scholarly journals The Making of a Flight Feather: Bio-architectural Principles and Adaptation

Cell ◽  
2019 ◽  
Vol 179 (6) ◽  
pp. 1409-1423.e17 ◽  
Author(s):  
Wei-Ling Chang ◽  
Hao Wu ◽  
Yu-Kun Chiu ◽  
Shuo Wang ◽  
Ting-Xin Jiang ◽  
...  
Keyword(s):  
Flight Feather ◽  
Architectural Principles

Discovering Architecture

2017 ◽  
Author(s):  
Matthew Walker
Keyword(s):  
Early Modern ◽  
Ancient World ◽  
Ancient Athens ◽  
Early Modern English ◽  
Degree Of Confidence ◽  
Architectural Principles ◽  
The Subject ◽  
Architectural Knowledge

This chapter deals with the genesis of architectural knowledge. In particular, it explores those rare moments when early modern English authors wrote about newly discovered examples of ancient architecture, the most important forms of architectural knowledge that existed. I will discuss three such accounts (all published in the Philosophical Transactions) of Roman York, Palmyra, and ancient Athens. These three texts share a preoccupation with truth and accuracy, as befitted the task of communicating highly sought-after architectural knowledge. They also demonstrate the degree of confidence of English writers in this period, not only in how they interpreted ancient architecture, but also in how they sought to criticize previous European authors on the subject. But most importantly, these texts reveal the extent of English intellectuals’ knowledge of the architectural principles of the ancient world and how that knowledge was in a state of flux.

scholarly journals Large-Scale Object Monitoring in Internet-of-Things: Energy-Efficient Perspectives

Electronics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 461
Author(s):  
Yongbin Yim ◽  
Euisin Lee ◽  
Seungmin Oh
Keyword(s):  
Energy Efficient ◽  
Large Scale ◽  
Future Research ◽  
Technological Evolution ◽  
Node Density ◽  
Mobile Objects ◽  
Research Challenges ◽  
Energy Efficient Communication ◽  
Efficient Communication ◽  
Architectural Principles

Recently, the demand for monitoring a certain object covering large and dynamic scopes such as wildfires, glaciers, and radioactive contaminations, called large-scale fluid objects (LFOs), is coming to the fore due to disasters and catastrophes that lately happened. This article provides an analytic comparison of such LFOs and typical individual mobile objects (IMOs), namely animals, humans, vehicles, etc., to figure out inherent characteristics of LFOs. Since energy-efficient monitoring of IMOs has been intensively researched so far, but such inherent properties of LFOs hinder the direct adaptation of legacy technologies for IMOs, this article surveys technological evolution and advances of LFOs along with ones of IMOs. Based on the communication cost perspective correlated to energy efficiency, three technological phases, namely concentration, integration, and abbreviation, are defined in this article. By reviewing various methods and strategies employed by existing works with the three phases, this article concludes that LFO monitoring should achieve not only decoupling from node density and network structure but also trading off quantitative reduction against qualitative loss as architectural principles of energy-efficient communication to break through inherent properties of LFOs. Future research challenges related to this topic are also discussed.

scholarly journals Allometry of the Duration of Flight Feather Molt in Birds

PLoS Biology ◽  
2009 ◽  
Vol 7 (6) ◽  
pp. e1000132 ◽  
Author(s):  
Sievert Rohwer ◽  
Robert E. Ricklefs ◽  
Vanya G. Rohwer ◽  
Michelle M. Copple
Keyword(s):  
Flight Feather ◽  
Feather Molt

Drag Reduction Study about Bird Feather Herringbone Riblets

2013 ◽  
Vol 461 ◽  
pp. 201-205 ◽  
Author(s):  
Hua Wei Chen ◽  
Fu Gang Rao ◽  
De Yuan Zhang ◽  
Xiao Peng Shang
Keyword(s):  
Drag Reduction ◽  
Structural Parameters ◽  
Reduction Rate ◽  
Reduction Mechanism ◽  
Surface Drag ◽  
Flight Feather ◽  
Hollow Shaft ◽  
Smooth Edge ◽  
Bird Feather ◽  
Wild Goose

Flying bird has gradually formed airworthy structures e.g. streamlined shape and hollow shaft of feather to improve flying performance by millions of years natural selection. As typical property of flight feather, herringbone-type riblets can be observed along the shaft of each feather, which caused by perfect alignment of barbs. Why bird feather have such herringbone-type riblets has not been extensively discussed until now. In this paper, microstructures of secondary feathers are investigated through SEM photo of various birds involving adult pigeons, wild goose and magpie. Their structural parameters of herringbone riblets of secondary flight feather are statistically obtained. Based on quantitative analysis of feathers structure, one novel biomimetic herringbone riblets with narrow smooth edge are proposed to reduce surface drag. In comparison with traditional microgroove riblets and other drag reduction structures, the drag reduction rate of the proposed biomimetic herringbone riblets is experimentally clarified up to 15%, much higher than others. Moreover, the drag reduction mechanism of herringbone riblets are also confirmed and exploited by CFD.

scholarly journals DESAIN MASJID DI KECAMATAN TOMIA TIMUR KABUPATEN WAKATOBI PROVINSI SULAWESI TENGGARA DENGAN PRINSIP-PRINSIP ARSITEKTUR EKLEKTIK

