bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficacy of Volume of Fluid Method in Computational Simulation of Sloshing Phenomenon
Authors: Joshi Aditya Y. , Saikia Pranaynil , Rakshit Dibakar
Published: May 2021

The present study deals with the analysis of stochastic transient pressure variations and wall impacts for scaled down models of LNG carriers by using the VOF technique for interface characterization. Numerical simulation of sloshing under sway using multiphase liquid-gas condition has been carried out. Use of VOF method for multiphase numerical simulation is compared with the results of previously performed SPH study and established sloshing experiments. The efficacies of the VOF interface capturing technique is established by comparison with high-resolution images taken during sloshing experiments performed under the same external excitation frequency, amplitude and fill level. The pressure data from experiments when compared with respective simulations involving SPH and VOF methods helps to capture the fluid flow behaviour and intricacies they can handle.
Analysis of Elliptical Wing Type Bird Inspired Device
Authors: Kumar M H , Dorlikar P
Published: May 2021

Technology advancements have made the use of Unmanned Aerial Vehicles (UAV) in many applications. This paper aims at performing stress analysis of elliptical wing type birds using ABAQUS. The wings considered for investigation are elliptical wings of two birds having low aspect ratio. Aerodynamic forces like lift and drag are calculated and applied on proposed wing design CAD models to obtain results of stresses and structural deformation at different altitude. The material used for wing structure is carbon fiber for its various advantages over other materials. Further, shape optimization of wing structure has performed to reduce the stresses at critical regions and to reduce volume of material. This wing design analysis helps designers to build UAV in optimizing manner. In addition to above investigation, various flapping wing mechanisms 2D in SAM and 3D in ADAMS have made based on curves that are obtained by tracing the tip of wings of selected birds in TRACKER.
Generalized system of relaxed cocoercive variational inequalities governed by nonexpansive mappings
Authors: Gupta Sanjeev
Published: May 2021

The objective of this paper is to study the generalized systems of relaxed cocoercive variational inequalities associated with six nonlinear operators. We proposed three steps explicit iterative methods involving projection operators and give the equivalent fixed point problem of the generalized systems of relaxed cocoercive variational inequalities. This fixed point problem suggests to us the three steps explicit iterative algorithms to obtain an approximate solution of the system under consideration. Strong convergence results are obtained.
A Experimental and Numerical Approach to Evaluate Thermal characteristics a of Heat Pipe
Authors: Rawat M K , Gupta N K
Published: May 2021

Nanofluid as working fluid for the improvement of thermal performance, in case of heat pipe, is the newly emerging area of research. Superior thermal characteristics of nanofluids attracted the researchers towards the application of nanofluid in heat pipes. In present study, a 2D analysis is applied to evaluate the thermal performance of heat pipe having CeO2/H2O nanofluid. The heat transfer analysis of heat pipe having nanofluid (0.5, 1.0, &1.5 wt. % concentration) at operating temperature of 60, 80, 100,& 120°C has been done numerically through CFD simulation and results was compared with the experimental results. The results predicted by numerical analysis show that the application CeO2/H2O nanofluid diminishes the temperature of surface wall and thermal resistance of heat pipe as compared to that of water. The efficiency as well as effective thermal conductivity of the heat pipe increased with the use of CeO2/H2O nanofluid as compared to that of water heat pipe. A good agreement has been observed between experimental and numerical results. The present study concludes that heat pipe using CeO2/H2O nanofluid as working fluid has better heat transfer characteristics than the water.
Automated Detection of Coronary Artery Disease using Machine Learning Algorithm
Authors: Sinha Dibakar , Sharma Ashish
Published: May 2021

Data mining, an excellent development technology for discovering and gathering essential knowledge from vast data collection that can help analyze and draw up trends for decision-making in the industry. Talking about the medical sphere, data mining can be used to uncover and withdraw useful data and trends that can be helpful in clinical diagnostic results. The research focuses on the diagnosis of heart disease, taking past evidence and information into account. To achieve this SHDP, non-linear SVC with RBF kernel algorithms is designed to perfect this SHDP (Smart Heart Disease Prediction). The final is a useful algorithm to look for the right combination of hyper parameters to increase the precision of the algorithm (C, α). The requisite data was arranged in a structured way. The following features are derived from medical profiles for the estimation of the risks of heart failure in a patient: BP, age, sex, cholesterol, blood sugar, etc. The collected characteristics serve as an input to the Navies Bayesian heart disease prediction classification. The data collection used is divided into two parts, 80% of the data are used for preparation, and 20% are used for research. The method suggested includes data collection, user authentication, and log in (based on application), classification through Navies Bayesian, prediction, and safe data transmission via the AES application (Advanced Encryption Standard). An average accuracy, specificity, sensitivity, precision, 93.53% f-score, 89.22%, 91.24% and 86.98%, respectively. This method is also possible in clinical settings to help clinicians predict cardiac arrest.
Effect of PET bottle pieces and waste wrapper fibers on concrete compressive strength
Authors: Mistry Maulik , Rane Gaurav
Published: May 2021

