Inadequate Load Research Articles

Understanding front-rear track effect of seabed mining vehicle and traction performance optimization

The dual-tracked deep-sea mining vehicles used for sea trials generally cannot meet the demands of large-scale manganese nodules production due to their inadequate load bearing and traction performance. Various seabed mining organizations have gradually started four-tracked mining vehicles as seabed traveling ore collection machines to meet the demand for enhanced tractive performance. A notable challenge encountered is the significant front-rear track effect observed when these vehicles navigate soft-cohesive sediments. Addressing this, our study introduces a novel design concept that involves setting the grouser heights with a deviation between the front and rear tracks, coupled with the development of a traction force-slip rate model inspired by this innovative approach. This model facilitates an in-depth analysis of the front-rear track effect, including phenomena such as deep sinkage and an increase in pitch angle experienced by vehicles on soft-cohesive terrains. It is calculated that the front and rear grouser deviation height of only 2 cm can improve the traction force by 21%. Utilizing the multi-body dynamics (MBD) method, we validated the effectiveness of this grouser height adjustment in mitigating front-rear track effects, demonstrating its potential to reduce sinkage by at least 30 mm and pitch angle by at least 0.3 degrees, thereby guiding the optimization strategy. Finally, through optimization simulation, we present optimized track structural parameter sets suitable for three types of seabed pavement, concluding that for soft silty soil, saturated high cohesive soil, and saturated soft sandy soil, the grouser deviation heights should be approximately 5.3, 4.1, and 2.0 cm, respectively. After applying the optimized track structural parameter sets, traction performance evaluation indexes, such as traction force and the traction force-disturbing area ratio, improved by at least 23.4% and 3.3%, respectively. Meanwhile, static sinkage was reduced by at least 21.4% across the three types of pavements.

Methodology to Investigate Effect of Prosthetic Interface Design on Residual Limb Soft Tissue Deformation.

Residual limb discomfort and injury is a common experience for people living with lower limb amputation. Frequently, inadequate load distribution between the prosthetic device and the residual limb is the root cause of this issue. To advance our understanding of prosthetic interface fit, tools are needed to evaluate the mechanical interaction at the prosthetic interface, allowing interface designs to be evaluated and optimised. Present a methodology report designed to facilitate comprehension of the mechanical interaction between the prosthetic interface and the residual limb. As a pilot study, this methodology is used to compare a hands-on and hands-off interface for a single transtibial prosthesis user using secondary Magnetic Resonance Imaging (MRI) data. MRI data of the residual limb while wearing a prosthetic interface is segmented into a hard tissue and a skin surface model. These models are exported as stereolithography (STL) files. Two methods are used to analyse the interface designs. Firstly, CloudCompare software is used to compute the nearest vertex on the skin surface for every vertex on the compiled internal bony surface for both interface types. Secondly, CloudCompare software is used to compare registered skin surfaces of the residual limb while wearing the hands-on and hands-off interfaces. The maximum and minimum nearest distances between the internal bony surface and skin surface were similar between interface types. However, the distribution of nearest distances was different. When comparing the skin surface while wearing both interfaces, where the fit is more compressive can be visualized. For the dataset used in this study, the classic features of a hands-on Patella Tendon Bearing interface and hands-off pressure cast interface could be identified. The methodology presented in this report may give researchers a further tool to better understand how interface designs affect the soft tissues of the residual limb.

