Journal La Multiapp

Journal Information
ISSN / EISSN : 2716-3865 / 2721-1290
Current Publisher: Newinera Publisher (10.37899)
Total articles ≅ 33
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Latest articles in this journal

Lucian Paunescu, Sorin Mircea Axinte, Felicia Cosmulescu, Marius Florin Dragoescu, Bogdan Valentin Paunescu
Published: 9 March 2021
Journal La Multiapp, Volume 2, pp 1-12; doi:10.37899/journallamultiapp.v2i1.286

Abstract:
According to the research objective that was the basis of the paper, an ultra-light glass foam with an apparent density of 0.14 g/cm3 was experimentally made from 98.9% post-consumer glass bottle and 1% CaCO3 as a foaming agent by sintering/foaming at 823 ºC in microwave field with a very low specific energy consumption (0.70 kWh/kg). A very advanced mechanical processing of glass waste (below 32 μm) and a very fine granulation (below 6.3 μm) of CaCO3 were the solutions adopted to obtain this high-performance product. The originality of the work is the use of the unconventional technique of predominantly direct microwave heating with a very high energy efficiency, applied by authors in recent years and presented in several previous papers.
Vandon Borela, Jezreel Matthew M. Ancheta, Jerus Cyril P. Bejar, Loureese Mei L. Garcia
Published: 9 March 2021
Journal La Multiapp, Volume 2, pp 13-19; doi:10.37899/journallamultiapp.v2i1.208

Abstract:
This study aimed to determine the ability of polystyrene in ballpen barrels of making a brick to be more compacted than the ordinary clay bricks. Polystyrene is a synthetic aromatic hydrocarbon polymer made from the monomer styrene that also makes a brick denser. The Wood ash from burned wood are usually used by the gardeners as a good source of potash. Wood ash has an ability of making the bricks lighter than the usual clay bricks. Additional wood ash is better than coal ash, because coal ash has a dangerous chemicals that may harm human. The goal of this study is to lessen the ballpen barrels and wood ash that are not disposed properly and make this in a creative way. Five test was conducted to determine the potential of polystyrene and wood ash namely water absorption test, drop test, efflorescence test, compressive test and heat resistance test. Based from the data gathered, it concluded that polystyrene from ballpen barrel and wood ash with the ratio of 50% Cement, 25% Wood Ash, 25% Ballpen Barrels is effective additives in production of lightweight
Lucian Paunescu
Published: 9 March 2021
Journal La Multiapp, Volume 2, pp 20-28; doi:10.37899/journallamultiapp.v2i1.302

Abstract:
The paper aimed at the experimental manufacture of a foam glass gravel type by sintering at over 900 ºC a powder mixture composed of recycled glass waste (92%), sodium borate (6%), kaolin (0.3%), silicon carbide (1.7%) and water addition (12%). The originality of the work was the application of the unconventional technique of microwave heating through a predominantly direct heating procedure. The product foamed at 908 ºC had a very fine porous structure (pore size between 0.05-0.20 mm) and a compressive strength above the usual level of foam glass gravels (7.8 MPa). The apparent density of 0.28 g/cm3 corresponding to a bulk density of 0.20 g/cm3 and the thermal conductivity of 0.075 W/m·K ensures the thermal insulating character of the material required for use in the specific field of applications of foam glass gravel. The manufacturing process had an excellent energy efficiency, the specific energy consumption decreasing up to 0.70 kWh/kg.
Lucian Paunescu, Marius Florin Dragoescu, Sorin Mircea Axinte, Felicia Cosmulescu
Published: 14 January 2021
Journal La Multiapp, Volume 1, pp 12-22; doi:10.37899/journallamultiapp.v1i6.272

Abstract:
The study aims to test an advanced technique but insufficiently valued in the world in the process of experimental manufacture of borosilicate glass foam. It is about the unconventional technique of heating solids by using the microwave radiation converted into heat. The experimental equipment on which the tests were performed was a 0.8-kW microwave oven commonly used in the household with constructive adaptations to be operational at high temperature. The adopted manufacturing recipe was composed of borosilicate glass waste with the addition of calcium carbonate, boric acid and water in different weight proportions. The material was sintered at 829-834 ºC by predominantly direct microwave heating and the optimal foamed product had characteristics similar to those manufactured by conventional techniques (apparent density of 0.33 g/cm3, thermal conductivity of 0.070 W/m•K, compressive strength of 3.1 MPa and a homogeneous microstructure with pore size between 0.7-1.0 mm). The energy efficiency of the unconventional manufacturing process was remarkable, the specific energy consumption being only 0.92 kWh/kg.
Nyein Mynt, Zaw Aung, Kyaw Lin
Published: 14 January 2021
Journal La Multiapp, Volume 1, pp 6-11; doi:10.37899/journallamultiapp.v1i6.278

