Modelling the clogging of coarse gravel and tire shreds in column tests

2007 ◽  
Vol 44 (11) ◽  
pp. 1273-1285 ◽  
Author(s):  
R. Kerry Rowe ◽  
Dan Babcock
Keyword(s):  
Laboratory Tests ◽  
Suspended Solids ◽  
Good Prediction ◽  
Column Tests ◽  
Average Grain Size ◽  
Tire Shreds ◽  
Different Types ◽  
Monod Kinetic ◽  
Coarse Gravel ◽  
Waste Leachate

A combination of data from laboratory tests and modelling is reported for both coarse gravel (19–38 mm) and two types of tire shred permeated with municipal solid waste leachate. It is suggested that the dispersivity of both the coarse gravel (initially about 4 mm) and tire shreds (initially about 45 mm) increases as the porosity of the drainage media is reduced because of clogging. The detachment of biofilm caused by growth and shear is examined and both are found to influence clogging. The average grain size estimated based on the measured surface area of the particles within a unit volume is shown to provide a good prediction of the rate of clogging for gravel and a conservative prediction for tire shreds. The size and density of suspended solids in leachate is found to significantly influence clogging rates. It is shown that Monod kinetic constants deduced for gravel at 27 °C give a good prediction of clogging for two different types of tire shred at the same temperature. Calibrated parameters used with the BioClog model are shown to give good fits to the porosity of both gravel and tire shred drainage material in laboratory column tests over time periods of up to 2 years.

scholarly journals Nomogram based on homogeneous and heterogeneous associated factors for predicting distant metastases in patients with colorectal cancer

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Tianwen Luo ◽  
Yutong Wang ◽  
Xuefeng Shan ◽  
Ye Bai ◽  
Chun Huang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Risk Factors ◽  
Lung Metastases ◽  
Roc Curves ◽  
Distant Metastases ◽  
Good Prediction ◽  
Operating Characteristics ◽  
Good Prediction Performance ◽  
Different Types ◽  
Associated Risk Factors

Abstract Background The identification of the homogeneous and heterogeneous risk factors for different types of metastases in colorectal cancer (CRC) may shed light on the aetiology and help individualize prophylactic treatment. The present study characterized the incidence differences and identified the homogeneous and heterogeneous risk factors associated with distant metastases in CRC. Methods CRC patients registered in the SEER database between 2010 and 2016 were included in this study. Logistic regression was used to analyse homogeneous and heterogeneous risk factors for the occurrence of different types of metastases. Nomograms were constructed to predict the risk for developing metastases, and the performance was quantitatively assessed using the receiver operating characteristics (ROC) curve and calibration curve. Results A total of 204,595 eligible CRC patients were included in our study, and 17.07% of them had distant metastases. The overall incidences of liver metastases, lung metastases, bone metastases, and brain metastases were 15.34%, 5.22%, 1.26%, and 0.29%, respectively. The incidence of distant metastases differed by age, gender, and the original CRC sites. Poorly differentiated grade, more lymphatic metastasis, higher carcinoembryonic antigen (CEA), and different metastatic organs were all positively associated with four patterns of metastases. In contrast, age, sex, race, insurance status, position, and T stage were heterogeneously associated with metastases. The calibration and ROC curves exhibited good performance for predicting distant metastases. Conclusions The incidence of distant metastases in CRC exhibited distinct differences, and the patients had homogeneous and heterogeneous associated risk factors. Although limited risk factors were included in the present study, the established nomogram showed good prediction performance.

scholarly journals The laboratory tests of hybrid layers combining hardfacing and nitriding dedicated to increase the durability of forging tools in hot forging processes

2019 ◽  
Vol 91 (2) ◽  
Author(s):  
Paweł Widomski ◽  
Zbigniew Gronostajski ◽  
Marcin Kaszuba ◽  
Jagoda Kowalska ◽  
Mariusz Pawełczyk
Keyword(s):  
Surface Layer ◽  
Chemical Composition ◽  
Laboratory Tests ◽  
Hot Forging ◽  
Composition Analysis ◽  
Wear Resistant ◽  
Gas Nitriding ◽  
Use Wear ◽  
Different Types ◽  
Hybrid Layers

