Various Types Of Forces Research Articles

A robust force identification method based on L1+2-norm approximation theory

Obtaining the real force of the structure is the basic condition for efficient vibration reduction design. However, the uneasiness and instability of the inverse problem make the force identification still challenging. On the basis of L2-norm regularization, we propose a new method for force identification based on L1+2-norm approximation theory. By introducing the L1-norm penalty operator, a joint norm approximation optimization model is constructed to limit the non-zero force and punish the force value which approaching to zero, so that it can adapt to the identification of various types of forces. Then the optimal force solution is obtained by using the Primal-dual interior point method. Finally, the effectiveness and accuracy of the proposed method are verified by numerical simulation and experiment of asymmetric plate and double-layer plate structures. Different from previous studies, the L1+2-norm method in this work has high robustness, considers the characteristics of sparse regularization and L2-norm regularization, and can adapt to the identification of continuous forces and sparse forces at the same time, which has potential engineering application value.

Forces Governing the Transport of Pathogenic and Nonpathogenic Escherichia coli in Nitrogen and Magnesium Doped Biochar Amended Sand Columns

Background: Access to safe drinking water remains a global issue with fecal indicator bacteria being major pollutants. Biochars offer low-cost adsorbents for bacterial pathogens. A fundamental understanding of how biochars interact with bacterial pathogens is essential to designing effective biofilters. Methods: Water-saturated sand columns amended with Magnesium and Nitrogen-doped biochars produced by pyrolysis at 400, 500, 600, and 700 °C were used to Quantify the transport of pathogenic Escherichia coli O157:H7 and nonpathogenic E. coli k12 strains in porous media. Measured data were modeled using DLVO theory of colloidal stability. were explored. Results: (1) Biochar is hydrophobic while sand and bacteria are hydrophilic; (2) all Gibbs free energy values quantified between E. coli O157:H7 and biochar were negative except for biochar produced at 700 °C; (3) all types of forces investigated (van der Waals, electrostatic, and acid-base interactions) played a role in governing the interactions between bacteria and biochar. Conclusions: (1) Adding doped biochar to sand at a 2% weight ratio enhanced the retention of bacterial cells in the sand/biochar columns; (2) bacterial transport is strain-dependent and mediated by various types of forces resulting from interactions between the various functional groups displayed on bacteria and biochar/sand. Our findings emphasize the importance of monitoring biochar’s functionality to eliminate bacterial pollutants from contaminated water.

OsciHead

Current haptic devices are usually designed to provide one type of force feedback; however, most VR scenarios require versatile force feedback, which may require the integration of different devices to provide various types of forces. In addition, besides the main haptic effects caused by the forces, multiple types of oscillation may also commonly accompany them, which are crucial for improving VR realism and immersion. Therefore, we simulate versatile force feedback by rendering the corresponding types of oscillation as the effects caused by those forces. We take inertia and impact forces as examples in this paper, and achieve versatility using the proposed device, OsciHead, on a head-mounted display (HMD), instead of integrating different devices. By controlling elastic bands' elasticity and stored power, OsciHead uses two rotatable oscillators on both sides of the HMD, in order to render various multilevel and multidimensional oscillation feedback in 2D translation and 2D rotation directions on a head. In an exploratory study, we explored different scenarios in which multiple types of oscillation could be simulated by OsciHead. We then observed oscillation level distinguishability in two just-noticeable difference (JND) studies, and evaluated the oscillation type recognition rates in a recognition study. Based on the results, we performed a VR study, which verified that the inertia and impact feedback simulated by OsciHead enhances realism and achieves versatility.

Comparative Earthquake Resistant Design Study of Thin Rectangular 20 Storey Structure in Zone 1 and Zone 3 Using ETABS

Abstract: An earthquake occurs in the form of seismic waves due to sudden release of energy and results inground shaking. During earthquake, seismic waves propagate through the soil which results in structural damage due to movements within the earth’s crust. It impacts the behavior of interactionof components like building, foundation, underlying soils and also overall system behavior. Whenearthquake occurs, the behavior of a building depends on distribution of mass, strength and stiffness. Generally, the buildings are subjected to various types of forces throughout theirexistence. The forces can be static forces due to dead and live loads and dynamic forces due to earthquake. In this study, the analysis is carried out for seismic response of 20 Storey Commercialoffice building for Zone-I and Zone-III regions through response spectrum method in ETABS. Thedesign details such as reinforcement area for beams, columns and shear walls and resultant parameterslike storey displacement, storey drift, storey shear, base shear, PMM Interaction curves,D/C ratios are observed for specified zones

