Search

Trends in the use of renewable energy sources to power buildings do not bypass objects for which maintaining a power supply is critical. This also applies to railway signal boxes. The aim of the research work was to test the multisource power supply system for a railway signal box with power electronic converter systems and a DC bus, built as part of the research project. The assumption for powering the railway signal box building was to use renewable sources, energy storage devices, and a 3 kV DC traction network as the second required power supply grid. Both power grids were connected by power electronic converters, and the power values of the converters were set based on the calculated power balance values using the values measured at the system nodes and the set constraints. The tests primarily tested the response of the power supply system to changes in load power and power generated by the photovoltaic source, as well as the charge level of the energy storage devices. The correctness of the control algorithm's operation was assessed based on the recorded power values in the power supply system nodes. The tests were carried out for 60 scenarios that covered all normal and emergency operating conditions. During the tests, delays in response to changes in the power supplied to the converters and the values of circular power flow between the power grid connections were recorded. The recorded delays ranged from 2 to about 50 s and the circular power flows did not exceed 1500 W. Based on the results of the tests, it was found necessary to improve the power measurement system in the power supply system nodes and to improve the quality of communication and the transmission time of measurement data transmission time. [ABSTRACT FROM AUTHOR]

Introduction: Sports Global Navigation Satellite Systems' receivers have been providing athletes, coaches, and scientists with valuable information on movement for over two decades. As these receivers are specific measuring instruments, there is a need to determine their accuracy. This paper presents a relatively simple methodology for assessing sports receivers of this type regarding their elevation determination. Material and methods: The methodology was based on the Digital Terrain Model of Poland, a discrete representation of the topographic elevation of the land surface. Three wearable devices from different years of manufacture were selected for the preliminary study by calculating the Root Mean Square (RMS), mean elevation error, and Total Elevation Gain (TEG) measures. The testing was conducted on two sections of varying length and elevation differences. Results: During the first trial, an instrument from 2019 came closest to the actual elevation (RMS = 7.0 m; mean error = -6.5 m), while during the second trial, it was an instrument from 2014 (2.5, -1.6 m, respectively). All the receivers overestimated the TEG factor during both trials. Conclusions: The applied methodology allowed the receivers to be distinguished. Due to the preliminary, pilot nature of the study, it is subject to certain limitations and recommendations listed at the end of the article. [ABSTRACT FROM AUTHOR]

Introduction: Sports Global Navigation Satellite Systems’ receivers have been providing athletes, coaches, and scientists with valuable information on movement for over two decades. As these receivers are specific measuring instruments, there is a need to determine their accuracy. This paper presents a relatively simple methodology for assessing sports receivers of this type regarding their elevation determination. Material and methods: The methodology was based on the Digital Terrain Model of Poland, a discrete representation of the topographic elevation of the land surface. Three wearable devices from different years of manufacture were selected for the preliminary study by calculating the Root Mean Square (RMS), mean elevation error, and Total Elevation Gain (TEG) measures. The testing was conducted on two sections of varying length and elevation differences. Results: During the first trial, an instrument from 2019 came closest to the actual elevation (RMS = 7.0 m; mean error = -6.5 m), while during the second trial, it was an instrument from 2014 (2.5, -1.6 m, respectively). All the receivers overestimated the TEG factor during both trials. Conclusions: The applied methodology allowed the receivers to be distinguished. Due to the preliminary, pilot nature of the study, it is subject to certain limitations and recommendations listed at the end of the article.

Trends in the use of renewable energy sources to power buildings do not bypass objects for which maintaining a power supply is critical. This also applies to railway signal boxes. The aim of the research work was to test the multisource power supply system for a railway signal box with power electronic converter systems and a DC bus, built as part of the research project. The assumption for powering the railway signal box building was to use renewable sources, energy storage devices, and a 3 kV DC traction network as the second required power supply grid. Both power grids were connected by power electronic converters, and the power values of the converters were set based on the calculated power balance values using the values measured at the system nodes and the set constraints. The tests primarily tested the response of the power supply system to changes in load power and power generated by the photovoltaic source, as well as the charge level of the energy storage devices. The correctness of the control algorithm’s operation was assessed based on the recorded power values in the power supply system nodes. The tests were carried out for 60 scenarios that covered all normal and emergency operating conditions. During the tests, delays in response to changes in the power supplied to the converters and the values of circular power flow between the power grid connections were recorded. The recorded delays ranged from 2 to about 50 s and the circular power flows did not exceed 1500 W. Based on the results of the tests, it was found necessary to improve the power measurement system in the power supply system nodes and to improve the quality of communication and the transmission time of measurement data transmission time.

