bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluating the effects of azelaic acid in the metabolism of Arabidopsis thaliana seedlings through untargeted metabolomics and ionomics approaches
Authors: Álvarez‐Rodríguez Sara , Senizza Biancamaria , Araniti Fabrizio , Lucini Luigi , Lucchini Giorgio , Sánchez‐Moreiras Adela M. 
Published: September 2024

AbstractThe present study demonstrates that low concentrations of azelaic acid (AZA) significantly impact the metabolism of Arabidopsis thaliana seedlings, leading to imbalances in numerous minerals and metabolites due to AZA‐induced stress. Untargeted metabolomic analyses were conducted on untreated and AZA‐treated seedlings at two time points: 7 and 14 days after treatment initiation. The results revealed a general accumulation of sugars (e.g., glucose, mannose, xylose), amino acids (e.g., lysine, GABA, threonine, glutamine), and organic acids (e.g., glutaric acid, shikimic acid, succinic acid) in AZA treated‐seedlings, suggesting that AZA triggers stress responses in Arabidopsis. Ionomic analysis revealed that AZA induces phosphorus deficiency, which plants compensate by increasing malate content in the roots. Additionally, AZA treatment induced putrescine accumulation within the root, a metabolic biomarker of potassium deficiency and plant stress. The metabolomic profile showed elevated levels of different specialized metabolites, such as nitrogen‐ and sulphur‐containing compounds, and altered levels of various phytohormones, including jasmonates and brassinosteroids, implicated in plant protection under biotic and/or abiotic stresses. These findings support the hypothesis that AZA's mode of action is associated with an auxin imbalance, suggesting its function as an auxinic herbicide. The observed increases in starch and jasmonates, coupled with the disruptions in potassium homeostasis, are linked to the previously reported alterations in the auxin transport, root architecture and gravitropic root response. Statistical analyses were applied, including Kruskal‐Wallis tests for ionomic data, as well as multifactor analysis, Principal Component Analysis, Orthogonal Partial Least Squares‐Discriminant Analysis, and enrichment pathway analysis for metabolomic data, ensuring the robustness and validity of these findings.
Ultrasonographic Assessment of Testicular Biometry and Arterial Blood Flow in Pre‐ and Postpubertal Miranda Donkeys: Correlations With Semen Quality Parameters
Authors: Martins‐Bessa A. , Quaresma M. , Novoa M. , Bartlewski P. M. , Silva S. 
Published: September 2024

ABSTRACTThe main goals of this study were to document and compare the normal ranges of testicular haemodynamic parameters in pre‐ (aged 8–12 months; n = 4) and postpubertal (aged 24–259 months; n = 16) Miranda donkeys in the breeding season, and to correlate animal biometric data and testicular Doppler indices with basic semen quality parameters of sexually mature jacks. Colour and pulsed‐Doppler ultrasonography were employed to assess blood flow in the left and right distal supratesticular artery (DsTA) and their marginal branches (marginal arteries—MA). Peak systolic velocity (PSV), end diastolic velocity (EDV), pulsatility index (PI) and resistive index (RI) were evaluated in both blood vessels, and TAMV (time‐averaged mean velocity), TABF (total arterial blood flow) and TABF rate (TABF‐R) were calculated for MA. The mean diameter of MA was greater (p < 0.05; 0.24 ± 0.05 vs. 0.19 ± 0.05 cm; mean ± SD) but TABF‐R was less (p < 0.05; 0.004 ± 0.004 vs. 0.02 ± 0.01 mL/s/cm3) in sexually mature donkeys compared with prepubertal animals. Apart from RI values for the right testicle of prepubertal donkeys, PI and RI were consistently greater (p < 0.05) in DsTA compared with MA. Significant correlations were found among select biometric and haemodynamic attributes of the testes (height, width and length, TV, TTV and PSV‐ST) and ejaculate characteristics (volume, sperm defects‐total, head and midpiece) in sexually mature donkeys (n = 8). The present results highlight the importance of scrotal ultrasonography for the reproductive assessment of jacks and provide reference values, based on the available subpopulation of Miranda donkeys that can be used in their clinical and reproductive management and research, or conservation programmes.
An analogue of the Mellin transform for weakly holomorphic cusp forms and a converse theorem
Authors: Imamoḡlu Ö. , Martin Y. , Tóth Á. 
Published: September 2024

