Relevant bibliographies by topics / Displacement Forces

Academic literature on the topic 'Displacement Forces'

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Published: 14 March 2023

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Journal articles on the topic "Displacement Forces"

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Sharma, Jyotsna, S. B. B. Inwood, and A. R. R. Kovscek. "Experiments and Analysis of Multiscale Viscous Fingering During Forced Imbibition." SPE Journal 17, no. 04 (November 27, 2012): 1142–59. http://dx.doi.org/10.2118/143946-pa.

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Summary Immiscible displacement of one fluid by another in porous media has practical applications when viscous oil is produced by water injection. A greater understanding of the flow patterns that evolve during such unstable displacements yields insights into improving predictive capability and increasing oil recovery. Immiscible multiphase displacement exhibits a wide range of behaviors depending on the relative magnitude of viscous, capillary, and gravity forces. Using flow-visualization images from forced-imbibition experiments carried out in etched-silicon micromodels, we show that the conventional Darcy-type modeling of fluid flux is not predictive under unstable, immiscible, forced-imbibition conditions at the scale of interest. When a less viscous fluid displaces a more viscous fluid at low capillary numbers, the displacement patterns show viscous instabilities in the form of fingers and local capillary control of interface movement. We show that such complex displacement patterns are well modeled using statistical theories. We derive a scaling model to describe quantitatively the functional forms for saturation, fractional flow, and capillary dispersion profiles using the self-similar characteristics inherent in the displacement patterns. For the specific range of flow rates (Nc ~ 10−7) and oil/water viscosity ratios (M ~ 8–400) considered in our experiments, both capillary and viscous forces are important, and the displacement pattern indicates fractal features. Results show that functional relations of the scaling model are in considerable agreement with our experimental data.
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Wang, Hao, Wen-Zhi Zheng, Jian Li, and Yu-Qi Gao. "Effects of temperature and lead core heating on response of seismically isolated bridges under near-fault excitations." Advances in Structural Engineering 22, no. 14 (June 11, 2019): 2966–81. http://dx.doi.org/10.1177/1369433219855914.

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Seismic responses of bridges isolated by lead rubber bearings under near-fault excitations are presented in this article. A bilinear force-deformation model is employed to represent the hysteretic behaviors of lead rubber bearings. The joint effects of ambient temperature, initial displacement, and lead core heating on the responses of seismically isolated bridges are investigated. Nonlinear time history analyses are conducted with the employed hysteretic models of lead rubber bearings. Comparisons of the responses with and without the joint effects are performed, in terms of maximum isolator displacements, maximum isolator forces, and base forces of the piers. Results show that ambient temperature, initial displacement, and lead core heating have significant joint effects on the responses of seismically isolated bridges. When such joint effects are ignored at low temperatures, the maximum isolator displacements could be overestimated, whereas the maximum isolator forces and the base forces could be underestimated. However, as for ambient temperatures above 20°C, the maximum isolator displacements could be underestimated, whereas the maximum isolator forces and the base forces could be overestimated with small maximum isolator displacements and underestimated with large maximum isolator displacements.
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Fong, Chun-Man, J. Troy Blackburn, Marc F. Norcross, Melanie McGrath, and Darin A. Padua. "Ankle-Dorsiflexion Range of Motion and Landing Biomechanics." Journal of Athletic Training 46, no. 1 (January 1, 2011): 5–10. http://dx.doi.org/10.4085/1062-6050-46.1.5.

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Abstract Context: A smaller amount of ankle-dorsiflexion displacement during landing is associated with less knee-flexion displacement and greater ground reaction forces, and greater ground reaction forces are associated with greater knee-valgus displacement. Additionally, restricted dorsiflexion range of motion (ROM) is associated with greater knee-valgus displacement during landing and squatting tasks. Because large ground reaction forces and valgus displacement and limited knee-flexion displacement during landing are anterior cruciate ligament (ACL) injury risk factors, dorsiflexion ROM restrictions may be associated with a greater risk of ACL injury. However, it is unclear whether clinical measures of dorsiflexion ROM are associated with landing biomechanics. Objective: To evaluate relationships between dorsiflexion ROM and landing biomechanics. Design: Descriptive laboratory study. Setting: Research laboratory. Patients or Other Participants: Thirty-five healthy, physically active volunteers. Intervention(s): Passive dorsiflexion ROM was assessed under extended-knee and flexed-knee conditions. Landing biomechanics were assessed via an optical motion-capture system interfaced with a force plate. Main Outcome Measure(s): Dorsiflexion ROM was measured in degrees using goniometry. Knee-flexion and knee-valgus displacements and vertical and posterior ground reaction forces were calculated during the landing task. Simple correlations were used to evaluate relationships between dorsiflexion ROM and each biomechanical variable. Results: Significant correlations were noted between extended-knee dorsiflexion ROM and knee-flexion displacement (r = 0.464, P = .029) and vertical (r = −0.411, P = .014) and posterior (r = −0.412, P = .014) ground reaction forces. All correlations for flexed-knee dorsiflexion ROM and knee-valgus displacement were nonsignificant. Conclusions: Greater dorsiflexion ROM was associated with greater knee-flexion displacement and smaller ground reaction forces during landing, thus inducing a landing posture consistent with reduced ACL injury risk and limiting the forces the lower extremity must absorb. These findings suggest that clinical techniques to increase plantar-flexor extensibility and dorsiflexion ROM may be important additions to ACL injury-prevention programs.
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Bjarnesen, Jesper. "Between Labor Migration and Forced Displacement." Conflict and Society 2, no. 1 (June 1, 2016): 52–67. http://dx.doi.org/10.3167/arcs.2016.020107.

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The significant number of involuntary returns of labor migrants to Burkina Faso is a relatively neglected aspect of the armed conflict in Côte d’Ivoire. Between 500,000 and 1 million Burkinabe migrants were forced to leave Côte d’Ivoire between 2000 and 2007, placing tremendous pressure on local communities in Burkina Faso to receive and integrate these mass arrivals, and causing those returning labor migrants an acute sense of displacement. Th is article analyzes the experiences of displacement and resettlement in the context of the Ivorian crisis and explores the dialectics of displacement and emplacement in the lives of involuntary labor migrant returnees; their young adult children; and Burkinabe recruits returning aft er their service in the Forces Nouvelles rebel forces in Côte d’Ivoire.
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Gluck, J., Y. Ribakov, and A. N. Dancygier. "Selective Control of Base-Isolated Structures with CS Dampers." Earthquake Spectra 16, no. 3 (August 2000): 593–606. http://dx.doi.org/10.1193/1.1586129.

