scholarly journals Same Principles but Different Purposes: Passive Fluid Handling throughout the Animal Kingdom

2019 ◽  
Vol 59 (6) ◽  
pp. 1673-1680 ◽  
Author(s):  
Anna-Christin Joel ◽  
Margret Weissbach
Keyword(s):  
Selection Pressure ◽  
Arid Regions ◽  
Capillary Forces ◽  
Animal Kingdom ◽  
Defense Secretion ◽  
Fluid Handling ◽  
Similarities And Differences ◽  
Physical Laws ◽  
Physical Phenomena

Abstract Everything on earth is subject to physical laws, thus they influence all facets of living creatures. Although these laws restrain animals in many ways, some animals have developed a way to use physical phenomena in their favor to conserve energy. Many animals, which have to handle fluids, for example, have evolved passive mechanisms by adapting their wettability or using capillary forces for rapid fluid spreading. In distinct animals, a similar selection pressure always favors a convergent development. However, when assessing the biological tasks of passive fluid handling mechanisms, their diversity is rather surprising. Besides the well-described handling of water to facilitate drinking in arid regions, observed in, e.g., several lizards, other animals like a special flat bug have developed a similar mechanism for a completely different task and fluid: Instead of water, these bugs passively transport an oily defense secretion to a region close to their head where it finally evaporates. And again some spiders use capillary forces to capture prey, by sucking in the viscous waxy cuticle of their prey with their nanofibrous threads. This review highlights the similarities and differences in the deployed mechanisms of passive fluid handling across the animal kingdom. Besides including well-studied animals to point out different mechanisms in general, we stretch over to not as extensively studied species for which similar mechanisms are described for different tasks. Thus, we provide an extensive overview of animals for which passive fluid handling is described so far as well as for future inspiration.

The REPAS Study: Reliability Evaluation of Passive Safety Systems

2002 ◽  
Author(s):  
M. E. Ricotti ◽  
F. Bianchi ◽  
L. Burgazzi ◽  
F. D’Auria ◽  
G. Galassi
Keyword(s):  
Initial Conditions ◽  
Natural Circulation ◽  
Quantitative Information ◽  
External Input ◽  
Passive System ◽  
Two Phase ◽  
Passive Safety Systems ◽  
Safety Systems ◽  
Physical Laws ◽  
Physical Phenomena

The strategy of approach to the problem moves from the consideration that a passive system should be theoretically more reliable than an active one. In fact it does not need any external input or energy to operate and it relies only upon natural physical laws (e.g. gravity, natural circulation, internally stored energy, etc.) and/or “intelligent” use of the energy inherently available in the system (e.g. chemical reaction, decay heat, etc.). Nevertheless the passive system may fail its mission not only as a consequence of classical mechanical failure of components, but also for deviation from the expected behaviour, due to physical phenomena mainly related to thermalhydraulics or due to different boundary and initial conditions. The main sources of physical failure are identified and a probability of occurrence is assigned. The reliability analysis is performed on a passive system which operates in two-phase, natural circulation. The selected system is a loop including a heat source and a heat sink where the condensation occurs. The system behavior under different configurations has been simulated via best-estimate code (Relap5 mod3.2). The results are shown and can be treated in such a way to give qualitative and quantitative information on the system reliability. Main routes of development of the methodology are also depicted.

scholarly journals USE OF MOBILE DEVICE SENSORS TO CONDUCT THE PHYSICAL EXPERIMENT

2019 ◽  
pp. 345-354
Author(s):  
Sergii Tereschuk ◽  
Vira Kolmakova
Keyword(s):  
Stem Education ◽  
Mobile Device ◽  
Mobile Application ◽  
Positive Impact ◽  
Physical Experiment ◽  
Science Journal ◽  
Conservation Of Energy ◽  
Physical Experiments ◽  
Physical Laws ◽  
Physical Phenomena

The concept of "sensor" in the system of physical experiment at school is considered in the article. The possibility of using sensors in physics lessons is substantiated: transformation of an input signal into an output is accompanied by transformation of one type of energy into another (according to the law of conservation of energy), and the functioning of the sensors are based on physical phenomena (physical effects or principles), which are described by the relevant physical laws. The article deals with the methodical aspects of using the Google Science Journal mobile application in physics lessons. This application allows you to use the sensors of your mobile device for a physical experiment. As an example we consider the frontal laboratory work "Determination of the period of oscillation of the mathematical pendulum". The method of its carrying out is offered in two approaches: the first one involves the traditional technique of conducting the experiment, and the second approach is using the mobile application Google Science Journal. The article shows that the use of smartphone sensors in physics lessons has perspectives in the context of STEM education. Thus, the use of the considered application is of current importance and requires further scientific and methodological research on its use in the high school physical experimentation system. The Science Journal mobile application can be used to connect external sensors, which will have a positive impact on the introduction of STEM education, and to use Arduino in the demonstration of physical experiments by a physics teacher. Connecting sensors using an Arduino microcontroller is particularly promising in creative lab work on physics.

