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Because of the crucial importance of finding a useful biomarker for further clinical trials in Machado-Joseph disease (MJD), and based on our previous studies, we aimed to evaluate whether the horizontal vestibulo-ocular reflex (VOR) gain could be a reliable neurophysiological biomarker for the clinical onset, severity, and progression of the disease. Thirty-five MJD patients, 11 pre-symptomatic genetically confirmed MJD subjects, and 20 healthy controls underwent a detailed epidemiological and clinical neurological examination including the Scale for the Assessment and Rating of Ataxia (SARA). Their VOR gain was measured using the video Head Impulse Test system. Twenty of the MJD patients were re-tested after a period of 1–3 years. Horizontal VOR gain was abnormal in 92% of MJD, 54% pre-symptomatic, and 0% healthy controls. Horizontal VOR gain in the MJD group was significantly negatively correlated with SARA score in the first (r=0.66, p<0.001) and second (r=0.61, p<0.001) examinations. There was also a significant negative correlation between the percentage of change in horizontal VOR gain and the percentage of change in SARA score across both examinations (r=−0.54, p < 0.05). A regression model of the SARA score with the horizontal VOR gain and disease duration as predictors demonstrated that both the horizontal VOR gain and the disease duration had an independent contribution to the prediction of the SARA score. The horizontal VOR gain seems to be a reliable biomarker for the clinical onset, severity, and progression of MJD and could be used in further clinical studies. [ABSTRACT FROM AUTHOR]

In the second half of the 20th century, neuroscientists across North America developed automated systems for use in their research laboratories. Their decisions to do so were complex and contingent, partly a result of global reasons, such as the need to increase efficiency and flexibility, and partly a result of local reasons, such as the need to amend perceived biases of earlier research methodologies. Automated methods were advancements but raised several challenges. Transferring a system from one location to another required that certain components of the system be standardized, such as the hardware, software, and programming language. This proved difficult as commercial manufacturers lacked incentives to create standardized products for the few neuroscientists working towards automation. Additionally, investing in automated systems required massive amounts of time, labor, funding, and computer expertise. Moreover, neuroscientists did not agree on the value of automation. My brief history investigates Karl Pribram's decisions to expand his newly created automated system by standardizing equipment, programming, and protocols. Although he was an eminent Stanford neuroscientist with strong institutional support and computer know-how, the development and transfer of his automated behavioral testing system was riddled with challenges. For Pribram and neuroscience more generally, automation was not so automatic. [ABSTRACT FROM AUTHOR]

In this work, 3‐(pyrimidin‐2‐ylthio)phthalonitrile (n‐MP1), non‐peripherally 3‐(pyrimidin‐2‐ylthio) groups substituted Zn (II) phthalocyanine (n‐MP2), and its water soluble derivative (n‐MP3) have been firstly synthesized and characterized with spectral data. The interaction of the n‐MP3 complex with DNA was examined in vitro using UV–visible titrimetric and thermal denaturation assays and in silico by performing molecular docking studies. In addition, the antidiabetic activity of n‐MP3 was revealed spectroscopically by studying α‐glucosidase inhibition activities. The spectroscopic results indicated that n‐MP3 effectively binds to CT‐DNA with a Kb value of 2.0 × 105 M−1 and interacts with CT‐DNA via noncovalent binding mode. Besides, docking studies divulged that n‐MP3 exhibits a stronger binding tendency (BE: −10.64 kcal/mol) with DNA than the control compounds, (7.78 kcal/mol for ethidium bromide and −6.21 kcal/mol for cisplatin). Consequently, due to its strong DNA binding activity, n‐MP3 may be suitable for antimicrobial and anticancer applications after further toxicological test systems. Also, n‐MP3 complex inhibited the activity of α‐glucosidase with the IC50 value of 1.44 ± 0.08 μM, whereas IC50 value of acarbose was 237.24 ± 1.80 μM. Therefore, it can be said that n‐MP3 is a very effective α‐glucosidase inhibitor. [ABSTRACT FROM AUTHOR]

Chips must be reliably segmented and evacuated from the cutting zone for effective deep hole drilling. Drilling with low-frequency axial vibrations ensures these useful effects because cutting edges periodically leave the cutting zone. Useful tool vibrations can be maintained using a special self-vibratory drilling head. The drilling head has an elastic element and ensures the self-excitation of vibrations due to the regenerative effect. However, high damping in the cutting zone suppresses axial self-vibrations and renders such a drilling head inexpedient for industry. This study develops a novel system of adaptive control for the vibration drilling process. The control objective is to maintain a specified peak-to-peak (PTP) value of vibration displacements. Due to the in-process adaptation of the feedback gain, the control system supplies additional energy if vibrations are not self-excited and removes energy if the PTP vibration displacements are greater than the specified value. To test the workability of the system, an experimental setup was made. In the setup, the actuator force acts on an elastically fixed workpiece. The dynamic properties of the setup are equivalent to those of the vibration drilling head. The algorithm of feedback gain adaptation was implemented with a microcontroller. A number of experiments for different drilling regimes revealed that the control system successfully maintains the specified PTP value of displacements. The developed control system can be implemented on a vibration drilling head because only an accelerometer is required for control and the required actuator force is under 100 N. [ABSTRACT FROM AUTHOR]

Minimization of power losses in distribution network (DN) is one of the vast areas of research, where researchers are performing different techniques and methods to reduce the losses. In recent times, network reconfiguration (Nr) has gained more significance in DN to reduce the losses due to its ease of implementation. Most of the work carried on Nr has usually assumed only single hour load model, which didn't vary with time. But in practical DN, load varies during the day. The tie line switching configuration obtained with single hour load model (which doesn't vary with time) is implemented in practical DN, it induces high power losses, reduces the reliability, loadability and voltage profile of the network. Most of the researchers have used single hour load model with Nr and not considered variation in load with Nr. In this study, variation in load is considered with twenty-four hour load. An investigation has been performed to find the losses obtained with variation in load for twenty-four hours. However, changing the topological of the network without disturbing the radiality is a complex non differentiable optimization problem. Nr implemented with twenty-four hour load has more complex computation as compared with single hour load. A quantum-inspired evolutionary algorithm, i.e., adaptive quantum-inspired evolutionary algorithm (AQiEA), is used to solve this complex optimization problem. In this study, two test cases are created in which the first case, uses four different scenarios to find the effect of power losses incurred in the system after opening the switches on single hour load and twenty-four hour load model. An effort has been made for optimal tie line switching configuration for twenty-four hour load instead of single hour load. In addition, an attempt has been made to maximize the economic benefits in DN with Nr on twenty-four hour load. Switching operation cost is considered to study the effect of frequent Nr on the life span of switches. Second case is used to test the efficacy of the proposed algorithm as compared with other techniques. The performance of AQiEA is tested on two IEEE standard test bus systems. Wilcoxon signed-rank test is also used to demonstrate the effectiveness of AQiEA. [ABSTRACT FROM AUTHOR]

