FEA Modelling of Weld-deposition based Additive Manufacturing for the Residual Stress Prediction

Research in the development of additive manufacturing process employing direct metal deposition for the fabrication of fully functional parts and tooling has generated significant interest in the recent years. Three-dimensional welding is being investigated as an additive manufacturing technique for the production of real metallic parts using gas metal arc welding (GMAW) principles. The temperature field distribution during weld based rapid prototyping induces complex thermal stress evolutions and plays a big role in residual stress distributions. The present work is to investigate the temperature field and thermal stress distributions in the multi-pass single-layer weld-deposition based additive manufacturing using twin wire welding. A three-dimensional finite element model with the temperature-dependent material properties and moving heat source is modelled for the same. A double ellipsoidal heat source model is applied to calculate the twin wire welding‟s temperature field is used. The filler metal deposition is taken into account by implementing the birth-and-death functionality for the finite elements. The temperature distribution pattern and magnitude is subsequently obtained. This result is then used for estimation of residual stress and distortion due to the twin wire welding

Pengembangan Probe Sensor Kelembaban Serat Optik Dengan Cladding Gelatin

Development of Fiber-Optic Humidity Sensor Probe with Gelatin Cladding. Humidity sensor based on optical fiberwith gelatin cladding has been developed. In this humidity sensor probe, the origin cladding of optical fiber is replacedby gelatin coating as humidity sensitive cladding. Testing of the optical fiber sensor probe was conducted by measuringof light intensity transmitted on the optical fiber probe for each variation of different humidity treatments. Response ofthe optical fiber sensor probe measured from 42%RH to 99%RH, the results show an optical transmission curve variedwith relative humidity (RH). Optical transmission in the optical fiber probe increase with RH value at a specificwavelength range, that is from green to red spectrum bands (500 nm - 700 nm), where a significant variation from 600nm to 650 nm in yellow to red spectrum bands. Wavelength where is a maximum intensity of optical transmissionoccurs at 610 nm. Therefore, the optical fiber humidity sensor probe could response humidity form 42%RH to 99%RHwith the best response in humidity range of 60%RH to 72%RH that is have a good linearity and sensitivity

Efficient design for smart environment using Raspberry Pi with Blockchain and IoT (BRIoT)

Internet of Things (IoT) is reshaping digital world day by day by integrating several technologies to provide smart services. However, intrinsic features of IoT resulting in a number of challenges, such as decentralization, poor interoperability, privacy, confidentiality, and security vulnerabilities. Several security techniques like encryption, third-party software’s are in use currently to protect users data. Blockchain was initially established for digital crypto currencies with a Proof of Work (PoW) consensus process and the advantage of smart contracts, which enabled distributed trust without the involvement of a third party. Its distributed trust concept paved the way for many other developments, such as the development of new consensus mechanisms such as Proof of Stake (PoS) and Proof of Authority (PoA), which aided in the adoption of Blockchain with low computation machines into sectors such as smart industry and smart transportation. Blockchain implementation in IoT can address the security issue, here we proposed a design using Raspberry Pi as edge node (BRIoT)

Mathematical Modelling and Analysis of Memristors with and without its Temperature Effects

In this paper the main goal is to study the principle structure and characteristics of single and multiple memristors and also the temperature effects. The complete analysis described here is done by using matlab Simulink. The relationship between the on resistance, off resistance and ionic mobility with respect to temperature has been analyzed and shown graphically. The memristor can be used as a High speed switch and it can be used in non volatile computer memories due to its higher switching speeds

Mathematical Modelling and Analysis of Memristors with and without its Temperature Effects

In this paper the main goal is to study the principle structure and characteristics of single and multiple memristors and also the temperature effects. The complete analysis described here is done by using matlab Simulink. The relationship between the on resistance, off resistance and ionic mobility with respect to temperature has been analyzed and shown graphically. The memristor can be used as a High speed switch and it can be used in non volatile computer memories due to its higher switching speeds

Parallel Discrete Convolutions on Adaptive Particle Representations of Images.

We present data structures and algorithms for native implementations of discrete convolution operators over Adaptive Particle Representations (APR) of images on parallel computer architectures. The APR is a content-adaptive image representation that locally adapts the sampling resolution to the image signal. It has been developed as an alternative to pixel representations for large, sparse images as they typically occur in fluorescence microscopy. It has been shown to reduce the memory and runtime costs of storing, visualizing, and processing such images. This, however, requires that image processing natively operates on APRs, without intermediately reverting to pixels. Designing efficient and scalable APR-native image processing primitives, however, is complicated by the APR's irregular memory structure. Here, we provide the algorithmic building blocks required to efficiently and natively process APR images using a wide range of algorithms that can be formulated in terms of discrete convolutions. We show that APR convolution naturally leads to scale-adaptive algorithms that efficiently parallelize on multi-core CPU and GPU architectures. We quantify the speedups in comparison to pixel-based algorithms and convolutions on evenly sampled data. We achieve pixel-equivalent throughputs of up to 1TB/s on a single Nvidia GeForce RTX 2080 gaming GPU, requiring up to two orders of magnitude less memory than a pixel-based implementation

Incidental findings detected on abdomino-pelvic multidetector computed tomography performed in the acute setting.

OBJECTIVE: The objective of the study is to determine the prevalence and significance of incidental findings in patients with a chief complaint of abdominal pain presenting to the emergency department (ED) who received abdomino-pelvic multidetector computed tomography. MATERIALS AND METHODS: We conducted a retrospective review of data collected for 290 patients over a period of 5 months (April to September 2012) from 3 different university-affiliated EDs. Two board-certified radiologists reviewed the original images independently and recorded the incidental findings. These findings were classified as benign, indeterminate, and worrisome. Only those findings present in the original report were included in the study. If an indeterminate or worrisome incidental finding was identified, the patient\u27s medical records were reviewed to determine if the incidental finding was previously known, whether recommendation was made for further evaluation, and whether this recommendation led to any change in management. RESULTS: We identified 283 incidental findings—144 benign (51%), 114 indeterminate (40%), and 25 worrisome (9%) findings. A statistically significant difference was observed in the percentage of patients who experienced a change in management among those who received recommendations as compared with those who did not, in both previously known (87% vs 22%, P=.001) and previously unknown (70% vs 2%, P=.001) indeterminate findings. CONCLUSION: Unlike benign incidental findings, indeterminate and worrisome findings frequently alter the course of management. Recommendation from radiologists appears to significantly contribute to the management of indeterminate incidental findings

Simulasi Distribusi Suhu pada Lubang Tanam Hidroponik Rakit Apung untuk Produksi Bawang Merah di Dataran Rendah Tropika

This paper discusses the cooling effect of the root zone (the root zone cooling) at a floating hydroponic for the shallot production in tropical lowland by cooling the nutrient bath. The study was conducted at three different temperatures, i.e. low temperatures (8-10OC), medium temperature (13-15OC), and control (23-26OC) with variable responses that include wet weight, dry weight, number of bulbs and weight per bulb. Plant growth responses were analyzed using statistical methods Fisher's least significant difference (LSD), while the temperature distribution on a floating hydroponic was analyzed by computational fluid dynamics (CFD) simulation approach. CFD simulation approach was able to describe the temperature distribution on a floating hydroponic well, where the coefficients of determination (R2) for each treatment of low temperature, medium and controls are 0.983, 0.980 and 0.862 respectively. The results showed that the number of bulbs was the most responsive variable, where the induction of bulb formation at low temperature is more than 200% of the control temperature and more than 60% of the medium temperature