A Study on Behaviour of Clayey and Silty Soils with Granite Dust

A massive amount of granite dust is produced as a byproduct of processing granite rock. Disposing of granite dust is a fatal to human health and is a environmental toxic for land disposal. An attempt was made to use such a material in construction, decrease the disposing problems. Soil, an important material bearing the load of the resisting structure can be available in various layers beneath the earth. Clayey soil and mixture of silt in soil layers exhibits inadequate load bearing ability and shows significant changes in volume with respect to changes in moisture levels. Stabilization of soil is the process that improves the behavior of soil properties. The study investigates the percentage of granite dust that can be a best stabilizer to silty and clayey soil. A series of laboratory tests were conducted to investigate the effects of granite dust. Artificial soil sample were prepared with 0%, 12%, 16%, 20%and 24% with additive as granite dust on silty and clayey soils. Chemical composition of the granite dust was studied for the application of granite dust as a stabilizer. Comprehensive soil tests like liquid limit, plastic limit, Maximum dry density, swell index, shear strength, CBR were performed. A significant decrease was observed in liquid and plastic limit varying with granite dust for both the soils. The dry density increases with an increase in % of granite dust. Swell index shows a decrease rate with increase in granite dust. The shear strength and CBR values gave appropriate increase conclude that granite dust can acts good soil stabilizer for clayey and silty soils.

Design and error compensation of a 3-degrees-of-freedom cable-driven hybrid 3D-printing mechanism

Abstract. In large-scale 3D additive manufacturing (AM), rigid printing mechanisms exhibit high inertia and inadequate load capacity. In this paper, a fully constrained 3-degrees-of-freedom (DOFs) cable-driven hybrid mechanism (CDHR) is developed. A vector analysis method considering error compensation in the pulley system is proposed for analysing the kinematics and dynamics. To address the cable-driven mechanism's strict cable force range requirement, a prescribed-performance controller (PPC) with an adaptive auxiliary system is designed for the nonlinear cable system to enhance the stability and motion accuracy of the end-effector. The stability of the control system is proven using the Lyapunov function. A physical simulation environment using Simscape is developed to verify the vector analysis method and the PPC. Subsequently, an experimental prototype of a 3-DOF CDHR is developed. The results of the error compensation experiment and the prescribed-performance controller experiment demonstrate a 93.321 % reduction in maximum plane error and a 95.376 % reduction in maximum height error for the PPC considering error compensation compared to the non-compensation trajectory. Finally, a double-layer clay-printing experiment is conducted to validate the feasibility of the mechanism.

Investigations of the Bump Foil Bearing With Thick Top Foil Based on Contact Mechanics

AbstractTraditional bump foil bearing, though widely used, is considered to have the problem of inadequate load capacity due to the effect of foil sag between adjacent bumps. In this paper, the thick top foil is applied to cope with the heavy load conditions, which has one order of magnitude larger top foil thickness than traditional top foil. Thick plate and curve shell models are developed to calculate the load-carrying performance of thick top foil bearing based on contact mechanics, and the sag ratio is introduced to describe the degree of foil sag and estimate the bearing load capacity. The impacts of top foil thickness on the stiffness of bearings in different sizes as well as on the adaptability to rotor tilt are discussed. The results indicate that the thick top foil (tt = 2 mm) bearing performs a nearly 100% enhanced load capacity at small gas film thickness whether rotor tilts or not. Thick top foil will increase the bearing stiffness of small size (d = 35 mm) and tends to have little influence on large-size bearing stiffness (d = 70 mm).

Inadequate load output diagnosis of ultra-supercritical thermal power units based on MIWOA multi-label random forest

Aiming at the problem of considerable economic losses caused by the large fluctuation range of response load and Automatic Generation Control (AGC) commanded load of ultra-supercritical thermal power units, an inadequate load output diagnosis model of multi-label random forest with multi-improved whale optimization algorithm (MIWOA-MLRF) is proposed. Thermal power units are a kind of high-dimensional, nonlinear, and complex industrial complex, which brings difficulty for conventional mechanistic models in comprehensively analyzing the inadequate output causes of the units. With the help of extensive data analysis and artificial intelligence algorithms, a multi-label random forest (MLRF) for inadequate output cause analysis is constructed. To improve the accuracy of WOA for MLRF classification, a good point set strategy is used to optimize the initial population distribution of WOA, and an improved convergence factor is used to control the speed of WOA search. Three Gaussian simulation datasets with a different number of features and labels and three sets of thermal power operation data with varying periods are utilized. The test results show that the missing alarm rates (MAR) of MIWOA-MLRF are 0.301, 0.621, and 0.802 under three sets of Gaussian data tests, which are the smallest values among all analytical models. Under three sets of thermal power unit operation data, the average values of MIWOA-MLRF's MAR are 2.2%, 0.2%, and 1.5%, respectively, which have lower missing alarm rates compared with other algorithms. Furthermore, in the false alarm rate (FAR) comparison, the FAR of MIWOA-MLRF decreases significantly compared to MLRF. In the optimization time comparison, the optimization time required for MIWOA-MLRF is about 1000 s, which saves 33% on average compared to the optimization time of other algorithms. The result indicates that MIWOA-MLRF can guarantee the same better real-time performance with reduced FAR and MAR of inadequate output cause classification.

