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Linearization of two-state thruster models

Journal of Physics: Conference Series 2020年第1期1490卷

作者： Dieky Adzkiya Hendro Nurhadi Teguh Herlambang Department of Mathematics Institut Teknologi Sepuluh Nopember Indonesia Center of Excellence for Mechatronics and Industrial Automation Research Center Institut Teknologi Sepuluh Nopember Indonesia Department of Industrial Mechanical Engineering Institut Teknologi Sepuluh Nopember Indonesia Study Program of Information Systems Universitas Nahdlatul Ulama Surabaya Indonesia

A thruster is a device used for station keeping, attitude control, in the reaction control system, or long-duration, low-thrust acceleration. Thruster is one of the main components in autonomous surface vehicle. In th...

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WARSHIPS AND COST CONSTRAINTS

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NAVAL ENGINEERS JOURNAL 1986年第2期98卷 41-52页

作者： HOPE, JP STORTZ, VE Jan Paul Hope a native of Northern Virginia received his bachelor of science degree in mechanical engineering from the University of Virginia in 1969. Upon graduation he began his career in the Department of the Navy with the Naval Ship Systems Command in the acquisition of patrol craft mine sweepers and submarine rescue ships. In January 1971 he transferred to the ship arrangements branch of the Naval Ship Engineering Center. He was selected for the long-term training program at George Washington University in 1974 and completed the program in February 1976 with the degree of master of engineering administration. While at the Naval Ship Engineering Center Mr. Hope was general arrangement task leader on the AO-177 CG-47 CSGN CSGN (VSTOL) CGN-9 (Aegis) and CGN-42 and he also assisted in the landmark Naval Sea Systems Command civilian professional community study. In 1978 he was selected as acting head of the damage control section and subsequently was selected as acting head of the surface ship hydrodynamic section. In February 1980 he was promoted to head of the surface combatant arrangements design section. Mr. Hope was selected for the first class of the NA VSEA commander's development program. While on the program he served in the DDGX combat systems engineering division and the DDGX project office of NA VSEA was the assistant director for ship design in the office of the Assistant Secretary of the Navy for shipbuilding and logistics and was the director of weight engineering and the director of systems engineering for the DDG-51 project in NA VSEA. Upon completion of the program Mr. Hope was assigned as the deputy director of the boiler engineering division to create a new division as a major fleet support initiative by NA VSEA. In June 1985 he joined the staff of the Assistant Secretary of the Navy for shipbuilding and logistics. Mr. Hope was presented the Department of the Navy meritorious civilian service medal in June 1983 for his service with the Office of the Assistant Secretary of the

This paper discusses the need and processes for designing warships to meet cost constraints and for managing warship acquisition programs during the design phase to assure effective adherence to production cost constraints by the design team. The resource control methodology used during the contract design of the Arleigh Burke class destroyer, DDG-51, is examined as a potential model for controlling the cost while maintaining the combat effectiveness of warships. The paper begins with a summary of the basic issue — the relationship among unit cost, unit capability, force level numbers, and force capability — showing recent trends in destroyer costs and force levels. This introduction also includes a discussion of the cost constraint for the DDG-51 in relation to historical trends and ship construction funding allocation. The resource control methodology used to reduce and control costs of the DDG-51 is discussed with a summary of the approach, key concepts and tools, chronology of key events, examples, and results achieved. A number of observations on this methodology are then made which are followed by comments on life cycle costs. The paper concludes with remarks on the future application of the resource control methodology and areas for further work to improve future resource control efforts.

关键词： WARSHIPS

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Technology integration in mechanical engineering vocational education: engineering mathematics and engineering physics

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AIP Conference Proceedings 2023年第1期2720卷

作者： Rochmad Novian Inderanata Thomas Sukardi Putu Sudira Tuti Purwaningsih Slamet Priyanto Doctoral Program Student in Technology and Vocational Education Yogyakarta State University Yogyakarta Indonesia Mechanical Engineering Education Department Yogyakarta State University Yogyakarta Indonesia Technology and Vocational Education Graduate Schools Yogyakarta State University Yogyakarta Indonesia Statistics Department Universitas Islam Indonesia Yogyakarta Indonesia Mechanical Engineering Vocational Education Department Universitas Sarjanawiyata Tamansiswa Yogyakarta Indonesia

