Hybrid Element Research Articles

Study on influence of parameters of buckling behavior in soft mechanical metamaterials

Mechanical metamaterials are valued for their diverse properties and potential applications. Due to the instability and large deformability of soft mechanical metamaterials (SMMs), geometric reorganization will occur and lead to some unusual properties. It is possible to change the properties of materials by varying the parameters. Conventional SMMs contain a periodic distribution of holes with the same size and shape, which can be changed to a lesser extent. Periodic dispersion of regular through-hole patterns of various sizes or shapes into elastomers, resulting in metamaterials with more mechanical functionality and deformation scenarios. In this paper, we investigated the influence of parameters on the buckling mechanical behavior of SMMs and the buckling mechanical behavior of structures with multiple sizes and geometric shapes. The parameters studied include geometric parameters (pore shape, porosity and area ratio) and physical parameters (Poisson’s ratio and compression mode). Simulation of the buckling behavior of SMMs uses the finite element method. The finite element software ABAQUS is used, taking into account the almost incompressible characteristics of materials, the triangular quadratic plane strain hybrid element is selected (CPE6H). Numerical calculation gives the following results: Area ratio, pore shape and compression mode have obvious effects on buckling behavior, but Poisson’s ratio has little effect; the influence of parameters on the buckling critical strains varied for SMMs with various pore shapes; very different buckling behaviors will result from swapping out the pattern of holes with the same size or shape for holes with two different sizes or shapes; the expression of buckling behavior is also varied when the mix of hole shapes is modified. These findings demonstrate that the design parameters may be used to achieve the desired buckling behaviors. This is a new method that can be used to control the deformation of structures; modify the properties of the SMMs without changing stiffness; simplify the structures without significantly changing the material properties. The design path of mechanical metamaterials is increased.

Comprehensive Investigation of the Omega-Shaped Hybrid CFRP Sheet - Concrete Slab System: Experimental, Numerical and Analytical study

Fiber Reinforced Polymer (FRP) composites have been broadly applied in substitution of steel members at rehabilitation interventions thanks to their lightweight, high strength, and high corrosion resistance. Producing novel FRP-concrete hybrid structures is the next step researchers are dealing with. In this context, the present study focuses on the numerical and analytical modeling of the experimentally obtained response of hybrid FRP-concrete slabs subjected to three points bending tests. The analyzed hybrid elements consisted of an omega shape Carbon Reinforced Polymer (CFRP) sheet on which a concrete layer was cast forming a unidirectional slab member. A Glass Fiber Reinforced Polymer (GFRP) fabric was bonded to the CFRP sheet and embedded into the concrete block to provide a connection between CFRP and concrete in one of the specimens. Simulation results showed agreement with the experimental response in terms of load-displacement curve, concrete plastic strain and failure mode. After validating the model, alternative designs (width, height, and thickness of CFRP sheet and concrete block on it) were numerically tested to study the influence of the geometry of the structural system on the load-bearing capacity. Lastly, analytical formulation assuming total compatibility and based on Euler-Bernoulli theory were implemented and contrasted with the experimental response. Overall results pointed out that the optimum design would be the one with increased height of both concrete and CFRP. For this improved configuration, the load-bearing capacity was increased by up to 44%.

Morphological Performance of Vegetated and Non-Vegetated Coastal Dunes with Rocky and Geotextile Tube Cores under Storm Conditions

Coastal dune restoration projects are increasingly seen as a means of protecting the coast against storms, especially with the use of natural (plants), artificial (geotextile tube cores) and hybrid (plants and geotextile tube) elements. As geotextile tube cores have been found to negatively affect dune and beach natural morphodynamics, rocky cores are thus seen as a potential alternative. We carried out laboratory experiments to compare the performance of dunes with rocky cores, geotextile cores, and both types when coupled with planted vegetation. We investigated these elements in the context of scaled mild, moderate, and intense storm conditions. The results showed that dunes with either type of core lost more sand than dunes without cores. The addition of plants generally reduced the erosion across the various options, but most strongly for rocky cores under mild and moderate storm conditions. We also found that dunes with a high density of plants were best for intense conditions. Overall, the use of rocky dune cores, when coupled with plants, is the most suitable and sustainable alternative option in hybrid engineering projects.

