Role of Linguistic Input in Third Person Singular -"s" Use in the Speech of Young Children
ERIC Educational Resources Information Center
Finneran, Denise A.; Leonard, Laurence B.
2010-01-01
Purpose: To examine the role of linguistic input in how young, typically developing children use the 3rd person singular -"s" (3S) inflection. Method: Novel verbs were presented to 16 young children in either 3S contexts (e.g., "The tiger heens") or nonfinite (NF) contexts (e.g., "Will the tiger heen?"). The input was further manipulated for…
Wollheim, Frank A
2002-01-01
The 3rd Annual EULAR Congress, held in Stockholm on 12–15 June 2002, had a turnout of 8300 delegates, almost identical to last year's record attendance level in Prague. The venue was close to ideal, allowing ample space for poster sessions in the exhibition hall. The manned poster sessions were well attended, even on the last day of the Congress. The numerous invited speakers represented the world's elite, allowing the staging of excellent state-of-the-art podium sessions. The aim of attracting the young scientific community was partly achieved, but individual delegates' dependence on industry sponsorship poses potential problems. The organization was a big improvement compared to that of the two previous congresses. Approximately 1800 abstracts were submitted, an increase of 50%, resulting in a higher quality of accepted abstracts. The satellite symposia held every morning and late afternoon were well attended; thus, industry exposure of new products, both in podium sessions and at the exhibitions, was well accommodated. The Annual EULAR Congress consolidates its position as one of the two most important annual congresses of rheumatology, but EULAR economy and commercial aspects are still too dominant in relation to science. PMID:12223107
Singular thought: object-files, person-files, and the sortal PERSON.
Murez, Michael; Smortchkova, Joulia
2014-10-01
In philosophy, "singular thought" refers to our capacity to represent entities as individuals, rather than as possessors of properties. Philosophers who defend singularism argue that perception allows us to mentally latch onto objects and persons directly, without conceptualizing them as being of a certain sort. Singularists assume that singular thought forms a unified psychological kind, regardless of the nature of the individuals represented. Empirical findings on the special psychological role of persons as opposed to inanimates threaten singularism. They raise the possibility that tracking individuals specifically as persons might require conceptualizing them in certain ways, for example, as persons. In this paper, we take such a possibility seriously but ultimately reject it. Instead, we propose to revise a prominent singularist theory, the theory of mental files, in order to accommodate data on the psychological distinctiveness of persons: We advocate the postulation of perceptual person-files. Perceptual tracking via person-files is different from object-tracking but also from descriptive classification under the sortal concept PERSON. PMID:25155025
Hoover, Jill R; Storkel, Holly L
2013-09-01
The purpose of this study was to test the effect of manipulating verb neighbourhood density in treatment targeting the third person singular lexical affix. Using a single-subject experimental design, six pre-schoolers with Specific Language Impairment (SLI) were randomly assigned to one of two conditions: (1) treatment with sparse verbs or (2) treatment with dense verbs in 12 sessions. The third person singular lexical affix was targeted for 12 sessions of treatment in both conditions. Treatment gain and generalization were measured as the dependent variables. Third person singular % correct change from pre-treatment to post-treatment was measured using sentence production tasks with comparisons across the two treatment conditions. Treatment gain and generalization were greater for children enrolled in the sparse condition. Preliminary clinical recommendations are made and theoretical implications are discussed relative to neighbourhood density effects on lexical activation and storage in children with SLI.
Second Person Singular Address Forms in Caleno Spanish: Applying a Theory of Language Regard
ERIC Educational Resources Information Center
Newall, Gregory M.
2012-01-01
Language regard is defined as the opinions and norms that speakers have about language. In this dissertation, a theory of language regard is applied to variation in second-person singular address forms in Cali Colombian Spanish (["tuteo," "voseo", and "ustedeo" ]). This theory claims that language production and…
ERIC Educational Resources Information Center
Sundara, Megha; Demuth, Katherine; Kuhl, Patricia K.
2011-01-01
Purpose: Two-year-olds produce third person singular "-s" more accurately on verbs in sentence-final position as compared with verbs in sentence-medial position. This study was designed to determine whether these sentence-position effects can be explained by perceptual factors. Method: For this purpose, the authors compared 22- and 27-month-olds'…
2nd & 3rd Generation Vehicle Subsystems
NASA Technical Reports Server (NTRS)
2000-01-01
This paper contains viewgraph presentation on the "2nd & 3rd Generation Vehicle Subsystems" project. The objective behind this project is to design, develop and test advanced avionics, power systems, power control and distribution components and subsystems for insertion into a highly reliable and low-cost system for a Reusable Launch Vehicles (RLV). The project is divided into two sections: 3rd Generation Vehicle Subsystems and 2nd Generation Vehicle Subsystems. The following topics are discussed under the first section, 3rd Generation Vehicle Subsystems: supporting the NASA RLV program; high-performance guidance & control adaptation for future RLVs; Evolvable Hardware (EHW) for 3rd generation avionics description; Scaleable, Fault-tolerant Intelligent Network or X(trans)ducers (SFINIX); advance electric actuation devices and subsystem technology; hybrid power sources and regeneration technology for electric actuators; and intelligent internal thermal control. Topics discussed in the 2nd Generation Vehicle Subsystems program include: design, development and test of a robust, low-maintenance avionics with no active cooling requirements and autonomous rendezvous and docking systems; design and development of a low maintenance, high reliability, intelligent power systems (fuel cells and battery); and design of a low cost, low maintenance high horsepower actuation systems (actuators).
The role of utterance length and position in 3-year-olds' production of third person singular -s.
Mealings, Kiri T; Demuth, Katherine
2014-04-01
PURPOSE Evidence from children's spontaneous speech suggests that utterance length and utterance position may help explain why children omit grammatical morphemes in some contexts but not others. This study investigated whether increased utterance length (hence, increased grammatical complexity) adversely affects children's third person singular -s production in more controlled experimental conditions. METHOD An elicited imitation task with 12 Australian English-speaking children ages 2;9 (years;months) to 3;2 (Mage = 2;11) was conducted comparing third person singular -s production in 3-word and 5-word utterances, both utterance medially (e.g., He sits back; He sits back and swings) and utterance finally (e.g., There he sits; That's the way he sits) using a within-subjects design. Children were shown pictorial representations of each utterance on a computer and were invited to repeat 16 pseudorandomized prerecorded utterances. Acoustic analysis determined the presence/absence and duration of the third person singular morpheme. RESULTS Third person singular production was significantly lower utterance medially compared to utterance finally for the 5-word utterances and significantly lower utterance medially in the 5-word compared to 3-word utterances. CONCLUSION These results suggest that increased utterance length results in significantly lower third person singular production, but only in the more articulatorily challenging utterance-medial position. Thus, morpheme omission is greatest at the intersection of grammatical and phonological complexity.
Structures IVHM for 3rd Generation RLVs
NASA Technical Reports Server (NTRS)
Rogowski, Robert S.
2000-01-01
The primary goal of a Structures Integrated Vehicle Health Management (IVHM) system for 3rd generation Reusable Launch Vehicles (RLV) is to provide near 100% structural sensing coverage and thus eliminate both routine, and especially unplanned, inspections which are costly and time consuming. To meet this goal, significant advances in sensing and measurement system technology, data systems architectures, and structures based analysis methodology will be required to enable the needed large numbers of sensors with little weight penalty. This program will leverage X-33, 2nd Gen RLV, Shuttle, and Aviation Safety SIVHM system development experience to address this goal.
BACODINE/3rd Interplanetary Network burst localization
Hurley, K.; Barthelmy, S.; Butterworth, P.; Cline, T.; Sommer, M.; Boer, M.; Niel, M.; Kouveliotou, C.; Fishman, G.; Meegan, C.
1996-08-01
Even with only two widely separated spacecraft (Ulysses and GRO), 3rd Interplanetary Network (IPN) localizations can reduce the areas of BATSE error circles by two orders of magnitude. Therefore it is useful to disseminate them as quickly as possible following BATSE bursts. We have implemented a system which transmits the light curves of BACODINE/BATSE bursts directly by e-mail to UC Berkeley immediately after detection. An automatic e-mail parser at Berkeley watches for these notices, determines the Ulysses crossing time window, and initiates a search for the burst data on the JPL computer as they are received. In ideal cases, it is possible to retrieve the Ulysses data within a few hours of a burst, generate an annulus of arrival directions, and e-mail it out to the astronomical community by local nightfall. Human operators remain in this loop, but we are developing a fully automated routine which should remove them, at least for intense events, and reduce turn-around times to an absolute minimum. We explain the current operations, the data types used, and the speed/accuracy tradeoffs.
ERIC Educational Resources Information Center
Bollier, David
The 1994 Aspen Institute Roundtable on Information Technology began as a look at the changing nature of the home. In building scenarios of the "new home," the participants expressed many significant insights into issues of personal identity, community-building, and setting boundaries in our lives and environments. This report captures many of…
ERIC Educational Resources Information Center
Basterrechea, María; García Mayo, María del Pilar
2014-01-01
This study compares focus on form in Content and Language Integrated Learning (CLIL) and mainstream English as a Foreign Language (EFL) contexts in the production of a specific morphological feature, the English 3rd person singular present tense marker "-s." Research conducted in CLIL contexts to date examining morphosyntactic features…
PREFACE: 3rd International Symposium ''Optics and its Applications''
NASA Astrophysics Data System (ADS)
Calvo, M. L.; Dolganova, I. N.; Gevorgyan, N.; Guzman, A.; Papoyan, A.; Sarkisyan, H.; Yurchenko, S.
2016-01-01
The SPIE.FOCUS Armenia: 3rd International Symposium ''Optics and its Applications'' (OPTICS-2015) http://rau.am/optics2015/ was held in Yerevan, Armenia, in the period October 1 - 5, 2015. The symposium was organized by the International Society for Optics and Photonics (SPIE), the Armenian SPIE student chapter with collaboration of the Armenian TC of ICO, the Russian-Armenian University (RAU), the Institute for Physical Research of National Academy of Sciences of Armenia (IPR of NAS), the Greek-Armenian industrial company LT-PYRKAL, and the Yerevan State University (YSU). The Symposium was co-organized by the SPIE & OSA student chapters of BMSTU, the Armenian OSA student chapter, and the SPIE student chapters of Lund University and Wroclaw University of Technology. The symposium OPTICS-2015 was dedicated to the International Year of Light and Light-Based Technologies. OPTICS-2015 was devoted to modern topics and optical technologies such as: optical properties of nanostructures, silicon photonics, quantum optics, singular optics & its applications, laser spectroscopy, strong field optics, biomedical optics, nonlinear & ultrafast optics, photonics & fiber optics, and mathematical methods in optics. OPTICS-2015 was attended by 100 scientists and students representing 17 countries: Armenia, China, Czech Republic, France, Georgia, Germany, India, Iran, Italy, Latvia, Mexico, Poland, Russia, Saudi Arabia, Sweden, Ukraine, and USA. Such a broad international community confirmed the important mission of science to be a uniting force between different countries, religions, and nations. We hope that OPTICS-2015 inspired and motivated students and young scientists to work in optics and in science in general. The present volume of Journal of Physics: Conference Series includes proceedings of the symposium covering various aspects of modern problems in optics. We are grateful to all people who were involved in the organization process. We gratefully acknowledge support from
PREFACE: 3rd International Congress on Mechanical Metrology (CIMMEC2014)
NASA Astrophysics Data System (ADS)
2015-10-01
From October 14th to 16th 2014, The Brazilian National Institute of Metrology, Quality, and Technology (Inmetro) and the Brazilian Society of Metrology (SBM) organized the 3rd International Congress on Mechanical Metrology (3rd CIMMEC). The 3rd CIMMEC was held in the city of Gramado, Rio Grande do Sul, Brazil. Anticipating the interest and enthusiasm of the technical-scientific community, the Organizing Institutions invite people and organizations to participate in this important congress, reiterating the commitment to organize an event according to highest international standards. This event has been conceived to integrate people and organizations from Brazil and abroad in the discussion of advanced themes in metrology. Manufacturers and dealers of measuring equipment and standards, as well as of auxiliary accessories and bibliographic material, had the chance to promote their products and services in stands at the Fair, which has taken place alongside the Congress. The 3rd CIMMEC consisted of five Keynote Speeches and 116 regular papers. Among the regular papers, the 25 most outstanding ones, comprising a high quality content on Mechanical Metrology, were selected to be published in this issue of Journal of Physics: Conference Series. It is our great pleasure to present this volume of Journal of Physics: Conference Series to the scientific community to promote further research in Mechanical Metrology and related areas. We believe that this volume will be both an excellent source of scientific material in the fast evolving fields that were covered by CIMMEC 2014.
The Ups and Downs of 3rd Grade
ERIC Educational Resources Information Center
Felton, Kelsey Augst; Akos, Patrick
2011-01-01
The transition from 2nd to 3rd grade has received little notice in education research--yet the authors' experience in elementary school counseling convinced them that most students undergo a seismic shift during this period. Third grade is not only the first year students will encounter standardized end-of-grade tests, but also a year in which…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-10
... 3rd ACR at Fort Hood is being selected because the unit will have maximum time to convert and train... required for an SBCT, and has adequate maneuver space to accommodate SBCT training. The 3rd ACR will...
Leonard, Laurence B.; Fey, Marc E.; Deevy, Patricia; Bredin-Oja, Shelley L.
2015-01-01
We tested four predictions based on the assumption that optional infinitives can be attributed to properties of the input whereby children inappropriately extract nonfinite subject-verb sequences (e.g. the girl run) from larger input utterances (e.g. Does the girl run? Let’s watch the girl run). Thirty children with specific language impairment (SLI) and 30 typically developing children heard novel and familiar verbs that appeared exclusively either in utterances containing nonfinite subject-verb sequences or in simple sentences with the verb inflected for third person singular –s. Subsequent testing showed strong input effects, especially for the SLI group. The results provide support for input-based factors as significant contributors not only to the optional infinitive period in typical development, but also to the especially protracted optional infinitive period seen in SLI. PMID:25076070
ERIC Educational Resources Information Center
Blom, Elma; Paradis, Johanne; Duncan, Tamara Sorenson
2012-01-01
This study was designed to investigate the development of third-person singular (3SG) -"s" in children who learn English as a second language (L2). Adopting the usage-based perspective on the learning of inflection, we analyzed spontaneous speech samples collected from 15 English L2 children who were followed over a 2-year period. Assessing the…
The 3rd Annual Controlled Structures Technology Symposium
NASA Technical Reports Server (NTRS)
1991-01-01
Viewgraphs of presentations at the Controlled Structures Technology (CST) MIT Space Engineering Research Center 3rd Annual Symposium are included. Topics covered include optical interferometer testbed; active impedence matching of complex structural systems; application of CST to adaptive optics; middeck 0-G dynamics Experiment (MODE); inhibiting multiple mode vibration in controlled flexible systems; the middeck active control experiment (MACE); robust control for uncertain structures; cost averaging techniques for robust structural control; and intelligent structures technology.
Precipitation Model Validation in 3rd Generation Aeroturbine Disc Alloys
NASA Technical Reports Server (NTRS)
Olson, G. B.; Jou, H.-J.; Jung, J.; Sebastian, J. T.; Misra, A.; Locci, I.; Hull, D.
2008-01-01
In support of application of the DARPA-AIM methodology to the accelerated hybrid thermal process optimization of 3rd generation aeroturbine disc alloys with quantified uncertainty, equilibrium and diffusion couple experiments have identified available fundamental thermodynamic and mobility databases of sufficient accuracy. Using coherent interfacial energies quantified by Single-Sensor DTA nucleation undercooling measurements, PrecipiCalc(TM) simulations of nonisothermal precipitation in both supersolvus and subsolvus treated samples show good agreement with measured gamma particle sizes and compositions. Observed longterm isothermal coarsening behavior defines requirements for further refinement of elastic misfit energy and treatment of the parallel evolution of incoherent precipitation at grain boundaries.
Microstructure Modeling of 3rd Generation Disk Alloys
NASA Technical Reports Server (NTRS)
Jou, Herng-Jeng
2010-01-01
The objective of this program is to model, validate, and predict the precipitation microstructure evolution, using PrecipiCalc (QuesTek Innovations LLC) software, for 3rd generation Ni-based gas turbine disc superalloys during processing and service, with a set of logical and consistent experiments and characterizations. Furthermore, within this program, the originally research-oriented microstructure simulation tool will be further improved and implemented to be a useful and user-friendly engineering tool. In this report, the key accomplishment achieved during the second year (2008) of the program is summarized. The activities of this year include final selection of multicomponent thermodynamics and mobility databases, precipitate surface energy determination from nucleation experiment, multiscale comparison of predicted versus measured intragrain precipitation microstructure in quench samples showing good agreement, isothermal coarsening experiment and interaction of grain boundary and intergrain precipitates, primary microstructure of subsolvus treatment, and finally the software implementation plan for the third year of the project. In the following year, the calibrated models and simulation tools will be validated against an independently developed experimental data set, with actual disc heat treatment process conditions. Furthermore, software integration and implementation will be developed to provide material engineers valuable information in order to optimize the processing of the 3rd generation gas turbine disc alloys.
Designing a 3rd generation, authenticatable attribute measurement system
Thron, Jonathan; Karpius, Peter; Santi, Peter; Smith, Morag; Vo, Duc; Williams, Richard
2009-01-01
Attribute measurement systems (AMS) are designed to measure potentially sensitive items containing Special Nuclear Materials to determine if the items possess attributes which fall within an agreed-upon range. Such systems could be used in a treaty to inspect and verify the identity of items in storage without revealing any sensitive information associated with the item. An AMS needs to satisfy two constraints: the host party needs to be sure that none of their sensitive information is released, while the inspecting party wants to have confidence that the limited amount of information they see accurately reflects the properties of the item being measured. The former involves 'certifying' the system and the latter 'authenticating' it. Previous work into designing and building AMS systems have focused more on the questions of certifiability than on the questions of authentication - although a few approaches have been investigated. The next step is to build a 3rd generation AMS which (1) makes the appropriate measurements, (2) can be certified, and (3) can be authenticated (the three generations). This paper will discuss the ideas, options, and process of producing a design for a 3rd generation AMS.
The development of 3rd generation IR detectors at AIM
NASA Astrophysics Data System (ADS)
Ziegler, J.; Eich, D.; Mahlein, M.; Schallenberg, T.; Scheibner, R.; Wendler, J.; Wenisch, J.; Wollrab, R.; Daumer, V.; Rehm, R.; Rutz, F.; Walther, M.
2011-06-01
3rd generation IR modules - dual-color (DC), dual-band (DB), and large format two-dimensional arrays - require sophisticated production technologies such as molecular beam epitaxy (MBE) as well as new array processing techniques, which can satisfy the rising demand for increasingly complex device structures and low cost detectors. AIM will extend its future portfolio by high performance devices which make use of these techniques. The DC MW / MW detectors are based on antimonide type-II superlattices (produced by MBE at Fraunhofer IAF, Freiburg) in the 384x288 format with a 40 μm pitch. For AIM, the technology of choice for MW / LW DB FPAs is MCT MBE on CdZnTe substrates, which has been developed in cooperation with IAF, Freiburg. 640x512, 20 μm pitch Focal Plane Arrays (FPAs) have been processed at AIM. The growth of MW MCT MBE layers on alternate substrates is challenging, but essential for competitive fabrication of large two-dimensional arrays such as megapixel (MW 1280x1024, 15 μm pitch) FPAs. This paper will present the development status and latest results of the above-mentioned 3rd Gen FPAs and Integrated Detector Cooler Assemblies (IDCAs).
3rd grade English language learners making sense of sound
NASA Astrophysics Data System (ADS)
Suarez, Enrique; Otero, Valerie
2013-01-01
Despite the extensive body of research that supports scientific inquiry and argumentation as cornerstones of physics learning, these strategies continue to be virtually absent in most classrooms, especially those that involve students who are learning English as a second language. This study presents results from an investigation of 3rd grade students' discourse about how length and tension affect the sound produced by a string. These students came from a variety of language backgrounds, and all were learning English as a second language. Our results demonstrate varying levels, and uses, of experiential, imaginative, and mechanistic reasoning strategies. Using specific examples from students' discourse, we will demonstrate some of the productive aspects of working within multiple language frameworks for making sense of physics. Conjectures will be made about how to utilize physics as a context for English Language Learners to further conceptual understanding, while developing their competence in the English language.
3rd annual symposium of chemical and pharmaceutical structure analysis.
Weng, Naidong; Zheng, Jenny; Lee, Mike
2012-08-01
The 3rd Annual Symposium on Chemical and Pharmaceutical Structure Analysis was once again held in Shanghai, where a rich history of 'East meets West' continued. This meeting is dedicated to bringing together scientists from pharmaceutical companies, academic institutes, CROs and instrument vendors to discuss current challenges and opportunities on the forefront of pharmaceutical research and development. The diversified symposia and roundtables are highly interactive events where scientists share their experiences and visions in a collegial setting. The symposium highlighted speakers and sessions that provided first-hand experiences as well as the latest guidance and industrial/regulatory thinking, which was reflected by the theme of this year's meeting 'From Bench to Decision Making - from Basics to Application.' In addition to the highly successful Young Scientist Excellence Award, new events were featured at this year's meeting, such as the Executive Roundtable and the inaugural Innovator Award.
Results from the UK 3rd generation programme: Albion
NASA Astrophysics Data System (ADS)
McEwen, R. K.; Axcell, C.; Knowles, P.; Hoade, K. P.; Wilson, M.; Dennis, P. N. J.; Backhouse, P.; Gordon, N. T.
2008-10-01
Following the development of 1st Generation systems in the 1970s, thermal imaging has been in service with the UK armed forces for over 25 years and has proven itself to be a battle winning technology. More recently the wider accessibility to similar technologies within opposing forces has reduced the military advantage provided by these 1st Generation systems and a clear requirement has been identified by the UK MOD for thermal imaging sensors providing increased detection, recognition and identification (DRI) ranges together with a simplified logistical deployment burden and reduced through-life costs. In late 2005, the UK MOD initiated a programme known as "Albion" to develop high performance 3rd Generation single waveband infrared detectors to meet this requirement. At the same time, under a separate programme supporting higher risk technology, a dual waveband infrared detector was also developed. The development phase of the Albion programme has now been completed and prototype detectors are now available and have been integrated into demonstration thermal imaging cameras. The Albion programme has now progressed into the second phase, incorporating both single and dual waveband devices, focussing on low rate initial production (LRIP) and qualification of the devices for military applications. All of the detectors have been fabricated using cadmium mercury telluride material (CMT), grown by metal organic vapour phase epitaxy (MOVPE) on low cost, gallium arsenide (GaAs) substrates and bump bonded to the silicon read out circuit (ROIC). This paper discusses the design features of the 3rd Generation detectors developed in the UK together with the results obtained from the prototype devices both in the laboratory and when integrated into field deployable thermal imaging cameras.
Beyond 3rd generation MCT: SXGA QWIP (Invited Paper)
NASA Astrophysics Data System (ADS)
Crawford, Stewart; Skivington, Tracey; Craig, Robert; Haining, Andrew; Costard, Eric; Belhaire, Eric; Bois, Philippe
2005-05-01
Successful past experience of implementing long wave MCT 1st and 2nd Generation thermal imagers has demonstrated to THALES Optronics that MCT presents difficult challenges when correcting non-uniformity errors caused by rapidly changing detector element gain and offset drifts. These problems become even more demanding when the move is made from long linear arrays to focal plane arrays due to the significantly larger number of detector elements. Relaxation of these demands would make a significant impact on the price/performance trade which inevitably occurs in a camera development. In recognition of the need to offer UK MOD best value, THALES Optronics has initiated a programme to achieve a SXGA resolution camera and is working with UK MOD, over a two year period, to investigate whether an alternative technology can maintain the high resolution required whilst achieving a downward step change in price. The selected technology is 3rd Generation Gallium Arsenide long wave Quantum Well Infra-red Photodiode (QWIP) chosen because initial indications are that drift rates are orders of magnitude slower than MCT. The programme involves studies to determine effects of defect clusters, bimodalism, non-uniformity correction levels and higher than normal operating temperatures on achieving acceptable performance, including logistics, in user scenarios whilst maximising detector yield. Development of demonstrator IR camera hardware (technology readiness level 6/7) based on a THALES Research & Technology QWIP array is also part of the programme.
Development of the 3rd Generation ECR ion source
Lyneis, C.M.; Xie, Z.Q.; Taylor, C.E.
1997-09-01
The LBNL 3rd Generation ECR ion source has progressed from a concept to the fabrication of a full scale prototype superconducting magnet structure. This new ECR ion source will combine the recent ECR ion source techniques that significantly enhance the production of high charge state ions. The design includes a plasma chamber made from aluminum to provide additional cold electrons, three separate microwave feeds to allow multiple-frequency plasma heating (at 10, 14 and 18 GHz or at 6, 10 and 14 GHz) and very high magnetic mirror fields. The design calls for mirror fields of 4 T at injection and 3 T at extraction and for a radial field strength at the wall of 2.4 T. The prototype superconducting magnet structure which consists of three solenoid coils and six race track coils with iron poles forming the sextupole has been tested in a vertical dewar. After training, the sextupole magnet reached 105% of its design current with the solenoids off. With the solenoids operating at approximately 70% of their full design field, the sextuple coils operated at 95% of the design value which corresponds to a sextupole field strength at the plasma wall of more than 2.1 T.
80. GENERAL VIEW TO NORTH ON 3RD AVENUE EL AT ...
80. GENERAL VIEW TO NORTH ON 3RD AVENUE EL AT GUN HILL STATION. 7TH AVENUE EL EXPRESS IS VISIBLE ABOVE THE 3RD AVENUE EL WHICH JOINED ONTO THE SAME STRUCTURE AT GUN HILL ROAD. NOTE: GUN HILL ROAD IS THE NORTH TERMINUS OF THE 3RD AVENUE ELEVATED. TRAINS DID NOT CARRY PASSENGERS BEYOND THIS POINT, ALTHOUGH THE 3RD AVENUE TRACK DID EXTEND FURTHER NORTH FOR SWITCHING PURPOSES AND INTO THE YARDS. - Interborough Rapid Transit Company, Third Avenue Elevated Line, Borough of the Bronx, New York County, NY
PREFACE: 3rd International Conference of Mechanical Engineering Research (ICMER 2015)
NASA Astrophysics Data System (ADS)
Mamat, Riazalman; Rahman, Mustafizur; Mohd. Zuki Nik Mohamed, Nik; Che Ghani, Saiful Anwar; Harun, Wan Sharuzi Wan
2015-12-01
The 3rd ICMER2015 is the continuity of the NCMER2010. The year 2010 represents a significant milestone in the history for Faculty of Mechanical Engineering, Universiti Malaysia Pahang (UMP) Malaysia with the organization of the first and second national level conferences (1st and 2nd NCMER) at UMP on May 26-27 and Dec 3-4 2010. The Faculty then changed the name from National Conference on Mechanical Engineering Research (NCMER) to International Conference on Mechanical Engineering Research (ICMER) in 2011 and this year, 2015 is our 3rd ICMER. These proceedings contain the selected scientific manuscripts submitted to the conference. It is with great pleasure to welcome you to the "International Conference on Mechanical Engineering Research (ICMER2015)" that is held at Zenith Hotel, Kuantan, Malaysia. The call for papers attracted submissions of over two hundred abstracts from twelve different countries including Japan, Iran, China, Kuwait, Indonesia, Norway, Philippines, Morocco, Germany, UAE and more. The scientific papers published in these proceedings have been revised and approved by the technical committee of the 3rd ICMER2015. All of the papers exhibit clear, concise, and precise expositions that appeal to a broad international readership interested in mechanical engineering, combustion, metallurgy, materials science as well as in manufacturing and biomechanics. The reports present original ideas or results of general significance supported by clear reasoning and compelling evidence, and employ methods, theories and practices relevant to the research. The authors clearly state the questions and the significance of their research to theory and practice, describe how the research contributes to new knowledge, and provide tables and figures that meaningfully add to the narrative. In this edition of ICMER representatives attending are from academia, industry, governmental and private sectors. The plenary and invited speakers will present, discuss, promote and
Design of the 3rd generation ECR ion source
Lyneis, C.M.; Xie, Z.Q.; Taylor, C.E.
1997-02-01
Development of the 3rd Generation ECR ion source has progressed from a concept described in the last ECR Ion Source Workshop to the fabrication of a full scale prototype superconducting magnet structure. The prototype consists of three solenoid coils and six race track coils with iron poles forming the sextupole. The design calls for mirror fields of 4 T at injection and 3 T at extraction and for a radial field strength at the wall of 2.4 T. The prototype magnet will be tested this spring in an existing vertical cryostat to determine its operating characteristics including maximum operating values, training characteristics and to study the interaction between the solenoid and sextupole coils. Design of the ECR plasma chamber includes aluminum walls to provide an enhanced source of cold electrons, up to three separate microwave feeds to allow simultaneous heating of the plasma electrons at 10, 14 and 18 GHz or at 6, 10 and 14 GHz. Water cooling of the plasma chamber walls and the injection and extraction plates is planned so that up to 10 kW of microwave power can be used without excessive heating of the chamber components. Experience with the AECR-U at LBNL shows that increasing the magnetic fields and using two frequency heating allows operation at lower neutral pressures and higher microwave power density. Both of these conditions are needed to produce very high charge states from elements with masses greater than xenon and the resulting higher energy, more intense heavy beams from the 88-Inch Cyclotron would provide new research opportunities.
PREFACE: 3rd International Congress on Ceramics (ICC3)
NASA Astrophysics Data System (ADS)
Niihara, Koichi; Ohji, Tatsuki; Sakka, Yoshio
2011-10-01
Early in 2005, the American Ceramic Society, the European Ceramic Society and the Ceramic Society of Japan announced a collaborative effort to provide leadership for the global ceramics community that would facilitate the use of ceramic and glass materials. That effort resulted in an agreement to organize a new biennial series of the International Congress on Ceramics, convened by the International Ceramic Federation (ICF). In order to share ideas and visions of the future for ceramic and glass materials, the 1st International Congress on Ceramics (ICC1) was held in Canada, 2006, under the organization of the American Ceramic Society, and the 2nd Congress (ICC2) was held in Italy, 2008, hosted by the European Ceramic Society. Organized by the Ceramic Society of Japan, the 3rd Congress (ICC3) was held in Osaka, Japan, 14-18 November 2010. Incorporating the 23rd Fall Meeting of the Ceramic Society of Japan and the 20th Iketani Conference, ICC3 was also co-organized by the Iketani Science and Technology Foundation, and was endorsed and supported by ICF, Asia-Oceania Ceramic Federation (AOCF) as well as many other organizations. Following the style of the previous two successful Congresses, the program was designed to advance ceramic and glass technologies to the next generation through discussion of the most recent advances and future perspectives, and to engage the worldwide ceramics community in a collective effort to expand the use of these materials in both conventional as well as new and exciting applications. ICC3 consisted of 22 voluntarily organized symposia in the most topical and essential themes of ceramic and glass materials, including Characterization, design and processing technologies Electro, magnetic and optical ceramics and devices Energy and environment related ceramics and systems Bio-ceramics and bio-technologies Ceramics for advanced industry and safety society Innovation in traditional ceramics It also contained the Plenary Session and the
NASA Technical Reports Server (NTRS)
Swedlow, J. L.
1976-01-01
An approach is described for singularity computations based on a numerical method for elastoplastic flow to delineate radial and angular distribution of field quantities and measure the intensity of the singularity. The method is applicable to problems in solid mechanics and lends itself to certain types of heat flow and fluid motion studies. Its use is not limited to linear, elastic, small strain, or two-dimensional situations.
Rentz's Student Affairs Practice in Higher Education. 3rd Edition
ERIC Educational Resources Information Center
MacKinnon, Fiona J. D.
2004-01-01
Students in the field, as well as experienced practitioners and administrators, will herein find an up-to-date and in-depth study of the major student affairs functions of a comprehensive campus program. Within its covers, the graduate student will find chapters describing everything the person new to student affairs needs to know about the major…
1. WEST SIDE AND ENTRY, FROM ACROSS 3RD STREET, LOOKING ...
1. WEST SIDE AND ENTRY, FROM ACROSS 3RD STREET, LOOKING EAST. - Oakland Naval Supply Center, Administration Building-Dental Annex-Dispensary, Between E & F Streets, East of Third Street, Oakland, Alameda County, CA
The outcomes of therapeutic decision in lower 3rd rectal cancer patients.
Chen, Chien-Hsin; Wei, Po-Li; Hsieh, Mao-Chih; Lin, En-Kwang; Chiou, Jeng-Fong; Lu, Yen-Jung; Wu, Szu-Yuan
2016-09-01
To investigate the outcomes of the selective neoadjuvant concurrent chemoradiotherapy (CCRT) in lower 3rd rectal cancer patients in different groups (with or without neoadjuvant CCRT), especially in survival rate, local recurrence rate, and sphincter preservation rate.From January 1999 to December 2012, 69 consecutive patients who had histologically proven adenocarcinoma of lower 3rd rectum, defined preoperatively as lower tumor margin within 7 cm from the anal verge as measured by rigid sigmoidoscopy, received total mesorectum excision (TME). Our inclusion criteria of neoadjuvant CCRT are lower 3rd rectal cancer, stage II/III, and large (diameter >5 cm or >1/2 of circumference). Neoadjuvant concurrent CCRT had begun to apply lower 3rd rectal cancer patients or not. The radiation techniques of neoadjuvant CCRT for lower 3rd rectal cancer patients were all conventional fraction intensity modulated radiotherapy (IMRT) and concurrent fluoropyrimidine chemotherapy.Five-year overall survival rate, disease-free survival rate, and local recurrence rate for lower 3rd rectal cancer patients in group I were 51%, 45%, and 25%, respectively. On the contrary, 5-year overall survival rate, disease-free survival rate, and local recurrence rate for lower rectal cancer patients in group II were 70%, 70%, and 3%, respectively. The 5-year sphincter sparing rate was increased from 38.2% to 100% after the beginning of neoadjuvant CCRT. Analyzing local recurrence, overall survival rate, disease-specific survival rate, and sphincter sparing rate in group II were statistically significant superior to group I.Five-year overall survival rate, disease-free survival rate, and sphincter sparing rate for lower 3rd rectal cancer patients were improved after the addition of neoadjuvant CCRT. No unacceptable toxicity was noted after conventional fraction IMRT and concurrent fluoropyrimidine chemotherapy. Our study showed neoadjuvant CCRT could be valuable for lower 3rd rectal cancer patients
ERIC Educational Resources Information Center
Danhauer, Jeffrey L.; Johnson, Carole E.; Caudle, Abby T.
2011-01-01
Purpose: Ear infections are prevalent in kindergarten through 3rd-grade (K-3rd) children and can affect their performance at school. Chewing gum, when administered by parents and teachers, can help prevent ear infections in children. This pilot study surveyed K-3rd-grade teachers in the Santa Barbara School Districts to assess their knowledge…
3rd International Conference on Turbulent Mixing and Beyond
NASA Astrophysics Data System (ADS)
Abarzhi, Snezhana I.; Gauthier, Serge; Keane, Christopher J.; Niemela, Joseph J.
2013-07-01
non-equilibrium heat transfer, strong shocks and explosions, material transformation under high strain rate, supernovae and accretion discs, stellar non-Boussinesq and magneto-convection, planetary interiors and mantle-lithosphere tectonics, premixed and non-premixed combustion, non-canonical wall-bounded flows, hypersonic and supersonic boundary layers, dynamics of atmosphere and oceanography, are just a few examples to list. A grip on non-equilibrium turbulent processes is crucial for cutting-edge technology such as laser micro-machining, nano-electronics, free-space optical telecommunications and for industrial applications in the areas of aeronautics and aerodynamics. Non-equilibrium turbulent processes are anisotropic, non-local, multi-scale and multi-phase, and often are driven by shocks or acceleration. Their scaling, spectral and invariant properties differ substantially from those of classical Kolmogorov turbulence. At atomistic and meso-scales, the non-equilibrium dynamics depart dramatically from a standard scenario given by Gibbs statistic ensemble average and quasi-static Boltzmann equation. The singular aspect and the similarity of the non-equilibrium dynamics at macroscopic scales are interplayed with the fundamental properties of the Euler and compressible Navier-Stokes equations and with the problem sensitivity to the boundary conditions at discontinuities. The state-of-the-art numerical simulations of multi-phase flows suggest new methods for predictive modelling of the multi-scale non-equilibrium dynamics in fluids and plasmas, for error estimates and uncertainty quantifications, as well as for novel data assimilation techniques. 3. International Conference 'Turbulent Mixing and Beyond' The First and Second International Conferences on Turbulent Mixing and Beyond found that: (i) TMB-related problems have in common a set of outstanding research issues; (ii) their solution has a potential to significantly advance a variety of disciplines in science
Craigie, Jillian
2015-01-01
The United Nations Convention on the Rights of Persons with Disabilities (CRPD) is being used to argue for wider recognition of the legal capacity of people with mental disabilities. This raises a question about the implications of the Convention for attributions of criminal responsibility. The present paper works towards an answer by analysing the relationship between legal capacity in relation to personal decisions and criminal acts. Its central argument is that because moral and political considerations play an essential role in setting the relevant standards, legal capacity in the context of personal decisions and criminal acts should not be thought of as two sides of the same coin. The implications of particular moral or political norms are likely to be different in these two legal contexts, and this may justify asymmetries in the relevant standards for legal capacity. However, the analysis highlights a fundamental question about how much weight moral or political considerations should be given in setting these standards, and this is used to frame a challenge to those calling for significantly wider recognition of the legal capacity of people with mental disabilities on the basis of the Convention. PMID:25997381
3rd International Conference on Turbulent Mixing and Beyond
NASA Astrophysics Data System (ADS)
Abarzhi, Snezhana I.; Gauthier, Serge; Keane, Christopher J.; Niemela, Joseph J.
2013-07-01
non-equilibrium heat transfer, strong shocks and explosions, material transformation under high strain rate, supernovae and accretion discs, stellar non-Boussinesq and magneto-convection, planetary interiors and mantle-lithosphere tectonics, premixed and non-premixed combustion, non-canonical wall-bounded flows, hypersonic and supersonic boundary layers, dynamics of atmosphere and oceanography, are just a few examples to list. A grip on non-equilibrium turbulent processes is crucial for cutting-edge technology such as laser micro-machining, nano-electronics, free-space optical telecommunications and for industrial applications in the areas of aeronautics and aerodynamics. Non-equilibrium turbulent processes are anisotropic, non-local, multi-scale and multi-phase, and often are driven by shocks or acceleration. Their scaling, spectral and invariant properties differ substantially from those of classical Kolmogorov turbulence. At atomistic and meso-scales, the non-equilibrium dynamics depart dramatically from a standard scenario given by Gibbs statistic ensemble average and quasi-static Boltzmann equation. The singular aspect and the similarity of the non-equilibrium dynamics at macroscopic scales are interplayed with the fundamental properties of the Euler and compressible Navier-Stokes equations and with the problem sensitivity to the boundary conditions at discontinuities. The state-of-the-art numerical simulations of multi-phase flows suggest new methods for predictive modelling of the multi-scale non-equilibrium dynamics in fluids and plasmas, for error estimates and uncertainty quantifications, as well as for novel data assimilation techniques. 3. International Conference 'Turbulent Mixing and Beyond' The First and Second International Conferences on Turbulent Mixing and Beyond found that: (i) TMB-related problems have in common a set of outstanding research issues; (ii) their solution has a potential to significantly advance a variety of disciplines in science
Collaborative study for the establishment of the 3rd international standard for neomycin.
Rautmann, G; Daas, A; Buchheit, K-H
2013-01-01
An international collaborative study was organised to establish the World Health Organization (WHO) 3(rd) International Standard (IS) for neomycin. Ten laboratories from different countries participated in the collaborative study. The potency of the candidate material, a freeze-dried preparation, was estimated by microbiological assays with sensitive micro-organisms. To ensure continuity between consecutive batches, the 2(nd) IS for neomycin was used as a standard. Based on the results of the study, the 3(rd) IS for neomycin was adopted at the meeting of the WHO Expert Committee on Biological Standardization (ECBS) in 2012 with an assigned potency of 19,050 IU per vial. The 3(rd) IS for neomycin is available from the European Directorate for the Quality of Medicines & HealthCare (EDQM).
Radiographic findings on 3rd molars removed in 20-year-old men.
Rajasuo, Ari; Peltola, Jaakko; Ventä, Irja; Murtomaa, Heikki
2003-10-01
In this study we assess radiographic findings characteristic of mandibular 3rd molars that had required either routine or surgical extraction. X-ray findings relating to acute pericoronitis were also examined. The material was collected by investigating patient records and rotational panoramic radiographs of 20-year-old Finnish male conscripts (n = 738) treated during military service because of 3rd-molar-related problems. The follicle around the crown of mandibular 3rd molars with acute pericoronitis was enlarged in 19% of cases and in 13% of chronic symptom-free pericoronitis cases (not statistically significant difference). Mandibular 3rd molars extracted surgically were more often mesially inclined than those extracted routinely (61% vs. 23%; P < 0.001), partially or totally intrabony impacted (92% vs. 66%; P < 0.001) and deep situated (on average 4.2 mm vs. 2.5 mm under the occlusal plane). Surgical extraction was also associated with the roots completely developed [92% vs. 84% of the teeth routinely extracted, odds ratio (OR) 2.6, 95% confidence interval (CI) 1.2-5.5] and with the absence of radiographic pericoronitis [around 27% vs. 39% of the teeth routinely extracted (OR 0.5, 95% CI 0.3-0.8)]. In 86% of cases the space between 2nd molar and ramus of the mandible was narrower than the 3rd molar extracted surgically, whereas this was 62% in routine extraction cases (P < 0.001). We conclude that there are some typical 3rd-molar findings in rotational panoramic radiographs that show a need for surgical extraction.
Radiographic findings on 3rd molars removed in 20-year-old men.
Rajasuo, Ari; Peltola, Jaakko; Ventä, Irja; Murtomaa, Heikki
2003-10-01
In this study we assess radiographic findings characteristic of mandibular 3rd molars that had required either routine or surgical extraction. X-ray findings relating to acute pericoronitis were also examined. The material was collected by investigating patient records and rotational panoramic radiographs of 20-year-old Finnish male conscripts (n = 738) treated during military service because of 3rd-molar-related problems. The follicle around the crown of mandibular 3rd molars with acute pericoronitis was enlarged in 19% of cases and in 13% of chronic symptom-free pericoronitis cases (not statistically significant difference). Mandibular 3rd molars extracted surgically were more often mesially inclined than those extracted routinely (61% vs. 23%; P < 0.001), partially or totally intrabony impacted (92% vs. 66%; P < 0.001) and deep situated (on average 4.2 mm vs. 2.5 mm under the occlusal plane). Surgical extraction was also associated with the roots completely developed [92% vs. 84% of the teeth routinely extracted, odds ratio (OR) 2.6, 95% confidence interval (CI) 1.2-5.5] and with the absence of radiographic pericoronitis [around 27% vs. 39% of the teeth routinely extracted (OR 0.5, 95% CI 0.3-0.8)]. In 86% of cases the space between 2nd molar and ramus of the mandible was narrower than the 3rd molar extracted surgically, whereas this was 62% in routine extraction cases (P < 0.001). We conclude that there are some typical 3rd-molar findings in rotational panoramic radiographs that show a need for surgical extraction. PMID:14763776
16. 3RD FLOOR, J.M. LEHMANN CO. FIVEROLL TOILET SOAP MILL ...
16. 3RD FLOOR, J.M. LEHMANN CO. FIVE-ROLL TOILET SOAP MILL INSTALLED 1950, TO WEST; BUCKET CONVEYOR AT RIGHT MOVED WASTE FROM 2ND FLOOR SOAP PRESSES TO 5TH FLOOR RE-MANUFACTURE - Colgate & Company Jersey City Plant, Building No. B-14, 54-58 Grand Street, Jersey City, Hudson County, NJ
75 FR 34450 - Filing Dates for the Indiana Special Election in the 3rd Congressional District
Federal Register 2010, 2011, 2012, 2013, 2014
2010-06-17
... From the Federal Register Online via the Government Publishing Office FEDERAL ELECTION COMMISSION Filing Dates for the Indiana Special Election in the 3rd Congressional District AGENCY: Federal Election Commission. ACTION: Notice of filing dates for special election. SUMMARY: Indiana has scheduled a...
Sebastian, Shaji; Hernández, Vincent; Myrelid, Pär; Kariv, Revital; Tsianos, Epameinondas; Toruner, Murat; Marti-Gallostra, Marc; Spinelli, Antonino; van der Meulen-de Jong, Andrea E; Yuksel, Elif Sarıtas; Gasche, Christoph; Ardizzone, Sandro; Danese, Silvio
2014-01-01
Epidemiological studies demonstrate an increased risk of colorectal cancer in patients with inflammatory bowel disease (IBD). A detailed literature review was conducted on epidemiology, risk factors, pathophysiology, chemoprevention and outcomes of colorectal cancer (CRC) in IBD as part of the 3rd ECCO scientific pathogenesis workshop.
PreK-3rd: What Is the Price Tag? Policy to Action Brief. No. 2
ERIC Educational Resources Information Center
Shore, Rima
2009-01-01
In an era of intense fiscal pressures, educators are focusing on those investments most likely to lift student achievement. They are also trying to make more strategic use of existing resources. To achieve these goals, a growing number of policymakers are considering integrated PreK-3rd approaches. Increasingly, they are recognizing that the first…
Evaluation of the "Respect Not Risk" Firearm Safety Lesson for 3rd-Graders
ERIC Educational Resources Information Center
Liller, Karen D.; Perrin, Karen; Nearns, Jodi; Pesce, Karen; Crane, Nancy B.; Gonzalez, Robin R.
2003-01-01
The purpose of this study was to evaluate the MORE HEALTH "Respect Not Risk" Firearm Safety Lesson for 3rd-graders in Pinellas County, Florida. Six schools representative of various socioeconomic levels were selected as the test sites. Qualitative and quantitative data were collected. A total of 433 matched pretests/posttests were used to…
Prediction of High School Dropout or Graduation from 3rd Grade Data.
ERIC Educational Resources Information Center
Lloyd, Dee Norman; Bleach, Gail
Measures of background characteristics, school performance, and tested achievement were analyzed for four race-by-sex samples of 3rd graders who were known to have later become high school dropouts or graduates. Results showed that as early as five to eight years before leaving school, dropouts differed significantly from graduates in age, tested…
Using Food as a Tool to Teach Science to 3rd Grade Students in Appalachian Ohio
ERIC Educational Resources Information Center
Duffrin, Melani W.; Hovland, Jana; Carraway-Stage, Virginia; McLeod, Sara; Duffrin, Christopher; Phillips, Sharon; Rivera, David; Saum, Diana; Johanson, George; Graham, Annette; Lee, Tammy; Bosse, Michael; Berryman, Darlene
2010-01-01
The Food, Math, and Science Teaching Enhancement Resource (FoodMASTER) Initiative is a compilation of programs aimed at using food as a tool to teach mathematics and science. In 2007 to 2008, a foods curriculum developed by professionals in nutrition and education was implemented in 10 3rd-grade classrooms in Appalachian Ohio; teachers in these…
The Effect of Book Blogging on the Motivation of 3rd-Grade Students
ERIC Educational Resources Information Center
Swanson, Kristen N.; Legutko, Robert S.
2008-01-01
A Web 2.0 technology was implemented during reading instruction in one 3rd-grade classroom in suburban southeastern Pennsylvania. Trained preservice teachers provided feedback to students via the World Wide Web to enhance their performance and social connections. Motivation scores were measured before and after the intervention was implemented. A…
ERIC Educational Resources Information Center
Bullock, Charles C.; Mahon, Michael J.; Killingsworth, Charles L.
2010-01-01
Ultimately, all successful recreation programs center around its participants wants and needs. Serving people with disabilities is no exception. "Introduction to Recreation Services for People with Disabilities" is intended to be an introductory book for anyone planning or working in the parks, recreation, and leisure service industry. Through…
Understanding Singular Vectors
ERIC Educational Resources Information Center
James, David; Botteron, Cynthia
2013-01-01
matrix yields a surprisingly simple, heuristical approximation to its singular vectors. There are correspondingly good approximations to the singular values. Such rules of thumb provide an intuitive interpretation of the singular vectors that helps explain why the SVD is so…
ERIC Educational Resources Information Center
Foorman, Barbara; Beyler, Nicholas; Borradaile, Kelley; Coyne, Michael; Denton, Carolyn A.; Dimino, Joseph; Furgeson, Joshua; Hayes, Lynda; Henke, Juliette; Justice, Laura; Keating, Betsy; Lewis, Warnick; Sattar, Samina; Streke, Andrei; Wagner, Richard; Wissel, Sarah
2016-01-01
The goal of this practice guide is to offer educators specific, evidence-based recommendations for teaching foundational reading skills to students in kindergarten through 3rd grade. This guide is a companion to the existing practice guide, "Improving Reading Comprehension in Kindergarten Through 3rd Grade", and as a set, these guides…
Breda, Massimo; Garofolo, Fabio; Caturla, Maria Cruz; Couerbe, Philippe; Maltas, John; White, Peter; Struwe, Petra; Sangster, Timothy; Riches, Suzanne; Hillier, Jim; Garofolo, Wei; Zimmerman, Thomas; Pawula, Maria; Collins, Eileen; Schoutsen, Dick; Wieling, Jaap; Green, Rachel; Houghton, Richard; Jeanbaptiste, Bernard; Claassen, Quinton; Harter, Tammy; Seymour, Mark
2011-12-01
The 3rd Global CRO Council Closed Forum was held on the 3rd and 4th July 2011 in Guildford, United Kingdom, in conjunction with the 19th International Reid Bioanalytical Forum. In attendance were 21 senior-level representatives from 19 CROs on behalf of nine European countries and, for many of the attendees, this occasion was the first time that they had participated in a GCC meeting. Therefore, this closed forum was an opportunity to increase awareness of the aim of the GCC and how it works, share information about bioanalytical regulations and audit findings from different agencies, their policies and procedures and also to discuss some topics of interest and aim to develop ideas and provide recommendations for bioanalytical practices at future GCC meetings in Europe.
3rd Workshop on Semantic Ambient Media Experience (SAME) - In Conjunction with AmI-2010
NASA Astrophysics Data System (ADS)
Lugmayr, Artur; Stockleben, Bjoern; Kaario, Juha; Pogorelc, Bogdan; Risse, Thomas
The SAME workshop takes place for the 3rd time in 2010, and it's theme in this year was creating the business value-creation, vision, media theories and technology for ambient media. SAME differs from other workshops due to its interactive and creative touch and going beyond simple powerpoint presentations. Several results will be published by AMEA - the AMbient Media Association (www.ambientmediaassociation.org.
Higher order modes of a 3rd harmonic cavity with an increased end-cup iris
T. Khabibouline; N. Solyak; R. Wanzenberg
2003-05-19
The cavity design for a 3rd harmonic cavity for the TTF 2 photoinjector has been revised to increase the coupling between the main coupler and the cavity cells. The iris radius of the end cup of the cavity has been increased to accomplish a better coupling. The basic rf-parameters and the higher order modes of the modified design are summarized in this report.
Insights from the 3rd World Congress on Integrated Computational Materials Engineering
NASA Astrophysics Data System (ADS)
Howe, D.; Goodlet, B.; Weaver, J.; Spanos, G.
2016-05-01
The 3rd World Congress on Integrated Computational Materials Engineering (ICME) was a forum for presenting the "state-of-the-art" in the ICME discipline, as well as for charting a path for future community efforts. The event concluded with in an interactive panel-led discussion that addressed such topics as integrating efforts between experimental and computational scientists, uncertainty quantification, and identifying the greatest challenges for future workforce preparation. This article is a summary of this discussion and the thoughts presented.
13. Photocopy of 1920 drawing titled: BUILDING 78, 3RD FLOOR ...
13. Photocopy of 1920 drawing titled: BUILDING 78, 3RD FLOOR BALCONY AND FIRE ESCAPES, including plans for skylight and North Elevation. HABS photograph is an 8x10' contact print made from a high contrast negative of an enlargement made from microfiche. Original is in the collection of Department of Public Works, Puget Sound Naval Shipyard, Bremerton, WA. - Puget Sound Naval Shipyard, Administration Building, Farragut Avenue, Bremerton, Kitsap County, WA
The Goodrich 3rd generation DB-110 system: successful flight test on the F-16 aircraft
NASA Astrophysics Data System (ADS)
Lange, Davis; Iyengar, Mrinal; Maver, Larry; Dyer, Gavin; Francis, John
2007-04-01
The 3rd Generation Goodrich DB-110 system provides users with a three (3) field-of-view high performance Airborne Reconnaissance capability that incorporates a dual-band day and nighttime imaging sensor, a real time recording and a real time data transmission capability to support long range, medium range, and short range standoff and over-flight mission scenarios, all within a single pod. Goodrich developed their 3rd Generation Airborne Reconnaissance Pod for operation on a range of aircraft types including F-16, F-15, F-18, Euro-fighter and older aircraft such as the F-4, F-111, Mirage and Tornado. This system upgrades the existing, operationally proven, 2nd generation DB-110 design with enhancements in sensor resolution, flight envelope and other performance improvements. Goodrich recently flight tested their 3rd Generation Reconnaissance System on a Block 52 F-16 aircraft with first flight success and excellent results. This paper presents key highlights of the system and presents imaging results from flight test.
NASA Astrophysics Data System (ADS)
Eshach, Haim
2010-08-01
The starting point of the present research is the following question: since we live in an age that makes increasing use of visual representations of all sorts, is not the visual representation a learner constructs a window into his/her understanding of what is or is not being learned? Following this direction of inquiry, the present preliminary study introduces and evaluates a novel technique for pinpointing learners’ misconceptions, namely, one that has learners create and interpret their own photographs (CIP). 27 high-school students and 26 pre-service teacher trainees were asked to assume the role of textbook designers and create a display—photograph plus attached verbal explanation—which, in their opinion, best depicted Newton’s 3rd law. Subsequent analysis of the participants’ photographs yielded the following six misconception categories: 3rd law not depicted; 3rd law depicts a sequence of events; tendency to introduce irrelevant entities in explanations; the word ‘reaction’ used colloquially; tendency to restrict the application of the third law to dynamic situations; and informal explanations in which the word “force” is absent. The findings indicate that, indeed, the CIP method can be effectively employed to elicit, detect, and investigate learners’ misconceptions. The CIP method joins the growing efforts to utilize the yet relatively untapped potential of visual tools for science education purposes.
Einstein equation at singularities
NASA Astrophysics Data System (ADS)
Stoica, Ovidiu-Cristinel
2014-02-01
Einstein's equation is rewritten in an equivalent form, which remains valid at the singularities in some major cases. These cases include the Schwarzschild singularity, the Friedmann-Lemaître-Robertson-Walker Big Bang singularity, isotropic singularities, and a class of warped product singularities. This equation is constructed in terms of the Ricci part of the Riemann curvature (as the Kulkarni-Nomizu product between Einstein's equation and the metric tensor).
[Modern surgical treatment of breast cancer. 3rd Breast Cancer Consensus Conference].
Lázár, György; Bursics, Attila; Farsang, Zoltán; Harsányi, László; Kósa, Csaba; Maráz, Róbert; Mátrai, Zoltán; Paszt, Attila; Pavlovics, Gábor; Tamás, Róbert
2016-09-01
Therapy for breast cancer today is characterised by ever more precise diagnostic methods and ever more effective oncological treatments, a trend which will certainly continue into the future. Breast preservation and the application of oncoplastic principles are increasingly popular. A sentinel lymph node biopsy in the surgical treatment of the axilla is primary, with the indication for axillary block dissection (ABD) narrowing and radiation therapy becoming an alternative to ABD in certain cases. This publication summarises our recommendations on the surgical treatment of breast cancer based on the content of the 3rd Breast Cancer Consensus Conference and considering the latest international studies and professional recommendations. PMID:27644928
Johnson, S. L.
