Machine Head Research Articles

Artificial Neural Network Model for Predicting Carrot Root Yield Loss in Relation to Mechanical Heading

Modelling and predicting agricultural production processes have high cognitive and practical values. Plant growth, the threat of pathogens and pests, and the structure of agricultural machinery treatments are mostly non-linear, measurable processes that can be described mathematically. In this paper, a multiple regression analysis was carried out in the first step to check the non-linearity of the data and yielded a coefficient of determination of R2 = 0.9741 and the coefficient of determination corrected for degrees of freedom was R2adj = 0.9739. An artificial neural network model, called CH-NET, is then presented to predict the yield loss of carrot roots by leaving root mass in the field during harvest at the mechanical heading stage. The proposed network model has an architecture consisting of an input layer, three hidden layers with 12 neurons each, and an output layer with one neuron. Twelve input criteria were defined for the analysis and testing of the network, eight of which related to carrot root parameters and four to the heading machine. The training, testing, and validation database of the CH-NET network consisted of the results of field trials and tests of the operation of the patented (P.242097) root heading machine. The proposed CH-NET neural network model achieved global error (GE) values of 0.0931 t·ha−1 for predicting carrot root yield losses for all twelve criteria adopted. However, when the number of criteria is reduced to eight, the error increased to 0.0991 t·ha−1. That is, the prediction was realised with an accuracy of 90.69%. The developed CH-NET model allows the prediction of economic losses associated with root mass left in the field or contamination of the raw material with undercut leaves. The simulations carried out showed that minimum root losses (0.263 t·ha−1) occur at an average root head projection height of 38 mm and a heading height of 20 mm from the ridge surface.

Simulation study on the spread characteristics of fires and control measures in high-inclination belt conveyors

Understanding the behavior of high-temperature smoke propagation in roadways during coal mine fires and evaluating control measures are crucial for enhancing safety. This study, based on a significant fire incident at Chongqing Songzao Coal Mine, utilized PyroSim software to model the affected roadway. The laws governing smoke propagation and changes in temperature and CO concentration after fires were simulated and analyzed. Furthermore, the efficacy of combined reverse wind and water spray measures in mitigating the adverse effects of smoke spread was examined. The results indicated that smoke emanated from the fire source and spreads with airflow to the 2# coal bunker of the machine head, bifurcating into left and right paths. Downstream monitoring points exhibited decreasing temperatures with increasing distance from the fire source, while the initial detection time of CO gas increased correspondingly. The combined measures of reverse wind and water spray effectively mitigated smoke reverse spread. Compared to using reverse wind alone, these measures reduced temperatures by 17 °C at the nearest A5 monitoring point to the fire source and reduced CO concentrations by 5200 ppm.

Brain Stroke Detection Using Machine Learning

Abstract: We look at the skills of metamaterials technology to enhance the first-rate of reconstructed photos for the hassle of mind stroke detection. We combine the metamaterial in our headscarf system for mind imaging in CST, and evaluate the reconstructed pix of the pinnacle model this is positioned in the microwave tomographic head machine for the cases with and with out the incorporated metamaterial. For photograph reconstruction we observe the distorted Born iterative technique (DBIM) mixed with two-step iterative shrinkage/thresholding (TwIST) set of rules. Our consequences imply that using our metamaterial can increase the signal distinction due to the presence of a blood goal, which translates into more ac- curate reconstructions of the target.

Mathematical modeling and simulation of generation milling process to manufacture complex face gear surface through multi-axis machine kinematics

Manufacturing of face gear is a complex process, due to its varying geometry, hence the application is not wide as conventional gear geometry. The developments in analytical tools and kinematics of the CNC machine tools motivate researchers to explore the manufacturing process and associated applications. This article presents an efficient method for the generation milling of spur face gear utilizing a nutating head multi-axis CNC machine tool where the tool swings about an arbitrary axis in an inclined plane. The mathematical model of the disk milling cutter and face gear geometry were derived from the shaper geometry by applying the theory of gearing, equation of meshing and coordinate transformation. The cutter location (CL) data was evaluated by aligning the tool orthogonal unit vector and the tooth surface normal vector at the contact point by calculating the appropriate transformation matrices. The evaluation of machine coordinates on a multi-axis CNC milling machine was analyzed with respect to the machine pivot point and the axes movement during generation milling for the face gear drive was studied on the nutating head machine. The NC data is derived from the CL data using the inverse kinematics and the machining simulation was carried out using suitable software. The tooth surface deviation of a maximum of 43.5 μm was observed between the simulated model and the theoretical model, which is well within the requirement of roughing. The generation milling process with the proposed machine configuration is concluded as a profound face gear manufacturing technique.

