西北工业大学学报 Pub Date : 2023-06-01 DOI: 10.1051/jnwpu/20234130579

Dongxia Li, Siyu Song, Haitao Liu

{"title":"A trajectory optimization method for UAV cascade relay broadcast communication system","authors":"Dongxia Li, Siyu Song, Haitao Liu","doi":"10.1051/jnwpu/20234130579","DOIUrl":"https://doi.org/10.1051/jnwpu/20234130579","url":null,"abstract":"An unmanned aerial vehicle's(UAV) trajectory optimization is an important way to improve the performance of its relay communication system. The trajectory optimization method for the UAV cascade relay broadcast communication system that uses the decoding and forwarding protocols is studied. Firstly, the expressions of the signal-to-noise ratio of the UAV and the user are given. Then, a joint trajectory optimization method and a distributed trajectory optimization method for cascaded UAVs based on the minimized maximum user interruption probability are proposed. The transmission performance of the system link that uses the two trajectory optimization methods is studied; the mathematical expressions of the relay communication system's traverse capacity and the outage probability of a single user are given. Finally, the influence of the relay communication system's characteristic parameters on the optimal trajectory of the cascade relay UAV and its performance are verified with computer simulations. The simulation results show that the performance of the two trajectory optimization methods is basically the same, thus verifying the effectiveness of the trajectory optimization criterion.","PeriodicalId":39691,"journal":{"name":"西北工业大学学报","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45582194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Pareto-optimal control of relative motion in the orbital maneuvering problem of spacecraft with finite thrust 有限推力航天器轨道机动问题中相对运动的pareto最优控制

西北工业大学学报 Pub Date : 2023-06-01 DOI: 10.1051/jnwpu/20234130529

S. Ishkov, G. A. Filippov, Xiao Zhou, Changqing Wang

引用次数: 0

Search task oriented path planning method of airborne radar network 面向搜索任务的机载雷达网络路径规划方法

西北工业大学学报 Pub Date : 2023-06-01 DOI: 10.1051/jnwpu/20234130568

Ting Qin, Tao He, Jindong Lyu, Junkun Yan, Tianqi Qin, Hongzhi Liu

引用次数: 0

Research on the safe separation corridor of the combined aircraft and its generation method 组合飞机安全分离廊道及其生成方法研究

西北工业大学学报 Pub Date : 2023-06-01 DOI: 10.1051/jnwpu/20234130480

Yihua Pan, Qingsong Zhang, Jincheng Zhang, Chengzhi Cai, Shan Jia

引用次数: 0

Hydrodynamic performance study of manta ray gliding in groups 蝠鲼群体滑翔的水动力性能研究

西北工业大学学报 Pub Date : 2023-06-01 DOI: 10.1051/jnwpu/20234130595

Pengcheng Gao, Qiaogao Huang, Dong Song, Guang-xu Pan, Yunlong Ma

{"title":"Hydrodynamic performance study of manta ray gliding in groups","authors":"Pengcheng Gao, Qiaogao Huang, Dong Song, Guang-xu Pan, Yunlong Ma","doi":"10.1051/jnwpu/20234130595","DOIUrl":"https://doi.org/10.1051/jnwpu/20234130595","url":null,"abstract":"To investigate the effect of group gliding formation on the hydrodynamic performance of manta rays, numerical simulations were used to investigate the drag, the lift and pressure distribution of multiple manta rays in tandem, triangular and diamond-shaped arrangements. The simulation results show that the leader manta ray at the head of the group always suffers the least drag, and in most cases, the companion manta ray at the tail of the group suffers the most drag. The pressure distribution in the flow field shows that the drag reduction effect mainly comes from the distribution of high pressure and low pressure zones among the individual rays in the cluster, the high pressure zone is beneficial to the manta rays at the front of the group, and under certain circumstances, the presence of low pressure zone generates forward suction to reduce the drag of the manta rays at the end of the group. It is found that when manta rays glide in \"two in front and one at the back\", four-body diamond, six-body tandem and six-body diamond arrangement, the average drag of the system can be reduced, which provides theoretical guidance for the formation of bionic vehicle groups.","PeriodicalId":39691,"journal":{"name":"西北工业大学学报","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48119032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A novel noise assessment method based on human core competency 一种基于人的核心竞争力的噪声评价方法

