To achieve hydrodynamic design excellence in Autonomous Underwater Vehicles(AUVs)largely depends on the accurate prediction of lift and drag forces.The study presents Computational Fluid Dynamics(CFD)-based lift and d...To achieve hydrodynamic design excellence in Autonomous Underwater Vehicles(AUVs)largely depends on the accurate prediction of lift and drag forces.The study presents Computational Fluid Dynamics(CFD)-based lift and drag estimations of a novel torpedo-shaped flight-style AUV with bow-wings.The horizontal bow-wings are provided to accommodate the electromagnetic arrays used to perform the cable detection and tracking operations near the seabed.The hydrodynamic performance of the AUV due to addition of these horizontal bow-wings is required to be investigated,particularly at the initial design stage.Hence,CFD techniques are employed to compute the lift and drag forces observed by the flight-style AUV,maneuvering underwater at different angles of attack and varying speeds.The Reynolds-Averaged Navier-Stokes Equations(RANSE)closure is achieved by employing the modified k-ϵ model and Two-Scale Wall Function(2-SWF)approach is used for boundary layer treatment.Further,the study also highlights the unique mesh refinement and solution-adaptive meshing techniques to perform the CFD simulations in Solidworks Flow Simulation(SWFS)environment.The drag polar curve for flight-style AUV with and without bow-wings is generated using the computed lift and drag coefficients.The curve provided essential insights for achieving hydrodynamically efficient and optimized AUV design.From the drag polar curve,it is revealed that due to horizontal bow-wings,the flight-style AUV is capable to generate higher lift with less drag and thus,it gives better lift-to-drag ratio compared to the AUV without bow-wings.Moreover,simulated results of axial drag observed by the AUV have also been compared with free-running experimental results and are found in good agreement.展开更多
本研究对齐鲁理工学院导师在指导学生论文草稿时提供的书面反馈(SWF)进行了调查。继Kumar和Stracke (2007)的研究之后,本研究着重分析了Holmes (2008)提出的三类主要言语行为在SWF中的类型和分布:(a) 引用(包括编辑、组织、内容);(b) 指...本研究对齐鲁理工学院导师在指导学生论文草稿时提供的书面反馈(SWF)进行了调查。继Kumar和Stracke (2007)的研究之后,本研究着重分析了Holmes (2008)提出的三类主要言语行为在SWF中的类型和分布:(a) 引用(包括编辑、组织、内容);(b) 指令(包括建议、问题、指导);以及(c) 表达(包括赞扬、批评、意见)。此外,研究还考察了非语言特征,如问号、感叹号、圆圈和下划线,以观察导师在互动过程中的情绪表达。研究结果表明,参考性反馈是SWF中最常见的类型,占275个实例中的130个(47.2%),其次是指令性反馈,占105个(38.2%)。相比之下,表达性反馈较为罕见,在数据中仅发现了40个(14.5%)。总体来看,大多数导师的SWF主要集中在编辑(102个,占37.6%),而意见(4个,占1.5%)和内容(6个,占2.2%)的反馈数量则相对较少。在识别出的394个非语言符号中,导师的SWF展现了他们的个人和心理表达。除了在许多学生的写作作业中经常缺席外,提供关于学生写作的SWF不仅对提高学生的写作能力起着关键作用,而且促进了学生的自主学习。This research examined supervisory written feedback (SWF) offered by supervisors to students at Qilu Institute of Technology during the thesis drafting process. Drawing upon the framework established by Kumar and Stracke (2007), the study concentrated on dissecting the categories and prevalence of three primary speech acts identified by Holmes (2008) within SWF: (a) referential feedback, which encompasses editing, organization, and content;(b) directive feedback, including suggestions, questions, and guidance;and (c) expressive feedback, covering praise, criticism, and opinions. Additionally, the study scrutinized nonverbal cues such as question marks, exclamation marks, circles, and underscores to gauge the emotional undertones of mentors during the feedback process. The findings revealed that referential feedback was the most frequent form of SWF, accounting for 130 out of 275 instances (47.2%), followed by directive feedback, which accounts for 105 instances (38.2%). In contrast, expressive feedback is relatively rare, with only 40 instances (14.5%) found in the data. Overall, the majority of supervisors’ SWFs are mainly focused on editing (102 instances, 37.6%), while feedback on opinions (4 instances, 1.5%) and content (6 instances, 2.2%) is relatively small. Among the 394 recognized nonverbal symbols, the supervisors’ SWF reflected their personal and psychological expressions. The study underscores the significance of SWF in student writing assignments, highlighting its dual role in enhancing writing proficiency and fostering self-regulated learning. Despite its frequent absence in student assignments, the provision of SWF is essential for guiding students toward academic excellence and encouraging autonomous learning practices.展开更多
基金supported in part by the National Natural Science Foundation of China(Grant Nos.52131101 and 52071153)in part by Hubei Natural Science Foundation for Innovation Groups(Grant No.2021CFA026).