Role of bone scintigraphy (bone scan) in skeletal osteosarcoma: A retrospective audit and review from tertiary oncology centre

IntroductionBone scan is a investigation which uses radionuclide phosphonate compound for whole skeletal survey. In this current study we have done the analysis of the role of bone scan in skeletal osteosarcoma at tertiary oncology care centre. Material & methodsThis is a retrospective study conducted in a tertiary oncology centre from January 2022 to February 2023. A total of 92 patients with skeletal OGS were included in our study undergone 99 mTCcMDP whole body bone scan. 99 mTc MDP was prepared freshly every morning and dose for each patient were calculated as per EANM guidelines. Images were acquired 2–3 h of post injection. All images were acquired at GE infinia dual head machine with peak setting at 140Kev and LEAP collimator. Suspicious lesions on planer bone scan were correlated with SPECT fused with CT. All the bone scans were reviewed retrospectively by two independent nuclear medicine physicians. ResultsIn this study group, 86 patients with biopsy proven skeletal OGS underwent 99 mTCcMDP bone scan of which 63 were males and 23 were females (2.7:1) with age of study group ranging from 7years to 48years. Patients referred for bone scan were retrospectively categorized in two groups, first group patients (52) were referred for initial staging of disease and second group of patients (34) were referred for follow-up or re-staging of the disease. Total 09 patients showed distant skeletal metastases on bone scan, out of which 05 were in initial staging group and 04 in follow up group. ConclusionOsteosarcoma has propensity to metastasize to many sites in the body however most common site being lung followed by skeletal, nodal and rarely soft tissue metastasis. Bone scan enjoys a optimal sensitivity in case of osteosarcoma to detect skeletal metastasis but have low specificity. However being a cost effective and faster investigation makes it a wise investigation of choice in case of osteosarcoma for skeletal metastasis evaluation.

Brain Stroke Detection Using Machine Learning

Abstract: We look at the skills of metamaterials technology to en- hance the first-rate of reconstructed photos for the hassle of mind stroke detection. We combine the metamaterial in our headscarf system for mind imaging in CST, and evaluate the reconstructed pix of the pinnacle model this is positioned in the microwave to- mographic head machine for the cases with and with out the incorporated metamaterial.

Intraoperative Radiation Therapy

Intraoperative radiation therapy is a developing technology that is being explored at least 60 centers around the world. lt is nota procedure to be undertaken lightly because of high initial startup costs (shielding, modification/adaptation of machine head, operating table modifications, remote monitoring equipment, etc.). It demands dose cooperation between surgeons, physicists, anesthesiologists, radiotherapists, nurses, and other personnel76. IOPT is not without its complications77. Only recently has the ROTG begun to collect data in a prospective fashion forpatients treated with lORT Much investigative work remains to be done, and, at this time, IORT is a modality best suited for facilities that not only have the technological capacity to embark on such a program, but that also can cooperatively collect meaningful data in a prospective fashion and interpret sarne.

Fault diagnosis for rolling bearing of road heading machine via SVDS-ICNN

Fault diagnosis for rolling bearing of road heading machine via SVDS-ICNN

Process Planning with Removal of Melting Penetration and Temper Colors in 5-Axis Hybrid Additive and Subtractive Manufacturing

