Multistage Test Research Articles

BARIK: laboratory programme within the framework of the development of an extended Hoek–Brown-based anisotropic constitutive model for fractured crystalline rock

Abstract. The disposal of heat-generating radioactive waste in deep geologic formations is a global concern. Numerical methods play a key role in understanding and assessing the disposal scenarios of radioactive waste in deep geological repositories. However, the complexities of the thermal, hydrological, mechanical, chemical, and biological processes associated with the disposal of radioactive waste in porous and fractured materials constitute significant challenges. One of the most challenging issues in this field is the complex material behaviour of fractured crystalline rock. The presence of fractures makes the rock anisotropic, nonlinear, and dependent on loading paths. Additionally, the Biot coefficient cannot be considered constant throughout the critical and subcritical fracture development regions. These factors make the development of an accurate constitutive model for fractured crystalline hard rock a critical component of any deep geological disposal project. Furthermore, to demonstrate the integrity of the “containment effective rock area” in crystalline host rock, the qualitative integrity criteria must be quantified so that numerical simulation can be performed with concrete numerical values. Part of this assessment for a crystalline host rock is a dilatancy criterion, which is currently based on the Hoek–Brown constitutive model. This contribution provides an overview and first results of the laboratory programme, which was performed as a part of the research project. The aim was to generate a fundamental and extensive dataset for an anisotropic material used for verification and validation purposes of the newly developed constitutive model. The rock material for the test programme was “Freiberger gneiss” because of its pronounced anisotropic properties regarding deformation and strength as well as the good access to obtain a larger amount of sample material. A wide range of basic tests have been performed, e.g. determination of density and porosity, measurement of ultrasonic wave velocities to get dynamic elastic properties, Brazilian tests, and uniaxial compression tests to obtain strength data. Additionally, a large number of more complex multi-stage triaxial compression tests with examination of the post-failure region and hydromechanical coupled triaxial compression tests have been conducted or are in progress. The hydromechanical part, in particular, plays an important role in examining and quantifying the evolution of the micromechanical damage process, which changes the permeability and Biot coefficient and therefore the effective stresses inside a saturated rock material. Tests were conducted with different orientations of the structural planes in relation to the loading directions.

Profil Kondisi Fisik Atlet Bola Voli STKIP PGRI Pacitan

Study purpose. The aim of the study was to determine the physical condition profile of STKIP PGRI Pacitan Bola voli athletes who competed in the East Java POMPROV championship in 2023. The athlete's physical condition used as a benchmark to determine whether the athlete was ready before competing. Materials and methods. The study used a survey description method with test and measurement techniques. The research population used was all STKIP PGRI Pacitan indoor volleyball athletes who competed in the East Java POMPROV Championship in 2023. The measuring instruments: sit-up test, sit and reach test, vertical jump test, 20 m run test, and multi-stage fitness test. The data analysis technique used a Likert scale. Result. The results of data analysis in this study as a whole show that 0% of athletes had a physical profile in the very good category, 85.72% (12 athletes) had a physical profile in the good category, 7.14% (1 athlete) had a physical profile in the moderate category, 7.14% (1 athlete) had a physical profile in the less category, and 0% had a physical profile in the very poor category. Conclusions. The conclusion of the study is that the physical condition of STKIP PGRI Pacitan volleyball athletes who would take part in the POMPROV Championship in 2023 East Java as a whole was in a good category so that athletes were declared physically ready to take part in the championship.

HUBUNGAN BENTUK TELAPAK KAKI FLAT FEET DENGAN VO2 MAKS PADA ATLET PENCAK SILAT TINGKAT PROVINSI DKI JAKARTA BERDASARKAN LAMA LATIHAN

