[Purpose] To quantify the ratio of activation of the infraspinatus and posterior deltoid muscles and the anterior gliding motion of the humeral head during external rotation (ER) motions of the shoulder performed in prone position against different external resistance loads. [Subjects] Twenty healthy women between the ages of 20 and 30 years. [Methods] Activity ratio was quantified as the diffe...

Because of the need to evaluate anthropomorphic test device (ATD) biofidelity under high-head angular accelerations, the purpose of the present investigation was to develop appropriate instrumentation for intact post mortem human subject (PMHS) testing, validate the instrumentation, and obtain information to characterize the response of the head-neck complex under this loading scenario. A serie...

Model parameters of conditioned soils in head chamber of shield machine are determined based on tri-axial compression tests in laboratory. The loads acting on tunneling face are estimated according to static earth pressure principle. Based on Duncan-Chang nonlinear elastic constitutive model, the earth pressures on head chamber of shield machine are simulated. The variation of earth pressure on...

The reason of this study is low cycle failure of cast iron cylinder head during the E5 standard durability test. The goal of the present investigation is durability test simulation and low cycle fatigue life evaluation of cast iron cylinder head. With uncouple structural analysis, preloads, thermal and mechanical load and boundary conditions are prescribed to finite element model of the cylinde...

Thirty-degree pitch-down helicopter crash pulses were examined at the Patuxent River Horizontal Accelerator facility. The pulses used were representative of standard seat qualification crash corridors for a variety of rotary wing platforms. The primary objectives of this effort were 1) to quantitatively determine the effect of varying helmet weight and center of gravity (CG) during simulated ro...

OBJECTIVE To describe the determinants of the severity of the head kinematics of a pedestrian when struck by common sport utility vehicles (SUV) and work utility vehicles (WUVs) to assess how effective assessment protocols are in assessing injury risk for SUVs and work utilities. METHODS Three hundred twenty-four simulations of pedestrian collisions with SUVs, work utility vehicles, and sedan...

There are many papers on head modeling in literature [1]. Generally, the topic of most of them is designing and modeling devices for head (especially brain) protection, e.g. helmets. On the other side, most papers are about modeling of whole part of top body (a torso and a head). The main aim of these researches is simulation of the backbone behavior under external load applied to the head. The...

Since prestressed concrete members rely on the tensile strength of the prestressing strands to resist loads, loss of even few them could result catastrophic. Therefore, it is important to measure present residual prestress force. Although there are some techniques for obtaining present prestress force, some problems still remain. One method is to install load cell in front of anchor head but th...

New generation pilot helmets with mounted devices enhance the capabilities of pilots substantially. However, the additional equipment increases the helmet weight and shifts its center of mass forward. Two helmets with different mass properties were modeled to simulate their effects on the pilot's neck. A musculoskeletal computer model was used, with the methods of inverse dynamics and static op...

The purpose of this study was to compare the subjective perceptual responses to both head-loading and back-loading in a group of Xhosa women. Thirty two women were divided into three groups based on their experience of head-loading and walked on a treadmill on two occasions, head-loading and back-loading, at a self selected walking speed for 4 min with a variety of loads until pain or discomfor...