The relationship between impedance matching and gain sensitivity to the active component variations in a low-pass negative resistance amplifier

1967 ◽  
Vol 55 (5) ◽  
pp. 709-709 ◽  
Author(s):  
G. Martinelli ◽  
A. Roveri
Keyword(s):  
Active Component ◽  
Impedance Matching ◽  
Negative Resistance ◽  
Low Pass ◽  
The Relationship

Selectivity and in-band impedance enhancement of a compact slot antenna with defected ground structures

2019 ◽  
Vol 11 (10) ◽  
pp. 1010-1016
Author(s):  
Hailong Yang ◽  
Xiaoli Xi ◽  
Lili Wang ◽  
Yuchen Zhao ◽  
Xiaomin Shi
Keyword(s):  
Reflection Coefficient ◽  
Impedance Matching ◽  
Ultra Wideband ◽  
Band Edge ◽  
Slot Antenna ◽  
Defected Ground Structure ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Uwb Antennas ◽  
Low Pass

AbstractIn this study, a new ultra-wideband (UWB) band-edge selectivity antenna with a modified radiation slot using defected ground structure (DGS) is presented to obtain bandpass filtering reflection coefficient and gain performance. The well-designed DGS is designed on backside metallic of the substrate and can be seen as a low-pass filter that provides a good roll-off at a higher frequency. By connecting the DGS and the stepped slot and making them merge with each other, good cut-off property in the upper passband and better in-band impedance characteristics are obtained. Measured results show that the proposed design not only shows good band-edge selectivity in reflection coefficient and gain performance but also has a good impedance matching of −13.5 dB reflection coefficients and a good radiation efficiency of 90% in the operating frequencies. The measured bandwidth defined with the reflection coefficient less than −10 dB is from 3.1–11.2 GHz. Furthermore, the size of the filtering UWB antenna is 22 mm × 12 mm, which is smaller than many individual UWB antennas and UWB filters.

scholarly journals Redesigning a “Writing for Chemists” Course Using Specifications Grading

2020 ◽  
Author(s):  
Stephen Mang ◽  
Kate J. McKnelly ◽  
Michael Morris
Keyword(s):  
Student Learning ◽  
Learning Outcomes ◽  
Student Learning Outcomes ◽  
Graduation Requirement ◽  
School Year ◽  
Low Pass ◽  
The University ◽  
The Relationship ◽  
Writing Practice ◽  
High Pass

The Department of Chemistry at the University of California, Irvine (UCI) instituted an upper-division “Writing for Chemists” course in fall 2017 that fulfills part of UCI’s writing graduation requirement. During the 2019-2020 school year, we re-designed the course using a specifications grading system with the following goals: 1) to teach students how to develop their own writing practice, while mastering chemistry discipline-specific writing conventions, 2) to provide students with frequent and constructive instructor and teaching assistant (TA) feedback by providing ample revision opportunities, 3) to increase transparency in how students can achieve course SLOs, and 4) to provide students with consistent and clear assessment rubrics. This specifications grading approach uses a high-pass, low-pass, unsatisfactory system predicated on whether students meet a certain number of criteria for each assignment. Achievement of Student Learning Outcomes (SLOs) was assessed using criteria instead of points so that instructors and students could more objectively measure student learning. Standardized rubrics and a student grade tracker helped students understand the relationship between meeting criteria, achieving SLOs, and earning grades. Students completed surveys at the end of the course to determine if their writing habits and attitudes towards writing changed. After the course, students self-reported increased propensities to pre-write and edit, and several students mentioned that they appreciated the transparency of the specifications rubrics and the control the specifications system gave them over their grades.

scholarly journals Simultaneous Design of Low-Pass Filter with Impedance Matching Transformer for SONAR Transducer Using Particle Swarm Optimization

Energies ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4646
Author(s):  
Jae-Hyuk Choi ◽  
Hyung-Soo Mok
Keyword(s):  
Particle Swarm Optimization ◽  
Impedance Matching ◽  
Particle Swarm ◽  
Acoustic Signals ◽  
Design Methods ◽  
Swarm Optimization ◽  
Pass Filter ◽  
Low Pass Filter ◽  
Simultaneous Design ◽  
Low Pass

