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Advanced Mechanical Vibrations: Physics, Mathematics and Applications
No full textAdvanced Mechanical Vibrations: Physics, Mathematics and Applications provides a concise and solid exposition of the fundamental concepts and ideas that pervade many specialised disciplines where linear engineering vibrations are involved. Covering the main key aspects of the subject – from the formulation of the equations of motion by means of analytical techniques to the response of discrete and continuous systems subjected to deterministic and random excitation – the text is ideal for intermediate to advanced students of engineering, physics and mathematics. In addition, professionals working in – or simply interested in – the field of mechanical and structural vibrations will find the content helpful, with an approach to the subject matter that places emphasis on the strict, inextricable and sometimes subtle interrelations between physics and mathematics, on the one hand, and theory and applications, on the other hand. It includes a number of worked examples in each chapter, two detailed mathematical appendixes and an extensive list of references
Rotating Machinery, Vibro-Acoustics & Laser Vibrometry, Volume 7
No full textRotating Machinery, Vibro-Acoustics & Laser Vibrometry, Volume 7: Proceedings of the 36th IMAC, A Conference and Exposition on Structural Dynamics, 2018, the seveth volume of nine from the Conference brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Rotating Machinery, Hybrid Testing, Vibro-Acoustics & Laser Vibrometry, including papers on:
Rotating Machinery
Vibro-Acoustics
Experimental Techniques
Scanning Laser Doppler Vibrometry Method
Fundamentals of Human Resource Management, 8/E.
No full textA highly reliable, easy-to-use homework and learning management solution that embeds learning science and award-winning adaptive tools to improve student results.
- Provides a complete introduction to human resource management for the general business manager who wants to learn more about how HRM is used in the everyday work environment.
- The author team’s areas of expertise span the entire spectrum of topics covered in a Human Resource Management course, which allows for a text that is more current and cutting edge
Geotechnical Characterisation and Geoenvironmental Engineering: IGC 2016 Volume 1
No full textIntroduction
The book comprises selected proceedings of the 2016 annual conference of the Indian Geotechnical Society. The technical papers presented on the theme “Geotechnical Characterisation and Geoenvironmental Engineering” highlight the modified geotechnical properties of soil admixed industrial waste and also the characteristics of soil with different pore fluid under varying test conditions. The major topics covered are (i) characterisation of soils, rocks and synthesised materials and (ii) geoenvironmental engineering and behaviour of unsaturated soil. This book will prove a valuable reference for researchers and practicing engineers alike.
Keywords
Clay soil stabilizationGeotechnical CharacterisationGeoenvironmental EngineeringSeismic Isolation applicationsBlended Geopolymer compositesSoil CompactionSlope StabilityGeomaterialsBiomineralisatio
Business Intelligence, Analytics, and Data Science: A Managerial Perspective, 4/E.
No full textA managerial approach to understanding business intelligence systems.
To help future managers use and understand analytics, Business Intelligence provides students with a solid foundation of BI that is reinforced with hands-on practice
Development of control concepts for improved driving dynamics of harvesting machines with large headers
No full textThis book examines the driving dynamics of harvesting machines with large harvesting heads. It looks at how to efficiently use these machines. The author explores a common problem that hinders machine performance when harvesting with very large headers. He deals with concepts for reducing the undesired effects of vehicle dynamics when using these machines.
With the steadily increasing capacity of harvesting machines, the working widths of the harvesting heads get wider and the headers get heavier. It has become essential with these giant headers to use header height sensors and header control systems to avoid the headers from being run into the ground when encountering elevation changes in the terrain. A fundamental limitation of the viable speed of header height adjustments arises from the combination of the wider and heavier headers with soft agricultural tires.
The current solution to find an appropriate speed of header height adjustments is to perform a header calibration whenever a new header is attached to the machine and to endow the machine operator with the capability to tweak the speed of adjustments manually. The result of an inappropriate speed of height adjustments is a reduction in overall productivity and an under-utilization of the harvesting machine. The author looks at ways to prevent this. He offers detailed modeling of the vertical dynamics including dynamic wheel loads. In addition, the book contains results from simulations and machine tests.
The Author
Dr.-Ing. Benedikt Jung studied Mechanical Engineering and Automotive Systems Engineering with a focus on Automation and Turbomachinery. Between 2014 and 2018 he was an external PhD student at the Institute of Agricultural Systems at the Technical University of Dresden. Since 2011, he works in the Research and Development department of a global manufacturer of Agricultural machinery
PENGARUH POLA TIUP UDARA TERHADAP KINERJA KOMPOR GASIFIKASI TIPE DOWNDRAFT DAN UPDRAFT
No full textPemanfaatan biomassa sebagai bahan bakar merupakan solusi yang tepat untuk penanganan sumber energi fosil yang semakin menipis. Pada penelitian ini menggunakan kompor gasifikasi biomassa tipe downdraft dan updraft dengan bahan bakar (wood pellet) dan menggunakan metode Standar Nasional Indonesia (SNI 7926:2013) Tungku Biomassa. Penelitian ini bertujuan untuk mengetahui kinerja kompor gasifikasi dari dua variasi pola tiup udara yaitu cyclone dan direct. Pada penelitian ini menggunakan gasifier dengan ketinggian 20 cm serta memiliki lubang sebanyak 40 buah. Setiap pengujian dilakukan dengan empat variasi kecepatan (m/s), yaitu 4,5; 5; 5,4 dan 5,7 dan tiga variasi jumlah bahan bakar (gr), yaitu 400, 600 dan 800. Menurut Metode SNI, nilai efisiensi termal minimum adalah 20% dan nilai FCR maksimum adalah 1kg/jam. Hasil dari pengujian kompor gasifikasi tipe updraft dengan pola tiup udara cyclone meiliki kinerja yang lebih baik. Kompor gasifikasi tipe tersebut memiliki nilai efisiensi termal tertinggi yaitu 13,52%, FCR sebesar 1,64 kg/jam, persentase char yaitu 1,88%, waktu untuk mendidihkan air tercepat yaitu 562 detik (9,3 menit), laju kalor tertinggi yaitu 964,402 kkal/jam, suhu api maksimum yaitu 824,56?, serta persentse warna api biru sebesar 30,38% dan warna api merah sebesar 40,32% pada kecepatan udara 5,4 m/s dan bahan bakar 800 gr.
