Relevant bibliographies by topics / Micro forces

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Micro forces'

Author: Grafiati
Published: 25 May 2024

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Micro forces.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Micro forces"

1

Su, Quanliang, and Michael D. Gilchrist. "Demolding forces for micron-sized features during micro-injection molding." Polymer Engineering & Science 56, no. 7 (April 4, 2016): 810–16. http://dx.doi.org/10.1002/pen.24309.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Perveen, Asma, M. Rahman, and Y. S. Wong. "Modeling of Vertical Micro Grinding." Key Engineering Materials 625 (August 2014): 463–68. http://dx.doi.org/10.4028/www.scientific.net/kem.625.463.

Full text
Abstract:
Due to the small feed rate used in micro-machining, ploughing force needs to be considered in addition to the chip formation force. A new analytical model has been proposed to calculate cutting forces of micro-grinding process based on the process configuration, work piece material properties, and micro-grinding tool topography. The proposed approach allows the calculation of cutting force comprising both the chip formation force and ploughing forcec considering single grain interaction.
APA, Harvard, Vancouver, ISO, and other styles
3

Yilmaz, Cagri, Ramazan Sahin, and Eyup Sabri Topal. "Theoretical study on the sensitivity of dynamic acoustic force measurement through monomodal and bimodal excitations of rectangular micro-cantilever." Engineering Research Express 3, no. 4 (November 25, 2021): 045035. http://dx.doi.org/10.1088/2631-8695/ac3a55.

Full text
Abstract:
Abstract We present a detailed analysis on measurement sensitivity of dynamic acoustic forces via numerical simulation of the micro-cantilever responses. The rectangular micro-cantilever is regarded as a point mass in the dynamic model of forced and damped harmonic oscillator. We use single- and bimodal-frequency excitation schemes for actuation of the micro-cantilever in the presence of dynamic acoustic forces. In bimodal-frequency excitation scheme, the micro-cantilever is excited at its first two eigenmode frequencies simultaneously as opposed to single-frequency excitation. First, we numerically obtain micro-cantilever deflections by solving the equations of Motions (EOMs) constructed for the first two eigenmodes. Then, we determine oscillation amplitude and phase shift as a function of acoustic force strength within different frequency regions. Moreover, we relate amplitude and phase shift to virial and energy dissipation in order to explore the interaction between flexural modes in multifrequency excitation. The simulation results point out that bimodal-frequency excitation improves the measurement sensitivity of dynamic acoustic forces at particular frequencies. Herein, simultaneous application of driving forces enables higher sensitivities of observables and energy quantities as acoustic force frequencies become around the eigenmode frequencies. For our case, we obtain the highest phase shift (∼178°) for the acoustic force strength of 100 pN at the frequency of around 307.2 kHz. Therefore, this method can be easily adapted to improve measurement sensitivity of dynamic acoustic forces in a wider frequency window.
APA, Harvard, Vancouver, ISO, and other styles
4

Wang, Z. W., G. Q. Pan, and Dong Hui Wen. "Applications of Ultrasonic Radiation Forces." Advanced Materials Research 215 (March 2011): 259–62. http://dx.doi.org/10.4028/www.scientific.net/amr.215.259.

Full text
Abstract:
This keynote paper aims at introducing applications of ultrasonic radiation force in industry. The chosen focus is to understand how to use it. Since the phenomenon of acoustic levitation can reflect the exciting of ultrasonic radiation force directly. The paper starts with an analysis on the tungsten ball floating on a sound field and ultrasonic micro-manipulation study in micro Electronic Mechanical System (MEMS). And ultrasound has been successfully used to degrade wastewater as its cavitation. At the same time, different kinds of micro-ultrasonic machining were used to show how exciting machining and ultrasonic radiation combined. A view from the authors and the final Conclusions show future applications of ultrasonic radiation force.
APA, Harvard, Vancouver, ISO, and other styles
5

Afazov, Shukri, Svetan Ratchev, and Joel Segal. "Effects of the Cutting Tool Edge Radius on the Stability Lobes in Micro-Milling." Advanced Materials Research 223 (April 2011): 859–68. http://dx.doi.org/10.4028/www.scientific.net/amr.223.859.

Full text
Abstract:
This paper investigates the effects of the cutting tool edge radius on the cutting forces and stability lobes in micro-milling. The investigation is conducted based on recently developed models for prediction of micro-milling cutting forces and stability lobes. The developed models consider the nonlinearities of the micro-milling process, such as nonlinear cutting forces due to cutting velocity dependencies, edge radius effect and run-out presence. A number of finite element analyses (FEA) are performed to obtain the cutting forces in orthogonal cutting which are used for determining the micro-milling cutting forces. The chip morphology obtained for different tool edge radii using FEA is presented. It is observed that at large tool edge radii the influence of the ploughing effect become more significant factor on the chip morphology. The results related to micro-milling cutting forces and stability lobes show that by enlarging the tool edge radius the micro-milling cutting forces increase while the stability limits decrease.
APA, Harvard, Vancouver, ISO, and other styles
6

Bhople, Narendra, Sachin Mastud, and Satish Satpal. "Modelling and analysis of cutting forces while micro end milling of Ti-alloy using finite element method." International Journal for Simulation and Multidisciplinary Design Optimization 12 (2021): 26. http://dx.doi.org/10.1051/smdo/2021027.

