Commercial Program Research Articles

Effect of landraces on Musa micropropagation

This work aimed at assessing the performance of two landraces of Musa spp in micropropagation. Tissues from Owom and Efol were sterilized by soaking the explants in 70 % ethanol for 30 sec, 8 % NaOCl for 5 min, 5 g/L benlate for 5 min, and in 1.2 g/L HgCl2 for 10 min before being thoroughly washed with distilled water. Tissue exposure to U. V. light for 5 min was done before they were cultured in a shooting MS-based culture medium supplemented with 5.00 mg/L concentration of 6-Benzylaminopurine, and later to a rooting MS-based culture medium supplemented with indoleacetic acid (IAA) of 2.00 mg/l concentration. Data were collected on number of shoots, shoot height, shoot’s health, days to rooting, root number, and root length. The result from shooting medium showed that the plants’ heights were highly significantly different at P ≤ 0.01, with Owom producing marginal mean heights of 3.59 cm and 5.05 cm at 3 and 5 weeks respectively, after initiation. A very high significant difference was observed with plant health at P ≤ 0.001 whereby Owom landrace reduced in health status as the week increased, unlike Efol which increased in health status across the weeks. For rooting medium, significant differences at P ≤ 0.05 for days to rooting, root length, health performance, and plant height were observed. While high significant difference was observed for the number of roots at P ≤ 0.01. Owom performed significantly better than Efol and has shown value for commercial production and breeding programs.

Use of excised ovaries for oocyte recovery by ultrasound guided follicular aspiration – Validation of an experimental model for research purposes in live mares ovum pick up

Ovum pick-up (OPU) by transvaginal ultrasound guided follicle aspiration in mares is a common assisted reproductive technique used for oocyte recovery and in vitro production of horse embryos. There has been relatively little research into the factors influencing oocyte recovery in OPU from live mares. The objective of this study was to compare oocyte recovery and morphology of ultrasound-guided follicle puncture and aspiration in live mares and in postmortem excised ovaries, in order to validate an experimental model for research purposes of the efficiency of OPU in mares. Data from OPU performed in 12 mares from a commercial program (follicle numbers, oocyte recovery and oocyte morphology) were compared to that obtained from ultrasound-guided follicle puncture of 13 postmortem excised ovaries from slaughtered mares processed within 2 h of slaughter. In both groups, the OPU was performed by the same operator using the same equipment and OPU technique. The recovered oocytes per aspirated follicle was higher (P < 0.05) in the postmortem group (105/166, 63.2 %) than in live mares (138/261, 52.9 %). There was more (P < 0.05) expanded cumulus oocyte complexes in the postmortem than in the live mares (18 % vs. 2.9 %). Several oocytes (5 oocytes from 81 aspirated follicles) were found in the leaked fluid which overflowed during follicle flushing of postmortem ovaries. In conclusion, the higher recovery rate obtained in the excised ovaries and the finding of oocytes in the leaked fluid during OPU, suggests that there is still room for improvement in the in vivo OPU technique. Utilizing postmortem excised ovaries could offer an alternative for further research into factors affecting oocyte recovery and oocyte leakage during OPU procedures.

Pedigree reconstruction based on target sequencing in Pacific white shrimp Litopenaeus vannamei

Litopenaeus vannamei is one of the most economically productive species in aquaculture. It accounts for about 80% of the world's mariculture production of shrimp. Genetic selection of shrimp is mainly based on family selection. Therefore, accurate pedigree information is essential to ensure the reliability of estimated genetic parameters and the selection of the best broodstock. Recent advances in molecular breeding have facilitated molecular pedigree reconstruction based on SNPs and improved the accuracy of selection. However, breeding populations of aquatic species tend to be large. Therefore, a high-throughput and cost-effective method was needed for the commercial application of parentage assignment. In this study, we developed a low-density SNP panel based on target sequencing. A total of 200 amplicons, evenly distributed across the genome, were captured by multiplex PCR and sequenced by next-generation sequencing. Genotyping of 320 individuals in four ponds including multiple families identified 1,169 SNPs. Based on these SNPs, two softwares including Sequoia and PaternityT were used to reconstruct the sibling information. Consequently, a total of 39 families were accurately identified, and the results of the two software programs were highly consistent. Analysis based on different numbers of amplicons showed that at least 50 amplicons were required for accurate assignment. The identification result was also validated by principal component analysis and phylogenetic analysis. With the development of NGS technology, thousands of individuals could be genotyped with high throughput and low cost, making the method developed in this study affordable for parentage assignment in commercial breeding program. Meanwhile, the low-density SNP panel also has high value and prospects for application in shrimp genetic research.

