Heavy Load Research Articles

Enhanced Transformer Overcurrent Protection via Oil Temperature Acceleration

When a transformer is in a long-term heavy load operation state, the oil temperature reaches the alarm temperature; if a slight fault occurs inside the transformer, traditional inverse time current protection and other protections that react to phase current may not operate due to insufficient sensitivity or they may operate for too long. Based on this, this article proposes a new principle of accelerating inverse time overcurrent protection based on transformer oil temperature. The proposed method uses transformer oil temperature to accelerate the action time of traditional inverse-time overcurrent protection, then introduces the transformer oil temperature factor and acceleration index to optimize the inverse time characteristic curve, and establishes a mathematical model to optimize the adjustment for the complexity of adjustment of the protection action equation and the risk of mismatch of the protection after the acceleration of oil temperature. The existing theoretical analysis and simulation verification results show that the proposed new overcurrent protection scheme based on the transformer oil temperature acceleration inverse time can effectively improve the protection of the rapidity and sensitivity, providing a new research idea for the combination of non-electrical and electrical quantity protection.

Frictional Wear Behavior of Water-Lubrication Resin Matrix Composites under Low Speed and Heavy Load Conditions.

Resin matrix composites are commonly utilized in water-lubricated stern tube bearings for warship propulsion systems. Low-speed and high-load conditions are significant factors influencing the tribological properties of stern tube bearings. The wear characteristics of resin-based laminated composites (RLCs), resin-based winding composites (RWCs), and resin-based homogeneous polymer (RHP) blocks were investigated under simulated environmental conditions using a ring-on-block wear tester. Simulated seawater was prepared by combining sodium chloride with distilled water. The wetting angle, coefficient of friction (COF), and mass loss were measured and compared. Additionally, their surface morphologies were examined. The results indicate a significant increase in the COFs for the three materials with an increased speed or load under dry conditions. The COF of the RLCs is the lowest, indicating that it has superior self-lubricating properties. In wet conditions, the COFs of the three materials decrease with an increasing speed or load, exhibiting a pronounced hydrodynamic effect. The COF and mass loss of RWCs are the highest, while RLCs and RHP exhibit lower COFs and mass loss values. The reticulated texture and flocculent fibers on the surface of RLC enhance the heat diffusion and improve the material wettability and water storage capacity. The surface of RWC is dense, and the friction area under dry conditions is melted and brightened. The surface of RHP is smooth, while the worn material forms an agglomerate and exhibits susceptibility to burning and blackening under dry conditions. The laminated formation method demonstrates superior tribological performance throughout the wear evolution process.

Reliability Enhancement of a Double-Switch Single-Ended Primary Inductance–Buck Regulator in a Wind-Driven Permanent Magnet Synchronous Generator Using a Double-Band Hysteresis Current Controller

The wind power exchange system (WECS) covered in this paper consists of a voltage source inverter (VSI), a DSSB regulator, and an uncontrolled rectifier. An AC grid or a heavy inductive or resistive load (RL) can be supplied by this system. The DSSB is a recently developed DC-DC regulator consisting of an improved single-ended primary inductance regulator (SEPIC) followed by a buck regulator. It has a peak efficiency of 95–98% and a voltage gain of (D (1+D)/(1−D). where D is the regulator transistor’s on-to-off switching ratio. The proposed regulator improves the voltage stability and MPPT strategy (optimal or maximum power-point tracking). The combination of the DSSB and the proposed regulator improves the efficiency of the system and increases the power output of the wind turbine by reducing the harmonics of the system voltages and current. This method also reduces the influence of air density as well as wind speed variations on the MPPT strategy. Classical proportional–integral (PI) controllers are used in conjunction with a vector-controlled voltage source inverter, which adheres to the suggested DSSB regulator, to control the PMSM speed and d-q axis currents and to correct for current error. In addition to the vector-controlled voltage source inverter (which follows the recommended DSSB regulator), classical proportional–integral controllers are used to regulate the PMSM speed and d-q axis currents, and to correct current errors. In addition, a model Predictive Controller (PPC) is used with the pitch angle control (PAC) of WECS. This is done to show how well the proposed WECS (WECS with DSSB regulator) enhances voltage stability. A software-based simulation (MATLAB/Simulink) evaluates the results for ideal and unoptimized parameters of the WT and WECS under a variety of conditions. The results of the simulation show an increase in MPPT precision and output power performance.

