Order Modes Research Articles

Investigation of the unsteady pressure fluctuation mechanism in a regenerative flow pump based on proper orthogonal decomposition

The regenerative flow pump (RFP) derives its name from the circular flow pattern akin to a vortex. However, the presence of numerous vortices results in highly turbulent flow and pressure fluctuation. This study delves into the characteristics of the internal unsteady flow in two distinct RFP models featuring different blade shapes. Numerical simulations are employed to obtain the pressure field, which is subsequently scrutinized using the proper orthogonal decomposition (POD) method. The results show that the average pressure in the peripheral direction undergoes minimal variation during the flow developing stage, experiences a sharp increase in the fully developed stage, and finally exhibits substantial changes in the stripper. The transient pressure in the time domain fluctuates periodically, and the dominant blade passing frequency in the frequency domain demonstrates a similar trend along the circumferential direction as the average pressure. Moreover, the fluctuating intensity of pressure diminishes along the impeller's rotating direction but intensifies significantly in the stripper. Comparative analysis indicates that the exchange intensity is influenced by the flow at different developmental stages, and the exchange flow conditions could reflect the fluctuating intensity. Furthermore, the study reveals that the frequency amplitude of the time coefficient gradually decreases as the mode order increases. The first and second modes exhibit a gradually changing trend associated with pressure increase patterns, whereas the third and fourth modes highlight the emergence of localized modulation phenomena linked to exchange flow. Thus, the POD method offers a unique perspective for comprehending the flow mechanisms within RFPs.

Modal analysis and higher order mode suppression of a high impedance surface-based bowtie antenna

Abstract The present work studies the design of a high impedance surface (HIS)-based bowtie antenna in the framework of characteristic mode analysis (CMA) and proposes the method of higher order mode suppression. A triangular-elliptical bowtie antenna operating in the frequency range of 1.6–6 GHz is designed. The radiating and higher order modes of the proposed antenna are identified using CMA, and an HIS structure is used to enhance the desired mode and to suppress the higher order mode in order to get high gain, good front-to-back ratio (FBR), and stable radiation characteristics. The final designed HIS-based bowtie antenna gives stable radiation patterns from 1.7 to 5.5 GHz with a maximum boresight gain of 10.5 dB. Also, gain from 6.5 to 12 dB and FBR from 8 to 18 dB are obtained in the operating bandwidth. The proposed antenna features the advantages of low profile, wideband and high boresight gain making it suitable for ground-penetrating radar applications.

BECI System of Business English Reading and Writing

Purpose: This study puts forward the BECI system under the background of Chinese new liberal arts construction and the guidance of postmodern philosophy and the blended teaching mode in order to sustainably improve students’ Business English Reading and Writing ability and cultivate Business English compound talents who meet the market demand. Theoretical framework: The research makes use of post-modern philosophy and blended teaching mode to explore the BECI system. Design/ methodology/ approach: The BECI system teaching mode integrates traditional teaching and digital teaching, and uses information technology, online and offline, multi-modal teaching and process assessment mechanism to comprehensively improve students’ participation and subjective learning status, and cultivate their good study habits. Findings: BECI system is market-demand-oriented, student-centered and teacher-scaffolded, which includes business knowledge, English knowledge, cross-cultural knowledge and ideological and political knowledge, and advocates the mutual promotion of Business English Reading (input) and Business English Writing (output). Research, Practice & Social Implications: The research not solely solves some problems, such as complicated teaching content and low learning efficiency of students, Business English Reading and Writing facing with, but also endows learners with the sustainable Business English Reading and Writing ability and good study habits.

Finite element analysis of the cervical spine: dynamic characteristics and material property sensitivity study

The study aimed to investigate the dynamic characteristics of the cervical spine and determine the effect of the material properties of the cervical spinal components on it. A finite element model of the head-cervical spine was developed based on CT scan data, and the first six orders of modes (e.g. flexion-extension, lateral bending, and vertical, etc.) were verified by experimental and simulation studies. The material sensitivity study was conducted by varying elasticity modulus of cervical hard tissues (cortical bone, cancellous bone, endplates, and posterior elements) and soft tissues (intervertebral disc and ligaments). The results showed that increasing the elastic modulus of ligaments by 4 times increased the natural frequency by 77%, while increasing that of cancellous bone by 4 times only increased the natural frequency by 6%. In the axial mode, the cervical spine had not only axial deformation but also anterior-posterior deformation, with the largest deformation located at the intervertebral disc C6-C7. Decreasing the elastic modulus of a component in soft tissues by 80% increased modal displacement by up to 62%. The material properties of the intervertebral discs and ligaments had opposite effects on the modal displacement and deformation of the cervical spine. Low cervical discs were more susceptible to injury in a vertical vibration environment. Cervical spine dynamics were more sensitive to soft tissue material properties than to hard tissue material properties. Disc degeneration could reduce the range of vibratory motion of the cervical spine, thereby reducing the ability of the cervical spine to cushion head impacts.

