Real Force Research Articles

Quantitative mapping of high modulus materials at the nanoscale: comparative study between atomic force microscopy and nanoindentation.

Local mechanical properties of submicron features are of particular interest due to their influence on macroscopic material performance and behaviour. This study is focused on local nanomechanical measurements, based on the latest Atomic Force Microscopy (AFM) mode, where the peak force set point is finely controlled at each pixel. After probe calibration, we evaluate the impact of spring constant of two AFM hand-crafted natural full diamond tips with steel cantilevers, used for mapping. Based on the fast capture of the cantilever deflection at each pixel and real time force curve analysis in the elastic region, AFM local measured contact moduli mappings of the silica beads (>50GPa) incorporated in an epoxy resin matrix, are compared with those determined using classical instrumented nanoindentation tests. Our analyses show that with the two AFM probes, without local residual deformation, the high moduli of the silica beads measured with this advanced AFM mode are within the standard deviation of the values determined by classical nanoindentation. LAY DESCRIPTION: The knowledge of material properties at the nanometer scale is a key parameter for well understanding and determining the behavior of material at macroscopic scale. In this paper, we compare two methods (an advanced mode and a classical one) based on the analysis of probes in interaction with the surface of studied material. We focus on a latest developed mode for determining local mechanical properties with a very high spatial resolution. For the advanced mode, we also consider two different hand-crafted probes. Our analyses show that with the high spatial resolution advanced mode, local mechanical properties are well determined. We also highlight the impact of the properties of the used probes for this advanced mode. In a final step, the power of the presented investigation lies in the fact that it does not modify the topography of the surface.

Interrogating Naturalness of National Identity

Nation-state has been considered both an intellectual brainchild and a practical offshoot of the European Enlightenment. The liberal philosophy as an intellectual representative of the Enlightenment tradition and the modernists who emphasize modernization as the practical derivative of it not only deliberated on the simultaneousness and coexistence of the two happenings—the rise of national consciousness on the one hand and appreciation for modern values such as equality, liberty and justice on the other, many theorists argued that these modern values could be realized within a nation-state model (a modern institution). Hence, they contributed to naturalization and de-politicization of the nation-state model. Naturalization/secularization of the nation-state idea without deliberating on the possibilities of politicization and construction of national identities legitimize exclusion of people from national space, drives toward homogenization and nation-building process producing refugees and stateless people. Further, nation-states do not feel the urgency in meeting the normative demands of the international order that strive to defend human rights and address the problem of statelessness. In this context, the article seeks to interrogate the naturalness of national identity of individuals by examining the factors that tend to secularize and naturalize it and by unraveling the real socioeconomic forces that engender and shape national identity and help it look the way it does.

Application of Dynamic Sarma Method to Stability Analysis of Rock Slope

In this paper, the shortcoming of Sarma method, a slop safety factor calculation method based on pseudo-static method, are improved by adding real seismic force, calculating acceleration amplification coefficient of each block by using numerical simulation and drawing the time-history of safety factor by using matlab software. The dynamic Sarma method is proposed. Through the calculation of an example, the rationality of the calculation result of slope safety factor by using dynamic Sarma method is verified.

Dividing social networks: Facebook unfriending, unfollowing, and blocking in turbulent political times

ABSTRACT It has been argued that by allowing users to unfriend, unfollow, and block political and cultural ‘others,’ Facebook facilitates the discouragement of dialog between those holding different views on political issues. Using a case study of a civil confrontation in Ukraine, the paper analyzes the reasons for unfriending political ‘others’ reported by 699 respondents of a qualitative survey. Its findings are in line with researchers who have also found that the likelihood of selective avoidance is higher among people who are more politically active, emotionally involved, and who have more online friends. The paper also discusses an interesting discovery that has not been previously considered. The respondents often shunned political ‘others’ out of suspicion that they were trolls. As this paper suggests, whether real or imagined, trolling has turned out to be a real force influencing people’s decisions to withdraw from communication on the most important issues of public life.

Physical Variables Underlying Tactile Stickiness During Fingerpad Detachment.

