Large-scale Field Tests Research Articles

Numerical study of bubble screens for mitigating salt intrusion in sea locks

In order to mitigate the effects of salt water intrusion at sea locks, bubble screens are installed which act as a barrier between the dense sea water and the fresh water inland. In order to optimize the design of the bubble screen, in this study a state-of-the-art numerical model is developed based on the Euler-Lagrange CFD method which is expanded with a simple salt balance and concentration-density coupling. The model has been validated by means of experimental results on a laboratory-scale bubble screen. The liquid circulation and entrainment have been investigated for two types of bubble injection methods. It is found that the bubble screen is successful as a separator of salt and fresh water in an initial period of τsep=30 seconds but acts more as a mixer at later times due to the swaying of the screen. The rate of the mixing increases with the air flow rate. Two mechanisms of salt intrusion are distinguished; a delayed density current along the bottom and entrained liquid being circulated through the domain back to the screen. An optimum in air flow rate is found at a Froude air number Frair=0.91. Bubble screen behaviour is also checked at the lock-scale using lock-scale geometry and simulations. The amount of salt transmitted agrees well with the large-scale field tests up until the reported Frair numbers but Frair > > 1 need to be tested to check for the optimum as found in the lab-scale tests.

VOLLEYBALL SMASH SKILL TRAINING MODEL USING RUBBER TIRE AIDS FOR STUDENTS OF SMK

The purpose of this study is to produce a product in the form of volleyball smash skills training methods using rubber tire aids to improve smash skills in volleyball games. The research method used is the development of Borg and Gall. Based on the data collected, it is known through the material expert and media expert tests conducted twice each, obtained the results of the material I test with a percentage of 68.75% (quite valid) and the results of II with an average of 87.50% ( valid). While the results of media experts obtained results I amounted to 65.40% (quite valid) and results II with an average of 84.62% (valid). From small scale trials (N = 8), results with an average percentage of 81.19% (valid) and large scale field tests (N = 30) obtained results with a percentage of 90.83% (valid). Based on the results of the data obtained, it can be concluded that the product development of the smash skills training model with rubber tire aids for volleyball extracurricular athletes after going through several stages including preliminary test stages, expert validation tests, small and large group tests, model effectiveness test concluded can be accepted by users, especially schools that have and are active in coaching volleyball.

Large-scale field test on abandoned deep anhydrite mine-out for reuse as crude oil storage – A case study

The reuse of abandoned anhydrite mine-outs has significant potential to reduce the cost and period of construction of crude oil storage facilities and provides a new option for exploiting underground space. Based on a case study of the Anhui Hengtai anhydrite mine located in East China, this study formulated a comprehensive field test program to investigate its tightness and stability and evaluate its feasibility for reuse as crude oil storage. Combining the field tests with laboratory tests, the underlying mechanism of interaction among anhydrite, water, and crude oil was revealed, and the stability and tightness of anhydrite mine-out during the storage of crude oil was evaluated. The results indicate that the anhydrite mine-out has good stability and tightness, which is not affected by the presence of crude oil. Additionally, the anhydrite has negligible effects on the crude oil quality; however, the presence of water reduces the strength of anhydrite rock, which has the potential to affect the stability and tightness of the mine-out. It is concluded that the anhydrite mine-out has the potential to be used as underground crude oil storage space, but the long-term contact between anhydrite rock and water should be avoided. This work is expected to benefit future underground space exploitation through reuse of mine-out.

A large-scale field test on sand compaction piles including three-dimensional numerical analysis

This paper presents a large-scale field test study performed on soft ground improved by a set of 216 sand compaction piles in a mesh of 12 × 18 columns, with plan dimensions of 32.2 m × 21.4 m loaded with anchor piles loading system. The objective of this study was to verify the performance of foundation improvements with sand compaction piles for the future immersed tunnel. The field test was also useful to calibrate a numerical model for predicting the behaviour of the permanent immersed tunnel on sand compaction piles composite foundation. Three-dimensional finite element analysis was firstly carried out and the results of field measurements and numerical calculations were compared. In general, the numerical calculations of vertical displacements reproduced the field measurements with satisfactory accuracy. Calculations of effective stress and stress concentration ratio had less satisfactory agreement, and some reasons are provided for this.

