Journal of Engineering Research最新文献_第10页

Design, analysis and development of a proton exchange membrane in fuel cell 燃料电池质子交换膜的设计、分析与研制

IF 2.2 4区工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY

Journal of Engineering Research

Pub Date : 2025-09-01 DOI: 10.1016/j.jer.2024.07.019

Yasir Al-okbi , Muhsin Jaber Jweeg , Mohammed A. Atiya , Rana Al-Dujele

This research presents the design and fabrication of a Proton Exchange Membrane fuel cell (PEMFC) utilising open pore cellular metal foam as the material for the flow plate. Efficient housing designs are suggested for both the hydrogen and oxygen sides, achieved by implementing. The study identifies the flow regime via the open pore cellular metal foam flow plate using Computational Fluid Dynamic (CFD) modelling and analysis techniques. Energy, environmental and economic analyzes (4E) and multi-objective optimization of a PEM fuel cell equipped with coolant channels Energy analysis of a proton exchange membrane fuel cell (PEMFC) with an open-ended anode using agglomerate model: A CFD study A transient heat and mass transfer CFD simulation for proton exchange membrane fuel cells (PEMFC) with a dead-ended anode channel. This research can provide appropriate references and recommendations for future Proton Exchange Membrane Fuel Cell (PEMFC) flow channel designs. The performance improvements of flow channel designs become significant at elevated current density, and with the output voltage increasing to 25.8 %. The estimated performance power of the fuel cell was 6 W, meaning that it was unlikely that the 10 W target would be achieved. In reality, the designs proved to have an excellent open circuit voltage of over 0.9 V, however, the maximum current achieved was below the target, and thus limiting the power to only about 2.1 Watts. The purpose of this paper is to give a general theoretical guidance for current and future relevant R&D activities aiming at high-performance, durable, and low-cost fuel cells as well as a thorough overview of the issues, advancements, and perspectives of the flow-field designs for bipolar plates in PEMFC.

本研究介绍了一种利用多孔金属泡沫作为流板材料的质子交换膜燃料电池（PEMFC）的设计和制造。有效的住房设计建议为氢和氧双方，实现通过实施。该研究利用计算流体动力学（CFD）建模和分析技术确定了开孔多孔金属泡沫流板的流动状态。基于团簇模型的开放式阳极质子交换膜燃料电池（PEMFC）能量分析：CFD研究具有死角阳极通道的质子交换膜燃料电池（PEMFC）的瞬态传热传质CFD模拟。本研究可为未来质子交换膜燃料电池（PEMFC）的流道设计提供参考和建议。当电流密度增大，输出电压增加到25.8 %时，流道设计的性能得到显著改善。燃料电池的估计性能功率为6 W，这意味着不太可能实现10 W的目标。在现实中，该设计被证明具有超过0.9 V的优秀开路电压，然而，实现的最大电流低于目标，从而将功率限制在仅约2.1瓦。本文的目的是为当前和未来的相关研发活动提供一般的理论指导，旨在实现高性能、耐用和低成本的燃料电池，并对PEMFC双极板流场设计的问题、进展和前景进行全面概述。

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引用次数: 0

Human-centered design in the development of innovative technology for the food processing medium, small and micro enterprises (MSMEs) in Uganda 以人为本的设计在乌干达食品加工中小微企业（MSMEs）创新技术开发中的应用

IF 2.2 4区工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY

Journal of Engineering Research

Pub Date : 2025-09-01 DOI: 10.1016/j.jer.2024.05.034

Julia Kigozi , Moses Kalyango , Emmanuel Baidhe , Isaac Oluk , Amy Jamison , Timothy Silberg , Sharon Nalumaga

Taking account of end-user perspectives is crucial in the design and development process to ensure successful technology adoption considering the evolving customer demands. This study utilized the user-centric Human Center Design (HCD) framework to re-develop food processing equipment, specifically pulpers and pasteurizers, previously developed by the Department of Agricultural and Biosystems Engineering (DABE) of Makerere University. The study implemented several interventions to augment the adoption of processing equipment among MSME agro-processors in Uganda. This included development of modified pasteurizers (biomass and electrical) and pulpers, development of user manuals, and training of processors on the use of equipment. All interventions were designed with a focus on the needs and preferences of the end users. This study demonstrates how HCD can be used to develop food processing equipment that addresses the dynamic needs of micro, small, and medium-scale agro-processors in form of production capacity and cost of ownership. The study findings can influence large-scale research and policy toward the production and adoption of user-centric food processing equipment, which in turn can provide agro-processors with increased livelihoods and reduce the major challenge of post-harvest losses.