In response to the growing need to use wear-resistant layers that increase durability of tools in forging pro-cesses, hybrid layers have been proposed that combine hardfacing with nitriding treatment. This article presents the results of laboratory tests of surface wear-resistant layers made with a new hybrid technology Gas-Shielded Metal Arc surfacing (hardfacing) with ZeroFlow gas nitriding. Specimens made with hardfacing or nitriding were prepared and examined. Analysis covered the thorough microstructure study, EDX chemical composition analysis and microhardness analysis. In experiment, 3 different types of nitrided layers were proposed for alpha, gamma prim and epsilon nitrides in the surface layer. The results of metallographic research in the surface layer was presented. The analysis of chemical composition in the particular overlay welds was performed to determine the content of alloying elements in the particular overlay welds. The susceptibility to nitriding of used weld materials as well as the ability to form particular types of nitrides on selected welded substrates was also tested.

scholarly journals Research on Horizontal Coefficient of Consolidation of Vietnam’s Soft Soil

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Nu Nguyen Thi ◽  
Bui Truong Son ◽  
Do Minh Ngoc
Keyword(s):  
Experimental Study ◽  
Laboratory Tests ◽  
Soft Soil ◽  
Coefficient Of Consolidation ◽  
Prefabricated Vertical Drains ◽  
Vertical Drains ◽  
Constant Rate ◽  
Different Types ◽  
Cell Test ◽  
Dissipation Test

The horizontal coefficient of consolidation is the most important parameter for designing the improvement of soil soft by prefabricated vertical drains (PVDs) combined with surcharge and vacuum preloading. This paper presents the experimental study on the horizontal coefficient of consolidation (ch) of some soft soils distributed in Vietnam. The ch value was determined by the laboratory test and CPTu dissipation test. The laboratory tests included the Rowe consolidation cell test and constant rate of strain consolidation with radial drainage test. Two types of consolidation laboratory tests were performed. The experimental results indicated that the ch value is always larger than the vertical coefficient of consolidation of soil (cv). The ratio of ch/cv depends on the consolidated pressure, type of soil, and the anisotropy of soil. The ratio of ch/cv is different in different types of soft soil in Vietnam. In the normally consolidated state, the ch/cv ratio ranges from 1.35 to 10.59. It was necessary to choose the ch value at the consolidated stress level for calculating the PVD spacing.

scholarly journals A brief compendium of water entry results derived from laboratory tests of various types of wall assemblies

2019 ◽  
Vol 282 ◽  
pp. 02050
Author(s):  
Michael A. Lacasse ◽  
Nathan Van Den Bossche ◽  
Stephanie Van Linden ◽  
Travis V. Moore
Keyword(s):  
Numerical Simulation ◽  
Performance Evaluation ◽  
Laboratory Tests ◽  
Moisture Transfer ◽  
Control Design ◽  
Water Entry ◽  
Building Envelope ◽  
Test Results ◽  
Different Types ◽  
Wood Frame

There is an increase in the use of hygrothermal models to complete the performance evaluation of walls assemblies, either in respect to design of new assembles or the retrofit of existing wall assemblies. To this end there are guides available in which is provided information on moisture loads to wall assemblies. This includes, for example, Criteria for Moisture-Control Design Analysis in Buildings given in ASHRAE 160, Assessment of moisture transfer by numerical simulation provided in EN 15026, and NRC’s “Guidelines for Design for Durability of the Building Envelope”. The designer of a new assembly or evaluator of an existing wall is tasked with having to determine what moisture loads to apply to the wall and where to apply this load within the assembly. Typically there is little or no information that is readily available regarding moisture loads to walls and thus the suggested hourly moisture load, as given in ASHRAE 160, is 1% by weight of the total driving rain load to the wall (i.e. kg/m2-hr). In this paper, a brief compendium of water entry test results derived from laboratory tests of various types of wall assemblies is provided from which estimates of moisture loads to different types of wall can be developed. Water entry test results are given of wood frame walls typically used in housing, but also metal-glass curtain walls and other commercial wall assemblies, where possible, in terms of driving loads to the wall.