scholarly journals A new hybridization filtering-based linear-nonlinear models for time series forecasting

2021 ◽  
Author(s):  
Mehrnaz Ahmadi ◽  
◽  
Mehdi Khashei ◽  
Keyword(s):  
Hybrid Methods ◽  
Nonlinear Models ◽  
Prediction Methods ◽  
Short Term ◽  
Forecasting Methods ◽  
Primary Relationships ◽  
Time Dependencies ◽  
Physical Laws ◽  
Face Time ◽  
Physical Phenomena

In recent years, the idea of using a mathematical model to describe the behavior of physical phenomena has been very much considered. Specifically, a definitive model, based on physical laws, enables researchers to calculate the number of time dependencies precisely at any moment in time. However, in the real world, we often face time-dependent phenomena with many unknown or unavailable factors (Lindley, 2010; Roulston et al., 2003). In this case, when it is not possible to achieve a definite - model, the prediction methods are wide used, especially when the past observations of a variable and primary relationships between specific observations are available. Forecasting methods that are used in different fields of science can be categorized based on various aspects. For example, the prediction methods used in the field of wind energy can be divided into four categories of 1) ultra short term (several seconds to four hours), 2) short term (4 to 24 hours), 3) medium-term (1 to 7 days), and 4) long term (more than 7 days) (Zack, 2003; Soman et al., 2010). Also, the structure of forecasting methods can be divided into two types of 1) single methods and 2) hybrid methods. Each of these categories can also be subdivided into smaller subgroups.

scholarly journals J. David Jackson (January 19, 1925–May 20, 2016): A Biographical Memoir

2021 ◽  
Vol 71 (1) ◽  
pp. 23-36
Author(s):  
Robert N. Cahn
Keyword(s):  
Civil Liberties ◽  
The United States ◽  
Classical Electrodynamics ◽  
Muon Catalyzed Fusion ◽  
Particle Collisions ◽  
Superconducting Super Collider ◽  
Theoretical Physicist ◽  
Andrei Sakharov ◽  
Physical Laws ◽  
Physical Phenomena

John David (“Dave”) Jackson, a Canadian-born theoretical physicist, contributed significantly to particle, nuclear, and atomic physics. He is best known, however, for his text Classical Electrodynamics, which has been a fixture in physics graduate education around the world for more than 50 years. It is generally referred to simply as “Jackson.” This textbook, which has inspired fear and wonder alike in generations of students, clearly reflects the author's fascination with physical phenomena, his renowned mathematical dexterity, and his appreciation of the elegance of physical laws. Jackson's major contributions to research included the theory of muon-catalyzed fusion; the analysis, with Kurt Gottfried, of angular distributions in quasi-two-body elementary particle collisions; and the elucidation of charmonium-state decays. Jackson influenced the development of physics research throughout the United States as well as internationally—particularly through his work on the nascent Superconducting Super Collider. An active promoter of civil liberties and human rights, he was one of the leaders of the efforts to free Andrei Sakharov, Yuri Orlov, and Anatoly Shcharansky from Soviet imprisonment.

scholarly journals Handbook of bi-dimensional tensors: Part I: Harmonic decomposition and symmetry classes

2016 ◽  
Vol 22 (9) ◽  
pp. 1847-1865 ◽  
Author(s):  
N Auffray ◽  
B Kolev ◽  
M Olive
Keyword(s):  
General Problem ◽  
Strain Gradient ◽  
Gradient Elasticity ◽  
Strain Gradient Elasticity ◽  
Symmetry Classes ◽  
Different Types ◽  
Tensor Spaces ◽  
Harmonic Decomposition ◽  
Physical Laws ◽  
Physical Phenomena

To investigate complex physical phenomena, bi-dimensional models are often an interesting option. It allows spatial couplings to be produced while keeping them as simple as possible. For linear physical laws, constitutive equations involve the use of tensor spaces. As a consequence the different types of anisotropy that can be described are encoded in tensor spaces involved in the model. In the present paper, we solve the general problem of computing symmetry classes of constitutive tensors in [Formula: see text] using mathematical tools coming from representation theory. The power of this method is illustrated through the tensor spaces of Mindlin strain-gradient elasticity.

scholarly journals PHYSICAL THEORIES IN THE SCHOOL COURSE

2020 ◽  
Vol 71 (3) ◽  
pp. 133-138
Author(s):  
D.M. Nurbaeva ◽  
◽  
B. Yerzhenbek ◽  
Zh.M. Nurmukhamedova ◽  
D.M Nasirova ◽  
...  
Keyword(s):  
Physical Theory ◽  
Ideal Model ◽  
Specific Knowledge ◽  
Study Material ◽  
The World ◽  
Basic School ◽  
Physical Laws ◽  
Physics Course ◽  
Physical Phenomena ◽  
Main Material

