Academic literature on the topic 'Intermediate check'
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Journal articles on the topic "Intermediate check"
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Amankwa, G. A., S. Mishra, A. D. Shearer, C. Saude, D. L. Van Hooren, and M. D. Richmond. "CTH144 flue-cured tobacco F1 hybrid." Canadian Journal of Plant Science 99, no. 6 (December 1, 2019): 966–68. http://dx.doi.org/10.1139/cjps-2018-0328.
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CTH144 is a new flue-cured tobacco (Nicotiana tabacum L.) hybrid recommended for commercial release in Canada. The cured leaf quality of CTH144 was superior to both check varieties Delgold and CT157. The yield potential of CTH144 was intermediate compared with the checks. As a result, the economic return of CTH144 is superior to both check varieties. CTH144 has resistance to Tobacco Mosaic Virus. CTH144 is adapted to the tobacco-growing areas of southwestern Ontario.
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Turner, Robert G. "Double Checking the Cross-Check Principle." Journal of the American Academy of Audiology 14, no. 05 (May 2003): 269–77. http://dx.doi.org/10.1055/s-0040-1715737.
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The cross-check principle was proposed by Jerger and Hayes over 20 years ago. Actually, the cross-check principle consists of a concept and a specific test protocol. The concept, that one test result confirms another test result, is still in use. Their specific protocol is essentially forgotten. The cross-check protocol they described, however, differs from more traditional test protocols. From the design of their cross-check protocol we can extract two unique testing strategies. The first strategy requires agreement between both tests before a decision can be made. This strategy can significantly improve testing performance; however, the "cost" of this strategy is a population of individuals for whom no decision is possible because the two tests disagree. The cross-check protocol uses a third test when the first two tests disagree, Essentially, the cross-check protocol employs an intermediate criterion, the second unusual strategy. Somewhat surprisingly, this intermediate criterion has the ability to simultaneously increase protocol hit rate and decrease protocol false alarm rate relative that of the individual tests in the protocol. The more traditional protocol criteria cannot do this. Each strategy offers some interesting and important advantages and should be considered by audiologists when using multiple tests.
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Cuthbert, R. D., R. M. DePauw, R. E. Knox, A. K. Singh, B. McCallum, and T. Fetch. "AAC Viewfield hard red spring wheat." Canadian Journal of Plant Science 99, no. 1 (February 1, 2019): 102–10. http://dx.doi.org/10.1139/cjps-2018-0147.
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AAC Viewfield hard red spring wheat (Triticum aestivum L.) has a grain yield significantly higher than the check cultivars Katepwa and Lillian and is similar to Carberry. AAC Viewfield matures significantly later than Katewpa and Lillian but is similar to Carberry. AAC Viewfield has an awned spike, a low lodging score (indicative of strong straw), and significantly shorter plant stature than all checks. AAC Viewfield expressed resistance to prevalent races of yellow rust and stem rust, moderate resistance to leaf rust and common bunt, and intermediate resistance to Fusarium head blight. AAC Viewfield has quality attributes within the range of the check cultivars and is eligible for grades of Canada Western Red Spring wheat.
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Amankwa, G. A., S. Mishra, A. D. Shearer, R. Brammall, and D. L. Van Hooren. "CTH8 flue-cured tobacco hybrid." Canadian Journal of Plant Science 94, no. 2 (March 2014): 461–63. http://dx.doi.org/10.4141/cjps2013-259.
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Amankwa, G. A., Mishra, S., Shearer, A. D., Brammall, R. and Van Hooren, D. L. 2014. CTH8 flue-cured tobacco hybrid. Can. J. Plant Sci. 94: 461–463. CTH8 is a new flue-cured tobacco (Nicotiana tabacum L.) hybrid recommended for commercial release in Canada. It has superior grade index compared to the check varieties Delgold and CT157, and its yield potential is intermediate between the two checks.
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Fox, S. L., D. G. Humphreys, P. D. Brown, T. F. Townley-Smith, B. D. McCallum, T. G. Fetch, D. A. Gaudet, J. G. Menzies, J. A. Gilbert, and J. S. Noll. "KANE hard red spring wheat." Canadian Journal of Plant Science 87, no. 4 (October 1, 2007): 889–94. http://dx.doi.org/10.4141/cjps06043.
