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Journal articles on the topic "2D+C (Program)"
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Hadjipavlou-Litina, Dimitra, and Aikaterini Peperidou. "Exploring Cinnamic Acid Multitarget Hybrids in Terms of 2D-QSAR." International Journal of Quantitative Structure-Property Relationships 4, no. 3 (July 2019): 34–98. http://dx.doi.org/10.4018/ijqspr.2019070103.
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Cinnamic acids hybrids present a variety of significant biological activities and are characterized as pleiotropic agents. The 2D- QSAR analysis presented here attempts to identify the structural features and physicochemical properties of cinnamic acids hybrids presenting: a) antitumor activity; b) immunosuppressive activity; c) inhibitory activity on various enzymes; d) antioxidant activity. A 2D-QSAR analysis was carried out for 26 data sets of compounds taken from the literature using the C-QSAR program of Biobyte. In 5 cases hydrophobicity appeared to be important. Steric factors in the form of overall molar refractivity (CMR), molar refractivity of the substituents (MR), molar volume (MgVol) and the Verloop Sterimol parameters have a significant impact on the biological activity whereas electronic parameters as Hammett σp, σm, σo or Σσ appear in most of the cases. The anticancer as well as anti-inflammatory and antioxidant activities of caffeic acid hybrids are governed by lipophilicity, electron and stereochemical factors.
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Prabhakar Rao, K., and G. Ashok Babu. "EMOD2D—a program in C++ for finite difference modelling of magnetotelluric TM mode responses over 2D earth." Computers & Geosciences 32, no. 9 (November 2006): 1499–511. http://dx.doi.org/10.1016/j.cageo.2006.02.017.
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Pan, Ya-Ru, Xiu-Mei Li, Jian-Ye Ji, and Qing-Wei Wang. "Synthesis, Crystal Structure, and Theoretical Calculations of Two Cobalt, Nickel Coordination Polymers with 5-Nitroisophthalic Acid and Bis(imidazol) Ligands." Australian Journal of Chemistry 69, no. 11 (2016): 1296. http://dx.doi.org/10.1071/ch16110.
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Two new complexes [Co(NIPH)(bimb)(H2O)]n (1) and [Ni(NIPH)(mbix)]n (2) (H2NIPH = 5-nitroisophthalic acid, bimb = 1,4-bis(imidazol-1-yl)butane, mbix = 1,3-bis(imidazol-1-ylmethyl)benzene) have been hydrothermally synthesised and structurally characterised by elemental analysis, IR spectroscopy, thermogravimetric analysis, UV spectroscopy, and single-crystal X-ray diffraction. Complex 1 exhibits a two-dimensional (2D) network, which was stabilised through O–H···O and C–H···O hydrogen-bonding interactions. Complex 2 shows a two-dimensional (2D) network structure, which was further extended into a three-dimensional supramolecular structure through C–H···O hydrogen bonds and π–π interactions. Moreover, we analysed the natural bond orbital (NBO) using the PBE0/LANL2DZ method in the Gaussian 03 program. The calculation results indicated the obvious covalent interactions between the coordinated atoms and the CoII or NiII ion.
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Sofjan, Hendy, Jeanny Pragantha, and Darius Andana Haris. "PEMBUATAN GAME 2D VIRTUAL PET “BARCOMON” DENGAN FITUR BARCODE SCANNER." Jurnal Ilmu Komputer dan Sistem Informasi 8, no. 2 (August 5, 2020): 241. http://dx.doi.org/10.24912/jiksi.v8i2.11529.
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“Barcomon” is a virtual pet game for smartphone with an Android Operating System. This game was made using C# programming language and Unity as the development program. In this game, player will act as a Coder with a goal to achieve the Code Master title by winning all the battle on The Forum. Coder must take care and train the monsters. Player can get the monsters by scanning any barcode from any daily product. The testing of this game is done by using a blackbox testing method, alpha testing, and beta testing with a survey distributed to 39 respondents. The survey shows that Barcomon is a game with an interesting gameplay, easy to play, and has a unique barcode scanning feature that is rarely found in other games.
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Gordillo, Geovanny, Mario Morales-Hernández, I. Echeverribar, Javier Fernández-Pato, and Pilar García-Navarro. "A GPU-based 2D shallow water quality model." Journal of Hydroinformatics 22, no. 5 (July 8, 2020): 1182–97. http://dx.doi.org/10.2166/hydro.2020.030.
