Peak-Age Violation Guarantees for the Transmission of Short Packets over Fading Channels

We investigate the probability that the peak age of information in a point-to-point communication system operating over a multiantenna wireless fading channel exceeds a predetermined value. The packets are scheduled according to a last-come first-serve policy with preemption in service, and are transmitted over the channel using a simple automatic repetition request protocol. We consider quadrature phase shift keying modulation, pilot-assisted transmission, maximum-likelihood channel estimation, and mismatched scaled nearest-neighbor decoding. Our analysis, which exploits nonasymptotic tools in information theory, allows one to determine, for a given information packet size, the physical layer parameters such as the SNR, the number of transmit and receive antennas, the amount of frequency diversity to exploit, and the number of pilot symbols, to ensure that the system operates below a target peak-age violation probability.Comment: 6 pages, 6 figures. To be presented at Infocom 201

Low-Latency Short-Packet Transmissions: Fixed Length or HARQ?

We study short-packet communications, subject to latency and reliability constraints, under the premises of limited frequency diversity and no time diversity. The question addressed is whether, and when, hybrid automatic repeat request (HARQ) outperforms fixed-blocklength schemes with no feedback (FBL-NF) in such a setting. We derive an achievability bound for HARQ, under the assumption of a limited number of transmissions. The bound relies on pilot-assisted transmission to estimate the fading channel and scaled nearest-neighbor decoding at the receiver. We compare our achievability bound for HARQ to stateof-the-art achievability bounds for FBL-NF communications and show that for a given latency, reliability, number of information bits, and number of diversity branches, HARQ may significantly outperform FBL-NF. For example, for an average latency of 1 ms, a target error probability of 10^-3, 30 information bits, and 3 diversity branches, the gain in energy per bit is about 4 dB.Comment: 6 pages, 5 figures, accepted to GLOBECOM 201

Capacity bounds for MIMO microwave backhaul links affected by phase noise

We present bounds and a closed-form high-SNR expression for the capacity of multiple-antenna systems affected by Wiener phase noise. Our results are developed for the scenario where a single oscillator drives all the radio-frequency circuitries at each transceiver (common oscillator setup), the input signal is subject to a peak-power constraint, and the channel matrix is deterministic. This scenario is relevant for line-of-sight multiple-antenna microwave backhaul links with sufficiently small antenna spacing at the transceivers. For the 2 by 2 multiple-antenna case, for a Wiener phase-noise process with standard deviation equal to 6 degrees, and at the medium/high SNR values at which microwave backhaul links operate, the upper bound reported in the paper exhibits a 3 dB gap from a lower bound obtained using 64-QAM. Furthermore, in this SNR regime the closed-form high-SNR expression is shown to be accurate.Comment: 10 pages, 2 figures, to appear in IEEE Transactions on Communication

Knowledge on respectful maternity care among staff nurses: a descriptive survey

Background: Pregnancy is an especial, rousing and often blissful period in a woman’s life. Women may undergo various physiological changes during antepartum, intrapartum and postpartum period. The birthing room environment and health care provider’s attitude are important to minimize the pain and offer a positive childbirth experience. Across the world, women endure disrespect and abuse (D&A) during childbirth. Dearth of Respectful Maternity Care (RMC) from medical professionals like doctors and midwives may cause patients to feel unsatisfied with the healthcare system and lessen their obligation to seek antenatal (ANC), delivery, and postnatal care services. Objective of the study was to assess the existing knowledge on RMC among staff nurses working in the labour room. Methods: A non-experimental descriptive survey design was used to assess the knowledge on Respectful Maternity Care among staff nurses working in the labour room. Non-probability convenient technique was used to select 69 staff nurses from Ramaiah Medical College Hospital, Ramaiah Memorial Hospital, Motherhood Hospital, Lakshmi Maternity and Surgical Center and Aveksha Hospital, Bengaluru from April 2022 to May 2022. Structured knowledge questionnaire was used to assess the knowledge on respectful maternity care. Results: The overall knowledge score shows that 65.5% had moderately adequate knowledge on Respectful Maternity Care. The overall knowledge score mean was 16.72 with mean percentage of 64.30 and SD of ±3.438. Conclusions: Assessment and improvement in nurses’ knowledge will improve the quality of care as a means of enhancing safety during childbirth and positive childbirth experience