Combining Site-Specific Nutrient Allocation Tools Can Decrease Input Demands in No-Till Wheat Farming

ABSTRACT Wheat cultivated under conservation agriculture faces challenges in nutrient management due to altered soil dynamics and heavy residue loads. This often necessitates excessive nutrient applications to address the nutritional demands of the crop. Conducted at the Norman E. Borlaug Crop Research Centre during the winter seasons of 2020–21 and 2021–22, this study explored the effects of different nitrogen (N) application strategies on the ‘HD 2967’ wheat cultivar planted amidst rice residues using a super-seeder. The Nutrient Expert® (NE) combined with LCC-based N top dressing (NE+LCC) demonstrated the most optimal nutrient balance, leading to a 5.9% increase in grain yield and a 42.8% increase in dry matter accumulation compared to traditional methods. The composite SSNM treatments like NE+SPAD and NE+LCC recorded 48.9% and 41.9% higher SPAD values, respectively, as compared to RDF. The NE treatments resulted in significant savings, with a reduction of 60% in phosphorus usage and 5% in potassium. Economically, the NE treatment proved superior, showcasing a 12.7% higher net return compared to the RDF approach. The study concludes that site-specific nutrient management, facilitated by advanced tools like LCC and SPAD, when integrated with software-driven strategies, boosts wheat yield and fosters sustainable farming practices. This approach minimizes environmental impacts by optimizing nutrient applications and aligns with the sustainability development goal of responsible consumption and production.

The influence of Multi-Layer Plastic Packaging (MPP) on the high-temperature performance of asphalt binders and mixtures using wet and dry mixing methods

ABSTRACT High temperatures, combined with heavy traffic loads, increase the risk of permanent deformation and reduce the useful lifespan of pavements, leading to a greater need for maintenance and rehabilitation activities throughout the pavement's service life. This study aims to evaluate the effectiveness of recycled thermoplastic additives, specifically Multi-Layer Plastic Packaging (MPP) materials, in enhancing the high-temperature performance of asphalt mixtures. MPP materials, including types such as Polyester, Polyethylene, Nylon, and Metalized Polyester, were used for binder modification in asphalt mixtures. The modification was conducted using both wet and dry methods. The physical and rheological properties of the modified binders were assessed at high temperatures to determine their impact on stiffness and resistance to permanent deformation. The results indicate that MPP materials significantly improve the high-temperature performance of asphalt mixtures by enhancing binder stiffness and resistance to permanent deformation, with the wet method proving more effective than the dry method. These findings highlight the need for developing practical guidelines for incorporating MPP materials in asphalt production in the future and underscore the importance of comprehensive studies on maintenance, rehabilitation, and overall pavement lifecycle costs.

Numerical and experimental investigation on critical stresses due to rail cant

The track integrity is significantly affected by the internal stress state of the rail. The rail cant influences the flexural stress distribution on the rail foot, thereby shifting the critical stress locations. In this study, full-scale lab testing was done for heavy equivalent wheel loads (16–40 tonne) to measure the rail foot stresses. Further, the mathematical model for track design is modified considering the effect of rail cant on stress distribution and compared with the developed finite element model (FEM) and the experimental study conducted. It was observed that the FEM and modified model calculates the rail stresses with better accuracy of around 5% for heavy wheel loads. The rail cant cause redistribution of stresses, making the gauge corner critical to rail failures. It was observed that stresses at the gauge corner are 20% higher than at the field corner of the rail foot.

Integrated Chassis Control for Multi-Axle Vehicles: A Comprehensive Review

Multi-axle vehicles (MAVs) are used to transport heavy loads, navigate challenging terrain, and perform specific tasks. However, designing vehicle control systems for such vehicles is challenging. MAVs, such as trucks, buses, military vehicles, and multi-purpose vehicles, require sophisticated control techniques to increase the stability and ride comfort of such vehicles. This paper provides a comprehensive review of standalone control systems and integrated control systems (ICSs) for the steering, driving/braking, and suspension systems of MAVs, with a particular focus on the optimal tyre force distribution (TFD) in ICSs for MAVs. It also discusses various objective functions and optimisation methods used for the TFD. The findings indicate that optimising TFD significantly improves the stability of MAVs. As such, future studies may consider examining optimising three-axis TFD for MAVs to further improve vehicle stability.

