Determination of the Uncertainties in S-Curve Logistic Fits

Look-up tables and graphs are provided for determining the uncertainties during logistic fits, on the three parameters M, α and to describing an S-curve of the form: S(t) = M/(1+exp(-α(t-t0))).The uncertainties and the associated confidence levels are given as a function of the uncertainty on the data points and the length of the historical period. Correlations between these variables are also examined; they make “what-if” games possible even before doing the fit.The study is based on some 35,000 S-curve fits on simulated data covering a variety of conditions and carried out via a χ2 minimization technique. A rule-of-thumb general result is that, given at least half of the S-curve range and a precision of better than 10% on each historical point, the uncertainty on M will be less than 20% with 90% confidence level.

A Novel Optimal Robotized Parking System Using Advanced Wireless Sensor Network

This article addresses the importance of parking system which makes the movement of moving vehicles to be unrestricted thus providing integration between hominid classification and sensing systems. If two distinct systems are combined, then all the vehicles can monitor the parking space, and they can directly move towards the destination end within short span of time. In addition for this type of establishment, rapidity of transportation vehicles is calculated with error minimization technique where all technical hitches will be avoided by sustaining the user constraints. Further, to solve the designed user constraints, a nonlinear optimization which is termed as machine learning algorithm is introduced for avoiding high loss during packet transmission technique, and percentage of efficiency is analyzed using simulated results with network simulator (NS2). Moreover, from simulated results, it is substantiated that the projected method on automatic parking of vehicles provides high efficient operation, and even cost of installation is reduced.

Impacts of Uniform Magnetic Field and Internal Heated Vertical Plate on Ferrofluid Free Convection and Entropy Generation in a Square Chamber

The heat transfer enhancement and fluid flow control in engineering systems can be achieved by addition of ferric oxide nanoparticles of small concentration under magnetic impact. To increase the technical system life cycle, the entropy generation minimization technique can be employed. The present research deals with numerical simulation of magnetohydrodynamic thermal convection and entropy production in a ferrofluid chamber under the impact of an internal vertical hot sheet. The formulated governing equations have been worked out by the in-house program based on the finite volume technique. Influence of the Hartmann number, Lorentz force tilted angle, nanoadditives concentration, dimensionless temperature difference, and non-uniform heating parameter on circulation structures, temperature patterns, and entropy production has been scrutinized. It has been revealed that a transition from the isothermal plate to the non-uniformly warmed sheet illustrates a rise of the average entropy generation rate, while the average Nusselt number can be decreased weakly. A diminution of the mean entropy production strength can be achieved by an optimal selection of the Lorentz force tilted angle.

Using Eight-Variable Karnaugh Maps to Unravel Hidden Technicalities in Qualitative Comparative Analysis

We use a regular and modular eight-variable Karnaugh map to reveal some technical details of Boolean minimization usually employed in solving problems of Qualitative Comparative Analysis (QCA). We utilize as a large running example a prominent eight-variable political-science problem of sparse diversity (involving a partially-defined Boolean function (PDBF), that is dominantly unspecified). We recover the published solution of this problem, showing that it is merely one candidate solution among a set of many equally-likely competitive solutions. We immediately obtain one of these rival solutions, that looks better than the published solution in two aspects, namely: (a) it is based on a smaller minimal set of supporting variables, and (b) it provides a more compact Boolean formula. However, we refrain from labelling our solution as a better one, but instead we stress that it is simply un-comparable with the published solution. The comparison between any two rival solutions should be context-specific and not tool-specific. In fact, the Boolean minimization technique, borrowed from the area of digital design, cannot be used as is in QCA context. A more suitable paradigm for QCA problems is to identify all minimal sets of supporting variables (possibly via integer programming), and then obtain all irredundant disjunctive forms (IDFs) for each of these sets. Such a paradigm stresses inherent ambiguity, and does not seem appealing as the QCA one, which usually provides a decisive answer (irrespective of whether it is justified or not).The problem studied herein is shown to have at least four distinct minimal sets of supporting variables with various cardinalities. Each of the corresponding functions does not have any non-essential prime implicants, and hence each enjoys the desirable feature of having a single IDF that is both a unique minimal sum and the complete sum. Moreover, each of them is unate as it is expressible in terms of un-complemented literals only. Political scientists are invited to investigate the meanings of the (so far) abstract formulas we obtained, and to devise some context-specific tool to assess and compare them.

BILCAP-study: Should patients with resected biliary tract cancer really receive adjuvant chemotherapy with capecitabine?

Objective According to the 2019 published ASCO guidelines patients with resected biliary tract cancer should be offered adjuvant capecitabine chemotherapy based solely on the results of the BILCAP trial. Aim of this work is to analyze the quality of the BILCAP trial. Methods Design, conduct, statistics and reporting of the study were analyzed according to the Delphi list and the CONSORT checklist. The risk of bias was assessed using the Cochrane Risk of Bias Tool. Results Several shortcomings could be identified in the study regarding design, conduct, statistics and reporting. The BILCAP study is a randomized, controlled, multicenter, phase 3 study which was done across 44 specialist hepatopancreatobiliary centres in the UK. Despite the inclusion of high specialized centres, the number of included patients each year for each center is extremely low. In particular, a total of 447 patients were included by 44 centers over a period of 11 years, meaning that less than 1 patient was included in this study every year by each center. However, the analysis was not adjusted for center which was one of the stratification factors. Follow up treatment for patients who had disease recurrence was not recorded. Randomization procedure is not well described. Minimization technique was adopted for stratification but mode of application is poorly reported and the choice of variables not justified. No blinding was present. Extensive power evaluations after adjusting the number of needed events, due to lower event rates than expected, were not done. For the observed HR = 0.81 with 234 events statistical power is only around 37%. 4 out of 9 items of the Delphi list and 6 out of 35 items of the CONSORT checklist were not properly addressed. According to the Cochrane Risk of Bias Tool (RoB 2) the overall risk-of-bias judgment for the outcome overall survival of the BILCAP study was “some concerns”. Almost all authors declared to have received funds from pharmaceutical companies, so a conflict of interest cannot be excluded. Additionally, the funding agency for this study (Cancer Research UK and Roche) had an advisory role in design and the first author of the BILCAP study was also involved in the generation of the ASCO guideline. Conclusion Based on the results of this study there is not enough evidence for the administration of adjuvant chemotherapy with capecitabine in patients with resected biliary tract cancer.

Micromechanical Analysis in Applications of Active Mono-Slip and Continuum Dislocations in the MDCM

The key purpose of this paper is to propose a mono-slip-dependent continuum dislocation method for matrix-dominated composite structure (MDCS) analysis. The methodology focuses on dissipation energy theories utilizing a continuum dislocation method (CDM) integrated with small-strain kinematics. The mathematical modeling of the CDM comprises active mono-slip system formulations, thermodynamic dislocation analysis (TDA), free energy dissipation analysis, and the progression of dislocations. Furthermore, zero and non-zero energy dissipation due to dislocation progression is formulated by using an energy minimization technique with variational calculus. The numerical analysis, performed with Wolfram Mathematica©, is presented using zero and non-zero energy dissipation energy formulations. The outcomes indicate that the formulated approach can be effective for obtaining optimal analysis results for matrix-dominated composite (MDC) materials with a mono-slip system. In sum, this study confirms the feasibility of using the proposed approach to investigate MDCS with inclusions.