External Shape Research Articles

Morphological markers of ear print in Iraqi population

The outer ear is an emerging biometric that has drawn the attention of the research community for more than a decade. Empirical studies confirm, that the shape of the outer ear is unique, and it is also assumed to be stable throughout a human life time. An ear print is a two-dimensional depiction of the external ear pieces that have got into contact with a surface. In 1965, the first criminal ear print identification was made in Switzerland. The variation in shape and size of ear features makes it richer biometric tool than face. Material and method: The study performed a qualitative discrimination of the external ear shape of 143 individuals, including lobe size, lobe attachment, helix rolling, ear protrusion, and antihelix folding, by using ear photographs. Results: Six landmarks were evaluated for auricle morphometry in both sexes. There was variation in the morphological features of the external ear of the sampled subjects. The external ear features vary in both sexes. All variables were statistically significant (p ≤ 0.05). The triangle-shaped ear was prevalent in females and males had an oval shape. ear print

Epidermal piezoresistive structure with deep learning-assisted data translation

Continued research on the epidermal electronic sensor aims to develop sophisticated platforms that reproduce key multimodal responses in human skin, with the ability to sense various external stimuli, such as pressure, shear, torsion, and touch. The development of such applications utilizes algorithmic interpretations to analyze the complex stimulus shape, magnitude, and various moduli of the epidermis, requiring multiple complex equations for the attached sensor. In this experiment, we integrate silicon piezoresistors with a customized deep learning data process to facilitate in the precise evaluation and assessment of various stimuli without the need for such complexities. With the ability to surpass conventional vanilla deep regression models, the customized regression and classification model is capable of predicting the magnitude of the external force, epidermal hardness and object shape with an average mean absolute percentage error and accuracy of <15 and 96.9%, respectively. The technical ability of the deep learning-aided sensor and the consequent accurate data process provide important foundations for the future sensory electronic system.

Experimental research and analysis on the resistance characteristics of simulated ore bin in water

In order to research the variation law of the longitudinal resistance coefficient of the ore bin in the marine mining system under different length–diameter ratio, external shape, additional weight and Reynolds number, a set of experimental system for testing the resistance coefficient was designed and built independently. By analyzing the experimental results, it can be seen that under the same conditions, the resistance coefficient decreases gradually with the increase of Reynolds number and finally fluctuates around a certain value. Increasing the excitation displacement will reduce the overall resistance coefficient of the ore bin. The smaller the length-diameter ratio is, the larger the corresponding force value when the vibration acceleration of the ore bin is 0, and the larger the overall resistance coefficient is. The resistance coefficient of the cylindrical section is greater than that of the rectangular shape. In order to reduce the longitudinal vibration and the transverse towing offset, the shape of the ore bin should be cylindrical in actual design and production. At low Reynolds number, the increase of added weight will increase the resistance coefficient, while at high Reynolds number, the change of added weight will not cause the change of resistance coefficient.

Turning Up the Heat: A Multilevel Review on the Role of Corporate Governance in Climate Change

Challenges of climate change have become one of the most critical problems for society. Governance scholars show increasing interest in understanding how internal and external corporate governance actors shape firm-level environmental sustainability. Moreover, effects of corporate governance actors at multiple levels such as the individual, team, firm and supra-firm level are critical in shaping firm-level environmental sustainability. We review the literature over the period from 1992 to 2021 to identify corporate governance actors’ motivation, expertise and power required to shape firm-level environmental sustainability. Doing so, we highlight the theoretical mechanisms suggested in the extant stock of literature to examine the interfaces between levels in a multilevel synthesis. On the basis of this synthesis, we identify strengths and shortcomings in current knowledge. We present a future research agenda that identifies relevant gaps at single levels and calls for integrative research focusing on how internal and external corporate governance actors influence one another. Therefore, this study provides a conceptual basis for combining existing knowledge of corporate governance actors’ multi-level effects in shaping firm-level environmental sustainability.

Amplitude response, Melnikov's criteria, and chaos occurrence in a Duffing's system subjected to an external periodic excitation with a variable shape.