One may notice a relatively wide range of tactile sensations even when touching the same hard, flat surface in similar ways. Little is known about the reasons for this variability, so we decided to investigate how the perceptual intensity of light stickiness relates to the physical interaction between the skin and the surface. We conducted a psychophysical experiment in which nine participants actively pressed their finger on a flat glass plate with a normal force close to 1.5 N and detached it after a few seconds. A custom-designed apparatus recorded the contact force vector and the finger contact area during each interaction as well as pre- and post-trial finger moisture. After detaching their finger, participants judged the stickiness of the glass using a nine-point scale. We explored how sixteen physical variables derived from the recorded data correlate with each other and with the stickiness judgments of each participant. These analyses indicate that stickiness perception mainly depends on the pre-detachment pressing duration, the time taken for the finger to detach, and the impulse in the normal direction after the normal force changes sign; finger-surface adhesion seems to build with pressing time, causing a larger normal impulse during detachment and thus a more intense stickiness sensation. We additionally found a strong between-subjects correlation between maximum real contact area and peak pull-off force, as well as between finger moisture and impulse.

ABOUT A CORRECT INTERPRETATION OF THE CONNECTION BETWEEN CLASSICAL ELECTRODYNAMICS AND THE SPECIAL RELATIVITY

The purpose of this article is to bring the basic ideas of O. D. Jefimenko to the physical and mathematical community about the physical explanation of some theoretical conclusions of the Special Theory of Relativity. In this paper, we analyze the reality of length contraction and its concrete effect on electromagnetic interactions. We analyze some relativistic “paradoxes” for the concrete material objects and real physical forces, rather than from abstract viewpoint.

Preparation of stable biopolymer composite suspension with metal/metal-oxide nanoparticles

Hydroxypropyl methylcellulose (HPMC) is a kind of biopolymer that is biodegradable, environmentally friendly and possesses exceptional mechanical and tribological properties. Therefore, it could be used as a suitable alternative to plastic. However, HPMC deforms easily when subjected to loads, causing higher real contact area and adhesive force between HPMC and grinding counter. Therefore, HPMC films are easily damaged because of adhesive wear, which negatively affects wear resistance. Hence, nanoparticles (NPs) of Al, Cu, Al2O3 and CuO have been used as fillers to increase the wear resistance of the HPMC composite films. The uniform dispersion of NPs in the suspension is the most important factor, which is greatly related to the wear resistance after film formation. Nanosuspensions with various dispersant concentrations were prepared, and mixed with the HPMC solution to prepare composite solutions and composite films. The results showed that Span 80 could provide steric stabilization, and that it dispersed the NPs effectively in suspension. After mixing the suspension with the HPMC solution, the solution became more stable.

3·1운동 100주년의 대중정치와 한국 민족주의의 현재

This paper aims to analyze ‘popular politics’ and nationalism of Korea with the governmentled project to commemorate the 100th anniversary of the March 1 Movement and anti-Japanese boycott collective action. Firstly I suggest that the Korean nationalism should be viewed not as a singular ideology or a representation system but as a live ideology with a multilayered figure. In other words, nationalism is a real and present force that intersects neoliberalism, populism, division system and combines gender, race and labor. So when discussing Korean nationalism today, we should consider the influence of transnational capitalism and neo-liberal economic effect, and also consider the post-2000s ‘Daehanminguk nationalism’ and its hegemony.BRBased on these, I analyzed the characteristics and orientation of the government-led commemoration project for the centennial of the March 1 Movement. In particular, I argued what ideological effect on the politics of large-scale commemoration and of memory, and what political context they were in, focusing on the activities and discourse of ‘the Presidential Committee for the 100th anniversary of March 1 Movement and the establishment of the Provisional Government’.BRAnd also I examined the process of the mass anti-Japanese boycott movement in 2019 and its cultural politics. The 2016~17 Candlelight Protests created a new mechanism of public activism. I would argue that there is a link between the anti-Japanese boycott movement and the Candlelight Protests, including its limitations and weaknesses. Finally, I looked into the reaction and centrifugal force to the imagination and planning of nationalist popular politics. The main examples were the dissenting views on the nationalist fervor within the liberal/ progress camp amd the context of best-selling book such as “Anti-Japanese Racism”