In this study, the main goal was to look into the effect on concrete’s compressive strength by the addition of used PET bottle pieces & wrapper strips collected from waste generated on railway stations. To achieve the target compressive strength for M50 grade concrete, strips were cut from waste wrappers and shredded polyethylene terephthalate (PET) pieces from PET bottles were used. Waste wrapper strips were cut down in three different aspect ratios and four different proportions, along with differing proportions of shredded PET bottle pieces. After 28 days of curing, compressive strength was determined and it is observed that the compressive strength of concrete was decreased by the inclusion of wrapper strips &PET bottle pieces in different ways. Mix ID M4 i.e. 5 × 30 mm, 7.5 gm wrapper &50 gm PET bottle pieces offer better performance relative to the other Mix IDs as compared to the control mix at 28 days. Therefore, 5 X 30 mm size strips of wrappers along with 50gm of PET bottle pieces are the best mix for the compressive strength of concrete compared with other mixes. In the case of proportioning different sizes of shredded wrappers used along with PET bottle pieces, improved results are obtained relative to all other Mix IDs as relative with the 28- day control mix. Multiple size strip of (PET) wrapper with a mixture of (5 × 20 mm, 2.5 gm), (5 × 30 mm, 3 gm), (5 × 40 mm, 2 gm), and 25 gm of broken bits of PET bottles is the better combination for concrete compressive strength than any other combination.
A comparative study of different kinematics - based methods to predict the time of slope failure
Authors: Philip Shimol , Rakendu R. , Philip Joe G.
Published: May 2021

Landslide forecasting is considered one of the key components of early warning systems. Predicting landslide failure at the slope-scale is a major scientific challenge, but on the other hand, it can mitigate the consequences of slope failures in terms of both human lives and economic losses. Therefore, landslide forecasting is a subject worthy of further research efforts due to its social implications. Landslide forecasting consists of the prediction of a slope failure in spatial and/or temporal terms. Temporal prediction can be performed at a regional/global scale or on a slope-scale. This paper focuses on the different methods for temporal prediction of landslides on a slope scale based on kinematic parameters such as displacement and its derivatives (velocity and acceleration). These kinematic parameters are directly related to the stability conditions of the moving mass. This paper accurately explains the correlation between the kinematics and the collapse time of a slope. Also, the present study systematically explains and compares the methods such as the empirical and semi-empirical methods for forecasting the failure time of slopes with their corresponding advantages and limitations. Finally, a detailed outline of the future technology and risks in this area are also introduced in this paper.
Use of C&D Waste in Road Construction: A critical review
Authors: Ray Arpan , Nanda Radhikesh Prasad , Roy Pronab
Published: May 2021

Sustainable development pickup its importance as population of world is increasing day by day. Demand and supply of natural resource in construction of road is facing great challenge for world pavement industry. Parallel to this, there was big challenge to dispose construction and demolition(C&D) waste according to environmental and economic growth of society. This paper focused on review of literature in use of C&D waste in road construction and on suitable alternative materials, better performance of road as well as the gap in the existing knowledge in construction. Some practical problem, suitability of C&D waste as road aggregate is also discussed.
Development of geopolymer concrete mixes with ambient air curing
Authors: Ahmed Adil , Kumar S Sundar , Nanda R P
Published: May 2021

Mix design for geopolymer concrete is yet to evolve. Though geopolymer concrete has made the much required transition from laboratory to the field, due to inherent difficulties such as huge variation in the chemical composition of the raw material, the sensitivity of this composition and the chemicals involved in the fresh and hardened properties have led to most of the mix development through trials with the actual materials. The aim of the work reported in this paper was to design an optimum mix proportion for geopolymer concrete using fly ash and ground granulated blast furnace slag (GGBS) as an aluminosilicate source, which has good workability, slump retention, and compressive strength without special curing requirements. A total of 10 mixes were prepared with varying fly ash to GGBS ratios. Ambient curing for 28 days was adopted for all mixes; however, heat curing at 85°C for 24 hours, followed by ambient curing, was adopted for one mix alone. It was clear that with the increase in GGBS content, there was a reduction in setting time, and the mix set faster. However, with more GGBS, greater strength was achieved at a relatively milder alkali activator solution. When the GGBS content increased beyond a certain level, the slump retention time reduced to levels where the mixes were unfit for practical applications. However, it can be concluded that with a judicious choice of fly ash and GGBS proportions, a strength of as high as 60MPa can be achieved in geopolymer concrete without any special curing methods.
Condition assessment of the structural elements of a reinforced concrete structure using non-destructive techniques
Authors: Gupta Nakul , Gupta Ankur
Published: May 2021