Vitruvian ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 81
Author(s):  
Muhammad Zakaria Umar ◽  
Masfan Agus
Keyword(s):  
Grounded Theory ◽  
Secondary Data ◽  
Primary Data ◽  
Alternative Form ◽  
School Buildings ◽  
Architectural Elements ◽  
Grounded Theory Method ◽  
Double Decker ◽  
Architectural Principles ◽  
The City

ABSTRAKMasjid-masjid di Indonesia khususnya di Jawa juga tidak bebas dari pengaruh kebudayaan lokal. Hal ini disebabkan manusia Indonesia pada umumnya bersifat eklektik, maka bentuk masjid-masjid di Indonesia pun bergaya campuran sisa-sisa kebudayaan Hindu, bangunan-bangunan India, atau Turki. Saat ini kebudayaan Buton kembali direvitalisasi seperti bentuk atap Malige terdapat pada bangunan sekolah, pertokoan, dan perkantoran. Sedangkan bentuk masjid Keraton Buton dan rumah tradisional Buton Malige belum pernah diadaptasi menjadi alternatif bentukan masjid di Kota Baubau. Penelitian ini ditujukan untuk mendesain masjid skala kecamatan di Kelurahan Tongano Barat, Kecamatan Tomia Timur, Kabupaten Wakatobi dengan prinsip-prinsip arsitektur eklektik terhadap masjid Keraton Buton dan rumah tradisional Buton Malige. Penelitian ini menggunakan metode grounded theory dengan pendekatan kualitatif. Sumber data terdiri dari data primer dan data sekunder. Data dikumpulkan dengan cara observasi, wawancara, dan dokumentasi. Data dianalisis dengan cara data direduksi, disajikan, dan disimpulkan. Penelitian ini disimpulkan bahwa elemen-elemen arsitektural masjid di Kecamatan Tomia Timur, Kabupaten Wakatobi, Provinsi Sulawesi Tenggara yang dimodifikasi dari bangunan Masjid Agung tradisional Keraton Buton adalah denah masjid, jendela masjid, tangga eksterior masjid, dan fondasi masjid sedangkan dari rumah tradisional Buton Malige adalah rumah atap bersusun (Malige) serta masjid berbentuk rumah panggung. ABSTRACTMosques in Indonesia especially in Java are also not free from the influence of local culture. This is because Indonesian people are generally eclectic, so the form of our mosques are a mixture of remnants of Hindu culture, Indian buildings, or Turkey. Nowadays, Buton culture has been revitalized like the shape of the Malige roof on school buildings, shops, and offices. While the form of the Palace of Buton mosque and the traditional house of Buton Malige have never been adapted to be an alternative form of a mosque in the City of Baubau. This research is intended to design a sub-scale mosque in the West Tongano Village, Tomia Timur District, Wakatobi Regency with eclectic architectural principles towards the Keraton Buton mosque and the traditional house of Buton Malige. This study uses a grounded theory method with a qualitative approach. Data sources consist of primary data and secondary data. Data collected by observation, interview, and documentation. Data were analyzed by means of data reduced, presented, and concluded. This study concluded that the architectural elements of the mosque in Tomia Timur Subdistrict, Wakatobi Regency, Southeast Sulawesi Province which were modified from the traditional Great Mosque building of the Keraton Buton were mosque plans, mosque windows, mosque exterior stairs, and mosque foundations, while from the traditional houses of Buton Malige were a double-decker roof house (Malige) and a mosque on stilts.

In vivo strains in pigeon flight feather shafts: implications for structural design

1998 ◽  
Vol 201 (22) ◽  
pp. 3057-3065 ◽  
Author(s):  
WR Corning ◽  
AA Biewener
Keyword(s):  
Safety Factor ◽  
Tensile Strain ◽  
Columba Livia ◽  
Failure Stress ◽  
Metal Foil ◽  
Bending Tests ◽  
Flight Feather ◽  
Four Point Bending ◽  
The Mean

To evaluate the safety factor for flight feather shafts, in vivo strains were recorded during free flight from the dorsal surface of a variety of flight feathers of captive pigeons (Columba livia) using metal foil strain gauges. Strains recorded while the birds flew at a slow speed (approximately 5-6 m s-1) were used to calculate functional stresses on the basis of published values for the elastic modulus of feather keratin. These stresses were then compared with measurements of the failure stress obtained from four-point bending tests of whole sections of the rachis at a similar location. Recorded strains followed an oscillatory pattern, changing from tensile strain during the upstroke to compressive strain during the downstroke. Peak compressive strains were 2.2+/-0. 9 times (mean +/- s.d.) greater than peak tensile strains. Tensile strain peaks were generally not as large in more proximal flight feathers. Maximal compressive strains averaged -0.0033+/-0.0012 and occurred late in the downstroke. Bending tests demonstrated that feather shafts are most likely to fail through local buckling of their compact keratin cortex. A comparison of the mean (8.3 MPa) and maximum (15.7 MPa) peak stresses calculated from the in vivo strain recordings with the mean failure stress measured in four-point bending (137 MPa) yields a safety factor of between 9 and 17. Under more strenuous flight conditions, feather stresses are estimated to be 1.4-fold higher, reducing their safety factor to the range 6-12. These values seem high, considering that the safety factor of the humerus of pigeons has been estimated to be between 1.9 and 3.5. Several hypotheses explaining this difference in safety factor are considered, but the most reasonable explanation appears to be that flexural stiffness is more critical than strength to feather shaft performance.

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