Technology integration has been applied in the industrial world for the production process, distribution, employment to worker training. The training in Vocational Education is expected to facilitate every learning with various technological transformations that develop. engineering Mathematics and engineering Physics are lessons that must be given to vocational students as a vocational basis. This study aims to explore the impact of using technology in vocational learning. This study uses qualitative research methods, with an emic approach. The theories used are: (1) Critical Theory from Max Horkheimer and Theodor W. Adorno regarding assumptions; (2) Technology Acceptance Model (TAM) theory regarding perceived usefulness and perceived ease of use; and (3) the concept of Ki Hadjar Dewantara’s teachings about “ngerti”, “ngroso” and “nglakoni". The results of this study are: (1) the integration of technology provides benefits to student learning activities seen from the critical theory that learning theory is not boring so that students become more active to take part in learning engineering mathematics and engineering physics; (2) the integration of technology in learning provides positive emotions for students in terms of the perceived benefits and perceived ease of use both from the software and hardware devices they have to solve problems in engineering mathematics and engineering physics; (3) technology integration benefits students’ curiosity about "ngerti", "ngroso" and "nglakoni" according to the concept of Ki Hadjar Dewantara’s teachings seen from seeing the lecturer in explaining the material, demonstrating software and hardware devices, viewing, remember and mark, and imitate implementation in everyday life.

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mechanical properties of bacterial nanocellulose membrane from pineapple peel waste after homogenization process

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AIP Conference Proceedings 2019年第1期2120卷

作者： Taufiq Mahsuli Heru Suryanto Aisyah Larasati Muhammad Muhajir 1Master Student of Mechanical Engineering Program Graduate School Universitas Negeri Malang Jl. Semarang 5 Malang East Java Indonesia 2Centre of Advanced Materials for Renewable Energy Universitas Negeri Malang Jl. Semarang 5 Malang East Java Indonesia65140 3Mechanical Engineering Department Engineering Faculty Universitas Negeri Malang Jl. Semarang 5 Malang East Java Indonesia 4Department of Industrial Engineering Faculty of Engineering Universitas Negeri Malang Jl. Semarang 5 Malang East Java Indonesia

Bacterial nanocellulose (BNC) has unique physical properties such as having high crystallinity, mechanical strength, purity, porosity, high water absorption capacity and biodegradable. This research aims to investigate the effect of high-pressure homogenizer (HPH) treatment cycle on the tensile strength and morphology of BNC membrane. This experiment begins from pineapple peel waste juice added with Acetobacter xylinum incubated for 14 days. The yielded pellicle then washed by distilled water then immersed in 1% NaOH for 24 h and pellicle well disintegrated using a high-speed blender, followed by homogenizing using HPH with repetition of 5 cycles at 150 bar. The solution was cast into a rectangular glass container and dried into an oven at 60 °C for 8 h. Results show that the tensile strength of BNC was 77.76 MPa and 75.97 MPa for membrane without HPH process and HPH process, respectively. The elastic modulus of BNC was16 GPa and 27.25 GPa for membrane without HPH process and HPH process, respectively. Morphological analysis using Scanning electron microscopy (SEM) showed the pores of BNC membrane prepared using HPH smaller than non-HPH. This means that the BNC membrane prepared by HPH was dense compared than Non-HPH membrane. Dense membrane caused a higher strength of the membrane.

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Internal nanostructure diagnosis with hyperbolic phonon polaritons in hexagonal boron nitride

arXiv

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arXiv 2018年

作者： Dai, Siyuan Tymchenko, Mykhailo Xu, Zai-Quan Tran, Toan T. Yang, Yafang Ma, Qiong Watanabe, Kenji Taniguchi, Takashi Jarillo-Herrero, Pablo Aharonovich, Igor Basov, Dimitri N. Tao, Tiger H. Alù, Andrea Department of Electrical & Computer Engineering University of Texas AustinTX78712 United States Institute of Biomedical Materials and Devices Faculty of Science University of Technology Sydney UltimoNSW2007 Australia Department of Physics Massachusetts Institute of Technology CambridgeMA02215 United States National Institute for Materials Science Namiki 1-1 Tsukuba Ibaraki305-0044 Japan Department of Physics Columbia University New YorkNY10027 United States Department of Mechanical Engineering University of Texas AustinTX78712 United States Photonics Initiative Advanced Science Research Center City University of New York New York10031 United States Physics Program Graduate Center City University of New York New York10016 United States Department of Electrical Engineering City College of the City University of New York New York10031 United States