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KANE is a hard red spring wheat that meets the end-use quality and kernel visual distinguishability specifications of the Canada Western Red Spring market class. KANE was found to be adapted to the wheat-growing regions of Manitoba and eastern Saskatchewan from the data provided by the Central Bread Wheat Cooperative registration test in 2003–2005. In comparison with the check cultivars Katepwa, McKenzie, CDC Teal, AC Barrie, and Superb, the overall grain yield of KANE was similar to the high yield checks McKenzie and Superb. Compared with the highest yielding check McKenzie, KANE was 1.7 d later maturing, was 6 cm shorter, had stronger straw, and was significantly higher (1.1 kg hL-1) in test weight. KANE is resistant to the prevalent races of leaf rust and stem rust. Resistance to common bunt and loose smut was intermediate, being similar to CDC Teal and McKenzie, respectively. Resistance to fusarium head blight was similar to AC Barrie. KANE has good preharvest sprouting resistance with similar or lower sprouting scores compared to the best check in 4 out of 5 yr of testing. End-use quality tests showed that KANE had a 0.7% higher flour extraction rate than the best checks and was within the range of the checks for the other quality traits. Key words: Triticum aestivum L., cultivar description, red spring wheat, test weight, preharvest sprouting, leaf rust
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Shiri, Sepideh, and Hassan Abdilah. "The Influence of Topic Management on the Speaking Ability of Iranian Intermediate EFL Learners." International Journal of Applied Linguistics and English Literature 9, no. 3 (May 31, 2020): 62. http://dx.doi.org/10.7575/aiac.ijalel.v.9n.3p.62.
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In English as a Foreign Language (EFL) settings where English is not the spoken language, Topic Management has been recognised as one of the factors that influence the speaking ability of learners (Du-Babcock, 1999). In Iran, many intermediate EFL learners find it very difficult to manage the speech aspect of the English language. The present study examines the influence of Topic Management on the speaking ability of Iranian intermediate EFL learners. It provides useful insights on teaching speaking skills through Topic Management to improve the speaking ability of learners. In this study, quasi-experimental design was used. 40 intermediate learners were selected and divided into two groups, the Control Group and the Experimental Group. Three tests were administered to obtain data from the participants. These were a proficiency test to check the English proficiency level of the participants, a speaking pre-test to check their speaking ability before the treatment, and a speaking post-test to check their speaking ability after the treatment. The results indicate that Topic Management has an influence on the speaking ability of Iranian EFL learners. That is, the more the student is confident in managing the topic the more he/she is able to sustain the conversation. The study concludes that Topic Management can be a facilitative approach to improving Iranian intermediate EFL learners’ speaking ability.
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Smith, Janette, Jeries Paolo Zawaideh, Hilal Sahin, Susan Freeman, Helen Bolton, and Helen Clare Addley. "Differentiating uterine sarcoma from leiomyoma: BET1T2ER Check!" British Journal of Radiology 94, no. 1125 (September 1, 2021): 20201332. http://dx.doi.org/10.1259/bjr.20201332.
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Although rare, uterine sarcoma is a diagnosis that no one wants to miss. Often benign leiomyomas (fibroids) and uterine sarcomas can be differentiated due to the typical low T2 signal intensity contents and well-defined appearances of benign leiomyomas compared to the suspicious appearances of sarcomas presenting as large uterine masses with irregular outlines and intermediate T2 signal intensity together with possible features of secondary spread. The problem is when these benign lesions are atypical causing suspicious imaging features. This article provides a review of the current literature on imaging features of atypical fibroids and uterine sarcomas with an aide-memoire BET1T2ER Check! to help identify key features more suggestive of a uterine sarcoma.
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Cuthbert, R. D., R. M. DePauw, R. E. Knox, A. K. Singh, T. N. McCaig, T. Fetch, and B. McCallum. "AAC Elie hard red spring wheat." Canadian Journal of Plant Science 96, no. 5 (October 1, 2016): 919–27. http://dx.doi.org/10.1139/cjps-2015-0291.
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AAC Elie hard red spring wheat (Triticum aestivum L.) has grain yield and time to maturity within the range of the checks. AAC Elie has an awned spike, a low lodging score indicative of strong straw, and a short plant stature typical of a semidwarf. These traits were comparable to the check Carberry. AAC Elie expressed resistance to prevalent races of leaf and stem rust, and intermediate resistance to fusarium head blight, yellow rust, common bunt, and loose smut. Compared with the five Canada Western Red Spring checks, AAC Elie has improved flour yield, and lower flower ash. AAC Elie is eligible for grades of Canada Western Red Spring.
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Humphreys, D. G., B. D. McCallum, T. G. Fetch, J. A. Gilbert, O. M. Lukow, J. G. Menzies, P. D. Brown, and S. L. Fox. "Glencross hard red extra strong spring wheat." Canadian Journal of Plant Science 100, no. 1 (February 1, 2020): 121–28. http://dx.doi.org/10.1139/cjps-2019-0191.
