Calculation Of Energy Loss Research Articles

Reconfiguration and Capacitor Placement Simultaneously for Energy Loss Reduction Based on an Improved Reconfiguration Method

Network reconfiguration and capacitor placement have been widely employed to reduce power losses and maintain voltage profiles within permissible limits in distribution systems. Reconfiguration method proposed in this paper is based on a simple branch exchange method of single loop. In this simple method of branch exchange, loops selection sequence affects the optimal configuration and the network loss. Therefore, this method has been improved by optimizing the sequence of loops selection for minimizing the energy losses in this paper. Also, a joint optimization algorithm is proposed for combining this improved method of reconfiguration and capacitor placement and therefore maximum loss reduction. For more practical application of the proposed method, different load patterns are considered and a fast method of total energy loss calculation is employed for the economic optimization of energy losses during the planning horizon. Discrete genetic algorithm (GA) is used to optimize the location and size of capacitors and the sequence of loops selection. In fact, the capacitor sizes have been considered as discrete variables. Simulated annealing (SA) is also applied to compare the performance of convergence. The proposed algorithm is effectively tested on a real life 77-bus distribution system with four different kinds of load patterns.

The T-Matrix method in electron energy loss and cathodoluminescence spectroscopy calculations for metallic nano-particles

In this paper, we present the application of the T-Matrix method (TMM) for the calculation of Electron Energy Loss Spectra (EELS), cathodoluminescence spectra (CLS) and far-field patterns produced by metallic nano-particles. Being frequently used in electromagnetic scattering calculations, the TMM provides an efficient tool for EELS calculations as well and can be employed, e.g. for the investigation of nano-antennas.

Energy loss calculations of moving defects for general holographic metrics

We extend the ideas of using AdS/CFT to calculate energy loss of extended defects in strongly coupled systems to general holographic metrics. We find the equations of motion governing uniformly moving defects of various dimension and determine the corresponding energy loss rates in terms of the metric coefficients. We apply our formulae to the specific examples of both bulk geometries created by general Dp-branes, as well as to holographic superfluids. For the Dp-branes, we find that the energy loss of our defect, in addition to the expected quadratic dependence on velocity, depends on velocity only via an effective blueshifted temperature - despite the existence of a microscopic length scale in the theory. We also find, for a certain value of p and dimension of the defect, that the energy loss has no dependence on temperature or velocity other than the aforementioned quadratic dependence on velocity. For the superfluid example, we find agreement with previous results on the existence of a cutoff velocity, below which the probe experiences no drag force. For both examples we can easily extend the equations of motion and energy loss to defects of larger dimension.

Medium-induced color flow softens hadronization

Medium-induced parton energy loss, resulting from gluon exchanges between the QCD matter and partonic projectiles, is expected to underly the strong suppression of jets and high-$p_T$ hadron spectra observed in ultra-relativistic heavy ion collisions. Here, we present the first color-differential calculation of parton energy loss. We find that color exchange between medium and projectile enhances the invariant mass of energetic color singlet clusters in the parton shower by a parametrically large factor proportional to the square root of the projectile energy. This effect is seen in more than half of the most energetic color-singlet fragments of medium-modified parton branchings. Applying a standard cluster hadronization model, we find that it leads to a characteristic additional softening of hadronic spectra. A fair description of the nuclear modification factor measured at the LHC may then be obtained for relatively low momentum transfers from the medium.

쓰레기 관로운송 시스템의 운송에너지 손실에 관한 수치해석적 연구

This paper describes energy loss in a pipe line of refuse collecting system. Analysis of energy loss in a pipe line is the decisive factor in a design of refuse collecting system. Using the results of energy loss analysis, we can determine the power of turbo-blower. The flow characteristics of the pipe line with refuse bags were analyzed by three-dimensional CFD. The refuse bag is modeled by using the shape obtained from profile measurement. Friction factors were calculated with changing the refuse bag size, mixing ratio and Reynolds number. And drag coefficients were calculated using the CFD results. From the results we can calculate energy loss in a pipe line of refuse collecting system and predict the capacity of turbo-blower.

Density functional theory study of ultrasmall diameter (2,2) boron nitride, silicon carbide, and carbon nanotubes

AbstractWe present a first principles calculation on the electronic structure and optical properties of ultrasmall‐diameter (2,2) boron nitride, silicon carbide, and carbon nanotubes (BNNT, SiCNT, and CNT) by using full potential linear augmented plane wave (FP‐LAPW) and pseudo potential plane wave (PP‐PW) methods. The atomic geometries of all considered models are optimized. Calculations of optical spectra are performed under electric fields polarized both parallel and perpendicular with respect to the nanotube (NT) axis. Our results show that the dielectric function is anisotropic and it is revealed that (2,2) SiCNT would be better dielectric material than (2,2) BNNT. We have calculated the first, second and third optical transitions for the considered models. The value of the optical gap for (2,2) BNNT is obtained much larger than that of (2,2) SiCNT and (2,2) CNT. The results show that contrary to the (2,2) CNT being metallic, the (2,2) BNNT, and (2,2) SiCNT are wide indirect gap semiconductors. We also present the energy loss function; in this case the intertube interactions play an important role with respect to the optical spectroscopy. Our results revealed that unlike the dielectric function, the calculated energy loss function show rather weak anisotropy.