2016-01-01
The ability to visualize the real-time dynamics of atomic, magnetic, and electronic structure is widely recognized in many fields as a key element underpinning many important processes in chemistry, materials science, and biology. The need for an improved understanding of such processes becomes acute as energy conversion processes on fast time scales become increasingly relevant to problems in science and technology. This special issue, containing invited papers from participants at the 3rd International Conference on Ultrafast Structural Dynamics held June 10–12, 2015 in Zurich, Switzerland, discusses several recent developments in this area. PMID:27191008
NURSING EMERGING. ANA Nursing: Scope and Standards of Practice, (2015) 3rd Edition.
Mariano, Carla
2016-04-01
AHNA Past-President Carla Mariano recently had the privilege of serving on the American Nurses Association's (ANA) Nursing Scope and Standards Revision Workgroup. Representing the specialty practice of holistic nursing, Carla's presence within this workgroup contributed greatly to the inclusion of holistic principles and values throughout the new 2015 Nursing: Scope and Standards of Practice, 3rd edition, the foundational document that informs and guides professional nursing practice within the United States. This is a significant step forward for holistic nursing and an indicator of our growing influence as specialty practice. PMID:27305802
Johnson, S L
2016-03-01
The ability to visualize the real-time dynamics of atomic, magnetic, and electronic structure is widely recognized in many fields as a key element underpinning many important processes in chemistry, materials science, and biology. The need for an improved understanding of such processes becomes acute as energy conversion processes on fast time scales become increasingly relevant to problems in science and technology. This special issue, containing invited papers from participants at the 3rd International Conference on Ultrafast Structural Dynamics held June 10-12, 2015 in Zurich, Switzerland, discusses several recent developments in this area. PMID:27191008
Overview of the 3rd isirv-Antiviral Group Conference – advances in clinical management
Hurt, Aeron C; Hui, David S; Hay, Alan; Hayden, Frederick G
2015-01-01
This review highlights the main points which emerged from the presentations and discussions at the 3rd isirv-Antiviral Group Conference - advances in clinical management. The conference covered emerging and potentially pandemic influenza viruses and discussed novel/pre-licensure therapeutics and currently approved antivirals and vaccines for the control of influenza. Current data on approved and novel treatments for non-influenza respiratory viruses such as MERS-CoV, respiratory syncytial virus (RSV) and rhinoviruses and the challenges of treating immunocompromised patients with respiratory infections was highlighted. PMID:25399715
Extreme and Local 3rd Harmonic Response of Niobium (Nb) Superconductor
NASA Astrophysics Data System (ADS)
Oripov, Bakhrom; Tai, Tamin; Anlage, Steven
Superconducting Radio Frequency (SRF) cavities are being widely used in new generation particle accelerators. These SRF cavities are based on bulk Nb. Based on the needs of the SRF community to identify defects on Nb surfaces, a novel near-field magnetic microwave microscope was successfully built using a magnetic writer from a conventional magnetic recording hard-disk drive1. This magnetic writer can create an RF magnetic field, localized and strong enough to drive Nb into the vortex state. This probe enables us to locate defects through scanning and mapping of the local electrodynamic response in the multi-GHz frequency range. Recent measurements have shown that 3rd harmonic nonlinear response is far more sensitive to variations in input power and temperature then linear response, thus we mainly study the 3rd harmonic response. Moreover, the superconductor is usually the only source for nonlinear response in our setup, thus there is less chance of having noise or background signal. Understanding the mechanism responsible for this non-linear response is important for improving the performance of SRF cavities. Besides Nb we also study various other superconductors such as MgB2 and the cuprate Bi-Sr-Ca-Cu-O (BSCCO) for potential applications in SRF cavities. This work is funded by US Department of Energy through Grant # DE-SC0012036T and CNAM.
Treatment of 3rd molar-induced periodontal defects with guided tissue regeneration.
Oxford, G E; Quintero, G; Stuller, C B; Gher, M E
1997-07-01
Recent reports provide evidence of increased attachment levels when using guided tissue regeneration (GTR) techniques for the treatment of periodontal defects. Periodontal defects frequently occur at the distal aspect of mandibular 2nd molars which are next to mesioangular impacted 3rd molars that have oral communication. The purpose of this study was to determine whether the use of GTR can enhance probing attachment levels (PALs) following extraction of mesioangular impacted third molars. 12 patients with bilateral soft tissue impacted mandibular 3rd molars entered this split mouth study. After extractions, the previously exposed distal root surface of the 2nd molars were debrided. The defects on the randomly selected experimental sites were covered with expanded polytetraflouro-ethylene (e-PTFE) membrane and the tissue was replaced to cover the membrane. Membranes were removed after 6 weeks. Control sites were treated identically except no membrane was placed. GI, P1I, PD, PAL and BOP records were obtained at 0, 3 and 6 months. The use of barrier material did not provide statistically-significant differences in PAL when comparing experimental versus control sites. Nevertheless, PAL gain was consistently greater at 3 and 6 months when GTR techniques were used in sites with deep impactions. PMID:9226386
Schmiegelow, Christentze; Minja, Daniel; Oesterholt, Mayke; Pehrson, Caroline; Suhrs, Hannah Elena; Boström, Stéphanie; Lemnge, Martha; Magistrado, Pamela; Rasch, Vibeke; Nielsen, Birgitte Bruun; Lusingu, John; Theander, Thor G.
2013-01-01
Background Pregnancy associated malaria is associated with decreased birth weight, but in-utero evaluation of fetal growth alterations is rarely performed. The objective of this study was to investigate malaria induced changes in fetal growth during the 3rd trimester using trans-abdominal ultrasound. Methods An observational study of 876 pregnant women (398 primi- and secundigravidae and 478 multigravidae) was conducted in Tanzania. Fetal growth was monitored with ultrasound and screening for malaria was performed regularly. Birth weight and fetal weight were converted to z-scores, and fetal growth evaluated as fetal weight gain from the 26th week of pregnancy. Results Malaria infection only affected birth weight and fetal growth among primi- and secundigravid women. Forty-eight of the 398 primi- and secundigravid women had malaria during pregnancy causing a reduction in the newborns z-score of −0.50 (95% CI: −0.86, −0.13, P = 0.008, multiple linear regression). Fifty-eight percent (28/48) of the primi- and secundigravidae had malaria in the first half of pregnancy, but an effect on fetal growth was observed in the 3rd trimester with an OR of 4.89 for the fetal growth rate belonging to the lowest 25% in the population (95%CI: 2.03–11.79, P<0.001, multiple logistic regression). At an individual level, among the primi- and secundigravidae, 27% experienced alterations of fetal growth immediately after exposure but only for a short interval, 27% only late in pregnancy, 16.2% persistently from exposure until the end of pregnancy, and 29.7% had no alterations of fetal growth. Conclusions The effect of malaria infections was observed during the 3rd trimester, despite infections occurring much earlier in pregnancy, and different mechanisms might operate leading to different patterns of growth alterations. This study highlights the need for protection against malaria throughout pregnancy and the recognition that observed changes in fetal growth might be a
2010-01-01
The 3rd International Workshop on Insulin & Cancer was held on October 30-31, 2010 at the German Cancer Research Centre in Heidelberg/Germany. The topics followed-up the discussions of the previous workshops: possible differences in mitogenicity between natural insulin and genetically engineered insulin derivatives (insulin analogues), as shown by laboratory studies and epidemiologic studies alike; molecular studies on the links between metabolic and mitogenic effects of insulin, and of hyperinsulinaemia in particular; epidemiologic evidence of interferences between insulin and other hormones, particularly sex hormones, and obesity-associated cancer; the involvement of inflammatory cytokines produced by fat tissue in obesity-associated cancer; aspects of drug-design (binding drugs to albumin) and, last but not least, detection and investigation of circulating cancer cells. PMID:21176129
Chantelau, Ernst; Mayer, Doris
2010-01-01
The 3rd International Workshop on Insulin & Cancer was held on October 30-31, 2010 at the German Cancer Research Centre in Heidelberg/Germany. The topics followed-up the discussions of the previous workshops: possible differences in mitogenicity between natural insulin and genetically engineered insulin derivatives (insulin analogues), as shown by laboratory studies and epidemiologic studies alike; molecular studies on the links between metabolic and mitogenic effects of insulin, and of hyperinsulinaemia in particular; epidemiologic evidence of interferences between insulin and other hormones, particularly sex hormones, and obesity-associated cancer; the involvement of inflammatory cytokines produced by fat tissue in obesity-associated cancer; aspects of drug-design (binding drugs to albumin) and, last but not least, detection and investigation of circulating cancer cells.
Passive solar progress: a simplified guide to the 3rd national passive solar conference
Miller, H.; Howell, Y.; Richards, D.
1980-10-01
Some of the concepts and practices that have come to be known as passive solar heating and cooling are introduced, and a current picture of the field is presented. Much of the material presented is derived from papers given at the 3rd National Passive Solar Conference held in San Jose, California in January 1979 and sponsored by the US Department of Energy. Extracts and data from these papers have been integrated in the text with explanatory and descriptive material. In this way, it is attempted to present technical information in an introductory context. Topics include design considerations, passive and hybrid systems and applications, sizing methods and performance prediction, and implementation issues. A glossary is included. (WHK)
Dental health in antique population of Vinkovci - Cibalae in Croatia (3rd-5th century).
Peko, Dunja; Vodanović, Marin
2016-08-01
Roman city Cibalae (Vinkovci) - the birthplace of Roman emperors Valentinian I and Valens was a very well developed urban ares in the late antique what was evidenced by numerous archaeological findings. The aim of this paper is to get insight in dental health of antique population of Cibalae. One hundred individuals with 2041 teeth dated to 3rd - 5th century AD have been analyzed for caries, antemortem tooth loss, periapical diseases and tooth wear. Prevalence of antemortem tooth loss was 4.3% in males, 5.2% in females. Prevalence of caries per tooth was 8.4% in males, 7.0% in females. Compared to other Croatian antique sites, ancient inhabitants of Roman Cibalae had rather good dental health with low caries prevalence and no gender differences. Statistically significant difference was found between males in females in the prevalence of periapical lesions and degree of tooth wear. Periapical lesions were found only in males. PMID:27598951
John D. Rockefeller 3rd, statesman and founder of the Population Council.
Dunlop, J
2000-01-01
This article presents a profile of John D. Rockefeller 3rd, statesman and founder of the Population Council. It is noted that Rockefeller took a broad view of population control as a means to address poverty and economic development rather than as an end in itself. In 1952 he initiated the convocation of the Conference on Population Problems held in Williamsburg, Virginia. The discussion focused on food supply, industrial development, depletion of natural resources, and political instability resulting from unchecked population growth. In 1967, Rockefeller initiated, lobbied for, and finally achieved a World Leaders' Statement signed by 30 heads of state including US President Lyndon Johnson. The document drew attention to population growth as a world problem and engendered political support for family planning as a solution. After 3 years the Commission on Population Growth and the American Future was established, and Rockefeller was made its chairman. Several issues were debated, including more safer fertility control and the legalization of abortion.
Food: The Chemistry of Its Components, 3rd Edition (by T. P. Coultate)
NASA Astrophysics Data System (ADS)
Carandang, Rachelle; Ziegler, Greg
1998-02-01
Food: The Chemistry of Its Components, 3rd edition, by T. P. Coultate, is an excellent textbook in food chemistry for undergraduates. It is a concise version of the very detailed Food Chemistry by Fennema and similar to, but with advantages over, Mechanism and Theory in Food Chemistry by Wong and Principles of Food Chemistry by Deman. The book assumes knowledge of biochemistry and basic principles in organic chemistry, but presents very practical examples that allow the student to see the obvious link between theory and practice. The examples are described almost as if the author is performing a demonstration in a classvery vivid to the imagination. This is important because students are expected in the future to perform and put into practice their knowledge of food chemistry.
NASA Astrophysics Data System (ADS)
Kiwon, Kim; Li, Lu; Taehyun, Nam; Jouhyeon, Ahn
2010-05-01
The 3rd International Symposium on Functional Materials 2009 (ISFM 2009) and its preconference, Advances in Functional Materials 2009 (AFM 2009), were successfully held in the Republic of Korea from 15-18 June 2009 and in the People's Republic of China from 8-12 June 2009, respectively. The two conferences attracted over 300 oral and poster presentations from over 12 countries including Australia, Canada, China, Germany, Japan, India, Israel, Korea, The Netherlands, Thailand, the UK and the USA. In the two conferences, eight keynote lectures were delivered by S Miyazaki, S A Akbar, D J Singh, C Suryanarayana, M~Greenblatt, H Zhang, T Sato and J Ding. This topical issue of Physica Scripta contains papers presented at the ISFM 2009 and AFM 2009. Keyan Li from Dalian University, People's Republic of China, presents some empirical formulae to estimate the elastic moduli of rocksalt-, zincblende- and chalcopyrite-structured crystals, on the basis of electronegativities of bonded atoms in the crystallographic frame. Min-Jung Kim from Hanyang University, Korea, reports on the preparation and characterization of carboxyl functionalization of magnetite nanoparticles for oligonucleotide immobilization. F Yan from the National University of Singapore studies the fabrication of Bi(Fe0.5Sc0.5)O3-PbTiO3 (BSF-PT) thin films by pulsed laser deposition, and the enhanced magnetic moment with respect to BiFeO3-PbTiO3. Dong-Gil Lee from Pusan National University, Korea, reports on the sterilization of enteropathogenic Escherichia coli using nanofiber TiO2 films prepared by the electrostatic spray method. Sang-Eun Park from the Korea Institute of Science and Technology reports on the study of encapsulated Fe3O4 nanoparticles with a silica thin layer with a reversible capacity of about 363 mAhg-1. Other researchers report on many other exiting achievements in the fields of ferromagnetic materials, magneto-optical materials, thermoelectric materials, shape memory materials, fuel-cell and
Simulation of robustness of a new e-beam column with the 3 rd-order imaging technique
NASA Astrophysics Data System (ADS)
Takeya, K.; Fuse, T.; Kinoshita, H.; Parker, N. William
2008-03-01
We are now investigating a new concept column with the 3 rd-order imaging technique, in order to obtain fine resolution and high current density beams for electron beam direct writing (EBDW) suitable for below 32nm technology nodes. From the first experimental verification, it is found that the 3 rd-order imaging has a benefit of increasing the beam current compared with conventional Gaussian beam without any beam blurring. However, in order to realize such a column which can work stably in the sub 32nm technology node generations, it is important to clarify how robust the 3 rd-order imaging is against the mechanical tolerances in column manufacturing. This paper describes the tolerance analysis for errors of column manufacturing by simulation. The column has an electron gun with small virtual source and two (Gun and Main) lenses. A patterned beam defining aperture, which enables the 3 rd-order imaging, is set between the 1 st and the 2 nd lenses. The influences of errors such as concentricity, offset and tilt between optical parts on the beam shape, beam current density distribution, and beam edge acuity on a wafer is analyzed for this column. According to these results, the 3 rd-order imaging appears to have sufficiently large allowance compared to the error budget for column manufacturing required in the sub 32nm technology node patterning.
Singularities and Quantum Gravity
NASA Astrophysics Data System (ADS)
Bojowald, Martin
2007-06-01
Although there is general agreement that a removal of classical gravitational singularities is not only a crucial conceptual test of any approach to quantum gravity but also a prerequisite for any fundamental theory, the precise criteria for non-singular behavior are often unclear or controversial. Often, only special types of singularities such as the curvature singularities found in isotropic cosmological models are discussed and it is far from clear what this implies for the very general singularities that arise according to the singularity theorems of general relativity. In these lectures we present an overview of the current status of singularities in classical and quantum gravity, starting with a review and interpretation of the classical singularity theorems. This suggests possible routes for quantum gravity to evade the devastating conclusion of the theorems by different means, including modified dynamics or modified geometrical structures underlying quantum gravity. The latter is most clearly present in canonical quantizations which are discussed in more detail. Finally, the results are used to propose a general scheme of singularity removal, quantum hyperbolicity, to show cases where it is realized and to derive intuitive semiclassical pictures of cosmological bounces.
On singular and sincerely singular compact patterns
NASA Astrophysics Data System (ADS)
Rosenau, Philip; Zilburg, Alon
2016-08-01
A third order dispersive equation ut +(um)x +1/b[ua∇2ub]x = 0 is used to explore two very different classes of compact patterns. In the first, the prevailing singularity at the edge induces traveling compactons, solitary waves with a compact support. In the second, the singularity induced at the perimeter of the initial excitation, entraps the dynamics within the domain's interior (nonetheless, certain very singular excitations may escape it). Here, overlapping compactons undergo interaction which may result in an interchange of their positions, or form other structures, all confined within their initial support. We conjecture, and affirm it empirically, that whenever the system admits more than one type of compactons, only the least singular compactons may be evolutionary. The entrapment due to singularities is also unfolded and confirmed numerically in a class of diffusive equations ut =uk∇2un with k > 1 and n > 0 with excitations entrapped within their initial support observed to converge toward a space-time separable structure. A similar effect is also found in a class of nonlinear Klein-Gordon Equations.
TEC obtained from 3rd Stokes parameter for improved quality of SMOS salinity retrieval
NASA Astrophysics Data System (ADS)
Vergely, Jean-Luc; Waldteufel, Philippe; Boutin, Jacqueline; Yin, Xiaobin; Spurgeon, Paul
2014-05-01
While SMOS was designed with full polarimetric capability, the 3rd Stokes parameter information has not been introduced so far in the data processing. The analysis reported in the present contribution proposes to estimate from this information the total ionospheric electron content (TEC). Indeed the Faraday effect generated by the ionospheric electrons on the path from Earth to satellite is believed to be responsible for large uncertainties in the evening half-orbits (circa 06 PM local time) when the ionospheric content is close to its diurnal maximum. It is shown that the 3rd Stokes parameter exhibits a maximal sensitivity to TEC in a restricted area located at the front of the SMOS 2D field of view. However, since the Faraday angle depends on the scalar product between line-of-sight and magnetic field vectors, a latitudinal zone is found where this sensitivity vanishes. This zone occurs around 15° N a latitude nearly invariant with longitude around the Earth. Accordingly it is possible, when carrying out the TEC estimation over a descending half-orbit, to isolate over this "blind zone" the so-called "Ocean Target Transformation" parameter, which aims at correcting for pixel dependent biases. TEC maps obtained in this way compare favorably with maps built from GPS measurements, which have been introduced so far in the SMOS processing chain as auxiliary data. The space resolution is somewhat improved, allowing a better selection of the relevant electron content in zones exhibiting large horizontal TEC gradients. In a latter step, based on the TEC maps, it becomes possible to recompute the OTT correction for those brightness temperature components to be used as input in the salinity retrieval. Then the additional information impacts the salinity retrieval both directly (as the quality of the TEC auxiliary data is improved) and indirectly (as the empirical OTT correction is no longer contaminated by spurious Faraday rotation effects). The respective contributions of
ERIC Educational Resources Information Center
Nyhan, Paul
2011-01-01
The New School Foundation was not born from a commission, legislative mandate, research project, think tank, or even the mind of a leading education scholar. One of Washington state's pioneering PreK-3rd initiatives began as the brainchild of a wealthy Seattle businessman, Stuart Sloan, 20 years ago. The New School Foundation and its ideas were…
Effects of notetaking instruction on 3rd grade student's science learning and notetaking behavior
NASA Astrophysics Data System (ADS)
Lee, Pai-Lin
The research examined effects of notetaking instruction on elementary-aged students' ability to recall science information and notetaking behavior. Classes of 3rd grade students were randomly assigned to three treatment conditions, strategic notetaking, partial strategic notetaking, and control, for 4 training sessions. The effects of the notetaking instruction were measured by their performances on a test on science information taught during the training, a long-term free recall of the information, and number of information units recalled with or without cues. Students' prior science achievement was used to group students into two levels (high vs. low) and functioned as another independent variable in analysis. Results indicated significant treatment effect on cued and non-cued recall of the information units in favor of the strategy instruction groups. Students with higher prior achievement in science performed better on cued recall and long-term free recall of information. The results suggest that students as young as at the third grade can be instructed to develop the ability of notetaking that promotes their learning.
NASA Astrophysics Data System (ADS)
Zastavker, Yevgeniya V.
2009-03-01
The 3^rd International Conference on Women in Physics (ICWIP), held in Seoul, Korea, in October 2008, brought together 300 participants from 57 countries, including a diverse 22-member U.S. Delegation, for a 3-day summit of stimulating discussions, thought-provoking presentations, inspirational posters, and networking. Held under the auspices of the Working Group on Women in Physics of the International Union of Pure and Applied Physics (IUPAP), this meeting built on the successes of the 1^st (Paris, 2002) and 2^nd (Rio de Janeiro, 2005) Conferences and further clarified the importance of diversifying the field of physics worldwide. Although considerable progress has been made since 2002, it was clear that the global scientific workforce is still under-utilizing a large percentage of the available female talent pool. If human society is to benefit to its fullest from various contributions that the field of physics can offer in addressing global issues of economic crisis, energy, environment, water, health, poverty, and hunger, women of all races and nationalities need to become fully included and engaged in the national and international physical community. To address these and many other issues, the ICWIP unanimously approved a five-part resolution to IUPAP recommending actions to promote the recruitment, retention, and advancement of women in physics and related fields.
Measuring the cascade rate in anisotropic turbulence through 3rd order structure functions.
NASA Astrophysics Data System (ADS)
Verdini, Andrea; Landi, Simone; Hellinger, Petr
2014-05-01
We employ the Von-Karman-Howart-Yaglom-Politano-Poquet (KHYPP)law, to compute the cascade rate by means of 3rd order structure functions in homogeneous, forced, DNS at high resolution. We consider first the isotropic case (no guide field) and verify that the cascade rate is consistent with the dissipation rate. Then we consider an anisotropic case (with guide field) for which the isotropic KHYPP law does not apply. We compute the parallel and perpendicular cascade rates and find that the latter basically accounts for the total dissipation rate, as expected for anisotropic turbulence. Also, the cascade rate derived from the isotropic law is found to be a good approximation for the total cascade rate. Recent works have shown that the hypothesis of stationary turbulence must be probably relaxed in the solar wind. We present preliminary results on the measure of the cascade rate in the expanding solar wind, obtained with DNS of MHD turbulence in the expanding box model. Such model incorporates the basic physic of expansion thus inducing anisotropies driven by both the magnetic field and expansion, along with an energy decrease due to the conservation of linear invariants (angular momentum and magnetic flux). The correction due to non-stationary conditions is found to be important and to become negligible only at small scales, thus suggesting that solar wind measurements over- estimate the actual cascade rate.
Measurement and correction of the 3rd order resonance in the Tevatron
Schmidt, F.; Alexahin, Y.; Lebedev, V.; Still, D.; Valishev, A.; /Fermilab
2006-06-01
At Fermilab Tevatron BPM system has been recently upgraded resulting much better accuracy of beam position measurements and improvements of data acquisition for turn-by-turn measurements. That allows one to record the beam position at each turn for 8000 turns for all BPMs (118 in each plane) with accuracy of about 10-20 {micro}m. In the last decade a harmonic analysis tool has been developed at CERN that allows relating each FFT line derived from the BPM data with a particular non-linear resonance in the machine. In fact, one can even detect the longitudinal position of the sources of these resonances. Experiments have been performed at the Tevatron in which beams have been kicked to various amplitudes to analyze the 3rd order resonance. It was possible to address this rather large resonance to some regular machine sextupoles. An alternative sextupole scheme allowed the suppression of this resonance by a good factor of 2. Lastly, the experimental data are compared with model calculations.
SESAME-A 3rd Generation Synchrotron Light Source for the Middle East
NASA Astrophysics Data System (ADS)
Winick, Herman
2010-02-01
Developed under the auspices of UNESCO and modeled on CERN, SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) is an international research center in construction in Jordan. It will enable world class research by scientists from the region, reversing the brain drain. It will also build bridges between diverse societies, contributing to a culture of peace through international cooperation in science. The centerpiece is a synchrotron light source originating from BESSY I, a gift by Germany. The upgraded machine, a 2.5 GeV 3rd Generation Light Source (133m circumference, 26nm-rad emittance and 12 places for insertion devices), will provide light from infra-red to hard X-rays, offering excellent opportunities to train local scientists and attract those working abroad to return. The SESAME Council meets twice each year and presently has nine Members (Bahrain, Cyprus, Egypt, Iran, Israel, Jordan, Pakistan, Palestinian Authority, Turkey). Members have responsibility for the project and provide the annual operations budget (1.5M US dollars in 2009, expected to rise to about 5M when operation starts in 2012-13). Jordan provided the site, building, and infrastructure. A staff of 20 is installing the 0.8 GeV BESSY I injection system. The facility will have the capacity to serve 30 or more experiments operating simultaneously. See www.sesame.org.jo )
NASA Astrophysics Data System (ADS)
Droznin, V. A.; Kiryukhin, A. V.; Muraviev, J. D.
2007-12-01
Since 1990 cycling characteristics of five geysers (Maly, Bolshoy, Shel, Velican, Troynoy) were contentiously monitoring using automatic telemetric system (V A Drosnin, http://www.ch0103.emsd.iks.ru/ ). The most powerful geyser Velikan erupted steam clouds at 300 m height. 1:20 UTC June 3-rd, 2007 lower basin of the Geysers Valley was in a few minutes buried under 10 mln m3 of mud, debris, and blocks of rocks. Some indications were found, that landslide triggered by steam eruption in the upstream area of Vodopadny creek. As a result of this three famous geysers (Pervenets, Sakharny,Troynoy) located at lower elevations were sealed under 10-30 m thick caprock as well as Vodopadny hot creek, a rock dumb trap Geysernaya river and lifted water into 20 m deep lake, which flooded three famous geysers (Conus, Bolshoy and Maly) terminating their cycling activity. Nevertheless Bolshoy and Maly activity continues in a form of discharge of water circulated in the former geysers channels and a clear plume at a lake surface above exits observed. Shortly after landslide continuous monitoring of the cycling characteristics of the upper basin geysers, including Velikan and lake level, accomplished by temperature loggers - restarted. There are some indications time periods of the geysers cycling decrease.
Visual, Critical, and Scientific Thinking Dispositions in a 3rd Grade Science Classroom
NASA Astrophysics Data System (ADS)
Foss, Stacy
Many American students leave school without the required 21st century critical thinking skills. This qualitative case study, based on the theoretical concepts of Facione, Arheim, and Vygotsky, explored the development of thinking dispositions through the arts in science on the development of scientific thinking skills when used as a conceptual thinking routine in a rural 3rd grade classroom. Research questions examined the disposition to think critically through the arts in science and focused on the perceptions and experiences of 25 students with the Visual Thinking Strategy (VTS) process. Data were collected from classroom observations (n = 10), student interviews (n = 25), teacher interviews ( n = 1), a focus group discussion (n = 3), and artifacts of student work (n = 25); these data included perceptions of VTS, school culture, and classroom characteristics. An inductive analysis of qualitative data resulted in several emergent themes regarding disposition development and students generating questions while increasing affective motivation. The most prevalent dispositions were open-mindedness, the truth-seeking disposition, the analytical disposition, and the systematicity disposition. The findings about the teachers indicated that VTS questions in science supported "gradual release of responsibility", the internalization of process skills and vocabulary, and argumentation. This case study offers descriptive research that links visual arts inquiry and the development of critical thinking dispositions in science at the elementary level. A science curriculum could be developed, that emphasizes the development of thinking dispositions through the arts in science, which in turn, could impact the professional development of teachers and learning outcomes for students.
Appenroth, Klaus-J; Sree, K Sowjanya; Fakhoorian, Tamra; Lam, Eric
2015-12-01
Duckweed, flowering plants in the Lemnaceae family, comprises the smallest angiosperms in the plant kingdom. They have some of the fastest biomass accumulation rates reported to date for plants and have the demonstrated ability to thrive on wastewater rich in dissolved organic compounds and thus could help to remediated polluted water resources and prevents eutrophication. With a high quality genome sequence now available and increased commercial interest worldwide to develop duckweed biomass for renewables such as protein and fuel, the 3rd International Duckweed Conference convened at Kyoto, Japan, in July of 2015, to update the community of duckweed researchers and developers on the progress in the field. In addition to sharing results and ideas, the conference also provided ample opportunities for new-comers as well as established workers in the field to network and create new aliances. We hope this meeting summary will also help to disseminate the key advances and observations that have been presented in this conference to the broader plant biology community in order to encourage increased cross-fertilization of ideas and technologies. PMID:26506824
Appenroth, Klaus-J; Sree, K Sowjanya; Fakhoorian, Tamra; Lam, Eric
2015-12-01
Duckweed, flowering plants in the Lemnaceae family, comprises the smallest angiosperms in the plant kingdom. They have some of the fastest biomass accumulation rates reported to date for plants and have the demonstrated ability to thrive on wastewater rich in dissolved organic compounds and thus could help to remediated polluted water resources and prevents eutrophication. With a high quality genome sequence now available and increased commercial interest worldwide to develop duckweed biomass for renewables such as protein and fuel, the 3rd International Duckweed Conference convened at Kyoto, Japan, in July of 2015, to update the community of duckweed researchers and developers on the progress in the field. In addition to sharing results and ideas, the conference also provided ample opportunities for new-comers as well as established workers in the field to network and create new aliances. We hope this meeting summary will also help to disseminate the key advances and observations that have been presented in this conference to the broader plant biology community in order to encourage increased cross-fertilization of ideas and technologies.
NASA Astrophysics Data System (ADS)
Lumban Gaol, Ford; Webb, Jeff; Ding, Jun
2015-05-01
The 3rd International Conference on Manufacturing, Optimization, Industrial and Material Engineering (MOIME 2015) was held at the Sheraton Kuta, Bali, Indonesia, from 28 - 29 March 2015. The MOIME 2015 conference is aimed to bring together researchers, engineers and scientists in the domain of interest from around the world. MOIME 2015 is placed on promoting interaction between the theoretical, experimental, and applied communities, so that a high level exchange is achieved in new and emerging areas within Material Engineering, Industrial Engineering and all areas that relate to Optimization. We would like to express our sincere gratitude to all in the Technical Program Committee who have reviewed the papers and developed a very interesting Conference Program, as well as the invited and plenary speakers. This year, we received 99 papers and after rigorous review, 24 papers were accepted. The participants come from eight countries. There were four parallel sessions and two invited speakers. It is an honour to present this volume of IOP Conference Series: Materials Science and Engineering (MSE) and we deeply thank the authors for their enthusiastic and high-grade contributions. Finally, we would like to thank the conference chairmen, the members of the steering committee, the organizing committee, the organizing secretariat and the financial support from the conference sponsors that allowed the success of MOIME 2015. The Editors of the MOIME 2015 Proceedings Dr. Ford Lumban Gaol Jeff Webb, Ph.D Prof. Jun DING, Ph.D
Exploiting stem cell therapy: the 3rd meeting of stem cell research Italy.
Di Bernardo, Giovanni; Piva, Roberta; Giordano, Antonio; Galderisi, Umberto
2013-04-01
The study of stem cells is one of the most exciting areas of contemporary biomedical research. During the 3rd Joint Meeting of Stem Cell Research Italy (June 2012, Ferrara, Italy), scientists from different multidisciplinary areas explored new frontiers of basic and applied stem cell research with key lectures and oral presentations. There was a public debate on ethics during the opening ceremony, specifically on the limits and potentialities of adult and embryonic stem cells. Some scientists presented basic research data showing evolutionary aspects, which could be of interest in understanding specific biological phenomena. Others focused on "dangerous liaisons" between gene transfer vectors and the human genome. Some speakers provided insight into current stem cell therapies, such as those involving human epithelial stem cells for treatment of skin diseases. Other researchers presented data on close-to-therapy findings, such as the use of mesenchymal stem cells in brain repair. Of note, during the meeting, spotlights were focused on major issues that have to be considered for GMP stem cell production for cell therapy. In "Meet the Expert" sessions, specialists presented innovative technologies such as a next-generation sequencing system. Finally, the meeting provided an excellent opportunity for young scientists to show their findings, and to discuss with each other and with internationally recognized experts.
Singular finite element methods
NASA Technical Reports Server (NTRS)
Fix, George J.
1987-01-01
Singularities which arise in the solution to elliptic systems are often of great technological importance. This is certainly the case in models of fracture of structures. A survey of the ways singularities are modeled is presented with special emphasis on the effects due to nonlinearities.
ERIC Educational Resources Information Center
Jordan, Michelle E.; Santori, Diane
2015-01-01
This multisite study investigates dialogic literacy events that revolved around narrative and informational texts in two 3rd-grade classrooms. The authors offer a metaphor of musical improvisation to contemplate dialogic literacy events as part of the repertoire of teaching and learning experiences. In literacy learning, where there is much…
ERIC Educational Resources Information Center
Kao, Grace S.; Thomas, Hillary M.
2010-01-01
"Conners 3rd Edition" is the most updated version of a series of measures for assessing attention deficit hyperactivity disorder (ADHD) and common comorbid problems/disorders in children and adolescents ranging from 6 to 18 years of age. Related problems that the test helps assess include executive dysfunction, learning problems, aggression, and…
Predicting 3rd Grade and 10th Grade FCAT Success for 2006-07. Research Brief. Volume 0601
ERIC Educational Resources Information Center
Froman, Terry; Rubiera, Vilma
2006-01-01
For the past few years the Florida School Code has set the Florida Comprehensive Assessment Test (FCAT) performance requirements for promotion of 3rd graders and graduation for 10th graders. Grade 3 students who do not score at level 2 or higher on the FCAT SSS Reading must be retained unless exempted for special circumstances. Grade 10 students…
Predicting 3rd Grade and 10th Grade FCAT Success for 2007-08. Research Brief. Volume 0702
ERIC Educational Resources Information Center
Froman, Terry; Rubiera, Vilma
2008-01-01
For the past few years the Florida School Code has set the Florida Comprehensive Assessment Test (FCAT) performance requirements for promotion of 3rd graders and graduation for 10 graders. Grade 3 students who do not score at level 2 or higher on the FCAT SSS Reading must be retained unless exempted for special circumstances. Grade 10 students…
ERIC Educational Resources Information Center
Galvan, Richard
2011-01-01
The purpose of this study was to describe the psychosocial and identity challenges of 3rd generation and beyond U.S.-born (3GAB-USB) Mexican heritage college students. Alvarez (1973) has written about the psychosocial impact "hybridity" can have on a U.S.- born (USB) Mexican individual who incorporates two distinct cultures (American and Mexican)…
Iron metabolism in African American women during the 2nd and 3rd trimester of a high-risk pregnancy
Technology Transfer Automated Retrieval System (TEKTRAN)
Objective: To examine iron metabolism during the 2nd and 3rd trimester in African American women classified as a high-risk pregnancy. Design: Longitudinal. Setting: Large, university-based, urban Midwestern medical center. Participants: Convenience sample of 47 African American women classified a...
Iowa Acceleration Scale Manual: A Guide for Whole-Grade Acceleration K-8. (3rd Edition, Manual)
ERIC Educational Resources Information Center
Assouline, Susan G.; Colangelo, Nicholas; Lupkowski-Shoplik, Ann; Forstadt, Leslie; Lipscomb, Jonathon
2009-01-01
Feedback from years of nationwide use has resulted in a 3rd Edition of this unique, systematic, and objective guide to considering and implementing academic acceleration. Developed and tested by the Belin-Blank Center at the University of Iowa, the IAS ensures that acceleration decisions are systematic, thoughtful, well reasoned, and defensible.…
A Program Evaluation of ClassScape Used in 3rd Grade Classes in a Rural County in North Carolina
ERIC Educational Resources Information Center
Rogers, Misha Neely
2012-01-01
The research study will examine the impact of using the ClassScape program and targeted interventions on 3rd grade reading levels of performance. The conceptual and theoretical framework for the study suggests the need to connect formative, benchmark, and summative assessments in North Carolina. Furthermore, the review of the literature will…
ERIC Educational Resources Information Center
Edmundson, Margaret, Ed.
1993-01-01
This PIALA 1993 Proceedings contains many of the papers presented at the 3rd annual conference of the Pacific Islands Association of Libraries and Archives. This publication is the first time papers from this Micronesian regional library and archives conference have ever been published. The conference addressed various topics of interest to…
Singularities and Closed String Tachyons
Silverstein, Eva; /SLAC /Stanford U., Phys. Dept.
2006-03-17
A basic problem in gravitational physics is the resolution of spacetime singularities where general relativity breaks down. The simplest such singularities are conical singularities arising from orbifold identifications of flat space, and the most challenging are spacelike singularities inside black holes (and in cosmology). Topology changing processes also require evolution through classically singular spacetimes. I briefly review how a phase of closed string tachyon condensate replaces, and helps to resolve, basic singularities of each of these types. Finally I discuss some interesting features of singularities arising in the small volume limit of compact negatively curved spaces and the emerging zoology of spacelike singularities.
NASA Astrophysics Data System (ADS)
Refsnes, Magne, Prof; Gusev, Alexander, Dr; Godymchuk, Anna, Dr; Bogdan, Anna
2015-11-01
The 3rd International Youth Conference "Interdisciplinary Problems of Nanotechnology, Biomedicine and Nanotoxicology" (Nanobiotech2015) was held on 21-22 May 2015 in Tambov, Russia, and was jointly organized by Tambov Derzhavin State University (Russia), the Norwegian Institute of Public Health (Norway), the National University of Science and Technology MISiS (Russia), Tomsk Polytechnic University (Russia) and Tomsk State University. The conference gathered experienced and young researchers, post-docs and students, working in the fieldof nanotechnologies, nanomedicine, nano(eco)toxicology and risk assessment of nanomaterials, in order to facilitate the aggregation and sharing of interests and results for better collaboration and visibility of activity. The goal of Nanobiotech2015 was to bring researchers and practitioners together to share the latest knowledge on nanotechnology-specific risks to occupational and environmental health and assessing how to reduce these potential risks. The main objective of the conference is to identify, systematize and solve current scientific problems inthe sphere of nanobiotechnologies, nanomedicine and nanotoxicology, in order to join forces todetermine prospective areas and compose working groups of interested co-workers for carrying out interdisciplinary research projects. The topics of Nanobiotech2015 were: (1) Nanotechnologies in pharmaceutics and medicine; (2) Sources and mechanisms of nanoparticle release into the environment; (3) Ecological and biological effects of nanoparticles; (4) (Eco)toxicology of nanomaterials; (5) Methods for detection of nanoparticles in the environment and in biological objects; and (6) Physico-chemical properties of nanoparticles in the environment. We want to thank the Organizing Committee, the universities and sponsors supporting the conference,and everyone who contributed to the organization of this meeting, for their contribution towards the conference and for their contributions to these
NASA Astrophysics Data System (ADS)
Petrick, Lauren; Dubowski, Yael
2010-05-01
Tobacco smoking is well known as a significant source of primary indoor air pollutants. However, only recently has it been recognized that the impact of Tobacco smoking may continue even after the cigarette has been extinguished (i.e., third hand smoke) due to the effect of indoor surfaces. These surfaces may affect the fate of tobacco smoke in the form of secondary reactions and pollutants, including secondary organic aerosol (SOA) formation. Fourier Transform Infrared spectrometry with Attenuated Total Reflection (FTIR-ATR) in tandem with a Scanning Mobility Particle Sizing (SMPS) system was used to monitor the ozonation of cellulose sorbed nicotine and resulting SOA formation. SOA formation began at onset of ozone introduction ([O3] = 60 ± 5 ppb) with a size distribution of dp ≤ 25 nm, and was determined to be a result of heterogeneous reaction (opposed to homogeneous). SOA yield from reacted surface nicotine was on the order of 10 %. Simultaneous to SOA monitoring, FTIR-ATR spectra showed surface changes in the nicotine film as the reaction progressed, revealing a pseudo first-order surface reaction rate of 0.0026 ± 0.0008 min-1. Identified surface oxidation products included: cotinine, myosmine, methylnicotinamide and nicotyrine. Surface reaction rate was found to be partially inhibited at high relative humidity. Given the toxicity of some of the identified products (e.g., cotinine has shown potential mutagenicity and teratogenicity) and that small particles may contribute to adverse health effects, the present study indicates that exposure to 3rd hand smoke ozonation products may pose additional health risks.
Goswami, Rituparno; Joshi, Pankaj S.; Vaz, Cenalo; Witten, Louis
2004-10-15
We construct a class of spherically symmetric collapse models in which a naked singularity may develop as the end state of collapse. The matter distribution considered has negative radial and tangential pressures, but the weak energy condition is obeyed throughout. The singularity forms at the center of the collapsing cloud and continues to be visible for a finite time. The duration of visibility depends on the nature of energy distribution. Hence the causal structure of the resulting singularity depends on the nature of the mass function chosen for the cloud. We present a general model in which the naked singularity formed is timelike, neither pointlike nor null. Our work represents a step toward clarifying the necessary conditions for the validity of the Cosmic Censorship Conjecture.
NASA Astrophysics Data System (ADS)
Ling, Eric
The big bang theory is a model of the universe which makes the striking prediction that the universe began a finite amount of time in the past at the so called "Big Bang singularity." We explore the physical and mathematical justification of this surprising result. After laying down the framework of the universe as a spacetime manifold, we combine physical observations with global symmetrical assumptions to deduce the FRW cosmological models which predict a big bang singularity. Next we prove a couple theorems due to Stephen Hawking which show that the big bang singularity exists even if one removes the global symmetrical assumptions. Lastly, we investigate the conditions one needs to impose on a spacetime if one wishes to avoid a singularity. The ideas and concepts used here to study spacetimes are similar to those used to study Riemannian manifolds, therefore we compare and contrast the two geometries throughout.
Spacetime Singularities: Recent Developments
NASA Astrophysics Data System (ADS)
Uggla, Claes
2013-03-01
Recent developments concerning oscillatory spacelike singularities in general relativity are taking place on two fronts. The first treats generic singularities in spatially homogeneous cosmology, most notably Bianchi types VIII and IX. The second deals with generic oscillatory singularities in inhomogeneous cosmologies, especially those with two commuting spacelike Killing vectors. This paper describes recent progress in these two areas: in the spatially homogeneous case, focus is on mathematically rigorous results, while analytical and numerical results concerning generic behavior and so-called recurring spike formation are the main topics in the inhomogeneous case. Unifying themes are connections between asymptotic behavior, hierarchical structures and solution generating techniques, which provide hints for a link between the nature of generic singularities and a hierarchy of hidden asymptotic symmetries.
NASA Astrophysics Data System (ADS)
Morrison, David R.; Taylor, Washington
2012-01-01
We analyze the structure of matter representations arising from codimension two singularities in F-theory, focusing on gauge groups SU( N). We give a detailed local description of the geometry associated with several types of singularities and the associated matter representations. We also construct global F-theory models for 6D and 4D theories containing these matter representations. The codimension two singularities encountered include examples where the apparent Kodaira singularity type does not need to be completely resolved to produce a smooth Calabi-Yau, examples with rank enhancement by more than one, and examples where the 7-brane configuration is singular. We identify novel phase transitions, in some of which the gauge group remains fixed but the singularity type and associated matter content change along a continuous family of theories. Global analysis of 6D theories on ℙ2 with 7-branes wrapped on curves of small degree reproduces the range of 6D supergravity theories identified through anomaly cancellation and other consistency conditions. Analogous 4D models are constructed through global F-theory compactifications on ℙ3, and have a similar pattern of SU( N) matter content. This leads to a constraint on the matter content of a limited class of 4D supergravity theories containing SU( N) as a local factor of the gauge group.
ic-cmtp3: 3rd International Conference on Competitive Materials and Technology Processes
NASA Astrophysics Data System (ADS)
2016-04-01
Competitiveness is one of the most important factors in our lives and it plays a key role in the efficiency both of organizations and societies. The more scientifically advanced and prepared organizations develop more competitive materials with better physical, chemical, and biological properties, and the leading companies apply more competitive equipment and technological processes. The aims of the 3rd International Conference on Competitive Materials and Technology Processes (ic-cmtp3), and the 1st International Symposium on Innovative Carbons and Carbon Based Materials (is-icbm1) and the 1st International Symposium on Innovative Construction Materials (is-icm1) organized alongside are the following: —Promote new methods and results of scientific research in the fields of material, biological, environmental and technological sciences; —Exchange information between the theoretical and applied sciences as well as technical and technological implementations; —Promote communication and collaboration between the scientists, researchers and engineers of different nations, countries and continents. Among the major fields of interest are advanced and innovative materials with competitive characteristics, including mechanical, physical, chemical, biological, medical and thermal, properties and extreme dynamic strength. Their crystalline, nano - and micro-structures, phase transformations as well as details of their technological processes, tests and measurements are also in the focus of the ic-cmtp3 conference and the is-scbm1 and is-icm1 symposia. Multidisciplinary applications of material science and the technological problems encountered in sectors like ceramics, glasses, thin films, aerospace, automotive and marine industries, electronics, energy, construction materials, medicine, biosciences and environmental sciences are of particular interest. In accordance with the program of the ic-cmtp3 conference and is-icbm1 and is-icm1 symposia we have received more
PREFACE: 3rd International Workshop on "State of the Art in Nuclear Cluster Physics"
NASA Astrophysics Data System (ADS)
Yamada, Taiichi; Kanada-En'yo, Yoshiko
2014-12-01
The 3rd International Workshop on "State of the Art in Nuclear Cluster Physics"(SOTANCP3) was held at KGU Kannai Media Center, Kanto Gakuin University, Yokohama, Japan, from May 26 to 30, 2014. Yokohama is the second largest city in Japan, about 25 km southeast of Tokyo. The first workshop of the series was held in Strasbourg, France, in 2008 and the second one was in Brussels, Belgium, in 2010. The purpose of SOTANCP3 was to discuss the present status and future perspectives of the nuclear cluster physics. The following nine topics were selected in order to cover most of the scientific programme and highlight an area where new ideas have emerged over recent years: (1) Cluster structures and many-body correlations in stable and unstable nuclei (2) Clustering aspects of nuclear reactions and resonances (3) Alpha condensates and analogy with condensed matter approaches (4) Role of tensor force in cluster physics and ab initio approaches (5) Clustering in hypernuclei (6) Nuclear fission, superheavy nuclei, and cluster decay (7) Cluster physics and nuclear astrophysics (8) Clustering in nuclear matter and neutron stars (9) Clustering in hadron and atomic physics There were 122 participants, including 53 from 17 foreign countries. In addition to invited talks, we had many talks selected from contributed papers. There were plenary, parallel, and poster sessions. Poster contributions were also presented as four-minute talks in parallel sessions. This proceedings contains the papers presented in invited and selected talks together with those presented in poster sessions. We would like to express our gratitude to the members of the International Advisory Committee and those of the Organizing Committee for their efforts which made this workshop successful. In particular we would like to present our great thanks to Drs. Y. Funaki, W. Horiuchi, N. Itagaki, M. Kimura, T. Myo, and T. Yoshida. We would like also to thank the following organizations for their sponsors: RCNP
NASA Astrophysics Data System (ADS)
Tayurskii, Dmitrii; Abe, Sumiyoshi; Alexandre Wang, Q.
2012-11-01
The 3rd International Workshop on Statistical Physics and Mathematics for Complex Systems (SPMCS2012) was held between 25-30 August at Kazan (Volga Region) Federal University, Kazan, Russian Federation. This workshop was jointly organized by Kazan Federal University and Institut Supérieur des Matériaux et Mécaniques Avancées (ISMANS), France. The series of SPMCS workshops was created in 2008 with the aim to be an interdisciplinary incubator for the worldwide exchange of innovative ideas and information about the latest results. The first workshop was held at ISMANS, Le Mans (France) in 2008, and the third at Huazhong Normal University, Wuhan (China) in 2010. At SPMCS2012, we wished to bring together a broad community of researchers from the different branches of the rapidly developing complexity science to discuss the fundamental theoretical challenges (geometry/topology, number theory, statistical physics, dynamical systems, etc) as well as experimental and applied aspects of many practical problems (condensed matter, disordered systems, financial markets, chemistry, biology, geoscience, etc). The program of SPMCS2012 was prepared based on three categories: (i) physical and mathematical studies (quantum mechanics, generalized nonequilibrium thermodynamics, nonlinear dynamics, condensed matter physics, nanoscience); (ii) natural complex systems (physical, geophysical, chemical and biological); (iii) social, economical, political agent systems and man-made complex systems. The conference attracted 64 participants from 10 countries. There were 10 invited lectures, 12 invited talks and 28 regular oral talks in the morning and afternoon sessions. The book of Abstracts is available from the conference website (http://www.ksu.ru/conf/spmcs2012/?id=3). A round table was also held, the topic of which was 'Recent and Anticipated Future Progress in Science of Complexity', discussing a variety of questions and opinions important for the understanding of the concept of
SESAME - A 3rd Generation Synchrotron Light Source for the Middle East
Ulkue, Dincer; Rahighi, Javad; Winick, Herman
2007-01-19
SESAME (Synchrotron-light for Experimental Science and Applications in the Middle East) will be the Middle East's first international research center. It is a cooperative venture by the scientists and governments of the region with founding members Bahrain, Egypt, Israel, Jordan, Pakistan, Palestine Authority, and Turkey. Iran is in the process of finalizing its formal membership. Other countries (Cyprus, Morocco, and the United Arab Emirates) are also expected to join. The permanent Council of member states has full responsibility for the project. Members provide the annual operating budget. Observer countries are Germany, Greece, Italy, Kuwait, Portugal, Russian Federation, Sweden, the UK, and the US. SESAME is being developed under the umbrella of UNESCO. Jordan was selected as the building site. SESAME will offer excellent opportunities for training of Middle East scientists and attract those working abroad to consider returning. SESAME will be a 2.5GeV 3rd Generation light source (emittance 26nm-rad, circumference {approx}133m), providing excellent performance for structural molecular biology, molecular environmental science, surface and interface science, microelectromechanical devices, x-ray imaging, archaeological microanalysis, and materials characterization. It will cover a broad spectral range from the infrared to hard x-rays and will have 12 straight sections for insertion devices (average length 2.75m). The injector will be the BESSY I 0.8 GeV booster synchrotron which has been given as a gift from Germany. Four committees advise the Council and assist in developing the technical design, beam lines, user community, and scientific Program. The SESAME building, now in construction with funds and a site provided by Jordan, is scheduled for completion in late 2006 after which the BESSY I injector will be installed. First stored beam in the new 2.5 GeV ring is planned for 2009 with six initial beamlines planned. Some beamlines will be built by member
Building monument materials during the 3rd-4rd millennium (Portugal)
NASA Astrophysics Data System (ADS)
Moita, Patricia; Pedro, Jorge; Boaventura, Rui; Mataloto, Rui; Maximo, Jaime; Almeida, Luís; Nogueira, Pedro
2014-05-01
Dolmens are the most conspicuous remains of the populations of the 4th and first half of 3rd millennia BCE. These tombs are impressive not only for their monumentality, but also because of the socioeconomic investment they represent for those Neolithic communities, namely from the Central-South of Portugal, who built them. Although dolmens have been studied for their funerary content and typologies, an interdisciplinary approach toward the geological characterization and sourcing of stones used in these constructions has not received enough attention from researchers. With MEGAGEO project a multidisciplinary group of geologist and archaeologists intends to assess the relationship between the distribution of dolmens in Central-South Portugal, their source materials, and the geological landscape. GIS will map the information gathered and will be used to analyse these relationships. The selection of the areas, with distinctive geologies (limestone vs granite), will allow to verify if human patterns of behaviour regarding the selection of megaliths are similar or different regionally. Geologically the first target area (Freixo, Alentejo) is dominated by a small intrusion of gabbro mingled/mixed within a granodioritic intrusion both related with variscan orogeny. Granodiorite exhibit several enclaves of igneous and metamorphic nature attesting the interaction between both igneous rocks as well with enclosing gneisses. Despite Alentejo region have a reduced number of outcrops the granodiorite provides rounded to tabular metric blocks. The gabbro is very coarse grained, sometimes with a cumulate texture, and their fracturing and weathering provide very fresh tabular blocks. The five studied dolmens (Quinta do Freixo #1 to #5) are implanted in a large granodioritic intrusion, around the gabbroic rocks, within an area of approximately 9km2. The medium grained granodiorite is ubiquity in all the dolmens slabs and occasionally it can be observed features of mixing and
2013-01-01
Introduction In the thorax there are normally 11 pairs of intercostal spaces: the spaces between adjacent ribs. The intercostal spaces contain intercostal muscles, intercostal nerves and vessels. Case presentation During a routine dissection for undergraduate medical students, we observed a variation involving the left 3rd rib and 3rd costal cartilage in the cadaver of a man of Indian ethnicity aged about 65 years. The left 3rd rib and its costal cartilage were bifurcated at their costochondral junction enclosing a small circular additional intercostal space. Muscle tissue covered by deep fascia was present in this circular intercostal space. The muscle in the circular intercostal space received its nerve supply from a branch of the 2nd intercostal nerve. Conclusions Knowledge of such variations is helpful to surgeons operating on the anterior thoracic wall involving ribs and intercostal spaces. Knowing the possibility of the presence of an additional space between normal intercostal spaces can guide a surgeon through to a successful surgery. PMID:23298541
Robinson, P P; Loescher, A R; Smith, K G
1999-05-01
We have previously shown that avoidance of lingual flap retraction with a Howarth periosteal elevator during lower 3rd molar removal, reduces the incidence of lingual nerve damage. In that study, the surgery was undertaken by qualified staff and we have now assessed the effect of revising the method taught to our junior undergraduate dental students. We evaluated the outcome of surgery undertaken by 2 consecutive years of students, each group being taught 1 of the 2 methods. A total of 200 patients requiring lower 3rd molar removal under local anaesthesia were included in the study. In year 1, the surgery included elevation of a lingual flap and insertion of a Howarth elevator adjacent to the lingual plate; in year 2 this part of the procedure was avoided by using a purely buccal approach. There were no significant differences between the levels of tooth eruption and types of impaction of the teeth removed in each year. Lingual sensory disturbance occurred in 3 patients in the 'flap' group (3.3%) and in 1 patient (0.9%) in the 'no flap' group. As this incidence is not significantly different in the 2 groups (P < 0.4), we conclude that avoidance of lingual retraction by students undertaking lower 3rd molar removal does not appear to place the lingual nerve at greater risk. In view of the results of our previous study, we therefore advocate this method for use in undergraduate dental education. PMID:10530161
Does 3rd Age + 3rd World = 3rd Class?
ERIC Educational Resources Information Center
Tout, Ken
1992-01-01
Demographic changes, migration, and industrialization are having drastic effects on older adults in developing nations. Local programs such as Pro Vida in Colombia, supported by Help Age International, rely on the support of volunteers to improve the quality of life for elderly people. (SK)
[Study of analysis of the singularity of R-wave by using wavelet transform].
Wang, Weidong; Wang, Buqing; Liu, Guangrong
2011-08-01
Singularity is a basic feature of biological signals. Based on the variations of wavelet transform modulus maxima in multi-scales, we studied the basic theorem for analyzing the singularity and proposed an algorithm for calculating lipschitz exponent. Then we applied the algorithm to calculate the singularity of R-wave in ECG. Our study found that the level of singularity of R-waves in ECG between the 10 arrhythm patients randomly chosen and the healthy persons was significantly different, with the level of singularity of R-wave of normal persons remarkably higher than that of arrhythmia patients.
