Heave of Spillway Structures on Clay Shales

1963 ◽  
Vol 1 (1) ◽  
pp. 5-15 ◽  
Author(s):  
R Peterson ◽  
N Peters
Keyword(s):  
Laboratory Tests ◽  
Western Canada ◽  
Test Results ◽  
Paper Briefly ◽  
Clay Shale ◽  
Frost Action ◽  
Existing Structures ◽  
Clay Shales ◽  
Spillway Structures

Construction of spillways on clay shale in Western Canada has resulted in some serious heave problems. This paper briefly describes the clay shales of the area and gives typical laboratory swelling test results. It has not yet been possible to predict total heave and rate of heave from laboratory tests. Observational programs to check the performance of existing structures as well as special tests were undertaken to provide information required for design. Typical heave observations at spillways showing the effect of seepage, frost action, and hold-down piles are included.

Predicting abnormal laboratory blood test results in the intensive care unit using novel features based on information theory and historical conditional probability (Preprint)

2021 ◽  
Author(s):  
Camilo E. Valderrama ◽  
Daniel J. Niven ◽  
Henry T. Stelfox ◽  
Joon Lee
Keyword(s):  
Machine Learning ◽  
Intensive Care ◽  
Conditional Probability ◽  
Blood Test ◽  
Laboratory Tests ◽  
Conditional Entropy ◽  
Admission Diagnosis ◽  
Test Results ◽  
Abnormal Laboratory ◽  
Blood Tests

BACKGROUND Redundancy in laboratory blood tests is common in intensive care units (ICU), affecting patients' health and increasing healthcare expenses. Medical communities have made recommendations to order laboratory tests more judiciously. Wise selection can rely on modern data-driven approaches that have been shown to help identify redundant laboratory blood tests in ICUs. However, most of these works have been developed for highly selected clinical conditions such as gastrointestinal bleeding. Moreover, features based on conditional entropy and conditional probability distribution have not been used to inform the need for performing a new test. OBJECTIVE We aimed to address the limitations of previous works by adapting conditional entropy and conditional probability to extract features to predict abnormal laboratory blood test results. METHODS We used an ICU dataset collected across Alberta, Canada which included 55,689 ICU admissions from 48,672 patients with different diagnoses. We investigated conditional entropy and conditional probability-based features by comparing the performances of two machine learning approaches to predict normal and abnormal results for 18 blood laboratory tests. Approach 1 used patients' vitals, age, sex, admission diagnosis, and other laboratory blood test results as features. Approach 2 used the same features plus the new conditional entropy and conditional probability-based features. RESULTS Across the 18 blood laboratory tests, both Approach 1 and Approach 2 achieved a median F1-score, AUC, precision-recall AUC, and Gmean above 80%. We found that the inclusion of the new features statistically significantly improved the capacity to predict abnormal laboratory blood test results in between ten and fifteen laboratory blood tests depending on the machine learning model. CONCLUSIONS Our novel approach with promising prediction results can help reduce over-testing in ICUs, as well as risks for patients and healthcare systems. CLINICALTRIAL N/A

scholarly journals Utilisation of laboratory test results for patient management by clinicians at two large referral hospitals in Zambia

2020 ◽  
Author(s):  
Sabe Mwape ◽  
Victor Daka ◽  
Scott Matafwali ◽  
Kapambwe Mwape ◽  
Jay Sikalima ◽  
...  
Keyword(s):  
Teaching Hospital ◽  
Laboratory Tests ◽  
Patient Management ◽  
Medical Laboratory ◽  
Test Results ◽  
Cross Sectional ◽  
Childrens Hospital ◽  
Laboratory Test Results ◽  
Laboratory Results ◽  
Referral Hospitals

Background Medical laboratory diagnosis is a critical component of patient management in the healthcare setup. Despite the availability of laboratory tests, clinicians may not utilise them to make clinical decisions. We investigated utilsation of laboratory tests for patient management among clinicians at Ndola Teaching Hospital (NTH) and Arthur Davison Childrens Hospital (ADCH), two large referral hospitals in the Copperbelt Province, Ndola, Zambia. Method We conducted a descriptive cross-sectional study among clinicians. The study deployed self-administered questionnaires to evaluate clinician utilisation, querying and confidence in laboratory results. Additional data on demographics and possible laboratory improvements were also obtained. Data were entered in Microsoft excel and exported to SPSS version 16 for statistical analysis. Results Of the 80 clinicians interviewed, 96.2% (77) reported using laboratory tests and their results in patient management. 77.5% (62) of the clinicians indicated they always used laboratory results to influence their patient management decisions. Of the selected laboratory tests, clinicians were more confident in using haemoglobin test results (91.2%). There was no statistically significant association between the clinicians gender or qualification and use of test results in patient management. Conclusion Our findings show that despite the majority querying laboratory results, most of the clinicians use laboratory results for patient management. There is need for interactions between the laboratory and clinical area to assure clinician confidence in laboratory results. Key words: utilisation, clinicians, laboratory tests, Ndola Teaching Hospital, Arthur Davison Childrens Hospital

scholarly journals Estimation of the characteristic compressive strength value of concrete based on the current code recommendations