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Addition of dampers to a base isolator reduces base displacements but may increase floor accelerations and interstory drifts. This paper presents a “selective control approach” for the design of base-isolated active controlled structures with Controlled Stiffness Dampers (CSD). According to this approach the dampers are activated only within a given range of the base displacement. The optimal damping forces are calculated according to structure's displacements and velocities. However, because of the CS dampers' structure the actual application of the forces is independent of the displacement and the velocity that are transferred to the device. These forces depend only on the geometry and on the mechanical properties of the devices' springs. The efficiency of the proposed method is demonstrated in a numerical example.
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Jarosz, Jakub. "The effect of braking forces on displacement of integral bridges." Budownictwo i Architektura 12, no. 2 (June 11, 2013): 023–30. http://dx.doi.org/10.35784/bud-arch.2069.

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The paper presents the results of numerical analyses of the lateral displacement for reinforced concrete and single span integral bridge with foundations constructed on piles. The lateral displacement due to braking forces was analysed. Then, the results were compared to analogical displacement caused by the temperature increase. The following changeable bridge parameters were assumed: span length, deck height, piles length and piles diameter. The results of the lateral displacements were compared on concerning the fixing of the pile top. In the first case, the piles were fixed by pile cap, and in the second one, the piles were fixed directly to the deck. Moreover, two options of soil were considered. The first option in which soil was composed of sand and sandy silt, and the second one in which soil was composed of sand and clay. In the analysed cases, the displacement caused by braking forces accounts for 10% - 20% of the total lateral displacement of the ,construction. The research presented in this paper shows that the main determinants of the lateral displacement of integral bridges are piles diameters and the type of surrounding ground. Pile length is of small importance.
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De Troyer, André, and Theodore A. Wilson. "Mechanism of the increased rib cage expansion produced by the diaphragm with abdominal support." Journal of Applied Physiology 118, no. 8 (April 15, 2015): 989–95. http://dx.doi.org/10.1152/japplphysiol.00016.2015.

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When the abdomen in quadriplegic subjects is given a passive mechanical support, the expansion of the lower rib cage during inspiration is greater and the inward displacement of the upper rib cage is smaller. These changes have traditionally been attributed to an increase in the appositional force of the diaphragm, but the mechanisms have not been assessed. In this study, the inspiratory intercostal muscles in all interspaces were severed in anesthetized dogs, so that the diaphragm was the only muscle active during inspiration, and the displacements of the ribs 10 and 5 and the changes in pleural and abdominal pressure were measured during unimpeded breathing and during breathing with a plate applied on the ventral abdominal wall. In addition, external forces were applied to the 10th rib pair in the cranial and lateral directions, and the rib trajectories thus obtained were used as the basis for a vector analysis to estimate the relative contributions of the insertional and appositional forces to the rib 10 displacements during breathing. Application of the abdominal plate caused a marked increase in the inspiratory cranial and outward displacement of rib 10 and a decrease in the inspiratory caudal displacement of rib 5. Analysis of the results showed, however, that 1) the insertional and appositional forces contributed nearly equally to the increased inspiratory displacement of rib 10 and 2) the decrease in the expiratory displacement of rib 5 was the result of both the greater displacement of the lower ribs and the decrease in pleural pressure.
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Schultheis, Michael J. "Introduction." African Studies Review 32, no. 1 (April 1989): 1–2. http://dx.doi.org/10.1017/s0002020600012750.

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In recent months the international news media has again focused on refugees and internally displaced people in Mozambique, Angola and the Horn of Africa. Many of these are “hunger migrants,” people on the move in search of food. But hunger is only one form of forced displacement. It is clear that drought and famine are the companions of war and civil conflict, which disrupts water supply, planting, harvesting and the patterns of economic life in the countryside. In some instances, this disruption is chosen as the means of warfare carried on against the population.The papers in this symposium develop different aspects of the dynamics of displacement and repatriation. The first paper focuses on forced displacement in Africa, with special consideration of the situation in southern Africa. The second two papers take up the questions of repatriation and reintegration of refugees into their home communities. Together they raise the central issues, which governments and international agencies often are unwilling, or unable, to address.The first paper presents a general overview of the refugee/displacement map in Africa and develops the general thesis that contemporary displacements in Africa, as elsewhere, are caused by economic and political forces which generate oppressive and dehumanizing situations. It evaluates the instruments which the international community has developed to protect refugees and notes the politics of refugee definition. The central thesis analyzes the geo-political forces involved in refugee generation in Africa, specifically in the southern African context. The conclusion looks at implications for collaborative action on the part of the university and nongovernmental communities in both northern and southern countries.
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Huang, Shiping, and Anil Misra. "Path-dependent analysis of elastic sphere contact subjected to tangential loading with varying directions." Proceedings of the Institution of Mechanical Engineers, Part J: Journal of Engineering Tribology 226, no. 8 (March 7, 2012): 678–86. http://dx.doi.org/10.1177/1350650112440414.

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The Cattaneo–Mindlin solutions of contact between elastic spheres and their recent extensions do not consider the sequential application of arbitrarily directed shear forces in the contact tangential plane. For this loading condition, the contact tractions simultaneously undergo loading and unloading. This article presents a path-dependent analysis wherein we use superposition at each loading step to obtain the contact tangential traction, and, subsequently the tangential displacement and compliance. The methodology is illustrated by example calculation of contact shear force–displacement relationship, which shows the formation of hysteretic loop and the noncoaxiality of the shear forces and displacements.
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Zhou, Yanzhou, Ricky D. Wildman, and Jonathan M. Huntley. "Measurement of the mechanical properties of granular packs by wavelength-scanning interferometry." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 466, no. 2115 (November 11, 2009): 789–808. http://dx.doi.org/10.1098/rspa.2009.0297.

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A wavelength-scanning interferometer has been constructed to observe both the normal and in-plane displacements particle by particle at the base of a model granular pack. The pack comprised 25 000 steel beads supported by a thick glass substrate and was subjected to local disturbing forces on its upper surface. The system allows measurement of normal displacements of the beads to a precision of ca 0.1 nm, thereby providing highly accurate determination of contact forces while minimizing artefacts due to substrate and grain compliance. The probability distribution of the normalized contact force was found to be approximately independent of the applied load on the upper surface of the granular pack and has an exponential tail. The probability distributions of the normalized response force and lateral displacement have similar power-law tails. The interactions between contact forces and lateral displacements suggest that significant internal rearrangement occurs in the granular pack as the load is increased, and particle displacement plays an important role in the mechanics of the granular material.
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Dissertations / Theses on the topic "Displacement Forces"

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Guo, Tianle. "Experimental and theoretical studies of the effects of buoyancy forces on liquid/liquid displacement processes in porous media." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq26121.pdf.

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Laskowska, Monika. "A State in Which The Opposing Forces Are Not Equal And Don’t Cancel Out Each Other." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1344798482.