Full text
Abstract:
Micromilling is one of the preferable micro-manufacturing process, as it exhibits the flexibility to produce complex 3D micro-parts. The cutting forces generated in micro end milling can be attributed for tool vibration and process instability. If cutting forces are not controlled below critical limits, it may lead to catastrophic failure of tool. Cutting force has a significant role to decide the surface roughness. Therefore accurate prediction of cutting forces and selection of suitable cutting parameters mainly feed, is important while micro end milling. In present study, finite element method (FEM) based model has been developed by using ABAQUAS/Explicit 6.12 software. Von-Misses stresses and cutting forces are predicted while micro end milling of Ti-6Al-4V. Further, cutting forces were measured during experimentation using dynamometer mounted on micro-milling test bed. Cutting forces predicted by FEM model are in good agreement with the experimental force values. Obtained FEM results have been used to study the size effect in micro end milling process. Moreover, the effect of uncut chip thickness to cutting edge radius ratio (h/rc) on surface roughness (Ra) has been studied. It is found the feed 2.5 µm/tooth is suitable value to produce optimum surface roughness and cutting forces.
APA, Harvard, Vancouver, ISO, and other styles
7

Mekid, Samir. "Design and Testing of a Micro-Dynamometer for Desktop Micro-Milling Machine." Advanced Materials Research 902 (February 2014): 267–73. http://dx.doi.org/10.4028/www.scientific.net/amr.902.267.

Full text
Abstract:
The emerging miniaturized high-tech products are required to have increased functionalities of systems within a volumetric size on the order of 1 cm3. Hence, the parts are mesoscopic with complex microscopic features of a few mm length with machining accuracy of better than 1 micrometer with secured surface integrity as components will require high surface finish, tensile stress and crack free surfaces in order to function reliably. One of the characteristics to be measured is the cutting forces on the parts being machined. This paper will present the design, manufacture and testing of a miniature dynamometer capable of measuring cutting forces within a low range of 50N but with a resolution better than 1 mN and high frequency since the micromachining involves small cutting forces but the spindle rotates at high speed. The dynamometer is capable of measuring forces in five directions (±x, ±y, and z). The instrument was calibrated and exhibit very good results leading to a true validation. This instrument is assembled on a micro milling desktop machine designed in-house. It will not only support predicting the surface finish and chip thickness but also monitoring tool wear evolution and hence prevents/reduce tool breakage known to be one of the main issues in micro-milling.
APA, Harvard, Vancouver, ISO, and other styles
8

Mekhiel, S., A. Youssef, and Y. Elshaer. "ANALYSIS OF CUTTING FORCES IN MICRO MILLING." International Conference on Applied Mechanics and Mechanical Engineering 18, no. 18 (April 1, 2018): 1–18. http://dx.doi.org/10.21608/amme.2018.35004.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Anand, Ravi Shankar, Karali Patra, Markus Steiner, and Dirk Biermann. "Mechanistic modeling of micro-drilling cutting forces." International Journal of Advanced Manufacturing Technology 88, no. 1-4 (April 23, 2016): 241–54. http://dx.doi.org/10.1007/s00170-016-8632-2.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Malekian, Mohammad, Simon S. Park, and Martin B. G. Jun. "Modeling of dynamic micro-milling cutting forces." International Journal of Machine Tools and Manufacture 49, no. 7-8 (June 2009): 586–98. http://dx.doi.org/10.1016/j.ijmachtools.2009.02.006.

Full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Micro forces"

1

Johansson, LarsErik. "Controlled manipulation of microparticles utilizing magnetic and dielectrophoretic forces." Licentiate thesis, Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-10544.

Full text
Abstract:
This thesis presents some experimental work in the area of manipulation of microparticles. Manipulation of both magnetic and non magnetic beads as well as microorganisms are addressed. The work on magnetic bead manipulation is focused on controlled transport and release, on a micrometer level, of proteins bound to the bead surface. Experimental results for protein transport and release using a method based on magnetization/demagnetization of micron-sized magnetic elements patterned on a modified chip-surface are presented. Special attention has been placed on minimizing bead-surface interactions since sticking problems have shown to be of major importance when protein-coated beads are used. The work with non-magnetic microparticles is focused on the dielectrophoretic manipulation of microorganisms. Preliminary experimental results for trapping and spatial separation of bacteria, yeast and non-magnetic beads are presented. The overall goal was to investigate the use of dielectrophoresis for the separation of sub-populations of bacteria differing in, for example, protein content. This was, however, not possible to demonstrate using our methods.Within the non-magnetic microparticle work, a method for determining the conductivity of bacteria in bulk was also developed. The method is based on the continuous lowering of medium conductivity of a bacterialsuspension while monitoring the medium and suspension conductivities.
APA, Harvard, Vancouver, ISO, and other styles
2

Cailliez, Jonathan. "Contributions à la modélisation et la commande de capteurs de forces actifs pour la méso et micro-robotique." Electronic Thesis or Diss., Sorbonne université, 2020. http://www.theses.fr/2020SORUS278.