Introduction. The ease of searching and copying someone elseʼs text on almost any topic is one of the most important reasons for the prevalence of plagiarism in academic papers. While plagiarism detectors have become a common tool for universities, such systems are practically not used in secondary schools. It is considered to be a serious problem, that high school graduates are unprepared for the academic papers’ originality requirements. Universities are making efforts to overcome this lack of readiness. The authors study the attitude of teachers and learners of the Russian secondary schools toward the problem of plagiarism. Materials and Methods. An anonymous online survey of teachers (n = 2,286) and learners (m = 4,555) of secondary schools in the Vologda, Kaliningrad and Lipetsk regions of the Russian Federation was conducted. The survey was carried out through the Google Forms service. The quantitative and qualitative analysis of the obtained data was carried out. Results. Learners acquire the habit of plagiarism already in secondary school. Secondary school learners are loyal to copying someone elseʼs text without reference to the source; although they partially admit that by doing so they do wrong. Teachers are less tolerant to this and ready to respond to plagiarism in learners’ papers by lowering marks/grades or by requiring learners to redo the work. Teachers do not always clearly understand which borrowings can be considered legitimate and correct, and which ones are not, they cannot explain this to their learners, cannot instill in them the necessary academic integrity, and cannot establish clear criteria for works evaluation.The use of plagiarism detection systems in schools is unsystematic and it is often the result of the initiative of individual teachers. There is also no methodology for using plagiarism detection systems in secondary schools. Discussion and Conclusion. The conducted studies for the first time provided actual confirmation of the hypotheses. It means that it is necessary to include plagiarism detection systems in the toolkit used in secondary school. We have obtained evidence, that it is necessary to implement such tools in the secondary education system step by step, as well as to create conditions, so that school teachers can acquire relevant skills. The materials of the article will be useful to scientists who study the problems of secondary and high education, managers of the secondary education system at all levels, teachers, lecturers and learners of pedagogical universities.

The popularity of sports and recreational receivers of the global navigation satellite systems is steadily increasing and provides athletes, coaches, and scientists with a wealth of information on movement occurring both horizontally and vertically. Under mountainous conditions, considering the effort put in by the athlete as well as their safety, the elevation parameter appears to be particularly relevant. The aim of the study was to propose a methodology for assessing sports receivers in terms of their determination of the elevation component based on digital elevation models while paying attention to the appropriate measures for testing these devices. The methodology was applied for wrist-worn global navigation satellite systems' receivers used by the participants of an uphill running event. In terms of elevation determination, the most accurate three receivers (same model) were those supported by the barometric altimeter, in which the Root Mean Square result obtained ranged from 3.6 to 4.1 m. The majority of receivers underestimated the total elevation gain, the mean value of which was −3.8%, which does not appear to be affected by the reception of two global navigation satellite systems or the use of a barometric altimeter. The error characteristics were common within the group of receivers of a particular manufacturer. [ABSTRACT FROM AUTHOR]

The presented review discusses recent research on human echolocation by blind and sighted subjects, aiming to classify and evaluate the methodologies most commonly used when testing active echolocation methods. Most of the reviewed studies compared small groups of both blind and sighted volunteers, although one in four studies used sighted testers only. The most common trial procedure was for volunteers to detect or localize static obstacles, e.g., discs, boards, or walls at distances ranging from a few centimeters to several meters. Other tasks also included comparing or categorizing objects. Few studies utilized walking in real or virtual environments. Most trials were conducted in natural acoustic conditions, as subjects are marginally less likely to correctly echolocate in anechoic or acoustically dampened rooms. Aside from live echolocation tests, other methodologies included the use of binaural recordings, artificial echoes or rendered virtual audio. The sounds most frequently used in the tests were natural sounds such as the palatal mouth click and finger snapping. Several studies have focused on the use of artificially generated sounds, such as noise or synthetic clicks. A promising conclusion from all the reviewed studies is that both blind and sighted persons can efficiently learn echolocation.