A large-scale field test on sand compaction piles including three-dimensional numerical analysis

This paper presents a large-scale field test study performed on soft ground improved by a set of 216 sand compaction piles in a mesh of 12 × 18 columns, with plan dimensions of 32.2 m × 21.4 m loaded with anchor piles loading system. The objective of this study was to verify the performance of foundation improvements with sand compaction piles for the future immersed tunnel. The field test was also useful to calibrate a numerical model for predicting the behaviour of the permanent immersed tunnel on sand compaction piles composite foundation. Three-dimensional finite element analysis was firstly carried out and the results of field measurements and numerical calculations were compared. In general, the numerical calculations of vertical displacements reproduced the field measurements with satisfactory accuracy. Calculations of effective stress and stress concentration ratio had less satisfactory agreement, and some reasons are provided for this.

Application of the ESMO-Magnitude of Clinical Benefit Scale (V.1.1) to the field of early breast cancer therapies

Click here to listen to the PodcastBackgroundThe European Society for Medical Oncology-Magnitude of Clinical Benefit Scale (ESMO-MCBS) is a validated value scale for solid tumour anticancer treatments. Form 1 of the ESMO-MCBS, used to grade therapies with curative intent including adjuvant therapies, has only been evaluated for a limited number of studies. This is the first large-scale field testing in early breast cancer to assess the applicability of the scale to this data set and the reasonableness of derived scores and to identify any shortcomings to be addressed in future modifications of the scale.MethodRepresentative key studies and meta-analyses of the major modalities of adjuvant systemic therapy of breast cancer were identified for each of the major clinical scenarios (HER2-positive, HER2-negative, endocrine-responsive) and were graded with form 1 of the ESMO-MCBS. These generated scores were reviewed by a panel of experts for reasonableness. Shortcomings and issues related to the application of the scale and interpretation of results were identified and critically evaluated.ResultsSixty-five studies were eligible for evaluation: 59 individual studies and 6 meta-analyses. These studies incorporated 101 therapeutic comparisons, 61 of which were scorable. Review of the generated scores indicated that, with few exceptions, they generally reflected contemporary standards of practice. Six shortcomings were identified related to grading based on disease-free survival (DFS), lack of information regarding acute and long-term toxicity and an inability to grade single-arm de-escalation scales.ConclusionsForm 1 of the ESMO-MCBS is a robust tool for the evaluation of the magnitude of benefit studies in early breast cancer. The scale can be further improved by addressing issues related to grading based on DFS, annotating grades with information regarding acute and long-term toxicity and developing an approach to grade single-arm de-escalation studies.

Towards higher temperatures in nuclear waste repositories

Recently, there is a tendency to explore the possibility of increasing the maximum design temperature in deep geological repositories for high-level nuclear waste and spent fuel. In the paper, a number of issues related to the use of higher temperatures are reviewed. Both bentonite barriers and argillaceous host rocks are addressed. An application involving the modelling of a large-scale field test conducted at a maximum temperature of 140ºC is presented. It is shown that currently available theoretical formulations and computer codes are capable to deal with temperatures above 100ºC and to reproduce satisfactorily the thermally-induced overpressures in the rock.

Localization of oil slicks and controlled burning at spill areas

The study is devoted to the development of oil spill response methods, in particular, the method of controlled oil burning using herders under field experimental conditions, as close as possible to real ones. A previously conducted study [1] has found conditions and effectiveness of Siltech OP-40 and ThickSlick 6535 herders for Kashagan oil in artificial sea water with salinity typical for Kazakhstani sector of the Caspian Sea. Based on the results of this work, which showed the effectiveness of herders in relation to weathered Kashagan oil, a large-scale field test was conducted on the controlled burning of oil in the harbor of the North Caspian environmental base for oil spill response in the area of Damba village, Atyrau region. In a field test, 400 l of oil was spilled, the oil slick was localized and thickened using the OR-40 herder, and oil was burned with an efficiency of 95%.

Measuring Social Motivation in Autism Spectrum Disorder: Development of the Social Motivation Interview.

Social motivation in individuals with ASD is inferred from the observation of overt behaviors and neurological correlates. Motivation, however, can be distinguishable from overt behavior and neurologic reactivity. Nevertheless, few studies have examined the cognitive processes that may influence goal-directed tasks involved in social interaction. This study addressed this conceptual need by developing a novel interview. The social motivation interview (SMI) assesses for internal cognitions as they relate to social motivation by evaluating social desire, interest, and behaviors in eighteen children with ASD (Myears = 12.84). Pilot testing suggested feasibility of administration, user satisfaction, and promising psychometric properties. Future examination of the SMI in large-scale field testing is warranted.

