Cone Diameter Research Articles

Spray characteristics and combustion mechanism influence on combustion stability of UDMH/NTO pre-combustor under external excitation

To study the combustion stability of liquid rocket engines with hypergolic propellant more comprehensively, external pressure pulse excitation was applied to the UDMH (unsymmetrical dimethylhydrazine)/NTO (methylhydrazine) pre-combustor. The effects of pressure pulse intensity, spray characteristics (droplet diameter and spray cone angle), and combustion mechanism on combustion stability characteristic frequencies and attenuation characteristics after excitation were investigated. The simulation results show that all operation conditions capture the first three longitudinal frequencies of the pre-combustor, and all factors have a greater impact on frequencies with higher orders. Increasing the pulse intensity and reducing the droplet diameter are not conducive to combustion stability. The influence of the spray cone angle on the combustion stability is not monotonous. The pre-combustor has good stability when the spray cone angle is 70°. Different combustion mechanisms have a significant effect on the results before and after pressure pulses, and considering a more complete combustion process may increase the attenuation time in the pre-combustor. The obtained rules can provide a reference for the design and simulation of hypergolic liquid rocket engines, which is beneficial for predicting and evaluating the combustion stability of liquid rocket engines.

Comparative Analysis of Armature Structure on Constant Force Characteristics in Long-Stroke Moving-Iron Proportional Solenoid Actuator

The influence of key design parameters on the constant force characteristics of long-stroke moving-iron proportional solenoid actuators (MPSAs) has been explored by a method combining finite element modelling and correlation analysis. First, the finite element model (FEM) of long-stroke MPSA was developed and validated. Subsequently, the two evaluation indexes, the average-output solenoid force and maximum-output solenoid force variability, were introduced to disclose the influence law of pole shoe parameters on the constant force characteristics of a long-stroke MPSA. After that, correlation analysis was employed to quantify the influence of several parameters and parameter interaction factors on the constant force characteristics. The results indicate a strong contradiction between the average-output solenoid force and maximum-output solenoid force variability; however, increasing the inner diameter of the cone helps enhance the average-output solenoid force without causing maximum-output solenoid force variability to increase. Among all the parameters examined, the cone angle is the most significant parameter affecting the constant force characteristics. Additionally, interactions between the cone angle and the cone length, the cone angle and the inner cone diameter, the cone angle and the outer cone diameter, the cone length and the outer cone diameter, as well as the inner cone diameter and the outer cone diameter also have an important influence on the constant force characteristics. This study deepens our understanding of how the key parameters affect the constant force characteristics and assists designers in optimizing these parameters for developing new structures.

Analysis on the relationship between Schneiderian membrane thickening in the posterior maxillary region and periapical lesions by cone beam computed tomography.

This study aimed to evaluate the thickening of sinus membrane, which is also named Schneiderian membrane (SM), in patients and its relationship with periapical lesions (PAL) in the posterior maxillary region to provide reference for the prevention and treatment of odontogenic maxillary sinusitis. A retrospective analysis was conducted on 554 cone beam computed tomography (CBCT) imaging data of maxillary sinuses from 301 patients who met the inclusion criteria to determine the correlation between PAL and SM thickening in the posterior maxillary region. Cases of pathological SM were recorded and classified on the basis of the degree and type of SM thickening. The correlation between SM thickening and the diameter of PAL, the relationship between the upper edge of PAL and the maxillary sinus floor, and its relationship with whether affected teeth with PAL undergo root canal treatment were evaluated. The detection rate of SM thickening in patients with PAL was significantly higher than in those without PAL, so PAL was correlated with SM thickening. Analysis on the correlation between PAL detection indicators and SM thickening degree showed that SM thickening degree was positively correlated with PAL diameter (cone beam computed tomography-periapical index) and not correlated with the three spread effects between the upper edge of PAL and the maxillary sinus floor, as well as whether the teeth with PAL undergo root canal treatment. The correlation analysis between PAL detection indicators and SM thickening types showed that whether the teeth with PAL undergo root canal treatment was not correlated with SM thickening types, and the diameter of PAL, the three spread effects between the upper edge of PAL, and the maxillary sinus floor were not correlated with SM thickening types. The PAL of posterior maxillary teeth is closely related to SM thickening, and the diameter of PAL is positively correlated with the degree of SM thickening. Patients with PAL who have undergone root canal treatment often exhibit SM polyp thickening. In addition, the relationship between the upper edge of PAL and the maxillary sinus floor does not affect the possibility of SM development.