Introduction. Until now, the requirements for manual and automatic couplers for locomotive-hauled passenger carriages and electric trains have been completely identical, despite the significantly lower level of longitudinal forces during the movement of multi-unit rolling stock with distributed traction. The introduction of specialised designs of coupling devices for electric trains led to the development of strength requirements that enable the creation of new models with smaller dimensions and weight. Operating experience has shown that parts of couplings may be destroyed, leading to the uncoupling of trains. Fatigue damage may cause accidents. However, there were studies of the draft loads of electric trains couplers in operation, on the basis of which it was possible to develop regulatory requirements for specialised coupling devices.Materials and methods. The authors measured the forces acting in the couplings of electric trains of various categories and types during normal operation, as well as the frequencies of the occurrence of forces of various levels. The article includes histograms based on the results of processing the received data showing the distribution of longitudinal forces acting on the inter-car couplers and the parameter characterising the accumulation of fatigue damage per 100,000 km. Results. According to the results of processing of the experimental data, the calculation of the accumulation of fatigue damage to the couplers was carried out and the requirements for their expected service life were established. Test procedures have also been developed to evaluate strength and fatigue resistance under high-cycle and low-cycle loading conditions. The article provides ground for introducing a correction factor into the procedure for processing test results, which makes it possible to perform life tests on equipment with different values of the load cycle asymmetry factor.Discussion and conclusion. The authors have evaluated the draft loads in coupling devices during the operation of electric trains, on the basis of which technical requirements and test methods were developed and approved by JSC Russian Railways. Development and acceptance of all new models of coupling devices for electric trains will be carried out in accordance with these regulatory documents.

Jet engine components need protective coatings to function against both high‐temperature and environmental effects. Ingested calcium–magnesium–aluminosilicates (CMAS) dust particulates are extremely detrimental to the life of the coatings. However, many methods exist to investigate the infiltration of CMAS into these coatings with each method exploring a different aspect of the degradation process. To probe the overlap in these methods, this study focuses on the effect of grain size, areal density, and aspect ratio on the infiltration of CMAS into yttria stabilized zirconia. The infiltration depths ranged from 6 up to 85 µm depending on the test conditions. [ABSTRACT FROM AUTHOR]

The presented review discusses recent research on human echolocation by blind and sighted subjects, aiming to classify and evaluate the methodologies most commonly used when testing active echolocation methods. Most of the reviewed studies compared small groups of both blind and sighted volunteers, although one in four studies used sighted testers only. The most common trial procedure was for volunteers to detect or localize static obstacles, e.g., discs, boards, or walls at distances ranging from a few centimeters to several meters. Other tasks also included comparing or categorizing objects. Few studies utilized walking in real or virtual environments. Most trials were conducted in natural acoustic conditions, as subjects are marginally less likely to correctly echolocate in anechoic or acoustically dampened rooms. Aside from live echolocation tests, other methodologies included the use of binaural recordings, artificial echoes or rendered virtual audio. The sounds most frequently used in the tests were natural sounds such as the palatal mouth click and finger snapping. Several studies have focused on the use of artificially generated sounds, such as noise or synthetic clicks. A promising conclusion from all the reviewed studies is that both blind and sighted persons can efficiently learn echolocation. [ABSTRACT FROM AUTHOR]

Remote test settings have become more common due to COVID-19. This paper presents two user tests focusing on the usability and user experience of an augmented reality-related solution. We describe the proceeding of the tests from the perspective of what has been conducted face-to-face and remotely. Thereafter, the appropriateness of the used test methodology is evaluated based on (i) the acquired results, (ii) the ease of using and understanding the methods and (iii) the test atmosphere. The physical presence of a person providing technical support to the test participant proved vital for augmented reality-related testing; the location of other test organisers appears more indifferent. Finally, we present the perspectives to contemplate when choosing between face-to-face and remote features in the test setting. [ABSTRACT FROM AUTHOR]

Digital TV (DTV) receivers are usually submitted to testing systems for conformity and robustness assessment, and their approval implies correct operation under a given DTV specification protocol. However, many broadcasters inadvertently misconfigure their devices and transmit the wrong information concerning data structures and protocol format. Since most receivers were not designed to operate under such conditions, malfunction and incorrect behaviour may be noticed, often recognized as field problems, thus compromising a given system's operation. Moreover, the way those problems are usually introduced in DTV signals presents some randomness, but with known restrictions given by the underlying transport protocols used in DTV systems, which resembles fuzzing techniques. Indeed, everything may happen since any deviation can incur problems, depending on each specific implementation. This error scenario is addressed here, and a novel receiver robustness evaluation methodology based on non‐compliance tests using grammar‐based guided fuzzing is proposed. In particular, devices are submitted to unforeseen conditions and incorrect configuration. They are created with guided fuzzing based on real problems, protocol structure, and system architecture to provide resources for handling them, thus ensuring correct operation. Experiments using such a fuzzing scheme have shown its efficacy and provided opportunities to improve robustness regarding commercial DTV platforms. [ABSTRACT FROM AUTHOR]

