Use of ontology in identifying missing artefact links

The techniques of requirement traceability have evolved over recent years. However, as much as they have contributed to the software engineering field, significant ambiguity remains in many software engineering processes. This paper reports on an investigation of requirement traceability artefacts, stakeholders, and SDLC development models. Data were collected to gather evidence of artefacts and their properties from previous studies. The aim was to find the missing link between artefacts and their relationship to one another, the stakeholders, and SDLC models. This paper undertakes the first phase of the main research project, which aims to develop a framework for guiding software developers to actively manage traceability. After inquiring into and examining previous research on this topic, the links between artefacts and their functions were identified. The analysis resulted in the development of a new model for requirement traceability, defined in the form of an ontology portraying the contributively relations between software artefacts using common properties with the aid of Protégé Software. This study thus provides an important insight into the future of the requirement artefacts relation, and thereby lays an important foundation towards increasing our understanding of their potential and limitations

Development of Sustained-Release Microbeads of Nifedipine and In vitro Characterization

Purpose: To formulate and evaluate sustained-release microbeads of nifedipine for prolonged delivery.Methods: Nifedipine microbeads were prepared using sodium alginate and pectin in different ratios by ionic-gelation method. The microbeads were evaluated for surface morphology and shape by scanning electron microscopy (SEM), micromeritic properties, microencapsulation efficiency and in vitro drug release. The microbeads were also assessed by Fourier Transform Infra-red Spectroscopy (FTIR) and differential scanning calorimetry (DSC) to determine drug-polymer interaction, if any.Results: FTIR and DSC results indicate absence of interaction between the drug and polymers used. Good rheological behavior was demonstrated with an angle of repose < 30º, and Carr’s index and Hausner’s ratio of < 10% and < 1.12, respectively Microbead size, yield and entrapment efficiency were in the range of 695 to 733 um, 69 to 75% and 54 to 63%,  respectively. SEM revealed that the microbeads were discrete, largely spherical and free-flowing. Higuchi model was the best fit for the dissolution data and followed non-Fickian diffusion mechanism.Conclusion: The microbead formulation would be suitable for sustained release of nifedipine.Keywords: Microbead, Nifedipine, Alginate, Ionic gelation, Pectin, Higuchi model, Non-Fickian diffusion

Swarm of UAVs for Network Management in 6G: A Technical Review

Fifth-generation (5G) cellular networks have led to the implementation of beyond 5G (B5G) networks, which are capable of incorporating autonomous services to swarm of unmanned aerial vehicles (UAVs). They provide capacity expansion strategies to address massive connectivity issues and guarantee ultra-high throughput and low latency, especially in extreme or emergency situations where network density, bandwidth, and traffic patterns fluctuate. On the one hand, 6G technology integrates AI/ML, IoT, and blockchain to establish ultra-reliable, intelligent, secure, and ubiquitous UAV networks. 6G networks, on the other hand, rely on new enabling technologies such as air interface and transmission technologies, as well as a unique network design, posing new challenges for the swarm of UAVs. Keeping these challenges in mind, this article focuses on the security and privacy, intelligence, and energy-efficiency issues faced by swarms of UAVs operating in 6G mobile networks. In this state-of-the-art review, we integrated blockchain and AI/ML with UAV networks utilizing the 6G ecosystem. The key findings are then presented, and potential research challenges are identified. We conclude the review by shedding light on future research in this emerging field of research.Comment: 19,

Cross Sectional Study and Risk Factors Analysis of Francisella tularensis in Soil Samples in Punjab Province of Pakistan