Nonlinear inelastic analysis of space semi-rigid steel frames subjected to static load using plastic-zone method

A new hybrid element based on plastic-zone method is proposed for static nonlinear analysis of space semi-rigid steel frames. Four zero-length nonlinear rotational springs are added to the beam ends to model both in- and out-of-plane connection rotational behavior with appropriate semi-rigid connection models. The von Mises yield criteria are applied to govern material plasticity along the member length and throughout the cross-section using Newton–Cotes integration points. The modified generalized displacement control method is used to solve the system of nonlinear equilibrium equations. Some numerical examples are investigated to show the reliability and visual illustration of the proposed hybrid element.

An Arbitrary Polygonal Stress Hybrid Element for Structural Dynamic Response Analysis

An Arbitrary Polygonal Stress Hybrid Element for Structural Dynamic Response Analysis

Behaviour, finite element modelling and design of high strength steel homogeneous and hybrid welded I‐section beams

AbstractThe behaviour and design of homogeneous and hybrid high strength steel (HSS) beams are addressed in the present study. Six in‐plane three‐point bending tests on three different welded I‐sections were first conducted. Following the experimental investigation, a finite element (FE) modelling programme was performed, which included a validation study confirming the accuracy of the developed FE models in replicating the flexural behaviour of HSS welded I‐section beams, and a parametric study generating additional FE data on HSS welded I‐section beams over a broader range of cross‐sectional slendernesses, steel grades and loading configurations. Then, the suitability of the current Eurocode 3 cross‐section slenderness limits for HSS homogeneous and hybrid welded I‐sections in bending were evaluated. It is shown that the current Eurocode Class 2 and Class 3 slenderness limits are suitable for the classification of the outstand flange (in compression) and internal web (in bending) elements of both HSS homogeneous and hybrid welded I‐sections subjected to major axis bending, while stricter Class 1 slenderness limits are considered necessary to achieve sufficient rotation capacity for plastic design. The findings indicate that plastic design can be used for HSS structures, provided the proposed stricter Class 1 slenderness limits are employed. Further work is underway to develop advanced design approaches using second‐order inelastic analysis with strain limits for HSS welded I‐section members.

International Terrorism Using Toxic Chemicals as an Element of Hybrid Warfare

Modern terrorism is a complex system that consists of a complex of complementary processes – ideological, criminal, military, political, religious and nationalistic. Chemical terrorism is one of the elements of hybrid warfare – a new technology in the fight for the reorganization of the world at the present stage. The purpose of this article is to consider one of the elements of hybrid wars – chemical terrorism. Sources and informational basis of the research, methodology. In this work, the sources published by the Organization for the Prohibition of Chemical Weapons (OPCW) were used. The publications available through the databases PubMed, Google Scholar, eLibrary, etc. were also studied. Research method – system analysis. The probability of the use of chemical warfare agents and toxic chemicals by terrorists of various ideological orientations as part of a hybrid war strategy has been studied. The discussion of the results. Hybrid military conflicts of a non-classical nature involve the participation of international terrorist organizations in hostilities. The Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on Their Destruction (CWC) does not explicitly prohibit non-state actors from obtaining and using chemical weapons. This situation is very convenient for the states that have signed the CWC and use terrorist organizations as part of the strategy of indirect action. In such cases the information and psychological operations are aimed at the collapse and fragmentation of countries, undermining their ability to resist, discrediting their leaders, and causing a split in the ranks of the allies. This was most clearly shown in the incidents with the use of toxic chemicals in Syria. Conclusion. Working groups under the auspices of the UN and the OPCW, sent to Syria to investigate incidents with the use of sarin, proved unable to conduct objective investigations. They usually ended up on the side of the sponsors of chemical terrorist attacks, despite the evidence of falsification. This, in turn, can lead to serious military conflicts, for which the role of casus belli will be played by false news from the global media. The only mechanism that made it possible to stop such provocations in Syria was a public warning from the Russian side about the place and time of the planned false flag attack. At the same time, such a selective position of the UN and the OPCW can at any moment lead to the loss of the control over chemical weapons in certain regions of the world.

Viroid-like RNA-dependent RNA polymerase-encoding ambiviruses are abundant in complex fungi.