The role of soluble guanylate cyclase stimulator riociguat in preventing the development of reperfusion lung injury after balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension

Aim. To evaluate the effect of prior administration of the soluble guanylate cyclase stimulator riociguat on the incidence and severity of reperfusion lung injury after balloon pulmonary angioplasty (BPA) in patients with inoperable form of chronic thromboembolic pulmonary hypertension (CTEPH).Materials and methods. 70 patients with inoperable CTEPH were included in the study. Patients were divided into 2 groups: Group 1 (n=41) – patients who had received PAH-specific therapy with riociguat at the time of BPA, Group 2 (n=29) – patients who underwent BPA without prior administration of riociguat. In the postoperative period all the patients underwent noninvasive artificial ventilation in continuous positive airway pressure mode in order to prevent the development of reperfusion damage of lungs.Results. Patients of group 1 received treatment with riocigiat for 6 months. At the time of BPA patients of both groups were matched for hemodynamic characteristics. In group 1, reperfusion edema above grade 1 occurred in 17.1% of patients, in group 2 – in 20.7% of patients, p=0.702. In group 1, manifestations of grade 3 reperfusion edema were found in 9.8% patients vs. 6.9% patients in group 2, (p=0.638). None of the patients in both groups had grade 4 or 5 reperfusion edema. Values of the index predicting the probability of reperfusion injury (PEPSI) were not significantly different in the group of patients who were pretreated with riociguat and in the group of patients who did not get PAH-specific therapy (p=0,588).Conclusion. There was no reliable evidence that administration of riociguat in recommended doses at least 6 months before BPA results in additional reduction in the incidence and severity of reperfusion pulmonary edema in patients with inoperable CTEPH.

Experiences and Sense-Making Processes of Online Teaching Internship: A Master of Teaching Programme

Teaching requires a student-teaching internship for the license and registration, usually completed from the face-to-face and on-campus components. However, due to the covid-19 pandemic, many classrooms have switched to online platforms, regardless of the levels. This study aims to understand student-teachers’ experiences of an online-based student-teaching internship and how such internships influence the sense-making processes of student-teachers in online school environments. In line with the self-efficacy theory and social cognitive career and motivation theory, the case study method was used to invite a group of Master of Arts in Teaching students (a total of 18) to share their experiences and sense-making processes of their online student-teaching internship. Semi-structured interviews, focus group activities, and member-checking interviews were used to collect data from the participants. Based on the qualitative data, three themes were categorised: 1) positive experiences, 2) technology education is the trend, and 3) preparation for online classroom environments. The study may provide support or ideas to university leaders, supervisors, department heads, student-teachers, and policymakers to reform and polish their teaching qualification programmes with different types of delivery modes in order to meet the needs and educational trends of the coming decades. Keywords: case study, Master of Arts in Teaching, online learning, self-efficacy, sense-making process, social cognitive career, motivation theory, student-teaching internship

Radial sandwich radial-bending composite transducer designed based on acoustic black hole theory

A novel radial sandwich radial bending composite transducer is proposed based on the increasing amplitude of bending waves in the structure of an acoustic black hole (ABH). The transducer consists of a radial sandwich circular ring transducer and an outer acoustic black hole structure. The existence of the ABH structure realizes the conversion between radial vibration and bending vibration of the transducer, and improves the acoustic radiation performance of the transducer. Based on the one-dimensional acoustic black hole bending vibration theory, the bending vibration equation of the circular ABH structure is given. An analytical model of the ABH structure bending vibration is established by using the method of geometrical-acoustics, and the eigen frequency of its bending vibration is given. The relationship between the electromechanical conversion performance and the size of the transducer is discussed by using the finite element method, and the results show that when the eigen frequency of the bending vibration of the ABH structure is close to the resonant frequency of the transducer, the electromechanical coupling coefficient of the transducer reaches a maximum value. The radiation sound pressure field, radiation sound intensity, and radiation directionality of the transducer in the air are also analyzed by the finite element method. The results indicate that the presence of the ABH structure can improve the electromechanical conversion performance of the bending vibration of the transducer, enhance the acoustic radiation performance of the transducer, make the transducer exhibit radiation directionality and the lower order of the bending vibration mode of the ABH structure, the stronger radiation directionality of the transducer towards the left side and the right side. Finally, in order to verify the accuracy of the simulation and theory, we made a prototype transducer and carried out the experimental test of transducer electrical impedance and vibration mode. The measured results are in good agreement with the simulation results. The displacement distribution of the radiation surface of the transducer at resonance frequency is measured, which verifies the bending vibration mode of the ABH structure. This type of transducer is expected to be used as acoustic projector in the air or water.

