Independent Force Research Articles

Growth and population structure of bloody cockles Senilia senilis at Banc d’Arguin and Bijagós with different environmental conditions and harvesting regimes

In addition to density-dependent (i.e. food availability) and independent (i.e. abiotic gradients) forces, size-selective harvests of organisms often induce changes to their life history, demography, and reproduction. Shellfish are increasingly overexploited worldwide, and the effect of size-selective harvest on their populations is unclear. The African bloody cockleSenilia senilisis a dominant bivalve in most West African coastal systems, where it is an important source of protein. Here, we studied its population structure (abundance, biomass, and size) and life history traits (age, annual growth rate, and size for age) under contrasting harvesting conditions at the 2 largest intertidal systems in the region: the Bijagós archipelago in Guinea-Bissau (harvested) and Banc d’Arguin in Mauritania (unexploited). To account for local ecological context, we assessed environmental variables that could also affect the abundance and size ofS. senilisat these sites. We found that theS. senilispopulation at Bijagós is significantly denser and older, with lower standing biomass and smaller-sized shells than the population from Banc d’Arguin. In Bijagós, the annual growth is 3-fold lower, and the size-for-age is half of that at Banc d’Arguin. At both sites,S. senilisdensities and sizes were correlated with habitat quality indicators: mangrove and mudflat productivity at Bijagós and seagrass and sediment characteristics at Banc d’Arguin. The smaller-sized mature individuals, denser populations, and lower standing biomass at Bijagós compared to Banc d’Arguin are indications of considerable size-selection pressure at Bijagós.

Land and the Language of Race: State Colonization and the Privatization of Indigenous Lands in Araucanía, Chile (1871–1916)

AbstractThis article explores the vision, process, and reaction to the privatization of Mapuche lands in Araucanía, Chile, from 1871 to 1916. It shows how politicians developed a racial vision for Araucanía between 1871 and 1882 during the final battle with independent Mapuche forces. Chilean government officials and elite societies created land policies that targeted the removal of indigenous populations from fertile lands to expand industrial agriculture by favoring large Chilean-owned estates and partitioning small to medium-sized plots to European settler-farmers. From 1883 to 1896, the Chilean government put its vision into practice, investing in the recruitment of European farmers and reconsidering new laws regarding colonization, land rights, and indigenous settlements. However, after the 1891 civil war, the government retreated from expensive state-building projects. From 1896 to 1916, Chilean small farmers intensified land grabs and, in response, indigenous communities formed organizations to defend their lands. At the core of the conflict were the issues of land and racialized policies that defined land access. By examining laws, government reports, missionary chronicles, and indigenous writings, this article demonstrates the progression of a racialized language that excluded indigenous peoples from their lands, founded in the desire to privatize native lands and accelerate the making of a modern Europeanized nation.

ТРАНСНАЦІОНАЛЬНІ ВАЖЕЛІ ГЛОБАЛІЗАЦІЇ: ТЕОРЕТИКО-МЕТОДОЛОГІЧНИЙ АСПЕКТ

The article is devoted to the scientific view’s systematization on the globalization’s processes and forms in the context of the role of the levers of transnationalization in ensuring global economic development. It was established that modern socio-economic changes that take place in the world indicate the formation of systemic manifestations of interconnection and interdependence at the global level. In the conditions of strengthening globalization processes, not only the global space is being formed, but also the corresponding global mechanisms that regulate their activities are developing: the formation of the global labor market, global scientific and educational space, etc. Based on the systematization of scientific views on the processes and forms of globalization, the multivariate approaches to the interpretation of this concept are defined. It is emphasized that modern theories and concepts of the globalization processes’ development rely on various aspects of the countries’ inclusion in global processes and structures. It is emphasized that today there are signs of transformation of the existing globalization paradigm. This is because of the fact that existing economic theories do not cover the latest trends of non-linear development of globalization processes - manifestations of hyperglobalization (expansion of social processes into new forms of spatiality) and deglobalization (reduction of spatiality of social processes). It was determined that the processes of economic activity’s transnationalization play a special role in the development of globalization: globalization, that creates prerequisites and incentives for the development of intra-sectoral international division of labor, also led to the creation of powerful transnational corporations as an independent economic force. It is substantiated that at the current stage, not only the global space is being formed, but also the corresponding global mechanisms that regulate its functioning is also forming. A prominent place among them belongs to the processes of transnationalization. The dominant role of TNCs is accompanied by the formation of systemic relationships and interactions, the essential understanding of which is a condition for the equal inclusion of national economies in the world economy. Key words: globalization, transnationalization, internationalization, global sociality, transnational corporations, transnational interactions.