Dynamic compaction of a thick soil-stone fill: Dynamic response and strengthening mechanisms

A large-scale field test to investigate vibration velocities from dynamic compaction of soil-aggregate mixture in a fill at a Chengde airport construction site, China, was carried out. The propagation and evolution of the vibration waveforms, wave amplitudes, and wave frequencies were analyzed and the mechanism by which the strength of the soil-aggregate fill was reinforced by the tamping energy was studied. The results show that there are only two vibration forms, shock waves and vibration waves, in the soil-aggregate mixture under dynamic compaction. The dominant vibration frequency and optimum frequency band for dynamic compaction are determined and the concept of critical elastic vibration velocity for soil-aggregate mixtures is proposed. A method for determining the magnitude of this vibration is demonstrated. During and after compaction, the fill could be divided into three zones, an impact reinforced zone, plastic stress wave reinforced zone, and elastic area in which the soil is not reinforced. These zones are defined by the spatial distribution of the vibration velocities and the correspondingly increased soil densities. Finally, the dynamic compaction reinforcement mechanism for a coarse-grained soil-aggregate mixture is explained and the reinforcement process is divided into two stages. In addition, a suggestion for the best layer thickness for dynamic compaction of fill is proposed.

Growth Response and Developing Simple Test Method for Waterlogging Stress Tolerance in Soybean

The global climate changes and insufficient drainage system could cause the flooding with significant yield losses in crop production. Despite the severity of the flooding, the main reason for currently limited research progress is the lack of resistant resources. This study aimed to identify the main indicator to waterlogging stress and suggest a simple screening method for waterlogging resistant variety in soybean. We selected 3 resistance resources and 3 susceptible resources based on the results of mass field screen test, which was previously conducted using about 4,000 soybean genetic resources in RDA. Plant height, stem diameter, leaf chlorophyll content, root weight and adventitious root number and weight were used investigated as indicator. Significant changes by waterlogging treatment was not observed in the plant height and stem diameter. However, the chlorophyll content of first trifoliate leaf and emergence of adventitious roots showed a clear difference between the resistant and susceptible resources after 9 days of treatment, even though the growth of roots was reduced overall by waterlogging. The results indicated that the number of adventitious roots and the chlorophyll content of the first trifoliate leaf were an excellent indicator to distinguish resistance and susceptible resources. We also developed simple screening method for waterlogging in soybean. The resistance resource selection was possible within 6 days after waterlogging treatment in green house using the chlorophyll content of the first trifoliate leaf and the number of adventitious roots. The proposed simple screening method could save the time and labor for large scale field test.

Development of a Patient-Reported Outcome Instrument for Patients With Severe Lower Extremity Trauma (LIMB-Q): Protocol for a Multiphase Mixed Methods Study.

BackgroundA current limitation in the care of patients with severe lower extremity traumatic injuries is the lack of a rigorously developed patient-reported outcome (PRO) instrument specific to lower extremity trauma patients.ObjectiveThis mixed methods protocol aims to describe phases I and II of the development of a PRO instrument for lower extremity trauma patients, following international PRO development guidelines.MethodsThe phase I study follows an interpretive description approach. Development of the PRO instrument begins with identifying the concepts that are important to patients, after which a preliminary conceptual framework is devised from a systematic literature review and used to generate an interview guide. Patients aged 18 years or above with limb-threatening lower extremity traumatic injuries resulting in reconstruction, amputation, or amputation after failed reconstruction will be recruited. The subjects will participate in semistructured, in-depth qualitative interviews to identify all important concepts of interest. The qualitative interview data will be coded with top-level domains, themes, and subthemes. The codes will then be utilized to refine the conceptual framework and generate preliminary items and a set of scales. The preliminary scales will be further refined via a process of conducting cognitive debriefing interviews with lower extremity trauma patients and soliciting expert opinions. Phase III will include a large-scale field test, using Rasch measurement theory to analyze the psychometric properties of the instrument; shortening and finalizing the scales; and determining the reliability, validity, and responsiveness of the instrument.ResultsPhases I and II of this study have been funded. Phase I of this study has been completed, and phase II began in January 2019 and is expected to be completed in November 2019. Phase III will begin following the completion of phase II.ConclusionsThis protocol describes the initial phases of development of a novel PRO instrument for use in lower extremity trauma patients.International Registered Report Identifier (IRRID)DERR1-10.2196/14397

Modelling thermal fluxes at the soil surface

This paper investigates the impact that various representations of thermal fluxes at the soil surface have on the estimation of seasonal variations in temperature and stored thermal energy in the soil close to the surface. Three theoretical formulations representing turbulent, non-turbulent and vegetation-covered soil surface conditions are considered. The influence of shading from nearby objects (e.g. vegetation) has also been investigated. Numerical predictions of soil temperature and stored thermal energy are compared with experimental results from a large-scale field test (performed by others). The results of both one-dimensional and two-dimensional simulations are shown to be capable of representing specific aspects of field behaviour. Various sources of meteorological data have been used to define surface boundary conditions. In particular, simulations were performed using (a) data measured on-site, (b) data obtained from the British Atmospheric Data Centre and (c) data generated using analytical expressions from the literature. It was found that correct representation of the heat transfer processes occurring at the soil surface is of critical importance. In particular, it was found that the use of publicly available sources of data, or mathematical/analytical expressions for meteorological data, may be adequate when on-site measurements are not available.