Abstract This article aims to propose a new approach to the empirical testing of the pecking order theory that tackles commonly reported issues and apply it to the analysis of Brazilian companies. The main gaps bridged herein are the lack of clear definitions for safe debt and financial slack; the lack of control, in regressions, for the financing sources’ capabilities; and the failure to consider future investment opportunities in financing analyses. We adopt methods that enable controlling for the information the companies have about each financing source’s capabilities, at the time their financing decisions are made, while taking current and future investment opportunities into account. The proposed methodology offers a rather controlled environment to test the pecking order theory, which can be adapted to study other topics in finance, supporting advances in understanding the raising and allocation of funds by listed companies. Four integrated financing and cash holding policies are defined, which lead to different expected internal deficits (or surpluses). The relationships between these deficits (or surpluses), at different levels, and the flows that are observed at the external sources of funds are analyzed in cross-section and panel data quantile regressions, controlling for each source’s capabilities, in unbalanced data panels with 4,465 observations of 223 companies. By studying the relationships between expected internal financing deficits (or surpluses) and the flows that are observed at the external sources of funds, we contribute with a new capital structure testing methodology, and we find strong evidence that Brazilian listed companies follow the pecking order theory.

The methodology for testing pipeline steels is suggested on the assumption that for the destruction of pipes in field oil pipelines by the mechanism of grooving corrosion the simultaneous fulfillment of such conditions as the occurrence of scratches on the lower generatrix of the pipe, eventually growing into a channel in the form of a groove, emulsion enrichment with oxygen, presence of pipe wall metal in a stressed state, presence of chlorine-ion in the oil-water emulsion is required. Tests are suggested to be carried out in 3 % aqueous solution of NaCl with continuous aeration by air on bent plates 150×15×3 mm, made of the analyzed steel, the middle part of which is under the action of residual stresses σres, close to the level of maximum equivalent stresses σeqv in the wall of the oil pipeline, with the presence of a cut on this part on the inner side of the plate as an initiator of additional mechanical stresses. Using the value of the modulus of normal elasticity of the analyzed steel, the degree of residual strain of the elastic-plastic body from this material, corresponding to the value σres ≈ σeqv is calculated, based on which the plates are bent to the required deflection angle, after which the cut is applied to them. After keeping the plates in the corrosive medium for each of them the increase in depth of the cut as a result of corrosion of the walls by the corrosive medium is analyzed, from which the rate of steel K by the mechanism of grooving corrosion is calculated taking into account the duration of tests. Corrosion rate values for two pipe steel grades determined by the suggested procedure are given. The comparison of K values obtained leads to the conclusion about the higher resistance to grooving corrosion of 09G2S steel.

The paper presents a new methodology for short-term (5–25 min) benchtop tests to evaluate the effectiveness of magnetic treatment of feed water for reducing mineral scaling on a reverse osmosis (RO) membrane. Scale deposition is measured at a controlled level of salt supersaturation in water flowing through an RO unit in once-through mode. A magnetic water conditioner is tested in a transient flow regime when variations of the permeate flux along the flow path are insignificant. Scale formation under these conditions is governed by salt crystallization on the membrane surface. The proposed method was implemented to investigate the influence of magnetic treatment on gypsum deposition on RO membranes in supersaturated aqueous CaSO4/NaCl solutions. The effects of magnetic water treatment on scale formation under our experimental conditions were found to be statistically insignificant with a confidence level of 95%. However, this outcome should not be considered to negate the potential efficiency of magnetic water treatment in specific applications. The proposed methodology of testing under a controlled level of salt supersaturation will also be useful for evaluating the efficiency of other water treatment technologies.

