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Documentos governamentais Acesso aberto

G. P. Chaplin,

Letters: G. P. Chaplin; October 23, 1861; Boom Falls; Sierra Leone.

1861 - Gale Group | SAS Part 1

Artigo Acesso aberto Revisado por pares

Giordana Bonavolontà, Craig Lawson, Atif Riaz,

The reduction of sonic boom levels is the main challenge but also the key factor to start a new era of supersonic commercial flights. Since ... has banned supersonic flights overland for unacceptable sonic booms at the ground, and many research studies have ... carried out from that date to understand sonic boom generation, propagation and effects, both on the environment ... been developed with the attempt to reduce sonic boom annoyance to acceptable levels. In the last 20 ... methods and tools for the design of low boom supersonic aircraft. The exploration of unconventional configurations and ...

Tópico(s): Fluid Dynamics and Turbulent Flows

2023 - Multidisciplinary Digital Publishing Institute | Aerospace

Livro

National Bureau of Economic Research (NBER)

Documentos governamentais Acesso aberto

J. P.,

... J. P.; October 24, 1861 to Bro. Whipple; Boom Falls; Sierra Leone.

1861 - Gale Group | SAS Part 1

Artigo Acesso aberto Revisado por pares

Jinyang Li, Zhenyu Nie, Yunfei Chen, Deqiang Ge, Meiqing Li,

... it is necessary to keep the entire spray boom parallel to the crop canopy or ground and ... the crop canopy or ground. A high-performance boom active control system was developed for boom trapezoid suspension. The hydraulic system and hardware circuit of the boom control system were designed based on analyzing the ... models of valve-controlled hydraulic cylinders and active boom suspensions were developed. Step response and frequency domain ... Simulink simulations, and then key parameters of the boom suspension and hydraulic system were determined. A feedforward ...

Tópico(s): Plant responses to water stress

2023 - Multidisciplinary Digital Publishing Institute | Agriculture

Documentos governamentais Acesso aberto

Rev. G. P. Claflin,

Letters: Rev. G. P. Claflin; January 30, 1862; Boom Falls; Sierra Leone.

1862 - Gale Group | SAS Part 1

Artigo Revisado por pares

Andrew Lee, Juan M. Fernandez, Jacob G. Daye,

... extended and coiled states of thin-shelled composite booms with parabolic cross sections are investigated in this ... for improving the load-bearing performance of deployed booms. Inducing bistability through composite layups in parabolic booms would allow for controllable self-deployment due to ... less energetic coiled state when compared to monostable booms. An inextensional analytical model is used to predict ... of tape spring and collapsible tubular mast (CTM) booms with parabolic cross sections. The parabolic section is ...

Tópico(s): Dynamics and Control of Mechanical Systems

2023 - American Institute of Aeronautics and Astronautics | Journal of Spacecraft and Rockets

Documentos governamentais Acesso aberto

Rev. C. P; Claflin,

... P; Claflin; February 24, 1862 to Bro. Whipple; Boom Falls Station; Sierra Leone.

1862 - Gale Group | SAS Part 1

Artigo Revisado por pares

Li Wu, Karl Geiselhart,

... design a computational fluid dynamics (CFD)-based low-boom configuration that can be obtained from a Pareto ... the system-level trade between the target low-boom ground noise level and the overland range. The refined MDO method can generate a low-boom configuration that satisfies the mission requirements, has the ... weight and the longest range for the low-boom mission, trims the low-boom cruise flight with fuel redistributions, and has a reversed equivalent area distribution closely matching a low-boom target with ground noise level below 70 perceived ...

Tópico(s): Aerodynamics and Acoustics in Jet Flows

2022 - American Institute of Aeronautics and Astronautics | Journal of Aircraft

Documentos governamentais Acesso aberto

Richard Miles,

... Richard Miles; March 17, 1862 to Brother Whipple; Boom Falls Station; Sierra Leone.

1862 - Gale Group | SAS Part 1

Artigo Acesso aberto Revisado por pares

Junchao Yan, Xinyu Xue, Longfei Cui, Suming Ding, Wei Gu, Feixiang Le,

... behavior modeling and parameter optimization of the spray boom based on multi-body vibration were developed to study the influence of the boom sprayer’s motion in a complex working environment on the dynamic behavior of the spray boom. First, a geometric continuous model of spray boom vibration was established considering the influence of the boom sprayer body and boom suspension. Then, the dynamic behavior of the spray boom under step excitation was studied on a SWAN3WP-500 self-propelled boom spray experimental platform. The time-domain response of ...

