Key Engineering Materials Vols. 474-476

Abstract: Calculating the value of ecosystem services may improve economic efficiency and play an important role in protecting ecosystems.The grassland ecosystem of HulunBuir city is an important component of ecology security system in Northeast China and is the typical belt transect of International Geosphere Biosphere Programme global change study. In this study, net primary productivity (NPP), as an improtant ecological parameter, was used to estmate the services value. Considering the characteristic of satellite imagery, it is difficult to calculate some functions. So we calculated the services value from four aspects, including soil erosion control, water conservation, direct production and gas regulation. The total services value of grassland ecosystem was estimated in RMB to be aproximately 18.47×10⁹Yuan in 2006 (Chinese currency, 7.78 Yuan=US$1), the average economic value of unit area was 15.4×10⁴Yuan/km². The direct production value was 1.23×10⁹Yuan/year; and the contribution rate to total value was 6.66%. Indirect services value was 17.24×10⁹Yuan/year, and the contribution rate to total value was 93.34%. Indirect services value was far more than direct production value. For the indirect services value, the water regulation value was the maximum, 9.09×10⁹Yuan/year. Gas regulation value was 5.25×10⁹Yuan/year, contributing 28.42% to the total value.

Abstract: In this paper we first establish a dependency matrix over the inputs of web services in composition and the degree of dependency between the interface parameters for a single web service. Operating over the matrices, the ripple effect of a single service's fault at runtime has been analysed and computed. Based on this, we have looked for a method to substitute the failing service with an equivalent one at runtime. Using simulations and real examples we have confirmed the effectiveness of the method shown in this paper.

Abstract: Aiming at the current situation of manufacturing enterprises’ resources, the definition and the classification of manufacturing resources are given out. Combining with the dominance of ontology in knowledge reuse and sharing, the ontology classification hierarchy tree of the standardized part resources is defined. By analyzing the properties information of rolling bearing, its ontology model is established based on OWL. The OWL model can reflect better the essential relationship and the semantic relations between concepts, providing a good informationization foundation for manufacturing resources discovery, reuse and sharing.

Abstract: An improved envelope analysis approach based on spectral kurtosis (SK) and complex shifted Morlet wavelet in the diagnostics of local gear faults is proposed in this paper. For enhancing impact signals of gear faults, a prewhitting process is performed to the original signals by autoregressive (AR) models firstly in the approach. Then, the envelopes of signals are extracted by Morlet wavelet filter family and the optimal center frequency and bandwidth of the band-pass filters is determined by SK. In the improved approach, not only the optimal parameters of the band-pass filters in envelope analysis can be obtained adaptively by, but also the number of the required band-pass filters can be reduced dramatically. Simulation results verified the feasibility of the present scheme positively.

Abstract: The dynamic programming has significant implications for solving multi-stage decision of resource allocation problems. By inducting phase, state of variables and decision, the factory assembly line resource allocation problems was taken as a multi-stage decision process. The stage of resource allocation was divided in reason, and the dynamic programming equation was built with “Top-Down” ways to reverse recursion according to the dynamic programming principle and methods. Adopting the MATLAB7.0 as development platform, it was convenient for calculating optimal decision sequence and maximum total profits. Dynamic programming method has obvious effect in equipment resource allocation output issues, and brings in the biggest economic benefits in limited investment.

Abstract: The bad degree of meat and the color change have a close relation. Computer vision is not under the influence of physiological and psychological factor of person; Appraisement standard is objective and steady. Therefore, computer vision system has been established, which can do collection, management, display, and appraisement of porky color. The CIEL^*a^*b^* and CIEDE2000 color difference formula were introduced into the classification of pork, the result was identical. Because the calculation course of CIEDE2000 color difference is complex, so the CIE1976L^*a^*b^* color difference is still adopted to calculate color change at actual production.

Abstract: This paper deals with a thermodynamic analysis of a vapor compression refrigeration system with the new refrigerant R125/R600a blends, parameters and factors affecting the performance are investigated, and also a comparison with that of R22 is presented. Encouraging results are obtained, at a certain concentration of R125 in mixtures, the R125/R600a refrigerant blends perform better than R22 but with loss of volumetric cooling capacity in air conditioning applications. Which may provide useful information for alternative refrigerants.

Abstract: This paper presents a coherence structure construction method based on discourse cue phrases for Chinese text. An algorithm that derives the coherence structure from classes of coherence relation is illustrated, and classes of coherence relation can be concluded empirically by cue phrases of discourse. The experiment result shows that the algorithm can find most of the important coherence structure. It is useful for text analysis.

Abstract: Many products selling on the Internet channel include music, which also sells in brick and mortar stores and in online stores, developed from digitalized music. This study attempts to explore which influence among the service quality, content quality, and the website service quality affects the paying customers’ satisfaction, and studies the relationship of customer satisfaction and customer loyalty. Further, the study probes the factors of customer relationship management. The research framework is based on the customer relationship management of digital content industry model. Results revealed that privacy, system availability, service provider’s reliability, perceived enjoyment, perceived ease of use, and fulfillment significantly affects consumers’ intentions to be paid-members of online music services.

Abstract: In order to decrease the heat rejection pressure of pure CO₂ refrigerating system and meanwhile have sustainable environmentally benefits for working fluild, several natural zeotropic CO₂/Propane mixtures are applied to heat pump system to investigate the heating performance. The heat rejection pressure of CO₂/Propane mixtures is reduced when the mass fraction of carbon dioxide is decreased. Under the given conditions, there is an optimum range of mass fraction of CO₂/Propane of which the mixtures have superior heating coefficient of performance. The temperature glide characteristics of CO₂/Propane mixtures at heating mode was also researched to analyze the heat transfer efficiency. Both a sufficient heat exchange area and a good working fluid’s temperature gradient matching with that of the secondary heat transfer fluid contribute to a higher heat transfer efficiency of heat exchanger.