Prediction of Association Among Factors in a Disease Using Machine Learning

2020 ◽  
Vol 17 (8) ◽  
pp. 3402-3407
Author(s):  
M. S. Roobini ◽  
V. Vaishali ◽  
T. Sangeethai ◽  
M. Lakshmi ◽  
Anitha Ponraj
Keyword(s):  
Laboratory Tests ◽  
Accurate Result ◽  
Great Accuracy ◽  
Great Care ◽  
Critical Factors ◽  
Medical Field ◽  
Human System ◽  
Svm Algorithm ◽  
Different Types ◽  
Neuro Imaging

Deep learning is being broadly used for various problems faced in medical field reports. There are various symptoms and early stimulation signs that leads to a dangerous effect in the human system. In today’s world, opinions and analysis accessible to us are one of the most critical factors in formulating our prediction and similarities and its treatment must be done with great care some tests such as habits, neuro psychological and laboratory tests, neuro imaging and electroencephalography (EEG) are taken prior the treatment. By the usage of SVM algorithm find similar symptoms these include with great accuracy. Various factors are taken into account and a thorough analysing is done with different types of classifier to find the most accurate one. SVM is a productive algorithm to be used but this paper mainly focuses on providing various analysing algorithm for acquiring accurate result.

The Value of Reclaimed Rubber in Tread Stock

1929 ◽  
Vol 2 (4) ◽  
pp. 517-524
Author(s):  
C. W. Sanderson
Keyword(s):  
Laboratory Tests ◽  
Relative Cost ◽  
The Road ◽  
Different Types

Abstract The road abrasion value has been determined on a series of tread stocks containing from 0 to 100 per cent. reclaim hydrocarbon. There is a close check between the road value as determined on two different types of road tests. The value of reclaim in this test is shown to vary from 25 to 42 per cent. of the value of new rubber, being higher for the all reclaim stock. The relative cost per unit of abrasion is shown to be above rubber at all points for 20-cent rubber. For 40-cent rubber it is lower than rubber when used above 50 per cent. reclaim hydrocarbon. The relative values for laboratory tests are compared to the road value. The tensible, lamination tear, and the 30 per cent. slip abrasion seem to give the best indication of road value.

scholarly journals Modulus of Elasticity and Compressive Strength of Tuff Masonry: Results of a Wide Set of Flat-Jack Tests

Buildings ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 84 ◽  
Author(s):  
Mariateresa Guadagnuolo ◽  
Marianna Aurilio ◽  
Andrea Basile ◽  
Giuseppe Faella
Keyword(s):  
Compressive Strength ◽  
Modulus Of Elasticity ◽  
Laboratory Tests ◽  
Seismic Analysis ◽  
Existing Buildings ◽  
Campania Region ◽  
Existing Structures ◽  
Wide Range ◽  
Different Types ◽  
The Mean

The assessment of the modulus of elasticity and compressive strength of masonry is a fundamental step in the seismic analysis of existing structures. In this paper, the representativeness of the values provided by flat-jack tests for tuff masonry is investigated through the analysis of a very large and homogeneous number of tests (635 double flat-jack tests). Data relate to existing buildings belonging to different historical and/or construction periods, located throughout the Campania region (Italy) in areas with different peculiarities. Results are compared with the values provided by Italian Building Code, containing ranges of the elastic modulus and compressive strength for different types of masonry. The values of flat-jack tests are then compared with laboratory tests available in the literature. Finally, comparisons with code equations are performed. It is shown that equations correlating the masonry compressive strength with the modulus of elasticity provide values larger than the mean of experimental data, whereas the equations correlating the masonry compressive strength with the strength of components provide lower values, if block and mortar strengths are varied within a probable and wide range.