Full text
Abstract:
Cette thèse porte sur le développement d’une instrumentation originale et présentant des performances au-delà de l’état de l’art pour la caractérisation et la mesure de forces aux petites échelles. Les travaux présentés couvrent la mesure d’une large gamme de forces mises en jeu en méso et micro-robotique, allant des forces intermoléculaires de l’ordre de quelques µN à des forces de l’ordre du Newton. Le point central réside dans le développement et la mise en œuvre de capteurs basés sur une technologie active particulièrement adaptée pour la caractérisation de forces à gradient variable grâce à une raideur du capteur quasi-infinie en boucle fermée. Trois contributions principales ont été apportées. Sur le plan méthodologique, une nouvelle approche de commande hybride robuste basée sur un placement de structures propre a été proposée et validée expérimentalement dans le cadre de la caractérisation robuste de force d’interaction intermoléculaires en utilisant un microscope à force atomique (AFM). Cette caractérisation a permis de définir les bases du cahier des charges pour la conception et la commande de capteurs actifs mieux a même de caractériser finement les zones instables dans lesquelles les gradients de force sont importants. La seconde contribution réside dans le développement, la conception, la commande et la mise en œuvre d’un capteur actif original de type MEMS (Microsystème électromécanique) ayant la particularité de posséder une caractéristique électromécanique linéaire sur l’ensemble de sa plage de mesure, i.e. +- 20 µN, avec une bande passante supérieure à 2kHz. La troisième contribution réside dans la proposition d’une nouvelle architecture pour la mesure active de forces sur des plages allant du mN au N basée sur un actionnement magnétique et un palier d'air. Ce capteur a été mis œuvre pour la mesure de force magnétique présentant des zones instables lorsque la distance entre la pointe du capteur et l’échantillon magnétique est inférieur à un certain seuil. Les perspectives de cette thèse sont nombreuses en science des matériaux, en biologique et plus généralement en physique. Elle ouvre une nouvelle voie dans la recherche scientifique en microscopie à force atomique active
This thesis focuses on the development of an original instrumentation, with performances beyond the state of the art, for the characterization and the measurement of forces at the small scales. The work covers the measurement of a wide range of forces involved in meso and micro-robotics, from intermolecular forces of the order of a few µN to forces at the Newton level. The focus lies in the development and implementation of sensors based on an active technology particularly adapted for the characterization of forces with a variable gradient thanks to a quasi-infinite sensor stiffness in closed loop. Three main contributions have been made. On the methodological aspect, a new robust hybrid control approach based on Eigen structure assignment has been proposed and experimentally validated for the robust characterization of intermolecular interaction forces using an Atomic Force Microscope (AFM). This characterization has allowed defining the basis of the specifications for the design and the control of active sensors better suited to finely characterize unstable areas in which the force gradients are important. The second contribution lies in the development, design, control and implementation of an original MEMS (Micro-Electro-Mechanical System) type active sensor with the particularity of having a linear electromechanical characteristic over its entire measurement range, i.e. +- 20 µN, with a bandwidth greater than 2kHz. The third contribution lies in the proposition of a new architecture for the active measurement of forces over ranges from mN to N based on a magnetic actuation and an air bearing. This sensor has been implemented for the measurement of magnetic forces with unstable areas when the distance between the sensor tip and the magnetic sample is below a certain threshold. The perspectives to this thesis are numerous in materials science, biology and more generally in physics. It particularly opens a new path in scientific research related to active AFM
APA, Harvard, Vancouver, ISO, and other styles
3

Matope, S., and Der Merwe A. Van. "The application of Van der Waals forces in micro-material handling." Journal for New Generation Sciences, Vol 8, Issue 1: Central University of Technology, Free State, Bloemfontein, 2010. http://hdl.handle.net/11462/554.

Full text
Abstract:
Published Article
This paper investigates the challenges of employing Van der Waals forces in micro-material handling since these forces are dominant in micro-material handling systems. The problems include the creation of a dust-free environment, accurate measurement of the micro-force, and the efficient picking and placing of micro-work pieces. The use of vacuum suction, micro-gripper's surface roughness, geometrical configuration and material type are presented as alternatives to overcome the challenges. An atomic force microscope is proposed for the accurate measurement of the Van der Waals force between the gripper and the micro-work piece.
APA, Harvard, Vancouver, ISO, and other styles
4

Matope, Stephen. "Application of Van-der-Waals forces in micro-material handling." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71608.

Full text
Abstract:
Thesis (PhD)--Stellenbosch University, 2012.
This doctoral dissertation focuses on the application of Van-der-Waals’ forces in micromaterial handling. A micro-material handling system consists of four main elements, which include: the micro-gripper, the micro-workpart, the picking up position and the placement position. The scientific theoretical frameworks of Van-der-Waals’ forces, presented by Van der Waals, Hamaker, London, Lifshitz, Israelachvilli, Parsegian, Rumpf and Rabinovich, are employed in exploring the extent to which these forces could be applied in a micromanufacturing situation. Engineering theoretical frameworks presented by Fearing, Bohringer, Sitti, Feddema, Arai and Fukuda, are employed in order to provide an in-depth synthesis of the application of Van-der-Waals’ forces in micro-material handling. An empirical or pragmatic methodology was adopted in the research. The Electron Beam Evaporation (e-beam) method was used in generating interactive surfaces of uniform surface roughness values. E-beam depositions of copper, aluminum and silver on silicon substrates were developed. The deposition rates were in the range of 0.6 – 1.2 Angstrom/s, at an average vacuum pressure of 2 x 10-6 mbar. The topographies were analysed and characterised using an Atomic Force Microscope and the corresponding rms surface roughness values were obtained. The Rumpf-Rabinovich equation, which gives the relationship of the exerted Van-der-Waals’ forces and the rms surface roughness values, is used to numerically model the results. In the final synthesis it is observed that the e-beam depositions of copper are generally suited for the pick-up position. Aluminum is suited for the micro-gripper and silver is suited for the placement position in an optimised micro-material handling system. Another Atomic Force Microscope was used in order to validate the numerically modelled results of the exerted Van- der-Waals’ forces. The aim was to measure the magnitude of Vander- Waals’ forces exerted by the e-beam depositions and to evaluate their applicability in micro-material handling operations. The measurements proved that Van-der-Waals’ forces exerted by the samples could be used for micro-material handling purposes on condition that they exceeded the weight of the micro-part being handled. Three fundamental parameters, ie: material type, geometrical configuration and surface topography were used to develop strategies of manipulation of micro-materials by Van-der- Waals’ forces. The first strategy was based on the material type variation of the interactive surfaces in a micro-material handling operation. This strategy hinged on the fact that materials have different Hamaker coefficients, which resulted in them experiencing a specific Van-der- Waals’ forces’ intensity during handling. The second strategy utilised variation in the geometrical configuration of the interacting surfaces. The guiding principle in this case was that, the larger the contact area was, the greater the exerted Van-der-Waals’ forces would be In the analytical modelling of Van-der-Waals’ forces with reference to geometrical configuration, a flat surface was found to exert more force than other configurations. The application of the design, for purposes of manufacturing and assembling (DFMA) criteria, also proved that flat interactive surfaces have high design efficiency. The third strategy was based on surface roughness. The rougher the topography of a given surface was, the lesser the Van-der-Waals’ forces exerted were. It was synthesised that in order for a pick-transfer-place cycle to be realised, the root-mean-square (rms) interactive surface roughness values of the micro-part (including the picking position, the micro-gripper, and the placement position) should decrease successively. Hybrid strategies were also identified in this research in order to deal with some complex cases. The hybrids combined at least two of the aforementioned strategies.
APA, Harvard, Vancouver, ISO, and other styles
5

