scholarly journals Impact of the Winding Angle of the Auger Blade on the Loading Process With Milling Auger Drums

2020 ◽  
Vol 3 (1) ◽  
pp. 241-250
Author(s):  
Tomasz Wydro
Keyword(s):  
Milling Process ◽  
Design Parameters ◽  
Mining Machine ◽  
Loading Process ◽  
Auxiliary Process ◽  
Correct Determination ◽  
The Individual ◽  
The Impact ◽  
Winding Angle

AbstractThis publication addresses the impact of selected design parameters of milling auger cutting drums on the loading process, and above all the winding angle of the auger blade. The loading process is often referred to as an auxiliary process because the milling process is considered to be the dominant throughout the work of the cutting drum. The correct determination of the relationship between the mining process and the loading process allows to understand how the individual design and kinematic parameters of the mining drums and the mining machine on which they are installed affect each other. The publication discusses the problem of loading with milling cutting drums and ways to increase its efficiency. The research results of the loading process have been presented, affecting the efficiency of this process in the aspect of various angles of inclination of the auger blades. Based on the tests, conclusions have been formulated that allow for the possible selection of an appropriate winding angle for the auger blade, depending on the granulation of spoil.

scholarly journals Expressionism in European and Chinese painting (late XIX – early XXI centuries)

2020 ◽  
pp. 27-46
Author(s):  
Jitai Wang
Keyword(s):  
Comparative Analysis ◽  
Mutual Influence ◽  
Cultural Factors ◽  
Chinese Painting ◽  
Oil Painting ◽  
New Concepts ◽  
Similarities And Differences ◽  
The Individual ◽  
The Impact

This article examines the impact of Chinese traditional painting upon the formation of Western expressionism, as well as interprets the influence of Western expressionism upon Chinese painting in expressionist manner of different periods. The author reveals the mutual influence, similarities and differences between Western expressionism and Chinese painting in expressionist manner, Chinese imagery oil painting, Chinese colored ink painting, and Chinese imagery painting in Western style. Based on correlation between the spiritual ideology of painting and artistic form, the author carries out a comparative analysis of spiritual and formal factors of Chinese and Western painting systems for the purpose of determination of their mutual influence, and how it affects the emergence of new concepts in painting. The structure of brush stroke of the artist defines his aesthetic spirit. The article determines the “cyclic” nature of interinfluence processes between Chinese and Western painting systems that stimulate the development of human civilization. The analysis of corresponding cultural factors allows assessing the individual artistic characteristics of painting. Both, Chinese and Western painting systems entered the period when spiritual ideology of painting interacts with the artistic forms, opening the era of “globalization” of the language of painting.

Experimental analysis of cell pattern on grid fin aerodynamics in subsonic flow

2019 ◽  
Vol 234 (3) ◽  
pp. 537-562
Author(s):  
Manish Tripathi ◽  
Mahesh M Sucheendran ◽  
Ajay Misra
Keyword(s):  
Subsonic Flow ◽  
Lift Coefficient ◽  
Aerodynamic Performance ◽  
Aerodynamic Efficiency ◽  
Grid Fin ◽  
Stall Angle ◽  
The Individual ◽  
The Impact ◽  
Control Surfaces

Grid fins consisting of a lattice of high aspect ratio planar members encompassed by an outer frame are unconventional control surfaces used on numerous missiles and bombs due to their enhanced lifting characteristics at high angles of attack and across wider Mach number regimes. The current paper accomplishes and compares the effect of different grid fin patterns on subsonic flow aerodynamics of grid fins by virtue of the determination of their respective aerodynamic forces. Furthermore, this study deliberates the impact of gap variation on aerodynamics of different patterns. Results enunciate enhanced aerodynamic efficiency, and lift slope for web-fin cells and single diamond patterns compared to the baseline model. Moreover, the study indicates improved aerodynamic performance for diamond patterns with higher gaps by providing elevated maximum lift coefficient, delayed stall angle, and comparable drag at lower angles. The study established the presence of an additional effect termed as the inclination effect alongside the cascade effect leading to deviations with respect to lift, stall, and aerodynamic efficiency amongst different gap variants of the individual patterns. Thus, optimization based on the aerodynamic efficiency, stall angle requirements, and construction cost by optimum pattern and gap selection can be carried out through this analysis, which can lead to elevated aerodynamic performance for grid fins.

