scholarly journals Simulation Verification of the Contact Parameter Influence on the Forces’ Course of Cereal Grain Impact against a Stiff Surface

2021 ◽  
Vol 11 (2) ◽  
pp. 466
Author(s):  
Włodzimierz Kęska ◽  
Jacek Marcinkiewicz ◽  
Łukasz Gierz ◽  
Żaneta Staszak ◽  
Jarosław Selech ◽  
...  
Keyword(s):  
Dynamic Properties ◽  
Decisive Role ◽  
Force Sensor ◽  
Contact Forces ◽  
Correct Selection ◽  
Contact Parameter ◽  
Cereal Grain ◽  
Wide Range ◽  
The Impact ◽  
Selection Of

The continuous development of computer technology has made it applicable in many scientific fields, including research into a wide range of processes in agricultural machines. It allows the simulation of very complex physical phenomena, including grain motion. A recently discovered discrete element method (DEM) is used for this purpose. It involves direct integration of equations of grain system motion under the action of various forces, the most important of which are contact forces. The method’s accuracy depends mainly on precisely developed mathematical models of contacts. The creation of such models requires empirical validation, an experiment that investigates the course of contact forces at the moment of the impact of the grains. To achieve this, specialised test stations equipped with force and speed sensors were developed. The correct selection of testing equipment and interpretation of results play a decisive role in this type of research. This paper focuses on the evaluation of the force sensor dynamic properties’ influence on the measurement accuracy of the course of the plant grain impact forces against a stiff surface. The issue was examined using the computer simulation method. A proprietary computer software with the main calculation module and data input procedures, which presents results in a graphic form, was used for calculations. From the simulation, graphs of the contact force and force signal from the sensor were obtained. This helped to clearly indicate the essence of the correct selection of parameters used in the tests of sensors, which should be characterised by high resonance frequency.

scholarly journals The Anti-Resonance Criterion in Selecting Pick Systems for Fully Operational Cutting Machinery Used in Mining

2017 ◽  
Vol 62 (4) ◽  
pp. 775-793 ◽  
Author(s):  
Piotr Cheluszka
Keyword(s):  
Dynamic Properties ◽  
Free Vibrations ◽  
Correct Selection ◽  
Cutting Head ◽  
Load Carrying ◽  
Mining Machinery ◽  
Main Components ◽  
The Impact ◽  
Cutting System ◽  
Selection Of

Abstrat This article discusses the issue of selecting a pick system for cutting mining machinery, concerning the reduction of vibrations in the cutting system, particularly in a load-carrying structure at work. Numerical analysis was performed on a telescopic roadheader boom equipped with transverse heads. A frequency range of the boom’s free vibrations with a set structure and dynamic properties were determined based on a dynamic model. The main components excited by boom vibrations, generated through the process of cutting rock, were identified. This was closely associated with the stereometry of the cutting heads. The impact on the pick system (the number of picks and their arrangement along the side of the cutting head) was determined by the intensity of the external boom load elements, especially in resonance zones. In terms of the anti-resonance criterion, an advantageous system of cutting head picks was determined as a result of the analysis undertaken. The correct selection of the pick system was ascertained based on a computer simulation of the dynamic loads and vibrations of a roadheader telescopic boom.

The cereal grain trade in the United Kingdom: the problem of cereal variety

1984 ◽  
Vol 304 (1120) ◽  
pp. 395-407 ◽  
Keyword(s):  
United Kingdom ◽  
Major Constituent ◽  
Variety Identification ◽  
Starch Gel Electrophoresis ◽  
Current Frequency ◽  
Growth Environment ◽  
The United Kingdom ◽  
Cereal Grain ◽  
Wide Range ◽  
The Impact