Hybrid manufacturing (HM), which combines additive manufacturing (AM) and subtractive manufacturing (SM), is effective for the fabrication of thin-walled complex shapes, such as impeller blades. Generally, a process planning for HM is to build a near-net shape through AM and finish its surface through SM. However, in this approach, the cutting tools are limited with long tool lengths and small tool diameters to avoid collisions between the cutting tool and workpiece. In addition, the fabrication shapes are also limited. Therefore, one possible solution is to alternate between AM and SM processes multiple times. In this approach, the workpieces are built gradually as the process progresses. Therefore, the cutting tool can easily avoid collision with the workpiece. However, melting penetration and temper color remain on the finished surfaces using the conventional process planning method with alternate multiple switching. In this process planning, AM and SM processes are alternated. Thus, the finished surfaces are remelted in the subsequent AM process. This heat input causes melting penetration and temper color. These thermal effects must be prevented because these can lead to unfinished part and deterioration of the appearance of the workpieces. Therefore, in this study, a novel process planning method that allows alternate multiple switches without thermal effects is proposed. In addition, a process planning support system that simulates SM process was developed. The SM simulation can detect collision between the cutting tool and workpiece. Using the proposed process planning method, the system plans a process in which thermal effects will not occur. In addition, a case study was conducted using a simulated impeller blade geometry. The results of the case study showed that the developed system could plan by using several cutting tools and parameters of the machining head. The system can estimate the processing time based on the cutting tool path, deposition path, SM process conditions, and AM process conditions. The results validated the developed system and demonstrated its usefulness.

Is There Anybody Out There? Young People from a Bucharest Deprived Neighbourhood in Search of Lost Echo. A photovoice exercise

This article explores in what way and to what extent the life of some teenagers from a disadvantaged urban community is affected by the relationship with formal institutions (school, town hall, police, social assistance, employers / labour market) and relationships with other members of the community (neighbours, friends, acquaintances). The first part of this title obviously refers to the famous song by Pink Floyd “Is there anybody out there?” (The Wall, 1979), but also to the song by Machine Head (2016) “Is Anybody Out There?”, the soloist of the band Rob Flynn saying that “The song is about love, loneliness, racism, and not getting what is going on in the world/America…It’s very much about current events, but applies to a bigger picture.“[1] The second part paraphrases Marcel Proust’s famous novel „In Search of Lost Time”, because the echo of the desires and needs of the young people we are talking about is not found in social policies and everyday realities. The participatory research took place within an illegal camp of recently evicted families, mostly Roma ethnics. Over 100 people (27 families) living in a yard of houses in Bucharest, were evicted on September 2014. The research team designed research using photovoice as a method, involving 10 youngsters from this community, focusing on topics like important things in their life; social relationships – group of friends / family; education; employment – future aspirations, the importance of education in finding a job; involvement / participation in community life. The main conclusion drove toward the fact that for (these) young people, the family is the cornerstone. All their values, dreams, aspirations and needs are gravitating around family and mostly in the absence of almost any effective institutional support. Although at the level of public and political discourse there is a declared interest in improving the situation of adolescents and young people (especially from disadvantaged social segments), included in various strategies, programs and projects and in the speeches of decision-makers and politicians, in reality “real life beats the written strategy”, the discord between the two practically leading to innovative adaptation and survival strategies … but marginal!

Time series clustering-enabled geological condition perception in tunnel boring machine excavation

For automatic geology perception, this paper develops a DTW-Kmedoids-enabled time series clustering framework to gain a clear insight into the geological condition ahead of the tunnel boring machine (TBM) head. The core idea of DTW-Kmedoids is to incorporate dynamic time warping (DTW) as a distance metric into a popular clustering algorithm Kmedoids, aiming to aggregate time series data reflecting similar conditions of surrounding geology into the same cluster. It has been verified in a sequence dataset recording 377 operational rings from a TBM tunneling project in Singapore. Results indicate that the proposed DTW-Kmedoids algorithm outperforms Kmedoids and softDTW-Kmedoids in partitioning the whole dataset into four meaningful clusters on behalf of four geological conditions. Moreover, it shows merits in great robustness to handle varying-length temporal sequences and even fragmentary data instead of the full observations. Furthermore, an online clustering mechanism is well designed to adaptively update the cluster center, which can accomplish the dynamic recognition of the forward geological circumstances ring by ring. In short, the practical value behind the hybrid time series clustering is to automatically and quickly perceive lithology categories along the designed tunnel trail with no requirement of data labeling, possibly allowing for further inference of geological risk and guidance in safe excavation.