Investigation of ultraviolet optical properties of semiconducting-enriched and metal-enriched single-walled carbon nanotube networks using spectroscopic ellipsometry

The ultraviolet optical properties of semiconducting-enriched and metallic-enriched single-walled carbon nanotube (semi-enriched and m-enriched SWCNT) networks were studied using spectroscopic ellipsometry. According to calculated energy loss function, the energy loss peak assigned to the maximum intensity of π-plasmon energy was found to increase from 4.5 eV to 5.0 eV as SWCNT network composition was changed from m-SWCNT enriched to semi-SWCNT enriched. These results clearly demonstrate that the dielectric response in the 4-6 eV range is sensitive to changes in the surrounding dielectric environment depending on the semi-/m-SWCNT content. Therefore, the spectral shift of this energy loss is attributed to the enhanced electron confinement by the presence of the surface plasmon due to a small amount of m-SWCNT, which is an important phenomenon at the SWCNT network.

The Gauge-String Duality and Heavy Ion Collisions

I review at a non-technical level the use of the gauge-string duality to study aspects of heavy ion collisions, with special emphasis on the trailing string calculation of heavy quark energy loss. I include some brief speculations on how variants of the trailing string construction could provide a toy model of black hole formation and evaporation. This essay is an invited contribution to "Forty Years of String Theory" and is aimed at philosophers and historians of science as well as physicists.

On the propagation times and energy losses of cosmic rays in the heliosphere

[1] We present calculations of the propagation times and energy losses of cosmic rays as they are transported through the heliosphere. By calculating these quantities for a spatially 1D scenario, we benchmark our numerical model, which uses stochastic differential equations to solve the relevant transport equation, with known analytical solutions. The comparison is successful and serves as a vindication of the modeling approach. A spatially 3D version of the modulation model is subsequently used to calculate the propagation times and energy losses of galactic electrons and protons in different drift cycles. We find that the propagation times of electrons are longer than those of the protons at the same energy. Furthermore, the propagation times are longer in the drift cycle when the particles reach the Earth by drifting inward along the heliospheric current sheet. The calculated energy losses follow this same general trend. The energy losses suffered by the electrons are comparable to those of the protons, which is in contrast to the generally held perception that electrons experience little energy losses during their propagation through the heliosphere.

Quenching and tomography from the RHIC to the LHC

We compare fully perturbative and fully nonperturbative pictures of high-pT energy loss calculations to the first results from the LHC. While oversuppressed compared to published ALICE data, parameter-free pQCD predictions based on the WHDG energy loss model constrained to RHIC data simultaneously describe well the preliminary CMS hadron suppression, ATLAS charged hadron v2, and ALICE D meson suppression; we also provide for future reference WHDG predictions for B meson RAA. However, energy loss calculations based on AdS/CFT also qualitatively describe well the RHIC pion and non-photonic electron suppression and LHC charged hadron suppression. We propose the double-ratio of charm to bottom quark RAA as a qualitative distinguisher between these two energy loss pictures.

Heavy quarks in the presence of higher derivative corrections from AdS/CFT

We use the gauge–string duality to study heavy quarks in the presence of higher derivative corrections. These corrections correspond to the finite-coupling corrections on the properties of heavy quarks in a hot plasma. In particular, we study the effects of these corrections on the energy loss and the dissociation length of a quark–antiquark pair. We show that the calculated energy loss of heavy quarks through the plasma increases. We also find in general that the dissociation length becomes shorter with the increase of coupling parameters of higher curvature terms.