Imaging materials and inner structures with resolution below the diffraction limit has become of fundamental importance in recent years for a wide variety of applications. In this work, we report sub-diffractive internal structure diagnosis of hexagonal boron nitride by exciting and imaging hyperbolic phonon polaritons. Based on their unique propagation properties, we are able to accurately locate defects in the crystal interior with nanometer resolution. The precise location, size and geometry of the concealed defects is reconstructed by analyzing the polariton wavelength, reflection coefficient and their dispersion. We have also studied the evolution of polariton reflection, transmission and scattering as a function of defect size and photon frequency. The nondestructive high-precision polaritonic structure diagnosis technique introduced here can be also applied to other hyperbolic or waveguide systems, and may be deployed in the next-generation bio-medical imaging, sensing and fine structure analysis. Copyright © 2018, The Authors. All rights reserved.

关键词： Van der Waals forces

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UNDERWATER INSPECTION FOR WELDING AND OVERHAUL

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NAVAL ENGINEERS JOURNAL 1993年第5期105卷 37-42页

作者： MITTLEMAN, J SWAN, L John Mittleman:is a mechanical engineer at the Naval Surface Warfare Center Dahlgren Division Coastal Systems Station in Panama City Florida. His Primary Responsibilities are in the development of underwater nondestructive testing equipment for use by fleet divers and inspectors. He also performs research in the characterization of metal microstructure through ultrasonic scattering measurements. Mr. Mittleman received his BS from Cornell University in 1969 and science master's in ocean engineering from the Massachusetts Institute of Technology in 1970. His research currently supports doctoral studies with Iowa State University. Mr. Mittleman received the American Society of Naval Engineer's Solberg Award in 1981 for his contributions to underwater ship hull inspection. Mr. Mittleman is a member of ASNE ASNT ASTM IoD Sigma Xi Tau Beta Pi and Phi Kappa Phi. Lisa Swan:is a mechanical engineer at the Naval Surface Warfare Center in Panama City Florida. She is involved in nondestructive testing engineering primarily in the underwater arena. Ms. Swan holds a bachelor of science in materials engineering from North Carolina State University. She is a graduate of the Federal Women's Executive Leadership Program. Ms. Swan is a member of ASNT.

Significant progress has been made in making underwater ultrasonic thickness gauging and magnetic particle inspections available to the fleet. Under sponsorship from the Naval Sea systems Command, Director of Ocean engineering, Underwater Ship Husbandry Division (NavSea 00C5), the Coastal systems Station has developed complete hardware packages supporting these two nondestructive test methods, and has introduced them to military inspectors at a shore intermediate maintenance activity, a destroyer tender, and a naval shipyard. Performance trials conducted prior to taking the systems to the field have been accepted by NavSea, Ships' Concepts Group, Materials Subgroup, Metals Division (NavSea 5142) as evidence that these inspections can reliably be performed underwater. Avenues for certifying specially trained divers and inspectors are being developed;for the first time the Navy will have all of the elements in place for underwater inspections satisfying the requirements of Mil-Std-271 (Requirements for Nondestructive Testing Methods) and the Naval Ships' Technical Manual Chapter 074. Underwater ultrasonic thickness gauging has also been slated for use in the fleet, as data from laboratory and field trials have consistently shown that reliable results can be obtained by a team comprising a certified topside inspector and a diver. In tests performed at the Ship Repair Facility (SRF), Yokosuka, underwater readings were compared to those taken in dry dock by SRF inspectors, and independently by contract inspectors. On the basis of approximately 800 locations, differences between the data sets were found to be randomly distributed, with a standard deviation on the order of 0.02''. This level of accuracy is largely sufficient to distinguish plate which will need replacement during overhaul, or plate which is thick enough to weld on.

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A LOOK AT FUSION POWER

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NAVAL ENGINEERS JOURNAL 1981年第5期93卷 49-59页

作者： DANIELSON, WF was born in 1939 in New York City. He received his B.S. Marine Engineering from the State University of New York Maritime College in 1961 along with a USNR Commission and the USCG license of third engineer. In later years he completed graduate work in both mechanical and nuclear engineering at Carnegie-Mellon University and the University of Idaho. Work experience started with two years sea duty on MSTS vessels then ashore with the MW Kellogg Company as systems engineer designing petrochemical plants. He changed employment to the New York Telephone Co. as mechanical engineer involved in building design and HVAC. In 1967 he was hired by Bettis Atomic Power Laboratory as Irradiation Facilities Engineer. He progressed from engineer to senior engineer at Bettis and significant assignments included cognizant engineer on test reactor loops and plant designer on the Advanced Submarine Project. In 1973 Bettis transferred him to the Naval Reactor's Facility in Idaho where he became Supervisor then Manager of Radiological Design and Engineering. In this capacity he was responsible as an approval agent for all maintenance and revamp work packages on four operating nuclear reactors. Since 1977 he has been employed at Argonne National Laboratory- West as project engineer or project manager on various assignments in support of the Experimental Breeder Reactor Program and Site Engineering. He has been a member of ASNE since 1972.