Ambiviruses are hybrid infectious elements encoding the hallmark gene of RNA viruses, the RNA-dependent RNA polymerase, and self-cleaving RNA ribozymes found in many viroids. Ambiviruses are thought to be pathogens of fungi, although the majority of reported genomes have been identified in metatranscriptomes. Here, we present a comprehensive screen for ambiviruses in more than 46,500 fungal transcriptomes from the Sequence Read Archive (SRA). Our data-driven virus discovery approach identified more than 2,500 ambiviral sequences across the kingdom Fungi with a striking expansion in members of the phylum Basidiomycota representing the most complex fungal organisms. Our study unveils a large diversity of unknown ambiviruses with as little as 27% protein sequence identity to known members and sheds new light on the evolution of this distinct class of infectious agents with RNA genomes. No evidence for the presence of ambiviruses in human microbiomes was obtained from a comprehensive screen of respective metatranscriptomes available in the SRA.

Questioning the Canon: Counter-Discourse and the Minority Perspective in Contemporary German Literature by Christine Meyer

Reviewed by: Questioning the Canon: Counter-Discourse and the Minority Perspective in Contemporary German Literature by Christine Meyer Bethany A. Morgan Questioning the Canon: Counter-Discourse and the Minority Perspective in Contemporary German Literature. By Christine Meyer. Translated by Dustin Lovett and Tegan Raleigh. Boston: De Gruyter, 2021. Pp. 343. Cloth $99.00. ISBN 978-3110674361. Christine Meyer’s Questioning the Canon masterfully treats the representative works of Rafik Schami, Emine Sevgi Özdamar, and Feridun Zaimoglu through a postcolonial methodology to reveal their overlooked counter-discursive aspects. In response to a field of scholarship that lags behind its Francophone and Anglophone counterparts, Meyer calls for the necessity of utilizing a postcolonial approach to Germanophone literature and its authors originating from stigmatized countries. This work questions the power relations between the center, the canon, and the margins. Utilizing Genette’s theories of “hypertext” and “hypotext,” Meyer shows which authors have written into the canon and essentially asserted themselves as “successors” to canonical authors. Meyer exposes the problems with a literary canon as a collection of texts approved for universality by cultural and academic institutions. From a position inferior to the main subject of discourse in canonical texts, the un-, under-, or misrepresented, such as women and ethnic and sexual minorities, question the ability of canonical authors to universally represent the human experience. For her methodology, Meyer convincingly demonstrates both the validity and importance of approaching German-language “migration literature” from a postcolonial perspective, which originated with “orientalism” and has developed through “mimicry” and “third space,” “subalternity,” and “writing back.” The main difference between the German-speaking canon and the Anglophone or Francophone canon lies in the aims and discourse itself. Rather than uncovering a colonialist or racist ideology in the canon, German-language authors of “migration literature” endeavor to “de-ethnicize” and “denaturalize” the canon by uncovering cosmopolitan and hybrid elements already within. The German canon does not contain the same cultural imperialism or notions of expansionism, but rather focuses on its own “cultural nation.” Moreover, Meyer points out that Germany’s immigration population does not come from colonized subjects but rather from Turkey or from nations conquered by other colonizers. Despite these differences in colonial and immigration histories, Meyer does not excuse the German canon from its share of literary protests but rather [End Page 342] shows how a postcolonial approach unveils a power struggle between the margins and center analogous to that between writers in post-colonial regions and the colonizer. In considering the conditions under which Germany’s contemporary literary canon has developed, the fraught twentieth century required the redefinition of a common patrimony and cultural foundation upon which to build its Kulturnation. Schami, Özdamar, Zaimoglu, and others have entered intertextual dialogue not only with canonical German authors but also with Shakespeare and authors of the larger Western canon. By rereading authors such as Adelbert von Chamisso, Heinrich Heine, Else Lasker-Schüler, and Johann Wolfgang von Goethe in a “minor” mode, contemporary authors of “migration literature” recontextualize these authors into a decentered space. Beginning with chapter two, Meyer introduces the counter-discursive strategies of her representative authors, including metatextuality and rewriting. Continuing through chapter six, Meyer involves us in her fruitful close readings of numerous texts to show how they write back from the East, test national traditions by diversity, write oppositionally, and utilize a bottom-up approach. Rafik Schami even writes directly to some of these authors. He adopts the position of a grandchild to Chamisso in the epistolary preface to Chamisso’s 1990 biography. To address “Harry Heine,” Schami chooses an interview in which he and Heine realize they have political persecution, exile, and marked status as a historical minority in common. Meyer reads Schami’s epistolary and interview writings as postcolonial in that he assumes a position of successor and kin rather than outsider. In Schami’s corrective (re)reading of European classics such as the fairy tales and Dracula, he rewrites the Wolf as the misunderstood outsider and the Count as misrepresented. Meyer argues that these texts and yet another text in which a fictional sultan evaluates Goethe’s corpus all point to Schami’s postcolonial tendencies to scrutinize the canon and to...

