Millimeter-Wave CMOS Digitally Controlled Oscillators for Automotive Radars

All-Digital-Phase-Locked-Loops (ADPLLs) are ideal for integrated circuit implementations and effectively generate frequency chirps for Frequency-Modulated-Continuous-Wave (FMCW) radar. This dissertation discusses the design requirements for integrated ADPLL, which is used as chirp synthesizer for FMCW automotive radar and focuses on an analysis of the ADPLL performance based on the Digitally-Controlled-Oscillator (DCO) design parameters and the ADPLL configuration. The fundamental principles of the FMCW radar are reviewed and the importance of linear DCO for reliable operation of the synthesizer is discussed. A novel DCO, which achieves linear frequency tuning steps is designed by arranging the available minimum Metal-Oxide-Metal (MoM) capacitor in unique confconfigurations. The DCO prototype fabricated in 65 nm CMOS fullls the requirements of the 77 GHz automotive radar. The resultant linear DCO characterization can effectively drive a chirp generation system in complete FMCW automotive radar synthesizer

A SigmaDelta modulator for digital hearing instruments using 0.18 mum CMOS technology.

This thesis develops the design methodology for a low-voltage low-power SigmaDelta Modulator, realized using a switched op-amp technique that can be used in a hearing instrument. Switched op-amp implementation allows scaling down the design to the latest CMOS technology. A single-loop second-order SigmaDelta Modulator topology is chosen. The modulator circuit features reduced complexity, area reduction and low conversion energy. The modulator has a sampling rate of 8.2 MHz with an over-sampling ratio (OSR) of 256 to provide an audio bandwidth of 16 kHz. The modulator is implemented in a 0.18 mum digital CMOS technology with metal-to-metal sandwich structure capacitors. The modulator operates with a supply voltage of 1.8 V. The active area is 0.403 mm2. The modulator achieves a 98 dB signal-to-noise-and-distortion ratio (SNDR) and a 100 dB dynamic range (DR) at a Nyquist conversion rate of 32 kHz and consumes 1321 muW with a joule/conversion figure of merit equal to 161 x 10-12 J/s. The design methodology is developed through the extensive use of simulation tools. The behaviour simulation is carried out using Matlab/SIMULINK while circuits are simulated with Hspice using the Cadence design tools. Full-custom layout for the analog and the digital circuits is performed using the Cadence design tool. Post-processing simulation of the extracted modulator with parasitic verifies that results meet the requirements. The design has been sent to CMC for fabrication. Source: Masters Abstracts International, Volume: 43-03, page: 0947. Adviser: W. C. Miller. Thesis (M.A.Sc.)--University of Windsor (Canada), 2004

Knowledge and application of biological control in oil palm plantations : Survey in Merlimau and Jasin, Melaka / Nurfariha Iman Taha

Oil Palm are widely grown in tropical countries especially in Malaysia. The widespread use of this pesticide and insecticide chemical is causing the new bad effect to the environment and human health such as secondary pest outbreaks, resistance and hazards. They started using natural materials such using a biological control application to control the pest populations in the plantations. Biological control is the natural way that is aimed to pests and diseases. Biological control agent is the form of predators, parasitoids and pathogen. By doing this survey study, the existing knowledge of biological control among the managers and small holders of the oil palm plantation will be investigate. Furthermore, this survey indirectly help the managers and smallholders know the pro and cons of biological application compares to the using of chemical in their field. Besides, there have a different between the plantations which apply and without applying the biological control to reduce the pests and diseases

Employing Hot-Melt Extrusion Technology to Enhance the Solubility of Cannabidiol (CBD)

Corresponding author (Pharmaceutics and Drug Delivery): Iman Taha, [email protected]://egrove.olemiss.edu/pharm_annual_posters_2022/1020/thumbnail.jp

The Impact of the COVID-19 Pandemic on Female Sexual Function in Jordan: Cross-sectional Study.

BackgroundSexual function is a complex physiological process controlled by neurovascular and endocrine mechanisms that are affected by stressful events. The sexual response cycle consists of four main phases, which are sexual desire or libido, arousal or excitement, orgasm, and resolution. The COVID-19 outbreak is one of the most stressful events historically, causing several unpleasant consequences, including major physical and mental disorders, and sexual dysfunction and alteration in sexual behavior are possible anticipated consequences of the pandemic. Moreover, there are social taboos related to sexual behavior in Jordan, and the current knowledge on changes in Jordanian female sexual function during COVID-19 pandemic is limited.ObjectiveThis study aims to evaluate the impact of COVID-19 on women's sexual function during the early COVID-19 pandemic in Jordan.MethodsThis is a cross-sectional study that employed a web-based survey to follow 200 female individuals from the general population in Jordan. The survey evaluated sexual function both during COVID-19 and 6 months prior to the pandemic. The primary outcomes investigated in this study were the changes in sexual intercourse frequency and sexual function aspects, including desire, arousal, satisfaction, orgasm, lubrication, and pain during sexual activity. Data were analyzed using paired t test, McNemar test, Pearson correlations, and multiple linear regression using SPSS 25.ResultsDuring the COVID-19 pandemic, the participants' sexual intercourse frequency increased while their sexual satisfaction was significantly changed. The proportion of participants who had 0-2 times per week of sexual intercourse was decreased during the COVID-19 pandemic compared with that before the pandemic (n=90, 45% vs n=103, 51.5%; P=.02). Conversely, the number of female individuals with 3-7 times per week of sexual intercourse increased after the pandemic compared with the prepandemic state (n=103, 51.5% vs n=91, 45.5%; P=.04). Female sexual satisfaction was significantly reduced after the COVID-19 pandemic compared with that before the pandemic (3.39 vs 3.30; P=.049). The other categories of sexual function, including desire, arousal, satisfaction, orgasm, lubrication, and dyspareunia showed no significant changes during the COVID-19 pandemic compared with the previous 6 months. There were no significant differences between the total sexual function mean scores during COVID-19 (15.73) compared with the prepandemic scores (15.85; P=.41). The total score of female sexual function during the pandemic was negatively associated with the participants' age and education level. Correlations between various demographics and sexual function categories during the COVID-19 pandemic were identified.ConclusionsThis is the first study exploring female sexual function during the COVID-19 outbreak in Jordan. The results suggest that COVID-19-associated stress is influencing women's sexual function, necessitating the provision of adequate emotional and physiological well-being support for women during similar crises

