Processing Conditions in the Batch-Operated Internal Mixer

1975 ◽  
Vol 48 (3) ◽  
pp. 462-494 ◽  
Author(s):  
H. Palmgren
Keyword(s):  
General Purpose ◽  
Future Research ◽  
Processing Conditions ◽  
Mixing Process ◽  
Efficient Utilization ◽  
Rubber Mixer ◽  
Internal Mixer ◽  
Labor Utilization ◽  
Efficiency And Productivity ◽  
Principal Elements

Abstract This review represents an attempt to summarize and discuss some of the literature on the batch operated internal rubber mixer, with the primary view of studying processing conditions and how they influence efficiency and productivity of the process. The scope does not include materials to be mixed, their physical state, order of loading the mixer, compounding principles, systems layout, machine design, automation, mechanization, labor utilization, or other aspects of the mixing process. The discussion is limited to mixing and processing conditions connected with typical compounds, normally based on general-purpose rubbers, which today comprise by far the largest share of rubber batches mixed. It is assumed that the reader is acquainted with the mixing process and with rubber technology in general. The principal elements of the internal rubber mixer are sketched in Figure 1. Some scattered and not very coherent data on important makes of rubber mixers are collected in Tables II, III and IV and referred to in the following discussions. Since the different machines may have different applications, caution should be used in making intercomparisons. It is hoped that this review will contribute to the understanding of the mixing process, and its efficient utilization. A list of problem areas is presented at the end with the hope of stimulating future research.

THE ORIGINS OF MUSIC: INNATENESS, UNIQUENESS, AND EVOLUTION

2005 ◽  
Vol 23 (1) ◽  
pp. 29-59 ◽  
Author(s):  
JOSH McDERMOTT ◽  
MARC HAUSER
Keyword(s):  
Side Effects ◽  
Music Perception ◽  
Comparative Psychology ◽  
General Purpose ◽  
Adaptive Significance ◽  
Future Research ◽  
Relative Pitch ◽  
The Past ◽  
Evolution Of Music ◽  
Basic Features

THE ORIGINS and adaptive significance of music, long an elusive target, are now active topics of empirical study, with many interesting developments over the past few years. This article reviews research in anthropology, ethnomusicology, developmental and comparative psychology, neuropsychology, and neurophysiology that bears on questions concerning the origins and evolution of music. We focus on the hypothesis that music perception is constrained by innate, possibly human- and musicspecific principles of organization, as these are candidates for evolutionary explanations. We begin by discussing the distinct roles of different fields of inquiry in constraining claims about innateness and adaptation, and then proceed to review the available evidence. Although research on many of these topics is still in its infancy, at present there is converging evidence that a few basic features of music (relative pitch, the importance of the octave, intervals with simple ratios, tonality, and perhaps elementary musical preferences) are determined in part by innate constraints. At present, it is unclear how many of these constraints are uniquely human and specific to music. Many, however, are unlikely to be adaptations for music, but rather are probably side effects of more general-purpose mechanisms. We conclude by reiterating the significance of identifying processes that are innate, unique to humans, and specific to music, and highlight several possible directions for future research.

scholarly journals Nurturing Grandchildren With Down Syndrome: A Qualitative Study on Grandparents’ Needs Using Digital Tools†

2021 ◽  
Vol 12 ◽  
Author(s):  
María C. Sánchez Gómez ◽  
Rocío Martín-Sevillano ◽  
María V. Martín-Cilleros ◽  
J. J. Mena Marcos ◽  
Francisco J. García-Peñalvo
Keyword(s):  
Down Syndrome ◽  
General Purpose ◽  
Future Research ◽  
Personal Perspective ◽  
Social Emotional ◽  
Individual Interviews ◽  
Open Questions ◽  
Future Research Directions ◽  
Qualitative Phenomenological ◽  
Negative Feelings

Grandparents who have grandchildren with disabilities are an underrepresented group in existing research related to the field. This qualitative phenomenological study’s general purpose is to analyze, from a personal perspective, the situations and needs of grandparents who have grandchildren with Down syndrome. The participants’ ages range from 65 to 85, and the ages of their grandchildren with Down syndrome range from 3 to 21 years. All participants had one grandchild with a disability, except for two, who each had two. A sociodemographic questionnaire was administered, and individual interviews were conducted, using open questions, through phone and/or video calls. An analysis of the participants’ speech was carried out, which implied the development of a system of meta-categories and categories. This analysis was developed manually, given the COVID-19 environment. The results indicate a substantial change from negative feelings caused by the knowledge of the diagnosis to feelings related to positive experiences expressed currently. The participants see themselves as a fundamental source of support (informal, instrumental, practical, social, emotional, and economic) for their families and, mainly, for their grandchildren with Down syndrome. A need for information and training was observed when the grandparents talked about first being informed of the diagnosis and their concerns about the future of these grandchildren and their siblings. They made social demands, such as greater government involvement or more significant opportunities to access resources and rights for their grandchildren. The results are discussed, as are possible future research directions.

