Applied Mechanics and Materials Vols. 511-512

Abstract: This paper deals with the study of factors which are affecting basis weight sensor measuring accuracy, the Z distance, XY dislocation, air gap temperature, dust and paper grades. The calibration techniques and solving methods of accurately measuring are given. Automatic calibration and range division are combined to improve the accuracy of basis weight sensor, and the BW measuring precision is reasonable. Static accuracy (2σ) is 0.20% and dynamic accuracy (2σ) is 0.25% at the range of 10 g/m²-1500 g/m².

Abstract: The normal context-aware applications mainly focus on the information acquisition and processing from isolated sensor nodes or devices, which make the applications lack of the ability of information sharing and cooperation. This paper introduces collaborative idea into intelligent context-aware environment, establishes a common framework and model for collaborative context-awareness, and specifies the workflow of collaborative intelligent sensing. The proposed modeling and processing method can be effectively used in smart home and other application scenarios, which can improve the reliability and accuracy of perception, and improve the efficiency of the context-awareness processing obviously.

Abstract: Traditional sensor fault diagnosis is mainly based on statistical classification methods. The discriminant functions in these methods are extremely complex, and typical samples of reference modes are not easy to get, therefore it is difficult to meet the actual requirements of a project. In view of the deficiencies of conventional sensor fault diagnosis technologies, a fault diagnosis method based on self-organizing feature map (SOFM) neural network is presented in this paper. And it is applied to the fault diagnosis of pipeline flow sensor in a dynamic system. The simulation results show that the fault diagnosis method based on SOFM neural network has a fast speed, high accuracy and strong generalization ability, which verifies the practicality and effectiveness of the proposed method.

Abstract: This paper designed a kind of efficient IOT transmission platform based on wireless sensor network and GPRS network. Using the multi-mode sensor nodes composed of temperature-humidity senor and acceleration sensor, realize the effective detection of geological disaster, such as landslide and debris flow. After experimental verification, the IOT platform based on the two levels of network structures, can effectively transmit the monitoring point's information, such as the surface humidity, tilt angle and displacement. The system has long transmission distance and low power consumption.The system will have certain engineering value in the field of geological monitoring.

Abstract: In order to solve slower testing and lower degree of electronic information in current college entrance physical examination, we designed a basketball goal automatic detector. The designed system consists of single chip microcomputers, ultrasonic and infrared sensors. In this system, the basketball goal can be automatically detected and correctly judged by using ultrasonic sensors installed in the backboard and infrared sensors installed in the basket. The results are displayed in LED via RS485, and at the same time, sent to the upper computer via RS232. Experimental results showed that, compared to the existing systems, the designed system's installing restricts reduced. Enhancing objectivity, reducing labor costs, and more fairness were achieved by using this system.

Abstract: The Coordinated Universal Time (UTC) is the international reference time-scale, and provides the basis for broadcast time signals and for time-keeping in the large majority of countries. In its current form, UTC is computed as the average of a large number of atomic clocks and its scale interval is based on the second in the International System units (SI), but it is adjusted by the occasional insertion of one second (called as leap second), to maintain close alignment with Universal Time 1 (UT1), a time-scale determined by the rotation of the Earth. The UTC system with leap seconds is not a continuous time scale, in resent years, several countries and international organizations have started a discussion on the need to abolish the application of leap second in UTC, however, some countries oppose it. Issues on leap second worldwide are presented in this paper.

Abstract: In order to analyze the influence of the near-ground reflection on aperture coupling, a full-scale model of metal shelter with a lossy ground was constructed. The rules of aperture coupling of the High-altitude Electromagnetic Pulse were researched, while the angle of incidence, the conductance and relative permittivity of the ground were changed respectively. Then the strength of electric field inside the shelter was computed and compared when the shelter was above on different topography. Studies show that the coupling electromagnetic energy strengthen with the incident angle of plane wave increasing. When the conductance and relative permittivity of the ground gain, the main crest of the electric field substantially keeps constant, while the second crest increases dramatically. Sea surface has the strongest reflection of electromagnetic pulse, followed by sand land, then the mud land. The reflection of wet land is much stronger than dry land.

Abstract: Fiber ring resonator is widely used to generate stimulated Brillouin scattering(SBS). In this paper, the resonant condition of the acoustic wave in the ring is discussed, and the condition of simultaneous resonance of multiple cascaded SBSs in a single mode fiber ring is analyzed.

Abstract: Different voltage-class buses of transformer substations which are established based on harmonic voltage distortion to limit amplitude via national standards, so study of harmonic longitudinal propagation (RHLP) is essential to power networks. In order to research RHLP, building models of different electrical components which are harmonic sources, equivalent generators, distribution parameter overhead lines (DPOL), transformers, and loads and so on are crucial. This paper proposes a method which utilizes the principle of electric circuits' ohm' law, series resonance and parallel resonance to study RHLP. Finally, according to Henan province power networks frame, a model is constructed in the simulation software packages PSCAD/EMTDC to verify the method. Furthermore, using MATLAB calculation and PSCAD/EMTDC simulation conclude RHLP in different voltage classes.

Abstract: Aiming at the shortcoming of the classical method of optical theodolite projection intersection named ́R ́ method and traditional data fusion method named point-by-point EMBET method, this paper advances the function restriction EMBET method which is based on multi-optical theodolites. Comparing with the three methods by simulation experiment, it demonstrates that the function restriction EMBET method has higher positioning accuracy and stronger practicability than two traditional methods. Furthermore, this method supplies the important reference value for engineering application.