文摘To achieve hydrodynamic design excellence in Autonomous Underwater Vehicles(AUVs)largely depends on the accurate prediction of lift and drag forces.The study presents Computational Fluid Dynamics(CFD)-based lift and drag estimations of a novel torpedo-shaped flight-style AUV with bow-wings.The horizontal bow-wings are provided to accommodate the electromagnetic arrays used to perform the cable detection and tracking operations near the seabed.The hydrodynamic performance of the AUV due to addition of these horizontal bow-wings is required to be investigated,particularly at the initial design stage.Hence,CFD techniques are employed to compute the lift and drag forces observed by the flight-style AUV,maneuvering underwater at different angles of attack and varying speeds.The Reynolds-Averaged Navier-Stokes Equations(RANSE)closure is achieved by employing the modified k-ϵ model and Two-Scale Wall Function(2-SWF)approach is used for boundary layer treatment.Further,the study also highlights the unique mesh refinement and solution-adaptive meshing techniques to perform the CFD simulations in Solidworks Flow Simulation(SWFS)environment.The drag polar curve for flight-style AUV with and without bow-wings is generated using the computed lift and drag coefficients.The curve provided essential insights for achieving hydrodynamically efficient and optimized AUV design.From the drag polar curve,it is revealed that due to horizontal bow-wings,the flight-style AUV is capable to generate higher lift with less drag and thus,it gives better lift-to-drag ratio compared to the AUV without bow-wings.Moreover,simulated results of axial drag observed by the AUV have also been compared with free-running experimental results and are found in good agreement.
文摘本研究对齐鲁理工学院导师在指导学生论文草稿时提供的书面反馈(SWF)进行了调查。继Kumar和Stracke (2007)的研究之后,本研究着重分析了Holmes (2008)提出的三类主要言语行为在SWF中的类型和分布:(a) 引用(包括编辑、组织、内容);(b) 指令(包括建议、问题、指导);以及(c) 表达(包括赞扬、批评、意见)。此外,研究还考察了非语言特征,如问号、感叹号、圆圈和下划线,以观察导师在互动过程中的情绪表达。研究结果表明,参考性反馈是SWF中最常见的类型,占275个实例中的130个(47.2%),其次是指令性反馈,占105个(38.2%)。相比之下,表达性反馈较为罕见,在数据中仅发现了40个(14.5%)。总体来看,大多数导师的SWF主要集中在编辑(102个,占37.6%),而意见(4个,占1.5%)和内容(6个,占2.2%)的反馈数量则相对较少。在识别出的394个非语言符号中,导师的SWF展现了他们的个人和心理表达。除了在许多学生的写作作业中经常缺席外,提供关于学生写作的SWF不仅对提高学生的写作能力起着关键作用,而且促进了学生的自主学习。This research examined supervisory written feedback (SWF) offered by supervisors to students at Qilu Institute of Technology during the thesis drafting process. Drawing upon the framework established by Kumar and Stracke (2007), the study concentrated on dissecting the categories and prevalence of three primary speech acts identified by Holmes (2008) within SWF: (a) referential feedback, which encompasses editing, organization, and content;(b) directive feedback, including suggestions, questions, and guidance;and (c) expressive feedback, covering praise, criticism, and opinions. Additionally, the study scrutinized nonverbal cues such as question marks, exclamation marks, circles, and underscores to gauge the emotional undertones of mentors during the feedback process. The findings revealed that referential feedback was the most frequent form of SWF, accounting for 130 out of 275 instances (47.2%), followed by directive feedback, which accounts for 105 instances (38.2%). In contrast, expressive feedback is relatively rare, with only 40 instances (14.5%) found in the data. Overall, the majority of supervisors’ SWFs are mainly focused on editing (102 instances, 37.6%), while feedback on opinions (4 instances, 1.5%) and content (6 instances, 2.2%) is relatively small. Among the 394 recognized nonverbal symbols, the supervisors’ SWF reflected their personal and psychological expressions. The study underscores the significance of SWF in student writing assignments, highlighting its dual role in enhancing writing proficiency and fostering self-regulated learning. Despite its frequent absence in student assignments, the provision of SWF is essential for guiding students toward academic excellence and encouraging autonomous learning practices.
