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Author(s):  
Arudra Annepu ◽  
◽  
Priti Mishra ◽  

Wireless network technically, refers to the category of network in which communication is carried out without using wires. In modern era wireless network has great importance because the communication is taking place with the use of radio waves. Thus, the use of ad-hoc network starts yielding a great importance in variety of applications. The certain research work is carried out in this particular field. MANET is a constructed from various mobility in the form of mobile nodes and anytime without any need of fixed infrastructure. MANET can be made on fly due to lack of fixed infrastructure. MANET is numerous threats types of attacks due to dynamic changing topologies and wireless medium. Security of the MANET becomes one of the challenging tasks. Black hole attacks is the main type of attack that are possible in MANET. Black hole node not forward any data packets to the neighbour node instead it drops all the data packets. Black hole attacks are bit hard to detect due to lack of centralized access. This research work concentrates to enhance the security of MANET by identifying and blocking black hole assaults from occurring. A reactive routing system such as Ad-Hoc on Demand Distance Vector has previously been used to address security problems in the MANET (AODV). Various attack types were investigated, and the consequences of these assaults were detailed by describing how MANET performance was disrupted. Network Simulator 3 (NS3) is used for the simulation process.


2022 ◽  
Vol 13 (1) ◽  
pp. 280-284
Author(s):  
Putri Aliya Ahadini ◽  
Muhamad Bagus Wira Utama ◽  
Adhyatma Ismu Reihan ◽  
Reny I’tishom

Mental disorders are one of the health disorders that contribute to high rates of disability and mortality worldwide. The current therapeutic modalities used to treat mental disorders are medical and psychological approaches, but it becomes problematic in some conditions, such as drug-resistant mental disorders. Radio Electric Asymmetric Conveyer (REAC) technology can be used as an alternative to overcome this problem. This technology uses radio waves which are guaranteed to be non-invasive and do not cause side effects. This technology enables neuromodulation effects by maximizing cell polarity and optimizing endogenous bioelectric activity. Of course, the REAC's mechanism as a neuromodulator and being a non-invasive technology is safe to use. It allows REAC to be used as an adjuvant therapy to reduce symptoms of several mental disorders such as depression, anxiety, bipolar disorder, phobias, and stress.


2022 ◽  
Vol 16 (2) ◽  
pp. 5-13
Author(s):  
A. S. Bazarova ◽  
R. S. Sychev ◽  
A. V. Bazarov ◽  
E. B. Atutov ◽  
Yu. B. Bashkuev

The values of the atmospheric refraction index N for ultra-short radio waves for the territory of Buryatia according to the data of meteorological stations were calculated. The monthly average values N contours maps for the central months of the seasons of 2020 were constructed. It is shown the humidity of Lake Baikal and the relief significantly influence N. On average, the values of the refractive index near the lake are 20–30 N-units higher. It is revealed the monthly average N values have maxima in winter and summer with minimums in spring and autumn, with the main maximum occurring in July.


2022 ◽  
Vol 8 (2) ◽  
pp. 339-346
Author(s):  
Edi Saputra Siregar

Storage for goods is an important part of a mosque. When we are going to pray in congregation, the items or bags we carry make us anxious and afraid of losing. The development of technology has replaced the storage of goods carried out by mosque officials into an automated storage system. But it also needs to be considered in terms of the security system for storing these items. Researchers formulate how automation and security systems use RRFID. The research method used is research and development. The storage of this item is programmed with the Arduino and CX Programmer applications by creating a security system using Radio Frequency Identification (RFID) as radio waves carrying data that will be received by the RFID reader. The result of this research is an automatic door prototype using RFID which will operate properly. Reader ability to detect id card very good starting when the card is affixed to the reader and the selenoid system will work to open the door when the id card is attached.


2022 ◽  
Vol 17 (01) ◽  
pp. C01050
Author(s):  
G. Torrisi ◽  
E. Naselli ◽  
L. Di Donato ◽  
G.S. Mauro ◽  
M. Mazzaglia ◽  
...  

Abstract Plasma diagnostics is a topic having a great impact on R&D in compact ion sources as well as in large fusion reactors. Towards this aim, non-invasive microwave diagnostics approaches, such as interferometric, polarimetric and microwave imaging profilometric techniques can allow obtaining volumetric, line-integrated or even space-resolved information about plasma electron density. Special probes can be also designed and implemented in order to characterize external and/or self-generated radio-waves in the plasmas. In particular, the design, construction and operation of a K-band microwave interferometry/polarimetry setup based on the Frequency-Modulated Continuous-Wave (FMCW) method at INFN-LNS will be described: this tool provides reliable measurements of the plasma density even in the extreme unfavorable wavelength-to-plasma scale ratio in plasma-based ion sources. A “frequency sweep” and a post-processing filtering method (for interferometry and polarimetry, respectively) were used to filter out the multipath contributions or cavity induced depolarizations in the detected signals. Besides this, the use of the aforementioned RF plasma-immersed probes will also be discussed, which allow measuring local E-fields and fast temporal response in order to characterize turbulent (through kinetic instabilities, cyclotron maser emission, etc.) vs. stable plasma regimes. An analysis based on wavelet transform applied to measurements of plasma radio self-emission in B-minimum and simple mirror traps will be presented. These tools and methods have the potential to be applied to plasma machines both in compact traps and large-size reactors with a proper scaling.


