Efficient Formula Research Articles

Numerical study of transmissive liquid crystal Pancharatnam–Berry gratings with small periods

Advances in patterning molecular orientations in liquid crystals have made possible the fabrications of various high-quality flat optical elements, ranging from gratings to beam shaping devices. These devices are based on modulating the Pancharatnam–Berry (PB) phase. It is well known that the diffraction efficiency for liquid crystal PB optical elements decreases for large diffraction angles. Here we study this issue using numerical simulations based on finite-difference time-domain algorithms and show that the optical efficiency formula commonly used for liquid crystal gratings deviates significantly from numerical results and is inaccurate for small grating periods because of its assumption that light beams do not diffract inside the liquid crystal films. We show that, for large diffraction angles, the polarization of the diffracted beam is generally elliptically polarized, and we further show that, by using liquid crystal materials with larger birefringence Δ n ∼ 0.4 , the diffraction efficiency for a grating period of 0.8 µm can go above 90%, which can be used for various flat optical elements with numerical aperture ∼ 0.7 .

EFEK PENGGUNAAN DOUBLE DAN SINGLE PISTON CALIPER TERHADAP WAKTU DAN JARAK TEMPUH PADA PENGEREMAN SEPEDA MOTOR 125 CC

This study aims to determine the distance and braking time on 125cc motorcycle vehicles by using two types of callipers, namely single-piston and double-piston callipers. The research method uses experimental methods. There this method will compare 2 variables to get the results of the study by sulking on SNI Braking. By varying the two callipers of different types and using the brake pressure gauge, stopwatch, and meter to find out the pressure, time, and distance when conducting the test, the results of the test are calculated by the formula of regularly changing straight motion force (GLBB) slowed down, braking force and braking efficiency formula in order to get more valid results. Based on the results of this research report, it was concluded that the 2-piston callipers are superior to the 1-piston callipers in terms of average mileage of 0.51 m (9.81 m – 9.30 m) in front wheel braking and average mileage of 0.42 m (4.63 m – 4.21 m) in rear wheel braking and average stopping time of 0.21 s (2.51 s – 2.30 s) with the average effect of braking efficiency value of 5% (57% - 52 %) on front wheel braking and the average time for 0.21 s (1.58 s – 1.37 s) with the average effect of efficiency value of 5 % (47 % - 42 %) on rear wheel braking. So that makes 2-piston callipers better used in 125 cc vehicles than 1-piston callipers in terms of braking aspects.

Estimation of an empirical formula for efficiency of a BEGe type detector using machine learning based algorithm

The objective of this study is to establish an empirical formula of full-energy peak efficiency (FEPE), for a Broad Energy High Purity Germanium (BEGe) type detector. FLUKA Monte Carlo-based code is used in this work to simulate radiation transport in the BEGe detector, and FEPE values have been estimated for various gamma energies and wide range of commercially available detector configurations. Then, using machine learning-based non-linear regression models, an empirical formula relating FEPE values with detector configuration (active volume and diameter-to-length ratio) and incident gamma radiation (energy >122 keV) is obtained. The results show that the effect of diameter-to-length ratio on FEPE values cannot be ignored in the case of a BEGe detector, which is not observed in case of coaxial type detectors. At lower energies, the efficiency of the BEGe detector is higher than the coaxial detector due to its large diameter-to-length ratio. This empirical formula can be used to quickly estimate FEPE values and verify nominal geometric parameters provided by the manufacturer.

Multiple mitochondria-targeted components screened from Sini decoction improved cardiac energetics and mitochondrial dysfunction to attenuate doxorubicin-induced cardiomyopathy.