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Abstract In this study, a 2D shallow water flow solver integrated with a water quality model is presented. The interaction between the main water quality constituents included is based on the Water Quality Analysis Simulation Program. Efficiency is achieved by computing with a combination of a Central Processing Unit (CPU) and a Graphics Processing Unit (GPU) device. This technique is intended to provide robust and accurate simulations with high computation speedups with respect to a single-core CPU in real events. The proposed numerical model is evaluated in cases that include the transport and reaction of water quality components over irregular bed topography and dry–wet fronts, verifying that the numerical solution in these situations conserves the required properties (C-property and positivity). The model can operate in any steady or unsteady form allowing an efficient assessment of the environmental impact of water flows. The field data from an unsteady river reach test case are used to show that the model is capable of predicting the measured temporal distribution of dissolved oxygen and water temperature, proving the robustness and computational efficiency of the model, even in the presence of noisy signals such as wind speed.
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Bielecki, Włodzimierz, and Piotr Błaszyński. "Parallel Tiled Code for Computing General Linear Recurrence Equations." Electronics 10, no. 17 (August 25, 2021): 2050. http://dx.doi.org/10.3390/electronics10172050.
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In this article, we present a technique that allows us to generate parallel tiled code to calculate general linear recursion equations (GLRE). That code deals with multidimensional data and it is computing-intensive. We demonstrate that data dependencies available in an original code computing GLREs do not allow us to generate any parallel code because there is only one solution to the time partition constraints built for that program. We show how to transform the original code to another one that exposes dependencies such that there are two linear distinct solutions to the time partition restrictions derived from these dependencies. This allows us to generate parallel 2D tiled code computing GLREs. The wavefront technique is used to achieve parallelism, and the generated code conforms to the OpenMP C/C++ standard. The experiments that we conducted with the resulting parallel 2D tiled code show that this code is much more efficient than the original serial code computing GLREs. Code performance improvement is achieved by allowing parallelism and better locality of the target code.
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Li, Xiao-Hong, and Xian-Zhou Zhang. "The spectroscopic NMR analysis of 2-dicyanovinyl-5-phenylthiophene by the density functional method." Canadian Journal of Chemistry 91, no. 6 (June 2013): 375–81. http://dx.doi.org/10.1139/cjc-2012-0482.
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Quantum chemistry calculations have been performed by using the Gaussian03 program to compute the optimized geometry and harmonic vibrational frequency of 2-dicyanovinyl-5-phenylthiophene (C14H8N2S) in the ground state. Atomic charges at B3LYP/6-311++G(d,p) level are also calculated. Potential energy distributions (PEDs) using MOLVIB program are also used to interpret the theoretical vibrational spectra of the title compound. A detailed interpretation of the infrared spectra of the title compound is reported. The theoretical spectrograms for the IR spectra of the title compound have been constructed. The crystal structure obtained by molecular mechanics belongs to the P21 space group, with lattice parameters Z = 2, a = 6.6745 Å, b = 14.7672 Å, c = 11.0986 Å, ρ = 0.921 g cm–3. In addition, the 13C and 1H NMR are further investigated by the B3LYP/6-311++G(d,p) and B3LYP/6-311++G(2d,2p) methods.
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She, Chen Hua, Jian Yu Lin, and Shen Yung Lin. "Numerical Control Programming System for Mill-Turn Machining." Applied Mechanics and Materials 799-800 (October 2015): 1154–57. http://dx.doi.org/10.4028/www.scientific.net/amm.799-800.1154.
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To develop the numerical control program of mill-turn machine, the traditional method is to apply the computer-aided design and manufacture software to construct the geometric model, then to generate tool path and convert the path to NC program. For complex numerical control program of mill-turn machine, such as the multiple turret synchronized motion machining, because of the need to control time sequence, the NC program is highly required on using of dedicated software system. The objective of this paper is to establish a mill-turn machining system with window interface of via the language of Borland C++ Builder. The developed system can plan the machining path of simple mill-turn features, including turning shape, axial slot milling, and radial packet milling, and generate the corresponding NC program. For the milling functions, after the offset coordinates are calculated along the polygonal angle vector in the center point of cutters, the NC program is generated. For the turning functions, through importing the 2D DXF (Drawing Exchange Format) file and inputting related configurations, the entity coordinates can be retrieved and the corresponding NC program is then converted. By means of the solid cutting simulation software and practical cutting experiment for the generated numerical control program, the accuracy of the tool path generation algorithm is confirmed. Hence, the cost of purchasing commercial software can be saved and the time of generating program can also be decreased so that the working efficiency can be enhanced.