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Glencross is a hard red spring wheat (Triticum aestivum L.) adapted to the wheat-growing regions of the Canadian Prairies, particularly where orange blossom wheat midge is a production constraint. Glencross was evaluated in the High Yielding Red Wheat Cooperative Test in 2004, 2005, and 2006. Glencross had grain yield similar to the Canada Western Extra Strong (CWES) checks, Glenlea and CDC Rama, as well as the Canada Western Red Spring check, Superb; however, Glencross was significantly (P < 0.05) earlier maturing than all checks by 3 (Superb) to 4 (Glenlea and CDC Rama) days. Glencross had plant height and lodging scores similar to the CWES checks, Glenlea and CDC Rama, but was significantly taller and had significantly higher lodging scores compared with the CWRS check, Superb. Glencross was moderately resistant to moderately susceptible to leaf rust but was highly resistant to stem rust and loose smut. Glencross showed an intermediate reaction to common bunt and was similar to the susceptible checks for Fusarium head blight. Glencross is the first CWES cultivar with resistance to the orange blossom wheat midge (Setodiplosis mosellana Géhin). Glencross demonstrated end-use quality suitable for all grades of the Canada Western Extra Strong wheat class.
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Huang, Feng Yun, Pan Hao, and Rui Feng Gao. "Design of PLC Sequential Function Chart Based on IEC61131-3 Standard." Applied Mechanics and Materials 325-326 (June 2013): 1130–34. http://dx.doi.org/10.4028/www.scientific.net/amm.325-326.1130.
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According to the requirements of IEC61131-3 standard, the system of Programmable Logic Controller (PLC) using Sequential Function Chart (SFC) as the main programming language is build. Aiming at the requirements of the SFC programming system, the framework of SFC is established, on this basis, a suit of data structure based on Object-Oriented thinking is designed. It describes the data structure of SFC mainly, and in this way, the functions of SFC, including edit, modify and compile, etc, are realized.The syntax check and logic check of SFC are achieved by traveling recursively and iterating the layers of the nested data structure of SFC. After making SFC into intermediate code, eventually the intermediate code is translated into the corresponding object code.
Dissertations / Theses on the topic "Intermediate check"
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Потоцький, Ігор Олексійович. "Методи встановлення інтервалів калібрування еталонів та засобів вимірювальної техніки." Doctoral thesis, Київ, 2020. https://ela.kpi.ua/handle/123456789/32606.
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Робота полягає у розробленні методів визначення інтервалів між калібруваннями (міжкалібрувальних інтервалів) робочих еталонів та засобів вимірювальної техніки, які застосовуються у випробувальних та калібрувальних лабораторіях, спрямована на забезпечення метрологічної простежуваності, точності та достовірності результатів вимірювань. У роботі досліджено можливість контролю відповідності метрологічних характеристик еталонів та засобів вимірювальної техніки встановленим нормам із застосуванням контрольних карт накопичених сум (CUSUM-карт). Проведені дослідження показали, що, незважаючи на здатність CUSUM-карт виявляти навіть незначні зміни метрологічних характеристик засобів вимірювальної техніки, час отримання сигналів може бути досить тривалим. Проаналізувавши затримку сигналів на CUSUM-картах та недоліки, що їх спричинюють, було запропоновано новий метод ковзної регресії на CUSUM-карті. Метод заснований на порівнянні кута нахилу регресійної лінії, проведеної за кількома послідовними точками на карті, з розрахованим гранично допустимим. Показано теоретично та доведено
експериментально, що застосування методу ковзної регресії дозволяє зменшити час затримки сигналу про вихід метрологічних характеристик еталонів чи засобів вимірювальної техніки за встановлені границі. Представлено новий підхід до контролю стану засобів вимірювальної техніки шляхом аналізу СКВ результатів спостережень, що вказує на зменшення їх чутливості. Підхід заснований на ймовірнісному аналізі потрапляння СКВ результатів спостережень в певні діапазони розподілу Пірсона. Введено поняття критичної послідовності точок, виникнення якої вказує на зміну чутливості з часом засобу вимірювальної техніки, та коефіцієнт ефективності, який вказує на доцільність застосування того чи іншого підходу. На основі проведених розрахунків та досліджень запропоновано адаптивний алгоритм виявлення критичної послідовності СКВ-точок, який дозволяє контролювати стан робочих еталонів та засобів вимірювальної техніки, спираючись на отримані СКВ результатів спостережень у контрольних точках. Наведено теоретичне та експериментальне обґрунтування розроблених методів, показано в якому випадку необхідно застосовувати той чи інший метод.
Books on the topic "Intermediate check"
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Zamor, Natacha. Hypoxia During Anesthesia. Edited by Matthew D. McEvoy and Cory M. Furse. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190226459.003.0022.
