Kind Of Deformation Research Articles

A Novel Scaffold-Reinforced Actuator With Tunable Attitude Ability for Grasping

Owing to high compliance, adaptiveness, and easy controllability, soft actuators are widely adopted in soft grippers to grasp irregularly shaped or fragile objects. The specific motions can be preprogrammed into the flexible and constrained structures of the actuator, which provides an inexpensive and convenient method for desired motions. However, most preprogrammed structures cannot change the constraints on the actuator to achieve different kinds of deformations, which limits the motion diversities of actuators. This article proposes a scaffold reinforcement mechanism, where rotatable scaffolds distribute on the surface of the soft structure. The orientation adjustments of the scaffolds can change the deformation constraint of the actuator, which results in different kinds of motions. Based on the scaffold reinforcement mechanism, a scaffold-reinforced actuator is proposed, which can achieve bending motion and complex helical motion in the 3-D space by properly adjusting the orientation of the scaffolds. In addition, both the kinematic and mechanical models are proposed to forecast the behavior of the actuator when driven by cable displacement or tension force. Experimental results verify the validity of the theoretical model, and the actuator can achieve an independent control of bending and helical motion, which can be adopted in applications where both high dexterity and flexibility are required.

Automatic Parts Correspondence Determination for Transforming Assemblies via Local and Global Geometry Processing

Transforming assemblies are products that alter their shapes by re-assembling their parts. This idea is applied to a wide range of objects from folding gadgets as outdoor gear aimed at saving space, to robotic characters fighting in Hollywood films which drastically change their appearance. While the former type falls into a folding or packing problems, the latter requires a different viewpoint to be solved since the destination shape is not necessarily aiming at minimizing the occupation space. As a possible solution, this kind of deformation can be decomposed into segmentation of the shape to parts and parts matching. Segmentation is a general problem in shape modeling and numerous algorithms have been proposed for this. On the other hand, matching simultaneously multiple parts (many-to-many matching) has hardly been explored. This study develops a many-to-many matching algorithm for surface meshes of parts from two distinct destination shapes of a single transforming assembly. The proposed algorithm consists of a local geometry analysis and a global optimization of parts combination based on such analysis. For the local geometry analysis, the surface geometric feature is described by a local shape descriptor. Some vertices are detected as feature points by intrinsic shape signature (ISS) and the geometry at the feature points is expressed by the signature of histogram of orientation (SHOT). For all the combination of pairs from each destination shape, the number of feature points with similar descriptor values is counted. In the global optimization, the final matching is determined by the maximum weight matching on a complete bipartite graph whose nodes are the parts, and edges are weighted by the number of the feature points with similar descriptors. We present successful results for several examples to empirically show the effectiveness of the proposed algorithm.

Design and Development of Improved Coyote Optimization-based Adaptive Equalization Technique for ECG Signal Transmission

Biological signals such as an electrocardiogram (ECG) are broadcast directly through wireless devices and mobile networks during patients' real-time activities and over limitless distances. However, the transmission of signals through a limited band channel or over multi-propagation suffers from limitations such as inter-symbol interference (ISI). In channel output, the adjacent symbols smudge and integrate with each other by degenerating during error analysis. Equalization filters are used to improve such kinds of deformation. A new adaptive equalization approach is proposed in this paper to extract real broadcasted signals from Gaussian noise-distorted ECG signals using the enhanced meta-heuristic algorithm. The weight optimization strategy of the "adaptive equalization technique" is implemented using oppositional searched coyote optimization algorithm (OS-COA). The main purpose of adapting the improved meta-heuristic-based adaptive equalization technique is to decrease error in the section of receivers, thus ensuring the received ECG signal is error-free. The obtained outcomes are examined to evaluate the performance of error metrics like "mean square error (MSE), and convergence rate" of the introduced model and for comparison with other existing equalization approaches. According to the experimental evaluation, the recommended adaptive linear equalization technique has better extraction performance than other blind and nonlinear equalization approaches.

Striatal Hand Deformities in Parkinson's Disease: Hand Surgical Perspectives.