Contingency analysis has been vastly explored within the context of power systems operation and security assessment. However, the impact of power quality indices into the contingency ranking and selection has not been well investigated in the literature. In order to fulfil this gap, a novel approach is proposed in this paper considering the effects of transmission lines outages in the voltage magnitudes and harmonic proliferation in power systems. The compensation theorem is applied to obtain the approximate effect of small changes in the elements of an electric network based on sensitivity analysis with the purpose of determining estimated harmonic voltages and currents in a lower computational time when compared with the traditional application of the iterative Newton–Raphson load flow methodology. Computational simulations are carried out using the IEEE 30 bus test system modified by the inclusion of non linear loads modelled as harmonic current injections. A comparative analysis is also presented considering the contingency selection using the proposed method, load flow algorithms and different ranking factors considering the impact of single contingencies into the power system voltages and total harmonic distortion variations. [ABSTRACT FROM AUTHOR]

This paper presents an improved directional overcurrent protection scheme using a two-stage hybrid GA-IPM algorithm. The developed approach considers the optimal time-current characteristic (TCC) selection and setting calculations of DOCRs simultaneously to protect meshed power networks. The developed formulation considers the optimal choice of the TCC curve and setting calculation simultaneously. Here, the problem is formulated as a mixed-integer nonlinear programming (MINLP) problem where a curve selection setting called curve-setting (CS) is added to the standard time multiplier-setting (TMS) and plug-setting (PS) of each relay in the DOCRs-based protection scheme. In modern relays, the selection of TCC curves is easily made from the available options. In this work, the IEC-standard curves have been considered to obtain the optimum characteristic curve selection and setting calculations. The formulated MINLP problem has been solved using the newly developed two-stage hybrid GA-IPM algorithm. In the first stage, the genetic algorithm (GA) is used to solve the problem formulated as MINLP. The obtained solution is considered the initial solution for the interior-point method (IPM) in the second state. The GA can solve the MINLP problems effectively, and IPM is superior in solving nonlinear programming problems, hence fine-tuning the results obtained by GA. The suitability and effectiveness of the proposed approach have been demonstrated on the IEEE 14 bus test system. Further, the efficacy of the developed method has been validated on an extensive IEEE 118 bus test system, and results are compared with those available in the literature. [ABSTRACT FROM AUTHOR]

The optimal reactive power dispatch (ORPD) problem is a critical factor in maintaining the safe and efficient operation of electric networks. Due to its mixed-variable nonlinear nature, addressing this problem requires an appropriate optimization algorithm. In this study, a novel approach based on the combination of artificial rabbits optimization (ARO) and gradient-based optimization (GBO) algorithms was proposed to solve the ORPD problem in electric networks. The performance of the proposed AROGBO algorithm were verified on 7 numerical optimization test functions. To evaluate the effectiveness of this hybrid AROGBO technique, standard IEEE-30, IEEE-57 bus, and IEEE-118 bus test systems were employed, with two objective functions tested for each system: minimum total power loss and minimum total voltage deviations. The AROGBO, ARO, and GBO algorithms were utilized in each case to determine the optimal values of the generator voltage, transformer tap changer positions, and reactive power compensation values. A comprehensive comparison was made between the results obtained from the hybrid AROGBO algorithm, standard ARO and GBO algorithms, and other metaheuristic optimization techniques. The simulation attainments verify the accuracy and stability of the proposed AROGBO methodology in solving the ORPD problem. [ABSTRACT FROM AUTHOR]

The technology of combining a negative Poisson's ratio (NPR) anchor cable with a double-layer truss support technology (N-DTST) is a new support technology for deeply buried tunnels. To evaluate the stability of the surrounding rock support after the application of this new support technology in the Sichuan–Tibet Railway tunnels, geomechanical model tests were conducted for the first time. A model test loading system with intelligent numerical control and automated analysis was developed to reveal the changing patterns of displacement and stress in the surrounding rock of tunnels. The test results revealed the following: (1) After the burial depth exceeds 800 m, the tunnel undergoes large deformations with displacements greater than 37.5 mm, and the traditional anchor cable support fails; (2) In the burial depth range of 800–2,000 m, the new support technology can control the surrounding rock deformation, and the surrounding rock displacement is less than 10 mm; (3) After the tunnel excavation, the radial stress decreases and the tangential stress concentrates. When the burial depth is greater than 800 m, the radial stress compensation provided by the anchor cable no longer meets the stability of the tunnel surrounding rock, and the new support technology can provide high stress to support the deeply buried tunnel; (4) After the burial depth exceeds 2,000 m, butterfly-shaped damage occurs on the tunnel surface, the truss structure inside the tunnel is damaged, and the support structure fails, so it is recommended to carry out reinforcement support at the arch shoulder. The research results verify the effectiveness of the new support technology and provide an important reference for the support of the surrounding rock in deeply buried tunnels. Practical Applications: Common Poisson's ratio anchors/ropes or shotcrete are widely used in tunnels as the core support structure. They often fail to meet the requirements of fractured rock, expansive rock, and high-ground-stress soft rock tunnels because they cannot adapt to the large deformation characteristics of the catastrophic rock mass. Based on this, this paper proposed a new support technology: an anchor rod/rope with a negative Poisson's ratio material combined with a double-layer three-dimensional truss for joint support of the tunnel. To verify the feasibility of this technology, the research and development team developed a new design for the structure. To verify the feasibility of this technology, a large-scale geomechanical model test system was developed, and a comparative model test was conducted using this test system in combination with the ground stress environment of the Sichuan–Tibet Railway to verify the effectiveness of the new support technology proposed in this paper, which provides a reference for the world's deep buried tunnel support technology. [ABSTRACT FROM AUTHOR]

This paper intends to model an AGC regulator for a restructured environment using Bare Bone Particle Swarm Optimization (BBPSO). The gain-controlled Proportional–Integral (PI) Controller is designed here to enhance the performance of the BBPSO algorithm along with Gaussian distribution. The practical difficulty in handling the area control error to zero is the sudden variations in load. In practice, the tremendous contribution of deregulation in the power sector causes volatility in frequency and tie-line power deviations. To ensure the robustness of the proposed controller, three different cases of power system transactions have been considered. The performance has been validated by comparing it with Real Coded Genetic Algorithm-tuned PI controller (RCGA-PI) and Differential Evolutionary Algorithm-tuned PI controller (DE-PI) for the five area Thermal-Thermal generation test system. Moreover, the dynamic performance of an extensive range of demands and disturbances of all areas like settling time and overshoot against parametric precariousness has been done on the proposed test system. [ABSTRACT FROM AUTHOR]