Author(s):  
Madhulika Bharti ◽  
Priyanka Bharti ◽  
Manindra Kumar ◽  
Prashant Kumar

Electromagnetic radio waves have been propagating for billions of years through the universe since the beginning of time. Electromagnetic radio wave propagation and the communication revolution it spawned, however are products of the twentieth century. Radio propagation in a particular environment is a complex, multipath phenomenon which involves several different mechanisms. According to a traditional, simplified approach, two  major urban propagation mechanisms are identified over-roof-top (ORT) or vertical propagation (VP), where one major radial path undergoes multiple diffractions on building tops, and lateral propagation (LP) where several rays reflect/diffract all vertical building walls/edges according to the geometrical Optics (GO) rules before reaching the receiver.


Author(s):  
V. M. Somsikov ◽  
I. P. Chunchuzov ◽  
A. Jahanshir ◽  
S. N. Mukasheva

The paper provides a review of studies devoted to the peculiarities of the propagation of radio waves in the ionosphere in the area of the solar terminator, which is the only global and regular source of acoustic-gravitational waves and other disturbances of the ionosphere. It describes the results of theoretical works devoted to the study of perturbations created by the solar terminator in the area of the difference in the intensity of solar radiation in the atmosphere. The paper gives a review of experimental studies of the effects created by the solar terminator in the entire thickness of the atmosphere. These effects, in particular, include the multipath propagation of radio waves, their phase variations, and variations in amplitudes during the propagation of radio waves in the area of the solar terminator. In the interests of science and practice, a number of problems have been proposed for the further study of wave perturbations arising as a result of the movement of the temperature gradient at sunrise and sunset hours.


2021 ◽  
Vol 3 (4) ◽  
pp. 279-289
Author(s):  
Vladimir Parkhomov ◽  
Aleksandr Mikhalev ◽  
Konstantin Ratovskyi

The research analyzed the regularities of the dynamics of geomagnetic pulsation regimes in the frequency range 0.002–5 Hz, the generation of which reflects the interaction with the Earth's magnetosphere of the solar filament ejected by a powerful solar flare of 3B. We compared the dynamics of the change in the types and modes of geomagnetic pulsations with the dynamics of the atmosphere glow in two spectral lines and the total ionospheric absorption of radio waves. The study developed a possible model of the observed phenomenon.


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Kaveti UmaMaheswari ◽  
Arjun Chakravarthi Pogaku ◽  
Dinh-Thuan Do ◽  
Anh-Tu Le ◽  
Munyaradzi Munochiveyi

With the given scope for new use cases and the demanding needs of future 6th generation (6G) wireless networks, the development of wireless communications looks exciting. The propagation medium has been viewed as a randomly behaving entity between the transmitter and the receiver since traditional wireless technology, degrading the quality of the received signal due to the unpredictable interactions of the broadcast radio waves with the surrounding objects. On the other hand, network operators could now manipulate electromagnetic radiation to remove the negative impacts of natural wireless propagation due to the recent arrival of reconfigurable intelligent surfaces (RIS) in wireless communications. According to recent findings, the RIS mechanism benefits nonorthogonal multiple access (NOMA), which can effectively deliver effective transmissions. For simple design, of RIS-NOMA system, fixed power allocation scheme for NOMA is required. The main system performance metric, i.e., outage probability, needs to be considered to look at the efficiency and capability of transmission mode relying on RIS and NOMA schemes, motivated by the potential of these developing technologies. As major performance metrics, we derive analytical representations of outage probability, and throughput and an accurate approximation is obtained for the outage probability. Numerical results are conducted to validate the exactness of the theoretical analysis. It is found that increasing the higher number of reflecting elements in the RIS can significantly boost the outage probability performance, and the scenario with only the RIS link is also beneficial. In addition, it is desirable to deploy the RIS-NOMA since it is indicated that better performance compared with the traditional multiple access technique.


Diagnostics ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 27
Author(s):  
Mio Adachi ◽  
Tsuyoshi Nakagawa ◽  
Tomoyuki Fujioka ◽  
Mio Mori ◽  
Kazunori Kubota ◽  
...  

Purpose: Microwave radar-based breast imaging technology utilizes the principle of radar, in which radio waves reflect at the interface between target and normal tissues, which have different permittivities. This study aims to investigate the feasibility and safety of a portable microwave breast imaging device in clinical practice. Materials and methods: We retrospectively collected the imaging data of ten breast cancers in nine women (median age: 66.0 years; range: 37–78 years) who had undergone microwave imaging examination before surgery. All were Japanese and the tumor sizes were from 4 to 10 cm. Using a five-point scale (1 = very poor; 2 = poor; 3 = fair; 4 = good; and 5 = excellent), a radiologist specialized in breast imaging evaluated the ability of microwave imaging to detect breast cancer and delineate its location and size in comparison with conventional mammography and the pathological findings. Results: Microwave imaging detected 10/10 pathologically proven breast cancers, including non-invasive ductal carcinoma in situ (DCIS) and micro-invasive carcinoma, whereas mammography failed to detect 2/10 breast cancers due to dense breast tissue. In the five-point evaluation, median score of location and size were 4.5 and 4.0, respectively. Conclusion: The results of the evaluation suggest that the microwave imaging device is a safe examination that can be used repeatedly and has the potential to be useful in detecting breast cancer.


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