bluuebunny/crossref_metadata_2025 huggingface dataset:
An Agent-Based Simulation of Deep Foundation Pit Emergency Evacuation Modeling in the Presence of Collapse Disaster
Authors: Yang Weilong , Hu Yue , Hu Cong , Yang Mei
Published: November 2018

With the gradual expansion of high buildings and underground spaces, deep foundation pits have been widely used in these engineering projects, but if they are not well-designed, safety problems occur. Proper deep foundation pit design requires proper exit distribution. However, calculating an adequate number of exit distributions for evaluation is difficult due to the numerous influential factors existing in the deep foundation pit environment. To this end, this paper presents a prototype of a decision-making system that uses agent-based modeling to simulate deep foundation pit evacuation in the presence of collapse disaster. By modeling the collapse occurrence process and agent escape process, an agent-based evacuation model is built, and a modified simulation-based particle swarm optimization algorithm is used to solve the optimization problem of exit distribution. Extensive experiments are conducted to verify the system, and the results show that the system provides a feasible framework for deep foundation pit evacuation.
A Reweighted Symmetric Smoothed Function Approximating L0-Norm Regularized Sparse Reconstruction Method
Authors: Xiang Jianhong , Yue Huihui , Yin Xiangjun , Ruan Guoqing
Published: November 2018

Sparse-signal recovery in noisy conditions is a problem that can be solved with current compressive-sensing (CS) technology. Although current algorithms based on L 1 regularization can solve this problem, the L 1 regularization mechanism cannot promote signal sparsity under noisy conditions, resulting in low recovery accuracy. Based on this, we propose a regularized reweighted composite trigonometric smoothed L 0 -norm minimization (RRCTSL0) algorithm in this paper. The main contributions of this paper are as follows: (1) a new smoothed symmetric composite trigonometric (CT) function is proposed to fit the L 0 -norm; (2) a new reweighted function is proposed; and (3) a new L 0 regularization objective function framework is constructed based on the idea of T i k h o n o v regularization. In the new objective function framework, Contributions (1) and (2) are combined as sparsity regularization terms, and errors as deviation terms. Furthermore, the conjugate-gradient (CG) method is used to optimize the objective function, so as to achieve accurate recovery of sparse signal and image under noisy conditions. The numerical experiments on both the simulated and real data verify that the proposed algorithm is superior to other state-of-the-art algorithms, and achieves advanced performance under noisy conditions.
Understanding User Behavioral Intention to Adopt a Search Engine that Promotes Sustainable Water Management
Authors: Reyes-Menendez Ana , Saura Jose Ramon , Palos-Sanchez Pedro R. , Alvarez-Garcia Jose
Published: November 2018

An increase in users’ online searches, the social concern for an efficient management of resources such as water, and the appearance of more and more digital platforms for sustainable purposes to conduct online searches lead us to reflect more on the users’ behavioral intention with respect to search engines that support sustainable projects like water management projects. Another issue to consider is the factors that determine the adoption of such search engines. In the present study, we aim to identify the factors that determine the intention to adopt a search engine, such as Lilo, that favors sustainable water management. To this end, a model based on the Theory of Planned Behavior (TPB) is proposed. The methodology used is the Structural Equation Modeling (SEM) analysis with the Analysis of Moment Structures (AMOS). The results demonstrate that individuals who intend to use a search engine are influenced by hedonic motivations, which drive their feeling of contentment with the search. Similarly, the success of search engines is found to be closely related to the ability a search engine grants to its users to generate a social or environmental impact, rather than users’ trust in what they do or in their results. However, according to our results, habit is also an important factor that has both a direct and an indirect impact on users’ behavioral intention to adopt different search engines.
Combining an Extended SMAA-2 Method with Integer Linear Programming for Task Assignment of Multi-UCAV under Multiple Uncertainties
Authors: Wang Jun , Luo Pengcheng , Hu Xinwu , Zhang Xiaonan
Published: November 2018

Uncertainty should be taken into account when establishing multiobjective task assignment models for multiple unmanned combat aerial vehicles (UCAVs) due to errors in the target information acquired by sensors, implicit preferences of the commander for operational objectives, and partially known weights of sensors. In this paper, we extend the stochastic multicriteria acceptability analysis-2 (SMAA-2) method and combine it with integer linear programming to achieve multiobjective task assignment for multi-UCAV under multiple uncertainties. We first represent the uncertain target information as normal distribution interval numbers so that the values of criteria (operational objectives) concerned can be computed based on the weighted arithmetic averaging operator. Thus, we obtain multiple criteria value matrices for each UCAV. Then, we propose a novel aggregation method to generate the final criteria value matrix based on which the holistic acceptability indices are computed by the extended SMAA-2 method. On this basis, we convert the task assignment model with uncertain parameters into an integer linear programming model without uncertainty so as to implement task assignment using the integer linear programming method. Finally, we conduct a case study and demonstrate the feasibility of the proposed method in solving the multiobjective task assignment problem multi-UCAV under multiple uncertainties.
Some Picture Fuzzy Dombi Heronian Mean Operators with Their Application to Multi-Attribute Decision-Making
Authors: Zhang Hongran , Zhang Runtong , Huang Huiqun , Wang Jun
Published: November 2018