Assessment of the strength and durability properties of structural elements of a reinforced concrete structure can be of great importance for either tracing potential damaged areas or for carrying out the reliability analysis. Composite materials, these days have become an integral part of any construction. Most of the structures are built using concrete as the construction material. Inspite of the strong and durable nature of the concrete as a material, the RCC structures still face common structural issues that includes cracking, spalling, rusting of reinforcement, dampness, acid attack, carbonation etc. If these issues are left unattended during the initial stages then they may cause serious distress in the structures. This paper reports the condition assessment of the structural elements of a residential building using non-destructive techniques. The hardness and the strength of the cover concrete has been assessed using rebound hammer test, structural integrity and homogeneity by ultrasonic pulse velocity test, Additionally, carbonation test and resistivity test were also conducted to assess the extent of corrosion. The results of the assessment have shown a noteworthy decay in the strength and the durability properties of the structural elements.
Role of Spatial Design in Green Buildings-A Critical Review of Green Building Rating Systems
Authors: Katiyar Manoj , Sahu Ashok Kumar , Agarwal Sanjay , Tiwari Pravesh
Published: May 2021

Green Building is a movement today and given the resources, all buildings aspire to be green certified. While making green building, the task is to achieve efficiency of site, energy, water and waste. The effort is rated and ranked through different green building rating systems prevalent across the world and certification label is issued based upon the credits achieved. This research paper carries out a comparison of all rating systems currently available. The credits are studied and classified under various themes (Architecture, MEP, Materials and Practices). There are further two categories under each theme-products/technology and design. Each credit is put under one or the other category and theme. Categorization of credits revealed some astonishing facts and one of the most astonishing facts is that spatial design/architectural design hardly figures in green building rating systems across the world. Most of the credits can be earned through incorporation of more efficient technology/products. There is very little importance given to design input. While credits can be awarded for selecting higher efficiency chiller, there is no means of comparing efficiency of one type of building design to another simply because base case is different for each building in terms of design. The study reveals that potential of architectural design in achieving efficiency has totally been ignored through credits awarding system. The study concludes that some more credits need to be added to the existing system to take into account the impact of architectural design in performance evaluation of green buildings which would make not just the buildings but architecture of these buildings also green.
Assessment of indoor air suspended particulate matter in GLA University campus, Mathura
Authors: Sharma Vivek , Islam Raisul , Raghvendra Singh Kunwar
Published: May 2021

Indoor air quality represents the quality of air inside room. It affects the health and comfort of the residents. Hence it is very essential to measure the quality of air inside buildings and rooms. In this study, air quality of computer lab of GLA University has been assessed. Particulate matter (PM) is a common air pollutant, including of solid and liquid particles suspended in the air. Normally used indicators PM that are related to human well-being refer to the concentration of particles with a thickness of less than 10 μm. Therefore, for assessment of indoor air quality PM10, PM2.5 and PM1 has been monitored for one week. All observed diurnal data-sets have been represented by box plot. This research is very useful for policymakers of GLA University. Based on indoor air quality, classrooms and laboratories can be designed for good health of students
Study of traffic flow and associated noise pollution near GLA University, Mathura (India)
Authors: Dubey Payai , Singh K. R. , Kumar Goyal Sudhir
Published: May 2021

Urbanization is increasing at a very fast rate in our country; road length and its conditions are also improving. Therefore, the number of vehicles also increasing this has led to traffic congestion on roads and noise pollution. The transportation sector is one of the major contributors to noise in an urban area. The main objective for this research was to characterize the traffic noise on the GLA University, Mathura, India. The research work of this paper is divided in two sections: (i) Traffic Study on NH-19 (ii) Traffic noise measurement at peak hours. The study includes the campus area at GLA University. The study is conducted using Sound Level Meter SLM 100 type 2. The results were compared with WHO guidelines, which states that noise level should not exceed 55 dB. Moreover, because of continuous traffic noise on NH-19 is causing increase in health issues. The impact can be harmful GLA University staff, students and people living in campus area. Hence, it can cause disease such as concentration difficulty, irritation, annoyance and are most prominent disorders due to continuous traffic noise.
Comparison of Mechanical properties of flyash-GGBS based GPC and flyash-alccofine based GPC with different concentrations of alkaline activators
Authors: Ramesh Vemundla , Srikanth Koniki
Published: May 2021

Geo-polymer concrete (GPC) is the perfect solution to replace the conventional concrete making use of unwanted materials such as fly ash, GGBS, Alccofine etc.,. It is noted that many researchers have worked on geopolymer concrete and a tremendous work is going on too, but unlike conventional concrete there is no proper methodology available to follow. GPC has preferable mechanical properties when differentiate to conventional concrete. Replacing GGBS and alccofine with fly ash upto some extend can eliminate oven curing and it becomes suitable to use ambient curing conditions effectively. and This study deals with different proportion of various source materials and concludes at which proportion and concentration the compressive strength and workability is higher. For Alccofine combination with fly ash gives better results than GGBS combination with fly ash but if economy is the criteria alccofine is not preferable as it is costlier than that of GGBS.
Hardware Implementation of Prepaid Power Consumption Using Coin Box System
Authors: Kumar Vikash , Kumar Raghuwanshi Sanjeev
Published: May 2021

