Adjustment Coefficient Research Articles

Effects of Transmission Mechanism of Monetary Policy Channels on Economic Growth in Ethiopia: Cointegration and Causality Analysis Approach

The study aimed at investigating and analyzing factors those effects of transmission mechanism of monetary policy channels on economic growth in Ethiopia using a 36 years’ time series data. To this end, variables such as economic growth (dependent variable), and other regress variables such as real lending rate, real effective exchange rate, credit for private sector, consumer price index, trade of opens, gross capital formation, and money supply are considered. An empirical model linking the real GDP to its theoretical effects is then specified. This study had employed the co-integration and vector error correction model (VECM) analysis with impulse response and variance decomposition analysis to provide robust long run effects and short run dynamic effects on the real GDP. All variables under consideration are integrated of order one I (1) and also co-integrated. Vector Error Correction Model/VECM/ results show that real GDP was positively and significantly affected by the real effective exchange rate, money supply, gross capital formation (investment), credit for private sector, trade of openness over a period of long-run; while real leading interest rate and consumer price index (inflation) have significant negative effect. The estimate of the speed of adjustment coefficient found in this study indicates that about a 31 percent of the variation in the real GDP from its equilibrium level is corrected within a year. The study suggests that lowering the lending interest rate can encourage more private investment because it will encourage private investors to borrow more, which will increase investment in Ethiopia. Since investment is one of the factors that determine the gross domestic product, this will result in an increase in the GDP.

Study on seismic failure mechanism and damage model of unconstrained adobe block walls

Through the quasi-static cyclic in-plane loading test of three kinds of unconstrained adobe block walls, namely plain adobe wall, modified mud adobe wall and modified adobe wall, the failure mode and seismic performance of each specimen were clarified. Using residual deformation and cumulative energy dissipation as failure parameters, a two-parameter seismic damage model of unconstrained adobe block walls was established. and a calculation method for the adjustment coefficients of energy consumption items was provided. The results showed that the failure mode of the typical unconstrained adobe block wall under earthquake action was not affected by the modification of adobe materials, and the final failure mode was shear failure along the mud crack and the inclined crack extending through the block. Furthermore, the proposed seismic damage model can well reflect the evolution law of earthquake damage of adobe block walls, and the recommended damage index boundary values for five performance levels were given, providing a reference for performance-based seismic design and damage assessment of adobe block walls.

МОДЕЛЮВАННЯ АСИНХРОННИХ МАШИН У СКЛАДІ ЕЛЕКТРОМЕХАНІЧНИХ СИСТЕМ З УРАХУВАННЯМ ВТРАТ У СТАЛІ СТАТОРА

A comparative study has been conducted on methods for accounting for the influence of losses in the stator iron of squirrel-cage induction motors on the operating parameters. A comparison was made between reference data and calculation results of the nominal mode parameters of an asynchronous motor without considering losses in the stator iron and with their consideration using equivalent resistances connected in parallel to the motor, as well as equivalent circuits of losses in the stator. The effect of the ratio of active and inductive components of the load of equivalent stator loss circuits on the results of mathematical modeling has been investigated. The study was carried out based on a universal mathematical model of an asynchronous motor of electromechanical systems with an arbitrary stator winding scheme. An algorithm for determining and adjusting the parameters of the stator loss circuits during the integration of the differential equations of electrical and mechanical balance of the asynchronous motor to a steady-state value has been developed, based on the values of losses in the stator iron (depending on the induction and frequency) and the effective value of the current of the equivalent circuit. To ensure solution stability, the use of an iteration coefficient and discretization of resistance adjustment has been justified. The application of stator iron loss circuits in the mathematical model of an asynchronous machine in generator mode has been justified, when the use of parallel connected equivalent resistances contradicts the machine's energy diagram. References 10, figure 1, table 1.

