Comparing different error structures in MixSIAR analysis using artificial mixtures from real sediment sources

2020 ◽  
Author(s):  
Luis Ovando-Fuentealba ◽  
Alex Taylor ◽  
Caroline Clason ◽  
Claudio Bravo-Linares ◽  
William Blake
Keyword(s):  
Internal Variability ◽  
Residual Error ◽  
Model Parameters ◽  
Sediment Sources ◽  
Model Framework ◽  
The Real ◽  
Fine Sediments ◽  
Multiplicative Error ◽  
Significant Difference ◽  
Artificial Mixtures

<p>Within a catchment context, statistical models are widely used to predict the load of pollutants (i.e. fine sediments, chemicals compounds) from potential sources around it, into a main channel (mixture). MixSIAR is a Bayesian mixing model framework that has been used in many environmental studies. As with other models, it presents some assumptions that might be assessed before its use. In this study, a set of artificial mixtures (from real sources) were created using four different catchment sediment sources (Channel Bank; Cultivated land; Pasture and Road Material). The material collected from each source was sieved (<63um) then analysed via WD-XRF for elemental composition. The data collected from this analysis was used to test and assess the main model parameters within an experimental context. A simple range test was performed to initially select tracers that were potentially good predictors. In the end, the model was structured with 43 tracers (elements) using the mean and standard deviation among 10 replicates. Furthermore, it was run using 10^6 iterations (length of the chain) and two different error structures to be compared (residual vs multiplicative error). The results demonstrated the accuracy of the MixSIAR approach to get the real composition in different mixture combinations using a large number of tracers, although in some mixtures a statistically different value was observed where the source term with highest internal variability was present in larger proportion (frequently when %CB >10%). The most precise and reliable results based on convergence were those using the “Residual error” structure, where the value of each mixture was closer to the real and model convergence was achieved more easily. On the other hand, “Multiplicative error” structure led to longer model run times (due to its complexity) and in most cases the model did not converge as for the “Residual error” structure when using the full set of tracers. To mitigate this problem, a posterior tracer selection based on diagnostic information was devised which made it  possible to increase dramatically the convergence of the predicted parameters without a significant difference in the result. Although the “Residual error” structure showed to be the most convenient for further analysis, the technique applied for “Multiplicative error” structure can be used as a potential solution to achieve model convergence while reducing model runtime.</p>

Personal Audio System: Hearing Symptoms, Habits, and Sound Pressure Levels Measured in Real Ear and a Manikin

2020 ◽  
Vol 63 (6) ◽  
pp. 2016-2026
Author(s):  
Tamara R. Almeida ◽  
Clayton H. Rocha ◽  
Camila M. Rabelo ◽  
Raquel F. Gomes ◽  
Ivone F. Neves-Lobo ◽  
...  
Keyword(s):  
Sound Pressure ◽  
Daily Basis ◽  
Cross Sectional Study ◽  
Normal Hearing ◽  
Chi Square ◽  
Cross Sectional ◽  
The Real ◽  
Significant Difference ◽  
Sound Pressure Levels ◽  
Audio System

Purpose The aims of this study were to characterize hearing symptoms, habits, and sound pressure levels (SPLs) of personal audio system (PAS) used by young adults; estimate the risk of developing hearing loss and assess whether instructions given to users led to behavioral changes; and propose recommendations for PAS users. Method A cross-sectional study was performed in 50 subjects with normal hearing. Procedures included questionnaire and measurement of PAS SPLs (real ear and manikin) through the users' own headphones and devices while they listened to four songs. After 1 year, 30 subjects answered questions about their usage habits. For the statistical analysis, one-way analysis of variance, Tukey's post hoc test, Lin and Spearman coefficients, the chi-square test, and logistic regression were used. Results Most subjects listened to music every day, usually in noisy environments. Sixty percent of the subjects reported hearing symptoms after using a PAS. Substantial variability in the equivalent music listening level (Leq) was noted ( M = 84.7 dBA; min = 65.1 dBA, max = 97.5 dBA). A significant difference was found only in the 4-kHz band when comparing the real-ear and manikin techniques. Based on the Leq, 38% of the individuals exceeded the maximum daily time allowance. Comparison of the subjects according to the maximum allowed daily exposure time revealed a higher number of hearing complaints from people with greater exposure. After 1 year, 43% of the subjects reduced their usage time, and 70% reduced the volume. A volume not exceeding 80% was recommended, and at this volume, the maximum usage time should be 160 min. Conclusions The habit of listening to music at high intensities on a daily basis seems to cause hearing symptoms, even in individuals with normal hearing. The real-ear and manikin techniques produced similar results. Providing instructions on this topic combined with measuring PAS SPLs may be an appropriate strategy for raising the awareness of people who are at risk. Supplemental Material https://doi.org/10.23641/asha.12431435