As an extension of the intuitionistic fuzzy set (IFS), the recently proposed picture fuzzy set (PFS) is more suitable to describe decision-makers’ evaluation information in decision-making problems. Picture fuzzy aggregation operators are of high importance in multi-attribute decision-making (MADM) within a picture fuzzy decision-making environment. Hence, in this paper our main work is to introduce novel picture fuzzy aggregation operators. Firstly, we propose new picture fuzzy operational rules based on Dombi t-conorm and t-norm (DTT). Secondly, considering the existence of a broad and widespread correlation between attributes, we use Heronian mean (HM) information aggregation technology to fuse picture fuzzy numbers (PFNs) and propose new picture fuzzy aggregation operators. The proposed operators not only fuse individual attribute values, but also have a good ability to model the widespread correlation among attributes, making them more suitable for effectively solving increasingly complicated MADM problems. Hence, we introduce a new algorithm to handle MADM based on the proposed operators. Finally, we apply the newly developed method and algorithm in a supplier selection issue. The main novelties of this work are three-fold. Firstly, new operational laws for PFSs are proposed. Secondly, novel picture fuzzy aggregation operators are developed. Thirdly, a new approach for picture fuzzy MADM is proposed.
The Rise of Artificial Intelligence under the Lens of Sustainability
Authors: Khakurel Jayden , Penzenstadler Birgit , Porras Jari , Knutas Antti , Zhang Wenlu
Published: November 2018

Since the 1950s, artificial intelligence (AI) has been a recurring topic in research. However, this field has only recently gained significant momentum because of the advances in technology and algorithms, along with new AI techniques such as machine learning methods for structured data, modern deep learning, and natural language processing for unstructured data. Although companies are eager to join the fray of this new AI trend and take advantage of its potential benefits, it is unclear what implications AI will have on society now and in the long term. Using the five dimensions of sustainability to structure the analysis, we explore the impacts of AI on several domains. We find that there is a significant impact on all five dimensions, with positive and negative impacts, and that value, collaboration, sharing responsibilities; ethics will play a vital role in any future sustainable development of AI in society. Our exploration provides a foundation for in-depth discussions and future research collaborations.
Extraction of Structural and Semantic Data from 2D Floor Plans for Interactive and Immersive VR Real Estate Exploration
Authors: Gerstweiler Georg , Furlan Lukas , Timofeev Mikhail , Kaufmann Hannes
Published: November 2018

Three-dimensional reconstructions of indoor environments are useful in various augmented and virtual scenarios. Creating a realistic virtual apartment in 3D manually does not only take time, but also needs skilled people for implementation. Analyzing a floor plan is a complicated task. Due to the lack of engineering standards in creating these drawings, they can have multiple different appearances for the same building. This paper proposes multiple models and heuristics which enable fully automated 3D reconstructions out of only a 2D floor plan. Our study focuses on floor plan analysis and definition of special requirements for a 3D building model used in a Virtual Reality (VR) setup. The proposed method automatically analyzes floor plans with a pattern recognition approach, thereby extracting accurate metric information about important components of the building. An algorithm for mesh generation and extracting semantic information such as apartment separation and room type estimation is presented. A novel method for VR interaction with interior design completes the framework. The result of the presented system is intended to be used for presenting a large number of apartments to customers. It can also be used as a base for purposes such as furnishing apartments, realistic occlusions for AR (Augmented Reality) applications such as indoor navigation or analyzing purposes. Finally, a technical evaluation and an interactive user study prove the advantages of the presented system.
Heavy Metal Mixture Exposure and Effects in Developing Nations: An Update
Authors: Anyanwu Brilliance Onyinyechi , Ezejiofor Anthonet Ndidiamaka , Igweze Zelinjo Nkeiruka , Orisakwe Orish Ebere
Published: November 2018

The drive for development and modernization has come at great cost. Various human activities in developed and developing countries, particularly in sub-Saharan Africa (SSA) have given rise to environmental safety concerns. Increased artisanal mining activities, illegal refining, use of leaded petrol, airborne dust, arbitrary discarding and burning of toxic waste, absorption of production industries in inhabited areas, inadequate environmental legislation, and weak implementation of policies, have given rise to the incomparable contamination and pollution associated with heavy metals in recent decades. This review evaluates the public health effects of heavy metals and their mixtures in SSA. This shows the extent and size of the problem posed by exposure to heavy metal mixtures in regard to public health.
Innovative Immunization Strategies for Antivenom Development
Authors: Bermúdez-Méndez Erick , Fuglsang-Madsen Albert , Føns Sofie , Lomonte Bruno , Gutiérrez José María , Laustsen Andreas Hougaard
Published: November 2018