For enhancement of technology our implemented system is helpful for the human beings for in this world. Basically in guest house, lodges, hotels and rest houses the power consumption is not measurable by the customer and the owner. So that it is important to control the consumption of power proportional to the payment otherwise the owner pays the higher bills and faces the loss in running the hotel. For we develop the pre-paid system for power consumption by using some simple discreet components and microcontroller programmed for desired output. Using highly advanced ICs and with the help of growing technology the proposed hardware has been successfully implemented but by using pre-paid card in place of token/coin we can make a more advanced system. Moreover, this system, for enhancing the requirement the technology the system can be replaced with GSM (Global System for Mobile Communication) Modems, it will help the tracking of the consumers load on a regular basis is possible, it help in the maximum demand for tracking, more over instead of recharging the chip has be detected through online theft, the readily used in cell phones available recharge cards (smart cards can be introduced. Using with given mechanisms, consumers much user friendly for recharging their meters and at their convenience.
A study on firms’ communication based on artificial intelligence and its influence on customers’ complaint behavior in Social media environment
Authors: Agnihotri D , Kulshreshtha K , Tripathi V
Published: May 2021

The purpose of the study is to understand actual behavior of customers and firms by analyzing the real time interaction between firm and customers on social media platform. The study also pursues to assess the way firms respond to the customer’s complaint on different social media platforms through autobots based on artificial intelligence. The study identifies official Facebook and Twitter pages of top online shopping portals. The number of complaints and responses posted on these pages are documented and analyzed. Netnography method is used for data collection. Connotation key words are used for selection of comments and tweets. The study concludes that organizations respond to the most of the complaints publically but they further ask for the personal interaction with the complainer to resolve the complaint through pre-defined statements. The study has also revealed that pre-defined statements stated by autobots based on artificial intelligence seem insufficient to resolve customer complaints. The limitation of the study is associated with the netnography technique, which has restricted the exploration to only those consumers who have posted comments on Twitter or Facebook. Hence, other physical factors i.e. customer responses through numerous offline modes were absconded. The study is limited to Facebook and Twitter only. This study is limited to four major online shopping portals; it leaves a lot of scope to analyze other industries such as banking and insurance, hospitality, aviation etc. The output of the study suggests that the firms need to be conscious enough to provide customized and adaptive solutions to the customers’ complaints instead of pre-defined responses through artificial intelligence as it lacks emotions to empathize with customers’ issues. As per the literature of review, methods chosen in previous researches by researchers were having a methodological gap, as netnography in social media environment remained unused earlier, which has reinforced to analyze original behavior of customers and responsiveness of organization.
A Survey on Image Captioning datasets and Evaluation Metrics
Authors: Sharma Himanshu
Published: May 2021

In the task of image captioning, a natural language explanation is generated for a given image. It uses the subfields of artificial intelligence: computer vision and language generation. Convolutional Neural Network (CNN) is generally applied to capture image features and language processing models such as Recurrent Neural Network for sentence generation. In this paper, various datasets and evaluation metrics which are useful for image captioning task are discussed. Also, the datasets and evaluation metrics applied by the state-of-the-art image captioning models is summarized.
Signal Processing and Machine Learning Approaches and Evaluation for Indian Classical Music
Authors: Shastry Rajashekar , Bai Anita
Published: May 2021

In the field of signal processing, a considerable amount of work has been done in the analysis and implementation of various techniques related to speech signal processing. When it comes to the Music signal processing, the techniques that are originally developed for speech signal processing have been applied to music signal with good results. In comparison with Indian classical music, lot of research work done in Western classical music on music audio analysis like information retrieval, singer/instrument identification, genre detection, etc.,. This paper provides an overview of some signal processing, and machine learning techniques that specifically applied to the Indian classical music for analyzing and identifying features such as tonic identification, genre classification, raga recognition, music transcription, rhythm, and timbre. We will look at how particular features of Indian Classical music signals impact and how these features are extracted.
Comparison of two Deep Learning Methods for Classification of Dataset of Breast Ultrasound Images
Authors: Saxena Aditya
Published: May 2021

Breast cancer is the prominent cancer types which account to high mortality. Early detection could serve to improve clinical outcomes. Ultrasonography is a digital imaging technique which is used for differentiating benign and malignant tumors. Recently a dataset of breast ultrasound image has been released which gives opportunity to apply machine learning methods over it and enable one to automatically classify them in the respective tumor class. In the present study, I compared the performance of two deep learning methods: AlexNet, and MobileNet for the classification of breast ultrasound images using an augmented data set of 12000 images (6000 each of benign, and malignant) and received an F1-score of 0.914 and 0.974 respectively so herewith concluded that the later deep learning approach performs better then the former in classifying the ultrasound images of breast tissues in benign and malignant cancer types.
Solving N-Queen Problem by Genetic Algorithm using Novel Mutation Operator
Authors: Sharma Sachin , Jain Vinod
Published: May 2021

