Understanding Cooling Rate Response of Test Pieces and Actual Gears Using Heat Treat

The cooling history of carburized heat-treated gears plays a significant role in developing microstructure, hardness, and residual stress in the tooth that influences the fatigue performance of the gear. Evaluating gear carburizing heat treatment should include a microstructure and hardened depth evaluation. This can be done on an actual part or with a test piece. The best practice for a test piece is to use a section size that closely approximates the cooling rate at the gear flank of the actual gear. This study furthers work already presented showing the correct test piece size that should be used for different gear modules (tooth thicknesses). Metallurgical comparisons between test pieces, actual gears, and FEA simulations are shown.

DAGESTAN PROFESSIONAL MUSICAL ART IN HISTORICAL DEVELOPMENT: THE SECOND HALF OF THE XX - BEGINNING OF THE XXI CENTURY

The article describes the patterns and features of the development of the musical art of Dagestan at different stages of its evolution over more than half a century of history. We have analyzed the components of the musical and professional tradition, giving a holistic view of it, versatile reflecting both the originality and originality, and historical variability. These include: genre-species differentiation and systemic connections, stylistics and means of musical expression.The multifaceted study and the possibility of interpreting the data obtained allows one to create an idea of ​​the ways of the formation and development of the musical art of Dagestan during the period under consideration. The initial premises of the study can be summarized as follows.The structure of musical art is formed on the basis of the interrelationships of composer's creativity, performing practice and various cultural interchanges that undergo stylistic and genre-specific changes.The second premise was the look at the musical art of Dagestan as an actual part of modern culture. Therefore, the main source has become various forms of broadcasting musical culture (listening practice and analytical observations at concerts of classical music).Reliance on contemporary musical material and direct observation of the musical process in the field of classical, pop and other spheres of culture presupposes the study of the phenomenon in a synchronic aspect. The presence of publications by different authors and our own research experience make it possible to a certain extent to make diachronic comparisons.The important regularities in the development of the Dagestan academic musical art identified by us can form the basis for further research of genre phenomena in different historical periods.

A Multiple Default Domain: a Semantics- Based Account

The objective of this study is to examine the use of the Masculine Sound Plural (MSP) as a default inflection in Modern Standard Arabic (MSA). Twenty-six fourth-year university students in the department of Arabic language and literature participated in the experiment and they were required to provide the plural inflection for 30 derived noun forms in MSA. The data used in this study consists of agentive derived forms that indicate human action meaning. The descriptive statistics approach (mean and standard deviation) was used to investigate the data; the results of the current study showed that MSP inflection was produced in a higher rate of frequency than the other possible forms of the irregular plural inflectional forms-broken plural (BP)- inflection that can also be actual part of the lexicon or schemata or background knowledge. The findings of this study support the accounts provided by the combinatorial processing mechanism with a suffixation formation that is more predictable than any other BP forms. The results of this study also provide more concrete evidence on the idea that there is initial mapping between the semantic features and the emergence of the default inflection which primarily motivates the emergence of the default form, and this semantic mapping is expected to add more to the properties that make the multidefault scenario more possible.

Automatic assembly of micro-miniature parts based on coaxial alignment and ORB feature matching

Aiming at the problems of low manual assembly process efficiency and low yield of micro-miniature parts. A vision system based on ORB feature matching for fast coaxial alignment of micro-miniature parts automated assembly is proposed. The coaxial alignment module is the main hardware, the assembly part and the base part can be imaged in the industrial camera; the ORB features are extracted from the known part template image and the part image obtained by the vision imaging system, and the RANSAC algorithm is adopted to match the ORB features of the template image and the actual part image, the pose of parts is calculated by feature matching results. At the same time, the image coordinate system and the motion axis coordinate system are calibrated, and the motion control system is driven by the transformation matrix of the two coordinate systems to complete the assembly between the assembly part and the base part. The assembly experiment shows the system can complete the automated assembly of micro-miniature parts.

Overview of Gc Tests Used to Evaluate Composite–Composite Adhesive Joints

The quality of composite–composite bonded joints is a very important issue for industries, especially for the aerospace sector. A deficient joint may stop the manufacturing process and its repairing may include very high costs. Nowadays, the quality of the joint is obtained by means of interlaminar fracture toughness tests, estimating the [Formula: see text] value (Energy Release Rate used to produce crack propagation) over coupons with (theoretically) the same conditions as those included in an actual part. Usually, [Formula: see text] is obtained by means of a Double Cantilever Beam (DCB) test. Although DCB is the reference test, it may present some drawbacks when a non-symmetrical coupon is used and when the adherents stiffness is low. An alternative to DCB is the Climbing Drum Peel (CDP) test which is able to address some of the DCB drawbacks. Nevertheless, both tests need the use of a universal testing machine, then they cannot be done in situ. In the present investigation, DCB and CDP main characteristics are analyzed and a new device, called Horizontal Drum Peel (HDP), which includes the advantages of previous tests and the possibility to perform the test over an actual part is presented.