Synthesis Design of In-Line Pseudoelliptic SISL Bandpass Filter Employing Non-Resonating Mode in Low-Loss Patch Resonators

This paper presents a novel type of patch resonator suitable for the design of high selectivity in-line pseudoelliptic bandpass filters (BPFs) based on a substrate-integrated suspended line (SISL) platform. The proposed structure is a rectangular patch resonator that allows the propagation of the fundamental mode and high order modes. By controlling the position of input and output feedlines, the proposed resonators can provide both a reflection and a transmission zero simultaneously. Thus, a pole-zero pair can be produced (behaving as a singlet). The position of poles and zeros can be fully controlled by varying the position and orientation of the feeding lines. To verify the proposed concept, a detailed study about the behavior of the patch singlet and a validated third-order filter BPF with three TZs ( canonical BPF) located in the lower and upper passband is presented in this brief. The measured results exhibit an extended stopband with rejection better than 58 dB in the lower passband and 40 dB in the upper passband. The tested return losses and insertion loss are better than -15.7 dB and 1.31 dB, respectively.

Generation of spatial combs digitized by orbital angular momentum

Shaping the transverse spatial domain of light has been experiencing recent growth in attention for its applications in optical tweezing, microscopy, communications, and quantum information sciences. The orbital angular momentum (OAM) of light is a transverse physical property that functions as a viable basis for many of such applications. While fields containing a single OAM mode order have extensively been used, fields containing a broad, discrete, and equally spaced OAM spectrum—an OAM comb—has largely been unexplored due to a lack of viable creation methods. Much like how frequency combs enabled myriad applications, it is conceivable that OAM combs would likewise enable further opportunities or expand upon single-OAM applications. For instance, an OAM comb may pave the way for more sophisticated particle manipulation, object detection, and pump shaping for high-dimensional spatial-mode entanglement. Here, we create four OAM combs with rectangular, sinusoidal, sinc, and Gaussian OAM spectral distributions using multiplane light conversion, which only involves phase modulations (hence is inherently lossless) and allows for improved tailoring of the spatial shape. The verification of such combs is done qualitatively by analyzing their propagation evolutions and quantitatively by employing a mode sorting technique—both exhibiting good agreement with user specifications and simulations. The scattering losses of all four combs were measured to be minimal, ranging from 0.66 to 1.04 dB.

Predicting the Heat Generation Rate in Large Format Pouch-Type Lithium-Ion Battery Cells for Automotive Applications

Accurate prediction of the heat generation rate of lithium ion batteries is critical for driving towards a cost effective and efficient design of a thermal management system for various applications.[1, 2] because of the increase in battery cell dimensions associated with an increase in battery cell capacity to drive towards a reduction in range anxiety for automotive applications, as well as more aggressive operating conditions that are typically seen in the automotive industry, such as direct current fast charge and sustained driving under load, heat generation at the cell level must be considered as spatially nonuniform during operation. Proper design of the thermal management system requires prediction[3] of the heat generation of the battery cell in both a lumped fashion for system sizing, as well as a distributed mode in order to focus cooling appropriately to decrease local temperature extremes. Local temperature extremes can adversely affect the aging of the battery cell due to the non-uniformities in electrochemical utilization of the active material, increased local reaction rates, and increased mechanical stresses in active materials.In this work, we detail our efforts to characterize the heat generation[4] of a battery cell under a variety of operating conditions, quantify the impact of temperature non-uniformities[5] on the aging of the battery cell, and experimentally[6, 7] evaluate the localized aging in the battery electrodes based on local temperature conditions. Here, we will describe the modeling methods developed to link operating conditions, aging, and heat generation with the electrochemical performance of the battery cell. A discussion of the model performance for relevant automotive applications will also be included.References M. Song, Y. Hu, S.-Y. Choe and T. R. Garrick, J Electrochem Soc, 167, 120503 (2020).Y. Hu, S.-Y. Choe and T. R. Garrick, Electrochim Acta, 362, 137124 (2020).M. Song, Y. Hu, S.-Y. Choe and T. R. Garrick, J Electrochem Soc, 169, 070502 (2022).Y. Hu, S.-Y. Choe and T. R. Garrick, Applied Thermal Engineering, 189, 116709 (2021).Y. Hu, S.-Y. Choe and T. R. Garrick, J Power Sources, 532, 231350 (2022).U. Janakiraman, T. R. Garrick and M. E. Fortier, J Electrochem Soc, 167, 160552 (2020).T. R. Garrick, J. Gao, X. Yang and B. J. Koch, J Electrochem Soc, 168, 010530 (2021).