Relating phosphorus (P) fertilization to crop demand in sugarcane (Saccharum spp.) grown on mineral soils in southern Florida is critical for minimized environmental impact and sustained crop production. Previous P fertilizer recommendations date to 1974 and so revised recommendations are needed for sugarcane on these soils which account for 29% of the crop in Florida. Phosphorus rate studies were conducted at seven field locations (16 total site-crop years) with P rates of 0 to 73 kg P ha−1 at Site 1 and 0 to 61 kg P ha−1 at Sites 2–7 using small-plots (82 or 120 m2 plots) on four soil series representing Spodosols, Entisols, and Alfisols. Soil P extractions with Mehlich 3, 0.7 M ammonium acetate, and water were evaluated in relation to relative sucrose yield and leaf P concentrations. Mehlich 3 had stronger relationships with relative yield and leaf P and a Mehlich 3 P value of 80 g m−3 is proposed as a critical value above which no P fertilizer would be required. Without added P fertilizer, Mehlich 3-extractable P values decreased annually by an average of 20%. Results suggest maintaining 36.7 kg P ha−1 as the maximum P fertilizer rate for sugarcane in mineral soils. Abbreviations: EAA: Everglades Agricultural Area; BMPs: best management practices; DAP: diammonium phosphate; MCH: megagram (Mg) cane ha−1; MSH: megagram (Mg) sucrose ha−1; KSM: kg sucrose Mg−1 cane; M3P: Mehlich 3-extractable soil P; AmAcP: ammonium acetate-extractable soil P; Pw: water-extractable soil P [ABSTRACT FROM AUTHOR]

This research is aimed at evaluating the effect of low-cycle fatigue on a newly designed hybrid sandwich ski structure to determine the changes that may occur due to cyclic loading and thus affect its use. This is primarily concerned with the fatigue behavior of the tested ski over different time intervals simulating its seasonal use and its effect on the mechanical properties of the ski, i.e., the durability and integrity of the individual layers of the sandwich ski structure. The ski was subjected to 70,000 deflections by moving the crossbar by 60 mm according to the ski deflection calculation in the arch. The results of the cyclic tests of the engineered ski design showed no significant changes in the ski during loading. The average force required to achieve deflection in the first 10,000 cycles was 514.0 ± 4.2 N. Thereafter, a secondary hardening of the structure occurred during relaxation and the force required increased slightly to 543.6 ± 1.7 N. The required force fluctuated slightly during the measurements and in the last series the value was 540.4 ± 0.8 N. Low-cycle fatigue did not have a significant effect on the mechanical properties of the ski; there was no change in shape or visual delamination of the individual layers of the structure. From the cross-section, local delamination was demonstrated by image analysis, especially between the Wood core and the composite layers E-Glass biaxial and Carbon triaxial. [ABSTRACT FROM AUTHOR]

Precast concrete insulated sandwich wall panels have been commonly used as exterior load bearing or cladding wall panels on building structures. These panels are usually designed as composite, partially composite, or noncomposite, depending on the strength of the shear connectors connecting the two exterior concrete wythes. Various proprietary available shear connectors are used to achieve the required degree of composite action. The design information of the shear connectors is provided by the connector supplier based on testing results. Currently, there is no universally accepted method of testing composite shear connectors in practice or in the literature, however, connector suppliers usually use one of two testing methodologies recommended by the International Code Council–Evaluation Service, namely, AC320 or AC422, respectively. It is not known which test provides a better measurement of design values such as strength and stiffness, and there is no such comparison in the literature. In this study, 68 pushoff experiments were presented to evaluate the difference between these two testing methodologies. The testing program consisted of 20 single shear specimens and 48 double shear specimens. Three different commercially available shear connectors were used as well as variable insulation wythe thicknesses. The results were statistically analyzed. Large differences in the measured connectors' shear strengths and stiffness were observed between the two testing methods, with AC422 providing consistently larger ultimate shear and secant stiffness, but considerably more variability. Large-scale flexural specimens from the literature were modeled using AC320 and AC422 as-measured results, and AC422 tests were found to predict deflections, cracking, and strength more accurately. It was concluded that AC422 produces a more accurate measure of connector properties, but suffers from large variability, resulting in a recommendation that further investigation into changing testing parameters and/or methods is warranted to reduce this variability. [ABSTRACT FROM AUTHOR]