Rationale: Sini decoction (SND) is an efficient formula against DOX-induced cardiomyopathy (DCM), but the active ingredient combination (AIC) and mechanisms of SND remain unclear. Therefore, the present study aimed to identify the AIC and elucidate the underlying mechanism of AIC on DCM. Methods: The AIC were screened by a novel comprehensive two-dimensional cardiac mitochondrial membrane chromatography (CMMC)-TOFMS analysis system and further validated by cell viability, reactive oxygen species (ROS) generation, ATP level, and mitochondrial membrane potential in DOX-induced H9c2 cell injury model. Then, an integrated model of cardiac mitochondrial metabolomics and proteomics were applied to clarify the underlying mechanism in vitro. Results: The CMMC column lifespan was significantly improved to more than 10 days. Songorine (S), neoline, talatizamine, 8-gingerol (G) and isoliquiritigenin (I), exhibiting stronger retention on the first-dimension CMMC column, were screened to have protective effects against DOX cardiotoxicity in the H9c2 cell model. S, G and I were selected as an AIC from SND according to the bioactivity evaluation and the compatibility theory of SND. The combined in vitro use of S, G and I produced more profound therapeutic effects than any component used individually on increasing ATP levels and mitochondrial membrane potential and suppressing intracellular ROS production. Moreover, SGI attenuated DCM might via regulating mitochondrial energy metabolism and mitochondrial dysfunction. Conclusions: The provided scientific evidence to support that SGI combination from SND could be used as a prebiotic agent for DCM. Importantly, the proposed two-dimensional CMMC-TOFMS analytical system provides a high-throughput screening strategy for mitochondria-targeted compounds from natural products, which could be applied to other subcellular organelle models for drug discovery.

RESOURCEFUL APPROACH TO THE ASSESSMENT OF PRODUCTION PERFORMANCE

The present paper suggests methods of resourceful approach to designing of the index of total remunerative production performance. The cost of all resources used in production object is presented in tangible and intangible forms - human capital. Probable capital costs of human resources and virtual costs of indirect state-owned resources are measured by indirect methods, i.e. by designing the system of probable index equivalent to the market paragon. The authors present the examples of calculations for performance criteria of commercial regional production performance. This cost is calculated by the amount of income paid by the resident manufacturer to the direct participants in the production: entrepreneurs, employees and the indirect participant - the state. Based on the sum of the equity results, the consolidated self-calculated result of production is determined, as well as its factor value, created from the use of capital of real and human capital. Ultimately, the formula of self-calculated regional production efficiency was proposed and tested. The problem of using the same terminology at different levels of management to denote different phenomena in essence has also been identified. With this in mind, to enhance the validity and information of assessment, the measures for methods of accounting, taxation and statistics upgrading are also suggested.

Hydrodynamic Decomposition-Based Optimization of Ship’s Hull–Propeller System Under Multiple Operating Conditions

_ In this research, a framework for the analysis and design optimization of ship hull–propeller systems (HPSs) in waves is developed. This framework can be utilized as an efficient synthesis tool to determine the main geometric characteristics of the HPSs during the early stage of ship design. The optimization is carried out in two levels and under multipoint operating conditions (OC). Multiobjective evolutionary algorithm based on decomposition (MOEA/D) as an efficient multiobjective evolutionary algorithm, Michell integral and OpenProp tool as low-fidelity hydrodynamic solvers and boundary element method (BEM) as medium-fidelity solver are applied on two case studies to minimize the effective power and maximize the propulsive efficiency of HPSs. To estimate the added wave resistance, an efficient semiempirical formula is also employed. The Series 60 hull form with DTMB P4118 single propeller and S175 hull form with KP505 twin-propeller are considered as the original models. The numerical results show that the framework can find optimized designs with better hydrodynamic performance. Introduction Optimizing the hydrodynamic performance of ships’ hull and propeller(s) based on multiple design condition has gained considerable importance over the last few years. High fuel oil costs are the reason that shipyards and ship owners are now focusing more than ever on the reduction of effective power and propulsive efficiency. Hydrodynamic performance parameters, such as effective power and propulsive efficiency, are determined by the hull form and propeller shape, so it is very important to choose a hull–propeller system (HPS) with good performance in early stage ship design. There exist two main factors in the hydrodynamic design optimization of marine systems. The first factor is simultaneously considering all components of the system influencing objective function(s) and the second one is selecting a less time-consuming solver with satisfactory accuracy. In the ship design process, these two factors must be taken for conducting a reasonable optimization into consideration.