Snakes, scorpions, and spiders are venomous animals that pose a threat to human health, and severe envenomings from the bites or stings of these animals must be treated with antivenom. Current antivenoms are based on plasma-derived immunoglobulins or immunoglobulin fragments from hyper-immunized animals. Although these medicines have been life-saving for more than 120 years, opportunities to improve envenoming therapy exist. In the later decades, new biotechnological tools have been applied with the aim of improving the efficacy, safety, and affordability of antivenoms. Within the avenues explored, novel immunization strategies using synthetic peptide epitopes, recombinant toxins (or toxoids), or DNA strings as immunogens have demonstrated potential for generating antivenoms with high therapeutic antibody titers and broad neutralizing capacity. Furthermore, these approaches circumvent the need for venom in the production process of antivenoms, thereby limiting some of the complications associated with animal captivity and venom collection. Finally, an important benefit of innovative immunization approaches is that they are often compatible with existing antivenom manufacturing setups. In this review, we compile all reported studies examining venom-independent innovative immunization strategies for antivenom development. In addition, a brief description of toxin families of medical relevance found in snake, scorpion, and spider venoms is presented, as well as how biochemical, bioinformatic, and omics tools could aid the development of next-generation antivenoms.
Potential Impact of Climate Change on Schistosomiasis: A Global Assessment Attempt
Authors: Yang Guo-Jing , Bergquist Robert
Published: November 2018

Based on an ensemble of global circulation models (GCMs), four representative concentration pathways (RCPs) and several ongoing and planned Coupled Model Intercomparison Projects (CMIPs), the Intergovernmental Panel on Climate Change (IPCC) predicts that global, average temperatures will increase by at least 1.5 °C in the near future and more by the end of the century if greenhouse gases (GHGs) emissions are not genuinely tempered. While the RCPs are indicative of various amounts of GHGs in the atmosphere the CMIPs are designed to improve the workings of the GCMs. We chose RCP4.5 which represented a medium GHG emission increase and CMIP5, the most recently completed CMIP phase. Combining this meteorological model with a biological counterpart model accounted for replication and survival of the snail intermediate host as well as maturation of the parasite stage inside the snail at different ambient temperatures. The potential geographical distribution of the three main schistosome species: Schistosoma japonicum, S. mansoni and S. haematobium was investigated with reference to their different transmission capabilities at the monthly mean temperature, the maximum temperature of the warmest month(s) and the minimum temperature of the coldest month(s). The set of six maps representing the predicted situations in 2021–2050 and 2071–2100 for each species mainly showed increased transmission areas for all three species but they also left room for potential shrinkages in certain areas.
Mitochondrial-Directed Antioxidant Reduces Microglial-Induced Inflammation in Murine In Vitro Model of TC-83 Infection
Authors: Keck Forrest , Khan Daud , Roberts Brian , Agrawal Nitin , Bhalla Nishank , Narayanan Aarthi
Published: November 2018

Venezuelan equine encephalitis virus (VEEV) is an arbovirus that is associated with robust inflammation that contributes to neurodegenerative phenotypes. In addition to triggering central nervous system (CNS) inflammation, VEEV will also induce mitochondrial dysfunction, resulting in increased cellular apoptosis. In this study, we utilize the TC-83 strain of VEEV to determine the role of mitochondrial oxidative stress in mediating inflammation elicited by murine brain microglial cells. Using an in vitro model, we show that murine microglia are susceptible to TC-83 infection, and that these cells undergo mitochondrial stress as the result of infection. We also indicate that bystander microglia contribute more significantly to the overall inflammatory load than directly infected microglia. Use of a mitochondrial targeted antioxidant, mitoquinone mesylate, greatly reduced the pro-inflammatory cytokines released by both direct infected and bystander microglia. Our data suggest that release of interleukin-1β, a key instigator of neuroinflammation during VEEV infection, may be the direct result of accumulating mitochondrial stress. This data improves our understanding inflammation elicited by murine microglia and will aid in the development of more accurate in vitro and in vivo murine model of VEEV-induced neuroinflammation.
Transcriptomics Reveal Antiviral Gene Induction in the Egyptian Rousette Bat Is Antagonized In Vitro by Marburg Virus Infection
Authors: Arnold Catherine E. , Guito Jonathan C. , Altamura Louis A. , Lovett Sean P. , Nagle Elyse R. , Palacios Gustavo F. , Sanchez-Lockhart Mariano , Towner Jonathan S.
Published: November 2018

The Egyptian rousette bat (ERB) is the only known Marburg virus (MARV) reservoir host. ERBs develop a productive MARV infection with low viremia and shedding but no overt disease, suggesting this virus is efficiently controlled by ERB antiviral responses. This dynamic would contrast with humans, where MARV-mediated interferon (IFN) antagonism early in infection is thought to contribute to the severe, often fatal disease. The newly-annotated ERB genome and transcriptome have now enabled us to use a custom-designed NanoString nCounter ERB CodeSet in conjunction with RNA-seq to investigate responses in a MARV-infected ERB cell line. Both transcriptomic platforms correlated well and showed that MARV inhibited the antiviral program in ERB cells, while an IFN antagonism-impaired MARV was less efficient at suppressing the response gene induction, phenotypes previously reported for primate cells. Interestingly, and despite the expansion of IFN loci in the ERB genome, neither MARV showed specific induction of almost any IFN gene. However, we detected an upregulation of putative, unannotated ERB antiviral paralogs, as well as an elevated basal expression in uninfected ERB cells of key antiviral genes.
Physiological and Dry Matter Characteristics of Spring Maize in Northeast China under Drought Stress
Authors: Jiang Peng , Cai Fu , Zhao Zi-Qi , Meng Ying , Gao Ling-Yun , Zhao Tian-Hong
Published: November 2018

