ASi Tallink Grupp aktsiate esmane avalik pakkumine
2005-01-01
21. novembril algas AS-i Tallink Grupp aktsiate esmane pakkumine Tallinna börsil: jaeinvestoritel Eestis ja Soomes ning kutselistel investoritel Eestis, Soomes ja mujal on võimalus märkida kuni 34 090 909 firma lihtaktsiat. Vt.samas: Veel üks uus laev; Tallink Grupp asutas Lätis tütarettevõtte; ASi Tallink kommentaar ajalehes "Helsingin Sanomat" 13. novembril ilmunud artiklile; "Romantika" töötab jäähoki MMil flotellina; ASi Tallink Grupp 2004/2005. majandusaasta tulemustest; "Galaxy" ristimis- ja vettelaskmistseremoonia; 2. detsembril avalikustas AS Tallink Grupp oma aktsiate esmase avaliku pakkumise lõpliku pakkumishinna ning jaotamise tulemused
Tallink City eskiis valmib sügiseks
2006-01-01
Septembris 2006 jõuab Tallinna linnavalitsuse ette Lasnamäele plaanitava lõbustuskeskuse Tallink City detailplaneeringu eskiis. Laevandusfirmas Tallink Grupp suurosalust omav Infortar plaanib 2010. aastaks rajada enam kui 160000 m2 suuruse linnaku (mäesuusahall, suusatunnel) Punasele tänavale
Tallink City eskiis valmib sügiseks
2006-01-01
Septembris 2006 jõuab Tallinna linnavalitsuse ette Lasnamäele plaanitava lõbustuskeskuse Tallink City detailplaneeringu eskiis. Laevandusfirmas Tallink Grupp suurosalust omav Infortar plaanib 2010. aastaks rajada enam kui 160000 m2 suuruse linnaku (mäesuusahall, suusatunnel) Punasele tänavale
Tallink City arendus venib / Ralf-Martin Soe
Soe, Ralf-Martin
2008-01-01
Ligi 5 miljardit krooni maksva Tallink City arendus seisab ametnike sõnul juba pool aastat. Vt. samas: Linn polnud nõus teid välja ehitama; Arendus kui poliitilise kasu allikas. Kommenteerib Indrek Toome
Tallink tõmbab kulud kokku / Kadri Bank, Silvia Kruusmaa
Bank, Kadri
2008-01-01
Suurenenud kütusekulude ja kaubavedude langusest tingitud kahjumi tõttu on Tallink Grupp sunnitud minema rangele kokkuhoiurežiimile. Kommenteerib Sten Pisang. Vt. samas Hansabank Marketsi kommentaari
Tallink City arendus venib / Ralf-Martin Soe
Soe, Ralf-Martin
2008-01-01
Ligi 5 miljardit krooni maksva Tallink City arendus seisab ametnike sõnul juba pool aastat. Vt. samas: Linn polnud nõus teid välja ehitama; Arendus kui poliitilise kasu allikas. Kommenteerib Indrek Toome
Track guided self-driven container wagon
Hansen, I.A.
1999-01-01
The linear motor consists of a series of stator coils (2) located along the Track guided self-driven container wagon Track guided self-driven container wagon track and a reaction rail (3) fitted under the wagon chassis (4).
Land, Kadri
2008-01-01
Tallink Silja AB juht vastab küsimustele, miks Tallink ei huvitu Sillamäe-Kotka või Saaremaa laevaliinist, mille poolest erineb Tallinki juhtimismeetod vana Silja omast, mida on eestlastel rootslastele õpetada, kas meie turismisektor suudab Eestit rootslastele ahvatlevaks muuta, miks Tallink Silja pole veel avanud Stockholm-Peterburi liini. Diagramm: Tallink Grupp
Land, Kadri
2008-01-01
Tallink Silja AB juht vastab küsimustele, miks Tallink ei huvitu Sillamäe-Kotka või Saaremaa laevaliinist, mille poolest erineb Tallinki juhtimismeetod vana Silja omast, mida on eestlastel rootslastele õpetada, kas meie turismisektor suudab Eestit rootslastele ahvatlevaks muuta, miks Tallink Silja pole veel avanud Stockholm-Peterburi liini. Diagramm: Tallink Grupp
Tallink on võtnud sihikule Helsingi börsi / Annika Matson
Matson, Annika, 1976-
2003-01-01
Tallink Grupi aktsiakapitali laiendamisel ettevõtte uueks aktsionäriks saanud Citigroup seadis Tallinkile nõude börsilemineku kohta aastaks 2006. Seega plaanib Tallink noteerida oma aktsiad Helsingi börsil. Diagramm: Tallinki käive ja kasum 1997-2003
Tallink on konkurentidele korraldanud tõsise tulevärgi / Raigo Neudorf
Neudorf, Raigo
2004-01-01
Tallink Grupi tegevusvaldkondadest, laienemisest ning tulevikuplaanidest. Laevakompaniide vahelisest konkurentsist Läänemerel. Tabel: Laevafirmade finantsandmed. Diagramm: Tallinki omanikering. Vt. samas: Silja Line hakkab samuti Peterburi sõitma
Tallink on konkurentidele korraldanud tõsise tulevärgi / Raigo Neudorf
Neudorf, Raigo
2004-01-01
Tallink Grupi tegevusvaldkondadest, laienemisest ning tulevikuplaanidest. Laevakompaniide vahelisest konkurentsist Läänemerel. Tabel: Laevafirmade finantsandmed. Diagramm: Tallinki omanikering. Vt. samas: Silja Line hakkab samuti Peterburi sõitma
Tallink прокладывает курс = Tallink bears the course
2004-01-01
Ülevaade Tallink Grupp AS-i laevadest ja laevaliinidest, laevaliikluse avamisest liinil Helsingi-Tallinn-Peterburi, Eesti ning Vene Föderatsiooni vaheliste koostöölepingute sõlmimisest rahvusvahelise meretranspordi valdkonnas, Euroopa Liidu laienemise mõjudest liikmesriikide merelaevandusele
Tallink прокладывает курс = Tallink bears the course
2004-01-01
Ülevaade Tallink Grupp AS-i laevadest ja laevaliinidest, laevaliikluse avamisest liinil Helsingi-Tallinn-Peterburi, Eesti ning Vene Föderatsiooni vaheliste koostöölepingute sõlmimisest rahvusvahelise meretranspordi valdkonnas, Euroopa Liidu laienemise mõjudest liikmesriikide merelaevandusele
Circle the Wagons: The History of US Army Convoy Security
2005-01-01
heavier than the steel plating, and that the weight of both quickly wore out the suspension on the trucks. Also, the bags kicked up dust caused by...the enemy would drive by and shoot at drivers from scooters . At other times they would pull in front of the last vehicle in the convoy, separate it...the war’s fi rst few years. Unfortunately though, the extra weight stressed out the suspension system and the vehicle tended to roll over on turns at
Tallink kaalub müüki pandud Silja Line'i ostu / Priit Rajalo
Rajalo, Priit, 1975-
2005-01-01
Soome Silja Oy AB omanikfirma Sea Containers otsustas 2. novembril Silja Line'i müüki panna, kuna laevafirma kasumlikkus on järsult vähenenud. Tallink Grupi finantsdirektori Janek Stalmeistri sõnul on Tallinki võimalikku ostuhuvi Silja Line'i vastu vara veel kommenteerida. Lisa: Silja laevad
Tallink kaalub müüki pandud Silja Line'i ostu / Priit Rajalo
Rajalo, Priit, 1975-
2005-01-01
Soome Silja Oy AB omanikfirma Sea Containers otsustas 2. novembril Silja Line'i müüki panna, kuna laevafirma kasumlikkus on järsult vähenenud. Tallink Grupi finantsdirektori Janek Stalmeistri sõnul on Tallinki võimalikku ostuhuvi Silja Line'i vastu vara veel kommenteerida. Lisa: Silja laevad
Tallink's profits drop while owners top the rich list / Matt Withers
Withers, Matt
2008-01-01
Laevafirma Tallink teenis 318 miljonit krooni kasumit, kuid ettevõtte käive on vähenenud. Halvad majandustulemused on tingitud finantskriisist, kütusehindade tõusust ja uue piletite broneerimissüsteemi kasutuselevõtust
Tallink's profits drop while owners top the rich list / Matt Withers
Withers, Matt
2008-01-01
Laevafirma Tallink teenis 318 miljonit krooni kasumit, kuid ettevõtte käive on vähenenud. Halvad majandustulemused on tingitud finantskriisist, kütusehindade tõusust ja uue piletite broneerimissüsteemi kasutuselevõtust
Verification Test of the Change-of-Pace Station Wagon.
1980-07-01
Cleveland, Ohio, by Electric Vehicles Associates. It is a converted AMC Pacer station wagon. It is powered by 20 6-volt batteries that are connected to... Electric Station Wagon is an electrified version of an AMC Pacer wagon, converted by Electric Vehicle Associates, Inc., 9100 Bank St., Cleveland, OH...of Electric and Hybrid Vehicles isa. OECLASSIFICATION/DOWNGRADING SCHEDULE IS. DISTRIBUTION STATEMENT (of thil Report) Approved for public release
Tallink jättis eilsel börsipäeval väikeaktsionärid infosulgu / Annika Matson
Matson, Annika, 1976-
2006-01-01
Tallink ei andnud erinevalt Viking Line'ist oma väikeaktsionäridele teada, kas osaleb Silja Line'i ostupakkumisel. Kommenteerib Raul Malmstein. Vt. samas: Lauri Matsulevitsh. Citigroup soovitab Tallinki aktsiat osta
Testing and analysis of a modernized freight wagon's elements flammability
Płaczek, M.; Wróbel, A.; Baier, A.
2016-08-01
Paper concerns an issue of freight wagon modernization using composite materials. The goal of the project is to elongate the period between repairs (by better corrosion protection) and improve conditions of exploitation of modernized freight wagons (for example easier unloading during winter conditions - no freezes of the charge to the freight wagon body shell). Application of the composite panels to the freight wagon's body shell was proposed as the solution that can solve mentioned problems. The composite panels composed of fiberglass and epoxy resin were proposed. They will be mounted on the body shell using rivet nuts. What is more the body shell of the modernized freight wagon will be painted using an anti-corrosion agent. In this paper the analysis of a flammability of the proposed composition (the composite plate made of fiberglass and epoxy resin mounted to the steel sheet with additional anticorrosion agent) is presented. In the paper results of laboratory tests conducted according to international standards are presented. A series of samples of elements of modernized freight wagons was tested using the created laboratory stand. Obtained results were averaged and the proposed material was assigned to the one of the class of materials for their combustibility.
Calculation-experimental method justifies the life of wagons
Directory of Open Access Journals (Sweden)
Валерія Сергіївна Воропай
2015-11-01
Full Text Available The article proposed a method to evaluate the technical state of tank wagons operating in chemical industry. An algorithm for evaluation the technical state of tank wagons was developed, that makes it possible on the basis of diagnosis and analysis of current condition to justify a further period of operation. The complex of works on testing the tanks and mathematical models for calculations of the design strength and reliability were proposed. The article is devoted to solving the problem of effective exploitation of the working fleet of tank wagons. Opportunities for further exploitation of cars, the complex of works on the assessment of their technical state and the calculation of the resources have been proposed in the article. Engineering research of the chemical industries park has reduced the shortage of the rolling stock for transportation of ammonia. The analysis of the chassis numerous faults and the main elements of tank wagons supporting structure after 20 years of exploitation was made. The algorithm of determining the residual life of the specialized tank wagons operating in an industrial plant has been proposed. The procedure for resource conservation of tank wagons carrying cargo under high pressure was first proposed. The improved procedure for identifying residual life proposed in the article has both theoretical and practical importance
National Research Council Canada - National Science Library
Liu, Bin
2012-01-01
... has to match the time limitation of wagon operations on marshalling stations and the wagon flow direction and train-size limitation. Besides, the train work plan has to meet the demand of wagon loading pl...
A concept of technology for freight wagons modernization
Pɫaczek, M.; Wróbel, A.; Buchacz, A.
2016-11-01
Rail transport is a very important part of the modern economy, one of the components determining its dynamic development. It is therefore important to conduct research and taking action aimed at the development and refinement of this branch of industry. Such actions directly translate into an increase in its effectiveness, safety, reduction of burden on the environment and society. Nowadays numerous studies are conducted, aimed at introducing new technologies and solutions, both in terms of railway infrastructure and logistics management systems, as well as in traction vehicles themselves. Introduction of modern technology helps eliminate or reduce nuisance problems associated with the implementation of any kind of transport or the operation of the used technical means. Presented paper concerns an issue of freight wagon modernization using composite materials. It presents a part of a research project that aim is to develop a technology of freight wagons modernization during their periodic repair. The main problem during exploitation of concerned types of freight wagons designed for coal transport is corrosion of the wagon's body shell. The goal of the project is to elongate the period between periodic repairs (by better corrosion protection) and improve conditions of exploitation of modernized freight wagons (for example easier unloading during winter conditions - no freezes of the charge to the freight wagon body shell). One of elements of the project is also to develop a system for diagnosing the technical condition of the modernized shell of wagon body during operation. For this purpose the use of non-destructive testing methods of technical state of constructions will be used, including methods that use the analysis of dynamic response of the object. Application of the composite panels to the freight wagon's body shell was proposed as the solution that can solve mentioned problems during exploitation of freight wagons. The composite panels composed of
Assessment of railway wagon suspension characteristics
Soukup, Josef; Skočilas, Jan; Skočilasová, Blanka
2017-05-01
The article deals with assessment of railway wagon suspension characteristics. The essential characteristics of a suspension are represented by the stiffness constants of the equivalent springs and the eigen frequencies of the oscillating movements in reference to the main central inertia axes of a vehicle. The premise of the experimental determination of these characteristic is the knowledge of the gravity center position and the knowledge of the main central inertia moments of the vehicle frame. The vehicle frame performs the general spatial movement when the vehicle moves. An analysis of the frame movement generally arises from Euler's equations which are commonly used for the description of the spherical movement. This solution is difficult and it can be simplified by applying the specific assumptions. The eigen frequencies solutions and solutions of the suspension stiffness are presented in the article. The solutions are applied on the railway and road vehicles with the simplifying conditions. A new method which assessed the characteristics is described in the article.
Baseline and Verification Tests of the Electric Vehicle Associates’ Current Fare Station Wagon.
1983-01-01
the EVA Current Fare Wagon. The EVA Current Fare Wagon is a 1980 Ford Fairmont station wagon which has been converted to an electric vehicle . The...standard Ford Fairmont station wagon which has been converted to an electric vehicle (Figures 1 anil 2). It is powered I% 22 6-V lead-acid batteries2...D-R132 549 BASELINE AND VERIFICATION TESTS OF THE ELECTRIC VEHICLE 112 ASSOCIATES’ CURRE..(U) ARMY MOBILITY EQUIPMENT RESEARCH AIND DEVELOPMENT
Traffic Noise Propagating from Vibration of Railway Wagon
Directory of Open Access Journals (Sweden)
Shao-Yi Hsia
2013-01-01
Full Text Available Traffic noise has become a serious environmental hazard as more cars are purchased and driven. To help objectively and subjectively reduce perceived noise load, methods to analyze traffic noise offer an important means of creating a design to reduce noise output from main sources and transmission routes. Acoustic analysis using BEASY and dynamic analysis using ANSYS are conducted to forecast noise at a distance of 15 m from a railway wagon travelling at 100 km/h. This noise is based on structural vibration only and it excludes other noise sources from the railway wagon. The simulation results demonstrate that the overall noise at 15 m from a railway wagon car is 85.1 dB(L from linear energy weighting calculation and 72.9 dB(A from the A-weighting calculation. In this study, noise level propagating from vibration of the railway wagon is measured or calculated using A-weighting filter to simulate the frequency response of the human ear. The study results can be useful to factories, companies, or organizations and can provide an important resource and help reduce traffic noise. This can be achieved by predetermining the test location and structure configuration and adapting local planning and thus preventing excessive traffic noise in residential areas.
Physical and electrocardiographic evaluation of horses used for wagon traction
Directory of Open Access Journals (Sweden)
M.M. Bomfim
Full Text Available ABSTRACT The objective of this research was to evaluate the electrocardiogram (ECG of horses used for wagon traction and to compare the results with the parameters obtained from inactive horses or horses submitted to a training routine. Fifty-six 3-15-year-old healthy horses (22 females and 34 males were divided into three groups: control (without a work routine; N=21, wagon traction (N=25 and athlete (N=10 and submitted to physical examination and ECG (at rest. The rhythm, heart rate (HR, amplitude and duration of ECG waveforms and intervals were obtained from the frontal plane and base-apex leads. Heart score (HS was calculated using the arithmetic mean of QRS duration in LI, LII and LIII. Measurements of ECG waves were smaller in control group, in comparison with wagon traction and athlete groups, suggesting that exercise can change ECG. Similar results were observed in the wagon traction and athlete groups, but the electrophysiological adjustments to exercise were not the same for these groups.
Solving Problems through Circles
Grahamslaw, Laura; Henson, Lisa H.
2015-01-01
Several problem-solving interventions that utilise a "circle" approach have been applied within the field of educational psychology, for example, Circle Time, Circle of Friends, Sharing Circles, Circle of Adults and Solution Circles. This research explored two interventions, Solution Circles and Circle of Adults, and used thematic…
Solving Problems through Circles
Grahamslaw, Laura; Henson, Lisa H.
2015-01-01
Several problem-solving interventions that utilise a "circle" approach have been applied within the field of educational psychology, for example, Circle Time, Circle of Friends, Sharing Circles, Circle of Adults and Solution Circles. This research explored two interventions, Solution Circles and Circle of Adults, and used thematic…
DEFF Research Database (Denmark)
Nordentoft, Helle Merete; Thomsen, Rie; Möller, Jonas
in career guidance development. In the paper we draw on the preliminary findings from an ongoing Nordic project: “The future of career guidance and educational counselling”. Specifically, we explore the career guidance practitioners´ response to research circles as means to professional development. We......It is key challenge to continuously develop guidance practices to meet participants´ needs and demands from policy makers. The European Lifelong Guidance Policy Network (ELGPN) states that the guidance practitioner and citizens/users should be the focus of development of international and national...... lifelong guidance policies. This paper presents `research circles´ as a way to develop guidance practices through long-term research relationships between practice and research. Research circles support a bottom up approach to policy development just like ELGPN considers to be necessary and required...
Katz, Claudia Anne; Kuby, Sue Ann
2002-01-01
Describes the use of literature circles, a student-led reading and discussion method that encourages students to see stories in various ways. Explains the student selection of titles, roles of group members, and collaborative projects that complete the activity. (LRW)
Płaczek, M.; Wróbel, A.; Buchacz, A.
2016-08-01
Paper presents an analysis of the possibility of application of piezoelectric foils - Macro Fiber Composite (MFC) in modernized freight wagons. It was verified if they can be successfully applied as sensors in developed system for structural health monitoring and in energy harvesting system. It is a part of a research project that aim is to develop a technology of freight wagons modernization. The goal of the project is to elongate the period between periodic repairs (by better corrosion protection) and improve conditions of exploitation of modernized wagons (easier unloading during winter conditions - no freezes of the charge to the freight wagon body shell). The additional aim is to develop system for structural health monitoring of the modernized body of the freight wagon as well as the system supporting management of a fleet of wagons using GPS system with power supply based on the energy recovered by MFC's from the wagon's vibrations during its exploitation. Results of laboratory tests as well as results of measurements on the real freight wagon during observed driving of the wagon are presented. At the same time measurements of the electric voltage generated by the MFC transducers excited by low frequencies harmonic excitation were verified.
DEFF Research Database (Denmark)
Ling, Richard; Bjelland, Johannes; Sundsøy, Pål
2014-01-01
This article examines how we use mobile telephony to maintain our physically and socially closest social circle. The analysis is based on traffic data gathered from Norway using approximately 24 million calls and texts made by private individuals. Previous research has shown that our temporal and...... as information and communication technologies (ICTs) potentially put the world at our fingertips, the mobile phone is an instrument of a more limited geographical and social sphere. Approximately two-thirds of our calls/texts go to strong ties that are within a 25-km radius.......This article examines how we use mobile telephony to maintain our physically and socially closest social circle. The analysis is based on traffic data gathered from Norway using approximately 24 million calls and texts made by private individuals. Previous research has shown that our temporal...
The Dynamics of a Railway Freight Wagon Wheelset with dry friction Damping
DEFF Research Database (Denmark)
True, Hans; Asmund, Rolf
2002-01-01
We investigate the dynamics of a simple model of a wheelset that supports one end of a railway freight wagon by springs with linear characteristics and dry friction dampers. The wagon runs on an ideal, straight and level track with constant speed. The lateral dynamics in dependence on the speed...
Vision system for measuring wagon buffers’ lateral movements
Directory of Open Access Journals (Sweden)
Barjaktarović Marko
2013-01-01
Full Text Available This paper presents a vision system designed for measuring horizontal and vertical displacements of a railway wagon body. The model comprises a commercial webcam and a cooperative target of an appropriate shape. The lateral buffer movement is determined by calculating target displacement in real time by processing the camera image in a LabVIEW platform using free OpenCV library. Laboratory experiments demonstrate an accuracy which is better than ±0.5 mm within a 50 mm measuring range.
Increasing the Efficiency of Railway Transport by Improvement of Suspension of Freight Wagons
Directory of Open Access Journals (Sweden)
Dragan Petrović
2012-11-01
Full Text Available Railway transport has a very important role in economy of every country. The efficiency of railway transport depends both on the quality of transport organization and on the technical reliability of the railway rolling stock. During operation of the railway freight wagons in the last years, a large number of breaks of suspension system elements have been noticed. This feature is especially reported at four-axle double wagon for coal transport (designated Fbd and three-axle wagon for transport of cars (designated DDam. Frequent breaks of suspension system elements reduce the efficiency of transport and in some cases cause derailment of wagons and lead to large economic losses. In this paper, the causes of breakage of suspension on both wagons (Fbd and DDam have been analyzed, but also the possibilities of how to resolve these problems, i.e. how to reduce them to a minimum or avoid them completely.
The continuous Wagon Wheel Illusion is object-based.
VanRullen, Rufin
2006-11-01
The occurrence of perceived reversed motion while observers view a periodic, continuously moving stimulus (the "continuous Wagon Wheel Illusion") has been taken as evidence that some aspects of motion perception rely on discrete sampling of visual information. The spatial extent of this sampling is currently under debate. When two separate motion stimuli are viewed simultaneously, the illusion of reversed motion rarely occurs for both objects together: this rules out global sampling of the visual field. The same result holds when the objects are superimposed by transparency: this argues against location-based sampling. Here we show that the sampling is in fact object-based: we use a rotating ring stimulus split in two halves. When the two halves move in opposite directions, appearing to belong to separate objects, perceptual reversals occur in either half at a time, but rarely in both. When the two halves physically move in compatible directions, they generally appear to reverse simultaneously: the illusion keeps the perceptual object united. Rather than the local low-level properties of the motion stimulus (which are comparable in both cases), it is thus the high-level organization of the scene that determines the extent of perceived motion reversals. These results imply that the continuous Wagon Wheel Illusion, and any discrete perceptual sampling that may cause it, is restricted to the object of our attention.
The dynamics of European two-axle railway freight wagons with UIC standard suspension
DEFF Research Database (Denmark)
Hoffmann, Mark; True, Hans
2008-01-01
The dynamics of two-axle railway freight wagons with the UIC standard Suspension is investigated theoretically and the dynamic behaviour is explained. Fully nonlinear models are considered. The hysteresis from dry friction and the effect of impacts between elements of the suspension are included....... Different wheel-rail geometries are investigated and the results commented. Bifurcation diagrams ale used to describe the eigen-dynamics of the wagons....
Model of the UIC link suspension for freight wagons
Energy Technology Data Exchange (ETDEWEB)
Piotrowski, J. [Warsaw Univ. of Technology, Inst. of Vehicles, ul. Narbutta Warszawa (Poland)
2003-12-01
The paper presents a model of the UIC link suspension for freight wagons with emphasis on its longitudinal and lateral characteristics, which influence the lateral dynamics of the vehicle. The functioning of the suspension in the horizontal plane is realised by a number of technical (pivoted) pendulums composing linkages. The main feature of the joints of linkages is internal rolling/sliding in the presence of dry friction. The dissipation of energy by dry friction in the joints is the only source of damping, which influences the lateral dynamics of the vehicle. After detailed modelling of the technical pendulum, phenomenological models of the suspension are built, which reproduce the characteristics of the suspension using simple elements. A three-parameter model with one dry-friction slider and two linear springs reproduces the lateral characteristic of the suspension. A nine-parameter model with four dry-friction sliders and five springs reproduces the longitudinal characteristic. The models, using a method of non-smooth mechanics, may be directly implemented to vehicle/track dynamic simulations. (orig.)
Efficient circle detection by midpoint circle validation
Institute of Scientific and Technical Information of China (English)
ZHANG Shuai; CAO Junjie; LIU Xiuping
2012-01-01
Circular objects detection in digital images, a vital and recurring problem in image processing and computer vision, has many applications especially aiding vectorization of line drawing images, pupil and iris detection, circular traffic sign detection, and so on. In this paper, we lever Midpoint Circle Algorithm to speed up circle validation with sub-pixel precision. At the same time, we combine the least square method to improve the accuracy of circle detection. Experimental results from tests on synthetic and natural images validate that the proposed technique is efficiency regarding accuracy, speed and robustness.
Study on the Organization Model of Wagon Flows in Railway Terminal
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
Railway terminal is an important part of railway network. Transport organization of railway terminal is the key of the railway transport organization. Moreover, the organization of transport work is based on the organization of wagon flows in the railway terminal. Because of the great amounts of equipment and a large number of train operations, the study on railway terminal transport organization is mostly focused on a marshalling station in railway terminal or a part of it. Systematic study taking railway terminal as a whole is very few. In this paper, the organization of wagon flows in a railway terminal is analyzed and a wagon flow model in a railway terminal is established. The main principles of organization of local trains are also presented.
Directory of Open Access Journals (Sweden)
Xing-cai Liu
2014-01-01
Full Text Available The railway freight center stations location and wagon flow organization in railway transport are interconnected, and each of them is complicated in a large-scale rail network. In this paper, a two-stage method is proposed to optimize railway freight center stations location and wagon flow organization together. The location model is present with the objective to minimize the operation cost and fixed construction cost. Then, the second model of wagon flow organization is proposed to decide the optimal train service between different freight center stations. The location of the stations is the output of the first model. A heuristic algorithm that combined tabu search (TS with adaptive clonal selection algorithm (ACSA is proposed to solve those two models. The numerical results show the proposed solution method is effective.
Institute of Scientific and Technical Information of China (English)
amS
2012-01-01
实用性超强的微型车北斗星就是国产的第一代Wagon R．最近第五代已在日本问世。和之前的几代车型一样，铃木公司在推出第五代Wagon R的同时也发布了它的Stingray高性能版。新车在外观和内饰两方面都进行了修整，而并没有进行大的改变。
Directory of Open Access Journals (Sweden)
Gaurab Bhowmick
2013-10-01
Full Text Available EMU or the Electric Multiple Units are those type of trains consisting of self-propelled carriages using electricity as the motive power. An EMU requires no separate locomotives, as electric traction motors are incorporated within one or a number of carriages. Generally EMUs are used for passenger train but the same technology can be implemented in freight carriages also. These EMU based freight cars will reduce the line congestion mainly in India due to its rapid acceleration and high speeds.In this study, the purpose of the carriage is to be self-propelled using highly efficient traction motors powering each carriage made of high strength Aluminum having individual and independent wheel set. Also, the wagon will harness the waste braking energy using regenerative braking technique to power the traction motors partially. This study addresses the problem of severe line congestion, unwanted holding of freight trains to make passageway for passenger trains, light weight wagons, harnessing the wastage braking energy which are generally removed as heat. Therefore, study of the methodologies suggested has to be done in order to determine the feasibility and effectiveness of the methods both in terms of technology and financially. To achieve this detailed analysis is carried out to understand the modification of normal freight wagon to self-propelled EMU type wagon.
Dynamics of two-axle railway freight wagons with UIC standard suspension
DEFF Research Database (Denmark)
Hoffmann, Mark; True, Hans
2006-01-01
The dynamics of two different two-axle railway freight wagons is investigated theoretically and compared. Fully nonlinear models are considered. The hysteresis from dry friction and the effect of impacts between elements of the suspension are included. Bifurcation diagrams are shown in order...
Fatigue test of a fiberglass based composite panel. Increasing the lifetime of freight wagon
Sobek, M.; Baier, A.; Grabowski, Ł.; Majzner, M.
2016-08-01
In the XXI century transportation of goods plays a key role in the economy. Due to a good logistics the economy is able to grow fluently. Although land transportation is carried out mainly through trucks for the last several years there has been noted an increase in the percentage share of rail transport in the freight transport. The main goods transported by railways are mineral fuels, mining and quarrying products. They constitute the greater part of 70% of total transported goods. Transportation of material of such high weight, high hardness and with different shapes involves increased and accelerated wear and tear of the cargo space of the wagon. This process is also magnified by substances used to prevent overheating or goods theft. Usually they are in the form of chemical compounds powder, eg. Calcium. A very large impact on the wear of the freight wagons hull is made because of mechanical damage. Their source comes mostly from loading cargo with impetus and using heavy machines during unloading. A large number of cycles of loading and unloading during the working period causes abrasion of body and as a result after several years a wagon car qualifies for a major maintenance. Possibility of application composite panels in the process of renovating the wagons body could reduce the weight of whole train and prolong the service life between mandatory technical inspection. The Paper "Fatigue test of a fiberglass based composite panel. Increasing the lifetime of freight wagon" presents the research process and the results of the endurance test of the composite panel samples fixed to a metal plate. As a fixing method a stainless steel rivet nut and a stainless steel button head socket screws were chosen. Cyclic and multiple load were applied to test samples using a pneumatic cylinder. Such a methodology simulated the forces resulting from loading and unloading of the wagon and movement of the cargo during transport. In the study a dedicated stand equipped with a
Fruchard, Augustin
2010-01-01
A circle C holds a convex body K if C does not meet the interior of K and if there does not exist any euclidean displacement which moves C as far as desired from K, avoiding the interior of K. The purpose of this note is to explore how small can be a holding circle.
US Fish and Wildlife Service, Department of the Interior — This document is a contract agreement for building a horse stable and a wagon house at the Leadville National Fish Hatchery during its original construction.
Groups of Circle Diffeomorphisms
Navas, Andrés
2011-01-01
In recent years scholars from a variety of branches of mathematics have made several significant developments in the theory of group actions. Groups of Circle Diffeomorphisms systematically explores group actions on the simplest closed manifold, the circle. As the group of circle diffeomorphisms is an important subject in modern mathematics, this book will be of interest to those doing research in group theory, dynamical systems, low dimensional geometry and topology, and foliation theory. The book is mostly self-contained and also includes numerous complementary exercises, making it an excell
Bin Liu
2012-01-01
The wagon flow scheduling plays a very important role in transportation activities in railway bureau. However, it is difficult to implement in the actual decision-making process of wagon flow scheduling that compiled under certain environment, because of the interferences of uncertain information, such as train arrival time, train classify time, train assemble time, and flexible train-size limitation. Based on existing research results, considering the stochasticity of all kinds of train oper...
Remembering Tomorrow: Wagon Roads, Identity and the Decolonization of a First Nations Landscape
Directory of Open Access Journals (Sweden)
Erin L.S. Gibson
2016-12-01
Full Text Available Roads embody the experiences of those who construct, use and maintain them through time. Using a biographical approach I explore how memory and identity are entangled in the material remains of a wagon road in southwestern British Columbia, Canada. First constructed by the Royal Engineers in 1859 to enable miners to reach the Fraser River goldfields, the importance of this road transcends its colonial origins. Entwined in different webs of meaning, the material remains of the wagon road continue to play a role in the lives of people today. In this article I investigate the significance of this wagon road to the indigenous Stl’atl’imx (pronounced Stat-lee-um people of the lower Lillooet River Valley who aim to preserve it as a part of decolonizing and reclaiming their traditional territory and identity. I also look at the road’s importance to a group of Grade 10 students who experience it as part of a high school excursion that teaches outdoor survival skills alongside lessons about British Columbia’s historic past. While these two groups have different experiences of the colonial encounter, for each their understanding of the road goes beyond its physical form to its ‘place’ in understanding their own identity.
Domain Discretization and Circle Packings
DEFF Research Database (Denmark)
Dias, Kealey
A circle packing is a configuration of circles which are tangent with one another in a prescribed pattern determined by a combinatorial triangulation, where the configuration fills a planar domain or a two-dimensional surface. The vertices in the triangulation correspond to centers of circles......, and edges correspond to two circles (having centers corresponding to the endpoints of the edge) being tangent to each other. This circle packing creates a rigid structure having an underlying geometric triangulation, where the centers of circles again correspond to vertices in the triangulation......, and the edges are geodesic segments (Euclidean, hyperbolic, or spherical) connecting centers of circles that are tangent to each other. Three circles that are mutually tangent form a face of the triangulation. Since circle packing is closely related to triangulation, circle packing methods can be applied...
Clausen-May, Tandi
2006-01-01
In this article, the author describes two Powerpoint presentations designed to help visual learners calculate the circumference and the area of a circle. In particular, the author describes how these presentations can be used to establish mental images that can help pupils to understand, and so recall, the principles that underlie the formulae for…
Shelton-Strong, Scott J.
2012-01-01
While the intrinsic value of reading extensively for L2 learners has rarely been questioned, practicalities of implementation and the existence of gains beyond lexical enrichment have generated discussion. This article outlines and explores the benefits which Literature Circles (LCs) offer to English language learning and attempts to identify…
General minisum circle location
DEFF Research Database (Denmark)
Körner, Mark; Brimberg, Jack; Juel, Henrik
2009-01-01
In our paper we approximate a set of given points by a general circle. More precisely, we consider the problem of locating and scaling the unit ball of some given norm k1 with respect to xed points on the plane such that the sum of weighted distances between the circle and the xed points is minim......In our paper we approximate a set of given points by a general circle. More precisely, we consider the problem of locating and scaling the unit ball of some given norm k1 with respect to xed points on the plane such that the sum of weighted distances between the circle and the xed points...... is minimized, where the distance is measured by a norm k2. We present results for the general case. In the case that k1 and k2 are both block norms, we are able to identify a nite dominating set in R3 for the problem, which can be obtained as the intersection of cones....
Differentiating through Literature Circles
Helgeson, John
2017-01-01
This article begins with an example of a typical middle-school experience with literature circles. Students read a common text and come prepared to share and discuss the text based on individual roles they are assigned. Teachers are using this practice to address the complexity levels of texts in order to help students develop the skills they need…
Quantum Cosmology in Bergmann-Wagoner Scalar-tensor Gravitational Theory
Pimentel, L O; Pimentel, Luis O.; Mora, Cesar
2000-01-01
The Wheeler-DeWitt equation is solved for the Bergmann-Wagoner scalar-tensor gravitational theory in the case of Friedmann-Robertson- Walker cosmological model. We present solutions for several cosmological functions: i) \\lambda(\\phi)=0, ii) \\lambda(\\phi)=3\\Lambda_0\\phi and iii) a more complex \\lambda(\\phi), that depends on the choice of the coupling function, considering closed, flat and hyperbolic Friedmann universes (k=1, 0, -1). In the first two cases we show particular quantum wormhole solutions. Also, classical solutions are considered for some scalar-tensor theories, and we study the third quantization of some minisuperspace models.
Energy Technology Data Exchange (ETDEWEB)
Dowgiallo, E.J. Jr.; Chapman, R.D.
1983-01-01
The EVA Current Fare Wagon was manufactured by Electric Vehicle Associates, Incorporated (EVA) of Cleveland, Ohio. It is now available from Lectra Motors Corp. of Las Vegas, Nevada. The vehicle was tested under the direction of MERADCOM from 27 March 1980 to 6 November 1981. The tests are part of a Department of Energy project to assess advances in electric vehicle design. This report presents the performance test results on the EVA Current Fare Wagon. The EVA Current Fare Wagon is a 1980 Ford Fairmont station wagon which has been converted to an electric vehicle. The propulsion system is made up of a Cableform controller, a series-wound 30-hp Reliance Electric Motor, and 22 6-V lead-acid batteries. The Current Fare Wagon is also equipped with regenerative braking. Further details of the vehicle are given in the Vehicle Summary Data Sheet, Appendix A. The results of this testing are given in Table 1.
Directory of Open Access Journals (Sweden)
David Dennis
2005-01-01
Full Text Available Given a bounded sequence of integers {d0,d1,d2,…}, 6≤dn≤M, there is an associated abstract triangulation created by building up layers of vertices so that vertices on the nth layer have degree dn. This triangulation can be realized via a circle packing which fills either the Euclidean or the hyperbolic plane. We give necessary and sufficient conditions to determine the type of the packing given the defining sequence {dn}.
DEFF Research Database (Denmark)
Ejsing-Duun, Stine
2011-01-01
This chapter analyses the relationship between players, the game world, and the ordinary world in alternative reality games (ARGs) and location-based games (LBGs). These games use technology to create a game world in the everyday scene. The topic of this chapter is the concept of the 'magic circle......', which defines the relationship between play and the ordinary world, and how this concept relates to a new kind of game....
DEFF Research Database (Denmark)
Ejsing-Duun, Stine
2011-01-01
This chapter analyses the relationship between players, the game world, and the ordinary world in alternative reality games (ARGs) and location-based games (LBGs). These games use technology to create a game world in the everyday scene. The topic of this chapter is the concept of the 'magic circle......', which defines the relationship between play and the ordinary world, and how this concept relates to a new kind of game....
Gericke, C.; Hecht, M.
2012-05-01
Despite the fact that rail freight transport is one of the most environmentally friendly matters of transport, its growth has been far behind the growth of freight transport in general. Studies showed that a competitive disadvantage is caused by a low availability of rolling stock, especially freight wagons. Changing from a time based to a condition based maintenance strategy is believed to decrease down times by at least one third. To make condition based maintenance for freight wagons possible the TU Berlin and five industry partners started the research project CargoCBM. One task in this project is to develop algorithms for the automatic on-board diagnosis of wheel flats. The focus of the work is on the process of feature generation and feature selection as well as the application of different classifiers to automatically evaluate the data. Based on the results of measured data, features were selected and tested with different classifiers. Thought advanced classifiers such as neural networks have been analysed in accordance to their classification accuracy. It can be shown that with carefully constructed and selected features comparatively simple classifiers can lead to excellent results.
Wong, Chin Hong; Dahari, Zuraini; Jumali, Mohammad Hafizuddin; Mohamed, Khairudin; Mohamed, Julie Juliewatty
2017-03-01
Harvesting vibrational energy from impacting raindrops using piezoelectric material has been proven to be a promising approach for future outdoor applications, providing a good alternative resource that can be applied in outdoor rainy environments. We present herein an optimum novel polyvinylidene fluoride (PVDF) piezoelectric transducer specifically developed to harvest raindrop energy. The finite-element method was applied for simulation and optimization of the piezoelectric raindrop energy harvester (PREH) using COMSOL Multiphysics software, investigating the electrical potential, surface charge density, and total displacement for different transducer dimensions. According to the simulation results, the structure that generated the highest electrical potential and surface charge density was a wagon-wheel-shaped structure consisting of six spokes with wheel diameter of 30 mm, spoke width of 2 mm, center pad diameter of 6 mm, and thickness of 25 μm. This optimum wagon-wheel-shaped device was then fabricated by spin coating of PVDF, sputtering of aluminum, a poling process, and computer numerical control machining of a polytetrafluoroethylene stand. The fabricated PREH was characterized by x-ray diffraction analysis and Fourier-transform infrared spectroscopy. Finally, the fabricated PREH was tested under actual rain conditions with an alternating current to direct current converter connected in parallel, revealing that a single cell could generate average peak voltage of 22.5 mV and produce electrical energy of 3.4 nJ from ten impacts in 20 s.
Wong, Chin Hong; Dahari, Zuraini; Jumali, Mohammad Hafizuddin; Mohamed, Khairudin; Mohamed, Julie Juliewatty
2017-01-01
Harvesting vibrational energy from impacting raindrops using piezoelectric material has been proven to be a promising approach for future outdoor applications, providing a good alternative resource that can be applied in outdoor rainy environments. We present herein an optimum novel polyvinylidene fluoride (PVDF) piezoelectric transducer specifically developed to harvest raindrop energy. The finite-element method was applied for simulation and optimization of the piezoelectric raindrop energy harvester (PREH) using COMSOL Multiphysics software, investigating the electrical potential, surface charge density, and total displacement for different transducer dimensions. According to the simulation results, the structure that generated the highest electrical potential and surface charge density was a wagon-wheel-shaped structure consisting of six spokes with wheel diameter of 30 mm, spoke width of 2 mm, center pad diameter of 6 mm, and thickness of 25 μm. This optimum wagon-wheel-shaped device was then fabricated by spin coating of PVDF, sputtering of aluminum, a poling process, and computer numerical control machining of a polytetrafluoroethylene stand. The fabricated PREH was characterized by x-ray diffraction analysis and Fourier-transform infrared spectroscopy. Finally, the fabricated PREH was tested under actual rain conditions with an alternating current to direct current converter connected in parallel, revealing that a single cell could generate average peak voltage of 22.5 mV and produce electrical energy of 3.4 nJ from ten impacts in 20 s.
Directory of Open Access Journals (Sweden)
Bin Liu
2012-01-01
Full Text Available The wagon flow scheduling plays a very important role in transportation activities in railway bureau. However, it is difficult to implement in the actual decision-making process of wagon flow scheduling that compiled under certain environment, because of the interferences of uncertain information, such as train arrival time, train classify time, train assemble time, and flexible train-size limitation. Based on existing research results, considering the stochasticity of all kinds of train operation time and fuzziness of train-size limitation of the departure train, aimed at maximizing the satisfaction of departure train-size limitation and minimizing the wagon residence time at railway station, a stochastic chance-constrained fuzzy multiobjective model for flexible wagon flow scheduling problem is established in this paper. Moreover, a hybrid intelligent algorithm based on ant colony optimization (ACO and genetic algorithm (GA is also provided to solve this model. Finally, the rationality and effectiveness of the model and algorithm are verified through a numerical example, and the results prove that the accuracy of the train work plan could be improved by the model and algorithm; consequently, it has a good robustness and operability.
DEFF Research Database (Denmark)
Jaeger, Thomas Arvid
2012-01-01
a common professional language like in mathematics, colour and music. The result is a weaker professionalism in the aesthetic competences compared to the professionalism and competences in other areas. A research project [1] on contrasts or opposites in form investigated the phenomenon in the fields...... by this model, and using the knowledge gathered from the other areas, especially perception psychology, it showed to be a possible way to organize contrasts in form, a system of 4 different opposites, geometric, organic, mass and structure: The Circle of Form....
Directory of Open Access Journals (Sweden)
Gianluca Olcese
2009-01-01
Full Text Available Myths, symbols and rituals of carnival survive from ancient times, preserving their affinities among different cultures: Carnival is strictly connected with agricultural life: each of its manifestations is provided to propitiate growth and health. As nature follows a circle through the rhythm of the seasons, carnival expresses the circularity of the process of birth, death and regeneration. The psychological and anthropological analysis and both historical and geographical comparison of its different aspects, permits to explain the process that led carnival to its actual reality.
van Gijn, Jan; Gijselhart, Joost P
2012-01-01
Thomas Willis (1621-1675) grew up in Wiltshire and studied medicine in Oxford, at a time when the city was besieged and then occupied by Parliamentarian troops. He started his career as a country doctor while concurrently taking part in informal gatherings with other scientists (William Petty, Christopher Wren and, later on, Robert Hooke, Richard Lower and Robert Boyle). They performed physical and chemical experiments and carried out a variety of tests on animals. After the restoration of the monarchy in 1660 Willis combined his practice with academic teaching. From then on he focused his studies on the structure and function of the brain, dissecting brains after removal from the skull and fixation in 'spirit of wine'. In his 'Cerebri anatome' of 1664, illustrated by Wren, he drew attention to the arterial circle at the base of the brain, including its physiological advantages. This arterial circle had been incompletely described by others in the past and fully, but only in writing, by Wepfer in 1658.
Ruggles, Clive L. N.
During the 1970s and early 1980s, British archaeoastronomers were striving to bridge the interpretative gulf between the "megalithic observatories" of Alexander Thom and an archaeological mainstream that, generally speaking, was hostile to any mention of astronomy in relation to the megalithic monuments of Neolithic and Early Bronze Age Britain. The Scottish recumbent stone circles (RSCs) came to represent an example where sounder methodology could overcome many of the data selection issues that had beset earlier studies and, with due restraint, produce credible interpretations. Systematic studies of their orientations consistently concluded that the RSCs had a strong lunar connection, and it was widely envisaged that they were the setting for ceremonies associated with the appearance of the moon over the recumbent stone. Other evidence such as the presence of white quartz and the spatial distribution of cupmarks appeared to back up this conclusion. New archaeological investigations since 1999 have challenged and modified these conclusions, confirming in particular that the circles were built to enclose cairns rather than to demarcate open spaces. Yet the restricted pattern of orientations of these structures could only have been achieved by reference to the basic diurnal motions of the skies, and orientation in relation to simple observations of the midsummer moon remains the most likely reading of the alignment evidence taken as a whole. On the other hand, a consideration of the broader context, which includes the nearby Clava cairns, highlights instead the symbolic importance of the sun.
Colomo, F
2007-01-01
The problem of limit shapes in the six-vertex model with domain wall boundary conditions is addressed by considering a specially tailored bulk correlation function, the emptiness formation probability. A closed expression of this correlation function is given, both in terms of certain determinant and multiple integral, which allows for a systematic treatment of the limit shapes of the model for full range of values of vertex weights. Specifically, we show that for vertex weights corresponding to the free-fermion line on the phase diagram, the emptiness formation probability is related to a one-matrix model with a triple logarithmic singularity, or Triple Penner model. The saddle-point analysis of this model leads to the Arctic Circle Theorem, and its generalization to the Arctic Ellipses, known previously from domino tilings.
A Less Conservative Circle Criterion
2008-01-01
A weak form of the Circle Criterion for Lur'e systems is stated. The result allows prove global boundedness of all system solutions. Moreover such a result can be employed to enlarge the set of nonlinearities for which the standard Circle Criterion can guarantee absolute stability.