MRAC with SMC Applied to Lateral Control of a Fixed-Wing MAV

Abstract: This paper presents a PD control law with adaptive gains with the MIT (Massachusetts Institute Technology) rule with different sliding modes; that is, the MIT rule has been designed with is known in the literature with first order sliding mode, second order sliding mode and high order sliding mode (HOSM) to obtain a better gain scheduling taking advantage the sliding modes techniques-the PD control law with adaptive gains that is designed for the lateral dynamics of a fixed-wing MAV. To apply the methodology of the model reference adaptive control (MRAC), sometimes called model reference adaptive system (MRAS), to the adaptive gains of the PD control, a sliding manifold is proposed considering the output of the lateral dynamics and with the output of the reference model.

Vertical crack identification of arch dam under underwater explosion based on mode transition

The failure process of concrete arch dam subjected to underwater explosion has been the research hotspot in recent years, however, there is a lack of an effective method to identify the crack in dam body. To solve this problem, the crack identification of arch dam caused by underwater explosions has been studied in this paper. Firstly, an analysis method to identify the vertical crack in dam body is proposed, according to a comparison of the modal characteristics of the arch dam with and without crack. Secondly, the reliability of the proposed method is verified by a small-scale arch dam that cracking along the crown beam attacked by foundation explosion. The modal change of the dam induced by cracking is captured in both experiment and numerical simulation. Thirdly, this method is applied to analyze the influence of vertical crack on the modal of a 240 m high arch dam. Some findings need be noted as follows: vertical cracks lead to modal transition of arch dam of two adjacent dense modes, such as orders between 4 and 5, 7 and 8, and 11 and 12 respectively in this case, the ratio of modal transition is 6.04% in the first 8 modes and it is 14.1% in the first 12 modes; The effect of cracks on the mode of arch dam is related to the spatial position of the vibration mode peak, the nearer the two are, the more significant the change in that order of mode is. This finding indicates that the vertical cracks may lead to mode transition or mode loss of arch dams, it should be considered that the change of arch-cantilever system vibration mode sequence in the identification of the crack of arch dam caused by underwater explosion.

Mode-order conversion in a Mach-Zehnder interferometer based on Chern insulators.

Mode-order conversion devices can provide a flexible platform to achieve mode coupling and optimizing in mode division multiplex (MDM) that can eliminate the restrain of capacity and density in photonic integration and communication. However, mode-order converters based on traditional photonic crystal (PC) waveguides are susceptible to defects, which always render device incapacitation in mode-order conversion. Herein, a mode converter designed by the Mach-Zehnder interferometer (MZI) structure is proposed to manipulate the conversion of topological edge states (TESs) based on Chern insulators consisting of gyromagnetic PCs. The back-and-forth conversion between fundamental and high-order modes is numerically demonstrated based on phase modulation in our proposed device, in which each mode can be immune to defects. This unique approach for converting the mode order of TES exploits a new perspective in MDM to design a high-performance multimode device, leading to potential applications in photonic integrated circuits (PIC), on-chip processors, and optical fiber communication.

High-order orbital angular momentum mode-based phase shift-keying communication using phase difference modulation.

Orbital angular momentum (OAM) mode offers a promising modulation dimension for high-order shift-keying (SK) communication due to its mode orthogonality. However, the expansion of modulation order through superposing OAM modes is constrained by the mode-field mismatch resulting from the rapidly increased divergence with mode orders. Herein, we address this problem by propose a phase-difference modulation strategy that breaks the limitation of modulation orders via introducing a phase-difference degree of freedom (DoF) beyond OAM modes. Phase-difference modulation exploits the sensitivity of mode interference to phase differences, thereby providing distinct tunable parameters. This enables the generation of a series of codable spatial modes with continuous variation within the same superposed OAM modes by manipulating the interference state. Due to the inherent independence between OAM mode and phase-difference DoF, the number of codable modes increases exponentially, which facilitates establishing ultra-high-order phase shift-keying by discretizing the continuous phase difference and establishing a one-to-one mapping between coding symbols and constructed modes. We show that a phase shift-keying communication link with a modulation order of up to 4 × 104 is achieved by employing only 3 OAM modes (+1, + 2 and +3), and the decode accuracy reaches 99.9%. Since the modulation order is exponentially correlated with the OAM modes and phase differences, the order can be greatly improved by further increasing the superimposed OAM modes, which may provide new insight for high-order OAM-based SK communication.