scholarly journals Critical Distance of the Seismic Waves’ Impact in Disintegration of Rock Blasting

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Dušan Kudelas ◽  
Blažej Pandula ◽  
Michal Cehlár ◽  
Marcela Taušová ◽  
Ján Koščo
Keyword(s):  
Critical Point ◽  
Seismic Waves ◽  
Critical Distance ◽  
Rock Blasting ◽  
Significant Difference ◽  
Explosive Charges ◽  
Speed Of Propagation ◽  
The Individual ◽  
The Impact

The presented paper deals with attenuation of seismic waves, which depends on the degree of disintegration of the rock environment in which seismic waves are propagated due to the explosion of explosive charges during blasting operations. Measurements of the impact of seismic waves were conducted to determine the best possible way to absorb these waves. The aim of the article is to identify the existence of a critical distance and the determination of the critical point from which the propagation of the velocity is not dependent on the type of deposit and the environment in which the seismic wave propagates. Statistical methods were used for these findings. The result is the determination of the distance of 80 m in which the speed on the individual deposits varied. From this limit on, there was no significant difference in the speed of propagation on the individual deposits.

Diagnosis of the Operation of Power Plants

2007 ◽  
Author(s):  
Jose´ Miguel Gonza´lez-Santalo´ ◽  
Abigail Gonza´lez-Di´az ◽  
Carlos Alberto Marin˜o-Lo´pez
Keyword(s):  
Power Plants ◽  
Environmental Changes ◽  
Environmental Parameters ◽  
Combined Cycle ◽  
Characteristic Parameters ◽  
Operating Variables ◽  
Design Values ◽  
The Individual ◽  
The Impact

A system was developed to diagnose the operation of combined cycle power plants and to determine, when deviations are found, which components are causing the deviations and the impact of each component deviation. The system works by comparing the values of the actual operating variables with some reference values that are calculated by a model that was adjusted to the design heat balances. The model can use the actual values of the environmental parameters as well as the design values, so the effect of environmental changes can be quantified and separated. The determination of the individual equipment impacts is done by adjusting the equipment parameters in order to reproduce the values of the measured variables. The adjustment is done by varying the values of the characteristic parameters of the equipment in order to minimize the sum of the squares of the differences between the values of the measured variables and the calculated values from the model.

scholarly journals Amplitude Modulated Noise for Tinnitus Suppression in Tonal and Noise-Like Tinnitus

2019 ◽  
Vol 24 (6) ◽  
pp. 309-321 ◽  
Author(s):  
Stefan Schoisswohl ◽  
Johannes Arnds ◽  
Martin Schecklmann ◽  
Berthold Langguth ◽  
Winfried Schlee ◽  
...  
Keyword(s):  
Past Research ◽  
Acoustic Stimulation ◽  
Short Term ◽  
Novel Approach ◽  
Different Types ◽  
Pure Tones ◽  
Residual Inhibition ◽  
The Individual ◽  
The Impact

Background: The phenomenon of short-term tinnitus suppression by different forms of acoustic stimulation is referred to as residual inhibition (RI). RI can be triggered in the majority of tinnitus cases and was found to be depending on the used intensity, length or types of sounds. Past research already stressed the impact of noise stimulation as well as the superiority of amplitude modulated (AM) pure tones at the individual tinnitus frequency for RI in tonal tinnitus. Recently a novel approach for the determination of noise-like tinnitus characteristics was proposed. Objectives: The aim of the present study was to investigate whether in participants with noise-like tinnitus RI can be increased by AM noise stimuli according to the individual tinnitus frequency range. Methods: For this purpose the individual tinnitus characteristics (noise-like and tonal tinnitus) of 29 people affected by tinnitus (mean age = 55.59, 7 females, mean tinnitus duration = 159.97 months) were assessed via customizable noise-band matching. The objective was to generate bandpass filtered stimuli according to the individual tinnitus sound (individualized bandpass filtered [IBP] sounds). Subsequently, various stimuli differing in bandpass filtering and AM were tested with respect to their potential to induce RI. Participants were acoustically stimulated with 7 different types of stimuli for 3 min each and had to rate the loudness of their tinnitus after each stimuli. Results: Results indicate a general efficacy of noise stimuli for the temporary suppression of tinnitus, but no significant differences between AM and unmodulated IBP. Significantly better effects were observed for the subgroup with noise-like tinnitus (n = 14), especially directly after stimulation offset. Conclusions: The study at hand provides further insights in potential mechanisms behind RI for different types of tinnitus. Beyond that, derived principles may qualify for new or extend current tinnitus sound therapies.

