Soft Elements Research Articles

Tribological Properties of MoN (Ag‐W)‐MoS2 (W) Multilayer Films in Wide Temperature Range

In nitride films, an enhanced lubrication effect has been achieved through the incorporation of a soft metal element such as Ag. However, at medium and high temperatures, the favorable tribological properties cannot be sustained for an extended period due to the rapid depletion of Ag. To address this issue, a multilayer film design with W element doping is conceived to impede Ag depletion. MoN (Ag‐W)‐MoS2 (W) multilayer films with 4 different layers are prepared, and their tribological properties are systematically characterized across temperatures ranging from 25 to 800 °C. The results indicate that the tribological properties of four different multilayer films vary considerably at different temperatures. The 8‐layer multilayer film exhibits a relatively low friction coefficient that can be maintained at wide‐range temperatures. X‐ray diffractometer patterns are obtained before and after the friction test to elucidate the lubrication phases of different layers within the multilayer films at various temperatures. Additionally, 3D profiles of wear trajectory surfaces are generated, revealing enhanced wear resistance achieved by effectively inhibiting the migration of Ag. The low friction coefficient in multilayer films can be attributed to the oxidation of MoS2 and the generation of new lubrication phases, as confirmed by Raman spectra analysis.

Kazakhstan’s Anti-China Protests: Implications for the Belt and Road Initiative in Central Asia

This article examines China’s increasing investments in Kazakhstan amid its declining soft power and growing public dissent. Focusing on Kazakhstan's strategic position within the Belt and Road Initiative, it analyzes how Chinese economic influence persists despite widespread protests and negative public opinion. Using a qualitative approach, the study synthesizes academic literature, policy analyses, news reports, and firsthand accounts to understand local views on Chinese influence. Findings show that while China’s economic power supports continued investment, the lack of soft power presents long-term risks. Without efforts to improve its image and build trust, China’s reliance on hard power may fuel anti-China sentiments, potentially leading to organized resistance and policy changes in Kazakhstan. The study emphasizes that China must incorporate soft power elements into its foreign policy to sustain influence in Kazakhstan and across Central Asia.

Materials, Structure, and Interface of Stretchable Interconnects for Wearable Bioelectronics.

Since wearable technologies for telemedicine have emerged to tackle global health concerns, the demand for well-attested wearable healthcare devices with high user comfort also arises. Skin-wearables for health monitoring require mechanical flexibility and stretchability for not only high compatibility with the skin's dynamic nature but also a robust collection of fine health signals from within. Stretchable electrical interconnects, which determine the device's overall integrity, are one of the fundamental units being understated in wearable bioelectronics. In this review, a broad class of materials and engineering methodologies recently researched and developed are presented, and their respective attributes, limitations, and opportunities in designing stretchable interconnects for wearable bioelectronics are offered. Specifically, the electrical and mechanical characteristics of various materials (metals, polymers, carbons, and their composites) are highlighted, along with their compatibility with diverse geometric configurations. Detailed insights into fabrication techniques that are compatible with soft substrates are also provided. Importantly, successful examples of establishing reliable interfacial connections between soft and rigid elements using novel interconnects are reviewed. Lastly, some perspectives and prospects of remaining research challenges and potential pathways for practical utilization of interconnects in wearables are laid out.

Turkish Airlines: facilitating Türkiye's soft power in Africa

ABSTRACT Türkiye, a re-emerging non-Western power, has intensified its relationship with Africa by strategically integrating soft power elements into its foreign policy. Unlike other actors, Türkiye assigned a special role to its national carrier, Turkish Airlines, in this endeavour. This article assesses Turkish Airlines’ role as Türkiye’s soft power actor in Africa, primarily as a facilitator and connectivity agent. It explores Türkiye’s deployment of soft power tools and instruments to expand relations with Benin, Mauritania and Somalia, countries with recent significant increases in trade with Türkiye. We argue that Turkish Airlines’ involvement as a soft power actor and facilitator of connectivity in these countries has significantly enhanced the effectiveness of various actors, contributing to achieving Türkiye's regional goals. As such, it serves to confirm and enrich soft power theory.