Sound navigation and ranging (SONAR) systems detect a target in the front direction by using acoustic signals. A switching-type power conversion system is used to improve power efficiency, and an impedance matching circuit is used to decrease reactive power. A low-pass filter is used to improve the quality of acoustic signals. To achieve the desired voltage level for a SONAR transducer, a transformer is connected in series with a low-pass filter. In conventional design methods, design value errors occur because the components are designed independently and later combined. Moreover, if parameters that considerably impact operating characteristics are ignored in the design process, these errors will increase. Hence, time and cost losses are incurred during refabrication because operational characteristics differ from design values. To solve this problem, this study proposes the simultaneous design of a low-pass filter and impedance matching circuit, which includes critical design parameters, utilizing the particle swarm optimization algorithm. Moreover, conventional design methods were examined, and the superiority of the proposed design method to conventional methods was verified through analyses and experiments in terms of overall impedance phase and filter blocking characteristics.

scholarly journals Eddy Trains and Striations in Quasigeostrophic Simulations and the Ocean

2016 ◽  
Vol 46 (9) ◽  
pp. 2807-2825 ◽  
Author(s):  
Changheng Chen ◽  
Igor Kamenkovich ◽  
Pavel Berloff
Keyword(s):  
North Pacific ◽  
Empirical Orthogonal Functions ◽  
Eof Analysis ◽  
Sea Level Anomaly ◽  
Orthogonal Functions ◽  
The North ◽  
Temporal Averaging ◽  
Low Pass ◽  
The Relationship ◽  
The North Pacific

AbstractThis study explores the relationship between coherent eddies and zonally elongated striations. The investigation involves an analysis of two baroclinic quasigeostrophic models of a zonal and double-gyre flow and a set of altimetry sea level anomaly data in the North Pacific. Striations are defined by either spatiotemporal filtering or empirical orthogonal functions (EOFs), with both approaches leading to consistent results. Coherent eddies, identified here by the modified Okubo–Weiss parameter, tend to propagate along well-defined paths, thus forming “eddy trains” that coincide with striations. The striations and eddy trains tend to drift away from the intergyre boundary at the same speed in both the model and observations. The EOF analysis further confirms that these striations in model simulations and altimetry are not an artifact of temporal averaging of random, spatially uncorrelated vortices. This study suggests instead that eddies organize into eddy trains, which manifest themselves as striations in low-pass filtered data and EOF modes.

The Development of Photocatalytic Systems Entitled Titanium Dioxide Nanoparticles Attached to Polypropylene Fibrous Carrier for Freshwater Disinfection

2014 ◽  
Vol 1040 ◽  
pp. 183-187 ◽  
Author(s):  
Ilia A. Lysak ◽  
Galina V. Lysak ◽  
Tatyana D. Malinovskaya ◽  
Anatoly S. Ruhov
Keyword(s):  
Titanium Dioxide ◽  
Active Component ◽  
Microbial Contamination ◽  
High Efficiency ◽  
Titanium Dioxide Nanoparticles ◽  
Antibacterial Treatment ◽  
Bactericidal Properties ◽  
Current Article ◽  
Composition Structure ◽  
The Relationship

In the current article the use of nanoparticles of titanium dioxide is justified to be an active component of the photocatalytic materials. The relationship between composition, structure and bactericidal properties of titanium dioxide is also established. It is shown that the polypropylene carrier comprising on a surface of at least 2.1 ± 0.3 mg/g of titanium dioxide nanoparticles, where both phases of titanium dioxide such as rutile and anatase are presented, allows the antibacterial treatment of water with high efficiency and it can be used for water purification from microbial contamination.

Low-pass impedance matching filters for packaged low-cost laser diodes

2003 ◽  
Vol 37 (3) ◽  
pp. 194-196 ◽  
Author(s):  
H. Music ◽  
A. Alping ◽  
U. Johansson ◽  
T. Hedquist ◽  
Spartak Gevorgian
Keyword(s):  
Low Cost ◽  
Impedance Matching ◽  
Laser Diodes ◽  
Low Pass
Sign in / Sign up

Export Citation Format

Share Document