Fusion power is produced from a controlled thermonuclear reaction inside the fusion device. The early sections of this article discuss fusion fuel, its transformation into plasma, and the required character of this working substance for power production. Next, the thermonuclear reaction is investigated and it is shown that it will become self-sustaining with a net power output. Later sections review a typical fusion device and answer why a reaction at 100 million degrees can be adequately contained using magnetic fields. Lastly, a preferred fusion device is examined for operational restraints and a simplified operating scenario of such a device is outlined.

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MACHINERY ARRANGEMENT DESIGN - A PERSPECTIVE

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NAVAL ENGINEERS JOURNAL 1981年第3期93卷 133-141页

作者： RESNER, ME KLOMPARENS, SH LYNCH, JP Mr. Michael E. Resner:received an Engineering Degree from Texas A&M University in 1966 and has done graduate work in management at American University. He is Director Machinery Arrangements/Control Systems and Industrial Facilities Division (SEA 525) at the Naval Sea Systems Command. His previous positions have included Program Manager Solar Total Energy Program at the Department of Energy and Branch Chief Machinery Control Systems Branch at the Naval Ship Engineering Center. Mr. Stephen H. Klomparens:is a Naval Architect at Designers & Planners Inc. and is engaged in development of computer aids for ship design. He received his B.S.E. degree in Naval Architecture and Marine Engineering from the University of Michigan in 1973 and his M.S. degree in Computer Science from the Johns Hopkins University. Mr. Kolmparens began his professional career at Hydronautics Inc. in 1974 where he was involved in the use of marine laboratory facilities for test and development of conventional and advanced marine craft. Since 1977 he has been involved with naval and commercial ship design and with development of computer-aided ship design tools. Mr. John P. Lynch:is a Principal Marine Engineer with Hydronautics Inc. He was previously employed in the auxiliary machinery and computer-aided design divisions of the David W. Taylor Naval Ship R&D Center the machinery design division of the New York Naval Shipyard and the machinery arrangement code of the Bureau of Ships. His active naval service was as a ship superintendent in the production department of the Long Beach Naval Shipyard. Mr. Lynch received his B. S. degree in Marine Engineering from the New York State Maritime College and his M.S. degree in Mechanical Engineering from Columbia University. He is a licensed Professional Engineer in the State of New York and a member of ASNE.

The machinery arrangement design process has remained relatively unchanged over the years. Recently, external demands have been placed on both the product and the producers that call for changes to this process. This paper cites these external demands and traces the evolution of the process changes from the rule-of-thumb machinery box sizing routines up to the current automated procedures. The machinery arrangement design practice is presented, and existing analytic and graphics aids are discussed. The user requirements for improved design aids are presented, with implementation guidelines and hardware/software alternatives.

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Effects of sodium alginate-poly(acrylic acid) cross-linked hydrogel beads on soil conditioner in the absence and presence of phosphate and carbonate ions

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Case Studies in Chemical and Environmental engineering 2024年 9卷

作者： Hidayat, Endar Sarbani, Nur Maisarah Mohamad Lahiri, Sudip Kumar Samitsu, Sadaki Yonemura, Seiichiro Mitoma, Yoshiharu Harada, Hiroyuki Graduate School of Comprehensive Scientific Research Program in Biological System Sciences Prefectural University of Hiroshima Shobara 727-0023 Japan Department of Life System Science Faculty of Bioresources Science Prefectural University of Hiroshima Shobara 727-0023 Japan Data-driven Polymer Design Group Research Center for Macromolecules and Biomaterials National Institute for Materials Science 1−2−1 Sengen Tsukuba 305-0047 Japan Department of Mechanical & Industrial Engineering University of Toronto Toronto M5S 3G8 ON Canada Faculty of Allied Health Sciences Chettinad Hospital and Research Institute Chettinad Academy of Research and Education Tamil Nadu Kelambakkam 603103 India