An Adaptive Geometry Transformation and Repair Method for Hybrid Manufacturing

Hybrid manufacturing has become particularly attractive for refurbishing of high-value freeform components. Components may experience unique geometric distortions and/or wear-driven material loss in service, which require the use of part-specific, adaptive repair strategies. The current work presents an integrated adaptive geometry transformation method for additive/subtractive hybrid manufacturing based on rigid and nonrigid registrations of parent region material and geometric interpolation of the repair region material. In this approach, rigid registration of nominal part geometry to actual part geometry is accomplished using iterative alignment of profiles in the parent material. Nonrigid registration is used to morph nominal part geometry to actual part geometry by transformation of the profile mean line. Adaptive additive and subtractive tool paths are then used to add material based on constant stock margin requirements, as well as to produce blend repairs with smooth transition between parent and repair regions. A range of part deformation conditions due to profile twist and length changes are evaluated for the case of a compressor blade/airfoil geometry. Accuracy of the resulting adaptive geometry transformation method were quantified by (1) surface comparisons of actual and transformed nominal geometry and (2) blend region surface accuracy. Performance of the adaptive repair strategy relative to a naïve strategy is evaluated by the consideration of material efficiency and process cycle time. It is shown that the adaptive repair strategy resulted in an increase in material efficiency by 42.2% and a decrease in process time by 17.8%, depending on the initial deformation imposed on the part geometry.

Mack the Knife and Knife-Black Dorothy Appositional Metaphoric Compounds: A Comparison and Contrast of the Varying Approaches in Sanskrit Treatises on Grammar and Poetics

The present article focuses on appositional metaphoric compounds karmadhāraya-rūpaka in Sanskrit. A first section addresses some problems of compound typology in Western works, where appositional compounds have often been identified as copulative dvandva. Following this general analysis there is a section on appositional compounds from the perspective of the classical Sanskrit grammar, in particular the Pāṇinian tradition where the metaphorical aspect has not been explored specifically. The final section deals with the contribution of Sanskrit treatises on poetics to the identification of metaphoric compounds and their differentiation from compound similes. The approach suggested in later texts on poetics seems to be based on syntactical criteria, the ambiguity of the double-head topic, i. e. candra-mukha, a moon-face being specified in the comment. According to this, an appositional compound should be analysed as a simile, if the comment refers to the actual part of the compound, i.e. the subject of the simile, or as a metaphor, if the comment refers to the standard of comparison, thus shifting the focus of the sentence from the actual to the imagined entity.

Study of Distortion on the Example of the Rings from Ductile Iron and Cast Steel

The paper attempts to analyze distortions of cast iron and cast steel rings, after heat treatment cycles. The factors influencing distortion are: chemical composition of material, sample geometry, manufacturing process, hardenability, temperature and heat treatment method. Standard distortion tests are performed on C-ring samples. We selected a ring-model, which approximate the actual part, so that findings apply to gear rings. Because distortion depends on so many variables, this study followed strictly defined procedures. The research was started by specifying the appropriate geometry of the samples. Then, the heat treatment was conducted and samples were measured again. The obtained results allow to determine the value of the resulting distortion and their admissibility. The research will be used to evaluate the possibility of using the material to produce parts of equipment operated under extreme load conditions.

Investigating Alignment Effect on Inspection Accuracy of AM Part Using 3D Scanner

Presently, parts having intricate custom-made profiles are mostly fabricated using additive manufacturing (AM) processes. It becomes an essential task to verify the accuracy of AM parts so that they meet customer’s need and requirement. In product quality control, quick error comparison of manufactured part and an original CAD model is usually laborious but still a critical issue. Noncontact inspections using 3D scanners were preferred over conventional coordinate measurements, due to the significant amount of point data capturing in very short span of time. One of the important step of the noncontact inspection procedure using the 3D scanner is the correct localization of the datum reference frame. This step would help in the effective alignment of the digitized point data. This paper takes into consideration various 3-2-1 alignment approaches and investigates their influence on the inspection results. The result provides an evidence that an incorrect description of the product reference frame can lead to erroneous estimation of actual part deviations. The results show higher distance distribution for most of the point data of third alignment as the distance distribution is influenced by the worst description of the part reference frame. On the contrary, second alignment shows least distance distribution among point data due to correct reference frame definition.