AbstractWe define an analogue of the classical Mellin transform for vector‐valued weakly holomorphic cusp forms for and prove a converse theorem for such forms in terms of the new transform. As applications we get converse theorems for scalar valued weakly holomorphic forms for as well as for primes .
Holomorphically conjugate polynomial automorphisms of C2$\mathbb {C}^2$ are polynomially conjugate
Authors: Cantat Serge , Dujardin Romain 
Published: September 2024

AbstractWe confirm a conjecture of Friedland and Milnor: if two polynomial automorphisms and with dynamical degree greater than 1 are conjugate by some holomorphic diffeomorphism , then is a polynomial automorphism; thus, and are conjugate inside . We also discuss a number of variations on this result.
Non-Intrusive Diagnostic Methods for Alternators and Generators Using Electrical Signature Analysis
Authors: Ayers Curtis W. , Haynes Howard D. 
Published: September 2024

Abstract
Electrical Signature Analysis (ESA) was developed originally at Oak Ridge National Laboratory to allow diagnostic related information to be gathered from electric motor driven devices via a remote non-intrusive current measurement on a motor power cable. The resulting signal with appropriate processing is sensitive to mechanical and electrical perturbations occurring in the motor and driven system. This technique has been applied to many different types of AC and DC motors with various driven machines. Recently the ESA technique has been extrapolated to evaluate electro-magnetic devices such as alternators and generators via analysis of their voltage output signals.
The primary goal of this study is to investigate diagnostic methods from established non-intrusive ESA methods and apply them to sound reduction in automobile alternators, diagnostics for rotor and gearbox for helicopter and aircraft generators, and diagnosis of gear problems and electrical winding health for airliner auxiliary power unit generators.
Integrating Vibration, Motor Current, and Wear Particle Analysis With Machine Operating State for On-Line Machinery Prognostics/Diagnostics Systems (MPROS)
Authors: Martin Dana K. , Van Dyke Joe 
Published: September 2024

Abstract
Integration of system process information with expert system vibration analysis to improve the accuracy of rotating machinery fault detection in on-line condition monitoring systems is the main focus of this paper. An overview of the condition based maintenance system MPROS (Machinery Prognostics/Diagnostics System) being developed for the US Navy is presented. Details are provided regarding several currently operating prototype systems installed on both shipboard and land based air conditioning plants. Finally a case study is presented which utilizes data from a prototype system to examine several of the relationships between air conditioning compressor vibration signatures and system process parameters. Understanding and utilizing these relationships will enable accurate diagnostics and provide the in-depth data that is needed to support prognostics.
Neural Adaptive Control of a MIMO Electrohydraulic Servosystem
Authors: Zhang Hao , Ukrainetz Paul , Nikiforuk Peter , Burton Rich 
Published: September 2024

Abstract
Electrohydraulic servomechanisms are well known for their fast dynamic response, high power to inertia ratio, and control accuracy. If the system dynamics can be precisely described and the plant dynamics vary in the vicinity of the designed operation point, a fixed parameter controller may be designed using conventional control theory to acquire the desired output. However, for most industrial systems, it is very difficult to describe the system precisely. In addition, due to disturbances, variations of loads, and changing process dynamics, the system parameters may vary. A neural network approach, using the parallel distributed processing concept with the capability of an ever-improving performance through a dynamic learning process, provides a powerful adaptation ability; its implementation is thus quite feasible for the control of electrohydraulic servosystems.
The objective of this research was to apply the neural network control architecture to a nonlinear multiple input-multiple output (MIMO) electrohydraulic servosystem to improve its position and force output performance. This objective was achieved through the use of a neural adaptive control scheme. A neuro-controller was implemented as a subsystem to control the real-time electrohydraulic system so as to track the desired signals defined by a reference model when subjected to system internal interactions and load variations. Experiments were conducted to illustrate the feasibility and benefits of the neural network approach in comparison with the traditional PID control strategies. The position and force outputs of the plant followed the reference model outputs successfully. The proposed control scheme forced the plant outputs to track those of the reference model simultaneously under changes of the load disturbances.
Identifying a Nonlinear Dynamic System With Partially Recurrent Neural Networks: Feasibility Study and Issues on Error Accumulation Problems
Authors: Ping Xu , Burton Rich , Sargent Colin 
Published: September 2024

