Certified Roundoff Error Bounds using Bernstein Expansions and Sparse Krivine-Stengle Representations

Floating point error is an inevitable drawback of embedded systems implementation. Computing rigorous upper bounds of roundoff errors is absolutely necessary to the validation of critical software. This problem is even more challenging when addressing non-linear programs. In this paper, we propose and compare two new methods based on Bernstein expansions and sparse Krivine-Stengle representations, adapted from the field of the global optimization to compute upper bounds of roundoff errors for programs implementing polynomial functions. We release two related software package FPBern and FPKiSten, and compare them with state of the art tools. We show that these two methods achieve competitive performance, while computing accurate upper bounds by comparison with other tools.Comment: 20 pages, 2 table

A Markov chain model for drop ratio on one-packet buffers DTNs

Most of the efforts to characterize DTN routing are focused on the trade-off between delivery ratio and delay. Buffer occupancy is usually not considered a problem and most of the related work assumes infinite buffers. In the present work, we focus on the drop ratio for message forwarding considering finite buffers. We model message drops with a continuous time Markov chain (CTMC). To the best of our knowledge, there is no previous work with such approach. We focus on the worst case with 1-packet buffers for message forwarding in homogeneous inter-contact times (ICT) and 2-class heterogeneous ICT. Our main contribution is to link the encounter rate(s) with the drop ratio. We show that the modeled drop ratio fits simulation results obtained with synthetic traces for both cases

The Design, Manufacturing, and Testing of an Undertray for Formula SAE

A student-built lap time simulation coupled with the scoring model of the Formula Society of Automotive Engineers (SAE) Series has revealed the major importance of downforce on overall points. As a result, the Global Formula Racing (GFR) team has recently focused much effort towards the development of an aerodynamics package for their Formula SAE racecars. One component of the aerodynamics package is the undertray, a device that exploits the underbody airflow to generate downforce. This thesis details the development of the undertray used for the 2013 GFR aerodynamics package, including the aerodynamic design, mechanical design, manufacturing, and physical validation. The 2013 undertray is a simple inverted airfoil concept inspired by the Lotus Type 78 F-1 car.Key Words: Aerodynamics Formula SAE Undertra

Deep penetrating nevus: a case report and brief literature review

BACKGROUND -: Deep penetrating nevus (DPN) is a distinct variant of melanocytic nevus and remains a histopathologic challenge to pathologists because of its resemblance to blue nevus, malignant melanoma, pigmented Spitz nevus, and congenital melanocytic nevus. It often goes unrecognized due to its relative rarity. CASE PRESENTATION -: Here we report a case of DPN of the left anterior leg in a 51-year old female. A brief review of the literature shows that these lesions have a distinct growth pattern and cellular morphology that can differentiate these lesions from other entities including malignant melanoma. CONCLUSION -: It is important to recognize these features because DPN carries a better prognosis than malignant melanoma

Characterization of small RNA populations in non-transgenic andaflatoxin-reducing-transformed peanut

Aflatoxin contamination is a major constraint in food production worldwide. In peanut (Arachis hypogaea L.), these toxic and carcinogenic aflatoxins are mainly produced by Aspergillus flavus Link and A. parasiticus Speare. The use of RNA interference (RNAi) is a promising method to reduce or prevent the accumula-tion of aflatoxin in peanut seed. In this study, we performed high-throughput sequencing of small RNApopulations in a control line and in two transformed peanut lines that expressed an inverted repeattargeting five genes involved in the aflatoxin-biosynthesis pathway and that showed up to 100% less aflatoxin B1 than the controls. The objective was to determine the putative involvement of the smallRNA populations in aflatoxin reduction. In total, 41 known microRNA (miRNA) families and many novel miRNAs were identified. Among those, 89 known and 10 novel miRNAs were differentially expressed in the transformed lines. We furthermore found two small interfering RNAs derived from the inverted repeat, and 39 sRNAs that mapped without mismatches to the genome of A. flavus and were present only in the transformed lines. This information will increase our understanding of the effectiveness of RNAi and enable the possible improvement of the RNAi technology for the control of aflatoxins

Perspective Chapter: Access to Rural Water and Sanitation Services in Cameroon within the Context of Sustainable Development Goals (SDGs)

This chapter examines the situation of rural water and sanitation services in Cameroon within the context of sustainable development goals (SDGs), to establish whether Cameroon is on right track of meeting the SDG, and proposes actions to be taken to achieve universal access for water and sanitation. Based on the analyzed data obtained from national surveys and the Joint Monitoring Program for 2021, it argues that Cameroon is unlikely to reach universal access to water and sanitation in rural area by 2030. Factors contributing to poor access to rural water and sanitation services include the poor application of the policy and legal framework, the poor coordination of interventions between the actors involved in the sector, the low financial viability of the sector, the low efficiency of expenditure related to water and sanitation, and the lack of human resources in the sector. The implementation of the policy and legal framework, the stability of the institutional framework, the reaffirmation of the major role of the State of the changed Ministry of water, and the collaboration of all the actors of the sector within the mechanisms provided for this purpose are of fundamental importance to achieve SDG 6.1 and 6.2 in Cameroon

The molecular epidemiology of HIV-1 envelope diversity during HIV-1 subtype C vertical transmission in Malawian mother???infant pairs

To study the relationship between HIV-1 subtype C genetic diversity and mother-to-child transmission and to determine if transmission of HIV-1C V1/V2 env variants occurs stochastically