Asymmetric and Hybrid Warfare in Postmodern Times: Lesson from Hezbollah-Israeli War 2006

This paper discussed asymmetric warfare between Hezbollah as a non-state actor against Israel in the Second Hezbollah-Israeli War in 2006. This paper focused on Hezbollah's strategy as the weaker side to fight against Israel as the state with the strongest military forces in the Middle East. The battle between Hezbollah and Israel can be categorized as post-modern warfare because it has hybrid and irregular elements of warfare. That is, the war mixes the use of conventional and non-conventional methods of warfare. This paper uses the concept of hybrid warfare and Taylor’s strategy theory to explain the Hezbollah strategy against Israel. The main objective of this paper is to analyze and explain the strategies employed by Hezbollah, a non-state actor, in the Second Hezbollah-Israeli War in 2006, utilizing the concepts of asymmetric and hybrid warfare. The paper focuses on Hezbollah's use of post-modern strategies, such as guerrilla tactics, unconventional warfare methods, information warfare, and psychological tactics, to counter the Israeli Defense Force (IDF) and achieve its goals in the asymmetric conflict. This paper finds that Hezbollah uses elements of post-modern strategy by conducting guerrilla and hide-and-seek tactics, mixing the use of conventional and modern warfare equipment, the use information and media, engaging in acts of terror, and applying psychological warfare to achieve the ultimate goal the main objective) in the fight against Israel Defense Force (IDF).

Genre-Bending: A Discourse on Globalization and Culture with Implications for Music Therapy

Abstract Genre-bending is an evolving term that indicates the tendency for musical and cultural elements to interact with each other, often defying previously established genre distinctions. Evolutions of technology have expanded the way music is both created and consumed, and together with globalization, has shaped the development of a global music landscape. Hybrid elements and dynamics of music and culture have important implications for the development and exchange of musical identities outside of and within music therapy. In this article, there is a brief review of the digitalization of music technology related to consumers and curators. We highlight how digitalization and globalization have increased access through media democratization and afforded a global digital agency. This agency is explored with both the access and engagement of consumers, and the impact on curation by music creators. Those introductory elements are used for grounding the article’s main idea of genre-bending; including what it is, the ways it functions in popular music today, sociocultural and relational elements, and implications for music therapy. As part of this discourse, we highlight how the global music landscape has encouraged diverse music tastes and normalized inclusive engagement, and the subsequent importance of understanding individuals as being situated through multicultural music personhood. These shifts shape the intersubjective meaning making between therapist and client, impacting musical identities. The article concludes by delving into the ways these realities influence how music therapists hold space for curation, clients’ resources, and cultural assets through hybrid therapeutic dynamics.

Efficient simulation of the heat transfer in fused filament fabrication

Heat transfer simulations of the fused filament fabrication process are an important tool to predict bonding, residual stresses and strength of 3D printed parts. But in order to capture the significant thermal gradients that occur in the FFF printing process, a fine mesh discretization and short time steps are required, leading to extensive computational efforts. In this work a simulation framework is presented which combines several efficiency measures with the objective of reducing the computational efforts required in simulating the FFF printing process without simplifying the deposition physics or reducing the overall accuracy. Thus, the material deposition has been modeled with a hybrid element activation approach and elements are adaptively coarsened through an error-based coarsening condition. Additionally, an appropriate coarsening technique is presented for geometries with air-filled infill patterns. The accuracy of the numerical framework is experimentally validated and the efficiency of the framework is validated numerically by comparing the performance of models with and without any efficiency measures. Finally, its effectiveness is shown by simulating the printing process of a larger geometry.