Testing of Composite Panels Used as Components of a Freight Wagon by Thermovision
Directory of Open Access Journals (Sweden)
Wróbel Andrzej
2016-03-01
Full Text Available In this paper research methods for detection of laminate panels damage were presented. The most common damage is: matrix cracking laminate interlayer damage to joints, connecting cracks, delamination and fiber breakage. The tested laminates will be used as assemblies and sub-assemblies of freight wagon. Other methods of modeling of machines by means of transducers are shown in Płaczek (2012, 2015 and Białas (2010. As part of the project authors were collaborated with specialists from other research centers and scientific research (Bocian and Kulisiewicz, 2013. As a part of future work the places where we will be able to replace the standard materials by parts made of laminate will be shown. Layered composites despite many advantages have also disadvantages. From last mentioned it is a relatively low resistance to transverse impact. When the laminate is used as a decorative element, its small damage is not a problem. The problems start when the composite satisfies more responsible tasks such as: is a part of the technical means for example of a railway wagon. Aspect of continuous monitoring of the technical state of the laminate is very important. Current technology provides numerous opportunities for non-destructive methods of technical inspections. In this paper method for testing of large areas, completely non-contact, based on the methods of thermography, was presented. It consists heating by using the composite tubes and examining it through a thermal imaging camera. Length of heating, and consequently the temperature to which the laminate is heated mostly were chosen experimentally. During the measurements, the camera measures the intensity of radiation, not temperature. Received thermogram is not always a precise representation of the actual temperature, because the camera does not reach only the radiation from tested object, but also reaches the radiation coming from the environment and reflected objects etc. As part of the research
Partial covering of a circle by equal circles. Part II: The case of 5 circles
Directory of Open Access Journals (Sweden)
Zsolt Gáspár
2014-05-01
Full Text Available How must n equal circles of given radius r be placed so that they cover as great a part of the area of the unit circle as possible? In this Part II of a two-part paper, a conjectured solution of this problem for n = 5 is given for r varying from the maximum packing radius to the minimum covering radius. Results are obtained by applying a mechanical model described in Part I. A generalized tensegrity structure is associated with a maximum area configuration of the 5 circles, and by using catastrophe theory, it is pointed out that the ''equilibrium paths'' have bifurcations, that is, at certain values of r, the type of the tensegrity structure and so the type of the circle configuration changes.
Locating a minisum circle in the plane
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Schöbel, Anita
2009-01-01
We consider the problem of locating a circle with respect to existing facilities in the plane such that the sum of weighted distances between the circle and the facilities is minimized, i.e., we approximate a set of given points by a circle regarding the sum of weighted distances. If the radius...... of the circle is a variable we show that there always exists an optimal circle passing through two of the existing facilities. For the case of a fixed radius we provide characterizations of optimal circles in special cases. Solution procedures are suggested....
The Voronoi diagram of circles made easy
DEFF Research Database (Denmark)
Anton, François; Mioc, Darka; Gold, Christopher
2007-01-01
Proximity queries among circles could be effectively answered if the Delaunay graph for sets of circles could be computed in an efficient and exact way. In this paper, we first show a necessary and sufficient condition of connectivity of the Voronoi diagram of circles. Then, we show how the Delau......Proximity queries among circles could be effectively answered if the Delaunay graph for sets of circles could be computed in an efficient and exact way. In this paper, we first show a necessary and sufficient condition of connectivity of the Voronoi diagram of circles. Then, we show how...
Feeman, Timothy G.
2011-01-01
We generalize a standard example from precalculus and calculus texts to give a simple description in polar coordinates of any circle that passes through the origin. We discuss an occurrence of this formula in the context of medical imaging. (Contains 1 figure.)
The Circle Approach to Trigonometry
Moore, Kevin c.; LaForest, Kevin R.
2014-01-01
How do students think about an angle measure of ninety degrees? How do they think about ratios and values on the unit circle? How might angle measure be used to connect right-triangle trigonometry and circular functions? And why might asking these questions be important when introducing trigonometric functions to students? When teaching…
Topological conjugacy of circle diffeomorphisms
1995-01-01
The classical criterion for a circle diffeomorphism to be topologically conjugate to an irrational rigid rotation was given by A. Denjoy. In 1985, one of us (Sullivan) gave a new criterion. There is an example satisfying Denjoy's bounded variation condition rather than Sullivan's Zygmund condition and vice versa. This paper will give the third criterion which is implied by either of the above criteria.
Feeman, Timothy G.
2011-01-01
We generalize a standard example from precalculus and calculus texts to give a simple description in polar coordinates of any circle that passes through the origin. We discuss an occurrence of this formula in the context of medical imaging. (Contains 1 figure.)
Energy Technology Data Exchange (ETDEWEB)
Dowgiallo, E.J. Jr; Chapman, R.D.
1983-01-01
The EVA Current Fare Station Wagon, an electric vehicle, was tested at MERADCOM as part of a Department of Energy project to characterize the state-of-the-art of electric vehicles. The current Fare Wagon was manufactured in Cleveland, Ohio by Electric Vehicle Associates' Incorporated. It is powered by 22 6-V lead-acid batteries driving a 30-hp d.c. series motor through an SCR controller. The motor drives the rear wheels through a manually operated 4-speed transmission. Regenerative braking was provided.
NUMERICAL SIMULATION ANALYSIS OF EXTERNAL FLOW FIELD OF WAGON-SHAPED CAR AT THE MOMENT OF PASSING
Institute of Scientific and Technical Information of China (English)
GU Zhengqi; HE Yibin; ZHOU Wei; JIANG Bo
2008-01-01
In the course of studying on aerodynamic change and its effect on steering stability and controllability of an automobile in passing, because of multi interaction streams, it is difficult to use traditional methods, such as wind tunnel test and road test. If the passing process of an automobile is divided into many time segments, so as to avoid the use of moving mesh which takes large calculation resource and CPU processing time in calculating, the segments are simulated with computational fluid dynamics (CFD) method, then the approximate computational results about external flow field will be obtained. On the basis of the idea, the change of external flow field of wagon-shaped car at the moment of passing is simulated through solving three-dimensional, steady and uncompressible N-S equations with finite volume method. Numerical simulation analysis of side force coefficient, stream lines, body surface pressure distribution of wagon-shaped car are presented and a preliminary discussion of aerodynamic characteristics of correlative situations is obtained. Finally, the Cs -x/l curve of side force coefficient(Cs) of car following relative distance (x/l) between cars is obtained. By comparison, the curve is coincident well with the experimental data,which shows creditability of numerical simulation methods presented.Key words: External flow field Passing Numerical simulation Side force coefficient
Yarning Circles in the Literacy Classroom
Mills, Kathy A.; Sunderland, Naomi; Davis-Warra, John
2014-01-01
This article explains how the speaking and listening practice of yarning circles can be used in the literacy classroom. The article opens with an account of a live enactment of yarning circles with elementary students in a mainstream classroom in Australia. It explains the purpose and origin of yarning circles in Indigenous communities, and…
Science Literacy Circles: Big Ideas about Science
Devick-Fry, Jane; LeSage, Teresa
2010-01-01
Science literacy circles incorporate the organization of both science notebooks and literature circles to help K-8 students internalize big ideas about science. Using science literacy circles gives students opportunities to engage in critical thinking as they inductively develop understanding about science concepts. (Contains 1 table and 7…
Cosmic crystallography in a circle
Teixeira, A F F
2000-01-01
In a circle (an $S^1$) with circumference 1 assume $m$ objects distributed pseudo-randomly. In the universal covering $R^1$ assume the objects replicated accordingly, and take an interval $L>1$. In this interval, make the normalized histogram of the pair separations which are not an integer. The theoretical (expected) such histogram is obtained in this report, as well as its difference to a similar histogram for non-replicated objects. The whole study is of interest for the cosmic crystallography.
Nanogrid rolling circle DNA sequencing
Energy Technology Data Exchange (ETDEWEB)
Church, George M.; Porreca, Gregory J.; Shendure, Jay; Rosenbaum, Abraham Meir
2017-04-18
The present invention relates to methods for sequencing a polynucleotide immobilized on an array having a plurality of specific regions each having a defined diameter size, including synthesizing a concatemer of a polynucleotide by rolling circle amplification, wherein the concatemer has a cross-sectional diameter greater than the diameter of a specific region, immobilizing the concatemer to the specific region to make an immobilized concatemer, and sequencing the immobilized concatemer.
On a conjecture concerning helly circle graphs
Directory of Open Access Journals (Sweden)
Durán Guillermo
2003-01-01
Full Text Available We say that G is an e-circle graph if there is a bijection between its vertices and straight lines on the cartesian plane such that two vertices are adjacent in G if and only if the corresponding lines intersect inside the circle of radius one. This definition suggests a method for deciding whether a given graph G is an e-circle graph, by constructing a convenient system S of equations and inequations which represents the structure of G, in such a way that G is an e-circle graph if and only if S has a solution. In fact, e-circle graphs are exactly the circle graphs (intersection graphs of chords in a circle, and thus this method provides an analytic way for recognizing circle graphs. A graph G is a Helly circle graph if G is a circle graph and there exists a model of G by chords such that every three pairwise intersecting chords intersect at the same point. A conjecture by Durán (2000 states that G is a Helly circle graph if and only if G is a circle graph and contains no induced diamonds (a diamond is a graph formed by four vertices and five edges. Many unsuccessful efforts - mainly based on combinatorial and geometrical approaches - have been done in order to validate this conjecture. In this work, we utilize the ideas behind the definition of e-circle graphs and restate this conjecture in terms of an equivalence between two systems of equations and inequations, providing a new, analytic tool to deal with it.
The Southern Ocean CIRCLE initiative
Murphy, E. J.; Ellis-Evans, J. C.
2003-04-01
The circumpolar Southern Ocean is the principal ocean connection between the Atlantic, Pacific and Indian Oceans, and exerts a profound influence on world climate through ocean circulation and its major role in the global carbon cycle. It is a major repository of biodiversity and also the only ocean system where significant marine living resources are yet to be fully exploited. However, this key component of the Earth System is still poorly understood, in part due to the logistical problems of a harsh, remote location and the circumpolar nature of the environment. Circumpolar patterns of variability have now been recognized and the current challenge is to understand how, at a circumpolar scale, this variability is generated, its impact on the regional biogeochemical cycles, its interaction with ecosystem processes and the links to global scale processes. Many of these scientific issues can only be addressed by Southern Ocean scale studies, and although a range of national and international research programmes are already targeting particular aspects, the research effort is largely uncoordinated. The European Polar Board is sponsoring a pan-European initiative (Southern Ocean CIRCLE) to coordinate the currently disparate Southern Ocean research effort and this initiative aims to address climate variability, biogeochemical cycling and ecosystem dynamics with particular reference to the links between these aspects in the circumpolar Southern Ocean. This poster outlines the development of the SO CIRCLE initiative, the major areas of science and proposals for implementation. It also outlines how SO CIRCLE will link to other programmes with a Southern Ocean component (e.g. CLIVAR, CliC, GLOBEC, SOLAS). A key aspect of the initiative will be to coordinate European scientific effort in the Southern Ocean with that of the wider international community.
Chadzitaskos, G; Tolar, J
2011-01-01
We present a possible construction of coherent states on the unit circle as configuration space. In our approach the phase space is the product Z x S^1. Because of the duality of canonical coordinates and momenta, i.e. the angular variable and the integers, this formulation can also be interpreted as coherent states over an infinite periodic chain. For the construction we use the analogy with our quantization over a finite periodic chain where the phase space was Z_M x Z_M. Properties of the coherent states constructed in this way are studied and the coherent states are shown to satisfy the resolution of unity.
Hopf, J. F.; Lindenmeier, H. K.; Reiter, L. M.
2003-04-01
For modern cars, antennas are required for AM reception, FM and TV diversity reception, weatherband reception (USA), terrestrial digital radio, remote control functions, keyless entry, mobile phone for all worldwide used systems, GPS, and in the future, satellite broadcast radio services. Those services cover the frequency range from 150 kHz up to 2.4 GHz. Such kind of a multiantenna system developed for station wagons is presented in this paper. The obtainable FM and TV diversity effectiveness is discussed for several types of antenna arrangements in detail. This value is the number of fictitious completely decorrelated antenna signals and is obtained by virtual test drives. The characteristic of the respective antennas under test is introduced in the software as antenna pattern, measured or calculated with respect to amplitude and phase. During the computer analysis the car with the antennas is driven virtually through a Rayleigh field scenario with desired and undesired signals.
Fairy circle landscapes under the sea
Ruiz-Reynés, Daniel
2017-08-03
Short-scale interactions yield large-scale vegetation patterns that, in turn, shape ecosystem function across landscapes. Fairy circles, which are circular patches bare of vegetation within otherwise continuous landscapes, are characteristic features of semiarid grasslands. We report the occurrence of submarine fairy circle seascapes in seagrass meadows and propose a simple model that reproduces the diversity of seascapes observed in these ecosystems as emerging from plant interactions within the meadow. These seascapes include two extreme cases, a continuous meadow and a bare landscape, along with intermediate states that range from the occurrence of persistent but isolated fairy circles, or solitons, to seascapes with multiple fairy circles, banded vegetation, and
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Schöbel, Anita
2007-01-01
We consider the problem of locating a spherical circle with respect to existing facilities on a sphere, such that the sum of distances between the circle and the facilities is minimized or such that the maximum distance is minimized. The problem properties are analyzed, and we give solution...... procedures. When the circle to be located is restricted to be a great circle, some simplifications are possible. The models may be used in preliminary studies on the location of large linear facilities on the earth's surface, such as superhighways, pipelines, and transmission lines, or in totally different...
Euclidean Circles and Their Modular Images.
Austin, Joe Dan
1990-01-01
Shows a series of Euclidean equations using the Euclidean algorithm to get the greatest common divisor of two integers. Describes the use of the equations to generate a series of circles. Discusses computer generation of Euclidean circles and provides a BASIC program. (YP)
Unit Circles and Inverse Trigonometric Functions
Barrera, Azael
2014-01-01
Historical accounts of trigonometry refer to the works of many Indian and Arab astronomers on the origin of the trigonometric functions as we know them now, in particular Abu al-Wafa (ca. 980 CE), who determined and named all known trigonometric functions from segments constructed on a regular circle and later on a unit circle (Moussa 2011;…
Meromorphic Vector Fields and Circle Packings
DEFF Research Database (Denmark)
Dias, Kealey
to structurally stable vector fields, there is an underlying dynamically defined triangulation of the plane. Circle packings are a means to realize such a given combinatorial structure. About 20 years ago, W. Thurston suggested applying circle packings to obtain approximations to Riemann mappings. This gave rise...
Building Background Knowledge within Literature Circles
Barone, Diane; Barone, Rebecca
2012-01-01
The authors examined the strength of literature circles in developing background knowledge--an acknowledged sticking point in the development of understanding for middle graders--with a special focus on the literature circle role of "investigator," where it is student initiative and not teacher direction that guides comprehension. Observing…
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Schöbel, Anita
2003-01-01
We consider the problem of locating a spherical circle with respect to existing facilities on a sphere, such that the sum of weighted distances between the circle and the facilities is minimized, or such that the maximum weighted distance is minimized. The problem properties are analyzed, and we ...
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Schöbel, Anita
2007-01-01
We consider the problem of locating a spherical circle with respect to existing facilities on a sphere, such that the sum of distances between the circle and the facilities is minimized or such that the maximum distance is minimized. The problem properties are analyzed, and we give solution proce...
军用危险货物运输对铁路车辆的需求%Requirements of Railway Wagons on Transportation of Military Dangerous Goods
Institute of Scientific and Technical Information of China (English)
程虹; 于洋; 季锋; 曾已泷
2012-01-01
To counter the main problem of the military dangerous goods railway transportation combined with the trend of our country＇ s railway technical development. This paper analyzed the characteristics of railway transportations of military dangerous goods and the requirements of railway wagons. It is helpful to provide technical support to resolve the problems of railway wagons in military dangerous goods＇ transportation.%针对当前军用危险货物铁路运输中存在的主要问题，结合我国铁路技术装备发展趋势，研究分析军用危险货物铁路运输特点及对铁路车辆的要求，为解决军用危险货物铁路运输车辆保障难题提供技术支持。
Lines, Circles, Planes and Spheres
Purdy, George B
2009-01-01
Let $S$ be a set of $n$ points in $\\mathbb{R}^3$, no three collinear and not all coplanar. If at most $n-k$ are coplanar and $n$ is sufficiently large, the total number of planes determined is at least $1 + k \\binom{n-k}{2}-\\binom{k}{2}(\\frac{n-k}{2})$. For similar conditions and sufficiently large $n$, (inspired by the work of P. D. T. A. Elliott in \\cite{Ell67}) we also show that the number of spheres determined by $n$ points is at least $1+\\binom{n-1}{3}-t_3^{orchard}(n-1)$, and this bound is best possible under its hypothesis. (By $t_3^{orchard}(n)$, we are denoting the maximum number of three-point lines attainable by a configuration of $n$ points, no four collinear, in the plane, i.e., the classic Orchard Problem.) New lower bounds are also given for both lines and circles.
Plasmid Rolling-Circle Replication.
Ruiz-Masó, J A; MachóN, C; Bordanaba-Ruiseco, L; Espinosa, M; Coll, M; Del Solar, G
2015-02-01
Plasmids are DNA entities that undergo controlled replication independent of the chromosomal DNA, a crucial step that guarantees the prevalence of the plasmid in its host. DNA replication has to cope with the incapacity of the DNA polymerases to start de novo DNA synthesis, and different replication mechanisms offer diverse solutions to this problem. Rolling-circle replication (RCR) is a mechanism adopted by certain plasmids, among other genetic elements, that represents one of the simplest initiation strategies, that is, the nicking by a replication initiator protein on one parental strand to generate the primer for leading-strand initiation and a single priming site for lagging-strand synthesis. All RCR plasmid genomes consist of a number of basic elements: leading strand initiation and control, lagging strand origin, phenotypic determinants, and mobilization, generally in that order of frequency. RCR has been mainly characterized in Gram-positive bacterial plasmids, although it has also been described in Gram-negative bacterial or archaeal plasmids. Here we aim to provide an overview of the RCR plasmids' lifestyle, with emphasis on their characteristic traits, promiscuity, stability, utility as vectors, etc. While RCR is one of the best-characterized plasmid replication mechanisms, there are still many questions left unanswered, which will be pointed out along the way in this review.
Examination of the Circle Spline Routine
Dolin, R. M.; Jaeger, D. L.
1985-01-01
The Circle Spline routine is currently being used for generating both two and three dimensional spline curves. It was developed for use in ESCHER, a mesh generating routine written to provide a computationally simple and efficient method for building meshes along curved surfaces. Circle Spline is a parametric linear blending spline. Because many computerized machining operations involve circular shapes, the Circle Spline is well suited for both the design and manufacturing processes and shows promise as an alternative to the spline methods currently supported by the Initial Graphics Specification (IGES).
Circle Detection Based on HSI Color Space
Institute of Scientific and Technical Information of China (English)
MAOXia; LIXing-xin; XUEYu-li
2005-01-01
A method based on HSI color space is presented to solve the problem of circle detection from color images. In terms of the evaluation to the edge detection method based on intensity, the edge detection based on hue is chosen to process the color image, and the simplified calculation of hue transform is discussed. Then the algorithm of circle detection based on Canny edge detection is proposed. Due to the dispersive distribution of the detected result, Hough transformation and template smooth are used in circle detection, and the proposed method gives a quite good result.
Directory of Open Access Journals (Sweden)
Rufin VanRullen
Full Text Available A continuous periodic motion stimulus can sometimes be perceived moving in the wrong direction. These illusory reversals have been taken as evidence that part of the motion perception system samples its inputs as a series of discrete snapshots -although other explanations of the phenomenon have been proposed, that rely on the spurious activation of low-level motion detectors in early visual areas. We have hypothesized that the right inferior parietal lobe ('when' pathway plays a critical role in timing perceptual events relative to one another, and thus we examined the role of the right parietal lobe in the generation of this "continuous Wagon Wheel Illusion" (c-WWI. Consistent with our hypothesis, we found that the illusion was effectively weakened following disruption of right, but not left, parietal regions by low frequency repetitive transcranial magnetic stimulation (1 Hz, 10 min. These results were independent of whether the motion stimulus was shown in the left or the right visual field. Thus, the c-WWI appears to depend on higher-order attentional mechanisms that are supported by the 'when' pathway of the right parietal lobe.
Information flow through the disaster circle
DEFF Research Database (Denmark)
Egedorf, Maren Marie; Villanueva Holm-Nielsen, Pablo
2015-01-01
not necessarily flow across the phases of the circle in an effective manner. This is particularly true for the information that crosses the disaster point of the circle. Organisations carry out assessments, surveys and baselines for various purposes, at various points of time in the disaster circle. Output......The traditional view of the disaster circle is phase based. Disaster and development professionals recognize that the actions carried out in the various phases of the disaster management cycle are overlapping and build upon each other, having resilience as the overall goal. However information does...... is communicated in long reports that are very time consuming to review. These reports often contain information that is re-gathered in emergency assessments and don’t share the original data upon which conclusions were made. The paper aims to identify information required to make informed decisions in response...
Darboux cyclides and webs from circles
Pottmann, Helmut
2012-01-01
Motivated by potential applications in architecture, we study Darboux cyclides. These algebraic surfaces of order ≤4 are a superset of Dupin cyclides and quadrics, and they carry up to six real families of circles. Revisiting the classical approach to these surfaces based on the spherical model of 3D Möbius geometry, we provide computational tools for the identification of circle families on a given cyclide and for the direct design of those. In particular, we show that certain triples of circle families may be arranged as so-called hexagonal webs, and we provide a complete classification of all possible hexagonal webs of circles on Darboux cyclides. © 2011 Elsevier B.V. All rights reserved.
Enhanced Quantization: The particle on the circle
Geloun, Joseph Ben
2012-01-01
Enhanced quantization is an improved program for overcoming difficulties which may arise during an ordinary canonical quantization procedure. We review here how this program applies for a particle on circle.
Circle Packing for Origami Design Is Hard
Demaine, Erik D; Lang, Robert J
2010-01-01
We show that deciding whether a given set of circles can be packed into a rectangle, an equilateral triangle, or a unit square are NP-hard problems, settling the complexity of these natural packing problems. On the positive side, we show that any set of circles of total area 1 can be packed into a square of size 8/pi=2.546... These results are motivated by problems arising in the context of origami design.
Experiments Testing the Causes of Namibian Fairy Circles.
Directory of Open Access Journals (Sweden)
Walter R Tschinkel
Full Text Available The grasslands on the sandy soils of the eastern edge of the Namib Desert of Namibia are strikingly punctuated by millions of mostly regularly-spaced circular bare spots 2 to 10 m or more in diameter, generally with a margin of taller grasses. The causes of these so called fairy circles are unknown, but several hypotheses have been advanced. In October 2009, we set up experiments that specifically tested four hypothesized causes, and monitored these 5 times between 2009 and 2015. Grass exclusion in circles due to seepage of subterranean vapors or gases was tested by burying an impermeable barrier beneath fairy circles, but seedling density and growth did not differ from barrier-less controls. Plant germination and growth inhibition by allelochemicals or nutrient deficiencies in fairy circle soils were tested by transferring fairy circle soil to artificially cleared circles in the grassy matrix, and matrix soil to fairy circles (along with circle to circle and matrix to matrix controls. None of the transfers changed the seedling density and growth from the control reference conditions. Limitation of plant growth due to micronutrient depletion within fairy circles was tested by supplementing circles with a micronutrient mixture, but did not result in differences in plant seedling density and growth. Short-range vegetation competitive feedbacks were tested by creating artificially-cleared circles of 2 or 4 m diameter located 2 or 6 m from a natural fairy circle. The natural circles remained bare and the artificial circles revegetated. These four experiments provided evidence that fairy circles were not caused by subterranean vapors, that fairy circle soil per se did not inhibit plant growth, and that the circles were not caused by micronutrient deficiency. There was also no evidence that vegetative feedbacks affected fairy circles on a 2 to 10 m scale. Landscape-scale vegetative self-organization is discussed as a more likely cause of fairy circles.
Experiments Testing the Causes of Namibian Fairy Circles.
Tschinkel, Walter R
2015-01-01
The grasslands on the sandy soils of the eastern edge of the Namib Desert of Namibia are strikingly punctuated by millions of mostly regularly-spaced circular bare spots 2 to 10 m or more in diameter, generally with a margin of taller grasses. The causes of these so called fairy circles are unknown, but several hypotheses have been advanced. In October 2009, we set up experiments that specifically tested four hypothesized causes, and monitored these 5 times between 2009 and 2015. Grass exclusion in circles due to seepage of subterranean vapors or gases was tested by burying an impermeable barrier beneath fairy circles, but seedling density and growth did not differ from barrier-less controls. Plant germination and growth inhibition by allelochemicals or nutrient deficiencies in fairy circle soils were tested by transferring fairy circle soil to artificially cleared circles in the grassy matrix, and matrix soil to fairy circles (along with circle to circle and matrix to matrix controls). None of the transfers changed the seedling density and growth from the control reference conditions. Limitation of plant growth due to micronutrient depletion within fairy circles was tested by supplementing circles with a micronutrient mixture, but did not result in differences in plant seedling density and growth. Short-range vegetation competitive feedbacks were tested by creating artificially-cleared circles of 2 or 4 m diameter located 2 or 6 m from a natural fairy circle. The natural circles remained bare and the artificial circles revegetated. These four experiments provided evidence that fairy circles were not caused by subterranean vapors, that fairy circle soil per se did not inhibit plant growth, and that the circles were not caused by micronutrient deficiency. There was also no evidence that vegetative feedbacks affected fairy circles on a 2 to 10 m scale. Landscape-scale vegetative self-organization is discussed as a more likely cause of fairy circles.
Expanding-Circle Students Learning "Standard English" in the Outer-Circle Asia
Kobayashi, Yoko
2011-01-01
Drawing upon Kachru's concentric circles of English, the present study explores whether middle-class Japanese students who chose to study English solo at private language schools in Singapore diverge from many others who (wish to) study inner-circle English. The study is stimulated by the repeated interdisciplinary findings that, in spite of the…
Maxi-circles and mini-circles in kinetoplast DNA from Trypanosoma cruzi.
W. Leon; A.C.C. Frasch; J.H.J. Hoeijmakers (Jan); F. Fase-Fowler; P. Borst (Piet); F. Brunel; J. Davison
1980-01-01
textabstractMaxi-circles are a minor component of kinetoplast DNAs from all trypanosomatids studied, but they have not previously been found in Trypanosoma cruzi; We have spread intact kinetoplast DNA from the epimastigotes of strain Y in protein monolayers and analysed the mini-circle networks by e
Packing circles and spheres on surfaces
Schiftner, Alexander
2009-12-01
Inspired by freeform designs in architecture which involve circles and spheres, we introduce a new kind of triangle mesh whose faces\\' incircles form a packing. As it turns out, such meshes have a rich geometry and allow us to cover surfaces with circle patterns, sphere packings, approximate circle packings, hexagonal meshes which carry a torsion-free support structure, hybrid tri-hex meshes, and others. We show how triangle meshes can be optimized so as to have the incircle packing property. We explain their relation to conformal geometry and implications on solvability of optimization. The examples we give confirm that this kind of meshes is a rich source of geometric structures relevant to architectural geometry.
ENTREPRENEURSHIP EDUCATION AND THE ECONOMY VICIOUS CIRCLES
Directory of Open Access Journals (Sweden)
MEDAR LUCIAN ION
2015-06-01
Full Text Available Education for sustainable development, involves training honest, active, social and creative persons for ensuring the link between environment, society, economy and politics. Trained entrepreneurs in sustainable development, are the engine system which can bring an economic prosperity. Lack of entrepreneurial education in the last 25 years has led accentuated conditions to avoiding economic development in all reference fields where added value can be achieved. Running away from excessive taxation led to the establishment of vicious circles in the economy. Vicious circles of the economy can be found in saving, tax policy, productive investment and the informal economy. Through this study will present the importance of entrepreneurship education in the real economy and some specifications to exit entrepreneurs from vicious circles of the economy.
Synchronisation in Coupled Sine Circle Maps
Chatterjee, N; Chatterjee, Nandini; Gupte, Neelima
1995-01-01
We study the spatially synchronized and temporally periodic solutions of a 1-d lattice of coupled sine circle maps. We carry out an analytic stability analysis of this spatially synchronized and temporally periodic case and obtain the stability matrix in a neat block diagonal form. We find spatially synchronized behaviour over a substantial range of parameter space. We have also extended the analysis to higher spatial periods with similar results. Numerical simulations for various temporal periods of the synchronized solution, reveal that the entire structure of the Arnold tongues and the devil's staircase seen in the case of the single circle map can also be observed for the synchronized coupled sine circle map lattice. Our formalism should be useful in the study of spatially periodic behaviour in other coupled map lattices.
Packing circles and spheres on surfaces
Schiftner, Alexander
2009-01-01
Inspired by freeform designs in architecture which involve circles and spheres, we introduce a new kind of triangle mesh whose faces\\' incircles form a packing. As it turns out, such meshes have a rich geometry and allow us to cover surfaces with circle patterns, sphere packings, approximate circle packings, hexagonal meshes which carry a torsion-free support structure, hybrid tri-hex meshes, and others. We show how triangle meshes can be optimized so as to have the incircle packing property. We explain their relation to conformal geometry and implications on solvability of optimization. The examples we give confirm that this kind of meshes is a rich source of geometric structures relevant to architectural geometry. © 2009 ACM.
Study Circles and Socio-cultural Animation
Directory of Open Access Journals (Sweden)
Vilma Malečkar
2001-12-01
Full Text Available Informal learning and participating in study circles is a way of applying the ideas of socio-cultural animation. It is based on the assumption that within a society there are mechanisms that institutions don't comprise and therefore don't fulfil various, often urgent needs deriving from everyday life and the community. What is going on here is identifying and solving burning problems; some of them have already become an integral part of the way of living in a community. Study circles as an informal phenomenon in Slovenia create new possibilities of social activities based on common learning and participating in a community.
Institute of Scientific and Technical Information of China (English)
郭垂江; 雷定猷
2014-01-01
Reasonable scheduling for placing-in and taking-out wagons in railway siding is of great significance to improve the operation efficiency of shunting locomotive and speeding up wagon’s turn-round. Under given conditions, taking the locomotive running time between sites as weights, the paper transforms the problem of placing-in (or taking-out) wagons into the shortest route problem of Hamilton graph and changed as assignment problem. The Hungarian algorithm is applied to calculate the optimal solution of the assignment problem. Then the lower bound or optimal solution of shortest route is obtained. If it is not a optimal solution, the broken-circle and connection method designed will be applied to find the satisfactory order of placing-in and taking-out wagons, and its computation complexity is O(n2). The paper simultaneously makes a deep discussion on other forms, such as placing-in and transferring combined, taking-out and transferring combined, placing-in and taking-out combined, placing-in-transferring and taking-out combined. Finally, an example is given to illustrate the model’s formulation and solution process. A large number of small cases also show that the algorithm’s average complexity and performance is relative superior.%合理安排铁路专用线取送车顺序，对提高调车机车作业效率、加速货车周转具有重要的意义。在已知条件下，以机车在装卸点间走行时间为权，把树枝形专用线取（送）车作业优化问题转换成哈密尔顿图最短路问题，并松弛为指派问题，采用匈牙利算法求出指派问题的最优解，可得到最短回路路长的下界或最优解。若未得到最优解，再利用破圈连接法求出满意的取（送）车顺序，此算法的复杂度为O(n2)。同时对送兼调移、取兼调移、取送结合、送调取结合作业形式进行了深入地讨论。最后举例说明了模型的构造及求解过程。大量小规模案例表明
Partial covering of a circle by equal circles. Part I: The mechanical models
Directory of Open Access Journals (Sweden)
Zsolt Gáspár
2014-05-01
Full Text Available How must n equal circles of given radius be placed so that they cover as great a part of the area of the unit circle as possible? To analyse this mathematical problem, mechanical models are introduced. A generalized tensegrity structure is associated with a maximum area configuration of the n circles, whose equilibrium configuration is determined numerically with the method of dynamic relaxation, and the stability of equilibrium is investigated by means of the stiffness matrix of the tensegrity structure. In this Part I, the principles of the models are presented, while an application will be shown in the forthcoming Part II.
Study of Cleaning Process for Railway Tank Wagon in Petrochemicsl Plants%石化企业自备铁路罐车清洗工艺
Institute of Scientific and Technical Information of China (English)
杨建庭; 翟延光
2016-01-01
结合某企业自备铁路罐车洗罐站的技术改造升级，分析了原洗罐工艺存在的问题，比较了铁路罐车普洗及其它几种特洗工艺的优点和缺点，进行了以带压水作为介质进行罐车清洗工艺的应用试验，根据该工艺的实际应用效果，提出了进一步改进的建议。%The problem of cleaning process for railway tank wagon in petrochemical plants was analyzed .The uncomplicated cleaning and meticulous rinsing processes about railway tank wagon in petrochemical plants were introduced .Adaptability ,economic benefits and general sanitation for each meticulous rinsing process were discussed .The cleaning test based on water with pres‐sure was made .The improvement suggestion on the cleaning process was given .
AN ITERATIVE EQUATION ON THE UNIT CIRCLE
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
A functional equation of nonlinear iterates is discussed on the circle S1 for its continuous solutions and differentiable solutions. By lifting to R, the existence, uniqueness and stability of those solutions are obtained. Techniques of continuation are used to guarantee the preservation of continuity and differentiability in lifting.
Quantization of Presymplectic Manifolds and Circle Actions
Silva, A C; Tolman, S; Silva, Ana Canas da; Karshon, Yael; Tolman, Susan
1997-01-01
We prove several versions of "quantization commutes with reduction" for circle actions on manifolds that are not symplectic. Instead, these manifolds possess a weaker structure, such as a spin^c structure. Our theorems work whenever the quantization data and the reduction data are compatible; this condition always holds if we start from a presymplectic (in particular, symplectic) manifold.
Raccoon Circles: A Handbook for Facilitators.
Cain, Jim
This handbook presents a collection of over 35 experiential and adventure-based activities using only a single item of equipment--a 15-foot long section of 1-inch tubular climbing webbing, called a raccoon circle. Some of the activities are quiet, some are loud, and they range from low to high challenge levels. Different-sized groups can be…
Syllable Circles for Pronunciation Learning and Teaching
Whipple, John; Cullen, Charlie; Gardiner, Keith; Savage, Tim
2015-01-01
Syllable Circles are interactive visualizations representing prominence as a feature in short phrases or multi-syllable words. They were designed for computer-aided pronunciation teaching. This study explores whether and how interactive visualizations can affect language learners' awareness of prominence, or stress, in English pronunciation. The…
THREE CIRCLES MODEL REVITALISASI LEMBAGA PENGELOLA ZAKAT
Directory of Open Access Journals (Sweden)
Yulinartati Yulinartati
2013-12-01
of revitalization of management of zakat, infak, and sadaqah institutions. Type of research is survey research by applying descriptive qualitative method. The results of this study found that management needs to revitalize institutions of zakat, infak, and sedekah as described in the Three Circles Model.
On circle map coupled map lattice
Ahmed, E
2002-01-01
Circle map in one and two dimensions is studied. Both its stability, synchronization using bounded control and persistence is discussed. This work is expected to be applicable in ecology where spatial effects are known to be important. Also it will be relevant to systems where delay effects are not negligible.
Mathematics Teachers Circle around Problem Solving
Fernandes, Anthony; Koehler, Jacob; Reiter, Harold
2011-01-01
Making problem solving a central part of teaching may be challenging to teachers who have limited experiences in learning and teaching mathematics in this way. Math Teachers' Circles were developed with the aim of establishing a "culture of problem solving" among middle school mathematics teachers. This culture could then be carried back into…
Community Social Work and the Learning Circle
Lavan, Ann
2008-01-01
Outlines an approach for introducing students to Community Social Work by use of clear, engaging stated objectives. Approach is called the Learning Circle and was devised as a tool to enhance student participation and to stimulate networking, dialogue and conversation about social work commitment to community intervention and community-based…
Locating a circle on the plane using the minimax criterion
2006-01-01
We consider the problem of locating a circle with respect to existing facilities on the plane, such that the largest weighted distance between the circle and the facilities is minimized. The problem properties are analyzed, and a solution procedure proposed.
Locating a circle on the plane using the minimax criterion
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Schoebel, Anita
2006-01-01
We consider the problem of locating a circle with respect to existing facilities on the plane, such that the largest weighted distance between the circle and the facilities is minimized. The problem properties are analyzed, and a solution procedure proposed.......We consider the problem of locating a circle with respect to existing facilities on the plane, such that the largest weighted distance between the circle and the facilities is minimized. The problem properties are analyzed, and a solution procedure proposed....
The "Us" in Discuss: Grouping in Literature Circles
Batchelor, Katherine
2012-01-01
This article describes one middle school teacher's use of literature circles using heterogeneous grouping. It begins with a brief rationale for using literature circles in the language arts classroom. Next, it describes techniques to form literature circles. Then, it shares how to build and establish a supportive environment within each group. It…
Locating a general minisum 'circle' on a plane
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Körner, Mark-Christoph
2011-01-01
We approximate a set of given points in the plane by the boundary of a convex and symmetric set which is the unit circle of some norm. This generalizes previous work on the subject which considers Euclidean circles only. More precisely, we examine the problem of locating and scaling the unit circle...
Optimal State Estimation of Pure Qubits on Circles
Institute of Scientific and Technical Information of China (English)
A. Ugulava; ZHANG Li-Hua; L. Chotorlishvili; SONG Wei; V. Skrinnikov; CAO Zhuo-Liang; G. Mchedlishvili
2008-01-01
We consider the problem of state estimation of qubits chosen from circles. It is shown that any qubit encoded in pairs chosen from a fixed circle parallel to the x-y equator with different phases contains the same information. We also investigate the problem of state estimation of qubits from three circles. The optimal estimation fidelity is derived.
A Spring Playscape Project: Building a Tree Circle
Keeler, Rusty
2009-01-01
The Tree Circle is a green gathering area for children made by planting trees in a circle. For children, the Tree Circle becomes a magical place for dramatic play, quiet retreat, or lively nature exploration. For teachers and parents it becomes a shady grove for snacks and stories. The trees create a sweet spot that changes during the seasons and…
A Spring Playscape Project: Building a Tree Circle
Keeler, Rusty
2009-01-01
The Tree Circle is a green gathering area for children made by planting trees in a circle. For children, the Tree Circle becomes a magical place for dramatic play, quiet retreat, or lively nature exploration. For teachers and parents it becomes a shady grove for snacks and stories. The trees create a sweet spot that changes during the seasons and…
Carinelli, S; Kühnemund, M; Nilsson, M; Pividori, M I
2017-07-15
This work addresses the design of an Ebola diagnostic test involving a simple, rapid, specific and highly sensitive procedure based on isothermal amplification on magnetic particles with electrochemical readout. Ebola padlock probes were designed to detect a specific L-gene sequence present in the five most common Ebola species. Ebola cDNA was amplified by rolling circle amplification (RCA) on magnetic particles. Further re-amplification was performed by circle-to-circle amplification (C2CA) and the products were detected in a double-tagging approach using a biotinylated capture probe for immobilization on magnetic particles and a readout probe for electrochemical detection by square-wave voltammetry on commercial screen-printed electrodes. The electrochemical genosensor was able to detect as low as 200 ymol, corresponding to 120 cDNA molecules of L-gene Ebola virus with a limit of detection of 33 cDNA molecules. The isothermal double-amplification procedure by C2CA combined with the electrochemical readout and the magnetic actuation enables the high sensitivity, resulting in a rapid, inexpensive, robust and user-friendly sensing strategy that offers a promising approach for the primary care in low resource settings, especially in less developed countries. Copyright © 2016 Elsevier B.V. All rights reserved.
2001-01-01
The first trucks transporting material from LEP and its four experiments left CERN on 31 January. Since the LEP dismantling operation began, the material had been waiting to be removed from the sites of the four experiments and the special transit area on the Prévessin site. On the evening of 30 January, the French customs authorities gave the green light for the transport operation to begin. So first thing the next day, the two companies in charge of recycling the material, Jaeger & Bosshard (Switzerland) and Excoffier (France), set to work. Only 1500 truckloads to go before everything has been removed!
Gimenez, Suzanne L.
2012-01-01
The author's journey as a strategic staffing principal in the Charlotte-Mecklenburg Schools has been one of ups and downs, scary turns and some great success for students. It began in May 2008 when she was asked to move to Devonshire Elementary School with marching orders to "turn the school around." Because of its failure to meet annual…
Gimenez, Suzanne L.
2012-01-01
The author's journey as a strategic staffing principal in the Charlotte-Mecklenburg Schools has been one of ups and downs, scary turns and some great success for students. It began in May 2008 when she was asked to move to Devonshire Elementary School with marching orders to "turn the school around." Because of its failure to meet annual…
Robust Controller Synthesis Based on Circle Criterion
Fuwa, Katsuhiko; Kato, Hiroyuki; Kando, Hisashi
It is well-known that stability margins (gain and phase margins) are important quantitative indicators for evaluating stability in feedback control system synthesis. However, when we use conventional techniques based on such stability margins, it may be difficult to suppress the vibration from high-order modes of mechanical system. This paper proposes the robust controller synthesis which achieves both the conventional stability margins and the second phase margin which is a quantitative indicator for suppressing the vibration. The basic idea is to synthesize controller such that the Nyquist locus of open-loop transfer function encircles the immediate outer side of the circle which is specified by the conventional stability margins and the second phase margin. This is formulated as modified H∞ mixed sensitivity problem with the weighting constants which are decided by the center and radius of the circle.
Circle Points Discharge Tube Current Controller
Institute of Scientific and Technical Information of China (English)
Meng Jinjia; Meng Lisheng
2005-01-01
Circle points discharge tube current controller is a new type device to limit theoutput of high voltage discharge current. Circle points uniform corona discharge to form airionization current in the discharge tube. On the outside, even if the discharge electrode is sparkdischarging or the two discharge electrodes are short circuited, the air ionization current in the tuberemains within a stable range, and there is no spark discharge. In this case, when the dischargecurrent only increases slightly, the requirement to limited current is obtained. By installing thecontroller at a discharge pole with a small power but high voltage supply, we can realize the shiftbetween the continuous spark line discharge and corona discharge. This provides a new simpledevice for spark discharge research and is a supplement to the Townsend discharge experiment.
Function representation with circle inversion map systems
Boreland, Bryson; Kunze, Herb
2017-01-01
The fractals literature develops the now well-known concept of local iterated function systems (using affine maps) with grey-level maps (LIFSM) as an approach to function representation in terms of the associated fixed point of the so-called fractal transform. While originally explored as a method to achieve signal (and 2-D image) compression, more recent work has explored various aspects of signal and image processing using this machinery. In this paper, we develop a similar framework for function representation using circle inversion map systems. Given a circle C with centre õ and radius r, inversion with respect to C transforms the point p˜ to the point p˜', such that p˜ and p˜' lie on the same radial half-line from õ and d(õ, p˜)d(õ, p˜') = r2, where d is Euclidean distance. We demonstrate the results with an example.
CHARACTERISTICS OF HYDROCARBON EXPLOITATION IN ARCTIC CIRCLE
Directory of Open Access Journals (Sweden)
Vanja Lež
2013-12-01
Full Text Available The existence of large quantities of hydrocarbons is supposed within the Arctic Circle. Assumed quantities are 25% of the total undiscovered hydrocarbon reserves on Earth, mostly natural gas. Over 500 major and minor gas accumulations within the Arctic Circle were discovered so far, but apart from Snøhvit gas field, there is no commercial exploitation of natural gas from these fields. Arctic gas projects are complicated, technically hard to accomplish, and pose a great threat to the return of investment, safety of people and equipment and for the ecosystem. Russia is a country that is closest to the realization of the Arctic gas projects that are based on the giant gas fields. The most extreme weather conditions in the seas around Greenland are the reason why this Arctic region is the least explored and furthest from the realization of any gas project (the paper is published in Croatian .
Morphometric analysis of Willis circle arteries
Directory of Open Access Journals (Sweden)
Alma Voljevica
2013-01-01
Full Text Available Introduction: Willis arterial circle (circulus arteriosus cerebri Willisi is the most important part of the collateral circulatory system of the brain. It functions in normal and pathological situations such as valvular mechanism and thus allows optimal blood supply of all parts of the brain tissue, which reduces the risk of transient ischemic attack (TIA and stroke. The main pre-requisite for the normal function of the circle is its completeness and the lack of hypoplastic vessels. Materials and Methods: In this research, we used 100 angiograms of carotid system shown by serial angiography by Seldinger taken from the archives of the Department of Radiology, Clinical Center University of Sarajevo. For morphometric analysis of blood vessels, we used specially designed software program ELLIPSE (ViDiTo, Zoltan Tomoris, Kosice, Slovak Republic, tomori@saske.sk. In this way, it was possible to more easily store and analyze angiograms that were used for morphometric analysis. Results: In our study, larger diameters of blood vessels in Willis circle were observed in the younger subjects compared to older except the diameter of the internal carotid artery, which was about 0.2 to 0.3 mm larger in the older subjects. In both age groups among males, we recorded larger diameters of the internal carotid artery and segment before the circle of the posterior cerebral artery in relation to the female population, while the rear communicating artery in females was 0.1 mm wider in diameter compared to men in category of younger respondents.
The Bakhtin Circle and Applied Linguistics
Directory of Open Access Journals (Sweden)
Newton Duarte Molon
2012-11-01
Full Text Available This article aims at presenting the relations between the theoretical formulations of the Bakhtin Circle and the current discussion on the scope of the so called Applied Linguistics (AL. In order to do that, we will briefly outline the history of AL, present the main conceptions of the Bakhtin Circle‟s thought, and build possible dialogues between the theoretical formulations of the Russian thinkers and the main issues of the current debate in Applied Linguistics.
Rolling circle amplification of metazoan mitochondrialgenomes
Energy Technology Data Exchange (ETDEWEB)
Simison, W. Brian; Lindberg, D.R.; Boore, J.L.
