In this study, we analyzed the factors affecting the spatial distribution of pedestrians in the Meieki district of Nagoya by comparing a log-log model with a generalized linear model. We classified ...all the factor variables into four categories. To compare the importance of each variable in the model, we introduced mean standardized partial differential coefficients value. The results show that the generalized linear model is superior to the log-log model and the spatial distribution of pedestrians in the Meieki district is strongly correlated with the segment angular integration value(R=1200).
Betaine-based polyfluoroalkyl surfactants are major perfluoroalkyl and polyfluoroalkyl surfactants (PFASs) found in many aqueous film-forming foams (AFFF) impacted sites, while the transport behavior ...(i.e., mobility and adsorption) of PFAS-based betaines in groundwater and natural geosorbents interfaces remains unclear. To fill the knowledge gap, partitioning between of 15 AFFF-relevant PFASs, including 3 fluorotelomer sulfonates (FTSAs) and 3 polyfluoroalkyl betaines, and a model soil organic matter (SOM) were systematically assessed using a modified column chromatography approach. Results show that the retention of FTSAs (perfluoroalkyl chain-length of 4, 6, and 8) to SOM are similar to that of corresponding legacy perfluoroalkyl sulfonic acids (PFSAs) with the same chain length; FTSAs also respond to changes in solution chemistry similarly as PFSAs. At a solution pH of 5.9, based on the equilibrium speciation of the betaine-PFASs together with the experimental observations, the predominance of the neutral species over zwitterions gives rise to the relatively higher retention of polyfluoroalkyl betaines than perfluoroalkyl carboxylic acids (PFCAs) of equivalent chain-length. Sorption edges (minimal and maximal logKoc values over a defined pH range) determined for three polyfluoroalkyl betaines are: 1.90–3.81 for perfluorooctaneamide betaine (PFOAB), 2.03–2.65 for perfluoroctane sulfonamide betaine (PFOSB), and < 3.04 for 6:2 fluorotelomer sulfonamide betaine (6:2 FTAB). Moreover, the increase in pH reduces the sorption of all PFASs to SOM. Increasing calcium ion (concentration ranges from 0.5 to 50 mM) has enhanced the sorption of anionic PFASs to SOM but decreased the sorption of the polyfluoroalkyl betaines. These findings are expected to improve the ability to anticipate and predict the possible subsurface locations (i.e., predominantly in groundwater or sorbed to soil) of both novel and legacy PFASs.
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•Retention of FTSAs on SOM is similar to that of PFSAs of equivalent chain length.•Polyfluoroalkyl betaines exhibit stronger sorption to SOM than PFCAs of equivalent chain length.•Increase in pH reduces sorption of all PFASs to SOM.•Increasing Calcium ion (0.5–50 mM) reduces sorption of the polyfluoroalkyl betaines.
Many software engineering activities process the events contained in log files. However, before performing any processing activity, it is necessary to parse the entries in a log file, to retrieve the ...actual events recorded in the log. Each event is denoted by a log message, which is composed of a fixed part-called (event) template-that is the same for all occurrences of the same event type, and a variable part, which may vary with each event occurrence. The formats of log messages, in complex and evolving systems, have numerous variations, are typically not entirely known, and change on a frequent basis; therefore, they need to be identified automatically. The log message format identification problem deals with the identification of the different templates used in the messages of a log. Any solution to this problem has to generate templates that meet two main goals: generating templates that are not too general, so as to distinguish different events, but also not too specific, so as not to consider different occurrences of the same event as following different templates; however, these goals are conflicting. In this paper, we present the MoLFI approach, which recasts the log message identification problem as a multi-objective problem. MoLFI uses an evolutionary approach to solve this problem, by tailoring the NSGA-II algorithm to search the space of solutions for a Pareto optimal set of message templates. We have implemented MoLFI in a tool, which we have evaluated on six real-world datasets, containing log files with a number of entries ranging from 2K to 300K. The experiments results show that MoLFI extracts by far the highest number of correct log message templates, significantly outperforming two state-of-the-art approaches on all datasets.
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New strategies to potentially improve drug safety and efficacy emerge with allosteric programs. Biased allosteric modulators can be designed with high subtype selectivity and defined ...receptor signaling endpoints, however, selecting the most meaningful parameters for optimization can be perplexing. Historically, “potency hunting” at the expense of physicochemical and pharmacokinetic optimization has led to numerous tool compounds with excellent pharmacological properties but no path to drug development. Conversely, extensive physicochemical and pharmacokinetic screening with only post hoc bias and allosteric characterization has led to inefficacious compounds or compounds with on-target toxicities. This field is rapidly evolving with new mechanistic understanding, changes in terminology, and novel opportunities. The intent of this digest is to summarize current understanding and debates within the field. We aim to discuss, from a medicinal chemistry perspective, the parameter choices available to drive SAR.