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In the modern anesthesia machine, there are various safety checks in place to help prevent the delivery of a hypoxic gas mixture to the patient. They include the pin index safety system (PISS), diameter index safety system (DISS), failsafe valve, oxygen-nitrous oxide proportioning system, oxygen supply failure alarm, flowmeter sequence, and, most distally, the oxygen analyzer. The PISS is a feature in the high-pressure system. The DISS, failsafe valve, and oxygen failure alarm are in the intermediate-pressure system. The flowmeters, proportioning system, and oxygen analyzer are in the low-pressure system. This chapter undertakes a discussion of the distinct role of each feature and their limitations.
Book chapters on the topic "Intermediate check"
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Weik, Martin H. "intermediate block check." In Computer Science and Communications Dictionary, 816. Boston, MA: Springer US, 2000. http://dx.doi.org/10.1007/1-4020-0613-6_9369.
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Eilers, Marco, Severin Meier, and Peter Müller. "Product Programs in the Wild: Retrofitting Program Verifiers to Check Information Flow Security." In Computer Aided Verification, 718–41. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-81685-8_34.
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AbstractMost existing program verifiers check trace properties such as functional correctness, but do not support the verification of hyperproperties, in particular, information flow security. In principle, product programs allow one to reduce the verification of hyperproperties to trace properties and, thus, apply standard verifiers to check them; in practice, product constructions are usually defined only for simple programming languages without features like dynamic method binding or concurrency and, consequently, cannot be directly applied to verify information flow security in a full-fledged language. However, many existing verifiers encode programs from source languages into simple intermediate verification languages, which opens up the possibility of constructing a product program on the intermediate language level, reusing the existing encoding and drastically reducing the effort required to develop new verification tools for information flow security. In this paper, we explore the potential of this approach along three dimensions: (1) Soundness: We show that the combination of an encoding and a product construction that are individually sound can still be unsound, and identify a novel condition on the encoding that ensures overall soundness. (2) Concurrency: We show how sequential product programs on the intermediate language level can be used to verify information flow security of concurrent source programs. (3) Performance: We implement a product construction in Nagini, a Python verifier built upon the Viper intermediate language, and evaluate it on a number of challenging examples. We show that the resulting tool offers acceptable performance, while matching or surpassing existing tools in its combination of language feature support and expressiveness.
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Wu, Wenhao, Jan Hückelheim, Paul D. Hovland, and Stephen F. Siegel. "Verifying Fortran Programs with CIVL." In Tools and Algorithms for the Construction and Analysis of Systems, 106–24. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-99524-9_6.
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AbstractFortran is widely used in computational science, engineering, and high performance computing. This paper presents an extension to the CIVL verification framework to check correctness properties of Fortran programs. Unlike previous work that translates Fortran to C, LLVM IR, or other intermediate formats before verification, our work allows CIVL to directly consume Fortran source files. We extended the parsing, translation, and analysis phases to support Fortran-specific features such as array slicing and reshaping, and to find program violations that are specific to Fortran, such as argument aliasing rule violations, invalid use of variable and function attributes, or defects due to Fortran’s unspecified expression evaluation order. We demonstrate the usefulness of our tool on a verification benchmark suite and kernels extracted from a real world application.
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Jacob, Heinz Jürgen, Monika Jacob, and Bodo Christ. "The Early Development of the Intermediate Mesoderm in the Chick." In Somites in Developing Embryos, 61–68. Boston, MA: Springer US, 1986. http://dx.doi.org/10.1007/978-1-4899-2013-3_5.
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Alagumalai, Sivakumar, and Kok-Aun Toh. "Web-Based Assessment." In Web-Based Learning and Teaching Technologies, 246–56. IGI Global, 2000. http://dx.doi.org/10.4018/978-1-878289-60-5.ch015.
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Meaningful learning is a positive outcome of successful teaching. Teaching can be fruitless when no learning occurs. Assessment is the intermediate check between good teaching and learning. Assessment includes both the qualitative and quantitative checks for successful learning and appropriate assimilation and integration of knowledge and experiences. This chapter reviews current trends in assessment with particular reference to Web-based techniques. Measurement models related to assessment are discussed. Current researches on Web-based computer adaptive testing utilizing common-gateway interfaces are highlighted. It also discusses technical details of how Web-based assessment are set up and implemented. Details of communication technologies currently using Web-based techniques are highlighted. This chapter concludes with a review of current research and methods in current practice on Web-based assessment techniques. Plausible uses of newer software and the requirements for parallel hardware developments are raised. The final section also argues that if teaching methods and pedagogies are changing and being modified due to developments in information and communication technologies, it would be necessary to relook at assessment. Web-based assessment presents the optimal mode for testing authentic learning and has the potential to be developed as the most common way of testing, replacing paper-and-pencil tests in the future.
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Watt, Gary. "13. Maintenance and advancement." In Equity & Trusts Law Directions, 300–319. Oxford University Press, 2019. http://dx.doi.org/10.1093/he/9780198804703.003.0013.