This paper examined impacts of drought on both physiological and dry matter characteristics of spring maize grown in Liaoning, China in 2016. We compared responses of dry matters of various parts, yield components, leaf photosynthesis, and transpiration to four drought levels: RD (no drought treatment), D1 (drought treatment between the 38th and 65th day after sowing), D2 (drought treatment between the 38th and 79th day after sowing), and D3 (drought treatment between the 53rd and 93rd day after sowing). Results indicate that the long-term drought in either jointing period or tasseling period had a severer impact on the dry matters and yield components than the short-term drought in jointing period. Moreover, the dry matters and the corresponding partitioning coefficients of different parts were distinct. The yield reduction was caused by the decreases of ear length and bald tip ratio during the short-term drought at jointing period, while it was caused by the reductions of ear length, ear diameter, and grain number per spike during the long-term drought in jointing and tasseling periods. Responses of leaf photosynthesis and transpiration to drought were lagging, but reactions of tasseling drought were faster. Leaf photosynthesis and transpiration after a short-term drought in jointing period could recover to an average level but that after the long-term drought in either jointing or tasseling period could not, after irrigation.
Liquid Sloshing Damping in an Accelerated Tank Using a Novel Slot-Baffle Design
Authors: Demirel Ender , Aral Mustafa M.
Published: November 2018

A slot-baffle design used in water treatment tanks previously developed by the authors is used to suppress sloshing effects in an accelerated tank. This new application is another example of the versatility of the slot-baffle design in inducing turbulence in fluid flow systems, which has numerous uses in engineering applications. Large amplitude surface waves in a harmonically excited tank are simulated using a second-order accurate numerical model in OpenFOAM. The verification of the numerical model is performed by comparing the numerical results with existing laboratory measurements, which show a favorable agreement. Various slot configurations are studied in order to evaluate the damping performance during the external excitation of the tank. It is shown that the present design shows an effective dissipation performance in a broad range of oscillation frequencies, while 88% of the internal kinetic energy of the liquid is dissipated over thirty oscillation periods for the resonance case.
Adaptive Detection Method for Organic Contamination Events in Water Distribution Systems Using the UV-Vis Spectrum Based on Semi-Supervised Learning
Authors: Yu Qiaojun , Yin Hang , Wang Ke , Dong Hui , Hou Dibo
Published: November 2018

A method that uses the ultraviolet-visible (UV-Vis) spectrum to detect organic contamination events in water distribution systems exhibits the advantages of rapid detection, low cost, and no need for reagents. The speed, accuracy, and comprehensive analysis of such a method meet the requirements for online water quality monitoring. However, the UV-Vis spectrum is easily disturbed by environmental factors that cause fluctuations of the spectrum and result in false alarms. This study proposes an adaptive method for detecting organic contamination events in water distribution systems that uses the UV-Vis spectrum based on a semi-supervised learning model. This method modifies the baseline using dynamic orthogonal projection correction and adjusts the support vector regression model in real time. Thus, an adaptive online anomaly detection model that maximizes the use of unlabeled data is obtained. Experimental results demonstrate that the proposed method is adaptive to baseline drift and exhibits good performance in detecting organic contamination events in water distribution systems.
Laboratory Efficacy and Disinfection by-Product Formation of a Coagulant/Disinfectant Tablet for Point-of-Use Water Treatment
Authors: Légaré-Julien Félix , Lemay Olivier , Vallée-Godbout Ulysse , Bouchard Christian , Dorea Caetano C.
Published: November 2018

Coagulant/disinfection products (CDPs) are a point-of-use (POU) water treatment technique that can improve microbial quality, reduce turbidity, and produce a free chlorine residual (FCR), serving as a potentially effective option for decentralized water treatment in a variety of contexts, including humanitarian emergencies. A novel CDP with a sodium dichloroisocyanurate-based disinfectant was evaluated with regard to its laboratory water treatment efficacy and generation of disinfection byproducts (DBPs). The CDP water treatment performance was assessed relative to bacteriological (E. coli) humanitarian water quality objectives, World Health Organization recommendations for evaluating POU water treatment options, and available DBP regulations and guidelines. At least 4 log10 E. coli reductions, for a “highly protective” status with regard to bacterial reductions, were attained in the tested conditions. Treated waters were consistently below 10 MPN/100 mL with regard to E. coli concentrations, with the majority of samples showing no detectable E. coli. For most conditions, target FCR values were not attained. Treated water turbidity levels were mostly between 5 NTU and 10 NTU. DBP levels were below the regulatory and health-based targets for both families of DBPs studied. This study has served to identify the performance envelopes of the CDP tested under challenging conditions.
Decomposition of Water Level Time Series of a Tidal River into Tide, Wave and Rainfall-Runoff Components
Authors: Lee Myungjin , You Younghoon , Kim Soojun , Kim Kyung Tak , Kim Hung Soo
Published: November 2018

