scholarly journals Digitalization of Human Operations in the Age of Cyber Manufacturing: Sensorimotor Analysis of Manual Grinding Performance

2017 ◽  
Vol 139 (10) ◽  
Author(s):  
Gregory L. Bales ◽  
Jayanti Das ◽  
Jason Tsugawa ◽  
Barbara Linke ◽  
Zhaodan Kong
Keyword(s):  
Motor Behavior ◽  
Removal Rate ◽  
Workforce Training ◽  
Specific Knowledge ◽  
New Techniques ◽  
Manual Task ◽  
Applied Forces ◽  
Large Repertoire ◽  
Experienced Subject ◽  
Different Levels

This paper presents new techniques to analyze and understand the sensorimotor characteristics of manual operations such as grinding, and links their influence on process performance. A grinding task, though simple, requires the practitioner to combine elements from the large repertoire of his or her skillset. Based on the joint gaze, force, and velocity data collected from a series of manual grinding experiments, we have compared operators with different levels of experience and quantitatively described characteristics of human manual skill and their effects on manufacturing process parameters such as cutting energy, surface finish, and material removal rate (MRR). For instance, we find that an experienced subject performs the task in a precise manner by moving the tool in complex paths, with lower applied forces and velocities, and short fixations compared to a novice. A detailed understanding of gaze-motor behavior broadens our knowledge of how a manual task is executed. Our results help to provide this extra insight, and impact future efforts in workforce training as well as the digitalization of manual expertise, thereby facilitating the transformation of raw data into product-specific knowledge.

EFFECT OF ABRASIVE TYPE ON THE SURFACE ROUGHNESS AND MRR IN MAF OF AISI 304 STEEL

2021 ◽  
Author(s):  
MAHMUT ÇELIK ◽  
HAKAN GÜRÜN ◽  
ULAŞ ÇAYDAŞ
Keyword(s):  
Surface Roughness ◽  
Removal Rate ◽  
Three Dimensional ◽  
Steel Plates ◽  
304 Stainless Steel ◽  
Average Surface Roughness ◽  
Machining Time ◽  
Aisi 304 ◽  
Average Surface ◽  
Different Levels

In this study, the effects of experimental parameters on average surface roughness and material removal rate (MRR) were experimentally investigated by machining of AISI 304 stainless steel plates by magnetic abrasive finishing (MAF) method. In the study in which three different abrasive types were used (Al2O3, B4C, SiC), the abrasive grain size was changed in two different levels (50 and 80[Formula: see text][Formula: see text]m), while the machining time was changed in three different levels (30, 45, 60[Formula: see text]min). Surface roughness values of finished surfaces were measured by using three-dimensional (3D) optical surface profilometer and surface topographies were created. MRRs were measured with the help of precision scales. The abrasive particles’ condition before and after the MAF process was examined and compared using a scanning electron microscope. As a result of the study, the surface roughness values of plates were reduced from 0.106[Formula: see text][Formula: see text]m to 0.028[Formula: see text][Formula: see text]m. It was determined that the best parameters in terms of average surface roughness were 60[Formula: see text]min machining time with 50[Formula: see text][Formula: see text]m B4C abrasives, while the best result in terms of MRR was taken in 30[Formula: see text]min with 50[Formula: see text][Formula: see text]m SiC abrasives.

CONSTANT AND VARIABLE IN THE STYLE OF A RUSSIAN PIANO QUARTET

2020 ◽  
Vol 1 (2) ◽  
pp. 69-74
Author(s):  
N. K. Samoilova ◽  
Keyword(s):  
Chamber Music ◽  
New Techniques ◽  
Functional Roles ◽  
Russian Music ◽  
Piano Quartet ◽  
Music Making ◽  
The Difference ◽  
The Stability ◽  
Transformation Processes ◽  
Different Levels