The present study considers the nonlinear dynamics of a Duffing oscillator under a symmetric potential subjected to a pulse-type excitation with a deformable shape. Our attention is focused on the effects of the external excitation shape parameter r and its period. The frequency response of the system is derived by using a semi-analytical approach. Interestingly, the frequency-response curve displays a large number of resonance peaks and anti-resonance peaks as well. Surprisingly, a resonance phenomenon termed here as shape-induced-resonance is noticed as it occurs solely due to the change in the shape parameter of the external periodic force. The system exhibits amplitude jumps and hysteresis depending on r. The critical driving magnitude for the chaos occurrence is investigated through Melnikov's method. Numerical analysis based on bifurcation diagrams and Lyapunov exponent is used to show how chaos occurs in the system. It is shown that the threshold amplitude of the excitation to observe chaotic dynamics decreases/increases for small/large values of r. In general, the theoretical estimates match with numerical simulations and electronic simulations as well.

Wpływ kształtu wzmacniających profili okiennych na wytrzymałość i sztywność skrętną okien

Leading European manufacturers of profiles intended for the production of construction joinery currently use mainly PVC profiles with various configurations of external and internal shapes, allowing the production of functional products due to their intended use, shape, possibility of building them, maintaining color and maintaining low thermal transmittance coefficients of profiles. It is important to obtain high cross-sectional strengths, especially for torsion and bending. It is related to high wind loads of structures. A profile is made of a PVC with a low Young’s modulus compared to other materials, and thus it has low stiffness and strength indicators. This leads to relatively easy deformation of the joinery profiles during assembly. To avoid this unfavorable effect, the PVC profiles are reinforced with steel sections. Currently, in the industry producing PVC profiles, open steel reinforcement profiles are almost exclusively used. This solution is very disadvantageous for reasons of stiffness. However, manufacturers use such profiles primarily for technological and price reasons. Closed profiles pose many technological problems in their production and are approx. 30% more expensive compared to the corresponding open profiles. This paper presents research on the use of closed steel stiffening sections in place of open profiles. The main advantage of stiffening closed profiles is many times greater bending and torsional stiffness compared to open profiles. The theoretical and experimental studies carried out for selected cross-sections have shown that the stresses in a closed profile are several times lower than in an identical open profile, and the torsional stiffness of a closed profile is even several dozen times higher than that of an identical open profile.

Perfect acoustic absorption of Helmholtz resonators via tapered necks

A neck tapered Helmholtz resonator possessing brilliant sound absorption in low-frequency is designed and demonstrated in this work. The strategy offers an extra geometrical degree of freedom, which will benefit perfect absorption. The structure can not only achieve perfect-absorption at 132 Hz across a deep subwavelength thickness of λ/50, but also realize adjustable perfect-absorption from 132 to 236 Hz with the same external shape. The effects of acoustic impedance and structural parameters have been comprehensively discussed for illustrating the structural advantages of sound absorption in low-frequency. Our results can pave a way for designing high-efficiency acoustic devices for sound absorption and impedance engineering.

Simultaneous measurement of external and internal surface shape and deformation based on photogrammetry and stereo-DIC

Mechanical structures with cavities such as auto rim and aero-engine casing are widely used in engineering. It is of great significance for their dynamic performance evaluation if one can measure the shape and deformation of the internal and external surfaces together. However, due to the narrow interior space and self-occlusion of complex structures, the conventional stereo-DIC unit is not applicable to impose the simultaneous measurement in the outer and inner areas. This paper is therefore concerned with a systematic solution for the issue. A reflection-assisted multi-view DIC system is configured, which consists of the stereo-DIC (SDIC) unit and the reflection-assisted stereo-DIC (RSDIC) unit. The design idea and selection essential of the RSDIC unit are stated. Subsequently, a correction model for reflection imaging is detailed. Close-range photogrammetry is specially adopted to compute the 3D global points. The extrinsic parameters of each DIC unit are estimated via the rear resection so that the individual reference frame can be transformed into a common coordinate system. Five experiments, including two tests of calibration accuracy, shape and deformation measurement accuracy, and applications in an aero-engine casing prototype, prove the precision and effectiveness of the proposed method.