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Manуuk, Oleksandr, and Yaroslav Sokolovskyy. "Development of Algorithm and Data Structure for 2D Regions Discrete Model Elements Accelerated Search." Computer Design Systems. Theory and Practice 6, no. 1 (2024): 79–93. http://dx.doi.org/10.23939/cds2024.01.079.
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This paper is devoted to improving the search request processing productivity for planar discrete models used in engineering software. A data structure has been developed to accelerate the search for discretization elements based on a hierarchical triangular mesh. The developed indexing structure is built by a downward iterative algorithm, which constructs each new level of the hierarchy based on the previous level or indexed triangulation by simplifying it, which ensures that the morphology of the triangulation mesh is preserved throughout all levels of the hierarchical indexing structure. The developed building algorithm ensures the presence of tree-like connections between the levels of the hierarchical triangulation mesh, which allows downward navigation between geometrically close triangles. Search acceleration is achieved by performing a directed search in the top level of the indexing structure and then navigating between levels using downward links until the indexed triangle is found. The program implementation was carried out using C++17, and visualization of triangulation grids and isolines was carried out using the ObjectARX library. Based on the software implementation, an executive library was created.
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Edy Soesanto, Aly Rasyid, and Hadi Suyanto. "Perencanaan Desain Offshore Kontruksi Bawah Laut menggunakan Pengolahan Data Pemodelan Geofisika dengan Program Simulasi 3D Surfer." JURNAL BHARA PETRO ENERGI 1, no. 2 (July 26, 2022): 37–46. http://dx.doi.org/10.31599/bpe.v1i2.1447.
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Abstract
Underwater construction design planning is increasingly being developed as a 3D modeling simulation, because 3D simulation is expected to be able to make the initial plan for making a design framework. Surfer is one of the software that was created for the purpose of making contour maps and three-dimensional modeling based on existing grids and simplifying and accelerating data conversion activities into the form of contour maps and surface plots. One of the applications is Surfer in the field of Underwater Technology development is 3D modeling simulation and bathymetric contour map making, sediment layer modeling using SBP data and making current stick plots to determine circulation and current velocity and direction. In addition, Surfer can also display maps in 2D or 3D. on this occasion Surfer 16 software will be used to process marine acoustic data with X (Easting) data, Y (Northing) data and six Z layer depths, namely Z1-Z6, the data is processed in one step to make 2D and 3D models which are then will be interpreted as a simulation material for the initial planning of the underwater construction design.
Keywords: design, offshore, construction, underwater, surfer
Abstrak
Perencanaan desain kontruksi bawah laut semakain banyak dikembangkan sebagai simulasi pemodelan 3D, karena simulasi 3D diharapkan dapat menjadikan rencana awal pembuatan kerangka desain. Surfer adalah salah satu dari perangkat lunak yang diciptakan untuk kegunaan pembuatan peta kontur dan pemodelan tiga dimensi yang berdasarkan grid yang ada dan mempermudah serta mempercepat akvitas konversi data ke dalam bentuk peta kontur dan plot permukaan. Salah satu aplikasi adalah Surfer dalam bidang pengembangan Teknologi Bawah laut adalah simulasi pemodelan 3D dan pembuatan peta kontur batimetri, pemodelan lapisan sedimen melalui data SBP dan pembuatan stick plot arus untuk mengetahui sirkulasi dan kecepatan dan arah arus. Selain itu, Surfer juga dapat menampilkan peta secara 2D ataupun 3D. pada kesempatan ini software Surfer 16 yang akan digunakan unutk mengolah data akustik kelautan dengan data X (Easting) ,data Y (Northing) dan enam kedalaman lapisan Z yaitu Z1-Z6, data tersebut diproses dengan sebuah tahapan untuk menjadikan model 2D dan 3D yang selanjutnya akan di interpretasi sebagai bahan simulasi perencanaan awal desain kontruksi bawah laut.