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This study aimed to evaluate the sulfur hexafluoride (SF6) tracer technique for estimating methane (CH4) emissions in dual-flow continuous culture systems (DFCCS). In experiment 1 (Exp1), fermenters were filled with water, and known CH4 concentrations (0, 1.35, 2.93, or 4.43 g/d) were injected using permeation tubes with SF6 release rates (3.30 or 9.65 mg/d). Headspace gas was collected using canisters, and the SF6 technique estimated CH4 recovery. Experiment 2 (Exp2) involved a DFCCS fermentation trial with ruminal fluid from three Holstein cows, testing diets with soybean meal or its partial replacement (50%) by Chlorella or Spirulina. Headspace gas was collected at intervals post-feeding. Standard curves for SF6 and CH4 quantification were inadequate for DFCCS samples, with the CH4:SF6 ratio differing from standards, indicating the data needs further SF6 release rate evaluation. In Exp1, a high correlation (r = 0.97) was found between infused and calculated CH4, indicating good repeatability. Low and high SF6 rates performed similarly at low CH4 infusion, but high SF6 overestimated CH4 at high infusion. Exp2 showed CH4 emissions irrespective of SF6 rate and indicated reduced CH4 emissions and increased NDF degradation with algae-containing diets. Further evaluation of the SF6 tracer technique is warranted for DFCCS. [ABSTRACT FROM AUTHOR]

Ensuring safety and efficiency in the rapidly advancing autonomous vehicle (AV) industry presents a significant engineering challenge. Comprehensive performance evaluations and critical scenario testing are essential for identifying situations that AVs cannot handle. Thus, generating critical scenarios is a key problem in AV testing system design. This paper proposes a game-theoretic adversarial interaction method to efficiently generate critical scenarios that challenge AV systems. Initial motion prediction for adversarial and surrounding vehicles is based on kinematic models and road constraints, establishing interaction action spaces to determine possible driving domains. A novel evaluation approach combines reachability sets with adversarial intensity to assess collision risks and adversarial strength for any state, used to solve behavior values for each interaction action state. Further, equilibrium action strategies for the vehicles are derived using Stackelberg game theory, yielding optimal actions considering adversarial interactions in the current traffic environment. Simulation results show that the adversarial scenarios generated by this method significantly increase incident rates by 158% to 1313% compared to natural driving scenarios, while ride comfort and driving efficiency decrease, and risk significantly increases. These findings provide critical insights for model improvement and demonstrate the proposed method's suitability for assessing AV performance in dynamic traffic environments. [ABSTRACT FROM AUTHOR]

This study proposes an improved method of the Artificial Bee Colony (ABC) algorithm for the distribution network in scenarios where distributed generation sources and Soft Open Points (SOPs) are connected to optimize power control. Improvement is achieved by integrating the ABC algorithm with the Grenade Explosion Method and Cauchy to accelerate the ABC algorithm's speed. The objective function is considered to reduce power losses over a day. The proposed method was tested on the IEEE-33 bus test system under various scenarios: Case 1 with 3 DGs installed, Case 2 with 3 DGs and 1 SOP simultaneously installed in the distribution network, and Case 3 having the same configuration as Case 2 but operating for 24 hours. In addition to reducing power losses, the voltage at the nodes in the distribution grid was also improved, maintained above 0.95 pu and close to 1 pu. Case 3 showed that integrating a Wind Turbine (WT), two Photovoltaic (PV) generators, and one SOP during operation resulted in the lowest energy losses, smaller than a system with only one WT and two PVs, and significantly lower than the baseline system without any DGs and SOPs. Therefore, employing SOPs in a distribution network with integrated DGs can offer significant benefits in reducing energy losses. [ABSTRACT FROM AUTHOR]

This study employs an innovative dynamic switching test system to investigate the dynamic switching characteristics of three p-GaN HEMT devices. The dynamic switching characteristics are different from the previous research on the dynamic resistance characteristics of GaN devices, and the stability of GaN devices can be analyzed from the perspective of switching characteristics. Based on the theory of dynamic changes in threshold opening voltage and capacitance caused by electrical stress, the mechanism of dynamic switching characteristics of GaN HEMT devices is studied and analyzed in detail. The test results have shown that electrical stress induces trap ionization within the device, resulting in fluctuations in electric potential and ultimately leading to alterations in two critical factors of the dynamic switching characteristics of GaN HEMT devices, the parasitic capacitance and the threshold voltage. The dynamic changes in capacitance before and after electrical stress vary among devices, resulting in different dynamic switching characteristics. The test system is capable of extracting the switching waveform for visual comparison and quantitatively calculating the changes in switching parameters before and after electrical stressing. This test provides a prediction for the drift of switch parameters, offering pre-guidance for the robustness of the optimized application scheme. [ABSTRACT FROM AUTHOR]

(1) Background: There is an ongoing discussion on the elution efficacy of antibiotic-impregnated cements. Our experiments were intended to clarify if there are differences in the antibiotic elution of HPLC compared with inhibition zone testing using eluates or PMMA discs. (2) Materials and Methods: Two cement brands with different concentrations of the active ingredient were tested in antimicrobial Kirby–Bauer (disc diffusion) assays. Cement platelets were directly applied on the agar plates and their zone of inhibition was measured. In parallel, the platelets were incubated in phosphate buffered saline (PBS) and at distinct points of time transferred into new buffer. At these time points, 50 µL of the bone cement eluates was used for zone of inhibition testing. Standard gentamicin sulfate solutions served as a control in the same test setup. To verify the microbiological investigations, the antibiotic content of the eluates was also measured via high-performance liquid chromatography (HPLC). (3) Results: The experiments with cement eluates showed better differentiable results than the direct application of the cement discs. The results were also comparable to investigations with HPLC and gentamicin sulfate standard solutions. (4) Conclusions: The results of elution rates are influenced by the test system and the period of observation chosen. The microbial test systems reflect the results of HPLC to the same degree and give evidence of the efficacy of the antibiotics. The HPLC tests on eluates were more suitable in representing differences in release characteristics. [ABSTRACT FROM AUTHOR]

Although many performance practices have been operated to enhance government department performance, the outcomes of performance practices have caused some challenges. An important concept in performance management is 'overload'; public employees suffer from the high workload in the operation of many performance management systems. This study first identifies the concept of 'evaluation overload' in managing performance evaluation systems and tests how this overload affects organizational performance. The results indicate that a heavy workload in evaluative processes has direct and indirect impacts on the perceived and archival organizational performance of central agencies in South Korea. [ABSTRACT FROM AUTHOR]

(1) Background: Romanian earthquakes caused severe damage over time to a significant number of constructions, and that is why efforts are being made to make structural systems safer. (2) Methods: For structural systems with protection against seismic actions or vibrational actions that have linear viscous dissipation devices, the requirement to assess the equivalent modal damping rate for the entire functional assembly related to the other dynamic parameters arises. (3) Results: This article presents the analytical development of formulas for the compound damping and circular frequency when anti-seismic devices have different dynamic characteristics and their application in order to solve some real engineering cases of bridges and viaducts in Romania with distinct viscoelastic supports. In support of this idea, some experimental tests on a beam system resting on two different anti-seismic elastic supports highlighted the fact that the compound damping of the system can be calculated with the relations established in this paper, provided that the displacements in the horizontal direction of excitation are in the linear domain. Also, we determined the seismic response considering the Vrancea 1977 accelerogram for critical damping ratios of 5% and 18.5%, and then we obtained the variation in the factor of transmissibility depending on the frequency, in order to highlight the optimized value of the equivalent amortization/damping. (4) Conclusions: In the specific context of Romanian seismicity, seismic isolation through the use of isolators with different characteristics represents an optimal technical solution, and it is also optimal from an economic point of view, with an appropriate level of dynamic isolation obtained. [ABSTRACT FROM AUTHOR]