N-Queen is a well-known NP-Hard problem. In N-Queen problem, the challenge is to place n queens on n*n chess board such that no two queens can attack each other. The problem can-not be solved using traditional algorithms. Genetic algorithm is a well-known optimization technique. The problem has to be represented in genetic form to solve it using genetic algorithm. In this paper a new mutation operator is proposed to solve N-Queen problem. The proposed algorithm is applied on some instances of N-Queen problem and it is observed that the proposed performs better as compared to other existing algorithms.
Morphology-based identification and classification of Pediastrum through AlexNet Convolution Neural Network
Authors: Gaur Ashish , Yadav D.P. , Pant Gaurav
Published: May 2021

In general solutions and outcomes to an issue in image processing, a ton of trail and examination with an enormous assortment of test photographs is incorporated. Pediastrum, which comprises of pigments like carotene, xanthophyll, chlorophylls, and other nourishing elements like complex sugars, major and minor minerals, and protein, enzymes, fiber, is a minute coccal shaped colony forming green algae. In this research, an attempt was made to solve the problem of identifying and classifying different species of Pediastrum with the aid of CNN based deep learning model. The informational collection comprising of 12,000 algal pictures was being utilized by, AlexNet CNN (Convolution Neural Network) model for the training and validating purposes. The features like the presence of sporopollenin in the cell wall, the structures and the functions of the cells, and the structural properties of coenobia make the basis for automated classification by AlexNet deep learning model. The efficacy of the proposed approach is demonstrated by an experimental outcome of 99.54 percent classification accuracy with precision and Fl-score more than 0.98.
Innovative service recovery of customers by food aggregators using sentiment analysis
Authors: Chauhan Sanjeev , Upadhyay Yogesh , Singh S K
Published: May 2021

In the global era, technology plays a vital role in determining the strong market position for the modern-day organizations. Food aggregators make efforts to identify the reasons for service failure in case of customers not in direct communication with them. The ascending online food ordering market has augmented the involvement of peers’ day-to-day interaction on social media resources. Food ordering brands like Swiggy, Food panda, Zomato who have garnered quite a reputation by tapping their audience online via enticing them with the idea of getting quality restaurant meals right at their doorstep with just a click are slowly being victimised by their web of problems. Online marketing had made daily food ordering easy for the users but, the excessive demand of orders at a time can lead to delay in deliveries, loss in quality etc. henceforth, targeting brand’s esteem and loss of valuable consumers. These food ordering websites collaborate with a wide network of restaurants/hotels in a city and provide quick delivery of food products to their customers using aggregator business model. They act as middlemen who deliver the food from restaurants to user’s home maintaining a brands name. The current study focuses on tracking the sentiments of the customers through which these brands can identify the issues which leads to unsatisfactory responses or reviews on various online and social sites. Further study pave ways for innovative service recovery mechanism to frame a sustainable business practice for gaining competitive advantage. In this study, sentiment analysis tools like IBM Watson, social mention and tone analysers were used to observe the reactions of customers and used disruptive technology to analyse how brands could improve their service recovery behaviour to secure and reach more customers by figuring out the reasons of service failure.
Study of diffusion bonded flat plate closed loop pulsating heat pipes with alternating porous media
Authors: Betancur Luis , Facin Arthur , Gonçalves Priscila , Paiva Kleber , Mantelli Marcia , Nuernberg Gustavo
Published: May 2021

This work aims to discuss the application of diffusion bonding process in the fabrication of flat plate pulsating heat pipes and to analyze the thermal performance effect of porous media structures applied to alternating channels in the evaporator section and compare it with a smooth conventional flat plate pulsating heat pipe. For that, two different copper flat plate pulsating heat pipes with five turns and 1.5 mm of inner diameter channels were fabricated, using diffusion bonding. Samples were made with two different diffusion process to evaluate the ability of the resulting device to keep the vacuum, avoiding the use of filler material during the welding process, which could result in contamination and, therefore, undesirable corrosion on both internal and external heat pipe surfaces. The results allowed to assess the quality of the bonded interface of two different configurations of the diffusion process. Microscopic results obtained on controllable pressure furnace and non-pressure control were analyzed, where the diffusion process with controlled pressure presented best results of continuity, alignment, and tightness. A comparison of the heat transfer characteristics between the two devices was performed under the same experimental conditions; for both devices, the thermal resistance in horizontal position showed to be like heat transfer of pure conductive copper plate. However, pulsating heat pipe containing smooth channels showed the lower thermal resistance in vertical position and filling ratio of 50%.
Water-filled heat pipes for CubeSat thermal control
Authors: van Gerner H J , Brouwer H , de Groot Z , Guo J
Published: May 2021

