Optimal inverter logic gate using 10-nm double gate-all-around (DGAA) transistor with asymmetric channel width

We investigate the electrical characteristics of a double-gate-all-around (DGAA) transistor with an asymmetric channel width using three-dimensional device simulation. The DGAA structure creates a siliconnanotube field-effect transistor (NTFET) with a core-shell gate architecture, which can solve the problem of loss of gate controllability of the channel and provides improved short-channel behavior. The channel width asymmetry is analyzed on both sides of the terminals of the transistors, i.e., source and drain. In addition, we consider both n-type and p-type DGAA FETs, which are essential to forming a unit logic cell, the inverter. Simulation results reveal that, according to the carrier types, the location of the asymmetry has a different effect on the electrical properties of the devices. Thus, we propose the N/P DGAA FET structure with an asymmetric channel width to form the optimal inverter. Various electrical metrics are analyzed to investigate the benefits of the optimal inverter structure over the conventional inverter structure. Simulation results show that 27% delay and 15% leakage power improvement are enabled in the optimum structure.ope

Metal Surface Guided-Wireless Power Transfer System for Portable Applications With Multiple Receivers

Recently, research has been actively conducted to overcome various challenges observed in wireless power transfer (WPT) technology. However, as additional techniques are implemented, the complexity and cost of WPT systems increased. Therefore, there is a need for a new WPT method that can overcome the shortcomings of existing technology. This paper presents a metal surface guided-wireless power transfer (MSG-WPT) system for applications with multiple receivers (Rxs). First, a plate-wire propagation enhancer (PWPE) is shown to improve the power transfer efficiency (PTE). However, it is not suitable for portable receiving systems. Based on our analysis of the PWPE characteristics, applying an L-section lumped impedance-matching scheme instead of a PWPE can improve the portability of the Rx. A coil-based propagation enhancer (CPE), or a coil-based inductor (CI), can increase the power received if it replaces the lumped inductor in the L-section scheme. The MSG-WPT system does not experience the co-alignment issues that exist between a pair of transceivers (TRxs) in conventional WPT systems. It can also support multiple Rxs while ensuring that the PTE of each Rx is relatively unaffected. An electromagnetic simulation of the proposed MSG-WPT system is performed using a high-frequency structure simulator (HFSS), and measurements are conducted in a corresponding experimental environment. The system power efficiency is measured at -12 dB in the 4 MHz frequency band. The proposed MSG-WPT system with a CPE is adequately efficient and portable, while also allowing a more liberal arrangement of Rxs compared to other conventional WPT systems

Subcutaneously implantable electromagnetic biosensor system for continuous glucose monitoring

Continuous glucose monitoring systems (CGMS) are becoming increasingly popular in diabetes management compared to conventional methods of self-blood glucose monitoring systems. They help understanding physiological responses towards nutrition intake, physical activities in everyday life and glucose control. CGMS available in market are of two types based on their working principle. Needle type systems with few weeks lifespan (e.g., enzyme-based Freestyle Libre) and implant type system (e.g., fluorescence-based Senseonics) with few months of lifespan are commercially available. An alternate to both working methods, herein, we propose electromagnetic-based sensor that can be subcutaneously implanted and capable of tracking minute changes in dielectric permittivity owing to changes in blood glucose level (BGL). Proof-of-concept of proposed electromagnetic-based implant sensor has been validated in intravenous glucose tolerance test (IVGTT) conducted on swine and beagle in a controlled environment. Sensor interface modules, mobile applications, and glucose mapping algorithms are also developed for continuous measurement in a freely moving beagle during oral glucose tolerance test (OGTT). The results of the short-term (1 h, IVGTT) and long-term (52 h, OGTT) test are summarized in this work. A close trend is observed between sensor frequency and BGL during GTT experiments on both animal species

Experimental Realization of Zenneck Type Wave-based Non-Radiative, Non-Coupled Wireless Power Transmission

A decade ago, non-radiative wireless power transmission re-emerged as a promising alternative to deliver electrical power to devices where a physical wiring proved impracticable. However, conventional "coupling-based" approaches face performance issues when multiple devices are involved, as they are restricted by factors like coupling and external environments. Zenneck waves are excited at interfaces, like surface plasmons and have the potential to deliver electrical power to devices placed on a conducting surface. Here, we demonstrate, efficient and long range delivery of electrical power by exciting non-radiative waves over metal surfaces to multiple loads. Our modeling and simulation using Maxwell's equation with proper boundary conditions shows Zenneck type behavior for the excited waves and are in excellent agreement with experimental results. In conclusion, we physically realize a radically different class of power transfer system, based on a wave, whose existence has been fiercely debated for over a century

Technologies of contraception and abortion

Soon to turn 60, the oral contraceptive pill still dominates histories of technology in the ‘sexual revolution’ and after. ‘The pill’ was revolutionary for many, though by no means all, women in the west, but there have always been alternatives, and looking globally yields a different picture. The condom, intrauterine device (IUD), surgical sterilization (male and female) and abortion were all transformed in the twentieth century, some more than once. Today, female sterilization (tubal ligation) and IUDs are the world's most commonly used technologies of contraception. The pill is in third place, followed closely by the condom. Long-acting hormonal injections are most frequently used in parts of Africa, male sterilization by vasectomy is unusually prevalent in Britain, and about one in five pregnancies worldwide ends in induced abortion. Though contraceptive use has generally increased in recent decades, the disparity between rich and poor countries is striking: the former tend to use condoms and pills, the latter sterilization and IUDs. Contraception, a term dating from the late nineteenth century and since then often conflated with abortion, has existed in many forms, and techniques have changed and proliferated over time. Diverse local cultures have embraced new technologies while maintaining older practices. Focusing on Britain and the United States, with excursions to India, China and France, this chapter shows how the patterns observed today were established and stabilized, often despite persistent criticism and reform efforts. By examining past innovation, and the distribution and use of a variety of tools and techniques, it reconsiders some widely held assumptions about what counts as revolutionary and for whom. Analytically, it takes up and reflects on one of the main issues raised by feminists and social historians: the agency of users as patients and consumers faced with choice and coercion. By examining practices of contraception alongside those of abortion, it revisits the knotty question of technology in the sexual revolution and the related themes of medical, legal, religious and political forms of control

Reconfigurable equalization for 10-Gb/sec serial data links in a 0.18-μm CMOS technology

The objective of the proposed research is to realize a 10-Gb/sec serial data link over band-limited channels, such as backplanes, multi-mode fiber, and copper-based cables that were originally designed for data rates less than 1Gb/sec. This is achieved using electrical equalization implemented in an integrated circuit (IC). To successfully compensate for various band-limited channels at the targeted data rate with a single equalizer IC, a reconfigurable equalizer topology is proposed. In order to realize the proposed goal, various channels are characterized of their forward transmission frequency response. Based on the measured channel data, system simulations are performed to identify the required specifications for IC implementation. This provides information such as optimal number of taps, fractionally-spaced tap delay, and tap coefficients for the proposed IC. With the obtained system requirements, IC building blocks are designed and fabricated in a 0.18- and #956;m CMOS technology. The fully-integrated reconfigurable CMOS equalizer provides a single-chip solution for compensating various band-limited channels. This enables 10-Gb/sec serial data transmission achieving signal integrity beyond their designed specifications