Docker has gained significant popularity in recent years. With the introduction of Docker Desktop for Windows and macOS, there is a need to determine the impact of the operating system on the performance of the Docker platform. This paper aims to investigate the performance of Docker containers based on the operating system. One of the fundamental goals of this study is to conduct a comprehensive analysis of the Docker architecture. This technology utilizes Linux kernel virtualization mechanisms such as namespaces and cgroups. Upon analyzing the distribution of Docker Desktop for Windows and Docker Desktop for macOS, it was discovered that running the Docker environment on these requires a lightweight virtual machine that emulates the Linux system. This information suggests that the additional virtualization layer may hinder the performance of non-Linux operating systems hosting Docker containers. The paper presents a performance test of the Docker runtime on Linux, Microsoft Windows, and macOS. The test evaluated specific aspects of operating system performance on a MacBook computer with an ×86/64 processor architecture. The experiment carried out examined the performance in terms of CPU speed, I/O speed, and network throughput. This test measured the efficiency of software that utilizes various system resources. [ABSTRACT FROM AUTHOR]

Coal seam cavitation is one of the most effective techniques for gas disaster control in low-permeability coal. Due to the difference in cavitation method and process, the damage degree and fracture development range of the coal body around the cavern are greatly different, and the effect of increasing the permeability of the coal body is further changed. In order to further understand the permeability enhancement mechanism of cavitation technology on low-permeability coal and effectively guide engineering applications, this paper conducted experimental research on the unloading damage and permeability evolution characteristics of coal under different cavitation paths using a coal-rock "adsorption-percolation-mechanics" coupling test system. Through the analysis of coal strength and deformation characteristics, coal damage characteristics, and the evolution law of coal permeability combined with the macroscopic damage characteristics of coal, the strength degradation mechanism of unloaded coal and the mechanism of increased permeability and flow were revealed. The results show that unloading can significantly reduce the strength of coal, and the greater the unloading rate, the more obvious the reduction. The essence of this is that unloading reduces the cohesion and internal friction angle of coal—damage and breakage are the most effective ways to improve the permeability of the coal body. Unloading damaged coal bodies not only significantly improves the permeability of the coal body but also improves the diffusion ability of gas, and finally, shows a remarkable strengthening effect of gas extraction. [ABSTRACT FROM AUTHOR]

The development of a piezoelectric linear motor is presented in this paper, based on the principle of alternating motion, to meet the acting stroke and accuracy requirements for the probe station's motion servo system. By partitioning the stator into tangential and normal components, two tangential actuators are affixed to the base, while two normal actuators are fixed on the preloading mechanism, thereby proposing a novel approach for connecting the stator and base. First, the construction and the working principle of the motor were introduced. Subsequently, the motor's major components were designed through finite element simulation, followed by modeling the motor dynamics and deriving its displacement transfer function. Finally, an experimental prototype was fabricated, and a prototype test system was constructed. The driving method can realize a large stroke operation at a low frequency. The minimum operating frequency of the motor is 1 Hz, the minimum step is 12.55 μm, and the stroke is 105 mm. The study results will promote the development of high-performance probe systems. [ABSTRACT FROM AUTHOR]

Brucellosis in animals is an infectious disease caused by bacteria of the genus Brucella. Known methods for diagnosing brucellosis face some challenges, due to the difficulties in isolating and standardizing the natural brucellosis antigen. In this work, we investigated the possibility of using the fluorescence polarization assay (FPA) with synthetic glycoconjugate biosensing tracers to detect antibodies against Brucella as a new methodology for diagnosing brucellosis. Based on the received results, the synthetic fluorescein-labeled trisaccharide tracer is most effective for Brucellosis detection. This tracer is structurally related to the immune determinant fragment of the Brucella LPS buildup of N-formyl-d-perosamine units, connected via α-(1→3)-linkage at the non-reducing end and α-(1→2)-linkage at the reducing end. The sensitivity and specificity in the case of the use of trisaccharide tracer 3b were 71% and 100% (Yuden's method) and 87% and 88% (Euclidean method), respectively, which is comparable with the diagnostic efficiency of traditionally used serological methods, such as the agglutination test (AT), complement fixation test (CFT), and Rose Bengal test (RBT). Given the known advantages of FPA (e.g., speed, compactness of the equipment, and standard reagents) and the increased specificity of the developed test system, it would be appropriate to consider its widespread use for the diagnosis of brucellosis in animals, including rapid testing in the field. [ABSTRACT FROM AUTHOR]

The given research presents assembling and testing optoelectronic system to record and process signals from fiber-optic sensors. The main optoelectronic systems to record and process the signals from fiber-optic sensors are light source controller and optical power detector. There was assembled controller diagram, which apart from light source includes current source for its adequate operation, as well as the systems necessary for stabilizing its working point. The scheme was modelled for specifying nominal and maximum operation criteria. Construction has been designed in the way, that light source controller includes structures of the current regulation and stabilization super luminescent diode (SLED) and temperature stabilization. Apart from that, there was assembled the microsystem of optical power detector additionally to the light detector, which includes the microsystems of intensification and filtration of the signal measured, processing analog data into digital form, microcontroller, used for preliminary data analysis. Data of optoelectronic systems diagram to record and process the signals from fiber-optic sensors has high response speed, low noise level and sufficient progress. [ABSTRACT FROM AUTHOR]

Reconfiguration strategies are used to reduce power losses and increase the reliability of the distribution systems. Since the optimal reconfiguration problem is a multi-objective optimization problem with non-convex functions and constraints, meta-heuristic algorithms are the most suitable choice for the problem-solving approach. One of the new meta-heuristic algorithms that exhibits excellent performance in solving multi-objective problems is the wild mice colony (WMC) algorithm, which is implemented based on aggressive and mating strategies of wild mice. In this paper, the distribution network reconfiguration problem is solved to reduce power losses, improve reliability, and increase the voltage profile of network buses using the WMC algorithm. In addition, the obtained results are compared with conventional multi-objective algorithms. The optimal reconfiguration problem is applied to the IEEE 33-bus and 69-bus test systems. The comparative study confirms the superior performance of the proposed algorithm in terms of convergence speed, execution time, and the final solution. [ABSTRACT FROM AUTHOR]

