Academic literature on the topic 'Three column concept'
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Journal articles on the topic "Three column concept"
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Sameer, M. Mohamed, Keerthy Chandra Bassetty, and V. Singaravadivelu. "Functional Outcome Analysis of Fixation of Tibial Plateau Fractures using the Three-column Concept." Journal of Orthopaedic Case Reports 12, no. 5 (2022): 6–10. http://dx.doi.org/10.13107/jocr.2022.v12.i05.2792.
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Aim: The aim of this study was to study the functional and radiological outcome after surgical fixation of complex intra-articular tibial plateau fractures managed by three-column concept. Materials and Methods: Ten patients with complex intra-articular tibial plateau fractures were included in this study. They were classified according to the three-column concept based on X-ray and computed tomography. All of them underwent osteosynthesis after meticulous planning and the columns were addressed using combined approaches. Results: We obtained good to excellent radiological and functional outcomes with the column-based fixation of the intra-articular tibial plateau fractures. About 90% of the patients were able to return to pre-injury level of activity without complications. Conclusion: The posterior column is a vital component of the tibial plateau and needs to be separately addressed. Three-column concept is a beneficial adjunct, especially in complex and biplanar intra-articular tibial plateau fractures, both as a diagnostic and a pre-operative planning tool.
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Diamante, G. A. C., P. V. T. Marinho, C. C. Zani, and M. V. Bahr Arias. "Ex-vivo evaluation of the three-column concept in canine thoracolumbar fractures." Arquivo Brasileiro de Medicina Veterinária e Zootecnia 72, no. 4 (2020): 1221–30. http://dx.doi.org/10.1590/1678-4162-11533.
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ABSTRACT Traumatic events such as a motor vehicle accident or falling from heights are very common in veterinary medicine and often lead to vertebral fracture-luxation with concomitant spinal cord injuries, mostly in the thoracolumbar spine. The purpose of this cadaveric biomechanical study was to determine the feasibility of the three-column concept in canine thoracolumbar segments with induced fractures. Eighteen Functional Spinal Units (FSU) of the thoracolumbar segments (T12-L2) were collected from 18 medium-sized adult dog cadavers and were subjected to flexion-extension and lateral bending tests so that range of motion (ROM) was recorded with a goniometer. Fractures were induced by compressive loads applied by a universal testing machine (EMIC®). After this, specimens were screened using computed tomography (CT) and the fractures were graded as affecting one, two or three columns, and divided into groups A, B, and C, respectively. Post-fracture range of motion (ROM) was compared with the previous results. Groups B and C (with fractures in two or three columns) had instability in the two axes evaluated (P<0.05). The outcomes of this study support the applicability of the three-column theory to thoracolumbar spines of dogs, as the FSUs that suffered fractures in two or more columns showed axial instability.
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Patel, Nishiben, Krishna R. Gupta, and Milind J. Umekar. "An Overview of Monolithic Column: Types, Parameters and Applications." Journal of Drug Delivery and Therapeutics 12, no. 4-S (2022): 223–31. http://dx.doi.org/10.22270/jddt.v12i4-s.5521.
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The column is the main component for chromatographic separation. Nowadays, monolithic columns are graining more popularity in the field of separation media for liquid chromatography. The monolith columns possess great potential as compared to the conventional packed column in terms of preparing complex mixtures. These columns provide various properties like higher permeability, high-efficiency fast separations, high flow rate with lower backpressure, fast mass transfer kinetics with a high binding capacity. It is categories into three columns and they are organic monolithic column, inorganic monolithic column and hybrid monolithic column and all three types of monolithic column differ through their porous properties. In this review, the various advantage of the high-efficiency monolithic column with recent advances, the origin of the concept, the various parameter of the monolithic stationary phase and the application of monolithic columns are illustrated. It is better column in comparison of selectivity, reproducibility and performance.
 Keywords: Monolithic column, Packed columns, Inorganic and organic monolithic column, Column parameters, Pharmaceutical Applications
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Joseph, Anitha, Lalu Mangal, and Precy Sara George. "Coupled dynamic response of a three-column mini TLP." Journal of Naval Architecture and Marine Engineering 6, no. 2 (2010): 52–61. http://dx.doi.org/10.3329/jname.v6i2.2789.
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For the development of deepwater marginal fields, many new platform concepts and designs are on the anvil. The mini TLP is a proven concept in this regard wherein an optimised conventional TLP system economically and efficiently serves in developing small marginal deepwater reserves. Various new geometric configurations and designs of mini TLPs are reported in the literature. This paper presents a new geometric configuration which could be a better alternative to an existing configuration. A 3-column mini TLP is designed and its platform-mooring coupled dynamic behaviour is investigated and compared with an existing 4-column mini TLP. The numerical investigation is carried out for the 1:56 scaled model using a finite element computer program suitable for compliant offshore platforms. A combination wave force model with diffraction-radiation loading on large members and Morison loading on slender members is adopted for computing the non-linear dynamic response of the structure. The effects of parameters such as pretension in tethers and wave approach angle have been studied. The results obtained are compared with published results of the 4-column mini TLP. It is found that the dynamic responses of the 3-column mini TLP are close to the 4-column mini TLP with relatively higher surge and tether tension. Accounting for this in the design stage, the newly designed structure could be a promising candidate which can be used as an alternative to the 4-column mini TLP. Reducing the number of columns from four to three has added advantages in terms of cost and time during fabrication, installation and maintenance of the platform. Keywords: Deepwater structures; Coupled dynamics; Finite element method; Mini TLP; Nonlinear dynamicanalysis. DOI: 10.3329/jname.v6i2.2789
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Louis, R. "Spinal stability as defined by the three-column spine concept." Anatomia Clinica 7, no. 1 (1985): 33–42. http://dx.doi.org/10.1007/bf01654627.
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Azmi, Yusuf Iskandar, Nik Aslam Hafiz Nik Omar, Kok Shien Ng, Ahmad Safuan A. Rashid, Mazidah Mukri, and Yee Ming Chew. "Influence of Column Length on Settlement Performance of Floating Stone Column in Soft Clay." Journal of Advanced Research in Applied Mechanics 132, no. 1 (2025): 60–69. https://doi.org/10.37934/aram.132.1.6069.