FEMINISM IN EUROPE: FACING NEW CHALLENGES

The article is devoted to topical issues of the development of the ideology of feminism in modern conditions. The purpose of the work is to identify the factors of the dynamics of the ideology of feminism at the beginning of the 21st century. The main versions of classical feminism are characterized: liberal, Marxist and radical. There is a close connection between the origins of feminism and Marxism, but even in the early period the interaction of these ideological and political movements was problematic. There is also an interaction of feminism with new social movements in the West in the 20th century. The contradictory consequences of the development of the women's movement for the ideology of feminism are noted: on the one hand, the actualization of the feminist agenda in Western countries created the conditions for significant successes in protecting women's rights and recognizing feminism as a real political force, on the other hand, these same successes reduced the relevance of the liberal version of feminism. Recent developments in Europe have a significant impact on the feminist agenda. Globalization and, in particular, the migration crisis of the 2010s are considered as one of the new factors in the ideological dynamics of feminism. The influx of migrants from Muslim countries not only places a burden on state budgets and reduces the level of security of life on the continent, but also erodes the civilizational identity of European society. Muslim migrants do not seek to integrate into European society, often ignore the fundamental values of European civilization, and above all, women's equality. This situation creates incentives not only to renew the political goals of feminists, but also to revise the ideological foundations of their ideology itself. In particular, it is possible to move away from the traditional reliance on left-wing political slogans and replace the popular Marxist phraseology among radical Islamists with values related to the protection of democratic gains of European society.

The effects of design parameters on mechanical failure of Ti-6Al-4V implants using finite element analysis

The failure of dental implant is frequently occurred as the result of mechanical complications under daily biting forces. The long-term stability and the success of a dental implant are highly depended upon developing an implant system having high fracture resistance under cyclic biting forces. The design of implant has a crucial role in improving the fracture resistance of implant by decreasing stress concentration around the implant system. In the present study, three-dimensional (3D) models of the internally connected Ti-6Al-4V implant systems were developed in different dimensions and the failure analysis of these implants was performed under real biting forces according to ISO 14801 using Finite Element Analysis (FEA). In these models, the design parameters (implant diameter, abutment diameter, taper angle of abutment, implant wall thickness, etc.) were optimized in order to prevent the failure of implants in long-term use. The implant model exhibiting the best biomechanical behavior was determined and the stress value was decreased to 170.34 MPa (von-Mises stress) in this implant under cyclic biting loads. Besides the high fracture resistance of this model, longer service life was predicted and relatively smoother stress transmission was achieved from the implant to the bone tissues under biting forces. The implant stability was also increased by optimizing implant tightening torques. Additionally, the mechanical behavior of this implant model was investigated under different biting conditions.

RAND Narratology

“RAND Narratology” looks at the unlikely historical and aesthetic overlap between narrative theory and strategic defense thinking in the middle part of the twentieth century. Looking at the many writings and frankly odd intellectual styles of nuclear war planners working at the RAND Corporation, the essay examines the unexpected play between the material facts of intellectual history, the obscure but nonetheless real force of narrative desire, and the unthinkable costs of nuclear war.

Probabilistic Multiple Pedestrian Walking Force Model including Pedestrian Inter‐ and Intrasubject Variabilities

A probabilistic walking load model that accounts for inter‐ and intrasubject variabilities has been developed to generate synthetic vertical load waveforms induced by pedestrians. The mathematical model is based on a comprehensive database of continuously recorded pedestrian walking forces on an instrumented treadmill, having a wide range of walking frequencies. The proposed model is able to replicate temporal and spectral features of real walking forces, which is a significant advantage over conventional Fourier series models. The load model results in more realistic force time histories than previous models, since it incorporates significant components of the spectra that are omitted in Fourier series approaches. The proposed mathematical model can be implemented in vibration serviceability assessment of civil engineering structures, such as building floors and footbridges, to estimate more realistically dynamic structural responses due to people walking.