Flat feet can cause a reduction in the foot function resulting in fatigue when walking or running. This condition can result in a suboptimal intensity exercise required to improve VO2Max of Pencak Silat athletes. This study aimed to determine the relationship between the shape of foot and VO2Max based on training duration among Pencak Silat athletes at the provincial level of DKI Jakarta. The study used a cross-sectional design involving 46 athletes selected through a total sampling. The subject criteria for this study included athletes aged 17-24 years, healthy, and had no lower extremities problems. The study utilized footprint test and multistage fitness test instruments. The study found that 27 (58.7%) athletes had a normal foot shape, while 19 (41.3%) had flat feet. There were no differences in age, sex, body mass index, and training duration between the two groups of foot shape (p 0.05). The maximum VO2 value was 45.0 (7.2) ml/kg/min in athletes with normal foot shape and 40.1 (70.5) ml/kg/min in athletes with flat feet. The independent t-test revealed a significant difference in VO2Max between the two groups of foot shapes (p = 0.028). The increase of VO2Max was in line with the duration of exercise, but this increase was not significant in subjects with flat feet compared to those with normal foot shape. It concludes that flat feet are negatively associated with VO2Max of athletes. Pencak Silat athletes with flat feet must exert extra effort to enhance their VO2Max, such as interval training and kinesio taping. Further research is recommended to explore the impact of these efforts on improving VO2Max.

Application of a Multi-Stage Testing and Evaluation Approach for a Safety-Related Digital Upgrade at a Nuclear Power Plant

There is an imminent need for existing United States nuclear power plants to reduce their operating and maintenance costs to remain economically viable. Digital technology provides significant opportunity for the existing nuclear power plant fleet to transform that way in which work is accomplished to reduce costs and allow the fleet to remain economically competitive. However, a careful understanding of the human-technology integration is needed to ensure the continued safe and reliable operation of these existing plants with new digital capabilities. This work presents interim findings in applying human factors engineering to a safety-significant digital upgrade for a United States nuclear power plant, following the new Alternative Review Process in the recently revised Digital Instrumentation and Control Interim Staff Guidance Licensing Process, Revision 2. The interim results described in this work provides an industry perspective, based on ongoing work, to support recent work published from Vazquez, Green, and Desaulniers (2022).

How to identify norms, laws, and regulations that facilitate illicit financial flows and related financial crimes

PurposeIllicit financial flows are targeted by the United Nations’ (UN) sustainable development goals (SDGs). However, these illicit flows are not entirely understood. Furthermore, they can benefit from economic norms, laws and regulations that lack mechanisms to detect and penalize them. This paper aims to investigate whether a recent test, the embezzler test, can be used to identify regulatory architectures that facilitate illicit financial flows and related financial crimes.Design/methodology/approachThis paper develops a more advanced version of the embezzler test in terms of definitions and practical implementation methodology.FindingsIn this test, the definition of embezzlement can be understood to be the occurrence of illicit financial flows crossing the boundaries of organizations and/or countries. This is a multistage test, which intentionally simulates illicit financial flows to observe how well equipped is the regulatory architecture to deal with other financial offences that are related with these flows, such as theft, money laundering, fraud, corruption, market manipulation and tax evasion.Research limitations/implicationsFuture research can use the version of this test to stress test a large range of economic norms, laws and regulations.Social implicationsThis test’s new version can assist achieve the UN SDGs’ illicit financial flow reduction target. Furthermore, it can be used to study both existing and proposed norms, laws and regulation.Originality/valueTo the best of the author’s knowledge, this is the first explicit test that has been presented to identify norms, laws and regulations that facilitate illicit financial flows and related financial crimes.

The effect of training methods and lung vital capacity on vo2max in student futsal athletes

This study investigates the effect of extensive, intensive interval training methods and the vital lung capacity of futsal athlete students to improve the vo2max. This type of research was quasi-experimental with a 2x2 factorial design. 24 male student futsal athletes, age 15.95±0.55, height 164.61±6.90, and weight 53.23±8.11, met the inclusion criteria, signed informed consent and participated in this study. The interventions were extensive interval training methods for running on a 20-meter track and intensive interval training for running on a 100-meter track. Treatment is done 16 times, three times a week, and progressive sets, repetitions, time, and rest. Vo2max was measured with a multistage fitness test, and lung vital capacity was measured with spirometry SP70B. Data analysis used two-way ANOVA, the data was tested for normality and homogeneity. The study showed that extensive pretest 37,53±1,37 and posttest 50,68±1,00 (p=0.05), and intensive pretest 37,04±1,45 and posttest 49,18±1,37 (p=0.05) interval training improves VO2Max, repestivully. There is no interaction between extensive and intensive training methods on lung vital capacity. The study concludes that extensive and intensive training methods are useful to improve the vo2max of students' futsal athletes. The extensive interval training method is more effective in improving vo2max.