Super-resolution on unstructured coastal wave computations with graph neural networks and polynomial regressions

Accurate high-resolution wave forecasts are essential for coastal communities, but local and even coastal coverage is often still missing due to the heavy computational load of modern state-of-the-art wave models. This study presents a machine learning super-resolution approach that drastically reduces the computational effort, while keeping errors negligible for the majority of forecasting applications. The method consists of first computing a wave forecast on a coarse mesh which is then converted to a forecast of finer resolution with the help of machine learning. To demonstrate the feasibility and the potential for practical applications of this approach, we present a case study of a 44-year hindcast along the French Basque coast over an unstructured mesh. We introduce two machine learning approaches, a graph neural network and a polynomial ridge regression and compare their performances in different sea states and spatial environments. Both models exhibit very small prediction errors for the significant wave heights, with Root Mean Square Errors (RMSEs) ranging from 0.3cm to 2cm, depending on the study region, while being up to 80 times faster than a direct computation of a numerical wave model at the corresponding spatial resolution. To the best of our knowledge, this is the first time that a super-resolution approach is extended to unstructured meshes in the field of coastal sciences.

Steel Structures in Context of Safety, Resilience & Sustainable Construction: Minimizing Environmental Impacts

The study analyzes a G+4 residential building subjected to seismic loads, comparing vertical base shears, material strengths, and foundation design requirements. The results reveal that RCC structures generate significantly higher vertical base shears due to their heavier loads, necessitating larger foundation areas, especially at critical points, and leading to increased construction costs. In contrast, Steel structures, with lower base shears, require smaller foundation areas, reducing both material use and environmental impact. The findings emphasize that Steel structures offer superior seismic performance, cost efficiency, and sustainability by minimizing foundation requirements and associated environmental burdens. This research highlights the importance of material choice in achieving resilient and sustainable construction, particularly in seismic zones, where Steel structures provide a more efficient and environmentally friendly solution compared to RCC structures.

Exploring the validity of perceived velocity in lower-limb resistance exercises with a cluster-set configuration

This feasibility study aimed to explore the relationship between mean propulsive velocity (MPV) and a scale of perceived velocity (SPV) in back-squat and deadlift exercises performed with heavy loads during a cluster-sets resistance training (CS-RT). Twelve resistance trained males (24.1[2.94] years; 80.7[9.05] kg; 172[4.7] cm; 19.1[6.17] %BF; 4.71[2.72] years of training experience) participated. Participants visited the laboratory three times, spaced 72 to 96 hours. Load-velocity profiles for each exercise were measured in first visit. During the second and third visits, participants engaged in CS-RT sessions with different intra-set rest period (20 vs 40 seconds, randomly), and consisted of three sets of squat and deadlift exercises at 80%1-RM. Each set concluded upon reaching a 10% velocity loss on two occasions. Bayesian Pearson correlation coefficients (r), 95% credible intervals (95%CrI) and Bayes factors (BF10) were computed to assess the relationship between variables. A low positive correlation was observed between MPV and SPV in deadlift (r=0.368, 95%CrI [0.144, 0.544]), with strong evidence supporting the alternative hypothesis (BF10=20.7). Interestingly, moderate correlation values were observed in the 40-second CS-RT configuration (r=0.47, 95%CrI [0.144, 0.544]) and in the first set of the deadlift (r=0.44, 95%CrI [0.118, 0.654]). Conversely, a negligible Bayesian correlation was identified for squat (r=0.101, 95%CrI [-0.132, 0.319]), with substantial evidence favoring the null hypothesis (BF10=0.208). In conclusion, a positive correlation between MPV and SPV in deadlift during a CS-RT configuration, indicating potential utility for perceived velocity. However, velocity feedback prior SPV use and validity for squatting warrants further investigation. Keywords: Strength training, Perception, Powerlifting, Physical performance, Cluster training.