The knowledge about striatal hand deformities (SHD) in Parkinson's disease (PD), has recently increased but need more attention due to their early impact on dexterity. The focus of clinical studies has been on the staging of SHD severity and neurological features. However, a hand surgical perspective has not been considered. Our purpose was to examine SHD in patients with PD using hand surgical assessment methods and the recommended staging of SHD. In this observational study, a specialist in neurological physiotherapy examined 100 consecutive PD patients and identified 35 with suspected SHD, who were then examined by two hand surgeons. Their hands were clinically evaluated for severity of SHD, according to a previous proposed staging, focusing on metacarpophalangeal (MCP) joint flexion, presence of intrinsic and extrinsic tightness, as well as other hand deformities. Three kinds of deformities were identified among 35 included patients: surgical diagnoses unrelated to PD (n=5), SHD (n=23), and PD related hand deformities with increased extrinsic tightness (n=10); three of these 10 patients had also contralateral SHD, thus are included in SHD group. In addition to previously described MCP joint flexion, swan neck deformity and z-thumb deformity, we found in most hands finger "clefting," abduction of the little finger and/or an increased intrinsic tightness, indicating pathology of intrinsic muscles of the hand involved in SHD. SHD diagnosed with a modified staging method, including features of intrinsic and extrinsic hand deformities, should be considered in PD to implement early and more accurate treatment.

Surgical treatment of severe complex thoracic deformity with Wenlin procedure and Wung procedure

The complex thoracic deformity has both protrusion and depression on the chest wall, and its appearance is complex. It is difficult to complete the correction by ordinary surgical methods. In the early years, this kind of deformity needed to be treated by open surgery. After entering the era of minimally invasive surgery, its operation is also gradually minimally invasive, and it can be completed through the combination of different operations. Mild complex deformities can be treated by sandwich surgery. However, for severe complex deformities, the most ideal combination should be Wenlin procedure combined with Wung procedure. This paper introduces the treatment of a case of severe complex thoracic deformity with this ideal combined operation.

Enhancement mechanism of fracture-resistance of CrMnFeCoNi high-entropy alloys: A molecular dynamics study

It has been found that amorphization in high-entropy alloys (HEAs) can happen under the condition of severe plastic deformation. Therefore, understanding the interaction of amorphization with other kinds of deformations has become an important issue for the design of the mechanical properties of HEAs. However, the underlying mechanism of such interaction in HEAs remains unclear. Here we found in our molecular dynamics simulations that the synergistic effects of amorphization and dislocations could significantly improve the fracture-resistance of CrMnFeCoNi HEAs. It shows that amorphous structures and dislocations appeared simultaneously in HEAs, where the amorphous structures are confined by the surrounding dislocations. Once a crack propagates, some dislocation zones would become amorphous, and the local stress concentration could be relaxed during such kind of transformation instead of crack propagation, resulting in the improvement of the fracture-resistance of CrMnFeCoNi HEAs. In contrast, in nickel single crystals, only dislocations appear and fracture is more likely to occur when dislocations are emitted. It was also found that the length of cracks could affect the evolution of the microstructures in the HEAs. These findings provide new insights into the synergistic effects of the interaction between amorphization and dislocations on the enhancement of the fracture-resistance of the HEAs, which may help to improve the mechanical properties of high-performance HEAs.

Self-winding liquid crystal elastomer fiber actuators with high degree of freedom and tunable actuation

Liquid-crystal-elastomer (LCE) fiber actuators capable of reversible, large-scale, programmable deformation in response to external stimuli have great potential in many applications, including artificial muscles, robotics, and wearable devices. Despite their exciting prospects, limitations -such as few modes of shape transformation in a single actuator due to limited degree of freedom (DOF), difficulty to concurrently gain large length change and powerful stress, lack of scalable manufacturing method - seriously restrict their engineering applicability. Here we present bioinspired self-winding LCE fiber actuators that possess diverse controllable shape transformations (bending, twisting, coiling, and shortening), a combination of high contraction ratio (1750%) and high stress (∼3.4 MPa), long term photomechanical robustness (over 1000 photodeformation cycles without obvious fatigue), and readily, scalable manufacture. Our fiber actuators can simultaneously conduct two or three kinds of deformation and thus enables complex morphing behaviors to manipulate objects (grabbing, dragging, lifting, and winding), and even drive gear set. We envision that these self-winding fiber actuators combined with high DOF, tunable actuation, photomechanical robustness, and mass production could be developed as high-performance artificial muscles for broad engineering applications.