考虑最终用户的观点在设计和开发过程中是至关重要的，以确保成功地采用考虑到不断变化的客户需求的技术。本研究利用以用户为中心的人类中心设计（HCD）框架重新开发食品加工设备，特别是纸浆机和巴氏杀菌机，之前由马凯雷雷大学农业和生物系统工程系（DABE）开发。该研究实施了若干干预措施，以扩大乌干达中小微企业农业加工商对加工设备的采用。这包括开发改良巴氏杀菌机（生物质和电力）和制浆机，编写用户手册，以及培训加工者如何使用设备。所有干预措施的设计都以最终用户的需求和偏好为重点。本研究展示了如何利用HCD开发食品加工设备，以满足微型、小型和中型农业加工商在生产能力和拥有成本方面的动态需求。研究结果可以影响大规模的研究和政策，以生产和采用以用户为中心的食品加工设备，这反过来又可以为农业加工商提供更多的生计，减少收获后损失的重大挑战。

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引用次数: 0

Sensitivity of the endwall flow in a linear vane cascade to blade fillet geometry 线性叶片叶栅端壁流动对叶片圆角几何形状的敏感性

IF 2.2 4区工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY

Journal of Engineering Research

Pub Date : 2025-09-01 DOI: 10.1016/j.jer.2024.06.009

Adeola S. Shote , Gazi I. Mahmood

Based on the blade chord and inlet velocity, the current computational study uses a linear vane cascade with a large filleted blade-endwall junction with a 2.01 x 10⁵ Reynolds number. Three fillets with related profiles are explored. To evaluate the upshots of geometric differences in a fillet attached to the endwall flow-field, the height and endwall-width of the fillets are changed. The RANS k-ω turbulent model is used in the computations, and the results are compared to experimental results from a similar cascade without the fillet. The computed results of the secondary flow-field in the endwall region along the cascade are compared for baseline (no fillet) and filleted passages. As a result of diminished leading-edge and passage vortices, the fillets lower pitchwise pressure gradients, flow separation, axial vorticity, and overall pressure losses when compared to the baseline. The pros of fillets on endwall secondary flows are however unaffected by fillet's geometric changes.

基于叶片弦线和进口速度，目前的计算研究使用了一个线性叶片叶栅，具有大圆角叶片-端壁连接处，雷诺数为2.01 x 105。探索了具有相关剖面的三个圆角。为了评估连接到端壁流场的圆角的几何差异的结果，改变了圆角的高度和端壁宽度。计算中采用了RANS k-ω湍流模型，并将计算结果与不带圆角的类似叶栅的实验结果进行了比较。对沿叶栅端壁的二次流场计算结果进行了基线（无圆角）和圆角通道的比较。由于减少了前缘和通道涡，与基线相比，圆角降低了俯向压力梯度、流动分离、轴向涡度和总压力损失。然而，圆角对端壁二次流的优点不受圆角几何变化的影响。

引用次数: 0

Double direct progressive filling algorithm to find the double MMF nurse schedule at a pediatric intensive care unit 双直接递进填充算法寻找双MMF护士时间表在儿科重症监护病房

IF 2.2 4区工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY

Journal of Engineering Research

Pub Date : 2025-09-01 DOI: 10.1016/j.jer.2024.05.015

Hamoud Bin Obaid

In this study, the aim is to achieve max-min fair (MMF) resource allocation and min-max fair (MMF) load distribution for nurse schedules at the pediatric intensive care unit (PICU) at a local Saudi hospital. In this paper, an exact algorithmic approach, namely the double direct progressive-filling algorithm (DDPFA), is proposed to achieve the double MMF solution. This algorithm is composed of two phases where the resources are fairly maximized in the first phase, and the loads are fairly minimized in the second phase. For more illustration, the proposed algorithm output (model 1) is compared with other conventional objective specifically maximizing utilization (model 2), and maximizing the minimum resources and minimizing the maximum loads (model 3). The results of the proposed approach outperform the other tested approaches in terms of bed utilization and fairness.