The content of the school physics course is the basics of science-physics, which is a system of knowledge about the world around us. An ideal model of nature that includes General concepts, principles, and hypotheses of physics and characterizes a certain stage of its development is called a physical picture of the world. The meaning of physical theory in science, concepts, laws, and theories are the source of specific knowledge in explaining and describing a particular phenomenon. The basic school physics course is a course that studies physical phenomena (mechanical, thermal, electrical, electromagnetic, light) and physical laws; the study material is grouped around physical phenomena, which are arranged in the course in order of complexity of the forms of motion of matter. The basic school physics course should be as complete as possible and cover the main material of all sections of the physics course.

scholarly journals From the dicey world to the physical laws: dice toy models for bridging microscopic and macroscopic understanding of physical phenomena

2019 ◽  
Vol 1287 ◽  
pp. 012026
Author(s):  
Pasquale Onorato ◽  
Luigi M Gratton ◽  
Stefano Oss ◽  
Massimiliano Malgieri
Keyword(s):  
Physical Laws ◽  
Physical Phenomena

scholarly journals On Frequency Combs in Monolithic Resonators

Nanophotonics ◽  
2016 ◽  
Vol 5 (2) ◽  
pp. 363-391 ◽  
Author(s):  
A. A. Savchenkov ◽  
A. B. Matsko ◽  
L. Maleki
Keyword(s):  
Frequency Comb ◽  
Microring Resonator ◽  
Optical Metrology ◽  
Optical Frequency ◽  
Optical Frequency Combs ◽  
Frequency Combs ◽  
Pulse Generators ◽  
Similarities And Differences ◽  
Microwave Sources ◽  
Physical Phenomena

AbstractOptical frequency combs have become indispensable in astronomical measurements, biological fingerprinting, optical metrology, and radio frequency photonic signal generation. Recently demonstrated microring resonator-based Kerr frequency combs point the way towards chip scale optical frequency comb generator retaining major properties of the lab scale devices. This technique is promising for integrated miniature radiofrequency and microwave sources, atomic clocks, optical references and femtosecond pulse generators. Here we present Kerr frequency comb development in a historical perspective emphasizing its similarities and differences with other physical phenomena. We elucidate fundamental principles and describe practical implementations of Kerr comb oscillators, highlighting associated solved and unsolved problems.

scholarly journals How Weird is The Worm? Evolution of the Developmental Gene Toolkit in Caenorhabditis elegans

2019 ◽  
Vol 7 (4) ◽  
pp. 19 ◽  
Author(s):  
Emily A. Baker ◽  
Alison Woollard
Keyword(s):  
Developmental Biology ◽  
Natural Selection ◽  
Comparative Genomics ◽  
Evolutionary Developmental Biology ◽  
Genomic Variation ◽  
Developmental Gene ◽  
Animal Kingdom ◽  
Animal Development ◽  
Similarities And Differences ◽  
Fruitful Research

Comparative developmental biology and comparative genomics are the cornerstones of evolutionary developmental biology. Decades of fruitful research using nematodes have produced detailed accounts of the developmental and genomic variation in the nematode phylum. Evolutionary developmental biologists are now utilising these data as a tool with which to interrogate the evolutionary basis for the similarities and differences observed in Nematoda. Nematodes have often seemed atypical compared to the rest of the animal kingdom—from their totally lineage-dependent mode of embryogenesis to their abandonment of key toolkit genes usually deployed by bilaterians for proper development—worms are notorious rule breakers of the bilaterian handbook. However, exploring the nature of these deviations is providing answers to some of the biggest questions about the evolution of animal development. For example, why is the evolvability of each embryonic stage not the same? Why can evolution sometimes tolerate the loss of genes involved in key developmental events? Lastly, why does natural selection act to radically diverge toolkit genes in number and sequence in certain taxa? In answering these questions, insight is not only being provided about the evolution of nematodes, but of all metazoans.

scholarly journals THE PHYSICS OF LEONARDO DA VINCI

2020 ◽  
Author(s):  
Ferdinando Borsa
Keyword(s):  
Da Vinci ◽  
Present Note ◽  
Leonardo Da Vinci ◽  
Scientific Methodology ◽  
Experimental Science ◽  
The Many ◽  
Physical Laws ◽  
Physical Phenomena

Among the many extraordinary activities of Leonardo da Vinci there are a few examples when he confronts himself with physical phenomena that he tries to explain. However, the studies of physical laws by Leonardo does not seem to be motivated by the interest in Physics itself but rather by the explanation of phenomena entering in his activity of artist, engineer and observer of nature. Nevertheless it is surprising that the renaissance genius is able to enunciate the paradigm of modern experimental science as later established by Galileo and Newton. In the present note, after having reviewed some of the most spectacular intuitions by Leonardo in the field of physics, we try to verify to which extent he applies the scientific methodology, he so well enunciates, to the study of physical laws. Among the very extensive production of Leonardo we chose to analyze in detail the studies on friction and on hydrodynamics since these are the subjects that he pursued with more continuity and method.

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