Academic literature on the topic 'Vibrace trubek'
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Dissertations / Theses on the topic "Vibrace trubek"
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Bartošek, Nikola. "Analýza potíží výměníku tepla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-232124.
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The master thesis is focused on analysis of specific cross-flow in-line tube bundle heat exchanger which deals with significant operational problems. Thermal, hydraulic and vibration calculation analysis of selected parts of the heat exchanger is performed based on CFD flow distribution results. Calculation is performed by using Maple software. Thermal and hydraulic calculations are compared with results obtained by commercial software HTRI.
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Knotek, Jiří. "Ohybové vibrace hnacího ústrojí nákladního vozidla 8x8." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230478.
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The aim of this thesis is an analysis of bending vibrations of the heavy duty truck transmission and a design of construction modifications. The next target is to evaluate the contribution of the construction modification. In the thesis is also performed analysis of shaft support stiffness.
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Kučera, Pavel. "Mechatronický přístup v dynamice vozidel." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-234270.
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This theses deals with mechatronic approach to a vehicle dynamics. It is divided into two main parts. There are prepared vibration analysis, measurement and analysis of functions of truck powertrain in the first part. The second part describes the creation of computational models allowing to simulate driving conditions, vibrations of the vehicle and its extension for the development of mechatronic systems. There are shown different driving modes to control created algorithm of mechatronic system. The main tool for the development of mechatronic systems is the created simulator of vehicle enabling testing of computational models in real time.
Books on the topic "Vibrace trubek"
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van Es, Bart. Introduction. Oxford University Press, 2016. http://dx.doi.org/10.1093/actrade/9780198723356.003.0001.
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What is a Shakespearean comedy? Nearly half of Shakespeare’s plays could be described as comedies of some kind, but more restrictive criteria would whittle the number to just half a dozen true, festive Shakespearean comedies. The ‘Introduction’ describes how Shakespeare’s writing would have been influenced by the vibrant culture of commercial public theatre that he encountered in London, which drew on two traditions: the classical tradition of the grammar schools and the less structured jesting and clowning that grew from the morality play. Changes to Shakespeare’s plays after his death in three areas—the depiction of women; the treatment of politics; and the variation of theatrical design—are also considered.
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Newcomb, John Timberman. Young, Blithe, and Whimsical. University of Illinois Press, 2017. http://dx.doi.org/10.5406/illinois/9780252036798.003.0004.
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This chapter challenges the conceptual model dominating histories of modern American poetry from the 1940s, in which political and aesthetic radicalism are seen as mutually exclusive responses to twentieth-century modernity, by analyzing the avant-gardism of The Masses. It considers how The Masses, together with several other little magazines, enriched the New Verse movement by joining and competing with Poetry: A Magazine of Verse as vibrant venues of contemporary American poetry. It explains how The Masses, by putting ideology above artistry, placed itself beyond the pale of true modernism. It argues that the verse published in The Masses was more than just belated sentimentalizing or Marxist sermonizing with no significant role in the emergence of modern poetry. On the contrary, the magazine had a substantial institutional and aesthetic impact upon the New Poetry. The chapter also contends that The Masses's eclectic and iconoclastic poetics of modernity was strongly aligned with the experimental spirit later valorized by historians as modernist.
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Grant, Stuart A., and David B. Auyong, eds. Ultrasound Guided Regional Anesthesia. Oxford University Press, 2016. http://dx.doi.org/10.1093/med/9780190231804.001.0001.
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This clinically based, comprehensive textbook provides a detailed description of the most useful nerve blocks in ultrasound guided regional anesthesia. Four sections cover Basic Principles (including an appendix, “What Block for What Surgery?), Upper Limb Blocks, Lower Limb Blocks, and Trunk and Spine Blocks. The initial chapter provides a review of ultrasound physics that allows the practitioner to understand how to optimize the ultrasound machine to produce the best ultrasound images possible. This foundation, along with the clinical tips and step-by-step techniques for in-plane and out-of-plane needle guidance, make this instructive text useful for practitioners at all levels. The first chapter also includes seven Keys to Ultrasound Success and concludes with a clinical summary of which blocks to perform for specific surgeries or trauma situations. The specific blocks covered in the remaining chapters range from the classic femoral, interscalene, popliteal sciatic, and axillary blocks to more novel blocks such as the adductor canal, selective suprascapular, quadratus lumborum, and PECS blocks. Each block description includes a review of clinical anatomy, indications, positioning, and a step-by-step approach to ultrasound imaging and needle insertion. Ultrasound images are provided in both an unedited, clean version and a companion version that is clearly labeled, allowing the reader to compare the images side by side. Throughout the book, comprehensive photographs of ultrasound images, cadaver dissections, and patient positioning are provided, with vibrant, colorful annotations that significantly add to the clarity of instruction provided.
