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Urban flooding poses serious threats to human life. In China, many cities have recently experienced flooding during every rainy season. Several years ago, policies, scientific methods, and engineering measures were applied to address this systematic problem. However, flooding disasters remain frequent in urban areas in China. Therefore, this article discusses the human-earth relationship from a philosophical perspective to analyse the causes of urban water problems. This article mainly illustrates the value of the what-if analysis concept and how to use this concept to address urban flooding issues and improve the management of urban overland flow. However, the existing simulation models and software do not effectively support what-if analyses. In particular, most existing urban hydrological simulation models and software do not sufficiently consider the heterogeneity of geographical objects on urban surfaces and lack interactions to support what-if analyses. These limitations hinder effective implementation of what-if analysis. This article introduces three key technologies that allow an urban overland flow simulation system to effectively support what-if analyses: 1) urban spatial automatic discretization and topo-adjacency, which reflect the heterogeneity of an urban area; 2) hydrological models for the simulation of the hydrologicalprocesses of the main geographical objects in the urban area; and 3) key strategies for a visual analytic platform to support what-if analyses in well-perceived way. The experiment was conducted using a community in Chongqing as a case study. The results demonstrate that the designed key technologies and functions of the proposed system can support what-if analysis and that what-if analysis is an important and useful concept for urban water management.

In the collaborative mapping of disasters, response situations and decisions, it is important to support various emergency responders with a unified platform to help in decision making and coordinating emergency action. However, most existing symbol libraries focus primarily on representing disasters and related information. These libraries lack specific symbols to map response situations and emergency decisions. For representation of dynamic disasters and response factors, these symbols support rich interactive editing after the symbols are mapped. In addition, decision making and mapping of disasters and response situations typically involve different domains of expertise and different responsibilities of map makers. It is essential to construct a collaborative mapping engine that supports disaster and emergency mapping on a collaborative platform. However, most existing methods of collaboration cannot readily support collaboration on symbols containing complex data structures or accommodate rich interactive editing operations. This article proposes a collaborative mapping engine for dynamic disasters and emergency responses. To support collaborative mapping based on complex data structures and rich interactive map symbols, it proposes a method of mapping operation replication to implement collaboration. Additionally, strategies were designed to enhance the efficiency and stability of collaboration. Finally, an experiment was conducted using the Wenchuan earthquake as an example. The results reveal that the engine can contribute to improved mapping efficiency and management during emergencies.

This paper presents a universal fifth-order Stokes solution for steady water waves on the basis of potential theory. It uses a global perturbation parameter, considers a depth uniform current, and thus admits the flexibilities on the definition of the perturbation parameter and on the determination of the wave celerity. The universal solution can be extended to that of Chappelear (1961), confirming the correctness for the universal theory. Furthermore, a particular fifth-order solution is obtained where the wave steepness is used as the perturbation parameter. The applicable range of this solution in shallow depth is analyzed. Comparisons with the Fourier approximated results and with the experimental measurements show that the solution is fairly suited to waves with the Ursell number not exceeding 46.7.

Fully transparent inverted quantum dot light-emitting diodes (QLEDs) were fabricated by incorporating a Ag-nanowire-based anode. Aluminum-doped zinc oxide (ZnO:Al, AZO) was inserted by atomic layer deposition and reduced the sheet resistance by promoting adhesion of Ag nanowires (AgNWs) film and increasing its chemical stability towards oxygen. The performance of the QLEDs was optimal when the thickness of AZO was 20 nm. The current efficiency of the fully transparent inverted QLEDs integrated with the AgNWs/AZO anode reached 15.33 cd A-1. The main peak wavelength and optical transmittance of the inverted QLEDs were 530 nm and 75.66%, respectively. This discovery is expected to provide a basic method for the production of flexible displays with full transparency by AgNWs-based electrodes.

It was practicable to remove hemangiomas at the labyrinth region and distal internal auditory canal with complete or serviceable hearing preservation by the transmastoid approach. The majority of cases where the nerve integrity was preserved achieved acceptable recovery of facial nerve function during the first few years according to our study. Long-term outcomes of nerve graft were acceptable, while short-term outcomes were unsatisfactory based on the literature.This study aimed to present our surgical experience of nine intratemporal facial nerve hemangiomas and provide a brief literature review.Clinical data for the cases were retrospectively analyzed. They were followed up for 5-59 months and related literature was reviewed.All of the hemangiomas were removed by the transmastoid approach, and only three cases developed mild conductive hearing loss. Nerve integrity was preserved for all cases. In all, 66.7% of patients maintained or recovered to grade III or better, and one patient with grade VI recovered to grade V during the average follow-up period of 2 years. In the literature the majority of grafted patients recovered to an acceptable level 5 years later, although recovery was usually poor during the first year.

The first presentation of intratemporal facial neurofibromas was variable, with facial palsy most common. The tumors often involve two or more segments of facial nerve. Outcomes of the tumors were closely related to nerve integrity, preoperative facial nerve function level, and follow-up period.The aim of this study was to present surgical experience of 11 cases with intratemporal facial neurofibroma.Clinical data of the 11 cases with the tumors was retrospectively collected and analyzed. They were followed up for 37.9 ± 1.7 months, range 13-59 months, except for one case that was only followed up for 5 months and was excluded from the analysis of outcomes.Facial palsy was the first presentation in 10 cases, with repetitive facial palsy and vertigo in 1 case; 6 cases (54.5%) were insidious and 5 (45.5%) were sudden in terms of onset. Ear pain around the onset of facial palsy was found in four cases (36.4%). The tumor involved more than one segment in six cases. Among the non-grafted cases one patient with grade V facial nerve function recovered to grade III and another patient with grade VI facial nerve function recovered to grade IV, whereas only one case with grade VI recovered to grade IV among the grafted cases.

