Resonant body transistors in standard CMOS technology

This work presents Si-based electromechanical resonators fabricated at the transistor level of a standard SOI CMOS technology and realized without the need for any postprocessing or packaging. These so-called Resonant Body Transistors (RBTs) are driven capacitively and sensed by piezoresistively modulating the drain current of a Field Effect Transistor (FET). First generation devices operating at 11.1-11.5 GHz with footprints of 3μm×5μm are demonstrated. These unreleased bulk acoustic resonators are completely buried within the CMOS stack and acoustic energy at resonance is confined using Acoustic Bragg Reflectors (ABRs). The complimentary TCE of Si/SiO[subscript 2] in the resonator and the surrounding ABRs results in a temperature stability TCF of <;3 ppm/K. Comparative behavior of devices is also discussed to analyze the effect of fabrication variations and active sensing.United States. National Security Agency. Trusted Access Program OfficeUnited States. Defense Advanced Research Projects Agency. Leading Edge Access ProgramIBM Researc

Resonant Body Transistors in IBM's 32nm SOI CMOS technology

This work presents an unreleased CMOS-integrated MEMS resonators fabricated at the transistor level of IBM's 32SOI technology and realized without the need for any post-processing or packaging. These Resonant Body Transistors (RBTs) are driven capacitively and sensed piezoresistively using an n-channel Field Effect Transistor (nFET). Acoustic Bragg Reflectors (ABRs) are used to localize acoustic vibrations in these resonators completely buried in the CMOS stack and surrounded by low-k dielectric. Experimental results from the first generation hybrid CMOS-MEMS show RBTs operating at 11.1-11.5 GHz with footprints <; 5μm × 3μm. The response of active resonators is shown to contrast with passive resonators showing no discernible peak. Comparative behavior of devices with design variations is used to demonstrate the effect of ABRs on spurious mode suppression. Temperature stability and TCF compensation due to complimentary materials in the CMOS stack are experimentally verified

Blue carbon ecosystem monitoring using remote sensing reveals wetland restoration pathways

In an era of climate and biodiversity crises, ecosystem rehabilitation is critical to the ongoing wellbeing of humans and the environment. Coastal ecosystem rehabilitation is particularly important, as these ecosystems sequester large quantities of carbon (known in marine ecosystems as “blue carbon”) thereby mitigating climate change effects while also providing ecosystem services and biodiversity benefits. The recent formal accreditation of blue carbon services is producing a proliferation of rehabilitation projects, which must be monitored and quantified over time and space to assess on-ground outcomes. Consequently, remote sensing techniques such as drone surveys, and machine learning techniques such as image classification, are increasingly being employed to monitor wetlands. However, few projects, if any, have tracked blue carbon restoration across temporal and spatial scales at an accuracy that could be used to adequately map species establishment with low-cost methods. This study presents an open-source, user-friendly workflow, using object-based image classification and a random forest classifier in Google Earth Engine, to accurately classify 4 years of multispectral and photogrammetrically derived digital elevation model drone data at a saltmarsh rehabilitation site on the east coast of Australia (Hunter River estuary, NSW). High classification accuracies were achieved, with >90% accuracy at 0.1 m resolution. At the study site, saltmarsh colonised most suitable areas, increasing by 142% and resulting in 56 tonnes of carbon sequestered, within a 4-year period, providing insight into blue carbon regeneration trajectories. Saltmarsh growth patterns were species-specific, influenced by species’ reproductive and dispersal strategies. Our findings suggested that biotic factors and interactions were important in influencing species’ distributions and succession trajectories. This work can help improve the efficiency and effectiveness of restoration planning and monitoring at coastal wetlands and similar ecosystems worldwide, with the potential to apply this approach to other types of remote sensing imagery and to calculate other rehabilitation co-benefits. Importantly, the method can be used to calculate blue carbon habitat creation following tidal restoration of coastal wetlands

Distributed defense scheme for managing DNS reflection attack in network communication systems

Domain Name System (DNS) is based on client-server architecture and employed User Packet Diagram (UDP) protocol to transport requests and responses. Due to UDP supports unreliable connection, malicious users are able to fabricate spoofed DNS requests very easily. Such DNS problems in turn affect numerous other network services and critical in resource utilization. Delay in deploying secure DNS motivates the need for local networks to protect DNS infrastructure. DNS reflection attack for example takes advantage of the DNS response message and results substantially larger than DNS query messages. In this work, we propose a distributed defense scheme in DNS infrastructure to prevent from reflection attack. Our defense scheme aims to prevent spoofed addresses from getting any responses by applying a classification-based packet filtering strategy. Specifically, our local DNS server regularly checked DNS requests in its database in order to differentiate between legitimate and illegitimate requests. We invent validation phase in our filtering strategy by getting confirmation before the request stored in local side server. The key idea behind this is to ensure the local DNS database is merely stored legitimate requests and prevent the fake DNS request transferred to users. Our analysis and the corresponding experimental results show that the proposed scheme offers an effective defense solution while implicitly improving network communication traffic

Detection of early antiangiogenic effects in human colon adenocarcinoma xenografts: in vivo changes of tumor blood volume in response to experimental VEGFR tyrosine kinase inhibitor