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This paper presents the experimental solutions for the influence of length to the behavior and settlement performance of stone column. Laboratory experiments were conducted to compare the results between the settlement performance of end bearing stone columns and floating stone columns. Unit cell concept is used to idealize the settlement performance of large column group under the uniform load. The parameters that investigated are the column length to diameter ratio. This experimental investigation used a small-scale unit cell model tank and investigated the column length of a single column. Furthermore, the physical test involved the use of a custom-made stone column model, constructed with a rectangular steel frame measuring 600 mm in height and 260*260 mm in length and width. The experiment incorporated three different column heights: 400 mm, 320 mm, and 240 mm. Additionally, three distinct area replacement ratios of 33%, 23% and 15% were employed in these testing experiments. The results indicated that an increase in the length of stone columns correlates with a reduction in settlement, together with the increase ability to dissipate excess water pressure leading to a faster consolidation rate. The settlement performance was compared with existing analytical solution where reasonable agreement was obtained.
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Utomo, Dwikora Novembri, and Januar Ari Subiantoro. "CORRELATION BETWEEN THREE COLUMN CONCEPT CLASSIFICATION AND INTERNAL FIXATION PROCEDURE OF TIBIAL PLATEAU PATIENTS AT DR. SOETOMO HOSPITAL." (JOINTS) Journal Orthopaedi and Traumatology Surabaya 7, no. 1 (2019): 1. http://dx.doi.org/10.20473/joints.v7i1.2018.1-11.
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Background: Tibial Plateau Fracture is one of the most common case seen in orthopaedics and the most classification system used is Schaetzker Classification. This classification is using X ray photograph to classify the fracture and it has limitation to describing a posterior column in tibial plateau fracture since X-ray is a 2D projection. Nowadays surgeon over the world start to using Three Column concept classification because it has a better image of 3D visualization of tibial plateau. Purpose: To know which one classification is more accurate in describing tibial plateau fracture in Dr. Soetomo Hospital period January 2015 until September 2017.Methods: This study is retrospective study, we collected data of patients with Tibial Plateau fracture that has been operated in Dr. Soetomo hospital from January 2015 – September 2017.Results: From the study found 24 patients that match with inclusion criteria. All patients are classified with Schaetzker and Three Column Classification. The most type of fracture based on Schaetzker Classification is Type 2 (7 patients) and based on Three Column Classification is type Three Column (11 patients) and the most action in Three Column type is Internal Fixation with double plate insertion (55 %).Conclusion: Three Column Classification is more accurate to describe type fracture in posterior part than Schaetzker. Three Column Classification is recommended to make easier decision for Tibial Plateau fracture treatment and prevent any loss of correction.
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Teddy, Livian, Gagoek Hardiman, N. Nuroji, and Sri Tudjono. "The New Method in Calculating Columns and Beams Dimensions That Meets Requirements of The Strong Column-Weak Beam and Non-Soft Story." Journal of Architectural Design and Urbanism 1, no. 2 (2019): 1. http://dx.doi.org/10.14710/jadu.v1i2.4492.
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Situated at an earthquake prone area, buildings planning in Indonesia must implement earthquake resistant building principles. One of these principles is determining dimensions of columns and beams in the process of architectural designing.This act eventually affects the behaviour of the strong column-weak beam and the probability of bending failure due to soft story. At present time, there are no simple rules architects can use in calculating the dimensions of beams and columns that meet the criteria for strong column-weak beam and non-soft story. This paper is an effort to provide an input to the architects in designing the dimensions of the columns and beams. This research is a review result of three theories namely: 1). The theory of columns and beams preliminary design, 2). The theory of the strong column-weak beam concept, and 3). The theory of soft story and column slenderness. Those theories were then synthesized into a spreadsheet. To meet the criteria for strong column-weak beam and non-soft story, the following procedures must be done : 1). Determine the columns’ dimensions according to 0.15% of the columns’ cumulative tributary area, 2). Determine the beams’ dimensions according to 1/12 of the beams’ span and the beams’ plastic modulus, 3). Determine the columns’ dimensions and the columns’plastic modulus, 4). Determine the columns’ height based on the column slenderness criteria, and 5). Compare the columns plastic modulus and the beams plastic modulus and check whether they meet the criteria “the columns’plastic modulus ≥ 1.2 * the beams’ plastic modulus”.
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Sundaravadivel, Subramanian, Manickam Karunya, and A. Kumarasamy Thiyagaraj. "Functional outcomes of proximal tibial fractures treated by open reduction and internal fixation: A hospital based prospective study." LatinAmericanJournalof Pharmacy 42, no. 6 (2023): 53–60. https://doi.org/10.5281/zenodo.8412436.
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Objectives: The primary objective of the present study was to determine the functional outcome (using modified Rasmussen clinical scores) of proximal tibial fractures treated by open reduction and internal fixation (ORIF) using three column concept with a minimum follow up period of six months. We also determined the complications of proximal tibial fracture fixation. Methods: This was a prospective study conducted among patients (15-60 years of age, of both gender) with proximal tibia fractures treated using three column concept conducted in the Department of Orthopaedics of a tertiary healthcare hospital in south India between March 2018 and February 2020. Results: The present study included a total of 60 patients with a mean (SD) age of 38.72 years (3.21). The proportion of males and females were 81.7% and 18.3% respectively. Road traffic accidents (RTA) were the most common mode of injury, followed by accidental fall from height (13.3%). Nearly one in four patients (23.3%) had one column involvement, 46.7% had two and 30.0% had three column involvement. In the present study, 6.7% patients had screw pullout, 10.0% had knee stiffness, and 10.0% had wound site infection. The mean (SD) duration of follow up was 12.5 months. Based on Rasmussen’s clinical scores, 20.0% patients had excellent, 63.3% had good, and 16.7% had fair scores. Importantly, none of the patients included in the present study had poor scores. The patients with one column involvement had good to excellent outcomes, in comparison with patientshaving two or three column involvement having fair outcomes (reduced scores) (p<0.05). Conclusion: Patients with one-column involvement (either medial or lateral) tended to achieve better functional outcomes than those with two or three columns involved. This distinction was statistically significant, emphasizing the impact of fracturecomplexity on patient recovery.
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Arafah, Musa. "Fraktur Tibial Plateau Posterior; Klasifikasi Three Column Concept dan Tantangan Approach operasi." Saintika Medika 15, no. 1 (2019): 41. http://dx.doi.org/10.22219/sm.vol15.smumm1.8095.