Abstract
Conventional methods of modeling transient behavior of an actual system involve developing mathematical equations based on the observed physical relationships among the associated components and engineering practical considerations. In many cases, however, the presence of nonlinearities in actual systems and the difficulties in accurately measuring parameters have restricted the interpretation of the modeling results to specific operating points and or with limited modeling accuracy. An alternate is to establish the mathematical relationships of a system using a system identification approach based on input-output observations. Neural networks show the potential of establishing these mathematical relationships, because of their proven capability of approximating nonlinear functions. This study investigates the use of partially recurrent neural networks to identify transient responses of certain nonlinear systems, and presents the results of a theoretical study which carefully examines the modeling error behavior. The results of this study have established the potential and, indeed limitations to this neural modeling approach. The effect of error accumulation through feedback paths of dynamic models on the modeling accuracy is briefly discussed with an illustrative example.
Robust Performance Control of Electrohydraulic Actuators for Camshaft Machining
Authors: Kim Dean H. , Tsao Tsu-Chin 
Published: September 2024

Abstract
Nonlinear dynamics of the electrohydraulic servoactuator are represented by linear models corresponding to different ranges of motion. Model uncertainty bounds are determined for each amplitude range and the corresponding robust performance controllers are designed. The controllers designed from the larger amplitude models provide robust performance for a wider range of reference signals. The robust performance controllers are implemented with the corresponding repetitive and feedforward controllers for the manufacturing application of camshaft machining. The controllers designed from the larger amplitude models provide better tracking of the larger reference cam trajectories.
The PWM Oil Temperature Control in Hydraulic System Based on MNN Neural Network
Authors: Wei Sun , Hong He , Entao Zhou , Shichang Zhou 
Published: September 2024

Abstract
Based on PWM (Pulse Width Modules) theory, this paper proposes a PWM controlled cooling system by using the on-off water value, the cost of the cooling system is decreased and the reliability is improved. Moreover, this paper proposes a self-learning control algorithm for the control of nonlinear system with large time-delay by taking advantage of MNN (Memmory Neuron Network), it is used in the oil temperature control in hydraulic system, the result is satisfactory, the oil temperature has been controlled within 50±0.5 °C.
Hybrid Analytical/Neural Network Model of Variable Displacement Pump Dynamics
Authors: McNamara John M. , Edge Kevin A. , Vaughan Nick D. 
Published: September 2024

Abstract
The response of a variable displacement pump to a control signal can be an important factor in the overall system response. It is therefore necessary in simulating such systems to have an accurate model of the dynamic behavior of the pump and its interaction with the system. This paper presents a comprehensive model of a typical variable displacement swash-plate piston pump and its servo controller.
Because of the complex and non-linear form of the pumping dynamics previous researchers have used over-simplified models, particularly in respect of swash-plate forces during the pumping cycle. This paper describes a hybrid approach which combines physical models and a neural network to simulate swash-plate dynamics. Training data for the neural network is obtained through a detailed simulation of pumping dynamics. This allows the creation of a black-box model of swash-plate moments as a function of delivery pressure and swash-plate position and velocity.
Training data and the hybrid model of the pump system have been verified experimentally. The final pump system model takes into account the interactions between pump, its controller and the delivery line.
Variable Displacement Gerotor Pump Design
Authors: Tay Yong Fong , Cole Jack H. 
Published: September 2024

Abstract
Attempts to develop variable displacement gear pumps have resulted in designs that are too complex for commercial success. Research at the University of Arkansas has produced an innovative pressure compensated variable displacement gerotor design, described in this paper, that maintains gear pump simplicity. The goal of this continuing research is to develop commercially-viable models of this new concept.
On the Bulk Modulus of Hydraulic Fluids in the Presence of Dissolved Gas
Authors: Stern Hansjoerg 
Published: September 2024