2005-07-31
Here we report the successful use of rolling circle amplification (RCA) for the amplification of complete metazoan mt genomes to make a product that is amenable to high-throughput genome sequencing techniques. The benefits of RCA over PCR are many and with further development and refinement of RCA, the sequencing of organellar genomics will require far less time and effort than current long PCR approaches.
The life cycle and life span of Namibian fairy circles.
Tschinkel, Walter R
2012-01-01
In Namibia of southwestern Africa, the sparse grasslands that develop on deep sandy soils under rainfall between 50 and 100 mm per annum are punctuated by thousands of quasi-circular bare spots, usually surrounded by a ring of taller grass. The causes of these so-called "fairy circles" are unknown, although a number of hypotheses have been proposed. This paper provides a more complete description of the variation in size, density and attributes of fairy circles in a range of soil types and situations. Circles are not permanent; their vegetative and physical attributes allow them to be arranged into a life history sequence in which circles appear (birth), develop (mature) and become revegetated (die). Occasionally, they also enlarge. The appearance and disappearance of circles was confirmed from satellite images taken 4 years apart (2004, 2008). The frequency of births and deaths as a fraction of the total population of circles allowed the calculation of an approximate turnover rate, and from this, an estimate of circle lifespan. Lifespan appeared to vary with circle size, with small circles averaging about 24 years, and larger ones 43-75 years. Overall lifespan averaged about 41 yr. A second, independent estimate of lifespan was made by revisiting circles 2 to 9 years after their clear status had been confirmed. This resulted in a lifespan estimate of about 60 years. Any causal explanation of fairy circles must include their birth, development and death, their mean lifespan and the variation of their features under different conditions.
The life cycle and life span of Namibian fairy circles.
Directory of Open Access Journals (Sweden)
Walter R Tschinkel
Full Text Available In Namibia of southwestern Africa, the sparse grasslands that develop on deep sandy soils under rainfall between 50 and 100 mm per annum are punctuated by thousands of quasi-circular bare spots, usually surrounded by a ring of taller grass. The causes of these so-called "fairy circles" are unknown, although a number of hypotheses have been proposed. This paper provides a more complete description of the variation in size, density and attributes of fairy circles in a range of soil types and situations. Circles are not permanent; their vegetative and physical attributes allow them to be arranged into a life history sequence in which circles appear (birth, develop (mature and become revegetated (die. Occasionally, they also enlarge. The appearance and disappearance of circles was confirmed from satellite images taken 4 years apart (2004, 2008. The frequency of births and deaths as a fraction of the total population of circles allowed the calculation of an approximate turnover rate, and from this, an estimate of circle lifespan. Lifespan appeared to vary with circle size, with small circles averaging about 24 years, and larger ones 43-75 years. Overall lifespan averaged about 41 yr. A second, independent estimate of lifespan was made by revisiting circles 2 to 9 years after their clear status had been confirmed. This resulted in a lifespan estimate of about 60 years. Any causal explanation of fairy circles must include their birth, development and death, their mean lifespan and the variation of their features under different conditions.
Salaberria, Itziar; Perallos, Asier; Azpilicueta, Leire; Falcone, Francisco; Carballedo, Roberto; Angulo, Ignacio; Elejoste, Pilar; Bahillo, Alfonso; Astrain, José Javier; Villadangos, Jesús
2014-05-05
During the last years, the application of different wireless technologies has been explored in order to enable Internet connectivity from vehicles. In addition, the widespread adoption of smartphones by citizens represents a great opportunity to integrate such nomadic devices inside vehicles in order to provide new and personalized on trip services for passengers. In this paper, a proposal of communication architecture to provide the ubiquitous connectivity needed to enhance the smart train concept is presented and preliminarily tested. It combines an intra-wagon communication system based on nomadic devices connected through a Bluetooth Piconet Network with a highly innovative train-to-ground communication system. In order to validate this communication solution, several tests and simulations have been performed and their results are described in this paper.
Directory of Open Access Journals (Sweden)
Itziar Salaberria
2014-05-01
Full Text Available During the last years, the application of different wireless technologies has been explored in order to enable Internet connectivity from vehicles. In addition, the widespread adoption of smartphones by citizens represents a great opportunity to integrate such nomadic devices inside vehicles in order to provide new and personalized on trip services for passengers. In this paper, a proposal of communication architecture to provide the ubiquitous connectivity needed to enhance the smart train concept is presented and preliminarily tested. It combines an intra-wagon communication system based on nomadic devices connected through a Bluetooth Piconet Network with a highly innovative train-to-ground communication system. In order to validate this communication solution, several tests and simulations have been performed and their results are described in this paper.
Salaberria, Itziar; Perallos, Asier; Azpilicueta, Leire; Falcone, Francisco; Carballedo, Roberto; Angulo, Ignacio; Elejoste, Pilar; Bahillo, Alfonso; Astrain, José Javier; Villadangos, Jesús
2014-01-01
During the last years, the application of different wireless technologies has been explored in order to enable Internet connectivity from vehicles. In addition, the widespread adoption of smartphones by citizens represents a great opportunity to integrate such nomadic devices inside vehicles in order to provide new and personalized on trip services for passengers. In this paper, a proposal of communication architecture to provide the ubiquitous connectivity needed to enhance the smart train concept is presented and preliminarily tested. It combines an intra-wagon communication system based on nomadic devices connected through a Bluetooth Piconet Network with a highly innovative train-to-ground communication system. In order to validate this communication solution, several tests and simulations have been performed and their results are described in this paper. PMID:24803192
Convex functions and the rolling circle criterion
1995-01-01
Given 0≤R1≤R2≤∞, CVG(R1,R2) denotes the class of normalized convex functions f in the unit disc U, for which ∂f(U) satisfies a Blaschke Rolling Circles Criterion with radii R1 and R2. Necessary and sufficient conditions for R1=R2, growth and distortion theorems for CVG(R1,R2) and rotation theorem for the class of convex functions of bounded type, are found.
Arabia: from craters to stone circles
Sparavigna, Amelia Carolina
2010-01-01
The Arabia Shield has a volcanic nature inside. A region of the Western Saudi Arabia is in fact covered with vast fields of lava known as harraat. These lands are spotted by many stone circles and other quite interesting archaeological remains of the Neolithic period, such as the "desert kites", the hunters used to guide the game across the harrah in some corrals. With Google Maps, we can observe both sceneries, the volcanic nature of the land and a portrait of Arabia during the Neolithic times.
A mechanism for ramified rolling circle amplification
Directory of Open Access Journals (Sweden)
Smith James H
2010-12-01
Full Text Available Abstract Background Amplification of single-stranded DNA circles has wide utility for a variety of applications. The two-primer ramified rolling circle amplification (RAM reaction provides exponential DNA amplification under isothermal conditions, creating a regular laddered series of double-stranded DNA products. However, the molecular mechanism of the RAM reaction remains unexplained. Results A RAM reaction model predicts exponential accumulation of a double-stranded DNA product size series, and product-size ratios, that are consistent with observed RAM reaction products. The mechanism involves generation of a series of increasing size intermediate templates; those templates produce RAM products and recursively generate smaller intermediate templates. The model allows prediction of the number of rounds of circular template replication. Real-time RAM reaction data are consistent with the model. Analysis of RAM reaction products shows exponential growth limitation consistent with the model's predictions. Conclusions The model provides a rationale for the observed products of the RAM reaction, and the molecular yield among those products. Experimental results are consistent with the model.
Estimation of pure qubits on circles
Braunstein, S L; Severini, S; Braunstein, Samuel L.; Ghosh, Sibasish; Severini, Simone
2004-01-01
Gisin and Popescu [PRL, 83, 432 (1999)] have shown that more information about their direction can be obtained from a pair of anti-parallel spins compared to a pair of parallel spins, where the first member of the pair (which we call the pointer member) can point equally along any direction in the Bloch sphere. They argued that this was due to the difference in dimensionality spanned by these two alphabets of states. Here we consider similar alphabets, but with the first spin restricted to a fixed small circle of the Bloch sphere. In this case, the dimensionality spanned by the anti-parallel versus parallel alphabet is now equal. However, the anti-parallel alphabet is found to still contain more information in general. We generalize this to having N parallel spins and M anti-parallel spins. When the pointer member is restricted to a small circle these alphabets again span spaces of equal dimension, yet in general, more directional information can be found for sets with smaller |N-M| for any fixed total number...
Institute of Scientific and Technical Information of China (English)
闫颖
2015-01-01
当今世界各国铁路货车采用的检修制度,可以分为计划预防检修制度和按技术状态检修制度两大类型.神华铁路目前实施"日常检查、定期检修"的预防性计划修检修制度.然而,随着新型铁路货车不断投入使用及现有铁路货车改造完成,现行计划修检修模式中存在的问题日益凸显.因此,本文探讨运用大数据技术,通过集合神华铁路既有信息及监测系统数据,初步搭建神华铁路货车大数据平台,深度挖掘铁路货车检修相关数据,逐步实现神华铁路货车状态修.%At present,the maintenance system of wagon in the world can be divided into two major types:planed preventive maintenance system and technical condition-based maintenance system.Shenhua adopt dai-ly inspection and regular repairment.With continuous purchasing of new type of wagons and the transforma-tion of existing railway trucks,the problems in the maintenance mode are increasingly prominent.Therefore,this paper discusses the use of big data technology,the acquisition of Shenhua railway information and moni-toring system,the construction of the Shenhua wagon big data platform,the excavation wagon repairing related data,to realize condition-based maintenance system gradually.
Neurodynamics in Randomly Coupled Circle Maps
Matsuno, Tetsuya; Toko, Kiyoshi; Yamafuji, Kaoru
1996-05-01
The dynamics of retrieval processes in a system composed of coupled circle maps is studied by means of a statistical method and numerical simulations. Phase patterns are embedded in coupling parameters so that the system may work as an associative memory system. A parameter, which is an amplification factor multiplied to all the coupling strengths, is introduced for investigating the effect of the strength of the coupling nonlinearity on the behavior of the system concerned. The statistical method provides a set of time evolution equations representing the macroscopic behavior. It is found that the storage capacity is considerably enhanced by the introduced amplification factor. It is also shown that the system exhibits macroscopic chaotic oscillations when the strength of the coupling is sufficiently large. Moreover, the clustering is observed, as in other types of the globally coupled nonlinear systems.
Controlled Microwave Heating Accelerates Rolling Circle Amplification.
Yoshimura, Takeo; Suzuki, Takamasa; Mineki, Shigeru; Ohuchi, Shokichi
2015-01-01
Rolling circle amplification (RCA) generates single-stranded DNAs or RNA, and the diverse applications of this isothermal technique range from the sensitive detection of nucleic acids to analysis of single nucleotide polymorphisms. Microwave chemistry is widely applied to increase reaction rate as well as product yield and purity. The objectives of the present research were to apply microwave heating to RCA and indicate factors that contribute to the microwave selective heating effect. The microwave reaction temperature was strictly controlled using a microwave applicator optimized for enzymatic-scale reactions. Here, we showed that microwave-assisted RCA reactions catalyzed by either of the four thermostable DNA polymerases were accelerated over 4-folds compared with conventional RCA. Furthermore, the temperatures of the individual buffer components were specifically influenced by microwave heating. We concluded that microwave heating accelerated isothermal RCA of DNA because of the differential heating mechanisms of microwaves on the temperatures of reaction components, although the overall reaction temperatures were the same.
Fast transport optimization on the circle
Delon, Julie; Sobolevskii, Andrei
2009-01-01
Consider the problem of optimally matching two measures on the circle, or equivalently two periodic measures on the real line, and suppose the cost of matching two points satisfies the Monge condition. We introduce a notion of locally optimal transport plan, motivated by the weak KAM (Aubry-Mather) theory, and show that all locally optimal transport plans are conjugate to shifts. This theory is applied to a transportation problem arising in image processing: for two sets of point masses, both of which have the same total mass, find an optimal transport plan with respect to a given cost function that satisfies the Monge condition. For the case of N real-valued point masses we present an O(N log epsilon) algorithm that approximates the optimal cost within epsilon; when all masses are integer multiples of 1/M, the algorithm gives an exact solution in O(N log M) operations.
The Japanese Quality Control Circle: Why It Works.
Watanabe, Susumu
1991-01-01
The competitiveness of Japanese industry is in part because of their quality circles. Despite the West's interest in most Japanese business practices, quality circles have been difficult to transplant. This may be a result of misconceptions about their nature and the erroneous idea that workers' motivation is sociocultural, whereas in fact it is…
D'Nealian Handwriting versus Circle-Stick Print.
Thurber, Donald N.
This paper argues against teaching children to make letters using circle-stick writing. It contends that the circle-stick method requires continued pen/pencil lifts hindering rhythm or flow in the writing process and that there is little carry-over value into cursive writing as the two scripts are totally different. D'Nealian print, one type of…
The Vienna circles: cultivating economic knowledge outside academia
E. Dekker (Erwin)
2014-01-01
markdownabstract__Abstract__ This article examines the intellectual scenery of interwar Vienna. It argues that its central institution was not academia, but rather the circles (‘Kreise’). The prominence of these circles can partly account for the creative outburst in the social sciences in interwar
Integrating Literature Circles into a Cotaught Inclusive Classroom
Whittaker, Catharine R.
2012-01-01
Literature circles or book clubs are small, heterogeneous groups of students who have chosen to read and discuss the same book together. The research on literature circles suggests that they hold great promise for increasing students' enjoyment of reading and honing their literacy skills. When evidence-based strategies are embedded into a…
Locating a circle on the plane using the minimax criterion
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Schöbel, Anita
2009-01-01
We consider the problem of locating a circle with respect to existing facilities on the plane, such that the largest weighted distance between the circumference of the circle and the facilities is minimized. The problem properties are analyzed, and a solution procedure proposed...
Geometric fit of a point set by generalized circles
DEFF Research Database (Denmark)
Körner, Mark-Christopher; Brimberg, Jack; Juel, Henrik;
2010-01-01
In our paper we approximate a set of given points by a general circle. More precisely, given two norms k 1 and k 2 and a set of points in the plane, we consider the problem of locating and scaling the unit circle of norm k 1 such that the sum of weighted distances between the circumference of the...
Locating a general minisum 'circle' on a plane
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Körner, Mark-Christoph
2011-01-01
We approximate a set of given points in the plane by the boundary of a convex and symmetric set which is the unit circle of some norm. This generalizes previous work on the subject which considers Euclidean circles only. More precisely, we examine the problem of locating and scaling the unit circ...
DNA circles with cruciforms from Isospora (Toxoplasma) gondii
Weijers, P.J.; Borst, P.; Overdulve, J.P.; Fase-Fowler, F.; Berg, Marlene van den
1984-01-01
We have isolated a closed circular duplex DNA fraction from the unicellular parasite Isospora (Toxoplasma) gondii and examined the purified DNA by electron microscopy. A major part of this circular DNA consists of 12-μm circles containing a cruciform with 0.5-μm tails. We also found 23-μm circles wi
Locating a circle on the plane using the minimax criterion
DEFF Research Database (Denmark)
Brimberg, Jack; Juel, Henrik; Schöbel, Anita
2009-01-01
We consider the problem of locating a circle with respect to existing facilities on the plane, such that the largest weighted distance between the circumference of the circle and the facilities is minimized. The problem properties are analyzed, and a solution procedure proposed...
El-Safty, Sherif A; Shenashen, Mohamed A; Sakai, Masaru; Elshehy, Emad; Halada, Kohmei
2015-12-06
Developing low-cost, efficient processes for recovering and recycling palladium, gold and cobalt metals from urban mine remains a significant challenge in industrialized countries. Here, the development of optical mesosensors/adsorbents (MSAs) for efficient recognition and selective recovery of Pd(II), Au(III), and Co(II) from urban mine was achieved. A simple, general method for preparing MSAs based on using high-order mesoporous monolithic scaffolds was described. Hierarchical cubic Ia3d wagon-wheel-shaped MSAs were fabricated by anchoring chelating agents (colorants) into three-dimensional pores and micrometric particle surfaces of the mesoporous monolithic scaffolds. Findings show, for the first time, evidence of controlled optical recognition of Pd(II), Au(III), and Co(II) ions and a highly selective system for recovery of Pd(II) ions (up to ~95%) in ores and industrial wastes. Furthermore, the controlled assessment processes described herein involve evaluation of intrinsic properties (e.g., visual signal change, long-term stability, adsorption efficiency, extraordinary sensitivity, selectivity, and reusability); thus, expensive, sophisticated instruments are not required. Results show evidence that MSAs will attract worldwide attention as a promising technological means of recovering and recycling palladium, gold and cobalt metals.
Gosálvez, M. A.; Pal, Prem; Ferrando, N.; Hida, H.; Sato, K.
2011-12-01
This is part I of a series of two papers dedicated to the presentation of a novel, large throughput, experimental procedure to determine the three-dimensional distribution of the etch rate of silicon in a wide range of anisotropic etchants, including a total of 30 different etching conditions in KOH, KOH+IPA, TMAH and TMAH+Triton solutions at various concentrations and temperatures. The method is based on the use of previously reported, vertically micromachined wagon wheels (WWs) (Wind and Hines 2000 Surf. Sci. 460 21-38 Nguyen and Elwenspoek 2007 J. Electrochem. Soc. 154 D684-91), focusing on speeding up the etch rate extraction process for each WW by combining macrophotography and image processing procedures. The proposed procedure positions the WWs as a realistic alternative to the traditional hemispherical specimen. The obtained, extensive etch rate database is used to perform wet etching simulations of advanced systems, showing good agreement with the experimental counterparts. In part II of this series (Gosálvez et al J. Micromech. Microeng. 21 125008), we provide a theoretical analysis of the etched spoke shapes, a detailed comparison to the etch rates from previous studies and a self-consistency study of the measured etch rates against maximum theoretical values derived from the spoke shape analysis.
Androgen circle of polycystic ovary syndrome.
Homburg, Roy
2009-07-01
Although the aetiology of polycystic ovary syndrome (PCOS) is still not known and the search for causative genes is proving elusive, it is generally agreed that hyperandrogenism is at the heart of the syndrome. Here, it is proposed that excess androgens are the root cause of PCOS starting from their influence on the female fetus in programming gene expression, producing the characteristic signs and symptoms which are then exacerbated by a propagation of excess ovarian androgen production from multiple small follicles, anovulation and insulin resistance in the reproductive life-span, thus setting up a vicious perpetual circle of androgen excess. This opinion paper, rather than being a full-scale review, is intentionally biased in support of this hypothesis that androgen excess is the 'root of all evil' in PCOS; in the hope that its acceptance could lead to more direct treatment of the syndrome in all its facets rather than the symptomatic treatment of side effects of androgen excess that we are addressing today.
Inhomogeneous field theory inside the arctic circle
Allegra, Nicolas; Dubail, Jérôme; Stéphan, Jean-Marie; Viti, Jacopo
2016-05-01
Motivated by quantum quenches in spin chains, a one-dimensional toy-model of fermionic particles evolving in imaginary-time from a domain-wall initial state is solved. The main interest of this toy-model is that it exhibits the arctic circle phenomenon, namely a spatial phase separation between a critically fluctuating region and a frozen region. Large-scale correlations inside the critical region are expressed in terms of correlators in a (euclidean) two-dimensional massless Dirac field theory. It is observed that this theory is inhomogenous: the metric is position-dependent, so it is in fact a Dirac theory in curved space. The technique used to solve the toy-model is then extended to deal with the transfer matrices of other models: dimers on the honeycomb and square lattice, and the six-vertex model at the free fermion point (Δ =0 ). In all cases, explicit expressions are given for the long-range correlations in the critical region, as well as for the underlying Dirac action. Although the setup developed here is heavily based on fermionic observables, the results can be translated into the language of height configurations and of the gaussian free field, via bosonization. Correlations close to the phase boundary and the generic appearance of Airy processes in all these models are also briefly revisited in the appendix.
Controlled Microwave Heating Accelerates Rolling Circle Amplification.
Directory of Open Access Journals (Sweden)
Takeo Yoshimura
Full Text Available Rolling circle amplification (RCA generates single-stranded DNAs or RNA, and the diverse applications of this isothermal technique range from the sensitive detection of nucleic acids to analysis of single nucleotide polymorphisms. Microwave chemistry is widely applied to increase reaction rate as well as product yield and purity. The objectives of the present research were to apply microwave heating to RCA and indicate factors that contribute to the microwave selective heating effect. The microwave reaction temperature was strictly controlled using a microwave applicator optimized for enzymatic-scale reactions. Here, we showed that microwave-assisted RCA reactions catalyzed by either of the four thermostable DNA polymerases were accelerated over 4-folds compared with conventional RCA. Furthermore, the temperatures of the individual buffer components were specifically influenced by microwave heating. We concluded that microwave heating accelerated isothermal RCA of DNA because of the differential heating mechanisms of microwaves on the temperatures of reaction components, although the overall reaction temperatures were the same.
Varga, Richard S
2004-01-01
TheGer? sgorin CircleTheorem, averywell-known resultin linear algebra today, stems from the paper of S. Ger? sgorin in 1931 (which is reproduced in AppendixD)where,givenanarbitraryn×ncomplexmatrix,easyarithmetic operationsontheentriesofthematrixproducendisks,inthecomplexplane, whose union contains all eigenvalues of the given matrix. The beauty and simplicity of Ger? sgorin’s Theorem has undoubtedly inspired further research in this area, resulting in hundreds of papers in which the name “Ger? sgorin” appears. The goal of this book is to give a careful and up-to-date treatment of various aspects of this topic. The author ?rst learned of Ger? sgorin’s results from friendly conversations with Olga Taussky-Todd and John Todd, which inspired me to work in this area.Olgawasclearlypassionateaboutlinearalgebraandmatrixtheory,and her path-?nding results in these areas were like a magnet to many, including this author! It is the author’s hope that the results, presented here on topics related to Ger? sgorin...
Design and Calculation of the Resistance Circles for Wooden Barrels
Directory of Open Access Journals (Sweden)
Adriana FOTIN
2011-03-01
Full Text Available The aim of this paper is to present a design methodology for the circles of wooden barrels, usingappropriate strength calculations, so as to provide tightness while maintaining the integrity of the woodenmaterial embedded in the barrel structure, in the jacket and bottom staves, respectively.Based on these calculations, the circle dimensions (length, width and thickness can be defined,depending on the barrel type (for transport or storage and their relation to the barrel bottoms.Defining the dimensional characteristics of the circles is mandatory, as these are safety elements in thebarrel operation.
Yang-Lee Circle Theorem for an Antiferromagnetic Heisenberg Ladder
Institute of Scientific and Technical Information of China (English)
王先智
2001-01-01
The Yang-Lee zeros of an antiferromagnetic Heisenberg ladder model are determined. It is found that if J4≤0 Yang-Lee zeros are located on the unit circle and on the negative real axis in the complex activity plane. In particular, if J4≤0 and 2J2≥J4, Yang-Lee zeros are located on the unit circle and the Yang-Lee circle theorem is valid. If J4 ＞ 0, Yang-Lee zeros are located on some complicated curves.
The Euler Line and Nine-Point-Circle Theorems.
Eccles, Frank M.
1999-01-01
Introduces the Euler line theorem and the nine-point-circle theorem which emphasize transformations and the power of functions in a geometric concept. Presents definitions and proofs of theorems. (ASK)
Circle of Life——Symbolism in The Winter's Tale
Institute of Scientific and Technical Information of China (English)
李潇雨
2007-01-01
This essay tries to illustrate Winter's Tale's symbolic meaning about human life.It draws conclusion that Shakespeare's plan is to combine the natural rule of seasonal cycle with the life circle of human world.
Bounded Gain of Energy on the Breathing Circle Billiard
Oliffson-Kamphorst, S; Kamphorst, Sylvie Oliffson; Carvalho, Sonia Pinto de
1998-01-01
The Breathing Circle is a 2-dimensional generalization of the Fermi Accelerator. It is shown that the billiard map associated to this model has invariant curves in phase space, implying that any particle will have bounded gain of energy.
Optimal impulsive ellipse-to-circle coplanar rendezvous
Institute of Scientific and Technical Information of China (English)
无
2009-01-01
The problem of ellipse-to-circle coplanar rendezvous with chaser spacecraft in low eccentricity was investigated in this paper.With reference frame established in the centroid of the target spacecraft,the process of ellipse-to-circle coplanar rendezvous was described by the relative equations based on cy-lindrical reference frame,and then the solutions and distributions of optimal rendezvous models of a kind of close ellipse-to-circle coplanar rendezvous were provided.The simulation results showed that the guidance law based on the optimal rendezvous model in this research has good performance,and that the distributions of optimal rendezvous models of ellipse-to-circle coplanar rendezvous with the chaser spacecraft in low eccentricity are similar,albeit with slight difference,to those of rendezvous between close circular orbits.The work in this paper is a useful extension to Prussing’s optimal ren-dezvous theory between close circular orbits.
The Blaschke conjecture and great circle fibrations of spheres
2001-01-01
We construct an explicit diffeomorphism taking any fibration of a sphere by great circles into the Hopf fibration, using elementary geometry--indeed the diffeomorphism is a local (differential) invariant, algebraic in derivatives.
Parhelic-like circle from light scattering in Plateau borders
Energy Technology Data Exchange (ETDEWEB)
Tufaile, A., E-mail: tufaile@usp.br; Tufaile, A.P.B.
2015-03-06
We are reporting a new simple optical element to generate halos. We have observed interesting patterns of light scattering in Plateau borders in foams. In analogy to the atmospheric phenomena known as parhelic circle, sun dogs, and sun pillars, we have named the features of the patterns observed as parlaseric circle, laser dogs, and laser pillars. The triangular symmetry of the Plateau borders is analogous to the hexagonal symmetry of ice crystals which produce these atmospheric phenomena. Working with one Plateau border at a time, we have observed wave optics phenomena that are not perceived in the atmospheric phenomena, such as diffraction and interference. - Highlights: • We obtained halo formation from light scattering in a Plateau border using an experiment. • We explained halo formation using geometrical theory of diffraction. • An optical element based on a Plateau border is proposed. • We compared some aspects of the parhelic circle with the parlaseric circle.
Empirical Evaluation of Different Feature Representations for Social Circles Detection
2015-06-16
Kaggle competition on learning social circles in networks [5]. The data consist of hand- labelled friendship egonets from Facebook and a set of 57...study and compare the performance on the available labelled Facebook data from the Kaggle competition on learning social circles in networks. We...from both structural egonet information and user profile features. We study and compare the performance on the available labelled Facebook data from
Biology coming full circle: joining the whole and the parts.
Wikswo, John P; Porter, Andrew P
2015-01-01
The new cover of Experimental Biology and Medicine features the hermeneutic circle of biology, a concept we have adapted from the hermeneutic principle that one understands the whole only in terms of each part and the parts only in terms of the whole. Our hermeneutic circle summarizes the course of experimental biology through 2500 years of the achievements of reductionist research (understanding the parts), which culminates in our ability to rapidly sequence the genome. Rather than returning along the same path in a constructionist approach that simply builds upon this knowledge, but in reverse, an alternative is to close the circle with synthetic constructions that seek to integrate the full complexity of biological and physiological systems (understanding the whole), of which organs-on-chips are one example. This closing of the circle cannot be a comprehensively accurate representation of biology, but it can be a synthetic one that effectively defines particular biological subsystems. The illustration of the hermeneutic circle of biology is also intended to suggest both the multiple cycles that may be required to reach such a synthesis and the expansion of the circle in an outward spiral as knowledge increases. Our commentary explains the symbolism of the new cover in a philosophical and scientific discussion.
C80B型车体结构的强度及模态分析%Strength and modal analysis on the structure of C80B wagon body
Institute of Scientific and Technical Information of China (English)
赵戈; 钟宇光; 张玄; 张磊
2013-01-01
以C80B型运煤专用敞车车体为研究对象，应用Pro/E软件建立三维几何模型。在有限元的理论基础上，论述了车体有限元模型的单元选取、网格划分及边界处理，然后在ANSYS软件中对车体进行静强度分析和模态分析。结果表明，该车型车体在各种工况载荷作用下，满足《铁道车辆强度设计及试验鉴定规范》要求，同时找出了车体的危险部位，为进一步改进敞车设计提供参考。%Taking the wagon body of C80B as the object of study, a 3-D geometrical model of the wagon body is set up by software PRO/E. This paper discusses the selection, meshing and boundary processing of the body’s finite element model based on the Finite Element Theory. The static strength analysis and modal analysis of the body are conducted with the software ANSYS. The results showed that the vehicle body meets the requirements of the strength design of railway vehicles and test code for identification. At the same time, the dangerous parts of the car-body are found out, providing references for further improving wagon car design.
Institute of Scientific and Technical Information of China (English)
牟峰; 王慈光
2012-01-01
The wagon's takeout and delivery scheduling system in railway freight station (WTDSS) is a subsystem of railway station scheduling system, and its operation efficiency has a close bearing on the on-schedule rate of departure trains, wagon turnaround time and many other transportation production indexes. Based on the system optimization theory and methodology, the combinatorial mathematics theory, the set theory as well as some transportation production experiences, this dissertation analyzes the elements, structure, environment and characteristics of the wagon' s takeout and delivery scheduling system and studies modeling method, the construction method of model solution, optimization algorithm and heuristic methods for improving optimization efficiency of the wagon's delivery and takeout problem. The applicability of the research results has been validated by example. The main research contents and conclusions are as follows.(1) The operation objects, the loading-unloading locations and their layout forms, all kinds of takeout and delivery operations and their component elements, the operation organization modes are systematically analyzed in details. The WTDSS functional factors, environment and characteristics are comprehensively analyzed. The relevant concepts are clearly defined.(2) The wagon's delivery and takeout problem (WTDP) whose loading-unloading locations show radial layout (R-WTDP) is studied. Under the assumption that the locomotive haulage capacity and the wagon acceptance capacity of each loading-unloading location are both unlimited, the ideal mathematical models for the non-through and theunfixed form wagon flow are respectively established based on the fact that the sequence, moment and batch number problems of takeout and delivery operations during a period of time are a whole system. According to features of the models, expression method of the solution is designed, and modular implementation method for the models is proposed to construct
Three Concentric Circles: Young Chinese English Learners' Perceptions of Purposeful Audiences
Liu, Jack Jinghui
2015-01-01
English learners have more access to communicate with different purposeful audiences across the Three Concentric Circles of English (Kachu, 1985): the Inner Circle, the Outer Circle and the Expanding Circle. However, young language learners' purposeful audience as a focus of communication has not been emphasized as much as other linguistic…
Directory of Open Access Journals (Sweden)
Carlo Penco
2013-03-01
Full Text Available A discussion of The Vienna Circle and the Nordic Countries. Networks and Transformations of Logical Empiricism, edited by Juha Manninen and Friedrich Stadtler, Vienna Circle Institute Yearbook vol.14, Springer, 2010.
Circle Detection Using an Electromagnetism-Inspired Algorithm
Directory of Open Access Journals (Sweden)
Cuevas E.
2011-10-01
Full Text Available The Physic-inspired computation is becoming popular and has been acknowledged by the scientific community. This emerging area has developed a wide range of techniques and methods for dealing with complex problems. On the other hand, automatic circle detection in digital images has been considered as an important and complex task for the computer vision community that has devoted a tremendous amount of research seeking for an optimal circle detector. This article presents an algorithm for the automatic detection of circular shapes embedded into complicated and noisy images with no consideration of the conventional Hough transform techniques. The approach is based on a nature-inspired technique called the Electromagnetism- Like Optimization (EMO which is a heuristic method following electromagnetism principles for solving complex optimization problems. For the EMO algorithm, solutions are built considering the electromagnetic attraction and repulsion among charged particles with a charge representing the fitness solution for each particle. The algorithm uses the encoding of three non-collinear points as candidate circles over an edge-only image. Guided by the values of the objective function, the set of encoded candidate circles (charged particles are evolved using the EMO algorithm so that they can fit into the actual circles on the edge map of the image. Experimental results from several tests on synthetic and natural images with a varying range of complexity are included to validate the efficiency of the proposed technique regarding accuracy, speed, and robustness.
Talking Circles for Adolescent Girls in an Urban High School
Directory of Open Access Journals (Sweden)
Ann Schumacher
2014-10-01
Full Text Available Restorative Practices (RP in schools is a new and emerging field. Meeting in Circles to build friendships, develop emotional literacy skills, resolve conflict, or learn interactively are some of the core components of these programs. This article describes a 2-year study of 12 weekly Talking Circles organized under the auspices of a RP program in an urban high school with 60 adolescent girls. Primary data sources included 257 hr of participant observations in Talking Circles and individual, semi-structured interviews with 31 students. The Relational Cultural model, rooted in the work of Jean Baker Miller, served as the conceptual framework for understanding teens’ interactions within the Circle’s unique set of social conditions in a school environment. Findings demonstrated that Talking Circles provided a safe space for peers helping peers, and that the girls improved their listening, anger management, and empathic skills, which led to greater self-efficacy. It appears that Talking Circles could provide another venue for developing social-emotional literacy skills and growth-fostering relationships in schools.
An efficient circle detector not relying on edge detection
Cai, Jia; Huang, Panfeng; Chen, Lu; Zhang, Bin
2016-06-01
Accurate and efficient detection of circular modules fixed on non-cooperative target is a key technology for Tethered Space Robot. This paper presents an efficient circle detector based on region-growing of gradient and histogram distribution of Euclidean distance. Region-growing of gradient is applied to generate arc support regions from single point. And the corresponding square fitting areas are defined to accelerate the detection and decrease storage. A histogram is then used to count frequency of the distances that participates in the accumulator and the parameters of each circle are acquired. Finally, a verification strategy of circular integrity is designed to test the detection results. We have tested our algorithm on 35 images dealing with kinds of circles and ellipses. Experimental results demonstrate that our method is able to detect circular objects under occlusion, image noises and moderate shape deformations with a good precision.
A Personified Annealing Algorithm for Circles Packing Problem
Institute of Scientific and Technical Information of China (English)
ZHANGDe-Fu; LIXin
2005-01-01
Circles packing problem is an NP-hard problem and is difficult to solve. In this paper, a hybrid search strategy for circles packing problem is discussed. A way of generating new configuration is presented by simulating the moving of elastic objects, which can avoid the blindness of simulated annealing search and make iteration process converge fast. Inspired by the life experiences of people,an effective personified strategy to jump out of local minima is given. Based on the simulated annealing idea and personification strategy, an effective personified annealing algorithm for circles packing problem is developed. Numerical experiments on benchmark problem instances show that the proposed algorithm outperforms the best algorithm in the literature.
Circles Disturbed The Interplay of Mathematics and Narrative
Doxiadis, Apostolos
2012-01-01
Circles Disturbed brings together important thinkers in mathematics, history, and philosophy to explore the relationship between mathematics and narrative. The book's title recalls the last words of the great Greek mathematician Archimedes before he was slain by a Roman soldier--"Don't disturb my circles"--words that seem to refer to two radically different concerns: that of the practical person living in the concrete world of reality, and that of the theoretician lost in a world of abstraction. Stories and theorems are, in a sense, the natural languages of these two worlds--stories represent
Research Circles - a method for developing guidance practices
DEFF Research Database (Denmark)
2012-01-01
This video reports on our work with using research circles to improve our understanding of how to provide guidance and counseling to help young people in danger of dropping out of school. The video is based on the paper: Research Circles -- a method for developing guidance practices......, and was presented at the Conference for Social Justice, Prosperity and Sustainable Employment 2012 by assistant professor Helle Merete Nordentoft from DPU (http://edu.au.dk/). The film communicating the research paper was created by Mie Nørgaard...
A Phase Transition for Circle Maps and Cherry Flows
Palmisano, Liviana
2013-07-01
We study C 2 weakly order preserving circle maps with a flat interval. The main result of the paper is about a sharp transition from degenerate geometry to bounded geometry depending on the degree of the singularities at the boundary of the flat interval. We prove that the non-wandering set has zero Hausdorff dimension in the case of degenerate geometry and it has Hausdorff dimension strictly greater than zero in the case of bounded geometry. Our results about circle maps allow to establish a sharp phase transition in the dynamics of Cherry flows.
A Phase Transition for Circle Maps and Cherry Flows
Palmisano, Liviana
2012-01-01
We study $C^{2}$ weakly order preserving circle maps with a flat interval. The main result of the paper is about a sharp transition from degenerate geometry to bounded geometry depending on the degree of the singularities at the boundary of the flat interval. We prove that the non-wandering set has zero Hausdorff dimension in the case of degenerate geometry and it has Hausdorff dimension strictly greater than zero in the case of bounded geometry. Our results about circle maps allow to establish a sharp phase transition in the dynamics of Cherry flows.
Iterative-decreasing calibration method based on regional circle
Zhao, Hongyang
2017-07-01
In the field of computer vision, camera calibration is a hot issue. For the existing coupled problem of calculating distortion center and the distortion factor in the process of camera calibration, this paper presents an iterative-decreasing calibration method based on regional circle, uses the local area of the circle plate to calculate the distortion center coordinates by iterative declining, and then uses the distortion center to calculate the local area calibration factors. Finally, makes distortion center and the distortion factor for the global optimization. The calibration results show that the proposed method has high calibration accuracy.
Secure Two-Party Point-Circle Inclusion Problem
Institute of Scientific and Technical Information of China (English)
Yong-Long Luo; Liu-Sheng Huang; Hong Zhong
2007-01-01
Privacy-preserving computational geometry is a special secure multi-party computation and has many applica-tions.Previous protocols for determining whether a point is inside a circle are not secure enough.We present a two-round protocol for computing the distance between two private points and develop a more efficient protocol for the point-circle inclusion problem based on the distance protocol.In comparison with previous solutions, our protocol not only is more secure but also reduces the number of communication rounds and the number of modular multiplications significantly.
Types of the cerebral arterial circle (circle of Willis in a Sri Lankan Population
Directory of Open Access Journals (Sweden)
Gunasekera WSL
2011-01-01
Full Text Available Abstract Background The variations of the circle of Willis (CW are clinically important as patients with effective collateral circulations have a lower risk of transient ischemic attack and stroke than those with ineffective collaterals. The aim of the present cadaveric study was to investigate the anatomical variations of the CW and to compare the frequency of prevalence of the different variations with previous autopsy studies as variations in the anatomy of the CW as a whole have not been studied in the Indian subcontinent. Methods The external diameter of all the arteries forming the CW in 225 normal Sri Lankan adult cadaver brains was measured using a calibrated grid to determine the prevalence in the variation in CW. Chisquared tests and a correspondence analysis were performed to compare the relative frequencies of prevalence of anatomical variations in the CW across 6 studies of diverse ethnic populations. Results We report 15 types of variations of CW out of 22 types previously described and one additional type: hypoplastic precommunicating part of the anterior cerebral arteries (A1 and contralateral posterior communicating arteries (PcoA 5(2%. Statistically significant differences (p Conclusion The present study reveals that there are significant variations in the CW among intra and inter ethnic groups (Caucasian, African and Asian: Iran and Sri Lanka dominant populations, and warrants further studies keeping the methods of measurements, data assessment, and the definitions of hypoplasia the same.
Uncertainty budget for optical coordinate measurements of circle diameter
DEFF Research Database (Denmark)
Morace, Renate Erica; Hansen, Hans Nørgaard; De Chiffre, Leonardo
2004-01-01
An uncertainty analysis for circle diameter measurements using a coordinate measuring machine (CMM) equipped with an optical probe is presented in this paper. A mathematical model for data evaluation and uncertainty assessment was formulated in accordance with Guide to the Expression of Uncertain...
Arctic circles, domino tilings and square Young tableaux
Romik, Dan
2009-01-01
The arctic circle theorem of Jockusch, Propp, and Shor asserts that uniformly random domino tilings of an Aztec diamond of high order are frozen with asymptotically high probability outside the "arctic circle" inscribed within the diamond. A similar arctic circle phenomenon has been observed in the limiting behavior of random square Young tableaux. In this paper, we show that random domino tilings of the Aztec diamond are asymptotically related to random square Young tableaux in a more refined sense that looks also at the behavior inside the arctic circle. This is done by giving a new derivation of the limiting shape of the height function of a random domino tiling of the Aztec diamond that uses the large-deviation techniques developed for the square Young tableaux problem in a previous paper by Pittel and the author. The solution of the variational problem that arises for domino tilings is almost identical to the solution for the case of square Young tableaux by Pittel and the author. The analytic techniques...
Language Teachers through the Looking Glass: Expanding Circle Teachers' Discourse
Lovtsevich, Galina N.
2005-01-01
When English language teachers from Russia join in professional discourse with their counterparts from other countries, they do so in English, using a professional register which is, to a large extent, determined by language teaching theorists and practitioners in Inner Circle countries. This paper examines some of the issues surrounding…
An Approach for Self-Calibration by a Quartered Circle
Directory of Open Access Journals (Sweden)
Yue Zhao
2013-07-01
Full Text Available The camera calibration is a key step for converting a projective reconstruction into a metric one, which is equivalent to recovering the unknown intrinsic parameters with each image. A circle is a common geometric primitive for the camera self-calibration. To avoid the limit of circle center to the camera self-calibration in a planar template, a method how to solve out the vanishing line is proposed. Then using the property of vanishing line, the camera intrinsic parameters are figured out and the camera self-calibration is achieved. The template contains a quartered circle in the study. Firstly, the camera is used to take photographs of the template from three or more direction. Secondly, using the ellipse and two mutually perpendicular diameters which are extracted from the image, according to the polarity principle and making use of the invariant property of cross-ratio of four lines which are intersected in one same point, the vanishing line can be solved out. In the end, the circular points can be figured out by the intersection between vanishing line and the circle. And using the property of the circular points, the self-calibration is realized.
First Voice: The Circle of Courage and Independent Living
Reid, Jennifer S.; Ross, Jean W.
2005-01-01
Adolescents in foster care must have a voice and play an active role in envisioning and planning for successful adulthood. This principle serves as the philosophy of First Voice, a training package for anyone who works with youth in foster care. The philosophy corresponds with the four parts of the Circle of Courage--Independence, Belonging,…
The Area of a Polygon with an Inscribed Circle
Buck, Marshall W
2012-01-01
Heron's formula states that the area $K$ of a triangle with sides $a$, $b$, and $c$ is given by $$ K=\\sqrt {s(s-a) (s-b) (s-c)} $$ where $s$ is the semiperimeter $(a+b+c)/2$. Brahmagupta, Robbins, Roskies, and Maley generalized this formula for polygons of up to eight sides inscribed in a circle. In this paper we derive formulas giving the areas of any $n$-gon, with odd $n$, in terms of the ordered list of side lengths, if the $n$-gon is circumscribed about a circle (instead of being inscribed in a circle). Unlike the cyclic polygon problem, where the order of the sides does not matter, for the inscribed circle problem (our case) it does matter. The solution is much easier than for the cyclic polygon problem, but it does generalize easily to all odd $n$. We also provide necessary and sufficient conditions for there to be solutions in the case of even $n$.
Perturbative analysis of maps of the circle onto itself
Energy Technology Data Exchange (ETDEWEB)
Zanetti, G. (Bologna Univ. (Italy). Ist. di Fisica); Turchetti, G. (Bologna Univ. (Italy). Ist. di Fisica; Istituto Nazionale di Fisica Nucleare, Bologna (Italy))
1984-09-15
As a model problem for the perturbation, up to break up, of tori in Hamoltonian mechanics, the map of the circle into itself is studied. By using classical perturbative techniques, not only the subcritical dynamics is well reproduced, but also the critical point is sharply defined and the conjugacy break up via the loss of differentiability is obtained in agreement with Shenker.
Problem Posing and Problem Solving in a Math Teacher's Circle
Appleton, Eric; Farina, Solange; Holzer, Tyler; Kotelawala, Usha; Trushkowsky, Mark
2017-01-01
This article describes the New York City Community of Adult Math Instructors (CAMI), a math teachers' circle founded in November 2014. The authors share details about their own participation in CAMI to show the professional growth that research-based, peer-led professional development can offer for adult educators.
The magic of fairy circles: Built or created?
Sahagian, Dork
2017-05-01
Fairy circles are rings of relatively dense grass in arid regions with sparse vegetation. The most famous examples are found in the Namib Desert. There has been an ongoing debate regarding the origin of these features, and a recent paper by Ravi et al. (2017, doi:10.1002/2016JG003604) sheds some light on this situation.
Revisiting Cyberbullying in Schools Using the Quality Circle Approach
Paul, Simone; Smith, Peter K.; Blumberg, Herbert H.
2012-01-01
An earlier study reported the use of Quality Circles (QC) in a UK school in the context of understanding and reducing bullying and cyberbullying. Here, we report further work in the same school setting. The QC approach allows explorative analysis of problems in school settings, whereby students embark on a problem-solving exercise over a period of…
A geometrical link between the circle and sexagesimal system
Julca, Jaime Vladimir Torres-Heredia
2007-01-01
This paper presents a simple geometrical fact which could relate to the history of mathematics and astronomy. This fact shows a natural link between the circle and the multiples of 6 and it makes it possible to obtain a simple representation of the 12 months of the year, the 24 hours of the day, the 30 days (average number) of the month and the 360 days (approximate number) of the year, which brings us closer to the sexagesimal division of time. Moreover this representation reminds one of the movement of the planets around a centre. Using this fact one will be able also to find geometrically the principal divisor of number 60, to represent numbers in base 60 with a kind of abacus or calculation table and to make a division of the circle into 6 and 12 equal parts. Afterwards one will be able to obtain a division in 360 unequal parts but relatively close to one another, and the goal isn't precisely to obtain an optimal division of the circle in 360 equal parts but to prove that the idea to divide the circle in ...
Inclusive Teaching Circles: Mechanisms for Creating Welcoming Classrooms
Moore, Sharon; Wallace, Sherri L.; Schack, Gina; Thomas, M. Shelley; Lewis, Linda; Wilson, Linda; Miller, Shawnise; D'Antoni, Joan
2010-01-01
This essay examines the Inclusive Teaching Circle (ITC) as a mechanism for faculty development in creating instructional tools that embrace an inclusive pedagogy reflecting diversity, cultural competence and social justice. We describe one group's year-long participation in an ITC at a large, metropolitan research university in the south. Next, we…
Quantum Mechanics on the Circle and W_{1+\\INFTY}
Floreanini, R.; Percacci, R.; Sezgin, E.(George P. and Cynthia W. Mitchell Institute for Fundamental Physics and Astronomy, Texas A&M University, College Station, TX, 77843-4242, USA)
1991-01-01
The algebra W_{1+\\infty} with central charge c=0 can be identified with the algebra of quantum observables of a particle moving on a circle. Mathematically, it is the universal enveloping algebra of the Euclidean algebra in two dimensions. Similarly, the super W_\\infty algebra is found to be the universal enveloping algebra of the super-Euclidean algebra in two dimensions.