Haliyo, Sinan D. "Les forces d'adhésion et les effets dynamiques pour la micro-manipulation." Paris 6, 2002. http://www.theses.fr/2002PA066529.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Pitt, Ford Charles William. "Unsteady aerodynamic forces on accelerating wings at low Reynolds numbers." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608219.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Van, der Merwe A., and S. Matope. "Manipulation of Van der Waals' forces by geometrical parameters in micro-material handling." Journal for New Generation Sciences, Vol 8, Issue 3: Central University of Technology, Free State, Bloemfontein, 2010. http://hdl.handle.net/11462/574.

Full text
Abstract:
Published Article
This paper explores the manipulation of Van der Waals' forces by geometrical parameters in a micro-material handling system. It was observed that the flat-flat interactive surfaces exerted the highest intensity of Van der Waals' forces followed by cone-flat, cylinder-flat, sphere-flat and sphere-sphere interactive surfaces, respectively. A conical micro-gripper proved to be versatile in manipulating the Van der Waals' forces efficiently in a 'picking up' and 'releasing' mechanism of micro-work parts. It was deduced that the pick-up position should be rough and spherical, and the placement position should be smooth and flat for an effective 'pick-and-place' cycle to be realised.
APA, Harvard, Vancouver, ISO, and other styles
8

Wang, Ji. "Suspended Micro/Nanofiber Hierarchical Scaffolds for Studying Cell Mechanobiology." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/76884.

Full text
Abstract:
Extracellular matrix (ECM) is a fibrous natural cell environment, possessing complicated micro-and nano- architectures, which provides signaling cues and influences cell behavior. Mimicking this three dimensional environment in vitro is a challenge in developmental and disease biology. Here, suspended multilayer hierarchical nanofiber assemblies fabricated using the non-electrospinning STEP (Spinneret based Tunable Engineered Parameter) fiber manufacturing technique with controlled fiber diameter (microns to less than 100 nm), orientation and spacing in single and multiple layers are demonstrated as biological scaffolds. Hierarchical nanofiber assemblies were developed to control single cell shape (shape index from 0.15 to 0.57), nuclei shape (shape index 0.75 to 0.99) and focal adhesion cluster length (8-15 micrometer). To further investigate single cell-ECM biophysical interactions, nanofiber nets fused in crisscross patterns were manufactured to measure the "inside out" contractile forces of single mesenchymal stem cells (MSCs). The contractile forces (18-320 nano Newton) were found to scale with fiber structural stiffness (2 -100 nano Newton/micrometer). Cells were observed to shed debris on fibers, which were found to exert forces (15-20 nano Newton). Upon CO? deprivation, cells were observed to monotonically reduce cell spread area and contractile forces. During the apoptotic process, cells exerted both expansive and contractile forces. The platform developed in this study allows a wide parametric investigation of biophysical cues which influence cell behaviors with implications in tissue engineering, developmental biology, and disease biology.
Master of Science
APA, Harvard, Vancouver, ISO, and other styles
9

Vignaud, Timothée. "Production de forces par le cytosquelette d'actine : mécanismes et régulation par le micro-environnement." Thesis, Grenoble, 2013. http://www.theses.fr/2013GRENY056/document.