Study on ice adhesion of composite anti-/deicing component under heating condition

An anti-/deicing component of composite materials for wind turbine blades is usually carried out under heating conditions. In order to study the ice adhesion properties of composite anti-/deicing component under heating conditions, an experimental platform for measuring ice adhesion force on composites was set up. Based on the heating parameters such as the heating temperature, heating voltage, and heating time, the experiments of ice adhesion of composite anti-/deicing component under deicing conditions were designed by orthogonal analysis. In this article, ice adhesion forces on composite anti-/deicing component were measured at −9.74°C, −11.58°C, −14.1°C, and −16.84°C by the proposed experiment platform, and the real ice adhesion forces under various heating parameters were measured. Through the analysis of experimental data and fitting method, the relationship between various factors and ice adhesion on composite anti-/deicing component was expounded. The influence weight of each heating parameter on the ice adhesion was analyzed. In addition, the mathematical model of ice adhesion on composite anti-/deicing component under deicing condition was established to describe the influence of deicing variables on ice adhesion in the experiments. According to the fitting function of the experimental data, the relationship between the heat consumption of composite anti-/deicing component and ice adhesion force in the process of heating is in accordance with the inverse power exponential expression, which reveals the internal relationship between ice adhesion force and energy consumption.

Overcoming University Students’ Alternative Conceptions in Newtonian Mechanics

Students’ alternative frameworks and prior conceptions about interactions forces «traditionally, known as Newton's third law» have been largely investigated. The various investigations clearly show that students very often fail to apply Newton’s laws of motion in general to everyday situations and third law in particular. This study highlights some of the serious difficulties students undergo with reciprocal interactions and circular motions, taking advantage of previous studies and/or surveys we managed to reveal and identify a wide range of misconceptions among students, enabling teachers to set appropriate strategies to overcome them. Closely related to students’ misconceptions in Newton’s law of motion, there are still serious difficulties facing students to differentiate between real and fictitious forces, especially when tackling dynamics problems involving circular motion. An approach to teaching mutual interactions and the meaning of centripetal force is suggested that focuses on reconsidering and/or refining students' intuitive thinking on the nature of mutual interactions. However, the essence of this argument is that the teaching of science is not a process by which the wrong ideas are substituted by the correct ones; but students should know where they went wrong and why.

Current Trends in Norwegian Education Reform

The reform of the Ukrainian education system is one of the key tasks of modern national policy, as a result of which the issue of considering and borrowing positive foreign educational experience is updated, which determines the relevance of scientific research. The purpose of the work is to analyse and identify the characteristic features of the process of development and modernisation of the Norwegian educational system. In the study, the author used a number of general scientific theoretical research methods, in particular, the analysis and synthesis of scientific and methodological literature, and the comparison and generalisation of the developed source base. The paper deals with the problem of analysing the current educational reform in Norway. It was established that the country belongs to the leading developed countries in the field of educational policy, and its level is an important factor in intellectual, economic, social, scientific and technical, innovation, technological, and cultural development. The main reasons and consequences of reforming the Norwegian educational space are substantiated. The author’s vision of Norway s educational reform is presented. It was determined that focusing on the modern labour market, Norwegian education priorities today include: the ability to operate with innovative technologies and knowledge; a combination of conventional and alternative education, public and private; increasing the role and importance of education in the life of society, turning it into a real production and social force, the central connecting link of the system “science – technology – man – production – culture”. The practical value of the paper lies in the structural analysis of the Norwegian experience of reforming the educational system, which allows reviewing the problematic aspects of Ukrainian education and find relevant methods for solving them