Multi-objective robust dynamic pricing and operation strategy optimization for integrated energy system based on stackelberg game

The integrated energy system (IES) with hydrogen storage has become one of the most important developments in multi-energy coupling field, where the severe conflict of interests between different entities leads to great challenges to the economy and low-carbon operation. A multi-objective robust dynamic pricing and operation strategy optimization method based on the Stackelberg game is proposed for the hydrogen-containing energy storage (HES) IES. Firstly, the HES-IES trading framework is established based on the introduction of an integrated energy operator (IEO) and a load aggregator (LA). Secondly, a multi-objective robust Stackelberg game model is developed with the IEO as the leader and the LA as the follower, considering the minimization of operating costs and carbon emissions of the IEO and the minimization of integrated energy costs of the LA as the objectives. Finally, the compromise planning and the max-min fuzzy are addressed to solve the multi-objective model, which adopts the adaptive differential evolution (ADE) algorithm. In addition, the robust optimization (RO) with adjustable coefficients is employed to tackle uncertainties of source and load. The results show that this method can effectively balance the operating costs and carbon emissions of the system, improve the benefit of the IEO, reduce the costs of the LA, and avoid the uncertainty risk. Compared with traditional algorithms, the ADE algorithm has significant advantages in the number of iterations and solving time. In summary, the multi-objective robust dynamic pricing and operation strategy optimization proposed in this paper could effectively achieve the benefit balance between the IEO and the LA, also further improve the economy and robustness of the system and reduce carbon emissions.

Intelligent spare ordering and replacement optimisation leveraging adaptive prediction information

Predicting system health using inspection technologies is crucial for efficiently managing the maintenance of various industrial products. This study introduced an innovative policy for intelligently ordering and replacing spare parts. It utilises real-time prediction data to make sequential decisions on whether to schedule spares and when to conduct non-immediate maintenance. A generalised non-linear stochastic process was established to capture the underlying degradation path, with a lifetime coefficient updated through Bayesian inference. Conditional reliability assessed during regular inspections determines when spare preparations and delayed replacements are warranted. Predictive replacements can also be postponed based on the expected remaining lifetime adjusted for safety factors and spare lead times. The model dynamically optimises operational costs by iteratively optimising spare-ordering times, postponement intervals, and adjustment coefficients. Numerical experiments on high-speed train gearboxes validated its superior cost-effectiveness compared to conventional approaches.

Research on English Teaching of Solar Energy and Photovoltaic Power Generation Technology

As an emerging energy development industry, solar-photovoltaic power generation technology has the problems of inaccurate translation and translation bias, which affects its long-term development. Therefore, improving the English teaching level of solar-photovoltaic power generation technology majors is an urgent problem to be solved. In order to explore the relationship between solar-photovoltaic power generation technology and the professional practice of English teaching, this paper establishes a vocabulary set of English teaching based on the Clicker calculation model to match the needs of solar-photovoltaic power generation technology majors. Then, combined with teaching theory and intelligent algorithm, the translation constraint feature was used to call and extract data, so as to verify the matching accuracy of solar-photovoltaic power generation technology and English teaching practice. The results show that the matching adjustment coefficients t=-2.822 and df=0.23, and the professional adjustment coefficients t=-3.011 and df=0.85 in the proposed model have significant changes, which are significantly better than those of the manual algorithm. Moreover, the matching accuracy of the Clicker calculation model is more than 95%. The results show that there is a positive correlation between solar-photovoltaic power generation technology and English teaching practice, and the Clicker calculation model can provide support for the matching of solar-photovoltaic power generation technology and English teaching practice.

A broadband active sound absorber with adjustable absorption coefficient and bandwidth.

Broadband adjustable sound absorbers are desired for controlling the acoustic conditions within enclosed spaces. Existing studies on acoustic absorbers, either passive or active, aim to maximize the sound absorption coefficients over an extended frequency band. By contrast, this paper introduces a tunable acoustic absorber, whose working frequency band and sound absorption characteristics can be defined by users for different applications. The approach leverages an error signal that can be synthesized using a standing wave separation technique. The error signal encodes different target reflection coefficients, leading to arbitrary absorption coefficients between 0 and 1. Experimental validation is conducted in a one-dimensional standing wave tube, demonstrating that the proposed active absorber achieves near-perfect absorption within the 150-1600 Hz frequency range, boasting an average absorption coefficient of 0.98. Adjustable absorption is demonstrated across three octave bands, aligning closely with theoretical predictions. Furthermore, when coupled with a shaping filter, the absorber exhibits spectrally tunable broadband absorption capabilities, selectively reflecting specific frequency bands while effectively absorbing others. These outcomes underscore the versatile tunability of the proposed active acoustic absorber, which is expected to pave the way for personalized regulating of the indoor acoustic environment.

