scholarly journals Muscle contributions to tibiofemoral shear forces and valgus and rotational joint moments during single leg drop landing

2020 ◽  
Vol 30 (9) ◽  
pp. 1664-1674 ◽  
Author(s):  
Nirav Maniar ◽  
Anthony G. Schache ◽  
Claudio Pizzolato ◽  
David A. Opar
Keyword(s):  
Shear Forces ◽  
Joint Moments ◽  
Drop Landing ◽  
Rotational Joint

The Effect of Ball Pad Metallurgy and Ball Composition on Solder Ball Integrity of Plastic Ball Grid Array Packages

1998 ◽  
Author(s):  
C.H. Zhong ◽  
Sung Yi
Keyword(s):  
Failure Mode ◽  
Barrier Layer ◽  
Shear Force ◽  
Solder Ball ◽  
Ball Grid Array ◽  
Reliability Test ◽  
Shear Forces ◽  
Ball Shear ◽  
Plastic Ball ◽  
Plastic Ball Grid Array

Abstract Ball shear forces of plastic ball grid array (PBGA) packages are found to decrease after reliability test. Packages with different ball pad metallurgy form different intermetallic compounds (IMC) thus ball shear forces and failure modes are different. The characteristic and dynamic process of IMC formed are decided by ball pad metallurgy which includes Ni barrier layer and Au layer thickness. Solder ball composition also affects IMC formation dynamic process. There is basically no difference in ball shear force and failure mode for packages with different under ball pad metallurgy before reliability test. However shear force decreased and failure mode changed after reliability test, especially when packages exposed to high temperature. Major difference in ball shear force and failure mode was found for ball pad metallurgy of Ni barrier layer including Ni-P, pure Ni and Ni-Co. Solder ball composition was found to affect the IMC formation rate.

New Systems for the Digestion of Solid Wastes

1992 ◽  
Vol 25 (7) ◽  
pp. 319-326 ◽  
Author(s):  
A. Wellinger ◽  
U. Baserga ◽  
K. Egger
Keyword(s):  
Dry Matter ◽  
Gas Production ◽  
Matter Content ◽  
Solid Wastes ◽  
Dry Matter Content ◽  
Feeding System ◽  
Shear Forces ◽  
Tank Reactor ◽  
Strong Shear ◽  
First Results

Two new systems for the digestion of solid wastes at thermophilic temperatures were developped and are currently being investigated at our research institute. The first system (ANCOM) was designed to process straw-rich cattle manure with a natural dry matter content of 18% to 22%. First results demonstrated a good specific gas production of 1.2 m3 biogas per m3 digester volume and day (54% methane) corresponding to a gas yield of 400 l per kg VS. A second digester system was developed to treat fruit, garden and vegetable (FGV-) waste. Because FGV-waste tends to float, a stirred tank reactor was designed in cooperation with an engineering firm. The reactor includes a distinguished new stirring system taking up strong shear forces and a hydraulic feeding system which guarantees that even during recirculation of the material, the hygenized digested substrate leaving the digester is not brought in contact with the fresh incoming material. First results measured at an HRT of 40 days demonstrated a specific gas production of 2.7 m3 per m3 fermenter and day.

scholarly journals Differences in strength and landing biomechanics between female jumpers and swimmers

2021 ◽  
pp. 1-11
Author(s):  
Mianfang Ruan ◽  
Qiang Zhang ◽  
Xin Zhang ◽  
Jing Hu ◽  
Xie Wu
Keyword(s):  
Muscle Force ◽  
Female Athletes ◽  
Young Female ◽  
Single Component ◽  
Plyometric Training ◽  
Isokinetic Testing ◽  
Female College ◽  
Landing Biomechanics ◽  
Drop Landing ◽  
Landing Mechanics