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Makarchuk, Stanislaw. "Measurement of cell adhesion forces by holographic microscopy." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAE034/document.

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Les forces mécaniques, générées par la cellule jouent un rôle crucial dans l'adhésion cellulaire, qui est un processus commun à un grand nombre de lignées cellulaires. Afin de mesurer la champ des forces pendant l'adhérence cellulaire, nous utilisons la microscopie de force de traction, où la cellule adhère à la surface plane d'un substrat souple dans le plan. Les forces sont calculées à partir du champ de déplacement mesuré à l'intérieur du substrat sous la cellule. Nous avons construit le microscope, dans lequel nous utilisons des billes sphériques en polystyrène pour mesurer le champ de déplacement. Les positions des marqueurs sont obtenues en analysant I' image interférentielle des particules. Avec cette technique, nous atteignons une précision nanométrique sur le champ de déplacement des particules, ce qui nous permet d'améliorer la résolution en force de ce type de microscope. Les premières mesures ont été effectuées avec la lignée de cellules cancéreuses SW 480
Mechanical forces, generated by the cell plays crucial role in cell adhesion - common process for different cell lines. ln order to measure the force map during cellular adhesion, we use Traction Force Microscopy (TFM), where cell adheres to the soft substrate in 20 plane, and the forces are calculated from measured displacement field inside the substrate underneath the cell. We built the microscope, where instead of using fluorescent markers, we use spherical polystyrene beads in order to measure the displacement field. Positions of the markers are obtained by analyzing the interference pattern caused by the beads in bright-field light. With this technique, we reach nanometer accuracy of the microsphere position determination, that, respectively, influence accuracy of the calculated force field. With the microscope first measurements were performed with cancer cell line SW 480
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McClellan, Nathaniel Richard. ""An ex vivo model to evaluate the effect of cyclical adductory forces on maintenance of arytenoid abduction after prosthetic laryngoplasty performed with and without mechanical arytenoid abduction"." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1334347534.

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Kabalan, Bachar. "Dynamique des foules : modélisation du mouvement des piétons et forces associées engendrées." Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1126/document.

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Que ce soit dans une rue commerçante, un supermarché ou un aéroport, les phénomènes de foule sont incontournables et nous affecte au quotidien. Elle constitue un système complexe dont la dynamique collective, résultant des interactions individuelles, est difficile à appréhender et a toujours intrigué les scientifiques de différents domaines. Grâce au progrès technologique, il est aujourd'hui possible de modéliser les mouvements de foule et de les reproduire en simulation. Les simulations de mouvement de foule permettent aux chercheurs de plusieurs disciplines, comme les sciences sociales ou la biomécanique, de mieux étudier et comprendre les mouvements des piétons et leurs interactions. Quant aux sciences de la sécurité et du transport, ils y voient des applications concrètes comme le développement de modèles de foule capables de simuler l'évacuation d'un lieu public de moyenne ou de forte affluence, afin que les futures constructions ou aménagements publics puissent offrir une qualité de sécurité et de service optimale pour les usagers. Dans le cadre de cette thèse, nous avons travaillé sur le perfectionnement du modèle discret proposé et développé par l'équipe dynamique du laboratoire Navier. Dans ce modèle, les actions et les décisions de chaque piéton sont traitées individuellement. Trois aspects du modèle ont été traités dans cette thèse. Le premier concerne la navigation des piétons vers leurs destinations. Dans notre modèle, un piéton est représenté par une particule ayant une direction et une allure souhaitées. Cette direction est obtenue par la résolution d'une équation eikonale. La solution de cette équation permet d'obtenir un champ de vitesses qui attribue à chaque piéton, en fonction de sa position, une direction vers sa destination. La résolution de l'équation une fois ou à une période quelconque donne la stratégie du chemin le plus court ou le plus rapide respectivement. Les effets des deux stratégies sur la dynamique collective de la foule sont comparés. Le deuxième consiste à gérer le comportement des piétons. Après avoir choisi son chemin, un piéton doit interagir avec l'environnement (obstacles, topologie, ...) et les autres piétons. Nous avons réussi à intégrer trois types de comportement dans notre modèle: (i) la poussée en utilisant une approche originale, basée sur la théorie des collisions des corps rigides dans un cadre thermodynamique rigoureux, (ii) le passage agressif (forcer son chemin) modélisé par une force sociale répulsive et (iii) l'évitement ``normal'' en adoptant une approche cognitive basée sur deux heuristiques. Les performances des trois méthodes ont été comparées pour plusieurs critères. Le dernier aspect concerne la validation et la vérification du modèle. Nous avons réalisé une étude de sensibilité et validé le modèle qualitativement et quantitativement. À l'aide d'un plan d'expérience numérique nous avons réussi à identifier les paramètres d'entrée ayant les effets principaux sur les résultats du modèle. De plus, nous avons trouvé les différentes interactions entre ces paramètres. En ce qui concerne la validation qualitative, nous avons réussi à reproduire plusieurs phénomènes d'auto-organisation. Enfin, nous avons testé la capacité de notre modèle à reproduire des résultats expérimentaux issus de la littérature. Nous avons choisi le cas du goulot d'étranglement. Les résultats du modèle et ceux de l'expérience ont été comparés. Ce modèle de foule a également été appliqué à l'acheminement des piétons dans la gare de Noisy-Champs. L'objectif de cette application est d'estimer le temps de stationnement des trains dans la gare
Crowds are present almost everywhere and affect several aspects of our lives. They are considered to be on of the most complex systems whose dynamics, resulting from individual interactions and giving rise to fascinating phenomena, is very difficult to understand and have always intrigued experts from various domains. The technological advancement, especially in computer performance, has allowed to model and simulate pedestrian movement. Research from different disciplines, such as social sciences and bio-mechanics, who are interested in studying crowd movement and pedestrian interactions were able to better examine and understand the dynamics of the crowd. Professionals from architects and transport planners to fire engineers and security advisors are also interested in crowd models that would help them to optimize the design and operation of a facility. In this thesis, we have worked on the imporvement of a discrete crowd model developed by the researchers from the dynamics group in Navier laboratory. In this model, the actions and decisions taken by each individual are treated. In its previous version, the model was used to simulate urgent evacuations. Three main aspects of the model were addressed in this thesis. The first one concerns pedestrian navigation towards a final destination. In our model, a pedestrian is represented by a disk having a willingness to head to a certain destination with a desired direction and a desired speed. A desired direction is attributed to each pedestrian, depending on his position from the exit, from a floor field that is obtained by solving the eikonal equation. Solving this equation a single time at the beginning of the simulation or several times at during the simulation allows us to obtain the shortest path or the fastest path strategy respectively. The influence of the two strategies on the collective dynamics of the crowds is compared. The second one consists of managing pedestrian-pedestrian interactions. After having chosen his/her direction according to one of the available strategies, a pedestrian is bound to interact with other pedestrians present on the chosen path. We have integrated three pedestrian behaviors in our model: (i) pushing by using an original approach based on the theory of rigid body collisions in a rigorous thermodynamics context, (ii) forcing one's way by introducing a social repulsive force and (iii) "normal" avoidance by using a cognitive approach based on two heuristics. The three methods are compared for different criteria. The last aspect is the validation and verification of the model. We have performed a sensibility study and validated the model qualitatively and quantitatively. Using a numerical experimental plan, we identified the input parameters that are the most statistically significant and estimated the effects of their interactions. Concerning qualitative validation, we showed that our model is able to reproduce several self-organization phenomena such as lane formation. Finally, our model was validated quantitatively for the case of a bottleneck. The experimental results are very close to the ones obtained from simulations. The model was also applied to pedestrian movement in the Noisy-Champs train station. The objective of the study was to estimate the train dwell time. The simulation results were similar to the observations
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Schmidt, Joachim, and Wolfgang Bechmann. "Zur Anwendung des Skalarprodukts von Kraft und Weg auf reversible Prozesse (Druck-Volumen-Änderung, Dehnung, Elektrostatische Wechselwirkung, Hub) : die Verwendung äußerer oder systemimmanenter Kräfte." Universität Potsdam, 2014. http://opus.kobv.de/ubp/volltexte/2014/6973/.