Chaotic slime mould optimization algorithm for optimal load-shedding in distribution system

• Introduces Chaotic Slime Mould Algorithm (CSMA) as an optimal load shedding scheme of islanded DG integrated systems. • A fitness function comprising of maximum amount of remaining load and voltage stability margin (VSM) is adopted. • IEEE 33 bus and IEEE 69 bus distribution systems are used to assess the algorithm’s efficacy. • The proposed CSMA algorithm is compared with Slime mould algorithm (SMA) and Backtrack search algorithm (BSA). In addition, non-parametric statistical analysis have been conducted to adequately compare the algorithms. • In terms of fitness value, time consumption, and convergence characteristics, CSMA outperforms both BSA and SMA. In addition, CSMA ensures a better voltage profile and provides a solution with the least amount of load to be shed. The critical challenge for an efficient islanding operation of a distribution system having Distributed Generation (DG) is preserving the frequency and voltage stability. Contemporary load shedding schemes are inefficient and do not adequately assess the optimum amount of load to shed which results in either excessive or inadequate load shedding. Hence, this paper presents an optimal load shedding technique using Chaotic Slime Mould Algorithm (CSMA) with sinusoidal map in order to achieve greater efficiency. A constrained function with static voltage stability margin (VSM) index and total remaining load after load shedding was applied to accomplish the evaluation. A total of three islanding scenarios of IEEE 33 bus and IEEE 69 bus radial distribution systems were used as test systems to assess the efficacy of the proposed load shedding approach using MATLAB software. To identify performance enhancements, the developed method was compared to Backtrack Search Algorithm (BSA) and the original SMA. According to the results, CSMA outperforms both BSA and SMA in terms of remaining load and voltage stability margin index values in all the test systems.

Comparative analysis of flexural performance of old full-scale hollow slab beams reinforced with fiber composites

To address the problems of inadequate load carrying capacity, deformation and deflection of the main beams of in-service reinforced concrete (RC) bridges, the flexural performance of old full-scale hollow slab beams was investigated based on four-point bending tests in the field, and a qualitative and quantitative comparison was made between innovative solutions (TRC, TRECC) and conventional solutions (prestressed CFRP plates). The results show that the three fibre composite reinforcements increase the load carrying capacity of the hollow slab beams by 9.09% to 21.2% and the stiffiness by 0.4% to 46%, and that the deflection is effectively controlled and limits the development of cracks, while the ductility is reduced. The prestressed CFRP plates are more beneficial in delaying the stiffness degradation under service loads, and the deflection values of their reinforced beams are smaller; while TRECC shows better performance in controlling the crack width. On this basis, the effect of the axial stiffness of the reinforcement on the overall performance and local stress distribution of the beam was evaluated by load calculation and numerical simulations, and showed good agreement between the experimental and theoretical results. The effect of external reinforcement on the beam depends more on the axial stiffness than on the nature of the reinforcement material, and the effect of external reinforcement on the tensile side of the beam is mainly concentrated on the plastic phase.

