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Aggregate Interlock in critical shear cracks Numerous models have been published for estimating the shear capacity of reinforced and prestressed concrete members without transverse reinforcement. Some approaches assume that the shear force is essentially carried by crack friction. Others consider the uncracked concrete compression zone as the governing load‐bearing mechanism. To address this question, 10 tests were conducted on reinforced concrete beams without stirrups. The focus of the tests was to record crack development and to measure crack opening and crack sliding. Using conventional and modern measurement methods, such as digital image correlation (DIC), the load‐bearing behavior was extensively recorded and evaluated. Furthermore, the crack surfaces were inspected and the shear friction was calculated. According to the conducted investigations, crack friction carries only a small proportion of the total shear force. The results of the research project thus contribute to a better understanding of shear force transfer in reinforced concrete members without shear reinforcement. [ABSTRACT FROM AUTHOR]

The article talks about the influence of the shore hardness on the kinematic movement behavior as well as examined for the breakdown characteristics of the suction pad. It mentions that the production of the capacitive sensor pattern is done with the hot press process as well as its cohesive integration as a material composite in the suction pad structure explained.

Introduction: This article analyses adult stroke clients' experiences with the Hemi Kinematics Bio Control (H.K.B.C) therapy method which is a specific form of EMG biofeedback. Clients' perspectives are of fundamental importance for the development, evaluation and client-oriented selection of innovative interventions. Methods: In cooperation with an ambulatory occupational therapy practice, a qualitative interview study with nine stroke clients was conducted, including analysis and evaluation. Inclusion and exclusion criteria ensured sufficient treatment experience by expert therapists as well as adequate cognitive and linguistic skills. Results: Key elements of H.K.B.C mentioned by the clients are external, visual feedback, understanding of neurophysiological correlations and the development of awareness of one's own body. The possibility to participate actively and equally in the treatment is experienced as a particular important feature of the method. At the same time the interviews provide insights into challenging and problematic aspects. Conclusion: The participating clients experience H.K.B.C as a valuable addition to regular therapy and as extremely helpful for both, clients and therapists. It is important to note that the participants are characterized by a comparatively high level of activity and cognitive skills. [ABSTRACT FROM AUTHOR]

Comparative studies of fish swimming have been limited by the lack of quantitative definitions of fish gaits. Traditionally, steady swimming gaits have been defined categorically by the fin or region of the body that is used as the main propulsor and named after major fish clades (e.g. carangiform, anguilliform, balistiform, labriform). This method of categorization is limited by the lack of explicit measurements, the inability to incorporate contributions of multiple propulsors and the inability to compare gaits across different categories. I propose an alternative framework for the definition and comparison of fish gaits based on the propulsive contribution of each structure (body and/or fin) being used as a propulsor relative to locomotor output, and demonstrate the effectiveness of this framework by comparing three species of neotropical cichlids with different body shapes. This approach is modular with respect to the number of propulsors considered, flexible with respect to the definition of the propulsive inputs and the locomotor output of interest, and designed explicitly to handle combinations of propulsors. Using this approach, gait can be defined as a trajectory through propulsive space, and gait transitions can be defined as discontinuities in the gait trajectory. By measuring and defining gait in this way, patterns of clustering corresponding to existing categorical definitions of gait may emerge, and gaits can be rigorously compared across categories. [ABSTRACT FROM AUTHOR]

A cross-sectional study with five different experienced show jumping and eventing horses was undertaken to prepare a simple and versatile possibility to objectify jumping movement in training and competition in order to optimize training and health maintenance. From the state of scientific research, continuing theoretical considerations and previously performed measurements with the selected inertial sensors, a large pool of possible performance-relevant parameters is selected. Its presentability should be proofed in the next step in field trials by an inertial measurement unit embedded in a saddle belt. The horses were ridden over a single vertical fence with a height of 1.30m. For the purpose of a standardized jumping movement, a gymnastic series is prefixed in half of the trials (n=30). The other half is approached in normal canter. A three dimensional accelerometer and a gyroscope, embedded in the saddle belt, illustrate the kinematics of the horses trunk. In three body planes, the translational and rotational movement of the horses trunk results in a consistent pattern of movement with striking points while jumping. In translation, there is a maximum dorsal acceleration of the fore limbs and of the hind limbs in take-off as well as of the fore limbs in landing in sagittal direction. In longitudinal direction, caudal and cranial maximum values of the fore limbs and the hind limbs in take-off are visible. Additionally, with the rotation, velocity around the body width axis at takeoff (dorsal), in suspension (ventral) and after landing (dorsal) are clearly detectable. The translation in the transverse direction as well as the rotation around the body length and body depth axis do not result in evaluable movement patterns. Other important parameters like the velocity of approach, takeoff and landing as well as the take-off and landing distance and angle cannot be obtained from the inertial data. Comparing the results of the different horses, a main effect due to the individuality of each parameter (p0.05) and “Approach" (p>0.05) can be shown. The illustration of take-off and landing velocity, distance and angle of the horses trunks in take-off and landing as well as the approaching speed by integration of the inertial data is not possible yet. The drift of the sensors is too high. In conclusion the inertial measurement system appears to be suitable to present jumping kinematics in the field. The conducted investigation implies the possibility to compare the intra-individual kinematics of horses trunks in show jumping. Because the measurement error accumulated rapidly over measurement duration, the gyroscope data cannot be used to determine the sensor s orientation. To shorten the measurement duration, a known integration constant close to the take-off position is necessary. Further examination with a larger number of horses is necessary to evaluate and interpret the inertial parameters in relation to individual performance. Additionally, physical properties of each sensor, possibilities to determine IMUs orientation as well as the accuracy of the whole measurement unit have to be proofed in order to create a fitting filter system for an autonomous self-tracking system. Therewith, the usage of the IMU saddle belt without an external source as well as the illustration of the kinematics in relation to the world-coordinate-system become possible. Otherwise, kinematic data in relation to the sensor-coordinate-system has to be evaluated in a further investigation with a larger number of horses in order to explain the coherence to performance and success. [ABSTRACT FROM AUTHOR]

The anatomical axes of the body parts and the mechanical axis of the lower extremity play a central role for the load transmission from hip to femur and tibia. These axes essentially determine both the statics and kinetics of the lower extremity. The movements of the joints (kinematics), however, are essentially determined by the anatomy and morphometry of the body parts. The maximum movement capacity of the joints is rarely exploited in the physiologic movement of the joints. Finally, the resulting forces and moments which act on the bones and the joints are partly determined by the weight and the inertia of the body parts. The major contributor to force and moment, however, results from the action of the muscles. The muscle forces and their action through short lever arms explain the substantial loads in hip and knee. [ABSTRACT FROM AUTHOR]