DESIGN AND PERFORMANCE ANALYSIS OF VCO FOR STANDARD GSM USING MEMS

The design of a prototype monolithic Micro Electro-Mechanical Systems (MEMS) electronic circuits, namely the Voltage Controlled Oscillators (VCOs) is presented. The components can achieve the stringent requirements of wireless communication applications such as GSM cellular telephony. The VCO meets the low phase noise specifications of -136 dBc/Hz at large offset frequency of 3MHz, over the appropriate frequency range. The model of the monolithic VCO is based on the topology of the Colpitts Oscillator. It is relatively less complicated, which facilitates the practical integration of the MEMS components into the configuration. The variable capacitor and the monolithic 3-D coil inductor are suitable for low phase-noise and low power consumption at the application frequencies. A PSpice simulation model was developed with MEMS switching devices that can be integrated into the system. The model helps in determining the design parameters, which affect the performance and operation reliability of the RF transceiver system, for which a prototype has been tested and proved successful

Familial hypercholesterolaemia in children and adolescents from 48 countries: a cross-sectional study

Background: Approximately 450 000 children are born with familial hypercholesterolaemia worldwide every year, yet only 2·1% of adults with familial hypercholesterolaemia were diagnosed before age 18 years via current diagnostic approaches, which are derived from observations in adults. We aimed to characterise children and adolescents with heterozygous familial hypercholesterolaemia (HeFH) and understand current approaches to the identification and management of familial hypercholesterolaemia to inform future public health strategies. Methods: For this cross-sectional study, we assessed children and adolescents younger than 18 years with a clinical or genetic diagnosis of HeFH at the time of entry into the Familial Hypercholesterolaemia Studies Collaboration (FHSC) registry between Oct 1, 2015, and Jan 31, 2021. Data in the registry were collected from 55 regional or national registries in 48 countries. Diagnoses relying on self-reported history of familial hypercholesterolaemia and suspected secondary hypercholesterolaemia were excluded from the registry; people with untreated LDL cholesterol (LDL-C) of at least 13·0 mmol/L were excluded from this study. Data were assessed overall and by WHO region, World Bank country income status, age, diagnostic criteria, and index-case status. The main outcome of this study was to assess current identification and management of children and adolescents with familial hypercholesterolaemia. Findings: Of 63 093 individuals in the FHSC registry, 11 848 (18·8%) were children or adolescents younger than 18 years with HeFH and were included in this study; 5756 (50·2%) of 11 476 included individuals were female and 5720 (49·8%) were male. Sex data were missing for 372 (3·1%) of 11 848 individuals. Median age at registry entry was 9·6 years (IQR 5·8-13·2). 10 099 (89·9%) of 11 235 included individuals had a final genetically confirmed diagnosis of familial hypercholesterolaemia and 1136 (10·1%) had a clinical diagnosis. Genetically confirmed diagnosis data or clinical diagnosis data were missing for 613 (5·2%) of 11 848 individuals. Genetic diagnosis was more common in children and adolescents from high-income countries (9427 [92·4%] of 10 202) than in children and adolescents from non-high-income countries (199 [48·0%] of 415). 3414 (31·6%) of 10 804 children or adolescents were index cases. Familial-hypercholesterolaemia-related physical signs, cardiovascular risk factors, and cardiovascular disease were uncommon, but were more common in non-high-income countries. 7557 (72·4%) of 10 428 included children or adolescents were not taking lipid-lowering medication (LLM) and had a median LDL-C of 5·00 mmol/L (IQR 4·05-6·08). Compared with genetic diagnosis, the use of unadapted clinical criteria intended for use in adults and reliant on more extreme phenotypes could result in 50-75% of children and adolescents with familial hypercholesterolaemia not being identified. Interpretation: Clinical characteristics observed in adults with familial hypercholesterolaemia are uncommon in children and adolescents with familial hypercholesterolaemia, hence detection in this age group relies on measurement of LDL-C and genetic confirmation. Where genetic testing is unavailable, increased availability and use of LDL-C measurements in the first few years of life could help reduce the current gap between prevalence and detection, enabling increased use of combination LLM to reach recommended LDL-C targets early in life

Algorithm of Face Recognition by Principal Component Analysis

A face recognition algorithm based on Principal Component Analysis (PCA) has been developed and tested for computer vision applications. A database of about 400 facial images was used to test the algorithm. Each image is represented by a matrix (112 x 92), The data base is divided into subsets, where each subset represents one of 10 different individuals. A 96% rate of successful detection and a 90% rate of successful recognition were obtained. Several factors had to be standardized to provide a constrained environment in order to reduce error. The analysis is based on a set of eigenvectors that defines an Eigen Face (EF). The method proved to be simple and effective. The simplified algorithm and techniques expedited the process without seriously compromising the accuracy

5.5-10.5 GHz IR-UWB Pulse Generator for Narrowband Interference Mitigation

An impulse radio ultra wideband (IR-UWB) pulse generator works between 5.5-10.5 GHz for narrowband interference mitigation is proposed. With an average power of -85 dBm/MHz from 0-5 GHz, high interference avoidance has been achieved for a wide range of narrowband systems including Global Positioning System (GPS), Worldwide Interoperability for Microwave Access (WiMAX), Wireless Local Area Network (WLAN) 802.11b and 802.11a. The proposed pulse generator utilizes a 1 GHz sine wave power source to work with the designed half-wave rectifier. The generated pulse width is less than 1 ns, providing a speed of about 1 Gb/s for IR-UWB system with minimum modulation complexity. A passive low pass filter (LPF) is designed with a cutoff frequency of 1.5 GHz works with the circuit up-converter mixer to generate a pulse which matches the Federal Communication Commission (FCC) requirements of UWB. The design has been carried out using Advanced Design System (ADS) software. The proposed pulse generator is supported by different modulation techniques like on-off keying (OOK) and pulse position modulation (PPM)

An emergency medical care network system for fetal ECG monitoring

Developing and less developing countries (LDCs) are identified in risk of stillbirth due to insufficient emergency medical take-care supports. The regular check-up of the fetal electrocardiography (FECG) could be an earliest prevention of this occurrence. This paper presents a research work aim to implement a simple, customize and portable emergency medical care for the FECG monitoring system from remote location. After acquisitions of the abdominal wall fetal electrocardiography (AFECG) signal from the pregnant mother (patient), the local terminal then transfers this AFECG signal as data to the remote terminal at the expert physician for diagnosis purpose. At the remote terminal, the FECG signals are then extracted from the AFECG signals by our developed software. In this case, computer network establishes a bridge between the patient and a distant expert physician. The network program developed based on the client/server applications. The developed network program is capable to support both the AFECG data transfer and online chat session simultaneously. A specialist physician at the remote terminal can diagnose the FECG signal and provides instruction to the local terminal in case of emergency. A number of cases studied by this developed system and found approximately same result compared with a commercial system