scholarly journals Parameter Optimization for Real-World ENSO Forecast in an Intermediate Coupled Model

2019 ◽  
Vol 147 (5) ◽  
pp. 1429-1445 ◽  
Author(s):  
Yuchu Zhao ◽  
Zhengyu Liu ◽  
Fei Zheng ◽  
Yishuai Jin
Keyword(s):  
Data Assimilation ◽  
Parameter Optimization ◽  
Real World ◽  
Climate Models ◽  
Coupled Model ◽  
Prediction Skill ◽  
Model Parameters ◽  
Real World Data ◽  
The Real ◽  
Advection Term

Abstract We performed parameter estimation in the Zebiak–Cane model for the real-world scenario using the approach of ensemble Kalman filter (EnKF) data assimilation and the observational data of sea surface temperature and wind stress analyses. With real-world data assimilation in the coupled model, our study shows that model parameters converge toward stable values. Furthermore, the new parameters improve the real-world ENSO prediction skill, with the skill improved most by the parameter of the highest climate sensitivity (gam2), which controls the strength of anomalous upwelling advection term in the SST equation. The improved prediction skill is found to be contributed mainly by the improvement in the model dynamics, and second by the improvement in the initial field. Finally, geographic-dependent parameter optimization further improves the prediction skill across all the regions. Our study suggests that parameter optimization using ensemble data assimilation may provide an effective strategy to improve climate models and their real-world climate predictions in the future.

scholarly journals Antifungal Activity of Propyl Disulfide from Neem (Azadirachta indica) in Vapor and Agar Diffusion Assays against Anthracnose Pathogens (Colletotrichum gloeosporioides and Colletotrichum acutatum) in Mango Fruit

2021 ◽  
Vol 9 (4) ◽  
pp. 839
Author(s):  
Muhammad Rafiullah Khan ◽  
Vanee Chonhenchob ◽  
Chongxing Huang ◽  
Panitee Suwanamornlert
Keyword(s):  
Antifungal Activity ◽  
Mycelial Growth ◽  
Colletotrichum Gloeosporioides ◽  
Colletotrichum Acutatum ◽  
Model Parameters ◽  
Pathogenicity Test ◽  
Agar Diffusion ◽  
Wide Range ◽  
Significant Difference ◽  
Diffusion Assay

Microorganisms causing anthracnose diseases have a medium to a high level of resistance to the existing fungicides. This study aimed to investigate neem plant extract (propyl disulfide, PD) as an alternative to the current fungicides against mango’s anthracnose. Microorganisms were isolated from decayed mango and identified as Colletotrichum gloeosporioides and Colletotrichum acutatum. Next, a pathogenicity test was conducted and after fulfilling Koch’s postulates, fungi were reisolated from these symptomatic fruits and we thus obtained pure cultures. Then, different concentrations of PD were used against these fungi in vapor and agar diffusion assays. Ethanol and distilled water were served as control treatments. PD significantly (p ≤ 0.05) inhibited more of the mycelial growth of these fungi than both controls. The antifungal activity of PD increased with increasing concentrations. The vapor diffusion assay was more effective in inhibiting the mycelial growth of these fungi than the agar diffusion assay. A good fit (R2, 0.950) of the experimental data in the Gompertz growth model and a significant difference in the model parameters, i.e., lag phase (λ), stationary phase (A) and mycelial growth rate, further showed the antifungal efficacy of PD. Therefore, PD could be the best antimicrobial compound against a wide range of microorganisms.