A Mobile based Decision Support System for Postural Evaluation of Agricultural Activities with Rapid Entire Body Assessment (REBA)

Agriculture is an unorganized sector and it is a very high drudgery prone profession due to the absence of awareness and entry of advanced agricultural technologies. Many farming activities and operations are carried out by farm workers in the agriculture sector, where they are subject to very poor working conditions which can lead to physical and mental stress. Workers in agriculture experience musculoskeletal disorders in various body parts throughout various agricultural operations. These problems are caused by heavy work loads, repetitive movements, uncomfortable postures, prolonged periods of time spent in neutral or unsupported positions and the use of conventional equipment and implements that are not ergonomically built. The ergonomic risk factors present in the workplace can be examined using various evaluation instruments to ascertain the workers abilities and drawbacks. The work-related risks are measured using the scientifically validated posture assessment instruments. Rapid entire body assessment (REBA) is a technique that assess a person’s complete body including wrists, fore arms, elbows, shoulders, neck, trunk, back, legs and knees. It uses a systematic process to find the postural musculoskeletal disorders and risks associated with the job tasks. A mobile application is developed to assess the agricultural activities on the basis of physiological analysis and postural analysis using REBA ergonomics technique. The application evaluates the drudgery involved in the agricultural work by using physical assessment followed by postural ergonomics methods and provide recommendation of correct posture to avoid developing musculoskeletal disorders.

Characterisation of the Rigid Body Vibration Spectra of Road Transport Vehicles

ABSTRACTFor decades, numerous attempts at re‐creating realistic (vertical) vibrations that purport to represent typical conditions during road transport have been proposed and published. This has and continues to result in a significant number of target power density spectra (PDS) for use in laboratory simulation of vibrations despite the fact that the underlying parameters that influence the vibrations (road surface unevenness and vehicle dynamics) remain largely unchanged. This paper seeks to address this situation by analysing published and measured PDS (129 in total) from a variety of vehicles and road types with the aim of establishing typical PDS. Through the analysis of the frequency of the first natural mode of these PDS, it was found that there exist five typical response PDS (three for steel leaf suspension and two for air ride suspension) that can be considered as representative vibration response PDS for road transport in general. These representative PDS were matched with a two degree‐of‐freedom quarter‐car model representing the heave response of the rigid body motion of the vehicles. The analysis suggests that the higher frequency content of the measured data is not related to rigid body motion but emanates from drivetrain and, in some cases, structural vibrations. These usually comprise numerous harmonics of fixed and varying frequencies as well as transients. As these vibrations are impossible to classify based on vehicle type, it is recommended that the five quarter‐car representative spectral models proposed in this paper—namely, for steel leaf spring suspended vehicles with heavy, moderate and light loads and air ride type vehicles with heavy and light loads—be used for laboratory simulation for the purpose of evaluating the vibration resistance of products and packaged systems. It is suggested that, for most packaged product, this is sufficient to test their ability to survive road transport vibrations. These will yield more realistic vibrations than those endorsed by standards organisations and should have a positive impact on the optimisation of packaging designs and a corresponding reduction in packaging waste. Finally, the need for further work aimed at developing methods to identify and extract fixed and varying discrete frequency vibration as well as transient vibrations was identified.

Optimization Design of Redundant Parallel Posture Adjustment Mechanism for Solar Wing Docking Based on Response Surface Methodology

The parallel mechanism exhibits high stiffness and excellent dynamic response, making it ideal for high-precision applications. In our early work, a novel 6-DOF redundant parallel posture mechanism with four limbs for solar wing docking has been proposed; each limb consists of three links and four joints. This paper primarily focuses on optimization design of the mechanism. The calculation of workspace volume reveals that factors influencing the range of posture adjustment include dynamic platform parameters, static platform parameters, the drive trajectory of each kinematic pair, and the angles between each kinematic pair. A sensitivity analysis was conducted to examine the impact of each parameter on the range of posture adjustment. To reduce computational complexity and improve analysis efficiency, a combined approach of single-factor analysis and response surface methodology (RSM) is used in the paper. Single-factor analysis is utilized to evaluate the effect of each parameter on the posture adjustment range. Based on these results, RSM is used to establish a regression model for parameters; thereby, the optimal parameter combination for the mechanism is determined. The regression coefficient R2 = 0.9374 attests to the validity of the proposed model. Finally, a comparison of the posture adjustment range before and after optimization is presented, providing a foundation for the practical application of the redundant parallel mechanism. This paper introduces a novel structural design concept aimed at resolving the conflict between heavy loads and compact sizes in redundant parallel mechanisms while providing valuable insights for miniaturized design.