Currently, the amount of electrical power that is available for CubeSat’s is very small and for this reason, simple thermal conductance through the frame of the CubeSat is sufficient for most CubeSat missions. However, deployable solar panels have been developed recently and peak powers up to 40W can now be generated. This higher generated electrical power results in more waste heat and potentially too high temperatures inside the CubeSat. For this reason, the use of water-filled heat pipes is studied, since these are cheap, widely commercially available, and can be bent in the desired shape. Both the condenser and evaporator thermal resistance and the total heat transfer capacity of these heat pipes have been measured for a wide range of temperatures with a unique automated setup that uses Peltier elements to control the temperature. Furthermore, the heat pipes have been subjected to multiple freeze/thaw cycles and start-ups from a frozen state. After these successful tests, a heat pipe was integrated in a CubeSat and tests were carried out in several orientations. The tests show that commercially available water-filled heat pipes are suitable for CubeSat thermal control.
A method of fast quality control inspection of loop heat pipe
Authors: Huang Bin-Juine , Huang H H , Liang T L , Yang P E , Hu S S
Published: May 2021

The dynamic behaviour of loop heat pipe (LHP) changes with heat load and physical properties of LHP such as fluid charging, wick material, and tolerance in manufacture. The start-up phenomena of a LHP can be classified into four modes, according to the heat load Qin
: failure mode, oscillating mode, overshoot mode, and normal mode. It is found that the operation mode is related to the rate of temperature rise in evaporator during initial transient performance using a step heating load. The abnormal high rate of temperature rise can be observed for LHP with failure, oscillating or overshoot mode performance. Based on this phenomenon, the normal-mode performance of LHP can be assured from a short transient test in about 80s using a step heat load, instead of using steady-state test (taking 1,800s). This transient test method has been applied in the quality inspection of commercial loop heat pipe in mass production. No LHP failure was found for more than 10 years for about 30,000 sets of street LED luminaires designed with LHP.
Black box modelling of a latent heat thermal energy storage system coupled with heat pipes
Authors: Arteconi A , Ferracuti F , Tascioni R , Mahkamov K , Kenisarin M , Costa C , Cabeza L F , de Gracia A , Halimic E , Mullen D , Lynn K , Cioccolanti L
Published: May 2021

This paper presents black box models to represent a LHTESS (Latent Heat Thermal Energy Storage System) coupled with heat pipes, aimed at increasing the storage performance and at decreasing the time of charging/discharging. The presented storage system is part of a micro solar CHP plant and the developed model is intended to be used in the simulation tool of the overall system, thus it has to be accurate but also fast computing. Black box data driven models are considered, trained by means of numerical data obtained from a white box detailed model of the LHTESS and heat pipes system. A year round simulation of the system during its normal operation within the micro solar CHP plant is used as dataset. Then the black box models are trained and finally validated on these data. Results show the need for a black box model that can take into account the different seasonal performance of the LHTESS. In this analysis the best fit was achieved by means of Random Forest models with an accuracy higher than 90%.
Thin film evaporation model for two-phase capillary heat transfer devices: examination of boundary conditions and vapour pressure gradient
Authors: Ahmed S , Pandey M
Published: May 2021

Thin film evaporation model has been used by several researchers to study the transport phenomena of two-phase capillary devices, such as heat pipes and capillary pumped loops. The present work is focused on mathematical modeling of the evaporation phenomena in such devices. Liquid-vapour interface in the evaporator is modelled using a thin film model and the lubrication approximation, along with a slip boundary condition at the wall and a shear boundary condition at the interface. Different models are used for the evaporating mass flux and the vapour pressure gradient at the liquid-vapour interface is considered. An attempt is also made to determine the non-evaporating film thickness that satisfies the underlying physics. The film thickness profile and the pressure components are obtained by numerical simulations. It is found that the choice of the evaporating mass flux model has a significant effect on the results, and is very important for heat transfer characterization.
Beam Tracking Using Least Mean Squares Algorithm for single-cell Massive MIMO Communication System
Authors: Asi Ban A. , Mohmood Farhad E. , AL-Ibadi Mohanad A.
Published: May 2021

Millimetres wave (mm-wave) is an attractive option for high data rate applications in the 5G wireless communication systems that require proper beamforming and channel tracking. In this paper, we study, analyse and compare the performance of two closely related stochastic gradient descent-based approaches, namely the least mean square (LMS) algorithm, and the normalized least mean square (NLMS) algorithm, for tracking the transmit array beam in addition to the channel status. These adaptive filters usually result in a trade-off between convergence and accuracy. We found that the quality of the tracking results, measured in mean squared error (MSE) sense, are heavily dependent on the present step-the size of the gradient descent.
On the Performance of Cooperative Relaying with Maximum-Ratio Combination (MRC) for mmWave Systems
Authors: Ali Reyam H. , Mahmood Mahmood A. , Ahmed Mohamad A.
Published: May 2021