Kata kunci : kompor gasifikasi; pola tiup udara; biomassa; updraft cyclone; wood pellet
PERANCANGAN ALAT PENGIRIS TEMPE PADA UMKM CC DENGAN METODE PERANCANGAN PRODUK RASIONAL
No full textProses produksi merupakan elemen penting dalam suatu pengolahan yang harus diperhatikan karena akan berpengaruh pada hasil kualitas yang didapatkan seperti proses pengirisan yang terdapat pada UMKM CC. Pada proses pengirisan ini UMKM CC hanya menggunakan alat sederhana yaitu pisau dapur dimana proses pengirisan banyak menghabiskan waktu dan irisan tidak konsisten. Untuk membuat pengirisan menjadi cepat dan mendapatkan irisan konsiten diperlukan alat bantu dan dibuatlah konsep alat bantu pengirisan tempe dengan metode perancangan produk rasional dengan beberapa tahap yaitu clarifying objectives, establish function, setting requirement, determining characteristics, generating alternatives, dan evaluating alternatives dengan kemudian didapatkan Concept Scoring dengan total nilai 3.66 yang dimana konsep desain tersebut bisa memenuhi keinginan konsumen yang dapat membuat irisan konsisten 3mm, mengurangi durasi waktu pengirisan kurang dari 1 menit dan menjadi konsep yang terpilih.
Kata Kunci : UMKM CC, Waktu Irisan, Irisan Konsisten, Perancangan Produk Rasional, dan Konsep Desain
Reliability of Selective Laser Melted AlSi12 Alloy for Quasistatic and Fatigue Applications: With a Foreword by Prof. Dr. Frank Walther
No full textSelective laser melting (SLM) is an established additive manufacturing process
which can manufacture intricate parts with almost full density. The competitive
advantages of the process are potential of customization as well as design
optimization for light-weighting. The current state of the art recommends that
utilization of the technology can now be extended from rapid prototyping to serial
production for functional applications. Employment of the technology for
functional applications requires not only the resulting density higher than 99%;
reliability of the structures under mechanical loading is the most important
parameter. To ensure reliability, influence of the processing and post-processing
conditions needs to be understood. As many of the applications of SLM process
are in automotive and aerospace industries, fatigue reliability of the parts plays the
foremost role.
This study focuses on the investigation of process chain on the material properties
and the corresponding mechanical behavior. Metallographic techniques like light
and electron microscopy, non-destructive micro-computed tomography are
employed to investigate the material structural properties which are then used to
comprehend the mechanical behavior in quasistatic, high cycle fatigue (HCF),
very high cycle fatigue (VHCF) as well as in crack propagation. Role of processinduced microstructure and defects in fatigue reliability has been discussed, and a
fatigue prediction methodology has been developed based on cyclic deformation
behavior, statistical analysis of defects and finite element analysis. Additionally,
realizability of manufacturing hybrid structures and their influence on part
reliability is also investigated.
The results indicate that the quasistatic strength of SLM-processed AlSi12 alloy is
higher than that of cast alloy due to process-specific structural features, and the
individual processing conditions need to be customized according to the required
properties. For fatigue testing, combined load increase tests with continuously
varying amplitude and constant amplitude tests help expediting the optimization
procedure. SLM can be used for generation of parts with localized properties.
Combination of conventional and additive manufacturing can be successfully
carried out with appropriate post-processing. The developed fatigue prediction
methodology can be applied for SLM structures to help reduce testing effort.
Finally, the essential aspects, still need to be investigated to fully exploit the
potential of SLM technology, are highlighted
Current Trends in Friction Stir Welding (FSW) and Friction Stir Spot Welding (FSSW)
No full textThis book provides an overview of friction stir welding and friction stir spot welding with a focus on aluminium to aluminium and aluminium to copper. It also discusses experimental results for friction stir spot welding between aluminium and copper, offering a good foundation for researchers wishing to conduct more investigations on FSSW Al/Cu.
Presenting full methodologies for manufacturing and case studies on FSSW Al/Cu, which can be duplicated and used for industrial purposes, it also provides a starting point for researchers and experts in the field to investigate the FSSW process in detail.
A variant of the friction stir welding process (FSW), friction stir spot welding (FSSW) is a relatively new joining technique and has been used in a variety of sectors, such as the automotive and aerospace industries. The book describes the microstructural evolution, chemical and mechanical properties of FSW and FSSW, including a number of case studies