19 research outputs found
CFD INVESTIGATION OF PLATE HEAT EXCHANGER USING NANOFLUIDS
Heat transfer and fluid flow in a single pass counter flow chevron corrugated-plates plate heat exchanger considering nanofluids (SiO2 and CuO) as homogeneous mixtures has been presented in this dissertation using the Commercial CFD software, ANSYS FLUENT. The required thermo physical properties of the nanofluid have been taken from literature and used in CFD Model. Individual optimum concentration of SiO2/water and CuO/water nanofluids yields maximum heat transfer improvement with regards to the temperature, pressure and velocity fields. The results of CFD analysis of CuO and SiO2 were compared with Common fluid Water in order to verify the accuracy of the homogeneous model. Analysis can be performed to predict the plate heat exchanger performance with reasonable accuracy. SiO2/water gives better heat transfer performance compared to CuO/water. CFD Analysis shows that corrugation pattern of the plate develops turbulence and vortices of fluid which results in high heat transfer rates
Application of machine learning with impedance based techniques for structural health monitoring of civil infrastructure
Increased attentiveness on the environmental and
effects of aging, deterioration and extreme events on civil
infrastructure has created the need for more advanced damage
detection tools and structural health monitoring (SHM). Today,
these tasks are performed by signal processing, visual inspection
techniques along with traditional well known impedance based
health monitoring EMI technique. New research areas have been
explored that improves damage detection at incipient stage and
when the damage is substantial. Addressing these issues at early
age prevents catastrophe situation for the safety of human lives.
To improve the existing damage detection newly developed
techniques in conjugation with EMI innovative new sensors,
signal processing and soft computing techniques are discussed in
details this paper. The advanced techniques (soft computing,
signal processing, visual based, embedded IOT) are employed as
a global method in prediction, to identify, locate, optimize, the
damage area and deterioration. The amount and severity,
multiple cracks on civil infrastructure like concrete and RC
structures (beams and bridges) using above techniques along
with EMI technique and use of PZT transducer.
In addition to survey advanced innovative signal processing,
machine learning techniques civil infrastructure connected to
IOT that can make infrastructure smart and increases its
efficiency that is aimed at socioeconomic, environmental and
sustainable development
MicroRNA-210-mediated proliferation, survival, and angiogenesis promote cardiac repair post myocardial infarction in rodents
The final publication is available at Springer via http://dx.doi.org/10.1007/s00109-017-1591-8.An innovative approach for cardiac regeneration following injury is to induce endogenous cardiomyocyte (CM) cell cycle re-entry. In the present study, CMs from adult rat hearts were isolated and transfected with cel-miR-67 (control) and rno-miR-210. A significant increase in CM proliferation and mono-nucleation were observed in miR-210 group, in addition to a reduction in CM size, multi-nucleation, and cell death. When compared to control, ฮฒ-catenin and Bcl-2 were upregulated while APC (adenomatous polyposis coli), p16, and caspase-3 were downregulated in miR-210 group. In silico analysis predicted cell cycle inhibitor, APC, as a direct target of miR-210 in rodents. Moreover, compared to control, a significant increase in CM survival and proliferation were observed with siRNA-mediated inhibition of APC. Furthermore, miR-210 overexpressing C57BL/6 mice (210-TG) were used for short-term ischemia/reperfusion study, revealing smaller cell size, increased mono-nucleation, decreased multi-nucleation, and increased CM proliferation in 210-TG hearts in contrast to wild-type (NTG). Likewise, myocardial infarction (MI) was created in adult mice, echocardiography was performed, and the hearts were harvested for immunohistochemistry and molecular studies. Compared to NTG, 210-TG hearts showed a significant increase in CM proliferation, reduced apoptosis, upregulated angiogenesis, reduced infarct size, and overall improvement in cardiac function following MI. ฮฒ-catenin, Bcl-2, and VEGF (vascular endothelial growth factor) were upregulated while APC, p16, and caspase-3 were downregulated in 210-TG hearts. Overall, constitutive overexpression of miR-210 rescues heart function following cardiac injury in adult mice via promoting CM proliferation, cell survival, and angiogenesis
Virtual prototype-based kinematic modeling and simulation of a multi-mode amphibious robot
The amphibious robot, which has the capability of multi-mode motion, can maneuver diverse environments with high mobility and adaptability. These are employed in the area of reconnaissance, search and rescue operations, and monitoring. The existing amphibious robots have lower maneuverability over the crawling period on uneven and slope surfaces on the land. In this paper, a kinematic model of the amphibious robot based on virtual prototyping is designed for multi-mode locomotion. ADAMS (Automated dynamic analysis of mechanical systems) is a multi-body dynamic solver adopted to build the simulation model for the robot. The novel amphibious robot employs a Rockerbogie mechanism equipped with wheel paddles. The locomotion analysis on land involves straight-going and obstacle negotiation, which is simulated using ADAMS. The simulation analysis result demonstrates increased maneuverability, achieving a robot's velocity of robot 1.6 m/s. Normal forces on the front and rear wheels show equal load distribution, contributing more to the robotโs equilibrium over uneven terrain. The simulation result reflects the accurate kinematic characteristics of the amphibious robot and provides a theoretical basis for developing an algorithm for robot motion control and optimization. Further, this research will concentrate on the kinematic simulation maneuvering in water mode with the wheel paddle
Locomation strategies for amphibious robots-a review
In the past two decades, unmanned amphibious robots have proven the most promising and efficient systems ranging from scientific, military, and commercial applications. The applications like monitoring, surveillance, reconnaissance, and military combat operations require platforms to maneuver on challenging, complex, rugged terrains and diverse environments. The recent technological advancements and development in aquatic robotics and mobile robotics have facilitated a more agile, robust, and efficient amphibious robots maneuvering in multiple environments and various terrain profiles. Amphibious robot