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Fraktur tibial plateau posterior yang murni merupakan kasus yang jarang terjadi. Sistem klasifikasi terbaru berdasarkan CT scan yang menggunakan computed tomography (CT) imaging, sistem ini mampu mengidentifikasi jenis fraktur yang tidak termasuk dalam klasifikasi Schatzker dan AO (Orthopaedic Trauma Association). Penggunaan CT imaging menghasilkan gambaran lebih baik dalam mengidentifikasi potongan axial tibialplateau dan membaginya menjadi tiga bagian (three column concept) ;fraktur lateral, medial dan bikondilar. Sistem klasifikasi ini memungkinkan ahli bedah orthopaedi untuk merekonstruksi dan merencanakan approach yang lebih baik sebelum operasi. Penelitian ini merupakan laporan kasus seorang wanita, usia 41 tahun, dengan fraktur tertutup tibial plateau posterior kanan di Rumah Sakit Umum Daerah dr. Soetomo Surabaya, data bersumber dari rekam medis, pemeriksaan fisik, radiologis dan laboratorium. Diagnosa Fraktur tertutup tibial plateau bicondylar posterior kanan. Dengan mode of injury pasien terjatuh dari sepeda motor dengan posisi lutut fleksi dan posisi kondilus femurmedial varus dan rotasi internal. Berdasarkan CT imaging didapatkan dua fragmen posterior murni yaitu posteromedial dan posterolateal sehingga memberikan tantangan dalam menentukan approach operasi. Metode operasi yang dipilih menggunakan posterior approach dengan L-Incision dilanjutkan dengan pemasangan plat small locking T-plate dan 1/3 tubular plate disertai roofing menggunakan K-wire 1,4 mm. Hasil klinis pasca operasi pada minggu kedua belas diperoleh pasien dapat mobilisasi dengan baik. Fraktur dari tibial plateau posterior yang murni merupakan kasus yang jarang terjadi. Three column concept menggunakan CT imaging memudahkan identifikasi. Metode operasi posterior approach pada kasus tibial plateau posterior cukup menantang untuk seorang ahli bedah orthopaedi dibandingkan anteroposterior maupun posteromedial approach. Kelebihan posterior approach memungkinkan operator untuk merekonstruksi fraktur dengan lebih baik.
Books on the topic "Three column concept"
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Milbank, Alison. Holy Terrors. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198824466.003.0014.
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In Chapter 13, a range of writers, all belonging to the Christian occult group, the Order of the Golden Dawn, employ Gothic tropes to describe theurgic/magical mystical ascent, whereby the material world is raised to the spiritual. Arthur Machen made ecstasy the aim of literature, and his Three Impostors is a self-reflexive work in which embedded tales seek to engender this mystical alchemy, whereby the abject is theurgically raised. Evelyn Underhill takes the concept of the doppelgänger in A Column of Dust to a new place as a heuristic device to learn the love which alone makes knowledge transformative. Like Underhill, Charles Williams explores the redemptive power of the doppelgänger for his theology of reciprocity and exchange in Descent into Hell. Gothic tropes enable a spiritual education and find new ways to deal with the loss of meaning in the natural world.
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Wierzbicki, James. The Classical Music Mainstream. University of Illinois Press, 2017. http://dx.doi.org/10.5406/illinois/9780252040078.003.0008.
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This chapter looks at how the American Symphony Orchestra League reported that thirty million people in the U.S. are actively interested in concert music. This does not mean jazz, popular ditties, hillbilly dance-bands, hymn singing, or wedding marches, but classical music. Writer Virgil Thomson noted in his column that whereas during the previous year ticket buyers had spent $40 million on baseball, patrons of classical music had spent $45 million. This passion for what Thomson called “serious music” had been stirred even as World War II was in progress, and by the end of the Fifties it was still going strong. Never before has there been such an interest in music in America. The changed atmosphere had been apparent even just a few years after the war's end. For composers, this made the future seem very promising.
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Gale, Robert L. An Ambrose Bierce Companion. Greenwood, 2001. http://dx.doi.org/10.5040/9798400609718.
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Ambrose Bierce was born in 1842 and mysteriously disappeared in 1914. During his lifetime, he was a controversial and prolific writer, and there is growing interest in his works. As a Union soldier during the Civil War, he witnessed bloodshed and the atrocities of battle. After the war, he began a career as a journalist in San Francisco, where many of his newspaper columns were filled with venom and daring. In addition, he wrote war stories and tales of the supernatural, along with an assortment of poems. Today, he is probably best remembered as the author ofThe Devil's Dictionary,originally published asThe Cynic's Dictionaryin 1906. This reference is a guide to his life and writings. An opening essay overviews Bierce's contribution to literature and journalism, and a chronology summarizes the most important events in his life. The bulk of the Companion comprises alphabetically arranged entries on Bierce's major works and characters and on historical persons and writers who figured prominently in his life and career. Thus the volume provides coverage of Bierce's contemporaries, many of whom he satirized in his scathing newspaper columns. Many of the entries list works for further reading, and the book closes with a selected, general bibliography. Because of Bierce's concern with so many issues of his day, the volume offers a valuable perspective on American culture during the time in which he lived.
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Rosenkrantz, Timme, and Fradley Hamilton Garner. Harlem Jazz Adventures. The Scarecrow Press, Inc., 2012. https://doi.org/10.5040/9798881818944.
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Timme Rosenkrantz (1911–1969) was a Danish journalist, author, concert and record producer, radio show host, and entrepreneur with a consuming passion for jazz and little head for business. Known in Denmark and New York as the “Jazz Baron” because of his noble lineage, he was the first European journalist to cover the jazz scene in Harlem. Harlem Jazz Adventures: A European Baron’s Memoir, 1934–1969 recounts Rosenkrantz’s happy years in New York City, where he would produce jazz concerts, record top musicians and bands in his midtown apartment, organize a “dream band” for Timme Rosenkrantz and His Barrelhouse Barons, a 1938 RCA Victor recording, (DL) live in Harlem and run a record shop with his life companion, journalist and singer Inez Cavanaugh. A good friend of jazz impresario John Hammond, Rosenkrantz would become the James Boswell of the Harlem jazz scene. Duke Ellington, Art Tatum, Coleman Hawkins, Billie Holiday—there wasn’t a New York jazz musician unknown to “Honeysuckle Rosenkrantz,” as christened by Fats Waller. Drawing on the published Danish-language original Dus med Jazzen, and an unpublished English free translation (DL) by Rosenkrantz and Cavanaugh, translator-adapter Fradley Hamilton Garner gives polish and context to Rosenkrantz’s stories of meetings with Cecile and Louis Armstrong, Benny Carter, Willie “The Lion” Smith, Eddie Condon, Erroll Garner—whom Rosenkrantz discovered and was first to record—and many others. This book is a must-have for jazz lovers. Social historians interested in the intersection of race and the music business will find in Rosenkrantz’s memoir an invaluable primary source on Harlem’s social scene and its musical legacy.