Redesain Cold Heading Dies Melalui Pendekatan Metode FMEA dan DFM di PT. ZYX

PT. ZYX is a foreign company automotive component sector for four-wheeled vehicles. In their third year of mass production, the production capacity reached 116 million pcs, resulting in the high cost of Dies purchase for Cold Heading machines. This condition worsened because things such as Dies having a low lifetime and the lead time for Dies purchasement is in the range of 20-40 days or more, which has the potential to cause machine downtime. This study aims to redesign the Dies of Cold Heading machine used today. Completion of the design uses the Pareto diagram analysis, FMEA, and DFM. The analysis result using the FMEA method shows the highest RPN value of 336 with the potential for insert carbide failure that cracks during assembly. The recommended corrective action is to make assembly support components, namely pokayoke parts, and make work instructions for replacing carbide inserts on Dies. The analysis results using the DFM method shows a change in term of cost. The cost for 1 unit of Dies purchasement was initially Rp. 10,247,113.00, but it dwindles to Rp. 4,623,914.23. Using the redesign to make case dies, lock nuts, collets, and stoppers components, resulted in cost efficiency of 54.87%.

Substantiating rational parameters for a stull-timbered device of the selective heading machine

Purpose. To carry out the studies of proposed options for overlapping to support excavation roof and ensure roof maintenance to avoid collapse and protect people and mechanisms. To study a specified goal, an expert assessment of the existing tools to maintain roof rocks in the working area where people and mechanisms are engaged has been carried out. Methodology consists in applying software and computer simulation of interaction processes of mining rocks with arched design options. Findings. A short analysis of the most commonly applied structures to provide temporary fastening of preparatory and permanent mine workings has been carried out. The options for a roof design and the elements for temporary fastening are proposed. The parameters for four sectional overlapping have been substantiated. The loads acting on the roof-supporting structure and the coefficients required to determine the rock loads, the strength of some roof layers and "soil" as well as the forces in the rack hydraulic cylinder have been calculated. Originality. Applying temporary arched fastening in the working area of a tunneling machine promotes reducing a number of technological operations and manual labor employment as well as enhancing maintenance personnel safety. The speed of tunneling works is supposed to increase. Practical value. It is based on the analysis of a selective heading machine performance with an easily collapsed roof, study results to achieve a constructive machine improvement are presented. Its components may vary depending on mining and geological conditions of the work. The obtained parameters are verified by calculations and design solutions. The minimum mass of the fastening that provides both rigidity and strength of the structure is significantly reduced. Obtained results can be applied in underground tunneling and other similar works as well as in constructing roads and railways. The design of the device gives the possibility to adjust the height depending on the mine roof condition.

Clinical LINAC-Based Electron FLASH: Pathway for Practical Translation to Trials of FLASH Radiotherapy