Efficient analytical method for computing the acoustic field inside enclosures with a mixed rectangular-cylindrical geometry

Enclosures with a mixed rectangular-cylindrical geometry are common in sacred, historic and modern buildings. Therefore, obtaining efficient analytical formulas for describing the sound radiation inside such structures is of practical importance. These formulas can be implemented in open-source software and can aid in the analysis of acoustic fields. In this study, the problem of sound radiation by a point source located inside a rectangular enclosure with a sound-absorbing quarter-cylindrical ceiling was analytically solved. The formulas presented in this paper can also be used to obtain the eigenfrequencies and eigenfunctions. To obtain the analytical solution, two connected subregions, namely rectangular space, and quarter-cylinder, were considered, and the continuity conditions were imposed on the region’s coupling interface. The acoustic field was described using the solution for a rigid-walled room and the additional components containing the Fourier and Dini series. These components allow the solution to satisfy the impedance boundary condition and the continuity conditions. The formulas and their computer implementation were validated using the finite element method (FEM). A good agreement was achieved between results given by both methods. The numerical analysis demonstrated that the use of the formulas is less time-consuming than using FEM when the frequency is greater than 150 Hz. Moreover, compared to FEM, the analytical solution can be applied to higher frequencies for which the use of FEM requires hardware with high computing capability.

Hepp’s bound for Feynman graphs and matroids

We study a rational matroid invariant, obtained as the tropicalization of the Feynman period integral. It equals the volume of the polar of the matroid polytope and we give efficient formulas for its computation. This invariant is proven to respect all known identities of Feynman integrals for graphs. We observe a strong correlation between the tropical and transcendental integrals, which yields a method to approximate unknown Feynman periods.

Collection efficiencies of ionization chambers in pulsed radiation beams: an exact solution of an ion recombination model including free electron effects

Objective. Boag et al (1996) formulated a key model of collection efficiency for ionization chambers in pulsed radiation beams, in which some free electrons form negatively charged ions with a density that initially varies exponentially across the chamber. This non-uniform density complicates ion recombination calculations, in comparison with Boag’s 1950 work in which a collection efficiency formula, f, was straightforwardly obtained assuming a uniform negative ion cloud. Boag et al (1996) therefore derived collection efficiency formulae f′, f″ and f′″ based on three approximate descriptions of the exponentially-varying negative ion cloud, each uniform within a region. Collection efficiencies calculated by Boag et al (1996) using these formulae differed by a maximum of 5.1% relative (at 144 mGy dose-per-pulse with 212 V applied over a 1 mm electrode separation) and all three formulae are often used together. Here an exact solution of the exponentially-varying model is obtained. Approach. The exact solution was derived from a differential equation relating the number of negative ions collected from within some distance of the anode to numbers of ions initially located within that region. Using the resulting formula, f exp, collection efficiencies were calculated for a range of ionization chamber properties and doses-per-pulse, and compared with f, f′, f″ and f″′ values and results from an ion transport code. Main results. f exp values agreed to 5 decimal places with ion transport code results. The maximum relative difference between f exp and f″′, which was often closest to f exp, was 0.78% for the chamber properties and doses-per-pulse studied by Boag et al (1996), rising to 6.1% at 1 Gy dose-per-pulse and 2 mm electrode separation. Significance. Use of f exp should reduce ambiguities in collection efficiencies calculated using the approximate formulae, although like them f exp does not account for electric field distortion, which becomes substantial at doses-per-pulse ≥100 mGy.

Analisis Efisiensi Home Industry Keset di Desa Karangrejo Kecamatan Purwosari Kabupaten Pasuruan

The purpose of this study was to determine the income of the doormat home industry and the level of efficiency or business feasibility in the doormat home industry in Karangrejo Village, Purwosari District, Pasuruan Regency. This type of research is field research (field research). The method used in this study is a quantitative descriptive method of the amount of income and the level of efficiency of the doormat home industry in Karangrejo Village, Purwosari District, Pasuruan Regency. Data collection techniques in this study were questionnaires and interviews. The analytical technique used in this research is the micro approach with the income formula (π=TR-TC) and the business efficiency formula (R/C ratio). The results of this study indicate that; 1) The total net income of the doormat home industry in Karangrejo Village is Rp. 57,235,850, with an average income of Rp. 4,088,275; 2) The intermediate level of efficiency or business feasibility in the doormat home industry is 1,23. The doormat home industry in Karangrejo Village, Purwosari District, Pasuruan Regency, is classified as profitable and feasible to run so that in the future, it has good prospects for its development.

An Efficient K-Factor Formula for Stability Evaluation of Steel Frames with Web-Tapered Members

An Efficient K-Factor Formula for Stability Evaluation of Steel Frames with Web-Tapered Members

Enumeration of non-oriented maps via integrability

In this note, we examine how the BKP structure of the generating series of several models of maps on non-oriented surfaces can be used to obtain explicit and/or efficient recurrence formulas for their enumeration according to the genus and size parameters.