PREFACE: 3rd International Workshop on Materials Analysis and Processing in Magnetic Fields (MAP3)
NASA Astrophysics Data System (ADS)
Sakka, Yoshio; Hirota, Noriyuki; Horii, Shigeru; Ando, Tsutomu
2009-07-01
The 3rd International Workshop on Materials Analysis and Processing in Materials Fields (MAP3) was held on 14-16 May 2008 at the University of Tokyo, Japan. The first was held in March 2004 at the National High Magnetic Field Laboratory in Tallahassee, USA. Two years later the second took place in Grenoble, France. MAP3 was held at The University of Tokyo International Symposium, and jointly with MANA Workshop on Materials Processing by External Stimulation, and JSPS CORE Program of Construction of the World Center on Electromagnetic Processing of Materials. At the end of MAP3 it was decided that the next MAP4 will be held in Atlanta, USA in 2010. Processing in magnetic fields is a rapidly expanding research area with a wide range of promising applications in materials science. MAP3 focused on the magnetic field interactions involved in the study and processing of materials in all disciplines ranging from physics to chemistry and biology: Magnetic field effects on chemical, physical, and biological phenomena Magnetic field effects on electrochemical phenomena Magnetic field effects on thermodynamic phenomena Magnetic field effects on hydrodynamic phenomena Magnetic field effects on crystal growth Magnetic processing of materials Diamagnetic levitation Magneto-Archimedes effect Spin chemistry Application of magnetic fields to analytical chemistry Magnetic orientation Control of structure by magnetic fields Magnetic separation and purification Magnetic field-induced phase transitions Materials properties in high magnetic fields Development of NMR and MRI Medical application of magnetic fields Novel magnetic phenomena Physical property measurement by Magnetic fields High magnetic field generation> MAP3 consisted of 84 presentations including 16 invited talks. This volume of Journal of Physics: Conference Series contains the proceeding of MAP3 with 34 papers that provide a scientific record of the topics covered by the conference with the special topics (13 papers) in
FOREWORD: 3rd International Workshop on New Computational Methods for Inverse Problems (NCMIP 2013)
NASA Astrophysics Data System (ADS)
Blanc-Féraud, Laure; Joubert, Pierre-Yves
2013-10-01
Conference logo This volume of Journal of Physics: Conference Series is dedicated to the scientific contributions presented during the 3rd International Workshop on New Computational Methods for Inverse Problems, NCMIP 2013 (http://www.farman.ens-cachan.fr/NCMIP_2013.html). This workshop took place at Ecole Normale Supérieure de Cachan, in Cachan, France, on 22 May 2013, at the initiative of Institut Farman. The prior editions of NCMIP also took place in Cachan, France, firstly within the scope of the ValueTools Conference, in May 2011 (http://www.ncmip.org/2011/), and secondly at the initiative of Institut Farman, in May 2012 (http://www.farman.ens-cachan.fr/NCMIP_2012.html). The NCMIP Workshop focused on recent advances in the resolution of inverse problems. Indeed inverse problems appear in numerous scientific areas such as geophysics, biological and medical imaging, material and structure characterization, electrical, mechanical and civil engineering, and finances. The resolution of inverse problems consists of estimating the parameters of the observed system or structure from data collected by an instrumental sensing or imaging device. Its success firstly requires the collection of relevant observation data. It also requires accurate models describing the physical interactions between the instrumental device and the observed system, as well as the intrinsic properties of the solution itself. Finally, it requires the design of robust, accurate and efficient inversion algorithms. Advanced sensor arrays and imaging devices provide high rate and high volume data; in this context, the efficient resolution of the inverse problem requires the joint development of new models and inversion methods, taking computational and implementation aspects into account. During this one-day workshop, researchers had the opportunity to bring to light and share new techniques and results in the field of inverse problems. The topics of the workshop were: algorithms and computational
PREFACE: 3rd Workshop on Theory, Modelling and Computational Methods for Semiconductors (TMCSIII)
NASA Astrophysics Data System (ADS)
Califano, Marco; Migliorato, Max; Probert, Matt
2012-05-01
These conference proceedings contain the written papers of the contributions presented at the 3rd International Conference on Theory, Modelling and Computational Methods for Semiconductor materials and nanostructures. The conference was held at the School of Electronic and Electrical Engineering, University of Leeds, Leeds, UK on 18-20 January 2012. The previous conferences in this series took place in 2010 at St William's College, York and in 2008 at the University of Manchester, UK. The development of high-speed computer architectures is finally allowing the routine use of accurate methods for calculating the structural, thermodynamic, vibrational, optical and electronic properties of semiconductors and their hetero- and nano-structures. The scope of this conference embraces modelling, theory and the use of sophisticated computational tools in semiconductor science and technology, where there is substantial potential for time-saving in R&D. Theoretical approaches represented in this meeting included: Density Functional Theory, Tight Binding, Semiempirical Pseudopotential Methods, Effective Mass Models, Empirical Potential Methods and Multiscale Approaches. Topics included, but were not limited to: Optical and Transport Properties of Quantum Nanostructures including Colloids and Nanotubes, Plasmonics, Magnetic Semiconductors, Graphene, Lasers, Photonic Structures, Photovoltaic and Electronic Devices. This workshop ran for three days, with the objective of bringing together UK and international leading experts in the theoretical modelling of Group IV, III-V and II-VI semiconductors, as well as students, postdocs and early-career researchers. The first day focused on providing an introduction and overview of this vast field, aimed particularly at students, with several lectures given by recognised experts in various theoretical approaches. The following two days showcased some of the best theoretical research carried out in the UK in this field, with several
Gil, José J; Ossikovski, Razvigor; José, Ignacio San
2016-04-01
Singular Mueller matrices play an important role in polarization algebra and have peculiar properties that stem from the fact that either the medium exhibits maximum diattenuation and/or polarizance or because its associated canonical depolarizer has the property of fully randomizing the circular component (at least) of the states of polarization of light incident on it. The formal reasons for which the Mueller matrix M of a given medium is singular are systematically investigated, analyzed, and interpreted in the framework of the serial decompositions and the characteristic ellipsoids of M. The analysis allows for a general classification and geometric representation of singular Mueller matrices, which are of potential usefulness to experimentalists dealing with such media. PMID:27140769
Gil, José J; Ossikovski, Razvigor; José, Ignacio San
2016-04-01
Singular Mueller matrices play an important role in polarization algebra and have peculiar properties that stem from the fact that either the medium exhibits maximum diattenuation and/or polarizance or because its associated canonical depolarizer has the property of fully randomizing the circular component (at least) of the states of polarization of light incident on it. The formal reasons for which the Mueller matrix M of a given medium is singular are systematically investigated, analyzed, and interpreted in the framework of the serial decompositions and the characteristic ellipsoids of M. The analysis allows for a general classification and geometric representation of singular Mueller matrices, which are of potential usefulness to experimentalists dealing with such media.
Identifying conical singularities
Oliveira-Neto, G. |
1996-09-01
A method based upon the concept of holonomy of a metric space{endash}time ({ital M},{ital g}), in order to identify the presence of conical singularities in {ital M} is proposed. The validity and usefulness of this so-called holonomy method is proven by applying it to a set of four-dimensional space{endash}times and one three-dimensional space{endash}time. The holonomy method predictions are confirmed by the comparison with the predictions obtained after coordinate transformations which take the metrics {ital g}, to a new basis where the global properties of conical singularities are explicitly seen. {copyright} {ital 1996 American Institute of Physics.}
Funder, D C
2001-01-01
Personality psychology is as active today as at any point in its history. The classic psychoanalytic and trait paradigms are active areas of research, the behaviorist paradigm has evolved into a new social-cognitive paradigm, and the humanistic paradigm is a basis of current work on cross-cultural psychology. Biology and evolutionary theory have also attained the status of new paradigms for personality. Three challenges for the next generation of research are to integrate these disparate approaches to personality (particularly the trait and social-cognitive paradigms), to remedy the imbalance in the person-situation-behavior triad by conceptualizing the basic properties of situations and behaviors, and to add to personality psychology's thin inventory of basic facts concerning the relations between personality and behavior.
ERIC Educational Resources Information Center
Bates, Richard D.
This lecture recounts personal experiences and discusses environmental issues that invoked a desire to teach about the things threatening the earth. Human population growth is cited as the first and foremost environmental challenge in the 20th century. A J-shaped curve is used to illustrate an increase in human population. The relationship between…
FOREWORD: 3rd International Workshop on New Computational Methods for Inverse Problems (NCMIP 2013)
NASA Astrophysics Data System (ADS)
Blanc-Féraud, Laure; Joubert, Pierre-Yves
2013-10-01
Conference logo This volume of Journal of Physics: Conference Series is dedicated to the scientific contributions presented during the 3rd International Workshop on New Computational Methods for Inverse Problems, NCMIP 2013 (http://www.farman.ens-cachan.fr/NCMIP_2013.html). This workshop took place at Ecole Normale Supérieure de Cachan, in Cachan, France, on 22 May 2013, at the initiative of Institut Farman. The prior editions of NCMIP also took place in Cachan, France, firstly within the scope of the ValueTools Conference, in May 2011 (http://www.ncmip.org/2011/), and secondly at the initiative of Institut Farman, in May 2012 (http://www.farman.ens-cachan.fr/NCMIP_2012.html). The NCMIP Workshop focused on recent advances in the resolution of inverse problems. Indeed inverse problems appear in numerous scientific areas such as geophysics, biological and medical imaging, material and structure characterization, electrical, mechanical and civil engineering, and finances. The resolution of inverse problems consists of estimating the parameters of the observed system or structure from data collected by an instrumental sensing or imaging device. Its success firstly requires the collection of relevant observation data. It also requires accurate models describing the physical interactions between the instrumental device and the observed system, as well as the intrinsic properties of the solution itself. Finally, it requires the design of robust, accurate and efficient inversion algorithms. Advanced sensor arrays and imaging devices provide high rate and high volume data; in this context, the efficient resolution of the inverse problem requires the joint development of new models and inversion methods, taking computational and implementation aspects into account. During this one-day workshop, researchers had the opportunity to bring to light and share new techniques and results in the field of inverse problems. The topics of the workshop were: algorithms and computational
Singular Vectors' Subtle Secrets
ERIC Educational Resources Information Center
James, David; Lachance, Michael; Remski, Joan
2011-01-01
Social scientists use adjacency tables to discover influence networks within and among groups. Building on work by Moler and Morrison, we use ordered pairs from the components of the first and second singular vectors of adjacency matrices as tools to distinguish these groups and to identify particularly strong or weak individuals.
ERIC Educational Resources Information Center
Shore, Rebecca Martin
1996-01-01
Describes how a typical high school in Huntington Beach, California, curbed disruptive student behavior by personalizing the school experience for "problem" students. Through mostly volunteer efforts, an adopt-a-kid program was initiated that matched kids' learning styles to adults' personality styles and resulted in fewer suspensions and numerous…
Tunnelling of the 3rd kind: A test of the effective non-locality of quantum field theory
NASA Astrophysics Data System (ADS)
Gardiner, Simon A.; Gies, Holger; Jaeckel, Joerg; Wallace, Chris J.
2013-03-01
Integrating out virtual quantum fluctuations in an originally local quantum field theory results in an effective theory which is non-local. In this letter we argue that tunnelling of the 3rd kind —where particles traverse a barrier by splitting into a pair of virtual particles which recombine only after a finite distance— provides a direct test of this non-locality. We sketch a quantum-optical setup to test this effect, and investigate observable effects in a simple toy model.
He, Zhijian; Schulz, Anita; Wan, Xiaomeng; Seitz, Joshua; Bludau, Herdis; Alakhova, Daria Y; Darr, David B; Perou, Charles M; Jordan, Rainer; Ojima, Iwao; Kabanov, Alexander V; Luxenhofer, Robert
2015-06-28
The clinically and commercially successful taxanes, paclitaxel and docetaxel suffer from two major drawbacks, namely their very low aqueous solubility and the risk of developing resistance. Here, we present a method that overcomes both drawbacks in a very simple manner. We formulated 3rd generation taxoids, able to avoid common drug resistance mechanisms with doubly amphiphilic poly(2-oxazoline)s (POx), a safe and highly efficient polymer for the formulation of extremely hydrophobic drugs. We found excellent solubilization of different 3rd generation taxoids irrespective of the drug's chemical structures with essentially quantitative drug loading and final drug to polymer ratios around unity. The small, highly loaded micelles with a hydrodynamic diameter of less than 100nm are excellently suited for parenteral administration. Moreover, a selected formulation with the taxoid SB-T-1214 is about one to two orders of magnitude more active in vitro than paclitaxel in the multidrug resistant breast cancer cell line LCC6-MDR. In contrast, in wild-type LCC6, no difference was observed. Using a q4d×4 dosing regimen, we also found that POx/SB-T-1214 significantly inhibits the growth of LCC6-MDR orthotropic tumors, outperforming commercial paclitaxel drug Taxol and Cremophor EL formulated SB-T-1214.
Singularities in loop quantum cosmology.
Cailleteau, Thomas; Cardoso, Antonio; Vandersloot, Kevin; Wands, David
2008-12-19
We show that simple scalar field models can give rise to curvature singularities in the effective Friedmann dynamics of loop quantum cosmology (LQC). We find singular solutions for spatially flat Friedmann-Robertson-Walker cosmologies with a canonical scalar field and a negative exponential potential, or with a phantom scalar field and a positive potential. While LQC avoids big bang or big rip type singularities, we find sudden singularities where the Hubble rate is bounded, but the Ricci curvature scalar diverges. We conclude that the effective equations of LQC are not in themselves sufficient to avoid the occurrence of curvature singularities.
Neural Excitability and Singular Bifurcations.
De Maesschalck, Peter; Wechselberger, Martin
2015-12-01
We discuss the notion of excitability in 2D slow/fast neural models from a geometric singular perturbation theory point of view. We focus on the inherent singular nature of slow/fast neural models and define excitability via singular bifurcations. In particular, we show that type I excitability is associated with a novel singular Bogdanov-Takens/SNIC bifurcation while type II excitability is associated with a singular Andronov-Hopf bifurcation. In both cases, canards play an important role in the understanding of the unfolding of these singular bifurcation structures. We also explain the transition between the two excitability types and highlight all bifurcations involved, thus providing a complete analysis of excitability based on geometric singular perturbation theory.
NASA Astrophysics Data System (ADS)
Siebert, L.; Simkin, T.; Kimberly, P.
2010-12-01
The 3rd edition of the Smithsonian Institution’s Volcanoes of the World incorporates data on the world’s volcanoes and their eruptions compiled since 1968 by the Institution’s Global Volcanism Program (GVP). Published this Fall jointly by the Smithsonian and the University of California Press, it supplements data from the 1994 2nd edition and includes new data on the number of people living in proximity to volcanoes, the dominant rock lithologies at each volcano, Holocene caldera-forming eruptions, and preliminary lists of Pleistocene volcanoes and large-volume Pleistocene eruptions. The 3rd edition contains data on nearly 1550 volcanoes of known or possible Holocene age, including chronologies, characteristics, and magnitudes for >10,400 Holocene eruptions. The standard 20 eruptive characteristics of the IAVCEI volcano catalog series have been modified to include dated vertical edifice collapse events due to magma chamber evacuation following large-volume explosive eruptions or mafic lava effusion, and lateral sector collapse. Data from previous editions of Volcanoes of the World are also supplemented by listings of up to the 5 most dominant lithologies at each volcano, along with data on population living within 5, 10, 30, and 100 km radii of each volcano or volcanic field. Population data indicate that the most populated regions also contain the most frequently active volcanoes. Eruption data document lava and tephra volumes and Volcanic Explosivity Index (VEI) assignments for >7800 eruptions. Interpretation of VRF data has led to documentation of global eruption rates and the power law relationship between magnitude and frequency of volcanic eruptions. Data with volcanic hazards implications include those on fatalities and evacuations and the rate at which eruptions reach their climax. In recognition of the hazards implications of potential resumption of activity at pre-Holocene volcanoes, the 3rd edition includes very preliminary lists of Pleistocene
3rd Tech DeltaSphere-3000 Laser 3D Scene Digitizer infrared laser scanner hazard analysis.
Augustoni, Arnold L.
2005-02-01
A laser hazard analysis and safety assessment was performed for the 3rd Tech model DeltaSphere-3000{reg_sign} Laser 3D Scene Digitizer, infrared laser scanner model based on the 2000 version of the American National Standard Institute's Standard Z136.1, for the Safe Use of Lasers. The portable scanner system is used in the Robotic Manufacturing Science and Engineering Laboratory (RMSEL). This scanning system had been proposed to be a demonstrator for a new application. The manufacture lists the Nominal Ocular Hazard Distance (NOHD) as less than 2 meters. It was necessary that SNL validate this NOHD prior to its use as a demonstrator involving the general public. A formal laser hazard analysis is presented for the typical mode of operation for the current configuration as well as a possible modified mode and alternative configuration.
Abbs, Brandon; Achalia, Rashmin M; Adelufosi, Adegoke O; Aktener, Ahmet Yiğit; Beveridge, Natalie J; Bhakta, Savita G; Blackman, Rachael K; Bora, Emre; Byun, MS; Cabanis, Maurice; Carrion, Ricardo; Castellani, Christina A; Chow, Tze Jen; Dmitrzak-Weglarz, M; Gayer-Anderson, Charlotte; Gomes, Felipe V; Haut, Kristen; Hori, Hiroaki; Kantrowitz, Joshua T; Kishimoto, Taishiro; Lee, Frankie HF; Lin, Ashleigh; Palaniyappan, Lena; Quan, Meina; Rubio, Maria D; Ruiz de Azúa, Sonia; Sahoo, Saddichha; Strauss, Gregory P; Szczepankiewicz, Aleksandra; Thompson, Andrew D; Trotta, Antonella; Tully, Laura M; Uchida, Hiroyuki; Velthorst, Eva; Young, Jared W; O’Shea, Anne; DeLisi, Lynn E.
2013-01-01
The 3rd Schizophrenia International Research Society Conference was held in Florence, Italy, April 14-18, 2012.and this year had as its emphasis, “The Globalization of Research”. Student travel awardees served as rapporteurs for each oral session and focused their summaries on the most significant findings that emerged and the discussions that followed. The following report is a composite of these summaries. We hope that it will provide an overview for those who were present, but could not participate in all sessions, and those who did not have the opportunity to attend, but who would be interested in an update on current investigations ongoing in the field of schizophrenia research. PMID:22910407
Albin, D. S.; del Cueto, J. A.; Demtsu, S. H.; Bansal, S.
2011-03-01
The correlation of stress-induced changes in the performance of laboratory-made CdTe solar cells with various 2nd and 3rd level metrics is discussed. The overall behavior of aggregated data showing how cell efficiency changes as a function of open-circuit voltage (Voc), short-circuit current density (Jsc), and fill factor (FF) is explained using a two-diode, PSpice model in which degradation is simulated by systematically changing model parameters. FF shows the highest correlation with performance during stress, and is subsequently shown to be most affected by shunt resistance, recombination and in some cases voltage-dependent collection. Large decreases in Jsc as well as increasing rates of Voc degradation are related to voltage-dependent collection effects and catastrophic shunting respectively. Large decreases in Voc in the absence of catastrophic shunting are attributed to increased recombination. The relevance of capacitance-derived data correlated with both Voc and FF is discussed.
Hayes, Rashelle B.; Geller, Alan C.; Crawford, Sybil L.; Jolicoeur, Denise; Churchill, Linda C.; Okuyemi, Kola; David, Sean P.; Adams, Michael; Waugh, Jonathan; Allen, Sharon S.; Leone, Frank T.; Fauver, Randy; Leung, Katherine; Liu, Qin; Ockene, Judith K.
2015-01-01
Objective Physicians play a critical role in addressing tobacco dependence, yet report limited training. Tobacco dependence treatment curricula for medical students could improve performance in this area. This study identified student and medical school tobacco treatment curricula characteristics associated with intentions and use of the 5As for tobacco treatment among 3rd year U.S. medical students. Methods Third year medical students (N=1065, 49.3% male) from 10 U.S. medical schools completed a survey in 2009-2010 assessing student characteristics, including demographics, tobacco treatment knowledge, and self-efficacy. Tobacco curricula characteristics assessed included amount and type of classroom instruction, frequency of tobacco treatment observation, instruction, and perception of preceptors as role models. Results Greater tobacco treatment knowledge, self-efficacy, and curriculum-specific variables were associated with 5A intentions, while younger age, tobacco treatment self-efficacy, intentions, and each curriculum-specific variable was associated with greater 5A behaviors. When controlling for important student variables, greater frequency of receiving 5A instruction (OR = 1.07; 95%CI 1.01-1.12) and perception of preceptors as excellent role models in tobacco treatment (OR = 1.35; 95%CI 1.04-1.75) were significant curriculum predictors of 5A intentions. Greater 5A instruction (B = .06 (.03); p< .05) and observation of tobacco treatment (B= .35 (.02); p< .001) were significant curriculum predictors of greater 5A behaviors. Conclusions Greater exposure to tobacco treatment teaching during medical school is associated with both greater intentions to use and practice tobacco 5As. Clerkship preceptors, or those physicians who provide training to medical students, may be particularly influential when they personally model and instruct students in tobacco dependence treatment. PMID:25572623
Taking Perspective: Personal Pronouns Affect Experiential Aspects of Literary Reading.
Hartung, Franziska; Burke, Michael; Hagoort, Peter; Willems, Roel M
2016-01-01
Personal pronouns have been shown to influence cognitive perspective taking during comprehension. Studies using single sentences found that 3rd person pronouns facilitate the construction of a mental model from an observer's perspective, whereas 2nd person pronouns support an actor's perspective. The direction of the effect for 1st person pronouns seems to depend on the situational context. In the present study, we investigated how personal pronouns influence discourse comprehension when people read fiction stories and if this has consequences for affective components like emotion during reading or appreciation of the story. We wanted to find out if personal pronouns affect immersion and arousal, as well as appreciation of fiction. In a natural reading paradigm, we measured electrodermal activity and story immersion, while participants read literary stories with 1st and 3rd person pronouns referring to the protagonist. In addition, participants rated and ranked the stories for appreciation. Our results show that stories with 1st person pronouns lead to higher immersion. Two factors-transportation into the story world and mental imagery during reading-in particular showed higher scores for 1st person as compared to 3rd person pronoun stories. In contrast, arousal as measured by electrodermal activity seemed tentatively higher for 3rd person pronoun stories. The two measures of appreciation were not affected by the pronoun manipulation. Our findings underscore the importance of perspective for language processing, and additionally show which aspects of the narrative experience are influenced by a change in perspective. PMID:27192060
Taking Perspective: Personal Pronouns Affect Experiential Aspects of Literary Reading
Burke, Michael; Hagoort, Peter; Willems, Roel M.
2016-01-01
Personal pronouns have been shown to influence cognitive perspective taking during comprehension. Studies using single sentences found that 3rd person pronouns facilitate the construction of a mental model from an observer’s perspective, whereas 2nd person pronouns support an actor’s perspective. The direction of the effect for 1st person pronouns seems to depend on the situational context. In the present study, we investigated how personal pronouns influence discourse comprehension when people read fiction stories and if this has consequences for affective components like emotion during reading or appreciation of the story. We wanted to find out if personal pronouns affect immersion and arousal, as well as appreciation of fiction. In a natural reading paradigm, we measured electrodermal activity and story immersion, while participants read literary stories with 1st and 3rd person pronouns referring to the protagonist. In addition, participants rated and ranked the stories for appreciation. Our results show that stories with 1st person pronouns lead to higher immersion. Two factors—transportation into the story world and mental imagery during reading—in particular showed higher scores for 1st person as compared to 3rd person pronoun stories. In contrast, arousal as measured by electrodermal activity seemed tentatively higher for 3rd person pronoun stories. The two measures of appreciation were not affected by the pronoun manipulation. Our findings underscore the importance of perspective for language processing, and additionally show which aspects of the narrative experience are influenced by a change in perspective. PMID:27192060
Organizational Support for the 3rd Summer Institute on Complex Plasmas, July 30 – August 8, 2012
Lopez, Jose L.
2012-07-01
This grant provided partial funds for American graduate students to attend the 3rd Graduate Summer Institute on Complex Plasmas, which was held from July 30 to August 8, 2012 at Seton Hall University in South Orange, New Jersey. The Graduate Summer Institute is a topical series of instructional workshops held bi-annually on the emerging field of complex plasmas that is jointly organized through a collaboration between American and German-European Union plasmas researchers. This specialized program brings together many of the world's leading researchers in the specialized area of complex plasmas, who freely provide instructional lectures and tutorials on the most recent research and discoveries done in this branch of plasma science. The partial funds provided by this grant helped support the travel and accommodation expenses of the participating American students and tutorial instructors. Partial funds further supported the travel and accommodation of three renown American plasma researchers that provided educational tutorials to the thirty-eight participating students from the United States, Europe, and Asia. The organized program afforded a unique opportunity for the participating American graduate students to learn about and engage more deeply in an area of plasma science that is not studied in any of the graduate educational curriculums provided by universities in the United States of America. The educational experience offered by this program provided the necessary knowledge needed by future American plasma researchers to keep the national plasma research effort on the cutting-edge and keep the national plasma community as a global leader.
Chubar O.; Berman, L; Chu, Y.S.; Fluerasu, A.; Hulbert, S.; Idir, M.; Kaznatcheev, K.; Shapiro, D.; Baltser, J.
2012-04-04
Partially-coherent wavefront propagation calculations have proven to be feasible and very beneficial in the design of beamlines for 3rd and 4th generation Synchrotron Radiation (SR) sources. These types of calculations use the framework of classical electrodynamics for the description, on the same accuracy level, of the emission by relativistic electrons moving in magnetic fields of accelerators, and the propagation of the emitted radiation wavefronts through beamline optical elements. This enables accurate prediction of performance characteristics for beamlines exploiting high SR brightness and/or high spectral flux. Detailed analysis of radiation degree of coherence, offered by the partially-coherent wavefront propagation method, is of paramount importance for modern storage-ring based SR sources, which, thanks to extremely small sub-nanometer-level electron beam emittances, produce substantial portions of coherent flux in X-ray spectral range. We describe the general approach to partially-coherent SR wavefront propagation simulations and present examples of such simulations performed using 'Synchrotron Radiation Workshop' (SRW) code for the parameters of hard X-ray undulator based beamlines at the National Synchrotron Light Source II (NSLS-II), Brookhaven National Laboratory. These examples illustrate general characteristics of partially-coherent undulator radiation beams in low-emittance SR sources, and demonstrate advantages of applying high-accuracy physical-optics simulations to the optimization and performance prediction of X-ray optical beamlines in these new sources.
The 3rd Canadian Symposium on Hepatitis C Virus: Expanding care in the interferon-free era
MacParland, Sonya A; Bilodeau, Marc; Grebely, Jason; Bruneau, Julie; Cooper, Curtis; Klein, Marina; Sagan, Selena M; Choucha, Norma; Balfour, Louise; Bialystok, Frank; Krajden, Mel; Raven, Jennifer; Roberts, Eve; Russell, Rodney; Houghton, Michael; Tyrrell, D Lorne; Feld, Jordan J
2014-01-01
Hepatitis C virus (HCV) currently infects approximately 250,000 individuals in Canada and causes more years of life lost than any other infectious disease in the country. In August 2011, new therapies were approved by Health Canada that have achieved higher response rates among those treated, but are poorly tolerated. By 2014/2015, short-course, well-tolerated treatments with cure rates >95% will be available. However, treatment uptake is poor due to structural, financial, geographical, cultural and social barriers. As such, ‘Barriers to access to HCV care in Canada’ is a crucial topic that must be addressed to decrease HCV disease burden and potentially eliminate HCV in Canada. Understanding how to better care for HCV-infected individuals requires integration across multiple disciplines including researchers, clinical services and policy makers to address the major populations affected by HCV including people who inject drugs, baby boomers, immigrants and Aboriginal and/or First Nations people. In 2012, the National CIHR Research Training Program in Hepatitis C organized the 1st Canadian Symposium on Hepatitis C Virus (CSHCV) in Montreal, Quebec. The 2nd CSHCV was held in 2013 in Victoria, British Columbia. Both symposia were highly successful, attracting leading international faculty with excellent attendance leading to dialogue and knowledge translation among attendees of diverse backgrounds. The current article summarizes the 3rd CSHCV, held February 2014, in Toronto, Ontario. PMID:25314353
Gregory, Louis
2014-09-20
This report satisfies the U.S. Department of Energy (DOE), National Nuclear Security Administration Nevada Field Office (NNSA/NFO) commitment to prepare a quarterly summary report of radioactive waste shipments to the Nevada National Security Site (NNSS) Radioactive Waste Management Complex (RWMC) at Area 5. There were no shipments sent for offsite treatment and returned to the NNSS this quarter. This report summarizes the 3rd quarter of Fiscal Year (FY) 2014 low-level radioactive waste (LLW) and mixed low-level radioactive waste (MLLW) shipments. This report also includes annual summaries for FY 2014 in Tables 4 and 5. Tabular summaries are provided which include the following: Sources of and carriers for LLW and MLLW shipments to and from the NNSS; Number and external volume of LLW and MLLW shipments; Highway routes used by carriers; and Incident/accident data applicable to LLW and MLLW shipments. In this report shipments are accounted for upon arrival at the NNSS, while disposal volumes are accounted for upon waste burial. The disposal volumes presented in this report do not include minor volumes of non-radioactive materials that were approved for disposal. Volume reports showing cubic feet generated using the Low-Level Waste Information System may vary slightly due to differing rounding conventions.
Evaluation of a model of dissertation supervision for 3rd year B.Sc. undergraduate nursing students.
Scholefield, Donna; Cox, Georgina
2016-03-01
All English universities now offer an all degree undergraduate nursing programme. Many currently use an individual supervision model to support final year dissertation students, but with increased numbers and limited resources new models of supervision are needed. This study evaluated a mixed (group and individual) model of dissertation supervision to determine its effectiveness for a large group of undergraduate nursing students. A sample of 3rd year students and their supervisors were selected from one large university. An evaluation survey was conducted using anonymous internet-based questionnaires and focus groups. The data was analysed using Survey Monkey, SPSS and thematic analysis. A 51% (n = 56/110) response rate (students) and 65% (n = 24/37) for supervisors was obtained. The majority of students and supervisors were satisfied with the new model. There was a mixed response to the group workshops and supervision groups. Three themes emerged from the qualitative data: engaging with the process, motivation to supervise and valuing the process. The supervision process is a struggle but both parties gained considerably from going through the process. In conclusion, a mixed model of supervision together with a range of other learning resources can be an effective approach in supporting students through the dissertation process. PMID:26700648
Evaluation of a model of dissertation supervision for 3rd year B.Sc. undergraduate nursing students.
Scholefield, Donna; Cox, Georgina
2016-03-01
All English universities now offer an all degree undergraduate nursing programme. Many currently use an individual supervision model to support final year dissertation students, but with increased numbers and limited resources new models of supervision are needed. This study evaluated a mixed (group and individual) model of dissertation supervision to determine its effectiveness for a large group of undergraduate nursing students. A sample of 3rd year students and their supervisors were selected from one large university. An evaluation survey was conducted using anonymous internet-based questionnaires and focus groups. The data was analysed using Survey Monkey, SPSS and thematic analysis. A 51% (n = 56/110) response rate (students) and 65% (n = 24/37) for supervisors was obtained. The majority of students and supervisors were satisfied with the new model. There was a mixed response to the group workshops and supervision groups. Three themes emerged from the qualitative data: engaging with the process, motivation to supervise and valuing the process. The supervision process is a struggle but both parties gained considerably from going through the process. In conclusion, a mixed model of supervision together with a range of other learning resources can be an effective approach in supporting students through the dissertation process.
Su, Yu-Huei; Luh, Jer-Junn; Chen, Hsin-I; Lin, Chao-Chen; Liao, Miin-Jiun; Chen, Heng-Shuen
2010-06-01
The current study examined the effects of applying relaxation breathing training (RBT) as a means to reduce music performance anxiety (MPA) in young, talented musicians. A group of 59 young musicians from 3rd to 6th grade participated in this study, and all of them started RBT twice a week for 2 months prior to the examination. Four tests--2 mos, 1 mos, half an hour and 5 min before the examination--were conducted to examine the level of MPA after the application of RBT. Results show that the degree of MPA 5 min before the trial was lower than the degree of performance anxiety half an hour before the jury (t = -3.683, p < 0.01), which indicated that the RBT was associated with a decrease in MPA. Although a series of RBT exercises was applied, results indicated that when approaching the date of examination, the degree of performance anxiety still increased and reached its maximum half an hour before the jury. The recommendation for future studies is to combine the application of RBT with other methods to expand its effect in reducing MPA.
Ando, Noriyasu; Kanzaki, Ryohei
2004-02-01
The 3rd axillary muscles (3AXMs) in the mesothorax in hawkmoths are direct flight muscles and pull forewings back along to the body axis. The 3AXMs are regarded as steering muscles because of their changeable activities during turning flight under tethered conditions. We investigated activities of the upper unit of the 3AXMs during free flight with a micro-telemetry device and captured body and wing movements by high-speed cameras. The 3AXM was activated with 1 to 3 spikes per each wingbeat cycle but sometimes ceased to fire. The phase of the onset of the activities was, even though it was variable, close to the phase of the elevator muscle activities. Therefore the upper unit of the 3AXM activities would affect upstroke properties phasically including wing retractions. We focused on longitudinal flight control and identified a correlation between the phase of the 3AXM and body pitch angle, which is important kinematical parameter for longitudinal control in insect flight. The phasic changes of the 3AXM activities would support quick changes in longitudinal control. PMID:14993822
InAs/GaSb type II superlattices for advanced 2nd and 3rd generation detectors
NASA Astrophysics Data System (ADS)
Walther, Martin; Rehm, Robert; Schmitz, Johannes; Fleissner, Joachim; Rutz, Frank; Kirste, Lutz; Scheibner, Ralf; Wendler, Joachim; Ziegler, Johann
2010-01-01
InAs/GaSb short-period superlattices (SL) based on GaSb, InAs and AlSb have proven their great potential for high performance infrared detectors. Lots of interest is currently focused on the development of short-period InAs/GaSb SLs for advanced 2nd and 3rd generation infrared detectors between 3 - 30 μm. For the fabrication of mono- and bispectral thermal imaging systems in the mid-wavelength infrared region (MWIR) a manufacturable technology for high responsivity thermal imaging systems has been developed. InAs/GaSb short-period superlattices can be fabricated with up to 1000 periods in the intrinsic region without revealing diffusion limited behavior. This enables the fabrication of InAs/GaSb SL camera systems with high responsivity comparable to state of the art CdHgTe and InSb detectors. The material system is also ideally suited for the fabrication of dual-color MWIR/MWIR InAs/GaSb SL camera systems with high quantum efficiency for missile approach warning systems with simultaneous and spatially coincident detection in both spectral channels.
Rajak, Prem; Dutta, Moumita
2015-01-01
Acephate, an organophosphate (OP) pesticide, was used to investigate the effects of its chronic exposure on hemocyte abundance in a non-target dipteran insect Drosophila melanogaster. For this purpose, six graded concentrations ranging from 1 to 6 μg/ml were selected, which are below the reported residual values (up to 14 μg/ml) of the chemical. 1st instar larvae were fed with these concentrations up to the 3rd instar stage and accordingly hemolymph smears from these larvae were prepared for differential hemocyte count. Three types of cells are found in Drosophila hemolymph, namely, plasmatocytes, lamellocytes and crystal cells. Plasmatocyte count was found to decrease with successive increase in treatment concentrations. Crystal cells showed an increasing trend in their number. Though the number of lamellocytes was very low, a bimodal response was noticed. Lamellocyte number was found to increase with the initial three concentrations, followed by a dose dependent reduction in their number. As hemocytes are directly linked to the immune system of fruit flies, fluctuations in normal titer of these cells may affect insect immunity. Hemocytes share homologies in their origin and mode of action with the immune cells of higher organisms including man. Thus the present findings suggest that immune cells of humans and other organisms may be affected adversely under chronic exposure to Acephate. PMID:27486365
ERIC Educational Resources Information Center
Fisher, Allison; Lange, Mary Anne; Young-Cureton, Virginia; Canham, Daryl
2005-01-01
Very little is known about body satisfaction among minority children. This study examined the relationship between perceived and actual body size and Body Mass Index among 43 low-socioeconomic Hispanic 3rd-graders. Researchers measured participants' Body Mass Index; students self-reported Perceived Ideal Self Image and Perceived Actual Self Image…
ERIC Educational Resources Information Center
Deafblind International, London (England).
This text includes all of the plenary presentations from the 3rd European Conference of Deafblind International's Acquired Deafblindness Network. This international conference was the first to focus specifically on older people with dual sensory impairment. Presentations addressed the awareness of the needs of older people with deafblind or dual…
ERIC Educational Resources Information Center
Woodruff, Asahel; Froyen, Len
This report of the proceedings of the 3rd Annual Professional Education Seminar of the Central States Colleges and Universities centers upon the implications of technology for teaching and learning and contains addresses delivered, including "Some Concerns Related to Technology in Education," by Len Froyen; and "Implications of Technology for…
ERIC Educational Resources Information Center
Gaylor, Erika; Spiker, Donna; Wei, Xin; Lease, Erin; Reynolds, Arthur
2015-01-01
This presentation reports on the goals and preliminary outcomes of the Child-Parent Centers (CPC) Expansion Project, which is a PreK to 3rd grade school reform model aimed at improving the short- and long-term outcomes of participating children and families. The model provides continuous education and family support services to schools serving a…
Nonlinear singularly perturbed optimal control problems with singular arcs
NASA Technical Reports Server (NTRS)
Ardema, M. D.
1977-01-01
A third order, nonlinear, singularly perturbed optimal control problem is considered under assumptions which assure that the full problem is singular and the reduced problem is nonsingular. The separation between the singular arc of the full problem and the optimal control law of the reduced one, both of which are hypersurfaces in state space, is of the same order as the small parameter of the problem. Boundary layer solutions are constructed which are stable and reach the outer solution in a finite time. A uniformly valid composite solution is then formed from the reduced and boundary layer solutions. The value of the approximate solution is that it is relatively easy to obtain and does not involve singular arcs. To illustrate the utility of the results, the technique is used to obtain an approximate solution of a simplified version of the aircraft minimum time-to-climb problem. A numerical example is included.
Holographic signatures of cosmological singularities.
Engelhardt, Netta; Hertog, Thomas; Horowitz, Gary T
2014-09-19
To gain insight into the quantum nature of cosmological singularities, we study anisotropic Kasner solutions in gauge-gravity duality. The dual description of the bulk evolution towards the singularity involves N=4 super Yang-Mills theory on the expanding branch of deformed de Sitter space and is well defined. We compute two-point correlators of Yang-Mills operators of large dimensions using spacelike geodesics anchored on the boundary. The correlators show a strong signature of the singularity around horizon scales and decay at large boundary separation at different rates in different directions. More generally, the boundary evolution exhibits a process of particle creation similar to that in inflation. This leads us to conjecture that information on the quantum nature of cosmological singularities is encoded in long-wavelength features of the boundary wave function.
Singularity Resolution in Quantum Gravity
NASA Astrophysics Data System (ADS)
Singh, Parampreet
2014-03-01
In recent years, progress in understanding of the quantization of cosmological spacetimes using techniques of loop quantum gravity, has led to important insights on the resolution of singularities. With a rigorous loop quantization of isotropic and anisotropic spacetimes and development of sophisticated numerical techniques, it is now possible to explore in detail the structure of spacetime in the Planck regime and extract new physics of the very early universe. Investigations of quantization of various spacetimes indicates that classical singularities such as the big bang are avoided, and quantum evolution results in a bounce of the scale factor. The resolution of singularities seems to occur without any assumption on the initial state for quantum evolution or the equation of state of matter. In this talk, we will review some of the main developments in this direction and provide an up to date summary of the novel results obtained on the resolution of singularities in various models in loop quantum gravity.
Visibility of a spacetime singularity
Joshi, Pankaj S.
2007-02-15
We investigate here the causal structure of spacetime in the vicinity of a spacetime singularity. The particle and energy emission from such ultradense regions forming in gravitational collapse of a massive matter cloud is governed by the nature of nonspacelike paths near the same. These trajectories are examined to show that if a null geodesic comes out from the singularity, then there exist families of future-directed nonspacelike curves which also necessarily escape from the same. The existence of such families is crucial to the physical visibility of the singularity. We do not assume any underlying symmetries for the spacetime, and earlier considerations on the nature of causal trajectories emerging from a naked singularity are generalized and clarified.
Göktalay, Tuğba; Cengiz Özyurt, Beyhan; Sakar Coşkun, Ayşin; Celik, Pinar
2011-01-01
The levels of smoking of 1st and 2nd year students at Faculty of Medicine and Manisa School of Health at Celal Bayar University were investigated in 2006-2007. This study is carried out in order to see if there is a change in the same students' level of smoking while they are in 3rd and 4th year. In addition, the study aimed to examine the factors affecting the level of use and attitudes towards the law effectuated in July 19, 2009. This is a follow-up study with 80.42% return rate. A 26-item structured questionnaire was administered. The participants filled out the questionnaires under supervision of the researchers in their classrooms. The University Institutional Review Board approved the study. The total of participants (263) of the follow-up study included 189 female and 74 male. The rate of experimenting with smoking was 49% with the mean age of 15.7 (SD= 4.01 years). The mean age of experimenting with smoking was the earliest on male students studying at faculty of medicine. The level of smoking was found to be the most on females, studying at faculty of medicine and staying at the dormitory, with smoking parents (p< 0.05). The most important reason to begin smoking was curiosity (55.2%) while bad breath and yellowing of teeth were the reasons to quit (91.7%). 83.3% of the students thought that the law will be effective on quit smoking. The level of both experimenting and use of smoking has been increased over time. It is suggested that medical students' awareness about the danger of smoking should be raised at earlier grades. In addition, lectures should be offered to students at School of Health and they should be encouraged to unite in order to fight with smoking.
Miyazaki, Masaru; Ohtsuka, Masayuki; Miyakawa, Shuichi; Nagino, Masato; Yamamoto, Masakazu; Kokudo, Norihiro; Sano, Keiji; Endo, Itaru; Unno, Michiaki; Chijiiwa, Kazuo; Horiguchi, Akihiko; Kinoshita, Hisafumi; Oka, Masaaki; Kubota, Keiichi; Sugiyama, Masanori; Uemoto, Shinji; Shimada, Mitsuo; Suzuki, Yasuyuki; Inui, Kazuo; Tazuma, Susumu; Furuse, Junji; Yanagisawa, Akio; Nakanuma, Yasuni; Kijima, Hiroshi; Takada, Tadahiro
2015-03-01
The 3(rd) English edition of the Japanese classification of biliary tract cancers was released approximately 10 years after the 5(th) Japanese edition and the 2(nd) English edition. Since the first Japanese edition was published in 1981, the Japanese classification has been in extensive use, particularly among Japanese surgeons and pathologists, because the cancer status and clinical outcomes in surgically resected cases have been the main objects of interest. However, recent advances in the diagnosis, management and research of the disease prompted the revision of the classification that can be used by not only surgeons and pathologists but also by all clinicians and researchers, for the evaluation of current disease status, the determination of current appropriate treatment, and the future development of medical practice for biliary tract cancers. Furthermore, during the past 10 years, globalization has advanced rapidly, and therefore, internationalization of the classification was an important issue to revise the Japanese original staging system, which would facilitate to compare the disease information among institutions worldwide. In order to achieve these objectives, the new Japanese classification of the biliary tract cancers principally adopted the 7(th) edition of staging system developed by the International Union Against Cancer (UICC) and the American Joint Committee on Cancer (AJCC). However, because there are some points pending in these systems, several distinctive points were also included for the purpose of collection of information for the future optimization of the staging system. Free mobile application of the new Japanese classification of the biliary tract cancers is available via http://www.jshbps.jp/en/classification/cbt15.html. PMID:25691463
Göktalay, Tuğba; Cengiz Özyurt, Beyhan; Sakar Coşkun, Ayşin; Celik, Pinar
2011-01-01
The levels of smoking of 1st and 2nd year students at Faculty of Medicine and Manisa School of Health at Celal Bayar University were investigated in 2006-2007. This study is carried out in order to see if there is a change in the same students' level of smoking while they are in 3rd and 4th year. In addition, the study aimed to examine the factors affecting the level of use and attitudes towards the law effectuated in July 19, 2009. This is a follow-up study with 80.42% return rate. A 26-item structured questionnaire was administered. The participants filled out the questionnaires under supervision of the researchers in their classrooms. The University Institutional Review Board approved the study. The total of participants (263) of the follow-up study included 189 female and 74 male. The rate of experimenting with smoking was 49% with the mean age of 15.7 (SD= 4.01 years). The mean age of experimenting with smoking was the earliest on male students studying at faculty of medicine. The level of smoking was found to be the most on females, studying at faculty of medicine and staying at the dormitory, with smoking parents (p< 0.05). The most important reason to begin smoking was curiosity (55.2%) while bad breath and yellowing of teeth were the reasons to quit (91.7%). 83.3% of the students thought that the law will be effective on quit smoking. The level of both experimenting and use of smoking has been increased over time. It is suggested that medical students' awareness about the danger of smoking should be raised at earlier grades. In addition, lectures should be offered to students at School of Health and they should be encouraged to unite in order to fight with smoking. PMID:22233305
S., Chandrasekharappa; Brid, S.V
2014-01-01
Background: Pregnancy although a physiological phenomena affects all the functions of the maternal body and brings about remarkable changes in the cardiovascular system. The cardiovascular changes and many of the physiological adaptations of normal pregnancy alter the physical findings thus, sometimes misleading the diagnosis of heart disease. Pregnancy also brings about various changes in the electrocardiogram, further confusing with that of heart disease. This study is undertaken to highlight the effect of normal pregnancy on the QRS axis, Q wave and T-wave of the Electrocardiogram and thereby helps us to distinguish it from that of pathological changes. Objectives: To study the effect of normal pregnancy on the QRS axis, Q wave and T-wave in the electrocardiogram and to compare with that of normal non pregnant women. Materials and Methods: Fifty normal pregnant women in 2nd and 3rd trimester each between 20– 35 y of age and 50 normal non pregnant women of the same age group were selected for the study. A 12 lead ECG was recorded by using ECG machine with special emphasis on QRS axis, Q wave and T-wave changes and all the parameters were analysed. Results: The ECG changes observed in our study include, deviation of QRS axis towards left as pregnancy advanced, significant increased incidence of occurrence of prominent Q waves in lead II, III and avF in pregnant group (p < 0.05 ) and, T-wave abnormalities like flat and inverted T-waves in lead III, V1 – V3 were more frequent in pregnant group ( p<0.05 ) than in non pregnant group. Conclusion:Normal pregnancy brings about various changes in ECG. These changes during pregnancy should be interpretated with caution by the physicians. It is necessary to understand the normal physiological changes which in turn help us in better management of those with cardiac disease. PMID:25386425
Miyazaki, Masaru; Ohtsuka, Masayuki; Miyakawa, Shuichi; Nagino, Masato; Yamamoto, Masakazu; Kokudo, Norihiro; Sano, Keiji; Endo, Itaru; Unno, Michiaki; Chijiiwa, Kazuo; Horiguchi, Akihiko; Kinoshita, Hisafumi; Oka, Masaaki; Kubota, Keiichi; Sugiyama, Masanori; Uemoto, Shinji; Shimada, Mitsuo; Suzuki, Yasuyuki; Inui, Kazuo; Tazuma, Susumu; Furuse, Junji; Yanagisawa, Akio; Nakanuma, Yasuni; Kijima, Hiroshi; Takada, Tadahiro
2015-03-01
The 3(rd) English edition of the Japanese classification of biliary tract cancers was released approximately 10 years after the 5(th) Japanese edition and the 2(nd) English edition. Since the first Japanese edition was published in 1981, the Japanese classification has been in extensive use, particularly among Japanese surgeons and pathologists, because the cancer status and clinical outcomes in surgically resected cases have been the main objects of interest. However, recent advances in the diagnosis, management and research of the disease prompted the revision of the classification that can be used by not only surgeons and pathologists but also by all clinicians and researchers, for the evaluation of current disease status, the determination of current appropriate treatment, and the future development of medical practice for biliary tract cancers. Furthermore, during the past 10 years, globalization has advanced rapidly, and therefore, internationalization of the classification was an important issue to revise the Japanese original staging system, which would facilitate to compare the disease information among institutions worldwide. In order to achieve these objectives, the new Japanese classification of the biliary tract cancers principally adopted the 7(th) edition of staging system developed by the International Union Against Cancer (UICC) and the American Joint Committee on Cancer (AJCC). However, because there are some points pending in these systems, several distinctive points were also included for the purpose of collection of information for the future optimization of the staging system. Free mobile application of the new Japanese classification of the biliary tract cancers is available via http://www.jshbps.jp/en/classification/cbt15.html.
Naked singularity resolution in cylindrical collapse
Kurita, Yasunari; Nakao, Ken-ichi
2006-03-15
In this paper, we study the gravitational collapse of null dust in cylindrically symmetric spacetime. The naked singularity necessarily forms at the symmetry axis. We consider the situation in which null dust is emitted again from the naked singularity formed by the collapsed null dust and investigate the backreaction by this emission for the naked singularity. We show a very peculiar but physically important case in which the same amount of null dust as that of the collapsed one is emitted from the naked singularity as soon as the ingoing null dust hits the symmetry axis and forms the naked singularity. In this case, although this naked singularity satisfies the strong curvature condition by Krolak (limiting focusing condition), geodesics which hit the singularity can be extended uniquely across the singularity. Therefore, we may say that the collapsing null dust passes through the singularity formed by itself and then leaves for infinity. Finally, the singularity completely disappears and the flat spacetime remains.
Personalized Messages That Promote Science Learning in Virtual Environments
ERIC Educational Resources Information Center
Moreno, Roxana; Mayer, Richard E.
2004-01-01
College students learned how to design the roots, stem, and leaves of plants to survive in five different virtual reality environments through an agent-based multimedia educational game. For each student, the agent used personalized speech (e.g., including I and you) or nonpersonalized speech (e.g., 3rd-person monologue), and the game was…
Iglesias, L; Valero, A; Gálvez, L; Benítez, R; Adroher, F J
2002-11-01
This is the first demonstration of the in vitro development of the 3rd-stage larvae (L3) of Hysterothylacium aduncum to the adult. This was achieved in a semi-defined medium that is easy to prepare and to reproduce. The L3, collected from the peritoneal cavity of horse mackerel (Trachurus trachurus), were individually inoculated into RPMI-1640 medium +20% heat-inactivated fetal bovine serum (IFBS). It has been demonstrated that the optimum temperature for development is around 13 degrees C and is stimulated by the presence of 5% CO2 in the growth atmosphere, increasing the percentage moulting to the 4th larval stage (L4) by 1.9-fold (from 44 to 82%) and the average survival of the nematodes by 1.6 times (from 60 to 96 days). When the larvae were grown at different pHs, optimum development occurred at pH 4.0. Under these conditions, all the larvae moulted to the L4 and more than two-thirds transformed to the adult stage--in which 25-30% of the females laid eggs--and reached an average survival of over 4 months. When this medium was supplemented with 1% (w/v) of commercial pepsin, all the larvae reached the adult stage, at least 45% of the females oviposited, laying around 12-fold more eggs per female than in the medium without pepsin. The mean size of the eggs (non-fertilized) obtained was 56.8 x 47.6 microm. The mean length of the adult males obtained was between 3.2 and 5.2 cm and the females were between 3.0 and 6.5 cm. The adult specimens were morphologically identified as Hysterothylacium aducum aduncum. This culture medium (RPMI-1640+20% (v/v) IFBS+1 commercial pepsin, at pH 4.0, 13 degrees C and 5% CO2 in air) could facilitate the identification of at least some of the larvae of the genus Hysterothylacium--and perhaps other anisakids--for which the specific identification and the biological study of these parasites is often difficult. PMID:12458831
NASA Astrophysics Data System (ADS)
Gaol, F. L.
2016-02-01
The 3rd International Conferences on Geological, Geographical, Aerospaces and Earth Sciences 2015 (AeroEarth 2015), was held at The DoubleTree Hilton, Jakarta, Indonesia during 26 - 27 September 2015. The 1st AeoroEarth was held succefully in Jakarta in 2013. The success continued to The 2nd AeroEarth 2014 that was held in Kuta Bali, Indonesia. The publications were published by EES IOP in http://iopscience.iop.org/1755-1315/19/1 and http://iopscience.iop.org/1755-1315/23/1 respectively. The AeroEarth 2015 conference aims to bring together researchers, engineers and scientists from around the world. Through research and development, Earth's scientists have the power to preserve the planet's different resource domains by providing expert opinion and information about the forces which make life possible on Earth. The theme of AeroEarth 2015 is ''Earth and Aerospace Sciences : Challenges and Opportunities'' Earth provides resources and the exact conditions to make life possible. However, with the advent of technology and industrialization, the Earth's resources are being pushed to the brink of depletion. Non-sustainable industrial practices are not only endangering the supply of the Earth's natural resources, but are also putting burden on life itself by bringing about pollution and climate change. A major role of earth science scholars is to examine the delicate balance between the Earth's resources and the growing demands of industrialization. Through research and development, earth scientists have the power to preserve the planet's different resource domains by providing expert opinion and information about the forces which make life possible on Earth. We would like to express our sincere gratitude to all in the Technical Program Committee who have reviewed the papers and developed a very interesting Conference Program as well as the invited and plenary speakers. This year, we received 78 papers and after rigorous review, 18 papers were accepted. The participants
Crouter, Scott E.; de Ferranti, Sarah D.; Whiteley, Jessica; Steltz, Sarah K.; Osganian, Stavroula K.; Feldman, Henry A.; Hayman, Laura L.
2015-01-01
Background Less than 45% of U.S. children meet the 60 min.d-1 physical activity (PA) guideline. Structured after-school PA programing is one approach to help increase activity levels. This study aimed to evaluate the feasibility and short-term impact of a supervised after-school PA and nutrition education program on activity levels. Methods Forty-two 3rd-5th graders from an inner-city school in Boston, MA were randomly assigned to a 10-wk after-school program of either: 1) weekly nutrition education, or 2) weekly nutrition education plus supervised PA 3 d.wk-1 at a community-based center. At baseline and follow-up, PA was measured using accelerometry and fitness (VO2max) was estimated using the PACER 15-m shuttle run. Additional measures obtained were non-fasting finger stick total cholesterol (TC) and glucose levels, waist circumference (WC), body mass index (BMI), percent body fat (%BF), and blood pressure (BP). Values are presented as mean±SE, unless noted otherwise. Results Thirty-six participants completed the study (mean±SD; age 9.7±0.9 years). Participants attended >80% of the sessions. After adjusting for accelerometer wear time and other design factors, light and moderate-to-vigorous PA (MVPA) increased in the nutrition+PA group (+21.5±14.5 and +8.6±8.0 min.d-1, respectively) and decreased in the nutrition only group (-35.2±16.3 and -16.0±9.0 min.d-1, respectively); mean difference between groups of 56.8±21.7 min.d-1 (light PA, p = 0.01) and 24.5±12.0 min.d-1 (MVPA, p = 0.04). Time spent in sedentary behaviors declined in the nutrition+PA group (-14.8±20.7 min.d-1) and increased in the nutrition only group (+55.4±23.2 min.d-1); mean difference between groups of -70.2±30.9 min.d-1 (p = 0.02). Neither group showed changes in TC, BP, WC, %BF, BMI percentile, or fitness (p>0.05). Conclusions The supervised afterschool community-based nutrition and PA program was well accepted and had high attendance. The changes in light PA and MVPA has potential
NASA Astrophysics Data System (ADS)
Gaol, F. L.
2015-06-01
The 3rd International Conference on Science & Engineering in Mathematics, Chemistry and Physics 2015 (ScieTech 2015), was held at The Westin Resort Nusa Dua, Bali on 31 January - 1 February 2015. The ScieTech 2015 conference is aimed to bring together researchers, engineers and scientists from around the world. ScieTech 2015 is placed on promoting interaction between the theoretical, experimental, and applied communities, so that a high level exchange is achieved in new and emerging areas within mathematics, chemistry and physics. As we already know that science and technology have brought tremendous benefits for human civilization. People are becoming healthier, wealthier, better educated, more peaceful, increasingly connected, and living longer. Of course, science and technology provide many answers to global challenges, but we will face more complex problems in the next decade due to increasing world population, limitation of energy, and climate change. Therefore, researchers should be more active in conducting research that enables collaboration between one and the others. Interdisciplinary cooperation is absolutely necessary in order to create a smart system for solving the global problems. We need a global and general long-term view of the future with long-range goals for solving complex problems in next decade. Therefore the conference was held to be a forum for researchers from different disciplines to start collaborating and conducting research that provides a solution to the global issues. The theme of ScieTech 2015 was ''The interdisciplinary Application between Mathematics, Chemistry and Physics to enhance the Quality of Life''. We would like to express our sincere gratitude to all in the Technical Program Committee who have reviewed the papers and developed a very interesting conference program as well as the invited and plenary speakers. This year, we received 197 papers and after rigorous review, 59 papers were accepted. The participants came from 19
Naked singularities as particle accelerators
Patil, Mandar; Joshi, Pankaj S.