Effect of Circuit and Interval Training Methods on the Agility and VO₂max of Porprov Football Players in Pati Regency in Terms of Leg Muscle Endurance

This study aimed to determine: (1) the effect of circuit and interval training methods on agility and VO₂max; (2) the difference in the effect of high leg muscle endurance and low leg muscle endurance on agility and VO₂max; (3) the interaction between circuit training, interval training and leg muscle endurance (high and low) on agility and VO₂max. Materials and methods. This research is an experiment with a 2x2 factorial design. In this study, the number of samples used was 20 players selected by purposive sampling. Agility was measured with the Illinois agility test instrument, VO₂max was measured with a multistage fitness test, and leg muscle endurance was measured with a wall sit test. Data analysis used a two-way ANOVA test with a significance level of α < 0.05. Results. The results of this study are as follows: (1) there is no difference in the effect of the circuit and interval training methods on the agility of football players, there are significant differences between the circuit and interval training methods in their effect on the VO₂max of football players; (2) there is a difference between high and low leg muscle endurance for agility and VO₂max, α < 0.05; (3) there is an interaction between the circuit, interval training, and leg muscle endurance (high and low) on agility, α < 0.05. Conclusions. There is an interaction between circuit training, interval training, and leg muscle endurance (high and low) on the agility of Porprov soccer players in Pati Regency. Meanwhile, there was no interaction between circuit training, interval training, and leg muscle endurance (high and low) on the VO₂max of Porprov football players in Pati Regency.

The relationship between social support and happiness in older adults referred to health centers in Zarrin Shahr, Iran

Background: Creasing the older adult population has become a major public health challenge. Social support plays an important role in people's health. Social support helps improve the living conditions of the elderly and brings happiness into the lives of the elderly. This study aimed to investigate the relationship between social support and happiness status in 60–75-year-olds referred to health centers of Zarrin Shahr, Iran in 2019.Methods: In this cross-sectional study, 584 samples (female: 62.2%, men: 37.8%) participated in this study. To collect data for this study, Oxford Happiness, and Social Support questionnaires were used. The older adults of the target group were selected through simple multistage random sampling from the health centers of Zarrin Shahr. The collected data were entered into SPSS software version 22. They were described and analyzed by inferential statistics and regressions at a 95% confidence level.Results: Sex, marital status, and level of education influenced total social support (P < 0.05). Moreover, age, marital status, and level of education affected happiness (P < 0.05). There was a significant positive correlation between total social support and components of social support with happiness (P < 0.05). Also, the multi-stage regression test showed emotional social support and education level were highly correlated with happiness (R2 = 0.265).Conclusion: The results highlight the need to increase social support for older adults because it can increase the level of happiness in this age group. In interventions to improve the social support and happiness of older adults, low-educated, unmarried, divorced, or deceased spouses should be prioritized.

Effects of consolidation conditions on the dynamic shear modulus of saturated coral sand over a wide strain range

The utilization of coral sand as a construction material for ports and other infrastructure systems in coral reefs is prevalent, wherein the soil elements within slopes and embankments typically experience an anisotropic stress state. It is imperative to accurately characterize the degradation behavior of the stratigraphic material's stiffness across a wide range of strains. In this study, the maximum and strain-dependent shear modulus (G0 and G) characteristics of saturated coral sand under isotropic and anisotropic consolidations were investigated by performing multi-stage stress-controlled undrained cyclic torsional shear tests with cyclic hollow cylinder shear apparatus. The experimental results indicated that G0 and G generally rose with increasing initial effective consolidation pressure but decreased with increasing inclination of initial major principal stress from the vertical (αc). In contrast, the effect of consolidation stress ratio (kc) on G0 and G was nonmonotonic, and that of kc and αc on the strain-dependent shear modulus reduction (G/G0) curve was slight. By defining anisotropic consolidation indexes δ0 and δr used for quantifying the effect of consolidation-induced anisotropy on the G0 and the G/G0, respectively. A unified formula of G0 obtained by multiplying Hardin's model by δ0, as well as a unique formula of G/G0 obtained by correcting γr in the Davidenkov skeleton curve expression as a linear function of δr were established under various consolidation conditions, respectively. The proposed G formula over a wide strain range is well validated by the experimental data for siliceous sandy soils from the literature.

