL metabolic ratios (MRs) were analysed in 51 healthy adult participants. CYP3A activity was determined after administration of an oral MDZ microdose (100 μg). Simple linear and multiple linear regression analyses were performed to assess relationships between MDZ oral clearance, biomarkers and subject covariates. Among study subjects, basal MDZ oral clearance, 4βHC and 6βHCL MRs ranged 6.5-, 10- and 13-fold, respectively. Participant age and alcohol consumption were negatively associated with MDZ oral clearance (p = 0.03 and p = 0.045, respectively), while weight and female sex were associated with lower plasma 4βHC MR (p = 0.0003 and p = 0.032, respectively). Neither 4βHC nor 6βHCL MRs were associated with MDZ oral clearance. Plasma 4βHC and 6βHCL MRs do not relate to MDZ single-time-point metabolic phenotype in the assessment of constitutive CYP3A activity among healthy individuals. © 2015 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

Note: A dual-channel sensor for dew point measurement based on quartz crystal microbalance

Science.gov (United States)

Li, Ning; Meng, Xiaofeng; Nie, Jing

2017-05-01

A new sensor with dual-channel was designed for eliminating the temperature effect on the frequency measurement of the quartz crystal microbalance (QCM) in dew point detection. The sensor uses active temperature control, produces condensation on the surface of QCM, and then detects the dew point. Both the single-channel and the dual-channel methods were conducted based on the device. The measurement error of the single-channel method was less than 0.5 °C at the dew point range of -2 °C-10 °C while the dual-channel was 0.3 °C. The results showed that the dual-channel method was able to eliminate the temperature effect and yield better measurement accuracy.

Design of four-point SENB specimens with stable crack growth

DEFF Research Database (Denmark)

Jørgensen, Jeppe Bjørn; Kildegaard, Casper; Sørensen, Bent F.

2018-01-01

A four-point single-edge-notch-beam (SENB) test specimen loaded in displacement control (fixed grip) is proposed for studying crack deflection at bi-material interfaces. In order to ensure stable crack growth, a novel analytical model of the four-point SENB specimen in fixed grip is derived...... and compared with numerical models. Model results show that the specimen should be short and thick, and the start-crack length should be deep for the crack to propagate stable towards the bi-material interface. Observations from experimental tests of four-point SENB specimens with different start-crack lengths...

Effect of sanhuangwuji powder, anti-rheumatic drugs, and ginger-partitioned acupoint stimulation on the treatment of rheumatoid arthritis with peptic ulcer: a randomized controlled study.

Science.gov (United States)

Liu, Defang; Guo, Mingyang; Hu, Yonghe; Liu, Taihua; Yan, Jiao; Luo, Yong; Yun, Mingdong; Yang, Min; Zhang, Jun; Guo, Linglin

2015-06-01

To observe the efficacy and safety of oral sanhuangwuji powder, anti-rheumatic drugs (ARDs), and ginger-partitioned acupoint stimulation at zusanli (ST 36) on the treatment of rheumatoid arthritis (RA) complicated by peptic ulcer. This prospective randomized controlled study included 180 eligible inpatients and outpatients randomly assigned to an ARD treatment (n.= 60), ginger-partitioned stimulation (n = 60), or combination treatment (n = 60). Patients assigned to the ARD group were given oral celecoxib, methotrexate, and esomeprazole. Patients assigned to the ginger-partitioned stimulation group were given ginger-partitioned acupoint stimulation at zusanli (ST 36) in addition to the ARDs. Patients in the combination treatment group were given oral sanhuangwuji powder, ginger-partitioned acupoint stimulation at susanli (ST 36), and ARDs. All patients were followed up for 2 months to evaluate clinical effects and safety. The study was registered in the World Health Organization database at the General Hospital of Chengdu Military Area Command Chinese People's Liberation Army (ChiCTR-TCC12002824). The combination treatment group had significantly greater improvements in RA symptoms, laboratory outcomes, and gastrointestinal symptom scores, compared with the other groups (P ginger-partitioned stimulation group (χ2= 6.171, P ginger-partitioned acupoint stimulation at zusanli (ST 36), oral sanhuangwuji powder, and ARDs had a better clinical effect for RA with complicated peptic ulcer, compared with ARD treatmentalone or in combination with ginger-partitioned acupoint stimulation.

Single-shot polarimetry imaging of multicore fiber.

Science.gov (United States)

Sivankutty, Siddharth; Andresen, Esben Ravn; Bouwmans, Géraud; Brown, Thomas G; Alonso, Miguel A; Rigneault, Hervé

2016-05-01

We report an experimental test of single-shot polarimetry applied to the problem of real-time monitoring of the output polarization states in each core within a multicore fiber bundle. The technique uses a stress-engineered optical element, together with an analyzer, and provides a point spread function whose shape unambiguously reveals the polarization state of a point source. We implement this technique to monitor, simultaneously and in real time, the output polarization states of up to 180 single-mode fiber cores in both conventional and polarization-maintaining fiber bundles. We demonstrate also that the technique can be used to fully characterize the polarization properties of each individual fiber core, including eigen-polarization states, phase delay, and diattenuation.

Integrating single-point vibrometer and full-field electronic speckle pattern interferometer to evaluate a micro-speaker

Science.gov (United States)

Chang, Wen-Chi; Chen, Yu-Chi; Chien, Chih-Jen; Wang, An-Bang; Lee, Chih-Kung

2011-04-01

A testing system contains an advanced vibrometer/interferometer device (AVID) and a high-speed electronic speckle pattern interferometer (ESPI) was developed. AVID is a laser Doppler vibrometer that can be used to detect single-point linear and angular velocity with DC to 20 MHz bandwidth and with nanometer resolution. In swept frequency mode, frequency response from mHz to MHz of the structure of interest can be measured. The ESPI experimental setup can be used to measure full-field out-of-plane displacement. A 5-1 phase shifting method and a correlation algorithm were used to analyze the phase difference between the reference signal and the speckle signal scattered from the sample surface. In order to show the efficiency and effectiveness of AVID and ESPI, we designed a micro-speaker composed of a plate with fixed boundaries and two piezo-actuators attached to the sides of the plate. The AVID was used to measure the vibration of one of the piezo-actuators and the ESPI was adopted to measure the two-dimensional out-of-plane displacement of the plate. A microphone was used to measure the acoustic response created by the micro-speaker. Driving signal includes random signal, sinusoidal signal, amplitude modulated high-frequency carrier signal, etc. Angular response induced by amplitude modulated high-frequency carrier signal was found to be significantly narrower than the frequency responses created by other types of driving signals. The validity of our newly developed NDE system are detailed by comparing the relationship between the vibration signal of the micro-speaker and the acoustic field generated.

Lost and found: The missing diabolical points in the Fe$_8$ molecular magnet

OpenAIRE

Li, Feifei; Garg, Anupam

2010-01-01

Certain diabolical points in the tunneling spectrum of the single-molecule magnet Fe$_8$ were previously believed to be have been eliminated as a result of a weak fourth-order anisotropy. As shown by Bruno, this is not so, and the points are only displaced in the magnetic field space along the medium anisotropy direction. The previously missing points are numerically located by following the lines of the Berry curvature. The importance of an experimental search for these rediscovered points i...

Development of new photon-counting detectors for single-molecule fluorescence microscopy

Science.gov (United States)

Michalet, X.; Colyer, R. A.; Scalia, G.; Ingargiola, A.; Lin, R.; Millaud, J. E.; Weiss, S.; Siegmund, Oswald H. W.; Tremsin, Anton S.; Vallerga, John V.; Cheng, A.; Levi, M.; Aharoni, D.; Arisaka, K.; Villa, F.; Guerrieri, F.; Panzeri, F.; Rech, I.; Gulinatti, A.; Zappa, F.; Ghioni, M.; Cova, S.

2013-01-01

Two optical configurations are commonly used in single-molecule fluorescence microscopy: point-like excitation and detection to study freely diffusing molecules, and wide field illumination and detection to study surface immobilized or slowly diffusing molecules. Both approaches have common features, but also differ in significant aspects. In particular, they use different detectors, which share some requirements but also have major technical differences. Currently, two types of detectors best fulfil the needs of each approach: single-photon-counting avalanche diodes (SPADs) for point-like detection, and electron-multiplying charge-coupled devices (EMCCDs) for wide field detection. However, there is room for improvements in both cases. The first configuration suffers from low throughput owing to the analysis of data from a single location. The second, on the other hand, is limited to relatively low frame rates and loses the benefit of single-photon-counting approaches. During the past few years, new developments in point-like and wide field detectors have started addressing some of these issues. Here, we describe our recent progresses towards increasing the throughput of single-molecule fluorescence spectroscopy in solution using parallel arrays of SPADs. We also discuss our development of large area photon-counting cameras achieving subnanosecond resolution for fluorescence lifetime imaging applications at the single-molecule level. PMID:23267185

Making SharePoint® Chemically Aware™.

Science.gov (United States)

Tallapragada, Kartik; Chewning, Joseph; Kombo, David; Ludwick, Beverly

2012-01-12

The use of SharePoint® collaboration software for content management has become a critical part of today's drug discovery process. SharePoint 2010 software has laid a foundation which enables researchers to collaborate and search on various contents. The amount of data generated during a transition of a single compound from preclinical discovery to commercialization can easily range in terabytes, thus there is a greater demand of a chemically aware search algorithm that supplements SharePoint which enables researchers to query for information in a more intuitive and effective way. Thus by supplementing SharePoint with Chemically Aware™ features provides a great value to the pharmaceutical and biotech companies and makes drug discovery more efficient. Using several tools we have integrated SharePoint with chemical, compound, and reaction databases, thereby improving the traditional search engine capability and enhancing the user experience. This paper describes the implementation of a Chemically Aware™ system to supplement SharePoint. A Chemically Aware SharePoint (CASP) allows users to tag documents by drawing a structure and associating it with the related content. It also allows the user to search SharePoint software content and internal/external databases by carrying out substructure, similarity, SMILES, and IUPAC name searches. Building on traditional search, CASP takes SharePoint one step further by providing a intuitive GUI to the researchers to base their search on their knowledge of chemistry than textual search. CASP also provides a way to integrate with other systems, for example a researcher can perform a sub-structure search on pdf documents with embedded molecular entities. A Chemically Aware™ system supplementing SharePoint is a step towards making drug discovery process more efficient and also helps researchers to search for information in a more intuitive way. It also helps the researchers to find information which was once difficult to find

Making SharePoint® Chemically Aware™

Directory of Open Access Journals (Sweden)

Tallapragada Kartik

2012-01-01

Full Text Available Abstract Background The use of SharePoint® collaboration software for content management has become a critical part of today's drug discovery process. SharePoint 2010 software has laid a foundation which enables researchers to collaborate and search on various contents. The amount of data generated during a transition of a single compound from preclinical discovery to commercialization can easily range in terabytes, thus there is a greater demand of a chemically aware search algorithm that supplements SharePoint which enables researchers to query for information in a more intuitive and effective way. Thus by supplementing SharePoint with Chemically Aware™ features provides a great value to the pharmaceutical and biotech companies and makes drug discovery more efficient. Using several tools we have integrated SharePoint with chemical, compound, and reaction databases, thereby improving the traditional search engine capability and enhancing the user experience. Results This paper describes the implementation of a Chemically Aware™ system to supplement SharePoint. A Chemically Aware SharePoint (CASP allows users to tag documents by drawing a structure and associating it with the related content. It also allows the user to search SharePoint software content and internal/external databases by carrying out substructure, similarity, SMILES, and IUPAC name searches. Building on traditional search, CASP takes SharePoint one step further by providing a intuitive GUI to the researchers to base their search on their knowledge of chemistry than textual search. CASP also provides a way to integrate with other systems, for example a researcher can perform a sub-structure search on pdf documents with embedded molecular entities. Conclusion A Chemically Aware™ system supplementing SharePoint is a step towards making drug discovery process more efficient and also helps researchers to search for information in a more intuitive way. It also helps the

Point of sale tobacco advertisements in India.

Science.gov (United States)

Chaudhry, S; Chaudhry, S; Chaudhry, K

2007-01-01

The effect of any legislation depends on its implementation. Limited studies indicate that tobacco companies may tend to use such provision for surrogate advertising. The point of sale advertisement provision has been placed in the Indian Tobacco Control legislation. The study was undertaken to assess the Indian scenario in this regard. To assess if there are any violations related to provision of point of tobacco sale advertisements under India's comprehensive tobacco Control legislation in different parts of India. Boards over various shops showing advertisements of tobacco products were observed in the cities of Delhi, Mumbai, Kolkata, Trivandrum and Jaipur, between September 2005 and March 2006. The point of sale advertisements mushroomed after the implementation of 2004 tobacco control legislation. Tobacco advertisement boards fully satisfying the point of sale provision were practically non-existent. The most common violation of point of sale advertisements was the larger size of the board but with tobacco advertisement equal to the size indicated in the legislation and remaining area often showing a picture. Invariably two boards were placed together to provide the impression of a large single repetitive advertisement. More than two boards was not common. Tobacco advertisement boards were also observed on closed shops/ warehouses, shops not selling tobacco products and on several adjacent shops. The purpose of the point of sale advertisements seems to be surrogate advertisement of tobacco products, mainly cigarettes.

Generation of a statistical shape model with probabilistic point correspondences and the expectation maximization- iterative closest point algorithm

International Nuclear Information System (INIS)

Hufnagel, Heike; Pennec, Xavier; Ayache, Nicholas; Ehrhardt, Jan; Handels, Heinz

2008-01-01

Identification of point correspondences between shapes is required for statistical analysis of organ shapes differences. Since manual identification of landmarks is not a feasible option in 3D, several methods were developed to automatically find one-to-one correspondences on shape surfaces. For unstructured point sets, however, one-to-one correspondences do not exist but correspondence probabilities can be determined. A method was developed to compute a statistical shape model based on shapes which are represented by unstructured point sets with arbitrary point numbers. A fundamental problem when computing statistical shape models is the determination of correspondences between the points of the shape observations of the training data set. In the absence of landmarks, exact correspondences can only be determined between continuous surfaces, not between unstructured point sets. To overcome this problem, we introduce correspondence probabilities instead of exact correspondences. The correspondence probabilities are found by aligning the observation shapes with the affine expectation maximization-iterative closest points (EM-ICP) registration algorithm. In a second step, the correspondence probabilities are used as input to compute a mean shape (represented once again by an unstructured point set). Both steps are unified in a single optimization criterion which depe nds on the two parameters 'registration transformation' and 'mean shape'. In a last step, a variability model which best represents the variability in the training data set is computed. Experiments on synthetic data sets and in vivo brain structure data sets (MRI) are then designed to evaluate the performance of our algorithm. The new method was applied to brain MRI data sets, and the estimated point correspondences were compared to a statistical shape model built on exact correspondences. Based on established measures of ''generalization ability'' and ''specificity'', the estimates were very satisfactory

Calibrate the aerial surveying instrument by the limited surface source and the single point source that replace the unlimited surface source

CERN Document Server

Lu Cun Heng

1999-01-01

It is described that the calculating formula and surveying result is found on the basis of the stacking principle of gamma ray and the feature of hexagonal surface source when the limited surface source replaces the unlimited surface source to calibrate the aerial survey instrument on the ground, and that it is found in the light of the exchanged principle of the gamma ray when the single point source replaces the unlimited surface source to calibrate aerial surveying instrument in the air. Meanwhile through the theoretical analysis, the receiving rate of the crystal bottom and side surfaces is calculated when aerial surveying instrument receives gamma ray. The mathematical expression of the gamma ray decaying following height according to the Jinge function regularity is got. According to this regularity, the absorbing coefficient that air absorbs the gamma ray and the detective efficiency coefficient of the crystal is calculated based on the ground and air measuring value of the bottom surface receiving cou...

Fixed-Rate Compressed Floating-Point Arrays.

Science.gov (United States)

Lindstrom, Peter

2014-12-01

Current compression schemes for floating-point data commonly take fixed-precision values and compress them to a variable-length bit stream, complicating memory management and random access. We present a fixed-rate, near-lossless compression scheme that maps small blocks of 4(d) values in d dimensions to a fixed, user-specified number of bits per block, thereby allowing read and write random access to compressed floating-point data at block granularity. Our approach is inspired by fixed-rate texture compression methods widely adopted in graphics hardware, but has been tailored to the high dynamic range and precision demands of scientific applications. Our compressor is based on a new, lifted, orthogonal block transform and embedded coding, allowing each per-block bit stream to be truncated at any point if desired, thus facilitating bit rate selection using a single compression scheme. To avoid compression or decompression upon every data access, we employ a software write-back cache of uncompressed blocks. Our compressor has been designed with computational simplicity and speed in mind to allow for the possibility of a hardware implementation, and uses only a small number of fixed-point arithmetic operations per compressed value. We demonstrate the viability and benefits of lossy compression in several applications, including visualization, quantitative data analysis, and numerical simulation.

Conformal consistency relations for single-field inflation

International Nuclear Information System (INIS)

Creminelli, Paolo; Noreña, Jorge; Simonović, Marko

2012-01-01

We generalize the single-field consistency relations to capture not only the leading term in the squeezed limit — going as 1/q 3 , where q is the small wavevector — but also the subleading one, going as 1/q 2 . This term, for an (n+1)-point function, is fixed in terms of the variation of the n-point function under a special conformal transformation; this parallels the fact that the 1/q 3 term is related with the scale dependence of the n-point function. For the squeezed limit of the 3-point function, this conformal consistency relation implies that there are no terms going as 1/q 2 . We verify that the squeezed limit of the 4-point function is related to the conformal variation of the 3-point function both in the case of canonical slow-roll inflation and in models with reduced speed of sound. In the second case the conformal consistency conditions capture, at the level of observables, the relation among operators induced by the non-linear realization of Lorentz invariance in the Lagrangian. These results mean that, in any single-field model, primordial correlation functions of ζ are endowed with an SO(4,1) symmetry, with dilations and special conformal transformations non-linearly realized by ζ. We also verify the conformal consistency relations for any n-point function in models with a modulation of the inflaton potential, where the scale dependence is not negligible. Finally, we generalize (some of) the consistency relations involving tensors and soft internal momenta

A randomized controlled trial of single point acupuncture in primary dysmenorrhea.

Science.gov (United States)

Liu, Cun-Zhi; Xie, Jie-Ping; Wang, Lin-Peng; Liu, Yu-Qi; Song, Jia-Shan; Chen, Yin-Ying; Shi, Guang-Xia; Zhou, Wei; Gao, Shu-Zhong; Li, Shi-Liang; Xing, Jian-Min; Ma, Liang-Xiao; Wang, Yan-Xia; Zhu, Jiang; Liu, Jian-Ping

2014-06-01

Acupuncture is often used for primary dysmenorrhea. But there is no convincing evidence due to low methodological quality. We aim to assess immediate effect of acupuncture at specific acupoint compared with unrelated acupoint and nonacupoint on primary dysmenorrhea. The Acupuncture Analgesia Effect in Primary Dysmenorrhoea-II is a multicenter controlled trial conducted in six large hospitals of China. Patients who met inclusion criteria were randomly assigned to classic acupoint (N = 167), unrelated acupoint (N = 167), or non-acupoint (N = 167) group on a 1:1:1 basis. They received three sessions with electro-acupuncture at a classic acupoint (Sanyinjiao, SP6), or an unrelated acupoint (Xuanzhong, GB39), or nonacupoint location, respectively. The primary outcome was subjective pain as measured by a 100-mm visual analog scale (VAS). Measurements were obtained at 0, 5, 10, 30, and 60 minutes following the first intervention. In addition, patients scored changes of general complaints using Cox retrospective symptom scales (RSS-Cox) and 7-point verbal rating scale (VRS) during three menstrual cycles. Secondary outcomes included VAS score for average pain, pain total time, additional in-bed time, and proportion of participants using analgesics during three menstrual cycles. Five hundred and one people underwent random assignment. The primary comparison of VAS scores following the first intervention demonstrated that classic acupoint group was more effective both than unrelated acupoint (-4.0 mm, 95% CI -7.1 to -0.9, P = 0.010) and nonacupoint (-4.0 mm, 95% CI -7.0 to -0.9, P = 0.012) groups. However, no significant differences were detected among the three acupuncture groups for RSS-Cox or VRS outcomes. The per-protocol analysis showed similar pattern. No serious adverse events were noted. Specific acupoint acupuncture produced a statistically, but not clinically, significant effect compared with unrelated acupoint and nonacupoint acupuncture in

Interaction of dislocations and point defects in high-purity molybdenum single crystals

International Nuclear Information System (INIS)

Polotskij, I.G.; Benieva, T.Ya.; Golub, T.V.

1975-01-01

The effect of the interstitial atoms distribution on dislocations mobility in extra pure molybdenum is studied. The amplitude relationships of the internal fraction were measured, which makes it possible to record energy dissipation associated with dislocation mobility in conditions of microdeformation. It was established that single crystals of extra pure molybdenum subjected to minor plastic deformation (1%) are characterized by high internal friction, which depends on the degree of crystall purification with regard to interstitial admixtures. Annealing at temperatures of 200 - 500 deg reduces the total level of damping and causes appearance of a sharp amplitude relationship. In this case, the reduction of damping is associated with diffusion of the interstitial atoms towards the dislocation line and its fixation. The irreversible nature of the internal friction amplitude relationship after development of high deformation amplitudes is explained by micro-plastic deformation processes. The amplitude. of deformation, after which the internal friction becomes irreversible, increases with the increase of the annealing temperature. The damping-deformation hysteresis reaches its maximum value after heat treatment at middle tempetatures. With the increase of the annealing temperature, the hysteresis becomes less. Thermal activation causes displacement of the critical amplitude corresponding to production of the delta-epsilon hysteresis to the region of lower values. Using the Pagen, Pare and Goben theory the amplitude-dependent internal friction data have been employed for calculation of the activation volume values which characterize the initial stages of plastic flow in extra pure single crystals of molybdenum

Modification of electronic structure, magnetic structure, and topological phase of bismuthene by point defects

Science.gov (United States)

Kadioglu, Yelda; Kilic, Sevket Berkay; Demirci, Salih; Aktürk, O. Üzengi; Aktürk, Ethem; Ciraci, Salim

2017-12-01

This paper reveals how the electronic structure, magnetic structure, and topological phase of two-dimensional (2D), single-layer structures of bismuth are modified by point defects. We first showed that a free-standing, single-layer, hexagonal structure of bismuth, named h-bismuthene, exhibits nontrivial band topology. We then investigated interactions between single foreign adatoms and bismuthene structures, which comprise stability, bonding, electronic structure, and magnetic structures. Localized states in diverse locations of the band gap and resonant states in band continua of bismuthene are induced upon the adsorption of different adatoms, which modify electronic and magnetic properties. Specific adatoms result in reconstruction around the adsorption site. Single vacancies and divacancies can form readily in bismuthene structures and remain stable at high temperatures. Through rebondings, Stone-Whales-type defects are constructed by divacancies, which transform into a large hole at high temperature. Like adsorbed adatoms, vacancies induce also localized gap states, which can be eliminated through rebondings in divacancies. We also showed that not only the optical and magnetic properties, but also the topological features of pristine h-bismuthene can be modified by point defects. The modification of the topological features depends on the energies of localized states and also on the strength of coupling between point defects.

Motor synergies and the equilibrium-point hypothesis.

Science.gov (United States)

Latash, Mark L

2010-07-01

The article offers a way to unite three recent developments in the field of motor control and coordination: (1) The notion of synergies is introduced based on the principle of motor abundance; (2) The uncontrolled manifold hypothesis is described as offering a computational framework to identify and quantify synergies; and (3) The equilibrium-point hypothesis is described for a single muscle, single joint, and multijoint systems. Merging these concepts into a single coherent scheme requires focusing on control variables rather than performance variables. The principle of minimal final action is formulated as the guiding principle within the referent configuration hypothesis. Motor actions are associated with setting two types of variables by a controller, those that ultimately define average performance patterns and those that define associated synergies. Predictions of the suggested scheme are reviewed, such as the phenomenon of anticipatory synergy adjustments, quick actions without changes in synergies, atypical synergies, and changes in synergies with practice. A few models are briefly reviewed.

Point-to-point microwave power transmission experiment; Maikuroha ni yoru denryoku yuso no kiso kenkyu

Energy Technology Data Exchange (ETDEWEB)

Shimokura, N.; Kirihara, T. [Kansai Electric Power Co. Inc., Osaka (Japan)

1997-09-30

In order to demonstrate the power transmission using microwave and arrange advantages and problems in the wireless power transmission, field tests of point-to-point power transmission were conducted. Microwave frequency of 2.45 GHz was used, which is assigned as the industrial, scientific and medical frequency. The transmission system is composed of generator, director tube, primary radiator, and transmission antenna. The maximum 5 kW of microwave power can be transmitted by combining a 3 m-diameter parabolic antenna and a magnetron. The receiving system is composed of devices called as RECTENNA (rectifying antenna). A large capacity and high efficiency RECTENNA was developed, by which the maximum 2.5 W of input power per single device can be provided. As a result of the experiments, efficiency at the transmission side was over 70%, and RF-DC efficiency at the receiving side was about 51%. At the open-air test site, however, the total efficiency of only 14.8% could be obtained. 8 refs., 12 figs.

Comparison study of human brain response to acupuncture stimulation vs finger tapping task by using real time fMRI

International Nuclear Information System (INIS)

Wang Wei; Zhu Fang; Qi Jianpin; Xia Yeling; Xia Liming; Wang Chengyuan

2002-01-01

Objective: To characterize the central nervous system reaction on acupuncture stimulations of ZUSANLI (S36) and YANGLINGQUAN (G34) by using real time imaging processing (RTIP) functional magnetic resonance imaging. Methods: Functional MR imaging was performed in 17 healthy volunteers with 2 paradigms: acupuncture at acu-points of ZUSANLI (S36 and YANGLINGQUAN (G34) (on the right side) and control stimulations (right finger tapping). Correlation coefficient (CC) of ROI was detected including bilateral sensorimotor area (SMC), pre-motor cortex (PMC), and supplementary motor area (SMA). Only the ROI in which CC ≥ 0.6 and range exceeded 4 pixels was counted as an activated area. Fisher's exact test was performed to analyze the data in SAS software package. Results: In tapping finger task, 16 subjects obtained functional MR images satisfactorily except 1 subjects, and 8 of SMC R , 8 of PMC R , 9 of SMA, 16 of SMC L , and 9 of PMC L were activated. In acupuncture task, 3 subjects were eliminated for gross motion artifacts, there were 6 of SMC R , 10 of PMC R , 8 of SMA, 11 of SMC L , and 10 of PMC L were activated in the rest 14 subjects. Fisher's exact test (2-Tail) (P> 0.05) showed that there was no significant difference in ROI activated by two kinds of stimulus. Conclusion: Real time fMRI was very useful in exploring acupuncture mechanisms. However, its value in practice still requires further study and synthetic appraise integrating clinical acupuncture effect

Multiview 3D sensing and analysis for high quality point cloud reconstruction

Science.gov (United States)

Satnik, Andrej; Izquierdo, Ebroul; Orjesek, Richard

2018-04-01

Multiview 3D reconstruction techniques enable digital reconstruction of 3D objects from the real world by fusing different viewpoints of the same object into a single 3D representation. This process is by no means trivial and the acquisition of high quality point cloud representations of dynamic 3D objects is still an open problem. In this paper, an approach for high fidelity 3D point cloud generation using low cost 3D sensing hardware is presented. The proposed approach runs in an efficient low-cost hardware setting based on several Kinect v2 scanners connected to a single PC. It performs autocalibration and runs in real-time exploiting an efficient composition of several filtering methods including Radius Outlier Removal (ROR), Weighted Median filter (WM) and Weighted Inter-Frame Average filtering (WIFA). The performance of the proposed method has been demonstrated through efficient acquisition of dense 3D point clouds of moving objects.

Two-point resistance of a resistor network embedded on a globe.

Science.gov (United States)

Tan, Zhi-Zhong; Essam, J W; Wu, F Y

2014-07-01

We consider the problem of two-point resistance in an (m-1) × n resistor network embedded on a globe, a geometry topologically equivalent to an m × n cobweb with its boundary collapsed into one single point. We deduce a concise formula for the resistance between any two nodes on the globe using a method of direct summation pioneered by one of us [Z.-Z. Tan, L. Zhou, and J. H. Yang, J. Phys. A: Math. Theor. 46, 195202 (2013)]. This method is contrasted with the Laplacian matrix approach formulated also by one of us [F. Y. Wu, J. Phys. A: Math. Gen. 37, 6653 (2004)], which is difficult to apply to the geometry of a globe. Our analysis gives the result in the form of a single summation.

Acupuncture Therapy for the Treatment of Myelosuppression after Chemotherapy: A Literature Review over the Past 10 Years.

Science.gov (United States)

Fu, Hongwei; Chen, Bo; Hong, Shouhai; Guo, Yi

2015-06-01

The aim of this study is to review current studies on the effect of acupuncture therapy on bone marrow suppression after chemotherapy. The authors of the present paper have searched related literature over the past 10 years at home and abroad, analyzing the features and the effects of acupuncture therapy (including acupuncture, moxibustion, point injection, point application, etc.) for treating myelosuppression after tumor chemotherapy. We also discuss the year of publication, document type, acupuncture therapy, acupoint selection, and adverse effects with figures. We analyzed 159 articles related to acupuncture therapy from 2004 to 2013, and the analysis revealed that point injection was the most frequently used therapy for clinical applications, and that Zusanli (ST36) was the most frequently used acupoint. The results showed that some problems regarding the design method, acupoint selection, and acupuncture intervention measure existed in those research studies. We hope to provide readers with an overall and objective understanding of acupuncture and moxibustion therapy for treating myelosuppression after tumor chemotherapy. Copyright © 2015. Published by Elsevier B.V.