Full text
Abstract:
Les travaux présentés se sont intéressés à la régulation des forces produites par le cytosquelette d'actine. Le rôle primordial joué par le microenvironnement a été au centre de nos investigations. L'étude de ces phénomènes a nécessité le développement de techniques innovantes. La première permet le contrôle en temps réel de la forme de la cellule. Elle utilise un laser UV pulsé pour modifier le microenvironnement adhésif de la cellule et contrôler les zones disponibles pour son étalement. La seconde est une amélioration d'une technique existante au sein du laboratoire. Il s'agit de produire des îlots de protéines d'adhésions, de forme contrôlée, sur un substrat déformable d'acrylamide. Ces supports permettent le contrôle de la taille de la cellule et de son organisation interne. En outre, l'élasticité de l'acrylamide permet la mesure des forces générées par la cellule. La dernière technique a combiné le patterning sur acrylamide avec l'ablation laser. Les forces produites au sein d'une structure particulière du cytosquelette ont ainsi pu être estimées. Deux grands mécanismes de régulation des forces ont pu être mis en évidence. L'utilisation de techniques de spectrométrie de masse, de mesure de forces et de biologie moléculaire a permis de mettre en évidence la coopération entre les différents types d'intégrines au niveau de l'adhésion cellulaire. Cette coopération permet un couplage entre l'architecture du cytosquelette et la quantité de moteurs moléculaires mettant en tension ces structures. Ces mécanismes sont primordiaux pour l'adaptation de la cellule à la rigidité de son environnement. Ce sont les structures d'actine qui produisent les forces qui seront transmises au niveau des adhésions. La corrélation entre la taille de ces structures et les forces générées est encore mal caractérisée. La relation entre taille des fibres de stress et répartition des forces au sein de la cellule a pu être étudiée et suggère que la force produite par une fibre de stress augmente avec sa longueur. Une étude systématique de la contractilité des cellules, sur des patterns de différentes tailles, a permis de montrer la relation entre la taille des fibres de stress et la force générée. Une relation biphasique a ainsi été mise en évidence. Quand la taille de la cellule augmente, la force générée au sein des fibres de stress commence par augmenter avant de diminuer au delà d'une longueur critique. Cette longueur correspond également à la taille maximale observée sur des cellules libres de s'étaler sans contraintes. Les résultats obtenus suggèrent que cette chute de force est liée à une augmentation excessive du ratio myosine/actine qui ne permet plus une production de force efficace. Le mécanisme pourrait faire intervenir le désassemblage des structures d'actine par la myosine ou la quantité insuffisante d'actine pour permettre un travail efficace des moteurs moléculaires. La rencontre de ces deux mécanismes permet de définir le champ des possibles pour la cellule en terme de contractilité. Le mécanisme de chute de forces observé n'a pas pu être expliqué à ce jour mais nous travaillons activement pour qu'il le soit dans les mois à venir. Ce phénomène aura sans doute un grand rôle à jouer dans l'intégrité mécanique des tissus et les phénomènes de migration. La chute de force au delà de la longueur critique permet en effet de déstabiliser les adhésions et pourrait être à l'origine de la rétraction de la cellule dans la migration ou du détachement d'une cellule de ces voisines dans le cas d'un tissu sous forte contraintes. Ce détachement protégerait ainsi la cellule d'un déchirement sous l'effet de forces trop importantes
Our work has been focused on the regulation of the forces generated by the actin cytoskeleton. We have more precisely studied the role of the cellular microenvironment in this process. It was necessary to overcome some technical challenges to study these mechanisms. We developed two new techniques. The first one allows for the dynamic control of cell shape. A pulsed UV laser is used to modify the adhesive microenvironment around the cell and to create new area available for cell spreading. The second technique is an improvement of an existing technique from the laboratory. It consists in producing ECM protein islands on a elastic acrylamide substrate. This substrate provides the control of cell shape and internal organization. Plus, the elasticity of the substrate is compatible with traction forces measurements. The last technique combines acrylamide micropatterning and laser ablation of intracellular actin structures. Thus, the forces produced by a particular intracellular structure can be estimated. Two keys mechanisms of force regulation were shown. The use of mass spectrometry, traction force microscopy and molecular biology made it possible to study the interaction between different integrins in the adhesion complex. Cooperation was shown. It allows for the coupling between the architecture of the cytoskeleton and the amount of molecular motors in action. This process is necessary for the adaptation of cell forces to substrate stiffness. Actin structures are the one responsible for force production. This force can then be transmitted to the environment through adhesions.. The link between the length of actin fibers and the force produced was more precisely studied. The results showed a correlation between stress fibers length and the force generated inside it. This was true only above a certain critical value. After that, the force was rather decreasing with increasing fiber length. This critical length corresponds to the maximal length of cell axis on infinite 2D substrate. Our main hypothesis is that a too high myosin/actin ratio will block the proper force production/transmission within the fiber. Disassembly of actin by myosin or limited pool of actin are the two explanations we are currently following. The combination of these two-regulation process put brakes on force production by the cell. Above a certain length, the force produced is decreasing. This decreases in turn the strength of the adhesions anchored to these fibers. This will destabilize the adhesions and causes cell retraction The interplay between the regulation by the adhesion and the production of forces within the fiber set some limits on the level of forces produced by the cell. These processes are likely to be modified in a pathological context and can lead to tumor formation. They also protect the cell from being destroyed by stretching. If the length/stretch is too high, the cell will decrease its forces and detach from neighboring cells. This provide a system protecting the cell from being destroyed by massive deformations within the body
APA, Harvard, Vancouver, ISO, and other styles
10

Alvo, Sébastien. "Étude, modélisation et mesure des forces d'adhésion à l'échelle microscopique." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2012. http://tel.archives-ouvertes.fr/tel-00772533.

Full text
Abstract:
La manipulation d'objets de tailles microscopiques, dont le comportement est régi par des effets de surfaces, nécessite des modèles d'interaction fiables entre les micro-objets et les organes terminaux des robots. De nombreux paramètres entrent en considération dans la modélisation des forces d'adhésion. Il apparaît donc nécessaire de déterminer l'influence de chacun afin de maîtriser en particulier la force à exercer pour séparer deux objets en contact dite force de pull-off. De plus, à l'échelle microscopique, la mesure des efforts d'interaction au cours de la manipulation est complexe et n'est possible que dans certains cas particuliers. L'approche générale proposée dans ce manuscrit repose sur trois étapes. Après une présentation du contexte de ces travaux, la première étape consiste à identifier les modèles et les moyens de mesure de la littérature (chapitre 1). Deux approches sont alors mises en avant pour modéliser les forces de pull-off. Les forces et les faiblesses des modèles sont étudiées plus en détail au chapitre 2 afin de développer, au cours de la seconde étape, un nouveau modèle de force d'adhésion (chapitre 3). Ce dernier met en avant le couplage entre les déformations et les forces d'adhésion et révèle des différences majeures entre les échelles microscopique et nanoscopique. Enfin, l'objectif de la troisième étape est de corréler ce modèle avec des observations expérimentales. L'analyse des résultats expérimentaux effectuée au chapitre 4 montre la difficulté de modéliser des interactions entre des micro-objets réels et met en avant un effet d'échelle s'appliquant aux forces électrostatiques.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "Micro forces"