scholarly journals Impact of selected parameters on the loading process with cutting screw heads

2019 ◽  
Vol 2 (1) ◽  
pp. 249-256
Author(s):  
Tomasz Wydro
Keyword(s):  
Working Conditions ◽  
Cutting Process ◽  
Kinematic Parameters ◽  
Loading Process ◽  
Cutting Machine ◽  
Auxiliary Process ◽  
The Relationship

Abstract The article presents the influence of selected constructional and kinematic parameters of cutting screw heads on the loading process. The loading process is often referred to as an auxiliary process, because in the entire operation of the head the cutting process is considered dominant. Proper determination of the relationship between the cutting process and the loading process allows to understand how individual constructional and kinematic parameters of cutting heads and the cutting machine on which they are installed have an impact on each other. This knowledge gives potential users an opportunity to determine a reason for the lack of effective loading in the working conditions of a given wall. Besides construction and kinematic parameters, shielded loaders also have an impact on the loading process. The use of a shielded loader allows for improving the efficiency of the loading process, i.e. increasing the percentage of output loaded in the whole of the output transferred by the head.

Environmental Impacts of Lead Ore Mining and Smelting

2014 ◽  
Vol 878 ◽  
pp. 338-347 ◽  
Author(s):  
Narendra Singh ◽  
Jin Hui Li
Keyword(s):  
Health Effects ◽  
Anthropogenic Lead ◽  
Particulate Matter Emissions ◽  
Correct Determination ◽  
Lead Metal ◽  
Lead Levels ◽  
The Impact ◽  
Mining And Smelting ◽  
Lead Mining

Present day lead pollution is an environmental hazard of global proportions. A correct determination of natural lead levels is very important in order to evaluate anthropogenic lead contributions. In this paper, the impact of mining and smelting of lead metal ores on environmental quality is described. Globally mines produce large amounts of waste because the ore is only a small fraction of the total volume of the mined material. In the metal industry, production of lead, causes the greatest degradation of the environment. Lead smelters release large quantities of Cd and Pb into the environment as well as smelting and refining produce gaseous (CO2, SO2, NOx, etc.) and particulate matter emissions, sewage waters, and solid wastes; however, these pollutants take a lead to effects human health. A quantitative evaluation of the environmental health effects of lead mining and smelting is difficult because of the complexity of factors involved and lack of consistent methodology. Nevertheless, the investigation indicates that negative health effects could arise from lead mining and smelting.

scholarly journals PATHOGENETIC TREATMENT OF PATIENTS WITH HYPERTENSION, DEPENDING ON THE LEVEL OF SYMPATHОADRENAL SYSTEM ACTIVITY

2021 ◽  
Vol 48 (1) ◽  
Author(s):  
O. E. Alypova ◽  
V. O. Mochonyi ◽  
L. P. Kuznetsova ◽  
N. M. Protsenko ◽  
O. Y. Vasylchenko
Keyword(s):  
Nervous System ◽  
Sympathetic Nervous System ◽  
Arterial Hypertension ◽  
Healthy Subjects ◽  
Antihypertensive Treatment ◽  
Β Blocker ◽  
Sympathetic Nervous ◽  
The Individual ◽  
The Impact