Variation in human 3D trunk shape and its functional implications in hominin evolution

This study investigates the contribution of external trunk morphology and posture to running performance in an evolutionary framework. It has been proposed that the evolution from primitive to derived features of torso shape involved changes from a mediolaterally wider into a narrower, and antero-posteriorly deeper into a shallower, more lightly built external trunk configuration, possibly in relation to habitat-related changes in locomotor and running behaviour. In this context we produced experimental data to address the hypothesis that medio-laterally narrow and antero-posteriorly shallow torso morphologies favour endurance running capacities. We used 3D geometric morphometrics to relate external 3D trunk shape of trained, young male volunteers (N = 27) to variation in running velocities during different workloads determined at 45–50%, 70% and 85% of heart rate reserve (HRR) and maximum velocity. Below 85% HRR no relationship existed between torso shape and running velocity. However, at 85% HRR and, more clearly, at maximum velocity, we found highly statistically significant relations between external torso shape and running performance. Among all trained subjects those with a relatively narrow, flat torso, a small thoracic kyphosis and a more pronounced lumbar lordosis achieved significantly higher running velocities. These results support the hypothesis that external trunk morphology relates to running performance. Low thoracic kyphosis with a flatter ribcage may affect positively respiratory biomechanics, while increased lordosis affects trunk posture and may be beneficial for lower limb biomechanics related to leg return. Assuming that running workload at 45–50% HRR occurs within aerobic metabolism, our results may imply that external torso shape is unrelated to the evolution of endurance running performance.

Emulsion-based, flexible and recyclable aerogel composites for latent heat storage

Although emulsion-based, phase change material-encapsulated monolithic composites are promising for latent heat storage, their rigidity and non-recyclability imposed by the relatively dense covalent crosslinking hinder the composites from real applications. Herein, we report the fabrication of aerogel composites with flexibility and recyclability from cellulose nanocrystal-stabilized, octadecane-encapsulated Pickering emulsions solidified using physical gelation. The resulting monolithic composites exhibited controllable external shapes, and the introduction of poly(vinyl alcohol) significantly reduced the leakage of the encapsulated octadecane. The aerogel composites showed flexibility at temperature over 30 °C, and robust compressive behavior, without fracture at 70% compressive strain. The composites possessed similar heat storage (melting) temperature and heat release (crystallization) temperature to that of bulk octadecane, high heat capacity (up to 253 J.g−1) and high reusability, without obvious deterioration in heat capacity after 100 heating–cooling cycles. Moreover, the aerogel composites exhibited recyclability, simply by dissolving the composites in hot water to form emulsions and then by freeze drying to form aerogel composites. The flexibility and recyclability, together with robust compression, controllable external shapes, high heat capacity and good reusability, make the aerogel composites to be excellent candidates for latent heat storage.

(Digital Presentation) Developing Meat Alternatives with Screw-Based 3D Food Printing

Food 3D printers are next generation devices that can fabricate food products with complex internal structures and external shapes, and are expected to be used as devices for producing food products with shapes and textures that meet people's preferences, but also provide requirement of seven essential factors for a balanced diet: carbs, protein, fat, fiber, vitamins, minerals, and water [1, 2]. The food 3D printer can handle two types of food at the same time, and since it can form food in two colors, it can make food that cannot be made with a syringe nozzle. On the other hand, there are concerns about the shortage of protein supply due to the increase in population, and alternative meats that are not derived from livestock are attracting attention [3]. Currently, there are few reports of research on alternative meats using food 3D printers, and in particular, 3D modeling of alternative meat that reproduces the texture of actual meat has not been done much. In this study, we have developed a food 3D printer technology that enables the modeling of alternative meat that reproduces the texture of actual meat. We have investigated the composition of alternative meat materials suitable for 3D printing based on soy protein, and the material properties of the dough using a rheometer. In future, we will report on the movement and layering during the 3D food printing process.