The production of cereals in the United Kingdom has increased steadily over recent years from 12.6 million tonnes in 1964 to 21.8 million tonnes in 1982. During this period, the United Kingdom’s accession to the E.E.C. in 1973 caused a reverse in the milling industry’s policy of including only a small proportion of home-grown wheat with imported wheat in breadmaking grists. Home-grown wheat is now the major constituent of mass produced bread. Since the passing of the Plant Varieties Rights Act in 1964, plant breeders have been able to collect royalties on the sale of seed of their varieties; this led within a decade to a large number of high yielding varieties on offer to the farmer. Thus during the period of adjustment to home-grown wheat after 1973, the milling industry had to select from a wide range of varieties of different milling and baking qualities. Selection was aided by the offer of a ‘premium’ (extra payment) for wheat of the right variety. The millers’ problem then was to be able to check that the wheat received was of the variety claimed by the supplier. Investigations of the heterogeneity ofgliadins by electrophoresis had been conducted by several workers, but a refined procedure was developed that used starch gel electrophoresis that was able to distinguish most varieties of wheat grown in France and the E.E.C. Different electrophoretic patterns were obtained from individual grains of different varieties: grains of the same variety gave similar patterns irrespective of growth environment. Subsequent developments of variety identification by electrophoresis have improved the resolution and time of analysis. Use of electrophoresis to check the varietal composition of grain being supplied to a British miller revealed that contracts that specified varietal content were usually, but not always, complied with. It was found that the miller was able to seek financial reimbursement from his supplier to compensate for the poorer grade of wheat received in about one in eight deliveries from France; and in about one in seven deliveries from the British farmer. Farmers have now adjusted to growing, storing and supplying varieties separately, such that the current frequency of erroneous grain delivery is about one in 50. The impact of variety identification by electrophoresis in barley trading has been less than in wheat trading. This is partly because it is sometimes possible to verify a purchase through examination of grain morphology, and partly because the alternative electrophoretic analysis is often impractical, because of frequently large numbers of barley varieties carrying identical hordein proteins.

Personification of the selection of pharmacological treatment of stress and post-stress disorders based on biometric data

2021 ◽  
Vol 19 (1) ◽  
pp. 123-126
Author(s):  
Raisa Ya. Tataritntseva ◽  
Lilia G. Ivanova ◽  
Dmitriy V. Migachev
Keyword(s):  
Remote Monitoring ◽  
Stress Disorders ◽  
Biometric Data ◽  
Mobile Medicine ◽  
Wide Range ◽  
Remote Treatment ◽  
Somatic Diseases ◽  
The Impact ◽  
Post Stress ◽  
Selection Of

Scientific researches have proven the pathogenetic relationship between stress and the development of a wide range of diseases. The impact of stress to the development of somatic diseases is well known, but greatly underestimated, since the treatment of stress and the correction of its consequences is an important aspect in the prevention and treatment of any, even infectious diseases, which was proved during the COVID-19 pandemic in 2020. The introduction of individual mobile medicine devices (M-Health) into a wide medical practice makes it possible to provide not only remote monitoring of the patients condition, but also to conduct remote treatment, with the selection and correction of drug therapy based on objective biometric data.

Onset Times and Detection of Colored Signal Lights

2005 ◽  
Vol 1918 (1) ◽  
pp. 123-127
Author(s):  
John D. Bullough
Keyword(s):  
Visual Detection ◽  
Practical Significance ◽  
Light Sources ◽  
Significant Potential ◽  
Color Characteristics ◽  
Signal Light ◽  
Wide Range ◽  
The Impact ◽  
Transportation Applications ◽  
Selection Of

Light sources used in signal lights for transportation applications have a variety of temporal onset characteristics, including a wide range of onset times. These characteristics, along with luminous intensity and color characteristics, can have important impacts on the ability to detect and respond to colored signal lights. Studies of the impact of these factors on responses to colored signals are reviewed, along with potential implications for the selection of light sources used in traffic and vehicle signals. The onset characteristics of recently developed light sources might offer significant potential to improve visual detection of signal lights. Nonetheless, it is important to understand the context in which a signal light is presented to determine whether such improvements in visual detection have practical significance.

The Identification of Language Impairment in the Selection of Specifically Language-Impaired Subjects

1990 ◽  
Vol 55 (3) ◽  
pp. 468-475 ◽  
Author(s):  
Rebecca J. McCauley ◽  
M. J. Demetras
Keyword(s):  
Language Impairment ◽  
Receptive Language ◽  
Research Literature ◽  
Language Impaired ◽  
Wide Range ◽  
Test Use ◽  
The Impact ◽  
Specific Number ◽  
Source Of Information ◽  
Selection Of

This review focused on the methods used to identify language impairment in specifically language-impaired subjects participating in 72 research studies that were described in four journals from 1983 to 1988. The single most frequent source of information used in the identification process was found to be test data. There was, however, considerable variability and, often, a lack of clarity regarding the specific number and identity of tests used. More specific findings on test use indicated that researchers routinely assessed both expressive and receptive language and that they used incomplete tests. When test scores used in identification and selection were examined, there was a wide range of score types, and age-equivalent scores were by far the most common and often the only type of score utilized. Conclusions are drawn regarding the impact of these findings on the interpretation and generalizability of this research literature.