The water-level time series of a tidal river is influenced by various factors and has a complex structure, which limits its use as hydrological forecast data. This study proposes a methodology for decomposing the water-level time series of a tidal river into various components that influence the water level. To this end, the tide, wave, rainfall-induced runoff and noise components were selected as the main components that affect the water-level time series. The tide component and the wave component were first separated through wavelet analysis and curve fitting and then they were removed from the water-level data. A high-pass filter was then applied to the resulting time series to separate the rainfall-induced runoff component and the noise component. These methods made it possible to determine the rate of influence that each component has on the water level of a tidal river. The results could be used as a basis for calibrating a rainfall-runoff model and issuing flood forecasts and warnings for a tidal river.
Influences on Water Quality and Abundance of Cladophora, a Shore-Fouling Green Algae, over Urban Shoreline in Lake Ontario
Authors: Howell E. Todd
Published: November 2018

Urban centers border western Lake Ontario, the terminus of the Laurentian Great Lakes, impacting water quality on the shores of this oligotrophic lake. The green algae Cladophora proliferates on the shallow lakebed and fouls the shoreline, presenting an eutrophication concern. The conditions over a typical urbanized shoreline were studied to assess linkages between Cladophora and area nutrient sources. The most pervasive of the mixing areas of varying extent identified using field sensor measurements was associated with the discharge of treated sewage from a Water Pollution Control Plant (WPCP). Phosphorus and nitrogen were enriched at times near the WPCP diffuser and also in shallow water along the shoreline. Dissolved nutrients were also measured directly above the lakebed in close proximity to Cladophora. Dissolved phosphorus and inorganic nitrogen were higher in proximity to the WPCP diffuser at times, however, spatial patterns were not as clearly aligned with external inputs as the patterns of enrichment in the water column. Biomass distribution of Cladophora was unrelated to nutrient levels in the water column or at the lakebed. Yet, concentrations of phosphorus in Cladophora, an indicator of nutrient sufficiency, were higher near the WPCP diffuser. This disparity, while possibly an artifact of variable loss rates of biomass among locations, may in part stem from variable water clarity among areas. Abundant dreissenid mussels also potentially obscure the effects of nutrient loading on algal biomass if the sequestering of phosphorus from offshore plankton, suggested by periods of onshore circulation, approaches the extent of external loading. Further study of phosphorus flux at the lakebed is required to establish clear linkages between external nutrient loading and algal growth in order to manage the proliferation of Cladophora over urban coastline.
Synthetic Hydrographs Generation Downstream of a River Junction Using a Copula Approach for Hydrological Risk Assessment in Large Dams
Authors: Aranda Jose Angel , García-Bartual Rafael
Published: November 2018

Peak flows values (Q) and hydrograph volumes (V) are obtained from a selected family of historical flood events (period 1957–2017), for two neighboring mountain catchments located in the Ebro river basin, Spain: rivers Ésera and Isábena. Barasona dam is located downstream of the river junction. The peaks over threshold (POT) method is used for a univariate frequency analysis performed for both variables, Q and V, comparing several suitable distribution functions. Extreme value copulas families have been applied to model the bivariate distribution (Q, V) for each of the rivers. Several goodness-of-fit tests were used to assess the applicability of the selected copulas. A similar copula approach was carried out to model the dependence between peak flows of both rivers. Based on the above-mentioned statistical analysis, a Monte Carlo simulation of synthetic design flood hydrographs (DFH) downstream of the river junction is performed. A gamma-type theoretical pattern is assumed for partial hydrographs. The resulting synthetic hydrographs at the Barasona reservoir are finally obtained accounting for flow peak time lag, also described in statistical terms. A 50,000 hydrographs ensemble was generated, preserving statistical properties of marginal distributions as well as statistical dependence between variables. The proposed method provides an efficient and practical modeling framework for the hydrological risk assessment of the dam, improving the basis for the optimal management of such infrastructure.
Stern Twin-Propeller Effects on Harbor Infrastructures. Experimental Analysis
Authors: Mujal-Colilles Anna , Castells Marcel·la , Llull Toni , Gironella Xavi , Martínez de Osés Xavier
Published: November 2018