Preoperative Magnetic Resonance Imaging Localization of the Normal Pituitary Gland in Nonfunctioning Pituitary Adenoma Patients Using the Radiological Sign of “Internal Carotid Artery Notch”

Asymmetric features of nonfunctioning pituitary adenoma (NFPA) are poorly understood. We investigated the asymmetry in NFPA on magnetic resonance imaging. We reviewed preoperative magnetic resonance imaging findings of patients initially treated for NFPA. The internal carotid artery (ICA) often seemed to cause an indentation in the external shape of the tumor (i.e., the ICA notch). Two cases with a normal pituitary gland located at the midline were excluded. The remaining 66 cases were examined. The side where the normal gland was located was defined as the normal pituitary side and the opposite side as the cavernous sinus side. The Knosp grade was significantly higher on the cavernous sinus side (P<0.001), and the vertical distance of the ICA was significantly greater on the cavernous sinus side (P<0.001). The ICA notch was found in 87.9% of all cases on the normal pituitary side, but in only 45.5% on the cavernous sinus side (P<0.001). In cases with a single-side ICA notch (34 of 68), the ICA notch was found in 91.2% of cases and on the cavernous sinus side in 8.8% (P<0.001). Magnetic resonance imaging of NFPA frequently shows asymmetry. The tumor does not extend laterally on the normal pituitary side but extends laterally more freely on the cavernous sinus side. The ICA notch is often found on the normal pituitary side where the position of ICA does not move. This may be useful as a preoperative sign to indicate the normal pituitary side.

Two types of installation of 3D‐printed zero tension lysimeter for soil leaching and water bucket model validation

AbstractQuantifying and analysing leaching water is essential to understand water and nutrient cycles and the vertical transport of elements through soils. Zero tension lysimeters (ZTLs) have been widely used to capture the soil solution leaching by gravity. This study designed and evaluated a 3D‐printed ZTL (ZTL3D) with specific characteristics and materials to quantitatively capture dissolved element fluxes. By 3D‐printing the ZTLs, we were able to include specific 3D structures and precise details in the design allowing installation of samplers from the surface rather than trenches, and thus avoiding the need for installation trenches to remain open. The ZTLs3D connect directly with the surface, do not depend on secondary collectors, can be installed at any depth, and samplers are easily retractable when dismantling the field set up. The material used, Nylon 12, was tested for dissolved organic carbon (DOC) release. The ZTL3D design was printed in two different external shapes while characteristics and internal design were identical. The difference in external shape was to study the effects of two contrasting types of installation: a cylindrical sampler for vertical installation (by soil coring from the surface) and a rectangular samplers for horizontal installation (from a pit or a trench wall). We installed them at different depths (2, 30 and 75 cm) in a forest soil and conducted rainfall simulation experiments. A water bucket model (WBM), created to calculate the water drainage fluxes that the ZTLs3D should collect, reproduced very well the variation in soil water content measured by soil moisture sensors installed adjacent to the ZTLs3D at 16, 30, 50 and 75 cm depth. Drainage fluxes simulated by the WBM showed that the vertical installation performed better at collecting water at all depths than the horizontal installation, but overall the ZTLs3D failed to collect the simulated amounts of drainage water. Nonetheless, the ZTLs3D did collect leachate water, enabling their chemical analysis. Combining the concentrations in the water collected by the ZTLs3D with the modelled drainage fluxes does allow estimation of DOC‐ and elemental leaching rates. This article presents the novel design of these two types of ZTLs3D because future improvements may result in better performance, and discusses their (dis)agreement with the modelled WBM fluxes.Highlights New 3D‐printed zero tension lysimeters (ZTLs) to capture element fluxes when installed vertically (cylindrical design) or horizontally (cubic design) were tested. Two external sampler shapes were created to optimise the installation process and both collected drainage water successfully. Vertical installation ZTLs worked better than horizontal types, but neither well‐reflected drainage fluxes simulated by water bucket model (WBM). Combined with WBM, both ZTL types provided a reliable method for quantifying nutrient and organic carbon leaching at different soil depths.

Nondestructive in situ monitoring of pea seeds germination using optical coherence tomography.

Seed germination and uniform plant stand in the field are the most critical crop growth stages determining the final yield. Pea ( Pisum sativum L.) seeds production is often hampered due to the seed dormancy caused by the hard seed coat. Such effect is mainly attributed to poor or uneven germination and unsynchronised seedling emergence. Understanding the time course of water intake and several critical germination indicators can reveal many features of seed germination such as rate and uniformity. This paper used optical coherence tomography (OCT), a noninvasive and cross‐sectional imaging technique, to monitor the inner structural changes throughout the germination process. A sequence of cross‐sectional OCT images of pea ( P. sativum L.) seeds, together with additional microscopic optical images, was recorded continuously and in situ for over 40 h. OCT and microscopic images revealed the changes in the internal structure and the external shape of the pea seeds during germination, respectively. It was found that the cross‐sectional OCT images helped to identify the critical indicators distinguishing the different phases of germination pea seeds. Therefore, the presented OCT approach offers a fast and nondestructive way to precisely measure the structural indicators in different germination phases.