Use of custom-made acetabular components (CMAC) as part of atwo-stage procedure in patients with severe periacetabular bone loss

Implantation of custom-made acetabular components (CMAC) with load transmission onto the remaining bone stock and reconstruction of the "center of rotation" (COR) in cases of severe periacetabular bone defects. Severe periacetabular bone loss (Paprosky type IIIA/B) with or without pelvic discontinuity after septic or aseptic loosening with inadequate load capacity of the dorsal pillar and/or large supraacetabular defects. Acute or local infections, lack of compliance, taking into account the risks and complications: missing or limited expected postoperative functional gain, multimorbid patients with potential inoperability during the first and/or second intervention. Lateral transgluteal or posterolateral approach while protecting neurovascular and muscular structures. Preparation of the implant site based on preoperative planning with augmentation of bone defects as far as possible. Primarily stable anchoring with 2angle-stable pole screws in the ilium, an optional pole screw in the pubic bone for determination of COR, and stabilization screws in the iliac wing (optionally angle-stable). Use of dual mobility cup according to the soft tissue tension and intraoperative stability. For the first 6weeks postoperative partial weight-bearing (20 kg), followed by agradual increase of the load (10 kg per week). Between 2008 and 2018, 47patients with a Paprosky typeIII defect underwent implantation of amonoflanged CMAC. Main complication was aperiprosthetic joint infection with subsequent need for implant removal in9 of 10cases. Harris Hip Score improved from21.1 to 61.5points. X‑ray imaging displayed an angle of inclination of42.3 ± 5.3°, an anteversion of16.8 ± 6.2°, a∆ H of0.5 ± 0.2 mm and a∆ V of17.7 ± 1.1 mm according to Roessler etal.

Fed‐NILM: A federated learning‐based non‐intrusive load monitoring method for privacy‐protection

Non-intrusive load monitoring (NILM) is essential for understanding consumer power consumption patterns and may have wide applications such as in carbon emission reduction and energy conservation. Determining NILM models requires massive load data containing different types of appliances. However, inadequate load data and the risk of power consumer privacy breaches may be encountered by local data owners when determining the NILM model. To address these problems, a novel NILM method based on federated learning (FL) called Fed-NILM is proposed. In Fed-NILM, instead of local load data, local model parameters are shared among multiple data owners. The global NILM model is obtained by averaging the parameters with the appropriate weights. Experiments based on two measured load datasets are performed to explore the generalization capability of Fed-NILM. In addition, a comparison of Fed-NILM with locally trained NILM models and the centrally trained NILM model is conducted. Experimental results show that the Fed-NILM exhibits superior performance in terms of scalability and convergence. Fed-NILM out performs locally trained NILM models operated by local data owners and approaches the centrally trained NILM model, which is trained on the entire load dataset without privacy protection. The proposed Fed-NILM significantly improves the co-modelling capabilities of local data owners while protecting the privacy of power consumers.

An embedded deep-clustering-based load profiling framework

• A novel load profiling framework using deep clustering to for feature reduction. • Framework eliminates preprocessing in hybrid load profiling algorithms. • Autoencoders capture main non-linear features to separate different load groups. • Improved SI on real-world big data compared to classical clustering techniques. • Framework produces robust load profiles that describe distinct customer groups. Load profiling is an essential step in several smart meter analytics tasks, such as forecasting and planning, that directly impact sustainable energy management. As most real-world smart meter data are unlabeled, the unsupervised learning clustering-driven load profiling approach aims to group related customers based on usage trends. However, due to the curse of dimensionality, conventional clustering algorithms perform poorly and often lead to inadequate load curves. The proposed load profiling framework’s novelty is twofold. First, using an autoencoder the framework represents data as a hierarchy within the layers of the deep network, allowing for dimensionality reduction and highly nonlinear decision separation between clusters at the autoencoder bottleneck level. This is achieved by implementing autoencoder-based clustering that automatically converts smart meter data into more clustering-friendly representations that retain the original data characteristics. Second, the framework integrates dimensionality reduction and clustering into a single end-to-end unsupervised learning framework. The deep clustering framework is then tested on two real-world smart meter datasets, and the experimental results show that the proposed framework produces significantly better load profiles when compared to classical clustering algorithms as well as previous hybrid frameworks proposed in the literature. The paper concludes with a discussion of the results and a set of future directions for improving the load profiling task.