西北工业大学学报 Pub Date : 2023-06-01 DOI: 10.1051/jnwpu/20234130621

Xiaoyan Zhang, Jia'ao Cheng, Hongjun Xue

{"title":"A novel noise assessment method based on human core competency","authors":"Xiaoyan Zhang, Jia'ao Cheng, Hongjun Xue","doi":"10.1051/jnwpu/20234130621","DOIUrl":"https://doi.org/10.1051/jnwpu/20234130621","url":null,"abstract":"The tough noise environment in helicopter cockpit can passively influence pilots in mental and physical way, weaken their core competency, and as a result, maybe causing pilot error and even accidents. The current research can evaluate the physical characteristics of noise and its impact on emotion such as noise annoyance, but it ignores the impact of cockpit noise on human competence. Therefore, this paper establishes a noise evaluation and prediction model based on core competence with task performance, cognitive load and eye movement data. Experiment is designed and implemented in three noise levels and three task difficulties to verify the model. The results indicate that: 1) core competency and task accuracy decline in higher noise levels significantly. 2) the noise assessment method based on core competency can accurately predict the influence of noise on human performance. This novel method can quantitatively reflect the impact of noise changes on human performance in emergency condition. It can expand the connotation of noise evaluation, provide the evaluation and control of cockpit noise with theoretical explanations, and provide the optimization design of helicopter cockpit with practical data.","PeriodicalId":39691,"journal":{"name":"西北工业大学学报","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47013651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental study of hydrodynamic performances of pre-swirl pumpjet propeller 预旋泵射流推进器水动力性能的实验研究

西北工业大学学报 Pub Date : 2023-06-01 DOI: 10.1051/jnwpu/20234130601

Denghui Qin, Qiaogao Huang, Guang-xu Pan, Fuzheng Li, Peng Han

{"title":"Experimental study of hydrodynamic performances of pre-swirl pumpjet propeller","authors":"Denghui Qin, Qiaogao Huang, Guang-xu Pan, Fuzheng Li, Peng Han","doi":"10.1051/jnwpu/20234130601","DOIUrl":"https://doi.org/10.1051/jnwpu/20234130601","url":null,"abstract":"A pre-swirl pumpjet propeller(PJP) is widely used in the new generation of quiet submarines all over the world, although the experimental study of its hydrodynamic performances is still rare. This paper carries out experimental tests of the pre-swirl PJP with a 9-blade stator and a 7-blade rotor in a cavitation water tunnel. The thrust coefficient and torque coefficient of the pre-swirl PJP in open water are tested with a force measurement device, and the wake flow field of the pre-swirl PJP is tested with a laser particle velocimetry system. The experimental results show that the rotor thrust coefficient, stator-duct thrust coefficient and rotor torque coefficient of the pre-swirl PJP decrease with increasing the advance coefficient J, but the absolute value of the torque coefficient of the stator-duct thrust increases with increasing J. The open water efficiency of the pre-swirl PJP reaches the maximum when J=1.0, being 61.91%. The thrust of the pre-swirl PJP is mainly provided by the rotor. In addition, the wake flow field of the pre-swirl PJP is composed of jet acceleration zone, hub low-speed zone and mixed zone. The transient velocity and average velocity in the wake flow field under different working conditions are obtained.","PeriodicalId":39691,"journal":{"name":"西北工业大学学报","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45703603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamics modeling and flight characteristics of folded multi-body aircraft 折叠多体飞机动力学建模与飞行特性

西北工业大学学报 Pub Date : 2023-06-01 DOI: 10.1051/jnwpu/20234130490

Yu Wang, Xiaoping Zhu, Zhou Zhou

引用次数: 0

Research on schedulability analysis algorithm of airborne multi partition system 机载多分区系统可调度性分析算法研究

西北工业大学学报 Pub Date : 2023-06-01 DOI: 10.1051/jnwpu/20234130557

Min Zhang, Junsheng Wu, Xining Cui, Jingchang Sun

{"title":"Research on schedulability analysis algorithm of airborne multi partition system","authors":"Min Zhang, Junsheng Wu, Xining Cui, Jingchang Sun","doi":"10.1051/jnwpu/20234130557","DOIUrl":"https://doi.org/10.1051/jnwpu/20234130557","url":null,"abstract":"Partition operating system conforming to ARINC653 is widely used in airborne to support application software integration. Under the two-level scheduling model for partition operating system, the demanding real-time requirements of airborne software are usually difficult to obtain effective deterministic guarantee, so it is very important to analyze the schedulability of the system. Judging whether the scheduling table can meet the real-time requirements of the process in the partition through the schedulability analysis algorithm is an effective means to ensure that all processes in the system complete the computing task within the specified time. Based on the method of operations research and the introduction of virtual process, a schedulability analysis algorithm for multi partition system is designed, and the numerical verification is carried out. The verification results show that the algorithm can accurately judge whether the scheduling table matches the process time attribute, give the qualitative analysis conclusion of whether the system can be scheduled, help the system integrator to verify the rationality of the scheduling table before the actual operation of the system, and reduce the risk of test and flight test.","PeriodicalId":39691,"journal":{"name":"西北工业大学学报","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44781825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Degradation prediction method of PEMFC based on deep learning hybrid model integrating ARIMA and LSTM 基于ARIMA和LSTM集成的深度学习混合模型的PEMFC退化预测方法

西北工业大学学报 Pub Date : 2023-06-01 DOI: 10.1051/jnwpu/20234130464

Yufan Zhang, Yuren Li, Rui Ma, Hongyu Zhang, Bo Liang

引用次数: 0

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