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In order to reduce the development cost of open topping-on structured crochet fabrics and realize the diversified design and three-dimensional (3D) simulation of fabric, the weaving process and principle of this kind of fabric were deeply studied, and the lapping motion and yarn threading motion models of fabric structure were established. Combined with the structural characteristics of fabric, the geometric models of pillar stitch organization, weft lining organization, open topping-on organization, and fringed weft-insertion organization were established under ideal conditions. Through the measurement and analysis of the actual fabric, the number and position of the coil type value points are further determined. The shape transformation of the fringes is realized by combining the random geometric transformation algorithm. This work introduces the structural characteristics and process design method of a typical fabric, and explores the diversified combination of structures, and finally realizes the 3D simulation of fabric with the help of JavaScript and C# computer programming language. The results show that, through 3D simulation technology, we can quickly try different patterns, materials, and color combinations, so as to see the design effect intuitively. This way of virtual display and iterative modification can significantly improve the design efficiency, and greatly reduce the trial and error cost and time consumption, providing an efficient way to find the best design scheme.

Cotton topping is a crucial aspect of cotton production, inhibiting apical dominance in cotton plants. Existing cotton topping machinery often results in over-topping. To address this challenge, the characteristics of manual topping operations were emulated by incorporating bionic principles to analyze the motions involved. Studying the artificial topping action and the trajectory of hand movements led to the design of a bionic topping manipulator and a trajectory-generating mechanism, serving as the core component of the cotton topping device. A flat-bottomed follower disc cam mechanism was used to facilitate the automatic opening and closing of the manipulator. The cam’s working area was divided, its contour curve selected, and the manipulator’s pulling spring’s action point and length determined. Subsequently, parametric equations for the motion trajectory of the bionic topping manipulator were established. Building on the topping mechanism’s working principle, a mechanical model was developed to analyze the swing of cotton plants. The model demonstrates that the displacement at the free end of the stalk was primarily influenced by its length. A lifter was then designed to reduce plant swing amplitude and orderly distribute its top position. The designed prototype of a single-row cotton bionic topping device was tested and verified through orthogonal tests, using operating speed, rotational speed, and topping depth as test factors. The topping rate and over-topping rate served as the indices for testing. The results indicated an average topping rate of 78.67% and an over-topping rate of 8%. This was achieved at a 0.3 m/s operating speed, a 40 r/min rotational speed, and a 110 mm topping depth. Cotton topping devices demonstrated greater effectiveness in minimizing damage to cotton plants, and future research should focus on enhancing topping rates even further. This study provides a theoretical foundation and test data to support the design of cotton topping machinery, guiding future mechanical improvements and agricultural practices.

Background and AimsCotton (Gossypium hirsutum) has indeterminate growth. The growth regulator mepiquat chloride (MC) is used worldwide to restrict vegetative growth and promote boll formation and yield. The effects of MC are modulated by complex interactions with growing conditions (nutrients, weather) and plant population density, and as a result the effects on plant form are not fully understood and are difficult to predict. The use of MC is thus hard to optimize.MethodsTo explore crop responses to plant density and MC, a functional–structural plant model (FSPM) for cotton (named CottonXL) was designed. The model was calibrated using 1 year's field data, and validated by using two additional years of detailed experimental data on the effects of MC and plant density in stands of pure cotton and in intercrops of cotton with wheat. CottonXL simulates development of leaf and fruits (square, flower and boll), plant height and branching. Crop development is driven by thermal time, population density, MC application, and topping of the main stem and branches.Key ResultsValidation of the model showed good correspondence between simulated and observed values for leaf area index with an overall root-mean-square error of 0·50 m2 m−2, and with an overall prediction error of less than 10 % for number of bolls, plant height, number of fruit branches and number of phytomers. Canopy structure became more compact with the decrease of leaf area index and internode length due to the application of MC. Moreover, MC did not have a substantial effect on boll density but increased lint yield at higher densities.ConclusionsThe model satisfactorily represents the effects of agronomic measures on cotton plant structure. It can be used to identify optimal agronomic management of cotton to achieve optimal plant structure for maximum yield under varying environmental conditions.