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Wir schlagen einen allgemein anwendbaren Algorithmus vor, der unter Verwendung des Skalarprodukts von Kraft und Weg zum richtigen Vorzeichen in den Gleichungen für die Arbeit und die Potentielle Energie bei reversiblen Prozessen (Druck-Volumen-Änderung, Dehnung, Elektrostatische Wechselwirkung, Hub)führt. Wir zeigen, dass es dabei möglich ist, systemimmanente oder externe Kräfte zu benutzen. Wir zeigen, dass bei Verwendung von systemimmanenten Kräften das Skalarprodukt mit negativem Vorzeichen anzusetzen ist. Zudem ist es sehr wichtig, nötige Vorzeichenwechsel bei den einzelnen Schritten zu beachten. Wir betonen dies, weil gelegentlich übersehen wird, dass ein Vorzeichenwechsel nötig ist, wenn das Wegdifferential ds durch das Höhendifferential dh beziehungsweise durch das Abstandsdifferential dx oder dr ersetzt werden muss.
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Meier, Amrei [Verfasser]. "Forced Displacement and Development in Host Countries - Resilience as New Concept for Dealing with Situations of Forced Displacement? / Amrei Meier." Bonn : Universitäts- und Landesbibliothek Bonn, 2021. http://d-nb.info/1231911190/34.

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Antonio, Sergio Francisco Dela. "Estudo da sobrecarga dinamica em caminões por meio de medições diretamente no veiculo." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/263951.

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Orientador: Auteliano Antunes dos Santos Jr
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecanica
Made available in DSpace on 2018-08-12T19:38:01Z (GMT). No. of bitstreams: 1 Antonio_SergioFranciscoDela_M.pdf: 2654431 bytes, checksum: a9d019fe7f3a17bc52fb361d8113f727 (MD5) Previous issue date: 2005
Resumo: As cargas dinâmicas que ocorrem em veículos de carga quando estes estão em movimento, são fortemente responsáveis pela deterioração precoce do piso asfáltico das rodovias e logradouros no Brasil. Também são umas das principais responsáveis pelo desgaste excessivo e prematuro dos componentes do veículo. Estes dois fatores fazem com que os custos de transporte rodoviário no Brasil, de mercadorias e bens, fiquem mais elevados. O objetivo deste trabalho é avaliar uma metodologia para medir as cargas dinâmicas que ocorrem em veículos de carga. Na metodologia proposta, utilizou-se a própria suspensão do veículo como parte do sistema de medição, no caso, veículos com suspensão com feixes de molas. O sistema de medida das cargas dinâmicas é composto pelos feixes de molas e um transdutor de deslocamento. Gerou-se a curva de resposta do feixe de molas com relação aos deslocamentos ocorridos através da aplicação das cargas. Após os estudos preliminares, implantou-se este sistema na suspensão dianteira de um veículo de carga de porte médio. Estimaram-se as cargas dinâmicas em várias condições de piso com o veículo carregado, a partir dos deslocamentos medidos. Os resultados mostram que o sistema funcionou satisfatoriamente, e foi possível quantificar os níveis de cargas dinâmicas ocorridas em casos mais críticos. O maior nível encontrado foi de 33,9% acima da carga estática no lado esquerdo da suspensão dianteira, no trecho com lombadas.
Abstract: The dynamical loads and forces occurring in cargo vehicles under movement are among the major causes of the early deterioration on highway and road pavement in Brazil. These dynamical loads are also responsible for the premature and excessive wear on several vehicle components. These two factors combined are among the main reasons why road transportation costs are so expensive in Brazil. The objective of this work is to suggest and evaluate a methodology for measuring the dynamical loads and forces on moving cargo vehicles. This methodology utilizes the suspension system of the vehicle itself as part of the measurement system. In the experimental part of this study a force measuring system was conceived using the leaf spring assembly of the vehicle suspension combined with a simple displacement transducer strategically installed in the vehicle suspension. This force measuring system was installed in a mid-range cargo truck. The characteristic curve of the suspension leaf spring set was determined by the application of static loads onto the vehicle. After calibration and fine adjustments of the system, several experimental runs were performed in the loaded vehicle, measuring the dynamic loads in several pavement types and traffic conditions. The results showed that the system worked satisfactorily, and it was possible to determine the dynamic loads occurred on all experimental runs. The greatest dynamic load found in the field was 33,9 % above the static load on the left front suspension.
Mestrado
Mecanica dos Sólidos e Projeto Mecanico
Mestre em Engenharia Mecânica
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Waterfall, Tyler Lane. "Design of Piezoresistive MEMS Force and Displacement Sensors." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1549.pdf.

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Oswin, Natalie. "Re-framing feminist approaches to forced displacement/refugee discourse." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0021/MQ49420.pdf.

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Books on the topic "Displacement Forces"

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McGhee, D. S. The effect of acceleration versus displacement methods on steady-state boundary forces. Marshall Space Flight Center, Ala: George C. Marshall Space Flight Center, 1992.

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United States. National Aeronautics and Space Administration. Scientific and Technical Information Program., ed. The effect of acceleration versus displacement methods on steady-state boundary forces. [Washington, DC]: National Aeronautics and Space Administration, Office of Management, Scientific and Technical Information Program, 1992.