locomotion inspired by nature, such as amphibians, offers augmented flexibility, improved adaptability, and
higher mobility over terrestrial, aquatic, and aerial mediums. In this review, amphibious robots' locomotion
mechanism designed and developed previously are consolidated, systematically The review also analyzes
the literature on amphibious robot highlighting the limitations, open research areas, recent key development
in this research field. Further development and contributions to amphibious robot locomotion, actuation, and
control can be utilized to perform specific missions in sophisticated environments, where tasks are unsafe
or hardly feasible for the divers or traditional aquatic and terrestrial robots
Characterisation of fasted state gastric and intestinal fluids collected from children
Fundamental knowledge about the composition of intestinal fluids in paediatric populations is currently unavailable. This study aimed to characterise gastric and intestinal fluid from paediatric populations. Gastric and intestinal fluid samples were obtained during routine clinical endoscopy from paediatric patients at a large teaching hospital. These fluids were characterised to measure the pH; buffer capacity; osmolality; bile acid concentration and composition. A total of 55 children were recruited to the study aged from 11 months to 15 years of age where 53 gastric fluid samples and 40 intestinal fluid samples were obtained. pH values recorded ranged from pH 0.57 to 11.05 (median: 2.50) in gastric fluids and from 0.89 to 8.97 (median: 3.27) in intestinal fluids. The buffer capacity did not change significantly between gastric and intestinal fluids with median values of 12 mM/L/ฮpH for both fluids. Gastric fluid osmolality values ranged from 1 to 615 mOsm/kg, while intestinal fluid values ranged from 35 to 631 mOsm/kg. Gastric fluid bile acid concentrations ranged from 0.002 to 2.3 mM with a median value of 0.017 mM whilst intestinal fluid bile acid concentrations ranged from 0.0008 to 3.3 mM with a median value of 0.178 mM. Glycocholate; taurocholic acid; glycochenodeoxycholate and taurochenodeoxycholate were the most commonly identified bile acids within paediatric intestinal fluids. All compositional components were associated with large inter-individual variability. Further work is required to develop simulated paediatric media and to explore the impact of these media on drug solubility and dissolution
COVID-19 Vaccination Among Diverse Population Groups in the Northern Governorates of Iraq
Objectives: The present study was carried out to investigate COVID-19 vaccination coverage among populations of internally displaced persons (IDPs), refugees, and host communities in northern Iraq and the related underlying factors.Methods: Through a cross-sectional study conducted in five governorates in AprilโMay 2022, 4,564 individuals were surveyed. Data were collected through an adapted questionnaire designed to gather data on participants.Results: 4,564 subjects were included (59.55% were 19โ45ย years old; 54.51% male). 50.48% of the participants (51.49% of host communities, 48.83% of IDPs, and 45.87% of refugees) had been vaccinated with at least one dose of COVID-19 vaccine. 40.84% of participants (42.28% of host communities, 35.75% of IDPs, and 36.14% of refugees) had been vaccinated by two doses, and 1.56% (1.65% of host communities, 0.93% of IDPs, and 1.46% of refugees) were vaccinated with three doses.Conclusion: Sociodemographic factors including age, gender, education, occupation, and nationality could affect vaccination coverage. Moreover, higher acceptance rate of vaccination is associated with belief in vaccine safety and effectiveness and trust in the ability of the vaccine to prevent complications
Occurrence of indoor insect pests and illnesses of inhabitants in Malappuram, Kerala, India
Indoor insect pests have a direct and negative impact on human health by inflicting bites and stings, causing allergic reactions and transmitting diseases. Certain volatile and non-volatile organic compounds, secreted by indoor insect pests, are important components of indoor air quality. Volatile compounds have been associated with numerous health disorders. In this study, we used a questionnaire-based approach to quantify the insect populations from 403 indoor spaces along with the features of the indoor systems and the symptoms observed by the inhabitants. We recorded surrounding environmental variables, biological contaminants and possible reasons that the inhabitants thought were behind the increase in the number of certain pests. The indoor environment was the second most common reason attributed to the occurrence of indoor illness, likely due to the pandemic. We also found a significant relation between the indoor biological contaminants recorded and the increasing number of illnesses. Although insects were considered a nuisance in many households, they were not found to be directly related to higher numbers of ill inhabitants. Nonetheless, the increasing number of patients with allergies in the past few years and the increasing health issues reported from indoor spaces with higher pest populations indicates their potential impact
Locomotion performance of amphibious robot vehicle using transformable rocker-bogie mechanism
exploring amphibious robots owing to their excellent locomotion capabilities in diverse environments. An
amphibious robot needs locomotion to maneuver on irregular, uneven terrains on land and a dynamic water medium. The study presents an amphibious robot that employs a rocker-bogie mechanism with an adjustable link providing retractable and unretractable configuration suitable on terrestrial and aquatic mediums. This paper proposes an amphibious robot vehicle (ARV) unretractable mode suitable for inclined locomotion on uneven land surface and retracted mode suitable for locomotion on water. Experiment investigation demonstrates Cross hill and downhill Grade ability on inclined surfaces that stabilize the ARV preventing it from slippage and flip over. The trainability and adaptability on land. The Simulation in Ansys for flow velocity vector shows retractable wheel position significantly improves trust forces by reducing the low bow losses. An integrated paddle mechanism will be employed in future design to increase the mobility on the Water Wheel