Book chapters on the topic "Vibrace trubek"
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Lemon, Robert. "Making Sacramento Into an Edible City." In The Taco Truck, 57–76. University of Illinois Press, 2019. http://dx.doi.org/10.5622/illinois/9780252042454.003.0004.
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Chapter 3 investigates Sacramento, California, as a culinary contested landscape. As the city promotes its new urban marketing brand, “The Farm to Fork Capital of America,” to create a new vibrant sense of place, it does so by upgrading downtown to reinforce the farm-to-table concept. Through urban renewal, restaurateurs strive toward regulating food trucks out of the city. As a result, Mexican taco truck owners struggle to remain part of the cultural landscape. This chapter critically examines Sacramento’s marketing campaign--of incorporating agricultural processes into the city’s image--to explore the country-city relationship, as well as how class, culture, and cuisine influence a city’s architecture. It concludes by presenting the definition of gastronomic gentrification.
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Meizel, Katherine. "The Journey." In Multivocality, 137–58. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190621469.003.0007.
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Chapter 6 discusses the ways in which four transgender singers understand their relationships with voice in extremely individual ways, and how shifts in vocality impact their senses of identity. Each singer who chooses transition—medically assisted or not—lives the process uniquely. Vocality has served different functions and generated different meanings for each of these singers, whose experiences collectively underline the idea of “transition” as an ongoing journey rather than a destination. This chapter presents the multivocal nature of transvocality not as merely double-voicednessand not inevitably about leaving one voice and one identity entirely behind for a newer, “truer” one. Instead, it is a space in which a fluid continuum of selfness, embodied and performed, vibrates differently in every throat.
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Mulgan, Geoff. "Capitalism’s Critics." In The Locust and the Bee. Princeton University Press, 2015. http://dx.doi.org/10.23943/princeton/9780691165745.003.0005.
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This chapter examines the consistent criticisms that have been made of capitalism over two centuries and that continue to be made. They have damned capitalism as a conspiracy of the powerful; as the mindless enemy of mindful reflection; as the destroyer of true value, whether in nature or culture; as the enemy of community and social bonds; and as being against life. This last point shows just how different capitalism is from the market. Where markets are full of life and social interaction, the places where capitalist power is most concentrated can be the opposite of life. Dull and soulless central business districts, automated factory production lines, or the grimly abstract headquarters of global banks embody an aesthetic that runs counter to the vibrant, variegated patterns of living things like forests or coral reefs.
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Shetty, Krishna Prasad. "Responsible Global Leadership." In Innovation and Shifting Perspectives in Management Education, 194–223. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-1019-2.ch009.
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‘Responsible Leadership' is said to be a gift of ‘Management Education' as these two complement and supplement each other. However, this ‘gift-giving' comes in for serious criticism during times of economic crisis, corporate scandals, and ethical violations. The perception that management education ensures responsible global leadership is being questioned. There is a growing demand to re-vitalize management education and make it more meaningful, ethical and beneficial to the global society than just as a status-booster degree with a managerial tool-kit. The B-schools feel the pressure to shift their focus from producing such ‘tool-kit managers' and redefine themselves as centers for responsible leadership development. The ethical challenge in management education for global leadership and sense making sustainable development is the focus of this study. Relevant literature reviews and survey responses show optimism that the dream of passionate and visibly responsible global leadership can come true with vibrant industry-academia association in ethically healthy climate.
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Conn, Steven. "Introduction." In Nothing Succeeds Like Failure, 1–13. Cornell University Press, 2019. http://dx.doi.org/10.7591/cornell/9781501742071.003.0001.
