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In recent years, the usage of drones in last‐mile logistics has stirred great interest in the operations research community. Many papers have considered schemes of hybrid truck‐and‐drone delivery. In this paper, we focus on the Multivisit Drone Routing Problem with Edge Launches (MVDRP‐EL) which assumes: a heterogenous set of packages, a drone capable of carrying multiple packages at a time and that can be launched and retrieved along an edge, a flexible launch/retrieval site set, and a user‐defined energy depletion function. We believe this paper is the first to exploit edge launch ability through a global continuous approach. In this context, we propose an original formulation based on the Covering Salesman Problem to compute a valid lower bound for the problem and an iterative solution method to determine a MVDRP‐EL solution with quality launch/retrieval sites along the road network edges. Each iteration of the solution method consists of two phases. In the first phase, the road network edges are discretized to obtain launch/retrieval sites, and a first solution is determined. In the second phase, the truck route is set and we reduce the completion time by carefully synchronizing truck and drone routes by solving an original Mixed Integer Second Order Cone Program. The lower bound formulation and the proposed method have been tested on several instances and results indicate the effectiveness of the proposed method and the potential value of launching along an edge, respectively. [ABSTRACT FROM AUTHOR]

Cocrystals can be defined as crystalline solids composed of at least two compounds in a stoichiometric ratio which interact nonionically. While one of the components is an active pharmaceutical ingredient (API) the term ‘pharmaceutical cocrystal’ could be applied. These are the subject of interest in academic and industrial research as they offer better control over physicochemical, mechanical and pharmacokinetic properties of API while its therapeutic activity remains intact. Commercial success of this approach can be confirmed by the number of marketed pharmaceutical cocrystal drug forms. Despite the range of cocrystallization methods introduced, it is challenging to propose a technique meeting industrial requirements such as scalability or continuousness of the process with respect to ‘green chemistry’ principles being reduction of solvents use. This paper covers the criteria of cocrystallization method selection and presents techniques potentially applicable for large-scale purposes such as Hot Melt Extrusion, Matrix Assisted Cocrystallization and spray congealing with advantages and limitations of those. Within mechanochemical methods of obtaining cocrystals, Matrix Assisted Cocrystallization (MAC) is a promising candidate for industrial-scale use as it is a continuous, one-step, solvent-free technique offering high control over process parameters (e.g. temperature, feed rate, screw speed, screw configuration, extruder type) in order to increase the efficiency of the synthesis and provide high quality product. The addition of polymer facilitates the extrusion and enables conducting the process at lower temperature to prevent degradation of thermolabile substances. Furthermore, cocrystals embedded in polymeric matrix can exhibit the improvement of dissolution rate or compressibility. Additionally, the MAC can be coupled with Process Analytical Technology (PAT) tools to provide real-time data for manufacturing process monitoring and control of product quality.

Abstract: A typical assessment of the strength of forensic DNA evidence is based on a population genetic model and estimated allele frequencies determined from a population database. Some experts provide a confidence or credible interval which takes into account the sampling variation inherent in deriving these estimates from only a sample of a total population. This interval is given in conjunction with the statistic of interest, be it a likelihood ratio (LR), match probability, or cumulative probability of inclusion. Bayesian methods of addressing database sampling variation produce a distribution for the statistic from which the bound(s) of the desired interval can be determined. Population database sampling uncertainty represents only one of the sources of uncertainty that affects estimation of the strength of DNA evidence. There are other uncertainties which can potentially have a much larger effect on the statistic such as, those inherent in the value of Fst, the weights given to genotype combinations in a continuous interpretation model, and the composition of the relevant population. In this paper we model the effect of each of these sources of uncertainty on a likelihood ratio (LR) calculation and demonstrate how changes in the distribution of these parameters affect the reported value. In addition, we illustrate the impact the different approaches of accounting for sampling uncertainties has on the LR for a four person mixture. [Copyright &y& Elsevier]

Background and purpose: Pain relief is one of the major parts in midwifery. One method of medication for pain relieving in labor, is using the Entonox gas. The present study is conducted to compare the continuous and intermittent use of Entonox gas in the reduction of labor pain. Material and Methods: This study is a clinical trial conducted on 100 pregnant women hospitalized in Shahidan Mobini Hospital in Sabzevar (2013). The research samples were selected based on purposing sampling method and were randomly divided into two groups using Entonox. Research tools included interview forms, registration forms, medical information derived from the parturient case and visual pain scale. Statistical analyses were performed by Spss 17 software, statistical t-test and chi- square test. Results: The average pain intensity in total active phase in intermittent group was 6.2±2.4 and in continuous group 5.4±2.5 which showed no significant difference between the two groups (P= 0.127). The average pain intensity second stage of labor in intermittent group was 7.8±2.8 and in continuous group 6.5±3.7 which showed no significant difference between the two groups (P= 0.06). There was no significant statistical difference between two groups in the first and the fifth minute Apgar score (P>0.05) Conclusion: It seems that the application of Entonox in continuous form is a better way to control labor pain than the intermittent method which is the conventional method of using Entonox, and has no specific side effects for both the mother and the baby. [ABSTRACT FROM AUTHOR]