Assessment of Tribological behavior of nickel-nano Si3N4 composite coatings fabricated by pulsed electroplating process

Pure nickel and nano-composite nickel-silicon nitride (Si3N4) coatings were fabricated using pulsed current electrodeposition technique. A control sample for each coating was created and the effect of current density, duty cycle, and pulse frequency on the tribological properties of the electrodeposited coatings was investigated by altering these parameters. X-ray diffraction, scanning electron microscopy and pin-on-disk tests were performed to assess the properties of the fabricated coatings. X-ray diffraction results indicated that both pure and nano-composite coatings possess preferential growth of (111) crystallite planes, which results in the formation of binary symmetrical shaped grains. However, incorporating particles into the coating hindered the growth on other planes, specially (200) growth plane. Incorporation of Si3N4 particles into the coating reduced crystallite size and increased grain refinement; both of which resulted in the increased microhardness of the deposited coatings through dispersion strengthening mechanism. Complementary atomic force microscopy investigations indicated that the roughness of all nano-composite samples was higher than that for the pure nickel coating. After incorporation of Si3N4 particles the wear behavior of all coatings was improved as a result of the improved hardness. Measured wear rates indicate that increasing the current density, during electrodeposition, is the most influencing parameter in reducing the wear coefficient. Furthermore, implementing particles changes the wear mechanism from high plastic deformation, gouging, and delamination to ploughing. Although nano-composite coatings exhibit wider grooves on the surface compared to those on pure nickel coatings, they tend to adhere better to the substrate. The friction coefficient for all nano-composite coatings were marginally higher than that for pure nickel coating, to our understanding, as a result of inadequate load carrying effect of silicon nitride particles.

TL 18086 - Forefoot axial radiographic study for the evaluation of metatarsal head alignment in the coronal plane

Introduction: Many authors consider differences in the relative length of metatarsal bones in the axial plane a cause of inadequate load distribution during gait, leading to metatarsalgia. The goal of surgical treatment is to realign the metatarsal formula. However, many studies have shown a 15% metatarsalgia recurrence rate after reconstructing the advocated metatarsal formula in the axial plane, questioning the importance of the alignment of the metatarsal heads in the coronal plane. Objective: To evaluate the alignment pattern of the metatarsal heads in the coronal plane in individuals with and without metatarsalgia. Methods: This cross-sectional study evaluated individuals aged 30 to 65 years, dividing them into 2 groups, one without foot pain, deformities or callosities and another with metatarsalgia between the 2nd, 3rd and 4th metatarsal bones. The individuals were selected according to inclusion and exclusion criteria and were included in the study after signing an informed consent form. After the selection, the subjects underwent one weight-bearing forefoot axial radiograph evaluating the coronal plane to measure the heights of the metatarsal heads and a weight-bearing anteroposterior foot radiograph to determine the length of each ray. Statistical analysis was performed to compare the measurements of the 2 groups. Results: In total, 106 individuals were divided into 2 groups, each comprising 106 feet, and evaluated. In the group with metatarsalgia, 32% patients were men, the mean age was 49.5 years, and 33 feet had hallux valgus. In the group without metatarsalgia, 51% patients were male, and the mean age was 44.6 years. The measured anthropometric variables did not differ significantly between groups. In both groups, the metatarsal heads were distributed in a curved line in the coronal plane, following the formula M1<M2>M3>M4=M5. The distal support of the 1st ray was in a more plantar position in the group of patients with metatarsalgia (p=0.000). Conclusion: The metatarsal heads of the individuals of both groups were aligned in the coronal plane following the formula M1<M2>M3>M4=M5. However, M1, M4 and M5 were at the same height in the group without metatarsalgia, whereas the M1 weight-bearing point was more plantar in the feet of patients with metatarsalgia.

