Frequency: Quarterly E- ISSN: Awaited P- ISSN: 2249-1406 Abstracted/ Indexed in: Ulrich's International Periodical Directory, Google Scholar, SCIRUS, Genamics JournalSeek, getCITED, JOURNAL directory, EBSCO Information Services
Quarterly published in print and online "Inventi Impact: Tech Research & Reviews" publishes high quality unpublished as well as high impact pre-published research and reviews catering to the needs of researchers and professionals. This journal deals with the technological aspects of engineering fields. Papers are invited from all the disciplines, particularly from civil and architecture; mechanical and automobiles; electrical and electronics; computer science and information technology; chemical engineering and metallurgy; textile and polymer engineering; industrial production; medical electronics; telecommunications; earth and atmospheric sciences; biomedical engineering and engineering biotechnology; engineering physics, mathematics and statistics.
A 4 × 4 wideband millimeter-wave (mmWave) slot array antenna excited by the TE440 mode based on the groove gap waveguide is presented in this paper. A vertical waveguide located in the center of the cavity and two ridges are used to excite the TE440 mode. In addition, a pair of corrugations acting as the soft surface are added on the top of the array antenna to improve the gain. A 4 × 4 prototype is fabricated and measured. The measured and simulated results are in great agreement. The measured results show that the proposed array antenna achieved an impedance bandwidth (|S11| < −10 dB) of 26.7% from 26.14 to 34.2 GHz, and the maximum gain is 17.7 dBi. The proposed array antenna avoids the complicated feeding network, allowing us to reduce the manufacturing cost....
Non steady state thermal conductivity of ABS was estimated using an analytical approach in a Cold\nClimate Chamber at 10 and 14. Two hollow cylinders of ABS of varying thickness were used\nto estimate the conductivity. The material was porous but the porosity was unknown. This paper\nis a case study to understand, if it is reasonable to estimate the thermal conductivity using the\nanalytical varying thickness approach....
This research aims to build a computer-based system for measuring slub yarn characteristics and evaluating the results using\r\nstatistical methods. The measuring system was based on the electrical condenser of the Uster evenness tester as ameasuring sensor.\r\nA digital storage oscilloscope was used to convert the analogue output signals into digital data to be recorded on a computer. A\r\ndesigned computer program was constructed usingMatLab language for signal analysis based on a proposed method. Final results\r\nfrom this system contained graphical plots for the three measured slub yarn geometrical parameters slub length, slub distance, and\r\nslub thickness and a final report for all the measured slub yarn characteristics. The results of tested slub yarn samples showed that\r\nactual slub geometrical parameters differ from nominal values and the difference had two level: prevailing difference and outlier\r\nvalues. Outliers which are considered slub yarn defects were detected and counted in a final report using the box plot statistical\r\nmethod which could be an effective industrial tool for evaluation of both yarn quality and machine performance.The prevailing\r\ndifference was assessed using histogram comparison which could help in adjusting the setting of slub yarn device to obtain the\r\nrequired appearance....
In this article, a small-aperture, low-profile, and omnidirectional conformal antenna is proposed which can be utilized on space-limited equipment platforms such as airplanes, ships, and vehicles. The antenna consists of an open metal cavity, a discone antenna, a parasitic structure, and a radome. The small aperture and low-profile design of the metal cavity result in a rapid narrowing of the bandwidth of the discone antenna. Therefore, we introduce a parasitic structure that not only enlarges the impedance bandwidth by adding a resonant point, but can also be used to adjust the unroundness of the horizontal pattern. Meanwhile, the conformal design of the antenna with four surfaces of different curvatures is presented. The simulation and testing results demonstrate that the antenna can achieve a VSWR of less than 2 within a bandwidth of 1.95–2.62 GHz (29.3%), with a minimum aperture of 0.43 omnidirectional radiation pattern, with a gain exceeding −2.2 dBi in the azimuthal plane. This antenna offers the advantages of a small aperture, low profile, and conformal capability. Furthermore, the resonances of high and low frequencies can be adjusted through two different structures, enhancing the flexibility of antenna design....
A fractal absorber based on a metamaterial configuration is proposed for dual-frequency\noperation within the UHF band. The miniaturization skills of the proposed fractal shape are used\nto design a dual-band metamaterial absorber cell with reduced size....................................