Creep and ageing of granular materials under isotropic pressure

Single- and multi-stage isotropic creep tests including bender element and acoustic emission measurements are carried out to investigate the relationship between ageing and creep in dense silica sand. In the considered pressure range, the experimental results show an inversely proportional relationship between ageing and creep: the small-strain shear modulus increases with decreasing isotropic pressure,, while the axial creep strain and the acoustic emissions show the opposite pressure dependence. In the multi-stage creep test, the small-strain shear modulus increases monotonically, while the rates of axial strain, number of acoustic emissions and small-strain shear modulus decrease with time according to a power law. In the single-stage creep tests, the ageing and creep indicators initially evolve as in the multi-stage creep test, but then the small-strain shear modulus reaches a peak value and decreases with time thereafter. At the same time, the rates of axial strain, number of acoustic emissions and small-strain shear modulus deviate from the power law. A conceptual model assuming a time-dependent behaviour of the normal and shear forces at the particle contacts in order to explain the experimental observations qualitatively is proposed. Accordingly, an increase in small-strain shear modulus results from homogenisation of the force chains, while a decrease in small-strain shear modulus results from a temporary formation followed by a time-delayed collapse of strong force chains.

Process Setup and Boundaries of Wire Electron Beam Additive Manufacturing of High-Strength Aluminum Bronze

In recent years, in addition to the commonly known wire-based processes of Directed Energy Deposition using lasers, a process variant using the electron beam has also developed to industrial market maturity. The process variant offers particular potential for processing highly conductive, reflective or oxidation-prone materials. However, for industrial usage, there is a lack of comprehensive data on performance, limitations and possible applications. The present study bridges the gap using the example of the high-strength aluminum bronze CuAl8Ni6. Multi-stage test welds are used to determine the limitations of the process and to draw conclusions about the suitability of the parameters for additive manufacturing. For this purpose, optimal ranges for energy input, possible welding speeds and the scalability of the process were investigated. Finally, additive test specimens in the form of cylinders and walls are produced, and the hardness profile, microstructure and mechanical properties are investigated. It is found that the material CuAl8Ni6 can be well processed using wire electron beam additive manufacturing. The microstructure is similar to a cast structure, the hardness profile over the height of the specimens is constant, and the tensile strength and elongation at fracture values achieved the specification of the raw material.

Sequential Bayesian assurance tests for degradation data

Measuring degradation of items in a reliability context may be all that is feasible. There may simply be neither enough time nor resources to produce a sufficient number of item failures to characterize the underlying time-until-failure distribution. In such contexts, degradation data-based assurance testing can be tuned to strike a compromise between consumer and producer risk when deciding whether to accept or reject a product. A one-stage assurance test counts the number of items in a sample exceeding a fixed degradation threshold at a fixed time and uses this count to make the decision: accept or reject. A general Bayesian framework for extending assurance testing from one-stage to a multi-stage or sequential setting is presented. Our multi-stage assurance tests are shown to compare favorably to their one-stage counterparts by possessing a lower expected time requirement at given sample size and risk constraints. Examples of the methods based on a printhead application are provided and are reproducible with the supplemental R code.

Comparing the reliability of muscle oxygen saturation with common performance and physiological markers across cycling exercise intensity.