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Grabska, Katarzyna, and Lyla Mehta, eds. Forced Displacement. London: Palgrave Macmillan UK, 2008. http://dx.doi.org/10.1057/9780230583009.

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Preuß, Hans-Joachim, Christoph Beier, and Dirk Messner, eds. Forced Displacement and Migration. Wiesbaden: Springer Fachmedien Wiesbaden, 2022. http://dx.doi.org/10.1007/978-3-658-32902-0.

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Comissão de Acolhimento, Verdade, e Reconciliac̦ão Timor Leste., ed. Forced displacement and famine. [Dili]: Commission for Reception, Truth and Reconciliation in Timor-Leste, 2005.

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F, Bayefsky Anne, and Fitzpatrick Joan 1950-, eds. Human rights and forced displacement. Cambridge, Mass: M. Nijhoff Publishers, 2001.

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Roots and routes of displacement and trauma: From analysis to advocacy and policy to practice. Oakville, Ontario: Rock's Mills Press, 2015.

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Chully, Arun Antony. Development induced displacement. Bangalore: Centre for Research-Projects, Christ University, 2013.

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1957-, Ota A. B., and Agnihotrī Anitā, eds. Involuntary displacement in dam projects. New Delhi: Prachi Prakashan, 1996.

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Jenny, Robinson, and Open University, eds. Development and displacement. Milton Keynes: Open University in association with Oxford University Press, 2002.

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Book chapters on the topic "Displacement Forces"

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Belzner, Fabian, Carsten Thorenz, and Mario Oertel. "A Modernized Safety Concept for Ship Force Evaluations During Lock Filling Processes." In Lecture Notes in Civil Engineering, 271–80. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-19-6138-0_24.

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AbstractA ship in a lock chamber is exposed to forces acting on the hull during the filling and emptying processes. These forces accelerate the ship and lead to a displacement. To avoid a collision of the ship with the lock structure, it is moored with mooring lines, which can be strained up to a certain breaking load. The force acting in the mooring lines is called the mooring line force and must be distinguished from the ship force. If the mooring line force exceeds the breaking load, the mooring line will fail and the tension energy will abruptly be transformed into kinetic energy. A snap-back of the mooring line ends can produce great forces and the mooring staff is at risk for major injuries. Furthermore, the ship will start to move and could damage the structure and itself. Thus, the mooring line force must be limited during the locking process. The mooring line force depends on the ship force and, furthermore, on the properties of ship and mooring lines. Due to the number of possible parameter combinations the given ship force alone might not be sufficient to judge on the mooring line safety. In this paper a statistical approach to determine the relations between mooring line configuration, mooring line forces and ship force based on Monte Carlo simulations is shown.
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Ullah, Shafi, Bernhard Pichler, and Christian Hellmich. "Modeling Ground-Shell Contact Forces in NATM Tunneling, Based on 3D Displacement Measurements." In Springer Series in Geomechanics and Geoengineering, 293–96. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-32814-5_39.

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Figueroa, C. Alberto, and Christopher K. Zarins. "Computational Analysis of Displacement Forces Acting on Endografts Used to Treat Aortic Aneurysms." In Studies in Mechanobiology, Tissue Engineering and Biomaterials, 221–46. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/8415_2011_73.

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Bedrikovetsky, Pavel, and Gren Rowan. "The Effect of Capillary Forces on Phase Equilibria and Displacement in Porous Media." In Mathematical Theory of Oil and Gas Recovery, 353–70. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-017-2205-6_20.

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Pozovnyi, Oleksandr, Andrii Deineka, and Dmytro Lisovenko. "Calculation of Hydrostatic Forces of Multi-gap Seals and Its Dependence on Shaft Displacement." In Lecture Notes in Mechanical Engineering, 661–70. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-22365-6_66.

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Grabska, Katarzyna, and Lyla Mehta. "Introduction." In Forced Displacement, 1–25. London: Palgrave Macmillan UK, 2008. http://dx.doi.org/10.1057/9780230583009_1.

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Mehta, Lyla. "Why are Human Rights Violated with Impunity? Forced Displacement in India’s Narmada Valley." In Forced Displacement, 201–21. London: Palgrave Macmillan UK, 2008. http://dx.doi.org/10.1057/9780230583009_10.

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Harrell-Bond, Barbara. "Protests Against the UNHCR to Achieve Rights: Some Reflections." In Forced Displacement, 222–43. London: Palgrave Macmillan UK, 2008. http://dx.doi.org/10.1057/9780230583009_11.

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Grabska, Katarzyna, and Lyla Mehta. "Afterword: the Politics of Rights." In Forced Displacement, 244–46. London: Palgrave Macmillan UK, 2008. http://dx.doi.org/10.1057/9780230583009_12.

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Muggah, Robert. "Protection and Durable Solutions: Regimes for Development and Conflict-Induced Internally Displaced and Resettled Populations." In Forced Displacement, 26–49. London: Palgrave Macmillan UK, 2008. http://dx.doi.org/10.1057/9780230583009_2.

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Conference papers on the topic "Displacement Forces"

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Wang, K. C., K. Grant, Q. Sun, L. S. Gan, K. Zareinia, S. Lama, G. R. Sutherland, and Y. Maddahi. "Development of an Instrumented Surgical Setup for Quantifying Displacement and Force in Surgical Dissection." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-52370.

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Knowledge of positional and force properties of surgical dissection in neurosurgery is essential in developing simulation platforms for neurosurgical training such that realistic motion and perception can be conveyed to the trainee during practice. Most proposed models in literature utilize computational techniques to formulate required parameters. However, these models are not realistic enough compared to data obtained from experiments on real brain. Therefore, developing a setup to measure the position, orientation, and interaction forces will help researchers formulate realistic parameters. This paper presents the development of such a setup for quantification of displacements and tool-tissue interaction forces during performance of microsurgical tasks. A bipolar forceps is equipped with a set of force sensing elements to measure the tool-tissue interaction force components. The position and orientation of the forceps tips are measured by attaching a tracker to the bipolar forceps. To show proof-of-concept, an experienced surgeon and one assistant surgeon performed 35 neurosurgical tasks (320 trials) on a cadaver brain (previously-frozen) using the instrumented setup. Positional and force data of the bipolar forceps were recorded during surgical dissection of different brain structures. This paper reports results collected from two microsurgical tasks over 40 trials: dissection of sylvian cistern arachnoid (SCA) and dissection of middle cerebral artery (MCA). Results showed that the mean values of interaction forces during dissection of MCA were smaller than dissecting SCA. The maximum forces observed were 1.94 N and 1.75 N for SCA and MCA, respectively. The application of quantifying such parameters using the developed setup will be in training neurosurgery residents using surgical simulators in which the knowledge of brain tissue parameters is required to formulate the tissue model.
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Wiehn, Joshua S., Michael T. Dugger, and Thomas E. Buchheit. "Measurement of Force and Displacement for the Tribological Analysis of MEMS." In World Tribology Congress III. ASMEDC, 2005. http://dx.doi.org/10.1115/wtc2005-63841.

