scholarly journals Extrasolar planet interactions

2007 ◽  
Vol 3 (S249) ◽  
pp. 469-478
Author(s):  
Rory Barnes ◽  
Richard Greenberg
Keyword(s):  
Planetary Systems ◽  
Equal Mass ◽  
Dynamical Instability ◽  
Hill Stability ◽  
Resonant Interactions ◽  
Stability And Instability ◽  
Different Types ◽  
Set Up ◽  
Type Of Stability ◽  
Two Parameters

AbstractThe dynamical interactions of planetary systems may be a clue to their formation histories. Therefore, the distribution of these interactions provides important constraints on models of planet formation. We focus on each system's apsidal motion and proximity to dynamical instability. Although only ∼25 multiple planet systems have been discovered to date, our analyses in these terms have revealed several important features of planetary interactions. 1) Many systems interact such that they are near the boundary between stability and instability. 2) Planets tend to form such that at least one planet's eccentricity periodically drops to near zero. 3) Mean-motion resonant pairs would be unstable if not for the resonance. 4) Scattering of approximately equal mass planets is unlikely to produce the observed distribution of apsidal behavior. 5) Resonant interactions may be identified through calculating a system's proximity to instability, regardless of knowledge of angles such as mean longitude and longitude of periastron (e.g. GJ 317 b and c are probably in a 4:1 resonance). These properties of planetary systems have been identified through calculation of two parameters that describe the interaction. The apsidal interaction can be quantified by determining how close a planet is to an apsidal separatrix (a boundary between qualitatively different types of apsidal oscillations, e.g. libration or circulation of the major axes). This value can be calculated through short numerical integrations. The proximity to instability can be measured by comparing the observed orbital elements to an analytic boundary that describes a type of stability known as Hill stability. We have set up a website dedicated to presenting the most up-to-date information on dynamical interactions: http://www.lpl.arizona.edu/~rory/research/xsp/dynamics.

Exploration of the Early Childhood Care and Education Provided in Kindergartens in Japan

2019 ◽  
Vol 8 (2) ◽  
pp. 24-29
Author(s):  
Manjinder Kaur
Keyword(s):  
Early Childhood ◽  
World War Ii ◽  
World War ◽  
High Quality ◽  
Early Childhood Care ◽  
Childhood Care ◽  
Different Types ◽  
Education And Care ◽  
Set Up ◽  
Shed Light

This study tends to shed light on early childhood care and education (ECCE) institutions with special reference to kindergartens in Fukuoka, Japan. The choice of the topic for study was derived by the importance of ECCE in children’s life and huge economic growth of Japan after worst effects of world war-II, which are thought to be linked with the education that children receives in Japan. The study is limited to four kindergartens in Fukuoka City and observations made for the study refers to 2018. Herein, different types of institutions providing ECCE, their infrastructural set-up, activities, along with curriculum are discussed. At the end, issues and challenges of ECCE system in Japan are discussed. It has been observed that the infrastructural facility and nature of activities are of high quality. Each and every care is being taken to inculcate habits, as well as to maintain physical and intellectual growth of children. The children seem to be highly happy and enjoy learning via various activities in these schools. It is clear that the devised policies on education and care of children are implemented in full spirit.

scholarly journals Analysis of Errors in the Estimation of Impact Positions in Plate-Like Structure through the Triangulation Formula by Piezoelectric Sensors Monitoring

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3426 ◽  
Author(s):  
Eugenio Marino-Merlo ◽  
Andrea Bulletti ◽  
Pietro Giannelli ◽  
Marco Calzolai ◽  
Lorenzo Capineri
Keyword(s):  
Propagation Velocity ◽  
Lamb Waves ◽  
Correlation Method ◽  
Time Of Arrival ◽  
Impact Point ◽  
Laboratory Procedure ◽  
Impact Position ◽  
Set Up ◽  
Two Parameters ◽  
The Impact

The structural health monitoring (SHM) of critical structures is a complex task that involves the use of different sensors that are also aimed at the identification of the location of the impact point using ultrasonic sensors. For the evaluation of the impact position, reference is often made to the well-known triangulation method. This method requires the estimation of the differential time of arrival (DToA) and the group velocity of the Lamb waves propagating into a plate-like structure: the uncertainty of these two parameters is taken into consideration as main cause of localization error. The work proposes a simple laboratory procedure based on a set-up with a pair of sensors that are symmetrically placed with respect to the impact point, to estimate the uncertainty of the DToA and the propagation velocity estimates. According to a theoretical analysis of the error for the impact position, the experimental uncertainties of DToA and the propagation velocity are used to estimate the overall limit of the SHM system for the impact positioning. Because the error for the DToA estimate depends also on the adopted signal processing, three common methods are selected and compared: the threshold, the correlation method, and a likelihood algorithm. Finally, the analysis of the positioning error using multisensory configuration is reported as useful for the design of the SHM system.

