Innovative Testing Methods Research Articles

Droplet surface exposure measurement of a large splashing oil fume in the kitchen with a fluorescent 3D microscopic passive testing method

Cooking is a major source of indoor particulate matter, surpassing smoking. Large splashing oil fumes produced by water-oil interactions while cooking have received increasing attention for their common and significant hazards. However, the pollution of large splashing droplets is rather difficult to quantitatively measure with the current techniques. In this study, a fluorescent 3D microscopic passive testing method that is accurate and reliable for large spaces and broad-spectrum droplets is developed by combining fluorescence tracer, passive sampling, microscopic vision and droplet 3D reconstruction technologies. The measurement error for submicron droplets is approximately 22.6%. Because large droplet pollution is not unique to the kitchen, our innovative test method is worthy of reference in many fields, such as cleaning and painting workshops. We tested the surface exposure of a large splashing oil fume of 1–500 μm with this method. The results showed that the particle size of splashing oil droplets presents a bimodal distribution, which matches the two generation mechanisms that have been observed. The surface exposure mass concentration of all droplets of 1–500 μm on the surface at a distance of 0.75 m from the emission source edge is reduced to 3.6% of 0.25 m. Droplets (10–100 μm) are the main pollutants, which have continuous indirect hazards and require more attention.

NEW PHARMACEUTICAL DOSAGE FORMS USED IN THE TREATMENT OF BREAST CANCER. LIPOSOMES

In order to obtain antineoplastic compounds and innovative formulations, new technologies and testing methods are continuously being developed. Unfortunately, besides cancer cells, chemotherapy also affects normal cells. An option to avoid toxicity is represented by the targeted cancer treatment using novel pharmaceutical dosage forms.
 Liposomes represent a relatively new pharmaceutical dosage form, used for their many advantages. In this article, the methods of liposomal preparation are mentioned, along with the classification and the latest improvements involving this pharmaceutical form. The bioavailability of conventional liposomes is currently improved by developing photodynamic liposomes, pH or temperature sensitive liposomes and targeted liposomes.

A Novel Equivalent Construction Method Applying to Radar EMS Threshold Test Under Multi-Source Heterogeneous Electromagnetic Environment

The received signal of the electronic equipment often depends on its surrounding multidimensional dynamic electromagnetic environment (MDEE) featured with large airspace, high field strength and wide frequency band. This brings great challenges to predict the electromagnetic compatibility (EMC) of the electronic equipment dynamically. As an extension to the conventional equivalent construction (EC) process for the static single-source electromagnetic environment, based on the response of an antenna port, a novel EC method for the dynamical multi-source heterogeneous electromagnetic environment is proposed in this article. By applying this EC method to a radar system under a practical dynamic working scene, an innovative electromagnetic sensitivity threshold test method is carried out in the laboratory. The experimental results show that the theoretically predicted value is in good agreement with the measurement, where the error is less than 1dB. With the methods proposed in this article, the dynamic analysis and prediction of EMC in MDEE can be carried out with the consideration of the characteristics of the electronic equipment, so that the electromagnetic environment adaptability of the electronic equipment can be readily improved.

A fractional order viscoelastic-plastic creep model for coal sample considering initial damage accumulation

In deep coal and rock mass engineering, extensive initial damage problems caused by excavation and unloading are critical to the long-term deformation and stability of underground projects. An innovative initial damage coal sample test method was proposed, and coal samples with different initial damage were prepared by the MTS pressure tester's circular displacement cyclic loading and unloading control. The creep characteristics of coal samples with different initial damages were tested by the staged loading creep test method. With the increase of initial damage, the coal samples’ creep time became shorter, and the rate of accelerated creep damage increased sharply. The relationship between fractional viscosity coefficient and stress was introduced to describe the non-linear relationship of creep strain increase at each stage. The creep model in the acceleration phase was improved by establishing the relationship between the damage variable and the initial damage. Based on the fractional calculus theory, a viscoelastic-plastic model considering the initial damage of coal samples was established, and the fractional order model was verified. The coefficient of correlation between the experimental data and the creep model was higher than 0.95, indicating that the fractional creep model can better describe the creep characteristics of coal samples with initial damage.