Wearable near-infrared spectroscopy (NIRS) measurements of muscle oxygen saturation (SmO2) demonstrated good test-retest reliability at rest. We hypothesized SmO2 measured with the Moxy monitor at the vastus lateralis (VL) would demonstrate good reliability across intensities. For relative reliability, SmO2 will be lower than volume of oxygen consumption (V̇O2) and heart rate (HR), higher than concentration of blood lactate accumulation ([BLa]) and rating of perceived exertion (RPE). We aimed to estimate the reliability of SmO2 and common physiological measures across exercise intensities, as well as to quantify within-participant agreement between sessions. Twenty-one trained cyclists completed two trials of an incremental multi-stage cycling test with 5 min constant workload steps starting at 1.0 watt per kg bodyweight (W·kg-1) and increasing by 0.5 W kg-1 per step, separated by 1 min passive recovery intervals until maximal task tolerance. SmO2, HR, V̇O2, [BLa], and RPE were recorded for each stage. Continuous measures were averaged over the final 60 s of each stage. Relative reliability at the lowest, median, and highest work stages was quantified as intraclass correlation coefficient (ICC). Absolute reliability and within-subject agreement were quantified as standard error of the measurement (SEM) and minimum detectable change (MDC). Comparisons between trials showed no significant differences within each exercise intensity for all outcome variables. ICC for SmO2 was 0.81-0.90 across exercise intensity. ICC for HR, V̇O2, [BLa], and RPE were 0.87-0.92, 0.73-0.97, 0.44-0.74, 0.29-0.70, respectively. SEM (95% CI) for SmO2 was 5 (3-7), 6 (4-9), and 7 (5-10)%, and MDC was 12%, 16%, and 18%. Our results demonstrate good-to-excellent test-retest reliability for SmO2 across intensity during an incremental multi-stage cycling test. V̇O2 and HR had excellent reliability, higher than SmO2. [BLa] and RPE had lower reliability than SmO2. Muscle oxygen saturation measured by wearable NIRS was found to have similar reliability to V̇O2 and HR, and higher than [BLa] and RPE across exercise intensity, suggesting that it is appropriate for everyday use as a non-invasive method of monitoring internal load alongside other metrics.

Comprehensive numerical modeling of gas storage in Firouzabad salt dome based on multistage creep test and operational parameters

Comprehensive numerical modeling of gas storage in Firouzabad salt dome based on multistage creep test and operational parameters

EFFECT OF 6 WEEKS OF CIRCUIT TRAINING ON INCREASED VO2 MAX

This study aimed to analyze the effect of 6 weeks of Circuit Exercise on increasing VO2max. The research design applied to this study used pre-experimental with one group pretest and posttest design. The number of subjects of this study was 24 Opel Futsal Club U-16 athletes in Lamongan Regency. The treatment in the study was in the form of circuit training, carried out as many as 18 meetings for 6 weeks with a frequency of exercise 3 times a week. The test instrument used in this study was a multistage fitness test. Technical analysis uses a t-test with the prerequisites of a normality test. The results of the study found that the VO2max mean pretest value was 39.29 ml / kg / minute and for the posttest mean results was 43.93 ml / kg / minute. The results of paired sample t-test analysis are 0.000 &lt; 0.05. Based on the results of the analysis, it can be concluded that 6 weeks of circuit training can increase VO2max significantly.

Element distribution in electrochemically treated mine wastewater for efficient resource recovery and water treatment: A pilot study

The feasibility of recovering major and critical elements from acid mine drainage using a pilot-scale electrochemical reactor (ECR) was investigated by assessing elements concentration and species distribution in the liquid and solid phase (sludge) in multistage tests. These were carried out at different electrical currents (18–22 amps) and thus, pH (8–12). The results showed that major metals Al, Cu and Fe were removed from the liquid phase at pH 5.9 while remaining the majority of Zn (57.2 ppm). On the other hand, at pH 7, the effluent was mainly composed of Mn (7.3 ppm). These results were confirmed by the simulation results using the PHREEQC model, which also identified the main chemical species in solution and the precipitates formed after the treatment (oxyhydroxides/sulfates/oxides). The ECR treatment led to sludges with targeted critical elements, some up to 20 times (Co, Be and Sb) higher than their earth's crustal abundance. At pH 10, rare earth elements in the sludge targeted Ce, followed by Nd and La. This study is one of the few studies carrying a detailed analysis of the behavioural distribution pattern of these elements at each pH, which opens the door for the potential of recovering these elements.

