neck thickness
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2022 ◽  
Vol 11 (6) ◽  
pp. 676-684
Author(s):  
Mata Prasad ◽  
Sutanu Maji

Off-season onion production of is an important issue to challenge the price fluctuation during different time of year and in different location of the country. The present experiment was conducted at sub-tropical region of central Uttar Pradesh (Lucknow) during kharif, late kharif season of 2018-20 to find out the optimum date of transplanting and choice of suitable cultivar of onion for off-season production. The experiment consisted of eight dates of transplanting (30th August, 10, 20, 30th September, 10, 20, 30th October and 10th November) and two cultivars (Agrifound Dark Red and L-883) which was laid out in factorial randomized block design with three replications. Transplanting on 30th September showed maximum vegetative growth in terms of plant height (66.93 cm), number of leaves per plant (14.99), maxi-mum length of leaf (47.60 cm), neck thickness (23.19 mm) at 120 days after transplanting as well as highest average bulb weight (79.53 g) and bulb yield ( 10.02kg/plot and 382.68 q/ha). Among the two varieties L-883 showed the better performance in respect of growth and yield in off season production. Therefore, it may be concluded that the cultivation of L-883 variety and transplanting on 30th September was found best for off –season production in the sub –tropical agro- climatic region of Center Uttar Pradesh (Lucknow) which may be beneficial for increasing farmers’ income as well as for benefit of costumers keeping the balance between demand and supply.


Author(s):  
Sandra Friedrich ◽  
Thoralf Gerstmann ◽  
Carolin Binotsch ◽  
Birgit Awiszus

AbstractThe striving for energy savings by lightweight construction requires the combination of different materials with advantageous properties. For joining sheet metal components, clinching offers a good alternative to thermal joining processes. In contrast to thermal joining processes, the microstructure in the joining zone remains largely unaffected. Conventional clinch joints, however, have a protrusion on the underside of the joint, which restricts their use in functional and visible surfaces. Flat-clinching minimizes this disadvantage by using a flat anvil instead of a die. Due to the flatness on the underside, it can be used in visible and functional surfaces. This paper deals with the increase of joint strength by using an auxiliary joining element (AJE) in the second forming stage. To achieve optimum improvement in the joint strength of an aluminum Al99.5 H14 sheet metal joint and to save costs, the AJE was varied numerically in terms of volume, material and basic shape. The geometric parameters (e.g., interlocking f and neck thickness tn) do not allow direct derivation of the joint strength. For this reason, the 2D clinch model was extended for the first time to include 3D load models (cross tension, shear tension). To validate the numerical results, optimized flat-clinch joints with AJE and the associated load tests were implemented experimentally. The numerical models were used to improve the process development.


2021 ◽  
Author(s):  
Menghan Wang ◽  
Yifeng Chen ◽  
Yan Han ◽  
Lei Li ◽  
Menglong Du

Abstract Aiming at the problems of low strength and unsatisfactory connection quality of plastic clinching of heterogeneous lightweight materials for the cars body, the Q235 steel sheets, and 5052 aluminum alloy sheets were taken as the research objects, and the inclined wall die for plastic clinching was designed based on the deformation and flow characteristics of sheets in the plastic clinching process. The elastic-plastic finite element numerical simulation and experimental research were used to analyze the plastic clinching process of the inclined wall die, and the failure mode and mechanism of the clinching joints in the shear and peel experiment were deeply studied. The results show that the inclined wall die can effectively increase the interlock value of the joints and reduce the maximum joining force during the clinching process under the condition of ensuring the neck thickness of the joints. When the inclined wall angle α increases from 90° to 100°, the interlock value increases by 38.9%, and the maximum joining force decreases by 8.3%. The influence of inclined wall structure on joint quality can be divided into extrusion stage, radial inflow stage, and stability stage. The comparison between the clinching experiment and the finite element results shows that the two results are in good agreement, which proves that the finite element model of plastic clinching of inclined wall die has a high degree of credibility, and verifies the feasibility of practical application of inclined wall die. Finally, under shear and peel loads, the main failure mode of the joints is separation failure.