在本研究中，目的是实现最大-最小公平（MMF）资源分配和最小-最大公平（MMF）负荷分配在当地沙特医院儿科重症监护病房（PICU）护士时间表。本文提出了一种精确的算法方法，即双直接渐进填充算法（DDPFA）来实现双MMF解。该算法分为两个阶段，第一阶段资源相对最大化，第二阶段负载相对最小化。为了更好地说明问题，将本文提出的算法输出（模型1）与其他常规目标（特别是利用率最大化（模型2）、资源最小化和负载最小化（模型3））进行比较。结果表明，该方法在床位利用率和公平性方面优于其他测试方法。

引用次数: 0

Silica extraction from sodium silicate for wollastonite synthesis at low temperatures 从水玻璃中提取二氧化硅用于硅灰石的低温合成

IF 2.2 4区工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY

Journal of Engineering Research

Pub Date : 2025-09-01 DOI: 10.1016/j.jer.2024.06.019

Imane Bekhiekh, Ferhat Bouzerara, Mehieddine Bouatrous, Boudjemaa Ghouil

In this study, ceramic wollastonite was prepared at low temperatures by using amorphous silica and calcium oxide powders. The amorphous silica was extracted from sodium silicate, while calcium oxide (CaO) was obtained through the calcination of calcium carbonate (CaCO₃) particles. The effect of reaction temperature on the formation of wollastonite was systematically investigated. The synthesized powders were analyzed using various characterization techniques, including X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The results indicate that the synthesized silica nanopowders exhibit a notable surface area, with specific surface area (SSA) values reaching 148 m²/g for samples subjected to calcination at 600°C. Furthermore, based on XRD and differential scanning calorimetry (DSC) analyses, it is evident that β-CaSiO₃ forms at approximately 780°C and subsequently undergoes complete transformation into α-CaSiO₃ at 1200°C. Notably, this study underscores that the utilization of amorphous silica expedites wollastonite formation at lower temperatures compared to those reported in existing literature.

在本研究中，以无定形二氧化硅和氧化钙粉为原料，在低温下制备陶瓷硅灰石。从硅酸钠中提取无定形二氧化硅，碳酸钙（CaCO3）颗粒煅烧得到氧化钙（CaO）。系统地研究了反应温度对硅灰石形成的影响。利用x射线衍射（XRD）、差示扫描量热法（DSC）、热重分析（TGA）和扫描电子显微镜（SEM）等表征技术对合成的粉末进行了分析。结果表明，合成的纳米二氧化硅粉体具有显著的比表面积，经600℃煅烧后的样品比表面积（SSA）达到148 m²/g。此外，基于XRD和DSC分析，β-CaSiO3在780°C左右形成，随后在1200°C完全转化为α-CaSiO3。值得注意的是，该研究强调，与现有文献报道的相比，非晶硅的利用加速了硅灰石在较低温度下的形成。

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引用次数: 0

Exploring the impact of compressibility on reconstructed porous materials: A numerical study 探索可压缩性对重建多孔材料的影响：数值研究

IF 2.2 4区工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY

Journal of Engineering Research

Pub Date : 2025-09-01 DOI: 10.1016/j.jer.2024.07.018

Herman Szűcs

This study underscores fluid density's significance in CFD simulations for porous materials, addressing its impact on accuracy and computational efficiency. The paper proposes a tailored form of Navier-Stokes equations that accounts for fluid density's influence on CFD analyses of porous materials in industrial contexts, including cases where the solid phase is deformable. Numerical analyses demonstrate fluid density's significance (

ρ \neq

constant) and explore the importance of the energy equation in governing equations. The energy equation is essential in setting up the governing equations, as it calculates thermal characteristic length based on cell temperatures. By examining various porous material samples, the study suggests a streamlined approach: employing a single coupled CFD-FEM simulation to directly determine each geometrical parameter. Additionally, the study investigates the capability to accurately simulate turbulent fluid motion at the pore scale and analyze the flow field characterization within porous media. Computational cost analyses underscore the advantages of coupled simulations, establishing their profitability over separate parameter-specific simulations.

