New structure transcutaneous transformer for totally implantableartificial heart system

A new structure transcutaneous transformer for a totally implantable artificial heart is presented which has a high coupling coefficient and transmission efficiency. Experimental results indicate that it is possible to transmit an electrical energy of 20 W transcutaneously with a maximum efficiency of more than 90%     

Performance evaluation of random power capture on mobile communications

Power assignment schemes are man‐made methods to enhance the capture effect of radio communications. In a previous study, Wen and Yang investigated the combined capture effect of the fixed power assignment scheme, Rayleigh fading, and near–far effect on the performance of packet radios. The performance analysis was limited to an infinite population environment. This assumption is reasonable for a conventional packet radio system with a vast service area. However, for a cellular mobile system, a finite population model should be used. In this paper, we analyse the combined natural and man‐made capture effect on the performance of a cellular system with finite population in each cell. A random power assignment scheme is adopted to produce the man‐made capture. The system throughput and delay are carried out by a Markov model. Some numerical calculations are used to demonstrate the degree of performance improvement. Copyright © 2001 John Wiley & Sons, Ltd.     

An efficient finite-difference-based Newton-Raphson method to determine intrinsic complex permeabilities and permittivities for Mn-Zn ferrites

This paper presents a fast and efficient algorithm, based on the finite-difference method, to extract intrinsic complex permeability and permittivity from measured values for Mn-Zn ferrite cores. Our algorithm is considerably more efficient than the analytical solution-based Newton-Raphson method and reduces computing time from hours to tens of seconds.     

A field study on 8 pharmaceuticals and 1 pesticide in Belgium: Removal rates in waste water treatment plants and occurrence in surface water

Only recently, attention has been drawn towards the occurrence of pharmaceuticals in the environment. In recent years many reports have been made on the occurrence of the large, differentiated group of pharmaceuticals in waste water, surface water, ground water and in soil. In this study, we demonstrate the applicability of a previously developed LC-MS/MS method by evaluating in waste water and surface water samples from Belgium the occurrence of 8 pharmaceuticals and 1 pesticide (flubendazole, pipamperone, rabeprazole, domperidone, ketoconazole, itraconazole, cinnarizine, miconazole and propiconazole). Removal rates in five public waste water treatment plants were assessed. Introduction of several compounds into the aquatic environment by discharge of effluent could be demonstrated. For several compounds, the highest concentrations (up to 35.6 μg/l for pipamperone) were observed in the effluent of a WWTP receiving water from chemo-pharmaceutical and other industrial companies. The occurrence of these compounds in the aquatic environment was assessed by analyzing 16 surface water samples, taken from various locations. Four pharmaceuticals (flubendazole, pipamperone, domperidone and cinnarizine) could be detected in at least one sample at low concentrations (up to 26.4 ng/l). The pesticide propiconazole was found in comparable concentrations (up to 85.9 ng/l) as in effluent, suggesting potential introduction by direct seepage of water from rural grounds. The highest concentrations of flubendazole, pipamperone, domperidone, propiconazole and cinnarizine (up to 961.3 ng/l) were observed in a sample, taken near the discharge of a WWTP receiving water from chemo-pharmaceutical and other industries. An initial environmental risk assessment was done based on these results.     

The study of α in GM(1,1) model

Abstract

The purpose of this paper is to analyze a predicted error in using the GM(1, 1) model based on the parameter α. The transfer function for the predicted error with the parameter α in the GM(1, 1) model is presented. The algorithm of solving equations in calculus is used to analyze whether the α is adaptive or not. The criterion of α is applied to describe the adaptive criterion of α. Finally, an example of the cagenet amounts of fish in the Peng‐hu area is used to demonstrate the small prediction error due to the optimal α value. The result shows that the criterion for α is applicable for minimizing the predicted error easily.     

铁路化工罐车的高压水射流清洗

介绍了铁路化工罐车的高压水射流清洗系统构成和工作原理．确定了影响高压水射流清洗铁路化工罐车质量的基本参数．对高压水射流清洗工艺与传统的蒸洗工艺作了对比,说明了高压水射流清洗工艺效率高、清洗质量好,特别是解决了过去蒸洗工艺造成的环境大气污染     

Bending actuation and charge distribution behavior of polyurethane/carbon nanotube electroactive nanocomposites

The electroactive nanocomposite films were fabricated using polyurethane (PU) with modified carbon nanotubes (CNTs) as the filler. The CNTs were modified using microwave‐induced polymerization route and they were found to be highly dispersed in polar solvents such as dimethylformamide. The modified CNTs were characterized using transmission electron microscopy, field emission scanning electron microscopy, thermogravimetric analysis, and X‐ray photoelectron spectroscopy. To evaluate these films we mainly focused on electrical properties such as actuation behavior, resistivity, impedance analysis, and space charge measurements. We found that the PU/CNT films bent toward the cathode when an electric field was applied and they reverted to its original position when the electric field was removed. Upon the incorporation of CNTs as the filler for the polymer, the electrical properties of the films improved significantly. Asymmetric charge accumulation was observed from space charge measurements in some of the films and this explains the bending deformation and the actuation behavior. POLYM. COMPOS., 262–269, 2016. © 2014 Society of Plastics Engineers     

Design and control of a novel flywheel energy storage system assisted by hybrid mechanical-magnetic bearings

It is the intention of this paper to propose a compact flywheel energy storage system assisted by hybrid mechanical-magnetic bearings. Concepts of active magnetic bearings and axial flux PM synchronous machine are adopted in the design to facilitate the rotor–flywheel to spin and remain in magnetic levitation in the vertical orientation while the translations and rotations along and about x and y axes are constrained by mechanical bearings for simple operation. In this paper, the mathematical model of the flywheel’s levitation force and rotational torque is developed. The control systems of the position and velocity of the flywheel are designed based on PID method. Experiments are carried out and its test results prove the feasibility of the proposed flywheel system concept, the correctness of the mathematical analysis and the validity of the designed control system.