Circle Time for Social and Emotional Learning in Primary School
Cefai, Carmel; Ferrario, Erika; Cavioni, Valeria; Carter, Audrey; Grech, Tracy
2014-01-01
This paper discusses the findings and implications of a semi-randomised control trial study on the effectiveness of circle time (CT) on primary school students' social and emotional learning, as well as classroom teachers' and students' experience of CT. A social and emotional learning programme was delivered through CT by trained classroom…
Geometric calibration of the circle-plus-arc trajectory.
Hoppe, Stefan; Noo, Frédéric; Dennerlein, Frank; Lauritsch, Günter; Hornegger, Joachim
2007-12-07
In this paper, a novel geometric calibration method for C-arm cone-beam scanners is presented which allows the calibration of the circle-plus-arc trajectory. The main idea is the separation of the trajectory into two circular segments (circle segment and arc segment) which are calibrated independently. This separation makes it possible to reuse a calibration phantom which has been successfully applied in clinical environments to calibrate numerous routinely used C-arm systems. For each trajectory segment, the phantom is placed in an optimal position. The two calibration results are then combined by computing the transformation the phantom underwent between the independent calibration runs. This combination can be done in a post-processing step by using standard linear algebra. The method is not limited to circle-plus-arc trajectories and works for any calibration procedure in which the phantom has a preferred orientation with respect to a trajectory segment. Results are presented for both simulated as well as real data acquired with a C-arm system. We also present the first image reconstruction results for the circle-plus-arc trajectory using real C-arm data.
Outcomes and Accomplishments of The Circles of Care Planing Efforts
Duclos, Christine W.; Phillips, Mary; LeMaster, Pamela L.
2004-01-01
This paper presents outcomes and accomplishments of the first round of participating individuals, communities, and grantees of the Circles of Care program (CoC). While accomplishing all CoC program goals, the initiative supported grantees in developing individual service delivery system models and positioned each grantee advantageously for…
Is Russell's vicious circle principle false or meaningless?
Fleischhacker, L.E.
1979-01-01
P. Vardy asserts the thesis that the vicious circle principle has the same structure as Russell's paradox. But structure is not the thing itself. It is the thing objectivated from the wiewpoint of a mathematician. So this structure can be expressed in a mathematical formalism, e. g. the Λ-calculus.
A review of fast circle and helix fitting
Frühwirth, R; Waltenberger, W; Wroldsen, J
2003-01-01
Circle and helix fitting is of paramount importance in the data analysis of LHC experiments. We review several approaches to exact but fast fitting, including a recent development based on the projection of the measured points onto a second-order surface in space (a sphere or a paraboloid). We present results of a comparison with global and recursive linearized least-squares estimators.
Defining Leadership: Collegiate Women's Learning Circles: A Qualitative Approach
Preston-Cunningham, Tammie; Elbert, Chanda D.; Dooley, Kim E.
2017-01-01
The researchers employed qualitative methods to evaluate first-year female students' definition of "leadership" through involvement in the Women's Learning Circle. The findings revealed that students defined leadership in two dimensions: traits and behaviors. The qualitative findings explore a multidimensional approach to the voices of…
Maximum-likelihood estimation of circle parameters via convolution.
Zelniker, Emanuel E; Clarkson, I Vaughan L
2006-04-01
The accurate fitting of a circle to noisy measurements of circumferential points is a much studied problem in the literature. In this paper, we present an interpretation of the maximum-likelihood estimator (MLE) and the Delogne-Kåsa estimator (DKE) for circle-center and radius estimation in terms of convolution on an image which is ideal in a certain sense. We use our convolution-based MLE approach to find good estimates for the parameters of a circle in digital images. In digital images, it is then possible to treat these estimates as preliminary estimates into various other numerical techniques which further refine them to achieve subpixel accuracy. We also investigate the relationship between the convolution of an ideal image with a "phase-coded kernel" (PCK) and the MLE. This is related to the "phase-coded annulus" which was introduced by Atherton and Kerbyson who proposed it as one of a number of new convolution kernels for estimating circle center and radius. We show that the PCK is an approximate MLE (AMLE). We compare our AMLE method to the MLE and the DKE as well as the Cramér-Rao Lower Bound in ideal images and in both real and synthetic digital images.
The Circle of Courage and Erikson's Psychological Stages.
Coughlan, Felicity; Welsh-Breetzke, Andrea
2002-01-01
Describes the application of positive youth development principles to challenges faced by adolescent females in South Africa. A mainline, Euro-centric theory, Erikson's life stages (1963), is compared with the Circle of Courage model based on Native American Tribal wisdom. The differences and correlation in these approaches are explored through…
Literature Circles: A Perfect Match for Online Instruction
Whittingham, Jeff
2013-01-01
This article describes the author's search for an appropriate and satisfying online teaching method. After experimenting with several methods (chat room, discussion board, student led discussion), the author reached back to his face-to-face classroom success with literature circles. This article reports the results of research conducted by the…
Using Literature Circles to Discuss Social Justice in Teacher Education
Madhuri, Marga; Walker, Nancy; Landmann-Johnsey, Erica; Laughter, Judson
2015-01-01
Literacy educators feel it is incumbent on teacher preparation programs to prepare teacher candidates with the dispositions and competencies needed to work with students from diverse racial, cultural, and economic backgrounds. As a way to initiate the discussion and help candidates examine their own views on race, literature circles are used. The…
Majorization algorithms for inspecting circles, ellipses, squares, rectangles, and rhombi
K. van Deun; P.J.F. Groenen (Patrick)
2003-01-01
textabstractIn several disciplines, as diverse as shape analysis, location theory, quality control, archaeology, and psychometrics, it can be of interest to fit a circle through a set of points. We use the result that it suffices to locate a center for which the variance of the distances from the ce
Revisiting Cyberbullying in Schools Using the Quality Circle Approach
Paul, Simone; Smith, Peter K.; Blumberg, Herbert H.
2012-01-01
An earlier study reported the use of Quality Circles (QC) in a UK school in the context of understanding and reducing bullying and cyberbullying. Here, we report further work in the same school setting. The QC approach allows explorative analysis of problems in school settings, whereby students embark on a problem-solving exercise over a period of…
Defining Leadership: Collegiate Women's Learning Circles: A Qualitative Approach
Preston-Cunningham, Tammie; Elbert, Chanda D.; Dooley, Kim E.
2017-01-01
The researchers employed qualitative methods to evaluate first-year female students' definition of "leadership" through involvement in the Women's Learning Circle. The findings revealed that students defined leadership in two dimensions: traits and behaviors. The qualitative findings explore a multidimensional approach to the voices of…
Institute of Scientific and Technical Information of China (English)
无
2008-01-01
2010款CTS Sport Wagon是CTS的五门旅行版，具有Wagon的实用性和全新CTS的精悍造型，车体尺寸大致与轿车版相同，这款Sport Wagon使用了CTS的很多造型同时又增加尾部空间以使得它可以装载更多的东西。这个由Clay Dean领导的设计团队并不仅仅是给轿车加装了一个更长的车顶。他们将车顶线条延伸到了车尾，而尾灯也上升到了车顶，
Optimizing care in osteoporosis: The Canadian quality circle project
Directory of Open Access Journals (Sweden)
Kvern Brent
2008-10-01
Full Text Available Abstract Background While the Osteoporosis Canada 2002 Canadian guidelines provided evidence based strategies in preventing, diagnosing, and managing this condition, publication and distribution of guidelines have not, in and of themselves, been shown to alter physicians clinical approaches. We hypothesize that primary care physicians enrolled in the Quality Circle project would change their patient management of osteoporosis in terms of awareness of osteoporosis risk factors and bone mineral density testing in accordance with the guidelines. Methods The project consisted of five Quality Circle phases that included: 1 Training & Baseline Data Collection, 2 First Educational Intervention & First Follow-Up Data Collection 3 First Strategy Implementation Session, 4 Final Educational Intervention & Final Follow-up Data Collection, and 5 Final Strategy Implementation Session. A total of 340 circle members formed 34 quality circles and participated in the study. The generalized estimating equations approach was used to model physician awareness of risk factors for osteoporosis and appropriate utilization of bone mineral density testing pre and post educational intervention (first year of the study. Odds ratios (OR and 95% confidence intervals (95% CI were calculated. Results After the 1st year of the study, physicians' certainty of their patients' risk factor status increased. Certainty varied from an OR of 1.4 (95% CI: 1.1, 1.8 for prior vertebral fracture status to 6.3 (95% CI: 2.3, 17.9 for prior hip fracture status. Furthermore, bone mineral density testing increased in high risk as compared with low risk patients (OR: 1.4; 95% CI: 1.2, 1.7. Conclusion Quality Circle methodology was successful in increasing both physicians' awareness of osteoporosis risk factors and appropriate bone mineral density testing in accordance with the 2002 Canadian guidelines.
Braking optimization method of wagon under limit adhesion%货车极限黏着制动优化方法
Institute of Scientific and Technical Information of China (English)
戚壮; 李芾; 丁军君
2012-01-01
Based on the wheel/rail contact model of Polach's large creep theory, the creepage corresponding the saturated adhesion coefficient was determined in the brake condition of wagon. As block pressure was taken as the optimization objective and the creepage was taken as the objective function, vehicle dynamics model was built in SIMPACK environment under considering braking system. By ARX system identification, the reference system of creepage response was modelled in SIMULINK environment. On the purpose that the creepages of MBS model and reference model kept consistent during the brake, the creepage response was tracked by using MIT adaptive control technic, and an optimized method to apply block pressure was obtained. Compared with other ordinary methods, the optimized method decreases 71.6% of the maximal creepage and 11.8% of vehicle velocity at braking end, which can effectively eliminate wheel/rail slide and shorten the brake distance to a certain extent. 1 tab, 9 figs, 13 refs.%基于Polach大纵向蠕滑理论的轮轨接触模型，确定了铁道车辆在制动工况下，轮轨黏着系数达到饱和时的轮轨蠕滑率。以闸瓦压力为优化对象，以轮轨蠕滑率为目标函数，在SIMPACK环境下构建了考虑制动系统的车辆动力学模型。通过ARX系统辨识技术，在SIMULINK环境下构建了轮轨蠕滑率响应的参照系统。为了使车辆模型与参照模型的蠕滑率在制动过程中保持一致，基于MIT自适应控制技术对制动时车辆的蠕滑率响应进行了跟踪，以实现对闸瓦压力施加方案的优化。计算结果表明：与一般闸瓦压力施加方案比较，优化后的闸瓦压力使轮轨最大蠕滑率下降了71．6％，使制动结束时的车速下降了11．8％，说明优化后的闸瓦压力不但能有效避免轮轨间的擦伤，还能够在一定程度上缩短车辆的制动距离。
山元, 隆春; 居川, あゆ子
2013-01-01
In this paper, possibilities of the “Literature Circle" practice in native language classes were explored. By considering on Japanese Language Arts lessons using the idea of “Literature Circle", by one teacher, we found such lessons had effects to enhance students' appetite for learning and reading abilities. And we also suggested that the “Literature Circle" methodology would be effective to developing students' abilities for “criticizing any texts," then we must adapt “Literature Circle" in...
Are Namibian "fairy circles" the consequence of self-organizing spatial vegetation patterning?
Cramer, Michael D; Barger, Nichole N
2013-01-01
Causes of over-dispersed barren "fairy circles" that are often surrounded by ca. 0.5 m tall peripheral grasses in a matrix of shorter (ca. 0.2 m tall) grasses in Namibian grasslands remain mysterious. It was hypothesized that the fairy circles are the consequence of self-organizing spatial vegetation patterning arising from resource competition and facilitation. We examined the edaphic properties of fairy circles and variation in fairy circle size, density and landscape occupancy (% land surface) with edaphic properties and water availability at a local scale (<50 km) and with climate and vegetation characteristics at a regional scale. Soil moisture in the barren fairy circles declines from the center towards the periphery and is inversely correlated with soil organic carbon, possibly indicating that the peripheral grass roots access soil moisture that persists into the dry season within fairy circles. Fairy circle landscape occupancy is negatively correlated with precipitation and soil [N], consistent with fairy circles being the product of resource-competition. Regional fairy circle presence/absence is highly predictable using an empirical model that includes narrow ranges of vegetation biomass, precipitation and temperature seasonality as predictor variables, indicating that fairy circles are likely a climate-dependent emergent phenomenon. This dependence of fairy circle occurrence on climate explains why fairy circles in some locations may appear and disappear over time. Fairy circles are only over-dispersed at high landscape occupancies, indicating that inter-circle competition may determine their spacing. We conclude that fairy circles are likely to be an emergent arid-grassland phenomenon that forms as a consequence of peripheral grass resource-competition and that the consequent barren circle may provide a resource-reservoir essential for the survival of the larger peripheral grasses and provides a habitat for fossicking fauna.
Are Namibian "fairy circles" the consequence of self-organizing spatial vegetation patterning?
Directory of Open Access Journals (Sweden)
Michael D Cramer
Full Text Available Causes of over-dispersed barren "fairy circles" that are often surrounded by ca. 0.5 m tall peripheral grasses in a matrix of shorter (ca. 0.2 m tall grasses in Namibian grasslands remain mysterious. It was hypothesized that the fairy circles are the consequence of self-organizing spatial vegetation patterning arising from resource competition and facilitation. We examined the edaphic properties of fairy circles and variation in fairy circle size, density and landscape occupancy (% land surface with edaphic properties and water availability at a local scale (<50 km and with climate and vegetation characteristics at a regional scale. Soil moisture in the barren fairy circles declines from the center towards the periphery and is inversely correlated with soil organic carbon, possibly indicating that the peripheral grass roots access soil moisture that persists into the dry season within fairy circles. Fairy circle landscape occupancy is negatively correlated with precipitation and soil [N], consistent with fairy circles being the product of resource-competition. Regional fairy circle presence/absence is highly predictable using an empirical model that includes narrow ranges of vegetation biomass, precipitation and temperature seasonality as predictor variables, indicating that fairy circles are likely a climate-dependent emergent phenomenon. This dependence of fairy circle occurrence on climate explains why fairy circles in some locations may appear and disappear over time. Fairy circles are only over-dispersed at high landscape occupancies, indicating that inter-circle competition may determine their spacing. We conclude that fairy circles are likely to be an emergent arid-grassland phenomenon that forms as a consequence of peripheral grass resource-competition and that the consequent barren circle may provide a resource-reservoir essential for the survival of the larger peripheral grasses and provides a habitat for fossicking fauna.
Topographic control of sorted circle morphology on Svalbard
Voigt, Joana; Hauber, Ernst; Reiss, Dennis; Hiesinger, Harald; Johnsson, Andreas; van Gasselt, Stephan; Balme, Matt; Head, Jim; de Verra, Jean-Pierre; Steinbrügge, Gregor; Jaumann, Ralf
2015-04-01
Patterned ground is a typical phenomenon in polar, subpolar and alpine regions [1]. As it is commonly (but not necessarily!) related to freeze-thaw cycles, its presence on Mars could possibly point to locations and periods where and when liquid water existed in the recent past [2]. Sorted circles are a class of patterned ground that was tentatively identified in Elysium Planitia (Mars) [3], but this interpretation has been challenged on the basis of physical considerations [4]. Without direct access to potential patterned ground on Mars, the analysis of terrestrial analogues can inform the interpretation of Martian landforms. Svalbard (Norway) offers a wide variety of permafrost features that are morphologically analogous to Martian cold-climate landforms [5]. It hosts some of the best examples of sorted circles on Earth, which are located on the westernmost tip of Brøgger peninsula, on a broad strand flat that is characterized by a series of postglacial beach ridges [6]. Here we report on our analysis of sorted circle morphology (especially their plan-view shape, i.e. their "roundness" or ellipticity) and its correlation with local topography (slopes, curvature). Sorted circle morphology was determined from HRSC-AX images (for details on the flight campaign and image properties see ref [5]) and through field work. Topographic information comes from a 50 cm gridded DEM derived from HRSC-AX stereo images. We measured sorted circle morphology (ellipticity, azimuth of major axis) along a WNW-ESE traverse that runs from the inland towards the sea and is oriented perpendicular to the local beach ridge trend. Selected areas with homogeneous sorted circle appearance were visually mapped, and compared to the average slope, aspect, and the calculated topographic wetness index (TWI). Furthermore the whole traverse was classified into four different morphologies of the sorted patterned ground (sorted circles, sorted "ellipses", sorted nets and areas without patterned ground
The Chicken and the Egg: Inviting Response and Talk through Socratic Circles
Styslinger, Mary E.; Pollock, Timothy
2010-01-01
This collaborative inquiry answers the following questions: 1) What is the nature of talk during Socratic Circles? 2) What is student response to talk? 3) How might knowing more about student response to talk and the nature of talk improve teaching during Socratic Circles? The article first describes the process of implementing Socratic Circles,…
Native American Values and Management Education: Envisioning an Inclusive Virtuous Circle
Verbos, Amy Klemm; Gladstone, Joe S.; Kennedy, Deanna M.
2011-01-01
Circles are symbols of interconnectedness. Behavioral circles can be vicious or virtuous. Many American Indians are caught in a vicious circle of exclusion from the purported benefits of Westernization, entrapment in its negative elements, and the ongoing undermining of their culture and thus their identities. Yet Native Americans, along with many…
The Chicken and the Egg: Inviting Response and Talk through Socratic Circles
Styslinger, Mary E.; Pollock, Timothy
2010-01-01
This collaborative inquiry answers the following questions: 1) What is the nature of talk during Socratic Circles? 2) What is student response to talk? 3) How might knowing more about student response to talk and the nature of talk improve teaching during Socratic Circles? The article first describes the process of implementing Socratic Circles,…
Calculation of Latitude and Longitude for Points on Perimeter of a Circle on a Sphere
Energy Technology Data Exchange (ETDEWEB)
Morris, Heidi E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2015-08-14
This document describes the calculation of the Earth-Centered Earth Fixed (ECEF) coordinates for points lying on the perimeter of a circle. Here, the perimeter of the circle lies on the surface of the sphere and the center of the planar circle is below the surface. These coordinates are converted to latitude and longitude for mapping fields on the surface of the earth.
Oh, Hee
2010-01-01
We present recent results on counting and distribution of circles in a given circle packing invariant under a geometrically finite Kleinian group and discuss how the dynamics of flows on geometrically finite hyperbolic $3$ manifolds are related. Our results apply to Apollonian circle packings, Sierpinski curves, Schottky dances, etc.
From EUCLID to Ptolemy in English Crop Circles
Hawkins, G. S.
1997-12-01
The late Lord Soli Zuckerman, science advisor to several British governments, encouraged the author, an astronomer, to test the theory that all crop circles were made by hoaxers. Within the hundreds of formations in Southern England he saw a thread of surprising historical content at the intellectual level of College Dons. One diagram in celestial mechanics involved triple conjunctions of Mercury, Venus and Mars every 67 2/3 years. Ptolemy's fourth musical scale, tense diatonic, occurred in the circles during the period 1978-88. Starting on E, Ptolemaic ratios make our perfect diatonic scale of white notes on the keyboard of the piano or church organ. For separated circles the ratio was given by diameters, and for concentric circles it was diameters squared. A series of rotationally symmetric figures began in 1988 which combined Ptolemy's ratios with Euclid's theorems. In his last plane theorem, Euclid (Elements 13,12) proved that the square on the side of an equilateral triangle is 3 times the square on the circum-circle radius -- diatonic note G(2). From the 1988 figure one can prove the square on the side is 16/3 times the square on the semi-altitude, giving note F(3). Later rotational figures over the next 5 years led to diatonic ratios for the hexagon, square and triangle. They gave with the exactness of Euclidean theorems the notes F, C(2) and E(2), and they are the only regular polygons to do so. Although these 4 crop theorems derive from Euclid, they were previously unknown as a set in the literature, nor had the Ptolemaic connection been published. Professional magazines asked the readers to provide a fifth theorem that would generate the above 4 theorems, but none was forthcoming. Ultimately the cicle makers showed knowledge of this generating theorem using a 200-ft design at Litchfield, Hampshire. After 1993, rotationally symmetric geometries continued to appear, but with much more complicated patterns. One design showed 6 crescent moons in a hexagon
Directory of Open Access Journals (Sweden)
Paulo S. G. Magalhães
2008-06-01
Full Text Available Um dos problemas encontrados na colheita mecanizada da cana-de-açúcar é a falta de sincronismo entre a colhedora e o transbordo, ocasionando perdas tanto de material como de capacidade operacional. A presente pesquisa teve como objetivo desenvolver um sistema capaz de auxiliar no sincronismo entre a colhedora e o veículo de transbordo por meio de comunicação sem fio. Dois sensores de ultra-som acoplados ao elevador e um microprocessador gerenciam tais informações, gerando correta sincronia entre as máquinas. O sistema foi testado em laboratório e em campo, cumprindo corretamente a função de manter as máquinas em sincronia, indicando e alertando aos operadores as suas posições relativas. O sistema desenvolvido reduziu as perdas de rebolo em cerca de 60 kg ha-1, comparado com a colheita realizada com o sistema desligado.One of the problems found in mechanical harvest of sugar cane is the lack of synchronism between the harvest machine and the infield wagon, causing crop losses as well as operational capacity. The objective of the present research was to design a system capable of helping to synchronize the sugar cane harvest machine with the wagon. The communication between tractor and harvest machine is wireless. Two ultrasound sensors coupled to the elevator and a microprocessor manage such information, generating a correct synchronization among the machines. The system was tested in laboratory and on field performing its function adequately, maintaining the two machines in synchronization, indicating and alerting the operators their relative positions. The developed system reduced the sugar cane lost in 60 kg ha-1 comparing to the harvest with the system turned off.
Landscapes, Circles and Antikythera: The Birth of the Mechanical Universe
Edmunds, M. G.
The joint Greek/UK/US Antikythera Mechanism Research Project is currently producing a definitive set of experimental optical and X-ray imaging data of the Mechanism. The interpretation will require a good knowledge of the context in which it was made. Following from the sacred landscapes of northern Europe it is difficult to escape the symbolism of the "circle" in prehistoric cosmologies, and the pre-eminence of the circle in Greek astronomical thought is obvious. Is the "circular" ikon of the main wheel in Antikythera Mechanism simply another gear wheel, or might ideas of cosmology have influenced its design? How important would devices like the Antikythera Mechanism have been in providing a physical model of the Universe , pushing mathematical abstraction into reality? The relevance of the Mechanism is understanding the development of ideas and philosophy, particularly determinism is emphasized.
Protocol for Isolating the Mouse Circle of Willis.
Hur, Justine Claire; Blaise, Régis; Limon, Isabelle
2016-10-22
The cerebral arterial circle (circulus arteriosus cerebri) or circle of Willis (CoW) is a circulatory anastomosis surrounding the optic chiasma and hypothalamus that supplies blood to the brain and surrounding structures. It has been implicated in several cerebrovascular disorders, including cerebral amyloid angiopathy (CAA)-associated vasculopathies, intracranial atherosclerosis and intracranial aneurysms. Studies of the molecular mechanisms underlying these diseases for the identification of novel drug targets for their prevention require animal models. Some of these models may be transgenic, whereas others will involve isolation of the cerebro-vasculature, including the CoW.The method described here is suitable for CoW isolation in any mouse lineage and has considerable potential for screening (expression of genes, protein production, posttranslational protein modifications, secretome analysis, etc.) studies on the large vessels of the mouse cerebro-vasculature. It can also be used for ex vivo studies, by adapting the organ bath system developed for isolated mouse olfactory arteries.
Culture Circles in adolescent empowerment for the prevention of violence.
Monteiro, Estela Maria Leite Meirelles; Neto, Waldemar Brandão; de Lima, Luciane Soares; de Aquino, Jael Maria; Gontijo, Daniela Tavares; Pereira, Beatriz Oliveira
2015-04-03
An action research based on Paulo Freire's Culture Circles was developed to implement a health education intervention involving adolescents, in collective knowledge construction about strategies for the prevention of violence. The data collection in the Culture Circles involved 11 adolescents and included observation and field diary, photographic records and recording. The educational action aroused a critical socio-political and cultural position in the adolescents towards the situations of vulnerability to violence, including the guarantee of human rights, justice and the combat of inequities; changes in the social relations, combat against discrimination and intolerance; expansion of access and reorientation of health services through intersectoral public policies. The intervention empowered the group of adolescents for the prevention of violence and permitted the inclusion of health professionals in the school context, from an interdisciplinary perspective, contributing to the establishment of social support and protection networks.
Rolling circle amplification of complete nematode mitochondrial genomes.
Tang, Sha; Hyman, Bradley C
2005-06-01
To enable investigation of nematode mitochondrial DNA evolution, methodology has been developed to amplify intact nematode mitochondrial genomes in preparative yields using a rolling circle replication strategy. Successful reactions were generated from whole cell template DNA prepared by alkaline lysis of the rhabditid nematode Caenorhabditis elegans and a mermithid nematode, Thaumamermis cosgrovei. These taxa, representing the two major nematode classes Chromodorea and Enoplea, maintain mitochondrial genomes of 13.8 kb and 20.0 kb, respectively. Efficient amplifications were conducted on template DNA isolated from individual or pooled nematodes that were alive or stored at -80 degrees C. Unexpectedly, these experiments revealed that multiple T. cosgrovei mitochondrial DNA haplotypes are maintained in our local population. Rolling circle amplification products can be used as templates for standard PCR reactions with specific primers that target mitochondrial genes or for direct DNA sequencing.
The concept of magic circle: a critical reading
Directory of Open Access Journals (Sweden)
Arlete dos Santos Petry
2013-09-01
Full Text Available This article deals with establishing and discussing the concept of magic circle - often present in game studies - and ponder the possible relations with the concept of liminality, worked in cultural anthropology from the rites of passage standpoint in Van Gennep and Victor Turner and with the concept of transitional phenomenon by psychoanalyst Donald Winnicott. Towards that, we seek references in studies of the respective areas of knowledge, in order to reflect on the experience of play. The establishment of the relationship between the concepts mentioned - magic circle, liminality, transitional phenomenon - takes a step forward on the path that seeks to answer what play is and its relevance in contemporary life. Thus, given the large access to digital games today, this article provides a relevant contribution to Communication studies.
About Nodal Systems for Lagrange Interpolation on the Circle
Directory of Open Access Journals (Sweden)
E. Berriochoa
2012-01-01
Full Text Available We study the convergence of the Laurent polynomials of Lagrange interpolation on the unit circle for continuous functions satisfying a condition about their modulus of continuity. The novelty of the result is that now the nodal systems are more general than those constituted by the n roots of complex unimodular numbers and the class of functions is different from the usually studied. Moreover, some consequences for the Lagrange interpolation on [-1,1] and the Lagrange trigonometric interpolation are obtained.
The Quality Circles Organizational Intervention: An Attitudinal Outcome Study
1983-09-01
communication between themselves and their employees "(Dickson, 1982). Victor Vroom has developed a "normative model" of par- ticipative decision...SECUMIYY CLASSIOPI CAr? MO h LSSR 19-83 THE QUALITY CIRCLES ORGANIZATIONAL INTERVENTION: AN ATTITUDINAL OUTCOME STUDY A Thesis Presented ýo the...democratic style, and a set of seven rules intended to pro- tect both the quality and acceptance of a leader’s decision. -26 Vroom provides a decision
Content-aware photo collage using circle packing.
Yu, Zongqiao; Lu, Lin; Guo, Yanwen; Fan, Rongfei; Liu, Mingming; Wang, Wenping
2014-02-01
In this paper, we present a novel approach for automatically creating the photo collage that assembles the interest regions of a given group of images naturally. Previous methods on photo collage are generally built upon a well-defined optimization framework, which computes all the geometric parameters and layer indices for input photos on the given canvas by optimizing a unified objective function. The complex nonlinear form of optimization function limits their scalability and efficiency. From the geometric point of view, we recast the generation of collage as a region partition problem such that each image is displayed in its corresponding region partitioned from the canvas. The core of this is an efficient power-diagram-based circle packing algorithm that arranges a series of circles assigned to input photos compactly in the given canvas. To favor important photos, the circles are associated with image importances determined by an image ranking process. A heuristic search process is developed to ensure that salient information of each photo is displayed in the polygonal area resulting from circle packing. With our new formulation, each factor influencing the state of a photo is optimized in an independent stage, and computation of the optimal states for neighboring photos are completely decoupled. This improves the scalability of collage results and ensures their diversity. We also devise a saliency-based image fusion scheme to generate seamless compositive collage. Our approach can generate the collages on nonrectangular canvases and supports interactive collage that allows the user to refine collage results according to his/her personal preferences. We conduct extensive experiments and show the superiority of our algorithm by comparing against previous methods.
Uncertainty budget for optical coordinate measurements of circle diameter
DEFF Research Database (Denmark)
Morace, Renate Erica; Hansen, Hans Nørgaard; De Chiffre, Leonardo
2004-01-01
An uncertainty analysis for circle diameter measurements using a coordinate measuring machine (CMM) equipped with an optical probe is presented in this paper. A mathematical model for data evaluation and uncertainty assessment was formulated in accordance with Guide to the Expression of Uncertainty...... in Measurement (GUM). Various input quantities such as CCD camera resolution, influence of illuminating system, CMM errors etc. were considered in the model function and experimentally investigated....
BANQUET SPEECH Full Circle: Star Ferry to Stardust
Matthews, Clifford N.
2008-10-01
Good evening. I'd like to invite you to join me on a journey that could be entitled “Full Circle: Star Ferry to Stardust”. “Star Ferry” represents Hong Kong, my home town, and especially its university - Hong Kong University - as I knew it during the years of World War II. “Stardust” refers to our gathering here to report on our research on possible organic chemistry in space.
Quality Circles: An Innovative Program to Improve Military Hospitals
1982-08-01
effective teamwork, (3) promote job involvemenL, (4) increase employee motivation , (5) create a problem-solving capability, (6) build an attitude of...from greater employee motivation and involve- ment in work. Quality Circles (Q.C.’s) are small groups of volunteers from the same work area who meet on...effectiveness Measurable feedback Key people and team members in same area for better personnel management Greater productivity Employee motivation Effective use
Largest Empty Circle Centered on a Query Line
Augustine, John; Roy, Sasanka
2008-01-01
The Largest Empty Circle problem seeks the largest circle centered within the convex hull of a set $P$ of $n$ points in $\\mathbb{R}^2$ and devoid of points from $P$. In this paper, we introduce a query version of this well-studied problem. In our query version, we are required to preprocess $P$ so that when given a query line $Q$, we can quickly compute the largest empty circle centered at some point on $Q$ and within the convex hull of $P$. We present solutions for two special cases and the general case; all our queries run in $O(\\log n)$ time. We restrict the query line to be horizontal in the first special case, which we preprocess in $O(n \\alpha(n) \\log n)$ time and space, where $\\alpha(n)$ is the slow growing inverse of the Ackermann's function. When the query line is restricted to pass through a fixed point, the second special case, our preprocessing takes $O(n \\alpha(n)^{O(\\alpha(n))} \\log n)$ time and space. We use insights from the two special cases to solve the general version of the problem with pr...
Volume calculation of the spur gear billet for cold precision forging with average circle method
Institute of Scientific and Technical Information of China (English)
Wangjun Cheng; Chengzhong Chi; Yongzhen Wang; Peng Lin; Wei Liang; Chen Li
2014-01-01
Forging spur gears are widely used in the driving system of mining machinery and equipment due to their higher strength and dimensional accuracy. For the purpose of precisely calculating the volume of cylindrical spur gear billet in cold precision forging, a new theoretical method named average circle method was put forward. With this method, a series of gear billet volumes were calculated. Comparing with the accurate three-dimensional modeling method, the accuracy of average circle method by theoretical calculation was estimated and the maximum relative error of average circle method was less than 1.5%, which was in good agreement with the experimental results. Relative errors of the calculated and the experimental for obtaining the gear billet volumes with reference circle method are larger than those of the average circle method. It shows that average circle method possesses a higher calculation accuracy than reference circle method (traditional method), which should be worth popularizing widely in calculation of spur gear billet volume.
Voice of the voiceless: The legacy of the Circle of Concerned African Women Theologians
Directory of Open Access Journals (Sweden)
Hazel O. Ayanga
2016-07-01
Full Text Available The Circle of Concerned African Women Theologians (the Circle formally came into existence in 1989 in Accra, Ghana. Under the charismatic leadership of Mercy Amba Oduyoye, the Circle sought to be the voice of African Christian women at the grass roots level. To this end research and publication was and still is one of the major pillars and activities of the Circle. The main objective of the Circle is �to write and publish theological literature written by African women from their own experience of religion and culture on this continent�. In this regard the Circle has been and continues to be the voice for and on behalf of the African woman in religion, culture and theology. However, 25 years down the line there is need for an evaluation of the legacy of the Circle. How has the Circle been a voice for the voiceless, a mentoring instrument for women venturing into the academia? This article seeks to do this evaluation by examining the activities of the Circle including research publication.Intradisciplinary and/or interdisciplinary implications: This article seeks to evaluate the achievements of the Circle of Concerned African Women Theologians in relation to the Circle�s stated objectives. The article picks up the notion of the Circle theologians as the voice of the voiceless women of Africa. The general approach of the article brings together discussions on social issues like gender, poverty and marginalisation as well as language. Theological and religious perspectives on these issues are understood from a Circle point of view.Keywords: women; voice; voicelessness; poverty; gender; The Circle; theology
Stereoscopic Machine-Vision System Using Projected Circles
Mackey, Jeffrey R.
2010-01-01
A machine-vision system capable of detecting obstacles large enough to damage or trap a robotic vehicle is undergoing development. The system includes (1) a pattern generator that projects concentric circles of laser light forward onto the terrain, (2) a stereoscopic pair of cameras that are aimed forward to acquire images of the circles, (3) a frame grabber and digitizer for acquiring image data from the cameras, and (4) a single-board computer that processes the data. The system is being developed as a prototype of machine- vision systems to enable robotic vehicles ( rovers ) on remote planets to avoid craters, large rocks, and other terrain features that could capture or damage the vehicles. Potential terrestrial applications of systems like this one could include terrain mapping, collision avoidance, navigation of robotic vehicles, mining, and robotic rescue. This system is based partly on the same principles as those of a prior stereoscopic machine-vision system in which the cameras acquire images of a single stripe of laser light that is swept forward across the terrain. However, this system is designed to afford improvements over some of the undesirable features of the prior system, including the need for a pan-and-tilt mechanism to aim the laser to generate the swept stripe, ambiguities in interpretation of the single-stripe image, the time needed to sweep the stripe across the terrain and process the data from many images acquired during that time, and difficulty of calibration because of the narrowness of the stripe. In this system, the pattern generator does not contain any moving parts and need not be mounted on a pan-and-tilt mechanism: the pattern of concentric circles is projected steadily in the forward direction. The system calibrates itself by use of data acquired during projection of the concentric-circle pattern onto a known target representing flat ground. The calibration- target image data are stored in the computer memory for use as a
Deteksi Iris Berdasarkan Metode Black Hole dan Circle Curve Fitting
Directory of Open Access Journals (Sweden)
Danny Kurnianto
2013-11-01
Full Text Available Sistem pengenalan identitas personal berdasarkan ciri biometrika adalah suatu sistem pengenalan seseorang berdasarkan pada ciri biometrika yang melekat pada orang tersebut. Iris mata merupakan salah satu ciri biometrik yang handal untuk sistem pengenalan identitas personal. Bagian sistem pengenalan identitas personal berdasarkan biometrik iris yang dianggap paling krusial adalah deteksi lokasi iris, karena akurasi deteksi iris berpengaruh pada tingkat akurasi sistem secara keseluruhan. Lokasi iris pada citra mata dibatasi oleh dua buah lingkaran yang memisahkan antara bagian iris dengan pupil dan sklera. Telah banyak metodemetode yang diusulkan oleh para peneliti untuk menghasilkan deteksi lokasi iris dengan akurat dan cepat. Masalah akurasi, kecepatan waktu eksekusi dan ketahanan terhadap noise merupakan bidang penelitian yang menantang pada deteksi iris. Makalah ini menyajikan metode deteksi iris menggunakan metode black hole dan circle curve fitting. Langkah pertama, mencari batas dalam lingkaran iris yang memisahkan antara daerah iris dan pupil. Dengan metode black hole yang bekerja berdasarkan fakta bahwa lokasi pupil merupakan daerah lingkaran yang paling hitam dan memiliki distribusi nilai intensitas yang seragam, maka lokasi pupil dapat ditentukan dengan teknik pengambangan. Batas lingkaran pupil dapat ditentukan dengan circle curve fitting dari parameter lingkaran daerah pupil. Langkah kedua, mencari batas luar lingkaran iris yang memisahkan antara iris dan sklera. Peta tepi citra iris dicari dengan menggunakan deteksi tepi Canny, kemudian diambil satu komponen tepi arah vertikal yang dapat mewakili batas lingkaran luar iris. Dari komponen tepi tersebut, dihitung jari-jari iris yang berpusat di pusat pupil. Dengan jari-jari iris dan pusat iris maka dapat ditentukan batas luar iris menggunakan circle curve fitting
The Risks We Dread: A Social Circle Account
Galesic, Mirta; Garcia-Retamero, Rocio
2012-01-01
What makes some risks dreadful? We propose that people are particularly sensitive to threats that could kill the number of people that is similar to the size of a typical human social circle. Although there is some variability in reported sizes of social circles, active contact rarely seems to be maintained with more than about 100 people. The loss of this immediate social group may have had survival consequences in the past and still causes great distress to people today. Therefore we hypothesize that risks that threaten a much larger number of people (e.g., 1000) will not be dreaded more than those that threaten to kill “only” the number of people typical for social circles. We found support for this hypothesis in 9 experiments using different risk scenarios, measurements of fear, and samples from different countries. Fear of risks killing 100 people was higher than fear of risks killing 10 people, but there was no difference in fear of risks killing 100 or 1000 people (Experiments 1–4, 7–9). Also in support of the hypothesis, the median number of deaths that would cause maximum level of fear was 100 (Experiments 5 and 6). These results are not a consequence of lack of differentiation between the numbers 100 and 1000 (Experiments 7 and 8), and are different from the phenomenon of “psychophysical numbing” that occurs in the context of altruistic behavior towards members of other communities rather than in the context of threat to one's own community (Experiment 9). We discuss several possible explanations of these findings. Our results stress the importance of considering social environments when studying people's understanding of and reactions to risks. PMID:22509250
The dot-in-circle sign of mycetoma on MRI.
Kumar, Jyoti; Kumar, Atin; Sethy, Pradeep; Gupta, Somesh
2007-12-01
Mycetoma is a chronic granulomatous disease prevalent in tropical countries, but it also occurs in Europe and the United States. Early diagnosis is important as it has therapeutic implications. Although biopsy and microbiological culture provide the definitive diagnosis, these are difficult to achieve in many instances. The dot-in-circle sign is a recently proposed magnetic resonance imaging (MRI) sign of mycetoma, which is likely to be highly specific. We present a case of mycetoma of the thigh with characteristic MRI features. To the best of our knowledge, only 2 cases of mycetoma of the foot demonstrating this sign have been previously published.
The Phenomenological Circle and the Unity of Life and Thought.
Atwood, George E; Stolorow, Robert D
2016-06-01
This paper describes the important role of our deep immersions in philosophy in the development of our phenomenological-contextualist approach to psychoanalysis. Influenced most particularly by the phenomenological movement, our collaborative dialogue over more than four decades has led us to a shared commitment to reflection upon the philosophical underpinnings and constitutive contexts of origin of all our theoretical ideas. The growth of our thinking follows an endlessly recurring phenomenological circle joining theoretical perspectives with the inquirers from whose emotional worlds they arise.
Star Formation Beyond the Solar Circle: A Survey of Surveys
Kerton, Charles R.
2013-06-01
This talk will review and distill the results of major radio, infrared, and combined radio/IR, surveys that have focused on the identification and characterization of active regions of star formation in the outer Galaxy. These surveys reveal that, in terms of star formation activity, the Milky Way beyond the solar circle is not a vast wasteland, but rather it is an area containing numerous regions of star formation well placed for detailed individual study, for large-scale studies of star formation within spiral arms, and for comparative studies with star formation occurring in different environments such as the inner Galaxy and Galactic center.
[Albert Fromme (1881-1996) and his circle].
Klimpel, V
1996-12-01
Among Saxony's schools of surgery, Albert Fromme's in Dresden attain importance. On the basis of his work as a university professor in Göttingen for 10 years, he was able to train a large circle of surgeons in a major hospital. However, this did not detract from his clinical and scientific work. A. Fromme reached the top of German surgery and his crowning achievement was gaining the full professorship and rectorship of the Medical Academy "Carl Gustav Carus" in Dresden (today the Medical Faculty of the Technical University.
SPECTRA OF MOTHERS OF PREMATURE CHILDREN ABOUT THE EDUCATIVE CIRCLE OF CULTURE
Directory of Open Access Journals (Sweden)
Camila Santos do Couto
2014-12-01
Full Text Available Abstract We sought to know the spectra of mothers of premature children regarding their experience with circle of culture of educational character and identifying the learning provided by the circle of culture about newborn care after hospital discharge. A descriptive study was performed in a hospital located in Fortaleza, Brazil. Three meetings of a circle of culture with 17 mothers of premature newborns were performed. The interpretation of the corpus was performed using thematic analysis. Emerged from the categories: Maternal experience in a circle of culture; Promoted social support among mothers through the circle of culture; and Learning provided by the circle of culture. It was concluded that teaching parents during the hospitalization of the child should be held in a way to involve parents in the care of the newborn, provide moments of health education, opportunities for support and dialogue between professionals and family.
Eccentricity on AN Image Caused by Projection of a Circle and a Sphere
Matsuoka, R.; Maruyama, S.
2016-06-01
Circular targets on a plane are often utilized in photogrammetry, particularly in close range photogrammetry, while spherical targets are sometimes utilized in industrial applications. Both a circle and a sphere are projected as an ellipse onto an image. There is an eccentricity on an image between the centre of the projected ellipse and the projected location of the centre of a circle or a sphere. Since only the centre of the projected ellipse is measured, the correction of the eccentricity is considered to be necessary for highly accurate measurement. This paper shows a process to derive general formulae to calculate an eccentricity of a circle and a sphere using the size and the location of a circle or a sphere, and the focal length, the position and the attitude of a camera. Furthermore the paper shows methods to estimate the eccentricity of a circle and a sphere from the equation of the projected ellipse of a circle or a sphere on an image.
Drawing Euler Diagrams with Circles: The Theory of Piercings.
Stapleton, Gem; Leishi Zhang; Howse, John; Rodgers, Peter
2011-07-01
Euler diagrams are effective tools for visualizing set intersections. They have a large number of application areas ranging from statistical data analysis to software engineering. However, the automated generation of Euler diagrams has never been easy: given an abstract description of a required Euler diagram, it is computationally expensive to generate the diagram. Moreover, the generated diagrams represent sets by polygons, sometimes with quite irregular shapes that make the diagrams less comprehensible. In this paper, we address these two issues by developing the theory of piercings, where we define single piercing curves and double piercing curves. We prove that if a diagram can be built inductively by successively adding piercing curves under certain constraints, then it can be drawn with circles, which are more esthetically pleasing than arbitrary polygons. The theory of piercings is developed at the abstract level. In addition, we present a Java implementation that, given an inductively pierced abstract description, generates an Euler diagram consisting only of circles within polynomial time.
Strange Non-Chaotic Attractors in Quasiperiodically Forced Circle Maps
Jäger, Tobias
2009-07-01
The occurrence of strange non-chaotic attractors (SNA) in quasiperiodically forced systems has attracted considerable interest over the last two decades, in particular since it provides a rich class of examples for the possibility of complicated dynamics in the absence of chaos. Their existence was first described by Millions̆c̆ikov (and later by Vinograd and also Herman) for quasiperiodic {SL(2, {mathbb R})} -cocycles and by Grebogi et al (and later Keller) for so-called pinched skew products. However, except for these two particular classes there are still hardly any rigorous results on the topic, despite a large number of numerical studies confirming the widespread existence of SNA in quasiperiodically forced systems. Here, we prove the existence of SNA in quasiperiodically forced circle maps under rather general conditions, which can be stated in terms of {{mathcal C}^1} -estimates. As a consequence, we obtain the existence of SNA for parameter sets of positive measure in suitable parameter families. These SNA carry the unique physical measure of the system, which determines the behaviour of Lebesgue-almost all initial conditions. Finally, we show that the dynamics are minimal in the considered situations. The results apply in particular to a forced version of the Arnold circle map. For this example, we also describe how the first Arnold tongue collapses and looses its regularity due to the presence of strange non-chaotic attractors and a related unbounded mean motion property.
Beyond paradigms in Organization Studies: the Circle of Epistemic Matrices
Directory of Open Access Journals (Sweden)
Ana Paula Paes de Paula
Full Text Available Abstract In this article, I present a sketch of a new proposition to guide organizational studies: the Cicle of Epistemic Matrices. Inspired by Thomas Kuhn and based on the thesis of paradigms' incommensurability, Gibson Burrell and Gareth Morgan drew the diagram of sociological paradigms, but its inclusion in the academy has encouraged a paradigms war. The Circle of Epistemic Matrices also provides an outline for the guidance of organizational studies, but it is based on Habermas and defends the thesis of cognitive incompleteness, suggesting that the sociological and organizational knowledge grows according to the thesis of epistemic reconstructions. To accomplish these propositions and elaborations, I present the debate about the paradigms' war in literature and I question the adequacy of sociological paradigms of Gibson Burrell and Gareth Morgan to organizational studies, with the issue of the influence that it suffered from Kuhnian paradigms and logic. In the following sections, there is an exhibition of alternative proposition - the of Circle of Epistemic Matrices - and, also, I support the thesis of cognitive incompleteness and the thesis of epistemic reconstructions in order to bring a new theory of knowledge development to the area. Finally, I present the findings and thoughts for future research.