Abstract Purpose of the study. Recently, new opportunities to optimize clinical efficacy and tolerability of treatment of patients with essential hypertension appeared. Determination of the indicators of increased activity of the sympathetic nervous system (SNS) in practice could contribute to differentiated treatment of patients with hypertension. Comparative estimation of influence of complex treatment with bisoprolol or amlodipine on the SNS activity parameters in patients with arterial hypertension (AH) of II stage. Materials and methods. 121 patients (men and women) with documented II stage AH were examined clinically. Concentrations of adrenaline, noradrenaline, dopamine and DOPA in urine were evaluated by spectrochromatography, endotheliumdependent vasodilation was studied using complex rheographic ReoCom Professional (HAI-Medicom, Ukraine). Patients were divided into 2 groups: if concentration of noradrenalin in urine exceeds healthy subjects levels more than on 20% – patients were added to basic treatment (enalapril, atorvastatin, aspirin) bisoprolol, if concentration of noradrenalin in urine exceeds healthy subjects levels less than on 20% – we added amlodipine. Statistic analysis was done on Apache OpenOffice (version 4.1) and PSPP (version 0.7.9). Results. The study showed that after treatment there was significant decrease of adrenalin, noradrenalin in 1st group . Increase of DOPA levels was higher in 1st group (Δ% = +46,5 [30,0; 55,4]% vs Δ% = +8,8 [–2,1 ; 16,0]%, (p < 0,05).). Trends in daily urinary excretion of adrenaline (–44,8%) and norepinephrine (–33,7%) showed the impact of effective Δ-blocker on the activity of pressor systems. DOPA excretion was increased significantly in both groups which can indirectly indicate hemodynamic load reduction in hypertensive patients. When choosing the individual antihypertensive treatment in patients with arterial hypertension, if excretion of noradrenalin is increased it is rationally to add adjuvant therapy with β-blockers. Conclusion. The results of our research can be applied into the practice of general practitioner as recommendations for individual selection of antihypertensive treatment depending on the activity of sympathetic nervous system. Keywords: arterial hypertension, treatment, sympathetic nervous system, β-blocker, calcium antagonists.

scholarly journals Investigating Greenland's glaciers

1990 ◽  
Vol 148 ◽  
pp. 46-51
Author(s):  
A Weidick
Keyword(s):  
Point Of View ◽  
Short Term ◽  
Glacier Fluctuations ◽  
Glacier Changes ◽  
Future Events ◽  
Global Sea Level ◽  
The Individual ◽  
The Impact

Investigations of Greenland's glaciers undertaken by GGU are primarily related to the exploitation of meltwater from the Inland lce and local glaciers in western Greenland, i.e. they are essentially related to glacier hydrology (Olesen & Braithwaite, 1989). The studies are therefore based on mass balance data combined with investigations of superglacial melt/refreezing and the determination of the internal mode of drainage. Related to this work is the documentation of short-term glacier changes at specific localities identified as being of special interest for hydropower from the point of view of glacier hazards, i.e. for example damage caused by tapping of ice dammed lakes or change of proglacial draining caused by change in the glacier's thickness and extent. Similar documentation of long-term glacier fluctuations provides a background for control and modelling of past glacier fluctuations. The procedures have a direct bearing on the calculation of scenarios for future events related to the individual localities or, in a regional sense, to the impact of changes in Greenland glaciers on global sea level (the 'greenhouse effect’).

scholarly journals Determination of Chlorophyll and Carotenoids Present in the Seeds of the Plant Family Apiaceae and the Impact on Seed Quality

2018 ◽  
Vol 66 (4) ◽  
pp. 859-869 ◽  
Author(s):  
Marie Grulichová ◽  
Peter Mendel ◽  
Václav Trojan ◽  
Tomáš Vyhnánek
Keyword(s):  
Seed Quality ◽  
Seedling Emergence ◽  
Quality Parameters ◽  
Standard Laboratory ◽  
Plant Family ◽  
Pigment Contents ◽  
The Individual ◽  
The Impact ◽  
Β Carotene

In this study, we assessed the content of chlorophyllaandb, β-carotene and lutein in seeds of carrot, celery, dill, parsley and parsnip commercial varieties by spectrophotometric method. It was determined that the content of chlorophyllawas higher than chlorophyllband both differed significantly between plant species and varieties. The highest amounts of chlorophylla, chlorophyllb, β-carotene and lutein were detected in parsley “Olomoucka dlouha”. The lowest amounts of chlorophylla, chlorophyllb, β-carotene and no lutein were detected in celery “Nuget”, however, very low amount of lutein was detected in the parsley cultivars “Atika” and “Orbis”. The content of β-carotene was higher than that of lutein in most varieties. The individual pigment contents were compared to seed quality parameters such as standard laboratory germination and seedling emergence. Negative correlation between energy of germination and pigments and positive correlation between seedling emergence and pigments in the parsnip and parsley varieties was observed. Determination the content of pigments and correlations observed the possibility to use spectrophotometry to evaluate the pigments present in the seeds as an indicator of seed quality.

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