The process of the steady rooting of invariant genre features of a piano quartet is considered through the ratio between stable and mobile features. Here there is either the complete independence of the instruments, but on the principles of equal participation in the embodiment of musical content, or the variability in the relations of instrumental parts. As the main ones in the genre, the musical norms of the classic-romantic style and the stability of the timbre composition are established. It is noted that in Russian music the evolution of the piano quartet passed through different phases: genre stabilization and recovery, temporary stop and subsequent active development. Transformation processes went through different levels: structure, content, instrumental- timbre solutions, rethinking the functional roles of partner instruments. The movement from the traditional normativity of instrumental compositions to the difference of timbre combinations in the XXth–XXIst centuries was primarily predetermined by such factors as polyphonization of texture, the active introduction of polyphonic forms, new techniques of instrumentation. In the modern piano quartet, the central idea of chamber music making, the idea of co-creation generates both an extremely individualized form of embodiment and a free timbre composition. In conclusion, it is noted that the piano quartet genre has the ability to accumulate the leading style trends in chamber music of different eras.

Lima, João Filgueiras "Lelé" (1932–2014)

2018 ◽  
Author(s):  
Rafael Urano Frajndlich
Keyword(s):  
Integrated Approach ◽  
Public Works ◽  
Industrial Building ◽  
Construction Sites ◽  
New Techniques ◽  
Locomotor System ◽  
The Public ◽  
Building Components ◽  
Industrial Materials ◽  
Different Levels

João "Lelé" Filgueiras Lima is a public architect. Since his formative years on the construction sites of Brasília (1960) until today, his most remarkable works have been created for the public sector. This aspect of his career led him to take a very plastic approach that always relied upon economical building strategies, and often required new techniques and industrial materials. Lelé’s interest in industrial building components led him to design pieces of his own, which were used in some early public works, such as the Taguatinga Hospital (1965) and the Secretariats of Bahia Administration Center (1973). Lelé’s breakthrough came when he designed hospitals for the SARAH Kubitschek Foundation. For Brasília’s Hospital for Diseases of the Locomotor System (1980), he used an integrated approach to fulfill the normative standards for a rehabilitation facility, to keep to a tight budget, and to create shade from the extreme heat of Brasília. A gap between the different levels allows all the recovery rooms to have access to a well-shaded green terrace. Structures and cladding are made from prefabricated reinforced concrete, articulated by one-storey-high Virendell beams.

scholarly journals Neuroimaging in aging: brain maintenance

F1000Research ◽  
2017 ◽  
Vol 6 ◽  
pp. 1215 ◽  
Author(s):  
Lars Nyberg
Keyword(s):  
Multimodal Imaging ◽  
Longitudinal Design ◽  
Older Age ◽  
Aging Brain ◽  
Brain Pathology ◽  
New Techniques ◽  
Relative Lack ◽  
Brain Maintenance ◽  
Critical Task ◽  
Different Levels

Neuroimaging studies of the aging brain provide support that the strongest predictor of preserved memory and cognition in older age is brain maintenance, or relative lack of brain pathology. Evidence for brain maintenance comes from different levels of examination, but up to now relatively few studies have used a longitudinal design. Examining factors that promote brain maintenance in aging is a critical task for the future and may be combined with the use of new techniques for multimodal imaging.

scholarly journals New Techniques in Diagnosis of Eye Muscle Palsies: A Review

1980 ◽  
Vol 73 (2) ◽  
pp. 115-122 ◽  
Author(s):  
A Huber
Keyword(s):  
The Other ◽  
Eye Muscle ◽  
New Techniques ◽  
Pathological Conditions ◽  
Saccadic Velocity ◽  
The One ◽  
Different Levels ◽  
Important Indication ◽  
Degree Of Recovery

New techniques of diagnosis of eye muscle palsies are discussed. Electromyography facilitates differentiation between myopathies, myasthenias, neurogenic palsies and supranuclear motility disorders; this differentiation is based on the different aspects of electromyograms according to the different levels of affection. An important aid in diagnosis of eye muscle palsies, especially for the observation of the course of eye muscle palsies is oculography: here the determination of different parameters of eye movements under normal and pathological conditions is of utmost importance. These parameters are saccadic velocity on the one hand and acceleration on the other. Oculographic measurement of the saccadic movements gives a valuable indication of the severity of an eye muscle palsy and, when repeated, provides an important indication of the degree of recovery. A combination of electromyography and oculography permits the innervational pattern or eye muscles to be correlated with certain types of movements under normal and pathological conditions (Figure 9).