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Öztorun, Namık Kemal, and Ezgi Öztorun Köroğlu. Steel Structures I. İstanbul University–Cerrahpaşa Press Serial Number: 88, 2025. https://doi.org/10.5152/4100.
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This book provides comprehensive information essential for both the design of new steel structures and the analysis of existing ones. It covers the fundamental principles of design, procedures, historical context, specifications, and the Turkish standard TS 498 for design loads. It also addresses probability and factor of safety, the application of steel in structures, the mechanical properties of structural steels, and an introductory comments on TS 498. The book covers fundamental concepts including the behavior of tension and compression members, methods for their analysis, and details regarding compound struts. Compound struts with uniform cross-sections, designs for them in groups I-II-III, struts with varying moment of inertia, and cross-ties are addressed. Essential information on Mohr’s Circle equations and the product moment of inertia are reminded. Subsequent chapters delve into beams, lateral buckling, and beam-columns, making distinctions between beams subjected exclusively to bending and those subjected to both axial loading and bending. Additionally, analysis of fasteners, such as rivets and bolts, include design factors like length, diameter, fastener spacing, weight, modes of failure, types of fastened connections, design assumptions and allowable stresses, and other design considerations are included. Similarly, different types of bolts, advantages, installation methods of high-strength bolts, allowable stresses, and design considerations are discussed. The design of fastened connections, including direct shear, pure moment connections, and eccentric load connections for fasteners in shear, along with the AISC recommendations and the method of instantaneous center of rotation are explained. Combined shear and torsion as a more complex scenario are also addressed. Design rules for TS 648 and allowable stresses for steel structures are presented in tabular form. Further chapters cover welding, discussing its advantages and disadvantages, types, classifications, symbols, quality, defects, and key issues related to inspection and control. Specific types of welds, such as butt and fillet welds, are examined, along with stresses in welded connections, theoretical considerations, effective areas of welds, and additional considerations. Finally, the book covers torsion, including plate girders, trusses, splice and connection design principles, and allowable stresses. These topics are explored in depth through illustrative examples, and the book concludes with a presentation of a previous three-course examination. A brief introduction is included in this book, but detailed examples are decided to be included in future Steel Structures II book.
Book chapters on the topic "Three column concept"
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Louis, René. "Spinal Stability and Instability as Defined by the Louis Three-Column Spine Concept." In Spinal Instability. Springer New York, 1993. http://dx.doi.org/10.1007/978-1-4613-9326-9_2.
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Wydra, Małgorzata, Grzegorz Sadowski, Piotr Dolny, and Jadwiga Fangrat. "Crack Propagation Analysis of Model Concrete Columns with BFRP Reinforcement Bars." In Springer Proceedings in Materials. Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-72955-3_43.
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AbstractAvailable studies on concrete structural parts with FRP reinforcement bars concern mostly investigations on bent elements (beams, slabs) [1, 2]. There are also available a few theoretical analyses on columns [3–5]. Though, there is still little experimental data concerning concrete columns with FRP bars [6–8], especially subjected to eccentric load, as also underlined in the review article [9]. This research aims to fulfill this research gap. Also, basalt FRP bars were chosen as relatively new type of non-metallic bars with low ecological impact [1].A total of eight columns with the height of either 750 mm or 1500 mm having 150 mm x 150 mm rectangular cross section were examined under axial or eccentric mechanical load up to 290 kN. Columns were reinforced with four BFRP main bars with the diameter of either 8 or 10 mm, and 8 mm steel stirrups in each case. The results on the thermal and mechanical properties’ investigations on BFRP bars were presented in [10]; the compressive strength values of the used BFRP bars were in the range of 441.2–466.8 MPa and elasticity modulus at compression values were equal to 31.0–38.4 GPa. Tested compressive strength of concrete, from which all columns were made (in one concrete pouring) were equal to 33.8 MPa. Each column was loaded in three cycles of loading-unloading, increasing the eccentricity, from 0 to 2 cm, and finally to 4 cm. DIC (Digital Image Correlation) method was used for the analysis of crack propagation (as in earlier research of bent elements [11]), but also unexpectedly there were visualised intensification areas of compression micro-damages. Failure was noted for two elements - B075_8_2 at the eccentricity of 4 cm (failure load – 290 kN after 60 s of sustained load) and B150_10_2 at the eccentricity of 4 cm (280 kN). Other specimens did not fail under load up to 290 kN. Maps from DIC method were also compared with results from numerical modelling (in Abaqus software) with good resemblance.
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Erbe, Christine, Alec Duncan, and Kathleen J. Vigness-Raposa. "Introduction to Sound Propagation Under Water." In Exploring Animal Behavior Through Sound: Volume 1. Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-97540-1_6.
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AbstractSound propagation under water is a complex process. Sound does not propagate along straight-line transmission paths. Rather, it reflects, refracts, and diffracts. It scatters off rough surfaces (such as the sea surface and the seafloor) and off reflectors within the water column (e.g., gas bubbles, fish swim bladders, and suspended particles). It is transmitted into the seafloor and partially lost from the water. It is converted into heat by exciting molecular vibrations. There are common misconceptions about sound propagation in water, such as “low-frequency sound does not propagate in shallow water,” “over hard seafloors, all sound is reflected, leading to cylindrical spreading,” and “over soft seafloors, sound propagates spherically.” This chapter aims to remove common misconceptions and empowers the reader to comprehend sound propagation phenomena in a range of environments and appreciate the limitations of widely used sound propagation models. The chapter begins by deriving the sonar equation for a number of scenarios, including animal acoustic communication, communication masking by noise, and acoustic surveying of animals. It introduces the concept of the layered ocean, presenting temperature, salinity, and resulting sound speed profiles. These are needed to develop the most common concepts of sound propagation under water: ray tracing and normal modes. This chapter explains Snell’s law, reflection and transmission coefficients, and Lloyd’s mirror. It provides an overview of publicly available sound propagation software (including wavenumber integration and parabolic equation models). It concludes with a few practical examples of modeling propagation loss for whale song and a seismic airgun array.
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Tavares, Vanessa, Cristina Sousa Coutinho Calheiros, Inês Burmester Martins, et al. "Modularity and Prefabrication." In Springer Tracts in Civil Engineering. Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-73490-8_8.