Effect of Shape on the Temperature of an Opening Jet Plume at the Bottom of a Horizontal Member

In this study, combustion tests, in which the opening condition of a fire source was changed using a large-scale compartment and horizontal member, were conducted. The inner temperature, temperature distribution under the horizontal member, external flame shape, and neutral zone height of the compartment were measured under various opening conditions. The results were analyzed using the temperature prediction equation for the opening jet plume at the bottom of a horizontal member, proposed by the Architectural Institute of Japan (Building fire load and design fire property guideline (draft)), and a review was deemed necessary.

Sucker Shapes, Skeletons, and Bioinspiration: How Hard and Soft Tissue Morphology Generates Adhesive Performance in Waterfall Climbing Goby Fishes.

Many teleost fish, such as gobies, have fused their paired pelvic fins into an adhesive disc. Gobies can use their pelvic suckers to generate passive adhesive forces (as in engineered suction cups), and different species exhibit a range of adhesive performance, with some even able to climb waterfalls. Previous studies have documented that, in the Hawaiian Islands, species capable of climbing higher waterfalls produce the highest passive pull-off forces, and species found at higher elevation sites are likely to have more rounded suction discs than those found in the lowest stream segments. Morphology of the pelvic girdle also varies between species, with more robust skeletons in taxa with superior passive adhesion. To investigate what factors impact the passive adhesive performance of waterfall climbing gobies, we tested biomimetic suction cups designed with a range of shapes and embedded bioinspired "skeletons" based on micro-CT scans of goby pelvic girdles. We found that while the presence of an internal skeleton may provide some support against failure, the performance of suction cups may be more strongly affected by their external shape. Nonetheless, factors besides external shape and skeletal morphology may still have a stronger influence on sucker tenacity. Our results suggest that the relationship between suction disc morphology and adhesive performance may be influenced by a variety of physical factors, and live animal performance likely is further complicated by muscle activation and climbing behavior. These results have implications for the evolution of suction disc shape in adhesive fish and for improving the design of biomimetic suction cups.

Spanish Melon Landraces: Revealing Useful Diversity by Genomic, Morphological, and Metabolomic Analysis.

Spain is a secondary centre of the diversification of the melon (Cucumis melo L.), with high diversity represented in highly appreciated landraces belonging to the Flexuosus and Ibericus groups. A collection of 47 accessions of Flexuosus, Chate, Piel de Sapo, Tendral, Amarillo, Blanco, and Rochet was analysed using a genotyping-by-sequencing (GBS) approach. A total of 66,971 quality SNPs were identified. Genetic analysis differentiated Ibericus accessions and exotic materials (Ameri, Momordica, Kachri, and Agrestis), while Flexuous accessions shared ancestry between them. Within the Ibericus group, no clear genomic distinction could be identified for the different landraces evaluated, with accessions of different landraces showing high genetic similarity. The morphological characterization confirmed that the external colour and fruit shape had been used as recognition patterns for Spanish melon landraces, but variability within a landrace exists. Differences were found in the sugars and acid and volatile profiles of the materials. Flexuosus and Chate melons at the immature commercial stage accumulated malic acid and low levels of hexoses, while Ibericus melons accumulated high contents of sucrose and citric acid. Specific trends could be identified in the Ibericus landraces. Tendral accumulated low levels of sugars and citric acid and high of malic acid, maintaining higher firmness, Rochet reached higher levels of sugars, and Amarillo tended to lower malic acid contents. Interestingly, high variability was found within landraces for the acidic profile, offering possibilities to alter taste tinges. The main volatile organic compounds (VOCs) in Flexuosus and Chate were aldehydes and alcohols, with clear differences between both groups. In the Ibericus landraces, general trends for VOC accumulation could be identified, but, again, a high level of variation exists. This situation highlights the necessity to develop depuration programs to promote on-farm in situ conservation and, at the same time, offers opportunities to establish new breeding program targets and to take advantage of these sources of variation.

