Variation and Correlation of Shearing Force with Feed Nutritional Characteristics of Wheat Straw

Cui, X.M.,Yang, Z.B.,Yang, W.R.,Jiang, S.Z.,Zhang, G.G.,Liu, L.,Wu, B.R.,Wang, Z.F. Asian Australasian Association of Animal Productio 2013 Animal Bioscience Vol.26 No.10

This experiment was conducted to study the variation laws and correlations of shearing force and feed characteristics including morphological characteristic, chemical composition and in situ degradability of wheat straw. Feasibility of evaluating the nutritional value of wheat straws with shearing force values was analyzed in this study. Six hundred wheat straw plants (Jimai 22) were randomly selected and placed in a cool and ventilated place. Samples were collected in the 1st, 15th, 30th, 45th, 60th d after harvest to measure shearing force, morphological characteristic, nutritional composition. Rumen degradation of dry matter (DM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) of wheat straws were determined by the nylon bags method. The results demonstrated that linear and quadratic effects of storage time on all the tested morphological characteristics were significantly correlative (p<0.01). As storage time goes on, all the tested nutrients and their rumen degradations of wheat straw was linearly (p<0.01) and quadratic (p<0.01) correlative except ADF content and rumen degradation of ADF. Significant correlations were determined in linear effect of shearing force on morphological characteristics (p<0.01), and linear density and diameter were a more sensitive predictor than stem thickness for shearing force. There were strong correlations between storage time and all the measured physical characteristics (shearing force, morphological characteristics and shearing force standardized by morphological characteristics) (p<0.01). Nutrition compositions were linearly correlative with shearing force and standardized shearing force (p<0.01). The linear correlation between rumen degradation of DM and NDF and shearing force and standardized shearing force were evident (p<0.01). In conclusion, shearing force, nutrition compositions and their rumen degradation of wheat straw were still dynamic with storage time after harvest. Correlation could be found between shearing force and nutritional characteristics of wheat straw. Nutrient content, morphological index and rumen degradation of DM and NDF could be predicted by changes in shearing force. Shearing force should be applied according to a standardized storage time when it is used to forecast the feed value of wheat straws.

Correlations among Shearing Force, Morphological Characteristic, Chemical Composition, and In situ Digestibility of Alfalfa (Medicago sativa L) Stem

Liu, L.,Yang, Z.B.,Yang, W.R.,Jiang, S.Z.,Zhang, G.G. Asian Australasian Association of Animal Productio 2009 Animal Bioscience Vol.22 No.4

Alfalfa (Medicago sativa L) is a high-quality forage for ruminants and the main stem is the dominant morphological component contributing to the forage nutritive value in mature alfalfa forage. Shearing force, a fracturing property of plant stem, is an important indictor of forage value. The objectives of this study were to investigate the effects of morphological characteristic on shearing force, the relationship between shearing force and chemical composition, and the relationship between shearing force and in situ digestibility of alfalfa stem. The results showed that linear density (weight per unit length of stem) was more important than chemical composition in affecting shearing force. There was a positive relationship between lignin content and shearing force (r = 0.78). Correlations were not found between shearing force and other chemical components such as neutral detergent fiber (NDF), acid detergent fiber (ADF), cellulose and hemicelluloses. In situ digestibility (of dry matter and NDF) was related to shearing force. A negative correlation was found between shearing force and dry matter (DM) digestibility (r = -0.70), and there was also a negative correlation between shearing force and NDF digestibility (r = -0.87). When shearing force was standardized for stem diameter or stem linear density, the relationship between shearing force and digestibility was consistent regardless of stem diameter and stem linear density. Shearing force was significantly correlated with lignin content and in situ digestibility (of DM and NDF), and was a more direct indicator for estimating forage nutritive value related to animal performance, so it can be used to predict the forage value of alfalfa.

인청동의 전단가공에서 예비 전단가공이 슬리버 발생에 미치는 영향 연구

신미경,김병섭,이춘규 한국기계기술학회 2022 한국기계기술학회지 Vol.24 No.5

Burr occurs at the bottom of the material as the material breaks during shearing, and sliver occurs in shear droop that occurs when a punch penetrates the surface of the material. Sliver refers to the shape of a long and thin thread, and it is an important defect that can cause a short when assembled into electronic parts other than a defect in the appearance of a product, an assembly defect in the post-process, and an injury to the operator. Sliver does not occur when the molding is completed only by the main shearing without pre-shearing, but sliver occurs when the main shearing is performed after the pre-shearing. The purpose of this study is to study the sliver generation mechanism that occurs during main shearing after pre-shearing. Using the material phosphor bronze C5210-EH(HP), the sliver was observed with the dimensions and stripping force of the pre-shearing as variables, and the effect of the pre-shearing on the sliver was studied. The product used in the experiment is a terminal, a press product that is assembled on a 0.4mm pitch FPC connector. Three experimental variables were selected: the X-axis allowance, the Y-axis length, and the stripping force in the dimensions of the pre-shearing. As a result of 12 experimental conditions, the X-axis allowance had a greater effect on sliver generation than the Y-axis length and stripping force. The cause of sliver during pre-shearing is that the shear droop part is elongated due to bending when the punch is lowered due to the hole in the bottom due to pre-shearing.