We investigate a nonlinear realization of the Lorentz transformation defined in 4-dimensional spacetime, and the corresponding\r\ninvariant interval. This new interval is not a quadratic form in the standardMinkowski spacetime, then we search for a description\r\nwhere it becomes a quadratic form in an infinite dimensional vector space. In this extended space, we show how to generate two\r\nclasses of nonlinear transformations, which form a group and interpret the non-linear transformation as compatible relations\r\nbetween atlas of a Lyra manifold....
This investigation presents a heuristic method for consumable resource allocation problem in multi-class dynamic\r\nProject Evaluation and Review Technique (PERT) networks, where new projects from different classes (types) arrive\r\nto system according to independent Poisson processes with different arrival rates. Each activity of any project is\r\noperated at a devoted service station located in a node of the network with exponential distribution according to\r\nits class. Indeed, each project arrives to the first service station and continues its routing according to precedence\r\nnetwork of its class. Such system can be represented as a queuing network, while the discipline of queues is first\r\ncome, first served. On the basis of presented method, a multi-class system is decomposed into several single-class\r\ndynamic PERT networks, whereas each class is considered separately as a minisystem. In modeling of single-class\r\ndynamic PERT network, we use Markov process and a multi-objective model investigated by Azaron and\r\nTavakkoli-Moghaddam in 2007. Then, after obtaining the resources allocated to service stations in every minisystem,\r\nthe final resources allocated to activities are calculated by the proposed method....
Developing a reliable weather forecasting model is a complicated task, as it\nrequires heavy IT resources as well as heavy investments beyond the financial\ncapabilities of most countries. In Lebanon, the prediction model used by the\ncivil aviation weather service at Rafic Hariri International Airport in Beirut\n(BRHIA) is the ARPEGE model, (0.5) developed by the weather service in\nFrance. Unfortunately, forecasts provided by ARPEGE have been erroneous\nand biased by several factors such as the chaotic character of the physical\nmodeling equations of some atmospheric phenomena (advection, convection,\netc.) and the nature of the Lebanese topography. In this paper, we proposed\nthe time series method ARIMA (Auto Regressive Integrated Moving Average)\nto forecast the minimum daily temperature and compared its result with\nARPEGE. As a result, ARIMA method shows better mean accuracy (91%)\nover the numerical model ARPEGE (68%), for the prediction of five days in\nJanuary 2017. Moreover, back to five months ago, in order to validate the accuracy\nof the proposed model, a simulation has been applied on the first five\ndays of August 2016. Results have shown that the time series ARIMA method\nhas offered better mean accuracy (98%) over the numerical model ARPEGE\n(89%) for the prediction of five days of August 2016. This paper discusses a\nmultiprocessing approach applied to ARIMA in order to enhance the efficiency\nof ARIMA in terms of complexity and resources....
Artificial intelligence (AI) has been used in various areas to support system\noptimization and find solutions where the complexity makes it challenging to\nuse algorithmic and heuristics. Case-based Reasoning (CBR) is an AI technique\nintensively exploited in domains like management, medicine, design,\nconstruction, retail and smart grid. CBR is a technique for problem-solving\nand captures new knowledge by using past experiences. One of the main CBR\ndeployment challenges is the target system modeling process. This paper\npresents a straightforward methodological approach to model CBR-based applications\nusing the concepts of abstract and concrete models. Splitting the\nmodeling process with two models facilitates the allocation of expertise between\nthe application domain and the CBR technology. The methodological\napproach intends to facilitate the CBR modeling process and to foster CBR\nuse in various areas outside computer science....
Symbiotic stars are interacting binary systems composed of an evolved star (generally a late-type red giant) and a degenerate or dwarf companion in orbit close enough for mass transfer to occur. Understanding the status of the late-type star is important for developing binary models for the symbiotic systems as it affects the transfer of matter needed to activate the hot component. Infrared observations have been very useful in probing the nature of late-type stars in symbiotic systems. This work presents a set of symbiotic stars observed with SOAR/OSIRIS (R∼3000) in the H-band. We aimed to search for possible molecular circumstellar emission, to characterize the cool companion in these systems, and to confront the new findings with those obtained from the previous K-band classifications. We detected molecular emission from just one object, BI Cru, which displays the second-overtone CO-bands. To fit the observed photospheric CO absorption bands, we used the MARCS atmosphere models. We present our results as a mini atlas of symbiotic stars in the near-infrared region to facilitate the comparison among different observed symbiotic systems....
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