1

Melis, Matthew E. COMGEN, a computer program for generating finite element models of composite materials at the micro level. [Washington, D.C.]: National Aeronautics and Space Administration, 1990.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

United States. National Aeronautics and Space Administration., ed. COMGEN, a computer program for generating finite element models of composite materials at the micro level. [Washington, D.C.]: National Aeronautics and Space Administration, 1990.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Botswana. Small, Medium, and Micro Enterprises Task Force. Small, Medium, and Micro Enterprises Task Force report. Gaborone: Govt. Printer, 1998.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Seibel, Robin. Manipulation of micro scale particles in an optical trap using interferometry. [Cleveland, Ohio]: National Aeronautics and Space Administration, Glenn Research Center, 2002.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Basnyet, Saroj K. Micro-level environmental management: Observations on public and private responses in Kakani Panchayat. Kathmandu, Nepal: International Centre for Integrated Mountain Development, 1989.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

D, Peterson L., and United States. National Aeronautics and Space Administration., eds. Identification of nonlinear micron-level mechanics for a precision deployable joint. [Washington, DC: National Aeronautics and Space Administration, 1994.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

Réseau Socio-Economie de l'habitat (France). Réhabilitation et embourgeoisement des quartiers anciens centraux: Étude des formes et des processus de micro-ségrégation dans le quartier Saint-Georges à Lyon. Paris: Plan construction et architecture, 1997.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

Bourbia, Fatiha. L'impact des formes urbaines sur le micro-climat et la pérennité constructive des espaces extérieurs: Étude de trois quartiers de Constantine: Souika, Koudiat et Boussouf. 2nd ed. Alger: Office des Publications Universitaires, 2019.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

Fondation Maeght (Saint Paul) (1er avril-25 juin 2001). Joan Miro, métamorphoses des formes: Collection de la Fondation Maeght : [exposition, Saint-Paul, Fondation Maeght,1er avril-25 juin 2001]. Saint-Paul-de-Vence: Fondation Maeght, 2001.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

1939-, Shukla Rohit, ed. Forest and tribal life: Study of a micro-region : socio-cultural traits sustaining tribal ecology, a case study of Danta Taluka, Banaskantha District, north Gujarat. New Delhi: Concept Pub. Co., 1990.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Book chapters on the topic "Micro forces"

1

Haliyo, D. S., Y. Rollot, S. Regnier, and J. C. Guinot. "Micro-Manipulation and Adhesion Forces." In Romansy 13, 265–73. Vienna: Springer Vienna, 2000. http://dx.doi.org/10.1007/978-3-7091-2498-7_28.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Radhakrishnan, Shankar, Harun Solak, and Amit Lal. "In-Channel Flow Sensor Using Drag Forces." In Micro Total Analysis Systems 2001, 179–80. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-010-1015-3_77.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Tamanaha, C. R., D. R. Baselt, P. E. Sheehan, and R. J. Colton. "Fluidics for a Multi-Analyte Detector Based on Intermolecular Binding Forces." In Micro Total Analysis Systems ’98, 407–10. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-011-5286-0_97.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Knospe, Carl R., and Christina Barth. "Actuation of Elastomeric Micro Devices via Capillary Forces." In Advanced Mechatronics and MEMS Devices II, 1–18. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-32180-6_1.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Fajardo-Pruna, Marcelo, Luis López-Estrada, Christian Tutivén, Santos Gualoto-Cóndor, and Antonio Vizán. "Micro Cutting Tool Tip Tracking with a Piezoelectric Matrix." In Proceedings of the XV Ibero-American Congress of Mechanical Engineering, 390–96. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-38563-6_57.

Full text
Abstract:
AbstractIn search of an alternative to micro-milling, a new micromachining technology based on the principles of single-edge cutting has been successfully developed. To have full control of the cutting process, an artificial vision system has been developed, which is able to locate the tip of the cutting tool and thus calculate the forces that develop along the programmed cutting path. As a complementary measuring system, a piezoelectric matrix sensor has been developed that through the composition of the forces in each of the axes of the cutting micro machine can locate the tip of the tool. Preliminary tests yield results that agree with the artificial vision system, the use of this matrix force sensor is a competent complement to the artificial vision system when it does not have the right conditions for its operation.
APA, Harvard, Vancouver, ISO, and other styles
6

Besançon, Gildas, Alina Voda, and Guillaume Jourdan. "Observer-based Estimation of Weak Forces in a Nanosystem Measurement Device." In Micro, Nanosystems and Systems on Chips, 57–84. Hoboken, NJ USA: John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118557815.ch3.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Polycarpou, Andreas A., and Allison Suh. "A Model for Adhesive Forces in Miniature Systems." In Fundamentals of Tribology and Bridging the Gap Between the Macro- and Micro/Nanoscales, 331–38. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-010-0736-8_21.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Kim, Kyung Suk. "Nano and Micro Mechanical Measurement of Interaction Forces Between Solid Surfaces." In Experimental Mechanics in Nano and Biotechnology, 1–4. Stafa: Trans Tech Publications Ltd., 2006. http://dx.doi.org/10.4028/0-87849-415-4.1.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Bello, Shukurat Moronke. "Personality Trait and Innovation Performance of Micro and Small Enterprises." In Leadership, Innovation and Entrepreneurship as Driving Forces of the Global Economy, 663–69. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-43434-6_57.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Daikhin, L. I., and M. Urbakh. "Effect of Electrostatic Interactions on Frictional Forces in Electrolytes." In Fundamentals of Tribology and Bridging the Gap Between the Macro- and Micro/Nanoscales, 199–214. Dordrecht: Springer Netherlands, 2001. http://dx.doi.org/10.1007/978-94-010-0736-8_13.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Micro forces"

1

Wiersma, Diederik S. "Nano photonic - micro robotics (Conference Presentation)." In Complex Light and Optical Forces XI, edited by David L. Andrews, Enrique J. Galvez, and Jesper Glückstad. SPIE, 2017. http://dx.doi.org/10.1117/12.2250568.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Arai, Fumihito, Daisuke Andou, Yukio Nonoda, and Toshio Fukuda. "Micro Manipulation Based on Micro Physics: Micro Pyramids on Endeffector Surface for Attractive Force Reduction." In ASME 1996 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/imece1996-1376.