2010-11-15
We investigate here the particle acceleration by naked singularities to arbitrarily high center of mass energies. Recently it has been suggested that black holes could be used as particle accelerators to probe the Planck scale physics. We show that the naked singularities serve the same purpose and probably would do better than their black hole counterparts. We focus on the scenario of a self-similar gravitational collapse starting from a regular initial data, leading to the formation of a globally naked singularity. It is seen that when particles moving along timelike geodesics interact and collide near the Cauchy horizon, the energy of collision in the center of mass frame will be arbitrarily high, thus offering a window to Planck scale physics.
Optimal singular control for nonlinear semistabilisation
NASA Astrophysics Data System (ADS)
L'Afflitto, Andrea; Haddad, Wassim M.
2016-06-01
The singular optimal control problem for asymptotic stabilisation has been extensively studied in the literature. In this paper, the optimal singular control problem is extended to address a weaker version of closed-loop stability, namely, semistability, which is of paramount importance for consensus control of network dynamical systems. Three approaches are presented to address the nonlinear semistable singular control problem. Namely, a singular perturbation method is presented to construct a state-feedback singular controller that guarantees closed-loop semistability for nonlinear systems. In this approach, we show that for a non-negative cost-to-go function the minimum cost of a nonlinear semistabilising singular controller is lower than the minimum cost of a singular controller that guarantees asymptotic stability of the closed-loop system. In the second approach, we solve the nonlinear semistable singular control problem by using the cost-to-go function to cancel the singularities in the corresponding Hamilton-Jacobi-Bellman equation. For this case, we show that the minimum value of the singular performance measure is zero. Finally, we provide a framework based on the concepts of state-feedback linearisation and feedback equivalence to solve the singular control problem for semistabilisation of nonlinear dynamical systems. For this approach, we also show that the minimum value of the singular performance measure is zero. Three numerical examples are presented to demonstrate the efficacy of the proposed singular semistabilisation frameworks.
Dimensional mutation and spacelike singularities
Silverstein, Eva
2006-04-15
I argue that string theory compactified on a Riemann surface crosses over at small volume to a higher dimensional background of supercritical string theory. Several concrete measures of the count of degrees of freedom of the theory yield the consistent result that at finite volume, the effective dimensionality is increased by an amount of order 2h/V for a surface of genus h and volume V in string units. This arises in part from an exponentially growing density of states of winding modes supported by the fundamental group, and passes an interesting test of modular invariance. Further evidence for a plethora of examples with the spacelike singularity replaced by a higher dimensional phase arises from the fact that the sigma model on a Riemann surface can be naturally completed by many gauged linear sigma models, whose RG flows approximate time evolution in the full string backgrounds arising from this in the limit of large dimensionality. In recent examples of spacelike singularity resolution by tachyon condensation, the singularity is ultimately replaced by a phase with all modes becoming heavy and decoupling. In the present case, the opposite behavior ensues: more light degrees of freedom arise in the small radius regime. We comment on the emerging zoology of cosmological singularities that results.
Singularities of quantum control landscapes
NASA Astrophysics Data System (ADS)
Wu, Re-Bing; Long, Ruixing; Dominy, Jason; Ho, Tak-San; Rabitz, Herschel
2012-07-01
Quantum control landscape theory was formulated to assess the ease of finding optimal control fields in simulations and in the laboratory. The landscape is the observable as a function of the controls, and a primary goal of the theory is the analysis of landscape features. In what is referred to as the kinematic picture of the landscape, prior work showed that the landscapes are generally free of traps that could halt the search for an optimal control at a suboptimal observable value. The present paper considers the dynamical picture of the landscape, seeking the existence of singular controls, especially of a nonkinematic nature along with an assessment of whether they correspond to traps. We analyze the necessary and sufficient conditions for singular controls to be kinematic or nonkinematic critical solutions and the likelihood of their being encountered while maximizing an observable. An algorithm is introduced to seek singular controls on the landscape in simulations along with an associated Hessian landscape analysis. Simulations are performed for a large number of model finite-level quantum systems, showing that all the numerically identified kinematic and nonkinematic singular critical controls are not traps, in support of the prior empirical observations on the ease of finding high-quality optimal control fields.
Specialty functions singularity mechanics problems
NASA Technical Reports Server (NTRS)
Sarigul, Nesrin
1989-01-01
The focus is in the development of more accurate and efficient advanced methods for solution of singular problems encountered in mechanics. At present, finite element methods in conjunction with special functions, boolean sum and blending interpolations are being considered. In dealing with systems which contain a singularity, special finite elements are being formulated to be used in singular regions. Further, special transition elements are being formulated to couple the special element to the mesh that models the rest of the system, and to be used in conjunction with 1-D, 2-D and 3-D elements within the same mesh. Computational simulation with a least squares fit is being utilized to construct special elements, if there is an unknown singularity in the system. A novel approach is taken in formulation of the elements in that: (1) the material properties are modified to include time, temperature, coordinate and stress dependant behavior within the element; (2) material properties vary at nodal points of the elements; (3) a hidden-symbolic computation scheme is developed and utilized in formulating the elements; and (4) special functions and boolean sum are utilized in order to interpolate the field variables and their derivatives along the boundary of the elements. It may be noted that the proposed methods are also applicable to fluids and coupled problems.
Frozen singularities in M and F theory
NASA Astrophysics Data System (ADS)
Tachikawa, Yuji
2016-06-01
We revisit the duality between ALE singularities in M-theory and 7-branes on a circle in F-theory. We see that a frozen M-theory singularity maps to a circle compactification involving a rotation of the plane transverse to the 7-brane, showing an interesting correspondence between commuting triples in simply-laced groups and Kodaira's classification of singular elliptic fibrations. Our analysis strongly suggests that the O7+ plane is the only completely frozen F-theory singularity.
ERIC Educational Resources Information Center
United Nations Educational, Scientific and Cultural Organization, Paris (France). General Information Programme.
Participants in the meeting summarized in this report advised and made recommendations on appropriate activities and programs conducive to the development of cooperative networks and the exchange of information and experience in science and technology in the Asia Pacific Region. Invited in their personal capacity as experts, the 14 participants…
ERIC Educational Resources Information Center
Rado, Marta, Ed.
The conference was held to alert teachers and other interested persons to the complexities of linguistic diversity in Australia, with attention focused on the immigrant child. This report includes the individual conference papers, presented by Marta Rado, Bert Townsend, Michael Clyne, Alan Matheson, and Rede Lar, and the comments of symposium and…
Properties of a Two-Sphere Singularity
NASA Astrophysics Data System (ADS)
Konkowski, Deborah A.; Helliwell, Thomas M.
2015-01-01
Recently Böhmer and Lobo have shown that a metric due to Florides can be extended to reveal a classical singularity that has the form of a two-sphere. Here we discuss and expand on the classical singularity properties and then show the classical singularity is not healed by a quantum analysis.
Forrai, Gábor; Ambrózay, Éva; Bidlek, Mária; Borbély, Katalin; Kovács, Eszter; Lengyel, Zsolt; Ormándi, Katalin; Péntek, Zoltán; Riedl, Erika; Sebõ, Éva; Szabó, Éva
2016-09-01
Breast radiologists and nuclear medical specialists have refreshed their previous statement text during the 3rd Hungarian Breast Cancer Consensus Meeting. They suggest taking into consideration this actual protocol for the screening, diagnostics and treatment of breast tumors, from now on. This recommendation includes the description of the newest technologies, the recent results of scientific research, as well as the role of imaging methods in the therapeutic processes and the follow-up. Suggestions for improvement of the Hungarian current practice and other related issues as forensic medicine, media connections, regulations, and reimbursement are also detailed. The statement text has been cross-checked with the related medical disciplines. PMID:27579719
ERIC Educational Resources Information Center
Bell, William G., Ed.; Ashford, Norman J., Ed.
These conference proceedings contain the texts of 62 papers. The first 17 papers include 4 keynote presentations as well as reviews of: major developments in several countries (Brazil, Canada, Great Britain, Jordan, Netherlands, Sweden, United States) and Hong Kong; handicapped travelers' access to air transport; and application of microcomputer…
ERIC Educational Resources Information Center
Tmej, K., Ed.; Petracek, S., Ed.
A need for concerted efforts in devising a more profound socialist education for the younger generation, and a strengthening of ideological ties joining the socialist nations was revealed in conference papers on: (1) the conference's significance (K. Tmej); (2) inaugural address (J. Kuberski); (3) Marxism-Leninism on the task of schools and…
G 2-Monopoles with Singularities (Examples)
NASA Astrophysics Data System (ADS)
Oliveira, Goncalo
2016-08-01
G 2-Monopoles are solutions to gauge theoretical equations on G 2-manifolds. If the G 2-manifolds under consideration are compact, then any irreducible G 2-monopole must have singularities. It is then important to understand which kind of singularities G 2-monopoles can have. We give examples (in the noncompact case) of non-Abelian monopoles with Dirac type singularities, and examples of monopoles whose singularities are not of that type. We also give an existence result for Abelian monopoles with Dirac type singularities on compact manifolds. This should be one of the building blocks in a gluing construction aimed at constructing non-Abelian ones.
Cancellation of singularities for synthetic aperture radar
NASA Astrophysics Data System (ADS)
Caday, Peter
2015-01-01
In a basic model for synthetic aperture radar (SAR) imaging, one wishes to recover a function or distribution f from line integrals over circles whose centers lie on a given curve γ. In this paper, we consider the problem of recovering the singularities (wavefront set) of f given its SAR data, and specifically whether it is possible to choose a singular f whose singularities are hidden from γ, meaning that its SAR data is smooth. We show that f 's singularities can be hidden to leading order if a certain discrete reflection map is the identity, and give examples where this is the case. Finally, numerical experiments illustrate the hiding of singularities.
Naked singularity and a thunderbolt
NASA Astrophysics Data System (ADS)
Ishibashi, Akihiro; Hosoya, Akio
2002-11-01
We consider the quantum theoretical effects of a sudden change of boundary conditions which mimics the occurrence of naked singularities. For a simple demonstration, we study a massless scalar field in (1+1)-dimensional Minkowski spacetime with a finite spatial interval. We calculate the vacuum expectation value of the energy-momentum tensor and explicitly show that singular wave or thunderbolt appears along the Cauchy horizon. The thunderbolt possibly destroys the Cauchy horizon if its back reaction on the geometry is taken into account, leading to quantum restoration of the global hyperbolicity. The result of the present work may also apply to the situation where a closed string freely oscillating is traveling to a brane and changes itself to an open string pinned down by the ends, satisfying the Dirichlet boundary conditions on the brane.
NASA Astrophysics Data System (ADS)
Ortiz, Néstor; Sarbach, Olivier; Zannias, Thomas
2015-08-01
We analyze the redshift suffered by photons originating from an external source, traversing a collapsing dust cloud, and finally being received by an asymptotic observer. In addition, we study the shadow that the collapsing cloud casts on the sky of the asymptotic observer. We find that the resulting redshift and properties of the shadow depend crucially on whether the final outcome of the complete gravitational collapse is a black hole or a naked singularity. In the black hole case, the shadow is due to the high redshift acquired by the photons as they approach the event horizon, implying that their energy is gradually redshifted toward zero within a few crossing times associated with the event horizon radius. In contrast to this, a naked singularity not only absorbs photons originating from the source, but it also emits infinitely redshifted photons with and without angular momenta. This emission introduces an abrupt cutoff in the frequency shift of the photons detected in directions close to the radial one, and it is responsible for the shadow masking the source in the naked singularity case. Furthermore, even though the shadow forms and begins to grow immediately after the observer crosses the Cauchy horizon, it takes many more crossing times than in the black hole case for the source to be occulted from the observer's eyes. We discuss possible implications of our results for testing the weak cosmic censorship hypothesis. Even though at late times the image of the source perceived by the observer looks the same in both cases, the dynamical formation of the shadow and the redshift images has distinct features and time scales in the black hole versus the naked singularity case. For stellar collapse, these time scales seem to be too short to be resolved with existing technology. However, our results may be relevant for the collapse of seeds leading to supermassive black holes.
Singular perturbation of absolute stability.
NASA Technical Reports Server (NTRS)
Siljak, D. D.
1972-01-01
It was previously shown (author, 1969) that the regions of absolute stability in the parameter space can be determined when the parameters appear on the right-hand side of the system equations, i.e., the regular case. Here, the effect on absolute stability of a small parameter attached to higher derivatives in the equations (the singular case) is studied. The Lur'e-Postnikov class of nonlinear systems is considered.
Splash singularity for water waves
Castro, Angel; Córdoba, Diego; Fefferman, Charles L.; Gancedo, Francisco; Gómez-Serrano, Javier
2012-01-01
We exhibit smooth initial data for the two-dimensional (2D) water-wave equation for which we prove that smoothness of the interface breaks down in finite time. Moreover, we show a stability result together with numerical evidence that there exist solutions of the 2D water-wave equation that start from a graph, turn over, and collapse in a splash singularity (self-intersecting curve in one point) in finite time. PMID:22219372
The singularity of being: Lacan and the immortal within.
Ruti, Mari
2010-12-01
Drawing on the work of Eric Santner, Slavoj Žižek, and Alenka Zupančič, this paper constructs a theory of subjective singularity from a Lacanian perspective. It argues that, unlike the "subject" (who comes into existence as a result of symbolic prohibition), or the "person" (who is aligned with the narcissistic conceits of the imaginary), the singular self emerges in response to a galvanizing directive arising from the real. This directive summons the individual to a "character" beyond his or her social and intersubjective investments. Consequently, singularity expresses the individual's nonnegotiable distinctiveness, eccentricity, or idiosyncrasy at the same time as it prevents both symbolic and imaginary closure. It opens to layers of rebelliousness that indicate that there are components of human life that exceed the realm of normative sociality. Indeed, insofar as singularity articulates something about the "undead" pulse of jouissance, it connects the individual to a paradoxical kind of immortality. This does not mean that the individual will not die, but rather that he or she is capable of "transcendent" experiences, such as heightened states of creativity, that (always momentarily) reach "outside" the parameters of mortal life. Such experiences allow the individual to feel "real" in ways that fend off symbolic abduction and psychic death.
Initial directional singularity in inflationary models
NASA Astrophysics Data System (ADS)
Fernández-Jambrina, L.
2016-07-01
In Haro, Amorós, and Pan [Phys. Rev. D 93, 084018 (2016)] a new cosmological model is proposed with no big bang singularity in the past, though past geodesically incomplete. This model starts with an inflationary era, follows with a stiff matter dominated period and evolves to accelerated expansion in an asymptotically de Sitter regime in a realistic fashion. The big bang singularity is replaced by a directional singularity. This singularity cannot be reached by comoving observers, since it would take them an infinite proper time lapse to go back to it. On the contrary, observers with nonzero linear momentum have the singularity at finite proper time in their past, though arbitrarily large. Hence, the time lapse from the initial singularity can be as long as desired, even infinity, depending on the linear momentum of the observer. This conclusion applies to similar inflationary models. Due to the interest of these models, we address here the properties of such singularities.
Nemcovsky, C E; Libfeld, H; Zubery, Y
1996-09-01
Root resorption of 2nd molars in proximity to non-erupted 3rd molars has been widely reported. The purpose of this study was to determine the prevalence of root resorption in second molars adjacent to non-erupted third molars. Its association to age and gender of the patient, location and inclination of the non-erupted third molar and to distal bone support of the 2nd molars was analyzed. A radiographic survey of 202 periapical radiographs taken in patients with clinically missing third molars was conducted. 3 examiners independently evaluated the radiographs and only those cases where at least 2 observers agreed were included in this report. Statistical analysis was performed on 186 radiographs. Associations were analyzed with the Pearson chi 2 test. Radiographic evidence of root resorption was found in 45 2nd molars (24.2%) of which 12 (6.5%) showed moderate to complete root resorption. Non-erupted tooth apical position and mesio-inclination of 60 degrees or more relative to the distal root of the second molar were significantly associated with root resorption (p = 0.01368 and p = 0.0194, respectively). Resorption was positively associated with age of patient (p = 0.00606). These results may support early extraction of impacted 3rd molars especially in cases with a mesio-angulation of 60 degrees or more and an apical location in proximity to the distal root of the 2nd molar. PMID:8891930
The Relationship between Personal Values and Attitude towards Teaching Profession
ERIC Educational Resources Information Center
Bektas, Fatih; Nalcaci, Ahmet
2012-01-01
This study aimed to determine to what extent the personal values of class teacher candidates predict their attitude towards teaching. The universe of the research is teacher candidates from the Kazim Karabekir Faculty of Education, Ankara University in the 2010-2011 academic year. 305 teacher candidates from 1st, 2nd, 3rd and 4th year class were…
Singular inflationary universe from F (R ) gravity
NASA Astrophysics Data System (ADS)
Odintsov, S. D.; Oikonomou, V. K.
2015-12-01
Unlike crushing singularities, the so-called type IV finite time singularity offers the possibility that the Universe passes smoothly it, without any catastrophic effects. Then the question is if the effects of a type IV singularity can be detected in the process of cosmic evolution. In this paper we address this question in the context of F (R ) gravity. As we demonstrate, the effects of a type IV singularity appear in the Hubble flow parameters, which determine the dynamical evolution of the cosmological system. So we study various inflation models incorporating a type IV singularity, with the singularity occurring at the end of inflation. Particularly we study a toy model and a singular version of the R2 gravity Hubble rate. As we evince, some of the Hubble flow parameters become singular at the singularity, an effect which indicates that at that point a dynamical instability occurs. This dynamical instability eventually indicates the graceful exit from inflation. We demonstrate that the toy model has an unstable de Sitter point at the singularity, so indeed graceful exit could be triggered. In the case of the singular inflation model, graceful exit proceeds in the standard way. In addition, we investigate how the form of the F (R ) gravity affects the singularity structure of the Hubble flow parameters. In the case of the singular inflation model, we found various scenarios for singular evolution, most of which are compatible with observations, and only one leads to severe instabilities. In addition, in one of these scenarios, the presence of the type IV singularity slightly modifies the spectral index of primordial curvature perturbations. We also compare the ordinary Starobinsky with the singular inflation model, and we point out the qualitative and quantitative differences. Finally, we study the late-time dynamics of the toy model and of the singular inflation model and we demonstrate that the unification of early and late-time acceleration can be achieved
The complex structured singular value
NASA Technical Reports Server (NTRS)
Packard, A.; Doyle, J.
1993-01-01
A tutorial introduction to the complex structured singular value (mu) is presented, with an emphasis on the mathematical aspects of mu. The mu-based methods discussed here have been useful for analyzing the performance and robustness properties of linear feedback systems. Several tests for robust stability and performance with computable bounds for transfer functions and their state space realizations are compared, and a simple synthesis problem is studied. Uncertain systems are represented using linear fractional transformations which naturally unify the frequency-domain and state space methods.
Dimensional Mutation and Spacelike Singularities
Silverstein, Eva; /SLAC /Stanford U., Phys. Dept.
2005-10-28
I argue that critical string theory on a Riemann surface of genus h >> 1 crosses over, when the surface approaches the string scale in size, to a background of supercritical string theory with effective central charge as large as 2h. Concrete evidence for this proposal is provided by the high energy density of states (realized on the Riemann surface side by strings wrapping nontrivial elements of the fundamental group) and by a linear sigma model which at large h approximates the time evolution through the initial transition. This suggests that cosmological singularities arising in negatively curved FRW backgrounds may be replaced by a phase of supercritical string theory.
String spectra near some null cosmological singularities
Madhu, Kallingalthodi; Narayan, K.
2009-06-15
We construct cosmological spacetimes with null Kasner-like singularities as purely gravitational solutions with no other background fields turned on. These can be recast as anisotropic plane-wave spacetimes by coordinate transformations. We analyze string quantization to find the spectrum of string modes in these backgrounds. The classical string modes can be solved for exactly in these time-dependent backgrounds, which enables a detailed study of the near-singularity string spectrum, (time-dependent) oscillator masses, and wave functions. We find that for low-lying string modes (finite oscillation number), the classical near-singularity string mode functions are nondivergent for various families of singularities. Furthermore, for any infinitesimal regularization of the vicinity of the singularity, we find a tower of string modes of ultrahigh oscillation number which propagate essentially freely in the background. The resulting picture suggests that string interactions are non-negligible near the singularity.
Large-scale sparse singular value computations
NASA Technical Reports Server (NTRS)
Berry, Michael W.
1992-01-01
Four numerical methods for computing the singular value decomposition (SVD) of large sparse matrices on a multiprocessor architecture are presented. Lanczos and subspace iteration-based methods for determining several of the largest singular triplets (singular values and corresponding left and right-singular vectors) for sparse matrices arising from two practical applications: information retrieval and seismic reflection tomography are emphasized. The target architectures for implementations are the CRAY-2S/4-128 and Alliant FX/80. The sparse SVD problem is well motivated by recent information-retrieval techniques in which dominant singular values and their corresponding singular vectors of large sparse term-document matrices are desired, and by nonlinear inverse problems from seismic tomography applications which require approximate pseudo-inverses of large sparse Jacobian matrices.
Multichannel framework for singular quantum mechanics
Camblong, Horacio E.; Epele, Luis N.; Fanchiotti, Huner; García Canal, Carlos A.; Ordóñez, Carlos R.
2014-01-15
A multichannel S-matrix framework for singular quantum mechanics (SQM) subsumes the renormalization and self-adjoint extension methods and resolves its boundary-condition ambiguities. In addition to the standard channel accessible to a distant (“asymptotic”) observer, one supplementary channel opens up at each coordinate singularity, where local outgoing and ingoing singularity waves coexist. The channels are linked by a fully unitary S-matrix, which governs all possible scenarios, including cases with an apparent nonunitary behavior as viewed from asymptotic distances. -- Highlights: •A multichannel framework is proposed for singular quantum mechanics and analogues. •The framework unifies several established approaches for singular potentials. •Singular points are treated as new scattering channels. •Nonunitary asymptotic behavior is subsumed in a unitary multichannel S-matrix. •Conformal quantum mechanics and the inverse quartic potential are highlighted.
Precursory singularities in spherical gravitational collapse
NASA Astrophysics Data System (ADS)
Lake, Kayll
1992-05-01
General conditions are developed for the formation of naked precursory ('shell-focusing') singularities in spherical gravitational collapse. These singularities owe their nakedness to the fact that the gravitational potential fails to be single valued prior to the onset of a true gravitational singularity. It is argued that they do not violate the spirit of cosmic censorship. Rather, they may well be an essentially generic feature of relativistic gravitational collapse.
Exact solutions and singularities in string theory
Horowitz, G.T. ); Tseytlin, A.A. )
1994-10-15
We construct two new classes of exact solutions to string theory which are not of the standard plane wave of gauged WZW type. Many of these solutions have curvature singularities. The first class includes the fundamental string solution, for which the string coupling vanishes near the singularity. This suggests that the singularity may not be removed by quantum corrections. The second class consists of hybrids of plane wave and gauged WZW solutions. We discuss a four-dimensional example in detail.
Understanding singularities — Classical and quantum
NASA Astrophysics Data System (ADS)
Konkowski, Deborah A.; Helliwell, Thomas M.
2016-01-01
The definitions of classical and quantum singularities are reviewed. Examples are given of both as well as their utility in general relativity. In particular, the classical and quantum singularity structure of certain interesting conformally static spherically symmetric spacetimes modeling scalar field collapse are reviewed. The spacetimes include the Roberts spacetime, the Husain-Martinez-Nuñez spacetime and the Fonarev spacetime. The importance of understanding spacetime singularity structure is discussed.
Quantum dress for a naked singularity
NASA Astrophysics Data System (ADS)
Casals, Marc; Fabbri, Alessandro; Martínez, Cristián; Zanelli, Jorge
2016-09-01
We investigate semiclassical backreaction on a conical naked singularity space-time with a negative cosmological constant in (2 + 1)-dimensions. In particular, we calculate the renormalized quantum stress-energy tensor for a conformally coupled scalar field on such naked singularity space-time. We then obtain the backreacted metric via the semiclassical Einstein equations. We show that, in the regime where the semiclassical approximation can be trusted, backreaction dresses the naked singularity with an event horizon, thus enforcing (weak) cosmic censorship.
Naked singularities and quantum gravity
Harada, Tomohiro; Iguchi, Hideo; Nakao, Ken-ichi; Singh, T. P.; Tanaka, Takahiro; Vaz, Cenalo
2001-08-15
There are known models of spherical gravitational collapse in which the collapse ends in a naked shell-focusing singularity for some initial data. If a massless scalar field is quantized on the classical background provided by such a star, it is found that the outgoing quantum flux of the scalar field diverges in the approach to the Cauchy horizon. We argue that the semiclassical approximation (i.e., quantum field theory on a classical curved background) used in these analyses ceases to be valid about one Planck time before the epoch of naked singularity formation, because by then the curvature in the central region of the star reaches the Planck scale. It is shown that during the epoch in which the semiclassical approximation is valid, the total emitted energy is about one Planck unit, and is not divergent. We also argue that back reaction in this model does not become important so long as gravity can be treated classically. It follows that the further evolution of the star will be determined by quantum gravitational effects, and without invoking quantum gravity it is not possible to say whether the star radiates away on a short time scale or settles down into a black hole state.
Compact submanifolds supporting singular interactions
Kaynak, Burak Tevfik Teoman Turgut, O.
2013-12-15
A quantum particle moving under the influence of singular interactions on embedded surfaces furnish an interesting example from the spectral point of view. In these problems, the possible occurrence of a bound-state is perhaps the most important aspect. Such systems can be introduced as quadratic forms and generically they do not require renormalization. Yet an alternative path through the resolvent is also beneficial to study various properties. In the present work, we address these issues for compact surfaces embedded in a class of ambient manifolds. We discover that there is an exact bound state solution written in terms of the heat kernel of the ambient manifold for a range of coupling strengths. Moreover, we develop techniques to estimate bounds on the ground state energy when several surfaces, each of which admits a bound state solution, coexist. -- Highlights: •Schrödinger operator with singular interactions supported on compact submanifolds. •Exact bound-state solution in terms of the heat kernel of the ambient manifold. •Generalization of the variational approach to a collection of submanifolds. •Existence of a lower bound for a unique ground state energy.
Box graphs and singular fibers
NASA Astrophysics Data System (ADS)
Hayashi, Hirotaka; Lawrie, Craig; Morrison, David R.; Schafer-Nameki, Sakura
2014-05-01
We determine the higher codimension fibers of elliptically fibered Calabi-Yau fourfolds with section by studying the three-dimensional = 2 supersymmetric gauge theory with matter which describes the low energy effective theory of M-theory compactified on the associated Weierstrass model, a singular model of the fourfold. Each phase of the Coulomb branch of this theory corresponds to a particular resolution of the Weierstrass model, and we show that these have a concise description in terms of decorated box graphs based on the representation graph of the matter multiplets, or alternatively by a class of convex paths on said graph. Transitions between phases have a simple interpretation as "flopping" of the path, and in the geometry correspond to actual flop transitions. This description of the phases enables us to enumerate and determine the entire network between them, with various matter representations for all reductive Lie groups. Furthermore, we observe that each network of phases carries the structure of a (quasi-)minuscule representation of a specific Lie algebra. Interpreted from a geometric point of view, this analysis determines the generators of the cone of effective curves as well as the network of flop transitions between crepant resolutions of singular elliptic Calabi-Yau fourfolds. From the box graphs we determine all fiber types in codimensions two and three, and we find new, non-Kodaira, fiber types for E 6, E7 and E 8.
Cserni, Gábor; Kulka, Janina; Francz, Monika; Járay, Balázs; Kálmán, Endre; Kovács, Ilona; Krenács, Tibor; Udvarhelyi, Nóra; Vass, László
2016-09-01
There have been relevant changes in the diagnosis and treatment of breast cancer to implement the updating of the 2010 recommendations made during the 2nd national consensus conference on the disease. Following a wide interdisciplinary consultation, the present recommendations have been finalized after their public discussion at the 3rd Hungarian Consensus Conference on Breast Cancer. The recommendations cover non-operative and intraoperative diagnostics, the work-up of operative specimens, the determination of prognostic and predictive markers and the content of the cytology and histology reports. Furthermore, it touches some special issues such as the current status of multigene molecular markers, the role of pathologists in clinical trials and prerequisites for their involvement, some relevant points about the future. PMID:27579721
Abbott, Richard W; Gordon, Ben; van Amsterdam, Peter; Lausecker, Berthold; Brudny-Kloeppel, Margarete; Smeraglia, John; Romero, Fernando; Globig, Susanne; Golob, Michaela; Knutsson, Magnus; Herling, Christian; Vieser, Eva; Timmerman, Philip
2011-04-01
The European Bioanalysis Forum is a bioanalytical nonprofit organization comprised of European pharmaceutical companies (27 members to date) and currently expanding to include CROs as well. The European Bioanalysis Forum provides a broad European bioanalytical network for the discussion of scientific, technological and regulatory topics of bioanalytical interest. The 3rd Annual Open Symposium was again much anticipated after the two previous successful meetings. The symposium included sessions on thinking outside the 'commodity' box, bioanalytical challenges with blood, global harmonization, assay platforms, dried blood spots, immunogenicity, matrix effects, anomalous results, biomarkers and two plenary technology sessions hosted by the Platinum sponsors. Experts and key opinion leaders were invited as guest speakers. A total of 424 delegates registered from 113 companies representing a large percentage of the European bioanalytical community. In addition to 48 oral presentations, 88 posters were presented and there was a vendor exposition of 40 companies.
Tarkowski, Radoslaw; Vetto, John T
2015-09-01
Technical skills are not sufficient for successful surgical care. Non-technical skills such as team work, decision-making in cancer treatment, communication with the patient, ethical challenges, situation awareness, and communication in the operating room are mandatory for favorable outcomes. Although formally taught in other high-demand disciplines, such skills were traditionally rarely discussed in surgical oncology. The 3rd MAYMET-ESO Joint Meeting "Professionalism for Breast Surgeons" held in Istanbul, Turkey, 5 October 2013 was dedicated to the development of non-technical skills in the everyday activity of breast surgeons. We briefly discuss information from this very interesting and inspiring educational event and how it relates to more recent changes in surgical oncology education. PMID:25903052
NASA Astrophysics Data System (ADS)
Gassner, T.; Schoepf, K.; Sharapov, S. E.; Kiptily, V. G.; Pinches, S. D.; Hellesen, C.; Eriksson, J.; JET-EFDA contributors
2012-03-01
Experiments on accelerating NBI-produced deuterium (D) beam ions from their injection energy of ˜110 keV up to the MeV energy range with 3rd harmonic ion cyclotron resonance heating were performed on the Joint European Torus [P. H. Rebut and B. E. Keen, Fusion Technol. 11, 13 (1987)]. A renewed set of nuclear diagnostics was used for analysing fast D ions during sawtooth stabilization, monster sawtooth crashes, and during excitation of Alfvén eigenmodes (AEs) residing inside the q = 1 radius. The measurements and modeling of the fast ions with the nonlinear HAGIS code [S. D. Pinches et al., Comput. Phys. Commun. 111, 133 (1998)] show that monster sawtooth crashes are strongly facilitated by the AE-induced re-distribution of the fast D ions from inside the q = 1 radius to the plasma edge.
NASA Astrophysics Data System (ADS)
Akhtar-Schuster, Mariam; Safriel, Uriel; Abraham, Elena; de Vente, Joris; Essahli, Wafa; Escadafal, Richard; Stringer, Lindsay
2015-04-01
Achieving land degradation neutrality (LDN) through sustainable land management (SLM) targets the maintenance or restoration of the productivity of land, and therefore has to include decision-makers, knowledge generators and knowledge holders at the different relevant geographic scales. In order to enhance the implementation of the Convention, the Conference of the Parties (COP) of the United Nations Convention to Combat Desertification therefore decided that each future session of its Committee on Science and Technology (CST) would be organized in a predominantly scientific and technical conference-style format. This contribution will outline the major outcomes of UNCCD's 3rd scientific conference that will be held in Cancún, Mexico, from 9 to 12 March 2015, on addressing desertification, land degradation and drought issues (DLDD) for poverty reduction and sustainable development. The conference follows an exceptional new round table conference format that will allow the various stakeholders to discuss scientific as well as the contribution of traditional knowledge and practices in combating land degradation. This format should provide two-way communication and enable deeper insight into the availability and contribution of all forms of knowledge for achieving LDN through the assessment of: • the vulnerability of lands to DLDD and climate change and the adaptive capacities of socio-ecosystems; • best examples of adapted, knowledge-based practices and technologies; • monitoring and assessment methods to evaluate the effectiveness of adaptation practices and technologies. The outcomes of UNCCD's 3rd scientific conference will serve as a basis for discussing: • contributions of science to diagnose the status of land; • research gaps that need to be addressed to achieve LDN for poverty reduction; • additional institutional requirements to optimally bridge knowledge generation, knowledge maintenance and knowledge implementation at the science
Deal, Alex L.; Erickson, Kristen J.; Shiers, Stephanie I.; Burman, Michael A.
2016-01-01
Classical fear conditioning creates an association between an aversive stimulus and a neutral stimulus. Although the requisite neural circuitry is well understood in mature organisms, the development of these circuits is less well studied. The current experiments examine the ontogeny of fear conditioning and relate it to neuronal activation assessed through immediate early gene (IEG) expression in the amygdala, hippocampus, perirhinal cortex, and hypothalamus of periweanling rats. Rat pups were fear conditioned, or not, during the 3rd or 4th weeks of life. Neuronal activation was assessed by quantifying expression of FBJ osteosarcoma oncogene (FOS) using immunohistochemistry (IHC) in Experiment 1. Fos and early growth response gene-1 (EGR1) expression was assessed using qRT-PCR in Experiment 2. Behavioral data confirm that both auditory and contextual fear continue to emerge between PD 17 and 24. The IEG expression data are highly consistent with these behavioral results. IHC results demonstrate significantly more FOS protein expression in the basal amygdala of fear conditioned PD 23 subjects compared to control subjects, but no significant difference at PD 17. qRT-PCR results suggest specific activation of the amygdala only in older subjects during auditory fear expression. A similar effect of age and conditioning status was also observed in the perirhinal cortex during both contextual and auditory fear expression. Overall, the development of fear conditioning occurring between the 3rd and 4th weeks of life appears to be at least partly attributable to changes in activation of the amygdala and perirhinal cortex during fear conditioning or expression. PMID:26820587
Patel, Vikram; Chisholm, Dan; Parikh, Rachana; Charlson, Fiona J; Degenhardt, Louisa; Dua, Tarun; Ferrari, Alize J; Hyman, Steve; Laxminarayan, Ramanan; Levin, Carol; Lund, Crick; Medina Mora, María Elena; Petersen, Inge; Scott, James; Shidhaye, Rahul; Vijayakumar, Lakshmi; Thornicroft, Graham; Whiteford, Harvey
2016-04-16
The burden of mental, neurological, and substance use (MNS) disorders increased by 41% between 1990 and 2010 and now accounts for one in every 10 lost years of health globally. This sobering statistic does not take into account the substantial excess mortality associated with these disorders or the social and economic consequences of MNS disorders on affected persons, their caregivers, and society. A wide variety of effective interventions, including drugs, psychological treatments, and social interventions, can prevent and treat MNS disorders. At the population-level platform of service delivery, best practices include legislative measures to restrict access to means of self-harm or suicide and to reduce the availability of and demand for alcohol. At the community-level platform, best practices include life-skills training in schools to build social and emotional competencies. At the health-care-level platform, we identify three delivery channels. Two of these delivery channels are especially relevant from a public health perspective: self-management (eg, web-based psychological therapy for depression and anxiety disorders) and primary care and community outreach (eg, non-specialist health worker delivering psychological and pharmacological management of selected disorders). The third delivery channel, hospital care, which includes specialist services for MNS disorders and first-level hospitals providing other types of services (such as general medicine, HIV, or paediatric care), play an important part for a smaller proportion of cases with severe, refractory, or emergency presentations and for the integration of mental health care in other health-care channels, respectively. The costs of providing a significantly scaled up package of specified cost-effective interventions for prioritised MNS disorders in low-income and lower-middle-income countries is estimated at US$3-4 per head of population per year. Since a substantial proportion of MNS disorders run a
Patel, Vikram; Chisholm, Dan; Parikh, Rachana; Charlson, Fiona J; Degenhardt, Louisa; Dua, Tarun; Ferrari, Alize J; Hyman, Steve; Laxminarayan, Ramanan; Levin, Carol; Lund, Crick; Medina Mora, María Elena; Petersen, Inge; Scott, James; Shidhaye, Rahul; Vijayakumar, Lakshmi; Thornicroft, Graham; Whiteford, Harvey
2016-04-16
The burden of mental, neurological, and substance use (MNS) disorders increased by 41% between 1990 and 2010 and now accounts for one in every 10 lost years of health globally. This sobering statistic does not take into account the substantial excess mortality associated with these disorders or the social and economic consequences of MNS disorders on affected persons, their caregivers, and society. A wide variety of effective interventions, including drugs, psychological treatments, and social interventions, can prevent and treat MNS disorders. At the population-level platform of service delivery, best practices include legislative measures to restrict access to means of self-harm or suicide and to reduce the availability of and demand for alcohol. At the community-level platform, best practices include life-skills training in schools to build social and emotional competencies. At the health-care-level platform, we identify three delivery channels. Two of these delivery channels are especially relevant from a public health perspective: self-management (eg, web-based psychological therapy for depression and anxiety disorders) and primary care and community outreach (eg, non-specialist health worker delivering psychological and pharmacological management of selected disorders). The third delivery channel, hospital care, which includes specialist services for MNS disorders and first-level hospitals providing other types of services (such as general medicine, HIV, or paediatric care), play an important part for a smaller proportion of cases with severe, refractory, or emergency presentations and for the integration of mental health care in other health-care channels, respectively. The costs of providing a significantly scaled up package of specified cost-effective interventions for prioritised MNS disorders in low-income and lower-middle-income countries is estimated at US$3-4 per head of population per year. Since a substantial proportion of MNS disorders run a
Ramond singular vectors and Jack superpolynomials
NASA Astrophysics Data System (ADS)
Alarie-Vézina, Ludovic; Desrosiers, Patrick; Mathieu, Pierre
2014-01-01
The explicit formula for the superconformal singular vectors in the Neveu-Schwarz sector has been obtained recently, via its symmetric polynomial representation, as a sum of Jack superpolynomials. Here we present the analogous, but slightly more complicated, closed-form expression for the Ramond singular vectors.
Varying constant cosmologies and cosmic singularities
NASA Astrophysics Data System (ADS)
Dabrowski, Mariusz P.; Marosek, Konrad
2013-02-01
We review standard and non-standard cosmological singularities paying special attention onto those which are of a weak type and do not necessarily exhibit geodesic incompletness. Then, we discuss how these singularities can be weakened, strengthened, or avoided due to the time-variation of the physical constants such as the speed of light c and the gravitational constant G.
NASA Astrophysics Data System (ADS)
Tsalamengas, John L.
2015-12-01
We present n-point Gauss-Gegenbauer quadrature rules for weakly singular, strongly singular, and hypersingular integrals that arise in integral equation formulations of potential problems in domains with edges and corners. The rules are tailored to weight functions with algebraic endpoint singularities related to the geometrical singularities of the domain. Each rule has two different expressions involving Legendre functions and hypergeometric functions, respectively. Numerical examples amply demonstrate the accuracy and stability of the proposed algorithms. Application to the solution of a singular integral equation is exemplified.
Naked shell singularities on the brane
Seahra, Sanjeev S.
2005-04-15
By utilizing nonstandard slicings of 5-dimensional Schwarzschild and Schwarzschild-AdS manifolds based on isotropic coordinates, we generate static and spherically-symmetric braneworld spacetimes containing shell-like naked null singularities. For planar slicings, we find that the brane-matter sourcing the solution is a perfect fluid with an exotic equation of state and a pressure singularity where the brane crosses the bulk horizon. From a relativistic point of view, such a singularity is required to maintain matter infinitesimally above the surface of a black hole. From the point of view of the AdS/CFT conjecture, the singular horizon can be seen as one possible quantum correction to a classical black hole geometry. Various generalizations of planar slicings are also considered for a Ricci-flat bulk, and we find that singular horizons and exotic matter distributions are common features.
Singular perturbations and the sounding rocket problem
NASA Technical Reports Server (NTRS)
Ardema, M. D.
1979-01-01
In this paper, Goddard's problem of maximizing the final altitude of a sounding rocket (a singular problem of optimal control) is analyzed using singular perturbation methods. The problem is first cast in singular perturbation form and then solved to zero order by adding boundary-layer corrections to the reduced solution. For a quadratic drag law, a closed-form solution is obtained, although consideration of a numerical example indicates that this solution is not useful for practical sounding rockets. However, use of state variable transformations allows a very accurate numerical approximation to be constructed. It is concluded that application of singular perturbation methods to the well-known sounding rocket problem indicates that these methods may have utility in dealing with singular problems of optimal control.
NASA Technical Reports Server (NTRS)
Sidi, A.; Israeli, M.
1986-01-01
High accuracy numerical quadrature methods for integrals of singular periodic functions are proposed. These methods are based on the appropriate Euler-Maclaurin expansions of trapezoidal rule approximations and their extrapolations. They are used to obtain accurate quadrature methods for the solution of singular and weakly singular Fredholm integral equations. Such periodic equations are used in the solution of planar elliptic boundary value problems, elasticity, potential theory, conformal mapping, boundary element methods, free surface flows, etc. The use of the quadrature methods is demonstrated with numerical examples.
NASA Astrophysics Data System (ADS)
Wershow, H. N.; Green, M.; Stocker, A.; Staires, D.
2010-12-01
Current efforts towards Earth Science literacy in New Mexico are guided by the New Mexico Science Benchmarks [1]. We are geoscience professionals in Los Alamos, NM who believe there is an important role for non-traditional educators utilizing innovative teaching methods. We propose to further Earth Science literacy for local 3rd and 4th grade students using a kinesthetic learning approach, with the goal of fostering an interactive relationship between the students and their geologic environment. We will be working in partnership with the Pajarito Environmental Education Center (PEEC), which teaches the natural heritage of the Pajarito Plateau to 3rd and 4th grade students from the surrounding area, as well as the Family YMCA’s Adventure Programs Director. The Pajarito Plateau provides a remarkable geologic classroom because minimal structural features complicate the stratigraphy and dramatic volcanic and erosional processes are plainly on display and easily accessible. Our methodology consists of two approaches. First, we will build an interpretive display of the local geology at PEEC that will highlight prominent rock formations and geologic processes seen on a daily basis. It will include a simplified stratigraphic section with field specimens and a map linked to each specimen’s location to encourage further exploration. Second, we will develop and implement a kinesthetic curriculum for an exploratory field class. Active engagement with geologic phenomena will take place in many forms, such as a scavenger hunt for precipitated crystals in the vesicles of basalt flows and a search for progressively smaller rhyodacite clasts scattered along an actively eroding canyon. We believe students will be more receptive to origin explanations when they possess a piece of the story. Students will be provided with field books to make drawings of geologic features. This will encourage independent assessment of phenomena and introduce the skill of scientific observation. We
Veterinary Microbiology, 3rd Edition
Technology Transfer Automated Retrieval System (TEKTRAN)
Veterinary Microbiology, Third Edition is organized into four sections and begins with an updated and expanded introductory section on infectious disease pathogenesis, diagnosis and clinical management. The second section covers bacterial and fungal pathogens, and the third section describes viral d...
Generalizations of the abstract boundary singularity theorem
NASA Astrophysics Data System (ADS)
Whale, Ben E.; Ashley, Michael J. S. L.; Scott, Susan M.
2015-07-01
The abstract boundary singularity theorem was first proven by Ashley and Scott. It links the existence of incomplete causal geodesics in strongly causal, maximally extended spacetimes to the existence of abstract boundary essential singularities, i.e., non-removable singular boundary points. We give two generalizations of this theorem: the first to continuous causal curves and the distinguishing condition, the second to locally Lipschitz curves in manifolds such that no inextendible locally Lipschitz curve is totally imprisoned. To do this we extend generalized affine parameters from C1 curves to locally Lipschitz curves.
Singular plastic element: NASTRAN implementation and application
NASA Technical Reports Server (NTRS)
Hussain, M. A.; Pu, S. L.; Lorensen, W. E.
1977-01-01
The elastic and plastic singularities near a crack tip are obtained from higher order isoparametric elements. This is simply accomplished by collapsing the quadrilateral element into the triangular element and by judicious choice of adjacent mid-side nodes. Specifically for the cubic element the elastic singularity is obtained by placing the mid-side nodes adjacent to the crack tip at 1/9th and 4/9th locations. The plastic singularity is constructed using the sliding node concept. These elements have been implemented in NASTRAN as user dummy elements.
Multichannel framework for singular quantum mechanics
NASA Astrophysics Data System (ADS)
Camblong, Horacio E.; Epele, Luis N.; Fanchiotti, Huner; García Canal, Carlos A.; Ordóñez, Carlos R.
2014-01-01
A multichannel S-matrix framework for singular quantum mechanics (SQM) subsumes the renormalization and self-adjoint extension methods and resolves its boundary-condition ambiguities. In addition to the standard channel accessible to a distant ("asymptotic") observer, one supplementary channel opens up at each coordinate singularity, where local outgoing and ingoing singularity waves coexist. The channels are linked by a fully unitary S-matrix, which governs all possible scenarios, including cases with an apparent nonunitary behavior as viewed from asymptotic distances.
First Person Singular: Building the Road as We Travel
ERIC Educational Resources Information Center
Long, Michael H.
2015-01-01
After completing a law degree at the University of Birmingham when I was 20 and not really knowing what I wanted to do, except that it was not law, I became an English as a foreign language (EFL) teacher accidentally through signing up as a volunteer with the British United Nations Association (BUNA), roughly equivalent to the US Peace Corps.…
Lösch, Sandra; Moghaddam, Negahnaz; Grossschmidt, Karl; Risser, Daniele U.; Kanz, Fabian
2014-01-01
The gladiator cemetery discovered in Ephesus (Turkey) in 1993 dates to the 2nd and 3rd century AD. The aim of this study is to reconstruct diverse diet, social stratification, and migration of the inhabitants of Roman Ephesus and the distinct group of gladiators. Stable carbon, nitrogen, and sulphur isotope analysis were applied, and inorganic bone elements (strontium, calcium) were determined. In total, 53 individuals, including 22 gladiators, were analysed. All individuals consumed C3 plants like wheat and barley as staple food. A few individuals show indication of consumption of C4 plants. The δ13C values of one female from the gladiator cemetery and one gladiator differ from all other individuals. Their δ34S values indicate that they probably migrated from another geographical region or consumed different foods. The δ15N values are relatively low in comparison to other sites from Roman times. A probable cause for the depletion of 15N in Ephesus could be the frequent consumption of legumes. The Sr/Ca-ratios of the gladiators were significantly higher than the values of the contemporary Roman inhabitants. Since the Sr/Ca-ratio reflects the main Ca-supplier in the diet, the elevated values of the gladiators might suggest a frequent use of a plant ash beverage, as mentioned in ancient texts. PMID:25333366
NASA Technical Reports Server (NTRS)
Schmid, B; Eilers, J. A.; McIntosh, D. M.; Longo, K.; Livingston, J. M.; Redemann, J.; Russell, P. B.; Braun, J.; Rocken, C.; Hipskind, R. Stephen (Technical Monitor)
2001-01-01
We conducted ground-based measurements with the Ames Airborne Tracking 6-channel Sunphotometer (AATS-6) during the 3rd Water Vapor IOP (WVIOP3), September 18 - October 8, 2000 at the SGP ARM site. For this deployment our primary result was columnar water vapor (CWV) obtained from continuous solar transmittance measurements in the 0.94-micron band. In addition, we simultaneously measured aerosol optical depth (AOD) at 380, 450, 525, 864 and 1020 nm. During the IOP, preliminary results of CWV and AOD were displayed in real-time. The result files were made available to other investigators by noon of the next day. During WVIOP3 those data were shown on the daily intercomparison plots on the IOP web-site. Our preliminary results for CWV fell within the spread of values obtained from other techniques. After conclusion of WVIOP3, AATS-6 was shipped directly to Mauna Loa, Hawaii for post-mission calibration. The updated calibration, a cloud screening technique for AOD, along with other mostly cosmetic changes were applied to the WVIOP3 data set and released as version 0.1. The resulting changes in CWV are small, the changes in AOD and Angstrom parameter are more noticeable. Data version 0.1 was successfully submitted to the ARM External Data Center. In the poster we will show data examples for both CWV and AOD. We will also compare our CWV results with those obtained from a GPS (Global Positioning System) slant path method.
NASA Astrophysics Data System (ADS)
Russo Ermolli, Elda; Romano, Paola; Liuzza, Viviana; Amato, Vincenzo; Ruello, Maria Rosaria; Di Donato, Valentino
2014-05-01
Campania has always offered suitable climatic and physiographic conditions for human settlements since prehistoric times. In particular, many Graeco-Roman towns developed along its coasts starting from the 7th-6th cent. BC. In the last decade, geoarchaelogical surveys have been carried out in the archaeological excavations of Neapolis, Paestum and Elea-Velia allowing the main steps of the landscape evolution around these towns to be defined in detail. The greek town of Neapolis rose in the late 6th cent. BC [1] on a terrace overlooking a low-relief rocky coast surrounded by volcanic hills. Port activities developed in a protected bay facing the town from the 4th-2nd cent. BC up to the 4th cent. AD, as testified by the discovery of structures and shipwrecks [2, 3, 4]. Starting from the 3rd cent. AD a spit bar formed at the bay entrance causing the progressive establishment of a lagoon which was gradually filled up by alluvial inputs and completely closed in the 5th cent. AD. During the same period, episodes of increased alluvial inputs were also recorded further west along the coast, where a narrow sandy beach formed at the cliff toe. The greek town of Poseidonia, renamed Paestum by the Romans, was founded in the 540 BC on a travertine terrace facing the sandy littoral of a prograding coastal plain [5]. In front of the main town door, a coastal lagoon developed thanks to the growth of a dune ridge and was probably used for harbor activities [5]. After this period the shoreline shifted seawards, another dune ridge formed and the back-ridge depression was filled with fluvial-marshy deposits, slowly drying up. Phases of travertine deposition, which characterized the SE sector of the plain all along the Holocene, were recorded in the northern and southern quarters of the town in historical times and were connected to the abandonment of the town in the early Medieval times. The greek colony of Elea-Velia was located on top of a siliciclastic promontory where the ruins of
Kua, J.; Goddard, W.A. III
1999-12-01
Using first principles quantum mechanics [nonlocal density functional theory (B3LYP)], the authors calculated the 13 most likely intermediate species for methanol oxidation on clusters of all 2nd and 3rd row Group VIII transition metals for all three likely binding sites (top, bridge, and cap). This comprehensive set of binding energies and structures allows a detailed analysis of possible reaction mechanisms and how they change for different metals. This illustrates the role in which modern quantum chemical methods can be used to provide data for combinatorial strategies for discovering and designing new catalysts. Methanol dehydrogenation is most facile on Pt, with the hydrogens preferentially stripped off the carbon end. However, water dehydrogenation is most facile on Ru. These results support the bifunctional mechanism for methanol oxidation on Pt-Ru alloys in direct methanol fuel cells (DMFCs). Pure Os is capable of performing both functionalities without cocatalyst. It is suggested that pure Os be examined as a potential catalyst for low overpotential, highly dispersed catalyst DMFCs. Pathways to form the second C-O bond differ between the pure metals (Pt and Os) in which (CO){sub ads} is probably activated by (OH){sub ads} and the Pt-Ru binary system in which (COH){sub ads} is probably activated by O{sub ads}. For all cases formation of (COOH){sub ads} is an important precursor to the final dehydrogenation to desorb CO{sub 2} from the surface.
Petzold, Christopher; Keasling, Jay
2011-07-18
This document is Chapter 25 in the Manual of Industrial Microbiology and Biotechnology, 3rd edition. Topics covered include: Incorporation of Amorpha-4,11-Diene Biosynthetic Pathway into E. coli; Amorpha-4,11-Diene Pathway Optimization; "-Omics" Analyses for Increased Amorpha-4,11-Diene Production; Biosynthetic Oxidation of Amorpha-4,11-Diene.
Gravitational radiation from a cylindrical naked singularity
Nakao, Ken-ichi; Morisawa, Yoshiyuki
2005-06-15
We construct an approximate solution which describes the gravitational emission from a naked singularity formed by the gravitational collapse of a cylindrical thick shell composed of dust. The assumed situation is that the collapsing speed of the dust is very large. In this situation, the metric variables are obtained approximately by a kind of linear perturbation analysis in the background Morgan solution which describes the motion of cylindrical null dust. The most important problem in this study is what boundary conditions for metric and matter variables should be imposed at the naked singularity. We find a boundary condition that all the metric and matter variables are everywhere finite at least up to the first order approximation. This implies that the spacetime singularity formed by this high-speed dust collapse is very similar to that formed by the null dust and the final singularity will be a conical one. Weyl curvature is completely released from the collapsed dust.
Quantum singularities in the BTZ spacetime
Pitelli, Joao Paulo M.; Letelier, Patricio S.
2008-06-15
The spinless Banados-Teiltelboim-Zanelli spacetime is considered in the quantum theory context. Specifically, we study the case of a negative mass parameter using quantum test particles obeying the Klein-Gordon and Dirac equations. We study if this classical singular spacetime, with a naked singularity at the origin, remains singular when tested with quantum particles. The need for additional information near the origin is confirmed for massive scalar particles and all of the possible boundary conditions necessary to turn the spatial portion of the wave operator self-adjoint are found. When tested by massless scalar particles or fermions, the singularity is ''healed'' and no extra boundary condition is needed. Near infinity, no boundary conditions are necessary.
Constraints on singular evolution from gravitational baryogenesis
NASA Astrophysics Data System (ADS)
Oikonomou, V. K.
2016-02-01
We investigate how the gravitational baryogenesis mechanism can potentially constrain the form of a Type IV singularity. Specifically, we study two different models with interesting phenomenology, that realize two distinct Type IV singularities, one occurring at the end of inflation and one during the radiation domination era or during the matter domination era. As we demonstrate, the Type IV singularities occurring at the matter domination era or during the radiation domination era are constrained by the gravitational baryogenesis, in such a way so that these do not render the baryon to entropy ratio singular. Both the cosmological models we study cannot be realized in the context of ordinary Einstein-Hilbert gravity, and hence our work can only be realized in the context of F(R) gravity and more generally in the context of modified gravity only.
Stable computation of generalized singular values
Drmac, Z.; Jessup, E.R.
1996-12-31
We study floating-point computation of the generalized singular value decomposition (GSVD) of a general matrix pair (A, B), where A and B are real matrices with the same numbers of columns. The GSVD is a powerful analytical and computational tool. For instance, the GSVD is an implicit way to solve the generalized symmetric eigenvalue problem Kx = {lambda}Mx, where K = A{sup {tau}}A and M = B{sup {tau}}B. Our goal is to develop stable numerical algorithms for the GSVD that are capable of computing the singular value approximations with the high relative accuracy that the perturbation theory says is possible. We assume that the singular values are well-determined by the data, i.e., that small relative perturbations {delta}A and {delta}B (pointwise rounding errors, for example) cause in each singular value {sigma} of (A, B) only a small relative perturbation {vert_bar}{delta}{sigma}{vert_bar}/{sigma}.
Singular control in minimum time spacecraft reorientation
NASA Technical Reports Server (NTRS)
Seywald, Hans; Kumar, Renjith R.
1991-01-01
Spacecraft reorientation is investigated numerically for an inertially symmetric rigid spacecraft with three bounded independent control torques aligned with the principal axes. The dynamical system of the spacecraft and the framework of the optimal-control problem are established in order to identify all of the potential strategies. The investigation lists bang-bang solutions and finite-order and infinite-order singular arcs, and the conditions for the finite-order singular arcs are given. Numerical examples are developed for all of the control-logic systems, and the suboptimality of the rest-to-rest maneuvers is proven for principal-axis rotations. The most efficient control technique is the singular control of infinite order, and the vector-valued singular control can be utilized in a derivative of the switching function.