<h3>Purpose/Objective(s)</h3> Studies show ultra-high dose rate (UHDR) radiotherapy (RT), at rates of ≥40 Gy per second, can produce the FLASH effect: reduced toxicity with equal tumor control when compared to conventional RT. Leveraging these benefits for clinical translation can profoundly impact RT. Early clinical trials exhibited safe delivery of UHDR-RT using specialized RT machines. Our prior study showed that a reversible configuration of a standard linear accelerator (LINAC) can be optimized for UHDR output. Here, we explored the components necessary for clinically practical delivery of LINAC-based electron FLASH RT. <h3>Materials/Methods</h3> Using a standard, clinically operational system for image-guided radiation, we configured the program board for a decommissioned electron beam energy for UHDR delivery. No LINAC hardware manipulation or exchange was performed. Key changes included adjustment of the dose per pulse and pulse delivery control using the gating interface. Of note, the scattering foil remained in place within the beam so that field sizes and depth doses could approximate those of standard clinical operations. A commercial electron arc applicator was installed at the face of the gantry using the standard applicator mount to allow for short SSD electron collimation. Copper electron blocks were fabricated with apertures ranging from 3.0 to 20.0 cm. Dose rates were measured at dmax for 100 to 59 cm source-to-surface distances (SSD) (level of machine head) and beam profile measurements were captured at 80 cm SSD using an IC profiler and radiographic film. <h3>Results</h3> UHDR rates ranging from 36.8 to 112.8 Gy/s were measured at 100 to 59 cm SSD, respectively. An 80 cm SSD was selected for treatment arrangement measurements to maintain UHDR and clinical utility, allowing for 13.5 cm of clearance. UHDR ≥60 Gy/s was observed at 80 cm SSD with all field sizes, using a standard, scattered electron beam, with an R80 depth of 6.1 cm, approximating to a 16-18 MeV energy. Average dose per pulse was measured at 0.33 Gy/pulse. Circular block apertures of 3, 10, and 20 cm exhibited beam flatness <5.0 % variability and symmetry of 2.2 to 6.2%. Penumbra width between the 80 and 20% isodose lines (IDL) measured at 0.7, 1.1, and 1.4 cm, respectively. <h3>Conclusion</h3> Optimizing a reversible setup for UHDR irradiation on a standard LINAC, electron delivery at dose rates expected to produce the FLASH effect was achieved. Flat, homogenous field sizes, ranging from 3 to 20 cm of coverage, were obtained at a clinically practical SSD of 80 cm with a treatment depth of 6.1 cm to the 80% IDL. This setup would enable UHDR irradiation at useful depths for a number of different clinical indications, bringing us a step closer to practical UHDR RT using a standard LINAC in future clinical trials.

Chatter Monitoring of Machining Center Using Head Stock Structural Vibration Analyzed with a 1D Convolutional Neural Network.

Real-time chatter detection is crucial for the milling process to maintain the workpiece surface quality and minimize the generation of defective parts. In this study, we propose a new methodology based on the measurement of machine head stock structural vibration. A short-pass lifter was applied to the cepstrum to effectively remove components resulting from spindle rotations and to extract structural vibration modal components of the machine. The vibration modal components include information about the wave propagation from the cutter impact to the head stock. The force excitation from the interactions between the cutter and workpiece induces structural vibrations of the head stock. The vibration magnitude for the rigid body modes was smaller in the chatter state compared to that in the stable state. The opposite variation was observed for the bending modes. The liftered spectrum was used to obtain this dependence of vibration on the cutting states. The one-dimensional convolutional neural network extracted the required features from the liftered spectrum for pattern recognition. The classified features allowed demarcation between the stable and chatter states. The chatter detection efficiency was demonstrated by application to the machining process using different cutting parameters. The classification performance of the proposed method was verified with comparison between different classifiers.

Experimental Investigation of the Tensile Behavior of Selected Tire Cords Using Novel Testing Equipment.

Aramid and polyamide cords are used in a wide range of applications, particularly in the automotive industry (tire reinforcement) and textile industry for military and fireguard purposes. The problem of the reliable experimental study of tensile behavior of synthetic cords is considered in this paper. In the available standards for synthetic cord testing, particularly ASTM D 885-03, the tensile test must result with the cord damage in the middle of gauge length, and the cords should be fixed in the machine clamps. The trial test gave damage near the clamps. We propose a novel testing stage mounted in the testing machine clamps to achieve the uniform tensile stress distribution in the gauge length of the measured cords. The results of the deformations were measured in two ways: using testing machine head displacement and a videoextensometer. Stress curves of four distinguished cords were evaluated and compared. The second method allowed to acquire results differing from the manufacturers’ data from 0.7% to 21.5%, which allowed for the conclusion that the designed test stand allows for obtaining reliable results for stretched cords.

Deformation and Failure Characteristics and Control Technology of Surrounding Rocks in Deep High-Horizontal Stress Rock Roadways in the Wanbei Mining Area