Kata kunci: desain, offshore, kuntruksi, bawah laut, surfer
Reference:
Septina Anggiani. Pengolahan data oseanografi dengan surfer 10.0 dan odv 4.0 Surya, Yohanes Sam. 2008. Surfer8.http://www.gis4u.net [26 November2013]
International Hydrographic Organization (IHO) Standard for Hydrographic Surveys, Special Publication No.44 (SP.44), 5th Edition, February 2008
Alba, J. L. and Audibert, J. M. E. (1999). “Pile design in calcareous and carbonaceous granular materials: a historical overview”, Second International Conference Engineering on for Calcareous Sediments, Bahrain
American Petroleum Institute (2000). “Recommended practice for planning, designing, and constructing fixed offshore platforms-working stress design”, API Recommended Practice 2A-WSD (RP 2A-WSD), (21’‘ ed.). API, Washington, D.C
Anderson, D. G. and Stokoe, K. H. (1978). “Shear modulus: a time-dependent soil property”, Dynamic Geotechnical Testing, ASTM STP 654, American Society for Testing and Materials, pp. 66-90.
Angemeer, J., Carlson, E. D., and Klick, J. H. (1973). “Techniques and results of offshore pile load testing in calcareous soils”, Proceedings, Ffth Offshore Technology Conference, Houston, Vol. 2, pp. 677-692
Bogard, J. D. and Matlock, H. (1990). “Application of model pile tests to axial pile design”, Proceedings, Twenty-Second Annual Offshore Technology Conference, Houston, Paper No. 6376
Coyle, H. M. and Gibson, G. C. (1970). “Empirical damping constants for sands and clays”. Journal, Soil Mechanics and Foundations Division, ASCE, Vol. 96, No. SM3, pp. 949-965.
Cox, W. R. and Reese, L. C. (1976). “Pullout tests of grouted piles in stiff”, Proceedings, Eighth Offshore Technology Conference, OTC 2473, Houston, Vol. 2, pp. 539-55 1
Datta, M., Gulhati, S. K., and Rao, G. V. (1980). “An appraisal of the existing practice of determining the axial load capacity of deep penetration piles in calcareous sands”, Proceedings, Twelfth Offshore Technology Conference, Houston, Vol. 4, pp. 1 19-1 30
Books on the topic "2D+C (Program)"
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Chang, Jack Keng-Wei, Rob Zhu, Kelvin Sung, and Jebediah Pavleas. Learn 2D Game Development with C#: For IOS, Android, Windows Phone, Playstation Mobile and More. Springer, 2014.
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Hogue, Joe, and Paul Zirkle. iPhone Game Development: Developing 2D and 3D Games in Objective-C. O'Reilly Media, Incorporated, 2009.
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Unity 2020 by Example: A Project-Based Guide to Building 2D, 3D, Augmented Reality, and Virtual Reality Games from Scratch, 3rd Edition. Packt Publishing, Limited, 2020.
Find full textConference papers on the topic "2D+C (Program)"
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Xu, Zhiwei, and Peimin Zhu. "2D random medium inversion algorithm using fuzzy c-means clustering algorithm." In SEG Technical Program Expanded Abstracts 2016. Society of Exploration Geophysicists, 2016. http://dx.doi.org/10.1190/segam2016-13953398.1.
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Antipina, Marina, Ivan Perepletkin, and Vladislav Kuznetsov. "Use of 3-C 2D seismic technology to identify oil-bearing reservoirs." In SEG Technical Program Expanded Abstracts 2018. Society of Exploration Geophysicists, 2018. http://dx.doi.org/10.1190/segam2018-2997832.1.
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Hall, Kevin, Helen Isaac, Joe Wong, Kevin Bertram, Malcolm Bertram, Donald Lawton, Xuewei Bao, and David Eaton. "Initial 3-C–2D surface seismic and walkaway VSP results from the 2015 Brooks SuperCable experiment." In SEG Technical Program Expanded Abstracts 2016. Society of Exploration Geophysicists, 2016. http://dx.doi.org/10.1190/segam2016-13957253.1.
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Mihic, Srdan, and Dragan Ivetić. "A SIMPLE GRAPHICAL FRAMEWORK FOR THE ACQUISITION OF BASIC C PROGRAMMING SKILLS." In eLSE 2012. Editura Universitara, 2012. http://dx.doi.org/10.12753/2066-026x-12-138.