Metal‐Organic Frameworks (MOFs) represent a highly promising class of materials with diverse applications, particularly as catalytic materials. However, their synthesis typically yields powders available only at laboratory‐scale quantities, usually in the gram range or less. This study addresses the challenge of testing limited amounts of MOF catalysts for demanding applications, such as multiphase gas‐liquid‐solid reactions in flow, utilizing a packed‐bed microreactor. Specifically, we investigate the performance of a nanoparticle (NP) ‐immobilized Pd@UiO‐66 MOF catalyst in the selective semi‐hydrogenation of phenylacetylene to styrene, serving as a model reaction. Maintaining the Taylor flow regime upstream of the catalyst bed was crucial to ensure reproducible and reliable experimental results. We conducted 88 experiments at varying liquid flow rates, temperatures ranging from 15 to 45 °C, and relative pressures spanning 0.28 to 8 bar. Styrene selectivity within the range of 80–92.3 % was achieved at phenylacetylene conversions below 20 %. Notably, the optimal condition for styrene selectivity (70 %) was attained at 98.9 % phenylacetylene conversion under the lowest H2 pressure and highest temperature, demonstrating the significance of low H2 concentration for achieving optimal styrene selectivity. Remarkably, the catalyst exhibited stable activity and selectivity over a 20 h testing period, indicating its robust performance under prolonged reaction conditions. This study demonstrates the potential of the proposed catalyst testing system as a rapid and efficient approach for early‐stage exploration studies, particularly when limited quantities of catalyst, typically in the gram scale or less, are available. [ABSTRACT FROM AUTHOR]

Passive haptics have long been used to enhance the user's experience in virtual reality (VR). However, creating props to be used in a virtual environment can be a complicated and lengthy process. Current research looks to create passive haptic props based on the layout of, or objects in, the user's real environment. However, we identify three key limitations of current research. Firstly, procedural generation introduces many unknown variables into the design process, which complicates applying such techniques to scenarios requiring knowledge of the virtual environment's layout ahead of time. Furthermore, such techniques limit the size and dimensions of the virtual space to that of the real space. Lastly, current research necessitates pre-scanning or real-time scanning of the user's real environment, often requiring specialist equipment and expertise, thus limiting its generalisability. This research proposes PropOrientedWorldRotation, a technique that attempts to answer the aforementioned limitations and simplify the process of adding haptic feedback to VR applications. We implemented this technique in a demonstration game and give an overview of the steps taken to apply the technique in a real context. We analysed the demonstration system's performance and conducted an initial user evaluation in three different physical environments. While our stress test of the system's performance highlights the necessity for certain optimisations in complex environments, our initial user feedback suggests that users experienced a stronger sense of presence and feelings of safety in our passive haptics-enhanced environment. Hence, we conclude that our proposal has the potential to enhance experiences in VR with haptic feedback. [ABSTRACT FROM AUTHOR]

Power system fault diagnosis is crucial for identifying the location and causes of faults and providing decision-making support for power dispatchers. However, most classical methods suffer from significant time-consuming, memory overhead, and computational complexity issues as the scale of the power system concerned increases. With rapid development of quantum computing technology, the combinatorial optimization method based on quantum computing has shown certain advantages in computational time over existing methods. Given this background, this paper proposes a quantum computing based power system fault diagnosis method with the quantum approximate optimization algorithm. The proposed method reformulates the fault diagnosis problem as a Hamiltonian by using Ising model, which completely preserves the coupling relationship between faulty components and various operations of protective relays and circuit breakers. Additionally, to enhance problem-solving efficiency under current equipment limitations, the symmetric equivalent decomposition method of multi-z-rotation gate is utilized. Furthermore, the small probability characteristics of power system events is utilized to reduce the number of qubits. Simulation results based on the test system show that the proposed methods can achieve the same optimal results with a faster speed compared with the classical higher-order solver provided by D-Wave. [ABSTRACT FROM AUTHOR]

Highlights This paper focuses on the mechanical response and viscoelastic properties of double‐blade composite stiffened structure (DCSS) under low‐velocity impact (LVI). Firstly, the impact resistance and viscoelastic behavior of the DCSS are revealed by LVI testing at four different locations using the same initial velocity. Next, the damage morphologies at the impact locations are observed with ultrasonic A‐ and C‐scan equipment and optical microscopy. At last, the DCSS containing impact damage is implemented for axial compression and the strain values of the DCSS surface are obtained using a strain testing system to reveal its residual properties and buckling behavior. The results show that there are significant differences in the impact damage modes at the four different locations. The maximum impact resistance is observed at location D, while location A has the opposite. The DCSS has a certain viscoelastic behavior at LVI and conforms to an exponential decay model. Moreover, position B presents interface debonding damage due to stiffness discontinuities at the flange and skin bonding and severely weakens the load carrying performance of the DCSS. The impact resistance of different positions is analyzed by LVI experimental results. Viscoelastic properties exist at different impact locations and obey the exponential decay model. Impact damage alters the buckling load and residual strength of the DCSS. The damage mechanism of the triangular zone is revealed by damage morphology. [ABSTRACT FROM AUTHOR]

The Sine–Cosine algorithm (SCA) is efficient but faces challenges in exploitative abilities, slow convergence, and exploration–exploitation balance. This study proposes a novel optimization method, the learning-based sine–cosine algorithm (L-SCA), to solve the optimal power flow (OPF) problem. The basic SCA has been modified with a learning phase operator inspired by TLBO. The SCA handles global exploration, while the learner phase of teaching–learning based optimization (TLBO) offers strong local search capabilities, which can be utilized to enhance the solution neighborhood space provided by the SCA technique. The L-SCA and original SCA algorithms address OPF in IEEE 57-bus, Algerian 59-bus, and IEEE 118-bus power systems, considering twelve cases with a focus on cost savings, voltage stability, voltage profile, emissions, and power losses. The comparative study shows that the proposed L-SCA consistently outperforms standard SCA and other reported methods in all cases for varied-scale standard test systems as well as for a practical power system, within reasonable execution times. For instance, L-SCA in the Algerian 59-bus system cut fuel costs by around 13.13% compared to initial case, equating to annual savings of $2.2 million, while in the IEEE-118 bus system, power loss is significantly reduced to 17.881 MW, marking an 86.5% reduction compared to the base case. [ABSTRACT FROM AUTHOR]

The provision of wireless and battery-free power is key to extending the applications of body-worn sensing electronics. This paper investigates the design of an IPT system for a body-worn scenario where the challenges include highly variable coupling, the requirement for the coil/s to be flexible, and close proximity to the body. Variable coupling results in a system that must operate with received powers ranging over orders of magnitude, whilst the use of flexible coils reduces the Q-factor and results in the potential for inductance variation. The human exposure considerations limit both the maximum field strengths that the wearer of a receiver coil might experience and the field strengths that a third party might be exposed to. In this paper, analytical models are used to identify key design variables and to guide the design synthesis of an IPT system for a wrist-worn medical sensor. Practical circuits to drive the transmit coil and to interface the receive coil with the load electronics are described. A prototype system is tested to validate the theoretical analysis, providing power greater than 2 mW to the sensor over a hemispherical region up to 250 mm in radius from the transmit coil. [ABSTRACT FROM AUTHOR]

To accurately detect the early deterioration of electrical insulation in power cables, an energizing system is required for offline partial discharge (PD) measurements. The damped alternating current (DAC) testing system has emerged as an effective tool for inducing PD events. However, the existing systems often suffer from limitations such as signal interference, low sensitivity, and high costs. To address these issues, this study proposes a novel dual‐resonance DAC testing system that is simple in structure and cost‐effective. The prototype was built for testing 10‐kV distribution cables, and its effectiveness was validated through experimental tests on a cable sample. The results show that this approach significantly improves PD detection sensitivity and successfully completes PD localization. This research contributes to the development of more efficient and affordable DAC generation technology for power cable testing applications. [ABSTRACT FROM AUTHOR]