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Without assuming prior legal knowledge, books in the Directions series introduce and guide readers through key points of law and legal debate. Questions, diagrams and exercises help readers to engage fully with each subject and check their understanding as they progress. Under the Trustee Act 1925, trustees have the power to make payments out of the trust income for the maintenance of infant beneficiaries, as well as the power to make payments out of trust capital for the advancement and benefit of both infant and adult beneficiaries. However, the express terms of the trust instrument can exclude or modify these provisions. This chapter deals with maintenance and advancement of trust beneficiaries. It examines the extent of the statutory powers of maintenance and advancement, how the statutory powers are excluded or modified by the express terms of the settlement and a valid exercise of the powers of maintenance and advancement. The chapter also considers maintenance with respect to gifts carrying intermediate income, class gifts, tax considerations, perpetuities, and maintenance out of capital money, along with the meaning of ‘benefit’, exercise of discretion to make an advancement and contrary intention in the trust instrument.
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Watt, Gary. "13. Maintenance and advancement." In Equity & Trusts Law Directions, 298–317. Oxford University Press, 2021. http://dx.doi.org/10.1093/he/9780198869382.003.0013.
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Without assuming prior legal knowledge, books in the Directions series introduce and guide readers through key points of law and legal debate. Questions, diagrams and exercises help readers to engage fully with each subject and check their understanding as they progress. Under the Trustee Act 1925, trustees have the power to make payments out of the trust income for the maintenance of infant beneficiaries, as well as the power to make payments out of trust capital for the advancement and benefit of both infant and adult beneficiaries. However, the express terms of the trust instrument can exclude or modify these provisions. This chapter deals with maintenance and advancement of trust beneficiaries. It examines the extent of the statutory powers of maintenance and advancement, how the statutory powers are excluded or modified by the express terms of the settlement and a valid exercise of the powers of maintenance and advancement. The chapter also considers maintenance with respect to gifts carrying intermediate income, class gifts, tax considerations, perpetuities, and maintenance out of capital money, along with the meaning of ‘benefit’, exercise of discretion to make an advancement and contrary intention in the trust instrument.
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Pradhan, Sonali, Mitrabinda Ray, and Srikanta Patnaik. "Coverage Criteria for State-Based Testing." In Research Anthology on Agile Software, Software Development, and Testing, 1222–44. IGI Global, 2022. http://dx.doi.org/10.4018/978-1-6684-3702-5.ch061.
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State-based testing (SBT) is known as deriving test cases from state machines and examining the dynamic behaviour of the system. It helps to identify various types of state-based faults within a system under test (SUT). For SBT, test cases are generated from state chart diagrams based on various coverage criteria such as All Transition, Round Trip Path, All Transition Pair, All Transition Pair with length 2, All Transition Pair with length 3, All Transition Pair of length 4 and Full Predicate. This article discuses a number of coverage criteria at the design level to find out various types of state-based faults in SBT. First, the intermediate graph is generated from a state chart diagram using an XML parser. The graph is traversed based on the given coverage criteria to generate a sequence of test cases. Then, mutation testing and sneak-path testing are applied on the generated test cases to check the effectiveness of the generated test suite. These two are common methods for checking the effectiveness of test cases. Mutation testing helps in the number of seeded errors covered whereas sneak-path testing basically helps to examine the unspecified behavior of the system. In round trip path (RTP), it is not possible to cover all paths. All transition is not an adequate level of fault detection with more execution time compared to all transition pair (ATP) with length 4 (LN4). In the discussion, ATP with LN4 is the best among all coverage criteria. SBT can able to detect various state-based faults-incorrect transition, missing transition, missing or incorrect event, missing or incorrect action, extra missing or corrupt state, which are difficult to detect in code-based testing. Most of these state-based faults can be avoided, if the testing is conducted at the early phase of design.
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Cohn, Margit. "Keeping the Internal Tension Under Check." In A Theory of the Executive Branch, 289–320. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198821984.003.0011.
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Concerned with the role of the judiciary as a constraining agent of fuzzy law, the chapter is laid out in two layers. First, in light of the special problems attached to reliance on fuzzy law, it advances arguments that call for enhanced review in this context. Secondly, the chapter joins the ongoing general debate over the role of the judiciary in the shaping of the public sphere. The argument for active review is based both on the principles reflected in the rule of law ideal, and on an argument from governance. Setting judicial review in a framework that seeks to enhance participation, the judiciary, stripped of accusations of supremacy over all other forms of decision-making, operates as an intermediator by offering members of society, especially those who do not have direct access to government corridors, an additional forum for voicing their concerns and thereby contributing to public deliberation over all contested aspects of social and political life.
Conference papers on the topic "Intermediate check"
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Doiron, Ted. "Dimensional Metrology, Intermediate Precision and Uncertainty." In NCSL International Workshop & Symposium. NCSL International, 2015. http://dx.doi.org/10.51843/wsproceedings.2015.05.