The potential and limits of Thin-Plate Spline retrodeformation on asymmetrical objects:simulation of taphonomic deformations andapplication on a fossil sample of limb long bones

In this study, we suggest a method adapted to the retrodeformation of asymmetrical objects – such as limb bones – by quantitatively estimating the effectiveness of the Thin-Plate Splines (TPS) interpolation function as a retrodeformation tool. To do so, taphonomic deformations were first simulated on a single horse femur. The original bone was then used as a reference in order to drive the retrodeformation using anatomical landmarks. This approach, based on a single bone, enabled us to evaluate the performance of the retrodeformation procedure. Then, the same approach was performed on a sample of rhino femora but using a different specimen (from the same species) as the reference in order to account for morphological variation. We also added sliding semi-landmarks on anatomical curves. Finally, retrodeformation was applied on a sample of sauropodomorph dinosaur femora by building a mean shape based on several well-preserved fossil specimens. Results show that entirely flattened and stretched bones are more efficiently retrodeformed than bent and twisted bones. Introduction of morphological variation increased the efficiency of retrodeformation for bent and locally stretched bones. The application to the sample of fossils produced similar results but also highlighted the difficulty of retrodeforming bones with a combination of different deformations. TPS interpolation is an efficient tool of retrodeformation for asymmetrical objects, especially for bones with only one affine deformation such as flattening or stretching. Finding a threshold of landmark number to use for this process would be the next step because it would allow us to ensure the quality of retrodeformation while keeping available a reasonable number of landmarks in order to perform shape analysis on retrodeformed bones. Twisted and bent fossils are frequently discovered and we suggest that these kinds of deformations should be studied with caution, especially when combined with other types of taphonomic distortions.

Damage behaviour of an Al2O3 particle-reinforced 6061 alloy induced by monotonic and cyclic deformation

Abstract The influence of damage and its correlation with the failure behaviour is discussed in the light of microstuctural aspects. The failure induced by microstructural mechanisms of the Al2O3-particle reinforced aluminium alloy 6061 under uniaxial tensile as well as under cyclic loading was investigated. The damage behaviour as a function of the strain ε can be correlated with stiffness E(ε). Under cyclic loading conditions the damage increases with the number of cycles and can be correlated with the strain amplitude εa. Furthermore, the damage is associated with crack formation and propagation and the damage evolution depends sensitively on the kind of deformation. The crack formation was detected by metallographic investigations and calculated by numerical methods (FEM), taking the size and shape of particles into account. Generally, damage under mechanical loading is initiated by broken particles and agglomerations of particles. In case of the particulate-reinforced specimens the evolution of damage is quite different for monotonic and cyclic loading conditions but, nevertheless, in both cases the damage parameter is given by inhomogeneities characteristic for the MMC which act as seeds for crack initiation.