Abstract:
This practicum is to define the study properties of the sampling theorem. Understand the effect of selecting the sample size and its effect on the signal recovery process. The experiment utilizes a computer or portable workstation to run an examination of the hypothesis reenactment program. From the test information gotten, it can be concluded that the more noteworthy the frequency of the signal to be inspected, the closer the signal will be to the initial signal. The time and frequency of the examining signal are conversely relative. The higher the frequency, the lower the time will be. The magnitude of the amplitude of the output signal is indeterminate.
Phong Hung, Vu Duc Vuong
Published: 14 January 2021
Journal La Multiapp, Volume 1, pp 1-5; doi:10.37899/journallamultiapp.v1i6.277

Abstract:
The term digital signal is a term from a technology that converts an analog signal into digital data so that the signal can be processed more easily and quickly. The term digital itself is a system that only recognizes two conditions. The two conditions are usually represented by the numbers zero and one, on and off, or others. The smallest unit of digital signal is the bit.
Shiva Kumar Jha, Mahendra Tripathi, Balram Bhandari, Bhanu Pokharel, Tika Karki, Keshab Babu Koirala
Published: 31 December 2020
Journal La Multiapp, Volume 1, pp 1-9; doi:10.37899/journallamultiapp.v1i5.247

Abstract:
Uneven and low precipitation areas of Nepal are continuously suffering from drought and received low productivity because of unavailability of suitable drought tolerant maize genotype. An attempt has been made first time in Nepal by constructing an automated rainout shelter with soil moisture based automated drip irrigation system at National Maize Research Program in 2018-2019 to conduct an experiment on drought tolerant maize genotype. The rainout shelters automatically covers the cropping area as soon as the rain sensor received a single drop of precipitation and also if the light intensity decreased to value set in the control panel. Likewise, the soil water level in different treatments were maintained on the basis of the treatment controlled with automatic drip irrigation system set to irrigate at threshold value set in the microcontroller. The complete system had found very useful in determining accurate amount of water required to cultivate drought tolerant maize genotype. We have tested drought tolerant variety RampurSo3Fo8 under 10 level of irrigation and it was determined that 495.2 mm of water is maximum level of water to produce highest yield of 3.32 t/ha whereas 445.6 mm to 247.6 mm of water could can be manage to produce competitive yield without any reduction. An experiment under such kind of infrastructure provide useful information on irrigation management practices required for drought variety in the natural environment. The research output also guides farmers and agriculturist in making Nepalese agricultural more sustainable, mechanized and productive.
Que Duc Chinh, Bui Thuan Nguyen
Published: 31 December 2020
Journal La Multiapp, Volume 1, pp 10-16; doi:10.37899/journallamultiapp.v1i5.274

Abstract:
This article discusses the basics of the telecommunications system covering developments, working principles and emerging problems in telecommunications. The telecommunications system is all elements of both telecommunications infrastructure, equipment, facilities and infrastructure, as well as telecommunications operators, so that long-distance communication can be carried out. During the journey the information will pass through various media with different characteristics. So that it allows the occurrence of high delays and large packet loss, all of which will reduce the quality of the information received. The quality of the transmission medium determines the quality of the information received. Because as long as it is in the media, it is certain that the information will experience damping which will reduce the quality of the information. In order to communicate properly, the channel provided is not only physical media but also logical lines (frequency channels), considering that these frequency channels are expensive and limited.
Akramjon Mirzaev, Sanjar Zoteev
Published: 31 December 2020
Journal La Multiapp, Volume 1, pp 25-27; doi:10.37899/journallamultiapp.v1i5.275

Abstract:
This article discusses noise in telecommunications: different types and methods of dealing with noise. Noise is arguably a very hated problem because it can interfere with the quality of signal reception and also the reproduction of the signal that will be transmitted. Not only that, but noise can also limit the range of the system to a certain emission power and can affect the sensitivity and sensitivity of the reception signal. Even in some cases, noise can also result in a reduction in the bandwidth of a system. Of course, we've all felt how annoying the noise effect is. For example, when listening to the radio, a hissing sound appears on the loudspeaker due to noise. To overcome noise, it is divided into passive noise control and active noise control. Passive noise control is an effort to overcome noise using components that do not require power. Generally passive noise control uses soundproof materials that act as insulation against noise. The method most commonly used to overcome noise is through increasing the gain. The noise is generally in a specific sound area. Hiss is on high frequencies, while noise and hum are on low frequencies. This is the principle underlying the noise reduction method.
Samuel Ndidi, Victor Iwobi
Published: 31 December 2020
Journal La Multiapp, Volume 1, pp 17-19; doi:10.37899/journallamultiapp.v1i5.273

Abstract:
This article discusses processing in Image Interpolation and Motion Detection. Image or image has become a common thing and has become part of everyday people's life. In a particular interest, image is used as a tool to express various kinds of feelings which for some people are difficult to express through words. Such as explaining a reason, interpretation, illustration, communication, memory, education, evaluation, entertainment, and others. Then the concept of image and its processing is associated with changing and improving the image. Image is a representation, similarity, or imitation of an object or object, for example your photo represents the entity of yourself on camera. X-ray photographs of the chest represent the inside of a person's body, the data in a BMP file represents what it represents.
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