Singularity avoidance and time in quantum gravity
Kreienbuehl, Andreas
2009-06-15
We consider the quantization of a Friedmann-Robertson-Walker universe. We derive a reduced square root Hamiltonian by choosing the scale factor as time variable and quantize the theory using Pauli matrices a la Dirac. From the resulting spinor equation we show that there is no semiclassical wave packet that avoids the big bang singularity. Our work raises the question concerning the relationship between the choice of time and singularity avoidance.
Cosmological tests of sudden future singularities
NASA Astrophysics Data System (ADS)
Denkiewicz, Tomasz; Dąbrowski, Mariusz P.; Ghodsi, Hoda; Hendry, Martin A.
2012-04-01
We discuss combined constraints, coming from the cosmic microwave background shift parameter R, the baryon acoustic oscillations distance parameter A, and from the latest type Ia supernovae data, imposed on cosmological models which allow sudden future singularities of pressure. We show that due to their weakness such sudden singularities may happen in the very near future and that at present they can mimic standard dark energy models.
Dynamic Singularity Spectrum Distribution of Sea Clutter
NASA Astrophysics Data System (ADS)
Xiong, Gang; Yu, Wenxian; Zhang, Shuning
2015-12-01
The fractal and multifractal theory have provided new approaches for radar signal processing and target-detecting under the background of ocean. However, the related research mainly focuses on fractal dimension or multifractal spectrum (MFS) of sea clutter. In this paper, a new dynamic singularity analysis method of sea clutter using MFS distribution is developed, based on moving detrending analysis (DMA-MFSD). Theoretically, we introduce the time information by using cyclic auto-correlation of sea clutter. For transient correlation series, the instantaneous singularity spectrum based on multifractal detrending moving analysis (MF-DMA) algorithm is calculated, and the dynamic singularity spectrum distribution of sea clutter is acquired. In addition, we analyze the time-varying singularity exponent ranges and maximum position function in DMA-MFSD of sea clutter. For the real sea clutter data, we analyze the dynamic singularity spectrum distribution of real sea clutter in level III sea state, and conclude that the radar sea clutter has the non-stationary and time-varying scale characteristic and represents the time-varying singularity spectrum distribution based on the proposed DMA-MFSD method. The DMA-MFSD will also provide reference for nonlinear dynamics and multifractal signal processing.
Weyl anomaly and initial singularity crossing
NASA Astrophysics Data System (ADS)
Awad, Adel
2016-04-01
We consider the role of quantum effects, mainly, Weyl anomaly in modifying Friedmann-Lemaitre-Robertson-Walker (FLRW) model singular behavior at early times. Weyl anomaly corrections to FLRW models have been considered in the past, here we reconsider this model and show the following: The singularity of this model is weak according to Tipler and Krolak, therefore, the spacetime might admit a geodesic extension. Weyl anomaly corrections change the nature of the initial singularity from a big bang singularity to a sudden singularity. The two branches of solutions consistent with the semiclassical treatment form a disconnected manifold. Joining these two parts at the singularity provides us with a C1 extension to nonspacelike geodesics and leaves the spacetime geodesically complete. Using Gauss-Codazzi equations one can derive generalized junction conditions for this higher-derivative gravity. The extended spacetime obeys Friedmann and Raychaudhuri equations and the junction conditions. The junction does not generate Dirac delta functions in matter sources which keeps the equation of state unchanged.
ERIC Educational Resources Information Center
Basran, Jenny F. S.; Dal Bello-Haas, Vanina; Walker, Doreen; MacLeod, Peggy; Allen, Bev; D'Eon, Marcel; McKague, Meredith; Chopin, Nicola S.; Trinder, Krista
2012-01-01
The University of Saskatchewan's Longitudinal Elderly Person Shadowing (LEPS) is an interprofessional senior mentors program (SMP) where teams of undergraduate students in their first year of medicine, pharmacy, and physiotherapy; 2nd year of nutrition; 3rd year nursing; and 4th year social work partner with community-dwelling older adults.…
Chinnadayyala, Somasekhar R; Kakoti, Ankana; Santhosh, Mallesh; Goswami, Pranab
2014-05-15
Alcohol oxidase (AOx) with a two-fold increase in efficiency (Kcat/Km) was achieved by physical entrapment of the activator ferrocene in the protein matrix through a simple microwave based partial unfolding technique and was used to develop a 3rd generation biosensor for improved detection of alcohol in liquid samples. The ferrocene molecules were stably entrapped in the AOx protein matrix in a molar ratio of ~3:1 through electrostatic interaction with the Trp residues involved in the functional activity of the enzyme as demonstrated by advanced analytical techniques. The sensor was fabricated by immobilizing ferrocene entrapped alcohol oxidase (FcAOx) and sol-gel chitosan film coated horseradish peroxidase (HRP) on a multi-walled carbon nanotube (MWCNT) modified glassy carbon electrode through layer-by-layer technique. The bioelectrode reactions involved the formation of H2O2 by FcAOx biocatalysis of substrate alcohol followed by HRP-catalyzed reduction of the liberated H2O2 through MWCNT supported direct electron transfer mechanism. The amperometric biosensor exhibited a linear response to alcohol in the range of 5.0 × 10(-6) to 30 × 10(-4)mol L(-1) with a detection limit of 2.3 × 10(-6) mol L(-1), and a sensitivity of 150 µA mM(-1) cm(-2). The biosensor response was steady for 28 successive measurements completed in a period of 5h and retained ~90% of the original response even after four weeks when stored at 4 °C. The biosensor was successfully applied for the determination of alcohol in commercial samples and its performance was validated by comparing with the data obtained by GC analyses of the samples.
NASA Astrophysics Data System (ADS)
Lee, Chulsung; Hsu, Dennis J.; Le, Michael H.; Darling, Cynthia L.; Fried, Daniel
2009-02-01
Previous studies have demonstrated that Polarization Sensitive Optical Coherence Tomography (PS-OCT) can be used to image the remineralization of early artificial caries lesion on smooth enamel surfaces of human and bovine teeth. However, most new dental decay is found in the pits and fissures of the occlusal surfaces of posterior dentition and it is in these high risk areas where the performance of new caries imaging devices need to be investigated. The purpose of this study was to demonstrate that PS-OCT can be used to measure the subsequent remineralization of artificial lesions produced in the pits and fissures of extracted 3rd molars. A PS-OCT system operating at 1310-nm was used to acquire polarization resolved images of occlusal surfaces exposed to a demineralizing solution at pH-4.5 followed by a fluoride containing remineralizing solution at pH-7.0 containing 2-ppm fluoride. The integrated reflectivity was calculated to a depth of 200-Âµm in the entire lesion area using an automated image processing algorithm. Although a well-defined surface zone was clearly resolved in only a few of the samples that underwent remineralization, the PS-OCT measurements indicated a significant (p<0.05) reduction in the integrated reflectivity between the severity of the lesions that were exposed to the remineralization solution and those that were not. The lesion depth and mineral loss were also measured with polarized light microscopy and transverse microradiography after sectioning the teeth. These results show that PS-OCT can be used to non-destructively monitor the remineralization potential of anti-caries agents in the important pits and fissures of the occlusal surface.
Yu, Yen-Ting; Hsieh, Wu-Shiun; Hsu, Chyong-Hsin; Chen, Li-Chiou; Lee, Wang-Tso; Chiu, Nan-Chang; Wu, Ying-Chin; Jeng, Suh-Fang
2013-11-01
The Bayley Scales of Infant and Toddler Development - 3rd Edition (Bayley-III) was updated to enhance its usefulness for contemporary child developmental assessment. However, recent data in Western countries have implicated the overestimation of child development by the new instrument. This study aimed to investigate the psychometric features of the Bayley-III for term and preterm infants in Taiwan. Forty-seven term infants and 167 preterm infants were prospectively examined with the Bayley Scales of Infant Development - 2nd Edition (BSID-II) and the Bayley-III at 6, 12, 18, and 24 months of age (corrected for prematurity). The psychometric properties examined included reliability, construct validity, and known-group validity. The intra- and inter-rater reliabilities of the Bayley-III were good to excellent. The correlations between the BSID-II and Bayley-III raw scores were good to excellent for the cognitive and motor items and low to excellent for the language items. Term infants achieved higher composite scores than preterm infants on all of the Bayley-III scales (p<0.05). However, their rates of developmental delay were lower than the previously established prevalence estimates. The Bayley-III cut-off composite score was adjusted 10-20, 1-13, and 12-24 points higher than 70 for optimal prediction of cognitive, language, and motor delay, respectively, as defined by the BSID-II index score<70. The Bayley-III is a reliable instrument that extends its previous edition, especially in early language assessment. However, the upward adjustment of its cut-off score is recommended for the accurate identification of developmental delay in term and preterm Taiwanese infants. PMID:24029804
Naked singularities as particle accelerators. II.
NASA Astrophysics Data System (ADS)
Patil, Mandar; Joshi, Pankaj S.; Malafarina, Daniele
2011-03-01
We generalize here our earlier results on particle acceleration by naked singularities. We showed recently [M. Patil and P. S. Joshi, Phys. Rev. DPRVDAQ1550-7998 82, 104049 (2010).10.1103/PhysRevD.82.104049] that the naked singularities that form due to the gravitational collapse of massive stars provide a suitable environment where particles could get accelerated and collide at arbitrarily high center-of-mass energies. However, we focused there only on the spherically symmetric gravitational collapse models, which were also assumed to be self-similar. In this paper, we broaden and generalize the result to all gravitational collapse models leading to the formation of a naked singularity as the final state of collapse, evolving from a regular initial data, without making any prior restrictive assumptions about the spacetime symmetries such as above. We show that, when the particles interact and collide near the Cauchy horizon, the energy of collision in the center-of-mass frame will be arbitrarily high, thus offering a window to the Planck scale physics. We also consider the issue of various possible physical mechanisms of generation of such very high-energy particles from the vicinity of naked singularity. We then construct a model of gravitational collapse to a timelike naked singularity to demonstrate the working of these ideas, where the pressure is allowed to be negative, but the energy conditions are respected. We show that a finite amount of mass-energy density has to be necessarily radiated away from the vicinity of the naked singularity as the collapse evolves. Therefore, the nature of naked singularities, both at the classical and quantum level, could play an important role in the process of particle acceleration, explaining the occurrence of highly energetic outgoing particles in the vicinity of the Cauchy horizon that participate in extreme high-energy collisions.
Naked singularities as particle accelerators. II
Patil, Mandar; Joshi, Pankaj S.; Malafarina, Daniele
2011-03-15
We generalize here our earlier results on particle acceleration by naked singularities. We showed recently [M. Patil and P. S. Joshi, Phys. Rev. D 82, 104049 (2010).] that the naked singularities that form due to the gravitational collapse of massive stars provide a suitable environment where particles could get accelerated and collide at arbitrarily high center-of-mass energies. However, we focused there only on the spherically symmetric gravitational collapse models, which were also assumed to be self-similar. In this paper, we broaden and generalize the result to all gravitational collapse models leading to the formation of a naked singularity as the final state of collapse, evolving from a regular initial data, without making any prior restrictive assumptions about the spacetime symmetries such as above. We show that, when the particles interact and collide near the Cauchy horizon, the energy of collision in the center-of-mass frame will be arbitrarily high, thus offering a window to the Planck scale physics. We also consider the issue of various possible physical mechanisms of generation of such very high-energy particles from the vicinity of naked singularity. We then construct a model of gravitational collapse to a timelike naked singularity to demonstrate the working of these ideas, where the pressure is allowed to be negative, but the energy conditions are respected. We show that a finite amount of mass-energy density has to be necessarily radiated away from the vicinity of the naked singularity as the collapse evolves. Therefore, the nature of naked singularities, both at the classical and quantum level, could play an important role in the process of particle acceleration, explaining the occurrence of highly energetic outgoing particles in the vicinity of the Cauchy horizon that participate in extreme high-energy collisions.
Treatment of singularities in cracked bodies
NASA Technical Reports Server (NTRS)
Shivakumar, K. N.; Raju, I. S.
1989-01-01
Three-dimensional finite-element analyses of middle-crack tension (M-T) and bend specimens subjected to mode I loadings were performed to study the stress singularity along the crack front. The specimen was modeled using 20-node isoparametric elements. The displacements and stresses from the analysis were used to estimate the power of singularities using a log-log regression analysis along the crack front. The analyses showed that finite-sized cracked bodies have two singular stress fields of the form rho = C sub o (theta, z) r to the -1/2 power + D sub o (theta, phi) R to the lambda rho power. The first term is the cylindrical singularity with the power -1/2 and is dominant over the middle 96 pct (for Poisson's ratio = 0.3) of the crack front and becomes nearly zero at the free surface. The second singularity is a vertex singularity with the vertex point located at the intersection of the crack front and the free surface. The second term is dominant at the free surface and becomes nearly zero away from the the boundary layer. The thickness of the boundary layer depends on Poisson's ratio of the material and is independent of the specimen type. The thickness of the boundary layer varied from 0 pct to about 5 pct of the total specimen thickness as Poisson's ratio varied from 0.0 to 0.45. Because there are two singular stress fields near the free surface, the strain energy release rate (G) is an appropriate parameter to measure the severity of the crack.
Resonance Van Hove singularities in wave kinetics
NASA Astrophysics Data System (ADS)
Shi, Yi-Kang; Eyink, Gregory L.
2016-10-01
Wave kinetic theory has been developed to describe the statistical dynamics of weakly nonlinear, dispersive waves. However, we show that systems which are generally dispersive can have resonant sets of wave modes with identical group velocities, leading to a local breakdown of dispersivity. This shows up as a geometric singularity of the resonant manifold and possibly as an infinite phase measure in the collision integral. Such singularities occur widely for classical wave systems, including acoustical waves, Rossby waves, helical waves in rotating fluids, light waves in nonlinear optics and also in quantum transport, e.g. kinetics of electron-hole excitations (matter waves) in graphene. These singularities are the exact analogue of the critical points found by Van Hove in 1953 for phonon dispersion relations in crystals. The importance of these singularities in wave kinetics depends on the dimension of phase space D =(N - 2) d (d physical space dimension, N the number of waves in resonance) and the degree of degeneracy δ of the critical points. Following Van Hove, we show that non-degenerate singularities lead to finite phase measures for D > 2 but produce divergences when D ≤ 2 and possible breakdown of wave kinetics if the collision integral itself becomes too large (or even infinite). Similar divergences and possible breakdown can occur for degenerate singularities, when D - δ ≤ 2, as we find for several physical examples, including electron-hole kinetics in graphene. When the standard kinetic equation breaks down, then one must develop a new singular wave kinetics. We discuss approaches from pioneering 1971 work of Newell & Aucoin on multi-scale perturbation theory for acoustic waves and field-theoretic methods based on exact Schwinger-Dyson integral equations for the wave dynamics.
Singular Value Decomposition of Pinhole SPECT Systems.
Palit, Robin; Kupinski, Matthew A; Barrett, Harrison H; Clarkson, Eric W; Aarsvold, John N; Volokh, Lana; Grobshtein, Yariv
2009-03-12
A single photon emission computed tomography (SPECT) imaging system can be modeled by a linear operator H that maps from object space to detector pixels in image space. The singular vectors and singular-value spectra of H provide useful tools for assessing system performance. The number of voxels used to discretize object space and the number of collection angles and pixels used to measure image space make the matrix dimensions H large. As a result, H must be stored sparsely which renders several conventional singular value decomposition (SVD) methods impractical. We used an iterative power methods SVD algorithm (Lanczos) designed to operate on very large sparsely stored matrices to calculate the singular vectors and singular-value spectra for two small animal pinhole SPECT imaging systems: FastSPECT II and M(3)R. The FastSPECT II system consisted of two rings of eight scintillation cameras each. The resulting dimensions of H were 68921 voxels by 97344 detector pixels. The M(3)R system is a four camera system that was reconfigured to measure image space using a single scintillation camera. The resulting dimensions of H were 50864 voxels by 6241 detector pixels. In this paper we present results of the SVD of each system and discuss calculation of the measurement and null space for each system.
Removing singular refractive indices with sculpted surfaces
Horsley, S. A. R.; Hooper, I. R.; Mitchell–Thomas, R. C.; Quevedo–Teruel, O.
2014-01-01
The advent of Transformation Optics established the link between geometry and material properties, and has resulted in a degree of control over electromagnetic fields that was previously impossible. For waves confined to a surface it is known that there is a simpler, but related, geometrical equivalence between the surface shape and the refractive index, and here we demonstrate that conventional devices possessing a singularity — that is, the requirement of an infinite refractive index — can be realised for waves confined to an appropriately sculpted surface. In particular, we redesign three singular omnidirectional devices: the Eaton lens, the generalized Maxwell Fish–Eye, and the invisible sphere. Our designs perfectly reproduce the behaviour of these singular devices, and can be achieved with simple isotropic media of low refractive index contrast. PMID:24786649
NASA Astrophysics Data System (ADS)
Dramićanin, Miroslav D.; Antić, Željka; Viana, Bruno
2013-11-01
The 3rd International Conference on the Physics of Optical Materials and Devices (ICOM2012) was held in Belgrade (Serbia) from 2 to 6 September 2012 (figure 1). The conference was organized by the Vinča Institute of Nuclear Sciences, University of Belgrade (Serbia) and the Laboratoire de Chimie de la Matière Condensée de Paris (France), and supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia and Optical Society of America. ICOM2012 was a follow-up to the two previous, successful ICOM conferences held in Herceg Novi in 2006 and 2009. The conference aimed at providing a forum for scientists in optical materials to debate on: • Luminescent materials and nanomaterials • Hybrid optical materials (organic/inorganic) • Characterization techniques of optical materials • Luminescence mechanisms and energy transfers • Theory and modeling of optical processes • Ultrafast-laser processing of materials • Optical sensors • Medical imaging • Advanced optical materials in photovoltaics and biophotonics • Photothermal and photoacoustic spectroscopy and phenomena The conference stressed the value of a fundamental scientific understanding of optical materials. A particular accent was put on wide band-gap materials in crystalline, glass and nanocrystalline forms. The applications mainly involved lasers, scintillators and phosphors. Rare earth and transition metal ions introduced as dopants in various hosts were considered, and their impact on the optical properties were detailed in several presentations. This volume contains selected contributions of speakers and participants of the ICOM2012 conference. The conference provided a unique opportunity for about 200 scientists from 32 countries to discuss recent progress in the field of optical materials. During the three and half days, 21 invited talks and 52 contributed lectures were given, with a special event in memory of our dear colleague Professor Dr Tsoltan
Class of supersymmetric solitons with naked singularities
Cvetic, M.; Youm, D. )
1995-02-15
We study vacuum domain walls in a class of four-dimensional [ital N]=1 supergravity theories where along with the matter field, forming the wall, there is more than one dilaton,'' each respecting SU(1,1) symmetry in their subsector. We find [ital supersymmetric] (planar, static) walls, interpolating between a Minkowski vacuum and a new class of supersymmetric vacua which have a naked (planar) singularity. Although such walls correspond to idealized configurations, i.e., they correspond to planar configurations of infinite extent, they provide the first example of supersymmetric classical solitons with naked singularities.
Timelike singularities and Hamiltonian cosmological billiards
NASA Astrophysics Data System (ADS)
Klinger, Paul
2016-06-01
We construct a large class of vacuum solutions of the Einstein equations without any symmetries and with controlled asymptotics near a timelike singularity. The solutions are obtained by a Fuchs analysis of the equations which evolve the metric in a spacelike direction. We further observe that the change of sign of some of the terms (walls) in the associated Hamiltonian invalidate the ‘cosmological billards’ heuristic arguments for the existence of singularities of the mixmaster type in the current context. UWThPh-2015-33
Wave Geometry: a Plurality of Singularities
NASA Astrophysics Data System (ADS)
Berry, M. V.
Five interconnected wave singularities are discussed: phase monopoles, at eigenvalue degeneracies in parameter space, where the 2-form generating the geomeeic phase is singular, phase dislocations, at zeros of complex wavefunctions in position space, where different wavefronts (surfaces of constant phase) meet; caustics, that is envelopes (foci) of families of classical paths or geometrical rays, where real rays are born violently and which are complementary to dislocations; Stokes sets, at which a complex ray is born gently where it is maximally dominated by another ray; and complex degeneracies, which are the sources of adiabatic quantum transtions in analytic Hamiltonians.
Quantum singularity of Levi-Civita spacetimes
NASA Astrophysics Data System (ADS)
Konkowski, D. A.; Helliwell, T. M.; Wieland, C.
2004-01-01
Quantum singularities in general relativistic spacetimes are determined by the behaviour of quantum test particles. A static spacetime is quantum mechanically singular if the spatial portion of the wave operator is not essentially self-adjoint. Here Weyl's limit point limit circle criterion is used to determine whether a wave operator is essentially self-adjoint. This test is then applied to scalar wave packets in Levi-Civita spacetimes to help elucidate the physical properties of the spacetimes in terms of their metric parameters.
Propagation of the Lissajous singularity dipole through an astigmatic lens
NASA Astrophysics Data System (ADS)
Chen, Haitao; Gao, Zenghui; Zou, Xuefang; Huang, Weigang; Wang, Fanhou
2013-11-01
The propagation was investigated of a pair of Lissajous singularities of opposite singularity index called the Lissajous singularity dipole (LSD) through an astigmatic lens. It is shown that after passing through the lens the positions of the singularities are inverted and more than two LSDs occur. Changes in the degree of polarization of the LSDs as well as in the shape of the Lissajous figures also occur. In addition, Lissajous singularities may take place at the focal plane, and a single Lissajous singularity may appear and vanish under certain conditions. The results are compared with those of previous work.
Wenz, Holger; Maros, Máté E.; Meyer, Mathias; Förster, Alex; Haubenreisser, Holger; Kurth, Stefan; Schoenberg, Stefan O.; Flohr, Thomas; Leidecker, Christianne; Groden, Christoph; Scharf, Johann; Henzler, Thomas
2015-01-01
Objectives To prospectively intra-individually compare image quality of a 3rd generation Dual-Source-CT (DSCT) spiral cranial CT (cCT) to a sequential 4-slice Multi-Slice-CT (MSCT) while maintaining identical intra-individual radiation dose levels. Methods 35 patients, who had a non-contrast enhanced sequential cCT examination on a 4-slice MDCT within the past 12 months, underwent a spiral cCT scan on a 3rd generation DSCT. CTDIvol identical to initial 4-slice MDCT was applied. Data was reconstructed using filtered backward projection (FBP) and 3rd-generation iterative reconstruction (IR) algorithm at 5 different IR strength levels. Two neuroradiologists independently evaluated subjective image quality using a 4-point Likert-scale and objective image quality was assessed in white matter and nucleus caudatus with signal-to-noise ratios (SNR) being subsequently calculated. Results Subjective image quality of all spiral cCT datasets was rated significantly higher compared to the 4-slice MDCT sequential acquisitions (p<0.05). Mean SNR was significantly higher in all spiral compared to sequential cCT datasets with mean SNR improvement of 61.65% (p*Bonferroni0.05<0.0024). Subjective image quality improved with increasing IR levels. Conclusion Combination of 3rd-generation DSCT spiral cCT with an advanced model IR technique significantly improves subjective and objective image quality compared to a standard sequential cCT acquisition acquired at identical dose levels. PMID:26288186
Quadrature methods for periodic singular and weakly singular Fredholm integral equations
NASA Technical Reports Server (NTRS)
Sidi, Avram; Israeli, Moshe
1988-01-01
High-accuracy numerical quadrature methods for integrals of singular periodic functions are proposed. These methods are based on the appropriate Euler-Maclaurin expansions of trapezoidal rule approximations and their extrapolations. They are subsequently used to obtain accurate quadrature methods for the solution of singular and weakly singular Fredholm integral equations. Throughout the development the periodic nature of the problem plays a crucial role. Such periodic equations are used in the solution of planar elliptic boundary value problems such as those that arise in elasticity, potential theory, conformal mapping, and free surface flows. The use of the quadrature methods is demonstrated with numerical examples.
Young Children's Comprehension of Person Pronouns.
ERIC Educational Resources Information Center
Steig, Janet B.; Arnold, Marjorie R.
A study was conducted to test the validity of the Linguistic Features Hypothesis, which predicts that unmarked personal pronouns will be learned first by children, yielding the following order of acquisition: first person before second, followed by third; singular before plural; and subjective case before objective or genitive. A review of the…
Personal Pronouns and Communicative Engagement in Autism
ERIC Educational Resources Information Center
Hobson, R. Peter; Lee, Anthony; Hobson, Jessica A.
2010-01-01
In three experimental conditions, we tested matched children with and without autism (n = 15 per group) for their comprehension and use of first person plural ("we") and third person singular ("he") pronouns, and examined whether such linguistic functioning related to their social interaction. The groups were indistinguishable in their…
A Sociolinguistic Analysis of Person References by Japanese and American Children.
ERIC Educational Resources Information Center
Ide, Sachiko
1979-01-01
Compares use of first person singular and second person singular references in Japanese and American children six years old and under. Hypothesizes that Japanese children use a greater variety of these forms and observe sex distinction in the use of these forms to a greater extent than American children. (Author/AM)
Singular Lyapunov spectra and conservation laws.
Bohr, T.; Grinstein, G.; Jayaprakash, C.
1995-06-01
We give analytic arguments and numerical evidence to show that the presence of conservation laws can produce a singularity in the spectrum of Lyapunov exponents for extended dynamical systems of low spatial dimensionality. This phenomenon can be used, e.g., for finding hidden conservation laws. (c) 1995 American Institute of Physics.
'Footballs', conical singularities, and the Liouville equation
Redi, Michele
2005-02-15
We generalize the football shaped extra dimensions scenario to an arbitrary number of branes. The problem is related to the solution of the Liouville equation with singularities, and explicit solutions are presented for the case of three branes. The tensions of the branes do not need to be tuned with each other but only satisfy mild global constraints.
Gravitational lensing by rotating naked singularities
Gyulchev, Galin N.; Yazadjiev, Stoytcho S.
2008-10-15
We model massive compact objects in galactic nuclei as stationary, axially symmetric naked singularities in the Einstein-massless scalar field theory and study the resulting gravitational lensing. In the weak deflection limit we study analytically the position of the two weak field images, the corresponding signed and absolute magnifications as well as the centroid up to post-Newtonian order. We show that there are static post-Newtonian corrections to the signed magnification and their sum as well as to the critical curves, which are functions of the scalar charge. The shift of the critical curves as a function of the lens angular momentum is found, and it is shown that they decrease slightly for the weakly naked and vastly for the strongly naked singularities with the increase of the scalar charge. The pointlike caustics drift away from the optical axis and do not depend on the scalar charge. In the strong deflection limit approximation, we compute numerically the position of the relativistic images and their separability for weakly naked singularities. All of the lensing quantities are compared to particular cases as Schwarzschild and Kerr black holes as well as Janis-Newman-Winicour naked singularities.
Modulated solitons at a singular Hopf bifurcation
Pismen, L.M.
1987-02-15
Dynamics near a singular Hopf bifurcation under conditions of nonlinear self-focusing is dominated by intermediate-scale solitons with amplitudes and speeds evolving on a slower time scale. The long-scale evolution can result in selection of either standing or propagating solitons with either stationary or oscillating amplitude and speed.
Strong curvature singularities and causal simplicity
Krolak, A. )
1992-02-01
Techniques of differential topology in Lorentzian manifolds developed by Geroch, Hawking, and Penrose are used to rule out a class of locally naked strong curvature singularities in strongly causal space-times. This result yields some support to the validity of Penrose's strong cosmic censorship hypothesis.
A survey on the structured singular value
NASA Technical Reports Server (NTRS)
Packard, Andy; Fan, Michael
1989-01-01
The structured singular value, U, is an important linear algebra tool to study a class of matrix perturbation problems. It is useful for analyzing the robustness of stability and performance of uncertain, (nominally) linear systems. Computation of (M) is difficult, and usually, upper and lower bounds are all that can be reliably computed. Upper bounds give conservative estimates of the sizes of allowable perturbations. The maximum singular value of a matrix M is an upper bound for (M). As an upper bound, it can be improved by finding a transformations to the data (i.e. M) which do not change the structured singular value, but do reduce the maximum singular value. Typically, upper bound algorithms involve searches over sets of transformations to yield the tightest bound. Lower bound algorithms are intelligent searches for minimum-norm solutions to multivariable polynomial equations, and are based on various optimality conditions that hold at the global (and, unfortunately, some local) minima. The current methods to compute both of these types of bounds are reviewed. Theoretical justification and extensive numerical experience with the various algorithms are covered.
The Singular, The Plural, and the Numberless.
ERIC Educational Resources Information Center
Gilsdorf, Jeanette
1986-01-01
Outlines major publishing houses' solutions to the common-gender singular pronoun problem. Maintains that the American English-speaking world employs different standards for speaking and writing, even in educated ranks. Argues that changing spoken language is probably hopeless. Proposes seven tactics through which to counter written grammar and…
A numerical method of detecting singularity
NASA Technical Reports Server (NTRS)
Laporte, M.; Vignes, J.
1978-01-01
A numerical method is reported which determines a value C for the degree of conditioning of a matrix. This value is C = 0 for a singular matrix and has progressively larger values for matrices which are increasingly well-conditioned. This value is C sub = C max sub max (C defined by the precision of the computer) when the matrix is perfectly well conditioned.
Singular behavior of jet substructure observables
Larkoski, Andrew J.; Moult, Ian
2016-01-20
Jet substructure observables play a central role at the Large Hadron Collider for identifying the boosted hadronic decay products of electroweak scale resonances. The complete description of these observables requires understanding both the limit in which hard substructure is resolved, as well as the limit of a jet with a single hard core. In this paper we study in detail the perturbative structure of two prominent jet substructure observables, N-subjettiness and the energy correlation functions, as measured on background QCD jets. In particular, we focus on the distinction between the limits in which two-prong structure is resolved or unresolved. Dependingmore » on the choice of subjet axes, we demonstrate that at fixed order, N-subjettiness can manifest myriad behaviors in the unresolved region: smooth tails, end-point singularities, or singularities in the physical region. The energy correlation functions, by contrast, only have non-singular perturbative tails extending to the end point. We discuss the effect of hadronization on the various observables with Monte Carlo simulation and demonstrate that the modeling of these effects with non-perturbative shape functions is highly dependent on the N-subjettiness axes definitions. Lastly, our study illustrates those regions of phase space that must be controlled for high-precision jet substructure calculations, and emphasizes how such calculations can be facilitated by designing substructure observables with simple singular structures.« less
Null cosmological singularities and free strings: II
NASA Astrophysics Data System (ADS)
Narayan, K.
2011-01-01
In
Singularity and Community: Levinas and Democracy
ERIC Educational Resources Information Center
Zhao, Guoping
2016-01-01
This article explores and extends Levinas's ideas of singularity and community as multiplicity and argues that his identification of language and discourse as the means to create ethical communities provides tangible possibilities for rebuilding genuine democracy in a humane world. These ideas help us reimagine school and classroom as communities…
Configuration-Control Scheme Copes With Singularities
NASA Technical Reports Server (NTRS)
Seraji, Homayoun; Colbaugh, Richard D.
1993-01-01
Improved configuration-control scheme for robotic manipulator having redundant degrees of freedom suppresses large joint velocities near singularities, at expense of small trajectory errors. Provides means to enforce order of priority of tasks assigned to robot. Basic concept of configuration control of redundant robot described in "Increasing The Dexterity Of Redundant Robots" (NPO-17801).
Dynamics of learning near singularities in layered networks.
Wei, Haikun; Zhang, Jun; Cousseau, Florent; Ozeki, Tomoko; Amari, Shun-Ichi
2008-03-01
We explicitly analyze the trajectories of learning near singularities in hierarchical networks, such as multilayer perceptrons and radial basis function networks, which include permutation symmetry of hidden nodes, and show their general properties. Such symmetry induces singularities in their parameter space, where the Fisher information matrix degenerates and odd learning behaviors, especially the existence of plateaus in gradient descent learning, arise due to the geometric structure of singularity. We plot dynamic vector fields to demonstrate the universal trajectories of learning near singularities. The singularity induces two types of plateaus, the on-singularity plateau and the near-singularity plateau, depending on the stability of the singularity and the initial parameters of learning. The results presented in this letter are universally applicable to a wide class of hierarchical models. Detailed stability analysis of the dynamics of learning in radial basis function networks and multilayer perceptrons will be presented in separate work.
Generalized Parton Distributions and their Singularities
Anatoly Radyushkin
2011-04-01
A new approach to building models of generalized parton distributions (GPDs) is discussed that is based on the factorized DD (double distribution) Ansatz within the single-DD formalism. The latter was not used before, because reconstructing GPDs from the forward limit one should start in this case with a very singular function $f(\\beta)/\\beta$ rather than with the usual parton density $f(\\beta)$. This results in a non-integrable singularity at $\\beta=0$ exaggerated by the fact that $f(\\beta)$'s, on their own, have a singular $\\beta^{-a}$ Regge behavior for small $\\beta$. It is shown that the singularity is regulated within the GPD model of Szczepaniak et al., in which the Regge behavior is implanted through a subtracted dispersion relation for the hadron-parton scattering amplitude. It is demonstrated that using proper softening of the quark-hadron vertices in the regions of large parton virtualities results in model GPDs $H(x,\\xi)$ that are finite and continuous at the "border point'' $x=\\xi$. Using a simple input forward distribution, we illustrate the implementation of the new approach for explicit construction of model GPDs. As a further development, a more general method of regulating the $\\beta=0$ singularities is proposed that is based on the separation of the initial single DD $f(\\beta, \\alpha)$ into the "plus'' part $[f(\\beta,\\alpha)]_{+}$ and the $D$-term. It is demonstrated that the "DD+D'' separation method allows to (re)derive GPD sum rules that relate the difference between the forward distribution $f(x)=H(x,0)$ and the border function $H(x,x)$ with the $D$-term function $D(\\alpha)$.
Generalized parton distributions and their singularities
Radyushkin, A. V.
2011-04-01
A new approach to building models of generalized parton distributions (GPDs) is discussed that is based on the factorized DD (double distribution) ansatz within the single-DD formalism. The latter was not used before, because reconstructing GPDs from the forward limit one should start in this case with a very singular function f({beta})/{beta} rather than with the usual parton density f({beta}). This results in a nonintegrable singularity at {beta}=0 exaggerated by the fact that f({beta})'s, on their own, have a singular {beta}{sup -a} Regge behavior for small {beta}. It is shown that the singularity is regulated within the GPD model of Szczepaniak et al., in which the Regge behavior is implanted through a subtracted dispersion relation for the hadron-parton scattering amplitude. It is demonstrated that using proper softening of the quark-hadron vertices in the regions of large parton virtualities results in model GPDs H(x,{xi}) that are finite and continuous at the 'border point' x={xi}. Using a simple input forward distribution, we illustrate implementation of the new approach for explicit construction of model GPDs. As a further development, a more general method of regulating the {beta}=0 singularities is proposed that is based on the separation of the initial single DD f({beta},{alpha}) into the 'plus' part [f({beta},{alpha})]{sub +} and the D term. It is demonstrated that the ''DD+D'' separation method allows one to (re)derive GPD sum rules that relate the difference between the forward distribution f(x)=H(x,0) and the border function H(x,x) with the D-term function D({alpha}).
EDITORIAL: The plurality of optical singularities
NASA Astrophysics Data System (ADS)
Berry, Michael; Dennis, Mark; Soskin, Marat
2004-05-01
This collection of papers arose from an Advanced Research Workshop on Singular Optics, held at the Bogolyubov Institute in Kiev, Ukraine, during 24-28 June 2003. The workshop was generously financed by NATO, with welcome additional support from Institute of Physics Publishing and the National Academy of Sciences of Ukraine. There had been two previous international meetings devoted to singular optics, in Crimea in 1997 and 2000, reflecting the strong involvement of former Soviet Union countries in this research. Awareness of singular optics is growing within the wider optics community, indicated by symposia on the subject at several general optics meetings. As the papers demonstrate, the field of singular optics has reached maturity. Although the subject originated in an observation on ultrasound, it has been largely theory-driven until recently. Now, however, there is close contact between theory and experiment, and we speculate that this is one reason for its accelerated development. To single out particular papers for mention here would be invidious, and since the papers speak for themselves it is not necessary to describe them all. Instead, we will confine ourselves to a brief description of the main areas included in singular optics, to illustrate the broad scope of the subject. Optical vortices are lines of phase singularity: nodal lines where the intensity of the light, represented by a complex scalar field, vanishes. The subject has emerged from flatland, where the vortices are points characterized by topological charges, into the much richer world of vortex lines in three dimensions. By combining Laguerre-Gauss or Bessel beams, or reflecting light from plates with spiral steps, intricate arrangements can be generated, with vortices that are curved, looped, knotted, linked or braided. With light whose state of polarization varies with position, different singularities occur, associated with the vector nature of light. These are also lines, on which the
Resolution of SU (2) monopole singularities by oxidation
NASA Astrophysics Data System (ADS)
Bueno, Pablo; Meessen, Patrick; Ortín, Tomás; Ramírez, Pedro F.
2015-06-01
We show how colored SU (2) BPS monopoles (that is: SU (2) monopoles satisfying the Bogomol'nyi equation whose Higgs field and magnetic charge vanish at infinity and which are singular at the origin) can be obtained from the BPST instanton by a singular dimensional reduction, explaining the origin of the singularity and implying that the singularity can be cured by the oxidation of the solution. We study the oxidation of other monopole solutions in this scheme.
Persistence of the Hopf bifurcation under singular perturbations
Abed, E.H.
1984-05-01
The purpose of this paper is to study persistence of the Hopf bifurcation under singular perturbations of the associated vector field. Both single parameter and multiparameter singular perturbation problems are considered. In each case, hyperbolicity of an associated fast time system is shown to imply persistence. For single parameter singular perturbation problems, we employ Fenichel's center manifold theorem for singularly perturbed systems (1) to prove regular degeneration of the bifurcated periodic solutions and to study their stability.
NASA Astrophysics Data System (ADS)
2016-02-01
The iMEC 2015 is the second International Manufacturing Engineering Conference organized by the Faculty of Manufacturing, Universiti Malaysia Pahang (UMP), held from 12-14th November 2015 in Kuala Lumpur, Malaysia, with a theme "Materials, Manufacturing and Systems for Tomorrow". For the first time, iMEC is organized together with 3rd Asia- Pacific Conference on Manufacturing System (APCOMS 2015) which owned by Fakulti Teknologi Industri, Institut Teknologi Bandung (ITB), Indonesia. This is an extended collaboration between UMP and ITB to intensify knowledge sharing and experiences between higher learning institutions. This conference (iMEC & APCOMS 2015) is a platform for knowledge exchange and the growth of ideas, particularly in manufacturing engineering. The conference aims to bring researchers, academics, scientists, students, engineers and practitioners from around the world together to present their latest findings, ideas, developments and applications related to manufacturing engineering and other related research areas. With rapid advancements in manufacturing engineering, iMEC is an appropriate medium for the associated community to keep pace with the changes. In 2015, the conference theme is “Materials, Manufacturing and Systems for Tomorrow” which reflects the acceleration of knowledge and technology in global manufacturing. The papers in these proceedings are examples of the work presented at the conference. They represent the tip of the iceberg, as the conference attracted over 200 abstracts from Malaysia, Indonesia, Japan, United Kingdom, Australia, India, Bangladesh, South Africa, Turkey and Morocco and 151 full papers were accepted in these proceedings. The conference was run in four parallel sessions with 160 presenters sharing their latest finding in the areas of manufacturing process, systems, advanced materials and automation. The first keynote presentation was given by Prof. B. S. Murthy (IIT, Madras) on "Nanomaterials with Exceptional
NASA Astrophysics Data System (ADS)
Linsenbarth, Adam
2012-09-01
The paper presents consecutive stages of the evolution of geoinformation related to the territories of the events described in the Bible. Two geoinformation sources are presented: the Bible and non-Bible sources. In the Bible there is much, often some highly detailed information regarding terrain topography. The oldest non-Bible sources are incorporated in the ancient documents, which were discovered in Egypt and Mesopotamia. Some of them are related to the 3rd millen- nium B.C. The further stages are related to the onomasticons and itineraries written by travellers and pilgrims to the Holy Land. The most famous onomasticons include: onomasticons prepared by bishop Eusebius from Caesarea and those pre- pared by St. Jerome. One of the oldest maps of Palestine's territory is the so-called mosaic map of Madaba dated to 565. In the 15th century several Bible maps were edited. The most rapid evolution occurred in the 16th and 17* centuries, when the world famous cartographers such as Mercator and Ortelius edited several maps of Palestine's territory. Cartographers from several European countries edited more than 6,000 maps presenting the Biblical territories and Biblical events. Modem maps, based on detailed topographical surveys, were edited m the second half of the 19* and 20th centuries. W artykule przedstawiono kolejne etapy rozwoju geoinformacji dotyczącej terenówr biblijnych. Omówiono dwa źródła informacji, a mianowicie geoinformacje biblijne i pozabiblijne. W tekstach biblijnych można znaleźć wiele, często bardzo detalicznych informacji topograficznych. Najstarsze źródła pozabiblijne, to starożytne dokumenty odnalezione na terenach Egiptu i Mezopotamii. Niektóre z nich pochodzą z trzeciego milenium przed Chr. Kolejnym etapem geoinformacji były onomastikony oraz dzienniki podróży pisane przez podróżników i pielgrzymów do Ziemi Świętej. Do najbardziej znanych należy onomastikon sporządzony przez biskupa Euzebiusza z Cezarei oraz
Adam, Z; Pejchalová, A; Chlupová, G; Ríhová, L; Pour, L; Krejčí, M; Cervinek, L; Král, Z; Mayer, J
2013-09-01
in about one half of treated patients and the remission duration median after rituximab administration is 11 months. A combination of rituximab with fludarabin was more effective, though more toxic; this combination, in a clinical study, led to 75% of patients responding to treatment, including 20% experiencing complete remission. The treatment response median reached over 66 months. In a small study (10 patients) an increase in the amount of rituximab administrations from 4 to 8 led to a treatment response in 6 patients in whom administration of 4 doses of rituximab had no response. When treating Waldenström macroglobulinemia, effectiveness of the following drugs and their combinations was proven: rituximab, chlorambucil, cyclophosphamide, fludarabin, bortezomib, lenalidomid, bendamustin and alemtuzumab. The same drugs and treatment procedures are used for the treatment of the cold agglutinin disease as for Waldenström macroglobulinemia. Successful treatment with vortezomibem, combinations of rituximab + bendamustin, rituximab + cyclophosphamide or rituximab + fludarabin + cyclophosphamide, were recorded in the form of a description as regards the cold agglutinin disease treatment. An important benefit is also shown through treatment with the monoclonal antibody antiC5, eculizumab, which is otherwise used for the treatment of paroxysmal nocturnal haemoglobinuria. Eculizumab blocks the C5 element of the component and thus stops haemolysis in a patient with cold agglutinin disease. As cold agglutinin disease is very rare, there are only a few clinical studies and when treating this rare disease we have no other option than to take into account the information contained in the descriptions of the particular cases of cold agglutinin disease and the experience of Waldenström macroglobulinemia disease treatment. The discussion seeks to solve the issue regarding what 3rd line treatment option to use in the described patient. PMID:24073955
32 CFR 1602.22 - Singular and plural.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 32 National Defense 6 2012-07-01 2012-07-01 false Singular and plural. 1602.22 Section 1602.22 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM DEFINITIONS § 1602.22 Singular and plural. Words importing the singular number shall include the plural number,...
32 CFR 1602.22 - Singular and plural.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 32 National Defense 6 2011-07-01 2011-07-01 false Singular and plural. 1602.22 Section 1602.22 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM DEFINITIONS § 1602.22 Singular and plural. Words importing the singular number shall include the plural number,...
32 CFR 1602.22 - Singular and plural.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 32 National Defense 6 2014-07-01 2014-07-01 false Singular and plural. 1602.22 Section 1602.22 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM DEFINITIONS § 1602.22 Singular and plural. Words importing the singular number shall include the plural number,...
32 CFR 1602.22 - Singular and plural.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 32 National Defense 6 2013-07-01 2013-07-01 false Singular and plural. 1602.22 Section 1602.22 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM DEFINITIONS § 1602.22 Singular and plural. Words importing the singular number shall include the plural number,...
32 CFR 1602.22 - Singular and plural.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 32 National Defense 6 2010-07-01 2010-07-01 false Singular and plural. 1602.22 Section 1602.22 National Defense Other Regulations Relating to National Defense SELECTIVE SERVICE SYSTEM DEFINITIONS § 1602.22 Singular and plural. Words importing the singular number shall include the plural number,...
Behavior of Friedmann-Lemaître-Robertson-Walker Singularities
NASA Astrophysics Data System (ADS)
Fernández-Jambrina, L.
2016-08-01
In Stoica (Int. J. Theor. Phys. 55, 71-80, 2016) a regularization procedure is suggested for regularizing Big Bang singularities in Friedmann-Lemaître-Robertson-Walker (FLRW) spacetimes. We argue that this procedure is only appliable to one case of Big Bang singularities and does not affect other types of singularities.
Spectral singularities and Bragg scattering in complex crystals
Longhi, S.
2010-02-15
Spectral singularities that spoil the completeness of Bloch-Floquet states may occur in non-Hermitian Hamiltonians with complex periodic potentials. Here an equivalence is established between spectral singularities in complex crystals and secularities that arise in Bragg diffraction patterns. Signatures of spectral singularities in a scattering process with wave packets are elucidated for a PT-symmetric complex crystal.
7 CFR 1200.50 - Words in the singular form.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 10 2010-01-01 2010-01-01 false Words in the singular form. 1200.50 Section 1200.50 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING....50 Words in the singular form. Words in this subpart in the singular form shall be deemed to...
7 CFR 900.36 - Words in the singular form.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Words in the singular form. 900.36 Section 900.36 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Marketing Orders § 900.36 Words in the singular form. Words in this subpart in the singular form shall...
7 CFR 900.50 - Words in the singular form.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Words in the singular form. 900.50 Section 900.50 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Words in the singular form. Words in this subpart in the singular form shall be deemed to import...
7 CFR 900.1 - Words in the singular form.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Words in the singular form. 900.1 Section 900.1 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Words in the singular form. Words in this subpart in the singular form shall be deemed to import...
7 CFR 46.1 - Words in singular form.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 2 2010-01-01 2010-01-01 false Words in singular form. 46.1 Section 46.1 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Words in singular form. Words in this part in the singular form shall be deemed to import the...
7 CFR 900.100 - Words in the singular form.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Words in the singular form. 900.100 Section 900.100 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... Words in the singular form. Words in this subpart in the singular form shall be deemed to import...
7 CFR 900.20 - Words in the singular form.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Words in the singular form. 900.20 Section 900.20 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing... § 900.20 Words in the singular form. Words in this subpart in the singular form shall be deemed...
7 CFR 61.1 - Words in singular form.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 3 2010-01-01 2010-01-01 false Words in singular form. 61.1 Section 61.1 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Words in singular form. Words used in the regulations in this subpart in the singular form shall...
Singularities and the geometry of spacetime
NASA Astrophysics Data System (ADS)
Hawking, Stephen
2014-11-01
The aim of this essay is to investigate certain aspects of the geometry of the spacetime manifold in the General Theory of Relativity with particular reference to the occurrence of singularities in cosmological solutions and their relation with other global properties. Section 2 gives a brief outline of Riemannian geometry. In Section 3, the General Theory of Relativity is presented in the form of two postulates and two requirements which are common to it and to the Special Theory of Relativity, and a third requirement, the Einstein field equations, which distinguish it from the Special Theory. There does not seem to be any alternative set of field equations which would not have some undeseriable features. Some exact solutions are described. In Section 4, the physical significance of curvature is investigated using the deviation equation for timelike and null curves. The Riemann tensor is decomposed into the Ricci tensor which represents the gravitational effect at a point of matter at that point and the Welyl tensor which represents the effect at a point of gravitational radiation and matter at other points. The two tensors are related by the Bianchi identities which are presented in a form analogous to the Maxwell equations. Some lemmas are given for the occurrence of conjugate points on timelike and null geodesics and their relation with the variation of timelike and null curves is established. Section 5 is concerned with properties of causal relations between points of spacetime. It is shown that these could be used to determine physically the manifold structure of spacetime if the strong causality assumption held. The concepts of a null horizon and a partial Cauchy surface are introduced and are used to prove a number of lemmas relating to the existence of a timelike curve of maximum length between two sets. In Section 6, the definition of a singularity of spacetime is given in terms of geodesic incompleteness. The various energy assumptions needed to prove
First-person perspective effects on theory of mind without self-reference.
Otsuka, Yuki; Osaka, Naoyuki; Yaoi, Ken; Osaka, Mariko
2011-01-01
This study examined dissociations between brain networks involved in theory of mind, which is needed for guessing others' mental states, and the self, which might constitute the basis for theory of mind's development. We used event-related fMRI to compare a condition that required participants to guess the mental state of a subject featured in first-person perspective sentences (1stPP condition) with a third-person perspective sentence condition (3rdPP condition). The caudate nucleus was marginally more activated in the 1stPP than in the 3rdPP condition, while the left dorsolateral prefrontal cortex (DLPFC) was significantly more activated in the 3rdPP condition as compared to the 1stPP condition. Furthermore, we examined the correlation between activation (signal intensity) of the caudate nucleus and left DLPFC with that of the right DLPFC, which is thought to be closely connected with sense of self. We found a significant correlation between caudate nucleus and right DLPFC activation in the 1stPP condition, and between left and right DLPFC activation in the 3rdPP condition. Although theory of mind and the self both appear to recruit the right DLPFC, this region seems to be accessed through the left DLPFC during theory of mind tasks, but through the caudate nucleus when tasks require self reference. PMID:21559448
First-Person Perspective Effects on Theory of Mind without Self-Reference
Otsuka, Yuki; Osaka, Naoyuki; Yaoi, Ken; Osaka, Mariko
2011-01-01
This study examined dissociations between brain networks involved in theory of mind, which is needed for guessing others' mental states, and the self, which might constitute the basis for theory of mind's development. We used event-related fMRI to compare a condition that required participants to guess the mental state of a subject featured in first-person perspective sentences (1stPP condition) with a third-person perspective sentence condition (3rdPP condition). The caudate nucleus was marginally more activated in the 1stPP than in the 3rdPP condition, while the left dorsolateral prefrontal cortex (DLPFC) was significantly more activated in the 3rdPP condition as compared to the 1stPP condition. Furthermore, we examined the correlation between activation (signal intensity) of the caudate nucleus and left DLPFC with that of the right DLPFC, which is thought to be closely connected with sense of self. We found a significant correlation between caudate nucleus and right DLPFC activation in the 1stPP condition, and between left and right DLPFC activation in the 3rdPP condition. Although theory of mind and the self both appear to recruit the right DLPFC, this region seems to be accessed through the left DLPFC during theory of mind tasks, but through the caudate nucleus when tasks require self reference. PMID:21559448
NASA Technical Reports Server (NTRS)
Khayat, Michael A.; Wilton, Donald R.; Fink, Patrick W.
2007-01-01
Simple and efficient numerical procedures using singularity cancellation methods are presented for evaluating singular and near-singular potential integrals. Four different transformations are compared and the advantages of the Radial-angular transform are demonstrated. A method is then described for optimizing this integration scheme.
Singularity theory of fitness functions under dimorphism equivalence.
Wang, Xiaohui; Golubitsky, Martin
2016-09-01
We apply singularity theory to classify monomorphic singular points as they occur in adaptive dynamics. Our approach is based on a new equivalence relation called dimorphism equivalence, which is the largest equivalence relation on strategy functions that preserves ESS singularities, CvSS singularities, and dimorphisms. Specifically, we classify singularities up to topological codimension two and compute their normal forms and universal unfoldings. These calculations lead to the classification of local mutual invasibility plots that can be seen generically in systems with two parameters.
Does loop quantum cosmology replace the big rip singularity by a non-singular bounce?
Haro, Jaume de
2012-11-01
It is stated that holonomy corrections in loop quantum cosmology introduce a modification in Friedmann's equation which prevent the big rip singularity. Recently in [1] it has been proved that this modified Friedmann equation is obtained in an inconsistent way, what means that the results deduced from it, in particular the big rip singularity avoidance, are not justified. The problem is that holonomy corrections modify the gravitational part of the Hamiltonian of the system leading, after Legendre's transformation, to a non covariant Lagrangian which is in contradiction with one of the main principles of General Relativity. A more consistent way to deal with the big rip singularity avoidance is to disregard modification in the gravitational part of the Hamiltonian, and only consider inverse volume effects [2]. In this case we will see that, not like the big bang singularity, the big rip singularity survives in loop quantum cosmology. Another way to deal with the big rip avoidance is to take into account geometric quantum effects given by the the Wheeler-De Witt equation. In that case, even though the wave packets spread, the expectation values satisfy the same equations as their classical analogues. Then, following the viewpoint adopted in loop quantum cosmology, one can conclude that the big rip singularity survives when one takes into account these quantum effects. However, the spreading of the wave packets prevents the recover of the semiclassical time, and thus, one might conclude that the classical evolution of the universe come to and end before the big rip is reached. This is not conclusive because. as we will see, it always exists other external times that allows us to define the classical and quantum evolution of the universe up to the big rip singularity.
Characterizing maximally singular phase-space distributions
NASA Astrophysics Data System (ADS)
Sperling, J.
2016-07-01
Phase-space distributions are widely applied in quantum optics to access the nonclassical features of radiations fields. In particular, the inability to interpret the Glauber-Sudarshan distribution in terms of a classical probability density is the fundamental benchmark for quantum light. However, this phase-space distribution cannot be directly reconstructed for arbitrary states, because of its singular behavior. In this work, we perform a characterization of the Glauber-Sudarshan representation in terms of distribution theory. We address important features of such distributions: (i) the maximal degree of their singularities is studied, (ii) the ambiguity of representation is shown, and (iii) their dual space for nonclassicality tests is specified. In this view, we reconsider the methods for regularizing the Glauber-Sudarshan distribution for verifying its nonclassicality. This treatment is supported with comprehensive examples and counterexamples.
Singularity resolution from polymer quantum matter
NASA Astrophysics Data System (ADS)
Kreienbuehl, Andreas; Pawłowski, Tomasz
2013-08-01
We study the polymeric nature of quantum matter fields using the example of a Friedmann-Lemaître-Robertson-Walker universe sourced by a minimally coupled massless scalar field. The model is treated in the symmetry reduced regime via deparametrization techniques, with the scale factor playing the role of time. Subsequently, the remaining dynamic degrees of freedom corresponding to the matter are polymer quantized. The analysis of the resulting genuine quantum dynamic shows that the big bang singularity is resolved, although with the form of the resolution differing significantly from that in the models with matter clocks: dynamically, the singularity is made passable rather than avoided. Furthermore, this analysis exposes crucial limitations to the so-called effective dynamic in loop quantum cosmology when applied outside of the most basic isotropic settings.
Singular Jets and Bubbles in Drop Impact
NASA Astrophysics Data System (ADS)
Bartolo, Denis; Josserand, Christophe; Bonn, Daniel
2006-03-01
We show that when water droplets gently impact on a hydrophobic surface, the droplet shoots out a violent jet, the velocity of which can be up to 40 times the drop impact speed. As a function of the impact velocity, two different hydrodynamic singularities are found that correspond to the collapse of the air cavity formed by the deformation of the drop at impact. It is the collapse that subsequently leads to the jet formation. We show that the divergence of the jet velocity can be understood using simple scaling arguments. In addition, we find that very large air bubbles can remain trapped in the drops. The surprising occurrence of the bubbles for low-speed impact is connected with the nature of the singularities, and can have important consequences for drop deposition, e.g., in ink-jet printing.
Global dynamics in the singular logarithmic potential
NASA Astrophysics Data System (ADS)
Stoica, Cristina; Font, Andreea
2003-07-01
We present an analytical description of the motion in the singular logarithmic potential of the form Phi = ln surdx21/b2 + x22, a potential which plays an important role in the modelling of triaxial systems (such as elliptical galaxies) or bars in the centres of galaxy discs. In order to obtain information about the motion near the singularity, we resort to McGehee-type transformations and regularize the vector field. In the axis-symmetric case (b = 1), we offer a complete description of the global dynamics. In the non-axis-symmetric case (b < 1), we prove that all orbits, with the exception of a negligible set, are centrophobic and retrieve numerically partial aspects of the orbital structure.