Numerical and physical modeling of wind loads on long-span shell structures

Introduction. Wind load has a significant impact on buildings and structures. It triggers the evolution of the stress-strain state that causes various kinds of deformations. Requirements, applicable to the serviceability limit state, are important for the construction of long-span structures. In some cases, the analysis of the distribution of wind effects over the surface of a construction facility may be a challenging task. The purpose of the study is to identify the pattern of the wind load distribution over the shell of a long-span structure using physical and numerical methods, compare and analyze the obtained results.
 Materials and methods. In the course of the study, a model of the shell structure was tested in the wind tunnel in the course of the physical testing. The model was made of polymer materials using the 3D printing technology. In addition, the article addresses the procedure for conducting full-scale tests in a wind tunnel. Numerical modeling was performed using various software and numerical software packages, such as Ansys CFX, SOLIDWORKS.
 Results. The article presents the results of physical tests conducted in a wind tunnel, demonstrates the tables that have the values of aerodynamic coefficients and wind pressures, on the basis of which colour pressure isofields are made. Also, the article presents the results of iterative calculations of numerical models made using various software and numerical software packages. In addition, wind flow distributions were analyzed, since the object of the study has such a characteristic feature as an open-air shell, which allows the air flow to reach the structure from below.
 Conclusions. The authors analyzed the data obtained as a result of the research; the convergence between the results of physical tests and numerical modeling in Ansys CFX was identified, a great discrepancy between numerical and physical studies was identified as a result of the application of other software packages. When designing buildings and structures, having intricate geometric shape, both physical and numerical modeling should be conducted.

Algorithm based on normal coordinate vectors with 16 segments for the data fusion from hand-written Arabic text implemented with MATLAB.

Hand-written text recognition is useful for interpreting records in different fields such as healthcare, surgery and police in which professionals may avoid technical equipment and prefer writing notes on paper. In order to perform data fusion from different data sources, handwriting automatic recognition involves barriers such as different ways of writing letters and deformation due to many reasons. This work presents a novel handwriting recognition approach based on the application of coordinate vectors to find similarities in different kinds of deformations. In particular, it has been implemented using 16 segments in order to distinguish all the particularities in matching the new text considering a dataset with a machine-learning approach. The implementation of this approach with MATLAB shows promising results with accuracy of 92.8% for with ensemble and bagged trees, after analyzing 22 possible combinations of machine learning and processing techniques.

Study on Percutaneous Intramedullary Nailing In Adult Diaphyseal Humeral Fractures

Objective: The objective of this research was to evaluate close fixation techniques for fractures of humerus via percutaneous intramedullary nailing.
 Methodology: This was a prospective study, carried out in Suleman Roshan Medical College Tando Adam Pakistan from January 2019 to January 2020. About 60 patients with humeral shaft fractures were made part of this study with a follow-up period of about 1 to 2 years. The inclusion criteria were humeral fractures that were of less than 7 days prior to surgery, the displacement of fracture >20° in sagittal as well as coronal plane, and the distance measuring >2cm between the two fragments. All patients were treated via the closed fixation technique. Multiple nails that were slender as well as flexible (3-5) were used in the close fixation technique including rush nails (45 patients) and ender nails (15 patients). All the patients within their follow-up periods were evaluated for ROM, pain, or any kind of deformity, and all the patients were assessed radiographically to check the process of bone union.
 Results: The outcome was analyzed before implant i.e at six months and after the implant was removed. About 86% patients (n= 52) revealed satisfactory outcomes at six months. About 5 patients revealed non-union or delayed union that was healed after 2nd surgery of bone grafting in 3 patients and injections associated with bone marrow in 2 patients. Stiffening of the shoulder was found to be a frequent complication that decreased significantly when the position of nail insertion was changed during the research.
 Conclusion: The technique of intramedullary nailing displayed many benefits including minimum tissue stress, a quick surgery time, decreased period of hospital stay, and rapid bone union.

«ХОРОША» І «ПОГАНА» ЛЮДИНА: ОСОБЛИВОСТІ КАТЕГОРИЗАЦІЇ ОСОБИСТОСТІ ДОРОСЛИМИ ВЕБКОРИСТУВАЧАМИ

Scientific problem and relevance. The novelty and active introduction of digital technologies make psychological studies of the Internet impact on users of different age groups relevant. The study covers adult and senior age groups, whose psychological formation finished during the pre-digital era. Aim. The paper aims to reveal the specifics of a categorical structure of adult web-users’ consciousness regarding social perception. Methods. The results of an empirical research carried out in the tradition of the cognitive approach are as follows. The study involved 600 respondents. All the respondents were representatives of the intellectual labor and are from 35 to 60 years. Using an open-ended questionnaire, the respondents were divided into two contrasting groups: “the reading subjects” and “the active Internet users” (n=100 each). Modeling of the categorical structure of the respondents’ consciousness was carried out through the factor analysis. As the incentive material, the assessments of the features of a “good” and “bad” person were used. The leading criterion of the complexity of consciousness is the quantity of the categories that form the concept. Main results. The main conclusions are that the reading subjects have a more complex cognitive structure in the categorization of a personality. There are two parameters that indicate this complexity: the quantity of the categories that form the concept, and the quantity of the categories with a bipolar internal organization (p=0.05). Sphere of application. The data can state the rationale of online activity restrictions of adult Internet users. Conclusion. A simplification of a categorical structure in social cognition among the active Internet users can be a kind of deformation because of Internet impact.