Eva Malatinkova; Maja Kiselinova; Pawel Bonczkowski; Wim Trypsteen; Peter Messiaen; Jolien Vermeire; Bruno Verhasselt; Karen Vervisch; Linos Vandekerckhove; Ward De Spiegelaere
2014-01-01
Introduction: In HIV-infected patients on combination antiretroviral therapy (cART), the detection of episomal HIV 2-LTR circles is a potential marker for ongoing viral replication. Quantification of 2-LTR circles is based on quantitative PCR or more recently on digital PCR assessment, but is hampered due to its low abundance. Sample pre-PCR processing is a critical step for 2-LTR circles quantification, which has not yet been sufficiently evaluated in patient derived samples. Materials and M...
Squaring the Project Management Circle: Updating the Cost, Schedule, and Performance Methodology
2016-04-30
measure execution. This paper suggests that the cost, schedule, and performance paradigm, while still effective as a measure of managing programs, needs...acquisition and its relationship to the measures of cost, schedule, and performance—the project management circle (see Figure 1). Rather than use the... management circle. The circle recognizes the interrelationships, necessary equilibrium, and the influencing and balancing effects that these three
Tallink Spa Hotell : Sadama 11, Tallinn / Liina Jänes
Jänes, Liina, 1977-
2008-01-01
Arhitektid: Ülar Mark, Indrek Tiigi. Sisekujundus: Andro Kööp, Tairo Pärnamets. Skulptuurid: Hannes Starkopf, Aime Kuulbusch. Žürii liikme Mari Kurismaa arvamus. Joon.: peafassaad, 2 värv. välis- ja 3 sisevaadet
Freifelder, D; Folkmanis, A; Kirschner, I
1971-03-01
We examined in detail conditions necessary for making reproducible and for maximizing the amount of deoxyribonucleic acid obtained from a sex factor-containing cell as covalent circles. The results argue that under optimal conditions covalent circles are neither created nor lost during the isolation procedure. The causes of the culture-to-culture variation in recovery of covalent circular deoxyribonucleic acid were investigated but an understanding of this is not yet at hand. Some commonly used conditions which drastically reduce the recovery of covalent circles are described.
The interpersonal circle as a heuristic model for interpersonal research.
Lorr, M
1996-04-01
In this article, I review major advances in the development of the interpersonal circle and its measurement, as delineated by Timothy Leafy (1957) and his colleagues. In my early work (Lorr & McNair, 1963, 1965), an interpersonal Behavior Inventory consisting of manifest behavioral statements was constructed. The 14 categories were found to fit a circular order in several samples. Studies using LaForge and Suczek's (1955) Interpersonal Check List, and Wiggins's (1979) Interpersonal Adjective Scales further established the value of Leary's conceptions and extended them. Several major theorists, researchers, and clinicians including Benjamin, Carson, Horowitz, Kiesler, and Wiggins have been inspired by Leary and, in many cases, have extended his ideas in ways not originally envisioned. Recent research (e.g., Hofstee, de Raad, & Goldberg, 1992; Millon, 1987) demonstrated the pertinence of the interpersonal conception of personality to the 5-factor model and personality disorders.
Minimalisasi Kekurangan Material Melalui Implementasi Quality Control Circle
Directory of Open Access Journals (Sweden)
Togar W. S. Panjaitan
2011-01-01
Full Text Available The revolution of traditional quality management concept into total quality management (TQM inspired industry for establishing and implementing quality control circle (QCC. Before starting a project as the implementation of the QCC, the training was held for supporting the knowledge of the QCC team. As the pilot project of the QCC, this research will try to minimize the percentage of the lack material in the production process of 8340 type by working together with the QCC team. The result of QCC implementation could reach the target set by the team, the percentage of the lack material reached less than 3%. The percentage of the lack material kontaktarm reduced from 3.09% to 0.00%, flachdrahtspule reduced from 9.20% to 0.40%, and niet reduced from 7.71% to 2.73%. Besides, the implementation of QCC also resulted in positive impact for all the members of the team about the benefits and experiences gained.
Two personification strategies for solving circles packing problem
Institute of Scientific and Technical Information of China (English)
黄文奇[1; 许如初[2
1999-01-01
Two personification strategies are presented, which yield a highly efficient and practical algorithm for solving one of the NP hard problems——circles packing problem on the basis of the quasi-physical algorithm. A very clever polynomial time complexity degree approximate algorithm for solving this problem has been reported by Dorit S.Hochbaum and Wolfgang Maass in J. ACM. Their algorithm is extremely thorough-going and of great theoretical significance. But, just as they pointed out, their algorithm is feasible only in conception and even for examples frequently encountered in everyday life and of small scale, it is the case more often than not that up to a million years would be needed to perform calculations with this algorithm. It is suggested toward the end of their paper that a heuristic algorithm of higher practical effectiveness should be sought out. A direct response to their suggestion is intented to provide.
Application of digital holography to circle flow bed boiler measurement
Institute of Scientific and Technical Information of China (English)
PU Shiliang; Denis Lebrun; WANG Qinghui; CEN Kefa; REN Kuanfang
2007-01-01
The spatial distribution of particles in the boiler is very important in the study on the circle flow bed boiler (CFB). Digital in-line holography technique was applied to obtain the spatial and diameter distribution of the particles inside the boiler. A HE-NE laser was used to illuminate the particles inside the CFB through two glass windows and the in-line diffraction pattern was recorded by a CCD camera. The diffraction can be interpreted as a convolution between a family of wavelet functions and the object function. So the three-dimensional (3D) images of the particles in the two-phase flow were reconstructed by the convolution between diffraction pattern and wavelet functions. The particle diameters and 3D coordinates were calculated from the reconstructed 3D images by a series of image-processing methods, followed by a discussion of the experimental results.
Planar maps, circle patterns and 2d gravity
David, Francois
2013-01-01
Via circle pattern techniques, random planar triangulations (with angle variables) are mapped onto Delaunay triangulations in the complex plane. The uniform measure on triangulations is mapped onto a conformally invariant spatial point process. We show that this measure can be expressed as: (1) a sum over 3-spanning-trees partitions of the edges of the Delaunay triangulations; (2) the volume form of a K\\"ahler metric over the space of Delaunay triangulations, whose prepotential has a simple formulation in term of ideal tessellations of the 3d hyperbolic space; (3) a discretized version (involving finite difference complex derivative operators) of Polyakov's conformal Fadeev-Popov determinant in 2d gravity; (4) a combination of Chern classes, thus also establishing a link with topological 2d gravity.
Circle Hough transform implementation for dots recognition in braille cells
Jacinto Gómez, Edwar; Montiel Ariza, Holman; Martínez Sarmiento, Fredy Hernán.
2017-02-01
This paper shows a technique based on CHT (Circle Hough Transform) to achieve the optical Braille recognition (OBR). Unlike other papers developed around the same topic, this one is made by using Hough Transform to process the recognition and transcription of Braille cells, proving CHT to be an appropriate technique to go over different non-systematics factors who can affect the process, as the paper type where the text to traduce is placed, some lightning factors, input image resolution and some flaws derived from the capture process, which is realized using a scanner. Tests are performed with a local database using text generated by visual nondisabled people and some transcripts by sightless people; all of this with the support of National Institute for Blind People (INCI for their Spanish acronym) placed in Colombia.
Camera calibration approach using circle-square-combined target
Institute of Scientific and Technical Information of China (English)
Fuqiang Zhou; Yexin Wang; Yi Cui; Haishu Tan
2012-01-01
Calibrating a small field camera is a challenging task because the traditional target with visible feature points that fit the limited space is difficult and costly to manufacture. We demonstrate a novel combined target used in camera calibration. The tangent points supplied by one circle located at the center of a square are used as invisible features, and the perspective projection invariance is proved. Both visible and invisible features extracted by the proposed feature extraction algorithm are used to solve the calibration. The target supplies a sufficient number of feature points to satisfy the requirements of calibration within a limited space. Experiments show that the approach can achieve high robustness and considerable accuracy. This approach has potential for computer vision applications particularly in small fields of view.%Calibrating a small field camera is a challenging task because the traditional target with visible feature points that fit the limited space is difficult and costly to manufacture.We demonstrate a novel combined target used in camera calibration.The tangent points supplied by one circle located at the center of a square are used as invisible features,and the perspective projection invariance is proved.Both visible and invisible features extracted by the proposed feature extraction algorithm are used to solve the calibration.The target supplies a sufficient number of feature points to satisfy the requirements of calibration within a limited space.Experiments show that the approach can achieve high robustness and considerable accuracy.This approach has potential for computer vision applications particularly in small fields of view.
Dynamic Investigation of Triangles Inscribed in a Circle, Which Tend to an Equilateral Triangle
Stupel, Moshe; Oxman, Victor; Sigler, Avi
2017-01-01
We present a geometrical investigation of the process of creating an infinite sequence of triangles inscribed in a circle, whose areas, perimeters and lengths of radii of the inscribed circles tend to a limit in a monotonous manner. First, using geometrical software, we investigate four theorems that represent interesting geometrical properties,…
Comparing Interactions in Literature Circles in Both Online and in Class Discussions
Skeen, Christel Ghrist
2014-01-01
Discourse analysis of literature circles can lead educators to understand the different types of interactions taking place as students talk about text. Social and academic interactions exist in both face-to-face and online discussions of reading material. This study examines two different settings of literature circles and compares interactions of…
Circle Time: An Exploratory Study of Activities and Challenging Behavior in Head Start Classrooms
Zaghlawan, Hasan Y.; Ostrosky, Michaelene M.
2011-01-01
The purpose of this descriptive study was to examine circle time activities in eight Head Start classrooms. A total of 7 h of observations occurred in eight classrooms. Songs and academic activities were the most frequently occurring activities. Challenging behavior during circle time also was examined. The three activities with the highest…
The Revival of Research Circles: Meeting the Needs of Modern Aging and the Third Age
Ostlund, Britt
2008-01-01
This article provides evidence that it is worthwhile to reconsider the traditional research circle method as a means of involving people in the third age in fulfilling their needs to participate in learning activities and make their voices heard. The findings are based on three cases of research circles consistently driven by the interests of the…
Migraine without aura is not associated with incomplete circle of Willis
DEFF Research Database (Denmark)
Ezzatian-Ahar, Shabnam; Amin, Faisal Mohammad; Obaid, Hayder Ghani
2014-01-01
the prevalence of incomplete circle of Willis in migraineurs and controls. In the present study we compared the prevalence of incomplete circle of Willis in female migraine patients without aura to female healthy non-migraine controls.Using 3-Tesla magnetic resonance angiography we recorded three...
A surface containing a line and a circle through each point is a quadric
Nilov, Fedor K.
2012-06-20
We prove that a surface in 3-dimensional Euclidean space containing a line and a circle through each point is a quadric. We also give some particular results on the classification of surfaces containing several circles through each point. © 2012 Springer Science+Business Media B.V.
Metaxas, Nikolaos; Karagiannidou, Andromachi
2010-01-01
Visualization of mathematical relationships enables students to formulate conjectures as well as to search for mathematical arguments to support these conjectures. In this project students are asked to discover the sufficient and necessary condition so that two circles form the circumscribed and inscribed circle of a triangle and investigate how…
Non-positively curved graph manifolds are virtually fibered over the circle
2001-01-01
In this note we prove that any closed graph manifold admitting a metric of non-positive sectional curvature (NPC-metric) has a finite cover, which is fibered over the circle. An explicit criterion to have a finite cover, which is fibered over the circle, is presented for the graph manifolds of certain class.
Sufficient Conditions for Dynamical Output Feedback Stabilization Via the Circle Criterion
2003-01-01
This paper suggests sufficient conditions for asymptotically stable dynamical output feedback controller design based on the circle criterion. It is shown that a dynamic output feedback stabilization problem with impending problems of finite escape time, previously attacked by observer-based design, can be successfully solved using circle criterion design. Stability of the closed-loop system is global and robust to parameter uncertainty.
Schwarz’s lemma for the circle packings with the general combinatorics
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
Rodin (1987) proved the Schwarz’s lemma analog for the circle packings based on the hexagonal combinatorics. In this paper, we prove the Schwarz’s lemma for the circle packings with the general combinatorics and our proof is more simpler than Rodin’s proof. At the same time, we obtain a rigidity property for those packings with the general combinatorics.
Bernadowski, Carianne
2013-01-01
Literature circles and book clubs have become a popular instructional literacy strategy. In recent years, educators attempt to motivate students to read more in quantity and quality at an early age. A case study design was utilized that required undergraduate education majors to participate in literature circles reading historical fiction and…
Laying the Groundwork for the Effective Implementation of Quality Circles in a Community College.
Ruff, Dan
This five-part paper provides an overview of the use of quality circles as a participative management technique in community colleges. Section I offers an introduction to the technique, reviewing the history of quality circles from their development in Japan in the early 1960s to their introduction in American higher education in the early 1980s.…
Rudd, Rima; Soricone, Lisa; Santos, Maricel; Zobel, Emily; Smith, Janet
2005-01-01
A Health Literacy Study Circle[superscript +] is a multi-session professional development activity for adult education practitioners, conducted by a facilitator. All the information and materials required to conduct each Health Literacy Study Circle[superscript +] is presented in two parts: this Introduction and the "Facilitator's Guide" for each…
A new method for fast circle detection in a complex background image
Wu, Meijun; Yang, Jie; Sun, Yadong
2011-11-01
A new method for circle detection, Hough gradient clustering method, has been developed in this paper. By using gradient direction angle to find the diameter of a circle, the new method can rapidly detect the circle in a complex background. The crucial steps in this method are the feature extraction and the clustering of the points which have the same gray direction angle and are collinear along the gradient direction. The application of the two-to-one space mapping and 1-2Hough transform can further reduce the useless calculation in the process of circle detection. Comparing with the Hough gradient method in OpenCV, the newly developed method shows a higher efficiency of circle detection in a complex background image as well as a great improvement in the anti-noise ability.
Closed circle DNA algorithm of change positive-weighted Hamilton circuit problem
Institute of Scientific and Technical Information of China (English)
Zhou Kang; Tong Xiaojun; Xu Jin
2009-01-01
Chain length of closed circle DNA is equal. The same closed circle DNA's position corresponds to different recognition sequence, and the same recognition sequence corresponds to different foreign DNA segment, so closed circle DNA computing model is generalized. For change positive-weighted Hamilton circuit problem, closed circle DNA algorithm is put forward. First, three groups of DNA encoding are encoded for all arcs, and deck groups are designed for all vertices. All possible solutions axe composed. Then, the feasible solutions axe filtered out by using group detect experiment, and the optimization solutions are obtained by using group insert experiment and electrophoresis experiment. Finally, all optimization solutions are found by using detect experiment. Complexity of algorithm is concluded and validity of DNA algorithm is explained by an example. Three dominances of the closed circle DNA algorithm are analyzed, and characteristics and dominances of group delete experiment axe discussed.
The role of Circle women in curbing violence against women and girls in Africa
Directory of Open Access Journals (Sweden)
Sylvia Owusu-Ansah
2016-07-01
Full Text Available The article looks at the role Circle of Concerned African Women Theologians (the Circle have played in the struggle to end or reduce the rate at which violence against women and girls occurs in West Africa by highlighting the contributions of older Circle women, especially the initiator of the Circle, Mercy Amba Oduyoye. The initiator of the Circle and other older Circle women have left a remarkable legacy that needs to continue by the current and future generations of the Circle. The background information examines the leadership and mentorship of Mercy Amba Oduyoye and the impact she has made in the lives of African women. The essay then looks at the types of violence that women face in West Africa with the specific contributions of Circle women in the struggle to end violence against women and girls. It then argues that Circle women have played very significant roles both in setting the pace and giving the platform for women activities to minimise gender-based violence against women and girls. Circle women have written and presented papers that have addressed many challenges including HIV and/or AIDS, Girl Child trafficking, Marriage of Minors, and almost all kinds of violence against women and girls. Currently, religious violence threatens the fabric of African nations causing insecurity and panic, women and girls being the most vulnerable. The challenge to the present and future Circle members is to contribute in significant ways towards religious harmony in Africa and beyond. The Circle acknowledges the leadership role of women and encourages them to spearhead the liberation of women as well as empower them to be able to aspire to get to the top or become independent. No one understands what someone else feels better than the person experiencing the ordeal. Women can better understand what they go through and also have the passion to strive towards liberation.Intradisciplinary and/or interdisciplinary implications: In this article, the
Kinetics of the forelimb in horses circling on different ground surfaces at the trot.
Chateau, Henry; Camus, Mathieu; Holden-Douilly, Laurène; Falala, Sylvain; Ravary, Bérangère; Vergari, Claudio; Lepley, Justine; Denoix, Jean-Marie; Pourcelot, Philippe; Crevier-Denoix, Nathalie
2013-12-01
Circling increases the expression of distal forelimb lameness in the horse, depending on rein, diameter and surface properties of the circle. However, there is limited information about the kinetics of horses trotting on circles. The aim of this study was to quantify ground reaction force (GRF) and moments in the inside and outside forelimb of horses trotting on circles and to compare the results obtained on different ground surfaces. The right front hoof of six horses was equipped with a dynamometric horseshoe, allowing the measurement of 3-dimensional GRF, moments and trajectory of the centre of pressure. The horses were lunged at slow trot (3 m/s) on right and left 4 m radius circles on asphalt and on a fibre sand surface. During circling, the inside forelimb produced a smaller peak vertical force and the stance phase was longer in comparison with the outside forelimb. Both right and left circling produced a substantial transversal force directed outwards. On a soft surface (sand fibre), the peak transversal force and moments around the longitudinal and vertical axes of the hoof were significantly decreased in comparison with a hard surface (asphalt). Sinking of the lateral or medial part of the hoof in a more compliant surface enables reallocation of part of the transversal force into a proximo-distal force, aligned with the limb axis, thus limiting extrasagittal stress on the joints.
Surface kinematics of periglacial sorted circles using Structure-from-Motion technology
Directory of Open Access Journals (Sweden)
A. Kääb
2013-12-01
Full Text Available Sorted soil circles are a conspicuous form of periglacial patterned ground. Numerical modelling suggests that these features develop from a convection-like circulation of material in the active layer of permafrost. The related iterative burying and resurfacing of material is believed to play an important role in the soil carbon cycle of high latitudes. The connection of sorted circles to permafrost conditions and its changes over time make these ground forms to a potential paleoclimatic indicator. In this study we apply the photogrammetric Structure-from-Motion technology (SfM to large sets of overlapping terrestrial photos taken in Augusts 2007 and 2010 over three sorted circles at Kvadehuksletta, Western Spitsbergen. We retrieve repeat digital elevation models (DEMs and orthoimages with millimetre-resolution and accuracy. Changes in microrelief over the three years are obtained from DEM-differencing and horizontal displacement fields from tracking features between the orthoimages. In the inner domains of the circles, consisting of fines, material moves radially outside with horizontal surface speeds of up to 2 cm yr−1. The outer circle ridges consist of coarse stones that displace towards the inner circle domain at similar rates. A number of substantial deviations from this overall radial symmetry, both in horizontal displacements and in microrelief, shed new light on the potential spatio-temporal evolution of sorted soil circles, and periglacial patterned ground in general.
Modelling of the toe trajectory during normal gait using circle-fit approximation.
Fang, Juan; Hunt, Kenneth J; Xie, Le; Yang, Guo-Yuan
2016-10-01
This work aimed to validate the approach of using a circle to fit the toe trajectory relative to the hip and to investigate linear regression models for describing such toe trajectories from normal gait. Twenty-four subjects walked at seven speeds. Best-fit circle algorithms were developed to approximate the relative toe trajectory using a circle. It was detected that the mean approximation error between the toe trajectory and its best-fit circle was less than 4 %. Regarding the best-fit circles for the toe trajectories from all subjects, the normalised radius was constant, while the normalised centre offset reduced when the walking cadence increased; the curve range generally had a positive linear relationship with the walking cadence. The regression functions of the circle radius, the centre offset and the curve range with leg length and walking cadence were definitively defined. This study demonstrated that circle-fit approximation of the relative toe trajectories is generally applicable in normal gait. The functions provided a quantitative description of the relative toe trajectories. These results have potential application for design of gait rehabilitation technologies.
Vienna Circle and Logical Analysis of Relativity Theory
Andréka, H; Németi, I; Németi, P; Székely, G
2011-01-01
In this paper we present some of our school's results in the area of building up relativity theory (RT) as a hierarchy of theories in the sense of logic. We use plain first-order logic (FOL) as in the foundation of mathematics (FOM) and we build on experience gained in FOM. The main aims of our school are the following: We want to base the theory on simple, unambiguous axioms with clear meanings. It should be absolutely understandable for any reader what the axioms say and the reader can decide about each axiom whether he likes it. The theory should be built up from these axioms in a straightforward, logical manner. We want to provide an analysis of the logical structure of the theory. We investigate which axioms are needed for which predictions of RT. We want to make RT more transparent logically, easier to understand, easier to change, modular, and easier to teach. We want to obtain deeper understanding of RT. Our work can be considered as a case-study showing that the Vienna Circle's (VC) approach to doing...
Using great circles to understand motion on a rotating sphere
McIntyre, D. H.
2000-12-01
Motion observed in a rotating frame of reference is generally explained by invoking inertial forces. While this approach simplifies some problems, there is often little physical insight into the motion, in particular into the effects of the Coriolis force. To aid in the understanding of three-dimensional inertial forces, motion on a rotating sphere is considered from the points of view of an inertial observer and of an observer fixed on the sphere. The inertial observer observes the motion to be along a great circle fixed in the inertial frame, in analogy with simple straight-line motion in the two-dimensional case. This simple "straight-line" viewpoint of the inertial observer is reconciled qualitatively and quantitatively with the view of the rotating observer that requires inertial forces in order to account for the motion. Through a succession of simple examples, the Coriolis and centrifugal effects are isolated and illustrated, as well as effects due to the curvilinear nature of motion on a sphere.
Taking a literature circles approach to teach Academic English
Directory of Open Access Journals (Sweden)
Graham-Marr Alastair
2016-01-01
Full Text Available Literature circles (LC, an activity framework for classroom discussion, has been adapted for EFL classes to help students engage more deeply with reading texts. In this approach, students read texts outside of class, and discuss the texts in class, using a specified discussion framework. Originally developed for L1 classes as a tool for teaching literature, LC has been adapted for EFL classes, not only to help develop reading skills, but also to help students develop their discussion skills. However, to date, many adaptations of LC have relied on graded fiction as source material, which is not always appropriate for tertiary education. Feeling pressure to match course content with the labour market needs of our contemporary global society, English departments are increasingly being asked to include more academic content in their classes. This requires that non-fiction be used as source material. This preliminary study examines student perceptions of an LC class using non-fiction as source material. The subjects of this short, qualitative, pilot study were engineering students at a university in Japan. Procedures of the class and the issues that emerged are discussed.
Is "circling" behavior in humans related to postural asymmetry?
Directory of Open Access Journals (Sweden)
Emma Bestaven
Full Text Available In attempting to walk rectilinearly in the absence of visual landmarks, persons will gradually turn in a circle to eventually become lost. The aim of the present study was to provide insights into the possible underlying mechanisms of this behavior. For each subject (N = 15 six trajectories were monitored during blindfolded walking in a large enclosed area to suppress external cues, and ground irregularities that may elicit unexpected changes in direction. There was a substantial variability from trial to trial for a given subject and between subjects who could either veer very early or relatively late. Of the total number of trials, 50% trajectories terminated on the left side, 39% on the right side and 11% were defined as "straight". For each subject, we established a "turning score" that reflected his/her preferential side of veering. The turning score was found to be unrelated to any evident biomechanical asymmetry or functional dominance (eye, hand.... Posturographic analysis, used to assess if there was a relationship between functional postural asymmetry and veering revealed that the mean position of the center of foot pressure during balance tests was correlated with the turning score. Finally, we established that the mean position of the center of pressure was correlated with perceived verticality assessed by a subjective verticality test. Together, our results suggest that veering is related to a "sense of straight ahead" that could be shaped by vestibular inputs.
End of the line to build a circle
2006-01-01
The installation of the cryogenic distribution line in the LHC tunnel is finally finished! All the sectors have undergone pressure and helium leak tests at room temperature, and one complete sector was cold tested in cryogenic conditions. Some of the QRL team in UJ22 of the LHC tunnel, where the last sector of the cryogenic distribution line was installed.It must have been a joyous moment in UJ22 of the LHC tunnel (near Point 2, Saint Genis Pouilly) on 19 October. This was where the last external weld of the cryogenic distribution line, also known as QRL, was made, thus completing the full distribution ring. The QRL is a circle built in 8 sectors, each approximately 3 km in length. It will circulate helium in liquid and gas phases, at different temperatures and pressures, to provide the cryogenic conditions for the superconducting magnets in the LHC tunnel. The last sector installed (sector 1-2) passed the pressure and helium leak tests at room temperature on 28 October. As part of the warm test, each sector...
Institute of Scientific and Technical Information of China (English)
雷友诚; 涂祖耀; 桂卫华; 吴志飞; 闫福全
2011-01-01
Aiming at the distribution of railway line and a combinatorial mode of placing-in and taking-out wagons at an enterprise railway freight station, a mathematical model of optimal operation for placing-in and taking-out wagons in the branch-shaped private line was established, which is deduced as a typical traveling salesman problem(TSP). Meanwhile, a combination of genetic algorithm and ant colony algorithm called GACA was presented to resolve the large-scale combinatorial optimization problem. The genetic algorithm was adopted to generate pheromone to distribute. And the ant colony algorithm was used to find an accurate solution. As a result, the searching efficiency and the time efficiency of the combinatorial algorithm are both greatly improved. Combined with an example, the optimal solution of the placing-in and taking-out wagons problem is found.%针对企业铁路货运站的铁路线分布特点和“连送带取”的作业方式,建立树枝型专用线取送车的数学模型,将其归纳为一个典型的旅行商问题.同时提出一种融合遗传算法和蚁群算法特点的遗传蚁群算法(GACA)来解决这种大规模组合优化问题；采用遗传算法生成信息素分布,利用蚁群算法求精确解,有效提高算法的时间效率和求解效率.结合实例计算求得了企业取送车作业问题的最优解.
Topography of arterial circle of the brain in Egyptian spiny mouse (Acomys cahirinus, Desmarest).
Szczurkowski, A; Kuchinka, J; Nowak, E; Kuder, T
2007-04-01
Using stained acryl latex-injected techniques, the arterial circle of the brain in Acomys cahirinus Desmarest was studied. Results revealed an important individual variability of investigated structure. Three morphological variants were found: (1) the lack of typical arterial circle--opened in front and the back side, (2) partial opened at the back side, (3) completely closed arterial circle. This finding is opposed to many species of mammals, including rodents, and especially laboratory mouse. In our point of view, it seems to be a specific character.
Altman, Renana; Kidron, Ivy
2016-10-01
Processes of knowledge construction are investigated. A learner is constructing knowledge about the trigonometric functions and their geometric meaning on the unit circle. The analysis is based on the dynamically nested epistemic action model for abstraction in context. Different tasks are offered to the learner. In his effort to perform the different tasks, he has the opportunity to understand the process used to create unit circle representations of trigonometric expressions. The theoretical framework of abstraction in context is used to analyse the evolution of the learner's construction of knowledge in the transition from 'triangle' trigonometry to 'circle' trigonometry.
Wang, Haoxu; Dong, Peitao; Xie, Liqiang; Wu, Xuezhong
2014-03-01
The vibration characteristic analysis method for a quartz microgyroscope based on the admittance circle is reported in this paper. Admittance theory is introduced and the admittance circle principle is analysed to study the vibration characteristics of the quartz microgyroscope. The prototype gyroscope was fabricated by micro-electromechanical systems (MEMS) technology. The admittance and phase diagram of the work mode were obtained by vibration mode test systems. Then the admittance circle of the work mode was drawn, and the parameter identification of the transfer function between the voltage and current was completed to analyse the vibration characteristics. Therefore, the vibration characteristic analysis method based on the admittance circle can be used to build the transfer function of the quartz microgyroscope, which is helpful for the design of a high performance quartz microgyroscope.
Directory of Open Access Journals (Sweden)
Haoxu Wang
2014-02-01
Full Text Available The vibration characteristic analysis method for a quartz microgyroscope based on the admittance circle is reported in this paper. Admittance theory is introduced and the admittance circle principle is analysed to study the vibration characteristics of the quartz microgyroscope. The prototype gyroscope was fabricated by micro-electromechanical systems (MEMS technology. The admittance and phase diagram of the work mode were obtained by vibration mode test systems. Then the admittance circle of the work mode was drawn, and the parameter identification of the transfer function between the voltage and current was completed to analyse the vibration characteristics. Therefore, the vibration characteristic analysis method based on the admittance circle can be used to build the transfer function of the quartz microgyroscope, which is helpful for the design of a high performance quartz microgyroscope.
College geometry an introduction to the modern geometry of the triangle and the circle
Altshiller-Court, Nathan
2007-01-01
The standard university-level text for decades, this volume offers exercises in construction problems, harmonic division, circle and triangle geometry, and other areas. 1952 edition, revised and enlarged by the author.
Approximating the Euclidean circle in the square grid using neighbourhood sequences
Farkas, Janos; Nagy, Benedek
2010-01-01
Distance measuring is a very important task in digital geometry and digital image processing. Due to our natural approach to geometry we think of the set of points that are equally far from a given point as a Euclidean circle. Using the classical neighbourhood relations on digital grids, we get circles that greatly differ from the Euclidean circle. In this paper we examine different methods of approximating the Euclidean circle in the square grid, considering the possible motivations as well. We compare the perimeter-, area-, curve- and noncompactness-based approximations and examine their realization using neighbourhood sequences. We also provide a table which summarizes our results, and can be used when developing applications that support neighbourhood sequences.
Geologic Provinces of the Circum-Arctic, 2008 (north of the Arctic Circle)
U.S. Geological Survey, Department of the Interior — This shapefile includes arcs and polygons that describe U.S. Geological Survey defined 33 geologic provinces of the Circum-Arctic (north of the Arctic Circle). Each...
Endonuclease-rolling circle amplification-based method for sensitive analysis of DNA-binding protein
Institute of Scientific and Technical Information of China (English)
Min Li Li; Dong Rui Zhou; Hong Zhao; Jin Ke Wang; Zu Hong Lu
2009-01-01
A sensitive approach for the qualitative detection of DNA-binding protein on the microarray was developed. DNA complexes in which a partial duplex region is formed from a biotin-primer and a circle single strand DNA (ssDNA) were spotted on a microarray. The endonuclease recognition site (ERS) and the DNA-binding sites (DBS) were arranged side by side within the duplex region. The working principle of the detection system is described as follows: when the DNA-binding protein capture the DBS, the endonuclease could not attach to the ERS, and the immobilized primer in the DNA complex could be extended along the circle ssDNA by rolling circle amplification (RCA). When no protein protects the DBS, the ERS could be attacked by the endonuclease and subsequently no rolling circle amplification occurs. Thereby we can detect the sequence specific DNA-binding activity with high-sensitivity due to the signal amplification of RCA.
Circle drawing as evaluative movement task in stroke rehabilitation: an explorative study
Directory of Open Access Journals (Sweden)
Rietman Johan S
2011-03-01
Full Text Available Abstract Background The majority of stroke survivors have to cope with deficits in arm function, which is often measured with subjective clinical scales. The objective of this study is to examine whether circle drawing metrics are suitable objective outcome measures for measuring upper extremity function of stroke survivors. Methods Stroke survivors (n = 16 and healthy subjects (n = 20 drew circles, as big and as round as possible, above a table top. Joint angles and positions were measured. Circle area and roundness were calculated, and synergistic movement patterns were identified based on simultaneous changes of the elevation angle and elbow angle. Results Stroke survivors had statistically significant lower values for circle area, roundness and joint excursions, compared to healthy subjects. Stroke survivors moved significantly more within synergistic movement patterns, compared to healthy subjects. Strong correlations between the proximal upper extremity part of the Fugl-Meyer scale and circle area, roundness, joint excursions and the use of synergistic movement patterns were found. Conclusions The present study showed statistically significant differences in circle area, roundness and the use of synergistic movement patterns between healthy subjects and stroke survivors. These circle metrics are strongly correlated to stroke severity, as indicated by the proximal upper extremity part of the FM score. In clinical practice, circle area and roundness can give useful objective information regarding arm function of stroke survivors. In a research setting, outcome measures addressing the occurrence of synergistic movement patterns can help to increase understanding of mechanisms involved in restoration of post stroke upper extremity function.
A robust circle criterion observer with application to neural mass models
2012-01-01
International audience; A robust circle criterion observer is designed and applied to neural mass models. At present, no existing circle criterion observers apply to the considered models, i.e. the required linear matrix inequality is infeasible. Therefore, we generalise available results to derive a suitable estimation algorithm. Additionally, the design also takes into account input uncertainty and measurement noise. We show how to apply the observer to estimate the mean membrane potential ...
Twistor quantization of the space of half-differentiable vector functions on the circle revisited
Institute of Scientific and Technical Information of China (English)
SERGEEV; Armen
2009-01-01
We discuss the twistor quantization problem for the classical system(Vd,Ad),represented by the phase space Vd,identified with the Sobolev space H 1/2 0 (S1,Rd)of half-differentiable vector functions on the circle,and the algebra of observables Ad,identified with the semi-direct product of the Heisenberg algebra of Vd and the algebra Vect(S1)of tangent vector fields on the circle.
Occlusion of the circle of Willis. Diagnosis by 3D-time of flight MR angiography
Energy Technology Data Exchange (ETDEWEB)
Komatsumoto, Satoru; Ushioda, Takakazu; Nara, Masaharu [Ashikaga Red Cross Hospital, Tochigi (Japan)
1996-08-01
Magnetic resonance angiograms (MRA) were studied in 7 cases of occlusion of the circle of Willis. MRA successfully demonstrated the vascular obstructions and moyamoya vessels with a positive correlation to the angiographic findings. Leptomeningeal and transdural collateral vessels were also identified with MRA. As MRA is not invasive, it promises to become a valuable alternature to conventional angiography in the diagnosis of occlusion of the circle of Willis. (author)
Directory of Open Access Journals (Sweden)
Menno C. Van Zelm
2011-05-01
Full Text Available The vast majority of patients suffering from a primary immunodeficiency (PID have defects in their T- and/or B-cell compartments. Despite advances in molecular diagnostics, in many patients no underlying genetic defect has been identified. B- and T-lymphocytes are unique in their ability to create a receptor by genomic rearrangement of their antigen receptor genes via V(DJ recombination. During this process, stable circular excision products are formed that do not replicate when the cell proliferates. Excision circles can be reliably quantified using real-time quantitative (RQ-PCR techniques. Frequently occurring δREC–ψJα T-cell receptor excision circles (TRECs have been used to assess thymic output and intronRSS–Kde recombination excision circles (KREC to quantify B-cell replication history. In this perspective, we describe how TRECs and KRECs are formed during precursor- T and B cell differentiation, respectively. Furthermore, we discuss new insights obtained with TRECs and KRECs and specifically how these excision circles can be applied to support therapy monitoring, patient classification and newborn screening of PID.
Introspection, empathy, and the semi-circle of mental health.
Kohut, H
1982-01-01
Written shortly before his death, Heinz Kohut's last paper opens with a discussion of the paper 'Introspection, empathy, and psychoanalysis', written in 1959, which he presented at the Twenty-fifth Anniversary Meeting of the Chicago Institute for Psychoanalysis. In his first essay on the role of empathy in psychoanalysis, an essay that according to Kohut provided a foundation for many of his subsequent investigations in the field of depth psychology, he advanced the thesis that the introspective-empathic stance of the observer defines the science of psychoanalysis. The author explains that he was moved to propose this operational definition of psychoanalysis twenty-five years before because he felt that the introduction of the psychobiological concept of the drives (as well as various social psychological concepts) had not led to a true integration of psychoanalysis with biology or medicine but to a psychological and moral view of 'Guilty Man' that worked to distort the analyst's perception in the clinical and applied field. Kohut asserts that by defining itself operationally, psychoanalysis can accept itself as psychology, a psychology that studies man in terms of a self attempting to realize the programme laid down in his depth during the span of his life. The final section of the paper is devoted to a re-examination of man's intergenerational relationships in light of the shift Kohut advocates from psychobiology to psychology. The Oedipus complex is not to be understood as the end product of the uninfluentiable conflict of basic opposing instincts but as the result of interferences that impinge on man's development. Acknowledging the mythic power of Freud's formulation of the Oedipus complex, the author offers a dose of mythical counter-magic (to which the 'semi-circle of mental health' in the paper's title refers) and a re-interpretation of the story of King Oedipus. Kohut believes that the essence of human experience is not to be found in the biologically
Anatomical variations of the circle of Willis and cerebrovascular accidents in transitional Albania
Directory of Open Access Journals (Sweden)
Edlira Harizi (Shemsi
2015-12-01
Full Text Available Aim: The purpose of this study was twofold: i in a case-control design, to determine the relationship between anatomical variations of the circle of Willis and cerebrovascular accidents; ii to assess the association between anatomical variations of the circle of Willis and aneurisms among patients with subarachnoid hemorrhage. Methods: A case-control study was conducted in Albania in 2013-2014, including 100 patients with subarachnoid hemorrhage and 100 controls (individuals without cerebrovascular accidents. Patients with subarachnoid hemorrhage underwent a CT angiography procedure, whereas individuals in the control group underwent a magnetic resonance angiography procedure. Binary logistic regression was used to assess the association between cerebrovascular accidents and the anatomical variations of the circle of Willis. Conversely, Fisher’s exact test was used to compare the prevalence of aneurisms between subarachnoid hemorrhage patients with and without anatomical variations of the circle of Willis. Results: Among patients, there were 22 (22% cases with anatomical variations of the circle of Willis compared with 10 (10% individuals in the control group (P=0.033. There was no evidence of a statistically significant difference in the types of the anatomical variations of the circle of Willis between patients and controls (P=0.402. In age- and-sex adjusted logistic regression models, there was evidence of a significant positive association between cerebrovascular accidents and the anatomical variations of the circle of Willis (OR=1.87, 95%CI=1.03-4.68, P=0.048. Within the patients’ group, of the 52 cases with aneurisms, there were 22 (42.3% individuals with anatomical variations of the circle of Willis compared with no individuals with anatomical variations among the 48 patients without aneurisms (P<0.001. Conclusion: This study provides useful evidence on the association between anatomical variations of the circle of Willis and
Anatomical Variations of the Circle of Willis in Males and Females on 3D MR Angiograms
Directory of Open Access Journals (Sweden)
Kawther A. Hafez, Nahla M. Afifi, Fardous Z. Saudi
2007-03-01
Full Text Available Objective: The objective of the present work was to study the anatomical variations of the circle of Willis as regard its component vessels and their average diameters in a sample of adult Egyptians and to detect any sex-related differences in these variations. Material and Methods: One hundred and twenty adult patients were observed (60 males and 60 females. They all had problems unrelated to any ischemic or vascular diseases, so they were considered as healthy control, concerning the morphology of the circle of Willis. In addition, ten cadavers' brains were obtained from the Anatomy department, Faculty of Medicine Ain Shams University for examination of the circle of Willis and for detection of any variations. Results: The anatomical variations of the anterior part, posterior part and completeness of the circle were inspected. Also, the diameters of all component vessels were assessed. The results indicated that, the anterior part of the circle was completed in 70% males and 75% females of the study sample. No statistically significant difference was detected between sexes. The most common variant of the anterior part was the single anterior communicating artery followed by the hypoplastic or absent anterior communicating artery. The posterior part of the circle was completed in 44% males and 58% females. The most common variant was the bilateral posterior communicating arteries, followed by the unilateral posterior communicating artery. An entirely complete circle was found only in 45% of the entire population; and it was higher in the females than the in males. The vessels diameters were smaller in the females than in the males, except for the diameter of the posterior communicating artery. Cadavers' examination revealed six cases with complete circle, 3 cases of unilateral fetal posterior communicating and one case of absent posterior communicating artery. Conclusion: The present study showed the amazing great variability of the anatomy of
Directory of Open Access Journals (Sweden)
Bishwajeet Saikia
2014-06-01
Full Text Available Background: The circle of Willis is a large arterial anastomotic ring present at the base of the brain uniting the internal carotid and the vertebrobasilar systems. Branches from the internal carotid and vertebral arteries anastomose to form an arterial circle in the basal cisterns and then distribute to supply the brain. The anatomy of the circle is known to vary significantly; the vessels may be absent or sufficiently narrowed altering the hemodynamics of the circle of Willis and affecting its role as a collateral route. These variant forms can be correlated to their phylogeny and embryology. Prior knowledge of these variant forms is important in pathologies and treatment (e.g. parent artery occlusion for carotid aneurysms resulting occlusion of carotid and vertebral arteries. Context and purpose: Our study was undertaken to observe and compare the morphology of circle of Willis using two entirely different methods; gross dissection (GD and Magnetic resonance angiography (MRA and to correlate the variant patterns encountered with the possible underlying developmental events. Gross dissection was carried out in 70 human cadavers and equal numbers of MRA’s of healthy individuals were studied retrospectively. Results: Only 31 cases (22.14% presented with a complete circle of Willis, out of which 14 (20% were cadaveric specimen and 17 (24.18% were in MRA group. Unilateral hypoplastic posterior communicating artery was the most common variation observed in our study (19.28%. Conclusions: The wide variation in completeness of the circle of Willis in general population is similar to earlier observations. Review of phylogeny and embryology makes us familiar with variant forms which would be otherwise difficult to recognize and may be misinterpreted. MRA and gross dissection findings despite certain variations are comparable.
Directory of Open Access Journals (Sweden)
Eva Malatinkova
2014-11-01
Full Text Available Introduction: In HIV-infected patients on combination antiretroviral therapy (cART, the detection of episomal HIV 2-LTR circles is a potential marker for ongoing viral replication. Quantification of 2-LTR circles is based on quantitative PCR or more recently on digital PCR assessment, but is hampered due to its low abundance. Sample pre-PCR processing is a critical step for 2-LTR circles quantification, which has not yet been sufficiently evaluated in patient derived samples. Materials and Methods: We compared two sample processing procedures to more accurately quantify 2-LTR circles using droplet digital PCR (ddPCR. Episomal HIV 2-LTR circles were either isolated by genomic DNA isolation or by a modified plasmid DNA isolation, to separate the small episomal circular DNA from chromosomal DNA. This was performed in a dilution series of HIV-infected cells and HIV-1 infected patient derived samples (n=59. Samples for the plasmid DNA isolation method were spiked with an internal control plasmid. Results: Genomic DNA isolation enables robust 2-LTR circles quantification. However, in the lower ranges of detection, PCR inhibition caused by high genomic DNA load substantially limits the amount of sample input and this impacts sensitivity and accuracy. Moreover, total genomic DNA isolation resulted in a lower recovery of 2-LTR templates per isolate, further reducing its sensitivity. The modified plasmid DNA isolation with a spiked reference for normalization was more accurate in these low ranges compared to genomic DNA isolation. A linear correlation of both methods was observed in the dilution series (R2=0.974 and in the patient derived samples with 2-LTR numbers above 10 copies per million peripheral blood mononuclear cells (PBMCs, (R2=0.671. Furthermore, Bland–Altman analysis revealed an average agreement between the methods within the 27 samples in which 2-LTR circles were detectable with both methods (bias: 0.3875±1.2657 log10. Conclusions: 2-LTR
Calculation of the mean circle size does not circumvent the bottleneck of crowding.
Banno, Hayaki; Saiki, Jun
2012-10-22
Visually, we can extract a statistical summary of sets of elements efficiently. However, our visual system has a severe limitation in that the ability to recognize an object is remarkably impaired when it is surrounded by other objects. The goal of this study was to investigate whether the crowding effect obstructs the calculation of the mean size of objects. First, we verified that the crowding effect occurs when comparing the sizes of circles (Experiment 1). Next, we manipulated the distances between circles and measured the sensitivity when circles were on or off the limitation of crowding (Experiment 2). Participants were asked to compare the mean sizes of the circles in the left and right visual fields and to judge which was larger. Participants' sensitivity to mean size difference was lower when the circles were located in the nearer distance. Finally, we confirmed that crowding is responsible for the observed results by showing that displays without a crowded object eliminated the effects (Experiment 3). Our results indicate that the statistical information of size does not circumvent the bottleneck of crowding.
Does the Value Circle Exist Within Persons or Only Across Persons?
Borg, Ingwer; Bardi, Anat; Schwartz, Shalom H
2017-04-01
This study tests whether the Schwartz (1992) value circle exists within individuals, not only across individuals, thereby providing evidence for the within-person rationale underlying the value circle. We analyze responses from five samples (a representative sample in Britain, a general population sample in the United States, and university students in Britain and Iran) varying in value measures of the Schwartz value theory (SVS, PVQ40, PVQ21). An unfolding model is used to map each person's value profile into a two-dimensional space representing both persons and values. In all samples, clear value circles were found, with values ordered around the circle largely according to the theory. The model also represents most individuals well. The value circle exists within individuals, providing strong support for the underlying within-person rationale for the Schwartz (1992) value theory. The unfolding analysis allows identifying which persons fit the model less well and in which way, identifying how meaningful subgroups differ in their value profiles, and testing whether meaningful subgroups have different value structures. The model opens up many new possibilities for research linking values to other variables.
Directory of Open Access Journals (Sweden)
Yazan M. Alomari
2014-01-01
Full Text Available Segmentation and counting of blood cells are considered as an important step that helps to extract features to diagnose some specific diseases like malaria or leukemia. The manual counting of white blood cells (WBCs and red blood cells (RBCs in microscopic images is an extremely tedious, time consuming, and inaccurate process. Automatic analysis will allow hematologist experts to perform faster and more accurately. The proposed method uses an iterative structured circle detection algorithm for the segmentation and counting of WBCs and RBCs. The separation of WBCs from RBCs was achieved by thresholding, and specific preprocessing steps were developed for each cell type. Counting was performed for each image using the proposed method based on modified circle detection, which automatically counted the cells. Several modifications were made to the basic (RCD algorithm to solve the initialization problem, detecting irregular circles (cells, selecting the optimal circle from the candidate circles, determining the number of iterations in a fully dynamic way to enhance algorithm detection, and running time. The validation method used to determine segmentation accuracy was a quantitative analysis that included Precision, Recall, and F-measurement tests. The average accuracy of the proposed method was 95.3% for RBCs and 98.4% for WBCs.
Infraorbital dark circles: A review of the pathogenesis, evaluation and treatment
Directory of Open Access Journals (Sweden)
Ivan Vrcek
2016-01-01
Full Text Available Infraorbital dark circles represent a common and multifactorial challenge in the world of aesthetic medicine and are the result of a variety of factors including deep facial anatomy, soft tissue changes, as well as contributions from the skin. A variety of treatment options exist, and a customised management strategy can be developed for the particular anatomic changes present. A literature search using MEDLINE and non-MEDLINE sources was performed utilising keywords including: 'Dark circles' 'infraorbital dark circles', 'infraorbital pigment', 'under-eye circles' and 'lower eyelid bags'. A comprehensive review of the literature was performed and the data were assimilated with evidence from our practice. This review provides a detailed discussion of the aetiology, pathogenesis, evaluation and management of infraorbital dark circles. An understanding of the deep and superficial anatomy is crucial to the management of this complex entity. The armamentarium for treatment includes minimally invasive interventions such as makeup and cosmeceuticals, a variety of laser and chemical treatments, fillers and fat transfer, as well as more invasive surgical manoeuvres.
Ansari, Saeed; Dadmehr, Majid; Eftekhar, Behzad; McConnell, Douglas J; Ganji, Sarah; Azari, Hassan; Kamali-Ardakani, Shahab; Hoh, Brian L; Mocco, J
2011-12-01
This article describes a straightforward method to measure the dimensions and identify morphological variations in the cerebral arterial circle using the general-purpose software program Osiris. This user-friendly and portable program displays, manipulates, and analyzes medical digital images, and it has the capability to determine morphometric properties of selected blood vessels (or other anatomical structures) in humans and animals. To ascertain morphometric variations in the cerebral arterial circle, 132 brains of recently deceased fetuses, infants, and adults were dissected. The dissection procedure was first digitized, and then the dimensions were measured with Osiris software. Measurements of each vessel's length and external diameters were used to identify and classify morphological variations in the cerebral arterial circle. The most commonly observed anatomical variations were uni- and bilateral hypoplasia of the posterior communicating artery. This study demonstrates that public domain software can be used to measure and classify cerebral arterial circle vessels. This method could be extended to examine other anatomical regions or to study other animals. Additionally, knowledge of variations within the circle could be applied clinically to enhance diagnostic and treatment specificity.
Matsui, Mary S; Schalka, Sérgio; Vanderover, Garrett; Fthenakis, Christina G.; Christopher, J; Bombarda, Patricia Camarano Pinto; Bueno, Juliana Regina; Viscomi, Bianca Lenci Inácio; Bombarda Júnior, Mário Sérgio
2015-01-01
BACKGROUND Peri-orbital dark circles are a cosmetic concern worldwide, and have been attributed to hyperpigmentation from allergy or atopic dermatitis, blood stasis, structural shadowing effects, and a thin epidermis/dermis under the eye. It is of interest to better understand lifestyle and demographic risk factors and the relative impact of melanin, blood and epidermal/dermal factors on the severity of Peri-orbital dark circles. OBJECTIVE To compare by non-invasive imaging the impact of biological factors to a visual grading scale for Peri-orbital dark circles, and test the correlation of various demographic factors with Peri-orbital dark circles. METHODS Subjects completed a lifestyle and health survey, and Peri-orbital dark circles severity was evaluated using standardized photographs. Hyperspectral image analysis was used to assess the contributions of melanin, blood volume, degree of blood oxygen saturation, and dermal scattering. RESULTS Family history was the most significant risk factor for Peri-orbital dark circles. The average age of onset was 24 years, and earlier onset correlated with higher severity scores. Asthma was significantly associated with Peri-orbital dark circles scores, but self-reported allergy was not. In this study, sleep was not correlated with Peri-orbital dark circles scores. Hyperspectral imaging indicated that melanin was the dominant correlate for Peri-orbital dark circles severity, while oxygen saturation was secondary. The difference between under-eye and cheek measurements for ∆L*and ∆E* were the most significant instrumental parameters correlated with visual assessment of Peri-orbital dark circles severity. CONCLUSION Although typically associated with lack of sleep, risk of Peri-orbital dark circles is primarily hereditary. The main factors contributing to the appearance of Peri-orbital dark circles are melanin and (deoxygenated) blood. PMID:26375218
An algorithm for Path planning with polygon obstacles avoidance based on the virtual circle tangents
Directory of Open Access Journals (Sweden)
Zahraa Y. Ibrahim
2016-12-01
Full Text Available In this paper, a new algorithm called the virtual circle tangents is introduced for mobile robot navigation in an environment with polygonal shape obstacles. The algorithm relies on representing the polygonal shape obstacles by virtual circles, and then all the possible trajectories from source to target is constructed by computing the visible tangents between the robot and the virtual circle obstacles. A new method for searching the shortest path from source to target is suggested. Two states of the simulation are suggested, the first one is the off-line state and the other is the on-line state. The introduced method is compared with two other algorithms to study its performance.
Librino, Federico; Zorzi, Michele
2012-01-01
A novel iterative algorithm for the efficient computation of the intersection areas of an arbitrary number of circles is presented. The algorithm, based on a trellis-structure, hinges on two geometric results which allow the existence-check and the computation of the area of the intersection regions generated by more than three circles by simple algebraic manipulations of the intersection areas of a smaller number of circles. The presented algorithm is a powerful tool for the performance analysis of wireless networks, and finds many applications, ranging from sensor to cellular networks. As an example of practical application, an insightful study of the uplink outage probability of in a wireless network with cooperative access points as a function of the transmission power and access point density is presented.
On the sum of powered distances to certain sets of points on the circle
Nikolov, Nikolai
2011-01-01
In this paper we consider an extremal problem in geometry. Let $\\lambda$ be a real number and $A$, $B$ and $C$ be arbitrary points on the unit circle $\\Gamma$. We give full characterization of the extremal behavior of the function $f(M,\\lambda)=MA^\\lambda+MB^\\lambda+MC^\\lambda$, where $M$ is a point on the unit circle as well. We also investigate the extremal behavior of $\\sum_{i=1}^nXP_i$, where $P_i, i=1,...,n$ are the vertices of a regular $n$-gon and $X$ is a point on $\\Gamma$, concentric to the circle circumscribed around $P_1...P_n$. We use elementary analytic and purely geometric methods in the proof.
Directory of Open Access Journals (Sweden)
Washington Alves de Oliveira
Full Text Available ABSTRACT In this work we propose a heuristic algorithm for the layout optimization for disks installed in a rotating circular container. This is a unequal circle packing problem with additional balance constraints. It proved to be an NP-hard problem, which justifies heuristics methods for its resolution in larger instances. The main feature of our heuristic is based on the selection of the next circle to be placed inside the container according to the position of the system's center of mass. Our approach has been tested on a series of instances up to 55 circles and compared with the literature. Computational results show good performance in terms of solution quality and computational time for the proposed algorithm.
Great circle solution to polarization-based quantum communication (QC) in optical fiber
Nordholt, Jane Elizabeth; Peterson, Charles Glen; Newell, Raymond Thorson; Hughes, Richard John
2016-03-15
Birefringence in optical fibers is compensated by applying polarization modulation at a receiver. Polarization modulation is applied so that a transmitted optical signal has states of polarization (SOPs) that are equally spaced on the Poincare sphere. Fiber birefringence encountered in propagation between a transmitter and a receiver rotates the great circle on the Poincare sphere that represents the polarization bases used for modulation. By adjusting received polarizations, polarization components of the received optical signal can be directed to corresponding detectors for decoding, regardless of the magnitude and orientation of the fiber birefringence. A transmitter can be configured to transmit in conjugate polarization bases whose SOPs can be represented as equidistant points on a great circle so that the received SOPs are mapped to equidistant points on a great circle and routed to corresponding detectors.
Mosh pits and Circle pits: Collective motion at heavy metal concerts
Bierbaum, Matthew; Silverberg, Jesse L.; Sethna, James P.; Cohen, Itai
2013-03-01
Heavy metal concerts present an extreme environment in which large crowds (~102 -105) of humans experience very loud music (~ 130 dB) in sync with bright, flashing lights, often while intoxicated. In this setting, we find two types of collective motion: mosh pits, in which participants collide with each other randomly in a manner resembling an ideal gas, and circle pits, in which participants run collectively in a circle forming a vortex of people. We model these two collective behaviors using a flocking model and find qualitative and quantitative agreement with the behaviors found in videos of metal concerts. Futhermore, we find a phase diagram showing the transition from a mosh pit to a circle pit as well as a predicted third phase, lane formation.
Alvarez-Fernandez, Carlos
2012-01-01
Orthogonal Laurent polynomials in the unit circle and the theory of Toda-like integrable systems are connected using the Gauss--Borel factorization of a Cantero-Moral-Velazquez moment matrix, which is constructed in terms of a complex quasi-definite measure supported in the unit circle. The factorization of the moment matrix leads to orthogonal Laurent polynomials in the unit circle and the corresponding second kind functions. Jacobi operators, 5-term recursion relations and Christoffel-Darboux kernels, projecting to particular spaces of truncated Laurent polynomials, and corresponding Christoffel-Darboux formulae are obtained within this point of view in a completely algebraic way. Cantero-Moral-Velazquez sequence of Laurent monomials is generalized and recursion relations, Christoffel-Darboux kernels, projecting to general spaces of truncated Laurent polynomials and corresponding Christoffel-Darboux formulae are found in this extended context. Continuous deformations of the moment matrix are introduced and ...
The Kathmandu Declaration: "Life Circle" approach to prevention and care of diabetes mellitus.
Wijesuriya, Mahen; Williams, Rhys; Yajnik, Chittaranjan
2010-01-01
To formulate strategies and action plans for the prevention and care of diabetes mellitus as part of the implementation of the International Diabetes Federation (IDF) United Nations Resolution (UNR) 61/225 through a unique concept of a "Life Circle" approach. Consensus following review of evidence available and presented at a meeting convened to achieve the objective co-chaired by the IDF President and President elect and diabetologists from several countries in the IDF regions. The Kathmandu Declaration presents the concept of a "Life Circle" approach to prevention and care of diabetes--a continuum beginning from preconception, pregnancy, infancy and childhood to adult life in an integrated manner. Emphasis is on the benefits on entering the circle at any point and formulates guidelines that could be incorporated in any national diabetes prevention and care programme, indicating the interactive role of all known aetiological factors. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.
Copelin, Michelle Renee
Research has shown that dialogic instruction promotes learning in students. Secondary science has traditionally been taught from an authoritative stance, reinforced in recent years by testing policies requiring coverage. Socratic Circles are a framework for student-led dialogic discourse, which have been successfully used in English language arts and social studies classrooms. The purpose of this research was to explore the implementation process of Socratic Circles in secondary science classes where they have been perceived to be more difficult. Focusing on two physical science classes and one chemistry class, this study described the nature and characteristics of Socratic Circles, teachers' dispositions toward dialogic instruction, the nature and characteristics of student discussion, and student motivation. Socratic Circles were found to be a dialogic support that influenced classroom climate, social skills, content connections, and student participation. Teachers experienced conflict between using traditional test driven scripted teaching, and exploring innovation through dialogic instruction. Students experienced opportunities for peer interaction, participation, and deeper discussions in a framework designed to improve dialogic skills. Students in two of the classrooms showed evidence of motivation for engaging in peer-led discussion, and students in one class did not. The class that did not show evidence of motivation had not been given the same scaffolding as the other two classes. Two physical science teachers and one chemistry teacher found that Socratic Circles required more scaffolding than was indicated by their peers in other disciplines such as English and social studies. The teachers felt that student's general lack of background knowledge for any given topic in physical science or chemistry necessitated the building of a knowledge platform before work on a discussion could begin. All three of the teachers indicated that Socratic Circles were a
Zernike expansion of derivatives and Laplacians of the Zernike circle polynomials.
Janssen, A J E M
2014-07-01
The partial derivatives and Laplacians of the Zernike circle polynomials occur in various places in the literature on computational optics. In a number of cases, the expansion of these derivatives and Laplacians in the circle polynomials are required. For the first-order partial derivatives, analytic results are scattered in the literature. Results start as early as 1942 in Nijboer's thesis and continue until present day, with some emphasis on recursive computation schemes. A brief historic account of these results is given in the present paper. By choosing the unnormalized version of the circle polynomials, with exponential rather than trigonometric azimuthal dependence, and by a proper combination of the two partial derivatives, a concise form of the expressions emerges. This form is appropriate for the formulation and solution of a model wavefront sensing problem of reconstructing a wavefront on the level of its expansion coefficients from (measurements of the expansion coefficients of) the partial derivatives. It turns out that the least-squares estimation problem arising here decouples per azimuthal order m, and per m the generalized inverse solution assumes a concise analytic form so that singular value decompositions are avoided. The preferred version of the circle polynomials, with proper combination of the partial derivatives, also leads to a concise analytic result for the Zernike expansion of the Laplacian of the circle polynomials. From these expansions, the properties of the Laplacian as a mapping from the space of circle polynomials of maximal degree N, as required in the study of the Neumann problem associated with the transport-of-intensity equation, can be read off within a single glance. Furthermore, the inverse of the Laplacian on this space is shown to have a concise analytic form.
Angiographic analysis of the circle of wills: comparison between normal and aneurysm groups
Energy Technology Data Exchange (ETDEWEB)
Lee, Eun Hye; Suh, Dae Chul; Auh, Yong Ho [Ulsan University College of Medicine, Seoul (Korea, Republic of); Lee, Sang Il [Pochon CHA University College of Medicine, Sungnam (Korea, Republic of)
1999-02-01
To evaluate angiographic variations of the circle of Willis in a normal group, and to compare the pattern of these variations between normal and aneurysm groups. We reviewed 220 cases in which subjects had undergone digital subtraction cerebral angiography which showed the circle of Willis in its entirety. One hundred patients were diagnosed as normal, and 110 had an aneurysm. We reviewed the absence or presence and relative size of each segment, and the configuration of the distal basilar artery. Where the circle was complete, we evaluated whether or not the circle was balanced. And we compared the pattern of these variations between the two groups. In the normal group, the most common pattern was a small anterior communicating artery with symmetrically large A1 segments in the anterior circulation(27%) and symmetrically small posterior communication arteries with large P1 segments in the posterior circulation(39%). The anterior half of the circle was complete in 90% of cases, and the posterior half in 63%. In cases in which it was incomplete, there was agenesis of the anterior communicating artery in 9% of cases, of the A1 segment in 1%, of the posterior communicating artery in 36%, and of the P1 segment in 3%. Unilateral absence of the posterior communicating artery and P1 segment was noted in two cases. In the distal basilar artery, symmetric cranial fusion was most common, accounting for 77% of cases. In contrast, incomplete circles with agenesis of the A1 (1% vs 12%, p < .05) or P1 segment (3% vs 10%, p < .05) were more common in the aneurysm group than among normal subjects. Unbalanced types with a size discrepancy between A1 segments(8% vs 18%, p < .05), or posterior communicating arteries equal to or larger than the P1 segment (27% vs 46%, p < .05) were also more common. In the distal basilar artery, symmetric cranial fusion was most common, and accounted for 69% of cases. A complete and balanced circle was more common in the normal group. The most common
Circle of Willis variation in a complex stroke presentation: a case report
Directory of Open Access Journals (Sweden)
Young Carolyn A
2006-03-01
Full Text Available Abstract Background The impact of circle of Willis anatomical variation upon the presentation of stroke is probably underrecognised. Case presentation A 63-year-old right-handed woman developed a left hemiparesis and right leg weakness sequentially following a road traffic accident (RTA. Despite initial concern about the possibility of cervical spinal cord injury, the final diagnosis was bilateral artery-to-artery embolic cerebral infarction with dominant right internal carotid artery. Conclusion The case illustrates the complex presentation of stroke as a pseudo-cervical cord lesion and the impact of circle of Willis anatomical variation upon the expression of large vessel cerebrovascular disease.
Amplitude variables of circle on the pedagogic pommel horse in gymnastics.
Baudry, Ludovic; Sforza, Chiarella; Leroy, David; Lovecchio, Nicola; Gautier, Geoffroy; Thouvarecq, Régis
2009-05-01
The movement amplitude is a key component of numerous elements in gymnastics. The purpose of the present study is to highlight the most pertinent amplitude variable of the circle performed on the pedagogic pommel horse. Twelve gymnasts (6 expert gymnasts vs. 6 nonexpert gymnasts) performed 10 circles on this event. A Vicon 512 system was used to record the 3-dimensional position of 11 markers fixed on the gymnasts. Our results revealed than 4 amplitude variables permitted us to significantly discriminate the levels of performance of the gymnasts (p gymnasts and to measure improvement in movements after specific training.
Empirical Research on the Urban Development Level of Wuhan Urban Circle
Directory of Open Access Journals (Sweden)
Yazhou Xiong
2013-03-01
Full Text Available The research object of this paper is the nine cities of Wuhan urban circle. Firstly, this paper establishes the comprehensive evaluation indicator system and evaluation model of the urban development level via systems analysis, then makes a PCA (Principal Components Analysis to the original data by means of SPSS; Next, this paper analyzes the worked data via AHP (Analytic Hierarchy Process and comprehensive score and ranking of the nine cities is obtained and the nine cities are divided into three clusters via K-means clustering analysis; Finally, this paper appraises urban development level of Wuhan urban circle.
Circular and linear regression fitting circles and lines by least squares
Chernov, Nikolai
2010-01-01
Find the right algorithm for your image processing applicationExploring the recent achievements that have occurred since the mid-1990s, Circular and Linear Regression: Fitting Circles and Lines by Least Squares explains how to use modern algorithms to fit geometric contours (circles and circular arcs) to observed data in image processing and computer vision. The author covers all facets-geometric, statistical, and computational-of the methods. He looks at how the numerical algorithms relate to one another through underlying ideas, compares the strengths and weaknesses of each algorithm, and il
Investigation of Brain Arterial Circle Malformations Using Electrical Modelling and Simulation
Directory of Open Access Journals (Sweden)
Klara Capova
2006-01-01
Full Text Available The paper deals with the cerebral arterial system investigation by means of electrical modelling and simulations. The main attention is paid to the brain arterial circle malformations (stenoses and aneurysms and their determination and evaluation by computer-aided methods as tools of a non-invasive diagnostics. The compensation possibilities of brain arterial circle in case of presence of concrete arterial malformations are modelled and simulated. The simulation results of brain arteries blood pressures and volume flow velocities time dependences are presented and discussed under various health conditions.
The Voronoi diagram of circles and its application to the visualization of the growth of particles
DEFF Research Database (Denmark)
Anton, François; Mioc, Darka; Gold, Christopher M.
2009-01-01
Circles are frequently used for modelling the growth of particle aggregates through the Voronoi diagram of circles, that is a special instance of the Johnson-Mehl tessellation. The Voronoi diagram of a set of sites is a decomposition of space into proximal regions. The proximal region of a site...... is the locus of points closer to that site than to any other one. Voronoi diagrams allow one to answer proximity queries after locating a query point in the Voronoi zone it belongs to. The dual graph of the Voronoi diagram is called the Delaunay graph. In this paper, we ﬁrst show a necessary and suﬃcient...
Vicious circles of punishment: a reading of Melanie Klein's Envy and gratitude.
Smith, Henry F
2008-01-01
Staged as a moral drama, Melanie Klein's Envy and Gratitude (1957) straddles two eras: one reflecting a simpler more concrete, historical method, and the other an approach of greater complexity, focused on the transferential moment. Embedded within the transference are the vicious circles of envy and punishment that are the hallmark of Klein's text. Punishment itself which is always punishment of both self and other, creates its own vicious circle, set in motion by a single act. In the sadomasochistic enactments that result, the moral force of Klein's categories fuels the countertransference. A detailed clinical hour is presented.
Collective motions of globally coupled oscillators and some probability distributions on circle
Energy Technology Data Exchange (ETDEWEB)
Jaćimović, Vladimir [Faculty of Natural Sciences and Mathematics, University of Montenegro, Cetinjski put, bb., 81000 Podgorica (Montenegro); Crnkić, Aladin, E-mail: aladin.crnkic@hotmail.com [Faculty of Technical Engineering, University of Bihać, Ljubijankićeva, bb., 77000 Bihać, Bosnia and Herzegovina (Bosnia and Herzegovina)
2017-06-28
In 2010 Kato and Jones described a new family of probability distributions on circle, obtained as Möbius transformation of von Mises distribution. We present the model demonstrating that these distributions appear naturally in study of populations of coupled oscillators. We use this opportunity to point out certain relations between Directional Statistics and collective motion of coupled oscillators. - Highlights: • We specify probability distributions on circle that arise in Kuramoto model. • We study how the mean-field coupling affects the shape of distribution of phases. • We discuss potential applications in some experiments on cell cycle. • We apply Directional Statistics to study collective dynamics of coupled oscillators.
From Death to Life – The Hydrological Circle of Cosmos and Copulation
Directory of Open Access Journals (Sweden)
Terje Oestigaard
2008-10-01
Full Text Available When a person dies, how is the soul transferred from the dead body to an infant in a mother's womb? In Hinduism this process in understood and explained metaphorically by the hydrological circle and the interrelatedness of fire and water. The cosmological circle of reincarnation is a life-giving process which includes the life-giving waters; the essence of life. Based on mythology and the sacred scriptures, this process is investigated.Key Words: Hindu Mythology, eroticism, funeral practice, sexualityDOI = 10.3126/dsaj.v2i0.1360Dhaulagiri Journal of Sociology and Anthropology Vol.2 pp.121-144
Peer Evaluation of Master Programs: Closing the Quality Circle of the CDIO Approach?
DEFF Research Database (Denmark)
Hussmann, Peter Munkebo; Bisi, Anita; Malmqvist, Johan;
2012-01-01
programs within their field at another N5T institution. The article describes the quality enhancement tool in detail, its contribution to the development of the involved programs, and how international peer evaluation can contribute to closing the quality circle. Finally, it assesses the value...... peer evaluations of educational programs to enable their further development and close the quality circle. In addition, the project will contribute to the consolidation of the N5T alliance by facilitating contacts between faculty members and providing them with an in-depth knowledge of the study...
Directory of Open Access Journals (Sweden)
Brett Cucchiara
Full Text Available OBJECTIVE: To compare the prevalence of an incomplete circle of Willis in patients with migraine with aura, migraine without aura, and control subjects, and correlate circle of Willis variations with alterations in cerebral perfusion. METHODS: Migraine with aura, migraine without aura, and control subjects were prospectively enrolled in a 1∶1∶1 ratio. Magnetic resonance angiography was performed to examine circle of Willis anatomy and arterial spin labeled perfusion magnetic resonance imaging to measure cerebral blood flow. A standardized template rating system was used to categorize circle of Willis variants. The primary pre-specified outcome measure was the frequency of an incomplete circle of Willis. The association between circle of Willis variations and cerebral blood flow was also analyzed. RESULTS: 170 subjects were enrolled (56 migraine with aura, 61 migraine without aura, 53 controls. An incomplete circle of Willis was significantly more common in the migraine with aura compared to control group (73% vs. 51%, p = 0.02, with a similar trend for the migraine without aura group (67% vs. 51%, p = 0.08. Using a quantitative score of the burden of circle of Willis variants, migraine with aura subjects had a higher burden of variants than controls (p = 0.02. Compared to those with a complete circle, subjects with an incomplete circle had greater asymmetry in hemispheric cerebral blood flow (p = 0.05. Specific posterior cerebral artery variants were associated with greater asymmetries of blood flow in the posterior cerebral artery territory. CONCLUSIONS: An incomplete circle of Willis is more common in migraine with aura subjects than controls, and is associated with alterations in cerebral blood flow.
ULYSSES comes full circle, before revisiting the Sun's poles
1998-04-01
From its unique perspective, Ulysses has provided scientists with the very first all-round map of the heliosphere, the huge bubble in space filled by the Sun's wind. The Earth swims deep inside the heliosphere, and gusts and shocks in the solar wind can harm satellites, power supplies and ommunications. They may also affect our planet's weather. A better grasp of the solar weather in the heliosphere is therefore one of the major aims of ESA's science programme. In a project of international cooperation between ESA and NASA, Ulysses was launched towards Jupiter in October 1990 by the US space shuttle Discovery. Arriving in February 1992, Ulysses stole energy from the giant planet in a slingshot manoeuvre and was propelled back towards the Sun in an elongated orbit almost at right angles to the ecliptic plane, where the Earth and other planets circle the Sun. "This month Ulysses returns to the point in space where its out-of-ecliptic journey began, but Jupiter isn't there," explains Richard Marsden, ESA's project scientist for Ulysses. "Following its own inexorable path around the Sun, Jupiter is far away on the opposite side of the Solar System. So Ulysses' course will not be changed a second time. The spacecraft is now in effect a man-made comet, forever bound into a 6-year polar orbit around the Sun." Ulysses now starts its second orbit. It will travel over the poles of the Sun in 2000-2001 just as the count of dark sunspots is expected to reach a maximum. With its operational life extended for the Ulysses Solar Maximum Mission, the spacecraft will find the heliosphere much stormier than during its first orbit. Discoveries so far Like its mythical namesake, Ulysses has already had an eventful voyage of discovery. Its unique trajectory has provided the scientific teams with a new perspective, from far out in space and especially in the previously unknown regions of the heliosphere over the Sun's poles. Passing within 9.8 degrees of the polar axis, the highly
Schmelzer, Ronald; Ramsey, Imogene
In almost every classroom there is a minority of children that, regardless of effort, teachers have difficulty working with. The "Suggestion Circle" is a method for soliciting streamlined, on-focus ideas for solving classroom problems with the help of colleagues. In the Suggestion Circle there are three roles for people: the person who…
The Two-Spectra Inverse Problem for Semi-infinite Jacobi Matrices in The Limit-Circle Case
Energy Technology Data Exchange (ETDEWEB)
Silva, Luis O., E-mail: silva@leibniz.iimas.unam.mx; Weder, Ricardo [Instituto de Investigaciones en Matematicas Aplicadas y en Sistemas, Universidad Nacional Autonoma de Mexico, Departamento de Metodos Matematicos y Numericos (Mexico)], E-mail: weder@servidor.unam.mx
2008-05-15
We present a technique for reconstructing a semi-infinite Jacobi operator in the limit circle case from the spectra of two different self-adjoint extensions. Moreover, we give necessary and sufficient conditions for two real sequences to be the spectra of two different self-adjoint extensions of a Jacobi operator in the limit circle case.
Mechtild, H.; Vogelvang, B.; Bogaerts, S.
2017-01-01
In Circles of Support and Accountability (CoSA), a group of trained and supervised volunteers support a sex offender (core member in a circle), with the aim of supporting the core member’s transitions toward full desistance. A prospective, multi-method design was used to explore psychological and so
Making a Circle: Tool Use and the Spaces where We Live
Noble, Tracy; DiMattia, Cara; Nemirovsky, Ricardo; Barros, Apolinario
2006-01-01
A group of high school students created a drawing of a circle using a device called the Drawing Machine. To describe their experiences, we propose an alternative to the idea that to master a tool one must create a mental version of the tool. We suggest, instead, that as students change their relationships to a tool over time, their lived-in spaces…
The Schur algorithm for generalized Schur functions III : J-unitary matrix polynomials on the circle
Alpay, Daniel; Azizov, Tomas; Dijksma, Aad; Langer, Heinz
2003-01-01
The main result is that for J = ((1)(0) (0)(-1)) every J-unitary 2 x 2-matrix polynomial on the unit circle is an essentially unique product of elementary J-unitary 2 x 2-matrix polynomials which are either of degree 1 or 2k. This is shown by means of the generalized Schur transformation introduced
Coles-Ritchie, Marilee
2013-01-01
This study explores the process of implementing literature circles using ethnographies as the texts to better prepare teachers for multicultural/ multilingual teaching contexts. Data collected by the course instructor and two of the participants, using a Critical Teacher Action Research (CTAR) methodology, indicate that participants think…
Analytical methods for an elliptic singular perturbation problem In a circle
Temme, N.M.
2007-01-01
We consider an elliptic perturbation problem in a circle by using the analytical solution that is given by a Fourier series with coefficients in terms of modified Bessel functions. By using saddle point methods we construct asymptotic approximations with respect to a small parameter. In particular
Analytical methods for an elliptic singular perturbation problem in a circle
Temme, N.M.
2006-01-01
We consider an elliptic perturbation problem in a circle by using the analytical solution that is given by a Fourier series with coefficients in terms of modified Bessel functions. By using saddle point methods we construct asymptotic approximations with respect to a small parameter. In particular w
Y-G. Ahn
2007-01-01
textabstractIn line with the growing importance of Corporate Sustainability Management (CSM) in business circles, the linkages between CSM, corporate values and performance is becoming increasingly higher on the agenda both for internal corporate management purposes and for external relations for co
Quasi-symmetric Conjugacy of Blaschke Products on the unit Circle
DEFF Research Database (Denmark)
Petersen, Carsten Lunde
2007-01-01
Let B be a Blaschke product for which the restriction to the unit circle 1 is a degree d > 1 covering. We prove that B is quasi-symmetrically conjugate to z zd on 1, if all its periodic points in 1 are repelling and if 1 does not intersect the -limit set of any recurrent critical point for B....
The Three Circles Redux: A Market-Theoretic Perspective on World Englishes
Park, Joseph Sung-Yul; Wee, Lionel
2009-01-01
While Kachru's Three Circles model of World Englishes (Kachru 1985, 1986; Kachru and Nelson 1996) has been highly influential in highlighting the changing distribution and functions of English, it has also been criticized for its inability to account for the heterogeneity and dynamics of English-using communities, and for perpetuating the very…
Altman, Renana; Kidron, Ivy
2016-01-01
Processes of knowledge construction are investigated. A learner is constructing knowledge about the trigonometric functions and their geometric meaning on the unit circle. The analysis is based on the dynamically nested epistemic action model for abstraction in context. Different tasks are offered to the learner. In his effort to perform the…
The Effects of Inflated Seating Cushions on Engagement in Preschool Circle Time
Seifert, Anna M.; Metz, Alexia E.
2017-01-01
Inflatable balls and cushions made of non-latex rubber can provide alternatives to sitting on the floor/ground or classroom chairs. This study tested the effect of inflatable cushions (wiggle cushions) placed on the floor for seating during circle time in typical preschool classrooms. The effect on attention was tested using alternating periods of…
Latendresse, Carter
2004-01-01
This article discusses a reading instruction applicable to widely diverse classrooms, because it weaves together dynamic strands from three approaches to teaching reading: literature circle method, reciprocal teaching, and modern literary theories. The author presents three stages to achieve reading success: (1) applying the key features of…
"Slow Down, You Move Too Fast:" Literature Circles as Reflective Practice
Sanacore, Joseph
2013-01-01
Becoming an effective literacy learner requires a bit of slowing down and appreciating the reflective nature of reading and writing. Literature circles support this instructional direction because they provide opportunities for immersing students in discussions that encourage their personal responses. When students feel their personal responses…
PT-invariance and representations of the Temperley-Lieb algebra on the unit circle
Korff, Christian
2007-01-01
We present in detail a recent conjecture on self-adjoint representations of the Temperley-Lieb algebra for particular values on the unit circle. The formulation in terms of graphical calculus is emphasized and discussed for several examples. The role of PT (parity and time reversal) invariance is highlighted as it might prove important for generalising the construction to other cases.
Runaway Climate Change as Challenge to the "Closing Circle" of Education for Sustainable Development
Selby, David; Kagawa, Fumiyo
2010-01-01
Education for sustainable development (ESD) is the latest and thickest manifestation of the "closing circle" of policy-driven environmental education. Characterised by definitional haziness, a tendency to blur rather than lay bare inconsistencies and incompatibilities, and a cozy but ill-considered association with the globalisation agenda, the…
Dinner Tables and Concentric Circles: A Harmony of Mathematics, Music, and Physics
Douthett, Jack; Krantz, Richard J.
2008-01-01
How should men and women be seated around a dinner table to maximize conversation between members of the opposite sex? What can be said about the distribution of points around two concentric circles? How are the white and black keys on the piano keyboard organized? What spin configuration in the Ising model minimizes energy? These four problems…
Classroom community and discourse: How argumentation emerges during a Socratic circle
Directory of Open Access Journals (Sweden)
Alexis Carmela Brown
2016-03-01
Full Text Available Literacy and language development is a central aspect of educational theory and practice. One area of literacy and rowlanguage research that has had a lot of attention is dialogic teaching (Bakhtin, 1984; Freire, 1970; Murphey, Wilkinson, Soter, Hennessey, & Alexander, 2009; Reznitskaya & Gregory, 2013. However, there is limited research on how high school students use their classroom discourse to construct meaning, especially in argumentation. The purpose of this data analysis is to investigate the emergence of argumentation literacy in a Socratic circle. Socratic circles, a literacy practice consisting of two concentric circles of students focused around a piece of text, are used to provide students with the opportunity to co-construct meaning through classroom dialogue (Copeland, 2005. The emergence and construction of argumentation is analyzed by applying discourse analysis to a video of a high school classroom,. Findings from this analysis reveal that through the use of exploratory talk, three discourse patterns emerge that are in line with argumentation practices: (1 generalizations, (2 communicative struggles, and (3 co-construction of ideas. Results of the analysis are discussed to inform theory and instruction on dialogic teaching and the use of Socratic circles to develop argumentation-related forms of literacy.
Detection of Veneer Moisture Content by Surface-circle-shaped Resistance
Institute of Scientific and Technical Information of China (English)
Sa Chao; Du Hongbo; Zhang Biguang; Wang Guozhu
2003-01-01
This paper, with veneer as a particularly detected target, deals with a new method for detecting veneer moisture content. Surface resistance is measured by the fixed pressure, circle-shaped point and surface-touched detector. With the help of the computer, the veneer moisture and its distribution will be detected in a faster way with no harm to the veneer surface.
"Telling Stories Long into the Night": Romantic Circles High School Project.
Walton, Brenda H.; Bork, Tara
2001-01-01
Reports on the authors' experiences in the Romantic Circles (RC) High School Project. Considers how RC High enables technology to be used as a tool in the study of literature and culture of the past, subjects that often seem dead and remote from a student's concern. (SG)
Volunteers in Circles of Support and Accountability : Job demands, job resources, and outcome
Höing, M.A.; Vogelvang, B.; Bogaerts, Stefan
2016-01-01
In Circles of Support and Accountability (CoSA), volunteers support a medium- to high-risk sex offender in his process toward desistance by developing a long-term empathic relationship. More knowledge is needed about the impact of this work on volunteers themselves. In a sample of 40 Dutch CoSA volu
Learners' Perceptions toward Pronunciation Instruction in Three Circles of World Englishes
Kang, Okim
2015-01-01
From the perspective of World Englishes (i.e., varieties of English in different regions of the world), mutual intelligibility is a key issue for both listeners and speakers. Nevertheless, learners often have an idealized notion of native-speaker spoken norms and may be in favor of more prestigious inner circle models than others. This study…
Early-Years Teachers' Concept Images and Concept Definitions: Triangles, Circles, and Cylinders
Tsamir, Pessia; Tirosh, Dina; Levenson, Esther; Barkai, Ruthi; Tabach, Michal
2015-01-01
This study investigates practicing early-years teachers' concept images and concept definitions for triangles, circles, and cylinders. Teachers were requested to define each figure and then to identify various examples and non-examples of the figure. Teachers' use of correct and precise mathematical language and reference to critical and…
Reactivation of chromosomally integrated human herpesvirus-6 by telomeric circle formation.
Directory of Open Access Journals (Sweden)
Bhupesh K Prusty
Full Text Available More than 95% of the human population is infected with human herpesvirus-6 (HHV-6 during early childhood and maintains latent HHV-6 genomes either in an extra-chromosomal form or as a chromosomally integrated HHV-6 (ciHHV-6. In addition, approximately 1% of humans are born with an inheritable form of ciHHV-6 integrated into the telomeres of chromosomes. Immunosuppression and stress conditions can reactivate latent HHV-6 replication, which is associated with clinical complications and even death. We have previously shown that Chlamydia trachomatis infection reactivates ciHHV-6 and induces the formation of extra-chromosomal viral DNA in ciHHV-6 cells. Here, we propose a model and provide experimental evidence for the mechanism of ciHHV-6 reactivation. Infection with Chlamydia induced a transient shortening of telomeric ends, which subsequently led to increased telomeric circle (t-circle formation and incomplete reconstitution of circular viral genomes containing single viral direct repeat (DR. Correspondingly, short t-circles containing parts of the HHV-6 DR were detected in cells from individuals with genetically inherited ciHHV-6. Furthermore, telomere shortening induced in the absence of Chlamydia infection also caused circularization of ciHHV-6, supporting a t-circle based mechanism for ciHHV-6 reactivation.
Approximation by polynomials and Blaschke products having all zeros on a circle
Farmer, David W
2010-01-01
We show that a nonvanishing analytic function on a domain in the unit disc can be approximated by (a scalar multiple of) a Blaschke product whose zeros lie on a prescribed circle enclosing the domain. We also give a new proof of the analogous classical result for polynomials. A connection is made to universality results for the Riemann zeta function.
Y-G. Ahn
2007-01-01
textabstractIn line with the growing importance of Corporate Sustainability Management (CSM) in business circles, the linkages between CSM, corporate values and performance is becoming increasingly higher on the agenda both for internal corporate management purposes and for external relations for
Statistics of Poincare recurrences for a class of smooth circle maps
Energy Technology Data Exchange (ETDEWEB)
Buric, Nikola [Department of Physics and Mathematics, Faculty of Pharmacy, University of Beograd, Vojvode Stepe 450, 11000 Belgrade (Serbia and Montenegro)]. E-mail: buric@phy.bg.ac.yu; Rampioni, Aldo [Department of Physics, University of Bologna, INFN Sezione di Bologna (Italy); Turchetti, Giorgio [Department of Physics, University of Bologna, INFN Sezione di Bologna (Italy)
2005-03-01
Statistics of Poincare recurrence for a class of circle maps, including sub-critical, critical, and super-critical cases, are studied. It is shown how the topological differences in the various types of the dynamics are manifested in the statistics of the return times.
The arithmetic of elliptic fibrations in gauge theories on a circle
Grimm, Thomas W.; Kapfer, Andreas; Klevers, Denis
2016-06-01
The geometry of elliptic fibrations translates to the physics of gauge theories in F-theory. We systematically develop the dictionary between arithmetic structures on elliptic curves as well as desingularized elliptic fibrations and symmetries of gauge theories on a circle. We show that the Mordell-Weil group law matches integral large gauge transformations around the circle in Abelian gauge theories and explain the significance of Mordell-Weil torsion in this context. We also use Higgs transitions and circle large gauge transformations to introduce a group law for genus-one fibrations with multi-sections. Finally, we introduce a novel arithmetic structure on elliptic fibrations with non-Abelian gauge groups in F-theory. It is defined on the set of exceptional divisors resolving the singularities and divisor classes of sections of the fibration. This group structure can be matched with certain integral non-Abelian large gauge transformations around the circle when studying the theory on the lower-dimensional Coulomb branch. Its existence is required by consistency with Higgs transitions from the non-Abelian theory to its Abelian phases in which it becomes the Mordell-Weil group. This hints towards the existence of a new underlying geometric symmetry.
The arithmetic of elliptic fibrations in gauge theories on a circle
Energy Technology Data Exchange (ETDEWEB)
Grimm, Thomas W. [Max-Planck-Institut für Physik,Föhringer Ring 6, 80805 Munich (Germany); Institute for Theoretical Physics,Utrecht University, Leuvenlaan 4, 3584 CE Utrecht (Netherlands); Center for Extreme Matter and Emergent Phenomena,Utrecht University, Leuvenlaan 4, 3584 CE Utrecht (Netherlands); Kapfer, Andreas [Max-Planck-Institut für Physik,Föhringer Ring 6, 80805 Munich (Germany); Klevers, Denis [Theory Group, Physics Department, CERN,CH-1211, Geneva 23 (Switzerland)
2016-06-20
The geometry of elliptic fibrations translates to the physics of gauge theories in F-theory. We systematically develop the dictionary between arithmetic structures on elliptic curves as well as desingularized elliptic fibrations and symmetries of gauge theories on a circle. We show that the Mordell-Weil group law matches integral large gauge transformations around the circle in Abelian gauge theories and explain the significance of Mordell-Weil torsion in this context. We also use Higgs transitions and circle large gauge transformations to introduce a group law for genus-one fibrations with multi-sections. Finally, we introduce a novel arithmetic structure on elliptic fibrations with non-Abelian gauge groups in F-theory. It is defined on the set of exceptional divisors resolving the singularities and divisor classes of sections of the fibration. This group structure can be matched with certain integral non-Abelian large gauge transformations around the circle when studying the theory on the lower-dimensional Coulomb branch. Its existence is required by consistency with Higgs transitions from the non-Abelian theory to its Abelian phases in which it becomes the Mordell-Weil group. This hints towards the existence of a new underlying geometric symmetry.
17th century arguments for the impossibility of the indefinite and the definite circle quadrature
DEFF Research Database (Denmark)
Lützen, Jesper
2014-01-01
The classical problem of the quadrature (or equivalently the rectification) of the circle enjoyed a renaissance in the second half of the 17th century. The new analytic methods provided the means for the discovery of infinite expressions of and for the first attempts to prove impossibility statem...
CHARACTERIZATION OF SINGLE-STRAND ORIGINS OF CRYPTIC ROLLING-CIRCLE PLASMIDS FROM BACILLUS-SUBTILIS
MEIJER, WJJ; VENEMA, G; BRON, S
1995-01-01
In this paper we describe the isolation and characterization of single strand origins (SSOs) of several cryptic Bacillus subtilis plasmids which use the rolling-circle mechanism of replication, The plasmids used in this study involved pTA1015, pTA1020, pTA1030, pTA1040, pTA1050 and pTA1060, The SSO
NUMERICAL SOLUTIONS FOR THE TRANSIENT FLOW IN THE HOMOGENOUS CLOSED CIRCLE RESERVOIRS
Institute of Scientific and Technical Information of China (English)
周蓉; 刘曰武; 周富信
2003-01-01
There are many fault block fields in China. A fault block field consists of fault pools.The small fault pools can be viewed as the closed circle reservoirs in some case. In order to know the pressure change of the developed formation and provide the formation data for developing the fault block fields reasonably, the transient flow should be researched. In this paper, we use the automatic mesh generation technology and the finite element method to solve the transient flow problem for the well located in the closed circle reservoir, especially for the well located in an arbitrary position in the closed circle reservoir. The pressure diffusion process is visualized and the well-location factor concept is first proposed in this paper. The typical curves of pressure vs time for the well with different welllocation factors are presented. By comparing numerical results with the analytical solutions of the well located in the center of the closed circle reservoir, the numerical method is verified.
Volunteers in circles of support and accountability : Job demands, job resources, and outcome
Höing, M.A.; Vogelvang, B.; Bogaerts, Stefan
2017-01-01
In Circles of Support and Accountability (CoSA), volunteers support a medium- to high-risk sex offender in his process toward desistance by developing a long-term empathic relationship. More knowledge is needed about the impact of this work on volunteers themselves. In a sample of 40 Dutch CoSA volu
Quasi-periodic Bifurcations of Invariant Circles in Low-dimensional Dissipative Dynamical Systems
Vitolo, Renato; Broer, Henk; Simo, Carles
2011-01-01
This paper first summarizes the theory of quasi-periodic bifurcations for dissipative dynamical systems. Then it presents algorithms for the computation and continuation of invariant circles and of their bifurcations. Finally several applications are given for quasiperiodic bifurcations of Hopf, sad
Aseron, Johnnie; Greymorning, S. Neyooxet; Miller, Adrian; Wilde, Simon
2013-01-01
Indigenous experiences, as found within traditional ways and cultural practices, are an acknowledgement of traditional methods for sharing, learning, and collective knowledge development and maintenance. The application of Cultural Safety Circles can help provide a collective space where definitions for cultural and educational exchange can take…
Two-dimensional Few-circle Optical Pulses in the Inhomogeneous Environment of Carbon Nanotubes
Directory of Open Access Journals (Sweden)
M.B. Belonenko
2015-12-01
Full Text Available We consider the task about few-circle optical pulses dynamics (light bullets in the inhomogeneous environment of carbon nanotubes. Electromagnetic field of pulse describes classically, on basis of Maxwell equation, and carbon nanotubes give dispersion law for electrons, which interacting with pulse. We show that light bullets propagate stably.
Abdelrasoul, Mohamed Mahmoud Ibrahim
2014-01-01
The present study aimed at developing the necessary critical reading skills and social skills of the Egyptian EFL second year preparatory school students, through a proposed program based on using reading circles strategy. The study participants were 44 students from Sohag Experimental Preparatory School in Sohag Governorate. Instruments of the…
STEM High School Teachers' Views of Implementing PBL: An Investigation Using Anecdote Circles
deChambeau, Aimée L.; Ramlo, Susan E.
2016-01-01
Problem-based learning (PBL) has been gaining in popularity, especially within the context of STEM-based (science, technology, engineering, and mathematics) schools. Program assessments for these schools typically focus on student standardized test scores rather than the needs of the teachers. This study utilized anecdote circles, storytelling via…
Y-G. Ahn
2007-01-01
textabstractIn line with the growing importance of Corporate Sustainability Management (CSM) in business circles, the linkages between CSM, corporate values and performance is becoming increasingly higher on the agenda both for internal corporate management purposes and for external relations for co
Treatment of infraorbital dark circles using 694-nm fractional Q-switched ruby laser.
Xu, Tian-Hua; Li, Yuan-Hong; Chen, John Z S; Gao, Xing-Hua; Chen, Hong-Duo
2016-12-01
The objective of this study was to evaluate the efficacy and safety of using a 694-nm fractional Q-switched ruby laser to treat infraorbital dark circles. Thirty women with infraorbital dark circles (predominant color: dark/brown) participated in this open-labeled study. The participants received eight sessions of 694-nm fractional Q-switched ruby laser treatment using a fluence of 3.0-3.5 J/cm(2), at an interval of 7 days. The melanin deposition in the lesional skin was observed in vivo using reflectance confocal microscopy (RCM). The morphological changes were evaluated using a global evaluation, an overall self-assessment, and a Mexameter. Twenty-eight of the 30 patients showed global improvements that they rated as excellent or good. Twenty-six patients rated their overall satisfaction as excellent or good. The melanin index indicated a substantial decrease from 240.44 (baseline) to 194.56 (P dark/brown infraorbital dark circles is caused by increased melanin deposition in the upper dermis. The treatment of these infraorbital dark circles using a 694-nm fractional QSR laser is safe and effective.