Rigorous higher-order Poincaré optical vortex modes

The state of polarization of a general form of an optical vortex mode is represented by the vector ϵ^ m , which is associated with a vector light mode of order m>0. It is formed as a linear combination of two product terms involving the phase functions e±imϕ times the optical spin unit vectors σ∓. Any such state of polarization corresponds to a unique point (Θ P ,Φ P ) on the surface of the order m unit Poincaré sphere. However, albeit a key property, the general form of the vector potential in the Lorenz gauge A=ϵ^ m Ψ m , from which the fields are derived, including the longitudinal fields, has neither been considered nor has had its consequences been explored. Here, we show that the spatial dependence of Ψ m can be found by rigorously demanding that the product ϵ^ m Ψ m satisfies the vector paraxial equation. For a given order m this leads to a unique Ψ m , which has no azimuthal phase of the kind e i ℓ ϕ , and it is a solution of a scalar partial differential equation with ρ and z as the only variables. The theory is employed to evaluate the angular momentum for a general Poincaré mode of order m yielding the angular momentum for right- and left- circularly polarized, elliptically polarized, linearly polarized and radially and azimuthally polarized higher-order modes. We find that in applications involving Laguerre–Gaussian modes, only the modes of order m≥2 have non-zero angular momentum. All modes have zero angular momentum for points on the equatorial circle for which cos⁡Θ P =0.

Strain/displacement field reconstruction and load identification of bracket arm structure of high-speed maglev train based on superposition conversion algorithm

The bracket arm structure, subjected to long-term vertical levitation and transversal guidance forces, is a key load-bearing component of high-speed maglev trains. It is crucial to monitor strain, displacement, and load in real time to evaluate structural health. However, it is almost impossible to measure directly at the service site of trains due to the intricacy of the bracket arm structure and the constrained installation area. Hence, it is an effective and feasible approach to reconstruct the strain/displacement field using a limited amount of strain information from FBG sensors. In order to reconstruct the strain/displacement field and identify the load on complicated structures, a load–strain/displacement superposition conversion algorithm is proposed in this paper. The modal coordinate and the mode-shape matrix are swapped out for the load weight and the load–strain/displacement matrix, respectively. Thus, it gets around the difficulty of choosing the mode order in traditional modal theory. In addition, the algorithm can achieve full-field reconstruction of both strain and displacement by measuring only part of the nodal strain response, reducing the redundancy of the traditional algorithm. Finally, numerical simulations and experimental tests were carried out to verify the feasibility of the proposed method for field reconstruction and load identification.

Neural network model identification control of dual-inertia system with a flexible load considering payload mass variation and nonlinear deformation

The dual-inertia system with a flexible load (DSFL) is a complex nonlinear model, which originates from the flexible load deformation and payload mass variation. In dynamic modeling, it is impossible to consider all the nonlinear factors, including high-order modes and inaccurate friction torque, which leads to the existence of uncertain components in the DSFL. Based on this, it is impossible to build a dynamic model of the DSFL that is completely consistent with the real physical model. This modeling errors increases the tracking errors of the DSFL. In this study, the neural networks are employed to recognize the lumped uncertain components of the DSFL dynamic model, so as to reduce the flexible load's tracking error. Firstly, based on the deformation accuracy comparison, a relatively high precision model simplification method is proposed, which neglects the second order mode. Next, the control law of the neural network identification control strategy is designed according to the stability theorem. Finally, through physical control experiments and simulation analysis, it is shown that this control strategy enhances the motion accuracy of the DSFL. The experimental results show that this control strategy predicted by the radial basis function (RBF) neural network can reduce the rotation angle error by 15.86%.