The growth of marine traffic in harbors, and the subsequent increase in vessel and propulsion system sizes, produces three linked problems at the harbor basin area: (i) higher erosion rates damaging docking structures; (ii) sedimentation areas reducing the total depth; (iii) resuspension of contaminated materials deposited at the seabed. The published literature demonstrates that there are no formulations for twin stern propellers to compute the maximum scouring depth. Another important limitation is the fact that the formulations proposed only use one type of maneuvering during the experimental campaign, assuming that vessels are constantly being undocked. Trying to reproduce the real arrival and departure maneuvers, 24 different tests were conducted at an experimental laboratory in a medium-scale water tank using a twin propeller model to estimate the consequences and the maximum scouring depth produced by stern propellers during the backward/docking and forward/undocking scenarios. Results confirm that the combination of backward and forward scenario differs substantially from the experiments performed so far in the literature using only an accumulative forward scenario, yielding deeper scouring holes at the harbor basin area. The results presented in this paper can be used as guidelines to estimate the effects of regular vessels at their particular docking location.
A Comprehensive Method of Calculating Maximum Bridge Scour Depth
Authors: Saha Rupayan , Lee Seung Oh , Hong Seung Ho
Published: November 2018

Recently, the issues of scour around a bridge have become prominent because of the recurrent occurrence of extreme weather events. Thus, a bridge must be designed with the appropriate protection measures to prevent failure due to scour for the high flows to which it may be subjected during such extreme weather events. However, the current scour depth estimation by several recommended equations shows inaccurate results in high flow. One possible reason is that the current scour equations are based on experiments using free-surface flow even though extreme flood events can cause bridge overtopping flow in combination with submerged orifice flow. Another possible reason is that the current practice for the maximum scour depth ignores the interaction between different types of scour, local and contraction scour, when in fact these processes occur simultaneously. In this paper, laboratory experiments were carried out in a compound shape channel using a scaled down bridge model under different flow conditions (free, submerged orifice, and overtopping flow). Based on the findings from laboratory experiments coupled with widely used empirical scour estimation methods, a comprehensive way of predicting maximum scour depth is suggested which overcomes the problem regarding separate estimation of different scour depths and the interaction of different scour components. Furthermore, the effect of the existence of a pier bent (located close to the abutment) on the maximum scour depth was also investigated during the analysis. The results show that the location of maximum scour depth is independent of the presence of the pier bent but the amount of the maximum scour depth is relatively higher due to the discharge redistribution when the pier bent is absent rather than present.
Fingerprinting Suspended Sediment Sources in an Urbanized Watershed
Authors: Malhotra Kritika , Lamba Jasmeet , Srivastava Puneet , Shepherd Stephanie
Published: November 2018

The elevated supply of fine-grained sediment to a river system negatively impacts the water quality and ecosystem health. Therefore, quantification of the relative contribution from different sources to in-stream sediment is of major interest to target sediment mitigation best management practices (BMPs). The objective of this study was to determine the relative contribution from different sources of suspended sediment in an urbanized watershed (31 km2) located in the eastern part of Alabama, USA. Estimates of relative contributions from individual source types were assessed for two different particle size fractions, 63–212 μm (fine sand) and <63 μm (silt and clay). Results of this study indicate that the construction sites were the dominant source of suspended sediment in this watershed. The average annual subwatershed-level surface runoff determined using the Soil and Water Assessment Tool (SWAT) model varied from 2.3 to 11,980 mm ha−1 year−1. Areas that generate high surface runoff have the potential to contribute disproportionately high amounts of sediment to streams and therefore should be targeted for BMPs. The results of this study show that it is important to consider spatial and temporal variability in suspended sediment sources in order to develop and target sediment control management strategies. The sources of suspended sediment and sediment deposited on the stream bed might not necessarily be the same. Therefore, sampling both suspended sediment and stream bed sediment will improve our knowledge of watershed-level sediment transport processes.
An Integrated Analysis of the Eutrophication Process in the Enxoé Reservoir within the DPSIR Framework
Authors: Ramos Tiago B. , Darouich Hanaa , Gonçalves Maria C. , Brito David , Castelo Branco Maria A. , Martins José C. , Fernandes Manuel L. , Pires Fernando P. , Morais Manuela , Neves Ramiro
Published: November 2018

The Enxoé reservoir in southern Portugal has been exhibiting the highest trophic state in the country since its early years of operation. The problem has attracted water managers’ and researchers’ attention as the reservoir is the water supply for two municipalities. Extensive research was thus conducted over the last few years, including field monitoring and modelling at the plot, catchment, and reservoir scales. This study now frames all partial findings within the Driver-Pressure-State-Impact-Response (DPSIR) framework to better understand the eutrophication process in the Enxoé reservoir. Agriculture and grazing were found to have a reduced role in the eutrophication of the reservoir, with annual sediment and nutrient loads being comparably smaller or similar to those reported for other Mediterranean catchments. Flash floods were the main mechanism for transporting particle elements to the reservoir, being in some cases able to carry up three times the average annual load. However, the main eutrophication mechanisms in the reservoir were P release from deposited sediment under anoxic conditions and the process of internal recycling of organic matter and nutrients. Reducing the P load from the catchment and deposited sediment could lead to a mesotrophic state level in the reservoir. However, this level would only be sustainable by limiting the P internal load ability to reach the photic zone.
A Modified Empirical Retracker for Lake Level Estimation Using Cryosat-2 SARin Data
Authors: Xue Hui , Liao Jingjuan , Zhao Lifei
Published: November 2018