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This introductory chapter provides an overview of American business schools. While at one level business schools stand as of a piece of the way American universities have grown and evolved since the end of the Civil War, they stand apart from the rest of higher education in three, interconnected ways. First, they have consistently disappointed even their most enthusiastic boosters—failing to develop a definition of professional business education, failing to develop a coherent, intellectually vibrant body of knowledge, unable to agree on what the raison d'être of business schools ought to be—to an extent simply not true of any other academic pursuit. Despite this, of course, business schools have flourished on U.S. campuses and continue to do so. Second, the late nineteenth-century revolutions in higher education fostered a change in how universities were funded and governed. For the businessmen who now presided over higher education, a business school on their campus might hold a special place in their hearts. Finally, business schools serve as the handmaids to corporate capitalism in the United States in a way that no other campus enterprise does.
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Mitchell, Graham. "Respiration." In How Giraffes Work, 261–91. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780197571194.003.0012.
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This chapter discusses the respiratory system of giraffes. The respiratory system supplies oxygen, removes of carbon dioxide and produces the airflow needed to make sounds. Giraffes do not have the velocity of airflow through the airways to vibrate vocal cords sufficiently to generate sounds able to be heard by humans but can produce sounds able to be heard by giraffes. Air reaches alveoli for gas exchange through a long trachea, which is relatively narrow (~4 cm in diameter). Dead space volume is large. A short trunk and rigid chest wall reduce the capacity of the thorax and consequently lung volume is small. Respiratory rate is low (~10 min-1), but tidal volume is relatively big, and alveolar ventilation rate (VA; ~60 L min-1) delivers sufficient air despite the large dead space volume. Laryngeal muscles act to prevent food from entering the trachea a process controlled by the (short) superior and (long) inferior (recurrent) laryngeal nerves. Air that has been delivered to alveoli comes into contact with pulmonary artery blood (=cardiac output, Q; ~40 L min-1). The VA: Q ratio is ~1.5 (cf 0.8 in humans). Gas exchange occurs by diffusion. The surface area for diffusion is related to the number of alveoli which increase in number during growth from ~1 billion in a newborn giraffe to 11 billion in an adult. Gas carriage of oxygen and carbon dioxide is a function of erythrocytes which are small (MCV = 12 fL) but numerous (12 × 1012 L-1) and each liter of blood contains ~150 g of hemoglobin.
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Allevato, Eugene, and Joan Marques. "Brazil." In Advances in Finance, Accounting, and Economics, 55–72. IGI Global, 2014. http://dx.doi.org/10.4018/978-1-4666-6224-7.ch004.
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Brazil is globally known for many reasons, varying from its sizzling Copacabana beach to its immense Maracana stadium. It is revered as the birthplace of world-famous soccer players such as Pele, Garrincha, Tostao, Socrates, and Ronaldo, and envied for its eye-popping carnival suits and mesmerizing samba dancers, but there is much more to this country. When considered from a business perspective, Brazil surfaces as one of the four most promising global economies, along with the other BRIC nations of Russia, India, and China, but how much of this vibrant economic picture is true? Having gained independence in the 19th century, there is much to be said about Brazil's current internal economic climate and social system. This chapter takes a less-traveled road in its review of Brazil. By examining this nation from the inside out, a less frequently presented, vulnerable image of this gigantic country is presented. Brazil's relationships with multinationals and with trading partners are reviewed against the backdrop of its lacking growth in national standard of living and its poor primary education system. Brazil is reviewed as the home of impressive industries, its ongoing technological dependency on other nations, and its performance as a supplier of natural resources to many industrial powers.
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Ittzés, Tamás. "There Is No Such Thing as Sound Production, or Sound=Release – The Importance of Natural Movement and Its Teaching in Violin Playing." In Studies in Music Pedagogy - The Methodological Revitalisation of Music Education. University of Debrecen Faculty of Music, 2020. http://dx.doi.org/10.5434/9789634902263/16.
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This study details an approach which, in a certain respect, simplifies violin playing and teaching in the extreme. Creating a sound is based on a very simple rule: the sound = release. Release is preceded by tension, which is released with the sounding of the note. This is true on every level, in every direction. This general rule (or view) helps to make violin playing, the sounds created relaxed, natural and beautiful. The study shows step by step, how the necessary active tension comes into being and then how it is released, how and in what forms performers can use gravity. The main elements of this process are the posture of the body and the instrument, the movements of the arms and the joints (shoulder/armpit/upper arm. elbow/lower arm, wrist/back of the hand/palm and fingers) in their natural direction, the positions of the left hand, touch and vibrato, the relationship of the bow to the string, the use of bowing positions and right bow division, and strokes. Without the appropriate teaching of these no mechanism can be established and because of these deficiencies many a talent has been lost unable to even approach their own boundaries and unable to ever become a professional player. Keywords: sound production, release, natural mechanism, freedom, gravitation, violin
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Bennett, Peggy D. "Musicality in every subject." In Teaching with Vitality. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190673987.003.0036.