How to improve poor system efficiencies of ESP installations controlled by surface chokes

Electrical submersible pumping is the most inflexible of any artificial lift system because a specific ESP pump can only be used in a definite, quite restricted range of pumping rates. If it is used outside the specified range, pump and system efficiencies rapidly deteriorate and eventually mechanical problems leading to a complete system failure develop. When serious deviation from the design production rate is experienced, the possible solutions are (a) running a different pump with the proper recommended operating range, or (b) using a variable speed drive (VSD) unit. However, in case the ESP system produces a higher than desired liquid rate, a simple and frequently used solution is the installation of a wellhead choke. The wellhead choke restricts the pumping rate and forces the ESP pump to operate within its recommended liquid rate range. This solution, of course, is very detrimental to the economy of the production system because of the high hydraulic losses across the choke that cause a considerable waste of energy. The paper utilizes NODAL analysis to investigate the negative effects of surface production chokes on the energy efficiency of ESP systems as compared to the application of VSD drives. The power flow in the ESP system is described and the calculation of energy losses in system components is detailed. Based on these, a calculation model is proposed to evaluate the harmful effects of wellhead choking and to find the proper parameters of the necessary VSD unit. By presenting a detailed calculation on an example well using the proposed model the detrimental effects of wellhead choking are illustrated and the beneficial effects of using a VSD drive are presented. Using data of a group of wells placed on ESP production a detailed investigation is presented on the field-wide effects of choking. The energy flows and the total energy requirements are calculated for current and optimized cases where VSD units providing the required electrical frequencies are used. Final results clearly indicate that substantial electric power savings are possible if production control is executed by VSDs instead of the present practice of using surface chokes.

Viscosity of liquid suspensions with fractal aggregates: Magnetic nanoparticles in petroleum colloidal structures

Abstract New physical model is presented resulting in a simple formula for the dependence of viscosity η of colloidal liquid solution on the shear rate G applicable to a wide variety of systems including complex natural liquids like petroleum. The principal point of the model is the fractal nature of colloid particle aggregates present in the liquid. Such aggregates are experimentally detected now in non-Newtonian liquids. The model is based on calculation of energy loss on colloidal particle aggregate of fractal structure localized in the flow of liquid with shear rate. We have performed the viscosity measurement experiments which confirmed successfully the developed physical model. Also, we demonstrate experimentally that petroleum colloidal particles and magnetic iron oxide nanoparticles can form composite fractal-like aggregates in natural petroleum materials. Our model can explain both the non-Newtonian properties of petroleum and sensitivity of petroleum viscosity to external magnetic fields.

Nonperturbative shell correction to the Bethe-Bloch formula for the energy losses of fast charged particles

A simple method including nonperturbative shell corrections has been developed for calculating energy losses on complex atoms. The energy losses of fast highly charged ions on neon, argon, krypton, and xenon atoms have been calculated and compared with experimental data. It has been shown that the inclusion of the non-perturbative shell corrections noticeably improves agreement with experimental data as compared to calculations by the Bethe-Bloch formula with the standard corrections. This undoubtedly helps to reduce the number of fitting parameters in various modifications of the Bethe-Bloch formula, which are usually determined semiempirically.

Energy Loss at Drops using Neuro Solutions

Energy dissipation in drops has been investigated by physical models. After determination of effective parameters on the phenomenon, three drops with different heights have been constructed from Plexiglas. They have been installed in two existing flumes in the hydraulic laboratory. Several runs of physical models have been undertaken to measured required parameters for determination of the energy dissipation. Results showed that the energy dissipation in drops depend on the drop height and discharge. Predicted relative energy dissipations varied from 10.0% to 94.3%. This work has also indicated that the energy loss at drop is mainly due to the mixing of the jet with the pool behind the jet that causes air bubble entrainment in the flow. Statistical model has been developed to predict the energy dissipation in vertical drops denotes nonlinear correlation between effective parameters. Further an artificial neural networks (ANNs) approach was used in this paper to develop an explicit procedure for calculating energy loss at drops using NeuroSolutions. Trained network was able to predict the response with R 2 and RMSE 0.977 and 0.0085 respectively. The performance of ANN was found effective when compared to regression equations in predicting the energy loss. Keywords—Air bubble, drop, energy loss, hydraulic jump, NeuroSolutions

Completely Inelastic Collision to Confirm Maximum Punch Pressure Force of Cold Pressure Welding

The maximum punch pressure force (TMPPF) of cold welding pressure affects not only the performance of the welding bonding but also the amount of the area of welding bonding. If punch force is more bigger, it may be take place cracks, stress concentration and welding concave pits, which affect application of materials and increase incidence of faults. The process that punch pressure of cold welding pressure applied on sheet materials to attain welding bonding is simplified beam in cold pressure welding. Under normal circumstances it is an important method to TMPPF by the manner of experiment, but the method to attain TMPPF is limited. In the paper completely inelastic collision theory is applied to explain the process of cold welding pressure, the theory of completely inelastic collision offers principle theory to attain TMPPF. In this paper, two supposes are put forward, on the basis of two supposes the critical velocity is attained. At the same time, critical kinetic momentum or critical kinetic energy will be attained. On the basis of the law of conservation of energy, energy balance equation is attained, which will drop in calculating difficulty of the non-linear process of cold pressure welding and decrease calculated amount. In this paper on the basis of the process of collision all phases are analyzed. Indeed elastic-plastic deformation phase is completely inelastic collision phase, and from point of view of collision to calculate energy loss. At the same time, to suppose other plate is utter stiff can attain critical velocity, thus, to achieve the equation of TMPPF.

