An improved calculation method of inductance and capacitances in π1 circuits for resonant power amplifiers

2012 ◽  
Vol 61 (2) ◽  
pp. 221-237
Author(s):  
Juliusz Modzelewski ◽  
Katarzyna Kulma
Keyword(s):  
Quality Factor ◽  
Power Amplifiers ◽  
Calculation Method ◽  
Load Resistance ◽  
Operating Frequency ◽  
Calculation Methods ◽  
Improved Method ◽  
Method Of Calculation ◽  
Class A ◽  
Input Parameters

An improved calculation method of inductance and capacitances in π1 circuits for resonant power amplifiers In the paper an improved method of calculation of the inductance and capacitances in the π1 circuit for Class A, AB, B, and C resonant power amplifiers is presented. This method is based on an assumption that the quality factor of the inductor is finite and the capacitors are lossless. The input parameters for calculations are the amplifier load resistance, the transistor load resistance, the quality factor of the inductor, the loaded quality factor of the designed circuit, and the operating frequency. The presented method allows reducing the required regulation range of π1 circuits elements in built resonant amplifiers as compared to the traditional calculation methods assuming lossless capacitors and inductor. This advantage is important, in particular, for long- and medium-wave transistor power amplifiers, where capacitances in π1 circuits are high comparing to typical trimming capacitors.

Comparative Analysis of the Effect of Loaded Quality Factor, Technology Node and Operating Frequency on Various Class E Power Amplifier Topologies

2020 ◽  
pp. 2150083
Author(s):  
Mir Mohsina Rahman ◽  
G. M. Rather
Keyword(s):  
Comparative Analysis ◽  
Quality Factor ◽  
Power Amplifier ◽  
Power Amplifiers ◽  
Operating Frequency ◽  
Resonant Circuit ◽  
Circuit Parameter ◽  
Power Added Efficiency ◽  
Technology Node ◽  
Class E

This paper aims to explore and compare the dependence of power amplifier performance parameters on the loaded quality factor of the resonant circuit, the technology node used and the operating frequency for different variants of the class E power amplifier. In spite of the fact that the circuit parameter variations of the basic class E amplifier are present in the literature, there is a lack of comparative analysis with respect to other class E power amplifiers based on diverse tuned load networks. Moreover, the effects of these three parameters are rarely discussed. The comparative analysis helps the designers to narrow down the selection of a power amplifier to be used for a particular application. This study is focused on the use of class E power amplifiers in biomedical implants at the Medical Implant Communication Service band and Industrial Scientific and Medical band. It is observed that the power added efficiency and the power gain have an inverse dependence on the loaded quality factor, frequency and the technology node while the output power depends directly on these parameters.

scholarly journals Methodological Foundations of Mathematical Modeling of the Basic System of Indicators of Information Integrated Logistic Support of Exported Knowledge-Intensive Products

2021 ◽  
Vol 7 (1) ◽  
pp. 32-38
Author(s):  
S.V. Veretekhina ◽  
◽  
Keyword(s):  
International Market ◽  
High Tech ◽  
Basic System ◽  
Calculation Methods ◽  
Method Of Calculation ◽  
Independent Variables ◽  
Knowledge Intensive ◽  
Logistic Support ◽  
Integrated Logistics ◽  
Markov Method

the article describes a general approach for the formation of a basic system of integrated logistics support indicators based on the example of the export of high-tech products. A review of domestic standards for the calculation of various indicators is carried out. The applied calculation methods are described, the choice of the Markov method of calculation is justified, and the search for independent variables and constants is carried out. In conclusion, the conclusions about the need to develop a set of measures to support exports are presented. It is proved that the use of integrated logistics support provides an increase in the competitiveness of domestic knowledge-intensive products on the international market.

Performance Evaluation of Japanese Nuclear Power Plant Based on Open Data and Information (3)

2010 ◽  
Author(s):  
Tadahisa Nagata ◽  
Ken-ichiro Sugiyama
Keyword(s):  
Renewal Process ◽  
Calculation Method ◽  
Nuclear Power ◽  
Power Plants ◽  
Failure Modes ◽  
Continuous Data ◽  
Weibull Analysis ◽  
Improved Method ◽  
Early Failure ◽  
Restoration Process