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Expressiveness, flow, and emotion, make music charming, appealing, and moving. Those manifestations are what make music an art. They are what make music musical. When music is stripped of its musicality in order to study it, we can lose the very aesthetic that makes it worthy of listening, performing, and studying (Bennett, 2016). The same is true for nearly any other school subject. Passion for a subject and desire to share that passion are likely what motivated us to become teachers. It should be no surprise, then, that the quality of the subject matter in our classrooms can influence our vitality for teaching and students’ vitality for learning. Sometimes it is our quest to teach information about our subject that diminishes the very qualities that inspire our passion for it. What a paradox: the way we teach a subject can cause students to lose interest in learning it! How does this happen? Prioritizing expressiveness and curiosity can revitalize us. When we strip enjoyment and fascination from learning and focus only on mechanics or information, we may be strangling interest and aesthetic appeal for our students and for ourselves. What can we do? • Create lessons that capture students’ interest in learning. Find “hooks” that catch their curiosity. • Immerse students in a subject’s applicability to and connections with their daily lives. • Infuse lessons with quirky or humorous samples of ways the subject can be understood or used. Passion for any subject, the musicality of it, can be ignited or extinguished in schools. Teaching subjects in lifeless ways can wear on our spirits. Let’s give ourselves permission to highlight aspects of our subjects we enjoy and commit ourselves to teaching those subjects with integrity. When we teach what we love and love what we teach, we are vibrant . . . and so is learning.
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Bennett, Peggy D. "Resilience." In Teaching with Vitality. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190673987.003.0073.
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Troubles are inevitable and necessary in schools. Yet when we are in the midst of them, we can feel hopeless and chronically agitated. Key here is our resilience: how quickly and easily do we bounce back from turmoil? A basketball can provide a rich metaphor for bouncing back. Compression is key to a basketball functioning properly. An underinflated basketball has little resilience, does not bounce well, and may not behave or look like a basketball. The same is true for teachers. Very likely we will get sick, have our feelings hurt, not measure up to expectations. Very likely. So the key is not to dodge these silent missiles that come our way. The key is to learn how to be resilient, to bounce back, to regain our composure. Like a basketball, those within schools can expect to have times of inflation and deflation. A total absence of conflict and disagreement is not an option. Both are natural and necessary. Do you know what deflates or causes you to be underinflated? Fatigue, conflict, discord, confusion, loss of trust, fear, disincentive, sense of failure. Do you know what inflates you, what restores your compression? Nutrition, hydration, exercise, conversation with a friend, inspiring ideas, change of routine, listening to music, laughing, feeling powerful and vibrant. Adversity is not what depletes us. Absence of resilience does. If we were able to view major or minor difficulties as natural, normal, and valuable events, would our responses to them change? Would we be able to accept rather than resent them? Being hostile toward any of life’s difficulties only amplifies our discomfort, and we end up at war with ourselves, arguing with our lives rather than living them.
Conference papers on the topic "Vibrace trubek"
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Eastman, Andrew, Jacob Kiefer, and Mark Kimber. "Thrust Measurements and Flow Field Analysis of a Piezoelectrically Actuated Oscillating Cantilever." In ASME 2012 Fluids Engineering Division Summer Meeting collocated with the ASME 2012 Heat Transfer Summer Conference and the ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/fedsm2012-72135.
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Although not identical to the motion employed by nature’s swimmers and flyers, the simple harmonic oscillations of cantilever-like structures have been shown to provide efficient low power solutions for applications ranging from thermal management to propulsion. However, in order to quantify their true potential, the resulting flow field and corresponding thrust must be better understood. In this work, a thin, flexible cantilever is actuated via a piezoelectric patch mounted near its base and caused to vibrate in its first resonance mode in air. The flow field is experimentally measured with Particle Image Velocimetry while the thrust produced from the oscillatory motion is quantified using a high resolution scale. The trends observed in the data are captured using an oscillating Reynolds number and a clear relationship is defined between the operating parameters and the resulting thrust. Two dimensional flow fields are extracted from the x-y and y-z planes, and are primarily used to motivate future geometry and sidewall configurations that could greatly enhance the thrust capabilities of the cantilever by directing the flow downstream in a more effective manner.