INITIAL AND RESIDUAL RESOURCE OF RUBBER-CORD SHELLS OF CONNECTING DEVICES OF ROLLING STOCK

In article the basic settlement dependences of a resource rubber-cord environments are given on the basis of the received results of experimental researches of integrated characteristics in view of quasi-elastic, not elastic and total deformation. Diagrams of dependence of durability of environments from a corner of a twisting and the specified kinds of deformation are constructed.

Soviet Trade in the 1960s — 1980s: Basic Principles and Their Distortion

The article reveals the problem of distortion of the socialist principles of Soviet trade in the economic practice of the state of the 1960s — 1980s, which is insufficiently illuminated in historical science, using the example of letters from Soviet citizens collected in the fund of the Russian State Archive of Contemporary History. Based on a review of a significant amount of archival sources, various kinds of deformations occurring in trade activities and their fixation in the public mind are demonstrated. It is emphasized that people’s ideas were the most important dimensions of social life, the economic dynamics of Soviet society and the social psychology of citizens. Particular attention is paid to the analysis of legislation as the main mechanism for regulating the development of the trade and economic area. It is argued that the lack of formation of the regulatory framework gave rise to such reality phenomena as deficit, overcharging, short weight and measurement of buyers, squandering, embezzlement, robbing and theft of property, black market turnover. The circumstances of the incorporation of the phenomenon of fellowship and nepotism into the stable custom of everyday life are commented. The author comes to the conclusion that class conflicts emerged in the socio-economic structure of Soviet society in the 1960s — 1980s, while the urgent facts of the system’s crisis were generated by the duality of the line of power.

Magnetorheological elastomers — An underestimated class of soft actuator materials

In this paper, the results of various investigations on the viscoelastic and magnetic properties of magnetorheological elastomers (MRE) in magnetic fields of variable strength, are reported. These characteristics have a strong influence on the behavior of MRE in various applications such as vibration damping and tunable vibration absorbers. Moreover, the actuation capabilities of MRE with different kinds of deformation in a magnetic field are considered. The degree of deformation depends on the magnetic field strength and its gradient and can reach about 10%. When removing the magnetic field, the MRE body relaxes back to its initial shape. MRE materials can be used for linear actuators, where the MRE body is deformed due to the attraction by a magnetic circuit acting from one side. Such linear actuators may be applied for haptic feedback and pumps. However, ring-shaped MRE bodies can also deform radially around their cylindrical axis, if the magnetic field is oriented correspondingly. This unusual type of deformation allows the realization of a proportional valve, whose opening is controlled by the magnetic field strength. Similar configurations can be used for controllable seals, for locking devices and even for inchworm drives. Various versions of this actuation principle are discussed in the paper.