A Succinct Analysis of Applications and Services Provided by IoT

2018 ◽  
pp. 142-162
Author(s):  
Sushruta Mishra ◽  
Hrudaya Kumar Tripathy ◽  
Brojo Kishore Mishra ◽  
Sunil Kumar Mohapatra
Keyword(s):  
Internet Of Things ◽  
Future Internet ◽  
Physical World ◽  
Future Research ◽  
The Internet ◽  
Research Areas ◽  
Use Of Services ◽  
Potential Applications ◽  
Technical Features ◽  
Efficiency And Productivity

The phrase Internet of Things (IoT) heralds a vision of the future Internet where connecting physical things, from banknotes to bicycles, through a network will let them take an active part in the Internet, exchanging information about themselves and their surroundings. This will give immediate access to information about the physical world and the objects in it leading to innovative services and increase in efficiency and productivity. In general, it may be beneficial to incorporate a number of the technologies of IoT with the use of services that can act as the bridge between each technology and the applications that developers wish to implement in IoT. This chapter studies the state-of-the-art of IoT and presents the key potential applications, challenges and future research areas in the domain of IoT. This chapter presents four main categories of services according to technical features. Some major issues of future research in IoT are identified and discussed briefly.

Methodology for the Prediction of Complex Skill Performance

1975 ◽  
Vol 19 (1) ◽  
pp. 140-144
Author(s):  
Dale M. Dannhaus ◽  
Charles G. Halcomb
Keyword(s):  
Discrimination Task ◽  
Behavioral Assessment ◽  
Memory Task ◽  
Vigilance Task ◽  
General Purpose ◽  
Velocity Estimation ◽  
Future Research ◽  
Estimation Task ◽  
Complex Skill ◽  
Skill Performance

There has been a long and continuing interest in psychomotor batteries as a viable means to improve behavioral assessment and prediction in a variety of task situations. The present paper describes the conceptual framework and a methodology which contributed to the development of a general purpose psychomotor battery. The tasks which comprise the psychomotor battery at the present time include a velocity estimation task, a four-choice discrimination task, an auditory vigilance task, and a recognition memory task. A description of each task within the battery is presented. Research on the battery has suggested the potential usefulness of the battery as a predictor of complex skill performance. A summary of the research which has been conducted on the psychomotor battery, as well as future research planned, are discussed.

Processing Characteristics of Synthetic Rubbers and Their Use in the Manufacture of Extruded Products

1944 ◽  
Vol 17 (4) ◽  
pp. 932-940 ◽  
Author(s):  
A. E. Juve
Keyword(s):  
Natural Rubber ◽  
Present Situation ◽  
General Purpose ◽  
High Dispersion ◽  
High Recovery ◽  
Vulcanized Rubber ◽  
Roll Mill ◽  
The Difference ◽  
Extruded Products ◽  
Internal Mixer

Abstract The difference in processing behavior between synthetic rubbers and natural rubber becomes evident when production facilities designed for processing natural rubber are used for synthetic rubbers. All the synthetic rubbers in one respect or another are harder to process than natural rubber. Under circumstances other than the present emergency, processing equipment suitable for handling the synthetic rubbers would gradually be evolved. In the present situation, synthetic rubbers must be processed with equipment already available. In this discussion natural rubber and the general purpose synthetic rubbers, GR-S, GR-M and GR-I, will be considered. The processing of dry rubber consists essentially of the incorporation of vulcanizing agents, pigments, oils, and other ingredients by a process of kneading, followed by the forming of the mix by extrusion or calendering into shapes suitable for fabrication preparatory to final cure. The mixing step, which is accomplished on a two-roll mill or in an internal mixer, requires that the rubber be within a plasticity range that will permit satisfactory dispersion of the ingredients. If the plasticity is too low the rubber tends to crumble, and if it is too high dispersion is poor. Crude natural rubber is quite tough, and before breakdown has some of the properties of vulcanized rubber, such as high recovery after moderate distortion. In the crude state it is extremely difficult to obtain satisfactory dispersion of pigments. It is therefore necessary to soften it by mastication or other means so that the pigments are more readily incorporated and power requirements are lowered. In addition, its nerve or tendency to recover after distortion is greatly reduced. Synthetic rubbers, in general, differ from natural rubber in their susceptibility to softening by mastication, and they show different relationships between nerve and plasticity than does natural rubber.