Hydrogel beads, composed of polymers, possess the ability to absorb substantial quantities of water simultaneously and gradually release it in dry conditions. In this work, hydrogel beads were synthesized using sodium alginate (S-Alg) and poly (acrylic acid) (P-Acc), either in the absence or presence of phosphate (PO₄ ³⁻) (S-Alg/P-Acc@PO₄ ³⁻) and carbonate (CO₃ ²⁻) anionic ions (S-Alg/P-Acc@CO₃ ²⁻). Subsequently, these beads were crosslinked with Ca²⁺ ions. The scanning electron microscopy (SEM) images demonstrated that the presence of anionic ions has an impact on the structure of the hydrogel beads and enhances porosity expansion while concurrently reducing the concentration of carboxyl (COOH) groups. The hydrogel beads exhibited a great swelling behavior, with S-Alg/P-Acc@CO₃ ²⁻ capable of absorbing up to 73.5 % of water in acidic conditions, but decreased under neutral and basic conditions. Soil water loss (SWL) experiments confirmed the ability of hydrogel beads to retain water in the soil. Additionally, observations of soil characteristics after a 14-day treatment revealed no significant difference in pH and C/N ratio (P-value <0.05). However, soil's available Fe and N–NO₃ ^- significantly reduced (P-value <0.05) while substantially promoting soil N–NH₄ ⁺, available phosphorus (P), cation exchange capacity (CEC), soil organic carbon (SOC), and exchangeable cation (Ca²⁺, K⁺ and Mg²⁺). The presence of hydroxyl (-OH) and –COOH groups was found to be crucial for enhancing soil properties. © 2024 The Authors

关键词： Anionic ions Hydrogel beads Poly (acrylic acid) Sodium alginate Soil characteristics Soil water retention Swelling

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Considering discrepancy when calibrating a mechanistic electrophysiology model

arXiv

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arXiv 2020年

作者： Lei, Chon Lok Ghosh, Sanmitra Whittaker, Dominic G. Aboelkassem, Yasser Beattie, Kylie A. Cantwell, Chris D. Delhaas, Tammo Houston, Charles Novaes, Gustavo Montes Panfilov, Alexander V. Pathmanathan, Pras Riabiz, Marina Weber dos Santos, Rodrigo Worden, Keith Mirams, Gary R. Wilkinson, Richard D. Computational Biology & Health Informatics Dept. of Computer Science University of Oxford United Kingdom MRC Biostatistics Unit University of Cambridge United Kingdom Centre for Mathematical Medicine & Biology School of Mathematical Sciences University of Nottingham United Kingdom Department of Bioengineering University of California San Diego United States Systems Modeling and Translational Biology GlaxoSmithKline R&D Stevenage United Kingdom ElectroCardioMaths Programme Centre for Cardiac Engineering Imperial College London United Kingdom CARIM School for Cardiovascular Diseases Maastricht University Netherlands Graduate Program in Computational Modeling Universidade Federal de Juiz de Fora Brazil Department of Physics and Astronomy Ghent University Belgium Laboratory of Computational Biology and Medicine Ural Federal University Ekaterinburg Russia U.S. Food and Drug Administration Center for Devices and Radiological Health Office of Science and Engineering Laboratories United States Department of Biomedical Engineering King’s College London Alan Turing Institute United Kingdom Dynamics Research Group Department of Mechanical Engineering University of Sheffield United Kingdom School of Mathematics and Statistics University of Sheffield United Kingdom

Uncertainty quantification (UQ) is a vital step in using mathematical models and simulations to take decisions. The field of cardiac simulation has begun to explore and adopt UQ methods to characterise uncertainty in model inputs and how that propagates through to outputs or predictions. In this perspective piece we draw attention to an important and under-addressed source of uncertainty in our predictions — that of uncertainty in the model structure or the equations themselves. The difference between imperfect models and reality is termed model discrepancy, and we are often uncertain as to the size and consequences of this discrepancy. Here we provide two examples of the consequences of discrepancy when calibrating models at the ion channel and action potential scales. Furthermore, we attempt to account for this discrepancy when calibrating and validating an ion channel model using different methods, based on modelling the discrepancy using Gaussian processes (GPs) and autoregressive-moving-average (ARMA) models, then highlight the advantages and shortcomings of each approach. Finally, suggestions and lines of enquiry for future work are provided. Copyright © 2020, The Authors. All rights reserved.

关键词： Uncertainty analysis

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