Satellite radar altimetry is an important technology for monitoring water levels, but issues related to waveform contamination restrict its use for rivers, narrow reservoirs, and small lakes. In this study, a novel and improved empirical retracker (ImpMWaPP) is presented that can derive stable inland lake levels from Cryosat-2 synthetic aperture radar interferometer (SARin) waveforms. The retracker can extract a robust reference level for each track to handle multi-peak waveforms. To validate the lake levels derived by ImpMWaPP, the in situ gauge data of seven lakes in the Tibetan Plateau are used. Additionally, five existing retrackers are compared to evaluate the performance of the proposed ImpMWaPP retracker. The results reveal that ImpMWaPP can efficiently process the multi-peak waveforms of the Cryosat-2 SARin mode. The root-mean-squared errors (RMSEs) obtained by ImpMWaPP for Qinghai Lake, Nam Co, Zhari Namco, Ngoring Lake, Longyangxia Reservoir, Bamco, and Dawa Co are 0.085 m, 0.093 m, 0.109 m, 0.159 m, 0.573 m, 0.087 m, and 0.122 m, respectively. ImpMWaPP obtains the lowest mean RMSE (0.175 m) over the seven lakes, indicating that it extracts lake levels well during icing and no-ice periods, and is more suitable for lakes frozen in winter.
Symétrie des polyèdres polychromatiques
Authors: Wittke O. , Garrido Julio
Published: November 2018

Déduction des symétries des polyèdres cristallographiques avec les faces colorées.

Leur nombre est de 211. On propose une notation simple de ces symétries et on déduit les caractéristiques des différentes formes cristallines de chacune d'elles.
Un objectif à axe optique incliné pour le microscope polarisant
Authors: Bordet Pierre
Published: November 2018

Un dispositif optique, ajouté à un objectif, permet d'incliner l'axe optique de celui-ci à 45°. L'ensemble ainsi constitué permet la détermination de l'uniaxie et de la biaxie des cristaux, la mesure de l'inclinaison de l'axe optique des cristaux uniaxes, la mesure de l'angle des axes optiques des cristaux biaxes, enfin, la mesure de la biréfringence des cristaux en grains.
Étude de la substitution du silicium dans quelques types d'orthosilicates
Authors: Durif-Varambon André
Published: November 2018

La première partie de ce travail est consacrée à l'étude cristallographique systématique de la substitution du silicium par le germanium dans trois classes d'orthosilicates :

la classe des silicates de formule SiO₄M (M = Zr, Th et U) représentée par les types de structure zircon et monazite,

la classe des silicates de formule SiO₄M₂ (M = Be, Zn, Co, Ni, Fe...) représentée par les types de structure olivine et phénacite,

la classe de l'eulytine (SiO₄)₃Bi₄.

L'étude montre que la règle dite de substitution «isomorphe » de Si par Ge est très souvent en défaut dans le cas des orthosilicates.

Dans le cas des orthosilicates SiO₄M la substitution conduit à des composés (GeO₄M) du type scheelite avec M = Zr, Ce, Th et U. Le dimorphisme d'un de ces composés (GeO₄Th) a permis d'observer la première transition scheelite-zircon.

Dans le cas des orthosilicates SiO₄M₂ la substitution conduit à des germanates GeO₄M₂ qui nous ont permis :

a) de préciser la nature des germanates spindles : on a affaire dans tous les cas à des spinelles normaux (M = Fe, Ni, Co et Mg) ;

b) d'identifier deux nouveaux germanates isomorphes de l' olivine (M = Ca et Mn).

Dans cette même classe nous avons étudié les transitions spinelle-olivine et spi-nelle-phénacite grâce à la préparation de germanates mixtes.

L'étude magnétique des solutions solides germanates spinelles -ferrites spinelles confirme les théories de L. Néel et permet de montrer que le germanium peut dans certaines conditions adopter un voisinage octaédrique d'oxygène.

Enfin la substitution du silicium par le germanium dans le cas de l'eulytine conduit à l'identification d'un germanate isomorphe du silicate.

La deuxième partie est consacrée à l'étude systématique de la substitution des groupements (SiO₄) par d'autres groupements (XO₄) également tétraédriques, dans deux classes d'orthosilicates :

a) la classe des zircons,

b ) la classe de l'eulytine.

Ici la substitution des groupements tétravalents (SiO₄) par des groupements (XO4) de valences diverses (X = Cr⁶⁺, S⁶⁺, P⁵⁺, As⁺...) conduit à un déséquilibre électrostatique qu'il faut compenser par une substitution plus ou moins totale des ions associés du silicate.

On décrit 9 composés nouveaux du type zircon et 14 composés du type eulytine.

On précise les conditions permettant d'effectuer ce genre de substitutions dans les orthosilicates.
L'assistance à la résolution de problème dans la supervision de processus
Authors: Bisseret André
Published: November 2018

Les tâches de supervision de processus sont actuellement transformées : dans de nombreux secteurs les superviseurs passent de la surveillance sur les grands tableaux de contrôle classiques à une surveillance par dialogue homme-ordinateur sur terminal.