Conclusions: A lateral hump anomaly of the pyramid segment of the facial nerve deserves special attention during otologic surgery. Coronary high-resolution CT (HRCT) reconstruction of temporal bone was highly valuable in preoperative detection of the anomaly. Objective: This study aimed to investigate lateral hump anomaly of the pyramid segment of the facial nerve in adult patients and assess the value of coronary HRCT reconstruction of the temporal bone in preoperative detection of the anomaly. Methods: We carried out a prospective study in 439 Han Chinese adults who underwent unilateral facial nerve decompression due to Bell's palsy in our department between April 2005 and October 2012, focusing on lateral hump anomaly of the pyramid segment of the facial nerve, detection sensitivity, and accuracy of coronary HRCT reconstruction of the temporal bone. Results: Lateral hump anomaly of the pyramid segment was observed in 21 cases (4.83%) undergoing surgery. The detection sensitivity and accuracy o...

Subtotal facial nerve decompression seems effective to prevent further episodes of facial palsy and promote facial nerve recovery for recurrent facial palsy in Melkersson Rosenthal syndrome (MRS). The main inflammatory sites of recurrent facial palsy in MRS may be the mastoid segment, tympanic segment, geniculate ganglion, and labyrinthine segment.To present our surgical experience in preventing further episodes of facial palsy and improving facial nerve recovery of patients with recurrent facial palsy in MRS.We performed transmastoid subtotal facial nerve decompression on eight patients with recurrent facial palsy in MRS. They were followed up for 3.3 years on average (range 2-5 years).There were no further attacks of facial palsy in any of the cases. Seven cases (87.5%) recovered to grade I or grade II, and three of eight cases (37.5%) recovered completely. We found obvious edema of the facial nerve at the mastoid segment in all cases, at the tympanic segment and geniculate ganglion in five cases (62.5%), and at the labyrinthine segment in only one case (12.5%).

This article describes systematic research on the tide dynamic system under the support of the Geographic Information System and ocean fluid dynamics model. Through the high-resolution numerical simulation, we found some previously unreported phenomena, such as a low tide amplitude zone of the M2 constituent near Zhoushan isles, a low tide amplitude zone of the K1 constituent near Taiwan island, and a circular flow point band. The results of this research also show that the formation of the tide system is affected by sea-bottom friction coefficient, topography under water, and shoreline morphology. The change of shoreline morphology and significant change of topography under water play important roles in the tide system. Under specified conditions on input tide waves, shoreline morphology has a dominant impact on the formation of the tide system. With the systematically reconstructed sea level and the coastal change of 30 periods since the Pleni Glacier, the evolution process of the tide system of the Eas...

Introduction of an effective wave elevation function, the simplest time-dependent hyperbolic mild-slope equation has been presented and an effective numerical model for the water wave propagation has been established combined with different boundary conditions in this paper. Through computing the effective wave elevation and transforming into the real transient wave motion, then related wave heights are computed. Because the truncation errors of the presented model only induced by the dissipation terms, but those of Lin’s model (2004) contributed by the convection terms, dissipation terms and source terms, the error analysis shows that calculation stability of this model is enhanced obviously compared with Lin’s one. The tests show that this model succeeds to the merit in Lin’s one and the computer program simpler, computational time shorter because of calculation stability enhanced efficiently and computer memory decreased obviously. The presented model has the capability of simulating exactly the location of transient wave front by the speed of wave propagation in the first test, which is important for the real-time prediction of the arrival time of water waves generated in the deep sea. The model is validated against experimental data for combined wave refraction and diffraction over submerged circular shoal on a flat bottom in the second test. Good agreements are gained. The model can be applied to the theory research and engineering applications about the wave propagation in the coastal waters.Copyright © 2007 by ASME

Previous studies pointed out that due to the acceleration or deceleration action of tide current, the flow structure deviates from traditional logarithmic law in estuary, coast or other near shore water. The tidal velocity distribution model was derived and compared with the traditional logarithmic model. It should be pointed out that the velocity data adopted have four layers within one meter above the bed, and the roughness length z0 is different in the two models even in the same velocity profile. Because the fluctuation of roughness length z0 is remarkable when determining by single velocity profile, some studies thought that the variation of roughness length was small between adjacent time when the change of topography was less obviously. Therefore, the measured data is divided into several sections by one day or a tidal cycle to fit the velocity profile of every section to obtain a roughness length z0 , i.e., the roughness length z0 varies only after a day or a tidal cycle. The purpose of the paper is to expand the log-linear model to full depth by adding the surface boundary condition ∂u∂zz=D = 0 (D is water depth) and to discuss the difference when 6 points (bottom layer, 0.2D, 0.4D, 0.6D, 0.8D, surface layer) velocity profile are fitted by logarithmic model, log-linear model, and extended log-linear model with the same roughness length z0 in different time section, respectively. The calculated friction velocity and friction coefficient and their correlation are discussed. The results show that the log-linear model and the log-linear extend model are closer to the measure velocity profile than that of the logarithmic model.Copyright © 2006 by ASME