Stress Optimization of F1 Car Chassis Using FEA Technique

Abstract: Chassis is the primary structural component of an automobile. It is the main supporting structure of a vehicle to which all other systems like braking, suspension and differential are attached. In this project, a methodology for F1 Car chassis design and structural stability analysis is presented. A literature study is carried out to review various existing designs of vehicle chassis, latest innovations and advanced materials used to manufacture the same. The various types of forces and stresses commonly acting on chassis structures are analyzed and their effects on the vehicle are understood. After completing literature study, several findings are listed in a systematic manner, by providing ample arguments to justify each of them. The pro-con analysis is conducted to evaluate merits and demerits of each alternative type of chassis and the material to manufacture it. In this research work, the material are Aluminum Alloy and AISI1144 Carbon steel. Analysis both material in different parameters which are essential for any ideal chasiss such as various types of forces and stresses commonly acting on chassis structures are analyzed and their effects on the vehicle. The most essential design criteria are derived by selecting different materials which then acts as important guidelines during the actual design process. Structural chassis frame is designed as per the design criteria, using the CAD software CATIAV5R19 and the structural stability of the same is tested and analyzed using ANSYS Workbench 19.0 software. From the results of these analysis tests the static structural stability of the design is confirmed. Keywords: Ansys Workbench, Design for Material, Chassis and Carbon Steel.

Study on the self-cleaning phenomenon and anti-pollution flashover performance of micro-nanostructure superhydrophobic coating surface under a high humidity environment

Using micro-nanostructure superhydrophobic coating with the unique self-cleaning phenomenon is a feasible method to further reduce the frequency of insulator pollution flashover. However, the research on the anti-pollution flashover performance of superhydrophobic coating is still insufficient. This paper analyzes the various types of forces on the polluted particles accumulated on the superhydrophobic coating surface, and calculates that the vertical force or the horizontal force on the nano-scale and micro-scale particles is positive when they are in contact with most types of droplets. After being fully wetted, these particles are easily absorbed or pulled by the droplets and leave the coating surface. So it is necessary to establish a new DC pollution flashover mechanism model of superhydrophobic coatings surface from the electric field perspective. Based on this model, the relationship between the pollution flashover voltage and the dry flashover voltage is clarified in the state of extremely small leakage current. Furthermore, the anti-pollution flashover performance experiment was carried out on superhydrophobic coating, RTV coating, and uncoated surface to test the leakage current under different conditions. The experimental results show that at any pollution degree, the leakage current of superhydrophobic coating surface always remains about 16.3μA after being completely wetted.

Deformation behaviour analysis of different offset rim under different loading using finite element method

Finite element analysis was conducted to study the behaviour of the car wheel rim with different offset with different loading condition. The tire in the vehicle is supported by the rim. The wheel and its design and dimensions should be according to a specified tire. This paper, comparative research of different offset rims (positive, negative, or zero offsets) has been investigated under different boundary condition such as load, air pressure. The automobile rims have been designed by using modelling software CATIA and obey the manufacturer standard design and dimension of the vehicle wheel rims. Machine design is the most important factor of industrial operations is used to identify the industrial problem and maintain product quality. The design optimization reduces the risk of damage involved in the industrial process. In this research, ANSYS simulation software is used to identify the various types of forces and stress acting upon the rim. The research shows the use of two different type materials structural steel and aluminium. The final outcome of the overall analysis is present in the form of a graphical representation of maximum stress and maximum displacement at a different type of loading condition. It has been found that the positive offset wheel rim produced high-stress value at 1620 Nm. This concludes the positive offset rim is not good at the high moment. And the central rim and negative offset rim gives the best result. The central rim and negative offset rim has capability sand at a higher moment.

YAP/TAZ Related BioMechano Signal Transduction and Cancer Metastasis.