Increased trial-to-trial similarity and reduced temporal overlap of muscle synergy activation coefficients manifest during learning and with increasing movement proficiency

Muscle synergy analyses are used to enhance our understanding of motor control. Spatially fixed synergy weights coordinate multiple co-active muscles through activation commands, known as activation coefficients. To gain a more comprehensive understanding of motor learning, it is essential to understand how activation coefficients vary during a learning task and at different levels of movement proficiency. Participants walked on a line, a beam, and learned to walk on a tightrope—tasks that represent different levels of proficiency. Muscle synergies were extracted from electromyography signals across all conditions and the number of synergies was determined by the knee-point of the total variance accounted for (tVAF) curve. The results indicated that the tVAF of one synergy decreased with task proficiency, with the tightrope task resulting in the highest tVAF compared to the line and beam tasks. Furthermore, with increasing proficiency and after a learning process, trial-to-trial similarity increased and temporal overlap of synergy activation coefficients decreased. Consequently, we propose that precise adjustment and refinement of synergy activation coefficients play a pivotal role in motor learning.

Coordination of interests between upstream and downstream governments in water source areas

Exploration of establishing a robust intergovernmental benefit compensation mechanism for water source areas holds significant importance in promoting regional coordinated development. Taking the Guanting Reservoir basin, a water source area in Beijing, China, as an example, we established an ecological location model with urban water sources as the core by drawing on the concept of spatial circle structure in traditional location theory. Based on this, we proposed the theory of ecological cost of water source land level difference and analyzed the basic composition of ecological cost of water source land. Finally, the differential ecological costs method was used to estimate the ideal horizontal eco-compensation funds between the downstream city of the water source (Beijing) and the upstream city (Zhangjiakou). The results are as follows: (1) the closer to the water source reservoir area and the higher the protection zone level, the greater the contribution of the ecological product value realization and the ecological protection costs to the protection of water resources in the reservoir area. (2) The compensation funds for water source areas are jointly composed of the increment of ecological product value and protection costs. (3) In 2021, the value addition of ecological products in the upstream region was 3.075 billion yuan, and the protection cost was 6.702 billion yuan. After multiplying by the differential adjustment coefficient, the horizontal eco-compensation amount that the upstream cities should receive in 2021 is 4.194 billion yuan. This study theoretically addresses the shortcomings of traditional ecological compensation, which overlooked differences in resource and environmental costs due to variations in ecological functional location. It provides a new perspective for further exploring the role of location theory in addressing inter-governmental interest coordination issues in cross-border water source areas.

The Effects of Axis-flip of the Refractive Cylinder on vision and patient reported outcome measures following Toric Intraocular Lens implantation.

To investigate the effects of cylinder axis-flip following toric intraocular lens (TIOL) implantation on vision and patient reported outcome measures (PROMs). Teaching hospital in the United Kingdom. Post-hoc analysis of data from patients who participated in a prospective randomised study of TIOLs. Axis-flip was defined as a change in post-operative refractive cylinder axis of 900 +/- 22.50 from the pre-operative biometric axis. Uncorrected distance visual acuity (UDVA), best-corrected distance visual acuity (BDVA), residual refractive cylinder (RC), and CATPROM-5 and EQ5D3L quality of life (QOL) scores were analysed. At 6 months, axis flip occurred in 29 (34.5%) of 84 eyes, of which 28 had with-the-rule astigmatism (WTR) pre-operatively. Mean (+/-standard deviation) UDVA (logMAR) was 0.13 (0.16) in flipped cases (FC) and 0.10 (0.14) in un-flipped cases (UF) (p=0.88). BDVA was 0.01 (0.11) in FC and was 0.00 (0.09) in UF (p=0.68). Mean RC was 0.74 dioptres (D) (0.41) in FC and 0.93D (0.47) in UF (p=0.08). Mean CATPROM-5 score was -6.22.98 (2.56) in FC and -5.52 (3.03) in UF (p=0.29). Mean EQ5D3L calibrated score was 0.89 (0.19) in FC and 0.85 (0.19) in UF (p=0.35). Retrospectively applying coefficients of adjustment to account for posterior corneal astigmatism (PCA), suggested that 6 eyes (21%) of FC with WTR might have avoided axis-flip. Axis flipping following TIOL implantation did not adversely influence visual acuity or PROMs scores. Most FC had WTR pre-operatively. Adjusting for PCA might have reduced axis flip in some of these eyes.