2021 ◽  
Vol 16 (AAEBSSD) ◽  
pp. 34-37
Author(s):  
S. K. Tyagi ◽  
G. S. Kulmi ◽  
A. R. Khire

An experiment was conducted in the Rabi season of two consecutive years of 2019-20 and 2020-21, respectively to determine find out practically convenient and economic weed control measure for the onion growers. Treatments comprised T1 Farmers’ practice (pendimethalin 30% EC 1 kg ai/ha before transplanting+ 1HW at 25 DAT) and T2 (oxyflurofen 23.5% EC @ 0.10 kg ai/ha + quizalofop ethyl 5% EC @ 0.05 kg ai/ha at 25 DAT + 1 HW at 45 DAT) replicated at ten farmers’ field. Treatment T2 (oxyflurofen 23.5% EC @ 0.10 kg ai/ha + quizalofop ethyl 5% EC @ 0.05 kg ai/ha at 25 DAT + 1 HW at 45 DAT) recorded significantly lowest weed density (32.59/m2), highest plant height (52.50 cm), neck thickness (1.12 cm),bulb diameter (6.38 cm), bulb weight (92.57 g) and bulb yield (304.85 q/ha) as compared to treatment T1. The highest net returns (Rs 2,04,391/ha) and B:C (3.04) were obtained with T2.


Author(s):  
M. Mustafa Haris ◽  
Khuwaja Safiullah Osmani ◽  
M. Mobin Younusi

A Field experiment was conducted to study the effect of different levels of sulphur on growth and yield of onion under drip irrigation on years (2013-2014) at RHREC, College of Horticulture, Bangalore. The experiment was conducted with a Randomized block design with four replications. The treatments comprised of 7 combinations (0, 15, 30, 45, 60, 75 and 90 kg S/ha) in which sulphur was supplied through gypsum. The results indicated significantly higher bulb yield (61.96t ha-1) and yield components like average bulb weight, bulb yield per plot and marketable bulb yield was obtained due to application of recommended dosage of fertilizer plus 45 kg S ha-1. The growth components viz., plant height, number of leaves, collar thickness and neck thickness showed significant with the application of result in the recommended dosage of fertilizer plus 45 kg S ha-1. Compared to other levels of sulphur.


2021 ◽  
Author(s):  
Xin Jin ◽  
Ruilin Gao ◽  
Chaojiang Li ◽  
Zhongpeng Zheng ◽  
Muzheng Xiao ◽  
...  

Abstract As flexible joint is a typical low-rigidity micro part, which have four narrow neck structures evenly distributed around its central axis, it is necessary to strictly control the dimensional accuracy of the narrow necks to improve the consistency of stiffness. However, the radius of the arc of the narrow necks is less than 2mm , and the thickness of thinnest part of the necks formed by two adjacent arcs is only tens of microns, which also has sub-micron accuracy requirement. These cross-scale dimensional characteristics and accuracy requirements give rise to extremely difficulty on the measuring process. In this paper, an on-machine measurement method for the semicircular narrow necks was presented and a measuring device was developed based on the comparative principle by making full use of the high linearity characteristic in the small measuring range of the sensor probes. Meanwhile, the on-machine measurement process based on ultra-precision machine tools was also introduced in details. The experiments results show that the measurement error of the method proposed is less than 0.2 µm , and the repeatability is less than 0.1 μm , which meet the measuring requirement of flexible joint. Furthermore, the theoretical error and the uncertainty caused by probe position, measurement force, environmental factor and the accuracy of the sensor was analyzed, which could provide further evidences to improve the measuring accuracy of micro-scale hybrid surface texture.


Author(s):  
Chao Chen ◽  
Huiyang Zhang ◽  
Hao Peng ◽  
Xiangkun Ran

In order to reduce the protrusion height and increase the strength of the clinched joint, a two-step clinching method was investigated in the present study. The whole process contains two steps. The first step is used to produce one-step clinched joints, and the second step is used to press the one-step clinched joints to reduce the protrusion height and increase the joining strength. The influences of clinching steps and sheet thicknesses on the mechanical properties of the clinched joint were investigated. The main failure mode of all the clinched joints in the strength tests is the neck fracture mode. The neck thickness can be enlarged by the two-step clinching method, and the protrusion height can be reduced. TCJ2.5-2.0 joint has the highest energy absorption and strength, and OCJ2.0-2.5 joint has the lowest energy absorption and strength. The two-step clinching process can contribute to increasing energy absorption and joining strength. For getting higher strength, the thick sheet should be taken as the top sheet. With higher strength and lower protrusion, the use of two-step clinched joint will be convenient in the mechanical engineering areas.