Revisiting the composite action in axially loaded circular CFST columns through direct measurement of load components

The composite action in circular concrete-filled steel tube (CFST) columns under axial compression is one of the most fundamental problems in the research area of steel-concrete composite structures. However, it cannot be easily investigated through experiments as the load components of the steel tube and concrete infill cannot be measured in a conventional axial loading test. In this study, an innovative testing method was devised to directly measure the load components of circular CFST columns under axial compression. Six innovative specimens with varying concrete strength and diameter-to-thickness (D/t) ratio and their conventional counterparts were tested. Although some difference existed between the load-deformation responses of the innovative and corresponding conventional specimens, it was essentially insignificant. The development of hoop stresses in the steel tube tends to reduce the corresponding axial stresses, but this effect can be offset by the strain hardening of the steel tube. Strain hardening of the steel tube should be considered when evaluating the confinement effect at the ultimate load, especially for columns with low concrete strength and small D/t ratio. The average values of the coefficients related to the axial and hoop stresses of the steel tube at the ultimate load, computed using available tests results, are 0.92 and −0.14, respectively. The proposed axial load capacity formula with these two values can reasonably predict the ultimate loads of circular CFST columns under axial compression.

Real-World Utilization of Biomarker Testing for Patients with Advanced Non–Small Cell Lung Cancer in a Tertiary Referral Center and Referring Hospitals

The continued introduction of biomarkers and innovative testing methods makes already complex diagnosis in patients with stage IV non-small-cell lung cancer (NSCLC) even more complex. This study primarily analyzed variations in biomarker testing in clinical practice in patients referred to a comprehensive cancer center in the Netherlands. The secondary aim was to compare the cost of biomarker testing with the cost of whole-genome sequencing. The cohort included 102 stage IV NSCLC patients who received biomarker testing in 2017 or 2018 at the comprehensive cancer center. The complete biomarker testing history of the cohort was identified using linked data from the comprehensive cancer center and the nationwide network and registry of histopathology and cytopathology in the Netherlands. Unique biomarker-test combinations, costs, turnaround times, and test utilization were examined. The results indicate substantial variation in test utilization and sequences. The mean cost per patient of biomarker testing was 2259.92 ± 1217.10 USD, or 1881.23 ± 1013.15 EUR. Targeted gene panels were most frequently conducted, followed by IHC analysis for programmed cell death protein ligand 1. Typically, the most common biomarkers were assessed within the first tests, and emerging biomarkers were tested further down the test sequence. At the cost of current biomarker testing, replacing current testing with whole-genome sequencing would have led to cost-savings in only two patients (2%).

Experimental and numerical studies on rebound characteristics of non-spherical particles impacting on stainless-steel at high temperature

In this paper, innovative test methods including aerodynamic acceleration, PIV measurement, separate statistics of incidence and rebound information were used to systematically investigate the rebound characteristics of flaky oxide particles and angular quartz sand impacting stainless steel at high temperature. Through the statistical analysis of a large number of experimental results and the measurement of the microscopic erosion morphology of the target surface, combined with the numerical simulation of the gas-solid two-phase flow of the test section, the intrinsic relationship between the rebound behavior of the particles and their erosion behavior was systematically explored for the first time. Meanwhile, the effects of the incident parameters, particle size and accelerated airflow on the rebound characteristics of the particles were revealed. The results have important guiding significance for further understanding the physical properties of particle-wall interaction and predicting the particle erosion characteristics and erosion distribution of industrial equipment components.

Post-peak behaviour of rocks under cyclic loading using a double-criteria damage-controlled test method

Cyclic loading–induced hazards are severe instability problems concerning surface and underground geotechnical projects. Therefore, it is crucial to understand the rock failure mechanism under cyclic loading. An innovative double-criteria damage-controlled testing method was proposed in this study to capture the complete stress–strain response of porous limestone, especially the post-peak behaviour, under systematic cyclic loading. The proposed test method was successful in applying the pre-peak cyclic loading and then in controlling the self-sustaining failure of rock during the post-peak cyclic loading. The results showed that the strength of the rock specimens slightly increased with an increase in the fatigue life in the pre-peak region due to cyclic loading–induced hardening. Additionally, a combination of class I and class II behaviours was observed in the post-peak region during the cyclic loading tests; the class II behaviour was more dominant by the increase in fatigue life in the pre-peak region. Damage evolution was assessed based on several parameters, such as the elastic modulus, energy dissipation ratio, damage variable and crack damage threshold stress, both in the pre-peak and post-peak regions. It was found that when the cyclic loading stress is not close to the peak strength, due to a coupled mechanism of dilatant microcracking and grain crushing and pore filling, quasi-elastic behaviour dominates the cyclic loading history, causing more elastic strain energy to accumulate in the specimens.