Standardization of Variable Taper Files and Corresponding Gutta-Percha Cones Amongst Manufacturers

IntroductionCurrently there is no standardization of variable taper endodontic files and corresponding gutta-percha (GP) cones. The aim of this study was to evaluate intramanufacturer and intermanufacturer variability of diameter and taper in the apical third of GP master cones and finishing files from 3 commercially available variable taper endodontic systems. MethodsDiameter measurements were recorded using digital microscopy at 1-mm increments (D1-D4) for F2 files and corresponding GP cones (n = 20 per system) from ProTaper Gold (Dentsply Tulsa Dental Specialties, Johnson City, TN), EdgeTaper Platinum (EdgeEndo, Albuquerque, NM), and ExactTaper H (SS White, Lakewood, NJ). Taper was defined as the rate of change in diameter per 1-mm increment. Mean differences in diameter were assessed using repeated measures of analysis of variance for D1 to D4 and the Wilks test for differences in taper. ResultsIn the apical third, ProTaper and EdgeEndo mean file diameters were significantly smaller than corresponding GP cone diameters (P < .01, P < .01, respectively). Contrastingly, SS White file diameters were significantly larger than their corresponding GP cones (P = .02). Files from all manufacturers had significantly smaller diameters than advertised (nominal) values (P < .01). ProTaper GP cones had similar diameters to nominal values (P = .30), while EdgeEndo and SS White GP cones were significantly smaller (P < .01). Amongst files and corresponding GP cones from all systems, taper was nonstandardized. ConclusionsSize discrepancies between finishing files and corresponding GP cones can be expected amongst variable taper endodontic systems. Therefore, clinicians should be prepared to make intraoperative adjustments when obturating.

Numerical and experimental evaluation of the performance of agravitational vortex turbine rotor

In this study, the evaluation of the rotor performance of agravitational vortex turbine (TVG) for its application indistributed power generation is presented. A numerical analysiswas carried out on a specific configuration of a TVG,characterized by its spiral inlet and conical discharge. Thedimensions of the discharge chamber and the inlet channel, suchas the inlet channel width (w), length (L), and height (h), thedischarge cone height (H) and diameter (d), and the envelopeangle (γ) were determined through previous optimization studiesdocumented in the literature. These dimensions are related to thebasin diameter (D), which was set at 500 mm for this study. Theratios used, such as L/D, h/D, H/D, γ w/D and d/D were 1.518,0.565, 1.572, 92.41°, 0.362, and 0.108, respectively.The rotor has a curvature and a helical pitch angle of 68.8°, has 6blades, a rotor height of 200 mm and the middle section of therotor is 314.4 mm (0.4H) from the top of the discharge cone, withan lower and upper diameter of151.60 mm and 284.44 mm. Usinga three-dimensional computational domain and unsteady flowsimulations, efficiency curves as a function of angular velocitywere obtained. In addition, the TVG was manufactured andexperimental tests were carried out on a laboratory-scale testbench to validate its performance. These tests allowed us tocompare the experimental results (33.84% at 88 RPM) with thenumerical results (32.67% at 106,667 RPM), revealing adifference of 3.37% between the maximum efficiency values. Itis essential to continue the turbine optimization process to ensurethat the designed TVG plays a role in fostering sustainability andfacilitating the shift towards cleaner and sustainable energyalternatives.