Full text
Abstract:
Abstract Micro manipulation is required for assembling and maintenance of micro machines and their parts. As the handling objects are miniaturized, attractive forces such as van der Waals force, surface tension force and electrostatic force between micro objects and gripper surface become dominant in the air, and they work as adhesive forces. We cannot neglect such adhesive forces in micro manipulation. We should consider the physical phenomena in the micro world for micro manipulation. So, we propose reduction methods of adhesive forces. Surface roughness of the endeffector surface is effective to reduce the van der Waals force. We propose to make the micro pyramids on endeffector surface by the micromachining techniques. We designed and made a prototype of the micro gripper with the endeffector whose surface is covered with the micro pyramids. Micro pyramids were effective for van der Waals force reduction.
APA, Harvard, Vancouver, ISO, and other styles
3

Cox, Mitchell A. "Structuring light with digital micro-mirror devices." In Complex Light and Optical Forces XV, edited by David L. Andrews, Enrique J. Galvez, and Halina Rubinsztein-Dunlop. SPIE, 2021. http://dx.doi.org/10.1117/12.2584584.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Horodynski, Michael, Matthias Kühmayer, Andre Brandstötter, Kevin Pichler, Yan V. Fyodorov, Ulrich Kuhl, and Stefan Rotter. "Optimal micro-manipulation in disordered media (Conference Presentation)." In Complex Light and Optical Forces XIV, edited by David L. Andrews, Enrique J. Galvez, and Halina Rubinsztein-Dunlop. SPIE, 2020. http://dx.doi.org/10.1117/12.2563881.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Glückstad, Jesper. "Light robotics: new micro-drones powered by light." In Complex Light and Optical Forces XVI, edited by David L. Andrews, Enrique J. Galvez, and Halina Rubinsztein-Dunlop. SPIE, 2022. http://dx.doi.org/10.1117/12.2610754.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Yu, Qin, Bryan Hennelly, and John Healy. "Deriving forces in a single beam gradient force optical tweezers using the angular spectrum method." In Optical Micro- and Nanometrology, edited by Christophe Gorecki, Anand K. Asundi, and Wolfgang Osten. SPIE, 2018. http://dx.doi.org/10.1117/12.2307537.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Melzer, Jeffrey E., and Euan McLeod. "High velocity micro- and nano-particle optical manipulation (Conference Presentation)." In Complex Light and Optical Forces XII, edited by David L. Andrews, Enrique J. Galvez, and Jesper Glückstad. SPIE, 2018. http://dx.doi.org/10.1117/12.2288582.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Shahini, Mohsen, William W. Melek, and John T. W. Yeow. "Characterization of micro forces in pushing flat micro-sized objects." In 2010 IEEE International Conference on Automation Science and Engineering (CASE 2010). IEEE, 2010. http://dx.doi.org/10.1109/coase.2010.5584031.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Armstrong, Declan J., Halina Rubinsztein-Dunlop, Timo A. Nieminen, and Alexander Stilgoe. "Aberration corrected structured light for in-house fabrication of functional micro-structures." In Complex Light and Optical Forces XVII, edited by David L. Andrews, Enrique J. Galvez, and Halina Rubinsztein-Dunlop. SPIE, 2023. http://dx.doi.org/10.1117/12.2657795.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Li, Jiang, Haosheng Chen, and Yongjian Li. "Investigation on Surface Forces Measurement Using Force-Balanced MEMS Sensor." In 2006 1st IEEE International Conference on Nano/Micro Engineered and Molecular Systems. IEEE, 2006. http://dx.doi.org/10.1109/nems.2006.334895.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Micro forces"

1

Goldberg, Linda, and Cédric Tille. Micro, Macro, and Strategic Forces in International Trade Invoicing. Cambridge, MA: National Bureau of Economic Research, November 2009. http://dx.doi.org/10.3386/w15470.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Dudenhoeffer, Donald Dean. Command and Control Architectures for Autonomous Micro-Robotic Forces - FY-2000 Project Report. Office of Scientific and Technical Information (OSTI), April 2001. http://dx.doi.org/10.2172/911031.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Shmulevich, Itzhak, Shrini Upadhyaya, Dror Rubinstein, Zvika Asaf, and Jeffrey P. Mitchell. Developing Simulation Tool for the Prediction of Cohesive Behavior Agricultural Materials Using Discrete Element Modeling. United States Department of Agriculture, October 2011. http://dx.doi.org/10.32747/2011.7697108.bard.