When should we recommend use of dual time-point and delayed time-point imaging techniques in FDG PET?

Energy Technology Data Exchange (ETDEWEB)

Cheng, Gang [Philadelphia VA Medical Center, Department of Radiology, Philadelphia, PA (United States); Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Torigian, Drew A.; Alavi, Abass [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Zhuang, Hongming [Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States)

2013-05-15

FDG PET and PET/CT are now widely used in oncological imaging for tumor characterization, staging, restaging, and response evaluation. However, numerous benign etiologies may cause increased FDG uptake indistinguishable from that of malignancy. Multiple studies have shown that dual time-point imaging (DTPI) of FDG PET may be helpful in differentiating malignancy from benign processes. However, exceptions exist, and some studies have demonstrated significant overlap of FDG uptake patterns between benign and malignant lesions on delayed time-point images. In this review, we summarize our experience and opinions on the value of DTPI and delayed time-point imaging in oncology, with a review of the relevant literature. We believe that the major value of DTPI and delayed time-point imaging is the increased sensitivity due to continued clearance of background activity and continued FDG accumulation in malignant lesions, if the same diagnostic criteria (as in the initial standard single time-point imaging) are used. The specificity of DTPI and delayed time-point imaging depends on multiple factors, including the prevalence of malignancies, the patient population, and the cut-off values (either SUV or retention index) used to define a malignancy. Thus, DTPI and delayed time-point imaging would be more useful if performed for evaluation of lesions in regions with significant background activity clearance over time (such as the liver, the spleen, the mediastinum), and if used in the evaluation of the extent of tumor involvement rather than in the characterization of the nature of any specific lesion. Acute infectious and non-infectious inflammatory lesions remain as the major culprit for diminished diagnostic performance of these approaches (especially in tuberculosis-endemic regions). Tumor heterogeneity may also contribute to inconsistent performance of DTPI. The authors believe that selective use of DTPI and delayed time-point imaging will improve diagnostic accuracy and

Ferrimagnetic Properties of Bond Dilution Mixed Blume-Capel Model with Random Single-Ion Anisotropy

International Nuclear Information System (INIS)

Liu Lei; Yan Shilei

2005-01-01

We study the ferrimagnetic properties of spin 1/2 and spin-1 systems by means of the effective field theory. The system is considered in the framework of bond dilution mixed Blume-Capel model (BCM) with random single-ion anisotropy. The investigation of phase diagrams and magnetization curves indicates the existence of induced magnetic ordering and single or multi-compensation points. Special emphasis is placed on the influence of bond dilution and random single-ion anisotropy on normal or induced magnetic ordering states and single or multi-compensation points. Normal magnetic ordering states take on new phase diagrams with increasing randomness (bond and anisotropy), while anisotropy induced magnetic ordering states are always occurrence no matter whether concentration of anisotropy is large or small. Existence and disappearance of compensation points rely strongly on bond dilution and random single-ion anisotropy. Some results have not been revealed in previous papers and predicted by Neel theory of ferrimagnetism.

Theoretical and experimental study of single particle tracking in extreme conditions: single photon imaging

International Nuclear Information System (INIS)

Cajgfinger, T.

2012-10-01

This manuscript presents my thesis on the high frame rate (500 frames / second) single-photon detector electron-bombarded CMOS (ebCMOS). The first section compares three ultra-sensitive detectors and their methods for improving photon sensitivity: the CMOS low noise (sCMOS), the electron-multiplying CCD (emCCD) with signal multiplication by pixel and the ebCMOS with amplification by applied electric field. The method developed to detect single photon impacts with intra-pixel resolution on the ebCMOS sensor is presented. The second section compares the localization accuracy of these detectors in extreme conditions of very low photon flux (<10 photons/frame). First the theoretical limit is calculated using the Cramer-Rao lower bound for significant parameter sets. An experimental comparison of the detectors is then described. The setup provides one or more point sources controlled in position, signal and background noise. The results allow a comparison of the experimental effectiveness, purity and localization accuracy. The last section describes two experiments with the ebCMOS camera. The first aims at tracking hundreds of quantum dots simultaneously at the Nanoptec center. The second focuses on the swimming of bacteria at the surface at the Joliot Curie Institute. The point sources tracking algorithm using single photons and the Kalman filter implementation developed for these experiments is also described. (author)

[Professor ZHAO Jiping's meridian diagnosis and treatment for primary dysmenorrhea].

Science.gov (United States)

Tan, Cheng; Zhang, Chang; Zhang, Jiajia; Wang, Jun

2016-03-01

For the treatment of primary dysmenorrhea, professor ZHAO Jiping focuses on meridian diagnosis and inspection, and uses pressing methods to locate the response points along the meridian, including acupoints and aishi points. During the stage of attack, it is essential to press along the spleen meridian, mainly Sanyinjiao (SP 6), Diji (SP 8) and Yinlingquan (SP 9); during the stage of remission, it is essential to press along the bladder meridian and stomach meridian, mainly Ganshu (BL 18), Pishu (BL 20), Weishu (BL 21), Shenshu (BL 23) and Zusanli (ST 36). The differences between deficiency syndrome and excess syndrome lead to the different feelings of doctors and patients. Combined with the results of meridian diagnosis and inspection, the aim of treatment can be achieved by different acupuncture methods. Professor ZHAO pays attention to the treatment of accompanied symptoms and timing of treatment, since the relief of accompanied syndromes and selection of timing are keys to relieving patient's pain.

Single Point Incremental Forming to increase material knowledge and production flexibility

Science.gov (United States)

Habraken, A. M.

2016-08-01

Nowadays, manufactured pieces can be divided into two groups: mass production and production of low volume number of parts. Within the second group (prototyping or small batch production), an emerging solution relies on Incremental Sheet Forming or ISF. ISF refers to processes where the plastic deformation occurs by repeated contact with a relatively small tool. More specifically, many publications over the past decade investigate Single Point Incremental Forming (SPIF) where the final shape is determined only by the tool movement. This manufacturing process is characterized by the forming of sheets by means of a CNC controlled generic tool stylus, with the sheets clamped by means of a non-workpiece-specific clamping system and in absence of a partial or a full die. The advantage is no tooling requirements and often enhanced formability, however it poses a challenge in term of process control and accuracy assurance. Note that the most commonly used materials in incremental forming are aluminum and steel alloys however other alloys are also used especially for medical industry applications, such as cobalt and chromium alloys, stainless steel and titanium alloys. Some scientists have applied incremental forming on PVC plates and other on sandwich panels composed of propylene with mild steel and aluminum metallic foams with aluminum sheet metal. Micro incremental forming of thin foils has also been developed. Starting from the scattering of the results of Finite Element (FE) simulations, when one tries to predict the tool force (see SPIF benchmark of 2014 Numisheet conference), we will see how SPIF and even micro SPIF (process applied on thin metallic sheet with a few grains within the thickness) allow investigating the material behavior. This lecture will focus on the identification of constitutive laws, on the SPIF forming mechanisms and formability as well as the failure mechanism. Different hypotheses have been proposed to explain SPIF formability, they will be

Single Point Incremental Forming to increase material knowledge and production flexibility

International Nuclear Information System (INIS)

Habraken, A.M.

2016-01-01

Nowadays, manufactured pieces can be divided into two groups: mass production and production of low volume number of parts. Within the second group (prototyping or small batch production), an emerging solution relies on Incremental Sheet Forming or ISF. ISF refers to processes where the plastic deformation occurs by repeated contact with a relatively small tool. More specifically, many publications over the past decade investigate Single Point Incremental Forming (SPIF) where the final shape is determined only by the tool movement. This manufacturing process is characterized by the forming of sheets by means of a CNC controlled generic tool stylus, with the sheets clamped by means of a non-workpiece-specific clamping system and in absence of a partial or a full die. The advantage is no tooling requirements and often enhanced formability, however it poses a challenge in term of process control and accuracy assurance. Note that the most commonly used materials in incremental forming are aluminum and steel alloys however other alloys are also used especially for medical industry applications, such as cobalt and chromium alloys, stainless steel and titanium alloys. Some scientists have applied incremental forming on PVC plates and other on sandwich panels composed of propylene with mild steel and aluminum metallic foams with aluminum sheet metal. Micro incremental forming of thin foils has also been developed. Starting from the scattering of the results of Finite Element (FE) simulations, when one tries to predict the tool force (see SPIF benchmark of 2014 Numisheet conference), we will see how SPIF and even micro SPIF (process applied on thin metallic sheet with a few grains within the thickness) allow investigating the material behavior. This lecture will focus on the identification of constitutive laws, on the SPIF forming mechanisms and formability as well as the failure mechanism. Different hypotheses have been proposed to explain SPIF formability, they will be

Tapered fiber coupling of single photons emitted by a deterministically positioned single nitrogen vacancy center

Energy Technology Data Exchange (ETDEWEB)

Liebermeister, Lars, E-mail: lars.liebermeister@physik.uni-muenchen.de; Petersen, Fabian; Münchow, Asmus v.; Burchardt, Daniel; Hermelbracht, Juliane; Tashima, Toshiyuki [Fakultät für Physik, Ludwig-Maximilians-Universität München, 80799 München (Germany); Schell, Andreas W.; Benson, Oliver [Institut für Physik, Humboldt-Universität zu Berlin, 12489 Berlin (Germany); Meinhardt, Thomas; Krueger, Anke [Institut für Organische Chemie, Universität Würzburg, 97074 Würzburg (Germany); Wilhelm Conrad Roentgen Research Center for Complex Materials Systems, Universität Würzburg, 97074 Würzburg (Germany); Stiebeiner, Ariane; Rauschenbeutel, Arno [Atominstitut, Technische Universität Wien, 1020 Wien (Austria); Weinfurter, Harald; Weber, Markus, E-mail: markusweber@lmu.de [Fakultät für Physik, Ludwig-Maximilians-Universität München, 80799 München (Germany); Max-Planck-Institut für Quantenoptik, 85748 Garching (Germany)

2014-01-20

A diamond nano-crystal hosting a single nitrogen vacancy (NV) center is optically selected with a confocal scanning microscope and positioned deterministically onto the subwavelength-diameter waist of a tapered optical fiber (TOF) with the help of an atomic force microscope. Based on this nano-manipulation technique, we experimentally demonstrate the evanescent coupling of single fluorescence photons emitted by a single NV-center to the guided mode of the TOF. By comparing photon count rates of the fiber-guided and the free-space modes and with the help of numerical finite-difference time domain simulations, we determine a lower and upper bound for the coupling efficiency of (9.5 ± 0.6)% and (10.4 ± 0.7)%, respectively. Our results are a promising starting point for future integration of single photon sources into photonic quantum networks and applications in quantum information science.

Should the Equilibrium Point Hypothesis (EPH) be Considered a Scientific Theory?

OpenAIRE

Sainburg, Robert L.

2014-01-01

The purpose of this commentary is to discuss factors that limit consideration of the equilibrium point hypothesis as a scientific theory. The EPH describes control of motor neuron threshold through the variable lambda, which corresponds to a unique referent configuration for a muscle, joint, or combination of joints. One of the most compelling features of the equilibrium point hypothesis is the integration of posture and movement control into a single mechanism. While the essential core of th...

DEEP WIDEBAND SINGLE POINTINGS AND MOSAICS IN RADIO INTERFEROMETRY: HOW ACCURATELY DO WE RECONSTRUCT INTENSITIES AND SPECTRAL INDICES OF FAINT SOURCES?

Energy Technology Data Exchange (ETDEWEB)

Rau, U.; Bhatnagar, S.; Owen, F. N., E-mail: rurvashi@nrao.edu [National Radio Astronomy Observatory, Socorro, NM-87801 (United States)

2016-11-01

Many deep wideband wide-field radio interferometric surveys are being designed to accurately measure intensities, spectral indices, and polarization properties of faint source populations. In this paper, we compare various wideband imaging methods to evaluate the accuracy to which intensities and spectral indices of sources close to the confusion limit can be reconstructed. We simulated a wideband single-pointing (C-array, L-Band (1–2 GHz)) and 46-pointing mosaic (D-array, C-Band (4–8 GHz)) JVLA observation using a realistic brightness distribution ranging from 1 μ Jy to 100 mJy and time-, frequency-, polarization-, and direction-dependent instrumental effects. The main results from these comparisons are (a) errors in the reconstructed intensities and spectral indices are larger for weaker sources even in the absence of simulated noise, (b) errors are systematically lower for joint reconstruction methods (such as Multi-Term Multi-Frequency-Synthesis (MT-MFS)) along with A-Projection for accurate primary beam correction, and (c) use of MT-MFS for image reconstruction eliminates Clean-bias (which is present otherwise). Auxiliary tests include solutions for deficiencies of data partitioning methods (e.g., the use of masks to remove clean bias and hybrid methods to remove sidelobes from sources left un-deconvolved), the effect of sources not at pixel centers, and the consequences of various other numerical approximations within software implementations. This paper also demonstrates the level of detail at which such simulations must be done in order to reflect reality, enable one to systematically identify specific reasons for every trend that is observed, and to estimate scientifically defensible imaging performance metrics and the associated computational complexity of the algorithms/analysis procedures.

Value of dual-time-point 18FDG PET-CT imaging on involved-field radiotherapy for hilar and mediastinal metastatic lymph nodes in non-small cell lung cancer

International Nuclear Information System (INIS)

Hu Man; Sun Xindong; Liu Ningbo; Gong Heyi; Fu Zheng; Ma Li; Li Xinke; Xu Xiaoqing; Yu Jinming

2008-01-01

Objective: To discuss the value of dual-time-point 18 FDG PET-CT imaging on involved-field radiotherapy for hilar and mediastinal metastatic lymph nodes in patients with non-small cell lung cancer (NSCLC). Methods: Fifty-four patients with NSCLC were included in this analysis, including 34 men and 20 women with mean age of 59 (34-76) years. Two sequential PET-CT scans given 3-5 days before surgery were standard single-time-point imaging for the whole body and delayed imaging for the thorax. The pathologic data were used as golden standard to determine the difference between the standard single-time-point and dual-time-point PET-CT imaging in the definition of gross target volume (GTV) of involved-field radiotherapy for metastatic lymph nodes. Results: For hilar metastatic lymph nodes, the GTV defined by single-time-point imaging was consistent with pathologic GTV in 21 patients (39%), comparing with 31 patients (57%) by dual-time-point imaging. Using pathologic data as golden standard, GTV alteration defined by single-time-point imaging had statistically significant difference comparing with that defined by dual-time-point imaging( =519.00, P=0.023). For mediastinal metastatic lymph nodes, the GTV defined by single-time-point imaging was consistent with pathologic GTV in 30 patients (56%), comparing with 36 patients (67%) by dual-time-point imaging. Using pathologic data as golden standard, GTV alteration defined by single-time-point imaging had no statistically significant difference comparing with that defined by dual-time-point imaging (u= 397.50, P=0.616). Conclusions: For patients with NSCLC receiving involved-field radiotherapy, GTV definition for hilar and mediastinal metastatic lymph nodes by dual-time-point imaging is more consistent with that by pathologic data. Dual-time-point imaging has a larger value in terms of target delineation for hilar and mediastinal metastatic lymph nodes. (authors)

The correlation function for density perturbations in an expanding universe. III The three-point and predictions of the four-point and higher order correlation functions

Science.gov (United States)

Mcclelland, J.; Silk, J.

1978-01-01

Higher-order correlation functions for the large-scale distribution of galaxies in space are investigated. It is demonstrated that the three-point correlation function observed by Peebles and Groth (1975) is not consistent with a distribution of perturbations that at present are randomly distributed in space. The two-point correlation function is shown to be independent of how the perturbations are distributed spatially, and a model of clustered perturbations is developed which incorporates a nonuniform perturbation distribution and which explains the three-point correlation function. A model with hierarchical perturbations incorporating the same nonuniform distribution is also constructed; it is found that this model also explains the three-point correlation function, but predicts different results for the four-point and higher-order correlation functions than does the model with clustered perturbations. It is suggested that the model of hierarchical perturbations might be explained by the single assumption of having density fluctuations or discrete objects all of the same mass randomly placed at some initial epoch.

Three-point correlation functions of giant magnons with finite size

International Nuclear Information System (INIS)

Ahn, Changrim; Bozhilov, Plamen

2011-01-01

We compute holographic three-point correlation functions or structure constants of a zero-momentum dilaton operator and two (dyonic) giant magnon string states with a finite-size length in the semiclassical approximation. We show that the semiclassical structure constants match exactly with the three-point functions between two su(2) magnon single trace operators with finite size and the Lagrangian in the large 't Hooft coupling constant limit. A special limit J>>√(λ) of our result is compared with the relevant result based on the Luescher corrections.

Proprioceptive Interaction between the Two Arms in a Single-Arm Pointing Task.

Directory of Open Access Journals (Sweden)

Kazuyoshi Kigawa

Full Text Available Proprioceptive signals coming from both arms are used to determine the perceived position of one arm in a two-arm matching task. Here, we examined whether the perceived position of one arm is affected by proprioceptive signals from the other arm in a one-arm pointing task in which participants specified the perceived position of an unseen reference arm with an indicator paddle. Both arms were hidden from the participant's view throughout the study. In Experiment 1, with both arms placed in front of the body, the participants received 70-80 Hz vibration to the elbow flexors of the reference arm (= right arm to induce the illusion of elbow extension. This extension illusion was compared with that when the left arm elbow flexors were vibrated or not. The degree of the vibration-induced extension illusion of the right arm was reduced in the presence of left arm vibration. In Experiment 2, we found that this kinesthetic interaction between the two arms did not occur when the left arm was vibrated in an abducted position. In Experiment 3, the vibration-induced extension illusion of one arm was fully developed when this arm was placed at an abducted position, indicating that the brain receives increased proprioceptive input from a vibrated arm even if the arm was abducted. Our results suggest that proprioceptive interaction between the two arms occurs in a one-arm pointing task when the two arms are aligned with one another. The position sense of one arm measured using a pointer appears to include the influences of incoming information from the other arm when both arms were placed in front of the body and parallel to one another.

Measurement of β-decay end point energy with planar HPGe detector

Science.gov (United States)

Bhattacharjee, T.; Pandit, Deepak; Das, S. K.; Chowdhury, A.; Das, P.; Banerjee, D.; Saha, A.; Mukhopadhyay, S.; Pal, S.; Banerjee, S. R.

2014-12-01

The β - γ coincidence measurement has been performed with a segmented planar Hyper-Pure Germanium (HPGe) detector and a single coaxial HPGe detector to determine the end point energies of nuclear β-decays. The experimental end point energies have been determined for some of the known β-decays in 106Rh →106Pd. The end point energies corresponding to three weak branches in 106Rh →106Pd decay have been measured for the first time. The γ ray and β particle responses for the planar HPGe detector were simulated using the Monte Carlo based code GEANT3. The experimentally obtained β spectra were successfully reproduced with the simulation.

Single Cell Isolation and Analysis

Directory of Open Access Journals (Sweden)

Ping Hu

2016-10-01

Full Text Available Increasing evidence shows that the heterogeneity of individual cells within a genetically identical population can be critical to their peculiar function and fate. Conventional cell based assays mainly analysis the average responses from a population cells, while the difference within individual cells may often be masked. The cell size, RNA transcripts and protein expression level are quite different within individual cells and these variations are key point to answer the problems in cancer, neurobiology, stem cell biology, immunology and developmental biology. To better understand the cell-to-cell variations, the single cell analysis can provide much more detailed information which may be helpful for therapeutic decisions in an increasingly personalized medicine. In this review, we will focus on the recent development in single cell analysis, including methods used in single cell isolation, analysis and some application examples. The review provides the historical background to single cell analysis, discusses limitations, and current and future possibilities in this exciting field of research.

Blinking effect and the use of quantum dots in single molecule spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Rombach-Riegraf, Verena; Oswald, Peter; Bienert, Roland; Petersen, Jan [Albert-Ludwigs-Universitaet Freiburg, Institut fuer Physikalische Chemie, Albertstrasse 23a, 79104 Freiburg (Germany); Domingo, M.P. [Instituto de Carboquimica (CSIC), Miguel Luesma 4, 50018 Zaragoza (Spain); Pardo, Julian [Grupo Apoptosis, Inmunidad y Cancer, Departamento Bioquimica y Biologia Molecular y Celular, Fac. Ciencias, Universidad de Zaragoza, Zaragoza (Spain); Fundacion Aragon I-D (ARAID), Gobierno de Aragon, Zaragoza (Spain); Immune Effector Cells Group, Aragon Health Research Institute (IIS Aragon), Biomedical Research Centre of Aragon (CIBA) Fundacion Aragon I-D - ARAID, Gobierno de Aragon, Zaragoza (Spain); Graeber, P. [Albert-Ludwigs-Universitaet Freiburg, Institut fuer Physikalische Chemie, Albertstrasse 23a, 79104 Freiburg (Germany); Galvez, E.M., E-mail: eva@icb.csic.es [Instituto de Carboquimica (CSIC), Miguel Luesma 4, 50018 Zaragoza (Spain); Immune Effector Cells Group, Aragon Health Research Institute (IIS Aragon), Biomedical Research Centre of Aragon (CIBA) Fundacion Aragon I-D - ARAID, Gobierno de Aragon, Zaragoza (Spain)

2013-01-04

Highlights: Black-Right-Pointing-Pointer It is possible to eliminate the blinking effect of a water-soluble QD. Black-Right-Pointing-Pointer We provide a direct method to study protein function and dynamics at the single level. Black-Right-Pointing-Pointer QD, potent tool for single molecule studies of biochemical and biological processes. -- Abstract: Luminescent semiconductor nanocrystals (quantum dots, QD) have unique photo-physical properties: high photostability, brightness and narrow size-tunable fluorescence spectra. Due to their unique properties, QD-based single molecule studies have become increasingly more popular during the last years. However QDs show a strong blinking effect (random and intermittent light emission), which may limit their use in single molecule fluorescence studies. QD blinking has been widely studied and some hypotheses have been done to explain this effect. Here we summarise what is known about the blinking effect in QDs, how this phenomenon may affect single molecule studies and, on the other hand, how the 'on'/'off' states can be exploited in diverse experimental settings. In addition, we present results showing that site-directed binding of QD to cysteine residues of proteins reduces the blinking effect. This option opens a new possibility of using QDs to study protein-protein interactions and dynamics by single molecule fluorescence without modifying the chemical composition of the solution or the QD surface.

Scanning microscopic four-point conductivity probes

DEFF Research Database (Denmark)

Petersen, Christian Leth; Hansen, Torben Mikael; Bøggild, Peter

2002-01-01

A method for fabricating microscopic four-point probes is presented. The method uses silicon-based microfabrication technology involving only two patterning steps. The last step in the fabrication process is an unmasked deposition of the conducting probe material, and it is thus possible to select...... the conducting material either for a silicon wafer or a single probe unit. Using shadow masking photolithography an electrode spacing (pitch) down to 1.1 mum was obtained, with cantilever separation down to 200 run. Characterisation measurements have shown the microscopic probes to be mechanically very flexible...

A Generic Simulation Approach for the Fast and Accurate Estimation of the Outage Probability of Single Hop and Multihop FSO Links Subject to Generalized Pointing Errors

KAUST Repository

Ben Issaid, Chaouki; Park, Kihong; Alouini, Mohamed-Slim

2017-01-01

When assessing the performance of the free space optical (FSO) communication systems, the outage probability encountered is generally very small, and thereby the use of nave Monte Carlo simulations becomes prohibitively expensive. To estimate these rare event probabilities, we propose in this work an importance sampling approach which is based on the exponential twisting technique to offer fast and accurate results. In fact, we consider a variety of turbulence regimes, and we investigate the outage probability of FSO communication systems, under a generalized pointing error model based on the Beckmann distribution, for both single and multihop scenarios. Selected numerical simulations are presented to show the accuracy and the efficiency of our approach compared to naive Monte Carlo.

A Generic Simulation Approach for the Fast and Accurate Estimation of the Outage Probability of Single Hop and Multihop FSO Links Subject to Generalized Pointing Errors

KAUST Repository

Ben Issaid, Chaouki

2017-07-28

When assessing the performance of the free space optical (FSO) communication systems, the outage probability encountered is generally very small, and thereby the use of nave Monte Carlo simulations becomes prohibitively expensive. To estimate these rare event probabilities, we propose in this work an importance sampling approach which is based on the exponential twisting technique to offer fast and accurate results. In fact, we consider a variety of turbulence regimes, and we investigate the outage probability of FSO communication systems, under a generalized pointing error model based on the Beckmann distribution, for both single and multihop scenarios. Selected numerical simulations are presented to show the accuracy and the efficiency of our approach compared to naive Monte Carlo.

A Doubly Stochastic Change Point Detection Algorithm for Noisy Biological Signals

Directory of Open Access Journals (Sweden)

Nathan Gold

2018-01-01

Full Text Available Experimentally and clinically collected time series data are often contaminated with significant confounding noise, creating short, noisy time series. This noise, due to natural variability and measurement error, poses a challenge to conventional change point detection methods. We propose a novel and robust statistical method for change point detection for noisy biological time sequences. Our method is a significant improvement over traditional change point detection methods, which only examine a potential anomaly at a single time point. In contrast, our method considers all suspected anomaly points and considers the joint probability distribution of the number of change points and the elapsed time between two consecutive anomalies. We validate our method with three simulated time series, a widely accepted benchmark data set, two geological time series, a data set of ECG recordings, and a physiological data set of heart rate variability measurements of fetal sheep model of human labor, comparing it to three existing methods. Our method demonstrates significantly improved performance over the existing point-wise detection methods.

Natural gas treatment: Simultaneous water and hydrocarbon-dew point-control

Energy Technology Data Exchange (ETDEWEB)

Schmidt, T. (Solvay Catalysts GmbH, Hannover (Germany)); Rennemann, D. (Solvay Catalysts GmbH, Hannover (Germany)); Schulz, T. (Solvay Catalysts GmbH, Hannover (Germany))

1993-10-01

Natural gas is a multicomponent mixture of hydrocarbons. The condensation behavior of such mixtures is different from single component systems. The so-called retrograde behavior leads to the observations that saturated vapor (dew point curve) and saturated liquid curve (bubble point curve) are not identical. Between both is a region of saturated phases which even can exist above the critical point. Following this behaviour it is possible that condensation might occur at pressure decrease or at temperature increase, respectively. This phenomenon is undesired in natural gas pipeline networks. Selective removal of higher hydrocarbons by the means of adsorption can change the phase behavior in such a way that condensation does not occur at temperatures and pressures specified for gas distribution. (orig.)

Single-Phase Single-Stage Grid Tied Solar PV System with Active Power Filtering Using Power Balance Theory

Science.gov (United States)

Singh, Yashi; Hussain, Ikhlaq; Singh, Bhim; Mishra, Sukumar

2018-03-01

In this paper, power quality features such as harmonics mitigation, power factor correction with active power filtering are addressed in a single-stage, single-phase solar photovoltaic (PV) grid tied system. The Power Balance Theory (PBT) with perturb and observe based maximum power point tracking algorithm is proposed for the mitigation of power quality problems in a solar PV grid tied system. The solar PV array is interfaced to a single phase AC grid through a Voltage Source Converter (VSC), which provides active power flow from a solar PV array to the grid as well as to the load and it performs harmonics mitigation using PBT based control. The solar PV array power varies with sunlight and due to this, the solar PV grid tied VSC works only 8-10 h per day. At night, when PV power is zero, the VSC works as an active power filter for power quality improvement, and the load active power is delivered by the grid to the load connected at the point of common coupling. This increases the effective utilization of a VSC. The system is modelled and simulated using MATLAB and simulated responses of the system at nonlinear loads and varying environmental conditions are also validated experimentally on a prototype developed in the laboratory.

Single- versus multiple-sample method to measure glomerular filtration rate.

Science.gov (United States)

Delanaye, Pierre; Flamant, Martin; Dubourg, Laurence; Vidal-Petiot, Emmanuelle; Lemoine, Sandrine; Cavalier, Etienne; Schaeffner, Elke; Ebert, Natalie; Pottel, Hans

2018-01-08

There are many different ways to measure glomerular filtration rate (GFR) using various exogenous filtration markers, each having their own strengths and limitations. However, not only the marker, but also the methodology may vary in many ways, including the use of urinary or plasma clearance, and, in the case of plasma clearance, the number of time points used to calculate the area under the concentration-time curve, ranging from only one (Jacobsson method) to eight (or more) blood samples. We collected the results obtained from 5106 plasma clearances (iohexol or 51Cr-ethylenediaminetetraacetic acid (EDTA)) using three to four time points, allowing GFR calculation using the slope-intercept method and the Bröchner-Mortensen correction. For each time point, the Jacobsson formula was applied to obtain the single-sample GFR. We used Bland-Altman plots to determine the accuracy of the Jacobsson method at each time point. The single-sample method showed within 10% concordances with the multiple-sample method of 66.4%, 83.6%, 91.4% and 96.0% at the time points 120, 180, 240 and ≥300 min, respectively. Concordance was poorer at lower GFR levels, and this trend is in parallel with increasing age. Results were similar in males and females. Some discordance was found in the obese subjects. Single-sample GFR is highly concordant with a multiple-sample strategy, except in the low GFR range (<30 mL/min). © The Author 2018. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

An equilibrium point stabilization strategy for the Chen system

International Nuclear Information System (INIS)

Alvarez-Ramirez, Jose; Cevantes, Ilse; Femat, Ricardo

2004-01-01

The aim of this Letter is to address the equilibrium point stabilization problem of the Chen system by employing a simple linear feedback controller derived from time-scaling the dynamics of a single variable. The controller has the advantage of being easy to implement and a rigorous stability proof is provided based on singular perturbation arguments. Results are illustrated via numerical simulations

Role of single-point mutations and deletions on transition temperatures in ideal proteinogenic heteropolymer chains in the gas phase.