Together with other “bottom‐up” methods, climate stress testing is becoming a prominent approach for climate change impact assessment of water systems. Compared with traditional approaches, stress testing is: (i) more focused on exploring the vulnerabilities of the system at hand; (ii) potentially more inclusive, being amenable to stakeholder involvement and (iii) well suited to identify robust policy options that better account for the deep uncertainty associated with multiple plausible futures. Stress testing is rapidly evolving and giving rise to new techniques and concepts, but few articles provide an accessible overview that can serve as an introduction to the field. Here, we review the underlying principles and concepts of climate stress testing, providing a guide to the main decisions involved in practical application. Topics include selection of stressors, characterizing and exploring the exposure space and data generation including the use of stochastic data. In a complex world where water decisions are made in the context of wider socio‐ecological systems, stress testing and other bottom‐up methods can support decisions that are not only robust to future uncertainty but also regarded as legitimate by affected communities.This article is categorized under: Engineering Water > Sustainable Engineering of Water Science of Water > Water and Environmental Change Water and Life > Stresses and Pressures on Ecosystems [ABSTRACT FROM AUTHOR]

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The performance of critical components in a sensor testing system may be compromised in a thermal vacuum environment as a result of the impact of extreme temperatures. Moreover, the precision of the angle measurement may be influenced by the thermal deformation effect. This paper presents a simulated analysis of the temperature regulation impact of the thermoelectric cooler (TEC) and outlines the design and optimization process of a sensor test chamber that can function within a consistent temperature range. The mathematical model of TEC is utilized to suggest a design choice, taking into account the aforementioned model, in a temperature-controlled environment with thermal vacuum circumstances. Moreover, the orthogonal test method is employed in combination with the FloEFD finite element analysis to validate the effectiveness of temperature control. In addition, the parameters of the radiation radiator are tuned and designed. Therefore, the temperature range difference inside the test system decreased by 20%. The thermoelectric temperature control system's steady-state model is investigated using the PSpice simulation, based on the equivalent circuit theory. The discovered conclusions establish a theoretical foundation for improving the efficiency of temperature regulation. The design concepts presented in this work, particularly the optimization technique for radiation radiators in aerospace test equipment using thermoelectric cooling temperature control research and development, hold promise for practical implementation. [ABSTRACT FROM AUTHOR]

The timely injection of gangue slurry into the mining space formed after coal mining can scale up the disposal of gangue and control surface deformation. However, the waterproof effect of gangue slurry in the mining space remains unclear, necessitating urgent investigation into the permeability characteristics of compacted backfill bodies of gangue slurry under the action of overburden. In this study, a multi-field coupled seepage test system for backfill materials was developed based on Forchheimer's nonlinear seepage law, and a laboratory preparation method for compacted backfill body (CBB) of gangue slurry after grouting and backfilling in mining space under pseudo-triaxial conditions was proposed. Additionally, the pressure bleeding characteristics of gangue slurry under the action of overburden were studied, the variation law of permeability of the CBB with the axial pressure, a particle size range, and cement dosage was revealed, and the determination method for the permeability level of the CBB and its optimization method were put forward. The research results indicate that there are obvious staged characteristics in the pressure bleeding changes in gangue slurry. Axial pressure, particle size range, and cement dosage all have a significant impact on the permeability of the CBB. The permeability level of the CBB of gangue slurry is within the range of poor permeability and extremely poor permeability. After backfilling into the mining space, gangue slurry exhibits a significant water-blocking effect. [ABSTRACT FROM AUTHOR]

Cancer is a collection of illnesses characterized by aberrant cellular proliferation that can infiltrate or metastasize to distant anatomical sites, posing a notable threat to human well‐being due to its substantial morbidity and death rates worldwide. The potential of plant‐derived natural compounds as anticancer medicines has been assessed owing to their favorable attributes of few side effects and significant antitumor activity. Mangrove plants and their derived compounds have been scientifically shown to exhibit many significant beneficial biological activities, such as anti‐inflammatory, immunomodulatory, antioxidant, neuroprotective, cardioprotective, and hepatoprotective properties. This study summarized mangrove plants and their derived compounds as potential anticancer agents, with an emphasis on the underlying molecular mechanisms. To explore this, we gathered data on the preclinical (in vivo and in vitro) anticancer effects of mangrove plants and their derived compounds from reputable literature spanning 2000 to 2023. We conducted thorough searches in various academic databases, including PubMed, ScienceDirect, Wiley Online, SpringerLink, Google Scholar, Scopus, and the Web of Science. The results demonstrated that mangrove plants and their derived compounds have promising anticancer properties in preclinical pharmacological test systems through various molecular mechanisms, including induction of oxidative stress and mitochondrial dysfunction, cytotoxicity, genotoxicity, cell cycle arrest, apoptosis, autophagy, antiproliferative, antimetastatic, and other miscellaneous actions. Upon thorough observation of the pertinent information, it is suggested that mangrove plants and their derived chemicals may serve as a potential lead in the development of novel drugs for cancer therapy. [ABSTRACT FROM AUTHOR]

An auxiliary polarization formulation of the fragment molecular orbital (FMO) method is developed, combining a basis set correction computed for capped isolated fragments with a polarization obtained from uncapped fragments. For a set of organic and inorganic test systems, it is shown that the total energy and atomic charges are accurately reproduced with respect to full unfragmented calculations. It is demonstrated that the method is accurate for computing electronic excited states. The developed approach is applied to rank the isomers of chignolin from experimental NMR data (PDB: 1UAO) according to their relative energy. Contributions of polarization and basis set effects to pair interactions between fragments are elucidated. [ABSTRACT FROM AUTHOR]

In the operation and control of power systems, load frequency control (LFC) plays a critical role in ensuring the stability and reliability of interconnected power systems. Modern power systems with significant penetration of highly variable and intermittent renewable sources present new challenges that make traditional control strategies ineffective. To address these new challenges, this paper proposes a novel LFC strategy that employs a cascaded fractional-order proportional integral-fractional-order proportional integral derivative with a derivative filter (FOPI-FOPIDN) as a controller. The parameters of the FOPI-FOPIDN are optimised using a variant of the particle swarm optimization (PSO) in the literature called ADIWACO. The effectiveness and scalability of the proposed strategy are validated by extensive simulations conducted on two- and three-area test systems and performance comparisons with recent LFC control strategies in the literature. The performance metrics used for the evaluation are ITAE values, deviations in the power flows in the tie-lines, and deviations in the frequencies of the control areas with the power systems subjected to diverse load and RES generation disturbances in several experimental scenarios. Governor dead band, communication time delay, and generation rate constraints are considered in one of the scenarios for more realistic evaluation. Again, the controller's robustness to uncertain model parameters is validated by varying the parameters of the three-area test system by ± 50%. The simulation results obtained confirm the controller's robustness and its superiority over the comparison LFC strategies in terms of the above performance metrics. [ABSTRACT FROM AUTHOR]