ERIC Educational Resources Information Center
National Indian Council on Aging, Albuquerque, NM.
Focusing on six major topics to be addressed at the 1981 White House Conference (economic security, physical and mental health, social well being, older Americans as a national resource, creating an age-integrated society, and research), the National Indian Conference attracted 1,165 persons from more than 140 tribes (592 being Indian elders over…
ERIC Educational Resources Information Center
Pavlekovic, Margita, Ed.
2011-01-01
In the monograph The Math Teacher (following the Third International Scientific Colloquium Mathematics and Children in 2011), the term "teacher" designates a person who teaches mathematics, and the context of each article reveals whether this implies the teacher at a pre-school institution, a school or a university instructor. In Croatia, much…
Stability of the nakedness of Weyl singularities
NASA Technical Reports Server (NTRS)
Haugan, M. P.; Liang, E. P. T.
1979-01-01
The stability of the nakedness of the Weyl singularities against matter perturbations is investigated. Consideration is given to the effects of infalling test matter on the convergence of outgoing null rays. It is shown that the additional convergence induced by infalling test matter does not blow up sufficiently fast to reconverge diverging outgoing rays, at least in the equator, and that the nakedness seems to be stable in this limited sense.
Hardware Implementation of Singular Value Decomposition
NASA Astrophysics Data System (ADS)
Majumder, Swanirbhar; Shaw, Anil Kumar; Sarkar, Subir Kumar
2016-06-01
Singular value decomposition (SVD) is a useful decomposition technique which has important role in various engineering fields such as image compression, watermarking, signal processing, and numerous others. SVD does not involve convolution operation, which make it more suitable for hardware implementation, unlike the most popular transforms. This paper reviews the various methods of hardware implementation for SVD computation. This paper also studies the time complexity and hardware complexity in various methods of SVD computation.
Space-time singularities in Weyl manifolds
NASA Astrophysics Data System (ADS)
Lobo, I. P.; Barreto, A. B.; Romero, C.
2015-09-01
We extend one of the Hawking-Penrose singularity theorems in general relativity to the case of some scalar-tensor gravity theories in which the scalar field has a geometrical character and space-time has the mathematical structure of a Weyl integrable space-time. We adopt an invariant formalism, so that the extended version of the theorem does not depend on a particular frame.
Edward Jero, S; Ramu, Palaniappan; Ramakrishnan, S
2014-10-01
ECG Steganography provides secured transmission of secret information such as patient personal information through ECG signals. This paper proposes an approach that uses discrete wavelet transform to decompose signals and singular value decomposition (SVD) to embed the secret information into the decomposed ECG signal. The novelty of the proposed method is to embed the watermark using SVD into the two dimensional (2D) ECG image. The embedding of secret information in a selected sub band of the decomposed ECG is achieved by replacing the singular values of the decomposed cover image by the singular values of the secret data. The performance assessment of the proposed approach allows understanding the suitable sub-band to hide secret data and the signal degradation that will affect diagnosability. Performance is measured using metrics like Kullback-Leibler divergence (KL), percentage residual difference (PRD), peak signal to noise ratio (PSNR) and bit error rate (BER). A dynamic location selection approach for embedding the singular values is also discussed. The proposed approach is demonstrated on a MIT-BIH database and the observations validate that HH is the ideal sub-band to hide data. It is also observed that the signal degradation (less than 0.6%) is very less in the proposed approach even with the secret data being as large as the sub band size. So, it does not affect the diagnosability and is reliable to transmit patient information. PMID:25187409
Edward Jero, S; Ramu, Palaniappan; Ramakrishnan, S
2014-10-01
ECG Steganography provides secured transmission of secret information such as patient personal information through ECG signals. This paper proposes an approach that uses discrete wavelet transform to decompose signals and singular value decomposition (SVD) to embed the secret information into the decomposed ECG signal. The novelty of the proposed method is to embed the watermark using SVD into the two dimensional (2D) ECG image. The embedding of secret information in a selected sub band of the decomposed ECG is achieved by replacing the singular values of the decomposed cover image by the singular values of the secret data. The performance assessment of the proposed approach allows understanding the suitable sub-band to hide secret data and the signal degradation that will affect diagnosability. Performance is measured using metrics like Kullback-Leibler divergence (KL), percentage residual difference (PRD), peak signal to noise ratio (PSNR) and bit error rate (BER). A dynamic location selection approach for embedding the singular values is also discussed. The proposed approach is demonstrated on a MIT-BIH database and the observations validate that HH is the ideal sub-band to hide data. It is also observed that the signal degradation (less than 0.6%) is very less in the proposed approach even with the secret data being as large as the sub band size. So, it does not affect the diagnosability and is reliable to transmit patient information.
H(infinity) filtering for fuzzy singularly perturbed systems.
Yang, Guang-Hong; Dong, Jiuxiang
2008-10-01
This paper considers the problem of designing H(infinity) filters for fuzzy singularly perturbed systems with the consideration of improving the bound of singular-perturbation parameter epsilon. First, a linear-matrix-inequality (LMI)-based approach is presented for simultaneously designing the bound of the singularly perturbed parameter epsilon, and H(infinity) filters for a fuzzy singularly perturbed system. When the bound of singularly perturbed parameter epsilon is not under consideration, the result reduces to an LMI-based design method for H(infinity) filtering of fuzzy singularly perturbed systems. Furthermore, a method is given for evaluating the upper bound of singularly perturbed parameter subject to the constraint that the considered system is to be with a prescribed H(infinity) performance bound, and the upper bound can be obtained by solving a generalized eigenvalue problem. Finally, numerical examples are given to illustrate the effectiveness of the proposed methods.
NASA Astrophysics Data System (ADS)
Kirezci, Cagil; Ozyurt Tarakcioglu, Gulizar
2016-04-01
Coastal development in Black Sea has increased in recent years. Therefore, careful monitoring of the storms and verification of numerical tools with reliable data has become important. Previous studies by Kirezci and Ozyurt (2015) investigated extreme events in Black Sea using different wind datasets (NCEP's CFSR and ECMWF's operational datasets) and different numerical tools (SWAN and Wavewatch III). These studies showed that significant effect to results is caused by the deep water source-sink terms (wave growth by wind, deep water dissipation of wave energy (whitecapping) and deep water non-linear wave-wave interactions). According to Timmermans(2015), uncertainty about wind forcing and the process of nonlinear wave-wave interactions are found to be dominant in numerical wave modelling. Therefore, in this study deep water source and sink term solution approaches of 3rd generation numerical tool (SWAN model) are tested, validated and compared using the selected extreme storms in Black Sea. 45 different storms and storm like events observed in Black Sea between years 1994-1999 are selected to use in the models. The storm selection depends on the instrumental wave data (significant wave heights, mean wave period and mean wave direction) obtained in NATO-TU Waves project by the deep water buoy measurements at Hopa, Sinop, Gelendzhik, and wind data (mean and peak wind speeds, storm durations) of the regarding events. 2 different wave growth by wind with the corresponding deep water dissipation terms and 3 different wave -wave interaction terms of SWAN model are used in this study. Wave growth by wind consist of two parts, linear growth which is explained by Cavaleri and Malanotte-Rizzoli(1981),and dominant exponential growth. There are two methods in SWAN model for exponential growth of wave, first one by Snyder et al. (1981), rescaled in terms of friction velocity by Komen et. al (1984) which is derived using driving wind speed at 10m elevation with related drag
NASA Astrophysics Data System (ADS)
Kirezci, Cagil; Ozyurt Tarakcioglu, Gulizar
2016-04-01
Coastal development in Black Sea has increased in recent years. Therefore, careful monitoring of the storms and verification of numerical tools with reliable data has become important. Previous studies by Kirezci and Ozyurt (2015) investigated extreme events in Black Sea using different wind datasets (NCEP's CFSR and ECMWF's operational datasets) and different numerical tools (SWAN and Wavewatch III). These studies showed that significant effect to results is caused by the deep water source-sink terms (wave growth by wind, deep water dissipation of wave energy (whitecapping) and deep water non-linear wave-wave interactions). According to Timmermans(2015), uncertainty about wind forcing and the process of nonlinear wave-wave interactions are found to be dominant in numerical wave modelling. Therefore, in this study deep water source and sink term solution approaches of 3rd generation numerical tool (SWAN model) are tested, validated and compared using the selected extreme storms in Black Sea. 45 different storms and storm like events observed in Black Sea between years 1994-1999 are selected to use in the models. The storm selection depends on the instrumental wave data (significant wave heights, mean wave period and mean wave direction) obtained in NATO-TU Waves project by the deep water buoy measurements at Hopa, Sinop, Gelendzhik, and wind data (mean and peak wind speeds, storm durations) of the regarding events. 2 different wave growth by wind with the corresponding deep water dissipation terms and 3 different wave -wave interaction terms of SWAN model are used in this study. Wave growth by wind consist of two parts, linear growth which is explained by Cavaleri and Malanotte-Rizzoli(1981),and dominant exponential growth. There are two methods in SWAN model for exponential growth of wave, first one by Snyder et al. (1981), rescaled in terms of friction velocity by Komen et. al (1984) which is derived using driving wind speed at 10m elevation with related drag
NASA Technical Reports Server (NTRS)
Ardema, M. D.
1979-01-01
Singular perturbation techniques are studied for dealing with singular arc problems by analyzing a relatively low-order but otherwise general system. This system encompasses many flight mechanic problems including Goddard's problem and a version of the minimum time-to-climb problem. Boundary layer solutions are constructed which are stable and reach the outer solution in a finite time. A uniformly valid composite solution is then formed from the reduced and boundary layer solutions. The value of the approximate solution is that it is relatively easy to obtain and does not involve singular arcs. To illustrate the utility of the results, the technique is used to obtain an approximate solution of a simplified version of the aircraft minimum time-to-climb problem.
Effects of finite-time singularities on gravitational waves
NASA Astrophysics Data System (ADS)
Kleidis, K.; Oikonomou, V. K.
2016-10-01
We analyze the impact of finite-time singularities on gravitational waves, in the context of F(R) gravity. We investigate which singularities are allowed to occur during the inflationary era, when gravitational waves are considered, and we discuss the quantitative implications of each allowed singularity. As we show, only a pressure singularity, the so-called Type II and also a Type IV singularity are allowed to occur during the inflationary era. In the case of a Type II, the resulting amplitude of the gravitational wave is zero or almost zero, hence this pressure singularity has a significant impact on the primordial gravitational waves. The case of a Type IV singularity is more interesting since as we show, the singularity has no effect on the amplitude of the gravitational waves. Therefore, this result combined with the fact that the Type IV singularity affects only the dynamics of inflation, leads to the conclusion that the Universe passes smoothly through a Type IV singularity.
Light-Front Perturbation Without Spurious Singularities
NASA Astrophysics Data System (ADS)
Przeszowski, Jerzy A.; Dzimida-Chmielewska, Elżbieta; Żochowski, Jan
2016-07-01
A new form of the light front Feynman propagators is proposed. It contains no energy denominators. Instead the dependence on the longitudinal subinterval x^2_L = 2 x+ x- is explicit and a new formalism for doing the perturbative calculations is invented. These novel propagators are implemented for the one-loop effective potential and various 1-loop 2-point functions for a massive scalar field. The consistency with results for the standard covariant Feynman diagrams is obtained and no spurious singularities are encountered at all. Some remarks on the calculations with fermion and gauge fields in QED and QCD are added.
Multigrid applied to singular perturbation problems
NASA Technical Reports Server (NTRS)
Kamowitz, David
1987-01-01
The solution of the singular perturbation problem by a multigrid algorithm is considered. Theoretical and experimental results for a number of different discretizations are presented. The theoretical and observed rates agree with the results developed in an earlier work of Kamowitz and Parter. In addition, the rate of convergence of the algorithm when the coarse grid operator is the natural finite difference analog of the fine grid operator is presented. This is in contrast to the case in the previous work where the Galerkin choice (I sup H sub h L sub h,I sup h sub H) was used for the coarse grid operators.
Enumeration of curves with one singular point
NASA Astrophysics Data System (ADS)
Basu, Somnath; Mukherjee, Ritwik
2016-06-01
In this paper we obtain an explicit formula for the number of curves in P2, of degree d, passing through (d(d + 3) / 2 - k) generic points and having a singularity X, where X is of type Ak≤7 ,Dk≤7 or Ek≤7. Our method comprises of expressing the enumerative problem as the Euler class of an appropriate bundle and using a purely topological method to compute the degenerate contribution to the Euler class. These numbers have also been computed by M. Kazarian using the existence of universal formulas for Thom polynomials.
Penrose's singularity theorem in a Finsler spacetime
NASA Astrophysics Data System (ADS)
Babak Aazami, Amir; Javaloyes, Miguel Angel
2016-01-01
We translate Penrose's singularity theorem to a Finsler spacetime. To that end, causal concepts in Lorentzian geometry are extended, including definitions and properties of focal points and trapped surfaces, with careful attention paid to the differences that arise in the Finslerian setting. This activity is supported by the programme 'Young leaders in research' 18942/JLI/13 by Fundación Séneca, Regional Agency for Science and Technology from the Region of Murcia, and by the World Premier International Research Center Initiative (WPI), MEXT, Japan.
Singularities in water waves and Rayleigh-Taylor instability
NASA Technical Reports Server (NTRS)
Tanveer, S.
1991-01-01
Singularities in inviscid two-dimensional finite-amplitude water waves and inviscid Rayleigh-Taylor instability are discussed. For the deep water gravity waves of permanent form, through a combination of analytical and numerical methods, results describing the precise form, number, and location of singularities in the unphysical domain as the wave height is increased are presented. It is shown how the information on the singularity in the unphysical region has the same form as for deep water waves. However, associated with such a singularity is a series of image singularities at increasing distances from the physical plane with possibly different behavior. Furthermore, for the Rayleigh-Taylor problem of motion of fluid over a vacuum and for the unsteady water wave problem, integro-differential equations valid in the unphysical region are derived, and how these equations can give information on the nature of singularities for arbitrary initial conditions is shown.
Are Singularities Integral to General Theory of Relativity?
NASA Astrophysics Data System (ADS)
Krori, K.; Dutta, S.
2011-11-01
Since the 1960s the general relativists have been deeply obsessed with the possibilities of GTR singularities - blackhole as well as cosmological singularities. Senovilla, for the first time, followed by others, showed that there are cylindrically symmetric cosmological space-times which are free of singularities. On the other hand, Krori et al. have presently shown that spherically symmetric cosmological space-times - which later reduce to FRW space-times may also be free of singularities. Besides, Mitra has in the mean-time come forward with some realistic calculations which seem to rule out the possibility of a blackhole singularity. So whether singularities are integral to GTR seems to come under a shadow.
Observer-dependent sign inversions of polarization singularities.
Freund, Isaac
2014-10-15
We describe observer-dependent sign inversions of the topological charges of vector field polarization singularities: C points (points of circular polarization), L points (points of linear polarization), and two virtually unknown singularities we call γ(C) and α(L) points. In all cases, the sign of the charge seen by an observer can change as she changes the direction from which she views the singularity. Analytic formulas are given for all C and all L point sign inversions.
Naked singularities in self-similar spherical gravitational collapse
Ori, A.; Piran, T.
1987-11-09
We present general-relativistic solutions of self-similar spherical collapse of an adiabatic perfect fluid. We show that if the equation of state is soft enough (GAMMA-1<<1), a naked singularity forms. The singularity resembles the shell-focusing naked singularities that arise in dust collapse. This solution increases significantly the range of matter fields that should be ruled out in order that the cosmic-censorship hypothesis will hold.
7 CFR 900.80 - Words in the singular form.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 8 2010-01-01 2010-01-01 false Words in the singular form. 900.80 Section 900.80....C. 608b(b) and 7 U.S.C. 608e Covering Fruits, Vegetables, and Nuts § 900.80 Words in the singular form. Words in this subpart in the singular form shall be deemed to import the plural, and vice...
Identify Foot of Continental Slope by singular spectrum and fractal singularity analysis
NASA Astrophysics Data System (ADS)
Li, Q.; Dehler, S.
2012-04-01
Identifying the Foot of Continental Slope (FOCS) plays a critical role in the determination of exclusive economic zone (EEZ) for coastal nations. The FOCS is defined by the Law of the Sea as the point of maximum change of the slope and it is mathematically equivalent to the point which has the maximum curvature value in its vicinity. However, curvature is the second derivative and the calculation of second derivative is a high pass and noise-prone filtering procedure. Therefore, identification of FOCS with curvature analysis methods is often uncertain and erroneous because observed bathymetry profiles or interpolated raster maps commonly include high frequency noises and artifacts, observation errors, and local sharp changes. Effective low-pass filtering methods and robust FOCS indicator algorithms are highly desirable. In this approach, nonlinear singular spectral filtering and singularity FOCS-indicator methods and software tools are developed to address this requirement. The normally used Fourier domain filtering methods decompose signals into Fourier space, composed of a fixed base that depends only on the acquisition interval of the signal; the signal is required to be stationary or at least weak stationary. In contrast to that requirement, the developed singular spectral filtering method constructs orthogonal basis functions dynamically according to different signals, and it does not require the signal to be stationary or weak stationary. Furthermore, singular spectrum analysis (SSA) can assist in designing suitable filters to carefully remove high-frequency local or noise components while reserving useful global and local components according to energy distribution. Geoscientific signals, including morphological ocean bathymetry data, often demonstrate fractal or multifractal properties. With proper definition of scales in the vicinity of a certain point and related measures, it is found that 1-dimensional bathymetry profiles and 2-dimensional raster maps
Timelike BKL singularities and chaos in AdS/CFT
NASA Astrophysics Data System (ADS)
Shaghoulian, Edgar; Wang, Huajia
2016-06-01
We study the nature of a family of curvature singularities which are precisely the timelike cousins of the spacelike singularities studied by Belinski, Khalatnikov, and Lifshitz (BKL). We show that the approach to the singularity can be modeled by a billiard ball problem on hyperbolic space, just as in the case of BKL. For pure gravity, generic chaotic behavior is retained in (3 + 1) dimensions, and we provide evidence that it disappears in higher dimensions. We speculate that such singularities, if occurring in AdS/CFT and of the chaotic variety, may be interpreted as (transient) chaotic renormalization group flows which exhibit features reminiscent of chaotic duality cascades.
LETTER TO THE EDITOR: Penrose limits and spacetime singularities
NASA Astrophysics Data System (ADS)
Blau, M.; Borunda, M.; O'Loughlin, M.; Papadopoulos, G.
2004-04-01
We give a covariant characterization of the Penrose plane wave limit: the plane wave profile matrix A(u) is the restriction of the null geodesic deviation matrix (curvature tensor) of the original spacetime metric to the null geodesic, evaluated in a comoving frame. We also consider the Penrose limits of spacetime singularities and show that for a large class of black hole, cosmological and null singularities (of Szekeres Iyer 'power-law type'), including those of the FRW and Schwarzschild metrics, the result is a singular homogeneous plane wave with profile A(u) ~ u-2, the scale invariance of the latter reflecting the power-law behaviour of the singularities.
Propagation of the Lissajous singularity dipole in free space
NASA Astrophysics Data System (ADS)
Chen, Haitao; Gao, Zenghui; Zou, Xuefang; Xiao, Xi; Wang, Fanhou; Yang, Huajun
2014-01-01
The propagation properties of a pair of Lissajous singularities with opposite singularity indexes called the Lissajous singularity dipole (LSD) in free space are studied analytically and illustrated numerically. It is shown that the motion, creation, annihilation and change in the degree of polarization of the LSD, and change in the shape of Lissajous figures take place by suitably varying the waist width, off-axis distance or propagation distance. In particular, the creation and shift to infinity of a single Lissajous singularity may appear. A comparison with the free-space propagation of an optical vortex dipole and a C-dipole is also made.
Plane wave gravitons, curvature singularities and string physics
Brooks, R. . Center for Theoretical Physics)
1991-03-21
This paper discusses bounded (compactifying) potentials arising from a conspiracy between plane wave graviton and dilaton condensates. So are string propagation and supersymmetry in spacetimes with curvature singularities.
Singular Isotropic Cosmologies and Bel-Robinson Energy
NASA Astrophysics Data System (ADS)
Cotsakis, Spiros; Klaoudatou, Ifigeneia
2006-11-01
We consider the problem of the nature and possible types of spacetime singularities that can form during the evolution of FRW universes in general relativity. We show that by using, in addition to the Hubble expansion rate and the scale factor, the Bel-Robinson energy of these universes we can consistently distinguish between the possible different types of singularities and arrive at a complete classification of the singularities that can occur in the isotropic case. We also use the Bel-Robinson energy to prove that known behaviours of exact flat isotropic universes with given singularities are generic in the sense that they hold true in every type of spatial geometry.
Quantum singularities in the FRW universe revisited
Letelier, Patricio S.; Pitelli, Joao Paulo M.
2010-08-15
The components of the Riemann tensor in the tetrad basis are quantized and, through the Einstein equation, we find the local expectation value in the ontological interpretation of quantum mechanics of the energy density and pressure of a perfect fluid with equation of state p=(1/3){rho} in the flat Friedmann-Robertson-Walker quantum cosmological model. The quantum behavior of the equation of state and energy conditions are then studied, and it is shown that the energy conditions are violated since the singularity is removed with the introduction of quantum cosmology, but in the classical limit both the equation of state and the energy conditions behave as in the classical model. We also calculate the expectation value of the scale factor for several wave packets in the many-worlds interpretation in order to show the independence of the nonsingular character of the quantum cosmological model with respect to the wave packet representing the wave function of the Universe. It is also shown that, with the introduction of nonnormalizable wave packets, solutions of the Wheeler-DeWitt equation, the singular character of the scale factor, can be recovered in the ontological interpretation.
Aircraft Range Optimization Using Singular Perturbations
NASA Technical Reports Server (NTRS)
Oconnor, Joseph Taffe
1973-01-01
An approximate analytic solution is developed for the problem of maximizing the range of an aircraft for a fixed end state. The problem is formulated as a singular perturbation and solved by matched inner and outer asymptotic expansions and the minimum principle of Pontryagin. Cruise in the stratosphere, and on transition to and from cruise at constant Mach number are discussed. The state vector includes altitude, flight path angle, and mass. Specific fuel consumption becomes a linear function of power approximating that of the cruise values. Cruise represents the outer solution; altitude and flight path angle are constants, and only mass changes. Transitions between cruise and the specified initial and final conditions correspond to the inner solutions. The mass is constant and altitude and velocity vary. A solution is developed which is valid for cruise but which is not for the initial and final conditions. Transforming of the independent variable near the initial and final conditions result in solutions which are valid for the two inner solutions but not for cruise. The inner solutions can not be obtained without simplifying the state equations. The singular perturbation approach overcomes this difficulty. A quadratic approximation of the state equations is made. The resulting problem is solved analytically, and the two inner solutions are matched to the outer solution.
On singular fibres in F-theory
NASA Astrophysics Data System (ADS)
Braun, Andreas P.; Watari, Taizan
2013-07-01
In this paper, we propose a connection between the field theory local model (Katz-Vafa field theory) and the type of singular fibre in flat crepant resolutions of elliptic Calabi-Yau fourfolds, a class of fourfolds considered by Esole and Yau. We review the analysis of degenerate fibres for models with gauge groups SU(5) and SO(10) in detail, and observe that the naively expected fibre type is realized if and only if the Higgs vev in the field theory local model is unramified. To test this idea, we implement a linear (unramified) Higgs vev for the " E 6" Yukawa point in a model with gauge group SU(5) and verify that this indeed leads to a fibre of Kodaira type IV*. Based on this observation, we argue i) that the singular fibre types appearing in the fourfolds studied by Esole-Yau are not puzzling at all, (so that this class of fourfolds does not have to be excluded from the candidate of input data of some yet-unknown formulation of F-theory) and ii) that such fourfold geometries also contain more information than just the eigenvalues of the Higgs field vev configuration in the field theory local models.
Metric dimensional reduction at singularities with implications to Quantum Gravity
Stoica, Ovidiu Cristinel
2014-08-15
A series of old and recent theoretical observations suggests that the quantization of gravity would be feasible, and some problems of Quantum Field Theory would go away if, somehow, the spacetime would undergo a dimensional reduction at high energy scales. But an identification of the deep mechanism causing this dimensional reduction would still be desirable. The main contribution of this article is to show that dimensional reduction effects are due to General Relativity at singularities, and do not need to be postulated ad-hoc. Recent advances in understanding the geometry of singularities do not require modification of General Relativity, being just non-singular extensions of its mathematics to the limit cases. They turn out to work fine for some known types of cosmological singularities (black holes and FLRW Big-Bang), allowing a choice of the fundamental geometric invariants and physical quantities which remain regular. The resulting equations are equivalent to the standard ones outside the singularities. One consequence of this mathematical approach to the singularities in General Relativity is a special, (geo)metric type of dimensional reduction: at singularities, the metric tensor becomes degenerate in certain spacetime directions, and some properties of the fields become independent of those directions. Effectively, it is like one or more dimensions of spacetime just vanish at singularities. This suggests that it is worth exploring the possibility that the geometry of singularities leads naturally to the spontaneous dimensional reduction needed by Quantum Gravity. - Highlights: • The singularities we introduce are described by finite geometric/physical objects. • Our singularities are accompanied by dimensional reduction effects. • They affect the metric, the measure, the topology, the gravitational DOF (Weyl = 0). • Effects proposed in other approaches to Quantum Gravity are obtained naturally. • The geometric dimensional reduction obtained
Singular inflation from Born-Infeld-f(R) gravity
NASA Astrophysics Data System (ADS)
Elizalde, Emilio; Makarenko, Andrey N.
2016-07-01
Accelerating dynamics from Born-Infeld-f(R) gravity are studied in a simplified conformal approach without matter. Explicit unification of inflation with late-time acceleration is realized within this singular inflation approach, which is similar to Odintsov-Oikonomou singular f(R) inflation. Our model turns out to be consistent with the latest release of Planck data.
Two Approaches of Studying Singularity of Projective Conics
ERIC Educational Resources Information Center
Broyles, Chris; Muller, Lars; Tikoo, Mohan; Wang, Haohao
2010-01-01
The singularity of a projective conic can be determined via the associated matrix to the implicit equation of the projective conic. In this expository article, we will first derive a known result for determining the singularity of a projective conic via the associated matrix. Then we will introduce the concepts of [mu]-basis of the parametric…
Singularities in the Origin and Evolution of Life
Duve, Christian de
2003-11-19
The history of life is landmarked by a large number of remarkable singularities. The single ancestry of all living beings, the universal genetic code, and the monophyletic origin of eukaryotes are typical examples, but there are many others. The mechanisms responsible for these singularities will be discussed.
Twisting singular solutions of Betheʼs equations
NASA Astrophysics Data System (ADS)
Nepomechie, Rafael I.; Wang, Chunguang
2014-12-01
The Bethe equations for the periodic XXX and XXZ spin chains admit singular solutions, for which the corresponding eigenvalues and eigenvectors are ill-defined. We use a twist regularization to derive conditions for such singular solutions to be physical, in which case they correspond to genuine eigenvalues and eigenvectors of the Hamiltonian.
Singular accelerated evolution in massive F (R ) bigravity
NASA Astrophysics Data System (ADS)
Nojiri, S.; Odintsov, S. D.; Oikonomou, V. K.
2015-12-01
The possibility to have singular accelerated evolution in the context of F (R ) bimetric gravity is investigated. Particularly, we study two singular models of cosmological evolution, one of which is a singular modified version of the Starobinsky R2 inflation model. As we demonstrate, for both models in some cases, the slow-roll parameters become singular at the Type IV singularity, a fact that we interpret as a dynamical instability of the theory under study. This dynamical instability may be an indicator of a graceful exit from inflation, and we thoroughly discuss this scenario and the interpretation of the singular slow-roll parameters. Furthermore, it is demonstrated that for some versions of F (R ) bigravity, singular inflation is realized in a consistent way so that inflationary indices are compatible with Planck data. Moreover, we study the late-time behavior of the two singular models, and we show that the unified description of early- and late-time acceleration can be achieved in the context of bimetric F (R ) gravity.
Generalised hyperbolicity in spacetimes with string-like singularities
NASA Astrophysics Data System (ADS)
Sanchez Sanchez, Yafet; Vickers, James A.
2016-10-01
In this paper we present well-posedness results for H 1 solutions of the wave equation for spacetimes that contain string-like singularities. These results extend a framework in which one characterises gravitational singularities as obstruction to the dynamics of test fields rather than point particles. In particular, we discuss spacetimes with cosmic strings.
A numerical method for solving singular De`s
Mahaver, W.T.
1996-12-31
A numerical method is developed for solving singular differential equations using steepest descent based on weighted Sobolev gradients. The method is demonstrated on a variety of first and second order problems, including linear constrained, unconstrained, and partially constrained first order problems, a nonlinear first order problem with irregular singularity, and two second order variational problems.
7 CFR 1200.1 - Words in the singular form.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 7 Agriculture 10 2010-01-01 2010-01-01 false Words in the singular form. 1200.1 Section 1200.1 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING... Governing Proceedings To Formulate and Amend an Order § 1200.1 Words in the singular form. Words in...
Kirchhof, Paulus; Lip, Gregory Y.H.; Van Gelder, Isabelle C.; Bax, Jeroen; Hylek, Elaine; Kaab, Stefan; Schotten, Ulrich; Wegscheider, Karl; Boriani, Giuseppe; Brandes, Axel; Ezekowitz, Michael; Diener, Hans; Haegeli, Laurent; Heidbuchel, Hein; Lane, Deirdre; Mont, Luis; Willems, Stephan; Dorian, Paul; Aunes-Jansson, Maria; Blomstrom-Lundqvist, Carina; Borentain, Maria; Breitenstein, Stefanie; Brueckmann, Martina; Cater, Nilo; Clemens, Andreas; Dobrev, Dobromir; Dubner, Sergio; Edvardsson, Nils G.; Friberg, Leif; Goette, Andreas; Gulizia, Michele; Hatala, Robert; Horwood, Jenny; Szumowski, Lukas; Kappenberger, Lukas; Kautzner, Josef; Leute, Angelika; Lobban, Trudie; Meyer, Ralf; Millerhagen, Jay; Morgan, John; Muenzel, Felix; Nabauer, Michael; Baertels, Christoph; Oeff, Michael; Paar, Dieter; Polifka, Juergen; Ravens, Ursula; Rosin, Ludger; Stegink, W.; Steinbeck, Gerhard; Vardas, Panos; Vincent, Alphons; Walter, Maureen; Breithardt, Günter; Camm, A. John
2012-01-01
While management of atrial fibrillation (AF) patients is improved by guideline-conform application of anticoagulant therapy, rate control, rhythm control, and therapy of accompanying heart disease, the morbidity and mortality associated with AF remain unacceptably high. This paper describes the proceedings of the 3rd Atrial Fibrillation NETwork (AFNET)/European Heart Rhythm Association (EHRA) consensus conference that convened over 60 scientists and representatives from industry to jointly discuss emerging therapeutic and diagnostic improvements to achieve better management of AF patients. The paper covers four chapters: (i) risk factors and risk markers for AF; (ii) pathophysiological classification of AF; (iii) relevance of monitored AF duration for AF-related outcomes; and (iv) perspectives and needs for implementing better antithrombotic therapy. Relevant published literature for each section is covered, and suggestions for the improvement of management in each area are put forward. Combined, the propositions formulate a perspective to implement comprehensive management in AF. PMID:21791573
Kirchhof, Paulus; Lip, Gregory Y H; Van Gelder, Isabelle C; Bax, Jeroen; Hylek, Elaine; Kaab, Stefan; Schotten, Ulrich; Wegscheider, Karl; Boriani, Giuseppe; Brandes, Axel; Ezekowitz, Michael; Diener, Hans; Haegeli, Laurent; Heidbuchel, Hein; Lane, Deirdre; Mont, Luis; Willems, Stephan; Dorian, Paul; Aunes-Jansson, Maria; Blomstrom-Lundqvist, Carina; Borentain, Maria; Breitenstein, Stefanie; Brueckmann, Martina; Cater, Nilo; Clemens, Andreas; Dobrev, Dobromir; Dubner, Sergio; Edvardsson, Nils G; Friberg, Leif; Goette, Andreas; Gulizia, Michele; Hatala, Robert; Horwood, Jenny; Szumowski, Lukas; Kappenberger, Lukas; Kautzner, Josef; Leute, Angelika; Lobban, Trudie; Meyer, Ralf; Millerhagen, Jay; Morgan, John; Muenzel, Felix; Nabauer, Michael; Baertels, Christoph; Oeff, Michael; Paar, Dieter; Polifka, Juergen; Ravens, Ursula; Rosin, Ludger; Stegink, W; Steinbeck, Gerhard; Vardas, Panos; Vincent, Alphons; Walter, Maureen; Breithardt, Günter; Camm, A John
2012-01-01
While management of atrial fibrillation (AF) patients is improved by guideline-conform application of anticoagulant therapy, rate control, rhythm control, and therapy of accompanying heart disease, the morbidity and mortality associated with AF remain unacceptably high. This paper describes the proceedings of the 3rd Atrial Fibrillation NETwork (AFNET)/European Heart Rhythm Association (EHRA) consensus conference that convened over 60 scientists and representatives from industry to jointly discuss emerging therapeutic and diagnostic improvements to achieve better management of AF patients. The paper covers four chapters: (i) risk factors and risk markers for AF; (ii) pathophysiological classification of AF; (iii) relevance of monitored AF duration for AF-related outcomes; and (iv) perspectives and needs for implementing better antithrombotic therapy. Relevant published literature for each section is covered, and suggestions for the improvement of management in each area are put forward. Combined, the propositions formulate a perspective to implement comprehensive management in AF. PMID:21791573
Spacetime singularity resolution in Snyder noncommutative space
NASA Astrophysics Data System (ADS)
Gorji, M. A.; Nozari, K.; Vakili, B.
2014-04-01
Inspired by quantum gravity proposals, we construct a deformed phase space which supports the UV and IR cutoffs. We show that the Liouville theorem is satisfied in the deformed phase space which allows us to formulate the thermodynamics of the early universe in the semiclassical regime. Applying the proposed method to the Snyder noncommutative space, we find a temperature dependent equation of state which opens a new window for the natural realization of inflation as a phase transition from the quantum gravity regime to the standard radiation dominated era. Also, we obtain finite energy and entropy densities for the Universe when at least the weak energy condition is satisfied. We show that there is a minimum size for the Universe which is proportional to the Planck length and consequently the big bang singularity is removed.
String wave function across a Kasner singularity
Copeland, Edmund J.; Niz, Gustavo; Turok, Neil
2010-06-15
A collision of orbifold planes in 11 dimensions has been proposed as an explanation of the hot big bang. When the two planes are close to each other, the winding membranes become the lightest modes of the theory, and can be effectively described in terms of fundamental strings in a ten-dimensional background. Near the brane collision, the 11-dimensional metric is a Euclidean space times a 1+1-dimensional Milne universe. However, one may expect small perturbations to lead into a more general Kasner background. In this paper we extend the previous classical analysis of winding membranes to Kasner backgrounds, and using the Hamiltonian equations, solve for the wave function of loops with circular symmetry. The evolution across the singularity is regular, and explained in terms of the excitement of higher oscillation modes. We also show there is finite particle production and unitarity is preserved.
Autoregressive models of singular spectral matrices☆
Anderson, Brian D.O.; Deistler, Manfred; Chen, Weitian; Filler, Alexander
2012-01-01
This paper deals with autoregressive (AR) models of singular spectra, whose corresponding transfer function matrices can be expressed in a stable AR matrix fraction description D−1(q)B with B a tall constant matrix of full column rank and with the determinantal zeros of D(q) all stable, i.e. in |q|>1,q∈C. To obtain a parsimonious AR model, a canonical form is derived and a number of advantageous properties are demonstrated. First, the maximum lag of the canonical AR model is shown to be minimal in the equivalence class of AR models of the same transfer function matrix. Second, the canonical form model is shown to display a nesting property under natural conditions. Finally, an upper bound is provided for the total number of real parameters in the obtained canonical AR model, which demonstrates that the total number of real parameters grows linearly with the number of rows in W(q). PMID:23483210
Singular perturbations in the state regulator problem
NASA Technical Reports Server (NTRS)
Ardema, M. D.
1972-01-01
Most of the results of singular perturbation theory have been concerned with initial value problems whereas optimal control problems are of two-point boundary value type. The portions of this theory applicable to the open loop state regulator problem are reviewed. For obtaining approximate solutions to the state regulator problem the method of matched asymptotic expansions is employed. This method has been developed in connection with certain fluid mechanics problems and is applicable to nonlinear as well as linear problems. It has been found in the past to be advantageous not to formulate this method generally but to apply it to each individual problem and this approach is adopted here. A general recipe for the method is given and its application is illustrated by using the method to obtain an approximate solution to a simple, specific state regulator problem.
Stress Singularities in Swelling Soft Solids
NASA Astrophysics Data System (ADS)
Goriely, Alain; Weickenmeier, Johannes; Kuhl, Ellen
2016-09-01
When a swelling soft solid is rigidly constrained on all sides except for a circular opening, it will bulge out to expand as observed during decompressive craniectomy, a surgical procedure used to reduce stresses in swollen brains. While the elastic energy of the solid decreases throughout this process, large stresses develop close to the opening. At the point of contact, the stresses exhibit a singularity similar to the ones found in the classic punch indentation problem. Here, we study the stresses generated by swelling and the evolution of the bulging shape associated with this process. We also consider the possibility of damage triggered by zones of either high shear stresses or high fiber stretches.
Singular values, nematic disclinations, and emergent biaxiality.
Čopar, Simon; Dennis, Mark R; Kamien, Randall D; Žumer, Slobodan
2013-05-01
Both uniaxial and biaxial nematic liquid crystals are defined by orientational ordering of their building blocks. While uniaxial nematics only orient the long molecular axis, biaxial order implies local order along three axes. As the natural degree of biaxiality and the associated frame that can be extracted from the tensorial description of the nematic order vanishes in the uniaxial phase, we extend the nematic director to a full biaxial frame by making use of a singular value decomposition of the gradient of the director field instead. The degrees of freedom are unveiled in the form of quasidefects and the similarities and differences between the uniaxial and biaxial phase are analyzed by applying the algebraic rules of the quaternion group to the uniaxial phase. PMID:23767474
Dual Vector Spaces and Physical Singularities
NASA Astrophysics Data System (ADS)
Rowlands, Peter
Though we often refer to 3-D vector space as constructed from points, there is no mechanism from within its definition for doing this. In particular, space, on its own, cannot accommodate the singularities that we call fundamental particles. This requires a commutative combination of space as we know it with another 3-D vector space, which is dual to the first (in a physical sense). The combination of the two spaces generates a nilpotent quantum mechanics/quantum field theory, which incorporates exact supersymmetry and ultimately removes the anomalies due to self-interaction. Among the many natural consequences of the dual space formalism are half-integral spin for fermions, zitterbewegung, Berry phase and a zero norm Berwald-Moor metric for fermionic states.
Helicity and singular structures in fluid dynamics
Moffatt, H. Keith
2014-01-01
Helicity is, like energy, a quadratic invariant of the Euler equations of ideal fluid flow, although, unlike energy, it is not sign definite. In physical terms, it represents the degree of linkage of the vortex lines of a flow, conserved when conditions are such that these vortex lines are frozen in the fluid. Some basic properties of helicity are reviewed, with particular reference to (i) its crucial role in the dynamo excitation of magnetic fields in cosmic systems; (ii) its bearing on the existence of Euler flows of arbitrarily complex streamline topology; (iii) the constraining role of the analogous magnetic helicity in the determination of stable knotted minimum-energy magnetostatic structures; and (iv) its role in depleting nonlinearity in the Navier-Stokes equations, with implications for the coherent structures and energy cascade of turbulence. In a final section, some singular phenomena in low Reynolds number flows are briefly described. PMID:24520175
Infinitely many singular interactions on noncompact manifolds
Kaynak, Burak Tevfik Turgut, O. Teoman
2015-05-15
We show that the ground state energy is bounded from below when there are infinitely many attractive delta function potentials placed in arbitrary locations, while all being separated at least by a minimum distance, on two dimensional non-compact manifold. To facilitate the reading of the paper, we first present the arguments in the setting of Cartan–Hadamard manifolds and then subsequently discuss the general case. For this purpose, we employ the heat kernel techniques as well as some comparison theorems of Riemannian geometry, thus generalizing the arguments in the flat case following the approach presented in Albeverio et al. (2004). - Highlights: • Schrödinger-operator for infinitely many singular interactions on noncompact manifolds. • Proof of the finiteness of the ground-state energy.
ANALYTICAL SOLUTIONS OF SINGULAR ISOTHERMAL QUADRUPOLE LENS
Chu Zhe; Lin, W. P.; Yang Xiaofeng E-mail: linwp@shao.ac.cn
2013-06-20
Using an analytical method, we study the singular isothermal quadrupole (SIQ) lens system, which is the simplest lens model that can produce four images. In this case, the radial mass distribution is in accord with the profile of the singular isothermal sphere lens, and the tangential distribution is given by adding a quadrupole on the monopole component. The basic properties of the SIQ lens have been studied in this Letter, including the deflection potential, deflection angle, magnification, critical curve, caustic, pseudo-caustic, and transition locus. Analytical solutions of the image positions and magnifications for the source on axes are derived. We find that naked cusps will appear when the relative intensity k of quadrupole to monopole is larger than 0.6. According to the magnification invariant theory of the SIQ lens, the sum of the signed magnifications of the four images should be equal to unity, as found by Dalal. However, if a source lies in the naked cusp, the summed magnification of the left three images is smaller than the invariant 1. With this simple lens system, we study the situations where a point source infinitely approaches a cusp or a fold. The sum of the magnifications of the cusp image triplet is usually not equal to 0, and it is usually positive for major cusps while negative for minor cusps. Similarly, the sum of magnifications of the fold image pair is usually not equal to 0 either. Nevertheless, the cusp and fold relations are still equal to 0 in that the sum values are divided by infinite absolute magnifications by definition.
Kampmeyer, Daniela; Matthes, Jan; Herzig, Stefan
2015-05-01
Multiple-choice-questions are common in medical examinations, but guessing biases assessment results. Confidence-based-testing (CBT) integrates indicated confidence levels. It has been suggested that correctness of and confidence in an answer together indicate knowledge levels thus determining the quality of a resulting decision. We used a CBT approach to investigate whether decision quality improves during undergraduate medical education. 3rd- and 5th-year students attended formative multiple-choice exams on pharmacological issues. Students were asked to indicate their confidence in a given answer. Correctness of answers was scored binary (1-correct; 0-wrong) and confidence levels were transformed to an ordinal scale (guess: 0; rather unsure: 0.33; rather sure: 0.66; very sure: 1). 5th-year students gave more correct answers (73 ± 16 vs. 49 ± 13 %, p < 0.05) and were on average more confident regarding the correctness of their answers (0.61 ± 0.18 vs. 0.46 ± 0.13, p < 0.05). Correlation of these parameters was stronger for 5th-year students (r = 0.81 vs. r = 0.52), but agreement of confidence and correctness ('centration') was lower. By combining the Bland-and-Altman approach with categories of decision-quality we found that 5th-year students were more likely to be 'well-informed' (41 vs. 5 %), while more 3rd-students were 'uninformed' (24 vs. 76 %). Despite a good correlation of exam results and confidence in given answers increased knowledge might be accompanied by a more critical view at the own abilities. Combining the statistical Bland-and-Altman analysis with a theoretical approach to decision-quality, more advanced students are expected to apply correct beliefs, while their younger fellows are rather at risk to hesitate or to act amiss.
Willenbacher, Ella; Weger, Roman; Rochau, Ursula; Siebert, Uwe; Willenbacher, Wolfgang
2016-01-01
Objective Clinical trials demonstrate improving survival in patients with multiple myeloma (MM) after treatment. However, it is unclear whether increased survival translates to a similar benefit in a real world setting. Methods We analyzed the overall survival of 347 multiple myeloma patients in Austria by means of a national registry (AMR), focused on results from 3rd and later lines of therapy. This benchmark was chosen to define a baseline prior to the broad application of upcoming 2nd generation drugs (carfilzomib, pomalidomide). Results Projected 10 years survival for patients with MM in Austria is estimated to be 56% in patients diagnosed in between the years 2011–2014, 21% in patients with a diagnosis made between 2000–2005, and 39% in those with a diagnosis made between 2006–2010). For the same intervals a significant increase in the use of both bortezomib, lenalidomide and thalidomide—so called IMiDs (from 2005 onwards) and their simultaneous use in combination therapies (from 2010 onwards) could be shown. The use of autologous transplantation (ASCT) remained more or less constant at ~ 35% of patients in the 1st line setting over the whole period, comparing well to international practice patterns, while the use of 2nd line ASCT increased from 5.5% to 18.7% of patients. Patients in 3rd or later line treatment (n = 105), showed that even in relapsed and refractory disease median survival was 27 months with a considerable proportion of long-term survivors (~20%). Conclusion & Perspective With the expected emergence of additional active anti-myeloma compounds, we aim to assess survival in patients with relapsed and refractory MM. PMID:26937956
Particle creation by naked singularities in higher dimensions
Miyamoto, Umpei; Nemoto, Hiroya; Shimano, Masahiro
2011-04-15
Recently, the possibility was pointed out by one of the present authors and his collaborators that an effective naked singularity referred to as ''a visible border of spacetime'' is generated by high-energy particle collision in the context of large extra dimensions or TeV-scale gravity. In this paper, we investigate the particle creation by a naked singularity in general dimensions, while adopting a model in which a marginally naked singularity forms in the collapse of a homothetic lightlike pressureless fluid. We find that the spectrum deviates from that of Hawking radiation due to scattering near the singularity but can be recast in quasithermal form. The temperature is always higher than that of Hawking radiation of a same-mass black hole, and can be arbitrarily high depending on a parameter in the model. This implies that, in principle, the naked singularity may be distinguished from a black hole in collider experiments.
Three-dimensional isolated quotient singularities in odd characteristic
NASA Astrophysics Data System (ADS)
Stepanov, D. A.
2016-06-01
Let a finite group G act linearly on a finite-dimensional vector space V over an algebraically closed field k of characteristic p>2. Suppose that the quotient space V/G has an isolated singularity only. The isolated singularities of the form V/G are completely classified in the case when p does not divide the order of G, and their classification reduces to Vincent's classification of isolated quotient singularities over C. In the present paper we show that, if \\dim V=3, then the classification of isolated quotient singularities reduces to Vincent's classification in the modular case as well (when p divides \\vert G\\vert). Some remarks on quotient singularities in other dimensions and in even characteristic are also given. Bibliography: 14 titles.
Cusp singularities in f(R) gravity: pros and cons
Chen, Pisin; Yeom, Dong-han
2015-10-01
We investigate cusp singularities in f(R) gravity, especially for Starobinsky and Hu-Sawicki dark energy models. We illustrate that, by using double-null numerical simulations, a cusp singularity can be triggered by gravitational collapses. This singularity can be cured by adding a quadratic term, but this causes a Ricci scalar bump that can be observed by an observer outside the event horizon. Comparing with cosmological parameters, it seems that it would be difficult to see super-Planckian effects by astrophysical experiments. On the other hand, at once there exists a cusp singularity, it can be a mechanism to realize a horizon scale curvature singularity that can be interpreted by a firewall.
Sharp bounds for singular values of fractional integral operators
NASA Astrophysics Data System (ADS)
Burman, Prabir
2007-03-01
From the results of Dostanic [M.R. Dostanic, Asymptotic behavior of the singular values of fractional integral operators, J. Math. Anal. Appl. 175 (1993) 380-391] and Vu and Gorenflo [Kim Tuan Vu, R. Gorenflo, Singular values of fractional and Volterra integral operators, in: Inverse Problems and Applications to Geophysics, Industry, Medicine and Technology, Ho Chi Minh City, 1995, Ho Chi Minh City Math. Soc., Ho Chi Minh City, 1995, pp. 174-185] it is known that the jth singular value of the fractional integral operator of order [alpha]>0 is approximately ([pi]j)-[alpha] for all large j. In this note we refine this result by obtaining sharp bounds for the singular values and use these bounds to show that the jth singular value is ([pi]j)-[alpha][1+O(j-1)].
Singular Lorentz-violating Lagrangians and associated Finsler structures
NASA Astrophysics Data System (ADS)
Colladay, Don; McDonald, Patrick
2015-10-01
Several Lagrangians associated with classical limits of Lorentz-violating fermions in the standard model extension (SME) have been shown to yield Finsler functions when the theory is expressed in Euclidean space. When spin couplings are present, the Lagrangian can develop singularities that obstruct the construction of a globally defined Legendre transformation, leading to singular Finsler spaces. A specific sector of the SME where such problems arise is studied. It is found that the singular behavior can be eliminated by an appropriate lifting of the problem to an associated algebraic variety. This provides a smooth classical model for the singular problem. In Euclidean space, the procedure involves combining two related singular Finsler functions into a single smooth function with a semi-positive-definite quadratic form defined on a desingularized variety.
NASA Astrophysics Data System (ADS)
Matveenko, V. P.; Fedorov, A. Yu.; Shardakov, I. N.
2016-01-01
The results of analytical and numerical investigations on estimating the character of the singularity of stresses in a vicinity of different variants of special points of the 2D elastic solids made of functionally graded materials (FGMs) are presented. The variant of construction by analytical methods in the polar system of coordinates is considered for eigensolutions in the flat wedges made of the FGM, the elastic properties of which are represented as power series in terms of the radial coordinate.
Ullmann, E; Barthel, A; Licinio, J; Petrowski, K; Bornstein, S R; Strauß, B
2013-03-12
The mental health status of persons with Jewish background living in Germany is discussed with special regard to social exclusion like anti-Semitism and overprotective parental rearing behavior, as a transmissional factor of the KZ-Syndrome. These stressors are considered in the context of a higher risk for depression/fear and psychosomatic disorders and also abnormal cortisol levels. The present sample (N=89) is derived from the Jewish population currently living in the German region of Saxony aged between 17-36 years that emigrated from the post-Soviet-Union areas. The mean age was 22.9 years. Two questionnaires to detect psychosomatic symptoms (Giessen complaint list (GBB)-24, hospital anxiety and depression scale) and one questionnaire addressing parental rearing behavior (FEE) were employed. Comparisons were drawn with normative data from the literature about the German residential population. In addition, questions were asked concerning the experience of anti-Semitism in Germany and in the post-Soviet-Union areas. A higher prevalence of depression/fear (10.3% versus 18.2%) and psychosomatic symptoms (M=14.03 versus 17.8; t=2.42; P<0.05) was observed in Jewish migrants to Germany as compared with non-Jewish German residents. Furthermore, anti-Semitic experiences in Germany correlated positively with depression (r=0.293; P<0.01) and fear (r=0.254; P<0.05). The anti-Semitic experiences in the post-Soviet-Union areas also correlated positively with limb pain (r=0.41, P<0.01), fatigue symptoms (r=0.296, P<0.01) and psychocardial symptoms (r=0.219, P<0.05). It was also confirmed that the male respondents recalled a controlling and overprotecting maternal rearing behavior more frequently than the German standard random sample (M=15.39 versus 18.6; t=2.68; P<0.01). The latter also correlated significantly positive with epigastric pain (r=0.349; P<0.01). The present results show that depression, fear and psychosomatic problems are common in Jewish residents with a
Ullmann, E; Barthel, A; Licinio, J; Petrowski, K; Bornstein, S R; Strauß, B
2013-01-01
The mental health status of persons with Jewish background living in Germany is discussed with special regard to social exclusion like anti-Semitism and overprotective parental rearing behavior, as a transmissional factor of the KZ-Syndrome. These stressors are considered in the context of a higher risk for depression/fear and psychosomatic disorders and also abnormal cortisol levels. The present sample (N=89) is derived from the Jewish population currently living in the German region of Saxony aged between 17–36 years that emigrated from the post-Soviet-Union areas. The mean age was 22.9 years. Two questionnaires to detect psychosomatic symptoms (Giessen complaint list (GBB)-24, hospital anxiety and depression scale) and one questionnaire addressing parental rearing behavior (FEE) were employed. Comparisons were drawn with normative data from the literature about the German residential population. In addition, questions were asked concerning the experience of anti-Semitism in Germany and in the post-Soviet-Union areas. A higher prevalence of depression/fear (10.3% versus 18.2%) and psychosomatic symptoms (M=14.03 versus 17.8; t=2.42; P<0.05) was observed in Jewish migrants to Germany as compared with non-Jewish German residents. Furthermore, anti-Semitic experiences in Germany correlated positively with depression (r=0.293; P<0.01) and fear (r=0.254; P<0.05). The anti-Semitic experiences in the post-Soviet-Union areas also correlated positively with limb pain (r=0.41, P<0.01), fatigue symptoms (r=0.296, P<0.01) and psychocardial symptoms (r=0.219, P<0.05). It was also confirmed that the male respondents recalled a controlling and overprotecting maternal rearing behavior more frequently than the German standard random sample (M=15.39 versus 18.6; t=2.68; P<0.01). The latter also correlated significantly positive with epigastric pain (r=0.349; P<0.01). The present results show that depression, fear and psychosomatic problems are common in Jewish residents with a
Ullmann, E; Barthel, A; Licinio, J; Petrowski, K; Bornstein, S R; Strauß, B
2013-01-01
The mental health status of persons with Jewish background living in Germany is discussed with special regard to social exclusion like anti-Semitism and overprotective parental rearing behavior, as a transmissional factor of the KZ-Syndrome. These stressors are considered in the context of a higher risk for depression/fear and psychosomatic disorders and also abnormal cortisol levels. The present sample (N=89) is derived from the Jewish population currently living in the German region of Saxony aged between 17-36 years that emigrated from the post-Soviet-Union areas. The mean age was 22.9 years. Two questionnaires to detect psychosomatic symptoms (Giessen complaint list (GBB)-24, hospital anxiety and depression scale) and one questionnaire addressing parental rearing behavior (FEE) were employed. Comparisons were drawn with normative data from the literature about the German residential population. In addition, questions were asked concerning the experience of anti-Semitism in Germany and in the post-Soviet-Union areas. A higher prevalence of depression/fear (10.3% versus 18.2%) and psychosomatic symptoms (M=14.03 versus 17.8; t=2.42; P<0.05) was observed in Jewish migrants to Germany as compared with non-Jewish German residents. Furthermore, anti-Semitic experiences in Germany correlated positively with depression (r=0.293; P<0.01) and fear (r=0.254; P<0.05). The anti-Semitic experiences in the post-Soviet-Union areas also correlated positively with limb pain (r=0.41, P<0.01), fatigue symptoms (r=0.296, P<0.01) and psychocardial symptoms (r=0.219, P<0.05). It was also confirmed that the male respondents recalled a controlling and overprotecting maternal rearing behavior more frequently than the German standard random sample (M=15.39 versus 18.6; t=2.68; P<0.01). The latter also correlated significantly positive with epigastric pain (r=0.349; P<0.01). The present results show that depression, fear and psychosomatic problems are common in Jewish residents with a
Future singularity avoidance in phantom dark energy models
Haro, Jaume de
2012-07-01
Different approaches to quantum cosmology are studied in order to deal with the future singularity avoidance problem. Our results show that these future singularities will persist but could take different forms. As an example we have studied the big rip which appear when one considers the state equation P = ωρ with ω < −1, showing that it does not disappear in modified gravity. On the other hand, it is well-known that quantum geometric effects (holonomy corrections) in loop quantum cosmology introduce a quadratic modification, namely proportional to ρ{sup 2}, in Friedmann's equation that replace the big rip by a non-singular bounce. However this modified Friedmann equation could have been obtained in an inconsistent way, what means that the obtained results from this equation, in particular singularity avoidance, would be incorrect. In fact, we will show that instead of a non-singular bounce, the big rip singularity would be replaced, in loop quantum cosmology, by other kind of singularity.