Science.gov (United States)

Olivares-Quiroz, L

2016-07-01

A coarse-grained statistical mechanics-based model for ideal heteropolymer proteinogenic chains of non-interacting residues is presented in terms of the size K of the chain and the set of helical propensities [Formula: see text] associated with each residue j along the chain. For this model, we provide an algorithm to compute the degeneracy tensor [Formula: see text] associated with energy level [Formula: see text] where [Formula: see text] is the number of residues with a native contact in a given conformation. From these results, we calculate the equilibrium partition function [Formula: see text] and characteristic temperature [Formula: see text] at which a transition from a low to a high entropy states is observed. The formalism is applied to analyze the effect on characteristic temperatures [Formula: see text] of single-point mutations and deletions of specific amino acids [Formula: see text] along the chain. Two probe systems are considered. First, we address the case of a random heteropolymer of size K and given helical propensities [Formula: see text] on a conformational phase space. Second, we focus our attention to a particular set of neuropentapeptides, [Met-5] and [Leu-5] enkephalins whose thermodynamic stability is a key feature on their coupling to [Formula: see text] and [Formula: see text] receptors and the triggering of biochemical responses.

Measurement of β-decay end point energy with planar HPGe detector

Energy Technology Data Exchange (ETDEWEB)

Bhattacharjee, T., E-mail: btumpa@vecc.gov.in [Physics Group, Variable Energy Cyclotron Centre, Kolkata 700 064 (India); Pandit, Deepak [Physics Group, Variable Energy Cyclotron Centre, Kolkata 700 064 (India); Das, S.K. [RCD-BARC, Variable Energy Cyclotron Centre, Kolkata 700 064 (India); Chowdhury, A.; Das, P. [Physics Group, Variable Energy Cyclotron Centre, Kolkata 700 064 (India); Banerjee, D. [RCD-BARC, Variable Energy Cyclotron Centre, Kolkata 700 064 (India); Saha, A.; Mukhopadhyay, S.; Pal, S.; Banerjee, S.R. [Physics Group, Variable Energy Cyclotron Centre, Kolkata 700 064 (India)

2014-12-11

The β–γ coincidence measurement has been performed with a segmented planar Hyper-Pure Germanium (HPGe) detector and a single coaxial HPGe detector to determine the end point energies of nuclear β-decays. The experimental end point energies have been determined for some of the known β-decays in {sup 106}Rh→{sup 106}Pd. The end point energies corresponding to three weak branches in {sup 106}Rh→{sup 106}Pd decay have been measured for the first time. The γ ray and β particle responses for the planar HPGe detector were simulated using the Monte Carlo based code GEANT3. The experimentally obtained β spectra were successfully reproduced with the simulation.

AUTOMATIC RECOGNITION OF INDOOR NAVIGATION ELEMENTS FROM KINECT POINT CLOUDS

Directory of Open Access Journals (Sweden)

L. Zeng

2017-09-01

Full Text Available This paper realizes automatically the navigating elements defined by indoorGML data standard – door, stairway and wall. The data used is indoor 3D point cloud collected by Kinect v2 launched in 2011 through the means of ORB-SLAM. By contrast, it is cheaper and more convenient than lidar, but the point clouds also have the problem of noise, registration error and large data volume. Hence, we adopt a shape descriptor – histogram of distances between two randomly chosen points, proposed by Osada and merges with other descriptor – in conjunction with random forest classifier to recognize the navigation elements (door, stairway and wall from Kinect point clouds. This research acquires navigation elements and their 3-d location information from each single data frame through segmentation of point clouds, boundary extraction, feature calculation and classification. Finally, this paper utilizes the acquired navigation elements and their information to generate the state data of the indoor navigation module automatically. The experimental results demonstrate a high recognition accuracy of the proposed method.

Automatic Recognition of Indoor Navigation Elements from Kinect Point Clouds

Science.gov (United States)

Zeng, L.; Kang, Z.

2017-09-01

This paper realizes automatically the navigating elements defined by indoorGML data standard - door, stairway and wall. The data used is indoor 3D point cloud collected by Kinect v2 launched in 2011 through the means of ORB-SLAM. By contrast, it is cheaper and more convenient than lidar, but the point clouds also have the problem of noise, registration error and large data volume. Hence, we adopt a shape descriptor - histogram of distances between two randomly chosen points, proposed by Osada and merges with other descriptor - in conjunction with random forest classifier to recognize the navigation elements (door, stairway and wall) from Kinect point clouds. This research acquires navigation elements and their 3-d location information from each single data frame through segmentation of point clouds, boundary extraction, feature calculation and classification. Finally, this paper utilizes the acquired navigation elements and their information to generate the state data of the indoor navigation module automatically. The experimental results demonstrate a high recognition accuracy of the proposed method.

[Observation on therapeutic effect of catgut implantation at acupoints on exercise fatigue and study on the mechanism].

Science.gov (United States)

Chen, Yong-Zhen; Xu, Yi; Yang, Wei-Bin; Lü, Yi-Hao; Fang, Hai-Bo

2008-09-01

To probe into the therapeutic effect of catgut implantation at acupoint on exercise fatigue and to study on the mechanism. Catgut implantation was given at main points Guanyuan (CV 4), Shen shu (BL 23), Mingmen (GV 4), Zusanli (ST 36), Sanyinjiao (SP 6) in 41 players during training for 2 courses. Training-related condition and changes of blood testosterone (T) and hemoglobin (Hb) before and after training were observed. After treatment, sleeping quality, the mental state at the time of getting out of bed in the morning, appetite, training wish, training stamina, training quality, training attention, etc. in the player significantly improved, and blood T and Hb levels significantly increased. Catgut implantation at acupoints can significantly improve exercise fatigue in the player and the mechanism is possibly related with increase of testosterone and hemoglobin levels.

Spike trains in Hodgkin-Huxley model and ISIs of acupuncture manipulations

International Nuclear Information System (INIS)

Wang Jiang; Si Wenjie; Che Yanqiu; Fei Xiangyang

2008-01-01

The Hodgkin-Huxley equations (HH) are parameterized by a number of parameters and shows a variety of qualitatively different behaviors depending on the parameter values. Under stimulation of an external periodic voltage, the ISIs (interspike intervals) of a HH model are investigated in this work, while the frequency of the voltage is taken as the controlling parameter. As well-known, the science of acupuncture and moxibustion is an important component of Traditional Chinese Medicine with a long history. Although there are a number of different acupuncture manipulations, the method for distinguishing them is rarely investigated. With the idea of ISI, we study the electrical signal time series at the spinal dorsal horn produced by three different acupuncture manipulations in Zusanli point and present an effective way to distinguish them

Spike trains in Hodgkin-Huxley model and ISIs of acupuncture manipulations

Energy Technology Data Exchange (ETDEWEB)

Wang Jiang [School of Electrical and Automation Engineering, Tianjin University, Tianjin 300072 (China)], E-mail: jiangwang@tju.edu.cn; Si Wenjie; Che Yanqiu; Fei Xiangyang [School of Electrical and Automation Engineering, Tianjin University, Tianjin 300072 (China)

2008-05-15

The Hodgkin-Huxley equations (HH) are parameterized by a number of parameters and shows a variety of qualitatively different behaviors depending on the parameter values. Under stimulation of an external periodic voltage, the ISIs (interspike intervals) of a HH model are investigated in this work, while the frequency of the voltage is taken as the controlling parameter. As well-known, the science of acupuncture and moxibustion is an important component of Traditional Chinese Medicine with a long history. Although there are a number of different acupuncture manipulations, the method for distinguishing them is rarely investigated. With the idea of ISI, we study the electrical signal time series at the spinal dorsal horn produced by three different acupuncture manipulations in Zusanli point and present an effective way to distinguish them.

Parallel Processing of Big Point Clouds Using Z-Order Partitioning

Science.gov (United States)

Alis, C.; Boehm, J.; Liu, K.

2016-06-01

As laser scanning technology improves and costs are coming down, the amount of point cloud data being generated can be prohibitively difficult and expensive to process on a single machine. This data explosion is not only limited to point cloud data. Voluminous amounts of high-dimensionality and quickly accumulating data, collectively known as Big Data, such as those generated by social media, Internet of Things devices and commercial transactions, are becoming more prevalent as well. New computing paradigms and frameworks are being developed to efficiently handle the processing of Big Data, many of which utilize a compute cluster composed of several commodity grade machines to process chunks of data in parallel. A central concept in many of these frameworks is data locality. By its nature, Big Data is large enough that the entire dataset would not fit on the memory and hard drives of a single node hence replicating the entire dataset to each worker node is impractical. The data must then be partitioned across worker nodes in a manner that minimises data transfer across the network. This is a challenge for point cloud data because there exist different ways to partition data and they may require data transfer. We propose a partitioning based on Z-order which is a form of locality-sensitive hashing. The Z-order or Morton code is computed by dividing each dimension to form a grid then interleaving the binary representation of each dimension. For example, the Z-order code for the grid square with coordinates (x = 1 = 012, y = 3 = 112) is 10112 = 11. The number of points in each partition is controlled by the number of bits per dimension: the more bits, the fewer the points. The number of bits per dimension also controls the level of detail with more bits yielding finer partitioning. We present this partitioning method by implementing it on Apache Spark and investigating how different parameters affect the accuracy and running time of the k nearest neighbour algorithm

Electrons at the monkey saddle: A multicritical Lifshitz point

Science.gov (United States)

Shtyk, A.; Goldstein, G.; Chamon, C.

2017-01-01

We consider two-dimensional interacting electrons at a monkey saddle with dispersion ∝px3-3 pxpy2 . Such a dispersion naturally arises at the multicritical Lifshitz point when three Van Hove saddles merge in an elliptical umbilic elementary catastrophe, which we show can be realized in biased bilayer graphene. A multicritical Lifshitz point of this kind can be identified by its signature Landau level behavior Em∝(Bm ) 3 /2 and related oscillations in thermodynamic and transport properties, such as de Haas-Van Alphen and Shubnikov-de Haas oscillations, whose period triples as the system crosses the singularity. We show, in the case of a single monkey saddle, that the noninteracting electron fixed point is unstable to interactions under the renormalization-group flow, developing either a superconducting instability or non-Fermi-liquid features. Biased bilayer graphene, where there are two non-nested monkey saddles at the K and K' points, exhibits an interplay of competing many-body instabilities, namely, s -wave superconductivity, ferromagnetism, and spin- and charge-density waves.

Electrically continuous graphene from single crystal copper verified by terahertz conductance spectroscopy and micro four-point probe

DEFF Research Database (Denmark)

Buron, Jonas Christian Due; Pizzocchero, Filippo; Jessen, Bjarke Sørensen

2014-01-01

The electrical performance of graphene synthesized by chemical vapor deposition and transferred to insulating surfaces may be compromised by extended defects, including for instance grain boundaries, cracks, wrinkles, and tears. In this study, we experimentally investigate and compare the nano......- and microscale electrical continuity of single layer graphene grown on centimeter-sized single crystal copper with that of previously studied graphene films, grown on commercially available copper foil, after transfer to SiO2 surfaces. The electrical continuity of the graphene films is analyzed using two...... for measurement of the complex conductance response in the frequency range 1-15 terahertz, covering the entire intraband conductance spectrum, and reveals that the conductance response for the graphene grown on single crystalline copper intimately follows the Drude model for a barrier-free conductor. In contrast...

Disruption Neutral Point Experiment on Alcator C-Mod

Science.gov (United States)

Granetz, R. S.; Nakamura, Y.

2000-10-01

Disruptions of single-null elongated plasmas generally result in loss of vertical position control, leading to a current quench occurring at the top or bottom of the machine, with all the attendant problems of halo and eddy currents flowing in divertor structures. On JT-60U, it has been found that if the plasma is operated with its magnetic axis at a particular height, called the neutral point, the initial vertical drift after a thermal quench is significantly slower than usual, and sometimes can even be arrested, thereby avoiding a current quench in the divertor region entirely. In an ongoing collaboration between MIT and JAERI, the neutral point concept is being tested in Alcator C-Mod, which has a significantly higher plasma elongation than JT-60U (1.65 vs 1.3). Calculations using TSC predict a neutral point at z~=+1 cm above the midplane (a=22 cm). The existence of a neutral point has now been experimentally confirmed, albeit at a height of z=+2.7 cm. The plasma has remained vertically stable for up to 9 ms after the disruption thermal quench, which in principle, is long enough for the PF control system to respond, if programmed appropriately. In addition, the physics of the neutral point stability on C-Mod appears to be somewhat different than that on JT-60U.

2-point functions in quantum cosmology

International Nuclear Information System (INIS)

Gielen, Steffen

2012-01-01

We discuss the path-integral formulation of quantum cosmology with a massless scalar field as a sum-over-histories, with particular reference to loop quantum cosmology. Exploiting the analogy with the relativistic particle, we give a complete overview of the possible two-point functions, deriving vertex expansions and composition laws they satisfy. We clarify the tie between definitions using a group averaging procedure and those in a deparametrised framework. We draw some conclusions about the physics of a single quantum universe and multiverse field theories where the role of these sectors and the inner product are reinterpreted.

X Marks the Spot: Creating and Managing a Single Service Point to Improve Customer Service and Maximize Resources

Science.gov (United States)

Venner, Mary Ann; Keshmiripour, Seti

2016-01-01

This article will describe how merging service points in an academic library is an opportunity to improve customer service and utilize staffing resources more efficiently. Combining service points provides libraries with the ability to create a more positive library experience for patrons by minimizing the ping-pong effect for assistance. The…

Quantum phase space points for Wigner functions in finite-dimensional spaces

OpenAIRE

Luis Aina, Alfredo

2004-01-01

We introduce quantum states associated with single phase space points in the Wigner formalism for finite-dimensional spaces. We consider both continuous and discrete Wigner functions. This analysis provides a procedure for a direct practical observation of the Wigner functions for states and transformations without inversion formulas.

Quantum phase space points for Wigner functions in finite-dimensional spaces

International Nuclear Information System (INIS)

Luis, Alfredo

2004-01-01

We introduce quantum states associated with single phase space points in the Wigner formalism for finite-dimensional spaces. We consider both continuous and discrete Wigner functions. This analysis provides a procedure for a direct practical observation of the Wigner functions for states and transformations without inversion formulas

Equilibrium triple point pressure and pressure-temperature phase diagram of polyethylene

NARCIS (Netherlands)

Hikosaka, M.; Tsukijima, K.; Rastogi, S.; Keller, A.

1992-01-01

The equil. triple point and pressure and temp. phase diagrams of polyethylene were obtained by in situ optical microscopic and x-ray observations of the melting temp. of hexagonal and orthorhombic isolated extended-chain single crystals at high pressure. The melting temps. of extended-chain crystals

Shortest path problem on a grid network with unordered intermediate points

Science.gov (United States)

Saw, Veekeong; Rahman, Amirah; Eng Ong, Wen

2017-10-01

We consider a shortest path problem with single cost factor on a grid network with unordered intermediate points. A two stage heuristic algorithm is proposed to find a feasible solution path within a reasonable amount of time. To evaluate the performance of the proposed algorithm, computational experiments are performed on grid maps of varying size and number of intermediate points. Preliminary results for the problem are reported. Numerical comparisons against brute forcing show that the proposed algorithm consistently yields solutions that are within 10% of the optimal solution and uses significantly less computation time.

The tipping point how little things can make a big difference

CERN Document Server

Gladwell, Malcolm

2002-01-01

The tipping point is that magic moment when an idea, trend, or social behavior crosses a threshold, tips, and spreads like wildfire. Just as a single sick person can start an epidemic of the flu, so too can a small but precisely targeted push cause a fashion trend, the popularity of a new product, or a drop in the crime rate. This widely acclaimed bestseller, in which Malcolm Gladwell explores and brilliantly illuminates the tipping point phenomenon, is already changing the way people throughout the world think about selling products and disseminating ideas.

Ifcwall Reconstruction from Unstructured Point Clouds

Science.gov (United States)

Bassier, M.; Klein, R.; Van Genechten, B.; Vergauwen, M.

2018-05-01

The automated reconstruction of Building Information Modeling (BIM) objects from point cloud data is still ongoing research. A key aspect is the creation of accurate wall geometry as it forms the basis for further reconstruction of objects in a BIM. After segmenting and classifying the initial point cloud, the labelled segments are processed and the wall topology is reconstructed. However, the preocedure is challenging due to noise, occlusions and the complexity of the input data.In this work, a method is presented to automatically reconstruct consistent wall geometry from point clouds. More specifically, the use of room information is proposed to aid the wall topology creation. First, a set of partial walls is constructed based on classified planar primitives. Next, the rooms are identified using the retrieved wall information along with the floors and ceilings. The wall topology is computed by the intersection of the partial walls conditioned on the room information. The final wall geometry is defined by creating IfcWallStandardCase objects conform the IFC4 standard. The result is a set of walls according to the as-built conditions of a building. The experiments prove that the used method is a reliable framework for wall reconstruction from unstructured point cloud data. Also, the implementation of room information reduces the rate of false positives for the wall topology. Given the walls, ceilings and floors, 94% of the rooms is correctly identified. A key advantage of the proposed method is that it deals with complex rooms and is not bound to single storeys.

Van Allen Probes Science Gateway: Single-Point Access to Long-Term Radiation Belt Measurements and Space Weather Nowcasting

Science.gov (United States)

Romeo, G.; Barnes, R. J.; Ukhorskiy, A. Y.; Sotirelis, T.; Stephens, G.

2017-12-01

The Science Gateway gives single-point access to over 4.5 years of comprehensive wave and particle measurements from the Van Allen Probes NASA twin-spacecraft mission. The Gateway provides a set of visualization and data analysis tools including: HTML5-based interactive visualization of high-level data products from all instrument teams in the form of: line plots, orbital content plots, dynamical energy spectra, L-shell context plots (including two-spacecraft plotting), FFT spectra of wave data, solar wind and geomagnetic indices data, etc.; download custom multi-instrument CDF data files of selected data products; publication quality plots of digital data; combined orbit predicts for mission planning and coordination including: Van Allen Probes, MMS, THEMIS, Arase (ERG), Cluster, GOES, Geotail, FIREBIRD; magnetic footpoint calculator for coordination with LEO and ground-based assets; real-time computation and processing of empirical magnetic field models - computation of magnetic ephemeris, computation of adiabatic invariants. Van Allen Probes is the first spacecraft mission to provide a nowcast of the radiation environment in the heart of the radiation belts, where the radiation levels are the highest and most dangerous for spacecraft operations. For this purpose, all instruments continuously broadcast a subset of their science data in real time. Van Allen Probes partners with four foreign institutions who operate ground stations that receive the broadcast: Korea (KASI), the Czech republic (CAS), Argentina (CONAE), and Brazil (INPE). The SpWx broadcast is then collected at APL and delivered to the community via the Science Gateway.

Two-point functions in (loop) quantum cosmology

Energy Technology Data Exchange (ETDEWEB)

Calcagni, Gianluca; Oriti, Daniele [Max-Planck-Institute for Gravitational Physics (Albert Einstein Institute), Am Muehlenberg 1, D-14476 Golm (Germany); Gielen, Steffen [Max-Planck-Institute for Gravitational Physics (Albert Einstein Institute), Am Muehlenberg 1, D-14476 Golm (Germany); DAMTP, Centre for Mathematical Sciences, Wilberforce Road, Cambridge CB3 0WA (United Kingdom)

2011-07-01

We discuss the path-integral formulation of quantum cosmology with a massless scalar field as a sum-over-histories of volume transitions, with particular but non-exclusive reference to loop quantum cosmology (LQC). Exploiting the analogy with the relativistic particle, we give a complete overview of the possible two-point functions, pointing out the choices involved in their definitions, deriving their vertex expansions and the composition laws they satisfy. We clarify the origin and relations of different quantities previously defined in the literature, in particular the tie between definitions using a group averaging procedure and those in a deparametrized framework. Finally, we draw some conclusions about the physics of a single quantum universe (where there exist superselection rules on positive- and negative-frequency sectors and different choices of inner product are physically equivalent) and multiverse field theories where the role of these sectors and the inner product are reinterpreted.

Two-point functions in (loop) quantum cosmology

Energy Technology Data Exchange (ETDEWEB)

Calcagni, Gianluca; Gielen, Steffen; Oriti, Daniele, E-mail: calcagni@aei.mpg.de, E-mail: gielen@aei.mpg.de, E-mail: doriti@aei.mpg.de [Max Planck Institute for Gravitational Physics (Albert Einstein Institute), Am Muehlenberg 1, D-14476 Golm (Germany)

2011-06-21

The path-integral formulation of quantum cosmology with a massless scalar field as a sum-over-histories of volume transitions is discussed, with particular but non-exclusive reference to loop quantum cosmology. Exploiting the analogy with the relativistic particle, we give a complete overview of the possible two-point functions, pointing out the choices involved in their definitions, deriving their vertex expansions and the composition laws they satisfy. We clarify the origin and relations of different quantities previously defined in the literature, in particular the tie between definitions using a group averaging procedure and those in a deparametrized framework. Finally, we draw some conclusions about the physics of a single quantum universe (where there exist superselection rules on positive- and negative-frequency sectors and different choices of inner product are physically equivalent) and multiverse field theories where the role of these sectors and the inner product are reinterpreted.

Two-point functions in (loop) quantum cosmology

International Nuclear Information System (INIS)

Calcagni, Gianluca; Gielen, Steffen; Oriti, Daniele

2011-01-01

The path-integral formulation of quantum cosmology with a massless scalar field as a sum-over-histories of volume transitions is discussed, with particular but non-exclusive reference to loop quantum cosmology. Exploiting the analogy with the relativistic particle, we give a complete overview of the possible two-point functions, pointing out the choices involved in their definitions, deriving their vertex expansions and the composition laws they satisfy. We clarify the origin and relations of different quantities previously defined in the literature, in particular the tie between definitions using a group averaging procedure and those in a deparametrized framework. Finally, we draw some conclusions about the physics of a single quantum universe (where there exist superselection rules on positive- and negative-frequency sectors and different choices of inner product are physically equivalent) and multiverse field theories where the role of these sectors and the inner product are reinterpreted.

Fingerprint re-alignment: a solution based on the true fingerprint center point

CSIR Research Space (South Africa)

Msiza, IS

2011-02-01

Full Text Available Solution Based on the True Fingerprint Center Point Ishmael S. Msiza, Brain Leke-Betechuoh, and Tendani Malumedzha Biometrics Research Group ? Information Security CSIR, Modelling & Digital Science Unit Pretoria, Republic of South Africa e... with a pattern that belongs to the Tented Arch (TA) fingerprint class. Fingerprints that belong to the TA class have a single core and a single delta, with the core located almost directly above the delta, as depicted in figure 3 (b). Many singular...

Characterization of point defects in monolayer arsenene

Science.gov (United States)

Liang, Xiongyi; Ng, Siu-Pang; Ding, Ning; Wu, Chi-Man Lawrence

2018-06-01

Topological defects that are inevitably found in 2D materials can dramatically affect their properties. Using density functional theory (DFT) calculations and ab initio molecular dynamics (AIMD) method, the structural, thermodynamic, electronic and magnetic properties of six types of typical point defects in arsenene, i.e. the Stone-Wales defect, single and double vacancies and adatoms, were systemically studied. It was found that these defects were all more easily generated in arsenene with lower formation energies than those with graphene and silicene. Stone-Wales defects can be transformed from pristine arsenene by overcoming a barrier of 2.19 eV and single vacancy defects tend to coalesce into double vacancy defects by diffusion. However, a type of adatom defect does not exhibit kinetic stability at room temperature. In addition, SV defects and another type of adatom defect can remarkably affect the electronic and magnetic properties of arsenene, e.g. they can introduce localized states near the Fermi level, as well as a strongly local magnetic moment due to dangling bond and unpaired electron. Furthermore, the simulated scanning tunneling microscopy (STM) and Raman spectroscopy were computed and the types of point defects can be fully characterized by correlating the STM images and Raman spectra to the defective atomistic structures. The results provide significant insights to the effect of defects in arsenene for potential applications, as well as identifications of two helpful tools (STM and Raman spectroscopy) to distinguish the type of defects in arsenene for future experiments.

Hardening in AlN induced by point defects

International Nuclear Information System (INIS)

Suematsu, H.; Mitchell, T.E.; Iseki, T.; Yano, T.

1991-01-01

Pressureless-sintered AIN was neutron irradiated and the hardness change was examined by Vickers indentation. The hardness was increased by irradiation. When the samples were annealed at high temperature, the hardness gradually decreased. Length was also found to increase and to change in the same way as the hardness. A considerable density of dislocation loops still remained, even after the hardness completely recovered to the value of the unirradiated sample. Thus, it is concluded that the hardening in AIN is caused by isolated point defects and small clusters of point defects, rather than by dislocation loops. Hardness was found to increase in proportion to the length change. If the length change is assumed to be proportional to the point defect density, then the curve could be fitted qualitatively to that predicted by models of solution hardening in metals. Furthermore, the curves for three samples irradiated at different temperatures and fluences are identical. There should be different kinds of defect clusters in samples irradiated at different conditions, e.g., the fraction of single point defects is the highest in the sample irradiated at the lowest temperature. Thus, hardening is insensitive to the kind of defects remaining in the sample and is influenced only by those which contribute to length change

Point source reconstruction principle of linear inverse problems

International Nuclear Information System (INIS)

Terazono, Yasushi; Matani, Ayumu; Fujimaki, Norio; Murata, Tsutomu

2010-01-01

Exact point source reconstruction for underdetermined linear inverse problems with a block-wise structure was studied. In a block-wise problem, elements of a source vector are partitioned into blocks. Accordingly, a leadfield matrix, which represents the forward observation process, is also partitioned into blocks. A point source is a source having only one nonzero block. An example of such a problem is current distribution estimation in electroencephalography and magnetoencephalography, where a source vector represents a vector field and a point source represents a single current dipole. In this study, the block-wise norm, a block-wise extension of the l p -norm, was defined as the family of cost functions of the inverse method. The main result is that a set of three conditions was found to be necessary and sufficient for block-wise norm minimization to ensure exact point source reconstruction for any leadfield matrix that admit such reconstruction. The block-wise norm that satisfies the conditions is the sum of the cost of all the observations of source blocks, or in other words, the block-wisely extended leadfield-weighted l 1 -norm. Additional results are that minimization of such a norm always provides block-wisely sparse solutions and that its solutions form cones in source space

Current Harmonics from Single-Phase Grid-Connected Inverters

DEFF Research Database (Denmark)

Yang, Yongheng; Zhou, Keliang; Blaabjerg, Frede

2016-01-01

Environmental conditions and operational modes may significantly impact the distortion level of the injected current from single-phase grid-connected inverter systems, such as photovoltaic (PV) inverters, which may operate in cloudy days with a maximum power point tracking, in a non-unity power...... factor, or in the low voltage ride through mode with reactive current injection. In this paper, the mechanism of the harmonic current injection from grid-connected single-phase inverter systems is thus explored, and the analysis is conducted on single-phase PV systems. In particular, the analysis...... is focused on the impacts of the power factor and the feed-in grid current level on the quality of the feed-in grid current from single-phase inverters. As a consequence, an internal model principle based high performance current control solution is tailor-made and developed for single-phase grid-connected...

HIV-1 transmitting couples have similar viral load set-points in Rakai, Uganda.

Directory of Open Access Journals (Sweden)

T Déirdre Hollingsworth

2010-05-01

Full Text Available It has been hypothesized that HIV-1 viral load set-point is a surrogate measure of HIV-1 viral virulence, and that it may be subject to natural selection in the human host population. A key test of this hypothesis is whether viral load set-points are correlated between transmitting individuals and those acquiring infection. We retrospectively identified 112 heterosexual HIV-discordant couples enrolled in a cohort in Rakai, Uganda, in which HIV transmission was suspected and viral load set-point was established. In addition, sequence data was available to establish transmission by genetic linkage for 57 of these couples. Sex, age, viral subtype, index partner, and self-reported genital ulcer disease status (GUD were known. Using ANOVA, we estimated the proportion of variance in viral load set-points which was explained by the similarity within couples (the 'couple effect'. Individuals with suspected intra-couple transmission (97 couples had similar viral load set-points (p = 0.054 single factor model, p = 0.0057 adjusted and the couple effect explained 16% of variance in viral loads (23% adjusted. The analysis was repeated for a subset of 29 couples with strong genetic support for transmission. The couple effect was the major determinant of viral load set-point (p = 0.067 single factor, and p = 0.036 adjusted and the size of the effect was 27% (37% adjusted. Individuals within epidemiologically linked couples with genetic support for transmission had similar viral load set-points. The most parsimonious explanation is that this is due to shared characteristics of the transmitted virus, a finding which sheds light on both the role of viral factors in HIV-1 pathogenesis and on the evolution of the virus.