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Uncertainty has proven difficult to implement in calibrations labs. The subject has advanced mathematics and statistics that are often needed for scientific research, but are seldom needed to develop uncertainty budgets for routine calibrations. There is, however, a second path to uncertainty that does not require such mathematical skills, only patience. This method, using check standards to sample the sources of variability is actually part of the GUM, albeit a small part.
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Laney, Matthew, and Ronald Farrell. "Piston-Lift Check Valve Flow Verification Using CFD." In ASME 2018 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/pvp2018-84672.
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Computational Fluid Dynamics (CFD) is increasingly being used as a reliable method for determining flow characteristics of a wide range of flow situations. This paper presents an extension of paper PVP2017-66269, “Check Valve Flow and Disk Lift Simulation Using CFD” [1], and utilizes some of the same concepts to characterize flow through piston-lift check valves. The previous example considered a swing check valve involving rotational movement; this example considers a vertical lift piston check valve involving translational movement. Specifically, CFD was used to determine valve flow coefficients (CV) as a function of disk lift position as well as to determine the flow rate required to achieve full open or predict intermediate disk lift positions. The CFX application, which is part of the ANSYS suite of finite element software, was used to determine the flow characteristics. As presented in PVP2017-66269, balancing flow-induced forces on the check element and considering the disk assembly weight, the valve lift behavior can be predicted. Results from the CFX analysis were compared to recent test results of a skirted disk-piston check valve and previous test results of a standard disk-piston check valve. The results showed good agreement in most cases. This validates that flow characteristics across valves with different types of check elements at different disk lift positions can be reliably predicted using CFD analysis. It is important to note that while the test results and CFD analysis showed good agreement, it was vital that actual testing be performed in order to validate the approach. This follows the recommendation outlined in the previous paper.
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Farrell, Ronald, L. Ike Ezekoye, and Mark Rain. "Check Valve Flow and Disk Lift Simulation Using CFD." In ASME 2017 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/pvp2017-66269.
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Computational Fluid Dynamics (CFD) is increasingly being used as a reliable method for determining flow characteristics of a wide range of flow situations. This paper presents an investigation on the application of CFD to characterize the opening and closing of check valves. Specifically, using CFD results, a procedure was developed to determine valve flow coefficients (CV) as a function of disk lift positions as well as to determine the flow rate required to achieve full open or predict intermediate disk lift positions. The method could be used for a wide range of check valves such as swing check valves, lift check valves, tilting disk check valves, or inline check valves. Using CFX which is a part of the ANSYS suite of finite element programs, examples of the predictive nature of CFD to characterize check valve performance are presented to address swing check and lift check valve designs. It is shown that balancing flow-induced forces on the disk and considering the disk assembly weight in the process is sufficient to model the valve lift behavior. Analysis results from this approach were compared with available test data of the modeled valves. The comparison showed good agreement, thus validating that both flow coefficients (CV) and flow rates across the valves at different disk lift positions can be reasonably predicted with this approach. The results of this study suggest that this approach can be used for valve design optimization and flow analysis of check valves. However, it should be pointed out that CFD is an evolving technology and is not a substitute for testing. The use of this tool compliments testing and, if carefully managed, can save valve development cost.
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Wilkowski, Gery, Do-Jun Shim, Bud Brust, and Suresh Kalyanam. "Reality Check on Girth Weld Defect Acceptance Criteria." In 2010 8th International Pipeline Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ipc2010-31629.
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This paper examines the inherent conservatisms of alternative girth weld defect acceptance criteria from the 2007 API 1104 Appendix A, CSA Z662 Appendix K, and the proposed EPRG Tier 2 criteria. The API and CSA codes have the same empirical limit-load criteria, where it has previously been shown that the conservatism on the failure stress is ∼30 to 50 percent compared to pipe test data prior to applying any safety factors. In terms of flaw length, it was found that the API/CSA limit-load equation might allow a flaw of 5% of the pipe circumference, where the properly validated limit-load equation would allow a flaw of 75% of the circumference, i.e., a safety factor of 30 percent on load corresponded to a safety factor of 15 on flaw length for that example case. Similarly there are conservatisms in a proposed EPRG Tier 2 girth weld defect acceptance criterion. This proposed criterion was directly based on curved-wide-plate data to assure that toughness was sufficient to meet limit-load conditions for a curved-wide plate. However, the curved-wide plates are really an intermediate-scale test, and still require proper scaling to pipes of different diameters. The proposed Tier 2 EPRG allowable flaw length is 7T from a large database of curved-wide-plate tests with the a/t value of less than 0.5 (or a < 3mm), and the failure stress being equal to the yield strength of the base metal (also requires the weld metal overmatch the base metal strength, and the Charpy energy at the defect location have a minimum > 30 J and average > 40 J). However, the widths of those curved-wide-plate tests are typically a factor 5 to 12 times less than typical large-diameter pipes. The proper limit-load/fracture mechanics scaling solution would have the flaw length proportioned to the plate width, not the specimen thickness. Additionally, the proper limit-load solution for a pipe in bending gives a much larger tolerable flaw size at the yield stress loading than a plate or pipe under pure tension. Example calculations showed that the EPRG Tier 2 approach is conservative on the flaw lengths by approximately 9 for pure axial tension loading, and between 34 to 79 for a pipe under bending. Suggestions are presented for an improved procedure that accounts for proper limit-load solutions for pipe tests, effects of pipe diameter, effects of internal pressure, and also a much simpler approach to incorporate the material toughness than the 2007 API 1104 Appendix A Option 2 FAD-curve approach. The fracture analyses could evoke SENB, SENT testing, or have relatively simple Charpy test data to assess the transition temperatures to ensure ductile initiation will occur.