Singular Dimensions of theN= 2 Superconformal Algebras. I
NASA Astrophysics Data System (ADS)
Dörrzapf, Matthias; Gato-Rivera, Beatriz
Verma modules of superconfomal algebras can have singular vector spaces with dimensions greater than 1. Following a method developed for the Virasoro algebra by Kent, we introduce the concept of adapted orderings on superconformal algebras. We prove several general results on the ordering kernels associated to the adapted orderings and show that the size of an ordering kernel implies an upper limit for the dimension of a singular vector space. We apply this method to the topological N= 2 algebra and obtain the maximal dimensions of the singular vector spaces in the topological Verma modules: 0, 1, 2 or 3 depending on the type of Verma module and the type of singular vector. As a consequence we prove the conjecture of Gato-Rivera and Rosado on the possible existing types of topological singular vectors (4 in chiral Verma modules and 29 in complete Verma modules). Interestingly, we have found two-dimensional spaces of singular vectors at level 1. Finally, by using the topological twists and the spectral flows, we also obtain the maximal dimensions of the singular vector spaces for the Neveu-Schwarz N= 2 algebra (0, 1 or 2) and for the Ramond N= 2 algebra (0, 1, 2 or 3).
Generating Hyperbolic Singularities in Semitoric Systems Via Hopf Bifurcations
NASA Astrophysics Data System (ADS)
Dullin, Holger R.; Pelayo, Álvaro
2016-06-01
Let (M,Ω ) be a connected symplectic 4-manifold and let F=(J,H) :M→ {R}^2 be a completely integrable system on M with only non-degenerate singularities. Assume that F does not have singularities with hyperbolic blocks and that p_1,ldots ,p_n are the focus-focus singularities of F. For each subset S={i_1,ldots ,i_j}, we will show how to modify F locally around any p_i, i in S, in order to create a new integrable system widetilde{F}=(J, widetilde{H}) :M → {R}^2 such that its classical spectrum widetilde{F}(M) contains j smooth curves of singular values corresponding to non-degenerate transversally hyperbolic singularities of widetilde{F}. Moreover the focus-focus singularities of widetilde{F} are precisely p_i, i in {1,ldots ,n} setminus S. The proof is based on Eliasson's linearization theorem for non-degenerate singularities, and properties of the Hamiltonian Hopf bifurcation.
Boundary singularities produced by the motion of soap films.
Goldstein, Raymond E; McTavish, James; Moffatt, H Keith; Pesci, Adriana I
2014-06-10
Recent work has shown that a Möbius strip soap film rendered unstable by deforming its frame changes topology to that of a disk through a "neck-pinching" boundary singularity. This behavior is unlike that of the catenoid, which transitions to two disks through a bulk singularity. It is not yet understood whether the type of singularity is generally a consequence of the surface topology, nor how this dependence could arise from an equation of motion for the surface. To address these questions we investigate experimentally, computationally, and theoretically the route to singularities of soap films with different topologies, including a family of punctured Klein bottles. We show that the location of singularities (bulk or boundary) may depend on the path of the boundary deformation. In the unstable regime the driving force for soap-film motion is the mean curvature. Thus, the narrowest part of the neck, associated with the shortest nontrivial closed geodesic of the surface, has the highest curvature and is the fastest moving. Just before onset of the instability there exists on the stable surface the shortest closed geodesic, which is the initial condition for evolution of the neck's geodesics, all of which have the same topological relationship to the frame. We make the plausible conjectures that if the initial geodesic is linked to the boundary, then the singularity will occur at the boundary, whereas if the two are unlinked initially, then the singularity will occur in the bulk. Numerical study of mean curvature flows and experiments support these conjectures.
Tangled nonlinear driven chain reactions of all optical singularities
NASA Astrophysics Data System (ADS)
Vasil'ev, V. I.; Soskin, M. S.
2012-03-01
Dynamics of polarization optical singularities chain reactions in generic elliptically polarized speckle fields created in photorefractive crystal LiNbO3 was investigated in details Induced speckle field develops in the tens of minutes scale due to photorefractive 'optical damage effect' induced by incident beam of He-Ne laser. It was shown that polarization singularities develop through topological chain reactions of developing speckle fields driven by photorefractive nonlinearities induced by incident laser beam. All optical singularities (C points, optical vortices, optical diabolos,) are defined by instantaneous topological structure of the output wavefront and are tangled by singular optics lows. Therefore, they have develop in tangled way by six topological chain reactions driven by nonlinear processes in used nonlinear medium (photorefractive LiNbO3:Fe in our case): C-points and optical diabolos for right (left) polarized components domains with orthogonally left (right) polarized optical vortices underlying them. All elements of chain reactions consist from loop and chain links when nucleated singularities annihilated directly or with alien singularities in 1:9 ratio. The topological reason of statistics was established by low probability of far enough separation of born singularities pair from existing neighbor singularities during loop trajectories. Topology of developing speckle field was measured and analyzed by dynamic stokes polarimetry with few seconds' resolution. The hierarchy of singularities govern scenario of tangled chain reactions was defined. The useful space-time data about peculiarities of optical damage evolution were obtained from existence and parameters of 'islands of stability' in developing speckle fields.
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Singularity Preserving Numerical Methods for Boundary Integral Equations
NASA Technical Reports Server (NTRS)
Kaneko, Hideaki (Principal Investigator)
1996-01-01
In the past twelve months (May 8, 1995 - May 8, 1996), under the cooperative agreement with Division of Multidisciplinary Optimization at NASA Langley, we have accomplished the following five projects: a note on the finite element method with singular basis functions; numerical quadrature for weakly singular integrals; superconvergence of degenerate kernel method; superconvergence of the iterated collocation method for Hammersteion equations; and singularity preserving Galerkin method for Hammerstein equations with logarithmic kernel. This final report consists of five papers describing these projects. Each project is preceeded by a brief abstract.
Ordinary polarization singularities in three-dimensional optical fields.
Freund, Isaac
2012-06-15
In generic three-dimensional optical fields the canonical point polarization singularities are points of circular polarization, C points on C lines, and points of linear polarization, L points on L lines. These special points are surrounded by a sea of ordinary points. In planes oriented normal to the principle axes of the polarization ellipse at the point, every ordinary point is also a singularity, here an ordinary polarization singularity, or O point. Interactions between O points, between O points and C points, and between O points and L points are described that highlight the fact that a consistent description of optical fields containing C and L lines must include O points.
Singularities of the Euler equation and hydrodynamic stability
NASA Technical Reports Server (NTRS)
Tanveer, S.; Speziale, Charles G.
1992-01-01
Equations governing the motion of a specific class of singularities of the Euler equation in the extended complex spatial domain are derived. Under some assumptions, it is shown how this motion is dictated by the smooth part of the complex velocity at a singular point in the unphysical domain. These results are used to relate the motion of complex singularities to the stability of steady solutions of the Euler equation. A sufficient condition for instability is conjectured. Several examples are presented to demonstrate the efficacy of this sufficient condition which include the class of elliptical flows and the Kelvin-Stuart Cat's Eye.
Spontaneous generation of singularities in paraxial optical fields.
Aiello, Andrea
2016-04-01
In nonrelativistic quantum mechanics, the spontaneous generation of singularities in smooth and finite wave functions is a well understood phenomenon also occurring for free particles. We use the familiar analogy between the two-dimensional Schrödinger equation and the optical paraxial wave equation to define a new class of square-integrable paraxial optical fields that develop a spatial singularity in the focal point of a weakly focusing thin lens. These fields are characterized by a single real parameter whose value determines the nature of the singularity. This novel field enhancement mechanism may stimulate fruitful research for diverse technological and scientific applications. PMID:27192314
On the Singular Perturbations for Fractional Differential Equation
Atangana, Abdon
2014-01-01
The goal of this paper is to examine the possible extension of the singular perturbation differential equation to the concept of fractional order derivative. To achieve this, we presented a review of the concept of fractional calculus. We make use of the Laplace transform operator to derive exact solution of singular perturbation fractional linear differential equations. We make use of the methodology of three analytical methods to present exact and approximate solution of the singular perturbation fractional, nonlinear, nonhomogeneous differential equation. These methods are including the regular perturbation method, the new development of the variational iteration method, and the homotopy decomposition method. PMID:24683357
Nondimensional forms for singular perturbation analyses of aircraft energy climbs
NASA Technical Reports Server (NTRS)
Calise, A. J.; Markopoulos, N.; Corban, J. E.
1991-01-01
This paper proposes a systematic approach for identifying the perturbation parameter in singular perturbation analysis of aircraft optimal guidance, and in particular considers a family of problems related to aircraft energy climbs. The approach, which is based on a nondimensionalization of the equations of motion, is used to evaluatae the appropriateness of forced singular perturbation formulations used in the past for transport and fighter aircraft, and to assess the applicability of energy state approximations and singular perturbation analysis for airbreathing transatmospheric vehicles with hypersonic cruise and orbital capabilities.
Naked singularities in higher dimensional Vaidya space-times
Ghosh, S. G.; Dadhich, Naresh
2001-08-15
We investigate the end state of the gravitational collapse of a null fluid in higher-dimensional space-times. Both naked singularities and black holes are shown to be developing as the final outcome of the collapse. The naked singularity spectrum in a collapsing Vaidya region (4D) gets covered with the increase in dimensions and hence higher dimensions favor a black hole in comparison to a naked singularity. The cosmic censorship conjecture will be fully respected for a space of infinite dimension.
On the solution of integral equations with strongly singular kernels
NASA Technical Reports Server (NTRS)
Kaya, A. C.; Erdogan, F.
1987-01-01
Some useful formulas are developed to evaluate integrals having a singularity of the form (t-x) sup-m, m greater than or equal 1. Interpreting the integrals with strong singularities in Hadamard sense, the results are used to obtain approximate solutions of singular integral equations. A mixed boundary value problem from the theory of elasticity is considered as an example. Particularly for integral equations where the kernel contains, in addition to the dominant term (t-x) sup-m, terms which become unbounded at the end points, the present technique appears to be extremely effective to obtain rapidly converging numerical results.
On the solution of integral equations with strongly singular kernels
NASA Technical Reports Server (NTRS)
Kaya, A. C.; Erdogan, F.
1986-01-01
Some useful formulas are developed to evaluate integrals having a singularity of the form (t-x) sup-m ,m greater than or equal 1. Interpreting the integrals with strong singularities in Hadamard sense, the results are used to obtain approximate solutions of singular integral equations. A mixed boundary value problem from the theory of elasticity is considered as an example. Particularly for integral equations where the kernel contains, in addition to the dominant term (t-x) sup -m , terms which become unbounded at the end points, the present technique appears to be extremely effective to obtain rapidly converging numerical results.
Configuration of singular optical cones in gyrotropic crystals with dichroism
Merkulov, V. S.
2015-02-15
Optical conic singularities in crystals with linear dichroism and natural optical activity at the point of intersection of dispersion curves for the main refractive indices are considered. The possible existence of singularities like a nodal point, tangency point, triple point, and cusps of the first and second order is demonstrated. Forty-nine different types of irreducible fourth-order optical cones obtained by sequential bifurcations of eight main singular cones are established. The classification is based on the concept of roughness of systems depending on parameters.
Spatial Distribution of Phase Singularities in Optical Random Vector Waves.
De Angelis, L; Alpeggiani, F; Di Falco, A; Kuipers, L
2016-08-26
Phase singularities are dislocations widely studied in optical fields as well as in other areas of physics. With experiment and theory we show that the vectorial nature of light affects the spatial distribution of phase singularities in random light fields. While in scalar random waves phase singularities exhibit spatial distributions reminiscent of particles in isotropic liquids, in vector fields their distribution for the different vector components becomes anisotropic due to the direct relation between propagation and field direction. By incorporating this relation in the theory for scalar fields by Berry and Dennis [Proc. R. Soc. A 456, 2059 (2000)], we quantitatively describe our experiments. PMID:27610854
Particle Production and Big Rip Singularities
NASA Astrophysics Data System (ADS)
Bates, Jason
2010-02-01
In 1929, Edwin Hubble found that objects in our Universe generally recede from us at a rate proportional to their distance, suggesting that the Universe as a whole is expanding. More recently, astronomers have observed that this expansion is accelerating. According to Einstein's theory of gravity, all normal matter in the Universe should act to slow the rate of expansion, so there must be something new which is causing this acceleration. Cosmologists call this ``Dark Energy.'' One of the possibilities for dark energy leads to a Universe which expands to an infinite size in a finite amount of time. This scenario is called a ``Big Rip,'' because near the end of time this expansion overcomes all other forces in the Universe - even atoms are ripped apart. However, Quantum Mechanics predicts that as the Universe expands particles will be created. If enough particles are created, this process could slow or even halt the expansion, and the ``Big Rip'' might be avoided. Using numerical methods, we considered the quantum effects for massive and massless scalar fields, and found that while at late times quantum effects do grow large, they do not become comparable to the dark energy until very near the singularity when the curvature of the Universe approaches the Planck scale. )
Extreme value theory for singular measures.
Lucarini, Valerio; Faranda, Davide; Turchetti, Giorgio; Vaienti, Sandro
2012-06-01
In this paper, we perform an analytical and numerical study of the extreme values of specific observables of dynamical systems possessing an invariant singular measure. Such observables are expressed as functions of the distance of the orbit of initial conditions with respect to a given point of the attractor. Using the block maxima approach, we show that the extremes are distributed according to the generalised extreme value distribution, where the parameters can be written as functions of the information dimension of the attractor. The numerical analysis is performed on a few low dimensional maps. For the Cantor ternary set and the Sierpinskij triangle, which can be constructed as iterated function systems, the inferred parameters show a very good agreement with the theoretical values. For strange attractors like those corresponding to the Lozi and Hènon maps, a slower convergence to the generalised extreme value distribution is observed. Nevertheless, the results are in good statistical agreement with the theoretical estimates. It is apparent that the analysis of extremes allows for capturing fundamental information of the geometrical structure of the attractor of the underlying dynamical system, the basic reason being that the chosen observables act as magnifying glass in the neighborhood of the point from which the distance is computed.
Accessing singular antecedents in conjoined phrases.
Albrecht, J E; Clifton, C
1998-05-01
Two experiments examined processing of singular pronouns when the antecedent (e.g., Mary) was a noun phrase (NP) in a conjoined phrase (e.g., Mary and John). Whole-sentence reading times showed an increase in processing time associated with splitting the conjoined phrase to access a single NP antecedent. The increase in processing occurred both when the antecedent was in the subject position and when it was in a nonsubject position. The source of the disruption was further investigated using eyetracking methods. Summing over regions of the text, the magnitude of the processing cost incurred by having to split a conjoined NP was closely comparable when there was and when there was not a gender-appropriate distracting potential antecedent. When there was no such potential antecedent, the increase in processing time occurred immediately in the pronoun region when eye movements were measured. In contrast, when there was a second discourse entity that matched the gender and number of the pronoun (but was not a plausible antecedent for the pronoun), eyetracking measures suggested that the processing difficulty was delayed until additional information was read that forced the antecedent to be one of the conjoined NPs. The results are interpreted in terms of Sanford and Garrod's (1981) scenario-based model of text comprehension.
[The Problem of Beginning of the Personal Being In the Anthropology of V. E. Frankl].
Sellés Dauder, Juan Fernando
2016-01-01
In this paper we review the V. E. Frankl' conception of the 'person', which he understands as the superior part in man. This study consists of three parts: a) In the first we study 10 thesis that the father of logotherapy offers on the person, namely: 1st) the person is an individual; 2nd) whitaut possibility of sum; 3rd) is a new being; 4th) is spiritual; 5th) is existential; 6th) is the 'I' or the 'ego'; 7th) provides unity and wholeness; 8th) is dynamic; 9th) is able to transcend and to face herself; 10th) He is not understood by itself but from the point of view of transcendence. b) In the second part are studied 7 synonyms that the founder of the third Viennese school of psychology offers on the person: 1st) individual; 2nd) I; 3rd) personality; 4th) existence; 5th) spirit; 6th) heart; 7th) becoming. c) The third part we review the franklian hypothesis defending that the human person appears after the birth of human biological life. Although it is the third part that gives the the title of this work, it can only be understood, and also reviewed, after having founded in the preceding two parties what specifically understand V.E. Frankl for person. PMID:27637195
Findlay, L; Desai, T; Heath, A; Poole, S; Crivellone, M; Hauck, W; Ambrose, M; Morris, T; Daas, A; Rautmann, G; Buchheit, K H; Spieser, J M; Terao, E
2015-01-01
An international collaborative study was organised jointly by the World Health Organization (WHO)/National Institute for Biological Standards and Control (NIBSC), the United States Pharmacopeia (USP) and the European Directorate for the Quality of Medicines & HealthCare (EDQM/Council of Europe) for the establishment of harmonised replacement endotoxin standards for these 3 organisations. Thirty-five laboratories worldwide, including Official Medicines Control Laboratories (OMCLs) and manufacturers enrolled in the study. Three candidate preparations (10/178, 10/190 and 10/196) were produced with the same material and same formulation as the current reference standards with the objective of generating a new (3(rd)) International Standard (IS) with the same potency (10 000 IU/vial) as the current (2(nd)) IS, as well as new European Pharmacopoeia (Ph. Eur.). and USP standards. The suitability of the candidate preparations to act as the reference standard in assays for endotoxin performed according to compendial methods was evaluated. Their potency was calibrated against the WHO 2(nd) IS for Endotoxin (94/580). Gelation and photometric methods produced similar results for each of the candidate preparations. The overall potency estimates for the 3 batches were comparable. Given the intrinsic assay precision, the observed differences between the batches may be considered unimportant for the intended use of these materials. Overall, these results were in line with those generated for the establishment of the current preparations of reference standards. Accelerated degradation testing of vials stored at elevated temperatures supported the long-term stability of the 3 candidate preparations. It was agreed between the 3 organisations that batch 10/178 be shared between WHO and EDQM and that batches 10/190 and 10/196 be allocated to USP, with a common assigned value of 10 000 IU/vial. This value maintains the continuity of the global harmonisation of reference materials and
Singularity avoidance in the hybrid quantization of the Gowdy model
NASA Astrophysics Data System (ADS)
Tarrío, Paula; Fernández-Méndez, Mikel; Mena Marugán, Guillermo A.
2013-10-01
One of the most remarkable phenomena in loop quantum cosmology is that, at least for homogeneous cosmological models, the big bang is replaced with a big bounce that connects our Universe with a previous branch without passing through a cosmological singularity. The goal of this work is to study the existence of singularities in loop quantum cosmology, including inhomogeneities, and check whether the behavior obtained in the purely homogeneous setting continues to be valid. With this aim, we focus our attention on the three-torus Gowdy cosmologies with linearly polarized gravitational waves and use effective dynamics to carry out the analysis. For this model, we prove that all the potential cosmological singularities are avoided, generalizing the results about resolution of singularities to this scenario with inhomogeneities. We also demonstrate that, if a bounce in the (Bianchi background) volume occurs, the inhomogeneities increase the value of this volume at the bounce with respect to its counterpart in the homogeneous case.
Redundant single gimbal control moment gyroscope singularity analysis
NASA Technical Reports Server (NTRS)
Bedrossian, Nazareth S.; Paradiso, Joseph; Bergmann, Edward V.; Rowell, Derek
1990-01-01
The robotic manipulator is proposed as the mechanical analog to single gimbal control moment gyroscope systems, and it is shown that both systems share similar difficulties with singular configurations. This analogy is used to group gimbal angles corresponding to any momentum state into different families. The singularity problem associated with these systems is examined in detail. In particular, a method is presented to test for the possibility of nontorque-producing gimbal motion at a singular configuration, as well as to determine the admissible motions in the case when this is possible. Sufficient conditions are derived for instances where the singular system can be reconfigured into a nonsingular state by these nontorque-producing motions.
The Cauchy horizon singularity inside Kerr black holes
NASA Astrophysics Data System (ADS)
Burko, Lior M.; Khanna, Gaurav
2016-03-01
The numerical technology that allows for the careful evolution of linearized fields inside Kerr black holes and the study of their behavior approaching the Cauchy horizon singularity includes a number of interesting aspects. The latter include compactified hyperboloidal coordinates and foliation, mixed type hyperbolic-elliptic PDE, and initial data evolution where all equal-coordinate hypersurfaces are spacelike. We review the need for the numerical technology that allows for the solution of the spin-2 Teukolsky equation inside Kerr black holes, and discuss the main features thereof. We present new results about the numerical properties of the Cauchy horizon singularity and their correspondence with the predictions of perturbative analysis. We then discuss present directions of study, which include the sub-dominant azimuthal modes, approaching the Cauchy horizon singularity along timelike directions, approaching the Marolf-Ori (``outflying'') singularity and the studying the fields along the Cauchy horizon.
Object detection with a multistatic array using singular value decomposition
Hallquist, Aaron T.; Chambers, David H.
2014-07-01
A method and system for detecting the presence of subsurface objects within a medium is provided. In some embodiments, the detection system operates in a multistatic mode to collect radar return signals generated by an array of transceiver antenna pairs that is positioned across a surface and that travels down the surface. The detection system converts the return signals from a time domain to a frequency domain, resulting in frequency return signals. The detection system then performs a singular value decomposition for each frequency to identify singular values for each frequency. The detection system then detects the presence of a subsurface object based on a comparison of the identified singular values to expected singular values when no subsurface object is present.
Grand rip and grand bang/crunch cosmological singularities
NASA Astrophysics Data System (ADS)
Fernández-Jambrina, L.
2014-09-01
The present accelerated expansion of the Universe has enriched the list of possible scenarios for its fate, singular or not. In this paper a unifying framework for analyzing such behaviors is proposed, based on generalized power and asymptotic expansions of the barotropic index w, or equivalently of the deceleration parameter q, in terms of the time coordinate. Besides well-known singular and nonsingular future behaviors, other types of strong singularities appear around the phantom divide in flat models, with features similar to those of big rip or big bang/crunch, which we have dubbed "grand rip" and "grand bang/crunch," respectively, since energy density and pressure diverge faster than t-2 in coordinate time. In addition to this, the scale factor does not admit convergent generalized power series around these singularities with a finite number of terms with negative powers.
Why do naked singularities form in gravitational collapse? II
Joshi, Pankaj S.; Goswami, Rituparno; Dadhich, Naresh
2004-10-15
We examine physical features that could lead to formation of a naked singularity rather than black hole, as end state of spherical collapse. Generalizing earlier results on dust collapse to general type I matter fields, it is shown that collapse always creates black hole if shear vanishes or density is homogeneous. It follows that nonzero shear is a necessary condition for singularity to be visible to external observers, when trapped surface formation is delayed by shearing forces or inhomogeneity within the collapsing cloud.
Higher order matrix differential equations with singular coefficient matrices
Fragkoulis, V. C.; Kougioumtzoglou, I. A.; Pantelous, A. A.; Pirrotta, A.
2015-03-10
In this article, the class of higher order linear matrix differential equations with constant coefficient matrices and stochastic process terms is studied. The coefficient of the highest order is considered to be singular; thus, rendering the response determination of such systems in a straightforward manner a difficult task. In this regard, the notion of the generalized inverse of a singular matrix is used for determining response statistics. Further, an application relevant to engineering dynamics problems is included.
Classical resolution of black hole singularities via wormholes
NASA Astrophysics Data System (ADS)
Olmo, Gonzalo J.; Rubiera-Garcia, D.; Sanchez-Puente, A.
2016-03-01
In certain extensions of General Relativity, wormholes generated by spherically symmetric electric fields can resolve black hole singularities without necessarily removing curvature divergences. This is shown by studying geodesic completeness, the behavior of time-like congruences going through the divergent region, and by means of scattering of waves off the wormhole. This provides an example of the logical independence between curvature divergences and space-time singularities, concepts very often identified with each other in the literature.
Switched impulsive control of the endocrine disruptor diethylstilbestrol singular model
NASA Astrophysics Data System (ADS)
Zamani, Iman; Shafiee, Masoud; Ibeas, Asier; de la Sen, M.
2014-12-01
In this work, a switched and impulsive controller is designed to control the Endocrine Disruptor Diethylstilbestrol mechanism which is usually modeled as a singular system. Then the exponential stabilization property of the proposed switched and impulsive singular model is discussed under matrix inequalities. A design algorithm is given and applied for the physiological process of endocrine disruptor diethylstilbestrol model to illustrate the effectiveness of the results.
Ghost free massive gravity with singular reference metrics
NASA Astrophysics Data System (ADS)
Zhang, Hongsheng; Li, Xin-Zhou
2016-06-01
An auxiliary metric (reference metric) is inevitable in massive gravity theory. In the scenario of the gauge/gravity duality, massive gravity with a singular reference metric is used to study momentum dissipation, which describes the electric and heat conductivity for normal conductors. We demonstrate in detail that the de Rham-Gabadadze-Tolley (dRGT) massive gravity with a singular reference metric is ghost free.
Radiation Therapy Physics, 3rd Edition
NASA Astrophysics Data System (ADS)
Hendee, William R.; Ibbott, Geoffrey S.; Hendee, Eric G.
2004-08-01
The Third Edition of Radiation Therapy Physics addresses in concise fashion the fundamental diagnostic radiologic physics principles as well as their clinical implications. Along with coverage of the concepts and applications for the radiation treatment of cancer patients, the authors have included reviews of the most up-to-date instrumentation and critical historical links. The text includes coverage of imaging in therapy planning and surveillance, calibration protocols, and precision radiation therapy, as well as discussion of relevant regulation and compliance activities. It contains an updated and expanded section on computer applications in radiation therapy and electron beam therapy, and features enhanced user-friendliness and visual appeal with a new, easy-to-follow format, including sidebars and a larger trim size. With its user-friendly presentation and broad, comprehensive coverage of radiotherapy physics, this Third Edition doubles as a medical text and handy professional reference.
Coal mine ground control. 3rd ed.
Peng, S.S.
2008-09-15
The third edition not only completely revises and updates the original subject areas, but also is broadened to include a number of new topics such as high horizontal stresses, computer modeling, and highwall stability. The subject areas covered in this book define the current field of coal mine ground control, except for the recently emerging topic of mine seals and some conventional subjects such as coal/rock cutting and impoundment dams. It contains 1,134 references from all published sources, and archived since 1876.
Cerebral computed tomography, 3rd Edition
Weisberg, L.; Nice, C.
1988-01-01
This book is an introduction to the utilization of computed tomography in evaluating patients with intracranial and orbital disorders. It features clinical correlations and provides an overview of general principles, performance, and normal anatomy of CT. It covers evaluation of specific neurologic signs and symptoms, including stroke, metastatic disease, increased intracranial pressure, head injury, pediatric conditions, and more.
Presenting the 3rd edition of WRB
NASA Astrophysics Data System (ADS)
Schad, Peter
2014-05-01
The third edition of the international soil classification system "World Reference Base for Soil Resources" (WRB) will be presented during der 20th World Congress of Soil Science, Jeju, Korea, June 9-12. The second edition was published in 2006 and the first in 1998, which, in turn, was based on the Legends of the FAO Soil Map of the World. Now, after eight years of experience with the second edition, time was due for a revision. The major changes are: 1. The second edition had two different qualifier sequences for naming soils (IUSS Working Group WRB, 2006, update 2007) and for creating map legends (Guidelines for creating small-scale map legends using the WRB; IUSS Working Group WRB, 2010). The third edition has one sequence for both. The qualifiers for every Reference Soil Group are subdivided into a small number of main qualifiers that are ranked and a larger number of additional qualifiers that are not ranked and given in an alphabetical order. The name of a pedon must comprise all applying qualifiers. The name of a map unit comprises a specified small number of main qualifiers, depending on scale, whereas all other qualifiers are optional. 2. For some soils, problems have been reported. Albeluvisols are difficult to detect in the field and cover only small surfaces. They have been replaced by Retisols, which have a broader definition that is easier to identify in the field. 3. The use of some diagnostics was difficult. Examples are: The argic horizon had too low limit values, so we had much more soils with argic horizons than justified. The definitions of the cambic horizon and the gleyic and stagnic properties were not precise enough. Organic material, mollic and umbric horizons had an unnecessary complicated definition. 4. Some changes in the key to the Reference Soil Groups seemed to be justified. Fluvisols were moved further down, Durisols and Gypsisols switched their position, also Arenosols and Cambisols. The soils with an argic horizon were brought into a new sequence. 5. The umbrella function of WRB aims to allow the allocation of soil classes existing in a national classification system within the WRB. Characteristics that in a national system are regarded to be important must be considered in WRB - not necessarily at the highest level, but at least somewhere. The third edition of WRB allows a better accommodation of soil types, e.g., of the Australian and the Brazilian system. 6. Some environments or even ecoregions had not been well represented in WRB. The third edition allows a better accommodation of soils of ultra-continental permafrost regions, acid-sulphate soils and Technosols. 7. How to explain complicated sets of characteristics? For the third edition, efforts were made to give better structured definitions that can be more easily grasped. The editors of the third edition are convinced that the new WRB allows a more precise classification of soils including both, a better naming of pedons and a better elaboration of soil map legends.
Peace Corps. 3rd Annual Report.
ERIC Educational Resources Information Center
Peace Corps, Washington, DC.
Projects, operations, and future plans are covered in this annual report for the third year of the Peace Corps. An introduction comments on returning volunteers and presents regional maps with tables for Latin America, Africa, Near East and South Asia, and Far East. Section 1 contains letters and reports from volunteers in Peru, Ivory Coast,…
Teaching Visually Impaired Children. 3rd Edition
ERIC Educational Resources Information Center
Bishop, Virginia E.
2004-01-01
In this exceptional new third edition, the author has retained much of the practical "how to" approach of the previous editions, but adds depth in two dimensions: learning theory and the educational process. This book is "so comprehensive in scope and complete in detail that it would be the most likely recommended" (from the foreword by Dr.…
Fundamentals of nuclear pharmacy, 3rd Ed
Saha, G.B. )
1992-01-01
This book is a standard text/reference of nuclear pharmacy. New sections in the Third Edition include: instruments used for radiation detection and measurement; disposal of radioactive materials; clinical uses of all new and existing radiopharmaceuticals; 99m Tc and 123I-labeled radiopharmaceuticals, as well as radiolabeled leukocytes, platelets, and antibodies; and up-to-date descriptions of the latest FDA regulations.
The 3rd International Microgravity Combustion Workshop
NASA Technical Reports Server (NTRS)
Ross, Howard D. (Compiler)
1995-01-01
This Conference Publication contains 71 papers presented at the Third International Microgravity Combustion Workshop held in Cleveland, Ohio, from April 11 to 13, 1995. The purpose of the workshop was twofold: to exchange information about the progress and promise of combustion science in microgravity and to provide a forum to discuss which areas in microgravity combustion science need to be expanded profitably and which should be included in upcoming NASA Research Announcements (NRA).
The Physics of Glaciers, 3rd Edition
NASA Astrophysics Data System (ADS)
Bahr, David
At one time or another, who among us has not marveled at the beauty of the snow and ice-covered Alps, or admired the tenacity of polar explorers and the adventurous spirits of climbers on the glacier-clad summits of the high Himalaya? The fascination of distant ice covered expanses has enlisted more than a few recruits into the ranks of glaciologists, but many, if not most, of today's students of glaciology are a slightly less romantic and more mathematical lot, attracted by the quantitative world of physics and the applied sciences of polar climatology, ice mechanics, and snow hydrology.Once a relatively quiet branch of geophysics filled with venturesome climbers capable of reaching the objects of their study, glaciology is now a field that is fueled by a rapid influx of talent, technology, and new ideas due to the increasingly acknowledged relationships between global climate, sea level, and ice sheets. While the understanding of glacier processes has seen significant progress, as a result there is also a sense of being overwhelmed by the voluminous and sometimes speculative theories and field observations associated with an expanding discipline.
A Beginning. Revised 3rd Edition.
ERIC Educational Resources Information Center
Healy, Mary K.; Root, Phyllis
This document contains a selection of materials focusing on man acting to know, preserve, and improve his environment. The booklet is divided into three parts. Part one presents a listing of objectives. They reflect a need for all to become aware of the problems that plague our environment. Furthermore, they indicate that the ecological…
3rd Brazilian Consensus on Helicobacter pylori.
Coelho, Luiz Gonzaga; Maguinilk, Ismael; Zaterka, Schlioma; Parente, José Miguel; do Carmo Friche Passos, Maria; Moraes-Filho, Joaquim Prado P
2013-04-01
Signicant progress has been obtained since the Second Brazilian Consensus Conference on Helicobacter pylori Infection held in 2004, in São Paulo, SP, Brazil, and justify a third meeting to establish updated guidelines on the current management of H. pylori infection. The Third Brazilian Consensus Conference on H pylori Infection was organized by the Brazilian Nucleus for the Study of Helicobacter, a Department of the Brazilian Federation of Gastroenterology and took place on April 12-15, 2011, in Bento Gonçalves, RS, Brazil. Thirty-one delegates coming from the five Brazilian regions and one international guest, including gastroenterologists, pathologists, epidemiologists, and pediatricians undertook the meeting. The participants were allocated in one of the five main topics of the meeting: H pylori, functional dyspepsia and diagnosis; H pylori and gastric cancer; H pylori and other associated disorders; H pylori treatment and retreatment; and, epidemiology of H pylori infection in Brazil. The results of each subgroup were submitted to a final consensus voting to all participants. Relevant data were presented, and the quality of evidence, strength of recommendation, and level of consensus were graded. Seventy per cent and more votes were considered as acceptance for the final statement. This article presents the main recommendations and conclusions to guide Brazilian doctors involved in the management of H pylori infection.
Elementary Science Guide -- 3rd Grade.
ERIC Educational Resources Information Center
Wieland, Anne; And Others
Presented is a resource book to be used with instructional kits for elementary school science students, grade 3. The individual units at this grade level are based on curriculum which has been developed by the National Science Foundation in the 1960s and revised to meet student and teacher identified needs in Anchorage, Alaska. Six units are…
Symmetry breaking and singularity structure in Bose-Einstein condensates
NASA Astrophysics Data System (ADS)
Commeford, K. A.; Garcia-March, M. A.; Ferrando, A.; Carr, Lincoln D.
2012-08-01
We determine the trajectories of vortex singularities that arise after a single vortex is broken by a discretely symmetric impulse in the context of Bose-Einstein condensates in a harmonic trap. The dynamics of these singularities are analyzed to determine the form of the imprinted motion. We find that the symmetry-breaking process introduces two effective forces: a repulsive harmonic force that causes the daughter trajectories to be ejected from the parent singularity and a Magnus force that introduces a torque about the axis of symmetry. For the analytical noninteracting case we find that the parent singularity is reconstructed from the daughter singularities after one period of the trapping frequency. The interactions between singularities in the weakly interacting system do not allow the parent vortex to be reconstructed. Analytic trajectories were compared to the actual minima of the wave function, showing less than 0.5% error for an impulse strength of v=0.00005. We show that these solutions are valid within the impulse regime for various impulse strengths using numerical integration of the Gross-Pitaevskii equation. We also show that the actual duration of the symmetry-breaking potential does not significantly change the dynamics of the system as long as the strength is below v=0.0005.
Feedback control of singular systems with applications to incompressible flows
NASA Astrophysics Data System (ADS)
Gandikota, Ramakrishna V.
2000-10-01
Singular systems of differential equations, also referred to as differential algebraic equation (DAE) systems, arise as models in a variety of engineering applications. In chemical engineering, they typically arise under the quasi-steady state assumptions of phase, reaction or thermal equilibrium in the modeling of processes with fast mass transfer, reaction or heat transfer. They also arise in incompressible fluid flow systems. The control of singular systems has attracted considerable attention in the last two decades. The majority of the developed methods are on the state feedback control of linear and nonlinear singular systems in continuous-time, and they rely on the derivation of standard state space realizations (i.e. ODE descriptions) that can be used as the basis for the controller design. This thesis addresses (i) the derivation of state space realizations for the output feedback control of linear singular systems in continuous time, (ii) the derivation of state space realizations of singular systems of difference equations, which can be used for the state feedback control of nonlinear discrete time singular systems, (iii) a parallel analysis of the continuous in space and discretized in space incompressible Navier Stokes equations, with emphasis on the derivation of standard PDE and ODE descriptions respectively, and (iv) a case study on the numerical simulation and feedback control of the flow pattern in a lid-driven cavity. The performance of the developed controllers is illustrated via numerical simulation studies.
Local analysis near a folded saddle-node singularity
NASA Astrophysics Data System (ADS)
Krupa, Martin; Wechselberger, Martin
Folded saddle-nodes occur generically in one parameter families of singularly perturbed systems with two slow variables. We show that these folded singularities are the organizing centers for two main delay phenomena in singular perturbation problems: canards and delayed Hopf bifurcations. We combine techniques from geometric singular perturbation theory—the blow-up technique—and from delayed Hopf bifurcation theory—complex time path analysis—to analyze the flow near such folded saddle-nodes. In particular, we show the existence of canards as intersections of stable and unstable slow manifolds. To derive these canard results, we extend the singularly perturbed vector field into the complex domain and study it along elliptic paths. This enables us to extend the invariant slow manifolds beyond points where normal hyperbolicity is lost. Furthermore, we define a way-in/way-out function describing the maximal delay expected for generic solutions passing through a folded saddle-node singularity. Branch points associated with the change from a complex to a real eigenvalue structure in the variational equation along the critical (slow) manifold make our analysis significantly different from the classical delayed Hopf bifurcation analysis where these eigenvalues are complex only.
Singular Spectrum Analysis With Missing Data
NASA Astrophysics Data System (ADS)
Kondrashov, D.; Feliks, Y.; Ghil, M.
2004-12-01
A Singular Spectrum Analysis (SSA) with gaps of missing data is presented. SSA is a data-adaptive, non-parametric spectral method based on diagonalizing the lag-covariance matrix of a time series. Using leading oscillatory SSA modes, we iteratively produce estimates of missing data, which are then used to compute a self-consistent lag-covariance matrix. For a univariate record, SSA imputation utilizes only temporal correlations in the data to fill up missing points. For a multivariate record, multi-channel SSA imputation takes advantage of both spatial and temporal correlations. Analyzing the whole available record with the missing points filled, allows for greater accuracy and better significance testing in the spectral analysis. It also provides information on the evolution of the oscillatory modes in the gaps. We use cross-validation to optimize the SSA window width and number of SSA modes to fill the gaps. The algorithm is applied to the extended (A.D. 622--1922) historical records of the low- and high-water levels of the Nile River at Cairo. We fill in the large gaps in the later part of the records (A.D. 1471--1922), and identify statistically significant interannual and interdecadal periodicities. Our analysis suggests that the 7-year periodicity in the records, possibly related to the biblical "Joseph" cycle, is due to North-Atlantic influences. We find that the climate shifts at the beginning and the end of the Medieval Warm Period were fairly abrupt and affected several climatic modes of variability.
NASA Astrophysics Data System (ADS)
Benowitz, J.
2007-12-01
The 2002 November 3rd, 7.9 M Denali Fault caused a large landslide that deposited 11.4 x 106m3 feet of rock and ice onto the SE fork of McGinnis Peak Glacier. The landslide left a large mass on the upper ice reservoir of the glacier and blocked the terminus outlet of the glacier with debris. Satellite images and historic photos were used to examine the terminus history of the glacier. Further landslides/mass wasting events during the spring of 2003, documented via Land Sat 7 images, covered the same upper ice reservoir as the 2002 landslides. Between 2004 and 2006 the SE fork Glacier of McGinnis Peak experienced a dramatic surge. There is no known history of such dramatic surge occurrences on the glacier of interest. Though causation is difficult to prove preliminary evidence points towards the implication that the landslides generated by the 2002 earthquake most likely either caused or contributed to the documented glacial surge. Examination of more satellite images is planned to further examine McGinnis Peak's glacier history and to refine the timing of the possible correlation between the earthquake generated landslides and the dramatic surge of the SE glacial fork of McGinnis Peak
Gelband, Hellen; Sankaranarayanan, Rengaswamy; Gauvreau, Cindy L; Horton, Susan; Anderson, Benjamin O; Bray, Freddie; Cleary, James; Dare, Anna J; Denny, Lynette; Gospodarowicz, Mary K; Gupta, Sumit; Howard, Scott C; Jaffray, David A; Knaul, Felicia; Levin, Carol; Rabeneck, Linda; Rajaraman, Preetha; Sullivan, Terrence; Trimble, Edward L; Jha, Prabhat
2016-05-21
Investments in cancer control--prevention, detection, diagnosis, surgery, other treatment, and palliative care--are increasingly needed in low-income and particularly in middle-income countries, where most of the world's cancer deaths occur without treatment or palliation. To help countries expand locally appropriate services, Cancer (the third volume of nine in Disease Control Priorities, 3rd edition) developed an essential package of potentially cost-effective measures for countries to consider and adapt. Interventions included in the package are: prevention of tobacco-related cancer and virus-related liver and cervical cancers; diagnosis and treatment of early breast cancer, cervical cancer, and selected childhood cancers; and widespread availability of palliative care, including opioids. These interventions would cost an additional US$20 billion per year worldwide, constituting 3% of total public spending on health in low-income and middle-income countries. With implementation of an appropriately tailored package, most countries could substantially reduce suffering and premature death from cancer before 2030, with even greater improvements in later decades.
Niang, C I; Shisana, O; Andrews, G; Kaseje, D; Simbayi, L; Peltzer, K; Toefy, Y
2006-08-01
Africa's HIV/AIDS situation remains cause for concern. The impact of HIV is considerable and threatens the survival and development of African societies. Although much has been attempted, the results still leave much to be desired. AIDS is an epidemic that needs to be addressed with much creativity and spirit of initiative. It is against this background that the 3rd African conference on the social aspects of HIV/AIDS brought innovations in the way international conferences are designed, activities implemented and results obtained. The innovations concerned the approach to international conferences and take into account reconceptualising HIV/AIDS so as to encourage holistic approaches and better visibility of vulnerable groups. The activities of the conference were organised in such a way as to get people living with HIV/AIDS (PLWHA), grassroots communities and marginalised groups to play a focal role. The conference offered an opportunity for developing cultural activities that would translate the African cultural concepts that had been identified as important in the HIV situation and response analysis. Interaction at the conference created an opportunity to analyse the various dimensions of the political, cultural and economic determinants. The conference offered food for thought around response construction while singling out the themes of urgency and acceleration of response, synergy construction, and coordination and conception of political responses.
2012-01-01
From November 4th- 6th 2011, the 3rd NEUROWIND e.V. meeting was held in Motzen, Brandenburg, Germany. Like in the previous years, the meeting provided an excellent platform for scientific exchange and the presentation of innovative projects for young colleagues in the fields of neurovascular research, neuroinflammation and neurodegeneration. As kick-off to the scientific sessions, Reinhard Hohlfeld, Head of the Institute for Clinical Neuroimmunology in Munich, gave an illustrious overview on the many fascinations of neuroimmunologic research. A particular highlight on the second day of the meeting was the award of the 1'st NEUROWIND e.V. prize for young academics in the field of experimental neurology. This award is posted for young colleagues under the age of 35 with a significant achievement in the field of neurovascular research, neuroinflammation or neurodegeneration and comprises an amount of 20.000 Euro, founded by Merck Serono GmbH, Darmstadt. Germany. The first prize was awarded to Ivana Nikic from Martin Kerschensteiner's group in Munich for her brilliant work on a reversible form of axon damage in experimental autoimmune encephalomyelitis and multiple sclerosis, published in Nature Medicine in 2011. This first prize award ceremony was a great incentive for the next call for proposals now upcoming in 2012. PMID:22360825
Nkwescheu, Armand Seraphin; Fokam, Joseph; Tchendjou, Patrice; Nji, Akindeh; Ngouakam, Hermann; Andre, Bita Fouda; Joelle, Sobngwi; Uzochukwu, Benjamin; Akinroye, Kingsley; Mbacham, Wilfred; Colizzi, Vittorio; Leke, Rose; Victora, Cesar
2015-01-01
As the study of disease occurrence and health indicators in human populations, Epidemiology is a dynamic field that evolves with time and geographical context. In order to update African health workers on current epidemiological practices and to draw awareness of early career epidemiologists on concepts and opportunities in the field, the 3rd African Epidemiology Association and the 1st Cameroon Society of Epidemiology Conference was organized in June 2-6, 2014 at the Yaoundé Mont Febe Hotel, in Cameroon. Under the theme«Practice of Epidemiology in Africa: Stakes, Challenges and Perspectives», the conference attracted close to five hundred guest and participants from all continents. The two main programs were the pre-conference course for capacity building of African Early Career epidemiologists, and the conference itself, providing a forum for scientific exchanges on recent epidemiological concepts, encouraging the use of epidemiological methods in studying large disease burden and neglected tropical diseases; and highlighting existing opportunities. PMID:26523191
Gelband, Hellen; Sankaranarayanan, Rengaswamy; Gauvreau, Cindy L; Horton, Susan; Anderson, Benjamin O; Bray, Freddie; Cleary, James; Dare, Anna J; Denny, Lynette; Gospodarowicz, Mary K; Gupta, Sumit; Howard, Scott C; Jaffray, David A; Knaul, Felicia; Levin, Carol; Rabeneck, Linda; Rajaraman, Preetha; Sullivan, Terrence; Trimble, Edward L; Jha, Prabhat
2016-05-21
Investments in cancer control--prevention, detection, diagnosis, surgery, other treatment, and palliative care--are increasingly needed in low-income and particularly in middle-income countries, where most of the world's cancer deaths occur without treatment or palliation. To help countries expand locally appropriate services, Cancer (the third volume of nine in Disease Control Priorities, 3rd edition) developed an essential package of potentially cost-effective measures for countries to consider and adapt. Interventions included in the package are: prevention of tobacco-related cancer and virus-related liver and cervical cancers; diagnosis and treatment of early breast cancer, cervical cancer, and selected childhood cancers; and widespread availability of palliative care, including opioids. These interventions would cost an additional US$20 billion per year worldwide, constituting 3% of total public spending on health in low-income and middle-income countries. With implementation of an appropriately tailored package, most countries could substantially reduce suffering and premature death from cancer before 2030, with even greater improvements in later decades. PMID:26578033
Segmentation of singularity maps in the context of soil porosity
NASA Astrophysics Data System (ADS)
Martin-Sotoca, Juan J.; Saa-Requejo, Antonio; Grau, Juan; Tarquis, Ana M.
2016-04-01
Geochemical exploration have found with increasingly interests and benefits of using fractal (power-law) models to characterize geochemical distribution, including concentration-area (C-A) model (Cheng et al., 1994; Cheng, 2012) and concentration-volume (C-V) model (Afzal et al., 2011) just to name a few examples. These methods are based on the singularity maps of a measure that at each point define areas with self-similar properties that are shown in power-law relationships in Concentration-Area plots (C-A method). The C-A method together with the singularity map ("Singularity-CA" method) define thresholds that can be applied to segment the map. Recently, the "Singularity-CA" method has been applied to binarize 2D grayscale Computed Tomography (CT) soil images (Martin-Sotoca et al, 2015). Unlike image segmentation based on global thresholding methods, the "Singularity-CA" method allows to quantify the local scaling property of the grayscale value map in the space domain and determinate the intensity of local singularities. It can be used as a high-pass-filter technique to enhance high frequency patterns usually regarded as anomalies when applied to maps. In this work we will put special attention on how to select the singularity thresholds in the C-A plot to segment the image. We will compare two methods: 1) cross point of linear regressions and 2) Wavelets Transform Modulus Maxima (WTMM) singularity function detection. REFERENCES Cheng, Q., Agterberg, F. P. and Ballantyne, S. B. (1994). The separation of geochemical anomalies from background by fractal methods. Journal of Geochemical Exploration, 51, 109-130. Cheng, Q. (2012). Singularity theory and methods for mapping geochemical anomalies caused by buried sources and for predicting undiscovered mineral deposits in covered areas. Journal of Geochemical Exploration, 122, 55-70. Afzal, P., Fadakar Alghalandis, Y., Khakzad, A., Moarefvand, P. and Rashidnejad Omran, N. (2011) Delineation of mineralization zones in
Chu, C.K.
1993-09-01
Real singularities govern self-focusing singularities and current sheet formation. Complex singularities govern integrable properties, nonintegrable properties, intermittency, and from propagation. This project has studied singularities as both fundamental mathematical objects and as the determining mechanism of crucial physical processes. During the past year, progress was made on: Painleve property and geometry of solvable groups, singularity clustering and psi-lambda series, and current sheet formation in MHD.
Boundary singularities produced by the motion of soap films.
Goldstein, Raymond E; McTavish, James; Moffatt, H Keith; Pesci, Adriana I
2014-06-10
Recent work has shown that a Möbius strip soap film rendered unstable by deforming its frame changes topology to that of a disk through a "neck-pinching" boundary singularity. This behavior is unlike that of the catenoid, which transitions to two disks through a bulk singularity. It is not yet understood whether the type of singularity is generally a consequence of the surface topology, nor how this dependence could arise from an equation of motion for the surface. To address these questions we investigate experimentally, computationally, and theoretically the route to singularities of soap films with different topologies, including a family of punctured Klein bottles. We show that the location of singularities (bulk or boundary) may depend on the path of the boundary deformation. In the unstable regime the driving force for soap-film motion is the mean curvature. Thus, the narrowest part of the neck, associated with the shortest nontrivial closed geodesic of the surface, has the highest curvature and is the fastest moving. Just before onset of the instability there exists on the stable surface the shortest closed geodesic, which is the initial condition for evolution of the neck's geodesics, all of which have the same topological relationship to the frame. We make the plausible conjectures that if the initial geodesic is linked to the boundary, then the singularity will occur at the boundary, whereas if the two are unlinked initially, then the singularity will occur in the bulk. Numerical study of mean curvature flows and experiments support these conjectures. PMID:24843162
Narcissism and the use of personal pronouns revisited.
Carey, Angela L; Brucks, Melanie S; Küfner, Albrecht C P; Holtzman, Nicholas S; Große Deters, Fenne; Back, Mitja D; Donnellan, M Brent; Pennebaker, James W; Mehl, Matthias R
2015-09-01
[Correction Notice: An Erratum for this article was reported in Vol 109(3) of Journal of Personality and Social Psychology (see record 2015-37773-002). The authors erroneously reported the overall correlation, first stated in the abstract, between Narcissism and total first-person-singular use as .02 (.017) instead of .01 (.010). The misreporting of the overall correlation between Narcissism and total use of first-person singular does not change the results or interpretation in any way (i.e., the near-zero association between Narcissism and I-talk). The online version of this article has been corrected.] Among both laypersons and researchers, extensive use of first-person singular pronouns (i.e., I-talk) is considered a face-valid linguistic marker of narcissism. However, the assumed relation between narcissism and I-talk has yet to be subjected to a strong empirical test. Accordingly, we conducted a large-scale (N = 4,811), multisite (5 labs), multimeasure (5 narcissism measures) and dual-language (English and German) investigation to quantify how strongly narcissism is related to using more first-person singular pronouns across different theoretically relevant communication contexts (identity-related, personal, impersonal, private, public, and stream-of-consciousness tasks). Overall (r = .02, 95% CI [-.02, .04]) and within the sampled contexts, narcissism was unrelated to use of first-person singular pronouns (total, subjective, objective, and possessive). This consistent near-zero effect has important implications for making inferences about narcissism from pronoun use and prompts questions about why I-talk tends to be strongly perceived as an indicator of narcissism in the absence of an underlying actual association between the 2 variables. (PsycINFO Database Record
Some aspects of singular interactions in condensed Fermi systems
NASA Astrophysics Data System (ADS)
Stamp, P. C. E.
1993-02-01
This article gives a fairly detailed survey of some of the problems raised when the interaction energy f^{σ σ'}_{k k'} between 2 fermionic quasiparticles (in 2 dimensions) is singular when |k-k'|to 0. Before dealing with singular interactions, it is shown how a non-singular f^{σ σ'}_{k k'} leads to a 2-dimensional Fermi liquid theory, which is internally consistent, at least as far as its infrared properties are concerned. The quasiparticle properties are calculated in detail. The question of whether singular interactions arise for the dilute Fermi gas, with short-range repulsive interactions, is investigated perturbatively. One finds a weak singularity in f^{σ σ'}_{k k'}, when the dimensionality D = 2, but it does not destabilize the Fermi liquid. A more sophisticated analysis is then given, to all orders in the interaction, using the Lippman-Schwinger equation as well as a phase shift analysis for a finite box. The conclusion is that any breakdown of Fermi liquid theory must come from non-perturbative effects. An examination is then made of some of the consequences arising if a singular interaction is introduced — the form proposed by Anderson is used as an example. A hierarchy of singular terms arise in all quantities — this is shown for the self-energy, and also the 3 point and 4 point scattering functions. These may be summed in a perfectly consistent manner. Most attention is given to the particle-hole channel, since it appears to lead to results different from those of Anderson. Nevertheless it appears that it is possible to derive a sensible theory starting from a singular effective Hamiltonian — although Fermi Liquid theory breaks down, all fermionic quantities may be calculated consistently. Finally, the effect of a magnetic field (which cuts off the infrared divergences) is investigated, and the de Haas-van Alphen amplitude calculated, for such a singular Fermionic system.
Loop quantum cosmology and the fate of cosmological singularities
NASA Astrophysics Data System (ADS)
Singh, Parampreet
2014-09-01
Singularities in general relativity such as the big bang and big crunch, and exotic singularities such as the big rip are the boundaries of the classical spacetimes. These events are marked by a divergence in the curvature invariants and the breakdown of the geodesic evolution. Recent progress on implementing techniques of loop quantum gravity to cosmological models reveals that such singularities may be generically resolved because of the quantum gravitational effects. Due to the quantum geometry, which replaces the classical differential geometry at the Planck scale, the big bang is replaced by a big bounce without any assumptions on the matter content or any fine tuning. In this manuscript, we discuss some of the main features of this approach and the results on the generic resolution of singularities for the isotropic as well as anisotropic models. Using effective spacetime description of the quantum theory, we show the way quantum gravitational effects lead to the universal bounds on the energy density, the Hubble rate and the anisotropic shear. We discuss the geodesic completeness in the effective spacetime and the resolution of all of the strong singularities. It turns out that despite the bounds on energy density and the Hubble rate, there can be divergences in the curvature invariants. However such events are geodesically extendible, with tidal forces not strong enough to cause inevitable destruction of the in-falling objects.
The Maslov index and nondegenerate singularities of integrable systems
NASA Astrophysics Data System (ADS)
Foxman, J. A.; Robbins, J. M.
2005-11-01
We consider integrable Hamiltonian systems in {\\mathbb R}^{2n} with integrals of motion F = (F1, ..., Fn) in involution. Nondegenerate singularities of corank one are critical points of F where rank dF = n - 1 and which have definite linear stability. The set of corank-one nondegenerate singularities is a codimension-two symplectic submanifold invariant under the flow. We show that the Maslov index of a closed curve is a sum of contributions ± 2 from the nondegenerate singularities it encloses, the sign depending on the local orientation and stability at the singularities. For one-freedom systems this corresponds to the well-known formula for the Poincaré index of a closed curve as the oriented difference between the number of elliptic and hyperbolic fixed points enclosed. We also obtain a formula for the Liapunov exponent of invariant (n - 1)-dimensional tori in the nondegenerate singular set. Examples include rotationally symmetric n-freedom Hamiltonians, while an application to the periodic Toda chain is described in a companion paper (Foxman and Robbins 2005 Nonlinearity 18 2795-813).
Codimension-3 singularities and Yukawa couplings in F-theory
NASA Astrophysics Data System (ADS)
Hayashi, Hirotaka; Kawano, Teruhiko; Tatar, Radu; Watari, Taizan
2009-12-01
F-theory is one of the frameworks where all the Yukawa couplings of grand unified theories are generated and their computation is possible. The Yukawa couplings of charged matter multiplets are supposed to be generated around codimension-3 singularity points of a base complex 3-fold, and that has been confirmed for the simplest type of codimension-3 singularities in recent studies. However, the geometry of F-theory compactifications is much more complicated. For a generic F-theory compactification, such issues as flux configuration around the codimension-3 singularities, field-theory formulation of the local geometry and behavior of zero-mode wavefunctions have virtually never been addressed before. We address all these issues in this article, and further discuss nature of Yukawa couplings generated at such singularities. In order to calculate the Yukawa couplings of low-energy effective theory, however, the local descriptions of wavefunctions on complex surfaces and a global characterization of zero-modes over a complex curve have to be combined together. We found the relation between them by re-examining how chiral charged matters are characterized in F-theory compactification. An intrinsic definition of spectral surfaces in F-theory turns out to be the key concept. As a biproduct, we found a new way to understand the Heterotic-F theory duality, which improves the precision of existing duality map associated with codimension-3 singularities.