scholarly journals Laboratory tests of Estonian landfill leachate

2019 ◽  
pp. 289-299
Author(s):  
Pille Kängsepp ◽  
William Hogland ◽  
Mait Kriipsalu ◽  
Toomas Timmusk
Keyword(s):  
Constructed Wetland ◽  
Landfill Leachate ◽  
Laboratory Tests ◽  
Nitrogen Compounds ◽  
Multiple Treatment ◽  
Different Types ◽  
Treatment Stage ◽  
Before And After ◽  
Purification Methods ◽  
Engineered Wetland

During the last decade, many laboratory, pilot and full-scale experiments have beenconducted to investigate the optimal low-tech purification methods for the treatment ofnumerous types of wastewaters. Constructed wetland is a low-tech treatment system, whichusually contains multiple treatment possibilities. Frequently, some kind of soil treatmentsystem is included as one treatment stage. Engineered wetland systems for purification ofwastewater and leachate are not yet widely spread in Estonia. The possibility to use peat asfilter media for treatment of leachate from Aardlapalu landfill (Tartu County, Estonia) hasbeen studied. The leachate was transported into the laboratory, aerated and percolated throughtwo different types of peat filters. The concentration of nitrogen compounds, COD and BODwas measured in the leachate before and after treatment. Hydrological consequences andchemical changes in the peat were investigated.

scholarly journals Detecting the Presence of Different Types of Oil in Seawater Using a Fluorometric Index

Sensors ◽  
2019 ◽  
Vol 19 (17) ◽  
pp. 3774 ◽  
Author(s):  
Emilia Baszanowska ◽  
Zbigniew Otremba
Keyword(s):  
Baltic Sea ◽  
Water Column ◽  
Laboratory Tests ◽  
Crude Oils ◽  
Real Situation ◽  
Excitation Emission Matrix ◽  
Significant Difference ◽  
Different Types ◽  
Seawater Samples ◽  
Water Ratio

This study analyzed the fluorometric laboratory tests for the detection of the presence of oil in seawater in cases corresponding to the real situation in the sea: when the point of seawater sampling is not in the same place as the appropriate sensor. The phenomenon of fluorescence exhibited by both natural and alien substances (oil) in the sea was used. The possibility of oil detection in the water column based on a fluorometric index (FI) extracted from the excitation–emission matrix (EEM) was studied. Laboratory tests were carried out on water taken from the Gulf of Gdańsk (Baltic Sea). Seawater samples were contaminated with small amounts of various types of oil (the lowest oil-to-water ratio was 0.5 × 10−6). A statistically significant difference was found between FI values for uncontaminated seawater and seawater exposed to various kinds of oil (i.e., crude oils, lubricant oils, and fuels).

Field and laboratory investigations of the clay tills at the test bed site at the Building Research Establishment, Garston, Hertfordshire

1991 ◽  
Vol 7 (1) ◽  
pp. 229-238 ◽  
Author(s):  
A. Marsland ◽  
J. J. M. Powell
Keyword(s):  
Soil Profile ◽  
Laboratory Tests ◽  
Research Station ◽  
Test Bed ◽  
Building Research ◽  
Soil Fabric ◽  
Different Types ◽  
Loading Tests ◽  
Laboratory Investigations ◽  
A Site

AbstractDetailed investigations have been made of the clay tills on a site located at the Building Research Station about 30km NW of central London. Inspection of the soil macrofabric suggests that two advances of the ice occurred in this area.Results from insitu tests using cone penetrometers, pressuremeters, 100mm diameter screw plate tests, 292 and 865 mm diameter deep insitu loading tests, and laboratory tests are given. The results obtained from different types of tests are compared against the background of the modes of deposition, post depositional conditions and the variations in the soil fabric down the soil profile.

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