In this paper, cooperative communication using a two-way relaying network (TWRN) is considered for millimeter-wave (mmWave) communications. Two schemes of TWRN are employed for cooperation and performance evaluation, which are amplify-and-forward (AF) and decode-and-forward (DF) relays. Furthermore, maximum-ratio combination (MRC) is utilized in each node in the proposed systems. It is noteworthy that MRC is exploited in this paper as a channel equalization and also to maximize the strength of the received signals at each node. The performance is evaluated for the proposed systems over 28 and 73 GHz using one and two parallel AF and DF relays in the presence of the direct path. Moreover, compassion between the two frequencies is achieved, via obtaining the bit-error-rate (BER) against different values of signal-to-noise ratios (SNR)’s, by assuming the same distances between the source, relay/relays, and the destination. The results show the outperforming of 28 GHz in this performance metric, i.e. BER-SNR, by using AF relaying, due to the amplification factor added to the signal to compensate for the inherent attenuation in this frequency band. Moreover, the proposed DF relay schemes have limited compensation to the attenuated signals comparing to the AF relay.
A Rectangular Monopole Filtenna with U-shaped Slot for 5G Applications
Authors: Al-Arajee T H , Sayidmarie K H
Published: May 2021

A filtering antenna for 5G applications is proposed in this study, where the resonant element has a U-shaped slot embedded into the microstrip feed line so that no extra size is required. The proposedfiltenna has a very compact size of only 35 * 47 mm 2. Using CST Microwave Studio Suite, a comprehensive parametric analysis was done to evaluate and optimize the characteristics of the proposed filtenna. The filtenna is aimed for the 5G 3.4-3.8 GHz, as it covers a bandwidth of 412MHz (3.395-3.807GHz) witha good reflection coefficient of -22.96dBat the center frequency. The U-shaped slot enhances the lower shoulder of the antenna frequency response and has no effect on the radiation at the desired band.
Obtaining Performance Similar to Rectangular Planar Antenna Using Crossed Arrays with Smaller Number of Elements
Authors: Khmees Abdulrazaq Abdulhaq , Mohammed Jafar Ramadhan
Published: May 2021

Conventional rectangular planar arrays with fully filled elements are practically very complicated especially for large arrays. They usually occupy a large space. Thus, any reduction in the space and the number of the array elements is highly desirable in many applications. In this paper, the authors present a novel technique for obtaining a performance similar to that of the conventional rectangular planar antenna using two orthogonal crossed arrays with a smaller number of elements. The proposed technique consists of redesigning the amplitude element excitations of only two crossed arrays using either deterministic or optimization algorithms. Simulation results are shown to prove the proposed idea.
Comparative Study the Effect of Antenna Selection on Capacity and Energy Efficiency of 5G Systems
Authors: Abdullah Sawsan N. , Mahmood Farhad E. , Mohammed Ali Y.E.
Published: May 2021

As a result of the rapid growth in wireless communications and the increase in the number of users of cellular phones around the world, massive multi-output, and multi-input (massive MIMO) systems have been used. The main drawback of such a system is the increase in the number of antennas and the amount of energy consumed. To mitigate that the number of active antennas can be reduced to save some energy. In this paper, we will study different algorithms for choosing the suitable antennas in MIMO systems, subject to keeping an acceptable level of bit rate and energy efficiency in the system. The study will also consider the amount of complexity for each algorithm based on the consumed time to perform each algorithm in MATLAB.
Performance Optimization on GPGPU & Multicore CPU Using Roofline Model
Authors: Allayla Noor M. , Dawwd Shefa A.
Published: May 2021

The roofline model introduced in this paper to evaluate the best optimized platform for training the neural network that used to recognize handwritten digits under multicore CPU and general-purpose GPU (GPGPU) as hardware environment. The pattern parallel training technique for MNIST dataset is applied. The parallel network training of MNIST using different data layout of multicore CPU and GPGPU is presented. Different bottlenecks have been explained by applying the roofline model. The most suitable platform is selected according to layouts and constrains either for memory or computation bounds. The computational intensity of all rooflines is moved toward right, then the performance is increased. As a result of optimization, and with the diversity of the available data size, core number, operational strength, the most suitable hardware platform is selected.
Model of Integrated of Car Brake-Active Suspension of Quarter Car Model By Using LQR Control Under Periodic Road Excitation
Authors: Harly Muchammad , Marji  , Yoto  , Paryono
Published: May 2021

The most important technology in a vehicle is the stability of the direction of the vehicle and the comfort of the passengers. For stability, direct yaw control is used via ABS / TCS / DSC, while for convenience, use the active suspension. These two solutions also contribute to one another. In this research paper is produced and explained about the use of LQR control to control the response of the sprung mass to achieve high damping ratios in isolating the excitation force from nonlinear road surfaces. The simulation results prove that the damping ratio controlled by LQR was better than compared by using PID.
Analysis and Simulation of a Single Phase Nine Level Inverter with Reduction in Power Switching Devices
Authors: Mahmood Saif S. , Younus Shawkat M.
Published: May 2021