Multi-objective optimization through desirability function analysis on the crashworthiness performance of thermoplastic/thermoset hybrid structures

This paper aims to optimize the crashworthiness capability of glass-reinforced epoxy composites (GFRE) over wrapped polyvinyl chloride (PVC) circular tubes with cutouts. The intended tubes were prepared by a wet wrapping method; then subjected to quasi-static axial compression. To compute crashworthiness indications, three design parameters, each at three levels, were used. The design parameters are the hole diameter (d), the hole's number (n), and the hole position (L). A few runs were accompanied by the L9 orthogonal array based on the Taguchi technique. With the lowest initial peak crash force (Fip) and the largest absorbed energy (U), the optimal parameters were found. Furthermore, the main effect, signal-to-noise ratio (S/N), as well as the analysis of variance (ANOVA), have been studied using the commercial software program MINITAB 18. Furthermore, to optimize the process parameters in terms of the crashworthiness indicators, desirability function analysis (DFA) was applied. Lastly, tests for confirmation were performed to verify the predicted values in light of the experimental results and compare them with the intact tubes. Regarding the single optimization, the optimum Fip tube is smaller than the intact PVC tube and intact hybrid tube, at 24.01 and 72.85 %, respectively. Nonetheless, the optimal U was 21.43 % lower than the intact hybrid tube and 152.75 % greater than the intact PVC tube. While, for Fip and U, the multi-objective optimization specimen achieves 5.13 and 70.02 % greater than the intact PVC tube. But it was 62.44 % and 47.14 % less than what the intact hybrid tube had accomplished.

Space surgery: a SAGES' white paper.

Space travel is experiencing a renaissance with expanding commercial and international efforts. Space surgery will have growing relevance as mission frequency and distances increase beyond low Earth orbit. This white paper from the SAGES Space Surgery Task Force raises awareness among the SAGES membership regarding the challenges and opportunities surrounding this emerging field that anticipates surgical care in the most extreme, austere environments. Innovation in technology and preventive medicine principles will enhance the effectiveness of space surgical care when the need arises. The impact of advancements in space and terrestrial medicine to support space exploration indicates the need for a surgeon to oversee medical/surgical invasive treatment to ensure astronaut health and mission success. Advanced technology, including semi- and autonomous robotic systems, may be a preferred way to deliver this care in the foreseeable future. There is currently a need to develop training curricula and flight-compatible supplies and technology for physicians that deliver surgical care to this special patient population. The protocols and technology developed to address the unique challenges of space travel will provide value for care in space as well as in extreme, austere terrestrial environments on Earth. Space surgery will continue to evolve as commercial and government programs explore further into space. The SAGES Space Surgery Task Force is favorably positioned to significantly contribute to addressing some capability gaps in delivering surgical care in space.

