Miracle-dz/UniFAR-FTUs huggingface dataset:
Elastic-Plastic Threshold and Rational Unloading Level of Rocks

During loading and unloading test, various rocks manifest different stress values of elastic-plastic transformation. This study proposes to include axial pressure increment ratio in the conventional triaxial compression test to evaluate different variables (nominal elastic modulus, nominal Poisson’s ratio, strain, and energy). The relationships among various factors including variables, the stress level of initial confining stress and axial pressures, were analyzed by analyzing the stress–strain plot record obtained from testing various rocks. The extreme value point of the deformation parameter, also known as the elastic-plastic threshold, was analyzed. In addition, the elastic-plastic thresholds were later used as unloading points during the unloading tests. Under the same confining condition, different rocks demonstrated different unloading levels. Furthermore, a linear correlation was observed between unloading levels and changing confining pressures, and the gradient is mainly related to the types of rocks. During the unloading tests of rocks, the rational unloading level is recommended to be no higher than the stress level at the elastic-plastic threshold under the corresponding confining pressure.
Chapter 12. Methods for Sterilization of Biopolymers for Biomedical Applications

Biopolymers have been found useful in biomedical applications because of their biocompatibility and degradability in the human body. Biopolymers can be formed naturally in living organisms and include polypeptides from proteins, polysaccharides from polymeric carbohydrates, and polynucleotides from nucleic acids – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Biopolymers can also be synthesized by using natural biological materials such as starch, sugars, fats, cellulose, and oils. Unsterilized biopolymers can cause severe infections in the human body when they are used for biomedical applications. Hence, biopolymers are required to undergo sterilization, which is a process to inactivate microorganisms including bacteria, spores, fungi, and viruses. The biopolymers that have been sterilized include both natural and synthetic biodegradable polymers such as chitosan, hyaluronic acid, polylactic acid, poly-l-lactic acid, and poly(lactide-co-glycolide), and are reviewed in this chapter. Sterilization methods that have been applied to biopolymers, including steam-autoclaving, dry heat sterilization, irradiation (gamma (γ)-rays, X-rays, ultraviolet, and electron beams), chemical treatment (ethylene oxide), gas plasma, and supercritical fluid sterilization, are reviewed.
Operating Assessment of Local Power Grid Development Considered Captive Power Plant and Expanding Structure

Based on current developments related to the application of technology and the growth of load demand, power system structure (PSS) has grown into a large, intelligent network by integrating many new systems. At present, many classical systems are being modernized and developed towards smart systems to various technical performances while providing continuously energy from the generating sites to serve load centres as end energy users. On the other hand, protection and attention to the environment and renewable energy sources also affect the power system operation which is intended to reduce emissions and include green energy sources. Furthermore, these works explore an assessment of operations on local interconnection system topologies which are installed captive power plants. These studies are used to develop and evaluate the performance, where solar power plants are also installed as sources of energy suppliers. In this study, operating assessments are approached using a power flow study (PFS) to define structural performance expanded through several scenarios. In addition, the procedure for obtaining optimal conditions is also facilitated by using the Takagi Method (TM) and Thunderstorm Algorithm (TA) for PFS hybrid structures considered an integrated renewable energy source (IRES). Based on the technical scenario set, the results show that the applied scenarios have different performances. In addition, this study also provides various implications. IRES has affected system performance. PSS contributes to the part that is committed to covering the burden. TM and TA can be applied to the hybrid PFS structure. Streszczenie. W artykule przedstawiono metodę PFS (power flow study) do optymalizacji struktury lokalnej sieci zasilającej z zainstalowanymi źródłami fotowoltaicznymi. Zastosowano też metodę Takagi i algorytm burzowy do optymalizacji sieci z różnymi scenariuszami. Analiza pracy lokalnej sieci z uwzględnieniem własnych źródeł energii i możliwości rozbudowy
Feature Engineering for Design Thinking Assessment