Захист прав органів місцевого самоврядування в Україні: теоретико-правові засади

The article considers the theoretical and legal principles of protection of the rights of local governments, which is due to the public law status of local governments. When addressing the topic of protection of the rights of local governments, attention is focused on the need to develop clear criteria for distinguishing between the categories of "guarantees", "provision", "protection" and "protection", which will solve the urgent problem of improving the implementation of tasks, functions and powers. . To this end, the task is to clarify the concept of "protection of the rights of local governments", to establish conditions that would prevent any violation of the rights and legitimate interests of local governments. It is established that local governments play an important role in the life of every citizen, in legal relations with the inhabitants of the territorial community, so they must be quickly and effectively implemented in actual social relations, because today the implementation and protection of local government is the priority of any democracy. It is proved that the state should create the necessary mechanism for protection of the rights of local self-government bodies, which will have real force to solve the problem of offenses at the local level. As a result of the study, it was noted that the protection of the rights of local governments is the exercise by local governments of the right to protection by applying by the authorized body any means (measures) of protection not prohibited by law to stop violation, restoration or recognition of violated or disputed rights. proper exercise of local rights by local governments.

Nigeria’s ‘Quadrilemma’: Globalization, State Delegitimization, Religious Fundamentalism and Insecurity

This paper examines the forces that have animated insecurity in Africa/Nigeria via the instrumentality of religious fundamentalism. Drawing data mainly from secondary sources, and leaning on social contract theoretical framework, it argues that contrary to the conventional wisdom that Boko-Harm-styled insecurity in Nigeria is fuelled by religious fundamentalism, the real force lies in neo-imperialism masquerading as globalization.To be sure, this global phenomenon though the mechanism of market reforms has further delegitimized and deconstructed the state in Africa. Put differently, it has alienated the state not only from itself but has also succeeded in alienating it from the citizens. With the alienation of the Leviathan from the society, sub-state actors step in to fill the vacuum. This is where ethnic and religious militias come into the picture.The paper submits that remediation lies in the decolonization and the restructuring of the state via the instrumentality of process-led constitution-making.

Shanghai Cooperation Organization: A Realist Approach

The main goal of this paper is an analysis of activities, purposes, problems of the (SCO) since its inception in order to understand what is the main reason behind its creation and existence? What are its achievements and what benefits have got each member state? Is it beneficial to all members? The hypothesis is that SCO serves only its big members, it was intended to be a China’s tool to enter Central Asia without vexing Russia. The article analyzes the activities of the SCO with the existing theories in IR in order to answer these questions. The main objective of the SCO was an attempt by the powers of the Central Asia to control the region. The SCO faces problems of distrust between its members. It is a very important instrument of guaranteeing Sino-Central Asian partnership. It is also a guarantee that China will never dominate Central Asia due to many signed agreements within the organization. With more than twenty years of history and existence, the SCO may become a real force on the international arena. The SCO’s intention is to become a world power and to construct a fairer international order. The SCO has the economic potential and political will to do it.

Physics of Gyroscope’s “Antigravity Effect”

The physics of gyroscopic effects are more complex than presented in existing mathematical models. The effects presented by these models do not match the real forces acting on gyroscopic devices. New research in this area has demonstrated that a system of inertial torques, which are generated by the rotating mass of spinning objects, acts upon a gyroscope. The actions of the system of inertial forces are validated by practical tests of the motions of a gyroscope with one side support. The action of external load torque on a gyroscope with one side support demonstrates that the gyroscope’s upward motion is wrongly called an “antigravity” effect. The upward motion of a gyroscope is the result of precession torque around its horizontal axis. The novelty of the present work is related to the mathematical models for the upward and downward motions of gyroscopes influenced by external torque around the vertical axis. This analytical research describes the physics of gyroscopes’ upward motion and validates that gyroscopes do not possess an antigravity property.

Real time cable force identification by short time sparse time domain algorithm with half wave

In the fatigue damage analysis of cables, it is very important to understand the cable force history. However, most current cable force identification methods are based on the average cable force assumption. To overcome this issue, this paper proposes the short time sparse time domain algorithm combined with the simplified half wave method (STSTD + SHW). This method only requires one acceleration sensor and is thus simple, economical, convenient, and fast. Its reliability and accuracy were verified by two experiments and one engineering application. According to the results, this method does not only reduce the influence of the boundary conditions on cable force identification but can also quickly identify the dynamic cable force. Moreover, only one accelerometer is required to avoid the problem of sensor placement and optimization, which is conducive to practical engineering applications.