Validation of Hand Grading Technique of Corpora Lutea in Embryo Recipient Cows

The success of embryo transfer in cattle may depend on several factors. The blood progesterone level of the embryo recipient would be one of the main factors secondary to the size and quality of the corpus luteum. Per-rectal palpation and by-hand grading of corpora lutea have been practiced routinely, even under commercial embryo transfer programs in cattle. This experiment aimed to evaluate the accuracy of the per-rectal hand grading technique of mid-phase corpora lutea in embryo recipient cows. A group of healthy cows (Friesian× Jersey, n=25), which had been selected as recipient animals with the special consideration of reproductive history in an embryo transfer program, was used in this study. Estrous of those animals were synchronized using a standard progesterone intravaginal devise-PGF2α protocol. Conven-tional evaluation and grading of corpora lutea were conducted at the per-rectal hand grading as 'A', 'B', 'C' and 'Cystic' (If diameters; &lt; 1cm=C, 1-1.9cm=B, 2-2.5cm= A, &gt;2.5cm= Cystic). In this study, the accuracy of those hand-grading techniques was evaluated using ultra-sound scanning technology on the same day. Identification accuracy of grades C, B, A, and Cysts in hand grading technique was 45%, 56%, 67%, and 50%, respectively. The average accuracy in the hand grading technique was 52%, and identification accuracy as suitable (A or B) corpora lutea for embryo transfer was 76%. Results raised the 24% probable loss of embryo transferrable recipients due to the hand-grading technique. Further, 8% of unsuitable cows can be selected as embryo recipients due to the practice of hand-grading techniques at embryo transfer programs. Although higher accuracy is a characteristic of the hand grading technique, the technology causes considerable loss due to inaccurate selection probability of recipients at embryo transfer programs.

Optimising a digitally delivered behavioural weight loss programme: study protocol for a factorial cluster randomised controlled trial

BackgroundDigitally delivered weight loss programmes can provide a convenient, potentially cheaper, and scalable treatment option for people who may need to lose weight. However, outcomes are often inferior to in-person interventions in the long-term. This trial will use principles from the Multiphase Optimisation Strategy (MOST) framework to test whether it can enhance the effectiveness of a commercial digital behavioural weight loss programme. This trial aims to identify an optimised combination of four intervention components to enhance weight loss over a 24-week period. We will also explore which components contribute to improvements in participant retention and engagement with the programme.MethodsApproximately 1400 adults with a BMI > 21 kg/m2 will be enrolled and randomised to one of 16 experimental conditions in a 24 factorial cluster design. The trial will test four intervention components: an introductory video call with the health coach, drop-in webchat sessions with the health coach, goal setting statements, and food diary review and feedback. All participants will receive the core digital behavioural weight loss programme and up to four new intervention components. Participation in the trial will last for 24 weeks. The primary outcome will be weight change at 16 weeks. Other outcomes, measured at 4, 16, and 24 weeks, include programme drop-out and engagement (number of interactions with the three main app functions). Fidelity and acceptability will be assessed using data on component adherence and self-report questionnaires. Decision-making for the enhanced programme will be based on components that contribute to at least a minimal improvement in weight loss, defined as ≥ 0.75kg, alone or in combination with other components.DiscussionThe factorial design is an efficient way to test the efficacy of behavioural components alone, or in combination, to improve the effectiveness of digital weight loss programmes. This trial will test the implementation of the MOST framework in an industry setting, using routinely collected data, which may provide a better way to refine and evaluate these types of interventions in a model of continuous service improvement.Trial registrationTrial registration: ISRCTN, ISRCTN14407868. Registered 5 January 2024, 10.1186/ISRCTN14407868.

Controllable manipulation of surface waves via a ferromagnetic elastic metasurface

In this paper, we study the propagation of surface waves on an A-shape metasurface, whose structure of the unit-cell is composed regularly of an A-shape surface column (made of steel), a thin magnetorheological plate and a soft thick rubber base. On the basis of the commercial program COMSOL Multiphysics, finite element method (FEM) analyses are carried out. The localization of elastic waves surrounding the surface allows surface waves to be distinguished among various complex wave modes. By adjusting the geometry, the A-shape surface column can be transformed from snowflake to A-shape. Owing to the C3v symmetry system, a Dirac cone of surface wave is observed in a snowflake metasurface. When the surface column changes to A-shape, the C3v symmetry is broken, making the Dirac cone vanish and a new band gap of surface waves arise. The band gap can be opened or closed by changing a geometric parameter, which determines the shape of the surface column changing from gadarene A-shape to snowflake or even upturned A-shape. Furthermore, we discover that although the topological phases of the gadarene A-shape and upturned A-shape metasurfaces are opposite, they share overlapped band gaps. Based on this phenomenon, we design a topological insulator for surface waves, whose super-cell is composed of gadarene A-shape units and upturned A-shape units. Through the calculation of the super-cell band structure, we observe the topologically protected interface states (TPISs). Subsequently, we design several waveguides whose paths are controllable. Up to now, most of the existing metasurfaces are made of passive materials, whose properties cannot be adjusted in real time, making them inconvenient for engineering applications when external conditions are changed. Therefore, we use tunable magnetorheological elastomer (MRE) to control the properties of the topological insulators. The stiffness of the surface layer can be converted by applying a magnetic field, which makes the topological metasurface controllable. These intelligent topological insulators may find important applications in the design of surface acoustic wave (SAW) devices.