Comparative analysis and enhancement of conical component calculation under internal pressure in European pressure vessel Standards

This paper presents a comprehensive analysis of conical components in pressure vessels emphasizing their significance when utilized to transition between different diameters or slopes. A thorough design and analysis are underscored as essential for ensuring the safety and reliability of these components under diverse loading circumstances. The paper aims to propose enhancements to the European Pressure Vessel Standards concerning conical components under internal pressure, with a focus on improving safety, reliability, and compliance with industry standards. Existing European standards are reviewed, identifying potential gaps and proposing practical solutions. The paper also presents research findings on the influence of cone apex angles, shell geometries and design pressure on cone plate thickness calculations. A new methodology for the design and analysis of conical components in pressure vessels is proposed, offering a potential pathway to safer and more efficient pressure vessels. A range of cylinder diameter between 1000 and 2500 mm and cone angles between 30° and 60° are used as input to quantify the difference in cone thickness for a design pressure ranging between 10 and 200 barg. The proposed method yields results much closer to AD2000 compared to EN13445, leading to slightly thicker cones (up to 2.2 mm for the selected range of cone diameters and angles) compared to the former, resulting in safer pressure vessel design, and thinner cones (up to 22 mm) compared to the latter resulting in significant material savings. A comparative analysis was performed through Finite Element Analysis validating the EN13445 unsuitability for cone thickness calculations. A modification is proposed for equation (7.6)-(8) in EN13445 resulting in thinner plates reducing the cone plate thickness difference to 0.9 % on average compared to the current deviation of -9.6 % on average for the selected range of cylinder diameters and cone angles.

Minibeam Radiation Therapy Treatment (MBRT): Commissioning and First Clinical Implementation

Minibeam radiation therapy (MBRT) is characterized by the delivery of submillimeter wide regions of high "peak" and low "valley" doses throughout a tumor. Preclinical studies have long shown the promise of this technique, and we report here the first clinical implementation of MBRT. A clinical orthovoltage unit was commissioned for MBRT patient treatments using 3, 4, 5, 8, and 10 cm diameter cones. The 180 kVp output was spatially separated into minibeams using a tungsten collimator with 0.5 mm wide slits spaced 1.1 mm on center. Percentage depth dose (PDD) measurements were obtained using film dosimetry and plastic water for both peak and valley doses. PDDs were measured on central axis for offsets of 0, 0.5, and 1 cm. The peak-to-valley ratio (PVR) was calculated at each depth for all cones and offsets. To mitigate the effects of patient motion on delivered dose, patient-specific 3D printed collimator holders were created. These conformed to the unique anatomy of each patient and affixed the tungsten collimator directly to the body. Two patients were treated with MBRT, both received 2 fractions. Peak PDDs decreased gradually with depth. Valley PDDs initially increased slightly with depth, then decreased gradually beyond 2 cm. PVRs were highest at the surface for smaller cone sizes and offsets. In vivo film dosimetry confirmed a distinct delineation of peak and valley doses on both patients treated with MBRT with no dose blurring. Both patients experienced prompt improvement in symptoms and tumor response. We report commissioning results, treatment processes, and the first two patients treated with MBRT using a clinical orthovoltage unit. While demonstrating feasibility of this approach is a crucial first step toward wider translation, clinical trials are needed to further establish safety and efficacy.

Thermohydraulic performance augmentation of triangular duct solar air heater using semi‐conical vortex generators: Numerical and experimental study

AbstractThermohydraulic performance augmentation using turbulence promotors is a commonly adopted technique in solar air heater (SAH) applications. This article presents the thermohydraulic performance augmentation of triangular duct SAH using semi‐conical vortex generators (SCVG) using computational fluid dynamics and experimental methodology for various flow Reynolds numbers ranging from 6000 to 21,000. An in‐depth parametric analysis is undertaken to establish the influence of flow attack angle, relative longitudinal pitch, relative transverse pitch and cone diameter of SCVG on the thermohydraulic performance as indicated by the thermohydraulic performance parameter (THPP). The results reveal that the SCVG generates longitudinal vortices and introduces flow impingement zones which significantly affects the flow and heat transfer characteristics of air heaters. Correlations for Nusselt number and friction factor are established, which predicts the performance outcomes with an average error of 6.74% and 4.46%, respectively. The optimal THPP is determined to be 1.74 using artificial neural network model and Bonobo Optimization algorithm. The SCVG produces THPP values well above unity for the entire flow Reynolds number range of 6000–21,000.

