In recent years, car-hailing service has been rapidly developed in China, especially in the first tier cities such as Beijing, Shanghai and Guangzhou.Thecharge of car-hailing service is based on the service mileage.Therefore, it isimportant for the car-hailing service platform to calculate the service mileage accurately. In a given period of time, the service mileage equals to the summary of distance between adjacent positioning coordinates.In this paper, a research is made to study the relationship between the positioning error of adjacent positioning coordinateand the error of corresponding mileage. Vehicle experiment is carried out in five kinds of typical road conditions, which contains “elevated road above”,“elevated road below”,“tunnel”, “shade” and “open-air”. The results show that the difference between the positioning error of adjacent point has great influence on the cooresponding mileage error in the same period.

A hollow dielectric resonator has been developed for the measurement of either the conductivity or the permittivity of bulk samples in form of small cylinders. The setup could be used to measure the dielectric permittivity of low-volume liquid samples. Open and closed (Hakki-Coleman) configurations are presented.

Controlling the environment is a critical component of quality assurance in laboratories. That is because in many cases the environmental condition can severely alter the quality of results. In other cases, having complex systems operating in a non-compliant environment can lead to malfunctions or decreased life-span of those systems. This is exactly the case of large medical or molecular biology or laboratories. Typically, most available commercial solutions are comprised of a set of sensors and a system logic which decides to override and reprogram the maintenance systems to return to desired conditions. This article introduces a simple and robust intelligent system with a feedback loop for monitoring and alerting in the scenario the environment parameters get out of range. Besides continuous display, visual and sound alerts, the system is equipped with the possibility of sending SMS-notifications to a given set of phone numbers (remotely located human administrators) with delivery of current environmental out of range parameter values. Threshold values can be easily redefined since the system has a separate initialized file containing all the configurable parameters and scenarios.

Permanent magnets have wide applications in all important fields of our modern technology; they became indispensable in automotive industry, aerospace, acoustic, telecommunications, energy generation and in many more. Physically the permanent magnets are metastable systems. Fluctuations in the composition and of the processing parameters can cause fluctuations of the magnet properties. To obtain the optimal performances of their applications, the users are requiring careful controlling of non-machined parts as well as of the finished machined magnets. In most of the cases, measurement records of the final control of the assembled magnetic systems have to be performed. The aim of this paper is to review most typical measuring methods used for the magnetic properties of the permanent magnets, to comment their advantages and their limits and to discuss the accuracy which can be achieved.

A previous work, published in ACTA IMEKO journal, pointed out the attention about probable variability performing track to ground conductance measurements, using the method indicated in the A.3 of the IEC 62128-2 international standard. In this work the presence of such measurement variability has been proven by on site measurements.