Taking the engineering conditions of the Zhujixi coal mine and Hengyuan coal mine in the Wanbei mining area as the background, based on the investigation of the deformation and failure status of the surrounding rock of the two mines, the deformation and failure characteristics of the surrounding rock of the deep rock roadway in the Wanbei mining area are systematically studied by using the comprehensive research methods of the surrounding rock mechanical parameter test, in situ stress measurements, and numerical simulation. The results show that the measured value of the intermediate principal stress is slightly less than the theoretical value, which is obviously affected by the tectonic stress. The lateral pressure coefficients of the two mines calculated according to the theory are between 1.06 and 1.24 and 1.18 and 1.24, respectively. The simulation shows that when the lateral pressure is higher than 1.5, the arrangement of drilling holes with a depth of 5–10 m and a diameter of 200–300 mm can effectively transfer the stress concentration, proposed using Ф22 L = 2800 mm anchor rods, row spacing 800 × 800 mm, specification Ф 22. For the anchor cable with a length of L = 6,300 mm, the row spacing between anchor cables is 1,600 ± 100 mm, and the coordinated support technology of the reinforcement support and grouting is added. The technology can fully mobilize the deep stable rock stratum when it is applied from the slope change point of 11 coal belt roadways in the east wing of the Zhujixi coal mine to the machine head chamber of 11 coal belt roadways in the west wing, and the field application is good.

Experimental Francis Turbine Cavitation Performances of a Hydro-Energy Plant

An investigation is conducted on the Francis turbine’s cavitation characteristics and its influence on system hydraulic stability using two experimental methods, namely the flow visualization and acoustic emission methods. The investigated turbine is of Francis type with a 15-blade runner and has a specific speed of 202 rpm and a rated head of 30 m. Having tested the machine under a wide range of cavitation conditions, the gap cavitation is the earliest to develop as the cavitation coefficient gradually decreases and has no obvious effect on the machine’s external performance characteristics. The airfoil cavitation follows and causes the increase and decrease in machine flow rate and head, respectively, showing its drag reduction effect, where, at the same time, the pressure pulsation amplitude gets to its peak value. There is also the formation of constant cavitation zones and the involvement of an unsteady surge close to the wall of the draft tube’s cone. Pushing the cavitation coefficient to even lower values, there is the formation of an annular cavitation zone, accompanied by a sharp drop in cone pressure pulsation amplitudes while the former drag reduction effect disappears. The trend of noise is basically the same as that of pressure fluctuation, which confirms its trustworthiness when it comes to cavitation occurrence detection within Francis turbines.

Modelling the Heating Process in the Transient and Steady State of an In Situ Tape-Laying Machine Head

As the use of composite materials increases, the search for suitable automated processes gains relevance for guaranteeing production quality by ensuring the uniformity of the process, minimizing the amount of scrap generated, and reducing the time and energy consumption. Limitations on production by traditional means such as hand lay-up, vacuum bagging, and in-autoclave methods tend not to be as efficient when the size and shape complexity of the part being produced increases, motivating the search for alternative processes such as automated tape laying (ATL). This work aims to describe the process of modelling and simulating a composite ATL with in situ consolidation by characterizing the machine elements and using the finite differences method in conjunction with energy balances in order to create a digital twin of the process for further control design. The modelling approach implemented is able to follow the process dynamics when changes are made to the heating element and to predict the composite material temperature response, making it suitable for use as a digital twin of a production process using an ATL machine.

Target Positioning and Grasping of NAO Robot Based on Monocular Stereo Vision

With the continuous advancement of science and technology and the rapid development of robotics, it has become an inevitable trend for domestic robots to enter thousands of households. In order to solve the inconvenience problem of the elderly and people with special needs, because the elderly and other people in need may need the help of domestic robots due to inconvenient legs and feet, the research of the robot target position based on monocular stereo vision and the understanding of the robot NAO are very important. Research and experiments are carried out on the target recognition and positioning in the process of NAO robot grasping. This paper proposes a recognition algorithm corresponding to quantitative component statistical information. First, extract the area of interest that contains the purpose from the image. After that, to eliminate interference in various fields and achieve target recognition, the robot cameras have almost no common field of view and can only use one camera at the same time. Therefore, this article uses the monocular vision principle to locate the target, and the detection algorithm is based on the structure of the robot head material, establishes the relationship between the height change of the machine head and the tilt angle, and improves the monocular vision NAO robot detection algorithm. According to experiments, the accuracy of the robot at close range can be controlled below 1 cm. This article completes the robot’s grasping and transmission of the target. About 80% of the external information that humans can perceive comes from vision. In addition, there are advantages such as high efficiency and good stability.