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The introductory (and only) C programming course at the freshmen’s year of Animation Engineering (AE) degree proved to be a challenge, despite 20 years of experience in teaching programming courses. Examples of data abstraction and understanding of control structures and expressions in the C programming language had to be brought closer to students who have shown interest in computer graphics and animation, and thus have chosen to pursue AE degree. Instead of a classical first program - “Hello world”, their first program should show a simple graphical object even it is just a single point. Specifically, students will programmatically control the execution of C program from a console window, whereas graphical window will be used as program’s output. We have chosen to use the Microsoft Visual Studio 2010 integrated development environment (IDE) for this course as it is commonly used in our other C programming courses. Therefore, it had to be adapted to the needs and skills of the AE students. This was accomplished by enabling students to draw graphical objects on a simple 2D graphics canvas but without the need to possess any knowledge of computer graphics. For that purpose, several graphical libraries, including: openBGI, GDI, OpenGL and DirectX, were considered to accommodate the graphical component in the chosen IDE. They were compared according to ease of use, debugging support and documentation availability, from the perspective of absolute programming beginners. We have found that none of them are suitable for first time programmers. Because of this, we have implemented a lightweight wrapper graphical framework that abstracts and hides the underlying complexity of libraries used for drawing on a graphical canvas and window management. The framework offers clean design and ease of use. It provides only a small subset of 2D drawing and window management functions. All framework functions have a reduced number of parameters compared to their underlying counterparts as they set as many parameters as possible to predefined values. In addition, the names of functions are shorter than their counterparts. This way, students have to memorize less and can produce working code faster which should enhance their productivity. This framework, combined with compelling examples and assignments, should help students learn programming with ease.
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Ogbonnaya, Ezenwa A., Hyginus U. Ugwu, Kombo Theophilus-Johnson, Peter B. Forsman, and Charles U. Orji. "Optimizing Gas Turbine Bearing Vibration Using 2D D’Alembert’s Equation." In ASME Turbo Expo 2012: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gt2012-68213.
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The ability to identify faulty equipment under severe conditions allows the manufacturers and operators to take appropriate proactive measures to rectify the faults and provide an assessment for early detection of the engine defects that could lead to catastrophic failure. This work therefore shows that such counter measures can be carried out by optimization, modeling, simulation or using a reliable analysis of gas turbine engine, rotor shaft and bearing vibration data through 2-Dimensional D’Alembert’s equation. Gas turbine plants on industrial duty for electricity generation were thus used to actualize the research. The data for vibration amplitude of rotor bearings from the reference engine which varied between 0.19 and 3.81 mm/s were compared with those obtained from a failed engine of similar characteristics just before failure and used for the simulation and modeling. The given engine speed and active load were also determined as falling between 7264 rpm to 7436 rpm and 10 MW to 20 MW respectively. A well packaged computer program code-named “MELBF” written in C++ programming language was developed. The results show that the machine should not be run beyond 3.81 mm/s vibration amplitude in order to avoid resonance and downtime of the engine.
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Frugier, P., I. Ribet, and T. Advocat. "Effects of Composition Variations on the Alteration Kinetics of the UOX1 “Light Water” Borosilicate Containment Glass." In ASME 2001 8th International Conference on Radioactive Waste Management and Environmental Remediation. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/icem2001-1289.
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Abstract A research and development program was outlined in June 1998 by the CEA’s Rhône Valley Research Center (Valrhô) to model the initial alteration rate r0 between 100°C and 50°C, and the long-term alteration rate r(t) over one year at 50°C, throughout the composition range for the UOX1 “light water” borosilicate containment glass as specified for the R7 and T7 vitrification facilities in the COGEMA reprocessing plant at La Hague. An experimentation plan methodology was set up for this purpose. Seven groups of glass components were designated to assess the influence of composition variations: SiO2, B2O3, Na2O, Al2O3, additive oxides (Fe2O3+NiO+Cr2O3), insoluble fine particle suspensions, and fission product and actinide oxides. The other glass constituents, accounting for 9.5 oxide wt% of the composition, were maintained constant. An empirical synergistic mixing model was postulated, based on first-degree terms and enriched with second-degree terms corresponding to the major interactions liable to exist between some constituents. The NEMROD calculation code was used to select the 22 glass compositions necessary to construct the model (i.e. to determine the values of the 15 coefficients) and the 3 control compositions. The initial rates for all 25 glass compositions were measured in pure water using a Soxhlet test device at 100°C, and in static mode at 50°C. The alteration rates at an advanced degree of reaction progress were determined in static mode at 50°C with a glass-surface-area-to-solution-volume (S/V) ratio of about 60 cm−1. The rates after one year are now available, but the tests are still in progress in order to confirm the stability over time of the steady-state conditions observed. The test results show that the initial alteration rates are clustered around the value obtained for the SON 68 reference glass composition (about 2.4 g·m−2d−1 at 100°C and 0.031 g·m−2d−1 at 50°C), with minor variations between 1.2 and 3.4 g·m−2d−1 at 100°C and between 0.012 and 0.058 g·m−2d−1 at 50°C. These slight rate variations are of considerable significance in view of the wide range of glass compositions investigated. The one-year alteration rates for the test glasses varied by a factor of about 11 around a mean value of 1 × 10−4 g·m−2d−1 at 50°C. The rate variations were modeled as a function of the glass composition variations using the NEMROD program. Other parameter values determined during static testing at the high S/V ratio were also modeled to improve our understanding of the phenomena involved: notably the altered glass thickness after one year. The order of importance of the constituents on the initial rate is not the same as for the final rate, suggesting that the alteration kinetics are controlled by different mechanisms. The initial rate was influenced primarily by the following constituents (by order of importance): the fission product oxides and SiO2 (increasing durability at increasing concentrations) and B2O3 (diminishing durability at increasing concentration). Conversely, the one-year alteration rates were found statistically to depend much more on the variability of the Na2O, Al2O3 and FP oxide concentrations than on the SiO2 concentration. Several hypotheses are proposed to account for these effects.
