Effects of some chemical detergents additions on concrete

Usually, the drainage network made of concrete and which fall under the infrastructure in cities. This research aims to study the corrosion of cement concrete under the influence of Washing Detergents, as well as determine the negative influence on some properties such as weight and mechanical resistance. The results showed that sodium phosphate salts by 27-35% of the weight of the detergent has led to weaken the resistance of the pressure of the cement mortar by 5%, and sodium sulphate salts and sodium chloride led to weaken on pressure resistance and inflexion by 15%. Corrosion Index showe proposed sharp decline very resistant to detour - the pressure resistance by up to 30%. Keywords: Concrete. Detergent. Corrosion. Resistance. Mechanical resistance, Weight. Index

Evaluation of Communication Induced Checkpointing Approaches for Reconfiguration-Based Fault-Tolerance in Embedded Systems

Reconfiguration-Based Fault-Tolerance is an approach to developing dependable safety-critical embedded applications, where redundant active or standby resources are used to cope with faults through a system reconfiguration at run-time. Compared to traditional hardware and software redundancy, it is a promising technique that may achieve dependability with a significant reduction in cost, size, weight, and power requirements. Reconfiguration necessitates using proper checkpointing protocols to support state reservation to ensure correct task restarts after a system reconfiguration. Communication Induced Checkpointing (CIC) protocols are well developed and understood for large parallel and information systems, but not much has been done for resource limited embedded systems. This paper implements four common CIC protocols in a resource constrained distributed embedded system with a Controller Area Network (CAN) backbone. An example feedback control system implementation is used for a case study. The four implemented protocols are described and performances are contrasted. The paper compares the protocols in terms of network bandwidth consumptions, CPU usages, checkpointing times, and checkpoint sizes in additional to the traditional measures of forced to local checkpoint rations and total number of checkpoints

Estimating Willingness-To-Pay for Reduction in Uncertainty in Water Quality of Contaminated Aquifers

Management of contaminated aquifers is challenged by the limited resources available to monitor and remediate a large number of contaminated sites. Earlier research recognized the negative impacts of spatial data scarcity on the success of aquifer monitoring and remediation plans. Therefore, there exists an important question on how to allocate limited resources to collect additional information to better estimate the risks and remediation priorities versus the willingness to pay by the society. This work introduces one of the early applications of structural benefit transfer to quantify welfare impacts of improving aquifer monitoring in terms of willingness-to-pay (WTP). This work uses health risk assessment methodology and introduces a practical socio-economic framework to estimate individuals’ WTP for a proposed improvement in data gathering. The proposed methodology develops scenarios of uncertainty reductions in subsurface heterogeneity by collecting additional spatial data to reduce health risk to target population and computed the health-economic impact to estimate the aggregate WTP. The variability of characteristics of the target population is represented through probabilistic distributions of income, health state, age, and risk exposure parameters. The proposed methodology produced predictions of WTP that are consistent with the patterns expected in the economic theory and literature. Keywords: Groundwater, contamination, uncertainty reduction, additional data, Willingness-to-Pa

The environmental impacts of calcium chloride addition to cement on reinforcing steel corrosion

An alternative use of a specific type of cement for a particular purpose, usually we can change some properties of available cement by using the appropriate additions, with some negative side effects in some cases. In this research have been suggested values ??of calcium chloride(CaCl2) additions for use in concrete admixtures as an agent factor in accelerating the process of cement setting, to clarify the extent of the negative impacts that could be induced, such as alkalinity decline of solution and the impact of the chemical composition of used cement on reinforcing steel. Chloride ion present in low alumina cement mortar was detected quickly, while it needed to increase calcium chloride content to double in moderate alumina cement mortar. The results showed that the depth of carbonation when samples of different composition and with various w/c ratio treated by stream was faster in low ammonia cement mortar from moderate ammonia and faster in mortar poor than in mortar rich, In addition, depth of carbonation increased when the calcium chloride content in cement was very small. Electrical potential of steel in cement mortar inversely proportional with increasing calcium chloride content and with increasing in water/cement ratio and increasing sand content in cement mortar medium ammonia. The lowest level of steel oxidation observed in mortar consisting of cement medium ammonia and the rate of corrosion increases when samples treated by stream in all cases. Keywords: Calcium Chloride, Oxidation, Reinforcement, Stream Treatment, Carbonation, Concrete admixtures, Electric potentia

Wearable IMU for Shoulder Injury Prevention in Overhead Sports

Body-worn inertial sensors have enabled motion capture outside of the laboratory setting. In this work, an inertial measurement unit was attached to the upper arm to track and discriminate between shoulder motion gestures in order to help prevent shoulder over-use injuries in athletics through real-time preventative feedback. We present a detection and classification approach that can be used to count the number of times certain motion gestures occur. The application presented involves tracking baseball throws and volleyball serves, which are common overhead movements that can lead to shoulder and elbow overuse injuries. Eleven subjects are recruited to collect training, testing, and randomized validation data, which include throws, serves, and seven other exercises that serve as a large null class of similar movements, which is analogous to a realistic usage scenario and requires a robust estimator

Visualizing shear bands in 3-D using axisymmetric sample: An experimental study

In this study a qualitative description of the occurrence of shear bands produced by a sudden impact on an axisymmetric specimen made of medium carbon steel 0.45% C is given. A simple experiment was developed aimed at producing a pinch shear stress in the front side of the test sample in order to visualize shear bands in 3-D. Curve fitting using MATLAB was employed based on the points taken from the images of the front section of the test sample. The predictions of the curve fitting suggests a hyperbolic section leading to the conclusion that within the sample there is a double cone region of material where the shear band region is located on its outer surface. The formation of the shear band is explained by the fact that the interaction of the stress wave front with the free surface of the test sample produces reflection waves that attenuate the incoming stress wave inwards leading to a stress gradient in the plane of the front side of the specimen that causes shear localization. Also, the progressively increasing cross sectional area of the test sample causes the expansion of the wave front, which also results in a stress gradient in the normal direction of the front side of the specimen. So the formation of shear bands depends not only on the impact momentum and strain rates but also on the sample\u27s geometry. \ua9 2015 The Author

Highly-Individualized Physical Therapy Instruction beyond the Clinic Using Wearable Inertial Sensors

Musculoskeletal conditions, often requiring rehabilitation, affect one-third of the U.S. population annually. This paper presents rehabilitation assistive technology that includes body-worn motion sensors and a mobile application that extends the reach of a physical rehabilitation specialist beyond the clinic to ensure that home exercises are performed with the same precision as under clinical supervision. Assisted by a specialist in the clinic, the wearable sensors and user interface developed allow the capture of individualized exercises unique to the patient’s physical abilities. Beyond the clinical setting, the system can assist patients by providing real-time corrective feedback to repeat these exercises through a correct and complete arc of motion for the prescribed number of repetitions. An inertial measurement unit (IMU) is used on the body part to be exercised to capture its pose. In this paper, we present a kinematics data processing approach to defining custom exercises with flexibility in terms of where it is worn and the nature of the exercise, as well as real-time corrective feedback parameters. The system is tested on two exercises performed by a healthy individual to demonstrate the feasibility and accuracy of the approach. We demonstrate how it can improve exercise adherence by assisting users in reaching the full prescribed range of motion and stay on the ideal plane of motion and improve hold time. Preliminary results from an ongoing clinical trial are presented