Regulation of crop load and quality in sweet cherry cv. ‘Sweet Heart’ using blossom thinning

ABSTRACT Self-fertile cultivars of sweet cherry (Prunus avium) produce heavy crop load that is often associated with small and poor-quality fruits. Therefore, a crop load-management strategy is required to improve the quality of the fruit. In this study, the effect of blossom thinners on fruit set, yield and quality of the fruits was evaluated. Three types of blossom thinners were used at three different concentrations viz., ammonium thiosulphate (ATS) (1, 1.5 and 2%), naphthaleneacetic acid (NAA) (20, 40 and 60 ppm) and corn oil emulsion (1, 2 and 3%). These were sprayed at 80% of the bloom stage. The vegetative, flowering, fruit set and yield parameters were observed and recorded. Fruit quality was evaluated by measuring the physical and chemical characteristics of the fruits at the harvest stage. Negative correlation was found between fruit set and quality of fruit. The reduction in the crop load was associated with enhanced vegetative growth, including higher leaf:fruit ratio, higher supply and availability of photosynthates to the remaining fruitlets and reduced fruit firmness and titratable acidity. Fruit size, weight, volume, hue value, chroma value, soluble solid content (SSC), total sugars, SSC/acid ratio, anthocyanin and ascorbic acid content were enhanced as a result of thinning. The foliar spray of ATS at 2% and NAA at 60 ppm, at 80% bloom proved to be the most effective in reducing crop load and enhancing the fruit quality.

A wide-output buck DC-DC power management IC

-This article designs and develops a wide-input voltage, high-efficiency, small-size, and peak current-mode control step-down DC-DC converter. The Cadence Spectre simulation tool is used for system simulation to verify the performance of the chip. The overall research content of the article includes the function of the output under heavy load, light load and the stability of the output under transient load changes. The specific content of the research is buck synchronous step-down DC-DC converter chip with pulse modulated. It is provided with an input-voltage range of 6 V–80 V and maximum output-voltage range 72 V. The chip possesses wide operating temperature range of −20 °C to 130 °C. The 92 % high-efficiency can be achieved by using a PWM/PFM hybrid modulation method. When achieving transient load jump, the output voltage change shall not exceed 150 mV. The maximum load current of the chip is 1 A. Furthermore, the chip is packaged and samples can be obtained, and the output light load/heavy load, and other functions are tested through the circuit board. In addition, the chip achieved tape out by using 0.18 μm CMOS process with size of 2027 μm × 2020 μm. The converter features current mode control to simplify external compensation and optimize transient response through a wide range of inductors and output capacitors. It can be adopted user-programmable soft-start time to prevent inrush current during startup. It also includes thermal shutdown protection to provide safe and smooth operation in operating conditions.

‘If You Do Not Write, You Dry Up’: Tensions in Teacher Educator Research and Academic Writing

Teacher educators struggle to balance heavy teaching loads, research, writing, and institutional service. This qualitative study uses institutional ethnography to question how college leadership understand the significance of academic scholarship in the professional lives of college-based teacher educators in Israel. Data from interviews with eight college position holders shed light on the working lives of college-based teacher educators and how they are positioned as researcher-writers in an institution where scholarship expectations are blurry. Findings reveal three themes: the importance of academic activity for institutional prosperity, the difficulties in academic scholarship experienced by teacher educators, and the support the institution provides to encourage and maintain academic activity. The discussion contemplates the tensions between institutional and individual teacher educator advancement. The complexity of the institutional structure deserves attention to achieve institutional aims and attend to individual faculty’s professional needs and desires. The implications of this study are significant for leadership in teacher education and higher education around the world, prompting leaders to rethink ways of supporting faculty involved in research and writing alongside teaching and additional roles. Balancing conflicting roles, providing clear expectations, and maintaining an ongoing dialogue between teacher educators and leadership regarding professional development needs can lead to institutional prosperity alongside individual professional advancement.