Ab initio study of dielectric response of rippled graphene

Ab initio calculations of dielectric function and electron energy loss (EEL) function of periodically rippled armchair-edged graphene were performed in the framework of the random-phase approximation. The bending of graphene was found to remove restrictions on the electron transitions being forbidden in the flat graphene for certain light polarization. As a result, new peaks appear in the optical absorption spectrum and EEL spectrum of rippled graphene. Energy position, intensity, and width of the peaks are sensitive to the height of out-of-plane graphene bending that can be used in construction of graphene-based materials with variable transparency window.

DATA EVALUATION ACQUIRED TALYS 1.0 CODE TO PRODUCE 111In FROM VARIOUS ACCELERATOR-BASED REACTIONS

The Indium-111 physical-decay parameters as a β-emitter radionuclide show some potential for radiodiagnostic and radiotherapeutic purposes. Medical investigators have shown that 111 In is an important radionuclide for locating and imaging certain tumors, visualization of the lymphatic system and thousands of labeling reactions have been suggested. The TALYS 1.0 code was used here to calculate excitation functions of 112/114–118 Sn+p , 110 Cd +3 He , 109 Ag +3 He , 111–114 Cd+p , 110/111 Cd+d , 109 Ag +α to produce 111 In using low and medium energy accelerators. Calculations were performed up to 200 MeV. Appropriate target thicknesses have been assumed based on energy loss calculations with the SRIM code. Theoretical integral yields for all the latter reactions were calculated. The TALYS 1.0 code predicts that the production of a few curies of 111 In is feasible using a target of isotopically highly enriched 112 Cd and a proton energy between 12 and 25 MeV with a production rate as 248.97 MBq·μA-1 · h-1. Minimum impurities shall be produced during the proton irradiation of an enriched 111 Cd target yielding a production rate for 111 In of 67.52 MBq· μA-1 · h-1.

Formula omitted] azimuthal anisotropy in Au+Au collisions at [formula omitted] from PHENIX: collision energy and path-length dependence of jet-quenching and the role of initial geometry

The azimuthal anisotropy of high p T particle production in heavy ion collisions is a sensitive probe of the jet quenching mechanism. Recent PHENIX measurements for Au+Au collisions at s N N = 200 GeV show a π 0 v 2 signal that exceeds the pQCD energy loss calculations up to p T ∼ 10 GeV/c , challenging the traditional perturbative picture of the energy loss process. Here, we present an update and details of that measurement, as well as new high p T measurements at s N N = 62 and 39 GeV. These measurements not only provide an important constraint for understanding the path-length dependence of jet energy loss and the role of initial collision geometry, but also allow a search for the onset of jet quenching as s N N is varied.

Latest Technological Advances in Rod Pumping Allow Achieving Efficiencies Higher Than With ESP Systems

Summary Two of the most important artificial-lift methods applied in oil wells are sucker-rod pumping (SRP) and electrical submersible pumping (ESP, with thousands of installations all over the world. Their operational features and application ranges are quite different, but in many cases either of them can be used in a given well. The final selection of the proper method has to be on the basis of energy efficiency, and the one requiring the least amount of surface power input is selected. This paper provides the necessary background for evaluating the effectiveness of the two lift methods investigated and for pinpointing the requirements of achieving maximum power efficiency of artificial lifting. The power flow in the pumping system is investigated, and the sources of power losses, along with their usual ranges, are described. The overall power efficiency of the system is defined by a simple formula that provides the necessary insight into the main components of the power losses occurring in different system elements. A thorough investigation of the efficiency components allows one to find the factors that most markedly influence the total system's power requirement. As shown in the paper, the most important requirement for achieving maximum effectiveness is the proper choice of the pumping mode (i.e., the combination of plunger size, stroke length, and pumping speed). The calculation of energy losses in the components of the ESP system is detailed, and the relative importance of the individual losses is shown. Because the components of the ESP system are connected in series, a relatively simple formula can be used to describe the effect of electrical and hydraulic losses on the efficiency of the total system. The terms of the final formula were investigated for their importance and contribution to the overall effectiveness of the ESP system. Results of this investigation provide crucial information that explain how to design an ESP system that provides the highest power efficiency. The practical use of the proposed calculation models is illustrated by presenting an example case where a relatively high liquid rate (1,300 B/D) from the same well is produced by rod pumping and by ESP. Detailed installation designs resulted in several different operation modes for both SRP and ESP. The paper demonstrates that using the latest technologies (e.g., high-strength sucker-rod connections), SRP can compete successfully with ESP installations by attaining higher energy efficiencies.