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Lima, Phyllipe, Eduardo Guerra, and Paulo Meirelles. "Towards Visualizing Code Annotations Distribution." In Computer on the Beach. Itajaí: Universidade do Vale do Itajaí, 2020. http://dx.doi.org/10.14210/cotb.v11n1.p277-284.
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Java developers make extensive use of code annotations sincetheir introduction in version 5 of the language. They areinserted directly on the source code for custom metadata configuration,similar to C# attributes. The software engineeringcommunity has few works investigating their usage and impacton source code. Being able to visualize characteristics ofcode annotations might aid developers in detecting potentialmisuse, outliers as well as increase the comprehensibility andreadability of the source code. In this paper, we present anapproach to use software metrics to generate a 2D polymetricview targeting the visualization of code annotations in Javaclasses. We developed a prototype tool using the Unity GameEngine. It displays classes and packages as rectangles andannotations as circles. We demonstrated the tool with a smallsample Java program.
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Wilkinson, Michael P., and Marina B. Ruggles-Wrenn. "Mechanical Properties and Fatigue Behavior of 2D Woven PMC and Unitized Composite Airframe Structures at Elevated Temperature." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-65763.
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Airframe structures and components on many existing and future Air Force aerospace systems require operation in elevated temperature. Examples include hypersonic vehicle airframes, engine related components (such as engine ducts, engine vanes, and exhaust flaps), and hot trailing edges of B-2 and C-17 wings. Material systems that show improved fatigue performance, excellent thermal resistance, and damage tolerance are prime candidate materials for potential air vehicle structural components. Polymer matrix composites (PMCs) and ceramic matrix composites (CMCs) are two types of composites used in aircraft structures subjected to high temperatures. The polymer matrix in most PMCs cannot withstand the temperatures required for many aerospace structural applications. Therefore, either improvements in temperature capability of polymer matrix materials or developing novel thermal protection systems are desired for elevated temperature applications. Any new material system intended for aerospace applications must be studied and tested to verify that the mechanical properties are sufficient for use in the operating environments. This study investigated the mechanical properties and tension-tension fatigue behavior of two newly developed material systems for use in structures subjected to elevated temperatures, namely a 2D weave PMC and a 2D weave unitized composite (or PMC/CMC, consisting of a PMC co-cured with a CMC layer to act as a thermal barrier). These two material systems are two of three new composites developed under contract through the Air Force Research Laboratory (AFRL) and investigated during a master’s thesis research program at the Air Force Institute of Technology (AFIT) [1]. The 2D PMC investigated in this effort consisted of an NRPE (a high-temperature polyimide) matrix reinforced with carbon fibers. The fiber architecture of the PMC was an 8 harness satin weave fiber fabric. The PMC portion of the unitized composite had the same constituent properties and weave as the aforementioned 2D PMC. The CMC layer consisted of a zirconia-based matrix reinforced with an 8 harness satin weave quartz fiber fabric. For both material systems (PMC and PMC/CMC), material properties were investigated for both on-axis [0°/90°] and off-axis [±45°] fiber orientations. Tensile properties were evaluated at (1) room temperature and (2) with one side of the specimen at 329 °C and the other side exposed to ambient air. Tension-tension fatigue tests were conducted at elevated temperature at a frequency of 1.0 Hz with a ratio of minimum stress to maximum stress of R = 0.05. Fatigue run-out for this effort was defined as 2×105 cycles. Elevated temperature had little effect on the tensile properties of both material systems with the 0°/90° fiber orientation; however, specimens with the ±45° fiber orientation exhibited a significant increase in failure strain at elevated temperature. The ultimate tensile strength (UTS) of the 2D PMC with the ±45° fiber orientation decreased slightly at elevated temperature, but the UTS of the unitized composite with ±45° fiber orientation showed no significant change. The unitized composite did not exhibit an increase in tensile strength and stiffness compared to the 2D PMC. However, the 2D PMC with ±45° fiber orientation produced significantly greater failure strain. The 2D PMC showed slightly better fatigue resistance than the unitized composite with the 0°/90° fiber orientation. For the ±45° fiber orientation, the fatigue limit for the 2D PMC was approximately two times greater than that for the unitized composite. Microstructural investigation of tested specimens revealed delamination in the 2D PMC and very severe delamination in the unitized composite.