Antiangiogenesis is emerging as efficient strategy for targeting and potentially eliminating neoplastic tumor vessels. The main goal of this study was to establish whether absolute tumor blood volume (V(b)) change could be used as an early predictor of antiangiogenesis in ectopic and orthotopic colon carcinomas. To assess therapy-induced changes of V(b), we did comparative analysis of signal intensities in tumors and muscle using steady-state magnetic resonance imaging (MRI) assisted with an intravascular paramagnetic contrast agent [gadolinium-labeled protected graft copolymer (PGC-Gd)]. Athymic mice with implanted human MV522 tumors were treated with vascular endothelial growth factor type 2 receptor tyrosine kinase inhibitor (VEGFR2-TKI) that has been shown to inhibit VEGFR2 phosphorylation and tumor growth in vivo. Animals were imaged either after a single day or after a 1-week course of treatments. The measured V(b) in ectopic tumors was 2.5 +/- 1.5% of total tissue volume 1 week after the implantation (n = 8). Two doses of VEGFR2-TKI (25 mg/kg, p.o., b.i.d.) resulted in a decrease of V(b) to 1.3 +/- 0.3%. In orthotopic tumors, the measured V(b) was initially higher (11.9 +/- 2.0%); however, VEGFR2-TKI treatment also resulted in a statistically significant decrease of V(b). The absolute V(b) was not affected in the muscle as a result of treatments. MRI measurements were corroborated by using isotope and correlative histology experiments. Our results show that steady-state MRI is highly sensitive to early antiangiogenic effects caused by small molecule drugs

The Impact of Teaching Materials on Learning Computer Programming Languages in Kurdistan Region Universities and Institutes

It is evident that learning and teaching computer programming are considered as one of the striking challenges in academic environments. Meanwhile, selecting the correct and appropriate materials can leave an enormous impact in learning computer programming languages. However, recently this argument has been put under scrutiny as to which types of materials motivate learners to learn computer programming languages as well as enhance learning outcomes. Therefore, the main objective of this study is to investigate the current teaching and learning materials of computer programming languages in Kurdistan region of Iraq universities. Additionally, another aim is to give a rigorous analysis of how materials help students to learn computer programming language. A further focus is to identify the difficulties of learning computer programming languages at undergraduate level which constitutes technical Diploma and Bachelor. The last but not the least, this paper examines new approaches to teaching programming languages as a cognitive model for programming education

Prioritization of Factors Affecting Time Management among Health Managers

Introduction: In today's world, having principle and targeted management is one of the progress and development factors of any organization. Effective use of time for each manager is the most important base for managing current affairs and controlling daily activities. The present study aimed to investigate and analyze the relationship between factors affecting time management among the senior, middle and first-line managers of the hospitals in Kermanshah in 2015. Methods: This was a cross-sectional and descriptive-analytical study conducted in 2015 in ten hospitals of Kermanshah. The study population consisted of all senior, middle and first-line managers of the studied hospitals (N=240) which were selected using census method. The required data were collected using a researcher-made pair-wise comparison questionnaire. The collected data were analyzed using the DEMATEL technique through Matlab8.1.0.604 software. Results: The results showed that, from the studied managers’ viewpoints, the variables of goal setting and prioritization of objectives and activities were certainly affecting variables and located in the cause group. Also, the variables of planning, delegation, communication management, and meetings management were affected variables and located in the effect group. Furthermore, in the hierarchy of affecting and affected variables influencing time management, goal setting and meetings management with the coordinates (1.23, 1.23) and (1.06, -1.05) were identified as the highest and lowest priorities and were considered as the most affecting and most affected variables, respectively. Conclusion: The results of the present study showed that among the studied variables influencing time management, goal setting was the highest priority and most affecting variable, and meetings management was the lowest priority and the most affected variable. It is recommended to increase the hospital managers’ knowledge about time management and the need for accurate goal setting through providing management and time management courses, and requiring them to develop a time management plan in order to improve their time management

On the Numerical Solution for Two Dimensional Laplace Equation with Initial Boundary Conditions by using Finite Difference Methods

In this study, Laplace partial differential equations with initial boundary conditions has been studied. A numerical method has been proposed for the solution of the IBVP Laplace equation. The technique based on finite difference methods. The stability of the difference schemes are guaranteed. Approximation solution of the problem was achieved. For testing the accuracy of the proposed method, two different initial boundary value problems are provided. Moreover, a comparison between the numerical solution and analytical solution has been done. MATLAB software implemented for calculation of absolute errors. Illustration graphs presented. It has been demonstrated that the results of the comparison guarantee the accuracy and reliability of the provided method

Numerical Solution for Time Period of Simple Pendulum Under Magnetic Field

In the present study, the numerical solution of the time period of a Simple Pendulum under a magnetic field investigated. The analytical solution presented for the given problem. The numerical solution for the problem achieved by using two numerical quadrature methods, namely, Simpson’s 3/8 and Boole’s method. The period of a simple pendulum with a large angle is presented. The results of the numerical quadrature have been compared to the exact solution. Absolute and relative mistakes of the problem have been presented. The Matlab program 2013R has created a numerical method to analyze the outcome. Moreover, it is established that the comparison results guarantee the present method's ability and accuracy