Determination of luminescent characteristics of organometallic complex in land and coal mining

Abstract The traditional measurement methods of luminescent materials have some problems, such as low accuracy and large amount of calculation. Therefore, a new measurement method is proposed in this article. Taking molecular capture as the core, the molecular force field is established. According to the first law of hohber_Kong’s molecules captures molecular dynamics, it extracts dynamic simulation data information and takes this as the input to establish the Markov data analysis model. The molecular dynamics data were input, and the multi-index method was used to describe the characteristics of metal complex luminescent materials. According to the external shape of the material and the tightness of molecular blocks, the dynamic observation index of the current complex can be obtained to determine the characteristics of luminescent materials. The experimental data show that the method in this article has higher accuracy, lower amount of calculation and good overall error adjustment effect. It can effectively determine the characteristics of complex luminescent materials.

Exploring the morphology of flax fibres by X-ray microtomography and the related mechanical response by numerical modelling

The external shape and internal lumen of flax fibres are investigated using X-ray microtomography (µ-CT) and finite element (FE) modelling. µ-CT reveals an intricate flax fibre and lumen morphology, with mean porosity contents between 0 and 7.2%. The FE model is based on 3D volumes obtained by X-ray µ-CT and tensile testing in the elastic domain. Numerical results demonstrate the decrease of stiffness as a combined effect of porosity and stress heterogeneity triggered by geometrical considerations. Moreover, stress concentrations induced by both surface roughness and complex lumen shape were observed, highlighting their possible implication in failure mechanisms. However, Young’s moduli are overestimated compared to experimental curves and non-linearities are not considered by the rather strong hypothesis of this model (linear elastic material: no viscosity, plasticity or damage mechanisms taken into account). Future work should include the orientation and reorientation of cellulose microfibrils upon tensile testing, as well as damage mechanisms.

Induction of 2n pollen by colchicine during microsporogenesis to produce polyploids in herbaceous peony (Paeonia lactiflora Pall.)

Polyploid breeding is an effective way to improve ornamental traits of horticultural plants. Colchicine, an anti-mitotic agent, is widely used to induce 2n gametes in horticultural plants, allowing for the production of polyploid plants through sexual hybridization. Based on an understanding of flower bud development and meiosis in pollen mother cells (PMCs) of Paeonia lactiflora cv. ‘Fen Yu Nu’, 2n pollen were obtained by injecting different concentrations of colchicine (0.1, 0.2, 0.3, 0.4 or 0.5%) into flower buds multiple times (once, twice or three times with a 24-h interval in between). External morphology, viability and possible hybridization of colchicine-induced 2n pollen were observed. Finally, P. lactiflora cv. ‘Lian Tai’ was pollinated with colchicine-induced pollen from ‘Fen Yu Nu’. Polyploids were identified among offspring by flow cytometry, chromosome counting, and molecular assessment using simple sequence repeats (SSR). Flower bud diameter of herbaceous peony was related with meiosis in PMCs. The most suitable period to induce 2n pollen was when most PMCs were in prophase I of meiosis, and when flower buds were about 11-12 mm in diameter. The highest induced incidence (%) of 2n pollen was 47.39% following treatment with 0.4% colchicine solution injected twice. The average diameter of 2n pollen was 46.01 μm, which was 1.53-fold wider than haploid pollen. SEM results indicated that 2n pollen were considerably different from haploid pollen in terms of external shape and surface decoration, and 2n pollen were mostly spherical or with an irregular shape. Induced 2n pollen could germinate in vitro and on the stigma of the female parent, but abnormalities such as pollen tube bifurcation or thickening were observed in both germinated states. The percentage of germinated 2n pollen in vitro was 12.78%. In addition, two tetraploids (2n = 4x = 20) were obtained by 2n pollen hybridization. SSR analysis indicated that tetraploids were produced by the spontaneous fusion of 2n female gametes with colchicine-induced 2n male gametes. This indicates that colchicine did not entirely inactivate 2n pollen. The production of few polyploids may be due to the abnormal germination of 2n pollen and obstacles in ploidy hybridization. Our findings fortify the foundation for Paeonia polyploid breeding.