Shear strength analyses of internal diaphragm connections to CFT columns

Liping Kang,Roberto T. Leon,Xilin Lu 국제구조공학회 2015 Steel and Composite Structures, An International J Vol.18 No.5

Previous theoretical equations for the shear capacity of steel beam to concrete filled steel tube (CFT) column connections vary in the assumptions for the shear deformation mechanisms and adopt different equations for calculating shear strength of each component (steel tube webs, steel tube flanges, diaphragms, and concrete etc.); thus result in different equations for calculating shear strength of the joint. Besides, shear force-deformation relations of the joint, needed for estimating building drift, are not well developed at the present. This paper compares previously proposed equations for joint shear capacity, discusses the shear deformation mechanism of the joint, and suggests recommendations for obtaining more accurate predictions. Finite element analyses of internal diaphragm connections to CFT columns were carried out in ABAQUS. ABAQUS results and theoretical estimations of the shear capacities were then used to calibrate rotational springs in joint elements in OpenSEES simulating the shear deformation behavior of the joint. The ABAQUS and OpenSEES results were validated with experimental results available. Results show that: (1) shear deformation of the steel tube dominates the deformation of the joint; while the thickness of the diaphragms has a negligible effect; (2) in OpenSEES simulation, the joint behavior is highly dependent on the yielding strength given to the rotational spring; and (3) axial force ratio has a significant effect on the joint deformation of the specimen analyzed. Finally, modified joint shear force-deformation relations are proposed based on previous theory.

수정 진동자 원자 힘 현미경의 대기 중 탐침 쉬어 상호작용

최효주,김동원,이만희,최명철 한국물리학회 2021 새물리 Vol.71 No.5

We investigate the tip-substrate interaction in shear-mode, quartz-tuning, fork-based atomic force microscopy in air. While the tip-substrate normal interaction in vacuum is usually characterized as a long-range attractive force and a short-range repulsive force, here, in shear-mode atomic force microscopy in air, we observe a negligible shear interaction until the tip abruptly experiences a viscoelastic force at a few nanometers above the sample’s surface. We show that the viscoelastic shear interaction is the result of a capillary-condensed water bridge formed in the nanosized gap between the tip and the substrate and that the shear interaction increases with decreasing tip-substrate separation until hard mechanical contact is made between the tip and the substrate. This shear interaction mediated by the capillary liquid bridge dominates over other interactions; thus, the shear force must be considered when performing shear-mode atomic force microscopy and spectroscopy and manipulation of nano-objects in air. 우리는 수정 진동자 기반 대기 중 쉬어 모드 원자 힘 현미경에서 나노 탐침에 작용하는 쉬어 상호작용측정하였다. 진공 중 원자 힘 현미경의 수직 방향 상호작용에서 나타나는 원거리 인력과 근거리 반발력의특징과 다르게, 대기 중 쉬어 상호작용에서는 팁-표면 원거리 상호작용이 거의 없고, 팁-표면 수 나노거리 지점부터 갑작스러운 힘이 발생함을 관측하였다. 여기서 팁-표면 수 나노 지점에서 발생하는쉬어 상호작용은 팁-표면 사이 캐필러리 응축에 의한 나노 액체 브릿지 생성의 결과이며, 표면에 더욱 다가갈수록 팁-표면 기계적 접촉에 의한 큰 쉬어 탄성 힘과 댐핑 힘이 작용함을 보인다. 이러한 상호작용은대기중 쉬어 모드 수정 진동자 원자 힘 현미경의 구동, 원자 힘 현미경을 이용한 나노 물체 조작 등 다양한응용연구에서 고려할 중요한 요소이다.

Genome-wide Association Study for Warner-Bratzler Shear Force and Sensory Traits in Hanwoo (Korean Cattle)

Dang, C.G.,Cho, S.H.,Sharma, A.,Kim, H.C.,Jeon, G.J.,Yeon, S.H.,Hong, S.K.,Park, B.Y.,Kang, H.S.,Lee, S.H. Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.9

Significant SNPs associated with Warner-Bratzler (WB) shear force and sensory traits were confirmed for Hanwoo beef (Korean cattle). A Bonferroni-corrected genome-wide significant association (p< $1.3{\times}10^{-6}$) was detected with only one single nucleotide polymorphism (SNP) on chromosome 5 for WB shear force. A slightly higher number of SNPs was significantly (p<0.001) associated with WB shear force than with other sensory traits. Further, 50, 25, 29, and 34 SNPs were significantly associated with WB shear force, tenderness, juiciness, and flavor likeness, respectively. The SNPs between p = 0.001 and p = 0.0001 thresholds explained 3% to 9% of the phenotypic variance, while the most significant SNPs accounted for 7% to 12% of the phenotypic variance. In conclusion, because WB shear force and sensory evaluation were moderately affected by a few loci and minimally affected by other loci, further studies are required by using a large sample size and high marker density.