The paper discusses the task of organizing the usability testing of web applications that are in pilot or industrial operation. A usability testing technique is described that combines the development, debugging and execution of test scenarios, and analysis of the received test data. The development of test scenarios is based: on the use of the accumulated experience of users who have already worked with this application or with another, similar in functionality; on the use of web analytics, which can provide scenarios of the behavior of user data on the site; and on the use of statistical data on visits to specific pages. Simultaneously with this approach, a different approach is used in the construction of tests. It is based on the development of tests aimed at identifying defects in the program. Debugging and execution of test tasks is carried out in the same way as it is realized when performing functional testing of web applications using testing automation tools. In addition, the analysis of the data obtained during the operation using web analytics makes it possible to form a group of respondent testers, whose capabilities reflect the capabilities of the entire set of probable users of this web application. The approaches outlined in the work were put into practice. As an example, the article provides test data for the page of the admissions committee of MIREA – Russian Technological University – priem.mirea.ru. The obtained experimental data showed that, despite testing the usability of software at the development stages, some errors in the operation of web applications remain undetected. The cost of detecting and eliminating these errors increases significantly. Therefore, it is recommended in the work to increase the level of usability already in the early stages of development. In particular, for the operational prediction of the level of usability, it is desirable to have mathematical tools for modeling the behavior of the designed system and the user.

Natural stone is an important component of historical heritage (buildings and art objects such as sculptures or rock engravings), and it is still widely used in contemporary works. Soluble salts are the main erosive agent in the built environment, and we review here comparative studies that subject the same rock type to testing with different salt solutions. The results mostly support the accepted notion of the major impact of sodium sulphate, although there are some exceptions. The effects of sodium chloride and calcium sulphate deserve specific discussion given field information on the relevance of these specific salts in the built environment. We relate the information collected to the issues of risk assessment (considering both geochemical conditions and salt effects) and conservation interventions (highlighting the interest of tests that do not produce damage to susceptible materials) and present some methodological suggestions to avoid a case study culture. [ABSTRACT FROM AUTHOR]

The methodology, developed for active testing of electronic devices under the radiations, is presented. The test set-up includes a gamma-ray facility, the hardware board/fixtures and the software tools purposely designed and realized. The methodology is so wide-ranging to allow us the verification of different classes of electronic devices, even if only application examples for static random access memory modules are reported.

An N1 vehicle model is created, which allows for changing suspension parameters and conditions of experimental performance. A methodology of computer testing performance for vehicle ride comfort and stability service properties’ characterization in a virtual environment is proposed. Vehicle suspension system modelling and simulation are performed. The results of the N1 vehicle suspension system from full-scale laboratory and road tests are given.

This study was conducted to investigate the various boron fractions in olive tree grown soils. The correlations between boron fractions in leaves, fruits and soil properties were examined. For this purpose cv "Gemlik" olive (Olea europaea L.) orchards were visited. Soil samples from 0–30 cm and 30–60 cm deep, the leaf and fruit samples were collected. The greatest proportion of total soil boron is present in residual form (85–88%). It is followed by organically bound B (2.84–4.50%), specifically adsorbed on soil colloid surfaces (0.93–1.31%), oxides (manganese oxyhydroxides, amorphous Fe and Al oxides, crystalline Fe and Al oxides) bound B (7.27–8.31%). The smallest one readily soluble (extracting plant available) boron values were composed of only 0.40–0.50% of total boron ranging. To determine readily soluble boron five different extraction solutions were in the order Hot water ˃ 0.01 M CaCl2 ˃ 1 M NH4OAc ˃ 0.1 M KCl ˃ 0.005 M DTPA. Fruit boron concentration and soil boron fractions showed close correlations than leaf boron concentration. [ABSTRACT FROM AUTHOR]

Testing embedded systems software has become a costly activity as these systems become more complex to fulfill rising needs. Testing processes should be both effective and affordable. An ideal testing process should begin with validated requirements and begin as early as possible so that requirements defects can be fixed before they propagate and become more difficult to address. Furthermore, the testing process should facilitate test procedures creation and automate their execution. We propose a novel methodology for testing functional requirements. The methodology activities include standard notations, such as UCM for modeling scenarios derived from requirements, TDL for describing test cases and TTCN-3 for executing test procedures; other test scripting languages can also be used with our methodology. Furthermore, the automation of the methodology generates test artifacts through model transformation. The main goals of this test methodology are to leverage requirements represented as scenarios, to replace the natural language test case descriptions with test scenarios in TDL, and to generate executable test procedures. Demonstration of the feasibility of the proposed approach is based on a public case study. An empirical evaluation of our approach is given using a case study from the avionics domain. [ABSTRACT FROM AUTHOR]