Investigación de la unión soldada entre el vástago y las placas de las cuchillas calzadas // Investigation of the welded joint between plates and tipped single-point lathe tools

Directory of Open Access Journals (Sweden)

M. Jacas Cabrera

2000-01-01

Full Text Available El presente trabajo está dirigido al incremento de los niveles de producción y calidad, específicamente en la línea defabricación de cuchillas calzadas para torno en el centro fabril “Miguel Saavedra” HERRAMIX.En este caso se realizó un análisis para la sustitución de las pastillas de soldar, fabricadas por CIME por nuevastrimetálicas.En el mismo se determinaron los tiempos de calentamiento necesarios para realizar la soldadura, en las máquinas deinducción (TBCHE, así como los valores de resistencia al cizallamiento de los calzos una vez soldados.Palabras claves: Cuchillas de punta, calzos metalo-ceramicos, placas trimetálicas_____________________________________________________________________Abstract:The present work is directed to increase the production and quality levels of tipped single-point lathe tools at “MiguelSaavedra” plant HERRAMIX.This work deals with a study about the substitution of brazing-pads made by CIME for tri-metallic new ones.The induction brazing heating time’s necessaries at induction machines (TBCHE as well as shear-stress values at the tips afterwelding are determined.Key words: tip single point lathe tool, metal ceramic plate, trimetallic pads.

A study of point defect aggregates in #betta#-irradiated LiF single crystals

International Nuclear Information System (INIS)

Frugoli, P.A.; Pimentel, C.A.F.

1982-11-01

Diffuse X-ray scattering near the Bragg Reflection and Bragg profile analaysis have been made in #betta#-irradiated LiF single crystal X-ray diffractometer. An estimate of the half-width of the diffraction patterns was done and preferential alteration in the profile parameters was observed. Clusters with mean parameter sizes from hundreds to thousands of angstroms were observed but each sample has presented a set of average size values. The nature of clusters was found to be dependent on the #betta#-dose: vacancy at low dose (approximately 10 MRad) and interstitial at high dose (approximately 50 MRad). Some process of coalescence at 50 MRad seems to occur. (Author) [pt

Is It Possible to Detect Activated Brown Adipose Tissue in Humans Using Single-Time-Point Infrared Thermography under Thermoneutral Conditions? Impact of BMI and Subcutaneous Adipose Tissue Thickness.

Directory of Open Access Journals (Sweden)

Sergios Gatidis

Full Text Available To evaluate the feasibility to detect activated brown adipose tissue (BAT using single-time-point infrared thermography of the supraclavicular skin region under thermoneutral conditions. To this end, infrared thermography was compared with 18-F-FDG PET, the current reference standard for the detection of activated BAT.120 patients were enrolled in this study. After exclusion of 18 patients, 102 patients (44 female, 58 male, mean age 58±17 years were included for final analysis. All patients underwent a clinically indicated 18F-FDG-PET/CT examination. Immediately prior to tracer injection skin temperatures of the supraclavicular, presternal and jugular regions were measured using spatially resolved infrared thermography at room temperature. The presence of activated BAT was determined in PET by typical FDG uptake within the supraclavicular adipose tissue compartments. Local thickness of supraclavicular subcutaneous adipose tissue (SCAT was measured on CT. Measured skin temperatures were statistically correlated with the presence of activated BAT and anthropometric data.Activated BAT was detected in 9 of 102 patients (8.8%. Local skin temperature of the supraclavicular region was significantly higher in individuals with active BAT compared to individuals without active BAT. However, after statistical correction for the influence of BMI, no predictive value of activated BAT on skin temperature of the supraclavicular region could be observed. Supraclavicular skin temperature was significantly negatively correlated with supraclavicular SCAT thickness.We conclude that supraclavicular SCAT thickness influences supraclavicular skin temperature and thus makes a specific detection of activated BAT using single-time-point thermography difficult. Further studies are necessary to evaluate the possibility of BAT detection using alternative thermographic methods, e.g. dynamic thermography or MR-based thermometry taking into account BMI as a confounding factor.

Automated estimation of leaf distribution for individual trees based on TLS point clouds

Science.gov (United States)

Koma, Zsófia; Rutzinger, Martin; Bremer, Magnus

2017-04-01

Light Detection and Ranging (LiDAR) especially the ground based LiDAR (Terrestrial Laser Scanning - TLS) is an operational used and widely available measurement tool supporting forest inventory updating and research in forest ecology. High resolution point clouds from TLS already represent single leaves which can be used for a more precise estimation of Leaf Area Index (LAI) and for higher accurate biomass estimation. However, currently the methodology for extracting single leafs from the unclassified point clouds for individual trees is still missing. The aim of this study is to present a novel segmentation approach in order to extract single leaves and derive features related to leaf morphology (such as area, slope, length and width) of each single leaf from TLS point cloud data. For the study two exemplary single trees were scanned in leaf-on condition on the university campus of Innsbruck during calm wind conditions. A northern red oak (Quercus rubra) was scanned by a discrete return recording Optech ILRIS-3D TLS scanner and a tulip tree (Liliodendron tulpifera) with Riegl VZ-6000 scanner. During the scanning campaign a reference dataset was measured parallel to scanning. In this case 230 leaves were randomly collected around the lower branches of the tree and photos were taken. The developed workflow steps were the following: in the first step normal vectors and eigenvalues were calculated based on the user specified neighborhood. Then using the direction of the largest eigenvalue outliers i.e. ghost points were removed. After that region growing segmentation based on the curvature and angles between normal vectors was applied on the filtered point cloud. On each segment a RANSAC plane fitting algorithm was applied in order to extract the segment based normal vectors. Using the related features of the calculated segments the stem and branches were labeled as non-leaf and other segments were classified as leaf. The validation of the different segmentation

Wrox SharePoint 2010 SharePoint911 three-pack

CERN Document Server

Klindt, Todd; Mason, Jennifer; Rogers, Laura; Drisgill, Randy; Ross, John; Riemann, Larry; Perran, Amanda; Perran, Shane; Sanford, Jacob J; Stubbs, Paul; Caravajal, Steve

2012-01-01

The Wrox SharePoint 2010 SharePoint911 Three-Pack combines the contents of three full e-books written by the experts from SharePoint911.  That's over 1800 pages of hands-on advice from Todd Klindt, Shane Young, Laura Rogers, Randy Drisgill, Jennifer Mason, John Ross, and Larry Riemann, among others. In Beginning SharePoint 2010: Building Business Solutions with SharePoint (ISBN 978-0-470-61789-2) by Amanda Perran, Shane Perran, Jennifer Mason, and Laura Rogers, readers learn the core concepts, terminology, and features of SharePoint 2010. In Professiona

Liquid oxygen liquid acquisition device bubble point tests with high pressure lox at elevated temperatures

Science.gov (United States)

Jurns, J. M.; Hartwig, J. W.

2012-04-01

When transferring propellant in space, it is most efficient to transfer single phase liquid from a propellant tank to an engine. In earth's gravity field or under acceleration, propellant transfer is fairly simple. However, in low gravity, withdrawing single-phase fluid becomes a challenge. A variety of propellant management devices (PMDs) are used to ensure single-phase flow. One type of PMD, a liquid acquisition device (LAD) takes advantage of capillary flow and surface tension to acquire liquid. The present work reports on testing with liquid oxygen (LOX) at elevated pressures (and thus temperatures) (maximum pressure 1724 kPa and maximum temperature 122 K) as part of NASA's continuing cryogenic LAD development program. These tests evaluate LAD performance for LOX stored in higher pressure vessels that may be used in propellant systems using pressure fed engines. Test data shows a significant drop in LAD bubble point values at higher liquid temperatures, consistent with lower liquid surface tension at those temperatures. Test data also indicates that there are no first order effects of helium solubility in LOX on LAD bubble point prediction. Test results here extend the range of data for LOX fluid conditions, and provide insight into factors affecting predicting LAD bubble point pressures.

Four-point functions with a twist

Energy Technology Data Exchange (ETDEWEB)

Bargheer, Till [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group

2017-01-15

We study the OPE of correlation functions of local operators in planar N=4 super Yang-Mills theory. The considered operators have an explicit spacetime dependence that is defined by twisting the translation generators with certain R-symmetry generators. We restrict to operators that carry a small number of excitations above the twisted BMN vacuum. The OPE limit of the four-point correlator is dominated by internal states with few magnons on top of the vacuum. The twisting directly couples all spacetime dependence of the correlator to these magnons. We analyze the OPE in detail, and single out the extremal states that have to cancel all double-trace contributions.

'Zusanli' (ST.36) on the radiopharmaceutical biodistribution in Wistar ...

Indian Academy of Sciences (India)

... Estado do Rio de Janeiro, Avenida 28 de Setembro, 87, 20551-030, Rio de Janeiro, RJ, Brazil; Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013 Taiwan, Republic of China; Faculty of Medicine and Health Sciences, University of Tunku Abdul Rahman (UTAR), Kuala Lumpur, Malaysia ...

PARALLEL PROCESSING OF BIG POINT CLOUDS USING Z-ORDER-BASED PARTITIONING

Directory of Open Access Journals (Sweden)

C. Alis

2016-06-01

Full Text Available As laser scanning technology improves and costs are coming down, the amount of point cloud data being generated can be prohibitively difficult and expensive to process on a single machine. This data explosion is not only limited to point cloud data. Voluminous amounts of high-dimensionality and quickly accumulating data, collectively known as Big Data, such as those generated by social media, Internet of Things devices and commercial transactions, are becoming more prevalent as well. New computing paradigms and frameworks are being developed to efficiently handle the processing of Big Data, many of which utilize a compute cluster composed of several commodity grade machines to process chunks of data in parallel. A central concept in many of these frameworks is data locality. By its nature, Big Data is large enough that the entire dataset would not fit on the memory and hard drives of a single node hence replicating the entire dataset to each worker node is impractical. The data must then be partitioned across worker nodes in a manner that minimises data transfer across the network. This is a challenge for point cloud data because there exist different ways to partition data and they may require data transfer. We propose a partitioning based on Z-order which is a form of locality-sensitive hashing. The Z-order or Morton code is computed by dividing each dimension to form a grid then interleaving the binary representation of each dimension. For example, the Z-order code for the grid square with coordinates (x = 1 = 012, y = 3 = 112 is 10112 = 11. The number of points in each partition is controlled by the number of bits per dimension: the more bits, the fewer the points. The number of bits per dimension also controls the level of detail with more bits yielding finer partitioning. We present this partitioning method by implementing it on Apache Spark and investigating how different parameters affect the accuracy and running time of the k nearest

Spectral diffusion of quasi localized excitons in single silicon nanocrystals

Energy Technology Data Exchange (ETDEWEB)

Martin, Joerg; Cichos, Frank [Centre for nanostructured Materials and Analytics, Institute of Physics, Chemnitz University of Technology, Reichenhainer Street 70, 09107 Chemnitz (Germany); Borczyskowski, Christian von, E-mail: Borczyskowski@physik.tu-chemnitz.de [Centre for nanostructured Materials and Analytics, Institute of Physics, Chemnitz University of Technology, Reichenhainer Street 70, 09107 Chemnitz (Germany)

2012-08-15

Evolution in time of photoluminescence spectra of SiO{sub x} capped single silicon nanocrystals has been investigated by means of confocal optical spectroscopy at room temperature. Large spectral jumps between subsequent spectra of up to 40 meV have been detected leading to noticeable line broadening and variation in the electron-phonon coupling. Further, a correlation between emission energy and emission intensity has been found and discussed in terms of an intrinsic Stark effect. Anti-correlated variations of the electron-phonon coupling to Si and SiO{sub 2} phonons as a function of photoluminescence energy indicate that the nearly localized excition is to some extent coupled to phonons in the shell covering the silicon nanocrystal. However, coupling is reduced upon increasing Stark effect, while at the same time coupling to phonons of the Si core increases. - Highlights: Black-Right-Pointing-Pointer Single silicon nanocrystals are detected via confocal microscopy. Black-Right-Pointing-Pointer Photoluminescence energies fluctuate strongly in time. Black-Right-Pointing-Pointer Spectral fluctuation is described in the form of spectral diffusion. Black-Right-Pointing-Pointer Dynamic processes are strongly controlled by electron-phonon coupling.

Structure of the magnetopause current layer at the subsolar point

International Nuclear Information System (INIS)

Okuda, H.

1991-12-01

A one-dimensional electromagnetic particle simulation model developed for the magnetopause current layer between the shocked solar wind and the dipole magnetic field at the subsolar point has been extended to include the interplanetary magnetic field (IMF) in the solar wind. Interaction of the solar wind with the vacuum dipole field as well as the dipole field filled with a low density magnetospheric plasma are studied. It is found that the width and the structure of the magnetopause current layer differ markedly depending on the direction of the IMF. When the IMF is pointing southward, the current layer between the solar wind and the dipole field is narrow and the magnetic field has a single ramp structure caused by the reflection of the solar wind at that point. The current layer becomes several times wider and the magnetic field developes a multiple ramp structure when the IMF is northward. This broadening of the current layer is caused by the multiple reflection of the solar wind by the magnetic field. For the northward IMF, the magnetic field does not change its sign across the current layer so that the E x B drift of the solar wind electrons remains the same direction while for the southward IMF, it reverses the sign. This results in a single reflection of the solar wind for the southward IMF and multiple reflections for the northward IMF. When a low density mangetospheric plasma is present in the dipole magnetic field, a small fraction of the solar wind ions are found to penetrate into the dipole magnetic field beyond the reflection point of the solar wind electrons. The width of the ion current layer is of the order of the solar wind ion gyroradius, however, the current associated with the ions remains much smaller than the electron current so long as the density of the magnetospheric plasma is much smaller than the density of the solar wind. Comparisons of our simulation results with the magnetopause crossing near the subsolar point are provided

Towards 4d Virtual City Reconstruction from LIDAR Point Cloud Sequences

Science.gov (United States)

Józsa, O.; Börcs, A.; Benedek, C.

2013-05-01

In this paper we propose a joint approach on virtual city reconstruction and dynamic scene analysis based on point cloud sequences of a single car-mounted Rotating Multi-Beam (RMB) Lidar sensor. The aim of the addressed work is to create 4D spatio-temporal models of large dynamic urban scenes containing various moving and static objects. Standalone RMB Lidar devices have been frequently applied in robot navigation tasks and proved to be efficient in moving object detection and recognition. However, they have not been widely exploited yet for geometric approximation of ground surfaces and building facades due to the sparseness and inhomogeneous density of the individual point cloud scans. In our approach we propose an automatic registration method of the consecutive scans without any additional sensor information such as IMU, and introduce a process for simultaneously extracting reconstructed surfaces, motion information and objects from the registered dense point cloud completed with point time stamp information.

Velocity estimation of an airplane through a single satellite image

Institute of Scientific and Technical Information of China (English)

Zhuxin Zhao; Gongjian Wen; Bingwei Hui; Deren Li

2012-01-01

The motion information of a moving target can be recorded in a single image by a push-broom satellite. A push-broom satellite image is composed of many image lines sensed at different time instants. A method to estimate the velocity of a flying airplane from a single image based on the imagery model of the linear push-broom sensor is proposed. Some key points on the high-resolution image of the plane are chosen to determine the velocity (speed and direction). The performance of the method is tested and verified by experiments using a WorldView-1 image.%The motion information of a moving target can be recorded in a single image by a push-broom satellite.A push-broom satellite image is composed of many image lines sensed at different time instants.A method to estimate the velocity of a flying airplane from a single image based on the imagery model of the linear push-broom sensor is proposed.Some key points on the high-resolution image of the plane are chosen to determine the velocity (speed and direction).The performance of the method is tested and verified by experiments using a WorldView-1 image.

Beginning SharePoint 2010 Administration Windows SharePoint Foundation 2010 and Microsoft SharePoint Server 2010

CERN Document Server

Husman, Göran

2010-01-01

Complete coverage on the latest advances in SharePoint 2010 administration. SharePoint 2010 comprises an abundance of new features, and this book shows you how to take advantage of all SharePoint 2010's many improvements. Written by a four-time SharePoint MVP, Beginning SharePoint 2010 Administration begins with a comparison of SharePoint 2010 compared to the previous version and then examines the differences between WSS 4.0 and MSS 2010. Packed with step-by-step instructions, tips and tricks, and real-world examples, this book dives into the basics of how to install, manage, and administrate

Kernel integration scatter model for parallel beam gamma camera and SPECT point source response

International Nuclear Information System (INIS)

Marinkovic, P.M.

2001-01-01

Scatter correction is a prerequisite for quantitative single photon emission computed tomography (SPECT). In this paper a kernel integration scatter Scatter correction is a prerequisite for quantitative SPECT. In this paper a kernel integration scatter model for parallel beam gamma camera and SPECT point source response based on Klein-Nishina formula is proposed. This method models primary photon distribution as well as first Compton scattering. It also includes a correction for multiple scattering by applying a point isotropic single medium buildup factor for the path segment between the point of scatter an the point of detection. Gamma ray attenuation in the object of imaging, based on known μ-map distribution, is considered too. Intrinsic spatial resolution of the camera is approximated by a simple Gaussian function. Collimator is modeled simply using acceptance angles derived from the physical dimensions of the collimator. Any gamma rays satisfying this angle were passed through the collimator to the crystal. Septal penetration and scatter in the collimator were not included in the model. The method was validated by comparison with Monte Carlo MCNP-4a numerical phantom simulation and excellent results were obtained. The physical phantom experiments, to confirm this method, are planed to be done. (author)

Calibrate the aerial surveying instrument by the limited surface source and the single point source that replace the unlimited surface source

International Nuclear Information System (INIS)

Lu Cunheng

1999-01-01

It is described that the calculating formula and surveying result is found on the basis of the stacking principle of gamma ray and the feature of hexagonal surface source when the limited surface source replaces the unlimited surface source to calibrate the aerial survey instrument on the ground, and that it is found in the light of the exchanged principle of the gamma ray when the single point source replaces the unlimited surface source to calibrate aerial surveying instrument in the air. Meanwhile through the theoretical analysis, the receiving rate of the crystal bottom and side surfaces is calculated when aerial surveying instrument receives gamma ray. The mathematical expression of the gamma ray decaying following height according to the Jinge function regularity is got. According to this regularity, the absorbing coefficient that air absorbs the gamma ray and the detective efficiency coefficient of the crystal is calculated based on the ground and air measuring value of the bottom surface receiving count rate (derived from total receiving count rate of the bottom and side surface). Finally, according to the measuring value, it is proved that imitating the change of total receiving gamma ray exposure rate of the bottom and side surfaces with this regularity in a certain high area is feasible

May 2002 Lidar Point Data of Southern California Coastline: Dana Point to Point La Jolla

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains lidar point data from a strip of Southern California coastline (including water, beach, cliffs, and top of cliffs) from Dana Point to Point La...

September 2002 Lidar Point Data of Southern California Coastline: Dana Point to Point La Jolla

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains lidar point data from a strip of Southern California coastline (including water, beach, cliffs, and top of cliffs) from Dana Point to Point La...

Size-affected single-slip behavior of Rene N5 microcrystals

Energy Technology Data Exchange (ETDEWEB)

Shade, P.A., E-mail: paul.shade@wpafb.af.mil [Department of Materials Science and Engineering, Ohio State University, 477 Watts Hall, 2041 College Road, Columbus, OH 43210 (United States); Air Force Research Laboratory, Materials and Manufacturing Directorate, 2230 10th Street, Wright-Patterson AFB, OH 45433 (United States); Uchic, M.D.; Dimiduk, D.M. [Air Force Research Laboratory, Materials and Manufacturing Directorate, 2230 10th Street, Wright-Patterson AFB, OH 45433 (United States); Viswanathan, G.B.; Wheeler, R. [UES Inc., 4401 Dayton-Xenia Road, Dayton, OH 45432 (United States); Fraser, H.L. [Department of Materials Science and Engineering, Ohio State University, 477 Watts Hall, 2041 College Road, Columbus, OH 43210 (United States)

2012-02-15

Highlights: Black-Right-Pointing-Pointer Microcompression testing was conducted on the single crystal superalloy Rene N5. Black-Right-Pointing-Pointer All microcrystals exhibited size-affected plastic flow. Black-Right-Pointing-Pointer Dendrite core microcrystals were stronger than those from interdendritic regions. - Abstract: Microcompression testing was conducted on the cast single crystal nickel-base superalloy Rene N5. Microcrystals were selectively fabricated from either dendrite core or interdendritic regions. The compression axis was oriented for single-slip deformation and microcrystal diameters ranged from 2.5 to 80 {mu}m. All microcrystals displayed several hallmarks of size-affected plastic flow, including a size-affected and stochastic flow-stress and initial strain hardening rate, as well as an intermittent flow response. The magnitude of size-affected flow-stress scaling behavior was dependent upon the plastic strain level of the flow-stress measurement, with increasing size-dependence for increasing strain levels. TEM analysis demonstrated the activation of multiple slip-systems, despite the microcrystals being oriented for single-slip deformation. Zig-zag slip was also observed in microcrystals that achieved flow stresses of {approx}1300 MPa or higher. For microcrystals fabricated within interdendritic regions the flow-stress values are, on average, lower compared to dendrite core microcrystals. This difference in flow-stress is especially pronounced for microcrystals which are 5 {mu}m in diameter. The microcrystal diameter for which bulk-like properties are estimated to be observed is approximately 350 {mu}m, which is approaching the measured primary dendrite arm spacing for this crystal (430 {mu}m).

Frequency guided methods for demodulation of a single fringe pattern.

Science.gov (United States)

Wang, Haixia; Kemao, Qian

2009-08-17

Phase demodulation from a single fringe pattern is a challenging task but of interest. A frequency-guided regularized phase tracker and a frequency-guided sequential demodulation method with Levenberg-Marquardt optimization are proposed to demodulate a single fringe pattern. Demodulation path guided by the local frequency from the highest to the lowest is applied in both methods. Since critical points have low local frequency values, they are processed last so that the spurious sign problem caused by these points is avoided. These two methods can be considered as alternatives to the effective fringe follower regularized phase tracker. Demodulation results from one computer-simulated and two experimental fringe patterns using the proposed methods will be demonstrated. (c) 2009 Optical Society of America

Prolonged analgesic effect of PLGA-encapsulated bee venom on formalin-induced pain in rats.

Science.gov (United States)

Jeong, Injae; Kim, Beom-Soo; Lee, Hyejung; Lee, Kang-Min; Shim, Insop; Kang, Sung-Keel; Yin, Chang-Shick; Hahm, Dae-Hyun

2009-10-01

To enhance the medicinal activity of bee venom (BV) acupuncture, bee venom was loaded into biodegradable poly(D,L-lactide-co-glycolide) nanoparticles (BV-PLGA-NPs) by a water-in-oil-in-water-emulsion/solvent-evaporation technique. Rat formalin tests were performed after subcutaneous injection of BV-PLGA-NPs to the Zusanli acupuncture point (ST36) at 0.5, 1, 2, 6, 12, 24, and 48 h before plantar injection of 2% formalin. BV-PLGA-NPs treatment showed comparable analgesic activity to typical BV acupuncture during the late phase, compared with saline-treated controls, and the analgesic effect lasted for 12h. PLGA-encapsulation was also effective in alleviating the edema induced by allergens in bee venom. These results indicate that PLGA-encapsulation provided a more prolonged effect of BV acupuncture treatment, while maintaining a comparable therapeutic effect.

The effect of data points per x- to y-axis ratio on visual analysts evaluation of single-case graphs.

Science.gov (United States)

Radley, Keith C; Dart, Evan H; Wright, Sarah J

2018-02-15

Research based on single-case designs (SCD) are frequently utilized in educational settings to evaluate the effect of an intervention on student behavior. Visual analysis is the primary method of evaluation of SCD, despite research noting concerns regarding reliability of the procedure. Recent research suggests that characteristics of the graphic display may contribute to poor reliability and overestimation of intervention effects. This study investigated the effect of increasing or decreasing the data points per x- to y-axis ratio (DPPXYR) on rater evaluations of functional relation and effect size in SCD data sets. Twenty-nine individuals (58.6% male) with experience in SCD were asked to evaluate 40 multiple baseline data sets. Two data sets reporting null, small, moderate, and large intervention effects (8 total) were modified by manipulating the ratio of the x- to y-axis (5 variations), resulting in 40 total graphs. Results indicate that raters scored effects as larger as the DPPXYR decreased. Additionally, a 2-way within-subjects analysis of variance (ANOVA) revealed a significant main effect of DPPXYR manipulation on effect size rating, F(2.11, 58.98) = 58.05, p < .001, η2 = .675, and an interaction between DPPXYR manipulation and magnitude of effect, F(6.71, 187.78) = 11.45, p < .001, η2 = .29. Overall, results of the study indicate researchers and practitioners should maintain a DPPXYR of .14 or larger in the interest of more conservative effect size judgments. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Address Points - COUNTY_ADDRESS_POINTS_IDHS_IN: Address Points Maintained by County Agencies in Indiana (Indiana Department of Homeland Security, Point feature class)

Data.gov (United States)

NSGIC State | GIS Inventory — COUNTY_ADDRESS_POINTS_IDHS_IN is an ESRI Geodatabase point feature class that contains address points maintained by county agencies in Indiana, provided by personnel...

Thermal shock cracking of GSO single crystal

International Nuclear Information System (INIS)

Miyazaki, Noriyuki; Yamamoto, Kazunari; Tamura, Takaharu; Kurashige, Kazuhisa; Ishibashi, Hiroyuki; Susa, Kenzo

1998-01-01

The quantitative estimation of the failure stress of a gadolinium orthosilicate (Gd 2 SiO 5 , hereafter abbreviated as GSO) single crystal due to thermal shock was investigated. A cylindrical test specimen was heated in a silicone oil bath, then subjected to thermal shock by pouring room temperature silicone oil. Cracking occurred during cooling. The heat conduction analysis was performed to obtain temperature distribution in a GSO single crystal at cracking, using the surface temperatures measured in the thermal shock cracking test. Then the thermal stress was calculated using temperature profile of the test specimen obtained from the heat conduction analysis. It is found from the results of the thermal stress analysis and the observation of the cracking in test specimens that the thermal shock cracking occurs in a cleavage plane due to the stress normal to the plane. Three-point bending tests were also performed to examine the relationship between the critical stress for thermal shock cracking and the three-point bending strength obtained from small-sized test specimens. (author)

Beginning SharePoint 2010 Building Business Solutions with SharePoint

CERN Document Server

Perran, Amanda; Mason, Jennifer; Rogers, Laura

2010-01-01

Two SharePoint MVPs provide the ultimate introduction to SharePoint 2010Beginning SharePoint 2010: Building Team Solutions with SharePoint provides information workers and site managers with extensive knowledge and expert advice, empowering them to become SharePoint champions within their organizations.Provides expansive coverage of SharePoint topics, as well as specialty areas such as forms, excel services, records management, and web content managementDetails realistic usage scenarios, and includes practice examples that highlight best practices for configuration and customizationIncludes de

Triana Safehold: A New Gyroless, Sun-Pointing Attitude Controller

Science.gov (United States)

Chen, J.; Morgenstern, Wendy; Garrick, Joseph

2001-01-01

Triana is a single-string spacecraft to be placed in a halo orbit about the sun-earth Ll Lagrangian point. The Attitude Control Subsystem (ACS) hardware includes four reaction wheels, ten thrusters, six coarse sun sensors, a star tracker, and a three-axis Inertial Measuring Unit (IMU). The ACS Safehold design features a gyroless sun-pointing control scheme using only sun sensors and wheels. With this minimum hardware approach, Safehold increases mission reliability in the event of a gyroscope anomaly. In place of the gyroscope rate measurements, Triana Safehold uses wheel tachometers to help provide a scaled estimation of the spacecraft body rate about the sun vector. Since Triana nominally performs momentum management every three months, its accumulated system momentum can reach a significant fraction of the wheel capacity. It is therefore a requirement for Safehold to maintain a sun-pointing attitude even when the spacecraft system momentum is reasonably large. The tachometer sun-line rate estimation enables the controller to bring the spacecraft close to its desired sun-pointing attitude even with reasonably high system momentum and wheel drags. This paper presents the design rationale behind this gyroless controller, stability analysis, and some time-domain simulation results showing performances with various initial conditions. Finally, suggestions for future improvements are briefly discussed.

Survey of billing and coding for counterstrain tender points.

Science.gov (United States)

Snider, Karen T; Johnson, Jane C

2012-06-01

The names of certain counterstrain tender points are incongruent with their physical locations because of an assumption that these points are reflective of dysfunction in neighboring body areas. Because the body area that is physically examined does not always match the body region in which somatic dysfunction is diagnosed for these tender points, it is not always clear which evaluation and management service codes should be used for billing physician services. To assess the attitudes of osteopathic physicians toward the billing and coding of incongruent counterstrain tender points. Physician members of the American Academy of Osteopathy who use counterstrain in clinical practice were surveyed regarding the body area that they would physically examine when assessing for incongruent tender points and, if tender points were present, the body regions to which they would assign somatic dysfunction for billing and coding purposes. Physician responses were categorized as indicating a structural approach (ie, reflective of anatomic location) or a functional approach (ie, reflective of dysfunction in neighboring body areas) to tender point examination and treatment. Associations between sex, specialty, and years in practice with the approach chosen were also examined. Of 175 physicians who responded to the survey, 156 met the study criteria. Respondents were primarily board-certified in neuromusculoskeletal medicine/osteopathic manipulative medicine (98 [63%]), special proficiency in osteopathic manipulative medicine (30 [19%]), or family practice/family practice and osteopathic manipulative treatment (94 [60%]). Ninety percent of physicians predominantly chose responses indicating a structural approach to the physical examination of tender points and 21% predominantly chose responses indicating a functional approach to somatic dysfunction diagnosis. There were inconsistencies among individual respondents regarding the type of approach chosen for a single tender point. For

Role of Erosion in Shaping Point Bars

Science.gov (United States)

Moody, J.; Meade, R.