The development of realia for the planetary gear unit to improve students’ understanding on the basics of automatic transmission

This study aims to design and develop a real model of a planetary gear unit providing three kinds of simulation for the basic configurations of the planetary gear unit in which one component member is locked, two members are held together, and two input members works. This is a research and development (R&D) to develop a realia of the planetary gear unit for the learning of automatic transmission basics. The realia is expected to demonstrate how the configurations in which one component member is locked, two members are held together, and two input members moves. This study was carried out through ten stages, namely analyzing potentials and problems, needs analysis, product design, focus group discussion, product development, pilot study (small-scale field test), product revision, large-scale field test, product revision, and final product. The data were collected by questionnaires and were analyzed quantitatively. The product of this study is learning media in the form of realia made of acrylic so that the components are clearly visible and the work of basic configurations of the three gears in the planetary gear unit is easy to understand. These basic arangements can be operationalized on the learning media by applying brakes to the ring, carrier, and sun gears and applying cluthes between the sun and carrier gears, the sun and ring gears, and the carrier and ring gears. Evaluated from its performance, the realia of the planetary gear unit can work well. The shaft can rotate well though some friction generated, the clutch and brake can work on its function, as well as the constituent gears can rotate as its real version does. This is reinforced by the responses from the material and media experts that reveal the product meets the very feasible category.

Impact of foundation modelling in offshore wind turbines: Comparison between simulations and field data

The design of Offshore Wind Turbines (OWTs) relies on integrated simulation tools capable of predicting the system dynamic characteristics and the coupled loads and responses. Despite all efforts to develop accurate integrated models, these often fail to reproduce the measured natural frequencies, partly due to the modelling of the foundation. Several foundation models and calibration approaches have been proposed and compared with small or large scale field tests, where only the soil and the foundation are included. However, there is a lack of more integral validation where the interaction between the foundation and the structure is taken into account. The paper investigates the impact of the foundation model and calibration approach on the simulated response of a monopile-based OWT installed in the North Sea by comparing simulations and full-scale field data. The OWT structure and the environmental actions are implemented in the aero-servo-hydro-elastic code 3DFloat. Two foundation models and two calibration approaches are evaluated. The results indicate that, with a conceptually correct foundation model and a realistic calibration, it is possible to match the measured natural frequency and predict accurate fatigue loads. More accurate predicted loads will reduce uncertainties in the estimated fatigue lifetime and therefore reduce risk in the design.

Laboratory and field tests and distinct element analysis of dry granular flows and segregation processes

Abstract. Natural as well as fill slopes are commonly found in Hong Kong, China, and many other countries, and slope failures with the subsequent debris flows have caused a serious loss of life and property in the past until now. There are various processes and features associated with debris flow which engineers need to know so as to design for the precautionary measures. In this study, experiments on flume tests, friction tests, deposition tests, and rebound tests were carried out for different sizes of balls to determine the parameters required for the modelling of dry granular flow. Different materials and sizes of balls are used in the flume tests, and various flow pattern and segregation phenomena are noticed in the tests. Distinct element modelling (DEM) of dry granular flow is also carried out for the flow process. It is found that for simple cases, the flow process can be modelled reasonably well by DEM, which is crucial for engineers to determine the pattern and impact of granular flow, which will lead to further study in more complicated debris flow. From laboratory tests, large-scale field tests, and numerical simulations of single- and multiple-material tests, it is also found that the particle size will be the most critical factor in the segregation process during granular flow. It is also found from the laboratory tests and numerical simulations that a jump in the flume can help to reduce the final velocity of the granular flow, which is useful for practical purposes.