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Willockx, Arnout, Christophe Tjoen, Hendrik-Jan Steeman, and Michel De Paepe. "Natural Convection Over Bodies in the Transition Zone Between Laminar Thin Boundary Layer Dominated and Conduction Dominated Natural Convection." In ASME 2005 Summer Heat Transfer Conference collocated with the ASME 2005 Pacific Rim Technical Conference and Exhibition on Integration and Packaging of MEMS, NEMS, and Electronic Systems. ASMEDC, 2005. http://dx.doi.org/10.1115/ht2005-72702.
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Different Rayleigh (Ra)-Nusselt (Nu)-correlations exist for natural convection from bodies. Different characteristic lengths are used by different authors. This paper reports of an experiment in which Ra is varied in an intermediate range. It is an interesting range because the values lie in a transition zone between laminar thin boundary layer dominated and conduction dominated natural convection. The experimental data is compared with existing correlations to check the accuracy and validity of these correlations for this transitional range of Ra. A new correlation that is only valid in this transitional zone is also proposed.
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Tonshal, Basavaraj, Yifan Chen, and Pietro Buttolo. "Determine Mesh Orientation by Voxel-Based Principal Component Analysis." In ASME 2006 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/detc2006-99380.
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In this paper we propose a new method to determine the part orientation of a 3D mesh based on Principal Component Analysis (PCA). Although the idea and practice of using PCA to determine part orientation is not new, it is not without practical issues. A major drawback of PCA, when it comes to dealing with meshes comprised of nodes and elements, is that the results are tessellation-dependent because of its sensitivity to variability. Two CAE meshes derived from the same CAD model but with different mesh node distribution characteristics, for instance, can yield different principal components. This is an undesirable outcome because the primary concern in model reorientation is shape, not the representational details of the shape. In order to reduce the influence of node characteristics, weight factors were proposed in the past, but the improvement is limited. To overcome this limitation, we must eliminate the influence of mesh node distribution. We achieve this by introducing an intermediate workspace, which is subsequently voxelized. We then find the intersection of the mesh model with the voxelized workspace. We collect the intersecting voxels to form an intermediate, tessellation-independent representation of the mesh. Applying PCA to this “neutralized” representation allows us to achieve mesh-property-independent results. The voxel representation also provides an opportunity of computational efficiency. We implemented an octree data structure to store the voxels and implemented a fast intersection (between a mesh element and a voxel) check procedure utilizing the interval overlap check derived from the separating axis theorem. Practical issues concerning determination of the voxel space resolution is addressed. A two-step trial and correction approach is proposed to enhance the consistency of results. Our voxel-based PCA is robust, fast, and straightforward to implement. Application examples are shown demonstrating the effectiveness and efficiency of this approach.
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Brunin, Olivier. "Management of PWR Steam Generator Tube Plugging and Primary Flow-Rate Predictions." In ASME 2011 Pressure Vessels and Piping Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/pvp2011-57357.
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The tubes of PWR steam generators are part of the second barrier between the nuclear fuel and the environment. The integrity in operation of the tubes is addressed with Non Destructive Examinations (NDE) and flaw allowances criteria. If a tube does not match the criteria, it is plugged. As a consequence, the steam generators tube plugging (SGTP) may increase during the maintenance outages. This increase has to be managed properly because it basically affects the heat exchange capacity of the Nuclear Steam Supply System (NSSS). This can be managed by performing long-term predictions in order to prepare in advance the possibility of steam generator replacements. But this “long-term operation” management is to be completed with an intermediate term management considering the real operating conditions of the NSSS. Intermediate term predictions, based on a simulation of the mechanisms leading to the degradation of the tubes, are annually compared with the evolution of real NDE and real SGTP. These predictions are completed with the set-up of a model, for each Reactor Coolant System (RCS), considering the relation between the average SGTP and the primary flow-rate. The predictions are used to check that the real operating conditions of each NSSS can be matched with an existing safety file.