本研究强调了流体密度在多孔材料CFD模拟中的重要性，解决了其对准确性和计算效率的影响。本文提出了一种定制形式的Navier-Stokes方程，该方程考虑了工业环境中流体密度对多孔材料CFD分析的影响，包括固相可变形的情况。数值分析证明了流体密度的重要性（ρ≠常数），并探讨了能量方程在控制方程中的重要性。能量方程在建立控制方程中是必不可少的，因为它计算基于电池温度的热特性长度。通过检查各种多孔材料样品，研究提出了一种简化的方法：采用单个耦合CFD-FEM模拟来直接确定每个几何参数。此外，该研究还研究了在孔隙尺度上精确模拟湍流运动和分析多孔介质内流场特征的能力。计算成本分析强调了耦合模拟的优势，建立了它们比单独参数特定模拟的盈利能力。

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引用次数: 0

Performance evaluation in die-sinking EDM of polygonal micro cavities over EN-24 alloy steel using cylindrical electrode and polygon cycle approach 使用圆柱形电极和多边形循环方法对 EN-24 合金钢上多边形微腔的电火花成形加工进行性能评估

IF 2.2 4区工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY

Journal of Engineering Research

Pub Date : 2025-09-01 DOI: 10.1016/j.jer.2024.06.006

Shrikant Vidya , Reeta Wattal , P. Venkateswara Rao

The integration of advanced Electrical Discharge Machining (EDM) technology, incorporating short and electronically pulsed discharges with precise circular electrode movements, has enabled the production of intricate 3D microstructures and cavities. This paper aims to investigate the machining performance of polygonal cavities—triangular, square, pentagon, and hexagon—fabricated on steel samples using a 400 µm cylindrical copper electrode within the polygon cycle approach of EDM. Experimental investigations were conducted to assess shape error, tool wear rate, recast layer formation, and elemental characterization. Various discharge patterns and side discharges were examined to understand their effects on spark gap uniformity, tool deflection, and discharge stability. The results revealed non-uniform spark gaps, tool deflection, and corner rounding due to varying discharge patterns and side discharges. Tool wear rate was found to be directly related to polygon complexity, with higher-order polygons leading to increased wear due to extended machining durations and heat accumulation. The maximum tool wear of 7.69 × 10⁴ µm³/s occurred in case of hexagonal cavities while in case of triangular cavities, the tool wear rate was minimum having value of 5.77 × 10⁴ µm³/s. Scanning Electron Microscopy (SEM) examinations showed the presence of recast layers and micro-cracks, particularly in cavities with higher shape complexities. Energy Dispersive X-ray Spectroscopy (EDS) analysis identified copper deposition, local material evaporation, and foreign element accumulation on the cavity surfaces. This study provides insights into the machining performance of polygonal cavities in EDM processes. The findings underscore the influence of discharge patterns, polygon complexity, and material interactions on tool wear, surface quality, and microstructure integrity. Understanding these factors can inform optimization strategies for EDM processes, leading to enhanced precision and efficiency in microstructure fabrication.