고전검사이론(Classical Test Theory)의 C코드 구현방법 연구

The purpose of this paper is to implement classical test theory (CTT) as C code to obtain statistical analysis, item difficulty, and item discrimination used for the item analysis, and to verify the performance by comparing it with the existing commercial TestAn program. Test theory for item evaluation is divided into CTT and item response theory (IRT). Recently, the IRT has been widely used, but CTT is also used as an item analysis theory along with IRT. In this paper, CTT was directly implemented as C code, compared and analyzed the difference between the results calculated using the actual examinee’s answer sheet and the commercial program for the accuracy of the program calculation result. The formula for CTT was implemented as C language code, and the code was presented so that it could be changed and utilized in various platforms such as Android, Linux, dotNet, etc. Therefore, it is expected that it will be highly utilized in the industrial field that builds an evaluation system.

Points of inflection of special eigenvalue functions as indicators of stiffness maxima/minima of proportionally loaded structures

The stiffness of a proportionally loaded structure may continuously increase or decrease. As a special exception, it may be constant. On the other hand, an initially stiffening (softening) structure may turn into a softening (stiffening) structure. At the load level of such a change the stiffness of the structure attains an extreme value. The task of this work is to present mathematical conditions for these load levels. Lack of them represents a void in the pertinent literature. The practical significance of the aforementioned changes is the one of indicators of the mechanical behavior to be expected after their occurrence. The second and the last author have recently presented a condition for the load level at which the stiffness of a proportionally loaded structure becomes a minimum value. It is given as d2(ℜ(χ1(λ)))/dλ2=0, representing the condition for a point of inflection of the real part of a complex eigenvalue function χ1(λ), where λ denotes a dimensionless load parameter. The underlying linear eigenvalue problem has two indefinite coefficient matrices, which is a necessary condition for complex regions of eigenvalue functions. These matrices are established with hybrid elements, available in a commercial finite element program. In the present work, d2(χ1(λ))/dλ2=0 is shown to be the condition for the load level at which the stiffness of a proportionally loaded structure attains a maximum value. The eigenvalue function concerned has no complex region. It is also shown that the displacement elements, which are the basis for their extension to the employed hybrid elements, are unable to indicate the load level at an extreme value of the stiffness.

Comparison of Three Commercially Available, AI-Driven Cephalometric Analysis Tools in Orthodontics.

Background: Cephalometric analysis (CA) is an indispensable diagnostic tool in orthodontics for treatment planning and outcome assessment. Manual CA is time-consuming and prone to variability. Methods: This study aims to compare the accuracy and repeatability of CA results among three commercial AI-driven programs: CephX, WebCeph, and AudaxCeph. This study involved a retrospective analysis of lateral cephalograms from a single orthodontic center. Automated CA was performed using the AI programs, focusing on common parameters defined by Downs, Ricketts, and Steiner. Repeatability was tested through 50 randomly reanalyzed cases by each software. Statistical analyses included intraclass correlation coefficients (ICC3) for agreement and the Friedman test for concordance. Results: One hundred twenty-four cephalograms were analyzed. High agreement between the AI systems was noted for most parameters (ICC3 > 0.9). Notable differences were found in the measurements of angle convexity and the occlusal plane, where discrepancies suggested different methodologies among the programs. Some analyses presented high variability in the results, indicating errors. Repeatability analysis revealed perfect agreement within each program. Conclusions: AI-driven cephalometric analysis tools demonstrate a high potential for reliable and efficient orthodontic assessments, with substantial agreement in repeated analyses. Despite this, the observed discrepancies and high variability in part of analyses underscore the need for standardization across AI platforms and the critical evaluation of automated results by clinicians, particularly in parameters with significant treatment implications.