ПЕРІОДИЗАЦІЯ УКРАЇНСЬКО-ПОЛЬСЬКИХ ВІДНОСИН У ГАЛИЧИНІ ЗА АВСТРІЇ: НАЦІОНАЛЬНІ ЗМАГАННЯ, СПІВПРАЦЯ І ПОШУКИ ЗГОДИ

The author distinguishes five historical stages in the development of Ukrainian-Polish socio-political, cultural, educational, and literary relations in sub-Austrian Galicia in the nineteenth and early twentieth centuries. The first stage is from the beginning of the Austrian annexation of Galicia (1772) to the eve of the revolution (February 1848). For the Galician-Ruthenian leadership, it was a stage of national and cultural revival that lasted from the beginning of the nineteenth century. For the Polish leadership, it was a political and conspiratorial stage of the national liberation struggle to restore the recently lost statehood. The second stage is from the revolutionary Spring of Nations (March 1848-1849) to the end of the reactionary era (1850-1859). In 1848-1849, Polish revolutionary writers published numerous propaganda works in Ukrainian (political poems, messages, fables, poems, short stories, letters, appeals, and articles) in brochures or in periodicals of the time, calling on Galician “Ruthenians” to support the Polish struggle against the Austrian enslavers. However, the church and cultural and educational leadership of the “Ruthenians” acted as a self-sufficient and independent political force, part of the entire Ukrainian people, loyal to the Habsburg monarchy. Later (1894), V. Budzynovskyi and M. Pavlyk condemned the Austrophilic loyalty of the “Rusyns” of that time, while Ivan Franko justified it. Signed at the Slavic Congress in Prague on June 7, 1848, the agreement between Galician Ukrainians and Poles (the first under Austrian rule) on an autonomous Ukrainian-Polish federation in Galicia (within the Austrian Empire) theoretically laid down the most optimal and promising foundations for Ukrainian-Polish understanding, cooperation, and equal coexistence in the region, but was not implemented. The third stage covers the era of reforms: from the beginning of constitutional experiments in the Austrian Empire to the transformation of Galicia into a disproportionate Polish-Ukrainian autonomy (1859-1873). Attempts at Ukrainian-Polish rapprochement were renewed: the governor of Galicia, A. Goluchowski tried unsuccessfully to legalize the conversion of Ukrainian spelling from Cyrillic to Latin (1859-1861), financed the newspaper “Rus” (1867), and the vice-marshal of the Galician Provincial Sejm, Yu. Lavrovskyi, and other Galician-Ruthenian ambassadors initiated the Polish-Ukrainian agreement of 1869-1871 based on a program of 32 articles, which, however, was not adopted in the Sejm. The situation in Austrian-Polish-Ukrainian relations in Galicia changed to the opposite: in 1848-1849, the Austrian authorities fought the Polish nobleman’s revolutionary movement, gaining the loyalty of most Galician Ukrainians, and in 1867-1873, on the contrary, the conservative Polish nobility reached an agreement with the Austrian authorities and achieved national and territorial autonomy for Galicia under Polish domination. Under these conditions, the fourth stage (1890-1897) continued. From the late 1870s to the mid-1890s, a new phenomenon was the attempts at cooperation and interaction between Ukrainian (I. Franko, M. Pavlyk, and others) and Polish socialists in Galicia. The most successful attempts at Ukrainian-Polish political agreement and cultural and educational cooperation in Galicia end this stage with the “New Era” of national democrats O. Barvinskyi and Y. Romanchuk and the stadtholder of Galicia K. Badeni (1890-1894), as well as the “New Course” of O. Barvinskyi (1895-1897). The fifth stage lasted from the aggravation of the Ukrainian-Polish confrontation as a result of the bloody parliamentary elections in March 1897 to the beginning of the collapse of the Austro-Hungarian Empire (October 1918). Under the threat of Ukrainian-Austrian understanding due to the government’s support for Ukrainians, the stadtholder of Galicia A. Potocki negotiated with Ukrainian national democrats (primarily the head of the Ukrainian club in the Galician Sejm, E. Olesnytskyi) in 1907-1908, but their agreements were nullified by a terrorist attack by a student of the University of Vienna, a social democrat, M. Sichynskyi. Under the leadership of the new stadtholder of Galicia, M. Bobrzynski, a Polish-Ukrainian compromise draft of the reform of elections to the Galician Sejm (1913) was developed, but due to the protests of the Polish opposition minority and Muscophiles, Bobrzynski resigned. Under the new stadtholder of Galicia, V. Korytowski, and the decisive role of Greek Catholic Metropolitan Andrey Sheptytskyi, the Galician Sejm in 1914 adopted a reform of the provincial statute and the introduction of a new electoral order to the Sejm. This law (the so-called Galician Equalization) opened up historical opportunities for Ukrainian-Polish dialogue and reconciliation that were unimaginable until then, but were not realized due to the outbreak of World War I.

