Analyzing the misperception of exponential growth in graphs.

Exponential growth is frequently underestimated, an error that can have a heavy social cost in the context of epidemics. To clarify its origins, we measured the human capacity to extrapolate linear and exponential trends in scatterplots. Four factors were manipulated: the function underlying the data (linear or exponential), the response modality (pointing or venturing a number), the scale on the y axis (linear or logarithmic), and the amount of noise in the data. While linear extrapolation was precise and largely unbiased, we observed a consistent underestimation of noisy exponential growth, present for both pointing and numerical responses. A biased ideal-observer model could explain these data as an occasional misperception of noisy exponential graphs as quadratic curves. Importantly, this underestimation bias was mitigated by participants’ math knowledge, by using a logarithmic scale, and by presenting a noiseless exponential curve rather than a noisy data plot, thus suggesting concrete avenues for interventions.

An Optimization Algorithm for Exponential Curve Model of Single Pile Bearing Capacity

The ultimate bearing capacity of single pile is very important to engineering safety, so correctly predicting its value becomes an important part of engineering safety. Based on the traditional exponential curve model, a parameter optimization algorithm of the exponential curve model of single pile bearing capacity, which combines the golden section method and the linear least square method, is proposed. In order to verify the reliability of the proposed optimization algorithm, the measured data of the building engineering in the literature were optimized and calculated. Through comparison, it is found that the optimization algorithm is closer to the measured value than the traditional exponential curve model algorithm, which can better guide the engineering practice, and verify the effectiveness and superiority of the proposed parameter optimization method.

Multistage unidirectionally migrating canyons and the evolution of their trajectories in the canyon zone in the Baiyun Sag, northern South China Sea: Insights into canyon genesis

Layers in deep-sea slope area can serve as indexes of various sedimentary dynamic evolutions, despite their complicated processes. The sedimentary architecture evolution in a slope can exhibit different stratigraphic records, especially in terms of canyon migration trajectories. We use the northern continental slope of the South China Sea as a case study, where the main straight canyons in this area have developed. After describing the core samples and performing the corresponding well seismic data calibration and sedimentary parameter statistics, we identified two different patterns of canyon trajectory evolutions: the “exponential curve-shaped” canyon migration trajectory path and the “logarithmic curve-shaped” path. The “exponential curve-shaped” canyon migration trajectory path is distinguished by a lower layer of coarse-grained sediment and an upper layer of fine-grained sediment, and the “logarithmic curve-shaped” canyon migration trajectory exhibits the opposite trend, i.e., fine-grained sediment on the bottom and coarse-grained sediment on the top. Based on the above phenomenon, we quantitatively calculated the flow and deposition rates of turbidites and determined their genesis. We infer that due to the different grain size characteristics of different types of turbidites, the turbidites show different flow patterns. Coarse-grained turbidites are characterized by lower vertical erosion rates and higher lateral abrasion rates, while fine-grained turbidites have exactly the opposite characteristic. Thus, the “exponential curve-shaped” migration trajectory is mainly formed by the coarse-grained turbidity current erosion in the first stage (later migration stage) and the deposition of fine-grained turbidites in the latter stage (vertical aggradation stage). In contrast, the “logarithmic curve-shaped” turbidites are developed by the opposite sedimentary process.

Formaldehyde Adsorption–Desorption of Poplar Bark

This study investigated how the Populus × euramericana cv. Pannónia bark behaves in an environment containing formaldehyde. Prism shaped samples were formed from the bark and the prisms were kept in formaldehyde contaminated atmosphere for 1, 2, 5, 10, 18 and 36 days. After the contamination, the amount of the formaldehyde adsorbed and later the desorbed was measured. The formaldehyde content of the uncontaminated poplar bark was 0.0036 mg/g. The amount of bound formaldehyde showed a saturation curve as a function of time. The formaldehyde adsorption reached an equilibrium value of 0.9 mg HCHO/g bark. The emission of formaldehyde from contaminated bark samples showed an exponential curve as a function of time and some residual formaldehyde content was detected after the formaldehyde was released.

PENGARUH MUATAN TRUK BERLEBIH TERHADAP NILAI KERUSAKAN DAN BIAYA PEMELIHARAAN JALAN RUAS CIKAMPEK-PAMANUKAN

<span><em>Cikampek-Pamanukan Road is the main route of Pantura in the area ofWest Java Province. The proportion </em><span><em>of truck traffic in the lane tend to be higher along with the high traffic of goods. The research conducted in </em><span><em>the Cikampek-Pamanukan section aims to analyze the magnitude of the effect of overloaded truckloads on the </em><span><em>road damage value, to analyze the magnitude of the effect of overhead truckloads on road maintenance costs, </em><span><em>and the costs incurred due to excessive truckloads. Methods The study was conducted by conducting a road </em><span><em>damage survey from March to December 2016, and an overload truck survey using WIM tools from January </em><span><em>to December 2014. The results showed the effect of overload loading on vehicle damage (ESAL) in the form </em><span><em>of exponential curve with the equation Y = 23,722e</em><span><em>0,0264x</em><span><em>. The influence of overload truck volume on road</em><br /><span><em>damage resulted in Cirebon Y = 7,4823066 - 0,0000048X1 + 0, 004239X2, and Jakarta Y = 172,9392 + </em><span><em>0,00009X1 - 0,00830X2. The effect of overloaded truckloads on road maintenance costs with over 10% MST </em><span><em>loading, resulting in a cost of Rp. 733.180.483,72</em></span></span></span></span></span></span></span></span></span></span><br /><br class="Apple-interchange-newline" /></span></span></span>

Performance evaluation of flow duration curves regionalization methods

ABSTRACT The main objective of the study was the evaluation of Characteristic Values and Exponential Curve methods as alternatives for flow permanence curves regionalization. Additionally, the use of regional flow indicators for the appropriation of reference flows associated with flow permanence curves was evaluated. The study area covered the Itapemirim and Itabapoana rivers watersheds, the most important located in the southern portion of the Espírito Santo state (Brazil). The Characteristic Values method presented best results in the flow permanence curves regionalization work. It was also concluded that the regional indicators represent a simple and consistent alternative for study area reference flows estimation.