scholarly journals Assessment of Streamflow Simulation for a Tropical Forested Catchment Using Dynamic TOPMODEL—Dynamic fluxEs and ConnectIvity for Predictions of HydRology (DECIPHeR) Framework and Generalized Likelihood Uncertainty Estimation (GLUE)

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 317
Author(s):  
Fadhliani Umar ◽  
Zed Zulkafli ◽  
Badronnisa Yusuf ◽  
Siti Nurhidayu
Keyword(s):  
Land Use ◽  
Land Use Change ◽  
Peak Flow ◽  
Uncertainty Estimation ◽  
Model Parameters ◽  
Model Framework ◽  
Behavioral Threshold ◽  
Continuous Simulation ◽  
Generalized Likelihood Uncertainty Estimation ◽  
Streamflow Simulation

Rainfall runoff modeling has been a subject of interest for decades due to a need to understand a catchment system for management, for example regarding extreme event occurrences such as flooding. Tropical catchments are particularly prone to the hazards of extreme precipitation and the internal drivers of change in the system, such as deforestation and land use change. A model framework of dynamic TOPMODEL, DECIPHeR v1—considering the flexibility, modularity, and portability—and Generalized Likelihood Uncertainty Estimation (GLUE) method are both used in this study. They reveal model performance for the streamflow simulation in a tropical catchment, i.e., the Kelantan River in Malaysia, that is prone to flooding and experiences high rates of land use change. Thirty-two years’ continuous simulation at a daily time scale simulation along with uncertainty analysis resulted in a Nash Sutcliffe Efficiency (NSE) score of 0.42 from the highest ranked parameter set, while 25.35% of the measurement falls within the uncertainty boundary based on a behavioral threshold NSE 0.3. The performance and behavior of the model in the continuous simulation suggests a limited ability of the model to represent the system, particularly along the low flow regime. In contrast, the simulation of eight peak flow events achieves moderate to good fit, with the four peak flow events simulation returning an NSE > 0.5. Nonetheless, the parameter scatter plot from both the continuous simulation and analyses of peak flow events indicate unidentifiability of all model parameters. This may be attributable to the catchment modeling scale. The results demand further investigation regarding the heterogeneity of parameters and calibration at multiple scales.

scholarly journals Learning Personalized Itemset Mapping for Cross-Domain Recommendation

2020 ◽  
Author(s):  
Yinan Zhang ◽  
Yong Liu ◽  
Peng Han ◽  
Chunyan Miao ◽  
Lizhen Cui ◽  
...  
Keyword(s):  
Single Domain ◽  
Model Parameters ◽  
The Real ◽  
Cross Domain ◽  
Proposed Model ◽  
Latent Space ◽  
Learning Parameter ◽  
Generation Procedure ◽  
Over Time

Cross-domain recommendation methods usually transfer knowledge across different domains implicitly, by sharing model parameters or learning parameter mappings in the latent space. Differing from previous studies, this paper focuses on learning explicit mapping between a user's behaviors (i.e. interaction itemsets) in different domains during the same temporal period. In this paper, we propose a novel deep cross-domain recommendation model, called Cycle Generation Networks (CGN). Specifically, CGN employs two generators to construct the dual-direction personalized itemset mapping between a user's behaviors in two different domains over time. The generators are learned by optimizing the distance between the generated itemset and the real interacted itemset, as well as the cycle-consistent loss defined based on the dual-direction generation procedure. We have performed extensive experiments on real datasets to demonstrate the effectiveness of the proposed model, comparing with existing single-domain and cross-domain recommendation methods.

scholarly journals Use of Statistical Models for Simulating Transactions on the Real Estate Market

2015 ◽  
Vol 23 (2) ◽  
pp. 102-111 ◽  
Author(s):  
Radosław Cellmer ◽  
Katarzyna Szczepankowska
Keyword(s):  
Probability Distribution ◽  
Real Estate ◽  
Statistical Models ◽  
Real Estate Market ◽  
Model Parameters ◽  
The Real ◽  
The Real Estate ◽  
Transaction Prices ◽  
The Real Estate Market ◽  
Real Estate Prices