Process-oriented data mining (process mining) uses algorithms and data (in the form of event logs) to construct models that aim to provide insights into organisational processes. The quality of the ...data (both form and content) presented to the modeling algorithms is critical to the success of the process mining exercise. Cleaning event logs to address quality issues prior to conducting a process mining analysis is a necessary, but generally tedious and ad hoc task. In this paper we describe a set of data quality issues, distilled from our experiences in conducting process mining analyses, commonly found in process mining event logs or encountered while preparing event logs from raw data sources. We show that patterns are used in a variety of domains as a means for describing commonly encountered problems and solutions. The main contributions of this article are in showing that a patterns-based approach is applicable to documenting commonly encountered event log quality issues, the formulation of a set of components for describing event log quality issues as patterns, and the description of a collection of 11 event log imperfection patterns distilled from our experiences in preparing event logs. We postulate that a systematic approach to using such a pattern repository to identify and repair event log quality issues benefits both the process of preparing an event log and the quality of the resulting event log. The relevance of the pattern-based approach is illustrated via application of the patterns in a case study and through an evaluation by researchers and practitioners in the field.
•A set of data imperfection patterns for event logs is introduced.•The data imperfection patterns enable systematic approach to data cleaning.•The usefulness of the patterns is demonstrated in a process mining case study.•The patterns have been evaluated with process mining experts and practitioners.
In this paper, a joint application of simplified Tomlinson-Harashima precoding (THP) and M -log-maximum a posteriori probability ( M -log-MAP) decoder at transceivers is proposed for low complexity ...faster than Nyquist (FTN) 4-ary pulse amplitude modulation (PAM4) signaling. A THP with only two taps is applied at the transmitter for FTN-induced inter-symbol interference elimination and equalization-induced noise amplification issue mitigation, which effectively relieves the burden of the receiver. At the receiver, a low complexity M-log-MAP decoder is equipped for residual impairments cancellation, thus a feedback channel is not required to accurately obtain the channel state information for the transmitter. Taking advantage of this collaborative approach, the proposed scheme performs much better than applying the two schemes separately. We experimentally demonstrate the proposed scheme in 70, 75, and 80GBaud PAM4 systems with a 32-GHz brick-wall filter, corresponding to 0.914, 0.853, and 0.8 FTN compression factor, respectively. The results show that the 80GBaud PAM4 signal is successfully transmitted over 2-km single mode fiber with the bit-error-rate (BER) under the 7% hard-decision forward error correction (HD-FEC) threshold of 3.8×10 −3 . It is also observed that the proposed scheme shows about 0.7dB receiver sensitivity improvement compared to the error propagation-free decision feedback equalizer, namely the performance upper bound of the THP, at BER of 7% HD-FEC threshold in a 75GBaud FTN PAM4 system. According to the experimental results, the proposed scheme is a promising solution for bandwidth-starved low-cost intra-datacenter interconnect.
Postfire restoration practices encompass those which aim to reduce negative wildfire impacts and to improve burned area rehabilitation. Contour-felled log debris (CFD) and log erosion barriers (LEB) ...are two techniques used worldwide on hillslopes after wildfires in order to avoid soil erosion. In this context, it is essential to evaluate how these restoration techniques can affect soil properties by increasing or decreasing wildfire impacts. The effects on several physico-chemical and biological soil parameters were here investigated by comparing three differently treated post-fire zones. Three randomly 20 × 20 m distributed plots were set up five years after wildfire in the burned and contour-felled log debris areas (CFD plots), three others in the burned and log erosion barriers area (LEB plots) and three others in the burned and unmanaged plots (BNa plots). Three more plots were set up in an unburned area close to the burned area (UB plots). The results revealed that LEB and, to a lesser extent CFD, improved postfire soil quality, which a priori favoured helped the recovery of ecosystem functions. Our results also indicate greater efficacy of LEB and CFD in retaining sediments by limiting loss of nutrients, which is considered essential to recover vegetation after a wildfire. Post-fire restoration plans should consider the use of LEB and CFD when aiming to favour ecosystem recovery processes after wildfires.
•Hillslope treatments improve the microbiological soil properties.•Soil properties improvement is more clearly in log erosion barriers.•Contour-felled log debris and log erosion barriers generate higher SOM.•Log erosion barriers make higher nutrient content.
We introduce the notion of generalized MR log canonical surfaces and establish the minimal model theory for generalized MR log canonical surfaces in full generality.
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