A Soft Exoskeleton For Hand Finger Rehabilitation Application Using Fully Elastic Pneumatic Actuators

In recent years, there has been a growing demand for wearable actuators, that can be worn on individual body parts. This demand is dynamically increasing due to the numerous potential applications such as rehabilitation and enhancing load-bearing capabilities. Exoskeletons are mechanical structures that supplement or facilitate human movements and increase the body parts natural capabilities. Despite their wide range of applications, rigid exoskeletons have several deficiencies that required further developments. Soft actuators have been developed to address these deficiencies, forming one of the main categories of easily wearable exoskeletons. The two categories - rigid and soft exoskeletons - complement each other in their structures during applications. Soft robotic elements enable precise and delicate movements while providing adequate flexibility during use and rigid units are responsible for the stable frame structure and fixation. Their combined use is applied for rehabilitation, occupational safety, and enhancing work performance purposes. The aim of this article is to physically realize a device that has a legitimate purpose in the field of human hand rehabilitation. The goal was to design, manufacture, and functionally test the elements of a device capable of assisting in the rehabilitation of fingers using completely flexible actuators.

Visco-hyperelastic material model fitting to experimental stress–strain curves using a genetic algorithm and its application to soft tissue simulants

Ballistic impacts on human thorax without penetration can produce severe injuries or even death of the carrier. Soft tissue finite element models must capture the non-linear elasticity and strain-rate dependence to accurately estimate the dynamic human mechanical response. The objective of this work is the calibration of a visco-hyperelastic model for soft tissue simulants. Material model parameters have been calculated by fitting experimental stress–strain relations obtained from the literature using genetic algorithms. Several parametric analyses have been carried out during the definition of the optimization algorithm. In this way, we were able to study different optimization strategies to improve the convergence and accuracy of the final result. Finally, the genetic algorithm has been applied to calibrate two different soft tissue simulants: ballistic gelatin and styrene–ethylene–butylene–styrene. The algorithm is able to calculate the constants for visco-hyperelastic constitutive equations with high accuracy. Regarding synthetic stress–strain curves, a short computational time has been shown when using the semi-free strategy, leading to high precision results in stress–strain curves. The algorithm developed in this work, whose code is included as supplementary material for the reader use, can be applied to calibrate visco-hyperelastic parameters from stress–strain relations under different strain rates. The semi-free relaxation time strategy has shown to obtain more accurate results and shorter convergence times than the other strategies studied. It has been also shown that the understanding of the constitutive models and the complexity of the stress–strain objective curves is crucial for the accuracy of the method.

Multimodal soft valve enables physical responsiveness for preemptive resilience of soft robots.

Resilience is crucial for the self-preservation of biological systems: Humans recover from wounds thanks to an immune system that autonomously enacts a multistage response to promote healing. Similar passive mechanisms can enable pneumatic soft robots to overcome common faults such as bursts originating from punctures or overpressurization. Recent technological advancements, ranging from fault-tolerant controllers for robot reconfigurability to self-healing materials, have paved the way for robot resilience. However, these techniques require powerful processors and large datasets or external hardware. How to extend the operational life span of damaged soft robots with minimal computational and physical resources remains unclear. In this study, we demonstrated a multimodal pneumatic soft valve capable of passive resilient reactions, triggered by faults, to prevent or isolate damage in soft robots. In its forward operation mode, the valve, requiring a single supply pressure, isolated punctured soft inflatable elements from the rest of the soft robot in as fast as 21 milliseconds. In its reverse operation mode, the valve can passively protect robots against overpressurization caused by external disturbances, avoiding plastic deformations and bursts. Furthermore, the two modes combined enabled the creation of an endogenously controlled valve capable of autonomous burst isolation. We demonstrated the passive and quick response and the possibility of monolithic integration of the soft valve in grippers and crawling robots. The approach proposed in this study provides a distributed small-footprint alternative to controller-based resilience and is expected to help soft robots achieve uninterrupted long-lasting operation.

Advocating harder soft governance for the European Green Deal. Stakeholder perspectives on the revision of the EU governance regulation

The Governance Regulation is the central coordination instrument for the European Unions' energy and climate policy. The Regulation is scheduled for revision, as it is misaligned with the updated EU framework and exhibits implementation and enforcement deficits. Our analysis reviews 136 submissions of institutional stakeholders participating in the European Commission's public consultations on the Governance Regulation and interlinked sectoral legislation. Employing a combined quantitative and qualitative text analysis, we examine the most salient issues for different stakeholder groups. We focus on stakeholder demands that address the implementation and enforcement deficits by introducing harder soft governance elements. While we find broad support among stakeholder groups for a revision and the improvement of implementation, Public Authorities exhibit reluctance for further binding elements, with the exception of demands for more precise enforcement mechanisms. While the inclusion of harder soft governance is only of subsidiary interest for non-public stakeholders demands for stronger obligations (e.g. binding national targets), justifications and public participation can be identified. The analysis finally discusses how the further introduction of harder soft governance elements has the potential to advance the EU's energy and climate framework.

Assessment of Amphibola crenata as a bioindicator of estuarine trace element pollution using biochemical and physiological endpoints

To assess its utility as a bioindicator of estuarine contamination, Amphibola crenata, a pulmonate mud snail, was collected from 17 estuaries in New Zealand. Whole-body soft tissue trace element concentrations were measured via quadrupole inductively coupled plasma mass spectrophotometer (Q-ICP-MS) and were found to be significantly positively correlated with sediment trace element profiles for arsenic, copper and lead. Snails from polluted estuaries generally displayed higher ammonia excretion rates, elevated whole-body soft tissue catalase activity and lipid peroxidation compared to snails from reference sites. Across all sites haemolymph glucose was positively correlated with the tissue burdens of arsenic, copper, nickel and zinc, while haemolymph protein was negatively correlated with arsenic, cadmium and zinc soft tissue concentrations, indicative of altered energy metabolism associated with trace element contamination. Overall, sites were distinguishable by application of the array of measures employed. Our findings suggest that gastropods have significant value as bioindicators of estuarine health.

FlexiStiff: A Variable Tensile Stiffness Element for Modulating the Behavior of Tensegrity Structures

Soft and tensegrity structures are two configurations that have appeared as robots continue to draw inspiration from nature and diversify beyond rigid machines toward compliant systems. One artificial manifestation of a biological attribute that is an active research topic is the body's capacity to calibrate its stiffness for adapting its behavior to a given task. This study brings together these designs spaces and presents a soft tensile element named FlexiStiff for tensegrity structures to enable transitioning between flexible and stiff states for variable load‐bearing capability and compliance. The device's tensile stiffness constant can be increased by 4400% with a change in pressure. It can provide a high blocking force of 535.5 N and can endure elongation up to 184%. It is assembled using four commercially available materials and a two‐step fabrication method consisting of 3D printing and elastomer curing. As opposed to classical tensegrities for which shape change is inexpensive in terms of energy, this work betokens a new stage in their design wherein the arrangement can radically alter the magnitude of its demand for external energy for shape morphing, a crucial characteristic for operation in partially mapped environments that present diverse terrains and disturbances of varying intensities prompting adaptability.

Enhancement of work place comfort through the use of soft landscape

The work environment has been shown to have a great influence on employees’ physical and mental state, as such employers try as much as possible to provide a comfortable working environment. However, recent studies have shown that the work environment is no longer as comfortable as it used to be due to heat gain from the increasing use of hard landscape features and neglect of soft landscape features in the work environment. This has resulted in stress causing both mild and severe health conditions for employees. Thus, this study aims to analyze the use of soft landscape in enhancing users' comfort with the view of reducing stress and health-related issues in the work environment. The paper adopted a mixed method using observation checklists, structured interviews, questionnaires, and case studies. A total of eighteen office complexes were selected to describe the existing situation as related to most office complexes and to also gain insight into the subject matter as already applied to life situations. Structured interviews and questionnaires were also conducted with occupants of the buildings and professionals to hear their perceptions and expectations of their work environment. Results showed that 20 percent of the offices give proper consideration to the use of soft landscapes in the work environment, and 40 percent give inconsiderable attention to soft landscapes while making use of them in small quantities solely for improving the aesthetical value of the building. In comparison, the remaining 40 percent do not consider landscape use as a means of improving comfort in the work environment. Findings also revealed that 80 percent of office buildings give major consideration to parking space using hard landscapes without a proper blend of soft landscapes after building design which hurts occupant comfort. The research concluded that the incorporation of soft landscape elements both within the building using recesses and protrusions and on the building walls through the use of exoskeleton and climbers while incorporating trees, shrubs, flowers, hedges and water around the building can have these required effects on employee’s comfort.

The Integration of Soft Skills in Language Learning Classroom: The Perspective of Thai ELT Teachers at A University of Technology

Upon graduating, students are expected to have acquired soft skills to meet potential employers’ expectations. Since employers today are competing for qualified graduates possessing relevant training and workplace competencies, ELT teachers should guide their learners towards obtaining both a comprehensive understanding of theoretical concepts and a range of interpersonal abilities. This study examined whether Thai teachers incorporate these soft skills in the classroom, which soft skill elements are prioritized and taught, and how the teachers implemented these elements in their EFL classrooms. Twenty ELT teachers from Rajamangala University of Technology in Thailand participated in an online survey and semi-structured interviews. Data was collected using a 4-point Likert-scale questionnaire, which revealed that the teachers reported that they integrated soft skills into the classroom, primarily in the domains of learning skills, literacy skills, and life skills. The three soft skills reported to be most utilized were communication skills, technology literacy, and collaboration and teamwork, which are all essential for improving English language proficiency. The findings suggest that ELT teachers identify and facilitate the acquisition of weaker supplementary skills, such as leadership, to equip students with the necessary skills to succeed.

Soft Chemiresistive Sensing Shields Soft Robotic Actuators from Mechanical Degradation due to Critical Solvent Exposure

Thermoplastic elastomers (TPEs) are popular for fabricating soft actuators thanks to their compatibility with thermoplastic processing methods, like material extrusion additive manufacturing. However, these TPEs are susceptible to nonpolar solvents, and upon exposure, the mechanical properties can diminish significantly. Herein, soft chemiresistive sensing elements based on thermoplastic elastomers and carbon black (CB) are developed for detecting the presence of nonpolar solvents. A low CB concentration (20% w/w) leads to a faster response for detecting the presence of nonpolar solvents. A threshold value of the electrical current is defined by tensile testing, based on exposure time that does not diminish the mechanical properties. Exposure to solvent vapor above 150 s decreases the elongation at fracture significantly (450%). To achieve nociceptive behavior for a sensorized soft actuator and shield the actuator from structural damage, this threshold value is used for programming a closed‐loop control motion system. When the threshold value is reached, the actuator withdraws from the solvent surface autonomously. However, this threshold decreases with parameters like the solvent temperature and sensor distance from the solvent surface. Overall, adding soft chemiresistive elements into elastomer‐based soft robots extends their lifetime, by preventing damage in harsh chemical atmospheres.

China’s Africa Policy during the Xi Jinping Era (2012-2022)

This study examines China's Africa policy during the Xi Jinping era, in the context of political, economic, security, and socio-cultural aspects. Africa is one of the regions of strategic importance, especially in terms of meeting the energy and raw material demands of global and regional actors, despite the significant lack of accumulated capital. In this regard, China has notably intensified its relations with African countries, particularly since the 1990s. China's approach to Africa began with collaborations based on economic interests, progressed to consolidating political relations through soft power elements, and the establishment of reliable relations in this process has also paved the way for China to become a security actor in the region. In the study, these aspects are considered as turning points and are examined through the process tracing method. Consequently, the main objective of this study is to analyze China's Africa policy during the Xi Jinping era specifically using the process tracing method.

Planar soft space robotic manipulators: Dynamic modeling and control

Space robots have proven their ability to accomplish many space missions impossible or dangerous for the human. However, the conventional space robots suffer from the low adaptability, heavy structures, and the low safety. In this regard, the bio-inspired soft robots, composed of the soft material, have been emerged to overcome these shortcomings and to expand the space missions’ diversity. The potential of soft robots for space applications has recently been investigated in the literature. Although the dynamic modeling and control of soft robotic arms are complicated due to their infinite degrees of freedom, soft manipulators are anticipated to provide the adaptive capture of targets, confined space operations, and the long-distance handling of space facilities. In this regard, a general novel dynamic modeling algorithm is presented here for soft space robotic manipulators (SSRM) in a specified orientation based on the generalized Jacobian method. The proposed algorithm could be employed for different numbers of soft manipulator constant-curvature elements and avoids numerical singularities using the Taylor expansion as well. In addition, the generalized Jacobian matrix is defined to compute the velocity of any arbitrary point on the soft manipulator for contact dynamics objectives. Accuracy of the proposed dynamic model has been verified via comparison to the simulation results of the existing fixed-base soft manipulators. Moreover, performance of the proposed model has been more investigated through two numerical simulation case studies. The first case verifies that the dynamic responses of the floating SSRM follows the physical principles. While the second one addresses the configuration tracking problem of the floating SSRM exposing a computed torque control scheme. The obtained results indicate the effectiveness of the presented dynamic modeling algorithm and the proposed control scheme.

Mitigation of Railway-Induced Ground Vibration by Soft Support Elements and a Higher Bending Stiffness of the Track

The mitigation of train-induced ground vibrations by track solutions is investigated by calculations and measurements. The calculation by a wavenumber domain method includes the correct vehicle–track interaction and the correct track–soil interaction. Some theoretical results for elastic elements and an increased bending stiffness of the track are presented where the force transfer of the track and the vehicle–track interaction are calculated for the high-frequency dynamic mitigation, and the force distribution along the track is calculated for the low-frequency mitigation which is due to the smoother impulses from the passing static loads. Measurement results for the ground vibration near isolated and un-isolated tracks are given for several under-sleeper pads, for under-ballast mats, and for several under-ballast plates and ballast troughs. The elastic elements yield a resonance frequency of the vehicle–track–soil system and a high-frequency reduction of the dynamic axle loads which depends mainly on the softness of the pads or mats and which can be improved by a higher sleeper mass. In addition, all troughs and most of the soft elements show a low-frequency reduction which is attributed to the scattered impulses of the static axle loads. Besides this main contribution of the article, the problem of a soft reference section on a different soil is discussed and recommendations for better ground vibration measurements of mitigation effects are given.

Hookahs and smoldering hookah coals as an object of forensic fire and technical expertise

The subject of the study is to establish the involvement of smoldering hookah coals in the occurrence of a fire during the production of a forensic fire-technical examination. Currently, there is no universal concretized algorithm for determining the involvement of tobacco smoking devices and hookah coals in the occurrence of a fire for all possible cases of fire. The authors have attempted to combine well-known information about the detection of signs of exposure to combustible materials from a relatively low-power ignition source with the results of experiments and studies of smoldering hookah coals. Two types of hookah coals were selected as objects of research: cubic natural charcoal for hookah, fast-burning cylindrical coal. Cotton fabric, cotton wool, paper, wood (pine), synthetic carpet with fine pile, synthetic carpet with large pile, soft decorative elements with synthetic filling and a pillowcase made of furniture fabric, PVC floor materials (linoleum, PVC tiles), floor panels, lined with polymer films (laminate). In conducting this study, a systematic approach was applied to the analysis of the situation of a fire-related incident, as well as general scientific empirical and theoretical research methods (observation, comparison, description, measurement, analysis and synthesis, etc.) The results of empirical studies confirm the hypothesis of the formation of deep charring zones in places of contact of hookah charcoal with combustible materials (wood, laminated floor coverings). Based on the results of experimental studies, a step-by-step algorithm for constructing versions about the occurrence of a fire from smoldering hookah charcoal is formulated, including focusing the attention of an expert (a person conducting an inspection of the scene of an incident related to a fire) on the need to take into account factors such as the time of the fire and the induction period of ignition, the presence of conditions for heat accumulation, the presence of air exchange, the presence of an air inflow into the smoldering zone, the presence of signs of the dynamics of fire propagation, characteristic of low-power ignition sources. It is noted that the probability of burning from smoldering hookah coal increases in cases where conditions are created for the smoldering process to proceed with minimal heat loss, the possibility of heat accumulation and the presence of an oxidizer (oxygen in the air) in sufficient quantities.