Accurate machine-specific reference and small-field dosimetry for a self-shielded neuro-radiosurgical system.

The newly available ZAP-X stereotactic radiosurgical system is designed for the treatment of intracranial lesions, with several unique features that include a self-shielding, gyroscopic gantry, wheel collimation, non-orthogonal kV imaging, short source-axis distance, and low-energy megavoltage beam. Systematic characterization of its radiation as well as other properties is imperative to ensure its safe and effective clinical application. To accurately determine the radiation output of the ZAP-X with a special focus on the smaller diameter cones and an aim to provide useful recommendations on quantification of small field dosimetry. Six different types of detectors were used to measure relative output factors at field sizes ranging from 4to 25mm, including the PTW microSilicon and microdiamond diodes, Exradin W2 plastic scintillator, Exradin A16 and A1SL ionization chambers, and the alanine dosimeter. The 25mm cone served as the reference field size. Absolute dose was determined with both TG-51-based dosimetry using a calibrated PTW Semiflex ion chamber and measurements using alanine dosimeters. The average radiation output factors (maximum deviation from the average) measured with the microDiamond, microSilicon, and W2 detectors were: for the 4mm cone, 0.741 (1.0%); for the 5mm cone: 0.817 (1.0%); for the 7.5mm cone: 0.908 (1.0%); for the 10mm cone: 0.946 (0.4%); for the 12.5mm cone: 0.964 (0.2%); for the 15mm cone: 0.976 (0.1%); for the 20mm cone: 0.990 (0.1%). For field sizes larger than 10mm, the A1SL and A16 micro-chambers also yielded consistent output factors within 1.5% of those obtained using the microSilicon, microdiamond, and W2 detectors. The absolute dose measurement obtained with alanine was within 1.2%, consistent with combined uncertainties, compared to the PTW Semiflex chamber for the 25mm reference cone. For field sizes less than 10mm, the microSilicon diode, microDiamond detector, and W2 scintillator are suitable devices for accurate small field dosimetry of the ZAP-X system. For larger fields, the A1SL and A16 micro-chambers can also be used. Furthermore, alanine dosimetry can be an accurate verification of reference and absolute dose typically measured with ion chambers. Use of multiple suitable detectors and uncertainty analyses were recommended for reliable determination of small field radiation outputs.

2585: Commissioning of a novel 3 mm diameter cone for the ZAP-X system using a microSilicon detector

2585: Commissioning of a novel 3 mm diameter cone for the ZAP-X system using a microSilicon detector

Experimental and numerical investigation of transpiration cooling with gradient porosity layout for the thermal protection of nose cone

Transpiration cooling with liquid phase change has been widely regarded as one of the most promising thermal protection technology for aerospace vehicles. However, when applied to the nose cone with small curvature radius, cooling failure may occur due to the extreme high heat flux and pressure at the stagnation point. In order to deal with this issue, a wedged-shaped nose cone structures with a gradient porosity layout is designed in this work to optimize the coolant distribution in the porous nose cone, and the corresponding transpiration cooling performance with liquid phase change is experimentally and numerically investigated. At last, to meet the thermal protection requirements under different flight conditions as best as possible, an orthogonal experiment and fuzzy gray analysis were carried out to optimize the particle diameter, porosity layout and division interval of the porous nose cone with gradient porosity layout, taking a specific flight condition as an example. The results obtained in this work showed that gradient porosity layout can significantly improve the cooling efficiency at the stagnation point and the temperature uniformity on the outer surface. The porosity has the highest impact on the cooling performance, while the division interval has little impact. By optimizing, the cooling efficiency at the stagnation point can reach 74.5%, and the maximum temperature difference is less than 500K.