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Engel, Robert. "Fretting-Wear Damage at Hydraulic Snubber Pins." In ASME 2005 Pressure Vessels and Piping Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/pvp2005-71222.
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During the refueling outage at the Leibstadt Nuclear Power Plant in August 2002 and 2003 some severely worn hydraulic snubber pins were found at a main steam line support inside the turbine building. Possible causes of the failure were considered to be increased loads due to the implementation of a snubber reduction program in the 1996 to 1998 time period, or flow-induced vibration from the extended power uprate implemented in four steps from 1998 to 2002. During the 2003 outage, a vibration measurement program as well as a root cause analysis were started to check the integrity of the whole system and to reduce or eliminate the degradation mechanism. The dynamic measurement data obtained during the 2003 power ascension showed that the vibration acceptance criteria were met. However, the main steam line support with the worn snubber pins experienced a horizontal relative movement between the pins and the clamps. This started at a power level corresponding to an intermediate power uprate step. Four different pragmatic local design solutions were considered to prevent the severe wear.
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Cazauran, Xavier, Yves Birembaut, Rolf Hahn, Hans Kockelmann, and Stephanie Moritz. "Gas Leakage Correlation." In ASME 2009 Pressure Vessels and Piping Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/pvp2009-77882.
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A project has been carried out on the correlation of leakage measurements of different gases in specific conditions in bolted flanged assembly. The objectives were: • to check if the relationship between the leakage measurements of Helium, CO2, refrigerant R134a and CH4 would be similar to results of calculations that can be found when using correlation formulas, • to compare emissions of a typical laboratory fluid (Helium) with process fluids like methane, used in petrochemical plants, as well as CO2 and R134a, used in the refrigeration industry. Referring to TA Luft and VDI 2440, which specify a unique test for the certification of gaskets, the configurations of the testing installation used consist of flanges assembled with either PTFE based, graphite or fibre based gaskets. Different gasket loads and internal pressure were applied in order to simulate molecular, intermediate or laminar leakage flow rates. This article describes the test configurations and shows the leakage measurement results. It also compares the ratios between the leakage values and the results that would be obtained by predicting the leakage of another gas and/or in other pressure conditions, using Poiseuille or Knudsen laws.
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Bunnik, Tim, and Rene´ Huijsmans. "Validation of Wave Propagation in Numerical Wave Tanks." In ASME 2005 24th International Conference on Offshore Mechanics and Arctic Engineering. ASMEDC, 2005. http://dx.doi.org/10.1115/omae2005-67221.
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During the last few years there has been a strong growth in the availability and capabilities of numerical wave tanks. In order to assess the accuracy of such methods, a validation study was carried out. The study focuses on two types of numerical wave tanks: 1. A numerical wave tank based a non-linear potential flow algorithm. 2. A numerical wave tank based on a Volume of Fluid algorithm. The first algorithm uses a structured grid with triangular elements and a surface tracking technique. The second algorithm uses a structured, Cartesian grid and a surface capturing technique. Validation material is available by means of waves measured at multiple locations in two different model test basins. The first method is capable of generating waves up to the break limit. Wave absorption is therefore modeled by means of a numerical beach and not by mean of the parabolic beach that is used in the model basin. The second method is capable of modeling wave breaking. Therefore, the parabolic beach in the model test basin can be modeled and has also been included. Energy dissipation therefore takes place according to physics which are more related to the situation in the model test basin. Three types of waves are generated in the model test basin and in the numerical wave tanks. All these waves are generated on basin scale. The following waves are considered: 1. A scaled 100-year North-Sea wave (Hs = 0.24 meters, Tp = 2.0 seconds) in deep water (5 meters). 2. A scaled operational wave (Hs = 0.086 meters, Tp = 1.69 seconds) at intermediate water depth (0.86 meters) generated by a flap-type wave generator. 3. A scaled operational wave (Hs = 0.046 meters, Tp = 1.2 seconds) in shallow water (0.35 meters) generated by a piston-type wave generator. The waves are generated by means of a flap or piston-type wave generator. The motions of the wave generator in the simulations (either rotational or translational) are identical to the motions in the model test basin. Furthermore, in the simulations with intermediate water depth, the non-flat contour of the basin bottom (ramp) is accurately modeled. A comparison is made between the measured and computed wave elevation at several locations in the basin. The comparison focuses on: 1. Reflection characteristics of the model test basin and the numerical wave tanks. 2. The accuracy in the prediction of steep waves. 3. Second order effects like set-down in intermediate and shallow water depth. Furthermore, a convergence study is presented to check the grid independence of the wave tank predictions.