Prevalence and Molecular Characterization of Methicillin-Resistant Staphylococci (MRS) and Mammaliicocci (MRM) in Dromedary Camels from Algeria: First Detection of SCCmec-mecC Hybrid in Methicillin-Resistant Mammaliicoccus lentus.

Dromedary camels are an important source of food and income in many countries. However, it has been largely overlooked that they can also transmit antibiotic-resistant bacteria. The aim of this study was to identify the Staphylococcaceae bacteria composition of the nasal flora in dromedary camels and evaluate the presence of methicillin-resistant Mammaliicoccus (MRM) and methicillin-resistant Staphylococcus (MRS) in dromedary camels in Algeria. Nasal swabs were collected from 46 camels from seven farms located in two different regions of Algeria (M'sila and Ouargla). We used non-selective media to determine the nasal flora, and antibiotic-supplemented media to isolate MRS and MRM. The staphylococcal isolates were identified using an Autoflex Biotyper Mass Spectrometer (MALDI-TOF MS). The mecA and mecC genes were detected by PCR. Methicillin-resistant strains were further analysed by long-read whole genome sequencing (WGS). Thirteen known Staphylococcus and Mammaliicoccus species were identified in the nasal flora, of which half (49.2%) were coagulase-positive staphylococci. The results showed that four out of seven farms were positive for MRS and/or MRM, with a total of 16 isolates from 13 dromedary camels. The predominant species were M. lentus, S. epidermidis, and S. aureus. Three methicillin-resistant S. aureus (MRSA) were found to be ST6 and spa type t304. Among methicillin-resistant S. epidermidis (MRSE), ST61 was the predominant ST identified. Phylogenetic analysis showed clonal relatedness among M. lentus strains, while S. epidermidis strains were not closely related. Resistance genes were detected, including mecA, mecC, ermB, tet(K), and blaZ. An SCCmec type VIII element was found in a methicillin-resistant S. hominis (MRSH) belonging to the ST1 strain. An SCCmec-mecC hybrid element was detected in M. lentus, similar to what was previously detected in M. sciuri. This study highlights that dromedary camels may be a reservoir for MRS and MRM, and that they contain a specific set of SCCmec elements. This emphasizes the need for further research in this ecological niche from a One Health perspective.

Fostering Resilience in Experiential Learning Courses

A focus on resilience in experiential education provides students in pre-professional programs opportunities to reflect upon their experiences as interns while also supporting their mental health and professional growth. Faculty must help students to identify strategies to manage stress and develop professional norms needed to thrive in a variety of work environments – whether in-person, hybrid, or remote. Capstone internship experiences offer an ideal setting to help students develop practical skills to support their personal and professional growth and identify their personal values and priorities. Field experience courses can foster student resilience by incorporating time for student journaling and reflection into all class meetings, encouraging students to identify strategies to forge a healthy work-life balance, and focusing on professional socialization by curating their online presence and mastering online collaborative tools such as Microsoft Teams that are vital elements of hybrid and remote work settings.

British Yemeni Young People’s Experience of Body Image, Home, Food, Language, and Religion

Abstract This paper provides an in-depth knowledge on the social practices of an under-researched ethnic group in the UK, the British Yemenis. Through an exploration of their lived activities in the context of the conduct of everyday life, this study uses photo-novella and semi-structured interviews in combination, to present five main themes which emerged from the study. These are body image, food, home, language, and religion. The paper shows how British Yemeni young people connect and disconnect, at different levels, times, and context, with mainstream British cultures and Yemeni subcultures, displaying elements of cultural hybridity that are unique to these individuals, yet at the same time provides some information on the Yemeni community. The study follows the daily activities of six British Yemeni young people in a longitudinal manner, exploring an understanding of how social structures and cultures have, and are continuously, impacting the young people’s conduct of everyday life. The study also contributes to the use of intersectionality and post-colonialism as analytic tools in the study of young people’s lived experiences.