As design and design thinking become increasingly important competencies for a modern workforce, the burden of assessing these fuzzy skills creates a scalability bottleneck. Toward addressing this need, this paper presents an exploratory study into a scalable computational approach for design thinking assessment. In this study, student responses to a variety of contextualized design questions – gathered both before and after participation in a design thinking training course – are analyzed. Specifically, a variety of text features are engineered, tested, and interpreted within a design thinking framework in order to identify specific markers of design thinking skill acquisition. Key findings of this work include identification of text features that may enable scalable measurement of (1) user-centric language and (2) design thinking concept acquisition. These results contribute toward the creation of computational tools to ease the burden of providing feedback about design thinking skills to a wide audience.
Seismic behavior of strengthened square reinforced concrete columns under combined loadings

Abstract This paper presents an experimental study examining the seismic behavior of square reinforced concrete (RC) columns subjected to combined loadings. In this study, nine full-scale square RC columns were made with the same structural properties. Five of them were strengthened with high-performance ferrocement laminate and bonded steel plates in order to investigate the effects of strengthening on the seismic behavior of RC columns under combined loadings. Finally, the failure mode, hysteretic load-displacement response, bearing capacity, energy dissipation, ductility and plastic hinge characteristics were recorded and analyzed. The results show that combined loadings reduced the bearing capacity and changed the failure modes and deformation characteristics. Strengthened RC columns had significantly improved bearing capacity and different failure modes under the same combined loadings in contrast to the non-strengthened RC columns. The vertical eccentricity had little effect on the mechanical properties of columns, while the horizontal eccentricity significantly weakened the mechanical properties of columns. The mechanical properties of uniaxial compression-bending-shear-torsion columns were the worst. The tri-linear model calculation parameters under different failure modes and combined loadings were fixed and validated by experimental results.
Addressing Occupational Ergonomics Issues in Indonesian Forestry

This study addresses occupational ergonomics issues in Indonesian forestry (work conditions, workers' characteristics, occupational safety, occupational health, and job satisfaction) to acquire a comprehensive perspective in understanding the actual problems facing the operations. Direct observation, interview, questionnaires, and secondary data analyses were carried out to acquire all of the required information. A total of 191 frontline forestry workers (chainsaw operators, helpers, manual hauling workers, skidder/tractor operators, logging truck drivers, and nursery workers) participated in this study. The study shows that various techniques of forest operations (labor-intensive to semi-mechanized systems) have been applied in Indonesian plantation forests, both short and long-rotation, as well as in natural forest management. Most of the workers were non-permanent workers, who receive a low wage, work under a straight piecework system, have a high dependency on the forestry work to make a living, and exhibit poor comprehension of the concept of hazard control. The fatality rate was recorded as 1.3 deaths/106 m3 log, but this may be even higher as this rate only represents data taken from formal forestry workers. An intense physical dimension of fatigue occurs among workers involved in forest operations, with the highest prevalence of musculoskeletal disorders in the upper back, lower back, neck, shoulders, and arms. This study reveals eight variables that influenced job satisfaction, i.e., wage, type of contract, accessibility, health services, living facilities, work equipment, training, and social facilities.
Neural network temperature and moisture retrieval algorithm validation for AIRS/AMSU and CrIS/ATMS

We present comprehensive validation results for the recently introduced neural network technique for retrieving vertical profiles of atmospheric temperature and water vapor from spaceborne microwave and hyperspectral infrared sounding instruments. This technique is currently in operational use as the first guess for the NASA Atmospheric Infrared Sounder (AIRS) Science Team Version 6 retrieval algorithm. The validation incorporates a variety of data sources, independent from the algorithm training set, as ground truth, including global numerical weather analyses generated by the European Center for Medium‐Range Weather Forecasts, synoptic radiosonde measurements, and radiosondes dedicated for validation. The results demonstrate significant performance improvements over the previous AIRS/advanced microwave sounding unit (AMSU) operational sounding retrievals in both retrieval error and also show comparable vertical resolution. We also present initial neural network retrieval results using measurements from the Cross‐Track Infrared Sounder (CrIS) and Advanced Technology Microwave Sounder (ATMS) currently flying on the Suomi National Polar‐orbiting Partnership satellite.
FEEDER MODE CHOICE SELECTION BEHAVIOURAL MODELLING: THE CASE OF KTM KOMUTER, KUALA LUMPUR

Transit oriented development propagates the use of feeder services such as buses, taxis and paratransit to support the main rail trunks (Taylor, 1982; Limtanakool et.al, 2006; Alshalalfah & Shalaby, 2007). This paper attempts at explaining the preferences of passengers of a Malaysian rail service towards feeder buses, factors influencing their choices and recommendations to encourage the KTM Komuter passengers to switch mode to feeder services instead of driving theirprivate vehicles to and from stations. Using on-board intercept survey method, some results of 200 samples were analysed for the research. Findings showed that 76% of the passengers did not prefer to use the feeder. As such, the chi-square analysis did not find any socio-demographic factors such as gender, income, level of study, employment types, to be significant in explaining this mode switching behaviour. Some trip characteristics such as vehicle ownership, frequency andlength of using the KTM Komuter service also did not significantly influence the passengers' preference in using the feeder bus service. Other factors were then examined, including stationsâ€™ characteristics, usersâ€™ access and egress behaviours, travel time and distance. Therefore, in order to encourage the KTM Komuter users in using the feeder bus service, several recommendations such as providing an efficient, reliable frequency and catchment areas of feeder bus services were made.
Walking and talking sensors: conceptualising restorative leadership to enhance people management education in engineering

ABSTRACT The social dynamics interfering with engineering design expose engineers to workplace conflicts, undermining well-being and productivity. This strengthens the case for engineering management competences, and conflict management in particular. This conceptual study deepens understanding of industrial leadership by integrating prior knowledge of successful leadership and effective conflict management. Their parallel analysis shows that conflict management capacity is inherent in successful industrial leadership and that at their crossroads emerges a novel management mode, restorative leadership. It draws on two levels of personal capacity: (1) on the intrapersonal level, qualities promoting self-leadership help minimise the risk of relationship conflict and maximise the probability of constructive dispute resolution; (2) on the interpersonal level, clarity of communication and directness help prevent the risk of disputes and serve as instruments in conflict resolution. The findings are promising for higher engineering educators as the critical components of restorative leadership are learnable and teachable.
Entry Level Capability of Newly Qualified Science and Technology Teachers into the Teaching Profession

This study involved both instructional tool and learning tasks used for examining the entry level capability of newly qualified science and technology teachers (henceforth, NQSTTs). Utilizing a quasi-experimental design, the study included 106 NQSTTs, experimental group (N = 54) and control group (N = 52) exposed to a three-month professional qualifying examination (PQE) program. Instruments such as Science Achievement Test (SAT), Technology Achievement Test (TAT), Integrated Science, Technology and Society Test (ISTST) and Micro-teaching Practice were used to measure the NQSTTs’ entry level capability. All tests had versions of pretest and posttest and were administered to both groups at the start, and at the end of the study. Significant changes in teachers’ entry level capability were identified through repeated measures ANOVA tests run for each test at the significant level of . 05. Results indicated that teachers’ entry level capability relatively improved than expected, most probably as a result of the type of preparation they received. It is hoped that these findings may help to show interesting differences in programs aimed at preparing teachers for certification/induction. Didactic implications for science and technology education are discussed.
Design of a Novel Double Negative Metamaterial Absorber Atom for Ku and K Band Applications

