ON THE PAPR REDUCTION IN OFDM SYSTEMS: A NOVEL ZCT PRECODING BASED SLM TECHNIQUE

High Peak to Average Power Ratio (PAPR) reduction is still an important challenge in Orthogonal Frequency Division Multiplexing (OFDM) systems. In this paper, we propose a novel Zadoff-Chu matrix Transform (ZCT) precoding based Selected Mapping (SLM) technique for PAPR reduction in OFDM systems. This technique is based on precoding the constellation symbols with ZCT precoder after the multiplication of phase rotation factor and before the Inverse Fast Fourier Transform (IFFT) in the SLM based OFDM (SLM-OFDM) Systems. Computer simulation results show that, the proposed technique can reduce PAPR up to 5.2 dB for N=64 (System subcarriers) and V=16 (Dissimilar phase sequences), at clip rate of 10-3. Additionally, ZCT based SLM-OFDM (ZCT-SLM-OFDM) systems also take advantage of frequency variations of the communication channel and can also offer substantial performance gain in fading multipath channels

PAPR REDUCTION IN LAYERED-OFDMA OF LTE-A: A NEW PRECODING BASED ADAPTIVE UPLINK RA SYSTEM

This paper presents a new precoding based adaptive multi-carrier/single-carrier (MC/SC) uplink radio-access (RA) system with improved peak-to-average power ratio (PAPR) for layered orthogonal frequency division multiple access (Layered-OFDMA) of long term evolution advanced (LTE-A). The Discrete-Cosine transform (DCT) precoding is applied before subcarrier mapping and IFFT to reduce the high PAPR of the MC uplink system. The conventional SC system is implemented to sustain all the functionalities offered by the release 8 LTE. Extensive computer simulations have been performed to analyze the PAPR of the proposed system. The computer simulation results show that, the PAPR of DCT precoded MC signals is approximately same as that of conventional SC signals

A NEW DISCRETE HARTLEY TRANSFORM PRECODING BASED INTERLEAVED-OFDMA UPLINK SYSTEM WITH REDUCED PAPR FOR 4G CELLULAR NETWORKS

High peak-to-average power ratio (PAPR) reduction is one of the major challenges in orthogonal frequency division multiple access (OFDMA) systems since last decades. High PAPR increases the complexity of analogue-to-digital (A/D) and digital-to-analogue (D/A) convertors and also reduces the efficiency of RF high-power-amplifier (HPA). In this paper, we present a new Discrete- Hartley transform (DHT) precoding based interleaved-OFDMA uplink system for PAPR reduction in the upcoming 4G cellular networks. Extensive computer simulations have been performed to analyze the PAPR of the proposed system with root-raised-cosine (RRC) pulse shaping. We also compare simulation results of the proposed system with the conventional interleaved-OFDMA uplink systems and the Walsh-Hadamard transform (WHT) precoding based interleaved-OFDMA uplink systems. It is concluded from the computer simulations that the proposed system has low PAPR as compared to the conventional interleaved-OFDMA uplink systems and the WHT precoded interleaved-OFDMA uplink systems

To study the prescription pattern of antibiotics in medicine intensive care unit at tertiary care hospital

Background: Drug utilization studies are crucial and create a positive awareness about proper use of drugs. Analysing the pattern of prescriptions is important in the settings of intensive care units where patients receive multiple antibiotics. The objective of this study was to analyse the use of antibiotics in a Medicine Intensive Care Unit (MICU) of Government Medical College and Hospital, Aurangabad, Maharashtra, India, a tertiary health care centre.Methods: Total 988 number of patients admitted in MICU from January 2017 to June 2018 were enrolled in the study and fulfilling inclusion criteria. Demographic details, disease state and prescription of antibiotic was recorded.Results: Out of 988, n=700 patients received antibiotics. Most common diseases for which patients were admitted in MICU included OP poisoning (24.86%), snake bite (15.14%), bilateral pneumonitis (12.71%), HELLP syndrome (12.14%), and the least common conditions were chronic obstructive pulmonary disease (COPD), meningitis, sepsis with multiple organ dysfunction syndrome (MODS), Guillen barre syndrome (GBS), lung abscess etc., Most common single antibiotic used in the studied cases was ceftriaxone (21.42%) followed by either alone or in combination piperacillin and tazobactam (12.04%), metronidazole (11.85%) etc.Conclusions: Total 700 patients received systemic antibiotics in present study bringing the incidence of systemic antibiotics use in MICU to be 70.85%. Ceftriaxone and combination of piperacillin and tazobactam are most commonly used antibiotics in MICU of the hospital. All patients admitted in this MICU received antibiotics as per the standard protocols of the hospital