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Timms, Chris, Luciano Mantovano, Hugo A. Ernst, Rita Toscano, Duane DeGeer, Doug Swanek, Marcos de Souza, and Luis C. Chad. "The Influence of the UOE Forming Process on Material Properties and Collapse of Deepwater Linepipe." In ASME 2009 28th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/omae2009-80179.
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It has been demonstrated in previous work that, for deepwater applications, the cold forming process involved in UOE pipe manufacturing significantly reduces pipe collapse strength. To improve the understanding of these effects, Tenaris has embarked on a program to model the stages of the UOE manufacturing process using finite element methods. Previous phases of this work formulated the basis for model development and described the 2D approach taken to model the various stages of manufacture. More recent developments included some modeling enhancements, sensitivity analyses, and comparison of predictions to the results of full-scale collapse testing performed at C-FER. This work has shown correlations between manufacturing parameters and collapse pressure predictions. The results of the latest phase of the research program are presented in this paper. This work consists of full-scale collapse testing and extensive coupon testing on samples collected from various stages of the UOE pipe manufacturing process including plate, UO, UOE, and thermally-aged UOE. Four UOE pipe samples manufactured with varying forming parameters were provided by Tenaris for this test program along with associated plate and UO samples. Full-scale collapse and buckle propagation tests were conducted on a sample from each of the four UOE pipes including one that was thermally aged. Additional coupon-scale work included measurement of the through-thickness variation of material properties and a thermal ageing study aimed at better understanding UOE pipe strength recovery. The results of these tests will provide the basis for further refinement of the finite element model as the program proceeds into the next phase.
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Atayılmaz, S¸evket O¨zgu¨r, Hakan Demir, O¨zden Ag˘ra, and I˙smail Teke. "An Experimental Apparatus to Investigate Natural Convection Heat Transfer From a Vertical Array of Isothermal Horizontal Cylinders." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-38634.
Full textAbstract:
Steady natural convection heat transfer from vertical array of equally-spaced isothermal horizontal cylinders has been investigated experimentally and numerically. Experimental study was carried out at different ambient temperatures in a conditioned room which can be maintained at a stable required value and inside a sufficiently designed test cabin. The ambient and cylinders’ surface temperatures varied 20°C to 30°C and 30°C to 60°C respectively. The experimental apparatus was designed to adjust different operating parameters such as number of cylinders, cylinders’ surface temperatures, distance between the cylinders and environmental temperature. Each cylinder surface temperature can be accurately adjusted to the desired temperature by means of specially designed measurement and control system. Copper test cylinders have length of 1 m and outer diameter of 4.8 mm. The uncertainty analysis method proposed by Kline and McClintock was used and explained elaborately. Detailed information and algorithm of numerical method are given to ease the understanding of the numerical part of the study. The problem was solved numerically by means of a CFD program in 2D. Average Nusselt numbers are given based on the experimental data for single and each two horizontal cylinders. Heat transfer rates obtained from experimental and numerical studies for upper and lower cylinders were compared with each other. The deviation of experimental and numerical heat transfer rates are in a good agreement and stay in the range ± 20%. It is seen that heat transfer from the lower cylinder is close to the single cylinder case. However, higher temperature of the passing air reduces the heat transfer from the upper cylinder for S/D = 2.