Prediction of Compressive Strength of Concrete Using Double-Shear Testing Method

AbstractThis study presents a partially nondestructive testing (PDT) method, the innovative double-shear test method (DSTM), to improve the accuracy of concrete strength tests in situ and reduce st...

Editorial for Special Issue: Test and Evaluation Methods for Human-Machine Interfaces of Automated Vehicles

Today, OEMs and suppliers can rely on commonly agreed and standardized test and evaluation methods for in-vehicle human–machine interfaces (HMIs). These have traditionally focused on the context of manually driven vehicles and put the evaluation of minimizing distraction effects and enhancing usability at their core (e.g., AAM guidelines or NHTSA visual-manual distraction guidelines). However, advances in automated driving systems (ADS) have already begun to change the driver’s role from actively driving the vehicle to monitoring the driving situation and being ready to intervene in partially automated driving (SAE L2). Higher levels of vehicle automation will likely only require the driver to act as a fallback ready user in case of system limits and malfunctions (SAE L3) or could even act without any fallback within their operational design domain (SAE L4). During the same trip, different levels of automation might be available to the driver (e.g., L2 in urban environments, L3 on highways). These developments require new test and evaluation methods for ADS, as available test methods cannot be easily transferred and adapted. The shift towards higher levels of vehicle automation has also moved the discussion towards the interaction between automated and non-automated road users using exterior HMIs. This Special Issue includes theoretical papers a well as empirical studies that deal with these new challenges by proposing new and innovative test methods in the evaluation of ADS HMIs in different areas.

Assessment of Pile Capacity Using Bidirectional Static Load Test (BDSLT)

Bidirectional Static Load Test (BDSLT), an innovative load test method, two static load tests performed simultaneously in opposite directions, adopting sacrificial hydraulic cells was globally used in the deep foundation industry. This paper presents the results of value engineering and optimization of the foundation design for the proposed pile tests from the Dubai Creek Harbour Project on plot no. A004, Dubai, UAE. The main objective of this load test was to proof-load the test pile to its ultimate capacity using the BDSLT method. For this purpose, 4 × 900 tons of capacity hydraulic cell/jacks was utilized. Two test piles of 1500 mm diameter were used, namely PTP1 and PTP2. Five levels of Geokon USA model 4200 vibrating wire-type strain gauges comprising four units at each level were also installed on the test pile to measure strain at nominated locations, and from that, load and unit skin frictions were derived. Results indicate that the skin friction was increased from values reported before pile testing. Pile capacities were optimized using the skin friction values obtained from the load test results.

Experimental Study on Influence of Disc Number on Soil Failure State of Concrete Expanded-Plate Pile under Horizontal Force in Oceanographic Engineering

Qian, Y.; He, M., and Wang, R., 2020. Experimental study on influence of disc number on soil failure state of concrete expanded-plate pile under horizontal force in oceanographic engineering. In: Gong, D.; Zhang, M., and Liu, R. (eds.), Advances in Coastal Research: Engineering, Industry, Economy, and Sustainable Development. Journal of Coastal Research, Special Issue No. 106, pp. 660–663. Coconut Creek (Florida), ISSN 0749-0208.As a new type of variable section pile, concrete expansion piles have the advantages of high bearing capacity, strong overturning resistance, and flexible design position. However, the effects of disc parameters on failure state and bearing capacity need further study. In this study, taking disc number as the main parameter, an innovative semisection pile model test method of undisturbed soil is proposed to study the influence of disc number on horizontal bearing capacity and soil failure state of concrete expanded piles under horizontal force. The research results of this study have further improved the test method, test device, and theoretical research conclusion of the undisturbed soil half-section model, which promotes popularization and application of concrete expansion piles.