Full text
Abstract:
The underlying similarity between soils, grains, fertilizers, concentrated animal feed, pellets, and mixtures is that they are all granular materials used in agriculture. Modeling such materials is a complex process due to the spatial variability of such media, the origin of the material (natural or biological), the nonlinearity of these materials, the contact phenomenon and flow that occur at the interface zone and between these granular materials, as well as the dynamic effect of the interaction process. The lack of a tool for studying such materials has limited the understanding of the phenomena relevant to them, which in turn has led to energy loss and poor quality products. The objective of this study was to develop a reliable prediction simulation tool for cohesive agricultural particle materials using Discrete Element Modeling (DEM). The specific objectives of this study were (1) to develop and verify a 3D cohesionless agricultural soil-tillage tool interaction model that enables the prediction of displacement and flow in the soil media, as well as forces acting on various tillage tools, using the discrete element method; (2) to develop a micro model for the DEM formulation by creating a cohesive contact model based on liquid bridge forces for various agriculture materials; (3) to extend the model to include both plastic and cohesive behavior of various materials, such as grain and soil structures (e.g., compaction level), textures (e.g., clay, loam, several grains), and moisture contents; (4) to develop a method to obtain the parameters for the cohesion contact model to represent specific materials. A DEM model was developed that can represent both plastic and cohesive behavior of soil. Soil cohesive behavior was achieved by considering tensile force between elements. The developed DEM model well represented the effect of wedge shape on soil behavior and reaction force. Laboratory test results showed that wedge penetration resistance in highly compacted soil was two times greater than that in low compacted soil, whereas DEM simulation with parameters obtained from the test of low compacted soil could not simply be extended to that of high compacted soil. The modified model took into account soil failure strength that could be changed with soil compaction. A three dimensional representation composed of normal displacement, shear failure strength and tensile failure strength was proposed to design mechanical properties between elements. The model based on the liquid bridge theory. An inter particle tension force measurement tool was developed and calibrated A comprehensive study of the parameters of the contact model for the DEM taking into account the cohesive/water-bridge was performed on various agricultural grains using this measurement tool. The modified DEM model was compared and validated against the test results. With the newly developed model and procedure for determination of DEM parameters, we could reproduce the high compacted soil behavior and reaction forces both qualitatively and quantitatively for the soil conditions and wedge shapes used in this study. Moreover, the effect of wedge shape on soil behavior and reaction force was well represented with the same parameters. During the research we made use of the commercial PFC3D to analyze soil tillage implements. An investigation was made of three different head drillers. A comparison of three commonly used soil tillage systems was completed, such as moldboard plow, disc plow and chisel plow. It can be concluded that the soil condition after plowing by the specific implement can be predicted by the DEM model. The chisel plow is the most economic tool for increasing soil porosity. The moldboard is the best tool for soil manipulation. It can be concluded that the discrete element simulation can be used as a reliable engineering tool for soil-implement interaction quantitatively and qualitatively.
APA, Harvard, Vancouver, ISO, and other styles
4

CHRISTENSON, TODD R., TERRY J. GARINO, and EUGENE L. VENTURINI. Precision formed micro magnets: LDRD project summary report. Office of Scientific and Technical Information (OSTI), February 2000. http://dx.doi.org/10.2172/752610.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

O'Hare, Scott M., and James E. Krott. Modeling the Value of Micro Solutions in Air Force Financial Management. Fort Belvoir, VA: Defense Technical Information Center, December 2005. http://dx.doi.org/10.21236/ada443348.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Quate, Calvin F., Leland T. Edwards, and Steve Minne. Sub-Micron Lithography with the Atomic Force Microscope. Fort Belvoir, VA: Defense Technical Information Center, April 1998. http://dx.doi.org/10.21236/ada342660.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Quate, Calvin F. Sub-Micron Lithography with the Atomic Force Microscope. Fort Belvoir, VA: Defense Technical Information Center, May 2000. http://dx.doi.org/10.21236/ada379939.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Haider, Huma. Scalability of Transitional Justice and Reconciliation Interventions: Moving Toward Wider Socio-political Change. Institute of Development Studies (IDS), March 2021. http://dx.doi.org/10.19088/k4d.2021.080.

Full text
Abstract:
Literature focusing on the aftermath of conflict in the Western Balkans, notes that many people remain focused on stereotypes and prejudices between different ethnic groups stoking fear of a return to conflict. This rapid review examines evidence focussing on various interventions that seek to promote inter-group relations that are greatly elusive in the political realm in the Western Balkan. Socio-political change requires a growing critical mass that sees the merit in progressive and conciliatory ethnic politics and is capable of side-lining divisive ethno-nationalist forces. This review provides an evidence synthesis of pathways through which micro-level, civil-society-based interventions can produce ‘ripple effects’ in society and scale up to affect larger geographic areas and macro-level socio-political outcomes. These interventions help in the provision of alternative platforms for dealing with divisive nationalism in post-conflict societies. There is need to ensure that the different players participating in reconciliation activities are able to scale up and attain broader reach to ensure efficacy and hence enabling them to become ‘multiplier of peace.’ One such way is by providing tools for activism. The involvement of key people and institutions, who are respected and play an important role in the everyday life of communities and participants is an important factor in the design and success of reconciliation initiatives. These include the youth, objective media, and journalists. The transformation of conflict identities through reconciliation-related activities is theorised as leading to the creation of peace constituencies that support non-violent approaches to conflict resolution and sustainable peace The success of reconciliation interventions largely depends on whether it contributes to redefining otherwise antagonistic identities and hostile relationships within a community or society.
APA, Harvard, Vancouver, ISO, and other styles
9

Khan, Zaeem A., and Sunil K. Agrawal. Wing Force & Moment Characterization of Flapping Wings for Micro Air Vehicle Application. Fort Belvoir, VA: Defense Technical Information Center, February 2005. http://dx.doi.org/10.21236/ada433708.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Benedek, George, and Alfred H. Casparay. Self-Assembling Biological Springs Force Transducers on the Micron Nanoscale. Office of Scientific and Technical Information (OSTI), August 2016. http://dx.doi.org/10.2172/1299203.

Full text
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Micro forces' for particular source types:
Journal articles Dissertations / Theses Books
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography