External Structure Research Articles

Reflections: Putting Theory into Practice

This reflection includes my transformative educational journey as a graduate student. The journey includes early professional experience at a startup then shifts to the pivotal role of teachers in the learning process. These early experiences led to my decisions to pursue graduate studies in adult learning and human resource development. Reflecting on transformative learning experiences, I explore the often-overlooked realm of teacher support and development, delving into an integrative literature review on sociocultural factors contributing to teacher burnout and strategies for mitigation. The reflection highlights the findings from the integrative literature review including the interconnectedness of internal and external factors impacting teacher wellness, emphasizing self-efficacy and external support structures as crucial elements which were also personal and evident in my own life. I presented at the AAACE conference where these findings were also evident in the lives of attendees. I now lead a diverse team of teachers where I apply these lessons learned daily, advocating for structural supports to safeguard teacher commitment and combat burnout. The reflection underscores the intrinsic value of teachers as the “secret ingredient” in education and the ongoing quest to sustain their passion and well-being.

Wear and corrosion resistance of TiAlSi-Nix (x = 0, 5, 11, 17, 23 at%) multi-principal component alloy coating prepared by ∞ oscillating laser cladding

To improve the wear and corrosion resistance of key components and ensure the safe operation of offshore equipment, we applied an ∞ oscillating laser to prepare a TiAlSi-Ni composite coating. The effects of Ni addition on the composition, microstructure, corrosion resistance and mechanical properties of the coating were experimentally investigated. The results showed that the coating mainly presented an interdendritic - dendritic structure, and the S4 coating with 17 at% Ni had the best wear and corrosion resistance. In the reciprocating sliding friction and wear test at 10 N and 30 N, the wear rates were 0.83 and 1.66 × 10−7 mm2·N−1, respectively, which is 1/5 and 1/3 of TC4 under this load. The S4 also had the largest passivation interval and passivation film stability. The internal and external double-layer film structure ensures that it is not corroded by corrosive medium. The Ti3Al/TiNi semi-coherent interface and lattice distortion gave the Ti3Al-Ti2Ni and TiAl-TiNi eutectic interfaces a high bonding strength. Moreover, the “labyrinth effect” produced by the lamellar eutectic structure further improved the corrosion resistance. This work provides a new method for obtaining coatings with high adhesion and wear and corrosion resistance for offshore platforms.

Opportunities and barriers in digitalised labour settings in people with invisible disabilities

PurposeThe main purpose of this paper is to discuss findings from original research conducted on barriers in work-related settings for PwID and how to detach those challenges from medical diagnoses.Design/methodology/approachData on impairments, barriers and possible solutions was collected through semi-structured interviews with PwID using an interview guide based on the International Classification of Functioning, Disability and Health. The data collected was analysed using qualitative content analysis.FindingsVideocall programs, passwords, lack of social contacts or possibilities to regenerate and insufficient usability or digital skills are among the biggest barriers identified. Possible solutions include creating social opportunities, offering external structure and creating opportunities for participation.Research limitations/implicationsDue to the small number of participants the results should be seen as explorative and need to be verified further.Practical implicationsThe results made apparent, that those challenges identified can also affect people without disabilities and the offered solutions may not only help develop a more inclusive workplace but also create a healthier working environment for all kinds of people.Originality/valueThe approach appears to be a good way to separate impairments from medical diagnoses and related stigma. The impairments that were described by the interviewees do not appear disability-exclusive. It is apparent that those challenges can also affect people without disabilities and the offered solutions may not only help develop a more inclusive workplace but also create a healthier working environment for all kinds of people.

Gaussian Process-Based Learning Control of Underactuated Balance Robots with an External and Internal Convertible Modeling Structure

Abstract External and internal convertible (EIC) form-based motion control is one of the effective designs of simultaneous trajectory tracking and balance for underactuated balance robots. Under certain conditions, the EIC-based control design is shown to lead to uncontrolled robot motion. To overcome this issue, we present a Gaussian process (GP)-based data-driven learning control for underactuated balance robots with the EIC modeling structure. Two GP-based learning controllers are presented by using the EIC structure property. The partial EIC (PEIC)-based control design partitions the robotic dynamics into a fully actuated subsystem and a reduced-order underactuated system. The null-space EIC (NEIC)-based control compensates for the uncontrolled motion in a subspace, while the other closed-loop dynamics are not affected. Under the PEIC- and NEIC-based, the tracking and balance tasks are guaranteed and convergence rate and bounded errors are achieved without causing any uncontrolled motion by the original EIC-based control. We validate the results and demonstrate the GP-based learning control design using two inverted pendulum platforms.

Chiral absorption enhancement via critically coupled resonances in atomically thin photonic crystal exciton-polaritons.

Atomically thin transition metal dichalcogenides (TMDS) offer a promising route to the scaling down of optoelectronic devices to the ultimate thickness limit. But the weak light-matter interaction caused by their atomically thin nature makes them inevitably rely on external photonic structures to enhance optical absorption. Here, we report chiral absorption enhancement in atomically thin tungsten diselenide (WSe2) using chiral resonances in photonic crystal (PhC) nanostructures patterned directly in WSe2 itself. We show that the quality factors (Q factors) of the resonances grow exponentially as the PhC thickness approaches atomic limit. As such, the strong interaction of high Q factor photonic resonance with the coexisting exciton resonance in WSe2 results into self-coupled exciton-polaritons. By balancing the light coupling and absorption rates, the incident light can critically couple to chiral resonances in WSe2 PhC exciton-polaritons, leading to the theoretically limited 50% optical absorptance with over 84% circular dichroism (CD).

Development of the Pronotal Explanate Margin, a Novel Evolutionary Trait in Tortoise Beetles.

Most tortoise beetles, belonging to the subfamily Cassidinae (Coleoptera: Chrysomelidae), possess distinctive explanate margins, comprising elongations of the pronotum and elytra outer margins. These margins flatten against the ground, serving as a unique defensive mechanism against predators. To understand the developmental and evolutionary origins of explanate margins, we examined the development of the pronotal part of these structures in two tortoise beetle species: Thlaspida biramosa (Boheman) (tribe Cassidini) and Laccoptera nepalensis (Boheman) (tribe Aspidimorphini). Although final (fifth) instar larvae of both species exhibited no external prothoracic structures associated with explanate margins, pupae possessed a plate-shaped structure projecting anterolaterally on their pronotum. This plate-shaped structure was identified as the pupal primordium of the pronotal explanate margin, as the explanate margin emerged from inside the structure during eclosion. In prepupae of T. biramosa, the primordial tissue exhibited three region-specific folding and furrowing patterns, beneath larval cuticles. These epithelial structures expanded within minutes at the onset of pupation, resulting in pupal primordial formation. Thus, pronotal explanate margins originate from pronotal epithelia, with the furrowing and folding patterns of the epithelia shaping pupal and even adult pronotal explanate margins. The presence of morphologically similar pupal pronotal projections in various Cassidinae suggests that the development of pronotal explanate margins is likely common in these beetles.

Aeromagnetic geophysical data 3D inversion: Revealing internal and external structures of Morro São João Alkaline Complex, Southeast Brazil

This study investigates the internal and external structures of the Morro São João Alkaline Complex, located in Southeast Brazil, using high-resolution aeromagnetic geophysical data. The primary objective is to delineate the architecture of the underlying magma chamber system. The geophysical investigation primarily employs aeromagnetic data processing techniques, unveiling subsurface structures and shedding light on the magmatic evolution of the region. Aeromagnetic data from the Rio de Janeiro Aerogeophysics Project were processed and interpreted to identify significant magnetic anomalies and structural features. The results reveal five distinct magnetic domains correlating with various lithologies, including Monzogranite and Amphibolite Paragneiss. The observed NW-SE and NE-SW magnetic lineaments are crucial indicators of the region’s structural complexities, reflecting tectonic influences and highlighting the significance of regional geological context in deciphering magnetic anomalies. The geophysical anomaly associated with Morro São João, characterized by its rounded shape and eccentricity, aligns with the documented lithological variations. Numerical inversion techniques were employed to create a detailed three-dimensional model of the magmatic system. The main geophysical result is the 3D inversion model, which unveils a magmatic chamber approximately 4 km beneath the surface. This model reveals the subsurface architecture and conduits from the chamber, providing a dynamic perspective on the processes shaping the hill’s morphology. The integration of regional magnetic lineaments, lithological variations, and the 3D inversion model elevates our comprehension of the geophysical intricacies of the Morro São João Alkaline Complex.

Endorsed midwife prescribing in Australia: “[For] the women, more than anything”

ProblemPrescribing by Endorsed Midwives has existed in Australia for more than ten years. Significant barriers exist in the bureaucracy surrounding prescribing and state and territory legislation which further constrain midwives capacity to prescribe required medications. BackgroundCurrent evidence indicates Endorsed Midwives improve timely access to medications and can experience both enablers and barriers to prescribing. AimTo explore Endorsed Midwives’ lived experiences of medication prescribing, including which medications are being prescribed, how this affects the women in their care, midwives’ practice, and perspectives on the future of midwifery prescribing. MethodsA descriptive qualitative approach was used. Data collection occurred through semi-structured interviews (n=10) of Endorsed Midwives from varied Australian practice contexts and locations. Data analysis followed Reflexive Thematic Analysis. FindingsFour themes were developed: Medication prescription as essential healthcare; Prescribing optimises midwifery practice; External structures can both promote and inhibit the capacity to prescribe; The future of prescribing. DiscussionEndorsed Midwife prescribing has the potential to positively impact women’s maternity care and enable midwives to fulfil their scope of practice. However, limitations to prescribing need to be addressed to capitalise on these benefits. ConclusionSignificant reform of health service policy, state and territory legislation and further development of the Pharmaceutical Benefits Scheme are required to fully embrace and capitalise on the full scope of Endorsed Midwives in the Australian Healthcare system.

The quest for delightful experiences and profitable enterprises: how customer delight impacts financial performance

PurposeThe present research sought to analyze the effects of customer delight on both internal and external financial structures of publicly traded, service firms.Design/methodology/approachPrimary (i.e. survey) and secondary (i.e. financial records) data sources were gathered. A total of 685 participants responded to one questionnaire focusing on hotels and another one focused on restaurants, both of which measured levels of customer delight and satisfaction. Financial data were gathered from Center for Research in Security Prices, CRSP/COMPUSTAT.FindingsResults of MANOVA revealed that there was a significant difference in the net profit margin (NPM) based on customer delight. Canonical correlation results exposed a significant correlation between satisfaction and delight combined and the financial performance measures (net profit margin, cash flow margin, return on assets and b-beta) combined.Practical implicationsBy delighting their customers, managers will achieve higher profit margins. However, these are not likely to result in improved cash flow margin or return on assets. The effects of COVID-19 can alter yearly returns; thus, longitudinal research is needed to continue testing for the effects on delight on financial performance.Originality/valueThe relationship between delight and financial measures had not been previously determined (notwithstanding a few studies using substitute measures for financial performance). The present study uses actual data from the financial filings to empirically test their relationship to customer delight.

중거리 저상 좌석버스 표준모델을 위한 교통약자의 이용 서비스 니즈 분석

This study targets the transportation vulnerable (persons with physical disabilities using wheelchairs, persons with physical disabilities using assistive devices other than wheelchairs, the visually impaired, the hearing impaired, the seniors over 65 years of age, pregnant women, and foreigners living in Korea) residing in 17 cities and provinces across the country. We investigated the needs for services using low-floor seat buses. Therefore, in order to guarantee the right to mid-distance transportation for the transportation vulnerable, basic research was conducted to successfully develop operation technology to develop and disseminate a standard model of a low-floor seat bus that can run on automobile-only roads. The survey was largely composed of four areas: individual-related matters, movement and activity situations, low-floor bus use status, and desire to use low-floor bus services. Based on the results of the analysis, the conclusions are drawn for developing a standard model for mid-distance low-floor seat buses in the future to ensure mobility rights and active social participation for the transportation vulnerable. First, mid-distance low-floor seat bus service is absolutely necessary. Second, systematic training of drivers is urgently needed. Third, more efforts should be made to improve awareness of the transportation vulnerable. Finally, there is a need for continued interest in the internal and external environmental structure of low-floor seat buses.

Market Concentration and Firm Value

In this study, we examined the relationship between market concentration using the Herfindahl-Hirschman index and firm values among listed companies in both the markets for the period 2011–2020. We found a negative association between market concentration and firm value. This relationship was mitigated by such factors as dividend payments, auditor size, and financial reporting opacity. This study contributes to the existing literature by corroborating the influences on firm value and addressing the prevailing research paradigm suggesting that market competition is a mechanism for overseeing managerial behavior (i.e., an external corporate governance structure).

Evaluation of Ammonium Nitrate(V) Morphology and Porosity Obtained by SEM and Tomography Imaging.

This paper presents an evaluation of the morphology of fertilizer-grade and prill-grade ammonium nitrate(V). All samples were analyzed using X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and tomography techniques. The XRD results revealed that despite various provenances, all samples exhibited similar Pmmm symmetry and diffraction patterns. SEM images indicated that prill ammonium nitrate(V) showed a more complex external and internal crystal structure than fertilizer-grade counterparts. Furthermore, tomography analysis revealed that each prill ammonium nitrate(V) sample demonstrated distinct porosity characteristics, including varying pore sizes and distribution patterns. Both methods confirmed that fertilizer-grade ammonium nitrate(V) in the cross-section had a pumice structure, and porous prill ammonium nitrate(V) had a rather complex structure, with a central cavity observed only in the case of Sample 4. The appearance of a central cavity can be explained by the different conditions or manufacturing processes of porous prill ammonium nitrate(V). Moreover, the fertilizer-type ammonium nitrate(V) exhibited the lowest surface-to-volume ratio of ca. 21% compared to the porous-type ammonium nitrate(V). This, together with the lowest surface area of ca. 116 mm2, confirmed the lowest absorption capacity of the fertilizer-grade ammonium nitrate(V) disclosed by the ammonium nitrate(V) producer.

Anatomical Changes during Chestnut (Castanea mollissima BL.) Gall Development Stages Induced by the Gall Wasp Dryocosmus kuriphilus (Hymenoptera: Cynipidae).

This study delved into the larval development and the morphological and anatomical transformations that occur in the galls of chestnut trees (Castanea mollissima BL.) and are induced by the chestnut gall wasp Dryocosmus kuriphilus Yasumatsu (GWDK) across various stages: initial, growth, differentiation, maturity, and lignification. Chestnut galls in the five development stages were collected. Gall structural characteristics were observed with an anatomical stereomicroscope, and anatomical changes in galls were analyzed with staining and scanning electron microscope techniques. The chestnut gall wasp laid its eggs on young leaves and buds. Chestnut gall wasp parasitism caused plant tissues to form a gall chamber, with parenchyma, protective, and epidermal layers. The development of the gall structure caused by the infestation of the GWDK gall led to the weakening of the reactive oxygen species (ROS) elimination ability of the host. The accumulation of ROS led to cell wall peroxidation, resulting in structural damage and diminished host resistance, and the parenchyma layer exhibited significant nutrient supply and thickening. The thickness of the protective and epidermal layers varied notably across different growth stages. The oviposition of the chestnut gall wasp induced modifications in the original plant tissues, with gall formation being most favorable in young tissues, correlating with the maturity level of the host plant tissues. Variances in the internal structures of the galls primarily stemmed from nutrient supplementation, while those in the external structure were attributed to defensive characteristics. This research contributes a foundational understanding of gall development induced by the chestnut gall wasp in Chinese chestnut, offering valuable insights into the intricate interplay between insect infestation and plant physiology.

Transient characterization of the mode switching process in the reversible solid oxide cell stack

Reversible solid oxide cells (RSOCs) is a promising energy storage and conversion technology requiring frequent switching between fuel cell mode and electrolysis mode in practice. Unfortunately, it may cause a large current density undershoot that has irreversible damage to the RSOC. Therefore, understanding the transient behaviors of the RSOC is critical for its efficient and durable operation. A three-dimensional transient model of a 30-cell SOC stack with an external manifold is established. From SOFC to SOEC, the mass transfer lag and slow heat transfer cause the current density of the stack requiring 2500 s to reach a steady state. And the bottom inlet way and the external manifold structure cause differences in the current density, molar fraction and temperature variation with time between different cells. The upper cells show a slower mass transfer rate and undergo greater temperature changes. The inconsistent temperature change gradients and temperature change rates among different cells will inevitably produce changing thermal stresses and bring irreversible mechanical losses to the stack. Similar transient characteristics are observed when switching from SOEC to SOFC. However, it takes longer time (3200 s) to achieve the final steady state.

Ceramic additive manufacturing and microstructural analysis of tricalcium phosphate implants using X-ray microcomputed tomography

Additive manufacturing (AM) of ceramic bone implants from tricalcium phosphate (TCP) offers several benefits for bone regeneration and defect treatment. TCP scaffolds, e.g. featuring lattice or gyroid geometries, can effectively induce bone ingrowth and integration, showing a high potential in the treatment of large bone defects, e.g. as filler material for large bone defects. A major advantage of TCP is its osteoconductivity making it an effective choice for a broad range of orthopedic and dental applications. In addition, AM allows for the possibility to create precise, patient-specific implants with controllable mechanical properties. Those properties can be controlled by the implants' microstructure, e.g. in relation to bulk density and internal porosity. In this contribution, eleven resorbable bone implants were produced from β-tricalcium phosphate (β-TCP) in order to quantify the internal porosity in three dimensions using microcomputed tomography (μ CT). All components were manufactured using an extrusion-based process and scanned using an industrial μCT system at a voxel size of 10 μm. Two samples were physically prepared to allow a high-resolution μCT analysis at a voxel size of 1 μm. Results show that post-processed image data enables the non-destructive inspection of highly complex ceramic AM implants. Using μCT we were able to quantify internal porosity in β-TCP bone implant and quantify the geometry and distribution of wall thicknesses in the gyroid geometry. However, a detailed microstructural analysis is only possible using high-resolution μCT volume data, e.g. in relation to internal porosity. The findings emphasize that ceramic AM is able to produce complex components. However, NDT using μCT is crucial in the development of new materials and geometries. μCT provides high-resolution insights into the internal and external structure of ceramic AM components. It plays a critical role in detecting internal features, including small-scale porosity and delamination which are crucial for the integrity and functionality of medical implants. Moreover, μCT provides volumetric data that supports the design and manufacturing process at various stages, enabling an iterative approach of continuous improvement in mechanical performance and osseointegration.

Development of a vibration-damping, sound-insulating, and heat-insulating porous sphere foam system and its application in green buildings

With the development of green buildings, people pay more attention to the quality of the indoor sound environment. The air sound insulation performance of floors and exterior walls plays a key role in today's green buildings. The thermal performance of the enclosure structure's floor and exterior wall heat transfer resistance is an important factor in reducing building carbon emissions in green buildings. The aim of this paper is to study the efficiency of the acoustic and thermal insulation of a foaming system with porous carbon balls and the combination of different structural ways of construction boards and external walls. The acoustic and thermal parameters of different sound insulation and thermal insulation systems designed with porous carbon sphere foam and inserted into the floors and exterior walls are compared to highlight the optimal structure. The theoretical and experimental tests showed that to improve the sound insulation performance of the floor, a sound insulation system needs to be placed on the surface of the floor in contact with the impact object and inlaid in the vertical gap in contact with the floor and the wall. Furthermore, it has been determined that the surface of the foam particle acoustic ball with micropores has good sound absorption performance. Finally, the high-quality building thermal insulation material with low thermal conductivity in any combination with the floor slabs and the external wall structure improves the thermal insulation performance.

Nanosensor Based on the Circular Ring with External Rectangular Ring Structure

This paper presents a novel nanoscale refractive index sensor, which is produced by using a metal–insulator–metal (MIM) waveguide structure coupled with the circular ring with an external rectangular ring (CRERR) structure with the Fano resonance phenomenon. In this study, COMSOL software was used to model and simulate the structure, paired with an analysis of the output spectra to detail the effect of constructional factors on the output Fano curve as measured from a finite element method. After a series of studies, it was shown that an external rectangular ring is the linchpin of the unsymmetrical Fano resonance, while the circular ring’s radius strongly influences the transducer’s capability to achieve a maximum for 3180 nm/RIU sensitivity and a FOM of 54.8. The sensor is capable of achieving sensitivities of 0.495 nm/mgdL−1 and 0.6375 nm/mgdL−1 when detecting the concentration of the electrolyte sodium and potassium ions in human blood and is expected to play an important role in human health monitoring.

Combining ultrahigh index with exceptional nonlinearity in resonant transition metal dichalcogenide nanodisks

Second-order nonlinearity in solids gives rise to a plethora of unique physical phenomena ranging from piezoelectricity and optical rectification to optical parametric amplification, spontaneous parametric down-conversion and the generation of entangled photon pairs. Monolayer transition metal dichalcogenides, such as MoS2, exhibit one of the highest known second-order nonlinear coefficients. However, the monolayer nature of these materials prevents the fabrication of resonant objects exclusively from the material itself, necessitating the use of external structures to achieve the optical enhancement of nonlinear processes. Here we exploit the 3R phase of a molybdenum disulfide multilayer for resonant nonlinear nanophotonics. The lack of inversion symmetry—even in the bulk of the material—provides a combination of massive second-order susceptibility, extremely high and anisotropic refractive index in the near-infrared region (n > 4.5) and low absorption losses, making 3R-MoS2 highly attractive for nonlinear nanophotonics. We demonstrate this by fabricating 3R-MoS2 nanodisks of various radii, which support resonant anapole states, and observing substantial (>100-fold) enhancement of second-harmonic generation in a single resonant nanodisk compared with an unpatterned flake of the same thickness. The enhancement is maximized at the spectral overlap between the anapole state of the disk and the material resonance of the second-order susceptibility. Our approach unveils a powerful tool for enhancing the entire spectrum of optical second-order nonlinear processes in nanostructured van der Waals materials, thereby paving the way for nonlinear and quantum high-index transition metal dichalcogenide nanophotonics.

Analysis of the Design of Household First Aid Kits

In the post-epidemic era today, people are increasingly concerned about health issues and have a newer understanding of home health, which in turn is accompanied by the expansion of home healthcare needs. As an important household healthcare device, the demand for first aid kits is also gradually rising, further highlighting the need for them. Although it plays an important role as a home medical care device, deficiencies such as simple structure, lack of function, and lack of intelligence are also presented. Based on this the first aid kit will be transformed and upgraded, innovating the design of its internal and external structure, overall function, and other aspects, to create a set of diverse functions and an intelligent medical care system, so that the family health care can better integrated into people’s lives.

Correlations between amplitude rheovasographic indicators of the crus and anthropometric dimensions in volleyball players women of different somatotypes

Somatotypological features of the body can be considered as a lever of sports achievements, because they have an effect on the efficiency of the energy supply system, physical capacity, ability to adapt, and the state of the cardiovascular system. The purpose of our work is to reveal the correlations between the amplitude parameters of the crus rheovasogram and anthropometric indices in young volleyball players women of different somatotypes. A comprehensive clinical and laboratory study of the state of health and physical development of 108 volleyball players women aged 16-20 years (youth period of ontogenesis) of high sports ranks (from II adult to masters of sports) was conducted. Rheovasographic parameters of the crus in volleyball players women were determined by the method of tetrapolar rheocardiography on a certified computer diagnostic multifunctional complex. Anthropometric determination of the total dimensions of the body and chest, pelvis, limbs, and head was performed according to the recommendations of Shaparenko P. P. (2000), somatotypological – according to the Heath-Carter calculation method (1990). After somatotyping, it was established that 28 women volleyball players belonged to the mesomorphic type of constitution, 27 women athletes were assigned to the ectomorphic and ecto-mesomorphic somatotypes each, and 26 women volleyball players belonged to the medium intermediate type. The analysis of the obtained results was carried out in the license program "Statistica 5.5" using correlation analysis according to Spearman. We found that highly professional women volleyball players, who have different body types, differ in the strength and number of significant correlations between the amplitude rheovasographic parameters of the crus and anthropometric dimensions. The most numerous (18.64 % of the possible correlations, of which 6.82 % are reliable) and the strongest (3 strong with a correlation coefficient from -0.64 to -0.73) correlations between the amplitude indicators of the crus rheovasogram and parameters of the external body structure were recorded in volleyball players women of the middle intermediate somatotype. Ectomorphs had the lowest number and strength of relationships (3.18 % of possible correlations, only 1 reliable). Individual longitudinal dimensions of the body, chest girths and its diameters, transverse dimensions of the pelvis, and skinfold thickness were most often correlated with the amplitude indicators of the crus rheovasogram in women volleyball players of various constitutional types. Determining the features of the correlations is the basis for assessing the harmony of the physical development of women volleyball players and conducting further statistical modeling to determine their appropriate crus rheovasographic indicators.