2013 ◽  
Vol 12 (3) ◽  
pp. 193-200
Author(s):  
Izabela Skrzypczak
Keyword(s):  
Compressive Strength ◽  
Statistical Method ◽  
Test Results ◽  
Empirical Relationships ◽  
Existing Structures ◽  
Characteristic Strength ◽  
Characteristic Values ◽  
Current Code

The use of cores is an integral part of the assessment of existing structures that are modernized, redesigned or have been damaged. Evaluation of the test results and the estimation of characteristic values of compressive strength can be performed according to the statistical method proposed by the Annex D of the PN-EN 1990 [1] standard, and  also according to the PN-EN 13791 [2]. The procedures recommended in these both documents are different which can lead to various assessments of the characteristic values. The author has been verified whether the empirical relationships, defined in PN-EN 13791 [2], lead to obtaining larger values of characteristic strength and, consequently, to  estimation at the unsafe region. The characteristic compressive strength was of determined in accordance with the recommendations of  the PN-EN 13791 code [2] and the PN-EN 1990 - Annex D [1].

Study of the effect of test parameters on the assessment of steel resistance to carbon dioxide corrosion

2021 ◽  
Vol 87 (12) ◽  
pp. 36-41
Author(s):  
A. S. Fedorov ◽  
E. L. Alekseeva ◽  
A. A. Alkhimenko ◽  
N. O. Shaposhnikov ◽  
M. A. Kovalev
Keyword(s):  
Carbon Dioxide ◽  
Laboratory Tests ◽  
Oil And Gas ◽  
Oil And Gas Industry ◽  
Sample Surface ◽  
Test Results ◽  
Carbon Dioxide Corrosion ◽  
Gas Industry ◽  
Test Parameters ◽  
Repeatability And Reproducibility

Carbon dioxide (CO2) corrosion is one of the most dangerous types of destruction of metal products in the oil and gas industry. The field steel pipelines and tubing run the highest risk. Laboratory tests are carried out to assess the resistance of steels to carbon dioxide corrosion. However, unified requirements for certain test parameters are currently absent in the regulatory documentation. We present the results of studying the effect of the parameters of laboratory tests on the assessment of the resistance of steels to CO2 corrosion. It is shown that change in the parameters of CO2 concentration, chemical composition of the water/brine system, the buffer properties and pH, the roughness of the sample surface, etc., even in the framework of the same laboratory technique, can lead in different test results. The main contribution to the repeatability and reproducibility of test results is made by the concentration of CO2, pH of the water/brine system, and surface roughness of the samples. The results obtained can be used in developing recommendations for the choice of test parameters to ensure a satisfactory convergence of the results gained in different laboratories, as well as in elaborating of a unified method for assessing the resistance of steels to carbon dioxide corrosion.

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.

Experimental Analysis on Bond Behavior of GFRCM Applied on Clay Brick Masonry

2017 ◽  
Vol 747 ◽  
pp. 542-549
Author(s):  
Marianovella Leone ◽  
Valeria Rizzo ◽  
Francesco Micelli ◽  
Maria Antonietta Aiello
Keyword(s):  
Mechanical Performance ◽  
Tensile Tests ◽  
Brick Masonry ◽  
Test Results ◽  
Clay Brick ◽  
Hydraulic Lime ◽  
Bond Behavior ◽  
Existing Structures ◽  
Strength Failure ◽  
Hydraulic Lime Mortar

External bonded reinforcements (EBR), made by fibrous meshes embedded in a cementitious/hydraulic lime mortar, are getting a great deal of attention, mostly for strengthening, retrofitting and repair existing structures. In this context, the interest versus the FRCM (Fiber Reinforced Cementitious Matrix) is growing. The mechanical performance of these mortar-based reinforcements is not well known at the date and it needs to be investigated in terms of bond and tensile strength, strain and stiffness, in relation to the type of both substrate and fibers. The present work reports the results of an experimental study, still in progress, on different pre-cured GFRP grids embedded in inorganic matrices and applied on clay brick masonry. First, the mechanical properties of both pre-cured GFRP grid and GFRCM reinforcements were obtained through tensile tests. Then, the experimental investigation on bond behavior was carried out by direct shear bond test. The test results were collected and processed to evaluate bond strength, failure mode, load-slip relationship.