Study on Dynamic Behavior of a Gas Pressure Relief Valve for a Big Flow Rate

2013 ◽  
Author(s):  
Victor Sverbilov ◽  
Dmitry Stadnick ◽  
Georgy Makaryants
Keyword(s):  
Flow Rate ◽  
Gas Flow ◽  
Dynamic Properties ◽  
Gas Pressure ◽  
Pressure Relief Valve ◽  
Relief Valve ◽  
Pressure Relief ◽  
Wide Range ◽  
The Impact ◽  
Pilot Valve

The paper investigates instable behavior of a poppet-type gas pressure relief valve operating at a big flow rate (more than 2 kg/s) under super critical pressure drop. Instability is experienced as noise and vibration and leads to severe damage of a seat and other elements. Significant and unsteady flow forces coupled with small inherent damping make it difficult to stabilize the system. In previous works, the analytical and experimental research was carried out to reveal the most essential factors influencing stability and dynamic properties of the valve. The impact of the pilot valve dynamics on the system behavior was studied for the purpose of obtaining required accuracy and stability in a wide range of flow rate. It was shown in some testing that unstable behavior of the main valve occurred when the pilot valve was stable. This paper considers inherent stability of the main valve in the gas flow. CFD software ANSYS FLUENT is employed to study the effect of the poppet geometry on aerodynamic lifting force and valve stability in axial and lateral direction. The results have been verified through comparison with experimental data.

scholarly journals Effect of Aftershock Characteristics on the Fragility Curve of Post-Mainshock RC Frames

2021 ◽  
Author(s):  
Ali Massumi ◽  
Kabir Sadeghi ◽  
Omid Ghojoghi
Keyword(s):  
Fragility Curves ◽  
Significant Duration ◽  
Rc Frames ◽  
Collapse Probability ◽  
Site Characteristics ◽  
Wide Range ◽  
Seismic Records ◽  
Earthquake Sequences ◽  
The Impact ◽  
Selection Of

Abstract Buildings constructed in seismic zones are not only damaged by mainshocks but may also be damaged by the impact of aftershocks and cause them to collapse. Therefore, studying the behavior of the damaged structures due to the mainshock and aftershock helps in post-mainshock decision making and also in the selection of suitable aftershock records for seismic assessing of the structure under earthquake sequences. This paper presents the effects of aftershock ground motion on the collapse capacity of post-mainshock buildings. The mean period (Tm), predominant velocity period (Tg), frequency bandwidth (Ω), the 5%-95% significant duration (Ds) and seismic records of different sites were selected to evaluate the effect of its characteristics on the collapse capacity of buildings. The intensity of the ground motions was determined by the first-mode spectral acceleration with 5% damping. Collapse capacities of two non-ductile reinforced concrete (RC) frames with 3 and 6 stories were evaluated using a set of 62 aftershock records with a wide range of characteristics. Box plot collapse diagrams and fragility curves have been developed by applying the incremental dynamic analysis (IDA). The results show that in the frequency content with a longer period, the probability of its collapse is higher. In addition, the high significant duration of aftershocks increases the collapse probability of structures. Also, the evaluation of the site characteristics shows differences in collapse capacities of the same frames in varying sites. Therefore, the effect of aftershock characteristics on the capacity of the structures is significant and it is necessary to carefully determine the seismic sequences’ recordings for the evaluation of the seismic behavior of the structures.

scholarly journals Toward a syntactic phylogeny of modern Indo-European languages

2013 ◽  
Vol 3 (1) ◽  
pp. 122-152 ◽  
Author(s):  
Giuseppe Longobardi ◽  
Cristina Guardiano ◽  
Giuseppina Silvestri ◽  
Alessio Boattini ◽  
Andrea Ceolin
Keyword(s):  
Long Range ◽  
Horizontal Transmission ◽  
Comparison Method ◽  
Interference Effects ◽  
Historical Reconstruction ◽  
Objective Measurements ◽  
European Languages ◽  
Wide Range ◽  
The Impact ◽  
Selection Of