The excessive maintenance of the nuclear power plants (NPPs) may cause the early (infant) failure in Japan. An easy analysis; the Weibull analysis was applied to the evaluation of the failure mode. The Weibull analysis needs the hazard data. The maintenance information of the equipment which caused plant shutdown was required for the hazard calculation. However, maintenance information of the equipment was not open. Therefore, all equipment was assumed to be maintained during every shutdown. This assumption was based on renewal process. However, a repair after unplanned shutdown of NPP is generally a restoration of only failed function without system overhaul. The system must be considered to age continuously. The system was not renewed. The operation data must be regarded as one continuous data before and after unplanned shutdown. An improvement of the Weibull analysis was required for NPPs. The model of the Weibull analysis was investigated. The competitive model in which shutdown caused by other than focused equipment/cause may be supposed to be continuous data could not be applied for a comprehensive analysis. Furthermore, the calculation method of the Weibull analysis was investigated. The calculation method of the hazard was viewed. A denominator of the hazard is the number of data which is cut for every continuous data by renewal process. However, multiple considerations of operation periods before unplanned shutdowns might cause underestimation of the failure rate in case of restoration process. Therefore, a dominator of the hazard was not supposed to be the number of data but the number of survived equipments (plants) at each time according to the definition of the hazard. This improved method is for the restoration process. The performance of Japanese NPPs was evaluated by improved method. The failure modes of Japanese NPPs were early failure modes. Moreover, performances of U.S. NPPs was tried to be evaluated by improved method. Operation data was collected from “NRC Power Reactor Status Reports”. However, many “maintenance outage”s which are the shutdowns of unknown origin were found. Therefore, DOE information was supplemented to investigate the “maintenance outage”. Failure modes of U.S. NPPs were the early failure modes, and failure rates were larger than Japanese NPPs.

METHOD OF CALCULATION THE STABILITY OF AN EXCAVATOR EQUIPPED WITH A CONE ROLLER

2021 ◽  
pp. 12-16
Author(s):  
K. Z. Tilloev ◽  
S. V. Kondakov
Keyword(s):  
Mechanical Properties ◽  
Calculation Method ◽  
Physical And Mechanical Properties ◽  
Maximum Force ◽  
Compacted Soil ◽  
Method Of Calculation ◽  
Support Roller ◽  
The Stability

The construction and method of calculating the stability of a crawler excavator equipped with a new working body (cone roller) are considered. The calculation is made on two working positions (longitudinal and transverse) of the excavator, provided that the excavator must apply the maximum force on the working body at an angle of 90°. The force applied by the excavator boom to the cone roller during the introduction depends on the physical and mechanical properties of the compacted soil. The calculation method differs in that during the compaction of the roadbed, the cone sinks into the ground, and the excavator tends to roll in the direction of the rear track support roller, in contrast to the traditional danger of tipping over the front support roller when working with a bucket.

Crack width calculation methods for large-scale concrete structures for the Ferry-Free E39

2018 ◽  
Author(s):  
Reignard Tan ◽  
Terje Kanstad ◽  
Mette R. Geiker ◽  
Max A. N. Hendriks
Keyword(s):  
Cross Sections ◽  
Calculation Method ◽  
Crack Width ◽  
Large Scale ◽  
Concrete Structures ◽  
Calculation Methods ◽  
Empirical Formulas ◽  
Eurocode 2 ◽  
Semi Empirical

<p>Motivated by the establishment of a Ferry-Free E39 coastal highway route, crack width calculation methods for design of large-scale concrete structures are discussed. It is argued that the current semi-empirical formulas recommended by Eurocode 2 is inconsistent and overly conservative for cross sections with large bar diameters and covers. A suggestion to formulating a more consistent crack width calculation method is given.</p>

Solving Decommissioning and Abandonment Problems When Planning to Shear 9 5/8-inch Casing in a 13 5/8-inch × 10k RAM BOP

2021 ◽  
Author(s):  
David Earl Cain ◽  
Keith Albert Klopfenstein ◽  
James Robert McMullan
Keyword(s):  
Calculation Method ◽  
Shear Force ◽  
Statistical Treatment ◽  
The Novel ◽  
Test Results ◽  
Calculation Methods ◽  
Working Pressure ◽  
Lower Shear ◽  
Validation Testing ◽  
Force Pressure