No practically viable method yet exists to provide minimum shear reinforcements into pretensioned precast hollow-core slab (PHCS) units produced through an automated extrusion method. Subsequently, the web-shear strength of PHCS units with untapped depths greater than 315 mm (12.5 in.) should be reduced in half, according to current ACI 318 shear design provisions. Meanwhile, continuous precast floor construction has been commonly adopted in current practices by using cast-in-place (CIP) topping and/or core-filling concrete. However, shear test results on continuous composite PHCS members subjected to combined shear and negative bending moment are very limited in literature. To this end, this study conducts shear tests of thick composite PHCS members with untapped depths greater than 315 mm (12.5 in.) and various span-depth ratios subjected to negative bending moments, where noncomposite and composite PHCS units subjected to shear combined with positive bending were also tested for comparison purposes. Test results show that flexure-shear strength can dominate the failure mode of continuous PHCS members rather than the web-shear failure, depending on the presence of CIP topping concrete and shear span-depth ratio. In addition, it was also confirmed that the shear strength of composite PHCS members is marginally improved by using a core-filling method under negative bending moment at continuous support, and thus its shear contribution seems not fully code-compliant and satisfactory to that estimated using ACI 318 shear design equations. Keywords: composite action; continuous member; core-filling; flexure-shear; hollow-core slab; negative moment; shear strength; topping concrete; web-shear.

The interaction between noncoding endogenous target mimicry (eTM) and its corresponding microRNA (miRNA) is a newly discovered regulatory mechanism and plays pivotal roles in various biological processes in plants. Tobacco (Nicotiana tabacum) is a model plant for studying secondary metabolite alkaloids, of which nicotine accounts for approximately 90%. In this work, we identified four unique tobacco-specific miRNAs that were predicted to target key genes of the nicotine biosynthesis and catabolism pathways and an eTM, novel tobacco miRNA (nta)-eTMX27, for nta-miRX27 that targetsQUINOLINATE PHOSPHORIBOSYLTRANSFERASE2(QPT2) encoding a quinolinate phosphoribosyltransferase. The expression level of nta-miRX27 was significantly down-regulated, while that ofQPT2and nta-eTMX27 was significantly up-regulated after topping, and consequently, nicotine content increased in the topping-treated plants. The topping-induced down-regulation of nta-miRX27 and up-regulation ofQPT2were only observed in plants with a functional nta-eTMX27 but not in transgenic plants containing an RNA interference construct targeting nta-eTMX27. Our results demonstrated that enhanced nicotine biosynthesis in the topping-treated tobacco plants is achieved by nta-eTMX27-mediated inhibition of the expression and functions of nta-miRX27. To our knowledge, this is the first report about regulation of secondary metabolite biosynthesis by an miRNA-eTM regulatory module in plants.

A martensitic stainless tool steel was remelted by a Pressure Electroslag Remelting (PESR) process with deliberate cancellation of the remelting just before normal hot-topping operation. Enabling evaluation of the ingots melt pool profile, dendrite angle and -spacing, and macro segregation during normal remelting conditions. A longitudinal cross section (500×500 mm) from the top of the cylindrical 500 mm diameter ingot was extracted from its transverse midpoint and macro-etched. Microstructural characterization of the solidification structure was carried out using a combination of light optical microscopy and high-resolution camera images, and macro segregation by optical emission spectroscopy and combustion infrared detection. The results from the ingot cross section were compared with predictions made by the commercially available modelling software package, MeltFlow-ESR™.

Minimally processed fruits are an alternative to add value to products that are difficult to sell, in addition to facilitateconsumer consumption. The objective is to research pulp browning inhibition in a simulated commercialization of minimally processed ‘Monalisa’ apples, stored in a refrigerated environment. After being sanitized with sodium hypochlorite, the apples were cut and immersed in the following treatments: the control being sodium erythorbate (ES) + A (distilled water); ES + FM (cassava starch 3%); ES + AS (3% sodium alginate); ES + AM (6% waxy maize starch) and ES + AP (3% pine nut starch), all together with 1% calcium chloride. Afterwards, 10 slices were placed in a polyethylene tray, wrapped in stretchable PVC film and stored in a refrigerated chamber at 4 ºC ± 1 ºC and relative humidity of 90 - 95%. Phytochemical evaluations were performed at 0, 3, 6 and 9 days of storage. The applied treatments maintained fruit quality. The treatment with cassava starch and pine nut starch were efficient in preserving the darkening of the fruit pulp on day 9. As for the waxy corn starch treatment, the enzyme activity was lower in the period of 0 and 6 days, maintaining quality and delaying darkening. The control sample (ES + A + CC) stood out during the 9-day period, as there was a decrease in the activity of polyphenoloxidase and peroxidase enzymes.