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AbstractThe concepts of “modularity” and “prefabrication” require a deeper understanding being crucial to investigate their relation with the circular economy. Prefabrication involves pre-manufacturing building elements off-site and their transport to the construction site and assembly. Prefabrication can be divided into different categories: Component, Non-volumetric, Volumetric, Modular construction, Hybrid structures, or Whole building prefabrication; and can be based on linear (e.g., columns or pillars), bidimensional (e.g., walls or floor panels), or tri-dimensional elements (e.g., modules or whole prefabricated houses). The most commonly used materials are steel, wood, and concrete, although plastic, composite, and nature-based materials are increasingly being explored. While comparing the prefabricated materials, steel has high embodied impacts but recycle and reuse potential, timber has biogenic content and high reuse potential, and concrete poses transport and assembly challenges. The refurbishment of prefabricated buildings and the use of prefabricated elements in refurbishment are also discussed. The main benefits of adopting prefabrication are impact, cost, material, waste, and time reduction, with quality increase; and the challenges are cultural, technical, and market aspects with some investment required. A bibliometric analysis explores the relationship between modularity, prefabrication, and circular construction and concludes that the link between the three concepts seems fragile and unclear.
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Tausch, Arno. "“Political Islam”—A Contested Term." In Political Islam and Religiously Motivated Political Extremism. Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-24854-2_2.
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AbstractThis chapter shows that there is a very broad consensus in research in the leading peer-reviewed journals of the social sciences and in the publications of the world’s leading book publishers to work with the concept of “political Islam”, whereby this analytical-conceptual consensus also includes those who, such as former US President Barack Obama, in his famous Presidential Study Directive No 11, even see an opportunity for cooperation with political Islam, which rejects terrorism, or the French sociologist Francois Burgat, who aggressively argues for an alliance of political Islam with the political left of the West. Important research figures in international Middle East studies, such as Francois Burgat, but also Jocelyne Cesari, John Esposito, Gilles Kepel, Oliver Roy, all of them, and for all the differences they may have in their approach to the phenomenon, have all written important texts on political Islam. We strongly oppose the fact that the Federal Agency for Civic Education (Bundeszentrale für politische Bildung), which is subordinate to the German Ministry of the Interior, writes that whoever uses this term is engaging in “alarmist thinking, placing Muslims under a “general suspicion”, fishing in the right-wing pond of voters, and using a term that has incitement potential”. This view, expressed by the Federal Agency for Civic Education in Bonn in the language that is so common in Europe today and that covers large sections of the academic community and the opinion columns of the major daily newspapers, seems to be becoming more and more popular.
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Hardebusch, Björn, Julia Polley, Benjamin Dambacher, Karin Kypke, and Ralf Lippold. "Analysis and Quality Control of WHO- and UNEP-Coordinated Human Milk Studies 2000–2019: Organochlorine Pesticides and Industrial Contaminants." In Persistent Organic Pollutants in Human Milk. Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-34087-1_5.
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AbstractThe analytical method for determination of nonpolar organochlorine pesticides and industrial contaminants in human milk comprises extraction of lipids, the use of three internal standards, two chromatographic separation steps for clean-up and gas chromatography on various columns of different polarity and different detectors (GC-ECD, GC-MS/MS). The more polar analytes were determined applying the QuEChERS method and HPLC-MS/MS measurement.As accredited laboratory since 1998, a comprehensive quality control programme was applied to prove the long-term reliability of results of the WHO/UNEP-coordinated surveys on human milk performed between 2000 and 2019. The concept comprised numerous quality control samples (spiked samples for quality control charts and left-over samples from proficiency tests as in-house reference material) and participation in 53 proficiency tests covering test samples of food of animal origin, plant oils and standard solutions. Trueness calculated from the spiked quality control samples and expressed as median recovery for 29 analytes was 99% (range 86%–110%), and the precision expressed as the median of the coefficient of variation (CV) was 12% (range 0.7%–31%). Trueness calculated from in-house reference material (375 results for 41 consensus values) was on average 96% with a precision expressed as CV of 7.6%. Finally, the results of 53 proficiency tests were used to derive trueness for 23 analytes as deviation from the assigned value; this deviation was on average 14% (range 6%–27%). As conclusion of various approaches of analytical quality control, for the 2000–2019 period the long-term trueness was on average in the range 85%–95% with a precision on average better than 15%.The general criteria for the operation of testing laboratories as laid down in EN ISO/IEC 17025, the analytical criteria for analyses of organochlorine pesticides and industrial contaminants in feed and food required by EU legislation and the criteria for monitoring information for the Parties to the Stockholm Convention were met.
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Chaudhary, Bedansh Roy, and Shiong Wen Low. "Thoracic and lumbar spine injuries." In Oxford Textbook of Neurological Surgery, edited by Ramez W. Kirollos, Adel Helmy, Simon Thomson, and Peter J. A. Hutchinson. Oxford University Press, 2019. http://dx.doi.org/10.1093/med/9780198746706.003.0069.
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Trauma to the thoracic and lumbar spine may be classified using the Magerl’s or Thoracolumbar Injury Classification and Severity Score (TLICS) classifications. Older thoracolumbar trauma classification systems include those of Holdsworth, which emphasizes the mechanism of injury; Whitesides, which defines the two-column concept being analogous to a construction crane; Punjabi and White, who developed stability scoring systems; and Denis with a mechanistic classification based on instability pertaining to three columns of the spine. Management may be conservative with analgesia and bracing or surgical with posterior, transthoracic, or circumferential spinal fusion. In this chapter the classification of these injuries and their management will be discussed. The techniques to insert pedicle screws and the role of minimally invasive techniques will be explained.
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West, M. L. "Wind and Percussion." In Ancient Greek Music. Oxford University PressOxford, 1992. http://dx.doi.org/10.1093/oso/9780198148975.003.0005.
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Abstract Wind instruments-at any rate, those that chiefly concern us-work by setting up vibrations in air that is enclosed in a pipe or pipes. You cannot achieve this simply by blowing into the pipe. There are essentially three things you can do. You can blow sideways across the air column-across the end of the pipe, or across a hole in its side. This is the principle of the flute. Or you can blow down the pipe with your mouth shut. The breath bursting out sets your lips vibrating against each other, and these vibrations are imparted to the air column. This is the principle of the trumpet and the horn. Or you can have a mouthpiece containing a vibrating reed that sets the air going. This is the principle of the clarinet and the oboe.
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Chrysafi Adi Konstantina and Virvou Maria. "Using Fuzzy Cognitive Maps for the Domain Knowledge Representation of an Adaptive e-Learning System." In Frontiers in Artificial Intelligence and Applications. IOS Press, 2012. https://doi.org/10.3233/978-1-61499-094-9-257.