Analysis and design method of a class of reconfigurable parallel mechanisms by using reconfigurable platform

This paper proposes a method to design reconfigurable parallel mechanisms by applying reconfigurable platforms. According to the requirements of convenience and reliability, the basic rules for designing a reconfigurable platform are proposed. Based on a planar four-bar mechanism, single- and double-stage mechanisms are designed based on DOF (Degree of Freedom) formulation, and the single- and multi-loop reconfigurable platforms are both presented. For the spatial reconfigurable platform, the F1 (one independent force), C1 (one independent couple), F2C1 (two independent forces and one independent couple), and F1C2 (one independent force and two independent couples) over-constrained mechanisms are designed according to screw theory. To meet the multi-limb, parallel-mechanism structural requirement, single-loop over-constrained mechanisms are developed to multi-loop over-constrained mechanisms. Finally, a typical reconfigurable parallel mechanism is selected. Both the kinematics and performance analysis are investigated, and dimension synthesis based on multi-objective optimization is explored using some global indices.

Philosophical-Linguistic Analysis of the Idea of Freedom

In recent decades, ideal factors have become an independent force for the implementation of social transformations. At the same time, the question remains debatable, what caused the change in the original meanings and, as a result, the unequal implementation of social ideas in practice. The methodology of linguistic analysis is considered. The importance of considering contextual realities for a more valid understanding of the transformation of the content of social ideas is determined. Changes in the meanings of the idea of freedom are analyzed. It is revealed which maxims were the cornerstones of English, American, French and Russian theorists. It is shown how the aspirations of actors can limit the imp­lementation of freedoms in practice, depending on general social needs.

Desa Tangguh Penyakit Mulut Dan Kuku (PMK) Berbasis Peternakan Rakyat

Foot and Mouth Disease (FMD) in Bukek village is an alarming condition considering that Bukek village is a strategic area for the distribution of livestock between regions in Tlanakan district. The need for treatment from this point in the prevention of the spread and treatment of sick livestock. The output of this service is expected to increase the knowledge of breeders, control FMD, and the formation of an independent PMK task force in Bukek village. The methods used in service activities include; cattle breeding counseling, supplementary feeding (UMB), vitamin injection and livestock stimulation and the establishment of a FMD task force. Monitoring and evaluation are carried out to measure the success of activities. As a result of the service activities, the people of Bukek village were very enthusiastic about participating in counseling activities and understanding the pattern of cattle breeding, prevention and treatment of FMD. The provision of UMB and herbal booster FMD is given to farmers as many livestock as they have between 1-2ltr / livestock. The provision of vitamins and vaccination of livestock was carried out with relevant officials covering the ernak population in Bukek village. Vaccination data recording was submitted to the relevant service, assisted by a veterinarian from Madura University. The establishment of the PMK task force in the village was ratified by a decree of the village head for each hamlet there is representation, who has the task and obligation to record and report livestock indicated to be affected by FMD. Babinsa and Bhabinkantibmas also help in sanitary spraying of the pen using disinfectants periodically.

Has Humankind Overwhelmed Nature’s Agency?

Abstract Humankind’s relationship with nature has been evolutionary. Nature’s agency initially overpowered human agency, limiting what people could do in their quest for survival. Ever so slowly people domesticated material things, such as fire and wood, and they made tools to assist them from bones, wood, and stone that gradually became more sophisticated. These tools became the principal link between humankind and the material world, and as human communities became more complex, people produced sophisticated tools worthy of being called technologies. Ships, mills, weapons, buildings—each invention and innovation increased human agency, and nature slowly gave way before it, a process visible through landscapes. This essay focuses on North America, where between the sixteenth and twentieth centuries, human commodification of nature and the side effects of their technologies ultimately became so complex and complete that they ate away at the planetary ecosystem on which their own existence depends. Today, the Anthropocene encapsulates the idea of the age of humans, and nature’s agency seems to crumble as an independent force in the face of human actions.