Abstract The regularities and relations between real estate prices and the factors that shape them may be presented in the form of statistical models, thanks to which the diagnosis and prediction of prices is possible. A formal description of empirical observation presented in the form of regressive models also offers a possibility for creating certain phenomena in a virtual dimension. Market phenomena cannot be fully described with the use of determinist models, which clarify only a part of price variation. The predicted price is, in this situation, a special case of implementing a random function. Assuming that other implementations are also possible, regressive models may constitute a basis for simulation, which results in the procurement of a future image of the market. Simulation may refer both to real estate prices and transaction prices. The basis for price simulation may be familiarity with the structure of the analyzed market data. Assuming that this structure has a static character, simulation of real estate prices is performed on the basis of familiarity with the probability distribution and a generator of random numbers. The basis for price simulation is familiarity with model parameters and probability distribution of the random factor. The study presents the core and theoretical description of a transaction simulation on the real estate market, as well as the results of an experiment regarding transaction prices of office real estate located within the area of the city of Olsztyn. The result of the study is a collection of virtual real properties with known features and simulated prices, constituting a reflection of market processes which may take place in the near future. Comparison between the simulated characteristic and actual transactions in turn allows the correctness of the description of reality by the model to be verified.

scholarly journals Eye-Tracking Technology in Online Real Estate Rental

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Jie Sun ◽  
Zhiruo Wang ◽  
Xiaoyi Dang ◽  
Yang Zhang
Keyword(s):  
Eye Tracking ◽  
Information Search ◽  
Rental Housing ◽  
Web Page ◽  
Information Display ◽  
Research Results ◽  
The Real ◽  
Display Area ◽  
Significant Difference ◽  
Text Information

In China in recent years, the rental housing market has boomed, but insufficient attention has been paid to microsubject tenants in the market, and there is a lack of research results on tenants’ decision-making processes. In keeping with the characteristics of China’s accommodation-renting population, this study takes as its research object graduating students, who form an important group in the housing rental market, and focuses on the information retrieval process underlying prospective tenants’ rental decisions. First, it investigates tenants’ concerns during the renting process by means of questionnaires. Second, using eye-tracking experiments, the real online renting process is simulated and tenants’ web listings are analyzed qualitatively and quantitatively. In the process of information search, the characteristics and rules of browsing the entry search page, the listings page, and the details page are obtained, and the factors that prospective tenants pay attention to in their search for rental information are obtained. The research results show that initial alphabetical sorting of the term search page can improve the subjects’ efficiency in locating the target keywords, the text information display area of the listings page receives more attention than others, and the real concern factors of the tenants on the page listing details are generally consistent with their selected factors but deviate slightly. Finally, the layout and display of web page information affect how subjects’ attention is distributed, and web page information presents a significant difference in attention between upper and lower pages.

scholarly journals Construction of Intelligent Integrated Model Framework for the Workshop Manufacturing System Via Digital Twin

2021 ◽  
Author(s):  
Zhongyu Zhang ◽  
Zhenjie Zhu ◽  
Jinsheng Zhang ◽  
Jingkun Wang
Keyword(s):  
Real Time ◽  
Production System ◽  
Manufacturing System ◽  
System Optimization ◽  
Production Cycle ◽  
Model Framework ◽  
The Real ◽  
Digital Twin ◽  
Twin Model ◽  
Information Layer

Abstract With the drastic development of the globally advanced manufacturing industry, transition of the original production pattern from traditional industries to advanced intelligence is completed with the least delay possible, which are still facing new challenges. Because the timeliness, stability and reliability of them is significantly restricted due to lack of the real-time communication. Therefore, an intelligent workshop manufacturing system model framework based on digital twin is proposed in this paper, driving the deep inform integration among the physical entity, data collection, and information decision-making. The conceptual and obscure of the traditional digital twin is refined, optimized, and upgraded on the basis of the four-dimension collaborative model thinking. A refined nine-layer intelligent digital twin model framework is established. Firstly, the physical evaluation is refined into entity layer, auxiliary layer and interface layer, scientifically managing the physical resources as well as the operation and maintenance of the instrument, and coordinating the overall system. Secondly, dividing the data evaluation into the data layer and the processing layer can greatly improve the flexible response-ability and ensure the synchronization of the real-time data. Finally, the system evaluation is subdivided into information layer, algorithm layer, scheduling layer, and functional layer, developing flexible manufacturing plan more reasonably, shortening production cycle, and reducing logistics cost. Simultaneously, combining SLP and artificial bee colony are applied to investigate the production system optimization of the textile workshop. The results indicate that the production efficiency of the optimized production system is increased by 34.46%.