先进的电火花加工（EDM）技术的集成，结合短和电子脉冲放电与精确的圆形电极运动，使复杂的3D微结构和腔的生产成为可能。本文旨在研究在电火花加工的多边形循环方法下，使用400 µm圆柱形铜电极在钢样品上制造三角形、正方形、五边形和六边形的多边形腔的加工性能。进行了实验研究，以评估形状误差、刀具磨损率、重铸层形成和元素表征。研究了不同的放电模式和侧面放电，以了解它们对火花间隙均匀性、刀具偏转和放电稳定性的影响。结果显示，由于不同的放电模式和侧面放电，火花间隙不均匀，刀具偏转和圆角。刀具磨损率与多边形复杂度直接相关，高阶多边形由于延长加工时间和热积累而导致磨损增加。六角形空腔的刀具磨损率最大，为7.69 × 104µm3/s，三角形空腔的刀具磨损率最小，为5.77 × 104µm3/s。扫描电镜（SEM）检查显示存在重铸层和微裂纹，特别是在形状复杂的空腔中。能量色散x射线光谱（EDS）分析发现了铜沉积、局部物质蒸发和腔表面的外来元素积累。该研究为电火花加工中多边形腔的加工性能提供了见解。研究结果强调了放电模式、多边形复杂性和材料相互作用对刀具磨损、表面质量和微观结构完整性的影响。了解这些因素可以为电火花加工工艺的优化策略提供信息，从而提高微结构制造的精度和效率。

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引用次数: 0

X-ray pneumonia detection using angular and radial local binary patterns fusion 利用角度和径向局部二元模式融合进行 X 射线肺炎检测

IF 2.2 4区工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY

Journal of Engineering Research

Pub Date : 2025-09-01 DOI: 10.1016/j.jer.2024.06.013

Naser Zaeri , Rabie K. Dib

Detecting pneumonia via X-ray images is a crucial phase in determining any probable bacterial or viral disease. The automation of this stage is critical since it speeds up the diagnosing process. LBPs have excelled in investigating local conditions within a neighborhood, where they aggregate and analyze local statistical results. In this paper, we present a novel family of LBP descriptors based on local accumulative pixel disparities. We construct the new descriptors using a circular neighborhood acquired from the initial square filter. These descriptors consider angular and radial transitions that occur in both the microstructures and macrostructures of image textures. Eventually, a more accurate and comprehensive visual representation is obtained. Furthermore, we offer a data fusion step based on a voting mechanism to integrate the retrieved data efficiently. We show many types of analyses that demonstrate LBP's and the suggested extensions' capability to extract discriminant features from X-ray images. The suggested method is tested on two different datasets with large diversities that include images from various demographics and regions. Several measures, including accuracy rate, precision, sensitivity, F-measure, and specificity, are used to evaluate the system's efficacy. According to the testing results, the proposed system provides a best successful recognition rate of 82.7 %.

通过x射线图像检测肺炎是确定任何可能的细菌或病毒性疾病的关键阶段。这一阶段的自动化至关重要，因为它加快了诊断过程。lbp擅长调查社区内的当地情况，汇总和分析当地的统计结果。本文提出了一种基于局部累积像素差的LBP描述符。我们使用从初始方形滤波器获得的圆形邻域构造新的描述符。这些描述符考虑了在图像纹理的微观结构和宏观结构中发生的角度和径向过渡。最终获得更准确、更全面的视觉表征。此外，我们提供了一个基于投票机制的数据融合步骤，以有效地整合检索到的数据。我们展示了许多类型的分析，证明了LBP和建议的扩展从x射线图像中提取判别特征的能力。建议的方法在两个不同的数据集上进行了测试，这些数据集具有很大的多样性，包括来自不同人口统计和地区的图像。包括准确率、精密度、灵敏度、f值和特异性在内的几个指标被用来评估系统的疗效。测试结果表明，该系统的最佳识别率为82.7 %。

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引用次数: 0

Linkage suspension sag estimation using the static equilibrium method 使用静态平衡法估算连杆悬架下垂度

IF 2.2 4区工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY

Journal of Engineering Research

Pub Date : 2025-09-01 DOI: 10.1016/j.jer.2024.07.013

Willy Prastiyo , Muhamad Maris Al Gifari , Wiesław Fiebig

Small amateur teams often struggle to estimate suspension performance in off-road motorcycle competitions due to limited access to advanced assessment equipment. Vehicle testing and validation are commonly performed through direct test rides, where improper setups can lead to loss of control, accidents, and costly repairs. This article aims to provide an economical and less sophisticated technique for engineering technicians working with linkage suspensions to estimate total sag and corresponding wheel travel. Initially, the wheel normal force and suspension geometry are measured and verified. The leverage ratio (LR) is then examined, and the forces in the relay arm (

F_{2 r}

) and shock absorber (

F_{2 a}

) are identified. By combining the graphs of

F_{2 r}

and

F_{2 a}

, sag and wheel travel can be determined based on the swingarm angular displacement. Three adjustment approaches are demonstrated: tuning the initial position of the swingarm, changing the spring stiffness and/or preload, and modifying the leverage ratio. Using the described technique, technicians can assess and reuse the noted LR,

F_{2 r}

and

F_{2 a}

curves to approximate the optimal suspension setting for specific sections or terrains during competitions.