Study on instrumental coupler for heavy haul train

As a crucial load-bearing component, coupler’s safety is pivotal for sustainable railway industry development and is extensively scrutinized due to its complex loading environment. However, current research predominantly concentrates on the longitudinal dynamic behavior of couplers, neglecting factors such as nodding and shaking during traversals along curves and ramps. This study proposes an innovative method aimed at identifying multiple loads on couplers, which includes longitudinal tension and compression, lateral shaking, and vertical nodding forces. A theoretical load identification method based on strain sum and difference on coupler shank faces under various loading scenarios is established by finite element analysis. To facilitate accurate measurement, Wheatstone bridges are employed for three-dimensional force measurement, facilitating strain calculation and temperature compensation. The validity of the proposed approach is confirmed through comprehensive validation, encompassing finite element simulation, laboratory experimentation, and vehicle tests. Results demonstrate the robustness of the method, with maximum load deviations of 2.32% longitudinally, 22.52% horizontally, and 19.86% vertically observed during laboratory tests. Results indicate the proposed method’s accuracy and efficiency in heavy haul train coupler load assessment.

Mechanisms Underlying Rail Corrugation on Tracks Equipped with Cologne-Egg Fasteners

Rail corrugation is the most common type of abnormal damage in subway track systems, and there is currently no unified theory that fully explains this specific wear phenomenon. In this research, a coupled rigid–flexible dynamics model and a multi-rigid body dynamics model was established, accounting for the effects of fastener systems, to study severe rail corrugation on tracks equipped with Cologne-egg fastener (CE fastener). The low vertical support stiffness of CE fasteners, combined with heavy train loads, leads to the “soft mud effect.” This effect causes the creep force between the wheel and rail to become saturated more easily, which is the root cause of frequent rail corrugation on both tangent tracks and curved tracks with large radii. Additionally, drawing on the theory of friction-driven self-excitation vibration, a finite element model of a wheelset–rails system with CE fasteners was established to study the unstable vibration caused by wheel–rail sliding. An increased friction coefficient increases the tendency toward unstable vibration in a wheelset–CE fastener–rail system. Three types of composite under-rail vibration absorbers were designed to suppress rail corrugation, with the continuous-type absorber demonstrating the best suppressive effect.

A new multi-DOF envelope forming process for fabricating spiral bevel gears with back taper tooth

Spiral bevel gears are critical transmission components, and are widely used in the aerospace field. This paper proposes a new multi-DOF envelope forming process for fabricating spiral bevel gears. Firstly, the multi-DOF envelope forming principle of spiral bevel gears is proposed. Secondly, the design methods for the envelope tool geometry and movement are proposed based on the envelope geometry and movement relationships. Thirdly, the metal flow and tooth filling laws are revealed through 3D FE simulation of the multi-DOF envelope forming process of a typical spiral bevel gear. Fourthly, a new method for separating the envelope tool and the formed spiral bevel gear with back taper tooth is proposed to avoid their interference. Finally, experiments on multi-DOF envelope forming of this typical spiral bevel gear are conducted using new heavy load multi-DOF envelope forming equipment. The simulation and experimental results show the feasibility of the proposed multi-DOF envelope forming process for fabricating spiral bevel gears with back taper tooth and the corresponding process design methods.

Association of Cartilage, Synovial Fluid and Membrane Pathological Findings in Serbian Mountain Horses Without Signs of Lameness

Abstract Osteoarthritis (OA) in horses often affects the metacarpal/metatarsophalangeal (MCP/MTP) joints and its detection in the early stages is crucial for effective management. I t was hypothesized that the extent of cartilage damage positively correlates with synovial membrane (SM) and synovial fluid (SF) pathological findings in the MCP/MTP joints of Serbian mountain horses that transported heavy loads but did not show signs of lameness. The study was conducted on 32 MCP/MTP joints of eight horses between seven to 12 years of age. Horse limbs were transferred from the abattoir to the necropsy room and SF was sampled. Its appearance, total nucleated cell count (TNCC), mononuclear cell count (MNC), total proteins (TP), and haptoglobin (Hp) were determined. Samples of SM were collected from the dorsal palmar/plantar pouch for histology. A macroscopic examination of gross condylar pathology of the third metacarpal/metatarsal bone was performed with Indian Ink staining. Scoring was done based on Osteoarthritis Research Society International recommendations. SF was clear, pale yellow, and mostly fairly viscous. Half of the samples had TNCC above, and all had TP within the reference range. Hp values were below the reference range and were omitted from further analyses. TNCC correlated with MNC (ρs=0.81, P<0.001), microscopic (ρs=0.62, P=0.003) and macroscopic scores (ρs=0.47, P=0.008). In addition, MNC correlated with macroscopic scores (ρs=0.40, P=0.03). All pathological findings were mild and their correlation indicated that these processes are interrelated and that could be ascribed to early OA.