This paper considers a class of highly stable block methods for numerically solving initial value problems (IVPs) in ordinary differential equations (ODEs). The boundary locus of the proposed parallel one-block, r-output point algorithms shows that the new schemes are A-stable for output points r = 2(2)8 and A( α)-stable for output points r = 10(2)20, where r is the number of processors in a particular block method in the family. Numerical results of the block methods are compared with the second derivative linear multistep method in [8]. [ABSTRACT FROM AUTHOR]

In this paper, we consider a family of hybrid linear multistep methods (LMM) with reasonable error order for the numerical solution of stiff initial value problems (IVPs) in ordinary differential equations (ODEs). The methods are A(α)-stable for k = 1, ...,9. [ABSTRACT FROM AUTHOR]

In this paper, we present a class of A( α)-stable hybrid linear multistep methods for numerical solving stiff initial value problems (IVPs) in ordinary differential equations (ODEs). The method considered uses a second derivative like the Enright's second derivative linear multistep methods for stiff IVPs in ODEs. [ABSTRACT FROM AUTHOR]

Time-integrated (typically 24-h) filter-based methods (historical methods) form the underpinning of our understanding of the fate, impact of source emissions at receptor locations (source impacts), and potential health and welfare effects of particulate matter (PM) in air. Over the last 40 years, many of these methods have been thoroughly evaluated and there is reasonable confidence with what they measure and associated uncertainties. These methods require transport of samples collected in the field to a laboratory for analysis of PM properties of interest. Over the last decade, significant progress has occurred in the development and evaluation of continuous and semi-continuous methods that combine the collection and chemical or physical property analysis into one instrument. These methods are placed in the field, providing often near-real time data, most with hourly time-resolution or better from bulk to single particle information from a few nanometers to 10 µm. Many of the continuous chemical property methods developed and tested still require additional evaluation and comparison between themselves and to historical methods. The latter are the primary basis for comparison since in-the-field tests, through the inlet reference standards are not available for most PM components. Despite lesser confidence in these methods relative to historical methods, data generated from these methods have greatly enhanced the application of approaches to link and quantify the impact of source emissions at receptor sites and to associate PM with health effects, as well as significantly advancing our understanding of atmospheric chemistry and the fate of PM in air. This paper briefly reviews the two primary modelling methods for estimating source contributions at receptor locations and current measurement methods with a focus on continuous measurements. [ABSTRACT FROM AUTHOR]

We introduce a unifying framework for hybridization of finite element methods for second order elliptic problems. The methods fitting in the framework are a general class of mixed-dual finite element methods including hybridized mixed, continuous Galerkin, nonconforming, and a new, wide class of hybridizable discontinuous Galerkin methods. The distinctive feature of the methods in this framework is that the only globally coupled degrees of freedom are those of an approximation of the solution defined only on the boundaries of the elements. Since the associated matrix is sparse, symmetric, and positive definite, these methods can be efficiently implemented. Moreover, the framework allows, in a single implementation, the use of different methods in different elements or subdomains of the computational domain, which are then automatically coupled. Finally, the framework brings about a new point of view, thanks to which it is possible to see how to devise novel methods displaying very localized and simple mortaring techniques, as well as methods permitting an even further reduction of the number of globally coupled degrees of freedom [ABSTRACT FROM AUTHOR]

Abstract: In this paper we propose the R-K type Landweber iteration and investigate the convergence of the method for nonlinear ill-posed problem where is a nonlinear operator between Hilbert space H. Moreover, for perturbed data with noise level we prove that the convergence rate is under appropriate conditions. Finally, the numerical performance of this R-K type Landweber iteration for a nonlinear convolution equation is compared with the Landweber iteration. [Copyright &y& Elsevier]

In this paper, we present a continuous method for convex programming (CP) problems. Our approach converts first the convex problem into a monotone variational inequality (VI) problem. Then, a continuous method, which includes both a merit function and an ordinary differential equation (ODE), is introduced for the resulting variational inequality problem. The convergence of the ODE solution is proved for any starting point. There is no Lipschitz condition required in our proof. We show also that this limit point is an optimal solution for the original convex problem. Promising numerical results are presented. [ABSTRACT FROM AUTHOR]

The globally projected dynamical system has received considerable attention due to its low complexity for variational inequality and optimization computation. This paper obtains further results on the global convergence, asymptotic stability, and exponential stability of this system respectively under monotonicity of the mapping, strict monotonicity of the mapping, and positive definiteness of the Jacobian matrix of the mapping. The new results improve existing ones and cover the classical stability results of autonomous dynamical systems as special cases. An application to constrained optimization and complementarity problems is given to show the applied significance of the results. [ABSTRACT FROM AUTHOR]