Design and Gesture Optimization of a Soft-Rigid Robotic Hand for Adaptive Grasping.

Soft robotic hands are inherently safer and more compliant in robot-environment interaction than rigid manipulators, but their flexibility and versatility still need improving. In this article, a gesture adaptive soft-rigid robotic hand is proposed. The robotic hand has three pneumatic two-segment fingers. Each finger segment is driven independently for flexible gesture adjustment to match up with different object shapes. The palm is constructed by a rigid skeleton driven by a soft pneumatic spring. It provides a firm support, large workspace, and independent force control for the fingers. Geometry model of the robotic hand is established, based on which a grasping gesture optimization algorithm is adopted. The fingers achieve optimal contact with objects by performing maximal curving similarity with the object outlines. Experiment shows that the soft-rigid robotic hand provides adaptive and reliable grasping for objects of different sizes, shapes, and materials with optimized gestures.

Period, Break, Form

Abstract This essay examines the relationship between novelistic form and a historical moment shaped by new technologies in Dave Eggers's The Circle (2013) and Kim Stanley Robinson's Red Moon (2018). In both, the novel form is itself positioned as a major counterforce against the malignant powers that are attempting to form the age. Also in both, new technologies are understood not as primary or independent shaping forces but as enabling components of a larger political and economic form, a variant of capitalism. However, the crucial difference between the two novels is in how they periodize this capitalism, an act that is inseparably bound up with their generic identity. The Circle implicitly sees the growing power of the tech giants as a historical break, a departure or step-change from previous modes of capitalism, a periodizing that anticipates Shoshana Zuboff's recent, influential definition of “surveillance capitalism.” In Red Moon the new technology is less central to the plot and is capable of working for both the good guys and the bad. This relegation of technology as period marker reflects the novel's positioning of the contemporary moment—as it blurs into the near future setting—as a continuation of a longer historical arc rather than a break from it. Periodization and genre emerge as central to how these novels relate to social forms: genres are provisional and heuristic constructions that provide a way of talking about how novels negotiate, and negotiate with, history.

Epidemic spreading under mutually independent intra- and inter-host pathogen evolution

The dynamics of epidemic spreading is often reduced to the single control parameter R0 (reproduction-rate), whose value, above or below unity, determines the state of the contagion. If, however, the pathogen evolves as it spreads, R0 may change over time, potentially leading to a mutation-driven spread, in which an initially sub-pandemic pathogen undergoes a breakthrough mutation. To predict the boundaries of this pandemic phase, we introduce here a modeling framework to couple the inter-host network spreading patterns with the intra-host evolutionary dynamics. We find that even in the extreme case when these two process are driven by mutually independent selection forces, mutations can still fundamentally alter the pandemic phase-diagram. The pandemic transitions, we show, are now shaped, not just by R0, but also by the balance between the epidemic and the evolutionary timescales. If mutations are too slow, the pathogen prevalence decays prior to the appearance of a critical mutation. On the other hand, if mutations are too rapid, the pathogen evolution becomes volatile and, once again, it fails to spread. Between these two extremes, however, we identify a broad range of conditions in which an initially sub-pandemic pathogen can breakthrough to gain widespread prevalence.

Political constraints on economic diversification in the Kurdistan Region of Iraq

In many oil-rich-countries, diversification is often mentioned as a strategy for reducing the ‘curse’ of oil resources. This curse is twofold – economic and political. The economic curse is that over-dependence on oil and gas exports makes a country vulnerable to the fiscal shock of fluctuations in the price of oil and gas on the international markets which undermines the government's ability to deliver welfare programmes without running up large budget deficits by borrowing heavily to hedge against price falls. The political curse is that the oil resource invariably leads to elites monopolizing the resource for their own benefit. Advocates of economic diversification claim it could eliminate both economic and political curses. We test this claim in a case study of the Kurdistan Region of Iraq (KRI) where two political party elites control the region's oil resources, and where steps are being taken to develop the private sector to reduce the KRI's over-dependence on oil. Our finding is that while the elites approve of economic diversification as a means of reducing the region's reliance on oil, they are unwilling to allow the private sector to develop into an independent economic force which could challenge their political power. Accordingly, the political elites have taken charge of the economic diversification programme, but this has undermined its independent development because the two major political parties who share power in the Kurdistan Regional Government (KRG) have vested interests in continued imports of certain foreign products into Kurdistan and reduced imports of other foreign products. So, the parties manipulate the economic diversification policy and thereby undermine its effectiveness, in order to safeguard their own financial interests, and as a result the political curse has largely thwarted attempts to deal with the economic curse.