Multi-objective optimization design of rail grinding profile in Curve Section of Subway based on wear Evolution and representative worn profile

Curve rail grinding has always been one of the key points of subway maintenance and repair. The appropriate grinding can effectively reduce wear. A multi-objective optimization design method for grinding profiles in curved sections is proposed. Firstly, representative grinding profiles are selected as the initial population using the dynamic time regularization algorithm (DTW). Then, the optimal design range is determined based on wear characterization analysis, and mathematical expressions of wheel profiles are chosen as design variables to establish a parametric model. Next, the prediction model considering the evolution of wheel wear is incorporated into the multi-objective function, and objective function adaptive weight adjustment coefficient factors are introduced to establish the multi-objective optimization model for wheel profiles. The Latin hypercubic sampling method is employed to establish the RBF agent model for simulation calculation, and the optimization design of wheel profiles is carried out using the TS-NSGA-II multi-objective algorithm.

Benchmarking the Performance of the Actuator-Disk Method for Low-Pressure Axial Flow Fan Simulation

Abstract The actuator-disk method is a cost-effective simulation tool that implicitly represents the rotor of a turbomachine using a blade-element approach combined with two-dimensional (2D) airfoil coefficient input data. Actuator-disk models further rely upon empirical coefficient corrections to modify the 2D input data to better mimic physical blade aerodynamic characteristics. However, the fabrication of high-fidelity, general-purpose corrections remains a formidable challenge, so the limits of actuator-disk model accuracy have never been rigorously tested and remain uncertain. This is especially the case for low-pressure axial flow fan models, given the relative lack of empirical corrections conceived specifically for fan rotor simulation. In this study, benchmark performance limits of the actuator-disk method for axial flow fan analysis are explored. The limits of the modeling approach are interrogated by simulating actuator-disk fan models embedded with accurate physical blade data derived from explicit three-dimensional (3D) fan model computations. It is subsequently shown that even with a near-precise coefficient description, the method remains unreliable. However, using an unconventional actuator-disk model formulation that is based directly on 3D blade force inputs, it is demonstrated that the accuracy of conventional models can be noticeably enhanced if the input coefficient data is artificially manipulated. This nonphysical tuning of the input coefficient data is required to compensate for the simplified flow fields produced by the reduced-order modeling approach. The needed coefficient adjustments, referred to as modeling corrections, are subsequently defined and explained alongside the presentation of new realistic performance targets for future actuator-disk fan model variants.

Power Allocation Scheme for Multi-Static Radar to Stably Track Self-Defense Jammers

Due to suppression jamming by jammers, the signal-to-interference-plus-noise ratio (SINR) during tracking tasks is significantly reduced, thereby decreasing the target detection probability of radar systems. This may result in the interruption of the target track. To address this issue, we propose a multi-static radar power allocation algorithm that enhances the detection and tracking performance of multiple radars in relation to their targets by optimizing power resource allocation. Initially, the echo signal model and measurement model of multi-static radar are formulated, followed by the derivation of the Bayesian Cramér–Rao lower bound (BCRLB). The multi-objective optimization method is utilized to establish the objective function for joint tracking and detection, with dynamic adjustment of the weight coefficient to balance the tracking and detection performance of multiple radars. This ensures the reliability and anti-jamming capability of the multi-static radar system. Simulation results indicate that the proposed algorithm can prevent the interruption of jammer tracking and maintain robust tracking performance.

Study on bending fatigue performance of recycled aggregate backfill subgrade

Recycled aggregate (RA), as a backfill subgrade material, has strong reproducibility and environmental protection, which cannot only effectively reduce resource consumption and environmental pollution but also achieve recycling of resources. Therefore, a study on the bending fatigue performance of RA backfill subgrade is proposed. Based on linear elastic state, softening state, and damage accumulation state, the variation law of bending fatigue damage variables is analyzed, and the stiffness of RA under cyclic load is calculated. According to the correlation between fatigue damage corresponding to two different load links and the constitutive relationship of RA, the identification results of bending fatigue damage state based on RA backfilling subgrade is obtained. The advantages of the fatigue damage model of RA are analyzed, and the fatigue life equation is established based on the damage evolution equation. Strain, stiffness modulus, asphalt saturation, and asphalt mixture adjustment coefficient are selected as model parameters to establish the fatigue damage model of RA. The flexural bearing capacity of the double-reinforced rectangular section is calculated, and the flexural fatigue performance of RA backfill subgrade is analyzed. The test results show that the high stress level in this method leads to a sharp decline in the fatigue life of the specimen, and the influence of fatigue damage gradually appears, which is helpful to improve the durability and safety of the subgrade structure. The range of change shows a small range, which is close to the reduction coefficient result, indicating that this method has high reliability in analyzing the bending fatigue performance of RA backfill subgrade.