Production quality prediction of multistage manufacturing systems using multi-task joint deep learning

A multistage manufacturing system with multiple manufacturing stages is the key and main production mode for enterprises to achieve lean production. Due to the variation propagation between stages and multiple related quality prediction tasks, it is difficult to accurately predict the quality of multistage manufacturing systems with multiple tasks. Traditional single stage and single task quality prediction methods permit the multi stages and multiple tasks separately, which ignore multi-stage effects or the quality-related relationship between multiple quality output indicators and reduce the efficiency of quality prediction. In this paper, a production quality prediction framework based on multi-task joint deep learning is proposed to simultaneously evaluate the multi-task quality of all stages in a multistage manufacturing system. To be specific, variation propagation cumulative impact between multiple manufacturing stages is innovatively expressed by designing a multi-scale convolutional neural network with control gates (MCNN-CG) to extract and propagate data features. Production quality with multi-tasks at all stages is jointly predicted by designing a multi-layer multi-gate mixture-of-experts multi-task (ML-MMoE) model with reducing multi-task predictive loss simultaneously. The soft parameter-sharing strategy and multi-gate attention strategy are separately designed to ensure information sharing while learning personalized features of tasks to improve quality prediction accuracy of each task. In addition, a loss function based on homoscedastic uncertainty and regularization is designed to automatically learn the weight between multi-stage and multi-task losses. Experiments on multistage assembly test data of an inertial navigation manufacturing system show that the proposed method performs better than traditional models. Compared to the single-stage model, the proposed multistage model has an average improvement of 8.5%, 20.0% and 23.3% in R2, MAE and RMSE respectively in the second stage. Compared with the traditional multi-stage model, the proposed model has an average improvement of 1.7%, 6.2% and 9.8% in R2, MAE and RMSE respectively in the second stage.

Nonlinear elastic constitutive model of clayey sand reservoirs during depressurization exploitation of natural gas hydrate

Accurate evaluation of the mechanical response of hydrate-bearing reservoirs is a prerequisite for safe and efficient exploitation of natural gas hydrate resources. Therefore, it is necessary to develop a suitable constitutive model and to determine reasonable model parameters for hydrate-bearing sediments (HBSs) during exploitation. In this study, based on the strain-hardening behavior of clayey sand reservoirs published in the previous study, Duncan–Chang model was used as the basic model to establish constitutive models for HBSs during exploitation. The model parameters, initial elastic modulus and ultimate deviatoric stress, were determined by modifying existing formulas and establishing empirical formulas. Four nonlinear elastic constitutive models were proposed by combining the model parameters determined by different methods. Multi-stage and single-stage triaxial test data were used to verify the applicability of the model and determine the optimal model suitable for the sediments under study.

EVALUATION OF TEACHER ASSESSMENT CAPABILITIES THROUGH MULTI-STAGE ADAPTIVE TESTING

The objective of this study is to assess MSAT (MULTI-STAGE ADAPTIVE TEST) performance of 21 Teachers and was carried out at Madrasah Ibtidaiyah Negeri 9 Nagan Raya, with the research subjects being Madrasah teachers and performed with three cycle tests. In accordance with the assessment results, the average score increased from pre-cycle to cycle I to cycle II, where the pre-cycle observation average score only reached 6.4 while in cycle I it reached 11.4, indicating that the teacher's ability to the assessment process using the multi-stage adaptive testing (MSAT) application is good. Cycle II then received a score of 15.8, indicating that the teacher's proficiency in the assessment process utilizing the multi-stage adaptive testing (MSAT) application was excellent.

Analisis kondisi vo2max pemain hoki indoor putri Gresik dalam menunjang keberhasilan meraih medali emas

The VO₂Max condition of the Gresik women's indoor hockey players should be fulfilled. Since VO₂Max includes a baseline that represents general fitness which is good condition VO₂Max it can be assumed other physical endurance will follow. The purpose of this study was to find out the level of aerobic endurance (VO₂Max) possessed by Gresik women's indoor hockey players in supporting the success of winning a gold medal at Situbondo in 2022. Quantitative descriptive was used in this research method with 12 research subjects. The multi-stage fitness test (MFT) was used as an instrument in this study. The results of the analysis of aerobic endurance (VO₂Max) data from female indoor hockey players in the category "very poor" 0.00% (0 players), "less" 0.00% (0 players), "enough" 0.00% (0 players), “good” 50.00% (6 players), “very good” 41.70% (5 players) and “excellent” 8.30% (1 player). The average of this data analysis was 39.34. Based on these results, the level of aerobic endurance (VO₂Max) of Gresik women's indoor hockey players was in the “very good” category. It can be concluded that to meet good VO₂Max conditions, the results of this study can be used as a benchmark for other hockey teams when preparing for matches.