Industry-Specific Knowledge Transfer in Audit Firms: Evidence from Audit Firm Mergers in China

2021 ◽  
Author(s):  
Xianjie He ◽  
S.P. Kothari ◽  
Tusheng Xiao ◽  
Luo Zuo
Keyword(s):  
Treatment Group ◽  
Knowledge Transfer ◽  
Audit Quality ◽  
Control Group ◽  
Specific Knowledge ◽  
Difference In Differences ◽  
Audit Firm ◽  
Audit Firms ◽  
Financial Misstatements ◽  
Different Levels

Using a difference-in-differences approach, we examine the effect of industry-specific knowledge transfer on audit performance after a merger of two Chinese audit firms with different levels of expertise in an industry. For clients in an industry audited by both merging audit firms, those audited by the audit firm less specialized in that industry belong to the treatment group, while all other clients belong to the control group. We find an economically-significant improvement in audit quality (as reflected in a reduction in financial misstatements) for the treatment group relative to the control group in the same merged audit firm. We show that the treatment effect is not driven by changes in auditor incentives or personnel movement and is more pronounced when we expect stronger communication between the less and more specialized auditors after the merger. We caution that our findings are specific to China and may not generalize to other countries.

scholarly journals Integrating Operator Information for Manual Grinding and Characterization of Process Performance Based on Operator Profile

2018 ◽  
Vol 140 (8) ◽  
Author(s):  
Jayanti Das ◽  
Gregory L. Bales ◽  
Zhaodan Kong ◽  
Barbara Linke
Keyword(s):  
Tool Path ◽  
Removal Rate ◽  
Specific Energy Consumption ◽  
Multivariate Regression Analysis ◽  
Processing Parameters ◽  
Quality Analysis ◽  
Process Performance ◽  
Machined Surface ◽  
Applied Forces ◽  
Visual Gaze

Due to its high versatility and scalability, manual grinding is an important and widely used technology in production for rework, repair, deburring, and finishing of large or unique parts. To make the process more interactive and reliable, manual grinding needs to incorporate “skill-based design,” which models a person-based system and can go significantly beyond the considerations of traditional human factors and ergonomics to encompass both processing parameters (e.g., feed rate, tool path, applied forces, material removal rate (MRR)), and machined surface quality (e.g., surface roughness). This study quantitatively analyzes the characteristics of complex techniques involved in manual operations. A series of experiments have been conducted using subjects of different levels of skill, while analyzing their visual gaze, cutting force, tool path, and workpiece quality. Analysis of variance (ANOVA) and multivariate regression analysis were performed and showed that the unique behavior of the operator affects the process performance measures of specific energy consumption and MRR. In the future, these findings can be used to predict product quality and instruct new practitioners.

scholarly journals Variation and Variability: Key Words in Human Motor Development

2010 ◽  
Vol 90 (12) ◽  
pp. 1823-1837 ◽  
Author(s):  
Mijna Hadders-Algra
Keyword(s):  
Motor Development ◽  
Motor Behavior ◽  
Behavioral Variability ◽  
Motor Disorder ◽  
Specific Situation ◽  
Neural Basis ◽  
Basic Principles ◽  
Human Motor ◽  
The One ◽  
Large Repertoire