This paper presents a multiband metamaterial (MM) absorber based on a novel spiral resonator with continuous, dual, and opposite P-shape. The full wave analysis shows 80.06% to 99.95% absorption at frequencies range for Ku and K bands for several substrate materials of 100 mm2 area. The results indicate that the absorption rate remains similar for different polarizing angles in TEM mode with different substrates. With FR4 (Flame Retardant 4) substrate and 64 mm2 ground plane, the design acts as single negative (SNG) MM absorber in K band resonance frequencies (19.75–21.37 GHz) and acts as double negative (DNG) absorber in Ku band resonance frequencies (15.28–17.07 GHz). However, for Rogers 3035 substrate and 36 mm2 ground plane, it acts as an SNG absorber for Ku band resonance frequency 14.64 GHz with 83.25% absorption and as a DNG absorber for K band frequencies (18.24–16.15 GHz) with 83.69% to 94.43% absorption. With Rogers 4300 substrate and 36 mm2 ground plane, it acts as an SNG absorber for Ku band at 15.04 GHz with 89.77% absorption and as DNG absorber for K band frequencies (22.17–26.88 GHz) with 92.87% to 93.72% absorption. The design was fabricated with all three substrates and showed quite similar results as simulation. In comparison with other broadband absorbers, this proposed MM absorber illustrated broad incidence angles in TEM mode.
Understanding the Acceptance and Use of M-Learning Apps by Entrepreneurs: An Application of the Social-Cognitive and Motivational Theories

This study is designed to examine factors influencing the acceptance of m-learning apps by entrepreneurs. The constructs used to develop the proposed model were drawn from the social cognitive and motivational theories. The model was validated using 218 valid responses from entrepreneurs in South Africa. The results showed that both intrinsic (i.e. perceived enjoyment) and extrinsic (i.e. perceived usefulness and social influence) motivational factors had a direct positive influence on the behavioral intentions to adopt m-learning apps. Also, perceived usefulness, which showed the strongest direct influence on behavioral intentions, was directly influenced by outcome expectancy, and indirectly influenced by self-efficacy. The study also evaluated the outcomes of use behavior. For one, entrepreneurs who used m-learning apps were more likely to recommend the m-learning apps to others. Moreover, use behavior was shown to have a significant positive influence on entrepreneurial self-efficacy.
Physical Strain, Exposure to Noise and Postural Assessment in Motor-Manual Felling of Willow Short Rotation Coppice

Biomass for energy production and other bioproducts may be procured from various sources including willow short-rotation coppice (WSRC). Management of WSRCs involves several operations, including harvesting, which accounts for the greatest cost share and, if conducted motor-manually, it can expose the workers to noise, uncomfortable work postures and high cardiovascular loads. In this study, we evaluated the productivity, physical strain, exposure to noise, and postural risk index of workers operating in motor-manual felling of WSRC using a set of automatic dataloggers. Productivity of felling operations was rated at 0.07 ha/h, which is in line with the results reported by other studies. Cardiovascular load was rated at cca. 35% of the HRR, indicating a medium to heavy work experienced by the feller, with a greater contribution of tasks involving movement. Exposure to noise (LEX,8h = 95.19) exceeded the limit value set by the European legislation (87 dBA) and it could increase as a function of the engine utilization rate, which was 68% in this study, advocating for mandatory wearing of protective equipment. Postural risk index was evaluated at 191.11% for the worker handling the brush cutter and at 192.02% for the manual assistant indicating rather reduced risks, but also the need to evaluate how the dynamic work of the upper limbs would affect the workers’ health. While this work stands for a preliminary case study, the procedures described may be successfully used to easily collect long-term data in such operations.
Building–Soil Thermal Interaction: A Case Study