Novel Precoding Based PAPR Reduction Schemes for Localized OFDMA Uplink of LTE-A

High Peak to Average Power Ratio (PAPR) reduction is still a major challenge in Orthogonal Frequency Division Multiple Access (OFDMA) systems. The subcarrier mapping in OFDMA can be done in two modes, Localized mode and Distributed mode. The Localized mode is more suitable for the practical implementations than the Distributed mode due to its low sensitivity against the imperfect power control, phase noise and Inter Carrier Interference (ICI). In this paper, we propose two novel precoding based Multi-Carrier (MC) Multiple Access (MA) techniques for PAPR reduction, ZadoffChu precoding based Localized-OFDMA (L-OFDMA) technique and Generalized Chirp Like (GCL) precoding based L-OFDMA technique for L-OFDMA uplink systems of upcoming Long Term Evaluation-Advanced (LTE-A) system. These techniques are based on precoding the constellation symbols with Zadoff-Chu precoder and GCL precoder. The proposed techniques can reduce PAPR up to 6.5dB for L-OFDMA. It is noticeable from the computer simulation results, that the PAPR of our proposed precoding based MC systems have approximately equal PAPR as compared to the PAPR of competing technology called Localized Single Carrier Frequency Division Multiple Access SC-FDMA (LFDMA) system. LFDMA is implemented in release 8 of Long Term Evaluation (LTE). Additionally, these precoding based PAPR reduction techniques also takes the advantage of the frequency variations of the communication channel and can also offer substantial performance gain in fading multipath channel

Harnessing Artificial Intelligence Capabilities to Improve Cybersecurity

Cybersecurity is a fast-evolving discipline that is always in the news over the last decade, as the number of threats rises and cybercriminals constantly endeavor to stay a step ahead of law enforcement. Over the years, although the original motives for carrying out cyberattacks largely remain unchanged, cybercriminals have become increasingly sophisticated with their techniques. Traditional cybersecurity solutions are becoming inadequate at detecting and mitigating emerging cyberattacks. Advances in cryptographic and Artificial Intelligence (AI) techniques (in particular, machine learning and deep learning) show promise in enabling cybersecurity experts to counter the ever-evolving threat posed by adversaries. Here, we explore AI\u27s potential in improving cybersecurity solutions, by identifying both its strengths and weaknesses. We also discuss future research opportunities associated with the development of AI techniques in the cybersecurity field across a range of application domains

On families of convex polytopes with constant metric dimension

AbstractLet G be a connected graph and d(x,y) be the distance between the vertices x and y. A subset of vertices W={w1,w2,…,wk} is called a resolving set for G if for every two distinct vertices x,y∈V(G), there is a vertex wi∈W such that d(x,wi)≠d(y,wi). A resolving set containing a minimum number of vertices is called a metric basis for G and the number of vertices in a metric basis is its metric dimension dim(G). A family G of connected graphs is a family with constant metric dimension if dim(G) is finite and does not depend upon the choice of G in G.In this paper, we study the metric dimension of some classes of convex polytopes which are obtained by the combinations of two different graph of convex polytopes. It is shown that these classes of convex polytopes have the constant metric dimension and only three vertices chosen appropriately suffice to resolve all the vertices of these classes of convex polytopes

Prescription pattern of antibiotics in neonatal intensive care unit of tertiary care hospital

Background: Recurrent and prolonged courses of antibiotics exposure have resulted in an increase in the prevalence of hospital acquired infections and antibiotic resistant profile. The objective of this study was to quantify the use of antibiotics in a neonatal intensive care unit (NICU) of Govt. Medical College and Hospital, Aurangabad, Maharashtra, a tertiary health care centre.Methods: A total of 260 neonates admitted in NICU from August 2017 to February 2018 were enrolled in the study and fulfilling inclusion criteria of the study. Demographic details, data on antibiotic prescriptions (name, dose, frequency, route of administration) was recorded on pre-tested structured Performa.Results: A total of 248 neonates received the antibiotics. EOS pneumonia was most common i.e. 29.8% followed by LOS pneumonia (20.6%). Sepsis, pneumonia Meningitis, NEC, were common indications for admission in NICU. Among the antibiotic combinations amoxicillin + clavulanate (38.99%), was most commonly prescribed followed by gentamicin (37.89%) and piperacillin (11.01%) respectively. Other antibiotics like, linezolide (0.94%), fluconazole (5.97%), meropenem (4.42%), vancomycine (0.77%) were also used less commonly in NICU. About fifty of the medicine prescribed were in compliance with the national list of essential medicines 2011.Conclusions: In tertiary care setup of NICU amoxicillin + clavulanate and gentamicin are most commonly used antibiotics in NICU. The study concludes that the antibiotic prescription pattern at NICU of our tertiary care hospital was found rational