2012-04-01

A powerful metaphor in fluvial geomorphology has been that depositional features such as point bars (and other floodplain features) constitute the river's historical memory in the form of uniformly thick sedimentary deposits waiting for the geomorphologist to dissect and interpret the past. For the past three decades, along the channel of Powder River (Montana USA) we have documented (with annual cross-sectional surveys and pit trenches) the evolution of the shape of three point bars that were created when an extreme flood in 1978 cut new channels across the necks of two former meander bends and radically shifted the location of a third bend. Subsequent erosion has substantially reshaped, at different time scales, the relic sediment deposits of varying age. At the weekly to monthly time scale (i.e., floods from snowmelt or floods from convective or cyclonic storms), the maximum scour depth was computed (by using a numerical model) at locations spaced 1 m apart across the entire point bar for a couple of the largest floods. The maximum predicted scour is about 0.22 m. At the annual time scale, repeated cross-section topographic surveys (25 during 32 years) indicate that net annual erosion at a single location can be as great as 0.5 m, and that the net erosion is greater than net deposition during 8, 16, and 32% of the years for the three point bars. On average, the median annual net erosion was 21, 36, and 51% of the net deposition. At the decadal time scale, an index of point bar preservation often referred to as completeness was defined for each cross section as the percentage of the initial deposit (older than 10 years) that was still remaining in 2011; computations indicate that 19, 41, and 36% of the initial deposits of sediment were eroded. Initial deposits were not uniform in thickness and often represented thicker pods of sediment connected by thin layers of sediment or even isolated pods at different elevations across the point bar in response to multiple

High resolution surface scanning of Thick-GEM for single photo-electron detection

Energy Technology Data Exchange (ETDEWEB)

Hamar, G., E-mail: hamar.gergo@wigner.mta.hu [Wigner Research Centre for Physics, Budapest (Hungary); Varga, D., E-mail: vdezso@mail.cern.ch [Eoetvoes Lorand University, Budapest (Hungary)

2012-12-01

An optical system for high resolution scanning of TGEM UV photon detection systems is introduced. The structure exploits the combination of a single Au-coated TGEM under study, and an asymmetric MWPC (Close Cathode Chamber) as post-amplification stage. A pulsed UV LED source with emission down to 240 nm has been focused to a spot of 0.07 mm on the TGEM surface, and single photo-electron charge spectra has been recorded over selected two dimensional regions. This way, the TGEM gain (order of 10-100) and TGEM photo-electron detection efficiency is clearly separated, unlike in case of continuous illumination. The surface structure connected to the TGEM photon detection is well observable, including inefficiencies in the holes and at the symmetry points between holes. The detection efficiency as well as the gas gain are fluctuating from hole to hole. The gain is constant in the hexagon around any hole, pointing to the fact that the gain depends on hole geometry, and less on the position where the electron enters. The detection probability map strongly changes with the field strength above the TGEM surface, in relation to the change of the actual surface field configuration. The results can be confronted with position-dependent simulations of TGEM electron transfer and gas multiplication. -- Highlights: Black-Right-Pointing-Pointer First demonstration of Thick GEM surface scanning with single photo-electrons. Black-Right-Pointing-Pointer Resolution of 0.1 mm is sufficient to identify structures connected to TGEM surface field structure. Black-Right-Pointing-Pointer Gain and detection efficiency and separately measurable. Black-Right-Pointing-Pointer Detection efficiency is high in a ring around the holes, and gain is constant in the hexagonal collection regions.

Correlation among electronegativity, cation polarizability, optical basicity and single bond strength of simple oxides

Energy Technology Data Exchange (ETDEWEB)

Dimitrov, Vesselin, E-mail: vesselin@uctm.edu [Department of Silicate Technology, University of Chemical Technology and Metallurgy, 8, Kl. Ohridski Blvd., Sofia 1756 (Bulgaria); Komatsu, Takayuki, E-mail: komatsu@mst.nagaokaut.ac.jp [Department of Materials Science and Technology, Nagaoka University of Technology, 1603-1 Kamitomioka-cho, Nagaoka 940-2188 (Japan)

2012-12-15

A suitable relationship between free-cation polarizability and electronegativity of elements in different valence states and with the most common coordination numbers has been searched on the basis of the similarity in physical nature of both quantities. In general, the cation polarizability increases with decreasing element electronegativity. A systematic periodic change in the polarizability against the electronegativity has been observed in the isoelectronic series. It has been found that generally the optical basicity increases and the single bond strength of simple oxides decreases with decreasing the electronegativity. The observed trends have been discussed on the basis of electron donation ability of the oxide ions and type of chemical bonding in simple oxides. - Graphical abstract: This figure shows the single bond strength of simple oxides as a function of element electronegativity. A remarkable correlation exists between these independently obtained quantities. High values of electronegativity correspond to high values of single bond strength and vice versa. It is obvious that the observed trend in this figure is closely related to the type of chemical bonding in corresponding oxide. Highlights: Black-Right-Pointing-Pointer A suitable relationship between free-cation polarizability and electronegativity of elements was searched. Black-Right-Pointing-Pointer The cation polarizability increases with decreasing element electronegativity. Black-Right-Pointing-Pointer The single bond strength of simple oxides decreases with decreasing the electronegativity. Black-Right-Pointing-Pointer The observed trends were discussed on the basis of type of chemical bonding in simple oxides.

Assessment of left ventricular function with single breath-hold highly accelerated cine MRI combined with guide-point modeling

International Nuclear Information System (INIS)

Heilmaier, Christina; Nassenstein, Kai; Nielles-Vallespin, Sonia; Zuehlsdorff, Sven; Hunold, Peter; Barkhausen, Joerg

2010-01-01

Purpose: To prospectively assess the performance of highly accelerated cine MRI in multi-orientations combined with a new guide-point modeling post-processing technique (GPM approach) for assessment of left ventricular (LV) function compared to the standard summation of slices method based on a stack of short axis views (SoS approach). Materials and methods: 33 consecutive patients were examined on a 1.5 T scanner with a standard steady state free precession (SSFP) sequence (TR, 3.0 ms; TE, 1.5 m; flip angle (FA), 60 o ; acceleration factor (AF), 2) analyzed with the SoS method and a highly accelerated, single breath-hold temporal parallel acquisition SSFP sequence (TR, 4.6 ms; TE, 1.1 ms; AF, 3) post-processed with the GPM method. LV function values were measured by two independent readers with different experience in cardiac MRI and compared by using the paired t-test and F-test. Inter- and intraobserver agreements were calculated using Bland-Altman-Plots. Results: Mean acquisition and post-processing time was significantly shorter with the GPM approach (15 s/3 min versus 360 s/6 min). For all LV function parameters interobserver agreement between the experienced and non-experienced reader was significantly improved when the GPM approach was used. However, end-diastolic and end-systolic volumes were larger for the GPM technique when compared to the SoS method (P 0.121). In both readers and for all parameters variances did not differ significantly (P ≥ 0.409) and the two approaches showed an excellent linear correlation (r > 0.951). Conclusion: Due to its accurate, fast and reproducible assessment of LV function parameters highly accelerated MRI combined with the GPM technique may become the technique of first choice for assessment of LV function in clinical routine.

Generation, transmission, and detection of terahertz photons on an electrically driven single chip

Energy Technology Data Exchange (ETDEWEB)

Ikushima, Kenji; Ito, Atsushi; Okano, Shun [Department of Applied Physics, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei, Tokyo 184-8588 (Japan)

2014-02-03

We demonstrate single photon counting of terahertz (THz) waves transmitted from a local THz point source through a coplanar two-wire waveguide on a GaAs/AlGaAs single heterostructure crystal. In the electrically driven all-in-one chip, quantum Hall edge transport is used to achieve a noiseless injection current for a monochromatic point source of THz fields. The local THz fields are coupled to a coplanar two-wire metal waveguide and transmitted over a macroscopic scale greater than the wavelength (38 μm in GaAs). THz waves propagating on the waveguide are counted as individual photons by a quantum-dot single-electron transistor on the same chip. Photon counting on integrated high-frequency circuits will open the possibilities for on-chip quantum optical experiments.

Vibration isolation and dual-stage actuation pointing system for space precision payloads

Science.gov (United States)

Kong, Yongfang; Huang, Hai

2018-02-01

Pointing and stability requirements for future space missions are becoming more and more stringent. This work follows the pointing control method which consists of a traditional spacecraft attitude control system and a payload active pointing loop, further proposing a vibration isolation and dual-stage actuation pointing system for space precision payloads based on a soft Stewart platform. Central to the concept is using the dual-stage actuator instead of the traditional voice coil motor single-stage actuator to improve the payload active pointing capability. Based on a specified payload, the corresponding platform was designed to be installed between the spacecraft bus and the payload. The performance of the proposed system is demonstrated by preliminary closed-loop control investigations in simulations. With the ordinary spacecraft bus, the line-of-sight pointing accuracy can be controlled to below a few milliarcseconds in tip and tilt. Meanwhile, utilizing the voice coil motor with the softening spring in parallel, which is a portion of the dual-stage actuator, the system effectively achieves low-frequency motion transmission and high-frequency vibration isolation along the other four degree-of-freedom directions.

Single-chip serial channel enhances multi-processor systems

Energy Technology Data Exchange (ETDEWEB)

Millar, J.

1982-01-01

In this paper multiprocessor systems are described and explained. The impact that VLSI advancements are having on multiprocessor design is pointed out. The TMS 7041 single-chip microcomputer is described briefly, highlighting its multiprocessor communication capability. And finally, a typical multiprocessor system is shown, implementing the TMS 7041.

3D single-molecule super-resolution microscopy with a tilted light sheet.

Science.gov (United States)

Gustavsson, Anna-Karin; Petrov, Petar N; Lee, Maurice Y; Shechtman, Yoav; Moerner, W E

2018-01-09

Tilted light sheet microscopy with 3D point spread functions (TILT3D) combines a novel, tilted light sheet illumination strategy with long axial range point spread functions (PSFs) for low-background, 3D super-localization of single molecules as well as 3D super-resolution imaging in thick cells. Because the axial positions of the single emitters are encoded in the shape of each single-molecule image rather than in the position or thickness of the light sheet, the light sheet need not be extremely thin. TILT3D is built upon a standard inverted microscope and has minimal custom parts. The result is simple and flexible 3D super-resolution imaging with tens of nm localization precision throughout thick mammalian cells. We validate TILT3D for 3D super-resolution imaging in mammalian cells by imaging mitochondria and the full nuclear lamina using the double-helix PSF for single-molecule detection and the recently developed tetrapod PSFs for fiducial bead tracking and live axial drift correction.

Three-point functions in N=4 SYM: the hexagon proposal at three loops

Energy Technology Data Exchange (ETDEWEB)

Eden, Burkhard [Institut für Mathematik & Institut für Physik, Humboldt-Universität zu Berlin,Zum großen Windkanal 6, D-12489 Berlin (Germany); Sfondrini, Alessandro [Institut für Theoretische Physik, ETH Zürich,Wolfgang-Pauli-Str. 27, CH-8093 Zürich (Switzerland)

2016-02-24

Basso, Komatsu and Vieira recently proposed an all-loop framework for the computation of three-point functions of single-trace operators of N=4 super-Yang-Mills, the “hexagon program”. This proposal results in several remarkable predictions, including the three-point function of two protected operators with an unprotected one in the SU(2) and SL(2) sectors. Such predictions consist of an “asymptotic” part — similar in spirit to the asymptotic Bethe Ansatz of Beisert and Staudacher for two-point functions — as well as additional finite-size “wrapping” Lüscher-like corrections. The focus of this paper is on such wrapping corrections, which we compute at three-loops in the SL(2) sector. The resulting structure constants perfectly match the ones obtained in the literature from four-point correlators of protected operators.

Automated calculation of point A coordinates for CT-based high-dose-rate brachytherapy of cervical cancer

Directory of Open Access Journals (Sweden)

Hyejoo Kang

2017-07-01

Full Text Available Purpose: The goal is to develop a stand-alone application, which automatically and consistently computes the coordinates of the dose calculation point recommended by the American Brachytherapy Society (i.e., point A based solely on the implanted applicator geometry for cervical cancer brachytherapy. Material and methods: The application calculates point A coordinates from the source dwell geometries in the computed tomography (CT scans, and outputs the 3D coordinates in the left and right directions. The algorithm was tested on 34 CT scans of 7 patients treated with high-dose-rate (HDR brachytherapy using tandem and ovoid applicators. A single experienced user retrospectively and manually inserted point A into each CT scan, whose coordinates were used as the “gold standard” for all comparisons. The gold standard was subtracted from the automatically calculated points, a second manual placement by the same experienced user, and the clinically used point coordinates inserted by multiple planners. Coordinate differences and corresponding variances were compared using nonparametric tests. Results: Automatically calculated, manually placed, and clinically used points agree with the gold standard to < 1 mm, 1 mm, 2 mm, respectively. When compared to the gold standard, the average and standard deviation of the 3D coordinate differences were 0.35 ± 0.14 mm from automatically calculated points, 0.38 ± 0.21 mm from the second manual placement, and 0.71 ± 0.44 mm from the clinically used point coordinates. Both the mean and standard deviations of the 3D coordinate differences were statistically significantly different from the gold standard, when point A was placed by multiple users (p < 0.05 but not when placed repeatedly by a single user or when calculated automatically. There were no statistical differences in doses, which agree to within 1-2% on average for all three groups. Conclusions: The study demonstrates that the automated algorithm

Point defects in hexagonal germanium carbide monolayer: A first-principles calculation

International Nuclear Information System (INIS)

Ersan, Fatih; Gökçe, Aytaç Gürhan; Aktürk, Ethem

2016-01-01

Highlights: • Semiconductor GeC turns into metal by introducing a carbon vacancy. • Semiconductor GeC becomes half-metal by a single Ge vacancy. • Band gap value of GeC system can be tuned in the range of 0.308–1.738 eV by antisite or Stone–Wales defects. - Abstract: On the basis of first-principles plane-wave calculations, we investigated the electronic and magnetic properties of various point defects including single Ge and C vacancies, Ge + C divacancy, Ge↔C antisites and the Stone–Wales (SW) defects in a GeC monolayer. We found that various periodic vacancy defects in GeC single layer give rise to crucial effects on the electronic and magnetic properties. The band gaps of GeC monolayer vary significantly from 0.308 eV to 1.738 eV due to the presence of antisites and Stone–Wales defects. While nonmagnetic ground state of semiconducting GeC turns into metal by introducing a carbon vacancy, it becomes half-metal by a single Ge vacancy with high magnetization (4 μ_B) value per supercell. All the vacancy types have zero net magnetic moments, except single Ge vacancy.

Point defects in hexagonal germanium carbide monolayer: A first-principles calculation

Energy Technology Data Exchange (ETDEWEB)

Ersan, Fatih [Department of Physics, Adnan Menderes University, 09100 Aydın (Turkey); Gökçe, Aytaç Gürhan [Department of Physics, Adnan Menderes University, 09100 Aydın (Turkey); Department of Physics, Dokuz Eylül University, 35160 İzmir (Turkey); Aktürk, Ethem, E-mail: ethem.akturk@adu.edu.tr [Department of Physics, Adnan Menderes University, 09100 Aydın (Turkey); Nanotechnology Application and Research Center, Adnan Menderes University, 09100 Aydın (Turkey)

2016-12-15

Highlights: • Semiconductor GeC turns into metal by introducing a carbon vacancy. • Semiconductor GeC becomes half-metal by a single Ge vacancy. • Band gap value of GeC system can be tuned in the range of 0.308–1.738 eV by antisite or Stone–Wales defects. - Abstract: On the basis of first-principles plane-wave calculations, we investigated the electronic and magnetic properties of various point defects including single Ge and C vacancies, Ge + C divacancy, Ge↔C antisites and the Stone–Wales (SW) defects in a GeC monolayer. We found that various periodic vacancy defects in GeC single layer give rise to crucial effects on the electronic and magnetic properties. The band gaps of GeC monolayer vary significantly from 0.308 eV to 1.738 eV due to the presence of antisites and Stone–Wales defects. While nonmagnetic ground state of semiconducting GeC turns into metal by introducing a carbon vacancy, it becomes half-metal by a single Ge vacancy with high magnetization (4 μ{sub B}) value per supercell. All the vacancy types have zero net magnetic moments, except single Ge vacancy.

Rational points on varieties

CERN Document Server

Poonen, Bjorn

2017-01-01

This book is motivated by the problem of determining the set of rational points on a variety, but its true goal is to equip readers with a broad range of tools essential for current research in algebraic geometry and number theory. The book is unconventional in that it provides concise accounts of many topics instead of a comprehensive account of just one-this is intentionally designed to bring readers up to speed rapidly. Among the topics included are Brauer groups, faithfully flat descent, algebraic groups, torsors, étale and fppf cohomology, the Weil conjectures, and the Brauer-Manin and descent obstructions. A final chapter applies all these to study the arithmetic of surfaces. The down-to-earth explanations and the over 100 exercises make the book suitable for use as a graduate-level textbook, but even experts will appreciate having a single source covering many aspects of geometry over an unrestricted ground field and containing some material that cannot be found elsewhere. The origins of arithmetic (o...

Tipping Point

Medline Plus

Full Text Available ... en español Blog About OnSafety CPSC Stands for Safety The Tipping Point Home > 60 Seconds of Safety (Videos) > The Tipping Point The Tipping Point by ... danger death electrical fall furniture head injury product safety television tipover tv Watch the video in Adobe ...

Noise evaluation of a point autofocus surface topography measuring instrument

Science.gov (United States)

Maculotti, Giacomo; Feng, Xiaobing; Galetto, Maurizio; Leach, Richard

2018-06-01

In this work, the measurement noise of a point autofocus surface topography measuring instrument is evaluated, as the first step towards establishing a route to traceability for this type of instrument. The evaluation is based on the determination of the metrological characteristics for noise as outlined in draft ISO specification standards by using a calibrated optical flat. The static noise and repeatability of the autofocus sensor are evaluated. The influence of environmental disturbances on the measured surface topography and the built-in software to compensate for such influences are also investigated. The instrument was found to have a measurement noise of approximately 2 nm or, when expressed with the measurement bandwidth, 0.4 nm for a single-point measurement.

Transmission electron microscopy of single and double aged 718Plus superalloy

Energy Technology Data Exchange (ETDEWEB)

Whitmore, Lawrence, E-mail: lawrence.whitmore@unileoben.ac.at [Christian Doppler Laboratory for Early Stages of Precipitation, Department of Physical Metallurgy and Materials Testing, Montanuniversitaet Leoben, Franz-Josef Strasse 18, 8700 Leoben (Austria); Leitner, Harald [Christian Doppler Laboratory for Early Stages of Precipitation, Department of Physical Metallurgy and Materials Testing, Montanuniversitaet Leoben, Franz-Josef Strasse 18, 8700 Leoben (Austria); Povoden-Karadeniz, Erwin [Christian Doppler Laboratory for Early Stages of Precipitation, Vienna University of Technology, Favoritenstrasse 9-11, A-1040 Vienna (Austria); Radis, Rene [Christian Doppler Laboratory for Early Stages of Precipitation, Vienna University of Technology, Favoritenstrasse 9-11, A-1040 Vienna (Austria); Institute for Materials Science and Welding, Graz University of Technology, Kopernikusgasse 24, A-8010 Graz (Austria); Stockinger, Martin [Boehler Schmiedetechnik GmbH Co KG, Mariazellerstrasse 25, 8600 Kapfenberg (Austria)

2012-02-01

Highlights: Black-Right-Pointing-Pointer Volume fraction and size of {gamma} Prime precipitates increases with double aging. Black-Right-Pointing-Pointer Increase in hardness is explained by the size and phase fraction of {gamma} Prime precipitates. Black-Right-Pointing-Pointer Anti-phase boundary energy in the {gamma} Prime is estimated to be 0.2 Jm{sup -2}. Black-Right-Pointing-Pointer Ni, Ti, Al and Nb increase in the {gamma} Prime phase, Fe, Co, Cr, Mo and W decrease. Black-Right-Pointing-Pointer Evidence of a dense population of {gamma} Prime clusters 1-2 nm found. - Abstract: The effects of single and double aging upon the ATI 718Plus Nickel superalloy are investigated. Double aging is found to produce an increase in hardness as compared to single aging, thus an extensive micro-structural study is performed to identify and understand the physical reasons for this. Precipitation of the {gamma} Prime phase is of particular interest in this case. Using transmission electron microscopy and energy dispersive X-ray spectroscopy, the {gamma} Prime shape, size, number density and elemental constitution are investigated and correlated to the aging conditions. The {gamma}/{gamma} Prime lattice misfit is also measured. Only one main population of {gamma} Prime precipitates is observed after double aging: simply the population produced during the first aging continues to evolve. Using a theoretical model for precipitation hardening, based on the shearing of precipitates, the hardness is related to the size and phase fraction of the {gamma} Prime and a value for the anti-phase boundary energy of the {gamma} Prime is calculated. Measurements are compared with thermo-kinetic simulation using the software package MatCalc. A dense dispersion of 1-2 nm size {gamma} Prime phase clusters is additionally observed after both single and double aging, and this is correlated through simulation with the final cooling stage of the heat treatment.

Angular and magnetic field dependences of critical current in irradiated YBaCuO single crystals

International Nuclear Information System (INIS)

Petrusenko, Yu.

2010-01-01

The investigation of mechanisms responsible for the current-carrying capability of irradiated high-temperature superconductors (HTSC) was realized. For the purpose, experiments were made to investigate the effect of point defects generated by high-energy electron irradiation on the critical temperature and the critical current in high-Tc superconducting single crystals YBa 2 Cu 3 O 7-x . The transport current density measured in HTSC single crystals YBa 2 Cu 3 O 7-x by the dc-method was found to exceed 80000 A/cm 2 . The experiments have demonstrated a more than 30-fold increase in the critical current density in single crystals irradiated with 2.5 MeV electrons to a dose of 3·10 18 el/cm 2 . Detailed studies were made into the anisotropy of critical current and the dependence of critical current on the external magnetic field strength in irradiated single crystals. A high efficiency of point defects as centers of magnetic vortex pinning in HTSC single crystals was first demonstrated.

Single-subject withdrawal designs in delayed matching-to-sample procedures

OpenAIRE

Eilifsen, Christoffer; Arntzen, Erik

2011-01-01

In most studies of delayed matching-to-sample (DMTS) and stimulus equivalence, the delay has remained fixed throughout a single experimental condition. We wanted to expand on the DMTS and stimulus equivalence literature by examining the effects of using titrating delays with different starting points during the establishment of conditional discriminations prerequisite for stimulus equivalence. In Experiment 1, a variation of a single-subject withdrawal design was used. Ten adults were exposed...

A tri-reference point theory of decision making under risk.

Science.gov (United States)

Wang, X T; Johnson, Joseph G

2012-11-01

The tri-reference point (TRP) theory takes into account minimum requirements (MR), the status quo (SQ), and goals (G) in decision making under risk. The 3 reference points demarcate risky outcomes and risk perception into 4 functional regions: success (expected value of x ≥ G), gain (SQ G > SQ. We present TRP assumptions and value functions and a mathematical formalization of the theory. We conducted empirical tests of crucial TRP predictions using both explicit and implicit reference points. We show that decision makers consider both G and MR and give greater weight to MR than G, indicating failure aversion (i.e., the disutility of a failure is greater than the utility of a success in the same task) in addition to loss aversion (i.e., the disutility of a loss is greater than the utility of the same amount of gain). Captured by a double-S shaped value function with 3 inflection points, risk preferences switched between risk seeking and risk aversion when the distribution of a gamble straddled a different reference point. The existence of MR (not G) significantly shifted choice preference toward risk aversion even when the outcome distribution of a gamble was well above the MR. Single reference point based models such as prospect theory cannot consistently account for these findings. The TRP theory provides simple guidelines for evaluating risky choices for individuals and organizational management. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

Point-of-care rare cell cancer diagnostics.

Science.gov (United States)

Issadore, David

2015-01-01

The sparse cells that are shed from tumors into peripheral circulation are an increasingly promising resource for noninvasive monitoring of cancer progression, early diagnosis of disease, and serve as a tool for improving our understanding of cancer metastasis. However, the extremely sparse concentration of circulating tumor cells (CTCs) in blood (~1-100 CTC in 7.5 mL of blood) as well as their heterogeneous biomarker expression has limited their detection using conventional laboratory techniques. To overcome these challenges, we have developed a microfluidic chip-based micro-Hall detector (μHD), which can directly measure single, immunomagnetically tagged cells in whole blood. The μHD can detect individual cells even in the presence of vast numbers of blood cells and unbound reactants, and does not require any washing or purification steps. Furthermore, this cost-effective, single-cell analytical technique is well suited for miniaturization into a mobile platform for low-cost point-of-care use. In this chapter, we describe the methodology used to design, fabricate, and apply these chips to cancer diagnostics.

Response of single polymers to localized step strains

NARCIS (Netherlands)

Panja, D.

2009-01-01

In this paper, the response of single three-dimensional phantom and self-avoiding polymers to localized step strains are studied for two cases in the absence of hydrodynamic interactions: (i) Polymers tethered at one end with the strain created at the point of tether, and (ii) free polymers with the

Bounded estimation of flux-at-a-point for one or more detectors

International Nuclear Information System (INIS)

Steinberg, H.A.

1974-01-01

The procedure for biasing the collision density of Monte Carlo particles, so that the estimation of flux at a point detector is bounded, is described. The theory and program design of the solution of the problem of obtaining estimates for several detectors during a single Monte Carlo calculation is presented. 4 references. (U.S.)

Null point of discrimination in crustacean polarisation vision.

Science.gov (United States)

How, Martin J; Christy, John; Roberts, Nicholas W; Marshall, N Justin

2014-07-15

The polarisation of light is used by many species of cephalopods and crustaceans to discriminate objects or to communicate. Most visual systems with this ability, such as that of the fiddler crab, include receptors with photopigments that are oriented horizontally and vertically relative to the outside world. Photoreceptors in such an orthogonal array are maximally sensitive to polarised light with the same fixed e-vector orientation. Using opponent neural connections, this two-channel system may produce a single value of polarisation contrast and, consequently, it may suffer from null points of discrimination. Stomatopod crustaceans use a different system for polarisation vision, comprising at least four types of polarisation-sensitive photoreceptor arranged at 0, 45, 90 and 135 deg relative to each other, in conjunction with extensive rotational eye movements. This anatomical arrangement should not suffer from equivalent null points of discrimination. To test whether these two systems were vulnerable to null points, we presented the fiddler crab Uca heteropleura and the stomatopod Haptosquilla trispinosa with polarised looming stimuli on a modified LCD monitor. The fiddler crab was less sensitive to differences in the degree of polarised light when the e-vector was at -45 deg than when the e-vector was horizontal. In comparison, stomatopods showed no difference in sensitivity between the two stimulus types. The results suggest that fiddler crabs suffer from a null point of sensitivity, while stomatopods do not. © 2014. Published by The Company of Biologists Ltd.

An improved contour symmetry axes extraction algorithm and its application in the location of picking points of apples

Energy Technology Data Exchange (ETDEWEB)

Wang, D.; Song, H.; Yu, X.; Zhang, W.; Qu, W.; Xu, Y.

2015-07-01

The key problem for picking robots is to locate the picking points of fruit. A method based on the moment of inertia and symmetry of apples is proposed in this paper to locate the picking points of apples. Image pre-processing procedures, which are crucial to improving the accuracy of the location, were carried out to remove noise and smooth the edges of apples. The moment of inertia method has the disadvantage of high computational complexity, which should be solved, so convex hull was used to improve this problem. To verify the validity of this algorithm, a test was conducted using four types of apple images containing 107 apple targets. These images were single and unblocked apple images, single and blocked apple images, images containing adjacent apples, and apples in panoramas. The root mean square error values of these four types of apple images were 6.3, 15.0, 21.6 and 18.4, respectively, and the average location errors were 4.9°, 10.2°, 16.3° and 13.8°, respectively. Furthermore, the improved algorithm was effective in terms of average runtime, with 3.7 ms and 9.2 ms for single and unblocked and single and blocked apple images, respectively. For the other two types of apple images, the runtime was determined by the number of apples and blocked apples contained in the images. The results showed that the improved algorithm could extract symmetry axes and locate the picking points of apples more efficiently. In conclusion, the improved algorithm is feasible for extracting symmetry axes and locating the picking points of apples. (Author)

Double point source W-phase inversion: Real-time implementation and automated model selection

Science.gov (United States)

Nealy, Jennifer; Hayes, Gavin

2015-01-01

Rapid and accurate characterization of an earthquake source is an extremely important and ever evolving field of research. Within this field, source inversion of the W-phase has recently been shown to be an effective technique, which can be efficiently implemented in real-time. An extension to the W-phase source inversion is presented in which two point sources are derived to better characterize complex earthquakes. A single source inversion followed by a double point source inversion with centroid locations fixed at the single source solution location can be efficiently run as part of earthquake monitoring network operational procedures. In order to determine the most appropriate solution, i.e., whether an earthquake is most appropriately described by a single source or a double source, an Akaike information criterion (AIC) test is performed. Analyses of all earthquakes of magnitude 7.5 and greater occurring since January 2000 were performed with extended analyses of the September 29, 2009 magnitude 8.1 Samoa earthquake and the April 19, 2014 magnitude 7.5 Papua New Guinea earthquake. The AIC test is shown to be able to accurately select the most appropriate model and the selected W-phase inversion is shown to yield reliable solutions that match published analyses of the same events.