The social origins of democracy in Sweden: the role of agrarian politics

ABSTRACT In discussions of Scandinavian democratisation, it is commonplace to argue that long-standing farmer representation in parliament and a lack of feudalism facilitated early democratisation. The present essay questions this interpretation in the Swedish case. It centres on a re-interpretation of farmer politics at the national level from the 1866 two-chamber parliament reform to the alliance between the farmers’ party and Social Democrats in 1933. It is shown that democratisation was late and rapid; the 1866 reform was profoundly undemocratic. Swedish farmers did not organise themselves independently of nobles and landowners until the 1920s, and did not play the role of an independent pro-democratic force. The broad-based organisations of farmers in the 1920s and 1930s, with their democratic, participatory culture, were heavily influenced by the political culture of liberals and the labour movement. The implication for analyses of democratisation is that deep roots are less decisive than often supposed, and that modern political agency and organisation conversely, in contrast to influential research traditions and theories of democracy, can reverse undemocratic traditions.

The years 1918–1921: the recovery of Polish independence in the international context

The article highlights Poland’s foreign policy in 1918-1921 and emphasizes that the key role in the restoration of independent Poland was played by Józef Piłsudski, a moderate socialist leader of the independent forces of Poland, and the conservative Polish National Committee in Paris led by Roman Dmowski. At the beginning of 1919, a new Polish government was formed, which included members of both these political parties. The decision on Poland’s western borders was made at the Paris Conference. The new Bolshevik Russia and its imperialism became the most terrible threat to the newly created Polish state, as it was demonstrated in 1920 during the Polish-Bolshevik war. The idea of a friendly Ukrainian independent state in the East was not achieved, despite efforts in this direction. Another threat was associated with German revisionism. However, Poland defended its independence, and new borders of the country were established. Relations with other neighbours, Czechoslovakia and Lithuania, were strained due to border disputes. The exceptions were Romania and Latvia.

Bureaucracy as a social phenomenon

The object of scientific analysis in the article is the dual nature of the phenomenon of bureaucracy. On the one hand, it is regarded as the most rational form of organisation and management in the tradition of M. Weber. On the other hand, there are shown the main manifestations of the pathology of bureaucracy and their causes. The ambiguity of bureaucracy assessments is revealed on the ideas of S. N. Parkinson, R. Merton, A. Gouldner, A. Toffler, M. Crozier. Assessments of the nature and evolution of bureaucracy in modern society are analysed. The article reveals the positive potential of the bureaucratic form of management as well as the main negative manifestations and social consequences of bureaucracy. The implementation of the concept of "transparent" or "responsive" bureaucracy in the course of administrative reforms is shown. The article reveals the essence of the process of de-bureaucratisation as well as the content of the main system-wide and special administrative and technological measures that it includes. It is noted that system-wide measures are associated with the optimisation of the powers and activities of the bureaucracy, the prevention of its influence as an independent socio-political force, the control of civil society. Management and technological measures imply a departure from authoritarianism and the use of new approaches to management, improvement of the internal organisation and style of work of the apparatus, motivation for creative activity and people's initiatives. It is emphasised in particular that in the process of de-bureaucratisationon it is important to establish a dialogue and feedback with the population, improve the culture of management activities and communication of officials with people, create an electronic government and institutionalise the “one stop shop” service, that becomes part of this government. It is noted that sociological studies of the problems of de-bureaucratisation and improvement of the work of state authorities in Belarus allow us to say that when trying to improve the work of the apparatus, positive results are achieved faster in the field of culture of communication with the population. A positive effect is produced by the work on the creation of e-government and the institutionalisation of the "one-stop shop" service, that becomes part of this government. They simplify management procedures, optimize the forms of interaction between the authorities and the majority of the population, and are positively evaluated by people.