Concentration in Knowledge Output: A case of Economics Journals

This paper assesses the degree of author concentration in seven economics journals, which were published in India during 1990-2002. To measure the degree of author concentration, Lotka's Law was used. Moreover, we also make an exploratory analysis of the geographic, economics subfield and institutional concentration in 704 economics journals. An important finding of this paper is that specialized journals in the sample report the highest degree of author concentration. This result is quite similar to the findings by Cox and Chung (1991). Furthermore, there are several instances showing that the journals lean towards certain norms; this may affect the flow of innovative ideas into economics. We conclude that a knowledge activity, involving the high degree of concentration and a biased publication process, may affect the flow of new ideas into the discipline.Concentration, Lotka's Law

Hydrobiological features of the Kerala backwaters during premonsoon and monsoon months

The hydrobiological features like temperature, salinity, phytoplankton, zooplankton and bottom fauna at twelve stations in the Vembanad lake during pre-monsoon and monsoon months were studied and the results communicated in this paper

Reliable Transmission of Short Packets through Queues and Noisy Channels under Latency and Peak-Age Violation Guarantees

This work investigates the probability that the delay and the peak-age of information exceed a desired threshold in a point-to-point communication system with short information packets. The packets are generated according to a stationary memoryless Bernoulli process, placed in a single-server queue and then transmitted over a wireless channel. A variable-length stop-feedback coding scheme---a general strategy that encompasses simple automatic repetition request (ARQ) and more sophisticated hybrid ARQ techniques as special cases---is used by the transmitter to convey the information packets to the receiver. By leveraging finite-blocklength results, the delay violation and the peak-age violation probabilities are characterized without resorting to approximations based on large-deviation theory as in previous literature. Numerical results illuminate the dependence of delay and peak-age violation probability on system parameters such as the frame size and the undetected error probability, and on the chosen packet-management policy. The guidelines provided by our analysis are particularly useful for the design of low-latency ultra-reliable communication systems.Comment: To appear in IEEE journal on selected areas of communication (IEEE JSAC

Setting the Children’s Teeth on Edge? The Influence of Parental Alcoholism on Children’s Wellbeing

The research on the impact of alcoholism on the family indicates that alcoholism often poses threat to the wellbeing of the family, the most affected ones being the other spouse and the children. Alcoholism often poses serious risk to the emotional, cognitive, behavioural, physical and social wellbeing of the abuser, the partner and the children. Most of the researches have explored the impact of parental alcoholism on the negative outcome on psychosocial development of partners and children, very few documented studies have been carried out on the positive aspects of life such as wellbeing and futuristic hope in the children of alcoholic parents (COA). This study attempts to explore the relationship and the difference between QOL and Hope in COA and children of non-alcoholics (CONA). The study was conducted on a sample of 60 children each between the age of 12 to 15 from alcoholics and non-alcoholic parents drawn from a district of Kerala using purposive sampling technique. The measures used were QOL-BREF by WHO (1996) and Children Hope Scale (CHS) by Snyder et al. (1996). The data was first analyzed using the descriptive statistics, the normality of the data was checked using Shapiro Wilk test, Mann-Whitney U test was used to find the difference between the COA and CONA on QOL and Hope. The relationship between the variables was assed using Spearman rank correlation. The results of the study indicate that there is significant difference in QOL among the children of alcoholics and non-alcoholics. The COA demonstrated comparatively less Hope than the CONA, however there was no significant difference among them. The QOL and Hope were correlated only among the CONA. The study has implication for positive intervention for the COA, parental and school based interventions such as preventive, remedial and holistic counselling or therapy

Peak-Age Violation Guarantees for the Transmission of Short Packets over Fading Channels

We investigate the probability that the peak age of information in a point-to-point communication system operating over a multiantenna wireless fading channel exceeds a predetermined value. The packets are scheduled according to a last-come first-serve policy with preemption in service, and are transmitted over the channel using a simple automatic repetition request protocol. We consider quadrature phase shift keying modulation, pilot-assisted transmission, maximum-likelihood channel estimation, and mismatched scaled nearest-neighbor decoding. Our analysis, which exploits nonasymptotic tools in information theory, allows one to determine, for a given information packet size, the physical layer parameters such as the SNR, the number of transmit and receive antennas, the amount of frequency diversity to exploit, and the number of pilot symbols, to ensure that the system operates below a target peak-age violation probability