Abstract A decommissioning and abandonment requirement to shear 9 5/8-inch casing in certain circumstances with a 13 5/8-inch × 10,000 psi rated working pressure, RWP, Shear RAM type blowout preventer, BOP, resulted in a need to develop a novel casing shear device and shear calculation method. Results of shear testing, future engineering planning guidance, the new shear calculation method, and comparison to legacy technology are included in this paper. Interaction with the end user to understand requirements, a five-step problem solving procedure, a basis of design process, materials justification, verification analysis, validation testing, and describing an improved shear operator force/pressure calculation are all described. Shear larger casing in the required and restrictive RAM BOP and well bore presented a problematic challenge. Equally, tubular fish size was required to support fishing extraction operations following shear. Validation test results exceeded requirements and resulted in the need for a new approach to the shear calculation method. The novel shear RAM geometry was developed utilizing shear calculation methods which were based on legacy considerations. API 16A shear validation procedures and two legacy shear calculation methods where employed. Shear calculations are used to anticipate the RAM BOP operator pressures required to shear a specific tubular. The larger than historically allowed casing size to be sheared in a 13 5/8-inch × 10,000 psi RAM BOP meant higher operator pressures were anticipated for each operator option. A Novel shear RAM geometry was developed as a design intent to lower shear force/pressure. There was an observation during validation testing that the geometry exceeded expectations to lower shear pressure significantly. This observation led to a conclusion that an improved shear calculation method was required for this application. This novel calculation method description / statistical treatment, test results, RAM design methods, and tabular shear engineering planning information are included in this paper. One additional requirement of the shear RAM geometry was to provide an upper and lower fish deformed surface which could be easily retrieved thru the 13 5/8-inch BOP bore. An additional observation was that the fish width requirement was achieved. The novel shear calculation method allows an engineer to precisely plan for bonnet actuation pressures when larger casing is sheared. The precise calculation of shear force/pressure also assists with BOP operator size and type selection. The engineer will gain casing size versus shear pressure for specific operator options in tabular format. Planners will gain insight into tubular fish deformation estimation allowing mitigation of tubular extraction risk during operations planning.

scholarly journals Reply to Nicholson's comment on "Consistent calculation of aquatic gross production from oxygen triple isotope measurements" by Kaiser (2011)

2012 ◽  
Vol 9 (8) ◽  
pp. 2921-2933 ◽  
Author(s):  
J. Kaiser ◽  
O. Abe
Keyword(s):  
Isotope Fractionation ◽  
Direct Calculation ◽  
Original Data ◽  
Delta Method ◽  
Base Case ◽  
Calculation Methods ◽  
Input Parameters ◽  
Net To Gross ◽  
Number Of Publications ◽  
Definition Of

Abstract. The comment by Nicholson (2011a) questions the "consistency" of the "definition" of the "biological end-member" used by Kaiser (2011a) in the calculation of oxygen gross production. "Biological end-member" refers to the relative oxygen isotope ratio difference between photosynthetic oxygen and Air-O2 (abbreviated 17δP and 18δP for 17O/16O and 18O/16O, respectively). The comment claims that this leads to an overestimate of the discrepancy between previous studies and that the resulting gross production rates are "30% too high". Nicholson recognises the improved accuracy of Kaiser's direct calculation ("dual-delta") method compared to previous approximate approaches based on 17O excess (17Δ) and its simplicity compared to previous iterative calculation methods. Although he correctly points out that differences in the normalised gross production rate (g) are largely due to different input parameters used in Kaiser's "base case" and previous studies, he does not acknowledge Kaiser's observation that iterative and dual-delta calculation methods give exactly the same g for the same input parameters (disregarding kinetic isotope fractionation during air-sea exchange). The comment is based on misunderstandings with respect to the "base case" 17δP and 18δP values. Since direct measurements of 17δP and 18δPdo not exist or have been lost, Kaiser constructed the "base case" in a way that was consistent and compatible with literature data. Nicholson showed that an alternative reconstruction of 17δP gives g values closer to previous studies. However, unlike Nicholson, we refrain from interpreting either reconstruction as a benchmark for the accuracy of g. A number of publications over the last 12 months have tried to establish which of these two reconstructions is more accurate. Nicholson draws on recently revised measurements of the relative 17O/16O difference between VSMOW and Air-O2 (17δVSMOW; Barkan and Luz, 2011), together with new measurements of photosynthetic isotope fractionation, to support his comment. However, our own measurements disagree with these revised 17δVSMOW values. If scaled for differences in 18δVSMOW, they are actually in good agreement with the original data (Barkan and Luz, 2005) and support Kaiser's "base case" g values. The statement that Kaiser's g values are "30% too high" can therefore not be accepted, pending future work to reconcile different 17δVSMOW measurements. Nicholson also suggests that approximated calculations of gross production should be performed with a triple isotope excess defined as 17Δ#≡ ln (1+17δ)–λ ln(1+18δ), with λ = θR = ln(1+17&amp;varepsilon;R ) / ln(1+18&amp;varepsilon;R). However, this only improves the approximation for certain 17δP and 18δP values, for certain net to gross production ratios (f) and for certain ratios of gross production to gross Air-O2 invasion (g). In other cases, the approximated calculation based on 17Δ† ≡17δ – κ 18δ with κ = γR = 17&amp;varepsilon;R/18&amp;varepsilon;R (Kaiser, 2011a) gives more accurate results.

Sign in / Sign up

Export Citation Format

Share Document