scholarly journals Evidence That Supertriangles Exist in Nature from the Vertical Projections of Koelreuteria paniculata Fruit

Symmetry ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 23
Author(s):  
Yuping Li ◽  
Brady K. Quinn ◽  
Johan Gielis ◽  
Yirong Li ◽  
Peijian Shi
Keyword(s):  
Root Mean Square ◽  
Goodness Of Fit ◽  
Mean Square ◽  
Sea Stars ◽  
Different Types ◽  
Koelreuteria Paniculata ◽  
Two Parameters ◽  
Mean Square Errors

Many natural radial symmetrical shapes (e.g., sea stars) follow the Gielis equation (GE) or its twin equation (TGE). A supertriangle (three triangles arranged around a central polygon) represents such a shape, but no study has tested whether natural shapes can be represented as/are supertriangles or whether the GE or TGE can describe their shape. We collected 100 pieces of Koelreuteria paniculata fruit, which have a supertriangular shape, extracted the boundary coordinates for their vertical projections, and then fitted them with the GE and TGE. The adjusted root mean square errors (RMSEadj) of the two equations were always less than 0.08, and >70% were less than 0.05. For 57/100 fruit projections, the GE had a lower RMSEadj than the TGE, although overall differences in the goodness of fit were non-significant. However, the TGE produces more symmetrical shapes than the GE as the two parameters controlling the extent of symmetry in it are approximately equal. This work demonstrates that natural supertriangles exist, validates the use of the GE and TGE to model their shapes, and suggests that different complex radially symmetrical shapes can be generated by the same equation, implying that different types of biological symmetry may result from the same biophysical mechanisms.

scholarly journals EFFECTS OF DIFFERENT TYPES OF CYTOPLASM ON THE KERNEL ROW NUMBER OF MAIZE INBRED LINES

AGROFOR ◽  
2018 ◽  
Vol 2 (2) ◽  
Author(s):  
Snežana JOVANOVIĆ ◽  
Goran TODOROVIĆ ◽  
Nikola GRČIĆ ◽  
Ratibor ŠTRBANOVIĆ ◽  
Rade STANISAVLJEVIĆ ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Block Design ◽  
Inbred Lines ◽  
Mean Values ◽  
Maize Inbred Lines ◽  
Different Types ◽  
Maize Inbreds ◽  
Set Up ◽  
Kernel Row Number

The aim of the present study was to determine effects of both, different types ofcytoplasm (cms-C, cms-S and fertile) and environmental factors on the kernel rownumber of 12 maize inbreds lines. The trial with inbred lines was set up in twolocations (Zemun Polje-Selection field and Zemun Polje-Školsko dobro) in 2013and 2014. Moreover, the three-replicate trials were set up according to therandomised complete block design within each type of cytoplasm. Each plot withinthe replicate consisted of four rows. Fertile versions of inbred lines were sown intwo border rows and they were pollinators for their sterile counterparts. Statisticbiometricdata processing was based on mean values per replicate and included theanalysis of variance. According to this analysis, significant differences in thekernel row number were established among inbred lines in dependence on the typeof cytoplasm, year and the location. The average kernel row number ranged from10.3 (L9) to 15.8 (L5 and L7). The variation of the kernel row number, related to thesource of cytoplasm, was very significant. Differences (Lsd0.01) in the kernel rownumber were not determined in inbred lines L5, L8, L10 and L12 in regard to the typeof cytoplasm: cms-C, cms-S and fertile. The average kernel row numbersignificantly (P1%) varied in regard to the year of investigation. A higher averagevalue (13.75) was established in 2014 than in 2013 (13.31). The kernel row numberper year very significantly varied (Lsd0.01) in all inbreds, but the differences werenot significant in the inbreds L2, L3, L8, L9 and L12. Gained results point out toeffects of different types of cytoplasm on the kernel row number.

scholarly journals Controlling and the Use of UAVs as Important Components of Smart Logistical Operations

2021 ◽  
Vol 12 (1) ◽  
pp. 192-203
Author(s):  
Martin Holubčík ◽  
Jakub Soviar
Keyword(s):  
Decision Making ◽  
Internal State ◽  
Good Decision ◽  
Interdisciplinary Field ◽  
Different Types ◽  
Way Of Thinking ◽  
Set Up ◽  
Controlling Measures ◽  
A Company ◽  
The Way

Abstract Modern controlling is an interdisciplinary field that allows management to manage properly, thereby creating the basis for good decision-making. Logistics operations in smart companies need to be not only properly set up, but also properly controlled and improved. The purpose of the article is to analyze the controlling environment in a selected company and point out possible improvements in logistics activities and devices, with a view to preventing different types of problems. For this purpose, observations of the internal logistics processes in a selected company were used and quantified to assess its internal state. On the basis of the data, controlling measures are put forward to improve the management of the company’s logistics activities. The results of the research highlight the opportunities that exist through controlling activities to collect and analyze information about the logistics activities of a company. By doing so, employees can be given greater responsibility for the fulfilment of their tasks and contribute to the streamlining of logistics processes. For managers, the implementation of controlling represents a change in the way of thinking and managing a company.