Abstract
This paper documents the initial phase in a program to record and evaluate the effects of air dissolved in hydraulic fluids. Some quantity of dissolved air is a fact of life in most hydraulic systems, yet physical properties of hydraulic fluids are normally reported for the de-aerated or degassed base fluid. While dissolved air effects are generally reported to be “small” or “negligible”, very little quantitative information has been published to document the actual values.
The bulk modulus of fluids is one of the important parameters of all dynamic control systems and plays an important role in the design and life of positive displacement pumps and motors for high pressure service. It was therefore chosen as the initial object of this study and is the basis for the design and construction of the test equipment referred to in this paper.
Initial tests, by no means conclusive, at this stage, seem to verify the assumption of small deviations, but definitely suggest that measurable differences in the trend of bulk modulus with respect to pressure do exist for a aerated SAE10, automatic transmission, and vegetable base hydraulic fluids.
Comparison of Cavitation Erosion Test Results Between Vibratory and Cavitating Jet Methods
Authors: Yamaguchi Atsushi , Kazama Toshiharu , Inoue Kosuke , Onoue Jiro 
Published: September 2024

Abstract
The relationship of the test results between the vibratory and cavitating jet methods was clarified experimentally. Six types of metallic specimens which were made of aluminum alloy, superduralumin, high-strength brass, stainless steel, carbon steel and chrome-molybdenum steel were tested. The ratio of eroded volume by the vibratory to cavitating jet methods became constant as the time proceeded. The eroded volume of aluminum alloy was the largest, and that of superduralumin, that of high-strength brass, that of steel, in order. The order agreed well with both test methods. Striation, plastic deformation and fatigue fracture were observed.
A Dynamic Study of an Air Cylinder for Load Positioning Control
Authors: Fok S. C. , Leow Y. P. 
Published: September 2024

Abstract
This paper analyzes the linearized dynamic characteristics of an air cylinder system for continuous load positioning control. First, the mathematical model of the cylinder system is derived based on a typical electropneumatic valve whose flow characteristics are dependent on both the applied voltage and pressure. Next, the mathematical model associated with a servovalve whose mass flow rate is proportional to the applied voltage is developed. From the mathematical models, the paper discusses the effects of the valves and the load positions on the air cylinder system dynamics. Some simulation and experimental results are given to illustrate the analysis for the control of different start/stop load positioning.
An Integrated Approach to the Design and Maintenance of Pneumatic Power Systems
Authors: Kong K. K. , Chuen C. W. , Leung T. P. , Wong T. T. 
Published: September 2024

Abstract
An integrated knowledge representation for the design, diagnosis and maintenance of physical systems has been developed. This approach can minimize the redundancy of represented knowledge in building expert systems for the design and maintenance of physical systems. In the knowledge of human beings, the design knowledge, diagnosis knowledge and maintenance knowledge of the physical systems are integrated and can be retrieved as required. A thorough analysis on the knowledge of human beings has been carried out in order to determine the critical points which enable the human beings to design, diagnose and maintain physical systems. “Change Theory” is developed to explain the natures of knowledge and the relations among design, diagnosis and maintenance knowledge of physical systems. The natures of knowledge consist of sensation-state-change identification and sensation-state-change initiation. The clustering of the state changes gives rise to different types of knowledge. An integrated knowledge representation for building expert systems is developed with features that keep the redundancy of represented knowledge to a minimum. These features are: i) the knowledge base of the expert system is separated into the knowledge of entities and the knowledge of manipulating the entities; and ii) the inference engine of the expert system is context dependence, which retrieves the corresponding knowledge by checking the preference and non-preference status of the states of the entities. The developed methodology is implemented on an expert system which exhibits design, diagnosis and maintenance of pneumatic power systems.
Nonlinear Optimal Control of a Hydraulically Actuated Positioning System
Authors: McLain Timothy W. , Beard Randal W. 
Published: September 2024