Anticorrosion and Antimicrobial Tannic Acid-Functionalized Ti-Metallic Glass Ribbons for Dental Abutment.

In this study, a recently reported Ti-based metallic glass (MG), without any toxic element, but with a significant amount of metalloid (Si-Ge-B, 18 atom %) and minor soft element (Sn, 2 atom %), was produced in ribbon form using conventional single-roller melt-spinning. The produced Ti60Zr20Si8Ge7B3Sn2 ribbons were investigated by differential scanning calorimetry and X-ray diffraction to confirm their amorphous structure, and their corrosion properties were further investigated by open-circuit potential and cyclic polarization tests. The ribbon's surface was functionalized by tannic acid, a natural plant-based polyphenol, to enhance its performance in terms of corrosion prevention and antimicrobial efficacy. These properties can potentially be exploited in the premucosal parts of dental implants (abutments). The Folin and Ciocalteu test was used for the quantification of tannic acid (TA) grafted on the ribbon surface and of its redox activity. Fluorescent microscopy and ζ-potential measurements were used to confirm the presence of TA on the surfaces of the ribbons. The cytocompatibility evaluation (indirect and direct) of TA-functionalized Ti60Zr20Si8Ge7B3Sn2 MG ribbons toward primary human gingival fibroblast demonstrated that no significant differences in cell viability were detected between the functionalized and as-produced (control) MG ribbons. Finally, the antibacterial investigation of TA-functionalized samples against Staphylococcus aureus demonstrated the specimens' antimicrobial properties, shown by scanning electron microscopy images after 24 h, presenting a few single colonies remaining on their surfaces. The thickness of bacterial aggregations (biofilm-like) that were formed on the surface of the as-produced samples reduced from 3.5 to 1.5 μm.

Indonesia's Defense Diplomacy Strategy in Facing China's Gray Zone in the South Chine Sea

Purpose: This study aims to identify an effective strategy for Indonesia to counter China's gray zone tactics in the South China Sea. Theoretical Reference: Employing a quantitative method with a descriptive approach rooted in the positivist philosophy, this research follows the principles outlined by Sugiyono (2011). This method is chosen for investigating specific populations or samples, with a focus on quantitative/statistical data analysis to test predetermined hypotheses. Method: The research employs multiple regression analysis to assess the significance of Soft Power Diplomacy and Smart Power Diplomacy strategies as essential national resources for persuading China to undertake desired actions in addressing the challenges posed by China's Gray Zone in the South China Sea. Smart power, as defined by Jr J.N. (2007), involves integrating soft and hard power for a comprehensive strategy. According to R. Wilson (2008), smart power effectiveness lies in combining a robust military force with investments in alliances, partnerships, and cooperation. Result and Conclusion: The findings indicate that both Soft Power Diplomacy and Smart Power Diplomacy are influential tools and strategies within Indonesia's foreign policy context to effectively navigate and counteract China's Gray Zone activities in the South China Sea. Implications of Research: The identified strategies hold significant implications for shaping Indonesia's defense diplomacy against China's gray zone tactics, emphasizing the importance of integrating soft and hard power elements for a more comprehensive and efficient approach. Originality/Value: This research contributes to the field by highlighting the relevance and effectiveness of Soft Power Diplomacy and Smart Power Diplomacy as key components in Indonesia's defense diplomacy strategy, providing a nuanced understanding of countering China's Gray Zone activities in the South China Sea.

Soft algebraic structures embedded with soft members and soft elements: an abstract approach

Soft algebraic structures embedded with soft members and soft elements: an abstract approach