A New Analytical Model for SIM–OFDM Contradicts the Previously Claimed Features

The Subcarrier Index Modulation OFDM (SIM–OFDM) appeared in 2009 promising a –3 dB transmitted power reduction without affecting the system performance. Therefore, it became an attractive choice to upgrade the communication systems with researchers’ increasing interest. Despite the research efforts in SIM–OFDM field, there was no in-depth investigation for such transmitted power reduction or the system’s performance. The claimed power reduction relies on probabilistic assumptions that were not validated considering system operation concepts. This paper provides a new analytical model that characterizes the actual SIM–OFDM behavior. The contribution of this model is the inclusion of the majority condition in the derivation of 1’s pmf which modifies the 1’s pmf into a complex nonlinear function that is always higher than 1/2. The new pmf effect upon the power reduction, synchronization, and the overall Bit Error Rate (BER) is investigated. The new analytical model shows that the –3 dB power reduction cannot be achieved. Also, no successful synchronization can be established unless extra subcarrier is added that will create a frame like communication system. Such scheme increases BER if the carrier is falsely detected creating a Frame Error Rate (FER) which might lead to serious problem

Upgrading SIM–OFDM Using a Threshold for Correct Operation with Analytical Proofs

A new upgrade to the SIM–OFDM is suggested to solve a critical problem that crashes the system even over noiseless channel. This problem is the interference of the zeros at the IFFT output with the BOOK\u27s zeros that confuses the receiver during demodulation which leads to BER accumulation. The suggested solution is to use a threshold to differentiate the data carried by the BOOK from the IFFT\u27s symbols. The new system is called Threshold SIM–OFDM (TSIM–OFDM). The mathematical analysis of TSIM–OFDM proves it operates normally and meets the theoretical bounds. The TSIM–OFDM preserves the probability of 1 equal to 1/2. This preservation comes from the direct connection of the ON/OFF switching bits to the subcarrier which overrides the majority condition. This new switching technique simplifies the system operation resulting in higher transmission speed and increased spectral and power efficiency. A simple approach to derive the BER for the SIM–OFDM is presented which proves that the SIM–OFDM will never reach zero BER level unlike the TSIM–OFDM. The simulation results show that the TSIM–OFDM BER reaches zero level and the output power is almost half of the OFDM. Adding the threshold will increase the transmitted power slightly and tends to decrease with the increase of IFFT length

Influence of Ectopic Beats on the Average, Maximum, and Minimum Heart Rates

Background: Heart rate metrics including the average heart rate, maximum heart rate, and minimum heart rate reflect the physiological condition of the heart. Clinically, determining the impact of ventricular and atrial ectopic beats on those three metrics is important because they indicate how hard the heart is working. Objective: To investigate the changes in heart rates of ventricular and atrial ectopic patients. Patients and Methods: In this study, data from 90 persons (30 with ventricular ectopic beats, 30 with atrial ectopic beats, and 30 healthy people) were gathered and analyzed to see what changes in heart rate metrics may occur in patients with ectopic beats. Results: According to our results, the three heart rate metrics in almost all three groups are statistically insignificant (p-value > 0.05). The average heart rate was significantly higher (p<0.05) in ventricular ectopic patients than in atrial ectopic patients. The effect of age and gender on heart rate metrics were statistically assessed. Conclusion: Despite the fact that no significant differences were found in all groups, there were certain differences that require further examination. One of the long-term objectives is to expand this study to incorporate electrocardiography (ECG) analysis in order to complete the comparison between the three groups

Short-term assessment of heavy metals in surface waters of the Shatt Al-Arab River

The Shatt Al-Arab River's water quality deteriorates naturally due to salinity intrusion, and freshwater sources decrease. Seven sampling locations along the Shatt Al-Arab River in southern Iraq were used to examine the level of six heavy metals, including Cu, Cd, Ni, Co, Mn, and Fe, during Januar-December 2021. Salinity levels in the study area ranged from 1.55 upstream to 35.15 g/L downstream of the study area. The pH of surface water ranged 7.545-8.325, indicating alkaline conditions. The concentrations of six heavy metals, viz Cu, Cd, Ni, Mn, Co, and Fe in the study area were 3.741±4.219, 3.654±4.169, 7.700± 6.251, 2.551±3.898, 2.292±3.996, and 18.236±5.583 µg/L, respectively, which decreased in the order of Fe &gt; Ni &gt; Cu &gt; Cd &gt; Mn &gt; Co. There was a considerable change in the quantity of heavy metals throughout the year, with the summer months having the highest concentration. There is a correlation between seawater intrusion and the concentration of heavy metals in the surface waters. The mean levels of the heavy metals were below the allowed values of WHO drinking water guidelines

FINGERPRINT IDENTIFICATION TECHNIQUE BASED ON WAVELET-BANDS SELECTION FEATURES (WBSF) IJCET © I A E M E

ABSTRACT The paper is concerned with the use of fingerprint (FP)features for protection against unauthorized access. Wavelet features for both closed and open-set FP recognition are studied here to verify persons&apos; identity. Fingerprints of 49 persons (32-authorized and 17-unauthorized) were taken as testing data. Each authorized person is asked to give 10-instances of his right forefinger print. In the closed-set FP recognition, the obtained recognition rates are below 90% due to the imperfections in the FP images that negatively affect the recognition rate. Preprocessing operations such as: noise-removal, segmentation, normalization and binarization are considered to improve the resulting recognition rates. A method that relies on a new selection process for wavelet decomposition bands is proposed, which enhance the recognition rates further to get about 100% in some favorable conditions. The results have shown that the wavelet descriptors using the proposed Wavelet-Bands Selection Features (WBSF) are efficient representation that can provide reliable recognition for large input variability. The open-set FP verification mode is also presented for 290 trials from 29 persons, where the obtained verification rates are greater than 97% for both Euclidean and city-block distance measures

Virulence surveillance of wheat black stem rust fungus

General survey for wheat rust diseases in Iraqi fields was done during the seasons of 2010, 2011 and 2012. The survey covered different fields in southern, middle and northern regions. Results of the first season indicated that most of Iraqi cultivars such as Tmmoze2, IPA 99 and Mexipak showed different types of susceptibility to both yellow and leaf rust infection. Disease severity increased when the conditions were favorable for infections with using susceptible cultivars. The severity of leaf rust was less in the north region comparing with the middle and south regions. Most of the introduced cultivars such as Sham6 and Cimmyto showed susceptible reaction to yellow and leaf rust. Yellow rust was in epiphytotic form at the Iraqi-Syrian-Turkish triangle where the disease severity was 100%. Low disease severity of stem rust was observed on some cultivars (1-5%), except for the cultivar Mexipak which showed 40%S in Najaf. Rusts at season of 2011 were restricted mostly in Baghdad and the yellow rust was dominant. The AUDPC of 15 wheat cultivars showed that Sawa and Sali were highly susceptible to the three types of rusts while Babil113 and Tamoze2 were resistant. No rusts were detected at season 2012