This article presents a development and validation of a method to determine the starting time for hardening concrete flooring mechanically floated using the Dry Shake Topping technique. Until now, an informal method based on shoeprint penetration depth of 3–4 mm into the hardening concrete floor has been used in practice, but it is prone to significant errors. The probe time method described in the literature also has multiple limitations and drawbacks. Currently, there is no scientifically verified method for accurately determining the setting time of concrete mix and its early compressive strength. This gap poses a research problem because incorrect early timing of topping floating leads to further defects in concrete flooring. Through various laboratory, pilot, and technical-scale tests, a new method was developed. According to this method, floating should begin when the penetration depth of the Proctor Compaction Test Apparatus in the concrete mix reaches 4–7 mm. This penetration depth corresponds to the point at which the hardening concrete mix achieves sufficient strength to support the floating equipment while remaining plastic enough to ensure a strong bond between the topping and concrete layers. The article presents correlations between the Proctor Compaction Test results and the early strength of young concrete. It also explains practical on-site application of the method, providing immediate results without the need for interpolation. This method can be applied to any concrete mix intended for use in concrete flooring.

Industrial applications that require steam for their end-use generally utilize steam boilers that are typically oversized, citing operations flexibility. Similarly, gas turbine-based power plants corroborate a gas turbine system that may eventually relieve the usable exhaust into the atmosphere. This study explores the economic and technical feasibility of a topping cycle combined heat and power (CHP) system. It does so by leveraging a partially loaded boiler or gas turbine by increasing its unused load to generate steam and heat for subsequent usage. To this end, a decision support tool (COGENTEC) was developed, which emulates a given facility’s boiler or gas-turbine system, and its operational parameters with the application of steam turbines. The tool provides necessary insights into the most appropriate parameters that enable a CHP system to be technically and economically advantageous. Based on input variables such as boiler-rated capacity, steam pressure, steam temperature, and existing boiler load, among others, COGENTEC designs a topping cycle CHP system to inform a user whether this system is feasible in their facility or not. If applicable, the tool assists the user to realize the point of break-even (fuel cost incurred and cost savings) at the desired steam flow rate. It also conducts sensitivity analyses between energy usage, cost savings, and payback on the investment of the operating parameters to understand the relationship between relevant variables. By utilizing parameters from a pulp and paper manufacturing facility, the research determines that the fuel cost, electricity cost, and steam flow rate are the most important parameters for the feasibility of the system with a desirable payback on the investment.

In this study, full-scale loading tests were conducted to investigate web-shear strengths of hollow-core slab (HCS) members strengthened in shear by using practically viable methods. All the HCS units used in the current test program were fabricated by using the individual mold method, not by the extrusion method, and the key experimental variables of the shear test were set as the presence of shear reinforcement, core-filling concrete, topping concrete, and also the magnitude of effective prestress. The shear force-displacement behaviors, crack patterns, and strain response of shear reinforcements were reported in detail. In addition, to identify the shear strength enhancement provided under various strengthening conditions in a quantitative manner, existing shear test results of series specimens, including a naked HCS member and corresponding composite HCS members with cast-in-place (CIP) concrete and/or shear reinforcements, were collected from literature. On this basis, a practical design expression capable of estimating shear strengths of HCSs strengthened with CIP concrete and stirrups was suggested based on the ACI 318 code equation. The proposed method evaluated the shear strengths of the collected specimens with a good level of accuracy, regardless of the presence of corefilling concrete, topping concrete, and shear reinforcements. Keywords: core-filling concrete; hollow-core slab (HCS); individual mold method; precast concrete; shear; topping concrete.