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The tribological interfaces in microelectromechanical systems (MEMS) pose a significant hurdle in the advancement of MEMS. In order to gain a better understanding of these tribological interfaces, meaningful friction and wear measurements of MEMS devices must be made at loads and speeds relevant to MEMS operation. Devices containing isolated tribological contacts from which quantitative friction forces can be extracted have been developed. Since independent in-plane measurement of forces are not available for structures that are on the order of microns thick, the normal and tangential forces between structures are typically estimated based on the calculation of the force output of electrostatic actuators, and the force required to bend compliant suspensions. We will discuss the uncertainties associated with the measurement of applied and friction forces in MEMS tribometers, and metrology needs for improved tribological analysis of dynamic microsystems. We will also present a method of independent force calibration in these devices, and compare measured output characteristics with those predicted from mechanics and electrostatics.
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Dong, M., and F. A. L. Dullien. "Effect of Capillary Forces on Immiscible Displacement in Porous Media." In SPE Annual Technical Conference and Exhibition. Society of Petroleum Engineers, 1999. http://dx.doi.org/10.2118/56676-ms.

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Lin, Yongliang, Mengxi Zhang, and Xinxing Li. "Evaluation of Seismic Displacement of Quay Walls for the Passive Case Under Earthquake and Tsunami." In ASME 2010 29th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/omae2010-20198.

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Prediction of the seismic rotational displacements of retaining wall under passive condition is an important aspect of design in earthquake prone region. In this paper, a rotating block method is developed to calculate the rotational displacements of quay walls based on rigid foundations under seismic loading and tsunami for the passive earth pressure condition. The proposed method considers the combined effect of the seismic forces, hydrostatic and hydrodynamic forces and tsunami force acting on the quay wall. Variations of different parameters involved in the analysis suggest sensitiveness of the rotational displacement and provides a better guideline for design.
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Zamir, Evan A. "What Forces Does Cell Traction Force Microscopy Measure?" In ASME 2011 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2011. http://dx.doi.org/10.1115/sbc2011-53266.

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It is probably fair to say that the field of cell mechanics emerged with the pioneering work of Harris et al. [1], who observed that cells grown on thin silicone sheets generated wrinkling patterns — unfortunately, quantifying the forces at the cellular level was virtually impossible with their system. Almost two decades later, the study of cell mechanics began in earnest when Pelham and Wang [2] introduced a more rigorous method for quantifying individual cell-generated forces that quickly became known as cell traction force microscopy (CTFM), some form of which is now used in cell mechanics labs around the world. The basic idea underlying the original CTFM method is that the forces generated by cells can be calculated by solving an inverse problem for the displacement field experimentally measured by tracking microspheres embedded in a thin elastic substratum (typically polyacrylamide gel) on which the cells are cultured.
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Kai, Satoru, and Akihito Otani. "Study on Dynamic Alternating Load on Piping Seismic Response." In ASME 2015 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/pvp2015-45287.

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An inertia force resulting from excitation of a structure exposed to ground motion due to an earthquake excites the structure excited and generates a seismic force on the structure. The handling of seismic forces has been being discussed in terms of how the seismic force on a piping controls the deformation of the piping, load-controlled or displacement-controlled. A seismic design code for nuclear facilities applied in Japan qualifies this kind of seismic forces as primary stress components which shall be limited to prevent any plastic collapse, on the assumption that the seismic force mainly consists of load-controlled loads and the deformation due to earthquakes is caused by the loads. On the other hand, theoretically, an inertia force generated from response acceleration under harmonic vibration condition of a structure tends to oppose a response displacement of the structure. Since the inertia force produced from the response acceleration counteracts the response displacement, it is assumed that unstable failures represented by plastic collapse are hardly broken out on such a condition. To figure out the tendency between those forces, several time history analysis using simplified piping models, the vibration characteristic of which were arranged to have various specified natural frequency and specified damping ratio, were performed and the relationship between the element forces which result from response displacements and the inertia forces due to response accelerations have been investigated. The result of this investigation is expected to be useful to improve current seismic design methodology in the future.
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Ajiboye, Damola M., and Matthew R. Maschmann. "Simulating Axial Force at the Substrate of Growing CNT Forests." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-52013.

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A time-resolved carbon nanotube (CNT) forest synthesis model is used to examine the mechanical interactions of actively growing CNT forests. Discrete CNTs in the forest are modeled using linear elastic Euler-Bernoulli beam elements with three degrees of freedom at each node which corresponds to axial displacement, transverse displacement and rotation. The van der Waals force between adjacent CNTs is modeled as linear elastic spring elements and act to locally bond adjacent CNTs in contact. Special consideration is given to the axial forces that arise at the substrate of growing CNTs during the forest growth. While reaction forces are distributed in a spatiotemporal manner, we observe that reaction forces for the slowest growing CNTs are greatest, and in tension, while the fastest growing CNTs experience compressive reaction forces at the substrate.
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Tamura, Ichiro, Shinichi Matsuura, Ryuya Shimazu, and Koji Kimura. "Categorization of Dynamic Loading Into Force-Controlled Loading and Displacement-Controlled Loading." In ASME 2018 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/pvp2018-85098.

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To investigate the behavior of inelastic single-degree-of-freedom systems, the maximum restoring forces and maximum deformations of the systems due to a harmonic excitation are calculated and drawn as a diagram. These systems have restoring forces characterized by bilinear skeleton curve of the kinematic hardening type. The diagram shows two types of characteristics, and the dynamic loadings can be categorized into force-controlled loading and displacement-controlled loading.
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McNeill, Scot, Tomokazu Saruhashi, Ikuo Sawada, Masanori Kyo, Eigo Miyazaki, and Yasuyuki Yamazaki. "A Method for Estimating Quasi-Static Riser Deformation and Applied Forces From Sparse Riser Inclination Measurements." In ASME 2015 34th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/omae2015-41286.