Utilization of hydrogen-diesel blends for the improvements of a dual-fuel engine based on the improved Taguchi methodology

A three-dimensional computational fluid dynamics model (CFD) of the diesel engine cylinder was developed using CONVERGE 3.0 software and a chemical reaction mechanism including 172 reactions and 62 components was developed using the CHEMKIN program. Then, the effects of nozzle diameter and spray cone angle on in-cylinder pressure, temperature, HC emission, NOx emission and soot emission of the hydrogen-diesel dual-fuel engine were investigated. Lastly, multi-objective optimization of HES, CR, nozzle diameter and spray cone angle were also carried out using Taguchi methodology. Analysis of variance and signal-to-noise ratio were performed using Minitab software. The results showed that higher in-cylinder pressure, temperature and NOx emission could be obtained with the decreasing nozzle diameters. But HC and soot emissions showed the opposite trend. Using the smaller spray cone angle was more favorable for in-cylinder pressure, temperature, HC, and NOx emissions. However, the small spray cone angle results in large amounts of soot emission. In addition, the factors that had the greatest impact on in-cylinder pressure, temperature, HC emission, and soot emission were all CR. And the factor that had the greatest impact on NOx emission was HES. This work provides a feasible technical approach to improve the marine diesel engine parameters.

Evolution rules for cathode erosion and corresponding arc behaviour in tungsten inert gas welding

Cathode erosion is a serious problem in long hours of Tungsten Inert Gas (TIG) welding. The evolution of electrode end shape and corresponding arc behaviour was studied at different welding currents and cathode parameters. The results illustrate that slow erosion, shedding, and expansion are three typical erosion modes. Slow erosion is an inevitable mode, causing the arc root width ( Ra) and arc diameter ( Rb) to slowly increase by 2.1% and 2.6%, respectively. With the increasing welding current or the decreasing cone angle and diameter, Ra and Rb are increased in shedding mode by 6.3% and 1.0%, respectively. Expansion appears when the electrode end has a truncated cone shape, causing gradual decrease of 5.7% and 2.3% in Ra and Rb, respectively.

Effect of mixing chamber structure on the performance of adjustable ejector

The study employs numerical simulation method to analyze performance of an adjustable ejector, with a specific focus on the influence of the structure dimension of mixing chamber. R41/R1234yf refrigerant is used as the working medium in the study. The primary and secondary flow inlets are set at the pressure of 1.4 MPa and 0.2 MPa, respectively, along with temperature of 353.15 K and 288.15 K corresponding. The outlet pressure of the ejector is 0.3 MPa. The simulation results show that optimal mixing chamber diameter within a range from 14.7mm to 18.7mm exists for obtaining peak adjustable ejector performance. Maximum entrainment ratio of 0.59 is obtained when cone diameter ratio is 65% and diameter of the mixing chamber is 15.7mm. Furthermore, the optimal mixing chamber length within range from 24mm to 220mm exists for obtaining peak adjustable ejector performance. Maximum entrainment ratio of 0.624 is obtained when cone diameter ratio is 76% and length of the mixing chamber is 88 mm. Therefore, it is crucial during designing process of the mixing chamber to ensure the complete fluid mixture and minimal flow resistance.

Multi-Objective Optimization of a Long-Stroke Moving-Iron Proportional Solenoid Actuator.