A Hybrid Maximum Power Point Search Method Using Temperature Measurements in Partial Shading Conditions

Directory of Open Access Journals (Sweden)

Mroczka Janusz

2014-12-01

Full Text Available Photovoltaic panels have a non-linear current-voltage characteristics to produce the maximum power at only one point called the maximum power point. In the case of the uniform illumination a single solar panel shows only one maximum power, which is also the global maximum power point. In the case an irregularly illuminated photovoltaic panel many local maxima on the power-voltage curve can be observed and only one of them is the global maximum. The proposed algorithm detects whether a solar panel is in the uniform insolation conditions. Then an appropriate strategy of tracking the maximum power point is taken using a decision algorithm. The proposed method is simulated in the environment created by the authors, which allows to stimulate photovoltaic panels in real conditions of lighting, temperature and shading.

Nonlinear Dynamics, Fixed Points and Coupled Fixed Points in Generalized Gauge Spaces with Applications to a System of Integral Equations

Directory of Open Access Journals (Sweden)

Adrian Petruşel

2015-01-01

Full Text Available We will discuss discrete dynamics generated by single-valued and multivalued operators in spaces endowed with a generalized metric structure. More precisely, the behavior of the sequence (fn(xn∈N of successive approximations in complete generalized gauge spaces is discussed. In the same setting, the case of multivalued operators is also considered. The coupled fixed points for mappings t1:X1×X2→X1 and t2:X1×X2→X2 are discussed and an application to a system of nonlinear integral equations is given.

A single-beam titration method for the quantification of open-path Fourier transform infrared spectroscopy

International Nuclear Information System (INIS)

Sung, Lung-Yu; Lu, Chia-Jung

2014-01-01

This study introduced a quantitative method that can be used to measure the concentration of analytes directly from a single-beam spectrum of open-path Fourier Transform Infrared Spectroscopy (OP-FTIR). The peak shapes of the analytes in a single-beam spectrum were gradually canceled (i.e., “titrated”) by dividing an aliquot of a standard transmittance spectrum with a known concentration, and the sum of the squared differential synthetic spectrum was calculated as an indicator for the end point of this titration. The quantity of a standard transmittance spectrum that is needed to reach the end point can be used to calculate the concentrations of the analytes. A NIST traceable gas standard containing six known compounds was used to compare the quantitative accuracy of both this titration method and that of a classic least square (CLS) using a closed-cell FTIR spectrum. The continuous FTIR analysis of industrial exhausting stack showed that concentration trends were consistent between the CLS and titration methods. The titration method allowed the quantification to be performed without the need of a clean single-beam background spectrum, which was beneficial for the field measurement of OP-FTIR. Persistent constituents of the atmosphere, such as NH 3 , CH 4 and CO, were successfully quantified using the single-beam titration method with OP-FTIR data that is normally inaccurate when using the CLS method due to the lack of a suitable background spectrum. Also, the synthetic spectrum at the titration end point contained virtually no peaks of analytes, but it did contain the remaining information needed to provide an alternative means of obtaining an ideal single-beam background for OP-FTIR. - Highlights: • Establish single beam titration quantification method for OP-FTIR. • Define the indicator for the end-point of spectrum titration. • An ideal background spectrum can be obtained using single beam titration. • Compare the quantification between titration

Point-of-Care Determination of Acetaminophen Levels with Multi-Hydrogen Bond Manipulated Single-Molecule Recognition (eMuHSiR).

Science.gov (United States)

Zhang, Yan; Huang, Zhongyuan; Wang, Letao; Wang, Chunming; Zhang, Changde; Wiese, Tomas; Wang, Guangdi; Riley, Kevin; Wang, Zhe

2018-04-03

This work aims to face the challenge of monitoring small molecule drugs accurately and rapidly for point-of-care (POC) diagnosis in current clinical settings. Overdose of acetaminophen (AP), a commonly used over the counter (OTC) analgesic drug, has been determined to be a major cause of acute liver failure in the US and the UK. However, there is no rapid and accurate detection method available for this drug in the emergency room. The present study examined an AP sensing strategy that relies on a previously unexplored strong interaction between AP and the arginine (Arg) molecule. It was found that as many as 4 hydrogen bonds can be formed between one Arg molecule and one AP molecule. By taking advantages of this structural selectivity and high tenability of hydrogen bonds, Arg, immobilized on a graphene surface via electrostatic interactions, was utilized to structurally capture AP. Interestingly, bonded AP still remained the perfect electrochemical activities. The extent of Arg-AP bonds was quantified using a newly designed electrochemical (EC) sensor. To verify the feasibility of this novel assay, based on multihydrogen bond manipulated single-molecule recognition (eMuHSiR), both pharmaceutical and serum sample were examined. In commercial tablet measurement, no significant difference was seen between the results of eMuHSiR and other standard methods. For measuring AP concentration in the mice blood, the substances in serum, such as sugars and fats, would not bring any interference to the eMuHSiR in a wide concentration range. This eMuHSiR method opens the way for future development of small molecule detection for the POC testing.

New directions in point-contact spectroscopy based on scanning tunneling microscopy techniques (Review Article)

International Nuclear Information System (INIS)

Tartaglini, E.; Verhagen, T.G.A.; Galli, F.; Trouwborst, M.L.; Aarts, J.; Van-Ruitebbeek, J.M.; Muller, R.; Shiota, T.

2013-01-01

Igor Yanson showed 38 years ago for the first time a point-contact measurement where he probed the energy resolved spectroscopy of the electronic scattering inside the metal. Since this first measurement, the pointcontact spectroscopy (PCS) technique improved enormously. The application of the scanning probe microscopy (SPM) techniques in the late 1980s allowed achieving contacts with a diameter of a single atom. With the introduction of the mechanically controlled break junction technique, even spectroscopy on freely suspended chains of atoms could be performed. In this paper, we briefly review the current developments of PCS and show recent experiments in advanced scanning PCS based on SPM techniques. We describe some results obtained with both needle-anvil type of point contacts and scanning tunneling microscopy (STM). We also show our first attempt to lift up with a STM a chain of single gold atoms from a Au(110) surface.

Fast and flexible selection with a single switch.

Directory of Open Access Journals (Sweden)

Tamara Broderick

Full Text Available Selection methods that require only a single-switch input, such as a button click or blink, are potentially useful for individuals with motor impairments, mobile technology users, and individuals wishing to transmit information securely. We present a single-switch selection method, "Nomon," that is general and efficient. Existing single-switch selection methods require selectable options to be arranged in ways that limit potential applications. By contrast, traditional operating systems, web browsers, and free-form applications (such as drawing place options at arbitrary points on the screen. Nomon, however, has the flexibility to select any point on a screen. Nomon adapts automatically to an individual's clicking ability; it allows a person who clicks precisely to make a selection quickly and allows a person who clicks imprecisely more time to make a selection without error. Nomon reaps gains in information rate by allowing the specification of beliefs (priors about option selection probabilities and by avoiding tree-based selection schemes in favor of direct (posterior inference. We have developed both a Nomon-based writing application and a drawing application. To evaluate Nomon's performance, we compared the writing application with a popular existing method for single-switch writing (row-column scanning. Novice users wrote 35% faster with the Nomon interface than with the scanning interface. An experienced user (author TB, with 10 hours practice wrote at speeds of 9.3 words per minute with Nomon, using 1.2 clicks per character and making no errors in the final text.

Point-to-point people with purpose—Exploring the possibility of a commercial traveler market for point-to-point suborbital space transportation

Science.gov (United States)

Webber, Derek

2013-12-01

An argument was made at the First Arcachon Conference on Private Human Access to Space in 2008 [1] that some systematic market research should be conducted into potential market segments for point-to-point suborbital space transportation (PtP), in order to understand whether a commercial market exists which might augment possible government use for such a vehicle. The cargo market potential was subsequently addressed via desk research, and the results, which resulted in a pessimistic business case outlook, were presented in [2]. The same desk research approach is now used in this paper to address the potential business and wealthy individual passenger traveler market segment ("point-to-point people with purpose"). The results, with the assumed ticket pricing, are not encouraging.

HIERARCHICAL REGULARIZATION OF POLYGONS FOR PHOTOGRAMMETRIC POINT CLOUDS OF OBLIQUE IMAGES

Directory of Open Access Journals (Sweden)

L. Xie

2017-05-01

Full Text Available Despite the success of multi-view stereo (MVS reconstruction from massive oblique images in city scale, only point clouds and triangulated meshes are available from existing MVS pipelines, which are topologically defect laden, free of semantical information and hard to edit and manipulate interactively in further applications. On the other hand, 2D polygons and polygonal models are still the industrial standard. However, extraction of the 2D polygons from MVS point clouds is still a non-trivial task, given the fact that the boundaries of the detected planes are zigzagged and regularities, such as parallel and orthogonal, cannot preserve. Aiming to solve these issues, this paper proposes a hierarchical polygon regularization method for the photogrammetric point clouds from existing MVS pipelines, which comprises of local and global levels. After boundary points extraction, e.g. using alpha shapes, the local level is used to consolidate the original points, by refining the orientation and position of the points using linear priors. The points are then grouped into local segments by forward searching. In the global level, regularities are enforced through a labeling process, which encourage the segments share the same label and the same label represents segments are parallel or orthogonal. This is formulated as Markov Random Field and solved efficiently. Preliminary results are made with point clouds from aerial oblique images and compared with two classical regularization methods, which have revealed that the proposed method are more powerful in abstracting a single building and is promising for further 3D polygonal model reconstruction and GIS applications.

Generalized correlation of latent heats of vaporization of coal liquid model compounds between their freezing points and critical points

Energy Technology Data Exchange (ETDEWEB)

Sivaraman, A.; Kobuyashi, R.; Mayee, J.W.

1984-02-01

Based on Pitzer's three-parameter corresponding states principle, the authors have developed a correlation of the latent heat of vaporization of aromatic coal liquid model compounds for a temperature range from the freezing point to the critical point. An expansion of the form L = L/sub 0/ + ..omega..L /sub 1/ is used for the dimensionless latent heat of vaporization. This model utilizes a nonanalytic functional form based on results derived from renormalization group theory of fluids in the vicinity of the critical point. A simple expression for the latent heat of vaporization L = D/sub 1/epsilon /SUP 0.3333/ + D/sub 2/epsilon /SUP 0.8333/ + D/sub 4/epsilon /SUP 1.2083/ + E/sub 1/epsilon + E/sub 2/epsilon/sup 2/ + E/sub 3/epsilon/sup 3/ is cast in a corresponding states principle correlation for coal liquid compounds. Benzene, the basic constituent of the functional groups of the multi-ring coal liquid compounds, is used as the reference compound in the present correlation. This model works very well at both low and high reduced temperatures approaching the critical point (0.02 < epsilon = (T /SUB c/ - T)/(T /SUB c/- 0.69)). About 16 compounds, including single, two, and three-ring compounds, have been tested and the percent root-mean-square deviations in latent heat of vaporization reported and estimated through the model are 0.42 to 5.27%. Tables of the coefficients of L/sub 0/ and L/sub 1/ are presented. The contributing terms of the latent heat of vaporization function are also presented in a table for small increments of epsilon.

Implementation of single qubit in QD ensembles

International Nuclear Information System (INIS)

Alegre, T.P. Mayer

2004-01-01

Full text: During the last decades the semiconductor industry has achieved the production of exponentially shrinking components. This fact points to fundamental limits of integration, making computation with single atoms or particles like an electron an ultimate goal. To get to this limit, quantum systems in solid state have to be manipulated in a controllable fashion. The assessment of quantum degrees of freedom for information processing may allow exponentially faster performance for certain classes of problems. The essential aspect to be explored in quantum information processing resides in the superposition of states that allows resources such as entangled states to be envisaged. The quest for the optimal system to host a quantum variable that is sufficiently isolated from the environment encompasses implementations spanning optical, atomic, molecular and solid state systems. In the solid state, a variety of proposals have come forth, each one having its own advantages and disadvantages. The main conclusion from these e efforts is that there is no decisive technology upon which quantum information devices will be built. Self-assembled quantum dots (SAQDs or QDs), can be grown with size uniformity that enables the observation of single electron loading events. They can in turn be used to controllably trap single electrons into discrete levels, atom-like, with their corresponding shells. Hund's rules and Pauli exclusion principle are observed in these nanostructures and are key in allowing and preserving a particular quantum state. Provided that one can trap one electron in a QD ensemble, the corresponding spin can be manipulated by an external magnetic field by either conventional Electron Spin Resonance (ESR) techniques or g-tensor modulation resonance (g-TMR). By analogy with Nuclear Magnetic Resonance, single qubit operations are proposed, which at some point in time should be scaled, provided that spin-spin interactions can be controlled. Read out can be

Hardware-accelerated Point Generation and Rendering of Point-based Impostors

DEFF Research Database (Denmark)

Bærentzen, Jakob Andreas

2005-01-01

This paper presents a novel scheme for generating points from triangle models. The method is fast and lends itself well to implementation using graphics hardware. The triangle to point conversion is done by rendering the models, and the rendering may be performed procedurally or by a black box API....... I describe the technique in detail and discuss how the generated point sets can easily be used as impostors for the original triangle models used to create the points. Since the points reside solely in GPU memory, these impostors are fairly efficient. Source code is available online....

Saddle-points of a two dimensional random lattice theory

International Nuclear Information System (INIS)

Pertermann, D.

1985-07-01

A two dimensional random lattice theory with a free massless scalar field is considered. We analyse the field theoretic generating functional for any given choice of positions of the lattice sites. Asking for saddle-points of this generating functional with respect to the positions we find the hexagonal lattice and a triangulated version of the hypercubic lattice as candidates. The investigation of the neighbourhood of a single lattice site yields triangulated rectangles and regular polygons extremizing the above generating functional on the local level. (author)

Einstein gravity 3-point functions from conformal field theory

Science.gov (United States)

Afkhami-Jeddi, Nima; Hartman, Thomas; Kundu, Sandipan; Tajdini, Amirhossein

2017-12-01

We study stress tensor correlation functions in four-dimensional conformal field theories with large N and a sparse spectrum. Theories in this class are expected to have local holographic duals, so effective field theory in anti-de Sitter suggests that the stress tensor sector should exhibit universal, gravity-like behavior. At the linearized level, the hallmark of locality in the emergent geometry is that stress tensor three-point functions 〈 T T T 〉, normally specified by three constants, should approach a universal structure controlled by a single parameter as the gap to higher spin operators is increased. We demonstrate this phenomenon by a direct CFT calculation. Stress tensor exchange, by itself, violates causality and unitarity unless the three-point functions are carefully tuned, and the unique consistent choice exactly matches the prediction of Einstein gravity. Under some assumptions about the other potential contributions, we conclude that this structure is universal, and in particular, that the anomaly coefficients satisfy a ≈ c as conjectured by Camanho et al. The argument is based on causality of a four-point function, with kinematics designed to probe bulk locality, and invokes the chaos bound of Maldacena, Shenker, and Stanford.

PointCom: semi-autonomous UGV control with intuitive interface

Science.gov (United States)

Rohde, Mitchell M.; Perlin, Victor E.; Iagnemma, Karl D.; Lupa, Robert M.; Rohde, Steven M.; Overholt, James; Fiorani, Graham

2008-04-01

Unmanned ground vehicles (UGVs) will play an important role in the nation's next-generation ground force. Advances in sensing, control, and computing have enabled a new generation of technologies that bridge the gap between manual UGV teleoperation and full autonomy. In this paper, we present current research on a unique command and control system for UGVs named PointCom (Point-and-Go Command). PointCom is a semi-autonomous command system for one or multiple UGVs. The system, when complete, will be easy to operate and will enable significant reduction in operator workload by utilizing an intuitive image-based control framework for UGV navigation and allowing a single operator to command multiple UGVs. The project leverages new image processing algorithms for monocular visual servoing and odometry to yield a unique, high-performance fused navigation system. Human Computer Interface (HCI) techniques from the entertainment software industry are being used to develop video-game style interfaces that require little training and build upon the navigation capabilities. By combining an advanced navigation system with an intuitive interface, a semi-autonomous control and navigation system is being created that is robust, user friendly, and less burdensome than many current generation systems. mand).

Design of a box trainer for objective assessment of technical skills in single-port surgery

NARCIS (Netherlands)

Horeman, Tim; Sun, Siyu; Tuijthof, Gabrielle J. M.; Jansen, Frank William; Meijerink, Jeroen W. J. H. J.; Dankelman, Jenny

2015-01-01

Laparoscopic single-port (SP) surgery uses only a single entry point for all instruments. The approach of SP has been applied in multiple laparoscopic disciplines owing to its improved cosmetic result. However, in SP surgery, instrument movements are further restricted, resulting in increased

EVALUATION OF METHODS FOR COREGISTRATION AND FUSION OF RPAS-BASED 3D POINT CLOUDS AND THERMAL INFRARED IMAGES

Directory of Open Access Journals (Sweden)

L. Hoegner

2016-06-01

Full Text Available This paper discusses the automatic coregistration and fusion of 3d point clouds generated from aerial image sequences and corresponding thermal infrared (TIR images. Both RGB and TIR images have been taken from a RPAS platform with a predefined flight path where every RGB image has a corresponding TIR image taken from the same position and with the same orientation with respect to the accuracy of the RPAS system and the inertial measurement unit. To remove remaining differences in the exterior orientation, different strategies for coregistering RGB and TIR images are discussed: (i coregistration based on 2D line segments for every single TIR image and the corresponding RGB image. This method implies a mainly planar scene to avoid mismatches; (ii coregistration of both the dense 3D point clouds from RGB images and from TIR images by coregistering 2D image projections of both point clouds; (iii coregistration based on 2D line segments in every single TIR image and 3D line segments extracted from intersections of planes fitted in the segmented dense 3D point cloud; (iv coregistration of both the dense 3D point clouds from RGB images and from TIR images using both ICP and an adapted version based on corresponding segmented planes; (v coregistration of both image sets based on point features. The quality is measured by comparing the differences of the back projection of homologous points in both corrected RGB and TIR images.

Existing sustainable renovation concepts for single-family houses

DEFF Research Database (Denmark)

Tommerup, Henrik M.; Vanhoutteghem, Lies; Svendsen, Svend

2010-01-01

In the Nordic Innovation Centre Project, SuccessFamilies, the main objective is to change the business environment in order to speed up the implementation of sustainable renovation of single-family houses – proposing new service concepts that will combine both the technical solutions, financing...... with individual solutions, traditional warehouses ”do-it-yourself-shops” and some actors marketing single products. To speed up the implementation of sustainable renovation of single-family houses there is a great need for full-service packages. Existing technical renovation concepts, typically focusing...... services as well as other promoting issues to overcome the behavioural, organizational, legal and social barriers that exist in sustainable renovation. A starting point for such a change has been to get an overview of the existing sustainable renovation concepts, i.e. full-service concepts and technical...

On two-point boundary correlations in the six-vertex model with domain wall boundary conditions

Science.gov (United States)

Colomo, F.; Pronko, A. G.

2005-05-01

The six-vertex model with domain wall boundary conditions on an N × N square lattice is considered. The two-point correlation function describing the probability of having two vertices in a given state at opposite (top and bottom) boundaries of the lattice is calculated. It is shown that this two-point boundary correlator is expressible in a very simple way in terms of the one-point boundary correlators of the model on N × N and (N - 1) × (N - 1) lattices. In alternating sign matrix (ASM) language this result implies that the doubly refined x-enumerations of ASMs are just appropriate combinations of the singly refined ones.

Registration of vehicle based panoramic image and LiDAR point cloud

Science.gov (United States)

Chen, Changjun; Cao, Liang; Xie, Hong; Zhuo, Xiangyu

2013-10-01

Higher quality surface information would be got when data from optical images and LiDAR were integrated, owing to the fact that optical images and LiDAR point cloud have unique characteristics that make them preferable in many applications. While most previous works focus on registration of pinhole perspective cameras to 2D or 3D LiDAR data. In this paper, a method for the registration of vehicle based panoramic image and LiDAR point cloud is proposed. Using the translation among panoramic image, single CCD image, laser scanner and Position and Orientation System (POS) along with the GPS/IMU data, precise co-registration between the panoramic image and the LiDAR point cloud in the world system is achieved. Results are presented under a real world data set collected by a new developed Mobile Mapping System (MMS) integrated with a high resolution panoramic camera, two laser scanners and a POS.

Detecting Stems in Dense and Homogeneous Forest Using Single-Scan TLS

Directory of Open Access Journals (Sweden)

Shaobo Xia

2015-10-01

Full Text Available Stem characteristics of plants are of great importance to both ecology study and forest management. Terrestrial laser scanning (TLS may provide an effective way to characterize the fine-scale structures of vegetation. However, clumping plants, dense foliage and thin structure could intensify the shadowing effect and pose a series of problems in identifying stems, distinguishing neighboring stems, and merging disconnected stem parts in point clouds. This paper presents a new method to automatically detect stems in dense and homogeneous forest using single-scan TLS data. Stem points are first identified with a two-scale classification method. Then a clustering approach is used to group the candidate stem points. Finally, a direction-growing algorithm based on a simple stem curve model is applied to merge stem points. Field experiments were carried out in two different bamboo plots with a stem density of about 7500 stems/ha. Overall accuracy of the stem detection is 88% and the quality of detected stems is mainly affected by the shadowing effect. Results indicate that the proposed method is feasible and effective in detection of bamboo stems using TLS data, and can be applied to other species of single-stem plants in dense forests.

Enhancing the accuracy of GPS point positioning by converting the single frequency data to dual frequency data

Directory of Open Access Journals (Sweden)

Aly M. El-naggar

2011-09-01

Full Text Available The global positioning system (GPS has been used to support a wide variety of applications, such as high-accuracy positioning and navigation. Differential GPS techniques can largely eliminate common-mode errors between the reference and the rover GPS stations resulting from ionospheric and tropospheric refraction and delays, satellite and receiver clock biases, and orbital errors [1]. The ionospheric delay in the propagation of global positioning system (GPS signals is one of the main sources of error in GPS precise positioning and navigation. A dual-frequency GPS receiver can eliminate (to the first order the ionospheric delay through a linear combination of the L1 and L2 observations [2]. The most significant effect of ionospheric delay appear in case of using single frequency data. In this paper the single frequency data of concerned station are converted to dual frequency data by employing dual frequency data from 11 regional GPS stations distributed around it. Total electron content (TEC was calculated at every GPS station to produce the mathematical model of TEC which is a function of latitude (Φ and longitude (λ. By using this mathematical model the values of TEC and L2 can be predicted at the single frequency GPS station for each satellite, after that the comparison between predicted and observation values of TEC and L2 was performed. The estimation method and test results of the proposed method indicates that the difference between predicted and observation values is very small.

Parametric Human Body Reconstruction Based on Sparse Key Points.

Science.gov (United States)

Cheng, Ke-Li; Tong, Ruo-Feng; Tang, Min; Qian, Jing-Ye; Sarkis, Michel

2016-11-01

We propose an automatic parametric human body reconstruction algorithm which can efficiently construct a model using a single Kinect sensor. A user needs to stand still in front of the sensor for a couple of seconds to measure the range data. The user's body shape and pose will then be automatically constructed in several seconds. Traditional methods optimize dense correspondences between range data and meshes. In contrast, our proposed scheme relies on sparse key points for the reconstruction. It employs regression to find the corresponding key points between the scanned range data and some annotated training data. We design two kinds of feature descriptors as well as corresponding regression stages to make the regression robust and accurate. Our scheme follows with dense refinement where a pre-factorization method is applied to improve the computational efficiency. Compared with other methods, our scheme achieves similar reconstruction accuracy but significantly reduces runtime.

Fully Convolutional Networks for Ground Classification from LIDAR Point Clouds

Science.gov (United States)

Rizaldy, A.; Persello, C.; Gevaert, C. M.; Oude Elberink, S. J.

2018-05-01

Deep Learning has been massively used for image classification in recent years. The use of deep learning for ground classification from LIDAR point clouds has also been recently studied. However, point clouds need to be converted into an image in order to use Convolutional Neural Networks (CNNs). In state-of-the-art techniques, this conversion is slow because each point is converted into a separate image. This approach leads to highly redundant computation during conversion and classification. The goal of this study is to design a more efficient data conversion and ground classification. This goal is achieved by first converting the whole point cloud into a single image. The classification is then performed by a Fully Convolutional Network (FCN), a modified version of CNN designed for pixel-wise image classification. The proposed method is significantly faster than state-of-the-art techniques. On the ISPRS Filter Test dataset, it is 78 times faster for conversion and 16 times faster for classification. Our experimental analysis on the same dataset shows that the proposed method results in 5.22 % of total error, 4.10 % of type I error, and 15.07 % of type II error. Compared to the previous CNN-based technique and LAStools software, the proposed method reduces the total error and type I error (while type II error is slightly higher). The method was also tested on a very high point density LIDAR point clouds resulting in 4.02 % of total error, 2.15 % of type I error and 6.14 % of type II error.

Traumatic Fetal Intracranial Hemorrhage Suggested by Point-of-Care Ultrasound

Directory of Open Access Journals (Sweden)

Lei Wu

2018-01-01

Full Text Available While the use of ultrasound to diagnose a fetal intracranial hemorrhage in utero is not a new concept, the emphasis of point-of-care ultrasound (POCUS at the initial trauma presentation of the mother to evaluate for fetal injury is novel. A review of the literature failed to reveal a single case report wherein POCUS in the workup of a pregnant trauma patient led to the diagnosis of fetal intracranial hemorrhage. This is such a case.

On the point-source approximation of earthquake dynamics

Directory of Open Access Journals (Sweden)

Andrea Bizzarri

2014-06-01

Full Text Available The focus on the present study is on the point-source approximation of a seismic source. First, we compare the synthetic motions on the free surface resulting from different analytical evolutions of the seismic source (the Gabor signal (G, the Bouchon ramp (B, the Cotton and Campillo ramp (CC, the Yoffe function (Y and the Liu and Archuleta function (LA. Our numerical experiments indicate that the CC and the Y functions produce synthetics with larger oscillations and correspondingly they have a higher frequency content. Moreover, the CC and the Y functions tend to produce higher peaks in the ground velocity (roughly of a factor of two. We have also found that the falloff at high frequencies is quite different: it roughly follows ω−2 in the case of G and LA functions, it decays more faster than ω−2 for the B function, while it is slow than ω−1 for both the CC and the Y solutions. Then we perform a comparison of seismic waves resulting from 3-D extended ruptures (both supershear and subshear obeying to different governing laws against those from a single point-source having the same features. It is shown that the point-source models tend to overestimate the ground motions and that they completely miss the Mach fronts emerging from the supershear transition process. When we compare the extended fault solutions against a multiple point-sources model the agreement becomes more significant, although relevant discrepancies still persist. Our results confirm that, and more importantly quantify how, the point-source approximation is unable to adequately describe the radiation emitted during a real world earthquake, even in the most idealized case of planar fault with homogeneous properties and embedded in a homogeneous, perfectly elastic medium.

Non-Fermi Liquid Behavior in the Single-Impurity Mixed Valence Problem

Science.gov (United States)

Zhang, Guang-Ming; Su, Zhao-Bin; Yu, Lu

An effective Hamiltonian of the Anderson single-impurity model with finite-range Coulomb interactions is derived near a particular limit, which is analogous to the Toulouse limit of the ordinary Kondo problem, and the physical properties around the mixed valence quantum critical point are calculated. At this quantum critical point, the local moment is only partially quenched and X-ray edge singularities are exhibited. Around this point, a new type of non-Fermi liquid behavior is predicted with an extra specific heat Cimp ~ T1/4 + AT ln T and spin-susceptibility χimp ~T-3/4 + B ln T.

Single toxin dose-response models revisited

Energy Technology Data Exchange (ETDEWEB)

Demidenko, Eugene, E-mail: eugened@dartmouth.edu [Department of Biomedical Data Science, Geisel School of Medicine at Dartmouth, Hanover, NH03756 (United States); Glaholt, SP, E-mail: sglaholt@indiana.edu [Indiana University, School of Public & Environmental Affairs, Bloomington, IN47405 (United States); Department of Biological Sciences, Dartmouth College, Hanover, NH03755 (United States); Kyker-Snowman, E, E-mail: ek2002@wildcats.unh.edu [Department of Natural Resources and the Environment, University of New Hampshire, Durham, NH03824 (United States); Shaw, JR, E-mail: joeshaw@indiana.edu [Indiana University, School of Public & Environmental Affairs, Bloomington, IN47405 (United States); Chen, CY, E-mail: Celia.Y.Chen@dartmouth.edu [Department of Biological Sciences, Dartmouth College, Hanover, NH03755 (United States)

2017-01-01

The goal of this paper is to offer a rigorous analysis of the sigmoid shape single toxin dose-response relationship. The toxin efficacy function is introduced and four special points, including maximum toxin efficacy and inflection points, on the dose-response curve are defined. The special points define three phases of the toxin effect on mortality: (1) toxin concentrations smaller than the first inflection point or (2) larger then the second inflection point imply low mortality rate, and (3) concentrations between the first and the second inflection points imply high mortality rate. Probabilistic interpretation and mathematical analysis for each of the four models, Hill, logit, probit, and Weibull is provided. Two general model extensions are introduced: (1) the multi-target hit model that accounts for the existence of several vital receptors affected by the toxin, and (2) model with a nonzero mortality at zero concentration to account for natural mortality. Special attention is given to statistical estimation in the framework of the generalized linear model with the binomial dependent variable as the mortality count in each experiment, contrary to the widespread nonlinear regression treating the mortality rate as continuous variable. The models are illustrated using standard EPA Daphnia acute (48 h) toxicity tests with mortality as a function of NiCl or CuSO{sub 4} toxin. - Highlights: • The paper offers a rigorous study of a sigmoid dose-response relationship. • The concentration with highest mortality rate is rigorously defined. • A table with four special points for five morality curves is presented. • Two new sigmoid dose-response models have been introduced. • The generalized linear model is advocated for estimation of sigmoid dose-response relationship.