Abstract
In this paper, the nonlinear optimal control problem is formulated for the position control of an electrohydraulic servo system. The optimal control is given by the solution to the Hamilton-Jacobi-Bellman equation, which in this case cannot be solved explicitly. An alternative method, based upon successive Galerkin approximation, is used to obtain an approximate optimal solution. Preliminary simulation results, demonstrating the application of this approach to the position control of a hydraulically actuated device, are presented.
Robust Controller Design for a Variable Displacement Hydraulic Motor
Authors: Plahuta Michael J. , Franchek Matthew A. , Stern Hansjoerg 
Published: September 2024

Abstract
Presented in this paper is the robust control of a variable displacement hydraulic motor (VDHM). A feedback control structure consisting of two nested loops is employed. The inner feedback loop controls the position of the rocker arm which actuates the wobbler plate of the motor. The outer feedback loop regulates the motor shaft velocity such that shaft speed is guaranteed at steady state despite external torque loads. The control loops are closed in succession closing the inner loop first. For each loop design, step response data is collected from a VDHM laboratory test stand to generate analytical systems level models. Based on these models, feedback controllers are designed using classical loop shaping techniques. Feedback control, as opposed to feedforward control, maintains motor shaft velocity under nonpredictive torque loading conditions. In addition, the feedback structure eliminates the need for extensive system calibration when considering system parameter changes that result from component aging.
Nonlinear Adaptive Robust Control of One-DOF Electro-Hydraulic Servo Systems
Authors: Yao Bin , Chiu George T.-C. , Reedy John T. 
Published: September 2024

Abstract
This paper intends to provide a theoretic framework for the high performance robust control of electro-hydraulic servo-systems. This is achieved through applying the recently proposed adaptive robust control (ARC) while taking into account the particular nonlinearities and model uncertainties of the electro-hydraulic servo-systems. In particular, the robust motion control of a typical electro-hydraulic servo-system will be considered. The system consists of an inertia load driven by a double rod cylinder regulated by a two-stage servovalve. The paper will consider the effect of both parametric uncertainties coming from the inertia load and the cylinder and the uncertain nonlinearities such as friction forces. Non-differentiability of the inherent nonlinearities associated with hydraulic dynamics is examined and strategies are provided for handling the non-differentiability of the control term due to the direct change of valve opening when doing backstepping design via ARC Lyapunov function. The resulting controller guarantees a prescribed transient performance and final tracking accuracy in the presence of both parametric uncertainties and uncertain nonlinearities while achieving asymptotic tracking in the presence of parameteric uncertainties.
Osmomechanical Behavior of Plant Cells Across Regions of Elastic and Osmotic Stress
Authors: Walsh John R. , Diller Kenneth R. , Brand Jerry J. 
Published: September 2024

Abstract
Currently, we are developing protocols for cryopreserving select strains of algae from a large culture collection. Protocol design processes for specific organisms involve modeling the coupled osmomechanical behavior of the cells during cryoprotective additive (CPA) exposure. Perfusion cryomicroscopy experiments were conducted to characterize the extent of elastic and osmotic coupling effects upon cell volume changes during exposure of Chlorococcum texanum to step changes in extracellular sucrose concentration. Volume data obtained off-line from video recordings of continuous volumetric changes was combined with inverse solution methods to obtain constitutive property data which includes the cell wall/membrane permeability coefficient for water and the cell wall elastic behavior. Network thermodynamic modeling was employed to simulate the coupling of the elastic and osmotic effects of an algal cell during CPA perfusion. Results from perfusion experiments indicate that a decoupling of elastic and osmotic stresses occurs at the point of incipient plasmolysis. The objective of this study is to construct a robust model of the coupled elastic-osmotic behavior of the algal cells to accurately simulate the volumetric response of algal cells as changes in extracellular solute concentration are encountered during cryopreservation, including severe shrinking and swelling of cells. Volumetric predictions require accurate modeling of the osmomechanical behavior across both elastic and osmotic regimes as well as the transition region of incipient plasmolysis where elastic and osmotic stresses become uncoupled.