The maximum ceiling height of the FM Global laboratory is 18.3 m. Therefore, fire protection solutions for warehouses with taller ceilings cannot be directly validated through full-scale testing. This work develops a methodology to obtain the key processes of fire growth, spray-plume interaction, and fire suppression response for an 18.9 m high roll-paper storage under a 24.4 m tall ceiling. The proposed methodology uses a heptane burner assembly at the base of the commodity array to match the fire heat release and growth rate to that of a taller storage exceeding lab capability. The burner assembly included six heptane burners and two air ducts. A series of experiments was conducted to characterize the burner design, model the fire growth in the free-burn stage, and validate controlled and uncontrolled fires in terms of the number of activated sprinklers. A final large-scale fire test used a 12.8 m high storage of Kraft paper with the burner assembly under an 18.3 m tall ceiling to validate protection recommendations for Kraft paper stored 18.9 m high under a 24.4 m tall ceiling. The test demonstrated full suppression using K360 (K-factor, lpm/bar1/2), fast response, pendent sprinklers with a temperature rating of 74 °C, supplied with a water pressure of 8.3 bar. • Developed a testing methodology for ceilings exceeding laboratory limits. • Designed a burner assembly as a fire source to lower virtual fire origin. • Verified the methodology by running a series of large-scale experiments. • Obtained data to verify protection of 18.9 m high storage under 24.4 m tall ceiling. [ABSTRACT FROM AUTHOR]

Abstract Certification of hydrogen sensors to meet standards often prescribes using large-volume test chambers [1,2]. However, feedback from stakeholders such as sensor manufacturers and end-users indicates that chamber test methods are often viewed as too slow and expensive for routine assessment. Flow-through test methods are potentially an efficient and cost-effective alternative for sensor performance assessment. A large number of sensors can be simultaneously tested, in series or in parallel, with an appropriate flow-through test fixture. The recent development of sensors with response times of less than 1s mandates improvements in equipment and methodology to properly capture the performance of this new generation of fast sensors; flow methods are a viable approach for accurate response and recovery time determinations, but there are potential drawbacks. According to ISO 26142 [1], flow-through test methods may not properly simulate ambient applications. In chamber test methods, gas transport to the sensor is dominated by diffusion which is viewed by some users as mimicking deployment in rooms and other confined spaces. Conversely, in flow-through methods, forced flow transports the gas to the sensing element. The advective flow dynamics may induce changes in the sensor behaviour relative to the quasi-quiescent condition that may prevail in chamber test methods. The aim of the current activity in the JRC and NREL sensor laboratories [3,4] is to develop a validated flow-through apparatus and methods for hydrogen sensor performance testing. In addition to minimizing the impact on sensor behaviour induced by differences in flow dynamics, challenges associated with flow-through methods include the ability to control environmental parameters (humidity, pressure and temperature) during the test and changes in the test gas composition induced by chemical reactions with upstream sensors. Guidelines on flow-through test apparatus design and protocols for the evaluation of hydrogen sensor performance have been developed. Various commercial sensor platforms (e.g., thermal conductivity, catalytic and metal semiconductor) were used to demonstrate the advantages and issues with the flow-through methodology. Highlights • Validation of flow-through methodology for hydrogen sensor testing. • Comparison between chamber and flow-through methodologies. • Protocols for the evaluation of hydrogen sensor performance. • Guidelines for flow-through testing apparatus deployment. [ABSTRACT FROM AUTHOR]

Using CFRP anchors to prevent the premature debonding failure of CFRP strips from concrete substrate is gaining acceptance. Although adequate CFRP anchors can fully develop the strength of CFRP strips, few recommendations for designing CFRP anchors are available. Based on experimental results obtained from 38 tests, a testing methodology using design strip strength is presented to evaluate the quality of CFRP anchors and to identify the design parameters including the strength ratio of CFRP anchor to CFRP strip, the strip width, the concrete strength, the fan angle, the embedment length, the bend radius, the hole diameter, the CFRP patch, the bond length and the bond condition. Design recommendations and installation procedures are also presented to ensure the desired performance of the anchorage system. [ABSTRACT FROM AUTHOR]

The amount of potentially mineralizable nitrogen (PMN) in early spring is critical to winter wheat production because maximum nitrogen (N) uptake begins then. We evaluated the Haney-Brinton CO2-burst method for quantifying PMN in early spring from biosolids fall-applied to soft red winter wheat (Triticum aestivum L.). Anaerobically digested and lime stabilized biosolids were fall-applied at 0, 50 and 100 kg PAN ha−1 at six locations in the Virginia Coastal Plain in 2013. The Haney-Brinton CO2-burst method did not provide an accurate estimation of spring PAN for biosolids applied in the fall for no-till winter wheat. The sum of preplant soil inorganic N and PMN of the unamended soil was better related to grain yield than PMN alone. The Haney-Brinton CO2-burst method is inadequate for use in no-till management but may provide an accurate mid-season estimate of winter wheat yield potential when used in combination with pre-plant soil inorganic N. [ABSTRACT FROM AUTHOR]

