Heat transfer in water with the help of solar energy is an effective way to harness renewable energy and reduce reliance on non-renewable sources of energy. The utilization of turbulent promoters is an efficient solution to ameliorate the performance of heat exchangers (HE). The current work summarizes the experimental and numerical behaviour of HE reported in the literature, including the thermal examinations of HT and fluid flow characteristics with various turbulent promoters and tube arrangements. This article reviews multiple studies in which different twisted tape (TT) geometry enhances the HT rate in various HE tubes. The current work also compares the thermal performance (η) of TT configurations in HE tubes using correlations developed by different investigators. Maximum heat transfer and minimum friction factor concerning fluid utilized in the system may also produce the optimal form for twisted tapes.
This paper explores the development and application of the incremental forming process, an innovative method for manufacturing complex parts with high flexibility and low tooling costs. The review categorizes three key process variants: Single Point Incremental Forming (SPIF), Two Point Incremental Forming (TPIF), and Incremental Forming with Conjugated Active Plate (IFCAP). This study demonstrates the significant effects of these process variants on part accuracy and material behavior, particularly under varying process conditions. This study identifies critical technological parameters such as tool diameter, feed rate, and vertical step size. The findings also demonstrate the role of optimized toolpaths and lubrication in improving process efficiency. Applications of incremental forming across various industries, including automotive, aerospace, medical, and construction, demonstrate its versatility in prototype production and small-series manufacturing. These results contribute to a deeper understanding of incremental forming, offering practical recommendations to enhance precision, scalability, and material formability, and supporting future innovations and broader industrial applications.
Ti6Al4V titanium alloy is considered a biocompatible material, suitable to be used for manufacturing medical devices, particularly cranioplasty plates. Several methods for processing titanium alloys are reported in the literature, each one presenting both advantages and drawbacks. A decision-making method based upon AHP (analytic hierarchy process) was used in this paper for choosing the most recommended manufacturing process among some alternatives. The result of AHP indicated that single-point incremental forming (SPIF) at room temperature could be considered the best approach when manufacturing medical devices. However, Ti6Al4V titanium alloy is known as a low-plasticity material when subjected to plastic deformation at room temperature, so special measures had to be taken. The experimental results of processing parts from Ti6Al4V titanium alloy by means of SPIF and technological aspects are considered.
Open spina bifida, also known as spina bifida aperta is a neural tube defect involving the lack of closure of vertebral arches and associated meninges and/or spinal cord abnormalities.Ultrasound examination is the gold standard for the diagnosis of spina bifida aperta. It represents the main imaging tool used to ascertain this diagnosis early in gestation. Three-dimensional ultrasound is necessary to detect the level and the size of the defect. Magnetic resonance imaging (MRI) represents a more sensitive tool, giving specific information of the defect and associated anomalies, playing an important role in ruling out differential diagnosis. Due to the advent of MRI use, it is possible today to achieve in utero treatment of fetuses with this pathology. The aim of the current review is to provide an update of literature regarding the role of ultrasound and MRI in the prenatal diagnosis of spina bifida aperta.
Pentalogy of Cantrell (POC) is a rare condition characterized by complete or partial expression of 5 types of congenital birth defects originating in (1) the lower sternum, (2) the anterior diaphragm, (3) the diaphragmatic pericardium, (4) the midline/ventral supraumbilical abdominal wall region, and (5) the heart. POC can be diagnosed antenatally by means of ultrasonography (US), the task being difficult if defects are minor. Advances in the field of US and the introduction of the first morphology trimester as state-of-the-art pregnancy monitoring, facilitate the early diagnosis of this condition. We performed a systematic review on 67 reported cases of POC diagnosed in the first trimester of pregnancy (published from January 1980 to July 2019). The aim of our systematic review was twofold: to assess the main US findings in the first trimester of pregnancy and to increase awareness of early diagnostic possibilities. Our study showed that POC can be diagnosed in the first trimesterof pregnancy based on key US findings such as the association between omphalocele and ectopia cordis. When these two anomalies are present, increased nuchal translucency can also be considered a marker of POC in the first trimester.
This article describes a method for the real-time monitoring of the current consumed by a Dynamixel MX 64 AT servomotor used in the actuation system of modular mobile robotic platforms having differential locomotion and conventional wheels. The data acquisition method is based on an Arduino Mega 2560 development board interfaced with Matlab Simulink and the ASC712-5A hall sensor for current detection. A Simulink model is presented that performs the detection of a sensor reference voltage, which needs to be calibrated for a correct reading of the current. Due to the low resolution of the analog-to-digital converter with which the Arduino Mega is equipped, current monitoring is difficult to achieve, having large fluctuations and a lower resolution than the current absorbed by the servomotor. The solution to this problem is achieved by implementing, in the hardware construction, an ADS115 conversion module with 16-bit resolution, which leads to an increase in the measurement range of the ASC712-5A sensor. The current acquisition model with the Hall sensor is experimentally validated using measurements on the physical model of the drive wheel. This article further deals with the CAD and digital block modeling of mobile platforms with four and two wheels. The dynamic model of the robot is created in the Simulink–Simscape–Multibody environment and is used to determine the servomotor torques when the robot is moving along the predefined path. The torque variations are entered as variables in the Simulink digital block model of the robot. The Simulink model is simulated when moving along a square path, which determines the variation in the current absorbed by the motors. Experimental validation of the model is carried out using measurements on the functional models that operate in real conditions. A power consumption method is further proposed.