On-line single server dial-a-ride problems

NARCIS (Netherlands)

Feuerstein, E.; Stougie, L.

1998-01-01

In this paper results on the dial-a-ride problem with a single server are presented. Requests for rides consist of two points in a metric space, a source and a destination. A ride has to be made by the server from the source to the destination. The server travels at unit speed in the metric space

Invariance for Single Curved Manifold

KAUST Repository

Castro, Pedro Machado Manhaes de

2012-01-01

Recently, it has been shown that, for Lambert illumination model, solely scenes composed by developable objects with a very particular albedo distribution produce an (2D) image with isolines that are (almost) invariant to light direction change. In this work, we provide and investigate a more general framework, and we show that, in general, the requirement for such in variances is quite strong, and is related to the differential geometry of the objects. More precisely, it is proved that single curved manifolds, i.e., manifolds such that at each point there is at most one principal curvature direction, produce invariant is surfaces for a certain relevant family of energy functions. In the three-dimensional case, the associated energy function corresponds to the classical Lambert illumination model with albedo. This result is also extended for finite-dimensional scenes composed by single curved objects. © 2012 IEEE.

Invariance for Single Curved Manifold

KAUST Repository

Castro, Pedro Machado Manhaes de

2012-08-01

Recently, it has been shown that, for Lambert illumination model, solely scenes composed by developable objects with a very particular albedo distribution produce an (2D) image with isolines that are (almost) invariant to light direction change. In this work, we provide and investigate a more general framework, and we show that, in general, the requirement for such in variances is quite strong, and is related to the differential geometry of the objects. More precisely, it is proved that single curved manifolds, i.e., manifolds such that at each point there is at most one principal curvature direction, produce invariant is surfaces for a certain relevant family of energy functions. In the three-dimensional case, the associated energy function corresponds to the classical Lambert illumination model with albedo. This result is also extended for finite-dimensional scenes composed by single curved objects. © 2012 IEEE.

Face landmark point tracking using LK pyramid optical flow

Science.gov (United States)

Zhang, Gang; Tang, Sikan; Li, Jiaquan

2018-04-01

LK pyramid optical flow is an effective method to implement object tracking in a video. It is used for face landmark point tracking in a video in the paper. The landmark points, i.e. outer corner of left eye, inner corner of left eye, inner corner of right eye, outer corner of right eye, tip of a nose, left corner of mouth, right corner of mouth, are considered. It is in the first frame that the landmark points are marked by hand. For subsequent frames, performance of tracking is analyzed. Two kinds of conditions are considered, i.e. single factors such as normalized case, pose variation and slowly moving, expression variation, illumination variation, occlusion, front face and rapidly moving, pose face and rapidly moving, and combination of the factors such as pose and illumination variation, pose and expression variation, pose variation and occlusion, illumination and expression variation, expression variation and occlusion. Global measures and local ones are introduced to evaluate performance of tracking under different factors or combination of the factors. The global measures contain the number of images aligned successfully, average alignment error, the number of images aligned before failure, and the local ones contain the number of images aligned successfully for components of a face, average alignment error for the components. To testify performance of tracking for face landmark points under different cases, tests are carried out for image sequences gathered by us. Results show that the LK pyramid optical flow method can implement face landmark point tracking under normalized case, expression variation, illumination variation which does not affect facial details, pose variation, and that different factors or combination of the factors have different effect on performance of alignment for different landmark points.

Production of Low-Freezing-Point Highly Branched Alkanes through Michael Addition.

Science.gov (United States)

Jing, Yaxuan; Xia, Qineng; Liu, Xiaohui; Wang, Yanqin

2017-12-22

A new approach for the production of low-freezing-point, high-quality fuels from lignocellulose-derived molecules was developed with Michael addition as the key step. Among the investigated catalysts, CoCl 2 ⋅6 H 2 O was found most active for the Michael addition of 2,4-pentanedione with FA (single aldol adduct of furfural and acetone, 4-(2-furanyl)-3-butene-2-one). Over CoCl 2 ⋅6 H 2 O, a high carbon yield of C 13 oxygenates (about 75 %) can be achieved under mild conditions (353 K, 20 h). After hydrodeoxygenation, low-freezing-point (hydrodeoxygenation, high density (0.8415 g mL -1 ) and low-freezing-point (<223 K) branched alkanes with 18, 23 carbons within lubricant range were also obtained over a Pd/NbOPO 4 catalyst. These highly branched alkanes can be directly used as transportation fuels or additives. This work opens a new strategy for the synthesis of highly branched alkanes with low freezing point from renewable biomass. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Conductance histogram evolution of an EC-MCBJ fabricated Au atomic point contact

Energy Technology Data Exchange (ETDEWEB)

Yang Yang; Liu Junyang; Chen Zhaobin; Tian Jinghua; Jin Xi; Liu Bo; Yang Fangzu; Tian Zhongqun [State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Li Xiulan; Tao Nongjian [Center for Bioelectronics and Biosensors, Biodesign Institute, Department of Electrical Engineering, Arizona State University, Tempe, AZ 85287-6206 (United States); Luo Zhongzi; Lu Miao, E-mail: zqtian@xmu.edu.cn [Micro-Electro-Mechanical Systems Research Center, Pen-Tung Sah Micro-Nano Technology Institute, Xiamen University, Xiamen 361005 (China)

2011-07-08

This work presents a study of Au conductance quantization based on a combined electrochemical deposition and mechanically controllable break junction (MCBJ) method. We describe the microfabrication process and discuss improved features of our microchip structure compared to the previous one. The improved structure prolongs the available life of the microchip and also increases the success rate of the MCBJ experiment. Stepwise changes in the current were observed at the last stage of atomic point contact breakdown and conductance histograms were constructed. The evolution of 1G{sub 0} peak height in conductance histograms was used to investigate the probability of formation of an atomic point contact. It has been shown that the success rate in forming an atomic point contact can be improved by decreasing the stretching speed and the degree that the two electrodes are brought into contact. The repeated breakdown and formation over thousands of cycles led to a distinctive increase of 1G{sub 0} peak height in the conductance histograms, and this increased probability of forming a single atomic point contact is discussed.

Conductance histogram evolution of an EC-MCBJ fabricated Au atomic point contact

International Nuclear Information System (INIS)

Yang Yang; Liu Junyang; Chen Zhaobin; Tian Jinghua; Jin Xi; Liu Bo; Yang Fangzu; Tian Zhongqun; Li Xiulan; Tao Nongjian; Luo Zhongzi; Lu Miao

2011-01-01

This work presents a study of Au conductance quantization based on a combined electrochemical deposition and mechanically controllable break junction (MCBJ) method. We describe the microfabrication process and discuss improved features of our microchip structure compared to the previous one. The improved structure prolongs the available life of the microchip and also increases the success rate of the MCBJ experiment. Stepwise changes in the current were observed at the last stage of atomic point contact breakdown and conductance histograms were constructed. The evolution of 1G 0 peak height in conductance histograms was used to investigate the probability of formation of an atomic point contact. It has been shown that the success rate in forming an atomic point contact can be improved by decreasing the stretching speed and the degree that the two electrodes are brought into contact. The repeated breakdown and formation over thousands of cycles led to a distinctive increase of 1G 0 peak height in the conductance histograms, and this increased probability of forming a single atomic point contact is discussed.

Fast measurement of luminosity at LEP by detecting the single bremsstrahlung photons

International Nuclear Information System (INIS)

Bini, C.; De Zorzi, G.; Diambrini Palazzi, G.; Di Cosimo, G.; Di Domenico, A.; Gauzzi, P.; Zanello, D.

1991-01-01

Luminosity and beam angular divergence have been measured at LEP with a fast monitor based on the single bremsstrahlung process e + e - → e + e - γ. The photons emitted at the interaction point 1 are detected by an electromagnetic calorimeter: both the photon energy and the impact point are measured. The beam angular divergence and the luminosity are determined in few minutes with a statistical error of 1%. With the present experimental layout the systematic error is of few percent; it would be reduced by performing the measurement on an experimental interaction point. (orig.)

Touch sensitivity with sterile standard surgical gloves and single-use protective gloves.

Science.gov (United States)

Tiefenthaler, W; Gimpl, S; Wechselberger, G; Benzer, A

2006-10-01

The purpose of this study was to evaluate touch sensitivity and static two-point discrimination of the dominant index and middle finger in 20 anaesthetists wearing no gloves, single-use protective gloves or sterile standard surgical gloves. Semmes-Weinstein filaments were used to measure cutaneous pressure thresholds, and a Two-Point-Discriminator to estimate static two-point discrimination. Wearing gloves significantly reduced touch sensitivity (p gloves. The results of our study suggest that the additional cost of sterile standard surgical gloves can not be justified in terms of touch sensitivity.

ERROR DISTRIBUTION EVALUATION OF THE THIRD VANISHING POINT BASED ON RANDOM STATISTICAL SIMULATION

Directory of Open Access Journals (Sweden)

C. Li

2012-07-01

Full Text Available POS, integrated by GPS / INS (Inertial Navigation Systems, has allowed rapid and accurate determination of position and attitude of remote sensing equipment for MMS (Mobile Mapping Systems. However, not only does INS have system error, but also it is very expensive. Therefore, in this paper error distributions of vanishing points are studied and tested in order to substitute INS for MMS in some special land-based scene, such as ground façade where usually only two vanishing points can be detected. Thus, the traditional calibration approach based on three orthogonal vanishing points is being challenged. In this article, firstly, the line clusters, which parallel to each others in object space and correspond to the vanishing points, are detected based on RANSAC (Random Sample Consensus and parallelism geometric constraint. Secondly, condition adjustment with parameters is utilized to estimate nonlinear error equations of two vanishing points (VX, VY. How to set initial weights for the adjustment solution of single image vanishing points is presented. Solving vanishing points and estimating their error distributions base on iteration method with variable weights, co-factor matrix and error ellipse theory. Thirdly, under the condition of known error ellipses of two vanishing points (VX, VY and on the basis of the triangle geometric relationship of three vanishing points, the error distribution of the third vanishing point (VZ is calculated and evaluated by random statistical simulation with ignoring camera distortion. Moreover, Monte Carlo methods utilized for random statistical estimation are presented. Finally, experimental results of vanishing points coordinate and their error distributions are shown and analyzed.

Error Distribution Evaluation of the Third Vanishing Point Based on Random Statistical Simulation

Science.gov (United States)

Li, C.

2012-07-01

POS, integrated by GPS / INS (Inertial Navigation Systems), has allowed rapid and accurate determination of position and attitude of remote sensing equipment for MMS (Mobile Mapping Systems). However, not only does INS have system error, but also it is very expensive. Therefore, in this paper error distributions of vanishing points are studied and tested in order to substitute INS for MMS in some special land-based scene, such as ground façade where usually only two vanishing points can be detected. Thus, the traditional calibration approach based on three orthogonal vanishing points is being challenged. In this article, firstly, the line clusters, which parallel to each others in object space and correspond to the vanishing points, are detected based on RANSAC (Random Sample Consensus) and parallelism geometric constraint. Secondly, condition adjustment with parameters is utilized to estimate nonlinear error equations of two vanishing points (VX, VY). How to set initial weights for the adjustment solution of single image vanishing points is presented. Solving vanishing points and estimating their error distributions base on iteration method with variable weights, co-factor matrix and error ellipse theory. Thirdly, under the condition of known error ellipses of two vanishing points (VX, VY) and on the basis of the triangle geometric relationship of three vanishing points, the error distribution of the third vanishing point (VZ) is calculated and evaluated by random statistical simulation with ignoring camera distortion. Moreover, Monte Carlo methods utilized for random statistical estimation are presented. Finally, experimental results of vanishing points coordinate and their error distributions are shown and analyzed.

Microfluidic Impedance Flow Cytometry Enabling High-Throughput Single-Cell Electrical Property Characterization

Science.gov (United States)

Chen, Jian; Xue, Chengcheng; Zhao, Yang; Chen, Deyong; Wu, Min-Hsien; Wang, Junbo

2015-01-01

This article reviews recent developments in microfluidic impedance flow cytometry for high-throughput electrical property characterization of single cells. Four major perspectives of microfluidic impedance flow cytometry for single-cell characterization are included in this review: (1) early developments of microfluidic impedance flow cytometry for single-cell electrical property characterization; (2) microfluidic impedance flow cytometry with enhanced sensitivity; (3) microfluidic impedance and optical flow cytometry for single-cell analysis and (4) integrated point of care system based on microfluidic impedance flow cytometry. We examine the advantages and limitations of each technique and discuss future research opportunities from the perspectives of both technical innovation and clinical applications. PMID:25938973

Bifurcations and degenerate periodic points in a three dimensional chaotic fluid flow

International Nuclear Information System (INIS)

Smith, L. D.; Rudman, M.; Lester, D. R.; Metcalfe, G.

2016-01-01

Analysis of the periodic points of a conservative periodic dynamical system uncovers the basic kinematic structure of the transport dynamics and identifies regions of local stability or chaos. While elliptic and hyperbolic points typically govern such behaviour in 3D systems, degenerate (parabolic) points also play an important role. These points represent a bifurcation in local stability and Lagrangian topology. In this study, we consider the ramifications of the two types of degenerate periodic points that occur in a model 3D fluid flow. (1) Period-tripling bifurcations occur when the local rotation angle associated with elliptic points is reversed, creating a reversal in the orientation of associated Lagrangian structures. Even though a single unstable point is created, the bifurcation in local stability has a large influence on local transport and the global arrangement of manifolds as the unstable degenerate point has three stable and three unstable directions, similar to hyperbolic points, and occurs at the intersection of three hyperbolic periodic lines. The presence of period-tripling bifurcation points indicates regions of both chaos and confinement, with the extent of each depending on the nature of the associated manifold intersections. (2) The second type of bifurcation occurs when periodic lines become tangent to local or global invariant surfaces. This bifurcation creates both saddle–centre bifurcations which can create both chaotic and stable regions, and period-doubling bifurcations which are a common route to chaos in 2D systems. We provide conditions for the occurrence of these tangent bifurcations in 3D conservative systems, as well as constraints on the possible types of tangent bifurcation that can occur based on topological considerations.

Localization and force analysis at the single virus particle level using atomic force microscopy

Energy Technology Data Exchange (ETDEWEB)

Liu, Chih-Hao [Institute of Applied Mechanics, Nation Taiwan University, Roosevelt Road, Taipei 10617, Taiwan (China); Horng, Jim-Tong [Department of Biochemistry, Chang Gung University, 259 Wen-Hwa First Road, Kweishan, Taoyuan 333, Taiwan (China); Chang, Jeng-Shian [Institute of Applied Mechanics, Nation Taiwan University, Roosevelt Road, Taipei 10617, Taiwan (China); Hsieh, Chung-Fan [Graduate Institute of Biomedical Sciences, Chang Gung University, Kweishan, Taoyuan 333, Taiwan (China); Tseng, You-Chen [Institute of Applied Mechanics, Nation Taiwan University, Roosevelt Road, Taipei 10617, Taiwan (China); Lin, Shiming, E-mail: til@ntu.edu.tw [Institute of Applied Mechanics, Nation Taiwan University, Roosevelt Road, Taipei 10617, Taiwan (China); Center for Optoelectronic Biomedicine, College of Medicine, Nation Taiwan University, 1-1 Jen-Ai Road, Taipei 10051, Taiwan (China)

2012-01-06

Highlights: Black-Right-Pointing-Pointer Localization of single virus particle. Black-Right-Pointing-Pointer Force measurements. Black-Right-Pointing-Pointer Force mapping. -- Abstract: Atomic force microscopy (AFM) is a vital instrument in nanobiotechnology. In this study, we developed a method that enables AFM to simultaneously measure specific unbinding force and map the viral glycoprotein at the single virus particle level. The average diameter of virus particles from AFM images and the specificity between the viral surface antigen and antibody probe were integrated to design a three-stage method that sets the measuring area to a single virus particle before obtaining the force measurements, where the influenza virus was used as the object of measurements. Based on the purposed method and performed analysis, several findings can be derived from the results. The mean unbinding force of a single virus particle can be quantified, and no significant difference exists in this value among virus particles. Furthermore, the repeatability of the proposed method is demonstrated. The force mapping images reveal that the distributions of surface viral antigens recognized by antibody probe were dispersed on the whole surface of individual virus particles under the proposed method and experimental criteria; meanwhile, the binding probabilities are similar among particles. This approach can be easily applied to most AFM systems without specific components or configurations. These results help understand the force-based analysis at the single virus particle level, and therefore, can reinforce the capability of AFM to investigate a specific type of viral surface protein and its distributions.

Evaluating gaze-based interface tools to facilitate point-and-select tasks with small targets

DEFF Research Database (Denmark)

Skovsgaard, Henrik; Mateo, Julio C.; Hansen, John Paulin

2011-01-01

-and-select tasks. We conducted two experiments comparing the performance of dwell, magnification and zoom methods in point-and-select tasks with small targets in single- and multiple-target layouts. Both magnification and zoom showed higher hit rates than dwell. Hit rates were higher when using magnification than...

Nanolithography based contacting method for electrical measurements on single template synthesized nanowires

DEFF Research Database (Denmark)

Fusil, S.; Piraux, L.; Mátéfi-Tempfli, Stefan

2005-01-01

A reliable method enabling electrical measurements on single nanowires prepared by electrodeposition in an alumina template is described. This technique is based on electrically controlled nanoindentation of a thin insulating resist deposited on the top face of the template filled by the nanowires....... We show that this method is very flexible, allowing us to electrically address single nanowires of controlled length down to 100 nm and of desired composition. Using this approach, current densities as large as 10 A cm were successfully injected through a point contact on a single magnetic...

Accuracy assessment of minimum control points for UAV photography and georeferencing

Science.gov (United States)

Skarlatos, D.; Procopiou, E.; Stavrou, G.; Gregoriou, M.

2013-08-01

In recent years, Autonomous Unmanned Aerial Vehicles (AUAV) became popular among researchers across disciplines because they combine many advantages. One major application is monitoring and mapping. Their ability to fly beyond eye sight autonomously, collecting data over large areas whenever, wherever, makes them excellent platform for monitoring hazardous areas or disasters. In both cases rapid mapping is needed while human access isn't always a given. Indeed, current automatic processing of aerial photos using photogrammetry and computer vision algorithms allows for rapid orthophomap production and Digital Surface Model (DSM) generation, as tools for monitoring and damage assessment. In such cases, control point measurement using GPS is either impossible, or time consuming or costly. This work investigates accuracies that can be attained using few or none control points over areas of one square kilometer, in two test sites; a typical block and a corridor survey. On board GPS data logged during AUAV's flight are being used for direct georeferencing, while ground check points are being used for evaluation. In addition various control point layouts are being tested using bundle adjustment for accuracy evaluation. Results indicate that it is possible to use on board single frequency GPS for direct georeferencing in cases of disaster management or areas without easy access, or even over featureless areas. Due to large numbers of tie points in the bundle adjustment, horizontal accuracy can be fulfilled with a rather small number of control points, but vertical accuracy may not.

Evaluation of single-walled carbon nanohorns as sorbent in dispersive micro solid-phase extraction

Energy Technology Data Exchange (ETDEWEB)

Jimenez-Soto, Juan Manuel; Cardenas, Soledad [Department of Analytical Chemistry, Institute of Fine Chemistry and Nanochemistry, Marie Curie Building, Campus de Rabanales, University of Cordoba, 14071 Cordoba (Spain); Valcarcel, Miguel, E-mail: qa1meobj@uco.es [Department of Analytical Chemistry, Institute of Fine Chemistry and Nanochemistry, Marie Curie Building, Campus de Rabanales, University of Cordoba, 14071 Cordoba (Spain)

2012-02-10

Highlights: Black-Right-Pointing-Pointer The potential of single walled carbon nanohorns in dispersive solid phase microextraction has been evaluated. Black-Right-Pointing-Pointer The method was characterized for the extraction of PAHs from waters. Black-Right-Pointing-Pointer Single walled carbon nanohorns were better extractant than carbon nanotubes and carbon nanocones. Black-Right-Pointing-Pointer The limits of detection were adequate for the target analytes in environmental waters. - Abstract: A new dispersive micro solid-phase extraction method which uses single-walled carbon nanohorns (SWNHs) as sorbent is proposed. The procedure combines the excellent sorbent properties of the nanoparticles with the efficiency of the dispersion of the material in the sample matrix. Under these conditions, the interaction with the analytes is maximized. The determination of polycyclic aromatic hydrocarbons was selected as model analytical problem. Two dispersion strategies were evaluated, being the functionalization via microwave irradiation better than the use of a surfactant. The extraction was accomplished by adding 1 mL of oxidized SWHNs (o-SWNHs) dispersion to 10 mL of water sample. After extraction, the mixture was passed through a disposable Nylon filter were the nanoparticles enriched with the PAHs were retained. The elution was carried out with 100 {mu}L of hexane. The limits of detection achieved were between 30 and 60 ng L{sup -1} with a precision (as repeatability) better than 12.5%. The recoveries obtained for the analytes in three different water samples were acceptable in all instances. The performance of o-SWNHs was favourably compared with that provided by carboxylated single-walled carbon nanotubes and thermally treated carbon nanocones.

Potential use of point shear wave elastography for the pancreas: A single center prospective study

International Nuclear Information System (INIS)

Kawada, Natsuko; Tanaka, Sachiko; Uehara, Hiroyuki; Ohkawa, Kazuyoshi; Yamai, Takuo; Takada, Ryoji; Shiroeda, Hisakazu; Arisawa, Tomiyasu; Tomita, Yasuhiko

2014-01-01

Aim: Clinical use of point shear wave elastography for the liver has been established, however, few studies demonstrated its usefulness for the pancreas. A prospective study was conducted to clarify its feasibility for the pancreas and its usefulness for the identification of high risk group for pancreatic cancer. Patients and methods: Consecutive eighty-five patients underwent point shear wave elastography for the pancreas. The success rate of shear wave velocity (SWV) measurement, that is the number of successful measurements over total 10 measurements, was recorded. The SWV of the pancreas measured at non-tumorous area was compared between patients with and without pancreatic cancer. Factors associated with high SWV were determined by logistic regression model. Results: Sixty patients were included, of these 18 had pancreatic cancer. The success rate of 100% was achieved at the head, the body and the tail of the pancreas in 80%, 83%, and 68% of the patients, respectively. The success rate of ≥80% was achieved in 100%, 100%, and 96% of the patients, respectively. Although mean SWV of the pancreas harboring pancreatic cancer tended to be higher compared with that of the pancreas without cancer (1.51 ± 0.45 m/s vs 1.43 ± 0.28 m/s), they did not reach statistical significance. Multivariate analysis showed that increased amount of alcohol intake was associated with high SWV. Conclusion: The SWV of the pancreas was measured with excellent success rate. However, tendency of higher SWV obtained from the pancreas harboring pancreatic cancer needed to be further investigated

Quantitative reconstruction from a single diffraction-enhanced image

International Nuclear Information System (INIS)

Paganin, D.M.; Lewis, R.A.; Kitchen, M.

2003-01-01

Full text: We develop an algorithm for using a single diffraction-enhanced image (DEI) to obtain a quantitative reconstruction of the projected thickness of a single-material sample which is embedded within a substrate of approximately constant thickness. This algorithm is used to quantitatively map inclusions in a breast phantom, from a single synchrotron DEI image. In particular, the reconstructed images quantitatively represent the projected thickness in the bulk of the sample, in contrast to DEI images which greatly emphasise sharp edges (high spatial frequencies). In the context of an ultimate aim of improved methods for breast cancer detection, the reconstructions are potentially of greater diagnostic value compared to the DEI data. Lastly, we point out that the methods of analysis presented here are also applicable to the quantitative analysis of differential interference contrast (DIC) images

Forced sound transmission through a finite-sized single leaf panel subject to a point source excitation.

Science.gov (United States)

Wang, Chong

2018-03-01

In the case of a point source in front of a panel, the wavefront of the incident wave is spherical. This paper discusses spherical sound waves transmitting through a finite sized panel. The forced sound transmission performance that predominates in the frequency range below the coincidence frequency is the focus. Given the point source located along the centerline of the panel, forced sound transmission coefficient is derived through introducing the sound radiation impedance for spherical incident waves. It is found that in addition to the panel mass, forced sound transmission loss also depends on the distance from the source to the panel as determined by the radiation impedance. Unlike the case of plane incident waves, sound transmission performance of a finite sized panel does not necessarily converge to that of an infinite panel, especially when the source is away from the panel. For practical applications, the normal incidence sound transmission loss expression of plane incident waves can be used if the distance between the source and panel d and the panel surface area S satisfy d/S>0.5. When d/S ≈0.1, the diffuse field sound transmission loss expression may be a good approximation. An empirical expression for d/S=0  is also given.

Laser stimulation of the acupoint 'Zusanli' (ST.36) on the ...

Indian Academy of Sciences (India)

2016-02-13

Feb 13, 2016 ... [Frederico ÉHFF, Santos AA, Sá-Caputo DC, Neves RF, Guimarães CAS, Chang5 S and Bernardo-Filho .... ST.36 of the stomach meridian (de Souza Franco et al. ..... S, Ailton Alexandre Santos AAV, Paoli S, Presta GA, et al.

eLISA Telescope In-field Pointing and Scattered Light Study

Science.gov (United States)

Livas, J.; Sankar, S.; West, G.; Seals, L.; Howard, J.; Fitzsimons, E.

2017-05-01

The orbital motion of the three spacecraft that make up the eLISA Observatory constellation causes long-arm line of sight variations of approximately ± one degree over the course of a year. The baseline solution is to package the telescope, the optical bench, and the gravitational reference sensor (GRS) into an optical assembly at each end of the measurement arm, and then to articulate the assembly. An optical phase reference is exchanged between the moving optical benches with a single mode optical fiber (“backlink” fiber). An alternative solution, referred to as in-field pointing, embeds a steering mirror into the optical design, fixing the optical benches and eliminating the backlink fiber, but requiring the additional complication of a two-stage optical design for the telescope. We examine the impact of an in-field pointing design on the scattered light performance.

Acceleration of Meshfree Radial Point Interpolation Method on Graphics Hardware

International Nuclear Information System (INIS)

Nakata, Susumu

2008-01-01

This article describes a parallel computational technique to accelerate radial point interpolation method (RPIM)-based meshfree method using graphics hardware. RPIM is one of the meshfree partial differential equation solvers that do not require the mesh structure of the analysis targets. In this paper, a technique for accelerating RPIM using graphics hardware is presented. In the method, the computation process is divided into small processes suitable for processing on the parallel architecture of the graphics hardware in a single instruction multiple data manner.

Mechanistic modelling of the drying behaviour of single pharmaceutical granules

DEFF Research Database (Denmark)

Thérèse F.C. Mortier, Séverine; Beer, Thomas De; Gernaey, Krist

2012-01-01

The trend to move towards continuous production processes in pharmaceutical applications enhances the necessity to develop mechanistic models to understand and control these processes. This work focuses on the drying behaviour of a single wet granule before tabletting, using a six...... phase (submodel 2), the water inside the granule evaporates. The second submodel contains an empirical power coefficient, b. A sensitivity analysis was performed to study the influence of parameters on the moisture content of single pharmaceutical granules, which clearly points towards the importance...

Hinkley Point 'C' power station public inquiry: proof of evidence on agriculture

International Nuclear Information System (INIS)

Worthington, T.R.

1988-09-01

A public inquiry has been set up to examine the planning application made by the Central Electricity Generating Board (CEGB) for the construction of a 1200 MW Pressurized Water Reactor power station at Hinkley Point (Hinkley Point ''C'') in the United Kingdom. Agricultural land will need to be acquired for the proposed construction both on a temporary and permanent basis. The CEGB evidence to the Inquiry identifies the land which will be permanently lost for agricultural purposes and that which could eventually be returned to agriculture. All the land required is on a single holding but should leave a viable area to be farmed. The farming business would be compensated for loss of profits. (UK)

Stability Analysis of Periodic Systems by Truncated Point Mappings

Science.gov (United States)

Guttalu, R. S.; Flashner, H.

1996-01-01

An approach is presented deriving analytical stability and bifurcation conditions for systems with periodically varying coefficients. The method is based on a point mapping(period to period mapping) representation of the system's dynamics. An algorithm is employed to obtain an analytical expression for the point mapping and its dependence on the system's parameters. The algorithm is devised to derive the coefficients of a multinominal expansion of the point mapping up to an arbitrary order in terms of the state variables and of the parameters. Analytical stability and bifurcation condition are then formulated and expressed as functional relations between the parameters. To demonstrate the application of the method, the parametric stability of Mathieu's equation and of a two-degree of freedom system are investigated. The results obtained by the proposed approach are compared to those obtained by perturbation analysis and by direct integration which we considered to the "exact solution". It is shown that, unlike perturbation analysis, the proposed method provides very accurate solution even for large valuesof the parameters. If an expansion of the point mapping in terms of a small parameter is performed the method is equivalent to perturbation analysis. Moreover, it is demonstrated that the method can be easily applied to multiple-degree-of-freedom systems using the same framework. This feature is an important advantage since most of the existing analysis methods apply mainly to single-degree-of-freedom systems and their extension to higher dimensions is difficult and computationally cumbersome.

