Applied Mechanics and Materials Vols. 295-298

Abstract: 31 of China’s provinces was divided into seven categories by a process of collecting data, standardizing data, creating fuzzy similarity matrix and fuzzy equivalent matrix, and finding the threshold value. There is not strictly positive correlation between environmental pollution and economic growth in China’s provinces. Because of different industry development policy and industry feature, environmental pollution in some more developed provinces and cities is less serious, while that in some provinces of the intermediate level is more serious.

Abstract: The paper discusses the environmental monitoring methods and the existing problems, and then pointed out four aspects in need of improvement: environmental monitoring network needs to be improve; data analysis need to be further; environmental quality comprehensive analysis capability need to strengthen; monitoring instrument needs to be updated. And using the Internet of things technology, combined with the technology of RIA, WebGIS, in Flex Viewer open source framework, adopted the open design, discusses a suitable environment real time monitoring and early-warning of the combination of hardware and software of network application system. It can provide a feasible solution for environment monitoring and early-warning.

Abstract: This paper studies environmental information monitoring and put forward structure scheme of embedded environment monitoring system based on Ethernet. Using C/S structure network design, the client site monitor nodes, real-time collect environmental information data and local preservation, through the Ethernet upload information to the server. Monitoring nodes are controlled by LPC1766 chip, the chip manage the node’s data acquisition, storage and transmission. Using μC/OS-II embedded real-time operating system as the client software platform, the experiment test results show that the system can effectively implement environment monitoring.

Abstract: The pyrolysis of oxidized mercury is one of key techniques for the conversion of species mercury from ionic form to elemental form. At present, thermal pyrolysis technique has been more and more used in on-line total gaseous mercury monitor for its high conversion efficiency and less time consuming maintenance. We investigate the pyrolysis efficiencies of oxidized mercury using SiC, nickel (Ni) and nichrome as thermal conversion materials in converter. The results reveal that compared with SiC material, the nickel (Ni) and nichrome can provide high pyrolysis efficiency. Particularly, the nichrome that contains 15% chromium (Cr), 75% Ni and 8% Fe can achieve 8.7% higher conversion efficiency than SiC at 800 °C. The results demonstrate that the nichrome that contains 15% chromium (Cr), 75% Ni and 8% Fe is an appropriate thermal converting material for the on-line total gaseous mercury monitor.

Abstract: The long propagation delay in underwater acoustic sensor networks renders existing media access control (MAC) protocols for terrestrial wireless networks undesirable. In this paper, we propose a new cooperative MAC protocol for underwater sensor networks that is used to detect objects and monitoring the environment. Our proposed MAC protocol tries to prevent data collisions through short term scheduling among neighbor nodes with exchange of short data message. By adapting the all sensor nodes to the transmitting schedules in which time is optimized we can minimize the collision rate between nodes. Through simulations, we show our proposed protocol can minimize data collisions and not only offers a higher throughput, but also indicates a better end-to-end delay.

Abstract: In the process of water quality monitoring based on microscopic examination of the activated sludge, low-contrast images can be captured sometimes when manual observation is being replaced by automated observation based on machine vision. It is difficult to accurately detect the target complete edge in a low-contrast image with a single image-segmentation method. The idea provided is in the paper that the low-contrast image is firstly segmented by Canny operator and mathematical morphology respectively, and then the two segmented images are fused based on wavelet transform. In order to verify the idea, the tail spines insect image shot by digital microscope is processed according to the idea in the paper. The result shows that this idea can achieve better image edge detection effect and it will provide good technical basis for the next protozoan and metazoan identification and statistics.

Abstract: Modeling and optimization of NOx emissions is an important task of boiler combustion optimization. Nonlinear modeling techniques with adaptive mechanisms and the genetic algorithm for optimization are all used widely. The purpose of this study is to achieve successful application of modeling and optimization for NOx emissions of fossil-fired boilers. In this paper the adaptive modeling techniques and genetic algorithm will be integrated and applied on the NOx emission data of two different utility boiler units.

Abstract: With Mann-Kendall non-parametric test and spatial interpolation methods, the research has explored the spatial and temporal characteristics of changes of wind erosion climatic factor C within 58 years in Shandong province. The annual average C value of the province is 163.57 with the peak value occurred both in Yantai, Weihai cities and the central area. The Yellow River flood plain, which is the most serious wind erosion district, only lies between 50 ~200. The average C value has shown a significant downward trend in the entire province for 58 years, and the peak occurred in 1962 and valley value occurred in 1990. The C value has shown a downward trend in most area of the province, among which the decrease of areas centered on Ji’ning is the greatest and reach -7/a. On the Yellow River flood plain, the C value also shows a regional difference declining trend.

Abstract: In water quality early warning system based on the abnormal behavior of fish, the core technology is building the fish movement model and obtaining the movement parameter based on this model. The fish body image accurate segmentation is the key to the implementation of this core technique. The single edge detection method can not accurately detect fish all edges. In the paper, the proposed solution is that the original image is firstly segmented by Canny operator and Log operator respectively and then the two segmented images are fused based on the wavelet transform. The fused image will obtain more complete target information from the two segmented images. The fish image acquired by the machine vision is processed according to the idea. The result shows that this method can obtain better edge detection effect. It will provide technical support for the live fish movement modeling.

Abstract: Based on continuous observation data of two cross-sections among 2007-2010 in Tuo River of Suzhou, investigated the distribution characteristics of TN、TP and NH₄⁺-N pollution. The result shows that TN、TP and NH₄⁺-N variation between 0.1-14.39 mg/L、0.029-0.89 mg / L and 0.011-5.72mg / L. Beside, the investigation appeared that annual average change is in the state of upward trend; seasonal changes is significant, but has no notable regularity. Related analysis shows that the water temperature correlated weakly with the water volume、TN、TP and NH4+-N. Conclusions indicate that human activities in the region of Tuo River influence TN、TP and NH₄⁺-N pollution situation and point source pollution is a major influence factor.