Socio-Economic Policy and Youth Unemployment in Nigeria: An Assessment of Ekiti State Youths for Commercial Agriculture Development Programme (YCAD)

Socio-Economic Policy and Youth Unemployment in Nigeria: An Assessment of Ekiti State Youths for Commercial Agriculture Development Programme (YCAD)

A regression waist level defined for 3D body scans

Finding waist levels on 3D scans is challenging because measurement programmes measure bodies non-invasively in a digital environment. However, most body measurement standards require interactions between measurers and subjects, such as bending and touching, to find accurate waist levels. Research shows that the accuracy of commonly used waist substitutes, such as the small of the back and the narrowest from the front view, depends on 3D scans’ body shape and size, making the waist substitutes not ideal as generic ways of locating 3D waist levels. This research aimed to study the relationship between 3D waist levels found by domain experts and digital landmark coordinates identified by commercial body measurement programmes to develop regression models that predict waist levels on 3D scans. The developed regression model was tested and found to perform better than the selected waist substitutes. It assists the standardization process of extracting waist-related body measurements from 3D scans.

Hospital strategies in commercial episode-based reimbursement.

To understand hospitals' approaches to spending reduction in commercial episode-based payment programs and inform incentive design. Qualitative arm of an explanatory sequential mixed-methods study involving semistructured interviews with hospital leaders participating in a statewide quality improvement collaborative with novel episode-based incentive payments introduced by the state's largest commercial payer. We recruited 21 leaders from 8 purposively selected, diverse hospitals with both high and low performance. Video teleconference-based interviews followed a standardized protocol and addressed 4 domains: choice of clinical condition for evaluation, strategies for episode spending reduction, best practices for success in earning incentives, and barriers to achievement. Rapid qualitative analysis with purposeful data reduction was employed to generate a matrix of key themes within the study domains. Strategies were similar between high- and low-performing hospitals. When selecting conditions, some hospitals focused on areas of underperformance, aiming for improvement opportunities, whereas others chose conditions already achieving highest efficiency. Many tried to synergize with other ongoing improvement initiatives and clinical areas with established leaders and champions. Key strategies included data-driven improvement, care standardization, and protocol dissemination. Best practices for success included readmission prevention and postacute care spending containment. The findings highlighted hospitals' most common strategies and approaches, providing several insights into optimal design of commercial episode-based incentives: They must be lucrative enough to earn attention or consistent with larger federal programs; hospitals need opportunities to succeed through both improved performance and sustained excellence; and programs may incur malalignment between hospitals and credentialed physicians.

New maize inbred development method I: Inter‐heterotic group composite and tester choice

AbstractCurrent maize (Zea mays L.) breeding methods and the limited germplasm infusion and mixing may slow the rate of genetic gain in the future. Using inter‐heterotic group composites for maize inbred development has been questioned because of the issue of choosing appropriate testers. However, three observations can be revisited to facilitate the exploration of alternative methods. First, since the adoption of single‐cross hybrids and the establishment of heterotic groups, the amount of heterosis has only been increasing slightly. Second, genomic analysis indicated the frequencies of the favorable alleles had significantly increased after a century's breeding. Third, the divergence of maize heterotic groups was preceded by the merging of landraces and diverse inbreds, after which three major heterotic groups were established. The objective of this study was to design different scenarios to generate inter‐heterotic group composites and evaluate their usefulness in the commercial breeding program. We investigated two methods: the inter‐heterotic group composite method (termed as super population [SupPop]) and the modified SupPop method (ModiSP, that is, backcrossing SupPop lines with elite inbreds). The results showed that the best scenario for the SupPop method was to use the SupPop inbreds to cross with a tester from the B14 group. When all four heterotic groups were mixed, the favored tester was from stiff stalk. However, ModiSP showed a higher chance of producing the best yield performance. These empirical results suggest that solutions can be proposed to identify the testers so that using inter‐heterotic group composites for inbred development can be considered.