Tularemia is an endemic zoonotic disease in many parts of the world including Asia. A cross-sectional study was conducted to determine genome-based prevalence of Francisella tularensis (Ft) in soil, assess an association between its occurrence in soil and likely predictors i.e., macro and micro-nutrients and several categorical variables, and determine seroconversion in small and large ruminants. The study included a total of 2,280 soil samples representing 456 villages in eight districts of the Punjab Province of Pakistan followed by an analysis of serum antibodies in 707 ruminants. The genome of Ft was detected in 3.25% (n = 74, 95% CI: 2.60–4.06) of soil samples. Soluble salts (OR: 1.276, 95% CI: 1.043–1.562, p = 0.015), Ni (OR: 2.910, 95%CI: 0.795–10.644, p = 0.106), Mn (OR:0.733, 95% CI:0.565–0.951, p = 0.019), Zn (OR: 4.922, 95% CI:0.929–26.064, p = 0.061) and nutrients clustered together as PC-1 (OR: 4.76, 95% CI: 2.37–9.54, p = 0.000) and PC-3 (OR: 0.357, 95% CI: 0.640, p = 0.001) were found to have a positive association for the presence of Ft in soil. The odds of occurrence of Ft DNA in soil were higher at locations close to a water source, including canals, streams or drains, [χ2 = 6.7, OR = 1.19, 95% CI:1.05–3.09, p = 0.004] as well as places where animals were present [χ2 = 4.09, OR = 2.06, 95% CI: 1.05–4.05, p = 0.02]. The seroconversion was detected in 6.22% (n = 44, 95% CI: 4.67–8.25) of domestic animals. An occurrence of Ft over a wide geographical region indicates its expansion to enzootic range, and demonstrates the need for further investigation among potential disease reservoirs and at-risk populations, such as farmers and veterinarians

In vitro Evaluation of Nateglinide-Loaded Microspheres Formulated with Biodegradable Polymers

Purpose: To formulate and evaluate sustained release microspheres of nateglinide (NTG) for enhanced patient compliance.Methods: Nateglinide microspheres were prepared with varying proportions of biodegradable polymers (olibanum gum and guar gum) by calcium chloride/sodium alginate ionic gelation method. The microspheres were characterized by micromeritic analysis, particle size analysis, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and in vitro drug release studies. Yield and encapsulation efficiency were also evaluated while drug release data were subjected to various kinetic models.Results: Micromeritic analysis showed good flow properties of the microspheres while yield and microsphere size were in the range of 70 to 80 % and 781 to 842 μm, respectively. FTIR and DSC results indicate the absence of drug-polymer interactions while SEM revealed that microspheres were almost spherical shape and porous in nature. Drug release was sustained in simulated intestinal fluid (pH 7.2), extending up to 10 to 12 h with greater release retardation in microspheres containing olibanum gum. The release pattern followed Higuchi kinetics model with non-Fickian diffusion.Conclusion: Suitable microspheres for sustained release of nateglinide can be formulated by ionic gelation method.Keywords: Nateglinide, Microspheres, Micromeritics, Drug release, Ionic gelation, Olibanum gum, Guar gu

Effect of A and B-site substitution with Pb, La and Ti on phase stabilization and multiferroic properties of BiFeO3

Abstract The work presents a comparative study of the effects of divalent (Pb), trivalent (La) and tetravalent (Ti) substituents on the multiferroic properties of BiFeO3 (BFO). Both A and B-sites were substituted to obtain the compositions i.e. (Bi1−x−yLaxPby)(Fe1−zTiz)O3 (x, y = 0, 0.1, 0.2 and z = 0, 0.05, 0.1, 0.15). Each of the substituent was particularly chosen i.e. Pb was chosen to keep the lone pair character which is the similar case as Bi ion. Additionally isovalent La was chosen to achieve single phase by reducing Bi volatization. Both these ions, on substitution, stabilized the crystal structure and suppressed the formation of extra phases which are unavoidable in pure BFO. All the Ti substituted and Bi0.8La0.2FeO3 compositions exhibited rhombohedral perovskite (R3c) phase, while Bi0.8Pb0.2FeO3 and Bi0.8La0.1Pb0.1FeO3 exhibited cubic phase. Mössbauer measurements revealed that impurity phase in case of compositions with divalent and trivalent substituents, disappeared completely when Ti substituted Fe. For all the compositions Fe ions were found in +3 state. High temperature dielectric properties showed that all the compositions were ferroelectric with paraelectric transition lying well above the room temperature. Weak ferromagnetism was found in Ti substituted compositions where coercivity was found to increase as the Ti concentration increases. All the BFO samples substituted with Pb, exhibited a dielectric anomaly in the temperature range, 100 °C ⩽ T ⩽ 250 °C. A systematic reduction in the intensity of the dielectric anomaly peak was observed as a function of Ti concentration which indicates that the anomaly is related to the conductivity and is element specific. However, Mössbauer data revealed absence of Fe2+ state, which ensured that it was not related with the presence of Fe2+ ions. Saturation polarization was found to increase as Ti concentration increased from 0% to 10%