MANAGEMENT OF FUEL CONSUMPTION OF 200 MW POWER UNIT WHEN OPERATING IN FREQUENT START-UP MODE

In the context of insufficient maneuvering capacities in the United Energy System of Ukraine, 200 MW power units are used to cover peak loads in variable operating modes. At the same time, there is a deterioration in the economic performance of power equipment. The efficiency of power generation directly depends on the operating modes of the power unit. Therefore, the task was set to develop a system to rationalize operating modes in order to increase efficiency. The average annual specific fuel consumption was chosen as the objective function. To calculate the specific consumption during the year, the method of bringing all losses during start-up and stationary operation to similar consumption of conventional fuel was used. The following factors were selected as optimization factors: the power unit operation time during the year, the total number of starts from different thermal states for 1 year, and the proportion of starts from different thermal states. The limits of change in the factors were chosen as follows: the number of hours of power unit operation ti from 2000 to 6500 hours per year; annual number of starts ni from 25 to 75 times per year; the share of starts from the cold state of metal CSi from 0.1 to 0.9; the share of starts from the hot state GSj within the share of all starts (hot and un-cooled) from 0 to 1 The developed mathematical model allows to estimate fuel consumption for all possible combinations of operational factors. To demonstrate the operation of this system, calculations were performed for a specific 200 MW power unit with a TP-100 power boiler and a K-200-130 steam turbine. The main parameters of the power unit operation mode were determined using the start-up map and the operating instructions developed by the manufacturer. The calculations established a rational distribution of operating parameters, at which the consumption of conditional fuel is 334-340 g.c.f./kWh. It has been established that the rational number of hours of power unit operation is ti = 5500-6500 h/year, with the annual number of starts ni = 25-36 year-1, while the share of starts should be: from the cold state of the metal CSi = 0.72-0.9; from the hot state HSj = 0.1-0.28; from the un-cooled state USi,j = 0-0.18, and then the difference between the most rational and irrational operating modes is 16.5 % (fuel consumption of 55 g.c.f /kWh).

Processing of research results to restore and maintain the fountain pumping mode in order to ensure that the wells work in optimal modes

Various computer programs have been developed for gas lift wells. Existing programs have certain advantages as well as disadvantages. These shortcomings are due to the large number of parameters included in the program, difficulties in ensuring the operation of wells in the interval between optimal and maximum modes in mining conditions, while it is possible to use them in wells, but their application in wells operating with the fountain-gaslift operation method is not intended. Current programs do not allow to group wells and determine the optimal modes of other wells included in the group as a result of processing the three-mode data of one well. For this reason, there is a need to develop it. Compared to other programs in mining conditions, the new computer program, which is easier to use and the accuracy of the obtained results is higher, allows the wells working with the fountain-gaslift and gaslift method to be operated in the interval between the optimal mode and the maximum mode based on the processing of research materials in three modes. With the help of this program, it is possible to calculate the optimal and maximum modes for fountain-gas lift and gas lift wells, graphically describe the results of equal processing in new coordinates and group the wells.

Effects of Topside Ionosphere Modeling Parameters on Differential Code Bias (DCB) Estimation Using LEO Satellite Observations

Given the potential of low-earth orbit (LEO) satellites in terms of navigation enhancement, accurately estimating the differential code bias (DCB) of GNSS satellites and LEO satellites is an important research topic. In this study, to obtain accurate DCB estimates, the effects of vertical total electron content (VTEC) modeling parameters of the topside ionosphere on DCB estimation were investigated using LEO observations for the first time. Different modeling parameters were set in the DCB estimations, encompassing modeling spacing in the dynamic temporal mode and degree and order (D&O) in spherical harmonic modeling. The DCB precisions were then evaluated, and the impacts were analyzed. Thus, a number of crucial and beneficial conclusions are drawn: (1) The maximum differences in the GPS DCB estimates after adopting different modeling spacings and different D&Os exhibit that the different modeling spacings or D&Os both affect the GPS DCB estimates and their root-mean square (RMS), and the effects of the two are at the same level. (2) The maximum differences in receiver DCBs using different modeling spacings indicate that the modeling spacing has a significant impact on the receiver DCBs, compared with GPS DCBs. Whereas, the maximum differences in receiver DCBs with different modeling D&Os are inferior to the differences in the GPS DCBs. That is, the modeling spacing has a greater impact on the LEO DCBs than those of the modeling D&O. (3) The experimental results indicate that the GPS DCB estimates using a modeling spacing of 12H have higher precisions than the others, whereas LEO receiver DCBs using a spacing of 4H or 6H obtain optimal STD. In terms of modeling D&O, adopting 8D&O in the LEO-based VTEC modeling can attain superior estimates and precisions for both GPS and LEO DCBs. The research conclusions can provide references for LEO-augmented DCB estimation.