Refractive outcomes after V4c Toric collamer lens implantation over 1y of follow-up.

To evaluate refractive outcomes and corneal astigmatism changes after Toric implantable collamer lens with a central port (V4c T-ICL) implantation over 1y of follow-up. A retrospective study was performed including 50 eyes of 50 patients that underwent V4c T-ICL implantation. Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, refractive and corneal astigmatism changes and corneal coupling correction were evaluated preoperatively, 1 and 12mo postoperatively. Vector analysis was used for astigmatism changes. Coefficient of adjustment (CAdj) was calculated for corneal coupling analysis. The mean UDVA achieved was 0.03 logMAR at 1mo and remained unchanged throughout the whole follow-up (P=0.193). At the last visit, 84% of the eyes achieved a CDVA of 0.00 logMAR or better. Regarding spherical equivalent refraction (SEQ), 96% of eyes were ranges of ±1.00 D and 84% of them within ±0.50 D. Also, 94% of eyes had a remaining refractive cylinder within ±1.00 D and 78% of them within ±0.50 D. Both, SEQ and refractive cylinder, remain stable over the postoperative follow-up (P=1.000 and P=0.660, respectively). In terms of surgically induced astigmatism (SIA), no statistically significant differences were found over the follow-up (P=0.102) and under correction was found with a correction index lower than the unit at each visit. A keratometric astigmatism induced of 0.59±0.53 (vector mean: 0.26×73°) D was reached at the last visit. No significant changes in terms of corneal astigmatism orientation were reported over post-surgery visits (P=0.129 and P=0.097 at 1 and 12mo respectively). No clinical significance was found for CAdj on with-the-rule astigmatism. No postoperative complications resulting from the surgery were found. Refractive outcomes suggest that the V4c T-ICL implantation for correction of myopic astigmatism was satisfactory in terms of effectiveness, safety, and stability during 1y of follow-up. Corneal astigmatism induced by the incision around 0.5 D is achieved according to the remaining refractive cylinder found at one-year post-surgery. Corneal coupling analysis results in no unexpected spherical change.

Two-stage group decision making methodology with hesitant fuzzy preference relations under social network: Multiplicative consistency determination and personalized feedback

Some social network group decision making (SNGDM) researches may overlook two issues: (1) the impact of consistency on decision reliability and decision makers’ (DMs’) status in social network, and (2) DMs’ personalization during consensus reaching process. In response to these two issues, a two-stage SNGDM model is proposed for hesitant fuzzy preference relations (HFPRs). In the first stage, multiplicative consistency determination and improvement of HFPRs are achieved. For complete and incomplete HFPRs, several programming models are constructed to classify consistency types. When it comes to inconsistent HFPRs, an inconsistency fixing method is designed to ensure the original HFPRs as much as possible. With the improvement of DMs’ consistency, their status in social network will be dynamically enhanced. In the second stage, two programming models are devised to elicit the reasonable individual priority weight vector in consistent HFPR. Further, minimum adjustment cost-based personalized feedback mechanism is invented to attain the optimal personalized adjustment coefficient and recommendation, and achieve the harmonious unity of individual personalization and group consensus. Finally, the superiority of our proposal is verified by comparative analysis and illustrative example.

Research on dynamic game operation behavior of multi‐oligopoly car‐sharing operators considering off‐peak pricing factors

AbstractIn the practical evolution of shared vehicle systems, numerous societal factors come into play, such as inadequate parking infrastructure, battery capacity, and the budget for technological improvement. This study integrates the operational realities of shared vehicle systems with governmental carbon emission reduction policies and “double control” initiatives. Considering various perturbations, the paper constructs a Stackelberg short‐term model among diverse oligopolistic shared vehicle operators with technique sharing. It also develops a long‐term repeated game framework to scrutinize the impact of pertinent parameters on operators' decision variables and profits, along with system stability and complexity. The findings, elucidated through numerical analyses, reveal that the burgeoning sensitivity of users to energy conservation augments the overall shared vehicle market. The technique sharing mechanism boosts the benefit of the whole group of shared vehicle operators while diminishing the start‐up operators' revenue. In the long term, however, excessive price adjustments by SEV operators may lead to market chaos and profit erosion. Conversely, enhancing the adjustment coefficient of technological level levels by start‐up SEV2 operators may result solely in their own decision‐making becoming unmanageable. Finally, we found that both the methods of external force feedback control and parameter control are effective in restoring the chaotic market to stability.