This manuscript proposes a hybrid technique for determining the optimal positioning of phasor measurement units (PMUs) in power systems. The PMUs play a crucial role in power system control, wide-area monitoring, and protection. The proposed hybrid method is the joint execution of the Lichtenberg algorithm (LA) and the heap-based optimization (HBO) technique. Hence, it is named the LA-HBO technique. The objective of the proposed method is to place the PMUs in the power system for observability. The goal is to enhance the efficiency and accuracy of PMU placement, ensuring optimal positioning for improved grid monitoring capabilities. The Lichtenberg Algorithm (LA) enhances PMU placement by addressing system observability challenges and ensuring that selected locations provide comprehensive coverage of the power grid. The heap-based approach optimizes PMU placement by efficiently managing the selection process, considering factors like computational efficiency and scalability. The proposed hybrid technique is implemented in IEEE-30 and -14 bus systems. The MATLAB-based simulation results are compared with the various existing methods, such as Sea Lion Optimization (SLO), Particle Swarm Optimization (PSO), and Ant Bee Colony Optimization (ABC). By then, the outcome reveals the efficacy of the proposed method for defining the optimum PMU locations. The proposed method shows a low computational time of 0.02348 sec for the IEEE-14 bus, and 0.03565 sec for the IEEE-30 bus compared with other existing methods. [ABSTRACT FROM AUTHOR]

The main objective of this study was to analyze democracy legitimacy in a non-WEIRD country from a political psychology perspective. More specifically, two dimensions of democracy legitimacy were empirically isolated: diffuse and specific support. We tested a system justification model of democracy legitimacy, while also assessing the role of sociodemographic and context evaluation variables. We applied a questionnaire with closed-ended response choices to a non-probabilistic quota sample of adults from Cordoba, Argentina (n = 450). Besides descriptively analyzing democracy legitimacy, two hierarchical multiple regression analyzes were performed, one for each criterion variable. The results evidenced that diffuse support for democracy remains relatively high, while specific support for Argentine political system is markedly low. Different variables explained each dimension of political legitimacy: those regarding ideological system justification—right-wing authoritarianism, social dominance orientation, and political conservatism—explained an important amount of the variance of diffuse support but had only a marginal role in explaining specific support. The latter was better predicted by context evaluation variables, suggesting that system performance is more relevant than ideology when it comes to specific support. Thus, although democracy legitimacy could be based on a relatively developed civic culture, a poor system performance is not innocuous. The authors discuss how the theoretical explanations developed and framed in Western democracies may be not adequate to comprehend Latin American political culture. [ABSTRACT FROM AUTHOR]

The purpose of the article was to present the results of braking equipment testing and determination of the adequacy of compressed air production of the braking system when the train is loaded. Experimental tests of the braking system of TE33A diesel locomotive in a goods train are performed. According to the initial data the main parameters of the braking system in the empty and loaded train were evaluated. As a result of tests, and according to the calculated data, the dependences of the volume of the main reservoirs, and the dependences of the required compressor capacity, on the number of axles have been obtained. It has been established that the braking system operation in release modes for a 400-axle train corresponds to the operating conditions and the main requirements of the normative documents. [ABSTRACT FROM AUTHOR]

The creep characteristics and potential deformation patterns of gangue backfill material are crucial in backfill mining operations. This study utilizes crushed gangue from the Gangue Yard in Fuxin City as the research material. An in-house designed, large-scale, triaxial gangue compaction test system was used. Triaxial compaction creep tests were conducted on gangue materials with varying particle size distributions. Analysis was performed based on different particle sizes, stresses, and confinement pressures. The study investigates the creep characteristics of the gangue under different conditions and explores the underlying causes. It reveals the relationship between the creep deformation of gangue materials and the passage of time. Mathematical methods are applied to develop a triaxial compaction creep power law model for gangue backfill materials. Finally, the creep results are fitted using an empirical formula approach. [ABSTRACT FROM AUTHOR]

Multi-Dimensional Optimal Power Flow (MDOPF) is a fundamental task in power systems engineering aimed at optimizing the operation of electrical networks while considering various constraints such as power generation, transmission, and distribution. The mathematical model of MDOPF involves formulating it as a non-linear, non-convex optimization problem aimed at minimizing specific objective functions while adhering to equality and inequality constraints. The objective function typically includes terms representing the Fuel Cost (FC), Entire Network Losses (ENL), and Entire Emissions (EE), while the constraints encompass power balance equations, generator operating limits, and network constraints, such as line flow limits and voltage limits. This paper presents an innovative Improved Kepler Optimization Technique (IKOT) for solving MDOPF problems. The IKOT builds upon the traditional KOT and incorporates enhanced local escaping mechanisms to overcome local optima traps and improve convergence speed. The mathematical model of the IKOT algorithm involves defining a population of candidate solutions (individuals) represented as vectors in a high-dimensional search space. Each individual corresponds to a potential solution to the MDOPF problem, and the algorithm iteratively refines these solutions to converge towards the optimal solution. The key innovation of the IKOT lies in its enhanced local escaping mechanisms, which enable it to explore the search space more effectively and avoid premature convergence to suboptimal solutions. Experimental results on standard IEEE test systems demonstrate the effectiveness of the proposed IKOT in solving MDOPF problems. The proposed IKOT obtained the FC, EE, and ENL of USD 41,666.963/h, 1.039 Ton/h, and 9.087 MW, respectively, in comparison with the KOT, which achieved USD 41,677.349/h, 1.048 Ton/h, 11.277 MW, respectively. In comparison to the base scenario, the IKOT achieved a reduction percentage of 18.85%, 58.89%, and 64.13%, respectively, for the three scenarios. The IKOT consistently outperformed the original KOT and other state-of-the-art metaheuristic optimization algorithms in terms of solution quality, convergence speed, and robustness. [ABSTRACT FROM AUTHOR]

Purpose: Accurately measuring sweat sodium concentration ([Na+]) in the field is advantageous for coaches, scientists, and dieticians looking to tailor hydration strategies. The MX3 hydration testing system is a new portable analyser that uses pre-calibrated biosensors to measure sweat [Na+]. This study aimed to assess the validity and reliability of the MX3 hydration testing system. Methods: Thirty-one (11 females) recreationally active participants completed one experimental trial. During this trial, participants exercised at a self-selected pace for 45 min in a warm environment (31.5 ± 0.8 °C, 63.2 ± 1.3% relative humidity). Sweat samples were collected from three measurement sites using absorbent patches. The samples were then analysed for sweat [Na+] using both the MX3 hydration testing system and the Horiba LAQUAtwin-NA-11. The reliability of the MX3 hydration testing system was determined following two measurements of the same sweat sample. Results: The mean difference between measurements was 0.1 mmoL·L−1 (95% limits of agreement (LoA): − 9.2, 9.4). The analyser demonstrated a coefficient of variation (CV) of 5.6% and the standard error of measurement was 3.3 mmoL·L−1. When compared to the Horiba LAQUAtwin-NA-11, there was a mean difference of − 1.7 mmoL·L−1 (95% LoA: − 0.25 X ¯ , 0.25 X ¯ ) and the CV was 9.8%. Conclusion: The MX3 hydration testing system demonstrated very good single-trial reliability, moderate agreement and a very good CV relative to the Horiba LAQUAtwin-Na-11. To further validate its performance, the MX3 hydration testing system should be compared with analytical techniques known for superior reliability and validity. [ABSTRACT FROM AUTHOR]