This paper presents an analysis of thermal interaction between a building and surrounding soil. The examined building was located in southern Poland. Measurements of selected indoor and outdoor air temperature parameters were made in order to determine the boundary conditions. The soil temperature measurements were conducted at 42 points. The analysis of results is divided into four periods: summer, autumn, winter, and spring. The analysis show that weather conditions significantly affect the temperature in soil, but the range of residential building impact decreases with distance, and it varies depending on the season. The residential building impact on the soil temperature is in the range of 1.2–3.3 m. This paper also includes a study of the heat flow direction in soil and a quantitative estimate of heat exchange between a building and the soil. The greatest energy losses 2082 kWh (21.24 kWh/m2) from the building to the soil were recorded in winter. In spring, the energy losses were reduced by about 38% as compared with the energy losses in winter, and the energy losses in spring were comparable to autumn.
Charged charmoniumlike structures in the $e^+ e^- \to \psi(3686) \pi^+ \pi^-$ process based on the ISPE mechanism

In 2017, the BESIII Collaboration announced the observation of a charged charmonium-like structure in the $\psi(3686)\pi^\pm$ invariant mass spectrum of the $e^+ e^- \to \psi(3686) \pi^+ \pi^-$ process at different energy points, which enables us to perform a precise study of this process based on the initial single pion emission (ISPE) mechanism. In this work, we perform a combined fit to the experimental data of the cross section of $e^+ e^- \to \psi(3686) \pi^+ \pi^-$, and the corresponding $\psi(3686)\pi^\pm$ and dipion invariant mass spectra. Our result shows that the observed charged charmonium-like structure in $e^+ e^- \to \psi(3686) \pi^+ \pi^-$ can be well reproduced based on the ISPE mechanism, and that the corresponding dipion invariant mass spectrum and cross section can be depicted with the same parameters. In fact, it provides strong evidence that the ISPE mechanism can be an underlying mechanism resulting in such novel a phenomenon.
A Cooperative Method to Improve Segmentation of Brain MR Images

In this paper, we present a fully unsupervised segmentation process of magnetic resonance image (MRI) of the brain using a data fusion technique and some of ideas of the possibility theory context. The fusion methodology is decomposed into three fundamental phases. We modeling information coming from T2 and PD weighted images in a common framework, in this step an hybridization between FCM and PCM algorithms is retained. In the second phase an operator of fusion is used to combine then this information. Finally, an image of fusion is generated when a decision rule is applied. Some results are presented and discussed using a set of simulated MR image
Interruption of Low-Voltage DC Arc in Air Under Axial Magnetic Field

This paper represents the findings from our research in which a series of experiments were conducted on dc current interruption in air in axial magnetic field provided from rare earth magnets mounted in the test electrodes. The experimental range was as follows: arc voltage 80–100 V, arc length 5–10 mm, arc current 80–800 A, and applied field 35–2400 G. The free-burning arc diameter was measured in these experiments from high-speed photographs. It was found that a strong magnetic field can improve the interruption capacity of air-arc significantly. In the experiments, the successful switching time of both 220 and 330 A free-burning air-arc in 2.4 kG was less than half of the successful switching time of corresponding free-burning arcs in air. For higher current arcs, the outcome was more encouraging. An 800 A free-burning arc sustained for about 48 ms, whereas a 315 G field interrupted it within 8 ms. The information found on arc-root diameter and current density of 80–800 A free-burning arcs in air has filled a gap of data found in the literature. This information, in turn, will help to improve the theories available on free-burning arcs.
DLFCR Reduction Based on Power Predictive Scheme for Full-Bridge Photovoltaic Microinverter

This article proposes a double-line-frequency current ripple (DLFCR) reduction strategy for the photovoltaic microinverter. A power predictive scheme is established according to the output power mathematical model of the prestage full-bridge dc–dc converter (PFDDC), which is the basis of the proposed DLFCR reduction strategy. The control effect is analyzed with considering parameter estimation error, and the analysis results show that the proposed strategy has good dynamic performance and robust performance. The small-signal model of the PFDDC has been established to design the voltage-loop parameters. The bandwidth of the system controlled by the power predictive scheme is large, which can effectively reduce the design complexity because no parameter is needed to design for power prediction. Experimental verifications are presented to verify the analysis.