The Parametric Comparison Method (PCM, Guardiano & Longobardi 2005, Longobardi & Guardiano 2009) is grounded on the assumption that syntactic parameters are more appropriate than other traits for use as comparanda for historical reconstruction, because they are able to provide unambiguous correspondences and objective measurements, thus guaranteeing wide-range applicability and quantitative exactness. This article discusses a set of experiments explicitly designed to evaluate the impact of parametric syntax in representing historical relatedness, and performed on a selection of 26 contemporary Indo-European varieties. The results show that PCM is in fact able to correctly identify genealogical relations even from modern languages only, performing as accurately as lexical methods, and that its effectiveness is not limited by interference effects such as ‘horizontal’ transmission. PCM is thus validated as a powerful tool for the analysis of historical relationships not only on a long-range perspective (as suggested by Longobardi & Guardiano 2009), but even on more focused, though independently well-known domains.

scholarly journals The Impact of Normalization Methods on RNA-Seq Data Analysis

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
J. Zyprych-Walczak ◽  
A. Szabelska ◽  
L. Handschuh ◽  
K. Górczak ◽  
K. Klamecka ◽  
...  
Keyword(s):  
High Throughput Sequencing ◽  
Data Sets ◽  
Complex Data ◽  
Rna Seq ◽  
Medical Problems ◽  
Data Set ◽  
Normalization Methods ◽  
Wide Range ◽  
The Impact ◽  
Selection Of

High-throughput sequencing technologies, such as the Illumina Hi-seq, are powerful new tools for investigating a wide range of biological and medical problems. Massive and complex data sets produced by the sequencers create a need for development of statistical and computational methods that can tackle the analysis and management of data. The data normalization is one of the most crucial steps of data processing and this process must be carefully considered as it has a profound effect on the results of the analysis. In this work, we focus on a comprehensive comparison of five normalization methods related to sequencing depth, widely used for transcriptome sequencing (RNA-seq) data, and their impact on the results of gene expression analysis. Based on this study, we suggest a universal workflow that can be applied for the selection of the optimal normalization procedure for any particular data set. The described workflow includes calculation of the bias and variance values for the control genes, sensitivity and specificity of the methods, and classification errors as well as generation of the diagnostic plots. Combining the above information facilitates the selection of the most appropriate normalization method for the studied data sets and determines which methods can be used interchangeably.

scholarly journals Structural Equation Model of Strategies for Successful Stakeholder Management in PPPs

10.29007/d4lr ◽  
2018 ◽  
Author(s):  
Sajani Jayasuriya ◽  
Guomin Zhang ◽  
Rebecca Yang
Keyword(s):  
Structural Equation ◽  
Structural Model ◽  
Project Success ◽  
Stakeholder Management ◽  
Decisive Role ◽  
Equation Model ◽  
Correct Selection ◽  
Clear Understanding ◽  
Equation Modelling ◽  
Selection Of

Public Private Partnerships (PPPs) have become an increasingly popular choice for the delivery of infrastructure facilities in the recent years. With the involvement of multiple numbers of stakeholders in a PPP project, stakeholder management (SM) plays a decisive role in project success. However, many issues in the recent PPP projects in Australia as well as around the world can be directly or indirectly related to the SM concerns of a project. The correct selection of SM strategies and a proper framework will help to solve most of the current SM related issues in PPP projects. In an attempt to understand these preemptive SM strategies and their links to SM management related issues in PPP projects, a hierarchical structural model was established. Subsequently, by employing the structural equation modelling technique, the model adapts a total of 34 SM strategies and 12 SM related issues. Based on the survey data collected across the industry experts who have exposure to a various number of PPP projects in Australia the results of the model confirmed that the stakeholder engagement is a key to minimize the SM related issues in the PPP projects. Further, interestingly stakeholder monitoring and SM related issues has a positive significant relationship suggesting that more the stakeholder monitoring might lead to more issues. Finally, the relationships between the main tasks of SM were confirmed via the model. With a clear understanding of the significance of these SM strategies in PPP projects the findings could potentially contribute to the PPP project success.

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