Some Aspects of the Accommodative Function Condition and Binocular Vision in Adult Patients with Hypermetropia, with Complex Hypermetropic and Mixed Astigmatism

Modern human life conditions are associated with the increase of visual load in the volume and intensity. It determines the social and scientific significance of the study of the visual system functional capabilities with refractive errors. Due to peculiarities such types of ametropia as hypermetropia, hypermetropic and mixed astigmatism are the cause of inadequate load on the visual analyzer. Foreign and Russian scientists mainly pay attention to the study of these functions in childhood, adolescence or presbyopic age. We studied the frequency and degree of binocular and accommodative disorders in adult patients (18–48 years) with hypermetropia, complex hypermetropic and mixed astigmatism. Depending on the type of ametropia, the patients were divided into 2 groups. Group I Hm ast included 58 patients with hypermetropia and complex hypermetropic astigmatism, group II Mixed ast — 60 patients with mixed astigmatism. Patients were divided into two subgroups depending on age: subgroup A included patients aged 18–34 years, subgroup B — patients aged 35–48 years. The control group was 50 persons with emmetropic refraction, which were also divided according to age into two subgroups. In the course of the study, there were noted violations of the accommodative, binocular, oculomotor functions in various combinations of one or several parameters in adult patients with hyperopia, complex hyperopic astigmatism, mixed astigmatism in 10–32 % of cases. A significant percentage of detected latent sensory-motor disorders determines the need for a detailed study of these functions to choose the optimal correction method.

Repair and Reinforcement of Historic Timber Structures with Stainless Steel—A Review

Recent trends in the use of stainless steel profiles for repair and reinforcement of historic timber structures, after degradation due to biotic and non-biotic attacks, are discussed in this paper. These structural challenges can vary from inadequate load carrying capacity to complexities involved with choice of repair materials and techniques. Given the recurring requirements of conservation authorities in terms of reversibility of interventions and compatibility between historic and new materials, an increase in the use of non-invasive reinforcement materials and reversible techniques was observed. Subsequently, engineers and researchers have increasingly employed stainless steel alloys in retrofitting historic timber structures. This paper therefore presents the state of the art in the use of stainless steel profiles in retrofitting timber structural elements within historic structures. It includes a review of the development of the retrofitting methods and existing experimental studies on the mechanical behavior of timber structures reinforced with stainless steel. Finally, it presents a number of case studies and draws conclusions on current trends and practices based on reported studies.

DEGENERATIVE SPINE INJURY ASSOCIATED WITH BACK PAIN: MORPHOGENETIC ASPECTS

Degeneration of the intervertebral disk (IVD) is a pathological process resulting from an interplay between genetic and environmental factors causing structural and functional damage of the IVD and neighboring structures. It is the first stage of degenerative cascade in the vertebral motion segment. Initiation and progression of IVD degenerative processes traditionally involves several factors: inadequate mechanical load, decreased diffusion of nutrients through the arch laminae, and genetic factors playing a significant role in the development of degenerative changes. Three categories of candidate genes whose coding variants are associated with different forms of degenerative changes in the IVD are identified, a conceptual model of genetic interactions in degenerative disease of the disk is developed. The study of the role of structural changes in back pain genesis, evaluation of risk factors allow to optimize the tactics of patient care and find new therapeutic solutions preventing disease progression.

Load management in tendinopathy: Clinical progression for Achilles and patellar tendinopathy

Achilles and patellar tendons are commonly affected by tendinopathy. Injury to these tendons can severely impact upon sports, recreational and everyday activities. Eccentric musculotendinous loading has become the dominant conservative intervention strategy for Achilles and patellar tendinopathy over the last two decades. Eccentric loading involves isolated, slow lengthening muscle contractions. Systematic reviews have evaluated the evidence for eccentric muscle loading in Achilles and patellar tendinopathy, concluding that outcomes are promising but high-quality evidence is lacking. Eccentric loading may not be effective for all patients (athletes and non-athletes) affected by tendinopathy. It is possible that in athletes, eccentric work is an inadequate load on the muscle and tendon. A rehabilitation program aiming to increase tendon load tolerance must obviously include strength exercises, but should also add speed and energy storage and release. The aim of this paper is to document a rehabilitation protocol for Achilles and patellar tendinopathy. It consists of simple and pragmatic exercises designed to incorporate progressive load to the tendon: isometric work, strength, functional strength, speed and jumping exercises to adapt the tendon to the ability to store and release energy. This article would be the first step for an upcoming multicentre randomized controlled trial to investigate its efficacy.