Tópico(s): Civil and Geotechnical Engineering Research

2021 - Multidisciplinary Digital Publishing Institute | Applied Sciences

Documentos governamentais Acesso aberto

Rev H H Hinnman,

... Hinnman; May 06, 1862 to Rev G Whipple; Boom Falls; Sierra Leone.

1862 - Gale Group | SAS Part 1

Artigo Revisado por pares

Wu Li, Karl Geiselhart,

A mixed-fidelity low-boom multidisciplinary optimization (MDO) problem is formulated for integration of low-fidelity MDO and computational fluid dynamics (CFD)-based low-boom inverse design optimization. The mixed-fidelity low-boom MDO problem aims to enforce the weight consistency for CFD-based low-boom inverse design optimization: the optimum low-boom configuration is designed for the weight at the ... cruise of the same configuration for the low-boom overland mission. Moreover, it also seeks the optimum ...

Tópico(s): Aerospace and Aviation Technology

2021 - American Institute of Aeronautics and Astronautics | AIAA Journal

Documentos governamentais Acesso aberto

Letters: September 01, 1869 to Bro. Whipple; Boom Falls Station; Sierra Leone.

1869 - Gale Group | SAS Part 1

Artigo Acesso aberto Revisado por pares

Hanjie Dou, Changyuan Zhai, Liping Chen, Songlin Wang, Xiu Wang,

To ensure boom sprayer safety and spraying efficiency, the sprayer boom height must be adjusted during pesticide application. The field variation characteristics of the sprayer boom height are the basis of the boom balance adjustment. A boom height detection system based on ultrasonic sensors was ... the detection accuracy of an ultrasonic sensor. The boom height variation was greatest at the sides of the boom, and the primary frequencies of the boom height variation were concentrated within a low-frequency ...

Tópico(s): Smart Agriculture and AI

2021 - Institute of Electrical and Electronics Engineers | IEEE Access

Documentos governamentais Acesso aberto

G. P. Claflin,

... Claflin; December 26, 1865 to Rev. Geo. Whipple; Boom Falls; Sierra Leone.

1865 - Gale Group | SAS Part 1

Artigo Acesso aberto Revisado por pares

Wu Li, Karl Geiselhart,

Conceptual design of low-boom supersonic aircraft is heavily dictated by aircraft volume and lift distributions. These unique design characteristics make it a challenge to ... and trim requirements) during design optimization. This low-boom design challenge is resolved by using reversed equivalent area targets for low-fidelity low-boom inverse design and a block coordinate optimization (BCO) ... for multidisciplinary design optimization (MDO). The corresponding low-boom MDO problem includes aircraft mission constraints on ranges, ...

Tópico(s): Probabilistic and Robust Engineering Design

2020 - American Institute of Aeronautics and Astronautics | AIAA Journal

Primary Document -- Manuscript Acesso aberto

Press cuttings: The Recruiting Boom. Bristol. Local Records. L.R. 65/20. Book.

0000 - Gale Group | ArchivesUnbound Women-War

Artigo Acesso aberto Revisado por pares

Sicong Wang, Mark Schenk, Shengyuan Jiang, Andrew Viquerat,

Deployable coilable booms are extendible structures that have been used in a number of space and terrestrial applications. Fiber reinforced polymer (FRP) composite variants of these deployable booms have advantages over the metallic versions in the ... deployment failure mode called ‘blossoming’, in which the boom unwinds and extends within the deployment mechanism, can ... if an excessive load is applied to the boom tip. Blossoming can be mitigated by using compression rollers which radially constrain the coiled boom. An energy method is used to model the ...

Tópico(s): Dynamics and Control of Mechanical Systems

2020 - Elsevier BV | Thin-Walled Structures

Documentos governamentais Acesso aberto

Rev. John S. Brooks,

... Rev. Geo. Whipple, Cor. Sec. A. M. A.; Boom River; Sierra Leone.

1852 - Gale Group | SAS Part 1

Artigo Acesso aberto Revisado por pares

Longfei Cui, Xinyu Xue, Feixiang Le, Hanping Mao, Suming Ding,

Boom sprayer is one of the most commonly used plant protection machinery for spraying pesticide. Studies have ... the uniformity of spray distribution patterns. As the boom is a large and flexible structure, boom rolling leads to overlapping and leakage of the pesticides. In order to improve spray uniformity, the boom attitude should be kept parallel to the ground slope or to the crop canopy beneath the boom. Passive suspension can attenuate frequencies above its resonance ... but nothing can be done to align the boom to the sloping ground. Therefore, an active suspension ...

Tópico(s): Soil Mechanics and Vehicle Dynamics

2019 - Chinese Society of Agricultural Engineering | International journal of agricultural and biological engineering