Solution processing of morphotropic phase boundary BiFeO3-PbTiO3 thin films with reduced conductivity for high room temperature switchable polarization

[EN] The (1 – x)BiFeO-xPbTiO (BFO-PTO) perovskite solid solution has great potential for being used in practical devices, as it exhibits significant ferroelectric response at its morphotropic phase boundary (MPB). However, the significant conduction, particularly high electrical leakage currents that BFO-PTO films show at room temperature, deteriorates their functionality. This is mainly associated with the presence of multivalent iron along with A-site and oxygen vacancies. Here, solution-derived BFO-PTO thin films have been crystallized at low temperature on Pt/TiO/SiO/Si substrates, by a rapid thermal annealing process to minimize Bi and Pb volatilization. X-ray analyses have revealed that textured films are obtained with a pseudocubic perovskite structure and without the formation of detectable second phases. Microstructural studies indicated a columnar growth of the films with grain size well above the nanometric range, which, therefore, should not produce an appreciable reduction of the ferroelectric response due to size effects. Because of the relatively low content of charged defects produced in these BFO-PTO films during processing, ferroelectric hysteresis loops can be measured at room temperature. The highest value of remnant polarizations (2P= 58 μC/cm) was obtained for the 0.65BiFeO-0.35PbTiO (65BFO-35PTO) films, which suggests that this film composition lies in the proximity of the MPB where the coexistence of a highly textured  tetragonal phase and a rhombohedral one seems to occur.Layiq Zia acknowledges the Higher Education Commission of Pakistan (HEC) for financial support for his stay at ICMM-CSIC under the Indigenous 5000-PhD Fellowship Program (PIN: 112-27186-2PS1-143) and the International Research Support Initiative Program (IRSIP) (PIN: IRSIP 43 PSc 48). Ricardo Jiménez, Iñigo Bretos, Harvey Amorín, Miguel Algueró, and M. Lourdes Calzada acknowledge the financial support of the Spanish Projects PID2019-104732RB-I00, MAT2017-88788-R, and MAT2017-91772-EXP. Iñigo Bretos acknowledges financial support from the Ramón & Cajal Spanish Program. GHJ acknowledges financial support from the Pakistan Higher Education Commission (HEC, NRPU project number 8342). Enrique Rodríguez-Castellón thanks project RTI2018-099668-BC22 of Ministerio de Ciencia, Innovación y Universidades, and FEDER funds

Parametric Classification of Furniture From Point Cloud Developed Using Low Cost Trolley Based Laser Scanning System

This paper presents a parametric classification methodology to identify common indoor and outdoor furniture objects present in the 3D Cartesian point cloud of the surveyed environment. For this purpose, a low cost custom made trolley based scanning and surveying system has developed using orthogonal integration of two popular Hokuyo-30LX 2D laser scanners. The developed system has been successfully used to generate 3D point cloud of the environment using Simultaneous Localization and Mapping (SLAM) technique. The instrumentation system of the trolley has been interfaced through Robot Operating System (ROS) for online processing and recording of all sensorial data. While classification of the furniture present in point cloud has been done in offline mode using Random Sampling and Consensus (RANSAC) based parametric segmentation technique. The innovative furniture detection has applied on each scan in order to reduce the region of interest in the developed point cloud. In addition, the validation of the classified furniture objects has been performed using Fuzzy Logic. Multiple indoor and outdoor vicinities have been scanned and modelling results have been found accurate nearer to ground truth. In comparison to available surveying solutions present in the local market, the developed system has been found faster and precise to produce more enhanced structural results with minute details