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A method was recently presented for determining quasi-static and dynamic riser angles using measured data typically found in a riser fatigue monitoring system, specifically acceleration and angular rate data. The riser angles were determined at sensor locations. In this paper quasi-static riser displacement, inclination angle, curvature, and stress are estimated along the entire length of the riser, using only the quasi-static inclinations angles at sparse sensor locations. In addition the distribution of applied forces along the entire riser length is also estimated. A rough representation of the current profile can be calculated using the drag coefficients of riser joints. The riser deformation (displacement, inclination, curvature) and applied forces are estimated by solving the matrix equation f = K*x, where f is the vector of forces and moments, K is the stiffness matrix and x is the vector of displacements and inclination angles. In the equation, force and displacement vectors are unknown and the stiffness matrix is determined using Finite Element (FE) modeling. Constraints are applied, setting the inclination angle at the sensor locations to the values derived from measured data. The remaining highly-underdetermined problem cannot be solved in a classical sense, as it admits infinite solutions. To get a solution that is consistent with the physics of riser deformation, smoothness of the solution is enforced as a constraint. The smoothest solution is solved using quadratic programming methods. Following implementation of the method in Matlab®, the procedure was validated using numerical simulations of a riser in applied current. Both connected (to the wellhead) and disconnected cases were simulated. Estimated riser displacements, slopes, curvatures and applied forces are found to match the simulation results closely. The algorithm was then run using measured data from an emergency disconnect event that occurred on the Chikyu drill ship in November, 2012. The riser displacement, inclination and curvature were determined and found to agree well with results determined using another method. The additional capabilities presented herein further expand the utility of a riser monitoring system. Quasi-static and dynamic riser angles are derived from acceleration and angular rate sensors using previously published methods. Using the method developed herein, the quasi-static inclination angles at the sensor locations can be used to determine the displacement, inclination, curvature (stress) and even applied force along the entire riser. These results are particularly useful in strength assessment, model verification, clashing and emergency event reconstruction analyses.
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Steinschaden, Norbert, and Helmut Springer. "Some Nonlinear Effects of Magnetic Bearings." In ASME 1999 Design Engineering Technical Conferences. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/detc99/vib-8063.

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Abstract In order to get a better understanding of the dynamics of active magnetic bearing (AMB) systems under extreme operating conditions a simple, nonlinear model for a radial AMB system is investigated. Instead of the common way of linearizing the magnetic forces at the center position of the rotor with respect to rotor displacement and coil current, the fully nonlinear force to displacement and the force to current characteristics are used. The AMB system is excited by unbalance forces of the rotor. Especially for the case of large rotor eccentricities, causing large rotor displacements, the behaviour of the system is discussed. A path-following analysis of the equations of motion shows that for some combinations of parameters well-known nonlinear phenomena may occur, as, for example, symmetry breaking, period doubling and even regions of global instability can be observed.
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Reports on the topic "Displacement Forces"

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Walston, S. Displacement forces on a neutral current detector from a buoyant and flexible cable under tension. Office of Scientific and Technical Information (OSTI), May 1994. http://dx.doi.org/10.2172/10162473.

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Wang, Wei, Michael Brown, Matteo Ciantia, and Yaseen Sharif. DEM simulation of cyclic tests on an offshore screw pile for floating wind. University of Dundee, December 2021. http://dx.doi.org/10.20933/100001231.

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Screw piles need to be upscaled for offshore use e.g. being an alternative foundation and anchor form for offshore floating wind turbines, although the high demand of vertical installation forces could prevent its application if conventional pitch-matched installation is used. Recent studies, using numerical and centrifuge physical tests, indicated that the vertical installation force can be reduced by adopting over-flighting which also improved axial uplift capacity of the screw pile. The current study extends the scope to axial cyclic performance with respect to the installation approach. Using quasi-static discrete element method (DEM) simulation it was found that the over-flighted screw pile showed a lower displacement accumulation rate, compared to a pitch-matched installed pile, in terms of load-controlled cyclic tests. Sensitivity analysis of the setup of the cyclic loading servo shows the maximum velocity during the tests should be limited to avoid significant exaggeration of the pile displacement accumulation but this may lead to very high run durations.
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Gunay, Selim, Fan Hu, Khalid Mosalam, Arpit Nema, Jose Restrepo, Adam Zsarnoczay, and Jack Baker. Blind Prediction of Shaking Table Tests of a New Bridge Bent Design. Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA, November 2020. http://dx.doi.org/10.55461/svks9397.

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Considering the importance of the transportation network and bridge structures, the associated seismic design philosophy is shifting from the basic collapse prevention objective to maintaining functionality on the community scale in the aftermath of moderate to strong earthquakes (i.e., resiliency). In addition to performance, the associated construction philosophy is also being modernized, with the utilization of accelerated bridge construction (ABC) techniques to reduce impacts of construction work on traffic, society, economy, and on-site safety during construction. Recent years have seen several developments towards the design of low-damage bridges and ABC. According to the results of conducted tests, these systems have significant potential to achieve the intended community resiliency objectives. Taking advantage of such potential in the standard design and analysis processes requires proper modeling that adequately characterizes the behavior and response of these bridge systems. To evaluate the current practices and abilities of the structural engineering community to model this type of resiliency-oriented bridges, the Pacific Earthquake Engineering Research Center (PEER) organized a blind prediction contest of a two-column bridge bent consisting of columns with enhanced response characteristics achieved by a well-balanced contribution of self-centering, rocking, and energy dissipation. The parameters of this blind prediction competition are described in this report, and the predictions submitted by different teams are analyzed. In general, forces are predicted better than displacements. The post-tension bar forces and residual displacements are predicted with the best and least accuracy, respectively. Some of the predicted quantities are observed to have coefficient of variation (COV) values larger than 50%; however, in general, the scatter in the predictions amongst different teams is not significantly large. Applied ground motions (GM) in shaking table tests consisted of a series of naturally recorded earthquake acceleration signals, where GM1 is found to be the largest contributor to the displacement error for most of the teams, and GM7 is the largest contributor to the force (hence, the acceleration) error. The large contribution of GM1 to the displacement error is due to the elastic response in GM1 and the errors stemming from the incorrect estimation of the period and damping ratio. The contribution of GM7 to the force error is due to the errors in the estimation of the base-shear capacity. Several teams were able to predict forces and accelerations with only moderate bias. Displacements, however, were systematically underestimated by almost every team. This suggests that there is a general problem either in the assumptions made or the models used to simulate the response of this type of bridge bent with enhanced response characteristics. Predictions of the best-performing teams were consistently and substantially better than average in all response quantities. The engineering community would benefit from learning details of the approach of the best teams and the factors that caused the models of other teams to fail to produce similarly good results. Blind prediction contests provide: (1) very useful information regarding areas where current numerical models might be improved; and (2) quantitative data regarding the uncertainty of analytical models for use in performance-based earthquake engineering evaluations. Such blind prediction contests should be encouraged for other experimental research activities and are planned to be conducted annually by PEER.
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Davies, Will. Improving the engagement of UK armed forces overseas. Royal Institute of International Affairs, January 2022. http://dx.doi.org/10.55317/9781784135010.