Inquiry into Lemercier de la Rivière’s entry into the circle of Quesnay.
Bernard Herencia
2013-01-01
This paper proposes a new reading of the sources to release a new dating for entering Lemercier de la Rivière in intellectual circles of Quesnay and Mirabeau. In doing so, this Physiocrat generally accepted by commentators as a secondary author of the school led by Quesnay, appears as one of its founders.
Dear Nel: Opening the Circles of Care (Letters to Nel Noddings)
Lake, Robert
2012-01-01
This collection is a moving tribute to Nel Noddings, a fascinating and influential scholar who has contributed greatly to numerous fields, including education, feminism, ethics, and the study of social justice and equity. "Dear Nel: Opening the Circles of Care" presents contributions from renowned teachers, educators, and activists, such as David…
Penentuan Segmen Pasar Produk Private Label Makanan Siap Saji (Studi Pada Circle K Surabaya)
2015-01-01
Segmentasi pasar memberikan peluang bagi peritel guna menyesuaikan produknya dengan permintaan konsumen. Penelitian ini bertujuan untuk mengetahui segmen pasar produk private label makanan siap saji di Circle K. Penelitian menggunakan analisis deskriptif untuk menggambarkan karakteristik konsumen dari variabel demografis, geografis, dan perilaku, analisis cluster K-Mean untuk menentukan segmen pasar dari variabel psikografis, analisis SWOT untuk menyusun faktor-faktor strategis perusahaan. Ha...
Runaway Climate Change as Challenge to the "Closing Circle" of Education for Sustainable Development
Selby, David; Kagawa, Fumiyo
2010-01-01
Education for sustainable development (ESD) is the latest and thickest manifestation of the "closing circle" of policy-driven environmental education. Characterised by definitional haziness, a tendency to blur rather than lay bare inconsistencies and incompatibilities, and a cozy but ill-considered association with the globalisation agenda, the…
A Study of Traditional Circle Games Played in Public School Kindergartens across the United States.
Rothlein, Liz; And Others
1988-01-01
Investigates traditional circle games played in 203 public school kindergartens in 35 states. Results indicate that music/movement and racing games were the major game categories; the most common frequency and duration was three times per week for 20 minutes; and the purposes of the games were to have fun, and to foster social, physical motor, and…
The rolling-circle melting-pot model for porcine circovirus DNA replication
A stem-loop structure, formed by a pair of inverted repeats during DNA replication, is a conserved feature at the origin of DNA replication (Ori) among plant and animal viruses, bacteriophages and plasmids that replicate their genomes via the rolling-circle replication (RCR) mechanism. Porcine circo...
Embedding and Distributing Constant Time Delay in Circle Time and Transitions.
Wolery, Mark; Anthony, Leslie; Caldwell, Nicola K.; Snyder, Erin D.; Morgante, James D.
2002-01-01
This study evaluated embedding and distributing constant time delay instructional trials into circle time and transitions between activities in a summer camp program. Three boys (ages 5-8) with disabilities or behavior problems participated. Results indicated the children acquired the behaviors they were taught and generalized the learned…
"Slow Down, You Move Too Fast:" Literature Circles as Reflective Practice
Sanacore, Joseph
2013-01-01
Becoming an effective literacy learner requires a bit of slowing down and appreciating the reflective nature of reading and writing. Literature circles support this instructional direction because they provide opportunities for immersing students in discussions that encourage their personal responses. When students feel their personal responses…
Infinite-Dimensional Feedback Systems : The Circle Criterion and Input-to-State Stability
Jayawardhana, Bayu; Logemann, Hartmut; Ryan, Eugene P.
2008-01-01
An input-to-state stability theory, which subsumes results of circle criterion type, is developed in the context of a class of infinite-dimensional systems. The generic system is of Lur’e type: a feedback interconnection of a well-posed infinite-dimensional linear system and a nonlinearity. The
Youth Voter Turnout 1992 to 2004: Estimates from Exit Polls. CIRCLE Fact Sheet.
Center for Information and Research on Civic Learning and Engagement, 2005
2005-01-01
CIRCLE has issued two releases estimating youth turnout in the 2004 presidential election. The first release was issued on November 3rd and provided the earliest turnout estimates based on National Election Pool (NEP) state and national exit polls and a preliminary vote count. The second was a Fact Sheet released on November 8th which provided…
Integer Programming Formulations for Approximate Packing Circles in a Rectangular Container
Directory of Open Access Journals (Sweden)
Igor Litvinchev
2014-01-01
Full Text Available A problem of packing a limited number of unequal circles in a fixed size rectangular container is considered. The aim is to maximize the (weighted number of circles placed into the container or minimize the waste. This problem has numerous applications in logistics, including production and packing for the textile, apparel, naval, automobile, aerospace, and food industries. Frequently the problem is formulated as a nonconvex continuous optimization problem which is solved by heuristic techniques combined with local search procedures. New formulations are proposed for approximate solution of packing problem. The container is approximated by a regular grid and the nodes of the grid are considered as potential positions for assigning centers of the circles. The packing problem is then stated as a large scale linear 0-1 optimization problem. The binary variables represent the assignment of centers to the nodes of the grid. Nesting circles inside one another is also considered. The resulting binary problem is then solved by commercial software. Numerical results are presented to demonstrate the efficiency of the proposed approach and compared with known results.
Institute of Scientific and Technical Information of China (English)
ZHANG Xuewen; XUAN Wei; JIANG Tao; JI Degang; YANG Yongsheng; ZHANG Dan; XIE Yingjun; MENG Zihui; ZHAO Jisheng
2007-01-01
The aim of this paper is to summarize the methods of pancreaficojejunostomy in the pancreatic operation and to study the safety and feasibility of a new operative method called end-to-end invagination pancreaticojejunostomy with circle discontinuous U suture to prevent fistula of pancreaticojejunostomy.Eight-three patients with pancreaticoduodenectomy in the 3rd Hospital,Jilin University from 2001 January to 2006 April were reviewed.The incidences of pancreatic fistula with different types of pancreaticojejunostomy were compared.The overall incidence rate of pancreatic fistula was 26.5% (22/83).No pancreatic fistula occurred in end-to-end invagination pancreaticojejunostomy with circle discontinuous U suture.The incidence rate of the fistula following end-to-end invagination pancreaticojejunostomy with circle discontinuous U suture was significantly lower than that of traditional end-to-end pancreaticojejunostomy [40%,(10/25),P＜0.01] and end-to-side pancreaticojejunostomy [27.3%,(12/44),P ＜ 0.05],but no significant difference (P＞0.05) between traditional end-to-end pancreaticojejunostomy and end-to-side pancreaticojejunostomywas discovered.End-to-end invagination pancreaticojejunostomy with circle discontinuous U suture has a definite effect on avoiding pancreatic fistula following pancreaticojejunostomy and is worth being recommended.But the cases were limited,so this method would still need to be observed and confirmed further in the future.
Education, Enlightenment and Positivism: The Vienna Circle's Scientific World-Conception Revisited
Uebel, Thomas E.
2004-01-01
The scientific world-conception is properly understood as an enlightenment philosophy only if the current reassessment of the historical Vienna Circle(as opposed to the caricature still prevalent in the popular philosophical imagination) is once more extended to comprehend not only its thorough-going epistemological anti-foundationalism, but also…
The Influence of Quality Circles on Attitudinal Outcomes Among Civil Engineering Personnel.
1985-09-01
hygiene factors are related to job context. Herzberg recommends that jobs should be *enriched" by making the work more meaningful and interesting. He...34 Quality Progress, 13: 30-33 (1980b). Crawford, Maj Frederick L. "Quality Circles Results Measurement in the Federal Sector." Report to Air Command
Quality circles to improve prescribing of primary care physicians. Three comparative studies.
Wensing, M.J.P.; Broge, B.; Riens, B.; Kaufmann-Kolle, P.; Akkermans, R.P.; Grol, R.P.T.M.; Szecsenyi, J.
2009-01-01
PURPOSE: To determine the effectiveness of quality circles on prescribing patterns of primary care physicians in Germany and to explore the influence of specific factors on changes. METHODS: Three large non-randomised comparative studies were performed in primary care in Germany, with baseline measu
Circle of Security in Child Care: Putting Attachment Theory into Practice in Preschool Classrooms
Cooper, Glen; Hoffman, Kent; Powell, Bert
2017-01-01
This article describes the Circle of Security-Classroom (COS-C) approach to applying attachment theory in preschool settings. Early childhood is an incubator for a wide range of development including the underpinnings of school readiness. Secure teacher-child relationships support this process. However, most preschool staff members lack guidance…
The Arithmetic of Elliptic Fibrations in Gauge Theories on a Circle
Grimm, Thomas W; Klevers, Denis
2016-01-01
The geometry of elliptic fibrations translates to the physics of gauge theories in F-theory. We systematically develop the dictionary between arithmetic structures on elliptic curves as well as desingularized elliptic fibrations and symmetries of gauge theories on a circle. We show that the Mordell-Weil group law matches integral large gauge transformations around the circle in Abelian gauge theories and explain the significance of Mordell-Weil torsion in this context. We also use Higgs transitions and circle large gauge transformations to introduce a group law for genus-one fibrations with multi-sections. Finally, we introduce a novel arithmetic structure on elliptic fibrations with non-Abelian gauge groups in F-theory. It is defined on the set of exceptional divisors resolving the singularities and divisor classes of sections of the fibration. This group structure can be matched with certain integral non-Abelian large gauge transformations around the circle when studying the theory on the lower-dimensional ...
Mending the Broken Circle: Treatment of Substance Dependence among Native Americans.
Garrett, Michael Tlanusta; Carroll, Jane J.
2000-01-01
Issues surrounding substance dependence of Native Americans are examined through the cultural concept of the Broken Circle. Traditional cultural views of wellness and healing are described. Underlying factors in substance dependence of Native Americans are presented along with practical counseling recommendations and implications for treatment…
Tunç-Pekkan, Zelha
2015-01-01
It is now well known that fractions are difficult concepts to learn as well as to teach. Teachers usually use circular pies, rectangular shapes and number lines on the paper as teaching tools for fraction instruction. This article contributes to the field by investigating how the widely used three external graphical representations (i.e., circle,…
Circle of Security in Child Care: Putting Attachment Theory into Practice in Preschool Classrooms
Cooper, Glen; Hoffman, Kent; Powell, Bert
2017-01-01
This article describes the Circle of Security-Classroom (COS-C) approach to applying attachment theory in preschool settings. Early childhood is an incubator for a wide range of development including the underpinnings of school readiness. Secure teacher-child relationships support this process. However, most preschool staff members lack guidance…
Quantization of Sine-Gordon solitons on the circle: semiclassical vs. exact results
Pawellek, Michael
2008-01-01
We consider the semiclassical quantization of sine-Gordon solitons on the circle with periodic and anti-periodic boundary conditions. The 1-loop quantum corrections to the mass of the solitons are determined using zeta function regularization in the integral representation. We compare the semiclassical results with exact numerical calculations in the literature and find excellent agreement even outside the plain semiclassical regime.
Using Social Networks and ICTs to Enhance Literature Circles: A Practical Approach
Walker, Andrea
2010-01-01
The purpose of this paper is to describe and demonstrate how social networks such as "Facebook" and "Goodreads", and information and communication technologies (ICTs) tools like laptops and iPods can support and enhance literature circles. The innovation described is implemented by the library and aims to promote reading for…
An anatomical study of normal variations of circle of Willis in 132 fetus, newborn and adult
Directory of Open Access Journals (Sweden)
Bateni F
2009-09-01
Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Several studies have investigated the variations in the anatomy of each segment of circle of Willis whereas a few have addressed the variations of this arterial circle as a whole. In this study the entire circle of Willis and its variations were studied in a cohort of Iranian people and compared with previous reports."n"nMethods: Anatomical variations of the circle of Willis in 132 brains of Iranian cadavers (102 male adults and 30 fetuses and infants were studied. The dissection process was digitally filmed for further studies. Using computer software the external diameters of the vessels were measured and the circle variations were classified. The variations of the circle as a whole and segmental variations were compared with previous studies. "n"nResults: Uni-and bilateral hypoplasia of posterior communicating arteries (PcoAs constituted the most common variation in our study which was similar to previous works. Aplasia of the anterior cerebral artery (A1 and the posterior cerebral artery (P1 were not observed. In 3.3% of fetuses and infants and 3% of adult instances both right and left posterior communicating arteries were absent. There was one case of anterior communicating artery (AcoA aplasia in
Directory of Open Access Journals (Sweden)
Ovchintsev Mikhail Petrovich
2014-04-01
Full Text Available This paper considers the problem of optimal recovery of bounded analytic functions. Namely, the values of these functions are determined at the point from their values at n given points lying in the unit circle. At first, we recall the necessary basic concepts: error of approximation by some method (which is a complex function of n complex variables, the best approximation method. Some theorems from the works of K.U. Osipenko are discussed: on the existence of a best linear approximation method and on calculating the error of best recovery method. After that we write out the formula for finding the error of best approximation method of bounded analytic functions in a unit circle. The lemma of conformal invariance of optimal recovery problem of these functions follows. We prove that under conformal mapping of the unit circle onto itself the error of the best approximation method before mapping coincides with the error of the best approximation method after mapping. It is also proved that a linear best method after conformal mapping coincides with the linear best restore method before this mapping (wherein the problem of optimal recovery after mapping is considered on the images of n given points lying in the original unit circle. Finally, we consider the problem of optimal recovery of bounded analytic functions in a circle in special case when the given points coincide with the vertices of a regular n-gon, and the point itself coincides with its center (which coincides with the origin. We prove that all the coefficients of the best linear method in this case are identical (wherein we apply the lemma of conformal invariance of optimal recovery problem of bounded analytic functions. The formulas for calculating these coefficients are given (for this purpose we write out an integral. The result is the smart, simple formulas for calculating the coefficients of the best linear approximation method for this particular case.
Enhanced x-ray resolving power achieved behind the focal circles of Cauchois spectrometers.
Seely, John F; Hudson, Lawrence T; Holland, Glenn E; Henins, Albert
2008-05-20
Maintaining high resolving power is a primary challenge in hard x-ray spectroscopy of newly developed bright and transient x-ray sources such as laser-produced plasmas. To address this challenge, the line widths in x-ray spectra with energies in the 17 keV to 70 keV range were recorded by positioning the detectors on and behind the focal circles of Cauchois type transmission-crystal spectrometers. To analyze and understand the observed line widths, we developed a geometrical model that accounts for source broadening and various instrumental broadening mechanisms. The x-ray sources were laboratory Mo or W electron-bombarded anodes, and the spectra were recorded on photostimulable phosphor image plates. For these relatively small x-ray sources, it was found that when the detector was placed on or near the focal circle, the line widths were dominated by the effective spatial resolution of the detector. When the detector was positioned beyond the focal circle, the line widths were determined primarily by source-size broadening. Moreover, the separation between the spectral lines increased with distance behind the focal circle faster than the line widths, resulting in increased resolving power with distance. Contributions to line broadenings caused by the crystal thickness, crystal rocking curve width, geometrical aberrations, and natural widths of the x-ray transitions were in all cases smaller than detector and source broadening, but were significant for some spectrometer geometries. The various contributions to the line widths, calculated using simple analytical expressions, were in good agreement with the measured line widths for a variety of spectrometer and source conditions. These modeling and experimental results enable the design of hard x-ray spectrometers that are optimized for high resolving power and for the measurement of the x-ray source size from the line widths recorded behind the focal circle.
New mechanized system for circle spraying of oil palms seedling emergence
Directory of Open Access Journals (Sweden)
Darius El Pebrian
2012-04-01
Full Text Available A new machine system has been designed, developed and evaluated for extensive circle spraying of oil palms (Elaeis guineensis Jacq. in an effort to overcome the inefficient spraying problem with the conventional spraying system. The machine system consists of a four-wheeled drive 4WD prime mover with front mounted machine attachments for the circle spraying operation. The configuration of the circle spraying attachment consists of a hexagonal curved spray boom, lifting arm, opening-tilting mechanism unit, storage tank, spray pump, solid cone nozzles, and associate hydraulic system. Field performance tests on the machine system showed an average effective field capacity of 7.89 ha per man per day and when compared to the earlier reported effective field capacity of the walking spray-operated equipment using Serena LT16 knapsack sprayer; a difference of 1.97 time for circle spraying of mature palms grove. Reduction in the human energy expenditure of 101.28 kJ man-1 h-1 or 10.68 % but an increase in the spraying cost of 1.53 USD ha-1 or 24.9 % were obtained with the machine system against the walking spraying-operated equipment using Serena LT16 knapsack sprayer. Justification for machine system to be cost effective could be satisfied if the present effective field capacity is increased to 1.263 time with good skilled operator or if the current R&D cost is reduced to 0.41 time. This is because the improved field capacity of new machine system could not rationalize its current R&D cost. Admittedly, the machine system has great potential to overcome the limitations with the current employed machine/equipment in the circle spraying operation of oil palms in the plantation.
一种工程图中圆的整体识别方法%A Method of Global Recogniting Circles about Engineering Drawing
Institute of Scientific and Technical Information of China (English)
张显全
2003-01-01
In study on recognition of engineering drawings,the recognition for circle is a key technology. A newmethod of global recognition circle about engineering drawing is presented. Image of engineering drawing is process-ed. It depends on the circular arc of the image,the circle or circular arc is global recognized by tracing the circle direc-tion and region. Experimental results show that the method is feasibility and availability.
Cerebral cross-perfusion and the Circle of Willis: does physiology trump anatomy?
Directory of Open Access Journals (Sweden)
Musicki K
2017-07-01
Full Text Available Korana Musicki,1 Katherine Victoria Hurst,1,2 Zoltán Molnár,3 Elizabeth Hardy,4 Ashok Handa,1,2 1Department of Vascular Surgery, John Radcliffe Hospital, 2Nuffield Department of Surgical Sciences, 3Department of Physiology, Anatomy and Genetics, University of Oxford, 4Vascular Studies Unit, John Radcliffe Hospital, Oxford, UK Introduction: Cerebral cross-perfusion is essential for ipsilateral brain viability during unilateral insult. Aortic arch and great vessel procedures depend on its function for safe practice, unless adjuncts like shunts are used. This paper assesses the contribution of cerebrovascular anatomy against physiology in determining requisite hemispheric perfusion during carotid endarterectomy (CEA.Materials and methods: A review of shunting requirements for CEAs under locoregional anesthesia (LA at the John Radcliffe Hospital during 1999–2013 was performed. A PubMed search for “Circle of Willis” was screened for all original articles defining cerebrovascular anatomy by postmortem or angiography.Results: Over 14 years, 1137 CEAs were performed under cervical plexus block; during this period, the departmental standard of practice evolved from exclusively general anesthesia to predominantly LA. CEAs performed under LA during the early phase (1999–2003 had a shunt rate of 15.1%, compared to 20% as predicted by stump pressures alone. However, shunting decreased as higher perioperative systolic pressures were routinely practiced; shunt rates were 8.0% during the intermediate (2004–2007 and 6.4% during the later (2008–2013 phase. By comparison, 25 articles characterizing 6414 brains report an intact circle of Willis in 33–35% of people, with a complete hemi-circle anteriorly (77% seen more commonly than posteriorly (42%, and 11–16% deficient in both hemi-circles with no cross-flow.Conclusion: Cerebral cross-perfusion is fundamental for safe CEA. Anatomy of the circle of Willis alone does not itself determine adequacy
Institute of Scientific and Technical Information of China (English)
Zhubin He; Z. R. Wang; Kunpeng Kang
2004-01-01
The Mohr stress circle for three-dimensional stress is usually determined by equations,which is lack of intuitionistic meanings and difficult to understand. In this paper, the construction of Mohr stress circle is illustrated directly by numerical method. The shortcoming of Mohr stress circle in representing the stress components on different oblique planes for three-dimensional stress is analyzed. A three-dimensional figure is given to describe the variation of normal and shear stress on different oblique planes at one point for the first time.
Strange non-chaotic attractors in quasiperiodically forced circle maps: Diophantine forcing
Jäger, T
2011-01-01
We study parameter families of quasiperiodically forced (qpf) circle maps with Diophantine frequency. Under certain C1-open conditions concerning their geometry, we prove that these families exhibit nonuniformly hyperbolic behaviour, often referred to as the existence of strange nonchaotic attractors, on parameter sets of positive measure. This provides a nonlinear version of results by Young on quasiperiodic SL (2;R)-cocycles and complements previous results in this direction which hold for sets of frequencies of positive measure, but did not allow for an explicit characterisation of these frequencies. As an application, we study a qpf version of the Arnold circle map and show that the Arnold tongue corresponding to rotation number 1/2 collapses on an open set of parameters. The proof requires to perform a parameter exclusion with respect to some twist parameter and is based on the multiscale analysis of the dynamics on certain dynamically defined critical sets. A crucial ingredient is to obtain good control...
Directory of Open Access Journals (Sweden)
Lütfi İncikabı
2015-04-01
Full Text Available The purpose of this study is to determine seventh grade students’ preferences among the procedural, conceptual and graphical questions in the subject of circles, to define their success levels in their preferences, and to compare students’ success levels in one question type with their performances in other question types. The methodology adopted during this research was case study. Based on criterion-based purposive sampling strategy, 98 middle school students were selected as the participants. Data were collected through an achievement test consisting of nine questions (three per question type. The results obtained from the study indicated that students mostly preferred graphical question types. Moreover, majority of students could not succeeded high levels in their preferred question types. In addition, the students performed better in graphical question types; however, the failure in procedural question types was remarkable. Keywords: Multiple representations, middle school students, mathematics education, circles
Analysis of the symmetric configuration of the circle of Willis in a series of autopsied corpses
Directory of Open Access Journals (Sweden)
Stojanović Nebojša
2015-01-01
Full Text Available Introduction. The forming of the blood vessels network configuration at the base of the brain and interconnecting of blood vessels during the embryogenesis is directly related to the phylogenetic development of the brain and brain structures. A blood vessel configuration at the brain base, in the form of a ring or a hexagon, stands in direct relation to the perfusion needs of certain parts of the brain during its primary differentiation. The aim of this paper was to determine the incidence of certain blood vessel configurations at the base of the brain and understanding their symmetry or asymmetry. Methods. Analysis of the blood vessels at the base of the brain was performed on the autopsied subjects. The object of observation was the anterior segment of the circle of Willis consisting of C1- a. carotis interna (ICA, above a. communicaus posterior (PcoA, the segment A1 a. cerebri anterior (ACA from a. carotis interna bifurcation to the a. communicans anterior (AcoA and a. communicans anterior itself, as well as the posterior segment consisting of PcoA and the segment P1 - a. cerebri posterior (PCA from the a. basilaris bifurcation to the PcoA. For the purpose of grouping the findings, the four basic configuration types of the circle of Willis were identified based on its symmetry or asymmetry. Type-A (symmetric circle of Willis, type-B (asymmetric circle of Willis' due to the unilateral hypoplastic A1-ACA; type-C (symmetric circle of Willis with bilateral symmetric changes on PcoA and type-D (asymmetric circle of Willis due to the asymmetric changes on PcoA. Results. Autopsy was performed on 56 corpses. A total of 41 (73.2% subjects were recorded with a symmetric configuration of the circle of Willis', of which 27 (48.2% subjects had type A and 14 (25% type C. The asymmetric configuration was present in 15 (26.8% subjects, of whom 9 (16% had type B and 6 (10.8% type D. The symmetric Willis group (73.2% did not have a homogeneous finding that
Pythagorean hodograph spline spirals that match G3 Hermite data from circles
Li, Zhong
2015-04-01
A construction is given for a G3 piecewise rational Pythagorean hodograph convex spiral which interpolates two G3 Hermite data associated with two non-concentric circles, one being inside the other. The spiral solution is of degree 7 and is the involute of a G2 convex curve, referred to as the evolute solution, with prescribed length, and composed of two PH quartic curves. Conditions for G3 continuous contact with circles are then studied and it turns out that an ordinary cusp at each end of the evolute solution is required. Thus, geometric properties of a family of PH polynomial quartics, allowing to generate such an ordinary cusp at one end, are studied. Finally, a constructive algorithm is described with illustrative examples.
Integrated photonic 3D waveguide arrays for quantum random walks on a circle
Linjordet, Trond
2010-01-01
Quantum random walks (QRWs) can be used to perform both quantum simulations and quantum algorithms. In order to exploit this potential, quantum walks on different types of graphs must be physically implemented. To this end this we design, model and experimentally fabricate, using the femtosecond laser direct-write technique, a 3D tubular waveguide array within glass to implement a photonic quantum walk on a circle. The boundary conditions of a QRW on a circle naturally suggests a 3D waveguide implementation - allowing much simpler device design than what could be achieved using a 2D waveguide architecture. We show that, in some cases, three-dimensional photonic circuits can be more suited to the simulation of complex quantum phenomena.
Dermoscopy of verrucous epidermal nevus: large brown circles as a novel feature for diagnosis.
Carbotti, Mattia; Coppola, Rosa; Graziano, Antonio; Verona Rinati, Maria; Paolilli, Francesco Luigi; Zanframundo, Salvatore; Panasiti, Vincenzo
2016-06-01
The epidermal nevus is a hamartomatous proliferation of the epithelium that can involve keratinocytes, sebaceous glands, the pilosebaceous unit, and eccrine or apocrine glands. It occurs in one in 1000 live births and most commonly presents as the verrucous type. Dermoscopy is a non-invasive technique commonly used to differentiate between melanocytic and non-melanocytic lesions. This study was performed to analyze dermoscopic aspects of verrucous epidermal nevi, which have not previously been described. Dermoscopic analyses of eight different verrucous epidermal nevi were conducted. Each lesion was excised, and its diagnosis was histopathologically confirmed. In non-melanocytic lesions, a new dermoscopic feature of large brown circles was observed. This characteristic is useful in the diagnosis of verrucous epidermal nevi. Large brown circles represent a specific dermoscopic feature for the diagnosis of verrucous epidermal nevus. © 2015 The International Society of Dermatology.
Shared inputs and desynchrony in elliptic bursters: from slow passage to discontinuous circle maps
Lajoie, Guillaume
2010-01-01
What input signals will lead to synchrony vs. desynchrony in a group of biological oscillators? This question connects with both classical dynamical sys- tems analyses of entrainment and phase locking and with emerging studies of stimulation patterns for controlling neural network activity. Here, we focus on the response of a population of uncoupled, elliptically bursting neurons to a com- mon pulsatile input. We extend a phase reduction from the literature to capture inputs of varied strength, leading to a circle map with discontinuities of various orders. In a combined analytical and numerical approach, we apply our results to both a normal form model for elliptic bursting and to a biophysically-based model for neurons of the basal ganglia. We find that, depending on the period and amplitude of inputs, the response can either appear chaotic (with provably positive Lyaponov exponent for the associated circle maps), or periodic with a broad range of phase-locked periods. Throughout, we discuss the critical un...
Bells Galore: Oscillations and circle-map dynamics from space-filling fractal functions
Energy Technology Data Exchange (ETDEWEB)
Puente, C.E.; Cortis, A.; Sivakumar, B.
2008-10-15
The construction of a host of interesting patterns over one and two dimensions, as transformations of multifractal measures via fractal interpolating functions related to simple affine mappings, is reviewed. It is illustrated that, while space-filling fractal functions most commonly yield limiting Gaussian distribution measures (bells), there are also situations (depending on the affine mappings parameters) in which there is no limit. Specifically, the one-dimensional case may result in oscillations between two bells, whereas the two-dimensional case may give rise to unexpected circle map dynamics of an arbitrary number of two-dimensional circular bells. It is also shown that, despite the multitude of bells over two dimensions, whose means dance making regular polygons or stars inscribed on a circle, the iteration of affine maps yields exotic kaleidoscopes that decompose such an oscillatory pattern in a way that is similar to the many cases that converge to a single bell.
On Linear Combinations of Two Orthogonal Polynomial Sequences on the Unit Circle
Directory of Open Access Journals (Sweden)
Suárez C
2010-01-01
Full Text Available Let be a monic orthogonal polynomial sequence on the unit circle. We define recursively a new sequence of polynomials by the following linear combination: , , . In this paper, we give necessary and sufficient conditions in order to make be an orthogonal polynomial sequence too. Moreover, we obtain an explicit representation for the Verblunsky coefficients and in terms of and . Finally, we show the relation between their corresponding Carathéodory functions and their associated linear functionals.
Borchardt, Sarah
2014-01-01
We describe the intensity distribution of the parhelic circle for plate-oriented hexagonal ice crystals at very low solar elevations using geometrical optics. An experimental as well as theoretical study of in-plane ray-paths provides details on the mechanism for several halos, including the parhelia, the $120^{\\circ}$ parhelia, the blue spot and the Liljequist parhelia. Azimuthal coordinates for associated characteristic features in the intensity distribution are compared to data obtained using a rotating hexagonal glass prism.
A topological state sum model for a scalar field on the circle
Kerr, Steven
2016-01-01
This paper is a follow-up to a previous paper on fermions. A simple state sum model for a scalar field on a triangulated 1-manifold is constructed. The model is independent of the triangulation and gives exactly the same partition function as the continuum functional integral with zeta function regularisation. For a certain choice of gauge group, the state sum model on the circle is equivalent to the path integral for the simple harmonic oscillator.
Right-invariant Sobolev metrics ${H}^{s}$ on the diffeomorphisms group of the circle
Escher, Joachim
2012-01-01
We study the geodesic flow on the diffeomorphisms group of the circle with respect to the right-invariant metric induced by the fractional Sobolev norm $H^s$ for $s\\ge1/2$. We show that the corresponding initial value problem possesses a maximal solution in the smooth category and that the Riemannian exponential mapping is a smooth diffeomorphism from a neighbourhood of 0 in $C^{\\infty}(S)$ onto a neighbourhood of the identity in $Diff^{\\infty}(S)$.
Thermodynamic formalism and circle homeophormisms with a break-type singularity
Dzhalilov, A A
2002-01-01
A renormalization group (RG) transformation on the space of circle homeomorphisms with break-type singularity point and with the rotation number $\\rho =\\genfrac{\\sqrt{5}-1}{2}$ (``golden mean'') has a unique periodic trajectory $\\{T_{1},T_{2}\\}$ with period two. For homeomorphisms $T$ which are $C^{1}-$conjugate to $T_{1}$ $($ or $T_{2})$ the behavior of Holder's exponents of singular invariant measure are studied. Limit distributions of entrance times are also studied.
Infinite-Dimensional Feedback Systems: The Circle Criterion and Input-to-State Stability
2008-01-01
An input-to-state stability theory, which subsumes results of circle criterion type, is developed in the context of a class of infinite-dimensional systems. The generic system is of Lur’e type: a feedback interconnection of a well-posed infinite-dimensional linear system and a nonlinearity. The class of nonlinearities is subject to a (generalized) sector condition and contains, as particular subclasses, both static nonlinearities and hysteresis operators of Preisach type.
Mitra, Jubin
2013-01-01
The Circle of Willis is in the junction of two carotid arteries and two vertebral arteries that supply the brain with nutrition. Junctions where these arteries come together may develop weak spots that can balloon out and fill with blood, creating aneurysms. These sac-like areas may leak or rupture, spilling blood into surrounding tissues which may cause artery spasm leading to potential stroke or even death. Clipping and coiling are two treatment options preferred by neurosurgeon which requi...
The partition function of a multi-component Coulomb gas on a circle
Energy Technology Data Exchange (ETDEWEB)
Jokela, Niko; Keski-Vakkuri, Esko [Helsinki Institute of Physics, University of Helsinki, PO Box 64, FIN-00014 (Finland); Jaervinen, Matti [University of Southern Denmark, Campusvej 55, DK-5230 Odense M (Denmark)], E-mail: niko.jokela@helsinki.fi, E-mail: mjarvine@ifk.sdu.dk, E-mail: esko.keski-vakkuri@helsinki.fi
2008-04-11
We study a two-dimensional Coulomb gas consisting of a mixture of particles carrying various positive multiple integer charges, confined on a unit circle. We consider the system in the canonical and grand canonical ensembles, and attempt to calculate the partition functions analytically, using Toeplitz and confluent Vandermonde determinants. Just like in the simple one-component system (Dyson gas), the partition functions simplify at special temperature {beta} = 2, allowing us to find compact expressions for them.
4D/3D reduction of dualities: mirrors on the circle
Energy Technology Data Exchange (ETDEWEB)
Amariti, Antonio [LPTENS - UMR CNRS 8549,24, rue Lhomond, 75231 Paris (France); Forcella, Davide [Physique Théorique et Mathématique and International Solvay Institutes, ULB,C.P. 231, 1050 Bruxelles (Belgium); Klare, Claudius [IPHT, CEA/Saclay,91191 Gif-sur-Yvette (France); IHES,35, Route de Chartres, 91440 Bures-sur-Yvette (France); Orlando, Domenico [LPTENS - UMR CNRS 8549,24, rue Lhomond, 75231 Paris (France); IPT Ph. Meyer,24, rue Lhomond, 75231 Paris (France); Reffert, Susanne [ITP - AEC, University of Bern,Sidlerstrasse 5, 3012 Bern (Switzerland)
2015-10-08
We engineer a brane picture for the reduction of Seiberg dualities from 4D to 3D, valid also in the presence of orientifold planes. We obtain effective 3D dualities on the circle by T-duality, geometrizing the non-perturbative superpotential which is an affine Toda potential. When reducing to pure 3D, we define a double-scaling limit which creates a sector of interacting singlets, giving a unified mechanism for the brane reduction of dualities.
Investigating the Use of Circle in Gear Cutting as a Substitute to Involute Profile
Directory of Open Access Journals (Sweden)
A.D. Kibet
2012-05-01
Full Text Available Gears are used in various machines and industries for transportation and transmission of power. Other uses are in consumer electronics and many machines used in homes like the washing machines, electric drills and kitchen appliances. Gears come in different sizes ranging from a module of 0.5 to 100 mm. Currently there is a problem of accurately machining gears. This is due to inaccurate positioning of the blank and cutter. The objective of the study was to investigate and determine the appropriate way of producing quality and accurate gears most economically through the use of a circle as a substitute to involute profile in gear cutting. Two different gears of same dimensional characteristics were cut; one using a Computer Numerical Control machine utilizing circle profile and the other using conventional milling machine. Dimensional comparisons were made of the two cut gears against an actual involute profile to determine the margin of error. The circle involute profile made using CNC was found to be exactly as the true involute profile though an error of 0.078 mm was observed in some sections of the profile. For the hobbing case, it was impossible to accurately machine the actual depth and as such, the intended depth of 7.32 was surpassed by 0.2 mm. The tooth was thicker throughout the length of the profile and the fillet radii lucked homogeneity. The involute circle approach was therefore successful and as such can benefit all CNC users and gear cutters in producing accurate gears cheaply.
INTEGRATING SIX-SIGMA AND HEALTHCARE QUALITY IMPROVEMENT CIRCLES IN REDUCING THE NEEDLE STICKING
Sen-Ji Chen; Frank F. C. Pan; Hsuen C. H. Chen
2008-01-01
Six-Sigma (SS) is a managerial philosophy used in detecting the error rate of a particular (set) of activities. This research applies six sigma concepts in dealing with troublesome needle-stick events that occurred in a Taiwan hospital. This research integrates several advanced managerial instruments into one framework, grounded in Continuous Quality Improvement and Total Quality Management. This framework combines Six-Sigma and Health Quality Improvement circle practices. The project suggest...
The Study of Transcendence Circles in Golshan-e Raz and Mafatih al-E’jaz
Directory of Open Access Journals (Sweden)
M Panahi
2014-03-01
Jungian attitude to the system of these circles leads to the discovery of their psychological aspect. The process of individuation is mapped onto the man’s revelation and he who has reached the center projects his progression on the system of being. Thus, the being also should move from individuation to center and experiences divine kindness and wrath via god’s glory and beauty manifestations.
Common Directions in Caucasian Chalk Circle and Keşanlı Ali Destanı
ODACI, Serdar
2016-01-01
Epic Theater founded by Bertolt Brecht influenced world literaturein the half of 20th century. Epic theater is against to Aristothalesian Theater.Naturally Brehct's plays were translated to Turkish and were presented. SuchTurkish writers as Haldun Taner and Vasıf Öngeren wrote play according toepic theater concept. In this paper common aspects in Keşanlı Ali Destanıand Caucasian Chalk Circle are examined.
"Common Directions in Caucasian Chalk Circle and Keşanlı Ali Destanı"
ODACI, Serdar
2010-01-01
Epic Theater founded by Bertolt Brecht influenced world literature in the half of 20th century. Epic theater is against to Aristothalesian Theater. Naturally Brehct's plays were translated to Turkish and were presented. Such Turkish writers as Haldun Taner and Vasıf Öngeren wrote play according to epic theater concept. In this paper common aspects in Keşanlı Ali Destanı and Caucasian Chalk Circle are examined.
Analysis of Laser Diode Pumped Solid-State Laser Resonator by the Transform Circle Approach
Institute of Scientific and Technical Information of China (English)
SONG Feng; ZHANG Guang-Yin; XU Jing-Jun; ZHANG Chao-Bo
2000-01-01
The typical laser characteristics of a laser diode pumped solid-state laser with a Z-type resonator structure are analyzed by the transform circle approach. Laser waists change with the thermal focus length of the lasing medium so that the output power becomes unstable. In particular, there is a very unstable operation region when the pump power is of medium magnitude. A method is put forward to avoid this situation.
Every timelike geodesic in anti--de Sitter spacetime is a circle of the same radius
Sokołowski, Leszek M
2016-01-01
We refine and analytically prove an old proposition due to Calabi and Markus on the shape of timelike geodesics of anti--de Sitter space in the ambient flat space. We prove that each timelike geodesic forms in the ambient space a circle of the radius determined by $\\Lambda$, lying on a Euclidean two--plane. Then we outline an alternative proof for $AdS_4$. We also make a comment on the shape of timelike geodesics in de Sitter space.
Planning Curvature-Constrained Paths to Multiple Goals Using Circle Sampling.
Lobaton, Edgar; Zhang, Jinghe; Patil, Sachin; Alterovitz, Ron
2011-01-01
We present a new sampling-based method for planning optimal, collision-free, curvature-constrained paths for nonholonomic robots to visit multiple goals in any order. Rather than sampling configurations as in standard sampling-based planners, we construct a roadmap by sampling circles of constant curvature and then generating feasible transitions between the sampled circles. We provide a closed-form formula for connecting the sampled circles in 2D and generalize the approach to 3D workspaces. We then formulate the multi-goal planning problem as finding a minimum directed Steiner tree over the roadmap. Since optimally solving the multi-goal planning problem requires exponential time, we propose greedy heuristics to efficiently compute a path that visits multiple goals. We apply the planner in the context of medical needle steering where the needle tip must reach multiple goals in soft tissue, a common requirement for clinical procedures such as biopsies, drug delivery, and brachytherapy cancer treatment. We demonstrate that our multi-goal planner significantly decreases tissue that must be cut when compared to sequential execution of single-goal plans.
Bu, Guochao; Wang, Pei
2016-04-01
Terrestrial laser scanning (TLS) has been used to extract accurate forest biophysical parameters for inventory purposes. The diameter at breast height (DBH) is a key parameter for individual trees because it has the potential for modeling the height, volume, biomass, and carbon sequestration potential of the tree based on empirical allometric scaling equations. In order to extract the DBH from the single-scan data of TLS automatically and accurately within a certain range, we proposed an adaptive circle-ellipse fitting method based on the point cloud transect. This proposed method can correct the error caused by the simple circle fitting method when a tree is slanted. A slanted tree was detected by the circle-ellipse fitting analysis, then the corresponding slant angle was found based on the ellipse fitting result. With this information, the DBH of the trees could be recalculated based on reslicing the point cloud data at breast height. Artificial stem data simulated by a cylindrical model of leaning trees and the scanning data acquired with the RIEGL VZ-400 were used to test the proposed adaptive fitting method. The results shown that the proposed method can detect the trees and accurately estimate the DBH for leaning trees.
Walker, Rachel; Henderson, Amanda; Cooke, Marie; Creedy, Debra
2011-05-01
Partnerships between university schools of nursing and health services lead to successful learning experiences for students and staff. A purposive sample of academics and students from a university school of nursing and clinicians from three health institutions involved in clinical learning (n=73) actively participated in a learning circles intervention conducted over 5 months in south east Queensland. Learning circle discussions resulted in enhanced communication and shared understanding regarding: (1) staff attitudes towards students, expectations and student assessment; (2) strategies enhancing preparation of students, mechanisms for greater support of and recognition of clinicians; (3) challenges faced by staff in the complex processes of leadership in clinical nursing education; (4) construction of learning, ideas for improving communication, networking and sharing; and (5) questioning routine practices that may not enhance student learning. Pre-post surveys of hospital staff (n=310) revealed significant differences across three sub-scales of 'accomplishment' (t=-3.98, pLearning circles can positively enhance organisational learning culture. The intervention enabled participants to recognise mutual goals. Further investigation around staff perception of their influence on their workplace is required. Copyright © 2010 Elsevier Ltd. All rights reserved.
White Blood Cell Segmentation by Circle Detection Using Electromagnetism-Like Optimization
Directory of Open Access Journals (Sweden)
Erik Cuevas
2013-01-01
Full Text Available Medical imaging is a relevant field of application of image processing algorithms. In particular, the analysis of white blood cell (WBC images has engaged researchers from fields of medicine and computer vision alike. Since WBCs can be approximated by a quasicircular form, a circular detector algorithm may be successfully applied. This paper presents an algorithm for the automatic detection of white blood cells embedded into complicated and cluttered smear images that considers the complete process as a circle detection problem. The approach is based on a nature-inspired technique called the electromagnetism-like optimization (EMO algorithm which is a heuristic method that follows electromagnetism principles for solving complex optimization problems. The proposed approach uses an objective function which measures the resemblance of a candidate circle to an actual WBC. Guided by the values of such objective function, the set of encoded candidate circles are evolved by using EMO, so that they can fit into the actual blood cells contained in the edge map of the image. Experimental results from blood cell images with a varying range of complexity are included to validate the efficiency of the proposed technique regarding detection, robustness, and stability.
White Blood Cell Segmentation by Circle Detection Using Electromagnetism-Like Optimization
Oliva, Diego; Díaz, Margarita; Zaldivar, Daniel; Pérez-Cisneros, Marco; Pajares, Gonzalo
2013-01-01
Medical imaging is a relevant field of application of image processing algorithms. In particular, the analysis of white blood cell (WBC) images has engaged researchers from fields of medicine and computer vision alike. Since WBCs can be approximated by a quasicircular form, a circular detector algorithm may be successfully applied. This paper presents an algorithm for the automatic detection of white blood cells embedded into complicated and cluttered smear images that considers the complete process as a circle detection problem. The approach is based on a nature-inspired technique called the electromagnetism-like optimization (EMO) algorithm which is a heuristic method that follows electromagnetism principles for solving complex optimization problems. The proposed approach uses an objective function which measures the resemblance of a candidate circle to an actual WBC. Guided by the values of such objective function, the set of encoded candidate circles are evolved by using EMO, so that they can fit into the actual blood cells contained in the edge map of the image. Experimental results from blood cell images with a varying range of complexity are included to validate the efficiency of the proposed technique regarding detection, robustness, and stability. PMID:23476713
Concentric circles based simple optical landing aid for vertical takeoff and landing aircrafts
Murshid, Syed H.; Enaya, Rayan; Lovell, Gregory L.
2014-09-01
Vertical takeoff and landing (VTOL) aircrafts such as helicopters and drones, add a flexible degree of operation to airborne vehicles. In order to operate these devices in low light situations, where it is difficult to determine slope of the landing surface, a lightweight and standalone device is proposed here. This small optical device can be easily integrated into current VTOL systems. An optical projector consisting of low power, light weight, solid state laser along with minimal optics is utilized to illuminate the landing surface with donut shaped circles and coaxial centralized dot. This device can placed anywhere on the aircraft and a properly placed fiber system can be used to illuminate the surface beneath the bottom of the VTOL aircraft in a fashion that during operation, when the aircraft is parallel to the landing surface, the radius between the central dot and outer ring(s) are equidistant for the entire circumference; however, when there the landing surface of the VTOL aircraft is not parallel to the landing strip, the radial distance between two opposite sides of the circle and central dot will be unequal. The larger this distortion, the greater the difference will be between the opposite sides of the circle. Visual confirmation or other optical devices can be used to determine relative alignment of the projector output allowing the pilot to make proper adjustments as they approach the landing surface to ensure safe landings. Simulated and experimental results from a prototype optical projector are presented here.
Linear Determination of a Camera's Intrinsic Parameters Using Two Intersecting Circles
Directory of Open Access Journals (Sweden)
Xu Chen
2014-03-01
Full Text Available An approach using two intersecting circles is proposed as a linear approach for determining a camera's intrinsic parameters. The two intersecting coplanar circles have four intersection points in the projective plane: two real points and two circular points. In the image plane, the diagonal triangle - on which the image of the four intersection points composes a complete quadrangle - is a self-polar triangle for the projection curves of the circles. The vertex of the self-polar triangle is the null space of the degenerate conic formed by the image of the four intersection points. By solving the three vertices of the self-polar triangle using the image coordinates of the two real intersection points, the degenerate conic can be obtained. The image of the two circular points is then computed from the intersection points of the degenerate conic. Using the image of the circular points from the three images of the same planar pattern with different directions, the intrinsic parameters can be linearly determined.
The Obstruction criterion for non existence of Invariant Circles and Renormalization.
De la Llave, R
2003-01-01
We formulate a conjecture which supplements the standard renormalization scenario for the breakdown of golden circle in twist maps. We show rigorously that if the conjecture was true then: a) The stable manifold of the non-trivial fixed point would indeed be a boundary between the existence of smooth invariant tori and hyperbolic orbits with golden mean rotation number. In particular, the boundary of the set of twist maps with a torus with a golden mean rotation number would include a smooth submanifold in the space of analytic mappings. b) The obstruction criterion of [Olvera-Simo] would be sharp in the universality class of the renormalization group. c) The criterion of [Greene-79] for existence of invariant circles if and only if there the residues of approximating orbits are finite would be valid for maps in the universality class. d) If there is no invariant circle, there are hyperbolic sets with golden mean rotation number. We also provide numerical evidence which suggests that the conjecture is true an...