This article reviews developmental processes in the human brain and basic principles underlying typical and atypical motor development. The Neuronal Group Selection Theory is used as theoretical frame of reference. Evidence is accumulating that abundance in cerebral connectivity is the neural basis of human behavioral variability (ie, the ability to select, from a large repertoire of behavioral solutions, the one most appropriate for a specific situation). Indeed, typical human motor development is characterized by variation and the development of adaptive variability. Atypical motor development is characterized by a limited variation (a limited repertoire of motor strategies) and a limited ability to vary motor behavior according to the specifics of the situation (ie, limited variability). Limitations in variation are related to structural anomalies in which disturbances of cortical connectivity may play a prominent role, whereas limitations in variability are present in virtually all children with atypical motor development. The possible applications of variation and variability in diagnostics in children with or at risk for a developmental motor disorder are discussed.

The syntax–lexicon continuum in Construction Grammar

2010 ◽  
Vol 24 ◽  
pp. 54-82 ◽  
Author(s):  
Hans C. Boas
Keyword(s):  
Semantic Analysis ◽  
Construction Grammar ◽  
Levels Of Abstraction ◽  
Alternative Analysis ◽  
Specific Knowledge ◽  
The Status ◽  
Different Levels ◽  
Syntactic Frames

This paper offers an alternative analysis of Goldberg’s (1995) account of communication verbs appearing in the ditransitive construction. Based on a more finely-grained frame-semantic analysis of constructional phenomena, it is shown that generalizations over specific syntactic frames are possible at different levels of semantic abstraction. This, in turn, allows us to make across-the-board generalizations that hold not only between lexical units evoking the same frame, but also between lexical units belonging to different frames at different levels of abstraction. The resulting network of constructions combines Goldberg’s proposals regarding the status of abstract-schematic constructions with item-specific knowledge regarding the specific lexical units, with various midpoints in between. This approach has the advantage that there is no need for fusing lexical entries with abstract meaningful constructions, thereby avoiding some of the problems that arise due to the separation of syntax and the lexicon in some constructional approaches.

Medicine and mineralogy

1977 ◽  
Vol 286 (1336) ◽  
pp. 585-592 ◽  
Keyword(s):  
General Public ◽  
Health Hazards ◽  
New Techniques ◽  
Present Evidence ◽  
The Past ◽  
New Man ◽  
Mineral Dusts ◽  
Micro Level ◽  
Fibrous Mineral ◽  
Different Levels

The article deals with the health hazards caused by mineral dusts, and by asbestos fibres in the induction of cancers in particular. Mineral dusts cause damage by inhalation, rarely by ingestion or ingress into the skin. In the lung, bronchitis, fibrosis (pneumoconiosis), and cancers may result. Few mineral dusts cause cancers, and asbestos is unique in causing two separate types within the lung. Epidemiological and other studies of groups of asbestos workers have shown important differences in risk with the type of fibre and the type of job. All types of asbestos cause fibrosis and an excess of bronchial cancers which are, however, also closely cigarette related. Crocidolite is especially related to cancers of the surface of the lung (mesotheliomas). Mining and milling of chrysotile, the most used type of asbestos, have caused few mesotheliomas, despite heavy dust exposures in the past. The diseases induced by asbestos are dose-related* Where it has been possible to divide the groups of asbestos workers into those with different levels of past exposure, the least exposed groups have shown small or no excess of asbestos-related diseases despite their exposures having been considerably higher than that likely to have been encountered by the general public. Present evidence indicates that the general public have not been at risk of asbestos-related diseases, but more evidence is required about the proportion of all mesotheliomas which are related to asbestos. The new techniques of mineralogy when applied at a micro level to the dust in tissues, and particularly in the lung, may be of great help in answering this important problem. Some comparisons of the mortality from occupationally related cancers, accidents, smoking habits, and general diseases are given. Current research into the biomedical effects of natural fibrous mineral dusts is likely to be of great value in ensuring that the new man made mineral fibres now being developed are manufactured and used under circumstances which will cause no ill effects to health.

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