Variable-Coefficient Dynamic Modeling Method for a Ball Screw Feed System in the No-Extra-Load Running State

In a ball screw feed system of high-speed/high-acceleration machine tools, large frictional and inertial forces may change the real contact state of the kinematic joints, resulting in changes in the contact and transmission stiffnesses and, hence, changes in the dynamic characteristics of the system. In this study, a variable–coefficient dynamic modeling method for a ball screw feed system is proposed, considering the influence of changes in the no-extra-load running states, such as position, speed, and acceleration. Based on Timoshenko beam elements with two nodes and four DOFs, an equivalent dynamic model of a ball screw feed system is established using the hybrid element method. The expression for the equivalent axial stiffness of individual kinematic joints is derived, considering the influence of the feed speed/acceleration under the no-extra-load running state of the system. In addition, the stiffness and mass of the screw shafts on both sides of the screw nut are calculated, considering the influence of the system’s feed position. Hence, we obtain the total stiffness and mass of the system in the no-extra-load running state and analyze the natural frequency. Finally, we conduct validation experiments on a ball screw feed system of a large gantry-type machine tool with different no-extra-load running states.

The hybridity of Indies culture in Indonesian novel translation into French

Postcolonial novels incorporating hybrid culture elements into the story present new problems for translation. The hybrid elements that appear in the source text can be maintained or removed in the translation process, depending on the strategy adopted by the translator. This research focus on the hybrid elements of an Indonesian postcolonial novel and the strategy for maintaining and eliminating hybridity in its French translation. The data source in this research is the novel Bumi Manusia (1980) by Pramoedya Ananta Toer as the source text and its translation in French. Using a qualitative approach with a comparative method, the analysis results show that most of the efforts to maintain hybridity are carried out in translating social life terms and self-names because they are related to the frequency of occurrence, the complexity of meaning, and identity. However, on the whole, the translation is less hybrid as more dehybridization occurs. Moreover, hybridity in Bumi Manusia and its French translation, Le Monde des hommes, is manifested differently. Although the translation tends to create a homologous space of one culture, it still shows linguistic and cultural hybridity.

Inheritance of spike productivity elements in F1 winter bread wheat hybrids

Inheritance of spike productivity elements in F1 winter bread wheat hybrids

Shear resistance and structural hardening resistance models for hybrid NSC-UHPC elements

Ultra-high performance concrete (UHPC) is being increasingly used as a thin overlay for deficient normal strength concrete (NSC) structural elements. Compared to reinforced NSC elements, hybrid NSC-UHPC elements have two stages' structural behaviour under high shear load before failure: monolithic action followed by a composite mechanical action. The composite mechanical action gives to hybrid elements a structural hardening capability after the occurrence of a diagonal shear crack and is not yet considered by most design standards. Two analytical models for hybrid elements under shear load are thus proposed to predict the shear resistance V R of the monolithic action and to predict the structural hardening resistance V Rsh of the composite mechanical action. The shear resistance model integrates the UHPC contribution in the estimation of the tensile strain at mid-height cross-section according to the general method of the Canadian code. The structural hardening behaviour is reproduced with a strut-and-tie system with plastic hinges, where the failure is controlled by the crushing of a concrete strut. Predictions of the proposed models are in very good agreement with 31 hybrid elements experimental results retrieved from the literature.

Modelling a pumped storage power plant on the example of the Porąbka Żar power plant

This article presents the idea and mathematical model of a pumped storage power plant. PSPS Porąbka Żar was selected as the real object for modelling. Due to the specificity of the operation of an intervention-regulatory and scheduled nature related to the coverage of power demand in the power system, the possibility of different modes of operation was taken into account in the model. Porąbka-Żar power plant is a pearl of hydro-engineering on the global stage. It is the first underground and the second largest pumped storage power plant in Poland. It is located in Międzybrodzie Bialskie, in the Silesian province. The short distance between the upper reservoir of the power station, located on Mt. Żar, and the lower reservoir of the międzybrodzkie lake, the high average head of the power station of 432 m above sea level, create great opportunities for accessibility and interference in the operation of the power station. It is equipped with four reversible Francis turbine sets, which operate simultaneously with a total capacity of 500 MW in the generator mode and 542 MW in the pumping mode. Due to its high potential and short turn-on and turn-off times of the turbine sets, it plays an important role in the national power system. The mathematical model was made in Matlab - Simulink software. An important role in the control process of the facility is played by the forecast of both power demand and contingencies. The forecasting model is equipped with elements of artificial intelligence. In addition, the article shows the possibility of supplementing an operating power plant with hybrid elements. The analysis is supported by commentary and a number of charts