This paper present analysis and modelling of single phase nine level inverter, a Wide range of Modulation index (M) varied between 0.05-1.05 is achieved by two switching strategies (Optimized harmonic stepped waveform (OHSW), (Optimal minimization of total harmonic distortion (OTHD)) the first strategy focusses on harmonic elimination and the other on reducing output voltage total harmonic distortion (THD). Calculation of switching angles for both equal and unequal dc sources is done by Genetic Algorithm (GA). simulation in Matlab, PSpice and PSIM is presented in this work.
The influence of the interface layer between the electron transport layer and absorber on the performance of perovskite solar cells
Authors: Qasim Agha Dena N , Algwari Qais Th
Published: May 2021

High efficiency, lightweight, and cost-effectiveness put the perovskite solar cells to the top of the focus researches of solar cells. The architecture of the cell especially the energy band alignment at the interface is a critical issue in the cell performance. In the current paper, the solar cell structure under investigation consists of TiO2, CH3NH3PbI3, and Spiro OMe TAD as electron transport layer, absorber and hole transport layer respectively. A 3C-SiC material with energy gap of 2.420 eV was used as interface layer. The role of the interface layer between the perovskite and electron transport layer was considered. Before inserting the interface layer, a parametric study including the thickness and doping of each layer, was achieved. The results showed that the best performance of the cell at a thickness of 400 nm, 300 nm, 200 nm for absorber layer, ETL, and HTL respectively, with a doping concentration of 1014 cm-3, 1019 cm-3, 1019 cm-3 for the same layers. These parameters give a Voc, Jsc, FF, and PCE of 1.11 V, 28.9 mA·cm-2, 83.19%, and 26.88% respectively. Inserting an interface layer improved the performance of the cell where the PCE increased over 29% at a thickness of 90 nm. The results showed that the parameters of the interface layer play a significant role in cell performance.
Design and simulation of cascaded H-bridge 5-level inverter for grid connection system based on multi-carrier PWM technique
Authors: Maaroof Hadeel S , Al-Badrani Harith , Younis Ahmad T
Published: May 2021

Cascaded H-Bridge (CHB) multi-level inverter has become attractive in medium voltage and grid connection to improve power quality with high efficiency, and low switching losses. Voltage Oriented Control (VOC) regulates the injected power and the connection between the cascaded H-bridge inverter and the utility grid. In the modulation stage for the VOC, there are several techniques such as Space Vector Pulse Width Modulation (SVPWM), Multi-Carrier Pulse Width Modulation (MCPWM), Selective Harmonic Elimination (SHE) used to obtain gating pulses for the IGBTs switches. In this paper, a three-phase 5-level CHB inverter with a grid connection system is present and the technique of MCPWM is used. A comparative study between each method of (MCPWM) using MATLAB/Simulink environment has been done on the Total Harmonic Distortion (THD) for inverter phase voltage and current with different injected reference current values. It is found that phase current THD is less with the Phase Shift PWM (PS-PWM) technique.
Evaluation of Ground Motion Definition on the Seismic Analysis of Reinforced Concrete Moment Frame Structure
Authors: Ornthammarath T , Myint K M
Published: May 2021

The primary objective of the study is to analyze the effect of the horizontal definition in the ground motion selection, in which, how the target spectra of DBE and MCE resulted from the geometric mean method and NGA West-2 Sa RotD100, the maximum direction method is different from each other. The analysis of the seismic performance of the building is the secondary aim of the research. The linear design methods of equivalent lateral force analysis, response spectrum and seismic response history analysis are performed based on the Myanmar seismic design code to figure out and compare the building responses such as story displacement, story drift, story base shear, and story overturning moment. In this study, the irregular shaped RC building structural responses are also explored with equivalent lateral force analysis (EQLF), response spectrum analysis (RSA) and linear response history analysis (LRHA). The recent ground motion definition response shows great potential in improving the performance-based design of considered structures.
Reliability-based prediction of landslide using efficient Monte Carlo Simulation
Authors: Joe E J , Ali N , Jusoh S N
Published: May 2021

Several studies have attempted to develop thresholds for prediction of landslide initiation due to antecedent rainfall by using the physical-based approach. The approach offers a better understanding of the underlying process of the landslide mechanism. In the previous studies, however, determinate values of hydro-mechanical soil parameters are commonly considered, neglecting the uncertainties of the variables. Thus, this study aims to propose a relatively computationally, inexpensive reliability approach to address the uncertainties of the multivariate. The application of the proposed model is demonstrated by taking a case study from Sabah, Malaysia. The Latin Hypercube Sampling was adopted for efficient sampling, while the dependencies of the multivariate were modelled using a higher-order copula. The infiltration process and slope stability were assessed based on a fully-coupled seepage-deformation and shear strength reduction technique, respectively in a finite element programme. The probabilities of failure for various antecedent rainfall condition were computed by using Monte Carlo Simulation. In order to reduce the computational cost of the simulation, the Multilayer Perceptron regressor was applied to form the non-linear surrogate model for an implicit limit state function.