Physical Sciences and Engineering

The evaluation of the material strength of concrete over time is a significant concern in many civil engineering construction projects. Several reference documents, including BAEL 91, provide formulas to estimate the compressive strength of concrete at J days based on the strength measurements obtained at 7 days. However, noticeable differences exist between the estimated values and the actual values obtained during construction when applying these formulas.

The routing protocol of nodes in RPL networks will now use a safe blockchain-based authentication system, according to this study. The Ethereum blockchain and smart contracts are used in the suggested approach to address the security issues, notably Decreased Rank At-tack in RPL network topology. The background of RPL, IoT-LLNs, and blockchain technology is covered in the study, along with the suggested methodology and its application. The study also assesses the performance of the suggested remedy and contrasts it with current approaches.

Biometric authentication is now widely utilised as an alterna-tive to passwords on IoT devices such as smartphones. However, present biometric systems are subject to spoofing attacks. Several liveness detec-tion techniques have been presented to determine whether a live person or an artificial duplicate is in front of the biometric sensor. However, the challenge remains unsolved due to the difficulty in identifying discrimina-tive and computationally affordable traits for spoofing attacks.

Les échanges des biens et services constituent le dénominateur des activités socio-économiques pour les Etats. Ainsi donc le commerce international des produits de base est l’un des échanges que fait de la République Démocratique du Congoavec les autres Etats Membres de l’Organisation Mondiale du Commerce. Sans peur d’être contredit, tout est démontré dans cet article que le négoce des produits de base de la RDC demeure défavorable pour le développement durable de la population congolaise. Face à cela, la thèse de la malédiction des matières premières est amplement confirmée.

The construction of infrastructure capable of withstanding future hazards in the Akpakpa district requires good control of the foundation soils. The test results showed that the Ayélawadjè and Sodjèatimey soils are class D according to the GTR classification and sub-class D1 (VBS<0. 1): insensitive to water, weakly organic and presenting an over-consolidated state, while the Avotrou soils are of class A according to the GTR classification and of sub-class A4 (IP>40%): very plastic with the following main characteristics: very coherent and almost impermeable.

The Bongor region, located between 10°12' and 10°20' North latitude and 15°22' and 15°34' East longitude, is part of the quaternary aquifers of Chad. It has potential in water resources but knowledge of its hydrodynamic and hydrogeochemical functioning remains insufficient. Thus, this study aims to gain knowledge of the hydrogeochemistry of groundwater in the Bongor area and its surroundings.

Railway incidents can have significant safety implications for the railway system, its components, and people involved, leading to train delays and financial losses. Railway forensic investigations play a crucial role in understanding the causes and circumstances of these accidents. This field is continuously evolving and offers scope for improvement. Various organizations are responsible for conducting thorough railway examinations, highlighting the importance of their expertise in investigations. Examining rolling stock is essential for analyzing train condition and performance.

The stability of the bcc non-magnetic (NM) state in Vanadium (V) and the optical properties are investigated, using the full-potential linearized augmented plane wave (FP-LAPW) method with the generalized gradient approximation (GGA) and GGA+U within the framework of density functional theory (DFT), as implemented in the WIEN2k computational package code. As compared to other 3d transition metals such as Fe, Co, and Ni, the non-magnetic state of bcc V has been found to be distinct from that seen in previous studies.

Background: Down syndrome is characterized by general mental and physical disorders, or by isolated walking, cognitive, growth, or sensory disorders. Objective: The study examined the impact of an integrated sensory approach on the improvement of balance and motor coordination in children suffering from Down syndrome. Methods: Thirty children were randomly divided into two categories: group A received a combination of sensory integration and physical therapy, Group B received only the physiotherapy program.

The compound oxazole and its derivatives are crucial to the field of medical chemistry. The oxazole nucleus is a heterocyclic five-membered ring that has been explored in an effort to develop new molecules with advantageous biological properties. In recent years, the use of oxazole as intermediates in the synthesis of novel chemical entities in medical chemistry has risen. Oxazole has sporadically been used as a functional lead molecule in contemporary pharmaceutical chemistry.