Solar Heating and Cooling in Buildings – How Sustainable?

Conventional heating and cooling systems are responsible for large amounts of carbon dioxide release to the environment, as well as for the use of harmful refrigerants regarding the greenhouse effect and the ozone depletion potential. Solar radiation is a clean form of energy, which is required for almost all natural processes on earth. In South Africa, the majority of produced electricity is generated from fossil fuels and the potential of renewable energy sources is vast, solar radiation in particular is in abundance. The upper limit for Global Horizontal Irradiance (GHI) in South Africa can be as high as 2 300 kWh/m2/a, whereas the Direct Normal Irradiance (DNI) value attains a maximum of 2 900 kWh/m2/a, which is significantly higher than it is in other regions worldwide. The global air conditioning systems market has been estimated to reach 78.8 million units by 2015 due to increasing living standards, comfort expectations and global warming. South Africa is not the best performer regarding renewable energy use among African countries and there is a long way to go to achieve a sustainable environment. This paper seeks to investigate the feasibility and the sustainability of solar driven air conditioning system in South Africa based on meteological weather data. Currently, renewable energy is a topic of interest in South Africa after the 2008 energy emergency when power outages were rolled out due to inadequate maximum load planning. Solar air conditioning technology remains an untapped technology in South Africa.

Athletes' perception of the causes of injury in gymnastics.

Gymnastics requires a high level of flexibility, conditioning and complete body recruitment that is infrequently matched by other sports. Artistic gymnastics has a relatively high incidence of injuries, which are generally of minor or medium severity. With all its complexity, it poses a unique diagnostic and treatment challenge to medical practitioners. The present study examined athletes' perception of the causes of injury and of the possible ways to reduce their incidence. The research involved 63 quality athletes, of whom 20 were in men's artistic gymnastics, 21 in women's artistic gymnastics, and 22 in rhythmic gymnastics. We used the self-assessment method. Factors inducing injury were grouped into three different categories: training, the athlete himself, and the environment. We used the χ2 test to test the association between a risk factor and injuries. The association between injuries and risk factors was also tested using a multivariate logistic regression analysis. Overall, an incidence of 184 injuries was found, of which 67 (36.4%) were acute and 117 (63.5%) were chronic injuries. According to binary logistic regression analyses, psychological factors significantly associated with the prevalence of acute and chronic injury in both sexes for all disciplines were: a poor technique, improper methods of teaching, and an inadequate load. In our study, higher rates of acute and chronic injury were observed among male gymnasts, who reported their occurrence during training by overload, and among female gymnasts, who reported a poor technique, improper methods of teaching, and an inadequate load as main causes of their occurrence. Improving the communication between athletes and coaches, taking the opinion of an athlete into account, and the athlete's active involvement in preparation of the program include the most crucial points for reducing the incidence of injuries.

Optimal Load Shedding Strategy for Selçuk University Power System with Distributed Generation

Traditionally under frequency relays and PLCs (programmable logic controller) are used for load shedding. Recently, these methods have been combined with smart power management systems to shed load automatically. These combined systems are the best methods. However, shedding exact amount of load is almost impossible, because it usually ends up with excessive or inadequate load shedding at feeders where it becomes necessary to sustain system stability. Disconnecting a certain amount of loads at a feeder is defined as load shedding. In case of emergency, faster and optimal load relief can be obtained with an intelligent load shedding system. This paper demonstrates an intelligent load shedding strategy in electrical system of Selçuk University Medical Faculty consisting different type and size of loads and being supplied by a distributed generator. Generators which supply with Selçuk University Medical Faculty can’t meet energy requirement when there is a disturbance in power system. In case of 1 MW Solar power plant to be building at University Campus supply to Medical Faculty, the difference between power generation and demand will decrease. In this case, load shedding becomes necessary to improve reliability of power supply and sustain system stability. Loads are sorted by importance priority and optimal load shedding method is applied. The fuzzy logic is employed for optimal load shedding solution. Strategy is applied on Medical Faculty loads which have different importance level.