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In this paper we describe a method for the knowledge representation of an e-learning adaptive system. A crucial factor for adaptive systems is to provide adaptive navigation support through the links that constitute the learning material. Therefore, the system should advice each individual learner which domain concepts to read, taking into account her/his progress and performance on other related domain concepts. As a result, the system should be informed about the knowledge dependencies that exist among the domain concepts of the learning material, as well as the strength on impact of each domain concept on others. Fuzzy Cognitive Maps (FCMs) seem to be an ideal way for representing graphically this kind of information. However, due to the fact that a FCM usually is complex and there is a difficulty in extracting information of them, we suggest transforming them to a two-dimensional matrix, in which knowledge dependencies are analysed clearly through its rows and columns.
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Magnússon, Gunnlaugur. "”… och det är sakens kärna”. Om kvalitativa innehållsanalyser." In Hvordan studere utdanningspolitikk? Tekster, teorier, tilnærminger. Cappelen Damm Akademisk/NOASP, 2024. http://dx.doi.org/10.23865/noasp.215.ch4.
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The purpose of this chapter is to introduce qualitative content analysis as a methodological tool in education research. The chapter will initially briefly describe the basics of the method and then give more concrete descriptions of different approaches within it. The rest of the chapter will be dedicated to three different examples of my own use of qualitative content analysis in empirical research. The first example deals with empirically based and inductively driven content analysis in which searches for patterns and themes were made in extensive and unstructured empirical material, consisting of hundreds of free text responses to a questionnaire. Theoretical concepts were then used to explain the outcome of the analysis. The second example is theory-driven, critical analysis in which several policy texts, both public investigations and parliamentary proposals, were analyzed using concepts from curriculum theory. Here, the material was approached with specific concepts that help to both continuously structure the reading and explain the results. The third example is based on Koselleck’s (1985) diachronic analysis in a historical review of a concept in an extensive text material from media, mainly columns, editorials and debate articles. Here, theoretical concepts of conspiracy theories were used to retrospectively explain the concept’s use, function, and rationality. In conclusion, I briefly summarize the differences and similarities of the different approaches, and draw a couple of conclusions about their scientific advantages and disadvantages. Finally, a discussion follows about how the method can be applied to different kinds of policy texts, in particular for comparative purposes.
Conference papers on the topic "Three column concept"
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Choi, Hyeongjin, Dave M. Osabel, Sanghoon Kim, Jaehoon Bae, Youngju Kim, and Jaehyeok Doh. "Improvement Study of the Proposed Beam-Column Carbon Minimized Dismantle Connection (CNDC) using Three-Dimensional Finite Element Analysis." In IABSE Symposium, Tokyo 2025: Environmentally Friendly Technologies and Structures: Focusing on Sustainable Approaches. International Association for Bridge and Structural Engineering (IABSE), 2025. https://doi.org/10.2749/tokyo.2025.3044.
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<p>An innovative concept design of a “carbon-neutral, easy-to-dismantle beam-column connection” was previously proposed for an environmentally friendly construction. Full-scale test and three-di- mensional finite element (3D-FE) analysis had been conducted to investigate how the so-called Carbon Minimized Dismantle Connection (CNDC) would behave. Accordingly, the CNDC met the stiffness for the rotation angle of moment frame similarly as a conventional beam-column connec- tion. However, in terms of energy dissipation, it showed relatively low performance due to pinching of moment-rotation hysteresis. Numerical modeling showed local bulging-and-dimpling of column face due to the pulling of shear tab by the beam. Hence, an improvement study on the design and configuration of the CNDC by 3D-FE analysis was carried out. Numerically, the new design of the CNDC with the added fillet plate and increased column thickness has a better performance than the originally proposed design<b>.</b></p>
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Sakata, Mikihiro, Tomoaki Kiso, and Kunio Ishii. "A Review of the Development of 13-17% Cr Stainless Steel Filler Metals and Filler Metal Selection for Restoring 13% Cr Stainless Steel Cladding." In CORROSION 2019. NACE International, 2019. https://doi.org/10.5006/c2019-12754.
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Abstract Materials clad with 13% Cr stainless steel have been widely used in refining equipment where high temperature sulfidation is a concern. When such materials are applied in columns, vessels, and heat exchangers, restoration of the cladding using weld overlay is required to bridge over carbon steel or low alloy steel base metal weld seams between the cladding materials during original fabrication or for welding repairs made during service. The first part of this paper describes a comprehensive review of the use of 13-17% Cr stainless steel nearly matching filler metals for restoring the cladding in Japan since the 1960's. The review focuses mainly on how the Japanese industry has improved the weldability of the near matching filler metals and overcome cracking problems in the first layer of the cladding restoration welds. The last half of this paper discusses three possible choices of filler metal for restoring 13% Cr stainless steel cladding: Type 309/309L stainless steel filler metal, Ni-based alloy filler metal, and 13-17% Cr stainless steel nearly matching filler metals. The pros and cons of these filler metals are discussed from the viewpoints of fabrication and corrosion resistance in the service environment.
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Williams, Neil, Homayoun Heidari, and Sean Large. "Three-Column TLP Concept for Marginal Field Development." In ASME 2009 28th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/omae2009-80170.
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This paper discusses the development of a new self-stable TLP concept for marginal field applications. This concept — called ThreeStar™ — is based on three rectangular columns arranged at the vertices of an equilateral triangle and battered towards its geometric center. The columns are joined by conventional rectangular pontoons. The reduced number of tendons/piles relative to a conventional four column TLP makes the ThreeStar a cost-effective solution in applications where the production riser count is relatively low or the topsides payload is small. This paper presents a description of the technical development of the ThreeStar TLP and outlines the unique features of the concept. The relative merits of the ThreeStar over comparable four-column TLPs for different environments and payload ranges are discussed. Finally, ThreeStar systems are presented for two example deepwater applications.
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Chou, Frank, John Chianis, and Xinyu Zhang. "Self-Installed Single Column Floater." In ASME 2004 23rd International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2004. http://dx.doi.org/10.1115/omae2004-51466.
