Advanced Materials Research Vols. 765-767

Abstract: Shipborne measurement and communication equipments are central parts of space measurement ship. Renewal of the equipments is very important for space measurement tasks. Also it is important to save cost for continual development. The paper proposes the problem of technical and economic analysis of the renewals. The maintenance and update with their analysis are introduced too. Finally schemes of the renewal and its decision-making method are presented. The renewals are motivated mostly by requirement of space missions at present. But for continual development the ratio of efficient and cost is important. The decision-maker may refer the paper and select scientific renewal scheme.

Abstract: The previous measuring methods have the disadvantages of big workload, inaccuracy, high expenses and so on. A set of remote monitoring system that monitors soil moisture is developed by configuration software. This system makes online monitoring soil moisture, dynamic display of real-time data, historical data query and remote access come true. The test results in Haikou show that the system not only meets the requirements of monitoring soil moisture, but also is featured with good stability, accurate data and data sharing. It can be applied in many fields when changing the necessary sensors. The system is scalable and low-cost.

Abstract: This work studies eco monitoring networks. As eco monitoring networks have been used to monitor large networks, questions arise whether decentralized inference is efficient and whether an eco monitoring network with a moderate size can monitor an underlying network at the Internet scale. This work studies the local effectiveness of decentralized inference done by individual monitors. Information theoretical measures, i.e., conditional non-uniformity factor is applied to quantify the effectiveness. Large-scale data from DShield is used to access the effectiveness of a real eco monitoring network.

Abstract: in the thesis we introduce fuzzy mathematic method into fault diagnosis of hydraulic pressure system, bring forward the fuzzy membership grade method which is based on the history data and expert preferential ordinal number, set up a mathematical model of fault diagnosis, and carry out the fuzzy diagnosis on hydraulic pressure system fault in computer. The example shows that this method is advantageous to accuracy and credibility of decision and is valid and viable in the application.

Abstract: in order to satisfy the positioning accuracy identification requirement of MUAV navigation system, the characteristics of visual navigation were analyzed, the existing navigation system accuracy assessment methods were summarized and the conversion relationship of each index were deduced. According to the Ethridge statistical algorithm for calculating circular error probability (CEP), navigation and positioning accuracy assessment scheme were designed. Finally, the time-CEP(TCEP) accuracy evaluation method based on visual measurement was put forward, which were verified by simulation using four group actual INS data .The results show that: the scheme is feasible, convenient and practical; the method can relatively comprehensive evaluate the positioning accuracy of navigation system and can make full use of the single trial data.

Abstract: Lane detection is a crucial component of automotive driver assistance system aiming to increase safety, convenience and efficiency of driving. This paper developed a vision based algorithm of detecting road lanes which is performed by extracting edges and finding straight lines using improved Hough transform. The experimental results indicate that this algorithm is effective and precise. Furthermore, this algorithm paves the way for the implementation of automotive driver assistance system.

Abstract: The quality of diesel truck overall quality is measured through a series of performance indicators. This paper analyzes the complex diesel truck systems through the use of principal component. Through the analysis, several major indicators which affect the truck service conditions are found in many of the performance indicators, and major factors affecting the serviceability of diesel truck are obtained.

Abstract: Power transformers vibration principle was analyzed, using vibration spectroscopy, design and development of a power transformer online monitoring system, through the transformer vibration monitoring, to indirectly infer the DC magnetic bias circumstances, Realized condition monitoring of Substation. This paper describes the system works, the constituent modules and the corresponding indicator characteristics, proposed monitoring algorithm optimization, Given the interface of real-time monitoring data, historical data, system was running good, stable and reliable.

Abstract: We study on the energy detection algorithm of spectrum sensing. The performance of energy detection in spectrum sensing is measured by the false alarm probability and the missing detection probability. In a certain spectrum sharing environment, whether the energy detection algorithm can meet our requirement is depending on the length of observation time and the decision threshold selected. Several experiment results have shown that: when the decision threshold is too low, it will cause much more false alarm; when the decision threshold is too high, it will bring many missing detection. Therefore, it is crucial that choosing an optimal decision threshold according to the length of observation time. In this paper, the closed-form solution of the minimum-cost decision threshold is deduced by using the methodology of mathematical derivation, and a new criterion about selecting an optimal decision threshold is also proposed. At last, the conclusion is proved by simulation.

Abstract: Allelopathic effects of dried macroalga Ulva pertusa (Chlorophyta) on photosynthesis of the microalgae Skeletonema costatum (Bacillariophyta) were evaluated using coexistence culture systems. S. costatum was cultured with different biomass of dried U. pertusa under controlled laboratory conditions for three days. The chlorophyll a (Chl a) fluorescence transient O-J-I-P curve coupled with its specific parameters in S. costatum was established. The Chl a fluorescence transients were recorded in vivo at high time resolution and analyzed according to the JIP-test which can quantify photosystem II activity. A clear dose-dependent relationships were observed between the dried biomass of U. pertusa and its inhibitory effect on S. costatum. A decrease in the O-J-I-P curve expressed as Chl a fluorescence intensity along with its specific parameters were observed, which was also time-dependent. The main photosynthetic inhibitory targets of the macroalga on the microalga, according to the JIP-test, can be expressed as a decrease in the number of active reaction centers and the blocking of the electron transport chain. The results of the present study suggest that dried fragments of U. pertusa effectively inhibit photosynthesis in S. costatum.