This paper presents a procedure for detecting and quantifying defects in reinforced concrete structures by us-ing the method of active infrared thermography (IRT). For quantitative analysis, a methodology of thermal stimulation of concrete specimens and post-processing of the gathered data was developed. Presented methodology uses principles of step heating (SH) thermography, pulsed phase (PPT) thermography, principal component thermography (PCT) and correlation operators technique. A short descriptions of the post-processing methods used in the research is also provided in the paper. All three post-processing methods i.e. PPT, PCT and correlation operators technique have shown the pos-sibility to enhance the defect detection in concrete structures in comparison to raw thermograms. According to the data accessible to the authors, in presented research, correlation operators and PCT post-processing techniques are being suc-cessfully used for the first time for defect detection within concrete structures. The results of the research clearly show the possibility of using active IRT for the detection and assessment of defect depth (quantification) in reinforced concrete structures with the measurement error within 10%.

An N1 vehicle model is created, which allows for changing suspension parameters and conditions of experimental performance. A methodology of computer testing performance for vehicle ride comfort and stability service properties' characterization in a virtual environment is proposed. Vehicle suspension system modelling and simulation are performed. The results of the N1 vehicle suspension system from full-scale laboratory and road tests are given. [ABSTRACT FROM AUTHOR]

This paper presents a procedure for detecting and quantifying defects in reinforced concrete structures by using the method of active infrared thermography (IRT). For quantitative analysis, a methodology of thermal stimulation of concrete specimens and post-processing of the gathered data was developed. Presented methodology uses principles of step heating (SH) thermography, pulsed phase (PPT) thermography, principal component thermography (PCT) and correlation operators technique. A short descriptions of the post-processing methods used in the research is also provided in the paper. All three post-processing methods i.e. PPT, PCT and correlation operators technique have shown the possibility to enhance the defect detection in concrete structures in comparison to raw thermograms. According to the data accessible to the authors, in presented research, correlation operators and PCT post-processing techniques are being successfully used for the first time for defect detection within concrete structures. The results of the research clearly show the possibility of using active IRT for the detection and assessment of defect depth (quantification) in reinforced concrete structures with the measurement error within 10%. [ABSTRACT FROM PUBLISHER]

The paper presents a new methodology for short-term (5-25 min) benchtop tests to evaluate the effectiveness of magnetic treatment of feed water for reducing mineral scaling on a reverse osmosis (RO) membrane. Scale deposition is measured at a controlled level of salt supersaturation in water flowing through an RO unit in once-through mode. A magnetic water conditioner is tested in a transient flow regime when variations of the permeate flux along the flow path are insignificant. Scale formation under these conditions is governed by salt crystallization on the membrane surface. The proposed method was implemented to investigate the influence of magnetic treatment on gypsum deposition on RO membranes in supersaturated aqueous CaSO 4 /NaCl solutions. The effects of magnetic water treatment on scale formation under our experimental conditions were found to be statistically insignificant with a confidence level of 95%. However, this outcome should not be considered to negate the potential efficiency of magnetic water treatment in specific applications. The proposed methodology of testing under a controlled level of salt supersaturation will also be useful for evaluating the efficiency of other water treatment technologies.

Labile soil dissolved organic carbon (DOC) and heat-extracted carbon (HEC) are sensitive indicators of changing soil organic carbon (SOC) stocks. Isotope ratio mass spectrometry (IRMS) is an important tool for studying SOC turnover and soil biological function. Several complications are involved in measuring DOC/HEC, for example salt ionic strength; solution pH; and anionic damage to elemental analyzer-IRMS. We evaluated a method for DOC/HEC analysis with 0.1 M potassium phosphate buffer (PPB). This method was strongly correlated with commonly used carbon (C) extractants for C quantification. Carbon-13 comparisons between DOC/HEC extracted with Milli-Q water and PPB were similar. The δ13C (‰) values of particulate OC and DOC were similar, whereas the relationship between humic OC and HEC was soil specific. An incubation experiment demonstrated that DOC/HEC δ13C (‰) successfully explained respired microbial carbon dioxide over 90 days. We conclude that this method represents an alternative for DOC/HEC quantification and δ13C (‰) analyses. [ABSTRACT FROM AUTHOR]