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This paper introduces a novel floating production platform concept for exploration and production of oil and gas in ultra deep water. The developmental effort has been supported by ABB in-house research and development budget. This novel production unit is an enhanced version of ABB Self-Installed Single Column Floater (SISCF) concept. This unit is envisioned to be completely assembled at quayside, towed to location, and be installed vertically to its target draft without the need of a major crane vessel. This enhanced feature reduces the wind load on the deck and hull significantly during wet tow as well as alleviates the uncertainty on the duration of an offshore operation, thereby widens the weather window for installation, hook-up and commissioning offshore. The enhanced SISCF (ESISCF) hull consists of four major components i.e., hard tank with center opening, soft tank with telescoping truss members and opening, permanent-stability ring, and three (3) telescoping support columns. During the installation phase, the telescoping columns are used to guide the permanent-stability ring, which provided needed stability in the installation phase. In addition, because of the way center truss being constructed, the hard tank is collapsed (or sit) right on top of the soft tank during wet tow thus reduced the wind arm (almost 100 ft) and wind forces. In its in-place position, ESISCF motion responses in waves are found to be excellent because of its deep draft. The current concept combines the advantages of a spar and a semi-submersible vessel. The paper will detail the concept, and outline the fabrication to installation scenario. The principal dimensions of a typical ESISCF for a given payload will be presented together with its stability and motion responses in waves based on the sea conditions representing a typical geographical area of Gulf of Mexico. The advantages of this concept will be explained in detail.
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Socrates S., Sandana, Sriram Venkatachalam, and Sundar V. "Hydrodynamic Performance of Three Different Oscillating Water Column Devices in Regular Waves." In ASME 2023 42nd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2023. http://dx.doi.org/10.1115/omae2023-108074.
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Abstract The concept of oscillating water column (OWC) integrating with coastal structures is popular in marine engineering to extract energy from the ocean. The objective of the study is to numerically examine the newly proposed three different fixed oscillating water columns with a forward duct at the bottom of OWC named Forward Duct OWC (FD-OWC), a curved wall at the front side of OWC with a radius equal to the height of OWC called as Curved Front Lip Wall OWC (CFLW-OWC), and hybridization of the curved and vertical wall at the front portion of OWC named as Curved Vertical Front Lip Wall (CVFLW-OWC). This paper used a three-dimensional numerical model to investigate the hydrodynamic performance of three OWC devices under regular waves for constant wave steepness. The numerical model is based on the open-source computational fluid dynamics package OpenFOAM. The numerical results are validated with the available experimental results. The influence of the wave amplification factor, wave power absorption coefficient, the air pressure inside the three OWC chambers, hydrodynamic efficiency, and dynamic water pressure inside and outside the three OWC chambers are evaluated. The results show that the CVFLW-OWC exhibits better hydrodynamic efficiency.
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Mertz, Lawrence. "Concept for a solid-state imaging photon counter." In OSA Annual Meeting. Optica Publishing Group, 1988. http://dx.doi.org/10.1364/oam.1988.thaa7.
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Consider a crosspoint array of thyristors. Initially all are off, and then one thyristor is turned on to give conduction from one row to one column. A peripheral array of diodes serves to encode just which row and column are conducting. The power may then be interrupted briefly to reset the thyristors. It is proposed that the thyristors be designed as avalanche photothyristors and that the device be moderately cooled and operated somewhat over the avalanche breakdown voltage as recommended by Ekstrom1 for activation by individual photons. The result of obtaining photon positions is an imaging photon counter that should have three basic advantages over a CCD at extremely low light levels: lower background because of no readout noise; higher pictorial speed because of no raster scanning; and preservation of temporal sequence information for a posteriori dynamic image processing.
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Krishnan, Rajeswari, and Nallayarasu Seeninaidu. "Hydrodynamic Response of Three Column Semi-Submersible Floater Supporting Vertical Axis Wind Turbine." In ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/omae2017-62452.
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Offshore wind energy extraction has gathered momentum around the world due to its advantages over onshore wind farms at various fronts. The floating support system with vertical axis wind turbine might prove to be feasible concept in medium to deep waters. In this context, this paper addresses an investigation of hydrodynamic analysis of three column semi-submersible with Vertical Axis Wind Turbine (VAWT) in parked condition under regular and random waves. Free decay experiments were conducted for using scale model (1:75) in a laboratory wave basin at the Department of Ocean Engineering in Indian Institute of Technology Madras, India. Computational Fluid Dynamics (CFD) simulations were used to assess damping characteristics and validated with the experiments. Numerical simulations of hydrodynamic motion response of the floater were carried out using potential flow theory based commercial software (ANSYS AQWA). The damping values obtained from experiments were used in numerical simulations to obtain motion response and Response Amplitude Operator (RAO). The motion response obtained from the study was used to verify the suitability of the system for deployment in east and west coast of India.
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Jaculli, Marcelo Anunciação, Savin Viswanathan, Christian Holden, Bernt Johan Leira, and Sigbjørn Sangesland. "Numerical Modeling of a Motion-Neutralized Floater Concept for Maritime Operations." In ASME 2024 43rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2024. http://dx.doi.org/10.1115/omae2024-126339.
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Abstract For continuous operation in harsh sea conditions, such as those seen in the North and Norwegian seas during the winter season, a floater must demonstrate reduced amplitudes of motion. A concept of a motion-compensations mechanism has been proposed that can cancel, or at least diminish, the level of such motions. In this context, a three-column asymmetric semisubmersible floater with passive motion-control technology, dubbed “Sakayan”, is discussed. This new floater concept can be used for offshore wind power generation, as well as for well interventions. Passive control is performed through the usage of air chambers, which are placed inside each of its three columns. This is a continuation of previous research efforts to investigate the effectiveness of air chambers to compensate for heave motion. This work aims to further study the dynamics of this floater and verify its capability to ameliorate the heave and pitch/roll motions. Numerical simulations are carried out using commercial software in the frequency and time domains. Results show that the presence of air chambers reduces the amplitude of motion for most of the six degrees of freedom and wave/wind incidence angles, albeit complete elimination is not achieved. Further studies are necessary concerning the application of an active control system for the present floater concept.
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Yoshida, Hisafumi, Keiichi Yamasaki, and Shunji Sunahara. "Application of Wave Devouring Propulsion Technology to Support Positioning of Floating Structure." In ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/omae2018-77143.
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It becomes one of the key issues to reduce capacity of generators for the dynamic positioning (DP) system on offshore structures for the reduction of Green House Gas emission. For the purpose, to decrease environmental forces, wave, wind and current forces, are very important for the DP system design. One of the concepts to reduce wave forces is the “wave devouring propulsion technology” (WDPT) installed vessels. WDPT employs wings attached to the vessel and they produce thrust in waves as a propulsor of vessel. WDPT concept seems to be applicable for offshore structures. In this paper, application of WDPT for three-column type offshore structure is experimentally investigated. Flat plate type wings are installed between columns, and vertical position of wings, frequency response of thrusts in waves and directional particulars of wave incident angle are studied.