In this study, the performance of a long-stroke moving-iron proportional solenoid actuator (MPSA) was improved by combining numerical simulations and experiments. A finite element model of the MPSA was developed; its maximum and mean relative absolute errors of electromagnetic force were 4.3% and 2.3%, respectively, under typical work conditions. Seven design parameters including the cone angle, cone length, depth of the inner hole of the coil skeleton, cone width of the armature, inner cone diameter, and initial position of the moving-iron core were selected for developing the model, and the coefficient of the variation in electromagnetic force, nominal acceleration, 95% of the maximum stable output electromagnetic force, and corresponding response time were used as the performance indicators. The constraint relation between each performance indicator and the influence of each design parameter on the performance indicators were revealed using the uniform Latin hypercube experiment design, correlation analysis, and the main effect analysis method. A multi-objective optimization mathematical model of the MPSA was developed by combining traditional surrogate and machine learning models. The Pareto solution set was obtained using the nondominated sorting genetic algorithm II (NSGA-II), and three decision schemes with different attitudes were determined using the Hurwicz multi-criteria decision-making method. The results showed that a strong contradiction exists among the 95% of the maximum stable output electromagnetic force and its corresponding response time and the coefficient of the variation in electromagnetic force. The cone angle considerably influenced the performance indicators. Compared with the initial design, the coefficient of the variation in electromagnetic force was reduced by 54.08% for the positive decision, the corresponding response time was shortened by 15.65% for the critical decision, and the corresponding acceleration was enhanced by 10.32% for the passive decision. Thus, the overall performance of the long-stroke MPSA effectively improved.

Dominant factors in MiniCone, CPT and pile correlations: A data‐based approach

AbstractThe cone penetration test (CPT) contributes to the design and analysis of piles regarding geometry, installation effect, and pile capacity (shaft and toe resistance). MiniCone, as an alternative to CPT sounding, has been used to carry out field and laboratory investigations by physical modeling. More tests can be practically carried out through light equipment and small soil mass, involving fewer errors caused by boundary conditions. Furthermore, it can be used for in situ testing, such as quality control, assessment of ground improvement, and subgrade characterization. A database comprising MiniCone and CPT records in field and physical modeling is proposed with a variety of cone diameters. The case study records in the database have been obtained from 140 tests compiled from data from 26 sources. The sources include the results of 20 physical modelings and field data from six sites in 10 countries. The data comprise MiniCone and CPT cone tip resistance (), and sleeve friction (). The different cones are used in sandy, silty sand, and clayey soils via simple chambers (1 g), calibration chambers, and frustum confining vessels. In addition, correlations were found in penetration records in terms of physical modeling types, cone diameters, penetration rates, and soil densities. Moreover, and are related to capacities of pile toes and shafts using proper correlation coefficients less than unity, respectively. Correlations and dominant factors in geotechnical practice between MiniCone, CPT, and pile have been reviewed and discussed.

Effect of double-layer filter cartridge with an inner cone on the pulse-jet cleaning performance of cartridge dust collectors

The double-layer filter cartridge with an inner cone was designed to improve the pulse-jet cleaning performance of the filter cartridge. The flow field and pressure variation of the double-layer filter cartridge were investigated with the help of numerical simulations. The pressure at the inner wall of the filter cartridge was explored by varying three parameters: the height of the cone (h), the diameter of the cone (D) and the distance between the top of the inner cone and the baffle (H). The results showed that for conventional filter cartridge, influenced by the angle of the pulse-jet, the airflow got sufficiently expanded after the pulse-jet airflow reached the middle of the filter cartridge, and the pressure at the top of the filter cartridge was slight. It was found that the cone diameter and the distance between the top of the inner cone and the baffle had a significant effect on the pressure of the inner wall of filter cartridges, with the distance between the top of the inner cone and the baffle had the most excellent effect and the height of the cone had the slightest effect. Compared with conventional filter cartridges, the peak pressure at measurement point O1 of the optimized double-layer filter cartridge (h = 120 mm, D = 160 mm, H = 0 mm) was increased by 543.3%. The coefficient of variation (C.V.) of the pressure at the inner wall of the outer filter cartridge was significantly reduced, indicating that the pulse-jet cleaning effect of the optimized double-layer filter cartridge was significantly improved. This study can provide theoretical support to reveal the mechanism of pulse-jet cleaning of double-layer filter cartridges and technical support to optimize the design of double-layer filter cartridges.

Poster Session: Eliciting Color Percepts over Extended Fields through Cone-by-Cone Stimulation.