Mechanoreciprocity refers to a cell’s ability to maintain tensional homeostasis in response to various types of forces. Physical forces are continually being exerted upon cells of various tissue types, even those considered static, such as the brain. Through mechanoreceptors, cells sense and subsequently respond to these stimuli. These forces and their respective cellular responses are prevalent in regulating everything from embryogenic tissue-specific differentiation, programmed cell death, and disease progression, the last of which being the subject of extensive attention. Abnormal mechanical remodeling of cells can provide clues as to the pathological status of tissues. This becomes particularly important in cancer cells, where cellular stiffness has been recently accepted as a novel biomarker for cancer metastasis. Several studies have also elucidated the importance of cell stiffness in cancer metastasis, with data highlighting that a reversal of tumor stiffness has the capacity to revert the metastatic properties of cancer. In this review, we summarize our current understanding of extracellular matrix (ECM) homeostasis, which plays a prominent role in tissue mechanics. We also describe pathological disruption of the ECM, and the subsequent implications toward cancer and cancer metastasis. In addition, we highlight the most novel approaches toward understanding the mechanisms which generate pathogenic cell stiffness and provide potential new strategies which have the capacity to advance our understanding of one of human-kinds’ most clinically significant medical pathologies. These new strategies include video-based techniques for structural dynamics, which have shown great potential for identifying full-field, high-resolution modal properties, in this case, as a novel application.

Notes on Human Nature (Part 7)

Even though our physical world appears to us as a stationary place it is actually filled with motion some of which we can easily see but also many others which are not visible to our eyesight. The space about us appears to be void but its actually a place of various types of forces, energies, particles, waves and others things which are in motion. We simply cannot see these things. Therefore our world is a far more complex place than we have ever imagined. And we have also learned that all these invisible forms of reality are governed by singular laws which apply only to that entity. So the world we live in is not just what we can see with our eyes. There exists many things in our world which are not visible to our eyesight. When we look at 'life' we find something which appears to be a different and separate form of reality. Even though all living things are made out of physical substances life has its own unique characteristics which put it in a different category of existence. Life consists of two things; a physical entity plus something else which is not a part of the physical aspect of life. For one thing life is something which needs to keep feeding itself in order to remain in existence. All forms of life are governed by a program by which each organism passes through a series of stages in its development, its mature stage of existence and finally a period of decline so as to reach a predetermined end to its lifespan. What makes life so different from anything that preceded it is this intelligently designed program which governs its period of existence and then brings it to an end. Life is a temporary event but which also reproduces itself so as to provide a replacement to continue its species. And in the process of reproduction the new organism can be an evolution from the past one so as to adapt to conditions which change over a period of time. Then, on a more advanced level of reality, we come to humanness which consists of a will and a cognitive ability. A human being is therefore a composite of three levels of reality. We are physically made of the substances out of which all things in the universe are made out of. We are also a form of life which means that we are governed by a program which determines the course of our existence. And then, we are endowed with the power to be able to learn, make decisions, create things of our own design and much more.

Design, Motivation and Evaluation of a Full-Resolution Optical Tactile Sensor.

Human skin is capable of sensing various types of forces with high resolution and accuracy. The development of an artificial sense of touch needs to address these properties, while retaining scalability to large surfaces with arbitrary shapes. The vision-based tactile sensor proposed in this article exploits the extremely high resolution of modern image sensors to reconstruct the normal force distribution applied to a soft material, whose deformation is observed on the camera images. By embedding a random pattern within the material, the full resolution of the camera can be exploited. The design and the motivation of the proposed approach are discussed with respect to a simplified elasticity model. An artificial deep neural network is trained on experimental data to perform the tactile sensing task with high accuracy for a specific indenter, and with a spatial resolution and a sensing range comparable to the human fingertip.

Flexible resistive pressure sensor with silver nanowire networks embedded in polymer using natural formation of air gap

A new type of flexible pressure sensor with air gap has been designed based on polydimethylsiloxane (PDMS) and silver nanowires (AgNWs). During fabrication, the interdigitated Ag electrode was fabricated on the bottom PDMS layer by doctor blading and AgNWs were embedded in the top PDMS layer, with a naturally formed air gap between the AgNW layer and the interdigitated electrodes. The thus-formed air gap was controlled by the number of AgNW layers and played an important role in enhancing sensitivity by decreasing the off current in the absence of pressure. The maximum sensitivity of 16.1 kPa−1 was obtained via optimization of the air gap thickness, the AgNW sensing area, and the channel length of the electrodes. The stability of the sensors was confirmed by durability, repeatability, bending, and hysteresis tests. The pressure sensor based on the highly sensitive AgNW network could provide a great opportunity for measuring various types of forces and displacements in wearable devices.

Mechanical positioning of multiple nuclei in muscle cells.