由于先进的评估设备有限，小型业余团队常常难以评估越野摩托车比赛中的悬挂性能。车辆测试和验证通常通过直接测试进行，其中不适当的设置可能导致失去控制，事故和昂贵的维修。本文旨在为工程技术人员提供一种经济而不太复杂的技术，以估计连杆悬架的总垂度和相应的车轮行程。首先，测量和验证车轮法向力和悬架几何形状。然后检查杠杆比（LR），并确定继电器臂（F2r）和减震器（F2a）中的力。结合F2r和F2a的曲线图，可以根据摆臂角位移确定垂度和车轮行程。演示了三种调整方法：调整摆臂的初始位置，改变弹簧刚度和/或预紧力，以及修改杠杆比。使用上述技术，技术人员可以评估和重用著名的LR、F2r和F2a曲线，以在比赛中近似于特定路段或地形的最佳悬挂设置。

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引用次数: 0

A Southeast Asia National Aviation Company benchmarking by regret theory-based data envelopment analysis model 基于回归理论的数据包络分析模型对东南亚国家航空公司进行标杆分析

IF 2.2 4区工程技术 Q3 ENGINEERING, MULTIDISCIPLINARY

Journal of Engineering Research

Pub Date : 2025-09-01 DOI: 10.1016/j.jer.2024.07.005

Chia-Nan Wang, Phuong-Thuy Thi Nguyen, Nhat-Luong Nhieu

National airlines play a pivotal role in fostering economic growth, facilitating trade, and promoting tourism. With Asia's aviation economic expansion and diverse cultural landscapes, the aviation industry has a role in linking nations, facilitating cultural exchange, and enhancing cross-border cooperation. In the aftermath of the global COVID-19 pandemic, the aviation industry in Asia has faced unprecedented challenges. This study aims to provide an overview of the performance of nine national airlines in the Asian aviation market, using cross-efficiency evaluation combined with the Regret theory based on the DEA model. Traditional DEA models often utilize a self-evaluation mode to evaluate DMUs, resulting in drawbacks such as overestimating efficiency and incomplete ranking. Cross-efficiency evaluation has addressed these limitations. However, cross-efficiency evaluation overlooks the significance of the irrational psychology of decision-makers (DMs). Hence, this study utilizes the Regret theory to depict the regret aversion behavior of DMs. The integration of emotional factors in assessing operational performance offers a holistic view of airlines' challenges and opportunities after the COVID-19 pandemic, ultimately facilitating informed decision-making and strategic planning for the industry's revival.

国家航空公司在促进经济增长、促进贸易和促进旅游业方面发挥着关键作用。随着亚洲航空经济的发展和文化景观的多样化，航空业在联系国家、促进文化交流和加强跨境合作方面发挥着重要作用。2019冠状病毒病全球大流行后，亚洲航空业面临前所未有的挑战。本研究旨在对亚洲航空市场上九家国家航空公司的绩效进行概述，采用交叉效率评价结合基于DEA模型的后悔理论。传统的DEA模型往往采用自评价模式来评价dmu，存在效率高估、排序不完整等缺点。交叉效率评估解决了这些限制。然而，交叉效率评价忽视了决策者非理性心理的重要性。因此，本研究运用后悔理论来描述dm的后悔厌恶行为。将情感因素整合到运营绩效评估中，可以全面了解航空公司在2019冠状病毒病大流行后面临的挑战和机遇，最终促进明智的决策和战略规划，以实现行业的复兴。

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引用次数: 0