Purpose Human color vision is informed by the relative activations of the long-, medium-, and short-wavelength sensitive cones. We have developed a display that can produce a variety of color sensations using only a single wavelength of light, by programming the activity levels of the three cone types at population scales. Methods With an Adaptive Optics Scanning Laser Ophthalmoscope, we image the retina at 840 nm over a 0.9° x 0.9° field and track the eye's fixational motion in order to deliver discrete microdoses of 543 nm light to ~2500 individual cones per frame. Using each cone type's spectral sensitivity to 543 nm, we can recapitulate the relative activations consistent with colors that are distinct from the stimulating laser, resulting in percepts of uniform colored squares that appear stable in the world. Results Using stimulation from only 543 nm light, we can elicit color percepts ranging from green to red-orange in 2 subjects who have cone spectral types classified in a region of their retina. Additionally, we find through color matching data that the distinct color percepts are lost for intentional misdeliveries that exceed 30% of the cone diameter in both subjects. Conclusions These results demonstrate our system's ability to track the retina at high speed, stimulate with cone-level precision, and generate color percepts by directly programming the activity of the human cone mosaic. These technical capabilities provide a novel platform for studying color vision.

Commissioning of Aktina SRS cones and dosimetric validation of the RayStation photon Monte Carlo dose calculation algorithm

Clinical implementation of SRS cones demands particular experimental care and dosimetric considerations in order to deliver precise and safe radiotherapy to patients. The purpose of this work was to present the commissioning data of recent Aktina cones combined with a 6MV flattened beam produced by an Elekta VersaHD linear accelerator. Additionally, the modelling process, and an assessment of dosimetric accuracy of the RayStation Monte Carlo dose calculation algorithm for cone based SRS was performed. There are currently no studies presenting beam data for this equipment and none that outlines the modelling parameters and validation of dose calculation using RayStation’s photon Monte Carlo dose engine with cones. Beam data was measured using an SFD and a microDiamond and benchmarked against EBT3 film for cones of diameter 5–39 mm. Modelling was completed and validated within homogeneous and heterogeneous phantoms. End-to-end image-guided validation was performed using a StereoPHAN™ housing, an SRS MapCHECK and EBT3 film, and calculation time was investigated as a function of statistical uncertainty and field diameter. The TPS calculations agreed with measured data within their estimated uncertainties and clinical treatment plans could be calculated in under a minute. The data presented serves as a reference for others commissioning Aktina stereotactic cones and the modelling parameters serve similarly, while providing a starting point for those commissioning the same TPS algorithm for use with cones. It has been shown in this work that RayStation’s Monte Carlo photon dose algorithm performs satisfactorily in the presence of SRS cones.

Effect of fertilization on Pinus pinea cone to seed and kernel yields

Stone pine (Pinus pinea L.) is a species of economic interest mainly due to its pine nuts, the most expensive nut in the world. Despite the high value of pine nuts, cones are mainly harvested from unmanaged forests. Therefore, research and its applications are needed to develop nutritional management techniques among other cultivation practices intened to boost production. This study evaluated the effect of fertilization on cone production and quality (cone weight and size, number of seeds and kernels, and health status), which in turn may affect cone to seed and cone to kernel yields. Fertilization consisted of two applications of macro and micronutrients in two adult plantations twice in the growing season (in spring and fall). Morphometric variables, cone production per tree and cone health were evaluated during two years after fertilization. Fertilization effect on cone production was positive and significant in both years, with variations between years. Most of the morphometric variables were positively impacted by fertilization, including cone diameter (3.5% increase), kernel weight and length (7.7% and 2.7% increase, respectively), and total seed and kernel weight per cone (20.9% and 18.6% increase, respectively). Fertilized stone pine trees increased production and quality of cones, seeds and kernels, but did not increase cone to seed or kernel yields. However, fertilization increased type II seed damage by 45.4% and 18.9% in 2020 and 2021, respectively. The results obtained in this research may help producers adopt cultural practices to boost pine nut production.