Contribution of advanced windows and façades to buildings decarbonization: A comprehensive review

On a global level the building sector consumes about 45.00% of energy consumption, contributes about 40.00% to emission, uses 30.00% of water and impacts the environment by generating 30.00% of waste. Although windows are important components of a building that provide natural lighting and ventilation and establish necessary contact with the external environment necessary for healthy indoor ambient, they permit entry of undesirable solar heat in summer and allow escaping heat from the indoor ambient in cold seasons, which aggravate the building needs for energy and increase its contribution to atmospheric emissions. The present investigation provides a review on research, development, and applications of advanced windows in the building sector. The introduction highlights the importance and contribution of advanced glazing technology to improving energy, comfort, and thermal performance of buildings. The review includes natural illumination and ventilation, thermal comfort and discusses the effects of window to wall ratio on natural illumination and ventilation of windows and façades. The review also covers recent developments in glazed windows and façades including performance enhancements by using reflective solar films, vacuum glazing, windows with filling materials, windows with water flow, window with phase change material, window with stagnant inert gas filling, ventilated windows and façades and windows with aerogel. A special section was also included on smart glazing for windows and façades showing the new tendencies and applications in the building industry. Since commercial programs and open access codes are handy tools for simulation and performance calculations a section is dedicated to these codes. The conclusion section contains the most relevant conclusion of the review as well as future trends in research and developments in the area. The topics included in this review can be helpful for experienced and young researchers, practicing engineers and general readers interested in windows and façades.

Characterizing stay-green in barley across diverse environments: unveiling novel haplotypes

Key messageThere is variation in stay-green within barley breeding germplasm, influenced by multiple haplotypes and environmental conditions. The positive genetic correlation between stay-green and yield across multiple environments highlights the potential as a future breeding target.Barley is considered one of the most naturally resilient crops making it an excellent candidate to dissect the genetics of drought adaptive component traits. Stay-green, is thought to contribute to drought adaptation, in which the photosynthetic machinery is maintained for a longer period post-anthesis increasing the photosynthetic duration of the plant. In other cereal crops, including wheat, stay-green has been linked to increased yield under water-limited conditions. Utilizing a panel of diverse barley breeding lines from a commercial breeding program we aimed to characterize stay-green in four environments across two years. Spatiotemporal modeling was used to accurately model senescence patterns from flowering to maturity characterizing the variation for stay-green in barley for the first time. Environmental effects were identified, and multi-environment trait analysis was performed for stay-green characteristics during grain filling. A consistently positive genetic correlation was found between yield and stay-green. Twenty-two chromosomal regions with large effect haplotypes were identified across and within environment types, with ten being identified in multiple environments. In silico stacking of multiple desirable haplotypes showed an opportunity to improve the stay-green phenotype through targeted breeding. This study is the first of its kind to model barley stay-green in a large breeding panel and has detected novel, stable and environment specific haplotypes. This provides a platform for breeders to develop Australian barley with custom senescence profiles for improved drought adaptation.

186 Evaluation of the effects of a Lactobacillus postbiotic product (LumensaM) in medicated and non-medicated nursery pig diets