Multivariate interpretation of laboratory tests used in monitoring patients

1990 ◽  
Vol 36 (5) ◽  
pp. 748-751 ◽  
Author(s):  
H B Slotnick ◽  
P Etzell
Keyword(s):  
Small Groups ◽  
False Positive ◽  
Laboratory Tests ◽  
False Negative ◽  
Test Results ◽  
Laboratory Findings ◽  
Bonferroni Inequality ◽  
The Impact

Abstract This study demonstrates an approach to the problem of minimizing false-negative and false-positive laboratory findings. In this approach, we consider the fact that results of laboratory tests are correlated, utilize within-person test results to interpret current results, and minimize the impact of multivariate conservatism by examining test results in small groups. The procedure requires panels of tests to be divided into related subpanels, testing each subpanel independently, and using the Bonferroni inequality to determine whether any of the observed values for a given subpanel is "out-of-range." The procedure is demonstrated, and its limitations are observed and discussed.

scholarly journals Analytical Model for Predicting the UCS from P-Wave Velocity, Density, and Porosity on Saturated Limestone

2019 ◽  
Vol 9 (23) ◽  
pp. 5265 ◽  
Author(s):  
González ◽  
Saldaña ◽  
Arzúa
Keyword(s):  
Wave Velocity ◽  
Predictive Models ◽  
Laboratory Tests ◽  
Ultrasonic Pulse ◽  
P Wave ◽  
Test Results ◽  
Regression Analyses ◽  
P Wave Velocity ◽  
Dry Conditions ◽  
Engineering Projects

Rock mechanics and rock engineering projects require determining, among other parameters, the uniaxial compressive strength (UCS) of rock. For such a purpose, it is not uncommon to perform ultrasonic pulse laboratory tests. Many researchers have found experimental relationships between strength and P-wave velocity, but these relationships are based mainly on dry conditions and without considering any other physical or chemical characteristics of the studied rock. Specifically, for limestone, there are 11 correlations reported in the literature, eight of which are simple and the remaining three are multiple, and, among the latter, only two of them consider the saturation. In order to evaluate the combined effect of P-wave velocity, density, and porosity on the UCS of saturated limestone, simple and multiple regression analyses were carried out on the test results of 13 saturated limestone specimens to determine the parameters of both previously mentioned predictive models. The results showed that density is not correlated with strength.

An Impact Cutting Test for Tire Tread Stocks

1936 ◽  
Vol 9 (3) ◽  
pp. 520-530
Author(s):  
J. H. Dillon
Keyword(s):  
Laboratory Tests ◽  
Testing Machine ◽  
Test Results ◽  
Road Test ◽  
Cutting Resistance ◽  
Cutting Test ◽  
Impact Device ◽  
Impact Cutting ◽  
The Impact

Abstract The impact cutting device described in this paper is recommended for testing the cutting resistance of tread stocks because of its simplicity and the accuracy with which its results agree with road test results. The fact that the device was designed on semi-quantitative theoretical grounds gives some additional confidence in its results. It is possible that other cutting devices, designed with no regard to theory whatsoever, might operate as well as the impact device. However, it is felt that, since most laboratory tests on rubber stocks are necessarily largely empirical, it is well to attempt to design a testing machine which will operate in the ranges of the variables found in service.

Achievements in High Specific-Speed Water Turbines

1934 ◽  
Vol 128 (1) ◽  
pp. 361-407
Author(s):  
A. A. Fulton
Keyword(s):  
Stainless Steel ◽  
Laboratory Tests ◽  
Steady Increase ◽  
Test Results ◽  
Suction Tube ◽  
Generating Sets ◽  
Laboratory Test Results ◽  
Water Turbine ◽  
Specific Speed ◽  
Water Turbines

The steady increase in the capacity of generating sets created a demand for the high specific-speed turbine which was met by several experimenters. “Specific speed” is the speed at which a turbine will run under unit head when developing unit power, and nowadays a “high specific-speed” water turbine denotes one having a runner of the propeller type and a specific speed between 100 and 230 r.p.m. Difficulties were encountered in the development of propeller turbines, especially in connexion with cavitation. Laboratory tests and the use of visual study methods have played an important part in the solution of these difficulties. The method of fixing suction head in conjunction with laboratory test results is explained, and a comparison is made between the various forms of suction tube in use. Much work has been done to overcome the effects of localized cavitation, and stainless steel has been found to be very effective, especially when runners are cast entirely of that material. A method of operation has been developed to dispense with the use of inlet sluice gates in large machines. Several methods in use for operating the movable runner blades are described. The introduction of the high specific-speed turbine has led to a large increase in the number of automatic stations. The great size attained by these turbines has entailed the construction of equally large generators, the development of which has had its own problems.

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