Shear transfer mechanism in connections involving concrete filled steel columns under shear forces

Silvana De Nardin 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.28 No.4

This paper reports the experimental results of three through bolt beam-column connections under pure shear forces using modified push-out tests. The investigated specimens include extended end-plates and six through-bolts connecting square concrete-filled steel tubular column (S-CFST) to steel beams. The main goal of this study is to investigate if and how the mechanical shear connectors, such as steel angles and stud bolts, contribute to the shear transfer mechanisms in the steel-concrete interface of the composite column. The contribution of shear studs and steel angles to improve the shear resistance of steel-concrete interface in through-bolt connections was investigated using tests. The results showed that their contribution is not significant when the beam-column connection is included in the push-out tests. The specimens failed by pure shear of the long bolts, and the ultimate load can be predicted using the shear resistance of the bolts under shear forces. The predicted values of load allowed obtaining a good agreement with the tests results.

Numerical studies on non-shear and shear flows past a 5:1 rectangular cylinder

Qiang Zhou,Shuyang Cao,Zhiyong Zhou 한국풍공학회 2013 한국풍공학회지 Vol.17 No.4

Large Eddy Simulations (LES) were carried out to investigate the aerodynamic characteristics of a rectangular cylinder with side ratio B/D=5 at Reynolds number Re=22,000 (based on cylinder thickness). Particular attention was devoted to the effects of velocity shear in the oncoming flow. Time-averaged and unsteady flow patterns around the cylinder were studied to enhance understanding of the effects of velocity shear. The simulation results showed that the Strouhal number has no significant variation with oncoming velocity shear, while the peak fluctuation frequency of the drag coefficient becomes identical to that of the lift coefficient with increase in velocity shear. The intermittently-reattached flow that features the aerodynamics of the 5:1 rectangular cylinder in non-shear flow becomes more stably reattached on the high-velocity side, and more stably separated on the low-velocity side. Both the mean and fluctuating drag coefficients increase slightly with increase in velocity shear. The mean and fluctuating lift and moment coefficients increase almost linearly with velocity shear. Lift force acts from the high-velocity side to the low-velocity side, which is similar to that of a circular cylinder but opposite to that of a square cylinder under the same oncoming shear flow.

Numerical studies on non-shear and shear flows past a 5:1 rectangular cylinder

Zhou, Qiang,Cao, Shuyang,Zhou, Zhiyong Techno-Press 2013 Wind and Structures, An International Journal (WAS Vol.17 No.4

Large Eddy Simulations (LES) were carried out to investigate the aerodynamic characteristics of a rectangular cylinder with side ratio B/D=5 at Reynolds number Re=22,000 (based on cylinder thickness). Particular attention was devoted to the effects of velocity shear in the oncoming flow. Time-averaged and unsteady flow patterns around the cylinder were studied to enhance understanding of the effects of velocity shear. The simulation results showed that the Strouhal number has no significant variation with oncoming velocity shear, while the peak fluctuation frequency of the drag coefficient becomes identical to that of the lift coefficient with increase in velocity shear. The intermittently-reattached flow that features the aerodynamics of the 5:1 rectangular cylinder in non-shear flow becomes more stably reattached on the high-velocity side, and more stably separated on the low-velocity side. Both the mean and fluctuating drag coefficients increase slightly with increase in velocity shear. The mean and fluctuating lift and moment coefficients increase almost linearly with velocity shear. Lift force acts from the high-velocity side to the low-velocity side, which is similar to that of a circular cylinder but opposite to that of a square cylinder under the same oncoming shear flow.

Ultrastructural Changes and Shear Force of Duck Meat during Aging at 0˚C

Young Boong Kim,Ki Hong Jeon,Young Ho Kim,Nam Hyuck Lee,Su Kyung Ku,Aera Jang 한국축산식품학회 2012 한국축산식품학회지 Vol.32 No.5

The purpose of this study was to evaluate the ultrastructural and shear force changes of duck breast and leg meat during aging at 0˚C. Pekin ducks (45 d old) purchased from Greemud Co. were used for this experiment, and were stored at 0˚C for 7 d in order to determine the changes of the meat structure using transmission electron microscopy (TEM) and shear force. At day 0, A-band, I-band, M-line and Z-line of sarcomeres were seen clearly, but sarcomeres started to lose structure and become extended in length from day 2. With extended aging periods, myofibrils were destroyed and symptoms of aging became more obvious. In the duck breast meat, some myofibrils were also destroyed at the Z-line, but were mainly destroyed at the M-line. The change in structure of duck leg meat over time was similar to that of breast meat. After five days and seven days of aging, mitochondria size and quantity were determined to be increased between the myofibrils. Shear force was decreased over time. From this study, aging at 0˚C was found to negatively influence the ultrastructure and shear force of duck meat.