Abstract Two studies in weanling pigs were conducted to evaluate the effects of a Lactobacillus postbiotic product (LFP; Lumensa, Verdesian Life Sciences, Salt Lake City, UT) in medicated and non-medicated nursery pig diets on performance, daily fecal scores and some fecal microbiome measures. A 2 X 3 factorial factorial design with main effects of in-feed medication (0 vs 55 ppm of Carbadox) and LFP inclusion rate (0, 0.075, or 0.15%) was used in each study. In study 1, LFP in liquid form was added to the treatment diets, and in study 2 LFP in dry form was used in the treatment diets. Each study used 36 pens containing 10 weanling pigs (PIC 800 x 1050; 21 d of age) per pen, and there were 6 pens for each treatment group. A pelleted three-phase commercial nursery feeding program was used. Dry LFP product increased final body weight (BW) linearly (P &amp;lt; 0.05) and tended to improve gain to feed ratio (G:F; P = 0.07) in study 2. Final BW was increased (P = 0.006) in nursery pigs fed medicated diets in study 2 but not in study 1. Feeding the dry LFP in study 2 improved growth performance (P &amp;lt; 0.05) in nursery pigs when they were fed non-medicated diets. In study 1, it was found that feeding LFP tended (P = 0.10) to decrease final BW variability (pen BW CV) on d 42. Daily fecal scores were recorded during both studies, and no treatment effects were observed. During study 2, fresh fecal samples were collected from each pen on d 21 and d 42 for microbial analysis. The Shannon Index was found to be moderately correlated (P &amp;lt; 0.05) to BW results on d 21 and 42 (Study 1, r = -0.31 and 0.19; Study 2, r= -0.49 and 0.27, d 21 and d 42, respectively). It was found that feeding LFP decreased the proportion of Gammaproteobacteria, which includes several Gram-negative pathogens, on d 21 (P &amp;lt; 0.05). In conclusion, feeding LFP to nursery pigs as dry product may increase average daily gain in pigs fed non-medicated diets and decrease BW variability (pen BW CV) when pigs are fed nursery diets containing carbadox. Also, feeding LFP may lead to changes in the fecal microbiome.

Hydrothermal analysis for a slinky-type horizontal borehole heat exchanger equipped with turbulator considering various ground depths

This work critically evaluates hydrothermal behavior inside the slinky-type horizontal borehole heat exchanger with turbulator. The employed turbulator is the spiral twisted tape. The simulations are performed using the finite volume approach in the laminar flow area (Re = 250–400) using a commercial CFD program. Four ground depths (600, 1000, 1400, and 1800 mm) are selected for the proposed heat exchangers, and the outcomes are compared with and without the proposed turbulator. The obtained numerical results demonstrate that in all of the proposed situations, the average Nussel number and heat transfer coefficient grow as the Reynolds number increases. For a given Reynolds number, increasing the depth of the proposed borehole heat exchanger results in a greater heat transfer coefficient. Also, the turbulator-equipped model's outlet temperature values are higher than those of the non-turbulator-equipped model due to the presence of spiral twisted tape. More swirl flows result from this, which speeds up the rate at which heat is transferred from the fluid inside the proposed heat exchanger to the nearby soil. Moreover, the pressure drop increases as the Reynolds number augments, and this tendency is the same for both cases with and without turbulators. Furthermore, the model with 1000 mm depth at Re = 350 has the best thermal performance, and the model with 1400 mm depth is in the second level at Re = 350. The model with 1800 mm depth is attributed to having the lowest thermal performance in all analyzed Reynolds numbers because of the model's more considerable pressure drop. The model with a depth of 1800 mm has the lowest thermal performance at the lowest value of the researched Reynolds number (Re = 250). The models, including 600, 1000, and 1400 mm depths, have thermal performances of approximately 23.53, 11.76, and 8.82 % higher, respectively, than the reference model (1800 mm depth). According to the lowest Reynolds number trends, the model with a depth of 1800 mm has the lowest thermal performance at Re = 400, the maximum value of the analyzed Reynolds number in this case. Compared to the reference model (1800 mm depth), the thermal performance of the other models—including those with 600, 1400, and 1000 mm depths—is roughly 6.67, 11.11, and 26.67 % greater, respectively.

Design and Optimization of Rear Wheel Assembly in All-Terrain Vehicle

Abstract: Suspension is one of the automobile's critical subsystems. Isolating the driver from the shocks of the road is the ultimate purpose. The need of sufficient wheel travel, lateral stability, load transmission, and driver comfort are elements of secondary functions. The study details the design and improvement of an ATV's braking and rear wheel suspension systems. The vehicle was designed under the terms of rules framed by the SAE Organization. The suspension provides the most effective achievable camber, caster, toe, anti-dive, Roll Center, and improvements since it is made for tough terrain. Additionally, there are also calculations, mounting considerations, and shock absorber presented. A prime instance of a commercial software package that studies suspension geometry is Lotus Shark. With the commercial program ANSYS WOKRBENCH, different suspension components are subjected to finite element analysis. All knuckle tests were performed on aluminium alloys 7075 and Hub EN24.