Efficient approximate analytical methods for nonlinear fuzzy boundary value problem

This paper aims to solve the nonlinear two-point fuzzy boundary value problem (TPFBVP) using approximate analytical methods. Most fuzzy boundary value problems cannot be solved exactly or analytically. Even if the analytical solutions exist, they may be challenging to evaluate. Therefore, approximate analytical methods may be necessary to consider the solution. Hence, there is a need to formulate new, efficient, more accurate techniques. This is the focus of this study: two approximate analytical methods-homotopy perturbation method (HPM) and the variational iteration method (VIM) is proposed. Fuzzy set theory properties are presented to formulate these methods from crisp domain to fuzzy domain to find approximate solutions of nonlinear TPFBVP. The presented algorithms can express the solution as a convergent series form. A numerical comparison of the mean errors is made between the HPM and VIM. The results show that these methods are reliable and robust. However, the comparison reveals that VIM convergence is quicker and offers a swifter approach over HPM. Hence, VIM is considered a more efficient approach for nonlinear TPFBVPs.

Numerical Solution of the Time-Depending Flow of Immiscible Fluids with Fuzzy Boundary Conditions

Fluid flow modeling using fuzzy boundary conditions is one of the viable areas in biofluid mechanics, drug suspension in pharmacology, as well as in the cytology and electrohydrodynamic analysis of cerebrospinal fluid data. In this article, a fuzzy solution for the two immiscible fluid flow problems is developed, which is motivated by biomechanical flow engineering. Two immiscible fluids, namely micropolar and Newtonian fluid, are considered with fuzzy boundary conditions in the horizontal channel. The flow is considered unsteady and carried out by applying a constant pressure gradient in the X-direction of the channel. The coupled partial differential equations are modeled for fuzzy profiles of velocity and micro-rotation vectors then the numerical results are obtained by the modified cubic B - spline differential quadrature method. The evolution of membership grades for velocity and microrotation profiles has been depicted with the fuzzy boundaries at the channel wall. It is observed that Micropolar fluid has a higher velocity change than Newtonian fluid, and both profiles indicate a declining nature toward the interface.

Scale-aware Auto-context-guided Fetal US Segmentation with Structured Random Forests

Accurate measurement of fetal biometrics in ultrasound at different trimesters is essential in assisting clinicians to conduct pregnancy diagnosis. However, the accuracy of manual segmentation for measurement is highly user-dependent. Here, we design a general framework for automatically segmenting fetal anatomical structures in two-dimensional (2D) ultrasound (US) images and thus make objective biometric measurements available. We first introduce structured random forests (SRFs) as the core discriminative predictor to recognize the region of fetal anatomical structures with a primary classification map. The patch-wise joint labeling presented by SRFs has inherent advantages in identifying an ambiguous/fuzzy boundary and reconstructing incomplete anatomical boundary in US. Then, to get a more accurate and smooth classification map, a scale-aware auto-context model is injected to enhance the contour details of the classification map from various visual levels. Final segmentation can be obtained from the converged classification map with thresholding. Our framework is validated on two important biometric measurements, which are fetal head circumference (HC) and abdominal circumference (AC). The final results illustrate that our proposed method outperforms state-of-the-art methods in terms of segmentation accuracy.

Conceptual Ambiguity in Coding the Categories of Peace Agreement and Peace Process

Within the field of peace and conflict studies, data-production on peace agreements has rapidly increased. One complicated task for scholars and practitioners alike is understanding the relationships between peace agreements and the relationships between agreements and processes. For example, discerning when an agreement establishes continuity with previous agreements and, thus, belongs to the same peace process or when an agreement signals the start of a new peace process is not straightforward. In this study, I highlight what appears to be a fuzzy boundary for categorizing some disciplinary core concepts which, in turn, can cause our data to be unreliable. As a point of comparison, I investigate how two major peace agreement datasets – UCDP Peace Agreement Dataset and PA-X Peace Agreement Dataset – associate peace agreements with peace processes and find differences and ambiguities with respect to how they are coded in both databases. As a result of such inconsistencies, analyses drawn from these data can have different outputs and lead to misunderstandings about peace processes. Here, I demonstrate the disciplinary need for clearer principles to effectively associate peace agreements with peace processes and then argue for developing a disciplinary standard for the criteria used to operationalize peace processes. Crucially, a standard method for aggregating agreements into processes will facilitate consistent data production across databases.

Mission-Oriented Policy for Innovation and the Fuzzy Boundary of Market Creation: the Brazilian Shipbuilding Case

Recent literature has called attention to the significance of mission-oriented policies (MOPs) in setting the directions of change, market creation, and economic development. The aim of this article is to analyze and discuss the main challenges of setting MOPs in the context of developing countries. We do so by looking at the recent development of the Brazilian shipbuilding sector where an entire institutional setting was put in place to boost technological and industrial development. We investigate the policies set for the sector to create a market, stimulate the industry, and promote innovation. Results show that, while the set of policies emplaced was able to give an initial boost in the sector, coordination uncertainties and high capability-building costs precipitated the failure of the industry to catchup with international competitors. We argue that there is a fuzzy boundary between policy expectations for market creation and the actual possibilities of building an industry.