Author(s):  
S. Aruna ◽  
P. Indira ◽  
Jalaja S. Menon

Background: Onion (Allium cepa L.) is an important and indispensable item of every kitchen. It is used as a vegetable, spice and condiment and commands an extensive internal market. Even though onion is one of the major crops in India, its cultivation is not yet popular in Kerala. Successful onion production depends on the selection of varieties that are adapted to different conditions imposed by specific environment and best planting time. In this background, the current study aimed to evaluate five onion varieties in the tropical planes of Kerala and also to study the effect of different planting time and varieties on the performance of onion in Kerala.Methods: Five onion varieties were evaluated in four different dates of planting with an interval of fifteen days. Planting commenced from 10th November to 25th December 2017 in a split plot design with four replications. Yield attributing characters such as number of leaves per plant, leaf length, bolting percentage, neck thickness, bulb weight and yield were noted. Result: All the parameters showed a significant variation over different dates of planting. There was a significant variation in number of leaves per plant, leaf length, bolting percentage, total bulb yield and neck thickness among the varieties. Interaction effect of varieties and dates of planting was significant only for leaf length and total bulb yield. Highest bulb weight was recorded in 25th Nov. planting. Highest yield was recorded in 25th Nov. which was on par with 10th Dec. and 10th Nov. plantings. Arka Kalyan recorded a highest yield, which was statistically on par with Agrifound Dark Red and Arka Pragati. Varieties when planted on 25th Dec. recorded a lowest neck thickness. Agrifound White exhibited a non-bolting behavior in all the dates of planting. Overall performance and yield of onion was found to be better when planting was done on 25th November.


Author(s):  
Chiara Gastaldi ◽  
Muzio M. Gola

Abstract The purpose of this paper is to develop an attractive tool for designers in the initial design phase of the damping of turbomachinery blades through dry friction underplatform dampers. The paper shows how, to this purpose, certain reasonable simplifications are introduced in the procedure and in the model, leaving the customary full high fidelity computations to the final design verification analysis. The key simplifications here considered are: the blade neck is modelled with Euler beam finite elements (FE) to speed up the updating of its dimensions during the optimisation process; the contact forces exerted by the dampers on the blade platform are represented by the resultant forces and moments applied to a reference point on the platform, associated to its displacements and rotations; the airfoil, which, due to its complex shape, is considered fixed during the coupled optimization of the damper, is obtained from a full 3D FE model after a component mode synthesis reduction. It is shown that the process captures the essentials of the nonlinear dynamics of the blade-damper problem without sacrificing in any way the accuracy of the results. This hybrid model is then employed in the process where the domains of optimal matching between the damper and the blade is searched for by exploring the influence of blade neck thickness (flexibility) and damper mass. Such a purposely simplified process allows a clear identification of relationships between relevant blade features and response with a focus on fatigue life.


Author(s):  
P. M. Parés- Casanova ◽  
A. Kabir

Sexual dimorphism, defined as phenotypic differences between males and females, is a common phenomenon in animals. In this line, Rensch’s rule states that sexual size dimorphism increases with increasing body size when the male is the larger sex and decreases with increasing average body size when the female is the larger sex. Domesticated animals offer excellent opportunities for testing predictions of functional explanations of Rensch’s theory. Pigeon breeds encounters many different functional purposes and selective constraints, which could influence strongly their morphology. The aim of this paper is to examine, for first time, Rensch’s rule among domestic pigeons. It was compiled a database of 12 quantitative traits (body weight, body height, beak thickness, beak length, neck length, neck thickness, wing length, rump width, tail length, tarsus length, tarsus thickness and middle toe length) for males and females of 11 different domestic pigeon breeds: Bangladesh Indigenous, Racing Homer, Turkish Tumbler, Indian Lotan, Kokah, Mookee, Indian Fantail, Bokhara Trumpeter, Bombai, Lahore and Hungarian Giant House; Rock Pigeon (Columba livia) was also considered as wild relative for comparative purposes. Comparative results between males and females showed that only body weight, wing length and neck thickness were consistent with Rensch’s rule. The rest of trait did not present correlations. Among domestic pigeons, there can appear different expressions of dimorphism according to each trait, so it must be considered that Rensch’s rule vary when considering other traits than body weight.


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