Destratification of thermally stratified water columns by air diffusers

This study aims at improving the understanding in order to optimise an aeration system for artificial destratification to control cyanobacteria growth in the reservoirs. Previous applications for artificial destratification in reservoirs were based on installations based on computational methods, where neither the effect of air bubble size and configuration nor the effect of air density in the bubble plume could be investigated. This study seeks for an optimized design with the help of experimental and numerical analyses. In order to perform experimental studies, a novel water tank enabling the heating/cooling of the water column as desired and a diffuser system were manufactured. During the experimental studies, effect of bubble size, bubble slip velocity, and other parameters of air diffuser on destratification efficiency were investigated. Based on the nondimensional parameters, a new destratification efficiency formula is obtained by the Genetic Algorithm (GA) approach. Additionaly, the hydrodynamics of the water tank during the mixing process by air diffuser was simulated via 3D numerical model and validated with experimental results. The Eulerian multiphase model with the ‘degassing’ boundary condition and k-ω turbulence model are found to be suitable for the purposes of the study. Based on the error analysis of comparisons of the model and observations, the best configuration of air diffuser is proposed, and the numerical model is found to be successful in simulating the destratification of thermally stratified water columns by air diffuser.

Efficient importance analysis methods for structures with distribution parameter uncertainty based on cubature formula

The importance analysis of a structural system with distribution parameter uncertainty can identify key parameters that significantly affect its output performance, thus providing importance guidance for its design and optimization. However, the traditional importance analysis method requires the three-loop Monte Carlo sampling to estimate the importance measurement index of a distribution parameter with such output characteristic values as mean and variance, whose computational cost is too large. To solve this problem, two efficient cubature formula methods based on the surrogate sampling probability density function (SSPDF) for the importance analysis of distribution parameters are proposed: ①the double-loop cubature formula based on the surrogate sampling probability density function (S-DLCF); ②the single-loop cubature formula based on the surrogate sampling probability density function (S-SLCF). The two methods use cubature formulas to efficiently compute the nested mean and variance in the importance measurement index of a distribution parameter, thus solving the problem that the computational effort of propagating parameter uncertainty to output characteristic values depends on parameter dimensionality because of SSPDF. The S-DLCF makes full use of the efficiency and accuracy of the cubature formula to estimate output statistical moments; the S-SLCF simplifies the integral to calculate output moments by expanding the dimensionality of the distribution parameter. The numerical and engineering examples verify the efficiency and accuracy of the two methods for the importance analysis of distribution parameters.

Control of vortex-induced vibration of an elastically mounted cylinder with a pair of porous rods

In this work, the control of vortex-induced vibration (VIV) of an elastically mounted cylinder with a pair of porous rods is numerically investigated at a Reynolds number of 150. To calculate the forces on the moving porous media, an efficient formula based on the momentum theorem is proposed. The porous rods are placed behind the cylinder at an angle of 25°, and the effects of the gap ratio (G) and permeability of the porous rods (Da) on the VIV are studied in detail. Based on the results obtained, it is found that at small G, the VIV is suppressed mainly through the action of shear-layer separation and reattachment. In addition, better performance of VIV control can be achieved by using porous rods with lower Da. As G increases, the porous rods maintain good performance, while solid rods enhance the vibration, the latter being caused by the interaction between the vortices shed from the main cylinder and the rods. The best control effect is achieved by using porous rods at Da = 0.0001 and G = 0.7. The corresponding reductions of vibration amplitude, drag force, and lift force are 85%, 33%, and 84%, respectively.

ANALISIS EFISIENSI DAN EFEKTIVITAS PENERIMAAN RETRIBUSI PASAR SERTA KONTRIBUSINYA TERHADAP PENDAPATAN ASLI DAERAH (PAD) KABUPATEN PEKALONGAN TAHUN 2017-2021

This study uses descriptive statistical methods. The analytical tool used is using the formula for efficiency, effectiveness, and market retribution contributions with 2017-2021 data. The examples used are Market Retribution Revenue Data, Market Levies Collection Cost Data, and Pekalongan Regency Original Regional Revenue (PAD) data obtained from the Industry & Trade Office and the Pekalongan Regency Regional Financial Management Agency.The results of this study indicate that the efficiency level of market retribution revenue in 2017-2021 is classified as very efficient with an average of 3.95%. The level of acceptance of market retribution in 2017-2021 is classified as less effective with an average acquisition of 82.07%. The contribution of market levies to Pekalongan Regency's original regional income (PAD) in 2017-2021 is classified as less large with an average of 1.54%.