scholarly journals Effect of Siguan Acupuncture on Gastrointestinal Motility: A Randomized, Sham-Controlled, Crossover Trial

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Kyung-Min Shin ◽  
Ji-Eun Park ◽  
Sanghun Lee ◽  
Sun-Mi Choi ◽  
Yo-Chan Ahn ◽  
...  
Keyword(s):  
Gastrointestinal Motility ◽  
Acupuncture Treatment ◽  
Gastrointestinal Symptoms ◽  
Sham Acupuncture ◽  
The Body ◽  
Acupuncture Group ◽  
The Real ◽  
Real Acupuncture ◽  
Significant Difference ◽  
Sham Acupuncture Group

Siguan acupoints have been used to treat gastrointestinal symptoms in acupuncture practices for a long time. This study aimed to investigate the effects of Siguan acupuncture on gastrointestinal motility under accelerated conditions using a randomized, sham-acupuncture-controlled, crossover study. Twenty-one healthy male subjects were hospitalized and randomized into either a real acupuncture group (at Siguan acupoints) or a sham acupuncture group. Subjects were administered with mosapride citrate (15 mg a day) for 2 days starting 24 hours before the first acupuncture treatment. Immediately after the administration of radio markers, acupuncture treatment was conducted 4 times at 12-hour intervals. Gastrointestinal motility was assessed using radiograph distribution of the radio-markers located in the small intestine, ascending colon, transverse colon, descending colon, rectum, and outside the body immediately after the first acupuncture treatment and at 6, 12, 24, and 48 hours. After a 2-week washout period, the real acupuncture group in the first session was treated with sham acupuncture in the second session, and vice versa. Gastrointestinal motility was generally reduced in the real acupuncture group compared with the sham acupuncture group throughout the 4 different time points. A significant difference was observed at 24 hours following the first acupuncture treatment (P<0.05).

Lake Levels and Sedimentary Environments During Deposition of the Trego Hot Springs and Wono Tephras in the Lake Lahontan Basin, Nevada, USA

2010 ◽  
Vol 73 (1) ◽  
pp. 118-129 ◽  
Author(s):  
Kenneth D. Adams
Keyword(s):  
Lake Level ◽  
Hot Springs ◽  
Silty Clay ◽  
Lake Levels ◽  
Sediment Sources ◽  
Sedimentary Environments ◽  
Depositional Settings ◽  
Significant Difference ◽  
Predictable Pattern ◽  
Lake Size

The Wono and Trego Hot Springs (THS) tephras are widespread in the Lahontan basin and have been identified in a variety of sedimentary environments at different elevations. Davis (1983) reported lake level to be at about 1256 m when the THS tephra was deposited, an interpretation questioned by Benson et al. (1997) who interpreted lake level to be ≤1177 m at that time. This is a significant difference in lake size with important implications for interpreting the climate that prevailed at that time. Based on new interpretations of depositional settings of the THS bed at multiple sites, the larger lake size is correct. Additional sites containing the Wono tephra indicate that it was deposited when lake level was at about 1217 m in the western subbasins and at about 1205 m in the Carson Sink. Sedimentary features associated with progressively deeper paleowater depths follow a predictable pattern that is modulated by proximity to sediment sources and local slope. Fine to coarse sands with wave-formed features are commonly associated with relatively shallow water. Silty clay or clay dominates in paleowater depths >25 m, with thin laminae of sand and ostracods at sites located adjacent to or downslope from steep mountain fronts.

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