Singular Casimir Elements of the Euler Equation and Equilibrium Points
NASA Astrophysics Data System (ADS)
Yoshida, Zensho; Morrison, Philip J.; Dobarro, Fernando
2013-04-01
The problem of the nonequivalence of the sets of equilibrium points and energy-Casimir extremal points, which occurs in the noncanonical Hamiltonian formulation of equations describing ideal fluid and plasma dynamics, is addressed in the context of the Euler equation for an incompressible inviscid fluid. The problem is traced to a Casimir deficit, where Casimir elements constitute the center of the Poisson algebra underlying the Hamiltonian formulation, and this leads to a study of singularities of the Poisson operator defining the Poisson bracket. The kernel of the Poisson operator, for this typical example of an infinite-dimensional Hamiltonian system for media in terms of Eulerian variables, is analyzed. For two-dimensional flows, a rigorously solvable system is formulated. The nonlinearity of the Euler equation makes the Poisson operator inhomogeneous on phase space (the function space of the state variable), and it is seen that this creates a singularity where the nullity of the Poisson operator (the "dimension" of the center) changes. The problem is an infinite-dimension generalization of the theory of singular differential equations. Singular Casimir elements stemming from this singularity are unearthed using a generalization of the functional derivative that occurs in the Poisson bracket.
Singular Casimir Elements of the Euler Equation and Equilibrium Points
NASA Astrophysics Data System (ADS)
Yoshida, Zensho; Morrison, Philip J.; Dobarro, Fernando
2014-03-01
The problem of the nonequivalence of the sets of equilibrium points and energy-Casimir extremal points, which occurs in the noncanonical Hamiltonian formulation of equations describing ideal fluid and plasma dynamics, is addressed in the context of the Euler equation for an incompressible inviscid fluid. The problem is traced to a Casimir deficit, where Casimir elements constitute the center of the Poisson algebra underlying the Hamiltonian formulation, and this leads to a study of singularities of the Poisson operator defining the Poisson bracket. The kernel of the Poisson operator, for this typical example of an infinite-dimensional Hamiltonian system for media in terms of Eulerian variables, is analyzed. For two-dimensional flows, a rigorously solvable system is formulated. The nonlinearity of the Euler equation makes the Poisson operator inhomogeneous on phase space (the function space of the state variable), and it is seen that this creates a singularity where the nullity of the Poisson operator (the "dimension" of the center) changes. The problem is an infinite-dimension generalization of the theory of singular differential equations. Singular Casimir elements stemming from this singularity are unearthed using a generalization of the functional derivative that occurs in the Poisson bracket.
On the Backward Stability of the Schwarzschild Black Hole Singularity
NASA Astrophysics Data System (ADS)
Fournodavlos, Grigorios
2016-08-01
We study the backwards-in-time stability of the Schwarzschild singularity from a dynamical PDE point of view. More precisely, considering a spacelike hypersurface {Σ_0} in the interior of the black hole region, tangent to the singular hypersurface {{r = 0}} at a single sphere, we study the problem of perturbing the Schwarzschild data on {Σ_0} and solving the Einstein vacuum equations backwards in time. We obtain a local backwards well-posedness result for small perturbations lying in certain weighted Sobolev spaces. No symmetry assumptions are imposed. The perturbed spacetimes all have a singularity at a "collapsed" sphere on {Σ_0}, where the leading asymptotics of the curvature and the metric match those of their Schwarzschild counterparts to a suitably high order. As in the Schwarzschild backward evolution, the pinched initial hypersurface {Σ_0} `opens up' instantly, becoming a regular spacelike (cylindrical) hypersurface. This result thus yields classes of examples of non-symmetric vacuum spacetimes, evolving forward-in-time from regular initial data, which form a Schwarzschild type singularity at a collapsed sphere. We rely on a precise asymptotic analysis of the Schwarzschild geometry near the singularity which turns out to be at the threshold that our energy methods can handle.
Inflationary cosmology leading to a soft type singularity
NASA Astrophysics Data System (ADS)
Brevik, I.; Obukhov, V. V.; Timoshkin, A. V.
2016-06-01
A remarkable property of modern cosmology is that it allows for a special case of symmetry, consisting in the possibility of describing the early-time acceleration (inflation) and the late-time acceleration using the same theoretical framework. In this paper, we consider various cosmological models corresponding to a generalized form for the equation of state for the fluid in a flat Friedmann-Robertson-Walker (FRW) universe, emphasizing cases where the so-called type IV singular inflation is encountered in the future. This is a soft (non-crushing) kind of singularity. Parameter values for an inhomogeneous equation of state leading to singular inflation are obtained. We present models for which there are two type IV singularities, the first corresponding to the end of the inflationary era and the second to a late-time event. We also study the correspondence between the theoretical slow-roll parameters leading to type IV singular inflation and the recent results observed by the Planck satellite.
Dynamics of learning near singularities in radial basis function networks.
Wei, Haikun; Amari, Shun-Ichi
2008-09-01
The radial basis function (RBF) networks are one of the most widely used models for function approximation in the regression problem. In the learning paradigm, the best approximation is recursively or iteratively searched for based on observed data (teacher signals). One encounters difficulties in such a process when two component basis functions become identical, or when the magnitude of one component becomes null. In this case, the number of the components reduces by one, and then the reduced component recovers as the learning process proceeds further, provided such a component is necessary for the best approximation. Strange behaviors, especially the plateau phenomena, have been observed in dynamics of learning when such reduction occurs. There exist singularities in the space of parameters, and the above reduction takes place at the singular regions. This paper focuses on a detailed analysis of the dynamical behaviors of learning near the overlap and elimination singularities in RBF networks, based on the averaged learning equation that is applicable to both on-line and batch mode learning. We analyze the stability on the overlap singularity by solving the eigenvalues of the Hessian explicitly. Based on the stability analysis, we plot the analytical dynamic vector fields near the singularity, which are then compared to those real trajectories obtained by a numeric method. We also confirm the existence of the plateaus in both batch and on-line learning by simulation.
Singularity detection by wavelet approach: application to electrocardiogram signal
NASA Astrophysics Data System (ADS)
Jalil, Bushra; Beya, Ouadi; Fauvet, Eric; Laligant, Olivier
2010-01-01
In signal processing, the region of abrupt changes contains the most of the useful information about the nature of the signal. The region or the points where these changes occurred are often termed as singular point or singular region. The singularity is considered to be an important character of the signal, as it refers to the discontinuity and interruption present in the signal and the main purpose of the detection of such singular point is to identify the existence, location and size of those singularities. Electrocardiogram (ECG) signal is used to analyze the cardiovascular activity in the human body. However the presence of noise due to several reasons limits the doctor's decision and prevents accurate identification of different pathologies. In this work we attempt to analyze the ECG signal with energy based approach and some heuristic methods to segment and identify different signatures inside the signal. ECG signal has been initially denoised by empirical wavelet shrinkage approach based on Steins Unbiased Risk Estimate (SURE). At the second stage, the ECG signal has been analyzed by Mallat approach based on modulus maximas and Lipschitz exponent computation. The results from both approaches has been discussed and important aspects has been highlighted. In order to evaluate the algorithm, the analysis has been done on MIT-BIH Arrhythmia database; a set of ECG data records sampled at a rate of 360 Hz with 11 bit resolution over a 10mv range. The results have been examined and approved by medical doctors.
Park, Ji Hyun; Choi, Yun Jung; Kim, Seon Ye; Lee, Jung-Eun; Sung, Ki Jung; Park, Sojung; Kim, Woo Sung; Song, Joon Seon; Choi, Chang-Min; Sung, Young Hoon; Rho, Jin Kyung; Lee, Jae Cheol
2016-01-01
Mutant-selective, 3rd-generation EGFR-TKIs were recently developed to control lung cancer cells harboring T790M-mediated resistance. However, the development of resistance to these novel drugs seems inevitable. Thus, we investigated the mechanism of acquired resistance to the mutant-selective EGFR-TKI WZ4002. We established five WZ4002-resistant cells, derived from cells harboring both EGFR and T790M mutations by long-term exposure to increasing doses of WZ4002. Compared with the parental cells, all resistant cells showed 10–100-folds higher resistance to WZ4002, as well as cross-resistance to other mutant-selective inhibitors. Among them, three resistant cells (HCC827/WR, PC-9/WR and H1975/WR) showed dependency on EGFR signaling, but two other cells (PC-9/GR/WR and PC-9/ER/WR) were not. Notably, insulin-like growth factor-1 receptor (IGF1R) was aberrantly activated in PC-9/GR/WR cells in phospho-receptor tyrosine kinase array, consistently accompanied by loss of IGF binding protein-3 (IGFBP3). Down-regulation of IGF1R by shRNA, as well as inhibition of IGF1R activity either by AG-1024 (a small molecule IGF1R inhibitor) or BI 836845 (a monoclonal anti-IGF1/2 blocking antibody), restored the sensitivity to WZ4002 both in vitro and xenograft. Taken together, these results suggest that activation of the IGF1R pathway associated with IGFBP3 loss can induce an acquired resistance to the mutant-selective EGFR-TKI, WZ4002. Therefore, a combined therapy of IGF1R inhibitors and mutant-selective EGFR-TKIs might be a viable treatment strategy for overcoming acquired resistance. PMID:26980747
Iris identification system based on Fourier coefficients and singular value decomposition
NASA Astrophysics Data System (ADS)
Somnugpong, Sawet; Phimoltares, Suphakant; Maneeroj, Saranya
2011-12-01
Nowadays, both personal identification and classification are very important. In order to identify the person for some security applications, physical or behavior-based characteristics of individuals with high uniqueness might be analyzed. Biometric becomes the mostly used in personal identification purpose. There are many types of biometric information currently used. In this work, iris, one kind of personal characteristics is considered because of its uniqueness and collectable. Recently, the problem of various iris recognition systems is the limitation of space to store the data in a variety of environments. This work proposes the iris recognition system with small-size of feature vector causing a reduction in space complexity term. For this experiment, each iris is presented in terms of frequency domain, and based on neural network classification model. First, Fast Fourier Transform (FFT) is used to compute the Discrete Fourier Coefficients of iris data in frequency domain. Once the iris data was transformed into frequency-domain matrix, Singular Value Decomposition (SVD) is used to reduce a size of the complex matrix to single vector. All of these vectors would be input for neural networks for the classification step. With this approach, the merit of our technique is that size of feature vector is smaller than that of other techniques with the acceptable level of accuracy when compared with other existing techniques.
Perturbative analysis of spectral singularities and their optical realizations
NASA Astrophysics Data System (ADS)
Mostafazadeh, Ali; Rostamzadeh, Saber
2012-08-01
We develop a perturbative method of computing spectral singularities of a Schrödinger operator defined by a general complex potential that vanishes outside a closed interval. These can be realized as zero-width resonances in optical gain media and correspond to a lasing effect that occurs at the threshold gain. Their time-reversed copies yield coherent perfect absorption of light that is also known as antilasing. We use our general results to establish the exactness of the nth-order perturbation theory for an arbitrary complex potential consisting of n delta functions, obtain an exact expression for the transfer matrix of these potentials, and examine spectral singularities of complex barrier potentials of arbitrary shape. In the context of optical spectral singularities, these correspond to inhomogeneous gain media.
Curved singular beams for three-dimensional particle manipulation.
Zhao, Juanying; Chremmos, Ioannis D; Song, Daohong; Christodoulides, Demetrios N; Efremidis, Nikolaos K; Chen, Zhigang
2015-01-01
For decades, singular beams carrying angular momentum have been a topic of considerable interest. Their intriguing applications are ubiquitous in a variety of fields, ranging from optical manipulation to photon entanglement, and from microscopy and coronagraphy to free-space communications, detection of rotating black holes, and even relativistic electrons and strong-field physics. In most applications, however, singular beams travel naturally along a straight line, expanding during linear propagation or breaking up in nonlinear media. Here, we design and demonstrate diffraction-resisting singular beams that travel along arbitrary trajectories in space. These curved beams not only maintain an invariant dark "hole" in the center but also preserve their angular momentum, exhibiting combined features of optical vortex, Bessel, and Airy beams. Furthermore, we observe three-dimensional spiraling of microparticles driven by such fine-shaped dynamical beams. Our findings may open up new avenues for shaped light in various applications.
Cosmological singularities in Born-Infeld determinantal gravity
NASA Astrophysics Data System (ADS)
Bouhmadi-López, Mariam; Chen, Che-Yu; Chen, Pisin
2014-12-01
The Born-Infeld determinantal gravity has been recently proposed as a way to smooth the big bang singularity. This theory is formulated on the Weitzenböck space-time and the teleparallel representation is used instead of the standard Riemannian representation. We find that although this theory is shown to be singularity free for a certain region of the parameter space in which the divergence of the Hubble rate in the high-energy regime is substituted by a de Sitter stage or a bounce in a Friedmann-Lemaître-Robertson-Walker universe, cosmological singularities—such as a big rip, big bang, big freeze, and sudden singularities—can emerge in other regions of the configuration space of the theory. We also show that all these singular events exist even though the universe is filled with a perfect fluid with a constant equation of state.
Singularity resolution in cosmologies using AdS/CFT
NASA Astrophysics Data System (ADS)
Ghosh, A.
2014-03-01
Singularities in general relativity are expected to be cured by a quantum theory of gravity. String theory is a prospective candidate for quantum gravity and holographic correspondences like AdS/CFT, that arise from string theory, might shed some light into the nature of singularities. While the theory of gravity might not be tractable near the singularity, the corresponding field theory might be well-behaved. We have come up with a model of cosmology, where curvatures become large at some time, thus, resembling a big crunch, but whose field theory dual remains well-behaved. Our analysis in the field theory indicates that we have a bouncing cosmology with a thermal distribution of radiation, and a possible formation of a small black hole after the bounce.
Curved singular beams for three-dimensional particle manipulation.
Zhao, Juanying; Chremmos, Ioannis D; Song, Daohong; Christodoulides, Demetrios N; Efremidis, Nikolaos K; Chen, Zhigang
2015-01-01
For decades, singular beams carrying angular momentum have been a topic of considerable interest. Their intriguing applications are ubiquitous in a variety of fields, ranging from optical manipulation to photon entanglement, and from microscopy and coronagraphy to free-space communications, detection of rotating black holes, and even relativistic electrons and strong-field physics. In most applications, however, singular beams travel naturally along a straight line, expanding during linear propagation or breaking up in nonlinear media. Here, we design and demonstrate diffraction-resisting singular beams that travel along arbitrary trajectories in space. These curved beams not only maintain an invariant dark "hole" in the center but also preserve their angular momentum, exhibiting combined features of optical vortex, Bessel, and Airy beams. Furthermore, we observe three-dimensional spiraling of microparticles driven by such fine-shaped dynamical beams. Our findings may open up new avenues for shaped light in various applications. PMID:26166011
Analytic evolution of singular distribution amplitudes in QCD
NASA Astrophysics Data System (ADS)
Radyushkin, A. V.; Tandogan, A.
2014-04-01
We describe a method of analytic evolution of distribution amplitudes (DAs) that have singularities, such as nonzero values at the end points of the support region, jumps at some points inside the support region and cusps. We illustrate the method by applying it to the evolution of a flat (constant) DA and antisymmetric flat DA, and then use the method for evolution of the two-photon generalized distribution amplitude. Our approach has advantages over the standard method of expansion in Gegenbauer polynomials, which requires an infinite number of terms in order to accurately reproduce functions in the vicinity of singular points, and over a straightforward iteration of an initial distribution with evolution kernel. The latter produces logarithmically divergent terms at each iteration, while in our method the logarithmic singularities are summed from the start, which immediately produces a continuous curve, with only one or two iterations needed afterwards in order to get rather precise results.
The Hamiltonian property of the flow of singular trajectories
NASA Astrophysics Data System (ADS)
Lokutsievskiy, L. V.
2014-03-01
Pontryagin's maximum principle reduces optimal control problems to the investigation of Hamiltonian systems of ordinary differential equations with discontinuous right-hand side. An optimal synthesis is the totality of solutions to this system with a fixed terminal (or initial) condition, which fill a region in the phase space one-to-one. In the construction of optimal synthesis, singular trajectories that go along the discontinuity surface N of the right-hand side of the Hamiltonian system of ordinary differential equations, are crucial. The aim of the paper is to prove that the system of singular trajectories makes up a Hamiltonian flow on a submanifold of N. In particular, it is proved that the flow of singular trajectories in the problem of control of the magnetized Lagrange top in a variable magnetic field is completely Liouville integrable and can be embedded in the flow of a smooth superintegrable Hamiltonian system in the ambient space. Bibliography: 17 titles.
Analytic Evolution of Singular Distribution Amplitudes in QCD
Radyushkin, Anatoly V.; Tandogan Kunkel, Asli
2014-03-01
We describe a method of analytic evolution of distribution amplitudes (DA) that have singularities, such as non-zero values at the end-points of the support region, jumps at some points inside the support region and cusps. We illustrate the method by applying it to the evolution of a flat (constant) DA, anti-symmetric at DA and then use it for evolution of the two-photon generalized distribution amplitude. Our approach has advantages over the standard method of expansion in Gegenbauer polynomials, which requires infinite number of terms in order to accurately reproduce functions in the vicinity of singular points, and over a straightforward iteration of an initial distribution with evolution kernel. The latter produces logarithmically divergent terms at each iteration, while in our method the logarithmic singularities are summed from the start, which immediately produces a continuous curve, with only one or two iterations needed afterwards in order to get rather precise results.
Optimal singular control with applications to trajectory optimization
NASA Technical Reports Server (NTRS)
Vinh, N. X.
1977-01-01
A comprehensive discussion of the problem of singular control is presented. Singular control enters an optimal trajectory when the so called switching function vanishes identically over a finite time interval. Using the concept of domain of maneuverability, the problem of optical switching is analyzed. Criteria for the optimal direction of switching are presented. The switching, or junction, between nonsingular and singular subarcs is examined in detail. Several theorems concerning the necessary, and also sufficient conditions for smooth junction are presented. The concepts of quasi-linear control and linearized control are introduced. They are designed for the purpose of obtaining approximate solution for the difficult Euler-Lagrange type of optimal control in the case where the control is nonlinear.
Curved singular beams for three-dimensional particle manipulation
Zhao, Juanying; Chremmos, Ioannis D.; Song, Daohong; Christodoulides, Demetrios N.; Efremidis, Nikolaos K.; Chen, Zhigang
2015-01-01
For decades, singular beams carrying angular momentum have been a topic of considerable interest. Their intriguing applications are ubiquitous in a variety of fields, ranging from optical manipulation to photon entanglement, and from microscopy and coronagraphy to free-space communications, detection of rotating black holes, and even relativistic electrons and strong-field physics. In most applications, however, singular beams travel naturally along a straight line, expanding during linear propagation or breaking up in nonlinear media. Here, we design and demonstrate diffraction-resisting singular beams that travel along arbitrary trajectories in space. These curved beams not only maintain an invariant dark “hole” in the center but also preserve their angular momentum, exhibiting combined features of optical vortex, Bessel, and Airy beams. Furthermore, we observe three-dimensional spiraling of microparticles driven by such fine-shaped dynamical beams. Our findings may open up new avenues for shaped light in various applications. PMID:26166011
On the regularizability of the big bang singularity
NASA Astrophysics Data System (ADS)
Belbruno, Edward
2013-01-01
The singularity for the big bang state can be represented using the generalized anisotropic Friedmann equation, resulting in a system of differential equations in a central force field. We study the regularizability of this singularity as a function of a parameter, the equation of state, w. We prove that for w > 1 it is regularizable only for w satisfying relative prime number conditions, and for w ≤ 1 it can always be regularized. This is done by using a McGehee transformation, usually applied in the three and four-body problems. This transformation blows up the singularity into an invariant manifold. The relationship of this result to other cosmological models is briefly discussed.
Statistical Analysis of the Ionosphere based on Singular Value Decomposition
NASA Astrophysics Data System (ADS)
Demir, Uygar; Arikan, Feza; Necat Deviren, M.; Toker, Cenk
2016-07-01
Ionosphere is made up of a spatio-temporally varying trend structure and secondary variations due to solar, geomagnetic, gravitational and seismic activities. Hence, it is important to monitor the ionosphere and acquire up-to-date information about its state in order both to better understand the physical phenomena that cause the variability and also to predict the effect of the ionosphere on HF and satellite communications, and satellite-based positioning systems. To charaterise the behaviour of the ionosphere, we propose to apply Singular Value Decomposition (SVD) to Total Electron Content (TEC) maps obtained from the TNPGN-Active (Turkish National Permanent GPS Network) CORS network. TNPGN-Active network consists of 146 GNSS receivers spread over Turkey. IONOLAB-TEC values estimated from each station are spatio-temporally interpolated using a Universal Kriging based algorithm with linear trend, namely IONOLAB-MAP, with very high spatial resolution. It is observed that the dominant singular value of TEC maps is an indicator of the trend structure of the ionosphere. The diurnal, seasonal and annual variability of the most dominant value is the representation of solar effect on ionosphere in midlatitude range. Secondary and smaller singular values are indicators of secondary variation which can have significance especially during geomagnetic storms or seismic disturbances. The dominant singular values are related to the physical basis vectors where ionosphere can be fully reconstructed using these vectors. Therefore, the proposed method can be used both for the monitoring of the current state of a region and also for the prediction and tracking of future states of ionosphere using singular values and singular basis vectors. This study is supported by by TUBITAK 115E915 and Joint TUBITAK 114E092 and AS CR14/001 projects.
The Force Singularity for Partially Immersed Parallel Plates
NASA Astrophysics Data System (ADS)
Bhatnagar, Rajat; Finn, Robert
2016-05-01
In earlier work, we provided a general description of the forces of attraction and repulsion, encountered by two parallel vertical plates of infinite extent and of possibly differing materials, when partially immersed in an infinite liquid bath and subject to surface tension forces. In the present study, we examine some unusual details of the exotic behavior that can occur at the singular configuration separating infinite rise from infinite descent of the fluid between the plates, as the plates approach each other. In connection with this singular behavior, we present also some new estimates on meniscus height details.
Asymptotics of action variables near semi-toric singularities
NASA Astrophysics Data System (ADS)
Wacheux, Christophe
2015-12-01
The presence of focus-focus singularities in semi-toric integrables Hamiltonian systems is one of the reasons why there cannot exist global Action-Angle coordinates on such systems. At focus-focus critical points, the Liouville-Arnold-Mineur theorem does not apply. In particular, the affine structure of the image of the moment map around has non-trivial monodromy. In this article, we establish that the singular behavior and the multi-valuedness of the Action integrals is given by a complex logarithm. This extends a previous result by San Vũ Ngọc to any dimension. We also calculate the monodromy matrix for these systems.
18. Simulations of Generic Singularities in Harmonic Coordinates
NASA Astrophysics Data System (ADS)
Garfinkle, David
This paper presents both a numerical method for general relativity and an application of that method. The method involves the use of harmonic coordinates in a 3+1 code to evolve the Einstein equations with scalar field matter. In such coordinates, the terms in Einstein's equations with the highest number of derivatives take a form similar to that of the wave equation. The application is an exploration of the generic approach to the singularity for this type of matter. The preliminary results indicate that the dynamics as one approaches the singularity is locally the dynamics of the Kasner spacetimes.
Velocity Dominated Singularities in the Cheese Slice Universe
NASA Astrophysics Data System (ADS)
Giang, Dan; Dyer, Charles C.
We investigate the properties of space-times resulting from matching together exact solutions using the Darmois matching conditions. In particular, we focus on the asymptotically velocity-term dominated property (AVTD). We propose a criterion that can be used to test if a space-time constructed from a matching can be considered AVTD. Using the "cheese slice" universe as an example, we show that a space-time constructed from a such a matching can inherit the AVTD property from the original space-times. Furthermore the singularity resulting from this particular matching is an AVTD singularity.
The effect of singular potentials on the harmonic oscillator
Filgueiras, C.; Silva, E.O.; Oliveira, W.; Moraes, F.
2010-11-15
We address the problem of a quantum particle moving under interactions presenting singularities. The self-adjoint extension approach is used to guarantee that the Hamiltonian is self-adjoint and to fix the choice of boundary conditions. We specifically look at the harmonic oscillator added of either a {delta}-function potential or a Coulomb potential (which is singular at the origin). The results are applied to Landau levels in the presence of a topological defect, the Calogero model and to the quantum motion on the noncommutative plane.
Photonic analog of a van Hove singularity in metamaterials
NASA Astrophysics Data System (ADS)
Cortes, Cristian L.; Jacob, Zubin
2013-07-01
We introduce the photonic analog of electronic van Hove singularities (VHS) in artificial media (metamaterials) with hyperbolic dispersion. Unlike photonic and electronic crystals, the VHS in metamaterials are unrelated to the underlying periodicity and occur due to slow-light modes in the structure. We show that the VHS characteristics are manifested in the near-field local density of optical states in spite of the losses, dispersion, and finite unit-cell size of the hyperbolic metamaterial. Finally, we show that this work should lead to quantum, thermal, nanolasing, and biosensing applications of van Hove singularities in hyperbolic metamaterials achievable by current fabrication technology.
Approximate analytic solutions for singular non-linear oscillators
NASA Technical Reports Server (NTRS)
Bota, K. B.; Mickens, R. E.
1984-01-01
Mickens (1981, 1984) has considered analytic techniques for obtaining approximate solutions to one-dimensional nonlinear oscillatory systems x(double-dot) + x = lambda f(x, x/dot/, lambda) where lambda is a small positive parameter and f is a nonlinear polynomial function of its arguments. However, in certain cases there is interest in the analysis of physical systems for which the nonlinear function f(x, x/dot/, lambda) is singular for finite values of x or x(dot). The present investigation is concerned with the use of existing approximate analytic schemes to obtain solutions to singular nonlinear oscillatory differential equations.
Design of a singularity-free articulated arm subassembly
Remis, S.J.; Stanisic, M.M. . Aerospace and Mechanical Engineering Dept.)
1993-12-01
Adding a redundant degree of freedom to the shoulder pointing system complex of an articulated arm subassembly makes it possible to achieve a maximal workspace that is free of singularities. This paper derives a functional constraint between three of the four joints of this new type of arm, achieving a singularity-free workspace encompassing the entire reachable volume between the maximal- and minimal-reach surfaces. The large volume of dexterous workspace is verified by animation of the resulting arm design. Graphical results from the animation are presented comparing the dexterous workspace of this new arm to that of the standard nonredundant articulated arm subassembly such as found in the Puma manipulator.
Surface singularities in Eddington-inspired Born-Infeld gravity.
Pani, Paolo; Sotiriou, Thomas P
2012-12-21
Eddington-inspired Born-Infeld gravity was recently proposed as an alternative to general relativity that offers a resolution of spacetime singularities. The theory differs from Einstein's gravity only inside matter due to nondynamical degrees of freedom, and it is compatible with all current observations. We show that the theory is reminiscent of Palatini f(R) gravity and that it shares the same pathologies, such as curvature singularities at the surface of polytropic stars and unacceptable Newtonian limit. This casts serious doubt on its viability.
Surface singularities in Eddington-inspired Born-Infeld gravity.
Pani, Paolo; Sotiriou, Thomas P
2012-12-21
Eddington-inspired Born-Infeld gravity was recently proposed as an alternative to general relativity that offers a resolution of spacetime singularities. The theory differs from Einstein's gravity only inside matter due to nondynamical degrees of freedom, and it is compatible with all current observations. We show that the theory is reminiscent of Palatini f(R) gravity and that it shares the same pathologies, such as curvature singularities at the surface of polytropic stars and unacceptable Newtonian limit. This casts serious doubt on its viability. PMID:23368444
Do Men Vary More than Women in Personality? A Study in 51 Cultures
Borkenau, Peter; McCrae, Robert R.; Terracciano, Antonio
2013-01-01
Do men vary more than women in personality? Evolutionary, genetic, and cultural arguments suggest that hypothesis. In this study we tested it using 12,156 college student raters from 51 cultures who described a person they knew well on the 3rd-person version of the Revised NEO Personality Inventory. In most cultures, male targets varied more than female targets, and ratings by female informants varied more than ratings by male informants, which may explain why higher variances for men are not found in self-reports. Variances were higher in more developed, and effects of target sex were stronger in more individualistic societies. It seems that individualistic cultures enable a less restricted expression of personality, resulting in larger variances and particularly so among men. PMID:23559686
Do Men Vary More than Women in Personality? A Study in 51 Cultures.
Borkenau, Peter; McCrae, Robert R; Terracciano, Antonio
2013-04-01
Do men vary more than women in personality? Evolutionary, genetic, and cultural arguments suggest that hypothesis. In this study we tested it using 12,156 college student raters from 51 cultures who described a person they knew well on the 3rd-person version of the Revised NEO Personality Inventory. In most cultures, male targets varied more than female targets, and ratings by female informants varied more than ratings by male informants, which may explain why higher variances for men are not found in self-reports. Variances were higher in more developed, and effects of target sex were stronger in more individualistic societies. It seems that individualistic cultures enable a less restricted expression of personality, resulting in larger variances and particularly so among men. PMID:23559686
... person has a long-term pattern of behaviors, emotions, and thoughts that is very different from his or her culture's expectations. These behaviors interfere with the person's ability to function in relationships, work, or other settings.
Personality disorders are a group of mental illnesses. They involve long-term patterns of thoughts and behaviors ... serious problems with relationships and work. People with personality disorders have trouble dealing with everyday stresses and ...
A Connection between Singular Stochastic Control and Optimal Stopping
Espen Benth, Fred Reikvam, Kristin
2003-12-15
We show that the value function of a singular stochastic control problem is equal to the integral of the value function of an associated optimal stopping problem. The connection is proved for a general class of diffusions using the method of viscosity solutions.
Lidar signal de-noising by singular value decomposition
NASA Astrophysics Data System (ADS)
Wang, Huanxue; Liu, Jianguo; Zhang, Tianshu
2014-11-01
Signal de-noising remains an important problem in lidar signal processing. This paper presents a de-noising method based on singular value decomposition. Experimental results on lidar simulated signal and real signal show that the proposed algorithm not only improves the signal-to-noise ratio effectively, but also preserves more detail information.
Wigner Measure Propagation and Conical Singularity for General Initial Data
NASA Astrophysics Data System (ADS)
Fermanian-Kammerer, Clotilde; Gérard, Patrick; Lasser, Caroline
2013-07-01
We study the evolution of Wigner measures of a family of solutions of a Schrödinger equation with a scalar potential displaying a conical singularity. Under a genericity assumption, classical trajectories exist and are unique, thus the question of the propagation of Wigner measures along these trajectories becomes relevant. We prove the propagation for general initial data.
On Resolutions of Cosmological Singularities in Higher-Spin Gravity
NASA Astrophysics Data System (ADS)
Burrington, Benjamin; Pando Zayas, Leopoldo; Rombes, Nicholas
2014-03-01
Gravity in three dimensions is simpler than in four, due to the lack of gravitational waves, and can be recast as a Chern-Simons theory. In this context, it is straightforward to generalize Einstein's gravity, with or without cosmological constant, by changing the gauge group. Using this, we study the resolution of certain cosmological singularities, and extend the singularity resolution scheme proposed by Krishnan and Roy. We discuss the resolution of a big-bang singularity in the case of gravity coupled to a spin-4 field realized as Chern-Simons theory with gauge group SL (4 , C) . We show the existence of gauge transformations that do not change the holonomy of the Chern-Simons gauge potential and lead to metrics without the initial singularity. We argue that such transformations always exist in the context of gravity coupled to a spin-N field when described by Chern-Simons with gauge group SL (N , C) . This work was supported by the DOE under grant DE-FG02-95ER40899, a research grant from Troy University, and the Honors Summer Fellowship at the University of Michigan.
Faddeev-Jackiw quantization of non-autonomous singular systems
NASA Astrophysics Data System (ADS)
Belhadi, Zahir; Bérard, Alain; Mohrbach, Hervé
2016-10-01
We extend the quantization à la Faddeev-Jackiw for non-autonomous singular systems. This leads to a generalization of the Schrödinger equation for those systems. The method is exemplified by the quantization of the damped harmonic oscillator and the relativistic particle in an external electromagnetic field.
Non-singular dislocation loops in gradient elasticity
NASA Astrophysics Data System (ADS)
Lazar, Markus
2012-04-01
Using gradient elasticity, we give in this Letter the non-singular fields produced by arbitrary dislocation loops in isotropic media. We present the ‘modified’ Mura, Peach-Koehler and Burgers formulae in the framework of gradient elasticity theory.
Pulsar Magnetospheres: Variation Principle, Singularities, and Estimate of Power
NASA Astrophysics Data System (ADS)
Gruzinov, Andrei
2006-08-01
We formulate a variation principle for the force-free magnetosphere of an inclined pulsar: E+Ω b.dot M (where E and M are electromagnetic energy and angular momentum and Ω is the angular velocity of the star) is stationary under isotopological variations of the magnetic field and arbitrary variations of the electric field. The variation principle gives the reason for the existence and proves the local stability of singular current layers along magnetic separatrices. Magnetic field lines of inclined pulsar magnetospheres lie on magnetic surfaces and do have magnetic separatrices. In the framework of the isotopological variation principle, inclined magnetospheres are expected to be simple deformations of the axisymmetric pulsar magnetosphere. A singular line should exist on the light cylinder, where the inner separatrix terminates and the outer separatrix emanates. The electromagnetic field should have an inverse square root singularity near the singular line inside the inner magnetic separatrix. The large-distance asymptotic solution is calculated and used to estimate the pulsar power, L~c-3μ2Ω4 for spin-dipole inclinations <~30°.
Optimal singular control with applications to trajectory optimization
NASA Technical Reports Server (NTRS)
Vinh, N. X.
1979-01-01
The switching conditions are expressed explicitly in terms of the derivatives of the Hamiltonians at the two ends of the switching. A new expression of the Kelley-Contensou necessary condition for the optimality of a singular arc is given. Some examples illustrating the application of the theory are presented.
Quantum jump from singularity to outside of black hole
NASA Astrophysics Data System (ADS)
Dündar, Furkan Semih; Hajian, Kamal
2016-02-01
Considering the role of black hole singularity in quantum evolution, a resolution to the firewall paradox is presented. It is emphasized that if an observer has the singularity as a part of his spacetime, then the semi-classical evolution would be non-unitary as viewed by him. Specifically, a free-falling observer inside the black hole would have a Hilbert space with non-unitary evolution; a quantum jump for particles encountering the singularity to outside of the horizon as late Hawking radiations. The non-unitarity in the jump resembles the one in collapse of wave function, but preserves entanglements. Accordingly, we elaborate the first postulate of black hole complementarity: freely falling observers who pass through the event horizon would have non-unitary evolution, while it does not have physically measurable effects for them. Besides, no information would be lost in the singularity. Taking the modified picture into account, the firewall paradox can be resolved, respecting No Drama. A by-product of our modification is that roughly half of the entropy of the black hole is released close to the end of evaporation in the shape of very hot Hawking radiation.
Singular perturbations in shape optimization for the Dirichlet Laplacian
NASA Astrophysics Data System (ADS)
Nazarov, Serguei A.; Sokolowski, Jan
2005-04-01
A shape optimization problem is considered for the Dirichlet Laplacian. Asymptotic analysis is used in order to characterise the optimal shapes which are finally given by a singular perturbation of the smooth initial domain. To cite this article: S.A. Nazarov, J. Sokolowski, C. R. Mecanique 333 (2005).
Print to Paint: Breaking Away from Singular Images
ERIC Educational Resources Information Center
Alexander, Kristi
2010-01-01
Each fall, the author presents a printmaking unit, starting with simple techniques such as rubbings, stamping and stenciling. In this article, the author describes a linoleum printmaking lesson wherein students are challenged to break away from singular images of peace signs and initials, and create illustrative plates that could communicate a…
Formation and morphological transformation of polarization singularities: hunting the monstar
NASA Astrophysics Data System (ADS)
Kumar, Vijay; Philip, Geo M.; Viswanathan, Nirmal K.
2013-04-01
The theoretical formalism and experimental measurements to form and transform between the three morphologies of the polarization singular patterns—star, lemon and monstar—are presented here. The monstar is statistically rare in isotropic random fields but its controllable realization is achieved by tuning the field anisotropy in three-beam interference.
Singularity classification as a design tool for multiblock grids
NASA Technical Reports Server (NTRS)
Jones, Alan K.
1992-01-01
A major stumbling block in interactive design of 3-D multiblock grids is the difficulty of visualizing the design as a whole. One way to make this visualization task easier is to focus, at least in early design stages, on an aspect of the grid which is inherently easy to present graphically, and to conceptualize mentally, namely the nature and location of singularities in the grid. The topological behavior of a multiblock grid design is determined by what happens at its edges and vertices. Only a few of these are in any way exceptional. The exceptional behaviors lie along a singularity graph, which is a 1-D construct embedded in 3-D space. The varieties of singular behavior are limited enough to make useful symbology on a graphics device possible. Furthermore, some forms of block design manipulation that appear appropriate to the early conceptual-modeling phase can be accomplished on this level of abstraction. An overview of a proposed singularity classification scheme and selected examples of corresponding manipulation techniques is presented.
Singular Behaviour of the Electrodynamic Fields of an Oscillating Dipole
ERIC Educational Resources Information Center
Leung, P. T.
2008-01-01
The singularity of the exact electromagnetic fields is derived to include the "source terms" for harmonically oscillating electric (and magnetic) dipoles, so that the fields will be consistent with the full Maxwell equations with a source. It is shown explicitly, as somewhat expected, that the same [delta]-function terms for the case of static…
NASA Astrophysics Data System (ADS)
Osete, M. L.; Chauvin, A.; Catanzariti, G.; Jimeno, A.; Campuzano, S. A.; Benito-Batanero, J. P.; Tabernero-Galán, C.; Roperch, P.
2016-11-01
Variations of geomagnetic field in the Iberian Peninsula prior to roman times are poorly constrained. Here we report new archaeomagnetic results from four ceramic collections and two combustion structures recovered in two pre-roman (celtiberic) archaeological sites in central Spain. The studied materials have been dated by archaeological evidences and supported by five radiocarbon dates. Rock magnetic experiments indicate that the characteristic remanent manetization (ChRM) is carried by a low coercivity magnetic phase with Curie temperatures of 530-575 °C, most likely Ti-poor titanomagnetite/titanomaghemite. Archaeointensity determinations were carried out by using the classical Thellier-Thellier protocol including tests and corrections for magnetic anisotropy and cooling rate dependency. Two magnetic behaviours were depicted during the laboratory treatment. Black potsherds and poor heated samples from the kilns, presented two magnetization components, alterations or curved Arai plots and were therefore rejected. In contrast, well heated specimens (red ceramic fragments and well heated samples from the kilns) show one single well defined component of magnetization going through the origin and linear Arai plots providing successful archaeointensity determinations. The effect of anisotropy of the thermoremanent magnetization (ATRM) on paleointensity analysis was systematically investigated obtaining very high ATRM corrections on fine pottery specimens. In some cases, differences between the uncorrected and ATRM corrected paleointensity values reached up to 86 %. The mean intensity values obtained from three selected set of samples were 64.3 ± 5.8 μT; 56.8 ± 3.8 and 56.7 ± 4.6 μT (NUS2, CI2 and CIA, respectively), which contribute to better understand the evolution of the palaeofield intensity in central Iberia during the 3rd-1st centuries BC. The direction of the field at first century BC has also been determined from oriented samples from CIA kilns (D = 357
Characterization of peak flow events with local singularity method
NASA Astrophysics Data System (ADS)
Cheng, Q.; Li, L.; Wang, L.
2009-07-01
Three methods, return period, power-law frequency plot (concentration-area) and local singularity index, are introduced in the paper for characterizing peak flow events from river flow data for the past 100 years from 1900 to 2000 recorded at 25 selected gauging stations on rivers in the Oak Ridges Moraine (ORM) area, Canada. First a traditional method, return period, was applied to the maximum annual river flow data. Whereas the Pearson III distribution generally fits the values, a power-law frequency plot (C-A) on the basis of self-similarity principle provides an effective mean for distinguishing "extremely" large flow events from the regular flow events. While the latter show a power-law distribution, about 10 large flow events manifest departure from the power-law distribution and these flow events can be classified into a separate group most of which are related to flood events. It is shown that the relation between the average water releases over a time period after flow peak and the time duration may follow a power-law distribution. The exponent of the power-law or singularity index estimated from this power-law relation may be used to characterize non-linearity of peak flow recessions. Viewing large peak flow events or floods as singular processes can anticipate the application of power-law models not only for characterizing the frequency distribution of peak flow events, for example, power-law relation between the number and size of floods, but also for describing local singularity of processes such as power-law relation between the amount of water released versus releasing time. With the introduction and validation of singularity of peak flow events, alternative power-law models can be used to depict the recession property as well as other types of non-linear properties.
Perfect fluid tori orbiting Kehagias-Sfetsos naked singularities
NASA Astrophysics Data System (ADS)
Stuchlík, Z.; Pugliese, D.; Schee, J.; Kučáková, H.
2015-09-01
We construct perfect fluid tori in the field of the Kehagias-Sfetsos (K-S) naked singularities. These are spherically symmetric vacuum solutions of the modified Hořava quantum gravity, characterized by a dimensionless parameter ω M^2, combining the gravitational mass parameter M of the spacetime with the Hořava parameter ω reflecting the role of the quantum corrections. In dependence on the value of ω M^2, the K-S naked singularities demonstrate a variety of qualitatively different behavior of their circular geodesics that is fully reflected in the properties of the toroidal structures, demonstrating clear distinction to the properties of the torii in the Schwarzschild spacetimes. In all of the K-S naked singularity spacetimes the tori are located above an "antigravity" sphere where matter can stay in a stable equilibrium position, which is relevant for the stability of the orbiting fluid toroidal accretion structures. The signature of the K-S naked singularity is given by the properties of marginally stable tori orbiting with the uniform distribution of the specific angular momentum of the fluid, l= const. In the K-S naked singularity spacetimes with ω M^2 > 0.2811, doubled tori with the same l= const can exist; mass transfer between the outer torus and the inner one is possible under appropriate conditions, while only outflow to the outer space is allowed in complementary conditions. In the K-S spacetimes with ω M^2 < 0.2811, accretion from cusped perfect fluid tori is not possible due to the non-existence of unstable circular geodesics.
The Friedmann-Lemaître-Robertson-Walker Big Bang Singularities are Well Behaved
NASA Astrophysics Data System (ADS)
Stoica, Ovidiu Cristinel
2016-01-01
We show that the Big Bang singularity of the Friedmann-Lemaître-Robertson-Walker model does not raise major problems to General Relativity. We prove a theorem showing that the Einstein equation can be written in a non-singular form, which allows the extension of the spacetime before the Big Bang. The physical interpretation of the fields used is discussed. These results follow from our research on singular semi-Riemannian geometry and singular General Relativity.
Singularities, trapped sets, and cosmic censorship in asymptotically flat space-times
Krolak, A. ); Rudnicki, W. )
1993-01-01
We show that space-time is future asymptotically predictable from a regular partial Cauchy provided that singularities are causally preceded by trapped sets. Future asymptotic predictability is a formal statement of cosmic censorship in asymptotically flat space-times. A regular partial Cauchy surface means that singularities in gravitational collapse can arise only from regular initial data. Our result confirms a supposition by Hawking that singularities forced by singularity theorems cannot be naked.
The analysis of optimal singular controls for SEIR model of tuberculosis
NASA Astrophysics Data System (ADS)
Marpaung, Faridawaty; Rangkuti, Yulita M.; Sinaga, Marlina S.
2014-12-01
The optimally of singular control for SEIR model of Tuberculosis is analyzed. There are controls that correspond to time of the vaccination and treatment schedule. The optimally of singular control is obtained by differentiate a switching function of the model. The result shows that vaccination and treatment control are singular.
Naked singularities in non-self-similar gravitational collapse of radiation shells
Joshi, P.S.; Dwivedi, I.H. )
1992-03-15
Non-self-similar gravitational collapse of imploding radiation is shown to give rise to a strong curvature naked singularity. The conditions are specified for the singularity to be globally naked and the strength of the same is examined along nonspacelike curves and along all the families of nonspacelike geodesics terminating at the singularity in the past.
A Generalized Method of Image Analysis from an Intercorrelation Matrix which May Be Singular.
ERIC Educational Resources Information Center
Yanai, Haruo; Mukherjee, Bishwa Nath
1987-01-01
This generalized image analysis method is applicable to singular and non-singular correlation matrices (CMs). Using the orthogonal projector and a weaker generalized inverse matrix, image and anti-image covariance matrices can be derived from a singular CM. (SLD)
Personality traits and personality disorders.
Deary, I J; Peter, A; Austin, E; Gibson, G
1998-11-01
The structure of personality disorder traits was examined in a sample of 400 undergraduates who completed the personality disorder questionnaire from the Structured Clinical Interview for DSM-III-R (SCID-II). The relations between personality disorder and normal personality traits indexed by the Eysenck Personality Questionnaire-Revised (EPQ-R) were examined. The three-cluster model of personality traits--as described in the DSM scheme--found equivocal support. Exploratory principal components analysis and confirmatory factor analysis found four broad factors of personality disorder that overlapped with normal personality traits: an asthenic factor related to neuroticism; an antisocial factor associated with psychoticism; an asocial factor linked to introversion-extraversion; and an anankastic (obsessive-compulsive) factor. There is growing agreement about the number and type of broad personality disorder dimensions; similar dimensions may be found in clinical and non-clinical samples, suggesting that those people with personality disorders differ quantitatively rather than qualitatively from others; and there is substantial overlap between normal and abnormal personality dimensions.
Numerical generation of a polarization singularity array with modulated amplitude and phase.
Ye, Dong; Peng, Xinyu; Zhao, Qi; Chen, Yanru
2016-09-01
A point having no defined polarized ellipse azimuthal angle (circularly polarized) in a space-variant vector field is called a polarization singularity, and it has three types: Lemon, Monstar, and Star. Recently, the connection of polarization singularities has been performed. Inspired by this, we conduct a numerical generation of a polarization singularity array. Our method is based on two orthogonal linearly polarized light beams with modulated amplitude and phase. With appropriate distribution functions of amplitudes and phases we can control the polarized states of polarization singularities, which offer a possibility to simulate a polarization singularity array. PMID:27607491
The singularities, forces transmission index and mechanism selfblocking
NASA Astrophysics Data System (ADS)
Duca, C.; Buium, F.
2016-08-01
The paper represents a synthesis of the most representative results obtained by authors, along their researches in the field of mechanism singularities, forces transmission quality in mechanisms and self-blocking phenomenon. Our research is based on the idea that mechanism critical positions are a consequence of critical configurations in the component structural groups. At its turn, the critical configurations are noticed when the mathematical model of the kinematics and statics without friction, is affected by singularities. Thus, we have presented in the paper, the case of the principal structural groups, and we have established the critical configuration, the calculus formula of the configuration parameter and the existence conditions of the configuration (real solutions in the position problem).
Asymptotically AdS spacetimes with a timelike Kasner singularity
NASA Astrophysics Data System (ADS)
Ren, Jie
2016-07-01
Exact solutions to Einstein's equations for holographic models are presented and studied. The IR geometry has a timelike cousin of the Kasner singularity, which is the less generic case of the BKL (Belinski-Khalatnikov-Lifshitz) singularity, and the UV is asymptotically AdS. This solution describes a holographic RG flow between them. The solution's appearance is an interpolation between the planar AdS black hole and the AdS soliton. The causality constraint is always satisfied. The entanglement entropy and Wilson loops are discussed. The boundary condition for the current-current correlation function and the Laplacian in the IR is examined. There is no infalling wave in the IR, but instead, there is a normalizable solution in the IR. In a special case, a hyperscaling-violating geometry is obtained after a dimensional reduction.
Potentially singular solutions of the 3D axisymmetric Euler equations
Luo, Guo; Hou, Thomas Y.
2014-01-01
The question of finite-time blowup of the 3D incompressible Euler equations is numerically investigated in a periodic cylinder with solid boundaries. Using rotational symmetry, the equations are discretized in the (2D) meridian plane on an adaptive (moving) mesh and is integrated in time with adaptively chosen time steps. The vorticity is observed to develop a ring-singularity on the solid boundary with a growth proportional to ∼(ts − t)−2.46, where ts ∼ 0.0035056 is the estimated singularity time. A local analysis also suggests the existence of a self-similar blowup. The simulations stop at τ2 = 0.003505 at which time the vorticity amplifies by more than (3 × 108)-fold and the maximum mesh resolution exceeds (3 × 1012)2. The vorticity vector is observed to maintain four significant digits throughout the computations. PMID:25157172
Vortex equations: Singularities, numerical solution, and axisymmetric vortex breakdown
NASA Technical Reports Server (NTRS)
Bossel, H. H.
1972-01-01
A method of weighted residuals for the computation of rotationally symmetric quasi-cylindrical viscous incompressible vortex flow is presented and used to compute a wide variety of vortex flows. The method approximates the axial velocity and circulation profiles by series of exponentials having (N + 1) and N free parameters, respectively. Formal integration results in a set of (2N + 1) ordinary differential equations for the free parameters. The governing equations are shown to have an infinite number of discrete singularities corresponding to critical values of the swirl parameters. The computations point to the controlling influence of the inner core flow on vortex behavior. They also confirm the existence of two particular critical swirl parameter values: one separates vortex flow which decays smoothly from vortex flow which eventually breaks down, and the second is the first singularity of the quasi-cylindrical system, at which point physical vortex breakdown is thought to occur.
Wentzel-Bardeen singularity in coupled Luttinger liquids: Transport properties
Martin, T.
1994-08-26
The recent progress on 1 D interacting electrons systems and their applications to study the transport properties of quasi one dimensional wires is reviewed. We focus on strongly correlated elections coupled to low energy acoustic phonons in one dimension. The exponents of various response functions are calculated, and their striking sensitivity to the Wentzel-Bardeen singularity is discussed. For the Hubbard model coupled to phonons the equivalent of a phase diagram is established. By increasing the filling factor towards half filling the WB singularity is approached. This in turn suppresses antiferromagnetic fluctuations and drives the system towards the superconducting regime, via a new intermediate (metallic) phase. The implications of this phenomenon on the transport properties of an ideal wire as well as the properties of a wire with weak or strong scattering are analyzed in a perturbative renormalization group calculation. This allows to recover the three regimes predicted from the divergence criteria of the response functions.
Two-time-scale population evolution on a singular landscape
NASA Astrophysics Data System (ADS)
Xu, Song; Jiao, Shuyun; Jiang, Pengyao; Ao, Ping
2014-01-01
Under the effect of strong genetic drift, it is highly probable to observe gene fixation or gene loss in a population, shown by singular peaks on a potential landscape. The genetic drift-induced noise gives rise to two-time-scale diffusion dynamics on the bipeaked landscape. We find that the logarithmically divergent (singular) peaks do not necessarily imply infinite escape times or biological fixations by iterating the Wright-Fisher model and approximating the average escape time. Our analytical results under weak mutation and weak selection extend Kramers's escape time formula to models with B (Beta) function-like equilibrium distributions and overcome constraints in previous methods. The constructed landscape provides a coherent description for the bistable system, supports the quantitative analysis of bipeaked dynamics, and generates mathematical insights for understanding the boundary behaviors of the diffusion model.
Formation of current singularity in a topologically constrained plasma.
Zhou, Yao; Huang, Yi-Min; Qin, Hong; Bhattacharjee, A
2016-02-01
Recently a variational integrator for ideal magnetohydrodynamics in Lagrangian labeling has been developed. Its built-in frozen-in equation makes it optimal for studying current sheet formation. We use this scheme to study the Hahm-Kulsrud-Taylor problem, which considers the response of a 2D plasma magnetized by a sheared field under sinusoidal boundary forcing. We obtain an equilibrium solution that preserves the magnetic topology of the initial field exactly, with a fluid mapping that is non-differentiable. Unlike previous studies that examine the current density output, we identify a singular current sheet from the fluid mapping. These results are benchmarked with a constrained Grad-Shafranov solver. The same signature of current singularity can be found in other cases with more complex magnetic topologies. PMID:26986430
Multiple unfoldings of orbifold singularities: Engineering geometric analogies to unification
Bourjaily, Jacob L.
2009-02-15
Katz and Vafa [Nucl. Phys. B497, 146 (1997)] showed how charged matter can arise geometrically by the deformation of ADE-type orbifold singularities in type IIa, M-theory, and F-theory compactifications. In this paper we use those same basic ingredients, used there to geometrically engineer specific matter representations, here to deform the compactification manifold itself in a way which naturally compliments many features of unified model building. We realize this idea explicitly by deforming a manifold engineered to give rise to an SU{sub 5} grand unified model into a one giving rise to the standard model. In this framework, the relative local positions of the singularities giving rise to standard model fields are specified in terms of the values of a small number of complex structure moduli which deform the original manifold, greatly reducing the arbitrariness of their relative positions.
A Constrained Multibody System Dynamics Avoiding Kinematic Singularities
NASA Astrophysics Data System (ADS)
Huang, Chih-Fang; Yan, Chang-Dau; Jeng, Shyr-Long; Cheing, Wei-Hua
In the analysis of constrained multibody systems, the constraint reaction forces are normally expressed in terms of the constraint equations and a vector of Lagrange multipliers. Because it fails to incorporate conservation of momentum, the Lagrange multiplier method is deficient when the constraint Jacobian matrix is singular. This paper presents an improved dynamic formulation for the constrained multibody system. In our formulation, the kinematic constraints are still formulated in terms of the joint constraint reaction forces and moments; however, the formulations are based on a second-order Taylor expansion so as to incorporate the rigid body velocities. Conservation of momentum is included explicitly in this method; hence the problems caused by kinematic singularities can be avoided. In addition, the dynamic formulation is general and applicable to most dynamic analyses. Finally the 3-leg Stewart platform is used for the example of analysis.
Formation of current singularity in a topologically constrained plasma
NASA Astrophysics Data System (ADS)
Zhou, Yao; Huang, Yi-Min; Qin, Hong; Bhattacharjee, A.
2016-02-01
Recently a variational integrator for ideal magnetohydrodynamics in Lagrangian labeling has been developed. Its built-in frozen-in equation makes it optimal for studying current sheet formation. We use this scheme to study the Hahm-Kulsrud-Taylor problem, which considers the response of a 2D plasma magnetized by a sheared field under sinusoidal boundary forcing. We obtain an equilibrium solution that preserves the magnetic topology of the initial field exactly, with a fluid mapping that is non-differentiable. Unlike previous studies that examine the current density output, we identify a singular current sheet from the fluid mapping. These results are benchmarked with a constrained Grad-Shafranov solver. The same signature of current singularity can be found in other cases with more complex magnetic topologies.
Potentially singular solutions of the 3D axisymmetric Euler equations.
Luo, Guo; Hou, Thomas Y
2014-09-01
The question of finite-time blowup of the 3D incompressible Euler equations is numerically investigated in a periodic cylinder with solid boundaries. Using rotational symmetry, the equations are discretized in the (2D) meridian plane on an adaptive (moving) mesh and is integrated in time with adaptively chosen time steps. The vorticity is observed to develop a ring-singularity on the solid boundary with a growth proportional to ∼(ts - t)(-2.46), where ts ∼ 0.0035056 is the estimated singularity time. A local analysis also suggests the existence of a self-similar blowup. The simulations stop at τ(2) = 0.003505 at which time the vorticity amplifies by more than (3 × 10(8))-fold and the maximum mesh resolution exceeds (3 × 10(12))(2). The vorticity vector is observed to maintain four significant digits throughout the computations.
A Schwarz alternating procedure for singular perturbation problems
Garbey, M.; Kaper, H.G.
1994-12-31
The authors show that the Schwarz alternating procedure offers a good algorithm for the numerical solution of singular perturbation problems, provided the domain decomposition is properly designed to resolve the boundary and transition layers. They give sharp estimates for the optimal position of the domain boundaries and present convergence rates of the algorithm for various second-order singular perturbation problems. The splitting of the operator is domain-dependent, and the iterative solution of each subproblem is based on a modified asymptotic expansion of the operator. They show that this asymptotic-induced method leads to a family of efficient massively parallel algorithms and report on implementation results for a turning-point problem and a combustion problem.