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Rodriguez, Luis, Juan Uribe, P. A. Munoz, Roberto Parrado, and Nestor Sanabria. "Petroleum Exploration Using New Technologies in 3D Seismic Operations in Arctic Environment - North Slope Alaska." In ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/omae2018-78064.
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Oil exploration in arctic regions is a very complex activity taking place in a sensitive environment, highlighted by social, wildlife and extreme weather conditions restricting operations to a very limited time window based on the opening of the Tundra season regulations which assesse the quality of the ice and snow coverage over frozen tundra, lakes and seas. Thanks to new technologies, oil exploration in the arctic environment takes a great steps in 3D seismic acquisition methods passing from cable recording equipment and the dependence of sensor connectivity to a recording center and replacing this system with a very versatile system of wireless receivers units equipped with GPS positioning and time stamp recording and storing the seismic data “in situ”. This new technology has allowed a high unit count of light receivers to operate in extreme conditions, which in the past was practically impossible given the limitations of the logistical support to carry out this type of operations in remote and difficult access areas. Definitely this technological development has allowed Repsol to explore a larger surface area in a single winter season acquiring high resolution seismic data that allows obtaining high quality images with better geophysical attributes. Seismic sources have also undergone a notable evolution through the use of high productivity techniques of vibrating trucks moving from a set of multiple vibrators to a single vibrator emission getting up to date simultaneous source acquisitions which allows recording more information without waiting for a second set of vibrators or single vibroseis truck to start shaking to emit energy to the ground. The ability to vibrate at the same time with many sets of single vibrators allows operation on frozen sea either with grounded ice or vibrating on floating ice expanding the exploration boundary to the open sea zones. The new technology has made it possible for Repsol to improve the operational capability of the crew without increasing the number of people or increasing the logistical support required to operate in remote and difficult access areas. This technological advance has allowed the improvement of the quality of oil exploration using 3D seismic techniques reducing the price per recorded trace or per surface source, increasing the possibility to acquire larger surfaces and better seismic data in a single winter season window. More importantly, these technologies have allowed affordable oil exploration with a high respect for the communities, the wildlife and the environment.
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Sracic, Michael W., Jordan D. Petrie, Henry A. Moroder, Ryan T. Koniecko, Andrew R. Abramczyk, and Kamlesh Suthar. "Acoustic Pressure Fields Generated With a High Frequency Acoustic Levitator." In ASME 2017 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/imece2017-71849.
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Acoustic levitation is an advantageous particle positioning mechanism currently employed for applications of x-ray spectroscopy and micro-material manufacturing[1], [2]. By levitating a particle using only acoustic pressure waves, one eliminates the need for a container or other physical structure which may contaminate the specimen. Unfortunately, the pressure field generated by a standing acoustic wave is susceptible to periodic instabilities, and a particle that is levitated in this field tends to vibrate. The amplitude of the vibration is largest in the directions that are orthogonal to the axis in which the acoustic wave is generated. Therefore, by generating additional acoustic waves in each orthogonal axis, the vibration amplitude of the levitated particle is significantly reduced. The authors have shown this phenomenon to be true in a previous study[3]. In this paper, the authors explore the details of the pressure field that is generated with the device. A single degree-of-freedom relationship is developed between the acoustic field pressure, the location of the levitated particle, and the mechanical vibration needed to produce levitation. In order to levitate a 100 micrometer diameter water droplet at 55 kilohertz, the calculations suggest that the transducer must achieve an average surface vibration amplitude of at least 6.43 micrometers. This mechanical vibration must produce a root means-squared pressure amplitude of 933 Pascal. Under these conditions, the particle will levitate approximately 0.4 millimeters below a zero pressure node. To validate the use of the single degree of freedom relationships and to explore the acoustic field for one, two, and three-axis levitation, the authors designed and prototyped an acoustic levitator capable of generating standing waves in three orthogonal directions. Using a simple electrical control circuit, the acoustic wave transducers of each axis can be turned on individually or simultaneously. An experiment was developed to measure the pressure of the acoustic field using a microphone. Preliminary pressure magnitude results were measured for one-axis levitation along the center of the vertical axis of the levitator. The measurements suggest that the theoretical development provides a valid first approximation for the pressure magnitude and required mechanical vibration amplitude.