Experimental research on torsional strength of synthetic/steel fiber-reinforced hollow concrete beam

Past research has used synthetic fiber (SY.F) and steel fiber (ST.F) for decades to advance concrete mechanical characteristics, including shear, tensile, and flexural strengths. Nevertheless, there is limited information concerning the torsional concrete reinforced with SY.F and ST.F performance. This research aims to explore the torsional performance of hollow reinforcement concrete beams reinforced with various fiber types. The fiber content of 1% with three different lengths of SY.F, 19, 38, and 57 mm, along with 13 mm of ST.F, was used. Two specimens were cast with normal concrete without using fibers as control beams and four hollow beams with ST.F and SY.F. To use a pure torsional load on the tested samples, an innovative test method was employed. The twisting angle of tested beams was calculated at each interval of the load as well as the first crack load and failure load. Outcomes illustrated that the utilizing of SY.F and ST.F in the reinforced concrete beams (RCB) enhanced the overall performance under torsional load compared to the control beam behaviors. This enhancement in the performance was relative to the fiber type and length. For the first cracking load, the tested beams reinforced with the ST.F and SY.F of 19 and 37 mm lengths showed approximately the same value. Also, the beam reinforced with the SY.F length of 55 mm exhibited the highest first cracking load value, among other tested beams. As the fiber length increases of SY.F, the ultimate load capacity was raised by 4.7, 9.4, and 21.9% for beams cast with 19, 37, and 55 mm fiber length, respectively. For the ST.F reinforcement concrete beam, the ultimate load capacity was raised by 5.5%. Therefore, due to the significant impact of SY.F on the torsional performance, it is recommended using SY.F with normal concrete.

An Innovative Test Method for Tensile Strength of Concrete by Applying the Strut-and-Tie Methodology.

Tensile strength is one of the important mechanical properties of concrete, but it is difficult to measure accurately due to the brittle nature of concrete in tension. The three widely used test methods for measuring the tensile strength of concrete each have their shortcomings: the direct tension test equipment is not easy to set up, particularly for alignment, and there are no standard test specifications; the tensile strengths obtained from the test method of splitting tensile strength (American Society for Testing and Materials, ASTM C496) and that of flexural strength of concrete (ASTM C78) are significantly different from the actual tensile strength owing to mechanisms of methodologies and test setup. The objective of this research is to develop a new concrete tensile strength test method that is easy to conduct and the result is close to the direct tension strength. By applying the strut-and-tie concept and modifying the experimental design of the ASTM C78, a new concrete tensile strength test method is proposed. The test results show that the concrete tensile strength obtained by this proposed method is close to the value obtained from the direct tension test for concrete with compressive strengths from 25 to 55 MPa. It shows that this innovative test method, which is precise and easy to conduct, can be an effective alternative for tensile strength of concrete.

Coronavirus diseases 2019 (COVID-19) response: Highlights of Ghana's scientific and technological innovativeness and breakthroughs

While more attention has been placed on scientific innovativeness and breakthroughs in the advanced countries’ attempt to contain the spread and develop vaccines for the Coronavirus Diseases 2019 (COVID-19), little attention has been paid to the few but significant innovations being achieved in some African countries. This is understandable because the scientific capacity and research infrastructure of most African countries are deficient and weak compared to other regions of the world. Nevertheless, the African country of Ghana, despite its acute healthcare and scientific infrastructure deficit, is achieving some innovational and scientific breakthrough in the COVID-19 fight. Ghanaian scientist was among the first in Africa to successfully sequenced the genome of the novel coronavirus (SARS-CoV-2). The country's laboratory leading the fight has also introduced some innovative testing methods allowing the country to test a far greater scale per million than the rest of Africa. Besides, drones are being used to deliver samples to the laboratory centers for testing. Local scientists and developers have also developed rapid diagnostic test kits, ventilators, and solar-powered handwashing machines. This paper highlights Ghana's innovativeness, scientific, and technological breakthroughs achieved so far in the fight against the pandemic.

Lack of tightness analysis of concealed welded radiators

Stainless steel X2CrNi18-9 (304L) radiators were analysed. During detailed examination we proved that tube overlap fillet joint was welded incorrectly and had leaks. Wrong designed jig, incorrect robot movements and non-central tubes position let mounted parts move during welding operation. Shrinkage of the weld caused the tubes to move relative to each other with the formation of a larger gap on one side. Lack of correction of the robot arm movement and fixed stick-out created inadequate fusion into the tube with a smaller cross-section.Identification of non-compliance based on standard NDT methods such as visual inspection, liquid or dye penetrant inspection or X-ray was not possible. Also, destructive methods such as high-pressure water test was not be able to show this type of defect.Only innovative HLT helium leak testing method was able to show non-compliance of the joint. Helium is the ideal element to detect micro cracks in weld as it is an insert gas made up to tiny atoms and has low viscosity, so little atoms can travel fast. This method has a very big potential in the welding industry as a precise and fast NDT test on highest quality requirements.