Research on Photovoltaic Maximum Power Point Tracking Control Based on Improved Tuna Swarm Algorithm and Adaptive Perturbation Observation Method

In situations where photovoltaic (PV) systems are exposed to varying light intensities, the conventional maximum power point tracking (MPPT) control algorithm may become trapped in a local optimal state. In order to address this issue, a two-step MPPT control strategy is suggested utilizing an improved tuna swarm optimization (ITSO) algorithm along with an adaptive perturbation and observation (AP&O) technique. For the sake of enhancing population diversity, the ITSO algorithm is initialized by the SPM chaos mapping population. In addition, it also uses the parameters of the spiral feeding strategy of nonlinear processing and the Levy flight strategy adjustment of the weight coefficient to enhance global search ability. In the two-stage MPPT algorithm, the ITSO is applied first to track the vicinity of the global maximum power point (MPP), and then it switches to the AP&O method. The AP&O method’s exceptional local search capability enables the global MPP to be tracked with remarkable speed and precision. To confirm the effectiveness of the suggested algorithm, it is evaluated against fuzzy logic control (FLC), standard tuna swarm optimization (TSO), grey wolf optimization (GWO), particle swarm optimization (PSO), and AP&O. Finally, the proposed MPPT strategy is verified by the MATLAB R2022b and RT-LAB experimental platform. The findings indicate that the suggested method exhibits improved precision and velocity in tracking, efficiently following the global MPP under different shading conditions.

Adaptive inertia control strategy of asynchronous sending system based on coordination between DFIG and HVDC frequency limit controller

In a highly proportional hydropower asynchronous sending grid, the system is in a low damping state at all times because of the dual influence of the highly proportional hydropower water hammer effect and highly proportional DC outgoing rigid load, making frequency stability control difficult. In this study, an adaptive inertia control strategy for an asynchronous sending system based on the coordination of the wind turbine and high-voltage direct current (HVDC) frequency limiter controller (FLC) is proposed for a highly proportional hydropower asynchronous sending grid with a double-fed induction generator as the research object. The wind turbine and HVDC system provide virtual inertia support inside and outside the dead zone of FLC, respectively, and the additional virtual inertia-controlled FLC provides a fast response to the instantaneous power dip caused by wind turbine speed recovery. In addition, fuzzy control is introduced in the inertia control link of the wind turbine and FLC to dynamically adjust the virtual inertia adjustment coefficients of the wind turbine and HVDC system in accordance with the system frequency state to further enhance the coordination of frequency control. The effectiveness of the strategy is verified in a three-machine, single-return, DC outgoing system model.

Dual arrowhead-shaped re-entrant auxetic hybrid metamaterial with adjustable thermal expansion

The lightweight metamaterial with the adjustable coefficient of thermal expansion (CTE) and Poisson's ratio (PR) has aroused great interest in potential engineering applications. However, the bifunctional metamaterials with dual negative properties exhibit relatively narrow ranges of CTE and PR, only considering one direction. In this work, a dual arrowhead-shaped re-entrant auxetic (DARA) hybrid metamaterial with controllable CTE is designed by combining a star-shaped re-entrant structure and a dual arrowhead inclined triangle structure. A theoretical model of the DARA unit cell is established to obtain CTE and PR solutions using the stiffness matrix method, which is verified by the finite element method (FEM). The theoretical model is used to further study the effect of geometric parameters, configuration, and base material on the thermal and mechanical properties. The DARA metamaterial can simultaneously realize the adjustable CTE and PR, especially a wide range of CTE under two directions, from negative to positive values. Furthermore, the 3D-printed DARA samples are fabricated to validate the CTE and PR values of the unit cell, which are in line with the FEM and theoretical values. The bi-metamaterial unit cell exhibits positive, quasi-zero, or negative CTE and PR owing to the synergistic effect of re-entrant and dual arrowhead structure. The deformation mechanism is proposed based on the structure's stretch-bending coupling and stretch-dominated design.