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Wang, Shuaishuai, and Torgeir Moan. "Initial Global Design for Three-Column Semi-Submersible Hulls of a 15-MW Floating Wind Turbine." In ASME 2023 5th International Offshore Wind Technical Conference. American Society of Mechanical Engineers, 2023. http://dx.doi.org/10.1115/iowtc2023-119504.
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Abstract Support structure design of floating wind turbines (FWTs) is an iterative process, which can be accomplished into three phases, named 1) selecting of floater type (barge, semi, spar, TLP, etc.); 2) determining global dimensions for a given floater type; 3) determining scantlings of the floater based on detailed design. This study deals with the design phase 2), namely initial global design, for a three-column semi-submersible hull for a 15-MW FWT. An efficient and effective methodology, which was developed by authors in a previous study and successfully used for the global design of a 10-MW semi-submersible floater, is used in this case study. The initial global design criteria include simplified serviceability criteria related to the power performance as well as safety criteria in terms of intact stability and indirect global strength criteria through requirements to natural frequencies of rigid-body motions. First, a sensitivity study will be conducted to various design variables of the floater, including draft, column centerline spacing, outer column radius, outer pontoon radius, pontoon width and pontoon height. Based on the sensitivity study, important global design parameters are recognized for the floater, which facilitates the determination of initial design options. Subsequently, the intact stability analysis is performed for the selected design options for different wind directions. Critical load directions of the floater will be identified. In addition, the influence of deck beam dimensions and freeboard on intact stability is investigated. Finally, the global layouts of the floater are assessed based on global design criteria. This study provides new insights into the quasi-static or/and dynamic behavior of the promising FWT concept, which is essential to achieve serviceability and safety. In addition, it provides a basis for carrying out the detailed design to determine the scantlings in the third design phase.
Reports on the topic "Three column concept"
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Hodul, M., H. P. White, and A. Knudby. A report on water quality monitoring in Quesnel Lake, British Columbia, subsequent to the Mount Polley tailings dam spill, using optical satellite imagery. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/330556.
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In the early morning on the 4th of August 2014, a tailings dam near Quesnel, BC burst, spilling approximately 25 million m3 of runoff containing heavy metal elements into nearby Quesnel Lake (Byrne et al. 2018). The runoff slurry, which included lead, arsenic, selenium, and vanadium spilled through Hazeltine Creek, scouring its banks and picking up till and forest cover on the way, and ultimately ended up in Quesnel Lake, whose water level rose by 1.5 m as a result. While the introduction of heavy metals into Quesnel Lake was of environmental concern, the additional till and forest cover scoured from the banks of Hazeltine Creek added to the lake has also been of concern to salmon spawning grounds. Immediate repercussions of the spill involved the damage of sensitive environments along the banks and on the lake bed, the closing of the seasonal salmon fishery in the lake, and a change in the microbial composition of the lake bed (Hatam et al. 2019). In addition, there appears to be a seasonal resuspension of the tailings sediment due to thermal cycling of the water and surface winds (Hamilton et al. 2020). While the water quality of Quesnel Lake continues to be monitored for the tailings sediments, primarily by members at the Quesnel River Research Centre, the sample-and-test methods of water quality testing used, while highly accurate, are expensive to undertake, and not spatially exhaustive. The use of remote sensing techniques, though not as accurate as lab testing, allows for the relatively fast creation of expansive water quality maps using sensors mounted on boats, planes, and satellites (Ritchie et al. 2003). The most common method for the remote sensing of surface water quality is through the use of a physics-based semianalytical model which simulates light passing through a water column with a given set of Inherent Optical Properties (IOPs), developed by Lee et al. (1998) and commonly referred to as a Radiative Transfer Model (RTM). The RTM forward-models a wide range of water-leaving spectral signatures based on IOPs determined by a mix of water constituents, including natural materials and pollutants. Remote sensing imagery is then used to invert the model by finding the modelled water spectrum which most closely resembles that seen in the imagery (Brando et al 2009). This project set out to develop an RTM water quality model to monitor the water quality in Quesnel Lake, allowing for the entire surface of the lake to be mapped at once, in an effort to easily determine the timing and extent of resuspension events, as well as potentially investigate greening events reported by locals. The project intended to use a combination of multispectral imagery (Landsat-8 and Sentinel-2), as well as hyperspectral imagery (DESIS), combined with field calibration/validation of the resulting models. The project began in the Autumn before the COVID pandemic, with plans to undertake a comprehensive fieldwork campaign to gather model calibration data in the summer of 2020. Since a province-wide travel shutdown and social distancing procedures made it difficult to carry out water quality surveying in a small boat, an insufficient amount of fieldwork was conducted to suit the needs of the project. Thus, the project has been put on hold, and the primary researcher has moved to a different project. This document stands as a report on all of the work conducted up to April 2021, intended largely as an instructional document for researchers who may wish to continue the work once fieldwork may freely and safely resume. This research was undertaken at the University of Ottawa, with supporting funding provided by the Earth Observations for Cumulative Effects (EO4CE) Program Work Package 10b: Site Monitoring and Remediation, Canada Centre for Remote Sensing, through the Natural Resources Canada Research Affiliate Program (RAP).
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STUDY ON THE ULTIMATE SHEAR PERFORMANCE OF CONCRET- FILLED STEEL TUBULAR COMPOSITE COLUMNS. The Hong Kong Institute of Steel Construction, 2024. http://dx.doi.org/10.18057/ijasc.2024.20.3.3.
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The shear performance of three concrete-filled steel tubular (CFST) composite columns was investigated via single-point shear tests, considering shear-span ratios of 0.75, 1, and 1.5. The findings indicated that the failure mode of the CFST composite column transitioned from oblique compression shear failure to localized shear failure in the joint areas as shear-span ratio decreased. An extended analysis of the parameters was carried out utilizing the ABAQUS finite element model. The analysis indicates that the ultimate shear resistance capability of steel-concrete composite columns increases with the rise in the strength of the batten concrete, the batten concrete thickness-to-span ratio, and the outer diameter of column limbs. However, it decreases with an increase in shear-span ratio. The accuracy of the calculation methods for existing similar structures was assessed, and based on the force transmission mechanism of CFST composite columns, theoretical and simplified calculation methods were proposed that meet engineering precision requirements. Consequently, this method offers a valuable theoretical reference for engineering applications.