Secure wireless sensor network using cryptographic technique based hybrid genetic firefly algorithm

Wireless sensor networks (WSNs) are formed of self-contained nodes of sensors that are connected to one base station or more. WSNs have several primary aims one of them is to transport network node's trustworthy information to another one. As WSNs expand, they become more vulnerable to attacks, necessitating the implementation of strong security systems. The identification of effective cryptography for WSNs is a significant problem because of the limited energy of the sensor nodes, compute capability, and storage resources. Advanced Encryption Standard (AES) is an encryption technique implemented in this paper with three meta-heuristic algorithms which are called Hybrid Genetic Firefly algorithm, Firefly algorithm, and Genetic algorithm to ensure that the data in the WSNs is kept confidential by providing enough degrees of security. We have used hybrid Genetic firefly as a searching operator whose goal is to improve the searchability of the baseline genetic algorithm. The suggested framework's performance that based on the algorithm of hybrid genetic firefly is rated by using Convergence Graphs of the Benchmark Functions. From the graphs we have conclude that hybrid genetic firefly with AES is best from other algorithms

Screening for psychological distress among High School Graduates Accepted for Enrollment at Alexandria Faculty of Medicine: Academic year 2016/2017

Background: Mental and psychological health of adolescents in general and prospective medical students in particular is a priority area to investigate as it affects wellbeing of the future doctors.Objectives: The current research was conducted to screen first year medical students accepted for enrollment at Alexandria Faculty of Medicine to identify those with a high probability of having psychological distress before the start of academic courses as well as explore the sources of stress among them.Methods: A cross sectional survey of 779 high school graduates accepted for admission to Alexandria Faculty of medicine was conducted. Participants were approached on the days of obligatory pre-enrollment medical examination. The translated Arabic version of DASS 21 questionnaire was used to screen students for three negative emotional symptoms namely depression, anxiety and stress. Inquiry about age, sex, residency and type of high school was added.Results: More than a tenth of studied medical students (12.6%) suffered from severe or profound stress and 29.1% of them had mild to moderate stress. Moreover, one fifth (20%) of studied students were severely anxious and less than one third (29.3%) had mild to moderate anxiety. Severe and profound depression was diagnosed among 14.3% of students whereas, 18.7% them were moderately depressed. No association was found between any of studied negative emotional symptoms and the students’ educational background or their residency.Conclusion: Nearly half of the prospective medical students might have some sort of psychological distress before starting their study in the Faculty of Medicine. They should be investigated to verify diagnosis and start intervention to minimize its adverse effects on academic performance and advancement at the faculty. Stress management courses should be considered for all medical students.Keywords: Psychological distress, Prospective medical students, Adolescents’ psychological health, Depression, Anxiety, Stres

Strength and deformability of waste tyre rubber-filled reinforced concrete columns

This study aims to investigate the efficiency of waste tyre rubber-filled concrete to improve the deformability and energy absorption capacity of RC columns by considering different concrete compressive strength, size of waste tyre rubber particles and rubber content. Twelve column specimens were tested using concrete of compressive strength 24 and 28 MPa mixed with 0.6 and 1 mm tyre rubber particles. For each concrete batch, 27 control specimens were prepared to examine the concrete properties. Using waste tyre rubber-filled concrete leads to a slightly lower compressive strength and modulus of elasticity, but the curvature ductility can increase up to 90%. It is concluded that this type of concrete can offer good energy dissipation capacity and ductility, which makes it suitable for seismic applications

Choline-Based Ionic Liquids-Incorporated IRMOF-1 for H2S/CH4 Capture: Insight from Molecular Dynamics Simulation

The removal of H2S and CH4 from natural gas is crucial as H2S causes environmental contamination, corrodes the gas stream pipelines, and decreases the feedstock for industrial productions. Many scientific researches have shown that the metal-organic framework (MOF)/ionic liquids (ILs) have great potential as alternative adsorbents to capture H2S. In this work, molecular dynamics (MD) simulation was carried out to determine the stability of ILs/IRMOF-1 as well as to study the solubility of H2S and CH4 gases in this ILs/IRMOF-1 hybrid material. Three choline-based ILs were incorporated into IRMOF-1 with different ratios of 0.4, 0.8, and 1.2% w/w, respectively, in which the most stable choline-based ILs/IRMOF-1 composite was analysed for H2S/CH4 solubility selectivity. Among the three choline-based ILs/IRMOF-1, [Chl] [SCN]/IRMOF-1 shows the most stable incorporation. However, the increment of ILs loaded in the IRMOF-1 significantly reduced the stability of the hybrid due to the crowding effect. Solvation free energy was then computed to determine the solubility of H2S and CH4 in the [Chl] [SCN]/IRMOF-1. H2S showed higher solubility compared to CH4, where its solubility declined with the increase of choline-based IL loading