Applied Mechanics and Materials Vols. 496-500

Abstract: Flight delay is a serious problem which many airlines encounter. This paper studies on flight delay problem based on the thought of adaptive agent digraph,and then does the simulation analysis. The indicator of entropy is proposed to measure the uncertainty of flight delay occurrence. The results show that if entropy is not zero, flight delay occurs,and if entropy increases, the possibility of flight delay increases as well as its spread effect. So using entropy as the indicator to reflect the situation of flight delay is feasible.

Abstract: By analyzing the condition of safe deceleration, a new CA traffic model emphasizing high safety was simulated. In order to describe the impact of the safety deceleration on the model, using computer to design and implement safety deceleration CA model simulation program. Computer numerical simulations have been carried out. The flow-density diagrams indicate the increase of flow and the stability of the entire system, and show the presence of meta-stable state near the critical density. With the increase of safety deceleration probability, the traffic flow is higher than that with the former model in the situations of both mid density and mid-low density.

Abstract: The SDNS cellular automata (CA) traffic model is chosen as the method to point out the fault in the original model by analyzing the condition of safety deceleration. An improved CA model is proposed in this paper through adjustment of the evolution steps and the redefinition of safe deceleration conditions. Thousands of simulations have been carried out. Comparing with SDNS model and original safety deceleration model with the proposed model in this paper, when emerging congestion, the combined action of urging and safe deceleration enabled system self-adjustment so that efficiently mitigated congestion. This proves that the stop status of the whole traffic flow has been improved, which have been observed in real traffic.

Abstract: A novel DC corona discharge technology was applied on inactivation of bioaerosol in indoor air. A wide range of initial concentration of microorganisms (from 35×10⁴ CFU/m³ to 3×10⁶ CFU/m³) was tested to show excellent germicidal properties for its high inactivation efficiency. Over 99.997% of microbe into the reactor were inactivated at t=150s, E_P 2kV/cm and initial population was 3.0×10⁶ CFU/m³. The effects of active species produced by a DC corona discharge on the inactivation of a mixture of bacteria in flowing aerosol were proved. The active radicals like OH radical which acted on microbes in the way of direct oxidation were the most significant factors influencing the microbe inactive efficiency through the assessment of heat variety, ultraviolet emission and ozones generation. The active radicals generation in the process of sterilization can be simply controlled by regulating applied voltage before ozone generated. The results indicate that use DC corona discharge technology in the future application of indoor air decontamination.

Abstract: Risk-based corrective action (RBCA) is a scientifically-accepted approach to remediate polluted sites. Under the RBCA approach, the risks to human health associated with polluted sites are assessed and appropriate remedial measures are taken to reduce risks. RBCA evaluations involve the use of risk models to assess health risks to different receptors. In Taiwan, the Soil and Groundwater Remediation Act was enforced in 2000. The government of Taiwan also use risk assessment protocols to obtain acceptable remediation goals for polluted sites with low risks. In this study, the application of risk assessment to derive remediation goals and develop remedial strategies at a fuel-oil spill site were performed. After the risk evaluation, the soil and groundwater remediation goals for total petroleum hydrocarbon (TPH), benzene, toluene, ethylbenzene, and xylenes (BTEX) were determined. The remediation levels meet with the requirements for minimum target risk levels (cancer risk = 1×10^-6 and hazard quotient = 1). The developed risk-based cleanup goals are calculated based on actual land use and exposure pathways rather than on assumed maximum exposure. After the completion of RBCA process, the remediation cost can be significantly reduced. Based on the risk assessment results, source zone remediation, natural attenuation, and long term monitoring were recommended as the remediation strategies of the studied site to reduce risks to human health. Results from this study provide a streamlined process for future risk assessment work at petroleum-hydrocarbon polluted sites in Taiwan. RBCA is a sound and defensible basis for site closure, and it offers a more logical framework for making site closure decisions.

Abstract: To airlines, the network profit is the fundamental and the only goal pursuit. When airlines operates the airline network, it is the most direct means to ensure passenger flow on every route, in addition to use large models, increase the frequency, developing competitive airline fares will also attract more passengers. As for the hub and spoke network, there are direct flights and the transit flights, each side of the flow varies with the fares and the number of network nodes, in order to highlight the scale economic benefit of hub and spoke network, research on the influence of network edge flow, fares on route network the profit is very important.

Abstract: Urban forms are shaped under transport-land use connection. According to literature reviews, urban forms can be divided into six kinds from 1880 to 1990, traditional walking city, industrial transit city, automobile-oriented development city (compact or sprawl), transit-related development city and transit-oriented development city (TOD). Although many cities in the world had attempted to shape their urban forms like TOD in the 1990s, they didnt have definite goals and strategies to achieve it. On the other hand, there is neither systematic discussion nor comparative analysis concerning how to determine the original urban form of these cities. In this case, it is unlikely for them to become a TOD city in effective and suitable ways. As a sequence, this paper aims at reviewing literature , designing two sets of strategies to shape TOD urban form for policy-makers reference.

Abstract: This paper presents a method to create the traffic accident scene graphic based on electronic maps and information acquisition device (IAD). The method uses global position system (GPS) and electronic maps to get the satellite images of accident site, and it uses an IAD to obtain the angle and distance data between the origin position determined by the IAD and the locations prepared to be measured in the accident scene. With the data operation and image processing, we can create an isometric traffic accident scene graphic. This method provides the traffic accident spot data collecting, graph drawing and reason analyzing a more convenient and scientific technical means.

Abstract: The aim of this study was to investigate the use of a remote-sensing model to compute a hybrid rotation period of multi-crop rotation in large area. The model was constructed to compute the hybrid rotation period of cotton-rice and cotton-others of 38 towns in XingHua City, Jiangsu Province, China. The rotation periods for cotton-rice and cotton-others were computed as 2.09 and 3.38 years using the data from satellite remote sensing images. The results were shown to lead to a hybrid rotation period of cotton-rice and cotton-others of 1.24 years. This indicates that there is a possibility of managing multi-crop rotation in large area from hybrid rotation periods and suggests that it is possible to measure crop growth status in large area with hybrid rotation periods to make management decision for crop diseases.

Abstract: We take Shunde District, Foshan City in Guangdong Province for example, to carry out SWOT analysis of urban greening maintenance and management. The strengths of greening management and maintenance in Shunde District are as follows: (i) The greening area and quality are continuously improved in the downtown of Shunde District; (ii) The management and maintenance work is carried out well; (iii) The management and maintenance level tends to be increasingly perfected. The weaknesses of greening management and maintenance are as follows: (i) The fees for greening management and maintenance are very low; (ii) There is corner as yet untouched in the junction of some town streets; (iii) The greening management and maintenance technicians are unprofessional; (iv) The greening management is not in place; (v) There is management vacancy phenomenon in the management and maintenance of regional green space; (vi) The design and construction phase is flawed. Finally, based on the analysis of strengths and weaknesses of greening, we put forth the recommendations for the development of management and maintenance in urban green space.