The pseudo-random number generator (PRNG) based on chaos has been widely used in the fields of digital communication, cryptography and computer simulation. In this paper, we study a new PRNG based on spatial surface chaotic system (SSCS), which is constructed based on coupling mapping lattice (CML) and one-dimensional Logistic chaotic map. To verify the performance of this generator, we study its nonlinear dynamic properties, including the Lyapunov exponent, ergodicity and bifurcation phenomena. Moreover, we analyze the cryptographic properties such as key space, key sensitivity, correlation, histogram and information entropy, while performing NIST SP800-22 test and TestU01 test for the randomness of this system. Theoretical analysis and numerical simulation results show that the PRNG proposed in this paper has good complexity, ergodicity, sensitivity and randomness. Moreover, the key space can increase dynamically with the increase of encrypted data, especially suitable for the protection of big data such as multimedia, which is more advantageous than most existing chaotic mapping. The results of this paper will provide a new idea for the study of chaotic cryptography, and motivate the study of new discrete chaotic models with desirable statistical properties. [ABSTRACT FROM AUTHOR]

To attain high-performance ejector configurations, an ejection characteristic testing system was established initially to validate the reliability of the Realizable k-εturbulent model. Subsequently, optimization investigations were conducted on lobed nozzle ejectors with various structural parameters. The effects of four key structural parameters, including lobed nozzle expansion angle α, lobed nozzle width d, number of lobes in the nozzle n, and height of the square-to-circle section h, were systematically studied. Furthermore, the CRITIC method was employed for multi objective evaluation to identify the optimal design configuration for the casing ejector. The research findings revealed that among the structural parameters, the lobed nozzle expansion angle α exerted the greatest influence on the ejection coefficient and pressure loss coefficient. The weights of the evaluation criteria were determined by the CRITIC method as follows: ejection coefficient (49.38%) < pressure loss coefficient (50.62%). The optimal design configuration determined by the CRITIC method included α = 45°, d = 150 mm, n = 14, and h = 600 mm. The resulting enclosure design ensures smooth airflow within the system, preventing the backflow of high temperature mainstream fluid and heating the enclosure. It also maintains a temperature distribution in the typical cross-section that meets specified requirements. Additionally, it facilitates improved mixing of mainstream and secondary fluid and reduces exhaust gas temperature. [ABSTRACT FROM AUTHOR]

BACKGROUND: Wearing protective helmets is an important prevention strategy to reduce work-related traumatic brain injuries. The existing standardized testing systems are used for quality control and do not provide a quantitative measure of the helmet performance. OBJECTIVE: To analyze the failure characterizations of Type I industrial helmets and develop a generalized approach to quantify the shock absorption performance of Type I industrial helmets based on the existing standardized setups. METHODS: A representative basic Type I construction helmet model was selected for the study. Top impact tests were performed on the helmets at different drop heights using two different impactor masses (3.6 and 5.0 kg). RESULTS: When the helmets were impacted with potential impact energies smaller than the critical potential impact energy values, there was a consistent relationship between the peak impact force and the potential impact energy. When the helmets were impacted under potential impact energies greater than the critical potential impact energy values, the peak impact forces increased steeply with increasing potential impact energy. CONCLUSION: A concept of safety margin for construction helmets based on potential impact energy was introduced to quantify the helmets' shock absorption performance. The proposed method will help helmet manufacturers improve their product quality. [ABSTRACT FROM AUTHOR]

The Transient Stability Constrained Optimal Power Flow (TSCOPF) has become an important tool for power systems today. TSCOPF is a nonlinear optimisation problem, making its solution difficult, especially for small power systems. This paper presents a new optimisation method that incorporates Fitness-Distance Balance (FDB) with the Artificial Ecosystem Optimisation (AEO) algorithm to improve the solution quality in multi-dimensional and nonlinear optimisation problems. The proposed method, named the Fitness-Distance Balance Artificial Ecosystem Optimisation (FDBAEO), also has the capacity to solve the TSCOPF problem efficiently. In order to evaluate the proposed algorithm, it was tested on IEEE CEC benchmarks and on an IEEE 30-bus test system for the TSCOPF problem. Simulation results were compared with the basic AEO algorithm and other current meta-heuristic methods reported in the literature. The results showed that the proposed method was more effective in converging at the global optimum point in solving the TSCOPF problem compared to the other algorithms. This situation indicates that the design changes made in the decomposition phase of the AEO were more suitable for simulating the operation of the algorithm in the real world. The FDBAEO has exhibited a promising performance in solving both single-objective optimisation and constrained real-world engineering design problems. [ABSTRACT FROM AUTHOR]

The specification of requirements and tests are crucial activities in automotive development projects. However, due to the increasing complexity of automotive systems, practitioners fail to specify requirements and tests for distributed and evolving systems with complex interactions when following traditional development processes. To address this research gap, we propose a technique that starts with the early identification of validation concerns from a stakeholder perspective, which we use to systematically design tests that drive a scenario‐based modeling and analysis of system requirements. To ensure complete and consistent requirements and test specifications in a form that is required in automotive development projects, we develop a Model‐Based Systems Engineering (MBSE) methodology. This methodology supports system architects and test designers in the collaborative application of our technique and in maintaining a central system model, in order to automatically derive the required specifications. We evaluate our methodology by applying it at KOSTAL (Tier1 supplier) and within student projects as part of the masters program Embedded Systems Engineering. Our study corroborates that our methodology is applicable and improves existing requirements and test specification processes by supporting the integrated and stakeholder‐focused modeling of product and validation systems, where the early definition of stakeholder and validation concerns fosters a problem‐oriented, iterative and test‐driven requirements modeling. [ABSTRACT FROM AUTHOR]

AbstractCollecting pressure-retaining deep-sea liquid samples is important for the research on in-situ environment and life. A pressure-triggered isobaric sequential liquid sampling system (PTISLSS) was developed for the collection of seawater at target depths. The sampling system comprises six independent seawater collection modules, each containing a titanium sample container and a pre-charged accumulator. A motor-driven sampling mechanism was designed to open and close the fluid channels at depth. Theoretical studies have indicated that the mechanism can generate a contact pressures of up to 160 MPa to ensure the sealing of the samples. The relationship between the pressure of pre-charged gas and the volume of fluid sample has been derived considering the effects of seal friction. The sampling system was built for full-ocean-depth sampling operation and the reliability of the system was tested at a pressure of 120 MPa. The field test was conducted in the West Philippine Basin on a recent scientific research cruise. Pressurized seawater from depths of 2000 to 4500 meters was recovered, and the pressure-retaining rate exceeded 93.5%. The developed sampling system presents satisfactory performance and high operational efficiency, and it will have a wide range of applications in the field of large-scale deep-sea sampling. [ABSTRACT FROM AUTHOR]