An Automated Vehicle Fuel Economy Benefits Evaluation Framework Using Real-World Travel and Traffic Data

Increasing automation is a consistent development trend in the automobile industry. However, real-world evaluation of the operational and energy consumption differences between automated vehicles and comparable manually driven vehicles has been limited. This study helps fill the information gap by comparing the operation and fuel economy of vehicles in adaptive cruise control (ACC) and non-ACC modes based on large-scale field test data collected by Volvo Car Corporation (Volvo Cars) from vehicles traveling on the designated project road network in Gothenburg, Sweden. The test vehicles' travel data are classified by driving mode (ACC vs. non-ACC) and driving conditions, which refer to traffic speed and road grade in this study. The results from the data logging fleet are used to estimate the aggregate fuel consumption differences at the Drive Me road-network level for vehicles traveling in ACC vs. non-ACC mode based on appropriately weighting the total amount of travel that took place on the network under different driving conditions. At the ACC penetration levels observed in the field test data, vehicles tended to drive more smoothly in ACC mode than in non-ACC mode. The corresponding travel-weighted fuel consumption rate for vehicles in ACC mode was about 5%-7% lower than for vehicles in non-ACC mode when traveling at similar conditions. Sensitivity analyses impart confidence in this result, and in the future, the established evaluation framework could be used to objectively quantify potential on-road fuel consumption impacts from vehicles with even higher levels of automated driving capability.

INCREASE OF INFORMATION CONTENT WHEN TESTING THE METHOD OF RING LOADING

In the construction of essential structures for the determination of the mechanical properties of large-scale heterogeneous fractured rock soils, people usually rely on the results of more representative large-scale field testing when assigning expected performances. Such large-scale field testing is conducted with the help of concrete stamps or rock pillars, usually with a square in plan outsole, for compression and flat shear, in galleries or in open sites. However, there are drawbacks: the complexity in the implementation and interpretation of the testing data, low informativeness, etc. Due to the rectangular shape of the stamp, a very uneven stress state is implemented at its base during shear. In order to eliminate these drawbacks in 1979 V.L. Kubetskiy offered the method of the ring loading, in which the square base of a stamp (a pillar) was replaced by a ringone, and the shift was carried out by applying a torque load to the stamp. This gives the possibility to realize various stress-strain state in the soil massif, to provide a more uniform contact stress diagram at its base, to obtain technological advantages and additional information during the experiment and to interpret the experimental data more reasonably and reliably using more modern models. Adescription of the method, loading schemes, developed field and laboratory equipment, results and interpretation of field experiments using isotropic and transversally isotropic soil models is given. The ways of method modernization using inventory installations are described. Taking into consideration that the common trend of improving the methods of geomechanical testings is aimed to increase the accuracy and informativity and at the same time to decrease the labor intensity, the method of ring loading which is being improving nowadays is still competitive.

On calculation method for dangerously hydrated loess soil with consideration for elastic-plastic soil properties

On account of the flow theory of plastically compressible media formulas based on moisture-elasticity and plasticity model for strain analysis of dangerously hydrated loess ground are presented. For derivation of the constitutive equations of moisture transfer P. Ya. Polubarinova-Kochina's formula, Darcy's law for filtration rate and S.F. Averyanov to calculate the parameters at partial water saturation were considered. To estimate stress strain behaviour in subsiding building foundations, a finite element method and iterative methods are applied. The constitutive equation for plastic straining of dilating media is given. At each iterative step a linear problem is solved for soil ground with variable stress-strain properties that depend on a stress-strain state from the previous step. The parameters of matrix for stress-strain properties can be calculated during stabilometrical field tests or by processing the statistical relationship between strain and strength properties. The results of numerical studies and large-scale field tests, performed on experimental area of collapsible loess soil are compared. It is indicated that nonlinearly strained loess foundations of buildings must be regarded under partial saturation conditions, during dangerous hydration process and during stress field and humidity interaction in the course of moisture transfer.

Developing A Media ‘Visual Design of Pop Up Mathematics Book’ as a Supporting Tool in Inquiry-Based Learning for Learning Three-Dimensional Figures

Inquiry-based learning is one of the learning models that involves more students with the invention of concepts or formulas as its main goal. Inquiry learning can improve the students’ learning outcomes and learning quality. Inquiry learning steps include investigating problems, formulating hypotheses, designing experiments, analyzing data, and concluding. The main problem faced by the students when dealing with inquiry learning is to formulate the hypotheses and find the formulas. The objective of this research is to develop a media called Visual Design of Pop Up Mathematics Book to overcome the difficulty of inquiry learning on three-dimensional figures. This research is a media development research which is effective to support inquiry-based learning. The development processes carried out by the researcher through the selected development model include product analysis, the first product development, expert validation and revision, small-scale field test and product revision, large-scale field test and the final product. Subjects were 8th grade students of a state secondary school in Wonogiri district. Based on the small-scale test, students who were given the media of visual design of pop up mathematics book obtained better results. They were more able to guess the possible steps and find the right way or formula in solving the problem than the students who did not use the media.