Establishing the Credibility of Social Web Applications

2011 ◽  
pp. 1432-1437
Author(s):  
Pankaj Kamthan
Keyword(s):  
Web 2.0 ◽  
Web Applications ◽  
Future Research ◽  
Social Web ◽  
The People ◽  
Different Types ◽  
Set Up ◽  
The Web

In recent years, there has been a steady shift in the nature of Web applications. The vehicle of this transition of Web applications is us, the people. The ability to post photographs or videos, exchange music snippets with peers, and annotate a piece of information, are but a few exemplars of this phenomenon. Indeed, the pseudonym Web 2.0 (O’Reilly, 2005) has been used to describe the apparent “socialization” of the Web. In spite of the significant prospects offered by humancentric Web applications, the mere fact that virtually anyone can set up such applications claiming to sell products and services or upload/post unscrutinized information on a topic as being “definitive,” raises the issues of credibility from a consumers’ viewpoint. Therefore, establishing credibility is essential for an organization’s reputation and for building consumers’ trust. The rest of the article is organized as follows. We first provide the background necessary for later discussion. This is followed by the introduction of a framework within which different types of credibility in the context of human-centric Web applications can be systematically addressed and thereby improved. Next, challenges and directions for future research are outlined. Finally, concluding remarks are given.

15. Business Organizations

2019 ◽  
pp. 421-451
Author(s):  
Lucy Jones
Keyword(s):  
Limited Liability ◽  
Business Organizations ◽  
Limited Partnership ◽  
Legal Personality ◽  
Different Types ◽  
The Common ◽  
The Difference ◽  
Set Up ◽  
Limited Liability Partnership ◽  
The Relationship

This chapter discusses the common types of business organizations and explains the difference between unincorporated and incorporated businesses. The three types of partnership arrangements are considered, namely a general (ordinary) partnership, a limited partnership, and a limited liability partnership. The chapter includes discussion of the rules relating to partnerships under the Partnership Act 1890 and the Limited Liability Partnership Act 2000. It explains how different types of partnerships may be set up and looks at the relationship between partners and the relationship between partnerships and outsiders. It considers the dissolution of the different types of partnerships. The chapter concludes with a discussion of the different types of companies and the separate legal personality of companies.

15. Business Organisations

2017 ◽  
Author(s):  
Lucy Jones
Keyword(s):  
Limited Liability ◽  
Limited Partnership ◽  
Legal Personality ◽  
Different Types ◽  
The Common ◽  
The Difference ◽  
Set Up ◽  
Limited Liability Partnership ◽  
The Relationship

This chapter discusses the common types of business organisations and explains the difference between unincorporated and incorporated businesses. The three types of partnership arrangements are considered, namely a general (ordinary) partnership, a limited partnership, and a limited liability partnership. The chapter includes discussion of the rules relating to partnerships under the Partnership Act 1890 and the Limited Liability Partnership Act 2000. It explains how different types of partnerships may be set up and looks at the relationship between partners and the relationship between partnerships and outsiders. It considers the dissolution of the different types of partnerships. The chapter concludes with a discussion of the different types of companies and the separate legal personality of companies.

scholarly journals Competitive interactions between species of freshwater snails: I. Laboratory: Ia. General methodology

1983 ◽  
Vol 78 (3) ◽  
pp. 335-341 ◽  
Author(s):  
Frederico Simões Barbosa ◽  
Dirceu P. Pereira da Costa ◽  
Francisco Arruda
Keyword(s):  
Laboratory Experiments ◽  
Freshwater Snail ◽  
Current Paper ◽  
Competitive Interactions ◽  
Laboratory Work ◽  
Freshwater Snails ◽  
Technical Advance ◽  
General Methodology ◽  
Different Types ◽  
Set Up

For the development of laboratory experiments on the competitive interacitons between freshwater snail populations, special snail rooms were set up in the main building of the Research Center "Aggeu Magalhães". In the current paper, the first of a series on this subject, the general methodology of the laboratory work is described in detail. Using indoor cement channels in which a uniform seminatural environment was created, interactions of freshwater snail populations can be studied with minimal interference of the usual variables. Controlled indoor environmental techniques, as described in the current paper, may also be utilized in different types of experiments in malacology, and represent a substantial technical advance in malacological work.

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