Analytical model of an arched elastomeric shock absorber for use in simulation modeling of systems

In this paper, a mathematical model for determining the longitudinal and transverse forces (reactions) of an arched elastomeric shock absorber when it is loaded along two axes (compression and transverse displacement of the supporting surfaces) is proposing. The reactions are presented as the sum of independent forces created by its two elastomeric walls. The webs are considered as beams that work in compression, bending and transverse shear, and can also lose stability. The model is phenomenological in nature. The structure of the model is such that in the case of pure compression of the shock absorber, the expression for the static axial reaction automatically satisfies the experimental static force characteristics of compression, which are given in the technical literature. The results of comparing the calculated data obtained by the developed model with the results of calculations in the Ansys Workbench 18.1 finite element analysis package are presented. In the region of deformations until the appearance of additional contact surfaces during buckling, a good agreement is observed. The developed analytical model of an arched elastomeric shock absorber can be used in calculations that require high speed (low computational complexity), in particular, for simulation modeling of systems in various software systems, such as Simulink.

Whisker Sensing by Force and Moment Measurements at the Whisker Base.

We address the theoretical question which forces and moments measured at the base of a whisker (tactile sensor) allow for the prediction of the location in space of the point at which a whisker makes contact with an object. We deal with the general case of three-dimensional deformations as well as with the special case of planar configurations. All deformations are treated as quasi-static, and contact is assumed to be frictionless. We show that the minimum number of independent forces or moments required is three but that conserved quantities of the governing elastic equilibrium equations prevent certain triples from giving a unique solution in the case of contact at any point along the whisker except the tip. The existence of these conserved quantities depends on the material and geometrical properties of the whisker. For whiskers that are tapered and intrinsically curved, there is no obstruction to the prediction of the contact point. We show that the choice of coordinate system (Cartesian or cylindrical) affects the number of suitable triples. Tip and multiple point contact are also briefly discussed. Our results explain recent numerical observations in the literature and offer guidance for the design of robotic tactile sensory devices.

Suppression of the wake steady asymmetry of an Ahmed body by central base bleed

The injection of fluid into the wake of a bluff body, commonly referred to as base bleed, is a well-known method of drag reduction. In the current paper we demonstrate that this method provokes a complete suppression of the steady asymmetry which otherwise dominates the natural Ahmed body wake and causes additional drag. Independent force measurements corroborate the suppression of the wake asymmetry. Different scales of base blowing reveal similar maximum drag reduction and asymmetry suppression, where the optimal blowing coefficient is found to scale with bleed-to-base area ratio as $({S}_{j}/S{)}^{1/2}$.

Predicting molecular properties of α-synuclein using force fields for intrinsically disordered proteins.

Independent force field validation is an essential practice to keep track of developments and for performing meaningful Molecular Dynamics simulations. In this work, atomistic force fields for intrinsically disordered proteins (IDP) are tested by simulating the archetypical IDP α-synuclein in solution for 2.5μs. Four combinations of protein and water force fields were tested: ff19SB/OPC, ff19SB/TIP4P-D, ff03CMAP/TIP4P-D, and a99SB-disp/TIP4P-disp, with four independent repeat simulations for each combination. We compare our simulations to the results of a 73 μs simulation using the a99SB-disp/TIP4P-disp combination, provided by D. E. Shaw Research. From the trajectories, we predict a range of experimental observations of α-synuclein and compare them to literature data. This includes protein radius of gyration and hydration, intramolecular distances, NMR chemical shifts, and 3 J-couplings. Both ff19SB/TIP4P-D and a99SB-disp/TIP4P-disp produce extended conformational ensembles of α-synuclein that agree well with experimental radius of gyration and intramolecular distances while a99SB-disp/TIP4P-disp reproduces a balanced α-synuclein secondary structure content. It was found that ff19SB/OPC and ff03CMAP/TIP4P-D produce overly compact conformational ensembles and show discrepancies in the secondary structure content compared to the experimental data.

Drag reduction of a generic transport vehicle model using a fluidic oscillator

Base blowing is performed using a sweeping jet actuator centrally located at the base of a square-back Ahmed body. Drag reduction along with a significant effect in terms of wake RSB mode suppression is reported for such fluid injection. All three scales of fluidic actuation exhibit similar wake bistability suppression characteristics. RSB mode suppression is also corroborated through independent force measurements. For all scales of actuators, the optimal blowing coefficient Cqopt is found to scale with bleed-to-base area ratio as (Sj/S)3/4, whereas the blowing coefficient corresponding to the minimum magnitude of wake asymmetry scales as Cqopt(Sj/S)5/12. The small-scale actuator also presents a more energy-efficient base blowing in terms of the amount of drag reduction achieved per energy consumed.