Aketagawa, M.; Madden, M.; Uesugi, S.; Kumagai, T.; Maeda, Y.; Okuyama, E.
2012-11-01
In the conventional methods to measure radial, axial and angular motions of spindles, complicated artifacts with relative large volume (such as two balls linked with a cylinder) are required. Small volume artifact is favorable from the viewpoint of the accurate and practical measurement of the spindle motion. This paper describes a concurrent measurement of spindle radial, axial and angular motions using concentric circle grating and phase modulation interferometers. In the measurement, the concentric circle grating with fine pitch is installed on top of the spindle of interest. The grating is a reference artifact in the method. Three optical sensors are fixed over the concentric circle grating, and observe the proper positions of the grating. The optical sensor consists of a frequency modulated laser diode as a light source, and two interferometers. One interferometer observes an interference fringe between reflected light form a fixed mirror and 0-th order diffraction light from the grating to measure the axial motion. Another interferometer observes an interference fringe between +/-2nd diffraction lights from the grating to measure the radial motion. Using three optical sensors, three radial displacements and three axial displacements of the proper observed position of the grating can be measured. From these measured displacements, radial, axial and angular motions of the spindle can be calculated concurrently. In the paper, a measurement instrument, a novel fringe interpolation technique by sinusoidal phase modulation and experimental results are discussed.
The Archaeoastronomy of Tomnaverie Recumbent Stone Circle: A Comparison of Methodologies
Directory of Open Access Journals (Sweden)
Liz Henty
2014-09-01
Full Text Available The way we view the past is constantly modified by new evidence and methodological advances. Archaeological data is gleaned from the ground and archaeoastronomical evidence considers the use of the sky in relation to the archaeological record. Since the beginning of the 20th century the two disciplines of archaeology and archaeoastronomy have flirted with one another but there has never been a satisfactory marriage. This paper looks at the Recumbent Stone Circles (RSCs of north-east Scotland to examine the methodologies, and compare the results, of both disciplines. The RSCs are a distinctive type of stone circle characterised by a large recumbent stone which is flanked on either side by a tall pillar. This recumbent arrangement is almost invariably located in the south-west of the circle. RSCs are generally located near the summits of low hills and enjoy clear horizon views. Over the years they have been the subject of extensive research. This research will be reviewed and Tomnaverie RSC will be singled out as a special case study to examine whether there still needs to be a divide between the disciplines.
Numerical simulation of the blood flow behavior in the circle of Willis
Directory of Open Access Journals (Sweden)
Razavi Seyyed Esmail
2014-06-01
Full Text Available Introduction: This paper represents the numerical simulation of blood flow in the circle of Willis (CoW. Circle of Willis is responsible for the oxygenated blood distribution into the cerebral mass. To investigate the blood behavior, two Newtonian and non-Newtonian viscosity models were considered and the results were compared under steady state conditions. Methods: Methodologically, the arterial geometry was obtained using 3D magnetic resonance angiography (MRA data. The blood flow through the cerebral vasculature was considered to be steady and laminar, and the Galerkin’s finite element method was applied to solve the systems of non-linear Navier-Stokes equations. Results: Flow patterns including flow rates and shear rates were obtained through the simulation. The minimal magnitude of shear rates was much greater than 100 s-1 through the larger arteries; thus, the non-Newtonian blood viscosity tended to approach the constant limit of infinite shear viscosity through the CoW. So, in larger arteries the non-Newtonian nature of blood was less dominant and it would be treated as a Newtonian fluid. The only exception was the anterior communicating artery (ACoA in which the blood flow showed different behavior for the Newtonian and non-Newtonian cases. Conclusion: By comparing the results it was concluded that the Newtonian viscosity assumption of blood flow through the healthy, complete circle of Willis under the normal and steady conditions would be acceptably accurate.
Centripetal and centrifugal forces in the moral circle: Competing constraints on moral learning.
Graham, Jesse; Waytz, Adam; Meindl, Peter; Iyer, Ravi; Young, Liane
2017-10-01
The idea of the moral circle pictures the self in the center, surrounded by concentric circles encompassing increasingly distant possible targets of moral concern, including family, local community, nation, all humans, all mammals, all living things including plants, and all things including inanimate objects. The authors develop the idea of two opposing forces in people's moral circles, with centripetal forces pulling inward, urging greater concern for close others than for distant others, and centrifugal forces pushing outward, resisting "drawing the line" anywhere as a form of prejudice and urging egalitarian concern for all regardless of social distance. Review of the developmental literature shows very early emergence of both moral forces, suggesting at least partly intuitive bases for each. Moral education approaches favoring one force over the other are compared, to show how these forces can provide constraints on moral learning. Finally, the centripetal/centrifugal forces view is applied to current moral debates about empathy and about politics. The authors argue that this view helps us see how intercultural and interpersonal disagreements about morality are based in intrapersonal conflicts shared by all people. Copyright © 2016. Published by Elsevier B.V.
Linear Determination of a Camera's Intrinsic Parameters Using Two Intersecting Circles
Directory of Open Access Journals (Sweden)
Xu Chen
2014-03-01
Full Text Available An approach using two intersecting circles is proposed as a linear approach for determining a camera's intrinsic parameters. The two intersecting coplanar circles have four intersection points in the projective plane: two real points and two circular points. In the image plane, the diagonal triangle - on which the image of the four intersection points composes a complete quadrangle - is a self-polar triangle for the projection curves of the circles. The vertex of the self-polar triangle is the null space of the degenerate conic formed by the image of the four intersection points. By solving the three vertices of the self-polar triangle using the image coordinates of the two real intersection points, the degenerate conic can be obtained. The image of the two circular points is then computed from the intersection points of the degenerate conic. Using the image of the circular points from the three images of the same planar pattern with different directions, the intrinsic parameters can be linearly determined.
Design of Circle Array Pattern for Transparent Nanomesh-Type Electrodes.
Shin, Seungsu; Ganorkar, Shraddha; Kim, Jungyoon; Kim, Young-Hwan; Kim, Yong Tae; Kim, Seong-Il
2015-10-01
In this study, we report simulation results for the optical properties of nanomesh-type electrodes for transparent electrode. Usually, indium tin oxide (ITO) is commonly used for transparent conductor to solar cell, display, LED and other electronic modules. However, the cost is high due to the rarity of indium. An alternative way is use of transparent nanomesh-type metal electrode for solar cell. Finite different time domain (FDTD) method was used to simulate and analyze their optical properties. Various array patterns (square, circle and circle hexagonal array) of metal on glass (SiO2) substrates were designed and their properties of transmission and reflection were simulated by using the broad band (λ = 300~1200 nm) plane wave source. To compare basic characteristics of each pattern, various structural parameters such as hole diameter, pitch and metal thickness were applied. The effect of three typical metals, such as Ag, Au, and Al was also compared. In the results, we will discuss about large dip of transmission appeared at the particular wavelength region from the circle array pattern, which is design with pitch of 500 nm at the wavelength range 700 to 800 nm. The surface plasmonpolaritons (SPP) effect can be the cause of large dip and we could find a broad and high transmission from the properly designed in nanomesh-type electrodes, which was calculated as a function of wavelength.
Institute of Scientific and Technical Information of China (English)
Li Chen; Cheng Shengkui; Chen Yuansheng; Zhang Yingqiu
2006-01-01
Chengde City, famous for its cultural sightseeing tourism industry, and is located in China's "Capital Holiday Tourism Circle". This location is advantageous, because of the recent boom in China's national tourism industry. This industry has gone through several structural and development changes with in the past several years. A result of these restructuring patterns is the great changes concerning competitive and cooperative relations among tourism destinations, which have precipitated the decline of the traditional sightseeing pattern.Northern China's "Capital Holiday Tourism Circle" is one of nine key areas within the Chinese tourism industry under development during the Eleventh Five-Year Plan. In the present article the method of "Distance Decline of The Tourist Flow" was used to define the flow of tourists in the Capital Holiday Tourism Circle and its influence upon Chengde's tourism spatial distribution. 3 aspects will be discussed: (1) The transformation from sightseeing to leisure markets makes the change possible in Chengde's tourism spatial pattern. (2) The location advantage (adjacent to Beijing and Tianjin) also leads to the change in Chengde tourism spatial pattern. (3) The establishment of freeways also contributes to a great degrees of change.The rapid development of leisure tourism might lead to the change from nucleus model to a diversified one within Chengde's tourism. Specifically, Chengde is developing the tourism industry with the central heritage area as the nucleus and the northern forest,pasture,southern mountain, and rivers as its periphery.
Beard, Ella King
2016-01-01
This study investigates the role of the circle dance in decreasing depressed affect amongst a group of 45 patients with severe mental health illnesses and highlights the most significant aspect of that dance. Patients participated in one of four conditions: a group performing a regular traditional upbeat Irish circle dance holding hands and with a jump step [jump+hands]; a group performing the same dance holding hands with no jump step [hands]; a group performing the same dance without holdin...
DEFF Research Database (Denmark)
Morace, Renata Erica; Hansen, Hans Nørgaard; De Chiffre, Leonardo
2005-01-01
This paper deals with the uncertainty estimation of measurements performed on optical coordinate measuring machines (CMMs). Two different methods were used to assess the uncertainty of circle diameter measurements using an optical CMM: the sensitivity analysis developing an uncertainty budget...
Song, Weiling; Zhang, Qiao; Sun, Wenbo
2015-02-11
An ultrasensitive protocol for fluorescent detection of DNA is designed by combining the template enhanced hybridization process (TEHP) with Rolling Circle Amplification (RCA) and Catalytic Hairpin Assembly (CHA), showing a remarkable amplification efficiency.
National Research Council Canada - National Science Library
Matsui, Mary S; Schalka, Sérgio; Vanderover, Garrett; Fthenakis, Christina G; Christopher, J; Bombarda, Patricia Camarano Pinto; Bueno, Juliana Regina; Viscomi, Bianca Lenci Inácio; Bombarda Júnior, Mário Sérgio
2015-01-01
AbstractBACKGROUND:Peri-orbital dark circles are a cosmetic concern worldwide, and have been attributed to hyperpigmentation from allergy or atopic dermatitis, blood stasis, structural shadowing effects, and a thin...
Stino, Zandra H.; Palmer, Barbara C.
1998-01-01
Over 18 weeks, nine female offenders worked in a collaborative learning circle with process-based writing (prewriting, drafting, sharing, revising, editing, proofreading, publishing). Most showed a significant increase in self-esteem. (SK)
Kobayashi's and Teichmüller's Metrics on the Teichmüller Space of Symmetric Circle Homeomorphisms
Institute of Scientific and Technical Information of China (English)
Jun HU; Yun Ping JIANG; Zhe WANG
2011-01-01
We give a direct proof of a result of Earle, Gardiner and Lakic, that is, Kobayashi's metric and Teichmüller's metric coincide with each other on the Teichmüller space of symmetric circle homeomorphisms.
"Really," "Not Possible," "I Can't Believe It": Exploring Informational Text in Literature Circles
Barone, Diane; Barone, Rebecca
2016-01-01
Fifth graders' interpretations of nonfiction or informational text were explored. Each literature circle group read and responded to informational text. Discoveries included that students' conversations and written responses were closely connected to text and that students created multimodal responses.
Institute of Scientific and Technical Information of China (English)
马亮; 郭进; 陈光伟; 郭瑞
2015-01-01
为了提高动态配流模型的通用性和稳定性，基于约束程序累积调度和字典序多目标优化，以作业之间实施逻辑和优先级关系、班计划和列车编组计划要求、资源容量限制等为约束，按照配流成功的出发列车优先级总和最大、车辆平均中停时最小和资源利用率最高3个目标的优先级，建立适应于不同解体方式的动态配流字典序多目标累积调度的3层模型。为提高算法效率，设计了约束传播和多点构建性搜索混合的带初始解迭代算法，每层先通过约束传播算法化简模型，再通过带约束传播的多点构建性搜索算法快速求解，以决策出优化的作业排程和配流方案。实验表明，模型扩展性更强、更稳定、更符合现场实际；算法效率高，能够满足现场对计划编制和调整的实施性需求。%To improve the versatility and stability of the dynamic wagon-flow allocation model,the dynamic wagon-flow allocation lexicographic multi-objective cumulative scheduling model is set up to maximize the sum of priority of the departure trains,minimize the average residence time of the cars,and maximize the resource utilization,based on the theory of constraint programming cumulative scheduling and lexicographic multi-objective optimization.In this model,the precedence and logical relationship among traffic jobs,the demands of the train shift plan and the train formation plan,and the capacity limit of the resources are all taken into account as constraints.The model is then be adapted for different disassembly modes and is divided into three sub-layers,according to the lexicographic or-der of the three objectives.Then,the optimized schemes of job scheduling and wagon-flow allocation are received by solving the model iteratively,using the hybrid algorithm of constraint propagation and multi-point constructive search.In each sub-layer,the search space is initially reduced by constraint
Directory of Open Access Journals (Sweden)
David A. Becker
2012-11-01
Full Text Available A bilaterally symmetrical convex dodecahedron consisting of twelve quadrilateral faces is derived from the icosahedron via a process akin to Fuller’s Jitterbug Transformation. The unusual zygomorphic dodecahedron so obtained is shown to harbor a bilaterally symmetrical jazz/blues harmonic code on its twelve faces that is related to such fundamental music theoretical constructs as the Circle of Fifths and Euler’s tonnetz. Curiously, the patterning within the aforementioned zygo-dodecahedron is discernibly similar to that observed in a ventral view of the human brain. Moreover, this same pattern is arguably evident during development of the embryonic pharynx. A possible role for the featured zygo-dodecahedron in cephalogenesis is considered. Recent studies concerning type II cadherins, an important class of proteins that promote cell adhesion, have generated data that is demonstrated to conform to this zygo-dodecahedral brain model in a substantially congruous manner.
Directory of Open Access Journals (Sweden)
Abbas Monfared
2014-11-01
Full Text Available In a globalized era where English keeps the position of an international language, learnt and spoken by lots of people from diverse linguistic, cultural and national backgrounds, there is a need for a new perspective towards English as an international language which can bridge notions and cultures. The appearance of varieties of English is the consequence of the global dissemination of English. Based on a combination of quantitative and qualitative data using a semi-structured questionnaire (see Appendix A administered to 60 Iranian learners from expanding circle and 60 Indian learners from outer circle, this study surveyed the developing picture of EIL pronunciation and evaluation of different varieties of English from the perspective of learners from two circles which include the most users of English in the globalized world. The results of the questionnaires supplemented by interviews with leaners from expanding and outer circles revealed that expanding-circle learners like more to have a native-like identity with their preference towards nativism. The implications on the findings on the spread of native speaker norms and the status of ELF and its reflections in learning and teaching in expanding and outer circle countries are discussed. Keywords: Pronunciation, Intelligibility, English as an International language, Language Awareness, Identity
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
Foster care is conducive to giving orphaned children a better life For most children living in orphanages, having a real home is just a pipe dream. Although they may be well looked after, receive a good education and proper nutrition, the love and care that come from being part of a real family just aren't there.
1990-04-09
spread rapidly through many major Japanese firms. In 1962, Dr. Kaoru Ishikawa tied these new quality control methods to the theories of Maslow , Herzberg...should be on people solving problems and not on hierarchical pyramids of paperwork. 21 6. Management must learn how to positively reinforce participative
Institute of Scientific and Technical Information of China (English)
黎浩东; 何世伟; 景云; 王烁
2012-01-01
基于阶段计划列车解编顺序优化,同时考虑出发列车牵引质量及换长两个满轴约束,以车流接续与分配的“代价”最小为目标,构建编组站配流优化0-1整数规划模型,并设计与ILOG优化软件结合的和声搜索算法进行求解.其中配流结果使用ILOG求解,列车解编顺序则采用和声搜索策略进行优化.在构造新的和声过程中,采用邻域搜索策略提升算法的寻优效率.算例结果表明:提出的方法能获取鲁棒性更高的配流方案.%Taking into account the size limitations of both weight and length of departure trains, and the breakup sequence of inbound trains and make-up sequence of outbound trains, the 0-1 integer programming model for optimization of wagon-flow allocation at marshaling stations was established. The objective of this model was set to minimize the total costs of cars assignment. Then the hybrid heuristic algorithm based on the harmony search strategy and ILOG was designed to solve the model. The harmony search strategy was used to optimize the break-up sequence of inbound trains and make-up sequence of outbound trains, and cars assignment for harmonic evaluation was solved by ILOG. The neighborhood search strategy was used to enhance the convergence rate of the algorithm in the process of constructing the new harmony. The result of a numerical example proves that the proposed model and algorithm can provide a wagon-flow allocation scheme of higher robustness.
Directory of Open Access Journals (Sweden)
John Robert Schmitz
Full Text Available This paper examines the pioneering model of World Englishes formulated by Kachru in the early 1980s that allocates the presence of English into three concentric circles: first of all, the inner circle (Great Britain, the USA where the language functions as an L1 (or native language; secondly, the outer circle (India, Nigeria where the language was forced upon the subjugated people by Britain; thirdly, the expanding circle (China, Brazil where English is studied as a foreign language. Researchers in the area of language studies tend to put too much store in Kachru's model expecting it to expose the different circles: (i the proficiency level of the speakers, (ii the variation that exists in the different dialects of the language, and (iii how the many users appropriate the language to perform their daily routine. Pung (2009 suggests "going beyond" the three circle model with his proposal of a Conical Model of English (CME, while Park and Wee (2009, p.402 state that models have no "magical efficacy in challenging dominant ideologies of English" and that change in the world is not brought about by models but my people. Based on Park and Lee's caution with regard to models, and in lieu of Pung's "going beyond" the well-known Kachruvian model, the thrust of this article is to look specifically under the inner circle, that is, the supposed "native speaker domain". It will be argued in this paper that the circles function as a palimpsest erasing and ignoring what happened in the past linguistically, historically and culturally before the appearance of English in the spaces that the language occupies at the present time in the inner, outer, and expanding circles. An examination of days gone-by, with a focus on Kachru's inner circle, can present a mirror to examine: (i bilingual (multilingual biases, (ii migration of peoples and treatment of immigrants, (iii respect (or lack of for the linguistic and cultural rights of minorities, and (iv the hegemony of
PySCIs: a user friendly Python tool to quickly applying Small Circle methods
Calvín, Pablo; José Villalaín, Juan; Casas, Antonio; Torres, Sara
2017-04-01
Small Circle (SC) methods are common tools in paleomagnetic working on synfolding paleomagnetic components. These methods have a twofold applicability. On one hand, the Small Circle Intersection (SCI) method allows obtaining the local remagnetization direction and on the other the SCs can be used to restitute the attitude of the sedimentary beds at the moment of the remagnetization acquisition. The bases of the SCI method are as follows. (i) The paleomagnetic direction for each site follows a path which draws a SC under progressive untinting of the beds; this SC links the paleomagnetic direction before and after the tectonic correction. (ii) Considering that the beds have been deformed only by tilting around the bedding strike, the remagnetization direction is placed upon the small circle of each site. (iii) The acquisition of the remagnetization was simultaneous for the analyzed rocks. Therefore, the remagnetization direction must to be placed upon the small circle for all sites and hence the all small circle must to intersect in one direction which corresponds with the remagnetization direction. Actually the method looks for the direction in the space closest to the set of SCs by means of A/n parameter (this is the sum of the angular distances between one direction and each SC normalized by the number of sites). Once the remagnetization direction is known, it is possible to calculate the paleomagnetic direction upon each SC closest to the calculated remagnetization direction, called as Best Fit Direction (BFD). After that the paleodip of the bed (i.e. the dip of the bed at the moment of the remagnetization event) can be calculated for each site (the paleodip is the angle measured over the SC between the BFD and the paleomagnetic direction after the complete bedding correction) and perform a palinspastic reconstruction of a region. We present pySCIs, a new python tool which allows applying this methodology in an easy way. The program has two different modules, py
High accuracy genotyping directly from genomic DNA using a rolling circle amplification based assay
Directory of Open Access Journals (Sweden)
Du Yuefen
2003-05-01
Full Text Available Abstract Background Rolling circle amplification of ligated probes is a simple and sensitive means for genotyping directly from genomic DNA. SNPs and mutations are interrogated with open circle probes (OCP that can be circularized by DNA ligase when the probe matches the genotype. An amplified detection signal is generated by exponential rolling circle amplification (ERCA of the circularized probe. The low cost and scalability of ligation/ERCA genotyping makes it ideally suited for automated, high throughput methods. Results A retrospective study using human genomic DNA samples of known genotype was performed for four different clinically relevant mutations: Factor V Leiden, Factor II prothrombin, and two hemochromatosis mutations, C282Y and H63D. Greater than 99% accuracy was obtained genotyping genomic DNA samples from hundreds of different individuals. The combined process of ligation/ERCA was performed in a single tube and produced fluorescent signal directly from genomic DNA in less than an hour. In each assay, the probes for both normal and mutant alleles were combined in a single reaction. Multiple ERCA primers combined with a quenched-peptide nucleic acid (Q-PNA fluorescent detection system greatly accellerated the appearance of signal. Probes designed with hairpin structures reduced misamplification. Genotyping accuracy was identical from either purified genomic DNA or genomic DNA generated using whole genome amplification (WGA. Fluorescent signal output was measured in real time and as an end point. Conclusions Combining the optimal elements for ligation/ERCA genotyping has resulted in a highly accurate single tube assay for genotyping directly from genomic DNA samples. Accuracy exceeded 99 % for four probe sets targeting clinically relevant mutations. No genotypes were called incorrectly using either genomic DNA or whole genome amplified sample.
Uniform circular motion concept attainment through circle share learning model using real media
Ponimin; Suparmi; Sarwanto; Sunarno, W.
2017-01-01
Uniform circular motion is an important concept and has many applications in life. Student’s concept understanding of uniform circular motion is not optimal because the teaching learning is not carried out properly in accordance with the characteristics of the concept. To improve student learning outcomes required better teaching learning which is match with the characteristics of uniform circular motion. The purpose of the study is to determine the effect of real media and circle share model to the understanding of the uniform circular motion concept. The real media was used to visualize of uniform circular motion concept. The real media consists of toy car, round table and spring balance. Circle share model is a learning model through discussion sequentially and programmed. Each group must evaluate the worksheets of another group in a circular position. The first group evaluates worksheets the second group, the second group evaluates worksheets third group, and the end group evaluates the worksheets of the first group. Assessment of learning outcomes includes experiment worksheets and post-test of students. Based on data analysis we obtained some findings. First, students can explain the understanding of uniform circular motion whose angular velocity and speed is constant correctly. Second, students can distinguish the angular velocity and linear velocity correctly. Third, students can explain the direction of the linear velocity vector and the direction of the centripetal force vector. Fourth, the student can explain the influence of the mass, radius, and velocity toward the centripetal force. Fifth, students can explain the principle of combined of wheels. Sixth, teaching learning used circle share, can increase student activity, experimental results and efficiency of discussion time.
An innovative integrated oxidation ditch with vertical circle(IODVC) for wastewater treatment
Institute of Scientific and Technical Information of China (English)
XIA Shi-bin; LIU Jun-xin
2004-01-01
The oxidation ditch process is economic and efficient for wastewater treatment, but its application is limited in case where land is costly due to its large land area required. An innovative integrated oxidation ditch with vertical circle(IODVC) system was developed to treat domestic and industrial wastewater aiming to save land area. The new system consists of a single-channel divided into two ditches(the top one and the bottom one by a plate), a Kesner type brush, and an innovative integral clarifier. Different from the horizontal circle of the conventional oxidation ditch, the flow of IODVC system recycles from the top zone to the bottom zone in the vertical circle as the brush is running, and then the IODVC saved land area required by about 50% compared with a conventional oxidation ditch with an intrachannel clarifier. The innovative integral clarifier is effective for separation of liquid and solids, and is preferably positioned at the opposite end of the brush in the ditch. It does not affect the hydrodynamic characteristics of the mixed liquor in the ditch, and the sludge can automatically return to the down ditch without any pump. In this study, experiments of domestic and dye wastewater treatment were carried out in bench scale and in full scale, respectively. Results clearly showed that the IODVC efficiently removed pollutants in the wastewaters, i.e., the average of COD removals for domestic and dye wastewater treatment were 95% and 90%, respectively, and that the IODVC process may provide a cost effective way for full scale dye wastewater treatment.
Local Circles in a Circular Economy – the Case of Smartphone Repair in Denmark
Directory of Open Access Journals (Sweden)
Henrik Riisgaard
2016-02-01
Full Text Available Abstract Circular economy has gained increasing attention the last decade, and more often the main focus is on the large global circles addressing recycling of materials rather than the “inner circles” that address maintenance/repair and reuse. In this article we investigate one such inner circle ofthe circular economy namely repair of smartphones which extends the lifetime of products and adds to a local economy. Local repair of smartphones has increased in the resent years in Denmark. These loop-closing businesses not only extend the useful lifetime of smartphones; they also entail both environmental benefits and economic value creation. We map the extent ofthe repair sector and investigate the drivers and barriers for its emergence. The study builds on desk studies for identification of repair companiesand telephone interviews with 33 out of 90 identified companies. The mapping of the businessesshows that the repair of smartphones constitute viable business opportunities, and that the main driversarerelated to the economic business potentials as well as motivated entrepreneurs who spot a market potential.The study concludes that the local circular economy within smartphone repair is due to large consumer willingness-to-pay for repair and maintenance services, and this can extend the lifetime of the smartphones. There are some special characteristics that limit the possibility to apply the results directly to other product groups, but further analysis of how to facilitate repair shops within other product groups are interesting in order to facilitate the development of local circles in a circular economy not only in Denmark but also in other countries. Keywords: Circular economy; Smartphone;Repair; Remanufacturing.
Two-photon microscopy with double-circle trajectories for in vivo cerebral blood flow measurements
Landolt, Andrin; Obrist, Dominik; Wyss, Matthias; Barrett, Matthew; Langer, Dominik; Jolivet, Renaud; Soltysinski, Tomasz; Roesgen, Thomas; Weber, Bruno
2013-05-01
Scanning microscopes normally use trajectories which produce full-frame images of an object at a low frame rate. Time-resolved measurements are possible if scans along a single line are repeated at a high rate. In conjunction with fluorescence labeling techniques, in vivo recording of blood flow in single capillaries is possible. The present work investigates scanning with double-circle trajectories to measure blood flow simultaneously in several vessels of a capillary network. With the trajectory centered near a bifurcation, a double circle crosses each vessel twice, creating a sensing gate for passing dark red blood cells in fluorescently labeled plasma. From the stack of scans repeated at 1,300 Hz, the time-resolved velocity is retrieved using an image correlation approach. Single bifurcation events can be identified from a few fluorescently labeled red blood cells. The applicability of the method for in vivo measurements is illustrated on the basis of two-photon laser scanning microscopy of the cerebral capillary network of mice. Its performance is assessed with synthetic data generated from a two-phase model for the perfusion in a capillary network. The calculation of velocities is found to be sufficiently robust for a wide range of conditions. The achievable limits depend significantly on the experimental conditions and are estimated to be in the 1 μm/s (velocity) and 0.1 s (time resolution) ranges, respectively. Some manual fine-tuning is required for optimal performance in terms of accuracy and time resolution. Further work may lead to improved reliability with which bifurcation events are identified in the algorithm and to include red blood cell flux and hematocrit measurements. With the capability for time-resolved measurements in all vessels of a bifurcation, double-circle scanning trajectories allow a detailed study of the dynamics in vascular networks.
Directory of Open Access Journals (Sweden)
Bernard-Champmartin Aude
2013-01-01
Full Text Available In a prior work [CEMRACS10], a curvilinear bi-dimensional finite volume extension of Lagrangian centered schemes GLACE [GLACE] on unstructured cells, whose edges are parameterized by rational quadratic Bézier curves was proposed and we showed numerical results for this scheme. Now, we extend the EUCCLHYD scheme [EUCCLHYD] to these cells. To simulate flows with evolving large deformations, we write a formalism allowing the time evolution of the conic parameter. As an example, this allows an edge changing from an ellipse segment to a hyperbolic one. In this framework, we consider the case of a mesh whose edges are circle segments with non fixed centers. We show that this formalism extends also the previous work [GLACE CIRCLE] (which is equivalent to [CEMRACS10] when conic edges are all circles. This is a necessary first step toward general conical deformation. Dans un travail précédent [CEMRACS10], une extension volume fini bi-dimensionnelle curviligne du schéma Lagrangien centré GLACE [GLACE] sur des cellules non structurées dont les bords sont paramétrés par des courbes de Bézier quadratiques rationnelles a été proposée. Maintenant, nous proposons une extension du schéma EUCCLHYD [EUCCLHYD] à ce type de cellules et pour lequel nous montrons quelques résultats numériques. Pour pouvoir suivre un écoulement subissant de grandes variations de forme, nous écrivons un formalisme qui permet l’évolution en temps du paramètre de chaque conique. Ainsi, un bord de maille peut d’un segment d’ellipse devenir en cours de calcul un segment d’hyperbole. Dans ce cadre, nous considérons le cas particulier d’un maillage dont les bords de cellules sont des arcs de cercle avec des centres non fixes. Nous montrons que ce formalisme constitue également une extension directe d’un travail précédent [GLACE CIRCLE] (qui équivaut à [CEMRACS10] dans le cas où les bords coniques sont tous des cercles. Ce résultat constitue une
Assunção, Matthias Röhrig
2014-01-01
The emergence of the modern styles of capoeira should be considered in the global context of the modernization of martial arts currently in progress in Europe and Asia on the one hand, and the new phase of Afro-descendant modernity on the other. The confrontation between the capoeira, jiu-jitsu and other martial arts circles led mestre Bimba to develop his regional Bahian fighting style. The revival of traditional capoeira as Angolan capoeira led by mestre Pastinha is part of the broader movement of affirmation of Afro-Bahian culture in Salvador and the growing visibility of the Afro-descendant body in the Atlantic world.
NanoCluster Beacons as reporter probes in rolling circle enhanced enzyme activity detection
Juul, Sissel; Obliosca, Judy M.; Liu, Cong; Liu, Yen-Liang; Chen, Yu-An; Imphean, Darren M.; Knudsen, Birgitta R.; Ho, Yi-Ping; Leong, Kam W.; Yeh, Hsin-Chih
2015-04-01
As a newly developed assay for the detection of endogenous enzyme activity at the single-catalytic-event level, Rolling Circle Enhanced Enzyme Activity Detection (REEAD) has been used to measure enzyme activity in both single human cells and malaria-causing parasites, Plasmodium sp. Current REEAD assays rely on organic dye-tagged linear DNA probes to report the rolling circle amplification products (RCPs), the cost of which may hinder the widespread use of REEAD. Here we show that a new class of activatable probes, NanoCluster Beacons (NCBs), can simplify the REEAD assays. Easily prepared without any need for purification and capable of large fluorescence enhancement upon hybridization, NCBs are cost-effective and sensitive. Compared to conventional fluorescent probes, NCBs are also more photostable. As demonstrated in reporting the human topoisomerases I (hTopI) cleavage-ligation reaction, the proposed NCBs suggest a read-out format attractive for future REEAD-based diagnostics.As a newly developed assay for the detection of endogenous enzyme activity at the single-catalytic-event level, Rolling Circle Enhanced Enzyme Activity Detection (REEAD) has been used to measure enzyme activity in both single human cells and malaria-causing parasites, Plasmodium sp. Current REEAD assays rely on organic dye-tagged linear DNA probes to report the rolling circle amplification products (RCPs), the cost of which may hinder the widespread use of REEAD. Here we show that a new class of activatable probes, NanoCluster Beacons (NCBs), can simplify the REEAD assays. Easily prepared without any need for purification and capable of large fluorescence enhancement upon hybridization, NCBs are cost-effective and sensitive. Compared to conventional fluorescent probes, NCBs are also more photostable. As demonstrated in reporting the human topoisomerases I (hTopI) cleavage-ligation reaction, the proposed NCBs suggest a read-out format attractive for future REEAD-based diagnostics. Electronic
LONG-TIME ASYMPTOTIC FOR THE DAMPED BOUSSINESQ EQUATION IN A CIRCLE
Institute of Scientific and Technical Information of China (English)
Zhang Yi; Lin Qun; Lai Shaoyong
2005-01-01
The first initial-boundary value problem for the following equation utt - a△utt - 2b△ut = α△3u - β△2u + △u + γ△(u2) in a unit circle is considered. The existence of strong solution is established in the space Co([0, ∞), HST(0, 1)), s ＜ 7/2, and the solutions are constructed in the form of series in the small parameter present in the initial conditions. For 5/2 ＜ s ＜ 7/2, the uniqueness is proved. The long-time asymptotics is obtained in the explicit form.
Renormalization and 3-manifolds which fiber over the circle (AM-142)
McMullen, Curtis T
2014-01-01
Many parallels between complex dynamics and hyperbolic geometry have emerged in the past decade. Building on work of Sullivan and Thurston, this book gives a unified treatment of the construction of fixed-points for renormalization and the construction of hyperbolic 3- manifolds fibering over the circle. Both subjects are studied via geometric limits and rigidity. This approach shows open hyperbolic manifolds are inflexible, and yields quantitative counterparts to Mostow rigidity. In complex dynamics, it motivates the construction of towers of quadratic-like maps, and leads to a quantitativ
[From Comte to Carnap. Marcel Boll and the introduction of the Vienna Circle in France].
Schöttler, Peter
2015-01-01
The issue of the introduction of viennese "scientific philosophy" in France appears to be resolved. However, the rediscovery of the positivist physicist Marcel Boll (1886-1971), who was the first-well before Louis Rougier-to draw the French public's attention to the works of Schlick, Frank, and Carnap, obliges us to rethink the passage from traditional positivism to neo-positivism during the 1920s and 1930s. The French reception of the Vienna circle can be dated earlier than accepted and is more profound than usualy assumed.
Case report: Dot-in-circle sign - An MRI and USG sign for "Madura foot"
Directory of Open Access Journals (Sweden)
Anitha Sen
2011-01-01
Full Text Available Mycetoma is a chronic granulomatous disease that is more common in tropical than in temperate regions. Early diagnosis is important due to the therapeutic implications. Although biopsy and microbiological culture provide definitive diagnosis, they are time-consuming procedures and may not be able to provide a definite diagnosis in cases of fastidious organisms. The "dot-in-circle" sign has recently been proposed as a highly specific magnetic resonance imaging (MRI and ultrasonography (USG sign of mycetoma, which may allow a noninvasive as well as early diagnosis. We present a case of histologically proven mycetoma that demonstrated this sign.
Kaiser, W; Völker, A
1986-11-15
From the view of regional history for the Anhaltine territory several medical and natural scientists are to be mentioned whom a remarkable role can be ascribed in the Weimarian circle round Goethe. The Bernburg physician and pharmaceutist Bucholz became there for many years his consultee for questions of natural sciences; Gren, who also came from Bernburg, became the antipode in the dispute about problems of optics. Goethe visited Gilbert, who was educated in Dessau, in his laboratory in Halle. In old age the poet was supported as physician and friend by Carl Vogel, born in Dessau, who described Goethe's last disease.
Aircraft Detection from VHR Images Based on Circle-Frequency Filter and Multilevel Features
Gao, Feng; Li, Bo
2013-01-01
Aircraft automatic detection from very high-resolution (VHR) images plays an important role in a wide variety of applications. This paper proposes a novel detector for aircraft detection from very high-resolution (VHR) remote sensing images. To accurately distinguish aircrafts from background, a circle-frequency filter (CF-filter) is used to extract the candidate locations of aircrafts from a large size image. A multi-level feature model is then employed to represent both local appearance and spatial layout of aircrafts by means of Robust Hue Descriptor and Histogram of Oriented Gradients. The experimental results demonstrate the superior performance of the proposed method. PMID:24163637
ABSOLUTE STABILIZATION RELATED TO CIRCLE CRITERION: AN LMI-BASED APPROACH
Institute of Scientific and Technical Information of China (English)
杨莹; 黄琳
2003-01-01
A method is proposed for synthesizing output feedback controllers for nonlinear Lur' e systems. The problem of designing an output dynamic controller for uncertain-free systems and systems subject to multiplicative norm-bounded perturbations in the linear part were proposed respectively. The procedure is based on the use of the absolute stability,through the circle criterion, and a linear matrix inequalities (LMI) formulation. The controller existence conditions are given in terms of existence of suitable solutions to a set of parameter- dependent LMIs.
Directory of Open Access Journals (Sweden)
Ivan H. Lenchuk
2014-02-01
Full Text Available Presented article concerns construction problems in plane geometry. Solved the problem of the formation of students' stereotypes efficient, economical in time visual representation of algorithms for solving problems on the modern computer screens. Used universal author’s method of fragmented typing tasks on the method of circles. Allocated rod-type problem with its subsequent filling with ingredients. Previously developed educational software (partially, GeoGebra ensure optimal realization of the construction. Their dynamic characteristics and constructive capabilities - quality visual- shaped stages of "evidence" and "research".
Directory of Open Access Journals (Sweden)
Jenny Göransson
Full Text Available Detection and identification of pathogens in environmental samples for biosecurity applications are challenging due to the strict requirements on specificity, sensitivity and time. We have developed a concept for quick, specific and sensitive pathogen identification in environmental samples. Target identification is realized by padlock- and proximity probing, and reacted probes are amplified by RCA (rolling-circle amplification. The individual RCA products are labeled by fluorescence and enumerated by an instrument, developed for sensitive and rapid digital analysis. The concept is demonstrated by identification of simili biowarfare agents for bacteria (Escherichia coli and Pantoea agglomerans and spores (Bacillus atrophaeus released in field.
Probabilistic signatures of spatiotemporal intermittency in the coupled sine circle map lattice
Indian Academy of Sciences (India)
Zahera Jabeen; Neelima Gupta
2008-06-01
The phase diagram of the coupled sine circle map system exhibits a variety of interesting phenomena including spreading regions with spatiotemporal intermittency, non-spreading regions with spatial intermittency, and coherent structures termed solitons. A spreading to non-spreading transition is seen in the system. A cellular automaton version of the coupled system maps the spreading to non-spreading transition to a transition from a probabilistic to a deterministic cellular automaton. The solitonic sector of the system shows spatiotemporal intermittency with soliton creation, propagation and absorption. A probabilistic cellular automaton mapping is set up for this sector which can identify each one of these phenomena.
Lebetus scorpioides and Buenia jeffreysii (Teleostei: Gobiidae found north of the Arctic Circle
Directory of Open Access Journals (Sweden)
Ingvar Byrkjedal
2016-05-01
Full Text Available Two gobiid species, Lebetus scorpioides and Buenia jeffreysii, were recorded in northern Norway, for the first time north of the Arctic Circle. While both species were found on the continental shelf west of the Lofoten islands, one of them, L. scorpioides, was found north of 70°N off western Finnmark. The records represent a considerable northward extension of the distribution of these species. Being well within the size of reproductive individuals, the specimens appear to belong to resident populations most probably missed by earlier samplings.
Aircraft Detection from VHR Images Based on Circle-Frequency Filter and Multilevel Features
Directory of Open Access Journals (Sweden)
Feng Gao
2013-01-01
Full Text Available Aircraft automatic detection from very high-resolution (VHR images plays an important role in a wide variety of applications. This paper proposes a novel detector for aircraft detection from very high-resolution (VHR remote sensing images. To accurately distinguish aircrafts from background, a circle-frequency filter (CF-filter is used to extract the candidate locations of aircrafts from a large size image. A multi-level feature model is then employed to represent both local appearance and spatial layout of aircrafts by means of Robust Hue Descriptor and Histogram of Oriented Gradients. The experimental results demonstrate the superior performance of the proposed method.
The rapid plasma reagin (circle) card test in biological false positive and leprosy sera
Garner, M. F.; Backhouse, J. L.
1972-01-01
The rapid plasma reagin (RPR) circle card and the Venereal Disease Reference Laboratory (VDRL) slide test results were compared on a group of sera known to show biological false positive (BFP) reactions to reagin detection tests for syphilis. The RPR test was more specific than the VDRL test on the sera selected, ie, it gave fewer false positive results than the VDRL test. However, in a group of presumed normal sera, the RPR test gave BFP reactions while the VDRL test gave none. The RPR test gave fewer BFP reactions than the VDRL test in 269 sera from patients with lepromatous leprosy. PMID:5086221
A small 50 K cooling device for a quarter-circle Eulerian cradle diffractometer
Energy Technology Data Exchange (ETDEWEB)
Zobel, D.; Luger, P. (Freie Univ. Berlin (Germany, F.R.). Inst. fuer Kristallographie)
1990-06-01
A one-stage He refrigerator (Displex CS1003) has been modified and installed on a quarter-circle Eulerian cradle of 250 mm diameter (AED Siemens) and has been operated down to 50 K. The mechanical interface, which can easily be mounted, is described as well as some alignment problems. The device is suitable for any Eulerian cradle 250 mm or larger. Structure redeterminations of two organic compounds were carried out at 52 K. R values of 2.2 and 3.6% were obtained and proved the quality of this set up. (orig.).
PERANGKAT PEMBELAJARAN PERISTIWA ALAM DENGAN MODEL COOPERATIVE LEARNING TIPE INSIDE OUTSIDE CIRCLE
Directory of Open Access Journals (Sweden)
Diah Sunarsih
2015-08-01
Full Text Available Tujuan penelitian ini menghasilkan perangkat pembelajaran IPA dengan model pembelajaran cooperative learning tipe inside outside circle untuk dapat meningkatkan kemampuan berpikir kognitif dan menumbuhkan kemampuan komunikasi ilmiah siswa yang valid materi peristiwa alam. Uji coba skala terbatas dilakukan di SDN 02 Ambowetan. Uji coba skala luas kelas eksperimen SDN 01 Ambowetan VA, sedangkan kelas kontrol SDN 01 Ambowetan VB. Desain uji coba penelitian ini nonequivalent control group design. Prosedur pengembangan dan penelitian dikembangkan mengacu model pengembangan Dick dan Carry terdiri 4 tahap yaitu define, design, develop, dan disseminate. Hasil penelitian diperoleh pengembangan perangkat pembelajaran menerapkan model pembelajaran cooperative learning tipe inside outside circle berupa silabus, RPP, bahan ajar, lembar tes formatif, lembar observasi kemampuan komunikasi ilmiah, dan angket respon siswa valid, efektif, dan praktis diterapkan dalam pembelajaran IPA kelas V sekolah dasar materi peristiwa alam. Perangkat pembelajaran valid dengan nilai skor validitas akhir 3,43. Perangkat pembelajaran efektif terlihat peningkatan hasil uji N-gain menunjukkan hasil 0,50 pada klasifikasi tingkat sedang dan prosentase kemampuan ilmiah kelas eksperimen hasil sebesar 82%. Kriteria praktis dari nilai angket menunjukkan respon siswa kelas eksperimen lebih tinggi dibandingkan kelas kontrol (73% > 67 %.Purpose of this study is produce device the learning cooperative learning type inside outside circle to improve cognitive ability students and foster communication skills scientific a valid on material natural events. Trials limited scale in the SDN 02 Ambowetan. Trials wide scale for experimental class in the SDN 01 Ambowetan 5A, while the control class SDN 01 Ambowetan 5B. Design wide scale nonequivalent control group design. Procedures the development and developed research Dick and Carry consisting of 4 stage define, design, develop, and disseminate
The "Dot in Circle" Sign on MRI in Maduramycosis: A Characteristic Finding
Directory of Open Access Journals (Sweden)
Vikash Jain
2012-01-01
Full Text Available Mycetoma or Maduramycosis is a localized chronic suppurative infection characterized by exuberant granulation tissue, discharging sinuses, and bone involvement later in the course of the disease. Early clinical diagnosis before the appearance of sinuses and grains (aggregates of organism surrounded by granulation tissue, which are discharged from the draining sinuses is difficult. Delay in diagnosis may lead to amputation of the affected part. Definitive diagnosis is through biopsy and microbiological examination. However, at times diagnosis may still be difficult. The recently described "dot in circle" sign on magnetic resonance imaging (MRI is easy to recognize and highly specific. We present a case of mycetoma foot with characteristic MRI features.
Rigid motions: action-angles, relative cohomology and polynomials with roots on the unit circle
Francoise, Jean Pierre; Gallavotti, Giovanni
2012-01-01
Revisiting canonical integration of the classical solid near a uniform rotation, canonical action angle coordinates, hyperbolic and elliptic, are constructed in terms of various power series with coefficients which are polynomials in a variable $r^2$ depending on the inertia moments. Normal forms are derived via the analysis of a relative cohomology problem and shown to be obtainable without the use of ellitptic integrals (unlike the derivation of the action-angles). Results and conjectures also emerge about the properties of the above polynomials and the location of their roots. In particular a class of polynomials with all roots on the unit circle arises.
Institute of Scientific and Technical Information of China (English)
冉净斐
2012-01-01
商圈对于城市发展具有重要的功能和作用。文章分析了区域性中心城市必须拥有自己商圈的原因,回答了对商圈建设的种种疑问,研究了商圈建设必须统筹考虑商圈规模、建筑风格和业态布局等因素,提出了通过统一思想、科学规划、审慎拆迁、招商引资、资金投入等措施来建设商圈。%Business circle has important function and role on expanding city.This paper analyzes the Jiangjin must have their own core business circle,answering to the questions whether the business circle construction,Must consider as a whole circle scale,architectural style and industry structure and other factors.The paper puts forward through the unified thought,scientific planning,prudent demolition,capital attraction and capital investment to the construction of business circle.
Directory of Open Access Journals (Sweden)
Na LI
2014-11-01
Full Text Available Objective: To explore the application of quality control circle in raising compliance of the head of a bed in neurosurgery ICU nurses. Methods: The quality control circle was made up of 4 ICU nurses, determine the subject in order to improve the neurosurgery ICU nurses in raising compliance of the head of a bed, according to the QCC activity steps to formulate plans, including grasp the current situation, goal setting, through analysis, circle members develop strategy and plan implementation and review, finally compared the situation before and after neurosurgery ICU nurses raised bed activities compliance. Results: After implementation of QCC, neurosurgery ICU nurses raised bed to 30 ~ 45 degrees. After activities, circle members in the team cooperation ability, cohesion, to accept new things ability, and innovative thinking ability and to raise the understanding of the relevant knowledge of the head of a bed has improved significantly. Conclusion: The application of quality management circle activity improves the neurosurgery ICU nurses effectively raise the compliance of the head of a bed, improve the comprehensive quality of the clinical nurses.