Many types of large cells have multiple nuclei. In skeletal muscle fibers, the nuclei are distributed along the cell to maximize their internuclear distances. This myonuclear positioning is crucial for cell function. Although microtubules, microtubule associated proteins, and motors have been implicated, mechanisms responsible for myonuclear positioning remain unclear. We used a combination of rough interacting particle and detailed agent-based modeling to examine computationally the hypothesis that a force balance generated by microtubules positions the muscle nuclei. Rather than assuming the nature and identity of the forces, we simulated various types of forces between the pairs of nuclei and between the nuclei and cell boundary to position the myonuclei according to the laws of mechanics. We started with a large number of potential interacting particle models and computationally screened these models for their ability to fit biological data on nuclear positions in hundreds of Drosophila larval muscle cells. This reverse engineering approach resulted in a small number of feasible models, the one with the best fit suggests that the nuclei repel each other and the cell boundary with forces that decrease with distance. The model makes nontrivial predictions about the increased nuclear density near the cell poles, the zigzag patterns of the nuclear positions in wider cells, and about correlations between the cell width and elongated nuclear shapes, all of which we confirm by image analysis of the biological data. We support the predictions of the interacting particle model with simulations of an agent-based mechanical model. Taken together, our data suggest that microtubules growing from nuclear envelopes push on the neighboring nuclei and the cell boundaries, which is sufficient to establish the nearly-uniform nuclear spreading observed in muscle fibers.

POLISH MILITARY SECURITY DOCTRINE IN THE YEARS 2004-2014 – SELECTED ASPECTS

In view of today's physical threats, Poland has adopted a new security doctrine. This publication in its assumption intends to outline the thesis on the centralized management and command of the unified military structure, in the context of the systemic approach to our country defense strategy. The study contemplates the Russia's policy, aimed at strengthening its position of a global great power in terms of weakening ties within North Atlantic Treaty Organization, with a particular focus on the regional interests of each of its members. The presented concept of the contemporary army based on joint task forces, characterized by close co-operation of various types of forces and efficient logistics, managed by the modern chain of command, is the major development direction in the field of defense. It is of crucial importance to reorganize our military forces in correlation to the hybrid dimension of contemporary war conflicts.

Role for SUMOylation in disturbed flow-induced atherosclerotic plaque formation

Although atherosclerosis is a multi-factorial disease, the focalization of atherosclerotic plaques on the vessel wall suggests that local factors such as patterns of local blood flow are critical in the progression of atherosclerosis. Blood flow creates various types of forces onto the surface of vascular endothelial cells (ECs). Among those various types of forces, fluid shear stress has a major influence on the structure and function of ECs. At the branch points and the lesser curvature of the aortic arch, blood flow is disturbed (dflow) and atherosclerotic plaques are frequently detected. At the straight parts of the arterial tree and the greater curvature of aortic arch, blood flow is steady (s-flow, high shear stress) and atherosclerotic plaques are rare. These two patterns of blood flow (d-flow and s-flow) affects EC structure and function differently. However, molecular mechanisms underline the difference remains unclear. To provide insights into this question, studies have suggested a number of theories with multiple proposed signaling pathways, and the role of post-translational modifications has emerged. Particularly, SUMOylation is highlighted based on its potentiality to regulate a wide range of cellular functions. EC dysfunction induced by SUMOylation is proposed to accelerate d-flowinduced atherosclerosis. In this review, we focus on SUMOylation and its role in regulating transcriptional networks and propose a mechanistic link between d-flow and EC dysfunction. Since a strong correlation exists between d-flow and atherosclerotic plaque formation, understanding the mechanism of d-flow-induced SUMOylation events may reveal new paths towards therapeutic interventions against EC dysfunction and atherosclerosis.

Elastic Building Blocks for Confined Sheets

We study the behavior of thin elastic sheets that are bent and strained under a weak, smooth confinement. We show that the emerging shapes exhibit the coexistence of two types of domains. A focused-stress patch is subject to a geometric, piecewise-inextensibility constraint, whereas a diffuse-stress region is characterized by a mechanical constraint-the dominance of a single component of the stress tensor. We discuss the implications of our findings for the analysis of elastic sheets under various types of forcing.

Prevalence of Force by Police in Rhode Island Jurisdictions

This article examines the prevalence and severity of police use of force in Rhode Island by reviewing arrest reports from a sample of police departments. The article reports results from 3,300 adult arrests made by officers from 16 police departments that serviced rural, suburban, or urban communities. Force continua measured various types of force by police. Results show that police rarely used levels of force above restraints when arresting suspects. Rhode Island officers used physical force at a lower rate than did officers from other previous surveyed police jurisdictions. Rhode Island officers' reactions of force were mostly commensurate to suspects' actions of resistance during arrests. The authors give special attention to discussing implications that this study's results have for use-of-force training and reporting.