The New LMK Primary Standard for Dew-Point Sensor Calibration: Evaluation of the High-Range Saturator Efficiency

Science.gov (United States)

Hudoklin, Domen; Drnovšek, Janko

2008-10-01

In the field of hygrometry, a primary dew-point standard can be realized according to several proven principles, such as single-pressure (1-P), two-pressure (2-P), or divided flow. Different realizations have been introduced by various national laboratories, each resulting in a stand-alone complex generation system. Recent trends in generator design favor the single-pressure principle without recirculation because it promises theoretically lower uncertainty and because it avoids problems regarding the leak tightness of the recirculation. Instead of recirculation, the efficiency of saturation, the key factor, is increased by preconditioning the inlet gas entering the saturator. For preconditioning, a presaturator or purifier is used to bring the dew point of the inlet stream close to the saturator temperature. The purpose of the paper is to identify the minimum requirements for the preconditioning system and the main saturator to assure efficient saturation for the LMK generator. Moreover, the aim is also to find out if the preconditioning system can be avoided despite the rather simple construction of the main saturator. If this proves to be the case, the generator design can be simplified while maintaining an accurate value of the generated dew point. Experiments were carried out within the scope of improving our existing primary generator in the above-ambient dew-point range up to +70°C. These results show the generated dew point is within the measurement uncertainty for any dew-point value of the inlet gas. Thus, the preconditioning subsystem can be avoided, which leads to a simplified generator design.

An introduction to single-user information theory

CERN Document Server

Alajaji, Fady

2018-01-01

This book presents a succinct and mathematically rigorous treatment of the main pillars of Shannon’s information theory, discussing the fundamental concepts and indispensable results of Shannon’s mathematical theory of communications. It includes five meticulously written core chapters (with accompanying problems), emphasizing the key topics of information measures; lossless and lossy data compression; channel coding; and joint source-channel coding for single-user (point-to-point) communications systems. It also features two appendices covering necessary background material in real analysis and in probability theory and stochastic processes. The book is ideal for a one-semester foundational course on information theory for senior undergraduate and entry-level graduate students in mathematics, statistics, engineering, and computing and information sciences. A comprehensive instructor’s solutions manual is available.

FULLY CONVOLUTIONAL NETWORKS FOR GROUND CLASSIFICATION FROM LIDAR POINT CLOUDS

Directory of Open Access Journals (Sweden)

A. Rizaldy

2018-05-01

Full Text Available Deep Learning has been massively used for image classification in recent years. The use of deep learning for ground classification from LIDAR point clouds has also been recently studied. However, point clouds need to be converted into an image in order to use Convolutional Neural Networks (CNNs. In state-of-the-art techniques, this conversion is slow because each point is converted into a separate image. This approach leads to highly redundant computation during conversion and classification. The goal of this study is to design a more efficient data conversion and ground classification. This goal is achieved by first converting the whole point cloud into a single image. The classification is then performed by a Fully Convolutional Network (FCN, a modified version of CNN designed for pixel-wise image classification. The proposed method is significantly faster than state-of-the-art techniques. On the ISPRS Filter Test dataset, it is 78 times faster for conversion and 16 times faster for classification. Our experimental analysis on the same dataset shows that the proposed method results in 5.22 % of total error, 4.10 % of type I error, and 15.07 % of type II error. Compared to the previous CNN-based technique and LAStools software, the proposed method reduces the total error and type I error (while type II error is slightly higher. The method was also tested on a very high point density LIDAR point clouds resulting in 4.02 % of total error, 2.15 % of type I error and 6.14 % of type II error.

Tipping Point

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Full Text Available ... OnSafety CPSC Stands for Safety The Tipping Point Home > 60 Seconds of Safety (Videos) > The Tipping Point ... 24 hours a day. For young children whose home is a playground, it’s the best way to ...

Interesting Interest Points

DEFF Research Database (Denmark)

Aanæs, Henrik; Dahl, Anders Lindbjerg; Pedersen, Kim Steenstrup

2012-01-01

on spatial invariance of interest points under changing acquisition parameters by measuring the spatial recall rate. The scope of this paper is to investigate the performance of a number of existing well-established interest point detection methods. Automatic performance evaluation of interest points is hard......Not all interest points are equally interesting. The most valuable interest points lead to optimal performance of the computer vision method in which they are employed. But a measure of this kind will be dependent on the chosen vision application. We propose a more general performance measure based...... position. The LED illumination provides the option for artificially relighting the scene from a range of light directions. This data set has given us the ability to systematically evaluate the performance of a number of interest point detectors. The highlights of the conclusions are that the fixed scale...

The timing of control signals underlying fast point-to-point arm movements.

Science.gov (United States)

Ghafouri, M; Feldman, A G

2001-04-01

It is known that proprioceptive feedback induces muscle activation when the facilitation of appropriate motoneurons exceeds their threshold. In the suprathreshold range, the muscle-reflex system produces torques depending on the position and velocity of the joint segment(s) that the muscle spans. The static component of the torque-position relationship is referred to as the invariant characteristic (IC). According to the equilibrium-point (EP) hypothesis, control systems produce movements by changing the activation thresholds and thus shifting the IC of the appropriate muscles in joint space. This control process upsets the balance between muscle and external torques at the initial limb configuration and, to regain the balance, the limb is forced to establish a new configuration or, if the movement is prevented, a new level of static torques. Taken together, the joint angles and the muscle torques generated at an equilibrium configuration define a single variable called the EP. Thus by shifting the IC, control systems reset the EP. Muscle activation and movement emerge following the EP resetting because of the natural physical tendency of the system to reach equilibrium. Empirical and simulation studies support the notion that the control IC shifts and the resulting EP shifts underlying fast point-to-point arm movements are gradual rather than step-like. However, controversies exist about the duration of these shifts. Some studies suggest that the IC shifts cease with the movement offset. Other studies propose that the IC shifts end early in comparison to the movement duration (approximately, at peak velocity). The purpose of this study was to evaluate the duration of the IC shifts underlying fast point-to-point arm movements. Subjects made fast (hand peak velocity about 1.3 m/s) planar arm movements toward different targets while grasping a handle. Hand forces applied to the handle and shoulder/elbow torques were, respectively, measured from a force sensor placed

Morphological Transition in the Cellular Structure of Single Crystals of Nickel-Tungsten Alloys near the Congruent Melting Point

International Nuclear Information System (INIS)

Azhazha, V.M.; Ladygin, A.N.; Sverdlov, V.Ja.; Zhemanyuk, P.D.; Klochikhin, V.V.

2005-01-01

The structure and microhardness of single crystals of nickel-tungsten alloys containing 25-36 wt % W are investigated. The temperature gradient at the crystallization front and the velocity of the crystallization front are the variable parameters of directional crystallization. It is found that, when the velocity of the crystallization front is 4 mm/min, the morphology of the cellular structure of the single crystals grown from nickel-tungsten alloys changes from square cells to hexagonal cells at a tungsten content of greater than or equal to 31 wt %. As the velocity of the crystallization front increases to 10 mm/min, no morphological transition occurs. It is shown that impurities play an important role in the formation of a cellular structure with cells of different types

Streak camera imaging of single photons at telecom wavelength

Science.gov (United States)

Allgaier, Markus; Ansari, Vahid; Eigner, Christof; Quiring, Viktor; Ricken, Raimund; Donohue, John Matthew; Czerniuk, Thomas; Aßmann, Marc; Bayer, Manfred; Brecht, Benjamin; Silberhorn, Christine

2018-01-01

Streak cameras are powerful tools for temporal characterization of ultrafast light pulses, even at the single-photon level. However, the low signal-to-noise ratio in the infrared range prevents measurements on weak light sources in the telecom regime. We present an approach to circumvent this problem, utilizing an up-conversion process in periodically poled waveguides in Lithium Niobate. We convert single photons from a parametric down-conversion source in order to reach the point of maximum detection efficiency of commercially available streak cameras. We explore phase-matching configurations to apply the up-conversion scheme in real-world applications.

A Marked Point Process Framework for Extracellular Electrical Potentials

Directory of Open Access Journals (Sweden)

Carlos A. Loza

2017-12-01

Full Text Available Neuromodulations are an important component of extracellular electrical potentials (EEP, such as the Electroencephalogram (EEG, Electrocorticogram (ECoG and Local Field Potentials (LFP. This spatially temporal organized multi-frequency transient (phasic activity reflects the multiscale spatiotemporal synchronization of neuronal populations in response to external stimuli or internal physiological processes. We propose a novel generative statistical model of a single EEP channel, where the collected signal is regarded as the noisy addition of reoccurring, multi-frequency phasic events over time. One of the main advantages of the proposed framework is the exceptional temporal resolution in the time location of the EEP phasic events, e.g., up to the sampling period utilized in the data collection. Therefore, this allows for the first time a description of neuromodulation in EEPs as a Marked Point Process (MPP, represented by their amplitude, center frequency, duration, and time of occurrence. The generative model for the multi-frequency phasic events exploits sparseness and involves a shift-invariant implementation of the clustering technique known as k-means. The cost function incorporates a robust estimation component based on correntropy to mitigate the outliers caused by the inherent noise in the EEP. Lastly, the background EEP activity is explicitly modeled as the non-sparse component of the collected signal to further improve the delineation of the multi-frequency phasic events in time. The framework is validated using two publicly available datasets: the DREAMS sleep spindles database and one of the Brain-Computer Interface (BCI competition datasets. The results achieve benchmark performance and provide novel quantitative descriptions based on power, event rates and timing in order to assess behavioral correlates beyond the classical power spectrum-based analysis. This opens the possibility for a unifying point process framework of

Modelling The Effect of Changing Point Systems to Teams’ Competition Standing in A Malaysian Soccer Super League

Science.gov (United States)

Mat Yusof, Muhammad; Khalid, Ruzelan; Hamid, Mohamad Shukri Abdul; Mansor, Rosnalini; Sulaiman, Tajularipin

2018-05-01

In a sports league such as in a soccer league, the teams’ competition standing is based on a cumulative point system. Typically, the standard point system is given to every single match for win, draw and lose teams is the 3-1-0 point system. In this paper, we explore the effect of changing point systems to teams’ competition standing by changing the weightage values for win, draw and lose teams. Three types of point systems are explored in our soccer simulation model; firstly the 3-1-0, secondly the 2-1-0 and thirdly the 4-1-0 point system. Based on the teams participating in a Malaysian soccer Super League, our simulation result shows that there are small changes in term of teams’ competition standing when we compared the actual rank and the simulation rank position. However, the 4-1-0 point system recorded the highest Pearson correlation value which is 0.97, followed by the 2-1-0 point system (0.95) and thirdly the 3-1-0 point system (0.94).

Zero-point oscillations, zero-point fluctuations, and fluctuations of zero-point oscillations

International Nuclear Information System (INIS)

Khalili, Farit Ya

2003-01-01

Several physical effects and methodological issues relating to the ground state of an oscillator are considered. Even in the simplest case of an ideal lossless harmonic oscillator, its ground state exhibits properties that are unusual from the classical point of view. In particular, the mean value of the product of two non-negative observables, kinetic and potential energies, is negative in the ground state. It is shown that semiclassical and rigorous quantum approaches yield substantially different results for the ground state energy fluctuations of an oscillator with finite losses. The dependence of zero-point fluctuations on the boundary conditions is considered. Using this dependence, it is possible to transmit information without emitting electromagnetic quanta. Fluctuations of electromagnetic pressure of zero-point oscillations are analyzed, and the corresponding mechanical friction is considered. This friction can be viewed as the most fundamental mechanism limiting the quality factor of mechanical oscillators. Observation of these effects exceeds the possibilities of contemporary experimental physics but almost undoubtedly will be possible in the near future. (methodological notes)

Point-point and point-line moving-window correlation spectroscopy and its applications

Science.gov (United States)

Zhou, Qun; Sun, Suqin; Zhan, Daqi; Yu, Zhiwu

2008-07-01

In this paper, we present a new extension of generalized two-dimensional (2D) correlation spectroscopy. Two new algorithms, namely point-point (P-P) correlation and point-line (P-L) correlation, have been introduced to do the moving-window 2D correlation (MW2D) analysis. The new method has been applied to a spectral model consisting of two different processes. The results indicate that P-P correlation spectroscopy can unveil the details and re-constitute the entire process, whilst the P-L can provide general feature of the concerned processes. Phase transition behavior of dimyristoylphosphotidylethanolamine (DMPE) has been studied using MW2D correlation spectroscopy. The newly proposed method verifies that the phase transition temperature is 56 °C, same as the result got from a differential scanning calorimeter. To illustrate the new method further, a lysine and lactose mixture has been studied under thermo perturbation. Using the P-P MW2D, the Maillard reaction of the mixture was clearly monitored, which has been very difficult using conventional display of FTIR spectra.

Tipping Point

Medline Plus

Full Text Available ... 60 Seconds of Safety (Videos) > The Tipping Point The Tipping Point by CPSC Blogger September 22, 2009 appliance child Childproofing CPSC danger death electrical fall furniture head injury product safety television tipover tv Watch the video in Adobe Flash ...

Poppy Crop Height and Capsule Volume Estimation from a Single UAS Flight

Directory of Open Access Journals (Sweden)

Faheem Iqbal

2017-06-01

Full Text Available The objective of this study was to estimate poppy plant height and capsule volume with remote sensing using an Unmanned Aircraft System (UAS. Data were obtained from field measurements and UAS flights over two poppy crops at Cambridge and Cressy in Tasmania. Imagery acquired from the UAS was used to produce dense point clouds using structure from motion (SfM and multi-view stereopsis (MVS techniques. Dense point clouds were used to generate a digital surface model (DSM and orthophoto mosaic. An RGB index was derived from the orthophoto to extract the bare ground spaces. This bare ground space mask was used to filter the points on the ground, and a digital terrain model (DTM was interpolated from these points. Plant height values were estimated by subtracting the DSM and DTM to generate a Crop Height Model (CHM. UAS-derived plant height (PH and field measured PH in Cambridge were strongly correlated with R2 values ranging from 0.93 to 0.97 for Transect 1 and Transect 2, respectively, while at Cressy results from a single flight provided R2 of 0.97. Therefore, the proposed method can be considered an important step towards crop surface model (CSM generation from a single UAS flight in situations where a bare ground DTM is unavailable. High correlations were found between UAS-derived PH and poppy capsule volume (CV at capsule formation stage (R2 0.74, with relative error of 19.62%. Results illustrate that plant height can be reliably estimated for poppy crops based on a single UAS flight and can be used to predict opium capsule volume at capsule formation stage.

The auriculotemporal nerve in etiology of migraine headaches: compression points and anatomical variations.

Science.gov (United States)

Chim, Harvey; Okada, Haruko C; Brown, Matthew S; Alleyne, Brendan; Liu, Mengyuan T; Zwiebel, Samantha; Guyuron, Bahman

2012-08-01

The auriculotemporal nerve has been identified as one of the peripheral trigger sites for migraine headaches. However, its distal course is poorly mapped following emergence from the parotid gland. In addition, a reliable anatomical landmark for locating the potential compression points along the course of the nerve during surgery has not been sufficiently described. Twenty hemifaces on 10 fresh cadavers were dissected to trace the course of the auriculotemporal nerve from the inferior border of the zygomatic arch to its termination in the temporal scalp. The compression points were mapped and the distances were measured from the most anterosuperior point of the external auditory meatus, which was used as a fixed anatomical landmark. Three potential compression points along the course of the auriculotemporal nerve were identified. Compression points 1 and 2 corresponded to preauricular fascial bands. Compression point 1 was centered 13.1±5.9 mm anterior and 5.0±7.0 mm superior to the most anterosuperior point of the external auditory meatus, whereas compression point 2 was centered at 11.9±6.0 mm anterior and 17.2±10.4 mm superior to the most anterosuperior point of the external auditory meatus. A significant relationship was found between the auriculotemporal nerve and superficial temporal artery (compression point 3) in 80 percent of hemifaces, with three patterns of interaction: a single site of artery crossing over the nerve (62.5 percent), a helical intertwining relationship (18.8 percent), and nerve crossing over the artery (18.8 percent). Findings from this cadaver study provide information relevant to the operative localization of potential compression points along the auriculotemporal nerve.

Habitat characteristics at den sites of the Point Arena mountain beaver (Aplodontia rufa nigra)

Science.gov (United States)

William J. Zielinski; John E. Hunter; Robin Hamlin; Keith M. Slauson; M. J. Mazurek

2010-01-01

The Point Arena mountain beaver (Aplodontia rufa nigra) is a federally listed endangered species, but has been the subject of few studies. Mountain beavers use burrows that include a single subterranean den. Foremost among the information needs for this subspecies is a description of the above-ground habitat features associated with dens. Using...

Heaving buoys, point absorbers and arrays.

Science.gov (United States)

Falnes, Johannes; Hals, Jørgen

2012-01-28

Absorption of wave energy may be considered as a phenomenon of interference between incident and radiated waves generated by an oscillating object; a wave-energy converter (WEC) that displaces water. If a WEC is very small in comparison with one wavelength, it is classified as a point absorber (PA); otherwise, as a 'quasi-point absorber'. The latter may be a dipole-mode radiator, for instance an immersed body oscillating in the surge mode or pitch mode, while a PA is so small that it should preferably be a source-mode radiator, for instance a heaving semi-submerged buoy. The power take-off capacity, the WEC's maximum swept volume and preferably also its full physical volume should be reasonably matched to the wave climate. To discuss this matter, two different upper bounds for absorbed power are applied in a 'Budal diagram'. It appears that, for a single WEC unit, a power capacity of only about 0.3 MW matches well to a typical offshore wave climate, and the full physical volume has, unfortunately, to be significantly larger than the swept volume, unless phase control is used. An example of a phase-controlled PA is presented. For a sizeable wave-power plant, an array consisting of hundreds, or even thousands, of mass-produced WEC units is required.

Electroacupuncture improves microcirculation and neuronal morphology in the spinal cord of a rat model of intervertebral disc extrusion

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Dai-xun Jiang

2015-01-01

Full Text Available Most studies on spinal cord neuronal injury have focused on spinal cord tissue histology and the expression of nerve cell damage and repair-related genes. The importance of the microcirculation is often ignored in spinal cord injury and repair research. Therefore, in this study, we established a rat model of intervertebral disc extrusion by inserting a silica gel pad into the left ventral surface of T 13 . Electroacupuncture was used to stimulate the bilateral Zusanli point (ST36 and Neiting point (ST44 for 14 days. Compared with control animals, blood flow in the first lumbar vertebra (L 1 was noticeably increased in rats given electroacupuncture. Microvessel density in the T 13 segment of the spinal cord was increased significantly as well. The number of normal neurons was higher in the ventral horn of the spinal cord. In addition, vacuolation in the white matter was lessened. No obvious glial cell proliferation was visible. Furthermore, hindlimb motor function was improved significantly. Collectively, our results suggest that electroacupuncture can improve neuronal morphology and microcirculation, and promote the recovery of neurological functions in a rat model of intervertebral disc extrusion.

Single point mutations distributed in 10 soluble and membrane regions of the Nicotiana plumbaginifolia plasma membrane PMA2 H+-ATPase activate the enzyme and modify the structure of the C-terminal region.

Science.gov (United States)

Morsomme, P; Dambly, S; Maudoux, O; Boutry, M

1998-12-25

The Nicotiana plumbaginifolia pma2 (plasma membrane H+-ATPase) gene is capable of functionally replacing the H+-ATPase genes of the yeast Saccharomyces cerevisiae, provided that the external pH is kept above 5.0. Single point mutations within the pma2 gene were previously identified that improved H+-ATPase activity and allowed yeast growth at pH 4.0. The aim of the present study was to identify most of the PMA2 positions, the mutation of which would lead to improved growth and to determine whether all these mutations result in similar enzymatic and structural modifications. We selected additional mutants in total 42 distinct point mutations localized in 30 codons. They were distributed in 10 soluble and membrane regions of the enzyme. Most mutant PMA2 H+-ATPases were characterized by a higher specific activity, lower inhibition by ADP, and lower stimulation by lysophosphatidylcholine than wild-type PMA2. The mutants thus seem to be constitutively activated. Partial tryptic digestion and immunodetection showed that the PMA2 mutants had a conformational change making the C-terminal region more accessible. These data therefore support the hypothesis that point mutations in various H+-ATPase parts displace the inhibitory C-terminal region, resulting in enzyme activation. The high density of mutations within the first half of the C-terminal region suggests that this part is involved in the interaction between the inhibitory C-terminal region and the rest of the enzyme.

Waveguides with Absorbing Boundaries: Nonlinearity Controlled by an Exceptional Point and Solitons

Science.gov (United States)

Midya, Bikashkali; Konotop, Vladimir V.

2017-07-01

We reveal the existence of continuous families of guided single-mode solitons in planar waveguides with weakly nonlinear active core and absorbing boundaries. Stable propagation of TE and TM-polarized solitons is accompanied by attenuation of all other modes, i.e., the waveguide features properties of conservative and dissipative systems. If the linear spectrum of the waveguide possesses exceptional points, which occurs in the case of TM polarization, an originally focusing (defocusing) material nonlinearity may become effectively defocusing (focusing). This occurs due to the geometric phase of the carried eigenmode when the surface impedance encircles the exceptional point. In its turn, the change of the effective nonlinearity ensures the existence of dark (bright) solitons in spite of focusing (defocusing) Kerr nonlinearity of the core. The existence of an exceptional point can also result in anomalous enhancement of the effective nonlinearity. In terms of practical applications, the nonlinearity of the reported waveguide can be manipulated by controlling the properties of the absorbing cladding.

CERN Proton Synchrotronworking point Matrix for extended pole face winding powering scheme

CERN Document Server

Freyermuth, P; Delrieux, M; Genoud, H; Gilardoni, S; Hanke, K; Hans, O; Mataguez, S; Metral, G; Peters, F; Steerenberg, R; Vandorpe, B

2010-01-01

The CERN Proton Synchrotron has been continuously improving its beam performances since 1959. The working point parameters of the accelerator are mainly controlled by dedicated windings installed on the poles of the main combined function magnets. In 2007, the power supplies of these windings were renovated and extended from three to five independent groups, allowing exploration of new working point settings. This configuration offers the flexibility of several adjustment strategies such as leaving one current free or to control an additional physical parameter, like Q′′ h. A non-linear chromaticity measurement campaign, at different beam momenta, resulted in matrices defining the relationship between the five pole face winding currents and the four beam parameters Qh, Qv, h, and v. Each cell of these matrices was fitted against momentum. The final result is a single matrix as a function of beam momentum, which is now used by the operational software to trim the working point. This paper summarises this m...

Ecosystem approach to fisheries: Exploring environmental and trophic effects on Maximum Sustainable Yield (MSY reference point estimates.

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Rajeev Kumar

Full Text Available We present a comprehensive analysis of estimation of fisheries Maximum Sustainable Yield (MSY reference points using an ecosystem model built for Mille Lacs Lake, the second largest lake within Minnesota, USA. Data from single-species modelling output, extensive annual sampling for species abundances, annual catch-survey, stomach-content analysis for predatory-prey interactions, and expert opinions were brought together within the framework of an Ecopath with Ecosim (EwE ecosystem model. An increase in the lake water temperature was observed in the last few decades; therefore, we also incorporated a temperature forcing function in the EwE model to capture the influences of changing temperature on the species composition and food web. The EwE model was fitted to abundance and catch time-series for the period 1985 to 2006. Using the ecosystem model, we estimated reference points for most of the fished species in the lake at single-species as well as ecosystem levels with and without considering the influence of temperature change; therefore, our analysis investigated the trophic and temperature effects on the reference points. The paper concludes that reference points such as MSY are not stationary, but change when (1 environmental conditions alter species productivity and (2 fishing on predators alters the compensatory response of their prey. Thus, it is necessary for the management to re-estimate or re-evaluate the reference points when changes in environmental conditions and/or major shifts in species abundance or community structure are observed.

Resolved-sideband Raman cooling of a bound atom to the 3D zero-point energy

International Nuclear Information System (INIS)

Monroe, C.; Meekhof, D.M.; King, B.E.; Jefferts, S.R.; Itano, W.M.; Wineland, D.J.; Gould, P.

1995-01-01

We report laser cooling of a single 9 Be + ion held in a rf (Paul) ion trap to where it occupies the quantum-mechanical ground state of motion. With the use of resolved-sideband stimulated Raman cooling, the zero point of motion is achieved 98% of the time in 1D and 92% of the time in 3D. Cooling to the zero-point energy appears to be a crucial prerequisite for future experiments such as the realization of simple quantum logic gates applicable to quantum computation. copyright 1995 The American Physical Society

Identification of voltage collapse point in self excited induction generator

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Kalyanasundaram Rajambal

2009-10-01

Full Text Available This paper presents a direct equilibrium tracing method for identifying the voltage collapse point of a self-excitedinduction generator (SEIG without many trials. The technique solves differential and algebraic equations simultaneously toobtain the variables in a single step. The load parameter is also automatically varied during equilibrium tracing and thisreduces the computational time significantly. Comparing the simulation results obtained through conventional iterative procedure shows the effectiveness of the technique. An experimental verification on a 1.5KW induction machine validates the simulation results.

Point defects in the 1 T' and 2 H phases of single-layer MoS2: A comparative first-principles study

Science.gov (United States)

Pizzochero, Michele; Yazyev, Oleg V.

2017-12-01

The metastable 1 T' phase of layered transition metal dichalcogenides has recently attracted considerable interest due to electronic properties, possible topological phases, and catalytic activity. We report a comprehensive theoretical investigation of intrinsic point defects in the 1 T' crystalline phase of single-layer molybdenum disulfide (1 T'-MoS2 ) and provide comparison to the well-studied semiconducting 2 H phase. Based on density functional theory calculations, we explore a large number of configurations of vacancy, adatom, and antisite defects and analyze their atomic structure, thermodynamic stability, and electronic and magnetic properties. The emerging picture suggests that, under thermodynamic equilibrium, 1 T'-MoS2 is more prone to hosting lattice imperfections than the 2 H phase. More specifically, our findings reveal that the S atoms that are closer to the Mo atomic plane are the most reactive sites. Similarly to the 2 H phase, S vacancies and adatoms in 1 T'-MoS2 are very likely to occur while Mo adatoms and antisites induce local magnetic moments. Contrary to the 2 H phase, Mo vacancies in 1 T'-MoS2 are expected to be an abundant defect due to the structural relaxation that plays a major role in lowering the defect formation energy. Overall, our study predicts that the realization of high-quality flakes of 1 T'-MoS2 should be carried out under very careful laboratory conditions but at the same time the facile defects introduction can be exploited to tailor physical and chemical properties of this polymorph.

Method of Fusion Diagnosis for Dam Service Status Based on Joint Distribution Function of Multiple Points

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Zhenxiang Jiang

2016-01-01

Full Text Available The traditional methods of diagnosing dam service status are always suitable for single measuring point. These methods also reflect the local status of dams without merging multisource data effectively, which is not suitable for diagnosing overall service. This study proposes a new method involving multiple points to diagnose dam service status based on joint distribution function. The function, including monitoring data of multiple points, can be established with t-copula function. Therefore, the possibility, which is an important fusing value in different measuring combinations, can be calculated, and the corresponding diagnosing criterion is established with typical small probability theory. Engineering case study indicates that the fusion diagnosis method can be conducted in real time and the abnormal point can be detected, thereby providing a new early warning method for engineering safety.

Fixed Points

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 5. Fixed Points - From Russia with Love - A Primer of Fixed Point Theory. A K Vijaykumar. Book Review Volume 5 Issue 5 May 2000 pp 101-102. Fulltext. Click here to view fulltext PDF. Permanent link:

Treating angina pectoris by acupuncture therapy.

Science.gov (United States)

Xu, Lixian; Xu, Hao; Gao, Wei; Wang, Wei; Zhang, Hui; Lu, Dominic P

2013-01-01

Acupuncture therapy on PC 6 (Neiguan) has a therapeutic effect on cardiac and chest ailments including angina pectoris. Additional beneficial acupuncture points are PC 4 (Ximen), HT 7 (Shenmen point), PC 7 (Daling point), PC 5 (Jianshi point), PC 3 (Quze point), CV 17 (Danzhong point), CV 6 (Qihai point), BL 15 (Xinshu point), L 20 (Pishu point), BL 17 (Geshu point), BL23 (Shenshu point), BL18 (Ganshu point), HT 5 (Tongli point), and ST36 (Zusanli point). Acupuncture not only quickly relieve the symptoms of acute angina pectoris, but also improve nitroglycerine's therapeutic effects. Therefore, it is an efficient simple therapeutic method used for emergency and for regular angina treatment. Review of studies on acupuncture therapy has shown effectiveness were between 80% to 96.2% that are almost as effective as conventional drug regimen. When compared with conventional medical treatment, the acupuncture therapy shows the obvious advantage of lacking, adverse side effects commonly associated with the Western anti-anginal drugs such as 1) Nitroglycerine (headache--63% with nitroglycerine patch and 50% with spray; syncope--4%; and dizziness--8% with patch; hypotension--4% with patch; and increased angina 2% with patch). 2) Isosorbide mononitrate (dizziness--3 to 5%; nausea/vomiting--2 to 4% and other reactions including hypotension, and syncope even with small doses). 3) Propranolol (bradycardia, chest pain, hypotension, worsening of AV conduction disturbance, Raynaud's syndrome, mental depression, hyperglycemia, etc.). Many conventional anti-anginal medications cause inter-drug reactions with other medications the patients taking for other diseases. Whereas, acupuncture therapy does not pose such an interference with patient's medications. Nevertheless, surgery is still the treatment of choice when acupuncture or conventional drug therapy fails. Combination of conventional drug therapy and acupuncture would considerably decrease the frequency and the required dosage