An Innovative Test Method for Multi-Chamber High Voltage Circuit Breakers

High voltage circuit breakers are often designed using multiple interrupting chambers connected in series for each pole/phase. These breakers need to undergo type tests and development tests. Especially for very high voltages, no test facilities may exist to perform a short circuit test on a complete breaker. Therefore, the possibility exists for testing only a part of the circuit breaker, termed as “unit testing”. For unit testing, different approaches can be adopted which include only a part of the circuit breaker. Especially for metal enclosed switchgear like Gas Insulated Switchgear (GIS) or a Dead Tank Breaker (DTB), unit testing has required a lot of additional effort and sometimes even a design change of the circuit breaker. In view of the above, a new innovative test method is proposed which uses a Metal Oxide Varistor (MOV) to bridge one unit/interrupting chamber of the test device. This method not only provides ease of testing but also gives sufficient feasibility for proof of dielectric withstand capability in relation to short circuit interruption. The presented method reduces the effort for necessary design changes to a minimum compared to other methods used. The proposed method has been validated by means of simulation and testing.

Thick slab punching with symmetry reductions

AbstractThe contribution presents a test series of four geometrically similar specimens of different size designed to investigate the punching behavior of thick reinforced concrete slabs. The thickness ranges from 300 to 650 mm and the slab radius varies between 1.12 and 2.45 m. For experimental execution, an innovative test method is employed and updated towards thick slabs. It uses the symmetry of specimens and reduces them corresponding to the symmetry grade to quarters. By applying this method, geometrical dimensions and associated test loads are reduced by 75%. The tests demonstrate on the one hand that the updated method is suitable for punching tests of thick specimens. And, on the other hand, the results indicate a less pronounced size effect for multilayered, highly reinforced slabs than predicted in theory.

Induction brazing of cermets to steel and eddy current testing of joint quality

The principal aim of the study was to demonstrate the feasibility of induction brazing of TiC-based cermets with Fe- and Ni-alloy binders under ambient atmosphere. A secondary aim was to investigate the possibility of using an innovative rapid non-destructive contactless testing method based on eddy current measurement for the evaluation of joint quality. Ag- and Cu-based filler metals and suitable fluxes developed for brazing of cemented carbides (WC-Co) to steels were employed. Results of the microstructure study and testing of shear strength enabled us to conclude that TiC-based cermets (TiC-FeCr and TiC-NiMo) can be successfully brazed under ambient atmosphere using filler metals and fluxes developed for WC-based cemented carbides. The shear strength of joints over 200 MPa can be achieved. Under similar brazing conditions, TiC-FeCr/steel joints compare favourably with TiC-NiMo/steel joints in terms of shear strength. The shear strength of TiC cermet/steel joints brazed with silver-based filler metal (Ag449) slightly increases (~13%) after prolonged heating at elevated temperature (250 °C). It was found that eddy current testing is prospective for rapid assessment of brazed joints quality with identical dimensions and chemical composition of multilayer structures. The differentiation of measurement results is the best at frequencies in the range of 10 … 100 kHz.

Innovative and Simple PV Generator Procedure to Test PV Inverter According to EN50530 Standard Static MPPT Efficiency

This paper details the different steps of an innovative and simple PV generator emulator (PVE) test method used to emulate the PV generator behavior required to carry out EN50530 European standard static MPPT efficiency test for a given PV inverter (PVI). The developed test procedure accurately determines the PVE control parameters using data selected from the datasheet of the PV inverter which is the Equipment Under Test (EUT) and basing on the EN50530 standard requirements. A software implemented under LabVIEW environment allows one to automatically compute the required test parameters, to communicate them to a STM32F4 target in order to accurately control the PVE for a given test scenario and to display the emulated I-V and P-V characteristics. Simulations carried out under the PSIM software demonstrate the accuracy of the suggested test procedure to fulfill the EN50530 requirements. Furthermore, experimental tests, carried out for the case study of a real-world 1100 W PVI, validate the effectiveness of the developed test procedure, and facilitate a new approach to the EN50530 MPPT efficiency test goals.