Symbolic algorithms for the computation of Moshinsky brackets and nuclear matrix elements

To facilitate the use of the extended nuclear shell model (NSM), a Fermi module for calculating some of its basic quantities in the framework of Maple is provided. The Moshinsky brackets, the matrix elements for several central and non-central interactions between nuclear two-particle states as well as their expansion in terms of Talmi integrals are easily given within a symbolic formulation. All of these quantities are available for interactive work. Program summary Title of program:Fermi Catalogue identifier:ADVO Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADVO Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Licensing provisions:None Computer for which the program is designed and others on which is has been tested:All computers with a licence for the computer algebra package Maple [Maple is a registered trademark of Waterloo Maple Inc., produced by MapleSoft division of Waterloo Maple Inc.] Instalations:GSI-Darmstadt; University of Kassel (Germany) Operating systems or monitors under which the program has beentested: WindowsXP, Linux 2.4 Programming language used: Maple 8 and 9.5 from MapleSoft division of Waterloo Maple Inc. Memory required to execute with typical data:30 MB No. of lines in distributed program including test data etc.:5742 No. of bytes in distributed program including test data etc.:288 939 Distribution program:tar.gz Nature of the physical problem:In order to perform calculations within the nuclear shell model (NSM), a quick and reliable access to the nuclear matrix elements is required. These matrix elements, which arise from various types of forces among the nucleons, can be calculated using Moshinsky's transformation brackets between relative and center-of-mass coordinates [T.A. Brody, M. Moshinsky, Tables of Transformation Brackets, Monografias del Instituto de Fisica, Universidad Nacional Autonoma de Mexico, 1960] and by the proper use of the nuclear states in different coupling notations. Method of solution:Moshinsky's transformation brackets as well as two-nucleon matrix elements are provided within the framework of Maple. The transformation brackets are evaluated recursively for a given number of shells and utilized for the computation of the two-particle matrix elements for different coupling schemes and interactions. Moreover, a simple notation has been introduced to handle the two-particle nuclear states in ll-, L S J -, and jj-coupling, both in the center-of-well and the relative and center-of-mass coordinates. Restrictions onto the complexity of the problem:The program supports in principle an arbitrary number of shell states with the only limitation given by the computer resources themselves. Typically, the time requirements for the recursive computation of the Moshinsky brackets and matrix elements increase rapidly with the number of the allowed shell states but can be reduced significantly by the pre-calculation of the transformation brackets. Unusual features of the program:Moshinsky brackets are computed and provided in either numeric, algebraic or some symbolic form. In addition, the two-particle matrix elements are calculated for a scalar potential, spin-orbit coupling and tensorial forces, both in floating-point and algebraic notation. All two-particle matrix elements are expressed in terms of the Talmi integrals but can be evaluated also explicitly for several predefined types of the interaction. To simplify the handling of the program, a short but very powerful notation has been introduced which help the user to deal with the two-particle states in various coupling notations. The main commands of the current version of the program are described in detail in Appendix B. Typical running time:The computation of all Moshinsky brackets in floating-point notation, up to ρ = 6 , takes about 5 s at a 2.26 GHz Intel Pentium IIII processor with 512 MB; in algebraic form, the same computations take about 13 s. Similarly, the computation of these brackets up to ρ = 10 requires in numeric and algebraic form about 5 and 15 min, respectively. Once these coefficients have been stored, however, the program replies rather promptly on most further requests.

Structural Phase Transition and Elastic Properties of Thorium Pnictides at High Pressure

We have calculated the structural and elastic properties of thorium mono-pnictides at high pressure, for the first time, using a suitable interionic potential. This method has been found quite satisfactory in the case of uranium compounds, and describes the crystal properties in the framework of ionic model. The calculated equation of state, phase transition pressures for B1 to B2 transition and bulk modulus etc. in the case of all four ThX (X = N, P, As, Sb) compounds agree well with the experimental results. We have also reported the higher order elastic constants and discuss the dominance of various types of forces in them.

Molecules to materials

With the advent of modern physics and chemistry, fundamentally new types of materials have been created in this century. Various types of forces operating in different classes of solids are exploited in the design of molecular materials. A variety of fabrication techniques have been developed to make materials with the desired properties. An overview of these aspects is provided in this article.

Molecules to materials

With the advent of modern physics and chemistry, fundamentally new types of materials have been created in this century. Various types of forces operating in different classes of solids are exploited in the design of molecular materials. A variety of fabrication techniques have been developed to make materials with the desired properties. An overview of these aspects is provided in this article.