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Aggarwal, Vaishali. "Smart Cities in India: branded or brain-dead?" In 55th ISOCARP World Planning Congress, Beyond Metropolis, Jakarta-Bogor, Indonesia. ISOCARP, 2019. http://dx.doi.org/10.47472/rian9466.
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The notion of ‘smart cities’ is increasingly visible in discourses on the future of cities but Change is coming to transportation, whether we are ready for it or not. But how sustainable and digital innovation can unlock better people health and well-being, enhance safety and security and provide seamless mobility experiences. It can be argued that smartening the mobility infrastructure enables the citizens to make informed decisions, and this is indeed true- if done well, but it has a big “if.” This research engages with the key drivers of change and provides affirmative aspirations for mobility in the not-so-distant future in order to facilitate conversations about change. However, the development of possibilities (scenarios) for the government policies and business innovation is dependent on the advanced technology and socio-economic values, which are embedded in the context and culture. The research paper aims to visualize through foresight by design, plausible alternatives of sustainable future for passenger transport in Delhi to stimulate sustainable innovation developments for transportation and analyse the present innovative influences for smart mobility in Delhi to accelerate the adoption. The first part of the paper analyses how do urban planners use the discourse of smart cities and how it has defined in India then later suggest future scenario for the future which will empower users, changing mobility models and transforming eco-system where intelligent connectivity would unite varied rage of emerging technologies to enable smarter, healthier and more resilient and economically vibrant urban life. This research considers smart mobility by outlining current challenges, suggesting technological, infrastructural and policy solutions and distilling explorations of the future into a series of ‘user journeys.’ It seeks to answer if ‘branding of technology’ can be used as a tool to create a new identity for mobility of Delhi or ‘upgrade’ the existing situation. How can the context of Delhi be decoded to describe the perceptions of the people?
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Raposo, Celso, Olav Fyrileiv, and Antonio Pereira. "On the Challenges With Pipeline Free Spans in Operational Phase." In ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/omae2014-23403.
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Free span assessment has more and more become an important part of modern pipeline design. The reason for this is partly that the remaining hydrocarbon reservoirs are located in more challenging places, e.g. with very uneven seabed. Another explanation is that the pipeline design codes a few decades ago did not allow for vibrating free spans, while the modern, state-of-the-art pipeline codes, such as DNV-OS-F101 “Submarine Pipeline Systems” (2013) and its Recommended Practices, opens for long spans that are allowed to vibrate as long as the structural integrity is ensured. In presence of non-cohesive soils and high on-bottom flow velocities significant free span development may occur over the design life, e.g. due to scouring. Such spans may be associated with a fatigue life capacity less than the design life if the spans are assumed stationary. For non-stationary spans with occasional long span lengths this may not be true since the criticality is strongly linked to the persistence of long spans and the prevailing environmental condition. A realistic fatigue assessment must account for the history of the span (i.e. stress cycles encountered for a critical weld) including predictions into the future development. High costs related to span intervention puts focus on minimizing these costs while still ensuring integrity of the pipeline with respect to vortex induced vibrations (VIV) and associated fatigue damage. On the other hand the potential costs related to fatigue failure of a pipeline (recovery costs, economical loss and environmental consequences) are enormous. Therefore it is essential to ensure that the probability of failure for free spans is within acceptable limits. One frequent challenge faced with old pipelines in operations survey reports are that they report several free spans. Old pipelines were not designed to allow any vibration and usually there is scanty information about different parameters such as soil conditions, operational parameters, lay tension, environmental data, etc., thus it’s difficult to determine whether it’s necessary to intervene the span or not. State-of-the-art free span codes are deterministic in their nature. If the new codes are used to evaluate such old pipeline spans, considering all the before mentioned uncertainties in the input parameters, this would eventually lead to over conservative very low time to failures. The outcome will be that many spans need to be fixed immediately or should have failed already. Such a situation leads to a mistaken conclusion about the conservatism of the codes and not on the way they were applied. This paper discusses some of the challenges often seen with free spans during the operational phase. The objective of the paper is to demonstrate that for in-service pipelines the lack of reliable information about the free spans is the main source of commonly low life encountered and not the methodology used to evaluate the free span. Some of these challenges are discussed in detail and potential ways forward are outlined.