BACKGROUND: It remains unclear if plyometric training as a single component could improve landing mechanics that are potentially associated with lower risk of ACL injury in the long term OBJECTIVE: The purpose of this study was to investigate the influence of experience undertaking plyometrics on landing biomechanics in female athletes. METHODS: Non-jumpers with little experience in plyometric training (12 female college swimmers) and jumpers with five years of experience in plyometric training (12 female college long jumpers and high jumpers) were recruited to participate in two testing sessions: an isokinetic muscle force test for the dominant leg at 120∘/s and a 40-cm drop landing test. An independent t test was applied to detect any significant effects between cohorts for selected muscle force, kinematic, kinetic, and electromyography variables. RESULTS: While female jumpers exhibited greater quadriceps eccentric strength (P= 0.013) and hamstring concentric strength (P= 0.023) during isokinetic testing than female swimmers, no significant differences were observed in kinematics, kinetics, and muscle activities during both drop landing and drop jumping. CONCLUSIONS: The results suggest that the female jumpers did not present any training-induced modification in landing mechanics regarding reducing injury risks compared with the swimmers. The current study revealed that plyometric training as a single component may not guarantee the development of low-risk landing mechanics for young female athletes.

scholarly journals The Design and Simulation of a 16-Sensors Plantar Pressure Insole Layout for Different Applications: From Sports to Clinics, a Pilot Study

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1450
Author(s):  
Alfredo Ciniglio ◽  
Annamaria Guiotto ◽  
Fabiola Spolaor ◽  
Zimi Sawacha
Keyword(s):  
Pressure Distribution ◽  
Plantar Pressure ◽  
Center Of Pressure ◽  
Reaction Force ◽  
Weight Lifting ◽  
Lower Limbs ◽  
Plantar Pressure Distribution ◽  
Drop Landing ◽  
Mean Pressure ◽  
Footwear Design

The quantification of plantar pressure distribution is widely done in the diagnosis of lower limbs deformities, gait analysis, footwear design, and sport applications. To date, a number of pressure insole layouts have been proposed, with different configurations according to their applications. The goal of this study is to assess the validity of a 16-sensors (1.5 × 1.5 cm) pressure insole to detect plantar pressure distribution during different tasks in the clinic and sport domains. The data of 39 healthy adults, acquired with a Pedar-X® system (Novel GmbH, Munich, Germany) during walking, weight lifting, and drop landing, were used to simulate the insole. The sensors were distributed by considering the location of the peak pressure on all trials: 4 on the hindfoot, 3 on the midfoot, and 9 on the forefoot. The following variables were computed with both systems and compared by estimating the Root Mean Square Error (RMSE): Peak/Mean Pressure, Ground Reaction Force (GRF), Center of Pressure (COP), the distance between COP and the origin, the Contact Area. The lowest (0.61%) and highest (82.4%) RMSE values were detected during gait on the medial-lateral COP and the GRF, respectively. This approach could be used for testing different layouts on various applications prior to production.

Shear Forces between Tethered Polymer Chains as a Function of Compression, Sliding Velocity, and Solvent Quality

2003 ◽  
Vol 36 (2) ◽  
pp. 389-398 ◽  
Author(s):  
Phillip A. Schorr ◽  
Thomas C. B. Kwan ◽  
S. Michael Kilbey ◽  
Eric S. G. Shaqfeh ◽  
Matthew Tirrell
Keyword(s):  
Polymer Chains ◽  
Sliding Velocity ◽  
Shear Forces ◽  
Solvent Quality ◽  
Tethered Polymer Chains

Large Deflection of a Rectangular Plate Resting on a Pasternak-Type Elastic Foundation

1977 ◽  
Vol 44 (3) ◽  
pp. 509-511 ◽  
Author(s):  
P. K. Ghosh
Keyword(s):  
Rectangular Plate ◽  
Elastic Foundation ◽  
Large Deflection ◽  
Lateral Load ◽  
Bending Moments ◽  
Shear Forces ◽  
Simply Supported ◽  
Base Parameters ◽  
Square Plate

The problem of large deflection of a rectangular plate resting on a Pasternak-type foundation and subjected to a uniform lateral load has been investigated by utilizing the linearized equation of plates due to H. M. Berger. The solutions derived and based on the effect of the two base parameters have been carried to practical conclusions by presenting graphs for bending moments and shear forces for a square plate with all edges simply supported.

Sign in / Sign up

Export Citation Format

Share Document