Certes ce faisant, les présentations d'informations peuvent être améliorées et actuellement des travaux intéressants sont poursuivis dans ce sens. Mais en fait il devient possible d'aller plus loin que la simple présentation d'information vers la participation directe de l'ordinateur aux activités de décision même des superviseurs. Le concept de système expert pourrait s'avérer utile mais seulement pour les activités expertes.

Cet article insiste sur le problème de l'assistance aux superviseurs lors de leur activité (non experte) de résolution de problème lorsqu'ils sont confrontés à des situations anormales Imprévues.

La nécessité d'accélérer les recherches dans cette direction est soulignée en insistant sur l'importance d'une assistance à 1'"apprentissage par la découverte". Des résultats récents tant en psychologie cognitive qu'en intelligence artificielle sont suggérés comme exemples de voies de recherche possibles.
Raisonnement et ébauche de raisonnement
Authors: Coulon Daniel
Published: November 2018

Le thème de cette étude est de montrer que la compréhension d'une situation nécessite des raisonnements qui, pour être valides, peuvent s'avérer impossibles ou trop coûteux. Les causes de ce blocage sont bien souvent le manque de ressources, notamment l'absence de certaines informations de base et/ ou le manque de temps pour réfléchir à toutes les possibilités. Dans ce cas, on aimerait pouvoir approcher la solution par des voies détournées.

Ce que l'humain fait naturellement peut-il s'automatiser au moins partiellement ? Nous nous inspirons d'exemples de la vie courante pour poser la question et recenser d'autres procédés que la déduction rigoureuse. Nous nous limitons au raisonnement par analogie, sur lequel nous avons davantage travaillé, pour expliquer notre stratégie. Il s'agit d'utiliser la description de ces inférences approchées pour définir le raisonnement déductif rigoureux devant confirmer, en les précisant, ou bien infirmer les résultats obtenus.
Local vs. Distributed Coding
Authors: Thorpe Simon
Published: November 2018

The question of how information can be represented in networks of neurons is central to cognitive science - especially so now that some researchers are turning to connectionist models in an attempt to understand human cognition. A major distinction can be made between local coding schemes, in which each unit is assigned a particular meaning, and distributed coding, in which information is encoded by large numbers of units, each of which is involved in representing many different concepts. Many brain scientists dislike local coding schemes, but it is argued here that the arguments generally invoked against local coding are far from convincing. There are situations where it has been shown that the brain does use a form of distributed coding, often referred to as coarse coding, which is particularly useful for representing continuous variables during sensory and motor processing. However, it may be appropriate to think of the brain as a hybrid system, using more local codes for higher level representation. Such a view has the advantage of allowing more conventional symbol manipulation based artificial intelligence approaches to be integrated into a connectionist framework.
Une contribution de l'intelligence artificielle au dilemme : représentation locale / représentation distribuée
Authors: Grumbach Alain
Published: November 2018

Cette contribution propose d'étudier l'apport de l'Intelligence Artificielle à l'investigation de la structure neuronale, que l'on peut caricaturer par la question : est-il pertinent de parler d'un neurone associé au concept "grand-mère" ? Après un éclairage de la question, nous étudions différents types de représentations (locale, distribuée) et essayons d'expliciter leurs spécificités. Plutôt qu'une réponse, cette contribution propose une démarche permettant d'effectuer un pas vers celle-ci.
Modèles connexionnistes et représentations structurées
Authors: Visetti Yves-Marie
Published: November 2018

Cet article traite du problème de la représentation connexionniste des structures et des processus, dans la perspective d'une schématisation possible de certaines théories linguistiques. Une première partie définit le statut des modèles concernés. La seconde partie énonce le problème de la structure, et analyse les moyens techniques dont on dispose actuellement pour y répondre. Une approche générale du traitement des processus symboliques par le biais d'une syntaxe d'attracteurs est ensuite dégagée. Une troisième et dernière partie présente quelques remarques sur la portée du paradigme connexionniste dans le domaine linguistique, et au-delà dans la conception des systèmes symboliques.
Reasoning and Social Psychology : From Mental Logic To a Perspective Approach
Authors: Legrenzi Paolo , Sonino Legrenzi Maria
Published: November 2018

This paper discusses the insufficiency of approaches which consider reasoning processes in the light of logical models that neglect social context. Even when tasks are solved individually, the fact that subjects imagine the social context of the problem may be important. That is, they may imagine the goals of the promisor, promisee, and agent of the promise, when the promise, for example, is utilized as a rule in Wason's selection task. Theories such as that of Cosmides (1989), which explains content effects in terms of standard social contracts, do not seem to be sufficient ; they should be completed in order to explain differences like those obtained by Gigerenzer & Hug (1990) between what these authors call "unilateral" and "bilateral" cheating options. This work concludes with a general discussion of the relation between reasoning and social psychology.