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The UK government’s Integrated Review of security, defence, development and foreign policy, published in March 2021 alongside a supporting defence command paper, set a new course for UK national security and highlighted opportunities for an innovative approach to international engagement activity. The Integrated Review focused principally on the state threats posed by China’s increasing power and by competitors – including Russia – armed with nuclear, conventional and hybrid capabilities. It also stressed the continuing risks to global security and resilience due to conflict and instability in weakened and failed states. These threats have the potential to increase poverty and inequality, violent extremism, climate degradation and the forced displacement of people, while presenting authoritarian competitors with opportunities to enhance their geopolitical influence. There are moral, security and economic motives to foster durable peace in conflict-prone and weakened regions through a peacebuilding approach that promotes good governance, addresses the root causes of conflict and prevents violence, while denying opportunities to state competitors. The recent withdrawal from Afghanistan serves to emphasize the complexities and potential pitfalls associated with intervention operations in complex, unstable regions. Success in the future will require the full, sustained and coordinated integration of national, allied and regional levers of power underpinned by a sophisticated understanding of the operating environment. The UK armed forces, with their considerable resources and global network, will contribute to this effort through ‘persistent engagement’. This is a new approach to overseas operations below the threshold of conflict, designed as a pre-emptive complement to warfighting. To achieve this, the UK Ministry of Defence (MOD) must develop a capability that can operate effectively in weak, unstable and complex regions prone to violent conflict and crises, not least in the regions on the eastern and southern flanks of the Euro-Atlantic area. The first step must be the development of a cohort of military personnel with enhanced, tailored levels of knowledge, skills and experience. Engagement roles must be filled by operators with specialist knowledge, skills and experience forged beyond the mainstream discipline of combat and warfighting. Only then will individuals develop a genuinely sophisticated understanding of complex, politically driven and sensitive operating environments and be able to infuse the design and delivery of international activities with practical wisdom and insight. Engagement personnel need to be equipped with: An inherent understanding of the human and political dimensions of conflict, the underlying drivers such as inequality and scarcity, and the exacerbating factors such as climate change and migration; - A grounding in social sciences and conflict modelling in order to understand complex human terrain; - Regional expertise enabled by language skills, cultural intelligence and human networks; - Familiarity with a diverse range of partners, allies and local actors and their approaches; - Expertise in building partner capacity and applying defence capabilities to deliver stability and peace; - A grasp of emerging artificial intelligence technology as a tool to understand human terrain; - Reach and insight developed through ‘knowledge networks’ of external experts in academia, think-tanks and NGOs. Successful change will be dependent on strong and overt advocacy by the MOD’s senior leadership and a revised set of personnel policies and procedures for this cohort’s selection, education, training, career management, incentivization, sustainability and support.
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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.

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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.
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Gorreck, Michael A. Refugees and Forced Displacement: Challenges for the Military Planner. Fort Belvoir, VA: Defense Technical Information Center, November 2010. http://dx.doi.org/10.21236/ada536667.

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Chiovelli, Giorgio, Stelios Michalopoulos, Elias Papaioannou, and Sandra Sequeira. Forced Displacement and Human Capital: Evidence from Separated Siblings. Cambridge, MA: National Bureau of Economic Research, December 2021. http://dx.doi.org/10.3386/w29589.

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Collyer, Michael, Tahir Zaman, and Dolf te Lintelo. Displacement and Social Assistance. Institute of Development Studies (IDS), February 2022. http://dx.doi.org/10.19088/basic.2022.029.

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Displacement forms part of virtually any major crisis. It introduces a level of complexity when providing social assistance that leads to a specific, usually context-dependent set of challenges. It is widely recognised that the vast majority of displaced people will travel as short a distance as possible to reach safety, whether as Internally Displaced Persons (IDPs), refugees or irregular migrants in neighbouring countries. Displaced people are disproportionately hosted in low- and middle-income countries, and the length of their displacement is increasing. This highlights the urgent priority of displacement; indeed, it has received sustained attention from the highest levels of global decision-making, particularly since 2016, including two Global Compacts in 2018 (Global Compact for Migration, Global Compact for Safe, Orderly and Regular Migration). Although some have argued that such global summits offer a replacement for meaningful action, these events at least highlight clear political will to shift the emphasis from humanitarian responses to a much longer-term development focus. Interest in social assistance and displacement has also grown since 2018 and resulting policy must respond to this concern for more sustainable responses. High-level commitments are slowly filtering through to policy, while recent research has provided clear frameworks for analysing developing policy approaches. Gaps remain in the analysis of policy implementation and in the assessment of how to access social assistance beyond official state channels.
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9

Klugman, Jeni, and World Bank UNHCR Joint Data Center. The Gender Dimensions of Forced Displacement: Findings from New Empirical Analysis. World Bank - UNHCR Joint Data Center on Forced Displacement, December 2021. http://dx.doi.org/10.47053/jdc.141221.

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Abstract:
To date, research and analysis of the gendered dimensions of forced displacement have been limited. This Quarterly Digest highlights findings from a new, major World Bank Research Program which has sought to fill this important gap. The papers published from the Program include eight detailed country investigations and three multi-country studies covering 17 countries, and feature innovative methodological approaches, combining different sources of data to test hypotheses. The Digest presents the results over four main areas of research (poverty, livelihood, intimate partner violence, and gender norms), and concludes with a series of recommendations to improve the collection of data to investigate the intersectionality of gender and displacement. The Program’s findings lend support to a number of expected patterns, like the disadvantages faced by displaced women in economic opportunities, but also reveal some counter-intuitive results in particular settings, underscoring the importance of country-specific analysis.
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10

Shammo, Turkiya, Diana Amin Saleh, and Nassima Khalaf. Displaced Yazidi Women in Iraq: Persecution and Discrimination Based on Gender, Religion, Ethnic Identity and Displacement. Institute of Development Studies, December 2022. http://dx.doi.org/10.19088/creid.2022.010.

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Abstract:
This CREID Policy Briefing provides recommendations to address the marginalisation, discrimination and exclusion faced by displaced Yazidi women in Iraq. Throughout the history of their presence in Iraq, the Yazidis have experienced harassment, persecution, killing and displacement. Most recently, they have been exposed to genocide from the Islamic State (ISIS) group after they took control of Sinjar district and the cities of Bahzani and Bashiqa in the Nineveh Plain in 2014, destroying Yazidi homes, schools, businesses and places of worship. Yazidi people were killed or forced to convert to Islam. Over 6,000 were kidnapped, including over 3,500 women and girls, many of whom were forced into sexual slavery. Men and boys were murdered or forced to become soldiers. Any remaining citizens were displaced. Seven years later, more than 2,000 Yazidi women and children were still missing or in captivity, more than 100,000 Yazidis had migrated abroad, and over 200,000 Yazidi people were still displaced, living in camps.
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