Numerical Modeling of Spiral Micro-Mixers

2009 ◽  
Vol 74 ◽  
pp. 327-330
Author(s):  
Yong Jun Wee ◽  
Ai Qun Liu ◽  
Ren Jian Gan
Keyword(s):  
Numerical Modeling ◽  
Particle Separation ◽  
General Purpose ◽  
Mixing Process ◽  
Robust Solution ◽  
Mixing Performance ◽  
Multiple Phase ◽  
Mixer Design ◽  
Continuous Particle ◽  
Micro Mixer

Optimization of micro-mixing components is vital for efficient micro-electromechanical systems (MEMS) and lab-on-a-chips. In this area, it is ideal to have a universal micro-mixer design for general purpose multiple-phase fluidic mixing. Numerical methods to compute and analyze the mixing process in the spiral micro-mixer design are presented. This spiral design has also been found to be efficient for intra-droplet mixing as well as continuous particle separation by utilizing its attributing Dean flows. Analysis on the mixing performance of this design serves to present Archimedes’ spiral as a robust solution and exemplifies the effects of minute yet effective alterations to the design.

scholarly journals Effects of equipments and processing conditions on quality of fresh-cut produce

2018 ◽  
Vol 49 (3) ◽  
pp. 139-150
Author(s):  
Francisca Aba Ansah ◽  
Maria Luisa Amodio ◽  
Maria Lucia Valeria De Chiara ◽  
Giancarlo Colelli
Keyword(s):  
Global Market ◽  
Leafy Vegetables ◽  
Future Research ◽  
Processing Conditions ◽  
Minimal Processing ◽  
Wide Range ◽  
Fresh Cut ◽  
Precautionary Measures ◽  
Processed Products

A wide range of fresh conveniently packaged, minimally processed products are available on both local and global market in response to consumer demand for ready to eat food. Majority of these products are leafy vegetables, which are highly susceptible to quality changes during minimal processing operations (trimming, cutting, washing, drying, and packaging). Despite the available precautionary measures for maintaining quality attributes of raw and processed material, quality degradation due to minimally processing is unavoidable, also considering that a peeling, trimming and/or cutting operation is always present except than for baby leaves and small fruits. In addition, other operations as washing and drying are known to cause mechanical stresses and loss of sugars and nutrients. However, the extent to which quality is compromised depends on the produce and on the processing conditions, including equipment and their operational settings. This review aims to describe the main processing operations and equipment used, resuming the available information on their impact on final quality of fresh-cut products over storage, in order to identify areas for future research aiming to the enhancement of product quality

scholarly journals Role Ambiguity in Sport Teams

2003 ◽  
Vol 25 (4) ◽  
pp. 534-550 ◽  
Author(s):  
Mark A. Eys ◽  
Albert V. Carron ◽  
Mark R. Beauchamp ◽  
Steven R. Bray
Keyword(s):  
Role Ambiguity ◽  
A Priori ◽  
Operational Definition ◽  
General Purpose ◽  
Future Research ◽  
First Year ◽  
Individual Level ◽  
Sport Teams ◽  
Definition Of ◽  
The Individual

The general purpose of the present study was to examine the nature of role ambiguity in sport teams and to explore the construct validity of the operational definition of role ambiguity developed by Beauchamp, Bray, Eys, and Carron (2002). Role ambiguity was operationalized as a multidimensional construct (Scope of Responsibilities, Behavioral Responsibilities, Evaluation of Performance, and Consequences of Not Fulfilling Responsibilities) that occurs in two contexts, offense and defense. Consistent with the a priori hypothesis, perceptions of role ambiguity exhibited some degree of within-group consistency and group-level variability, but most of the variance in role ambiguity was seen at the individual level. Also, perceptions of role ambiguity decreased from early to late season. Finally, veteran athletes experienced less role ambiguity than first-year athletes at the beginning of the season, but not at the end. Implications of the findings and suggestions for future research are discussed.

SWING OPTION PRICING BY DYNAMIC PROGRAMMING WITH B-SPLINE DENSITY PROJECTION

2019 ◽  
Vol 22 (08) ◽  
pp. 1950038
Author(s):  
J. LARS KIRKBY ◽  
SHI-JIE DENG
Keyword(s):  
Dynamic Programming ◽  
Cash Flows ◽  
General Purpose ◽  
Future Research ◽  
Unified Framework ◽  
Swing Options ◽  
Early Exercise ◽  
Swing Option ◽  
Financial Derivative ◽  
Exponential Lévy Models

Swing options are a type of exotic financial derivative which generalize American options to allow for multiple early-exercise actions during the contract period. These contracts are widely traded in commodity and energy markets, but are often difficult to value using standard techniques due to their complexity and strong path-dependency. There are numerous interesting varieties of swing options, which differ in terms of their intermediate cash flows, and the constraints (both local and global) which they impose on early-exercise (swing) decisions. We introduce an efficient and general purpose transform-based method for pricing discrete and continuously monitored swing options under exponential Lévy models, which applies to contracts with fixed rights clauses, as well as recovery time delays between exercise. The approach combines dynamic programming with an efficient method for calculating the continuation value between monitoring dates, and applies generally to multiple early-exercise contracts, providing a unified framework for pricing a large class of exotic derivatives. Efficiency and accuracy of the method are supported by a series of numerical experiments which further provide benchmark prices for future research.

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