ОПРЕДЕЛЕНИЕ ПОКАЗАТЕЛЕЙ ВЗАИМОДЕЙСТВУЮЩИХ ПОДСИСТЕМ ПРОМЫШЛЕННЫХ ПРЕДПРИЯТИЙ ДЛЯ ДОСТИЖЕНИЯ ЦЕЛЕЙ В ОБЛАСТИ КАЧЕСТВА

Highways are the most important component of country's economic development. They are a complex of engineering structures that are subject to various kinds of deformations during operation. The causes of premature defects are outdated technologies, poor quality materials, high traffic loads, and weather conditions. On average, after 2–3 years of the new road operation, pits, overflows, potholes, cracks, rutting occur on asphalt concrete pavement, its presence worsens the traffic conditions on the road and violates the unimpeded passage of cars. To extend the life cycle of a transport object, there are preventive measures that prevent the destruction of road surfaces. Such activities include regular maintenance and repair work. One of the effective measures is the use of road impregnation materials (RIM). Road-impregnation materials are used in case of need to prevent aging of the organic binder in the composition of asphalt concrete in the coating, as well as to reduce the impact of external factors. In this article, the influence of the basis of the impregnating material of two manufacturers on the indicators of the properties of asphalt concrete of various degrees of destruction is investigated. Among the considered impregnating compositions, solvent-based road impregnation materials proved to be the most effective. It has been established that the abrasive effect on samples of asphalt concrete significantly reduces the effectiveness of impregnating materials, especially based on bitumen emulsion.

Effect of pre-deformation before aging on discontinuous precipitation behaviour in Cu-Ni-Si alloys

ABSTRACT The effect of deformation before aging on discontinuous precipitation in Cu–4.75wt%Ni–1.13wt%Si and Cu–6wt%Ni–1.42wt%Si alloys after solution treatment was investigated. Two kinds of deformation, one under and the other over the uniform deformation limit were implemented after solution treatment. With increasing deformation strain in both alloys, the discontinuous precipitation is accelerated and the aging time for a fully covered region by discontinuous precipitation is shortened. However, the Cu–6wt%Ni–1.42wt%Si alloy deformed under the uniform deformation limits showed an enhanced discontinuous precipitation compared to that for the alloy deformed over the uniform deformation limit. The deformation defects including dislocations and shear bands play the role of encouraging discontinuous precipitation. The shear bands formed during prior deformation beyond the necking point could provide sites for discontinuous precipitation initiation in the early stages of annealing However, shear bands tend to hinder the advance of discontinuous precipitation with further aging in the Cu–Ni–Si alloy with a high content of Ni and Si.

Traumatic Boutonnière Deformity of the Thumb

AbstractTwo Cases Of Boutonnière Deformity After Trauma Are Presented In Patients Without Rheumatic Disease. One Of Them Suffered An Assault and the other a high-energy accident. Both cases were misdiagnosed. The first case presented an injury of the dorsoradial capsule of the metacarpophalangeal (MCP) joint and the second case presented an injury of the adductor pollicis (AP) which is an unusual finding regarding this kind of deformity. The surgical treatment failed up to two times in the first case hile in the second case it failed once.

Role of Legislative Drafting in Victimization of Citizens

“It is the spirit and not the form of law that keeps justice alive - Earl Warren When drafting legislation, the drafter’s primary duty is to give effect to the policy of the sponsors of the law, but it is important for the drafter to have in mind the category of people who will read and use the legislation. It is also worth noting that when drafting legislation, a drafter should ensure clarity, precision and un-ambiguity. A drafter bears an obligation to maintain the rule of law. As part of this burden, a drafter must take care that the form of the law lends itself to clarity, precision and consistency. For without clarity, precision and consistency the law has no predictability. The rule of law demands that as much as is possible, people should know in advance what the law demands of them, what the law grants to them and what sorts of behavior they can expect from officials. It is therefore important that the drafter makes the law as simple and as clear as possible. This can only be achieved by employing the aspects of clarity, precision and un-ambiguity when drafting legislation. This research paper examines role of the drafts-person in the legislative process. The services of a parliamentary counsel are utilized from the stage of making policy and drafting it in the form of legislative provisions. The main role of parliamentary counsel is to give proper shape to the policies of the Government into legal provisions with adequate teeth for implementation. The legislative counsel should have sound knowledge of law and legal principles. The qualities of legislative drafters as well as the various stages of the drafting process are described with particular reference to the position in India. Ultimately the task of drafts-person is to help the country to have precise, readable and easily understandable laws useful to, and usable by the public to know and enforce their rights and privileges, perform their duties and be aware of their liabilities. If there would be any kind of deformity or loophole in legislative drafting by drafts-person then this would of course will lead to the victimization of citizens.