Exergy Analysis of a Turboprop Engine at Different Flight Altitude and Speeds Using Novel Consideration

Abstract In this study, exergy efficiency calculations of a turboprop engine were performed together with main performance parameters such as shaft power, specific fuel consumption, fuel flow, thermal efficiency etc., for a range of flight altitude (0–14 km) and flight speeds (0–0.6 Mach). A novel exergy efficiency formula was derived in terms of specific fuel consumption and it is shown that these two parameters are inversely proportional to each other. Moreover, a novel exergy efficiency and thermal efficiency relation was also derived. The relationship showed that these two parameters are linearly proportional to each other. Exergy efficiency of the turboprop engine was found to be in the range of 23–33%. Thermal efficiency of the turboprop engine was found to be around 25–35%. Exergy efficiency is higher at higher speeds and altitude where the specific fuel consumption is lower. Conversely, exergy efficiency of the engine is lower for lower speeds and altitude where the specific fuel consumption is higher.

Design of lossy three‐element networks with optimization efficiency

AbstractLumped passive elements are usually lossy because parasitic resistances dissipate the power transferred from the source to the load; thus, this loss influences the performance of the matching network. Furthermore, the impedances that need to be matched are usually complex‐valued. In this paper, we described an optimization design method for lossy three‐element network to achieve impedance matching between complex source and load impedances. We first determined the efficiency formulas for lossy and T networks via a generalized quality‐based equation. Next, two methods were introduced to design the lossy and T networks with maximum efficiency. Finally, to validate the effectiveness of the designed lossy three‐element networks, we conducted a series of numerical analysis and simulations, which indicates that the designed lossy and T networks exhibits excellent impedance matching performance at the desired frequency. For some instances, the lossy network with three elements exhibits a higher efficiency than a multistage matching network with more elements.

Clarification of the Supercooling and Heat Storage Efficiency Calculation Formula for Shape-Stabilized Phase Change Materials.

It is essential to determine the heat storage efficiency of shape-stabilized phase change materials (ss-PCMs). In two published articles, the formula for heat storage efficiency is presented using two distinct equations. Using the two equations, the calculated values for heat storage efficiency revealed significant discrepancies. The outcomes cannot be compared. The evaluation of heat storage efficiency has a substantial impact on the practical application of PCMs and serves as a performance benchmark for the PCM samples that have been tested. In this paper, the correct equations for calculating the efficiency of heat storage are presented. Furthermore, it is essential to note that the methods used to calculate the supercooling value are not straightforward. Consequently, this paper clarified the correct formula and/or method for determining the supercooling value and heat storage efficiency of ss-PCMs.

Artificial Neural Networks for Microwave Computer-Aided Design: The State of the Art

This article presents an overview of artificial neural network (ANN) techniques for a microwave computer-aided design (CAD). ANN-based techniques are becoming useful for performing forward/inverse modeling for active/passive components to enhance a circuit design. With measured or simulated data of microwave devices, ANNs can be trained to learn relevant microwave relationships, which are, otherwise, computationally expensive or for which efficient analytical formulas are not available. Fundamental concepts of the ANN structure and training, such as feedforward neural networks (FFNNs), recurrent neural networks (RNNs)/dynamic neural networks (DNNs)/time-delay neural networks (TDNNs), deep neural networks, and neural network training and extrapolation, are described. Knowledge-based neural networks (KBNNs) are described for improving the accuracy and reliability of modeling and design optimization. Various advanced ANN techniques, such as neuro-transfer function (neuro-TF) modeling, neural network inverse modeling, and deep neural network modeling, are discussed. The existing and emerging applications of ANN in microwave CAD are identified, such as electromagnetic (EM)/multiphysics modeling, modeling of nonlinear circuits and transistors, filter design, very large-scale integration (VLSI) interconnects, oscillator, transmitter and receiver modeling, and CAD applications in such as gallium nitride (GaN) high electron-mobility transistor (HEMT), wireless power transfer (WPT), microelectromechanical system (MEMS), and substrate-integrated waveguide (SIW).