Monitoring and vibration control of a fluid catalytic cracking unit

Wendell D. Varela,Ronaldo C. Battista,Igor Braz N. Gonzaga 국제구조공학회 2022 Smart Structures and Systems, An International Jou Vol.29 No.4

Oil refineries' Fluid Catalytic Cracking Units (FCCU) when in full operation may exhibit strong fluid dynamics caused by turbulent flow in the piping system that may induce vibrations in other mechanical and structural components of the Unity. This paper reports on the experimental-theoretical-computational program performed to get the vibration properties and the dynamic response amplitudes to find out alternative solutions to attenuate the excessive vibrations that were causing fatigue fractures in components of the bottle like reactor-regenerator of an FCC unit in operation in an existing oil refinery in Brazil. Solutions to the vibration problem were sought with the aid of a 3D finite element model calibrated with the results obtained from experimental measurements. A short description of the found solutions is given and their effectiveness are shown by means of numerical results. The solutions were guided by the concepts of structural stiffening and dynamic control performed by a nonlinear pendulum controller whose mechanical design was based on parameters determined by means of a parametric study carried out with 2D and 3D mathematical models of the coupled pendulum-structure system. The effectiveness of the proposed solutions is evaluated in terms of the fatigue life of critical welded connections.

Chemical Ecology: Decoding the Signals of Insects

wendell L. Roelofs 한국응용곤충학회 2005 한국응용곤충학회 학술대회논문집 Vol.2005 No.05

성사의 제정과 토착화의 한계

양리완(Wendell Langley),김수복(번역자) 광주가톨릭대학교 신학연구소 1972 神學展望 Vol.- No.17

두려움 가운데 떠오른 생각들

웬델 베리(Wendell Berry),김성호 (번역자) 제3시대그리스도교연구소 2002 시대와 민중신학 Vol.7 No.-

건강하지 않은 장애인

수잔 웬델(Susan Wendell),전혜은(번역자) 도서출판여이연 2012 여성이론 Vol.- No.27

[번역]품성의 형성: 빌립보서 4:8-9에 나타난 덕

벤델 윌리스,이준호[역] 한영신학대학교 2012 韓榮論叢 Vol.16 No.S

Terrain-Influenced Local Wind Forecasting for the Sasebo Typhoon Haven: Improved Empirical Techniques

Joel W. Feldmeier,Wendell A. Nuss,Russell L. Elsberry 한국기상학회 2014 Asia-Pacific Journal of Atmospheric Sciences Vol.50 No.4

Although the Sasebo, Japan harbor is usually a “typhoon haven” from tropical cyclone (TC) winds due to terrain-blocking effects, in rare cases damaging winds occur that may be attributed to terrain channeling. An empirical parametric model technique is developed and tested that includes consideration of the TC wind structure, land frictional effects, and terrain influences affecting the maximum wind speeds in the harbor when TCs pass within 200 nautical miles of Sasebo. The terrain influence is represented by two sets of wind direction-dependent acceleration factors. The first set, which is directly from the ratio of the local wind to the adjusted parametric wind for TCs passages during 2003-2010, provides mean values that represent the terrain blocking and channeling effects, but the variability with wind direction may be suspect. The second set derived from a large sample of reanalysis winds not limited to TCs has better variability properties, but is not easily related to just the TC passages. A new nomogram modified to include TC wind structure has higher estimates of Sasebo sustained winds for some TC tracks that may be related to terrain influences, but is limited due to the number of TC structure estimates in the developmental sample. These empirical models have the advantage of ease and low cost for future use in also estimating the combined uncertainty in the local winds in Sasebo harbor due to TCs.

A system of multiple controllers for attenuating the dynamic response of multimode floor structures to human walking

Ronaldo C. Battista,Wendell D. Varela 국제구조공학회 2019 Smart Structures and Systems, An International Jou Vol.23 No.5

Composite floor structures formed by continuous slab panels may be susceptible to excessive vibrations, even when properly designed in terms of ultimate limit state criteria. This is due to the inherent vibration characteristics of continuous floor slabs composed by precast orthotropic reinforced concrete panels supported by steel beams. These floor structures display close spaced multimode vibration frequencies and this dynamic characteristic results in a non-trivial vibration problem. Structural stiffening and/or insertion of struts between floors are the usual tentative solution applied to existing vibrating floor structures. Such structural alterations are in general expensive and unsuitable. In this paper, this vibration problem is analyzed on the basis of results obtained from experimental measurements in typical composite floors and their theoretical counterpart obtained with computational modeling simulations. A passive control system composed by multiple synchronized dynamic attenuators (MSDA) was designed and installed in these floor structures and its efficiency was evaluated both experimentally and through numerical simulations. The results obtained from experimental tests of the continuous slab panels under human walking dynamic action proved the effectiveness of this control system in reducing vibrations amplitudes.

Review : Personalized management of cirrhosis by non-invasive tests of liver fibrosis

( Grace Lai-hung Wong ),( Wendell Zaragoza Espinosa ),( Vincent Wai-sun Wong ) 대한간학회 2015 Clinical and Molecular Hepatology(대한간학회지) Vol.21 No.3

Owing to the high prevalence of various chronic liver diseases, cirrhosis is one of the leading causes of morbidity and mortality worldwide. In recent years, the development of non-invasive tests of fibrosis allows accurate diagnosis of cirrhosis and reduces the need for liver biopsy. In this review, we discuss the application of these non-invasive tests beyond the diagnosis of cirrhosis. In particular, their role in the selection of patients for hepatocellular carcinoma surveillance and varices screening is highlighted. (Clin Mol Hepatol 2015;21:200-211)

Reidentification of pheromone composition of Sparganothis sulfureana (Clemens) and evidence of geographic variation in male responses from two US states

Junwei Zhu,Kye-Chung Park,Carolyn Garvey,Daniel Mahr,Satoshi Nojima,Wendell Roelofs,Tom Baker,Sridhar Polavarapu 한국응용곤충학회 2009 Journal of Asia-Pacific Entomology Vol.12 No.4

GC-EAD analyses of pheromone gland extracts of calling female Sparganothis sulfureana revealed at least 6 compounds that consistently elicited antennal responses from male antennae. In addition to the major pheromone compound, (E)-11-tetradecenyl acetate (E11–14:OAc), which was previously reported, the other compounds were found to be (E)-9-dodecenyl acetate (E9–12:OAc), (Z)-9-dodecenyl acetate (Z9–12:OAc), (Z)-9-tetradecenyl acetate (Z9–14:OAc), (Z)-11-tetradecenyl acetate (Z11–14:OAc), and (E)-11-tetradecenol (E11–14:OH). Tetradecyl acetate, hexadecyl acetate and hexadecenyl acetates were also present in the extracts, but elicited no EAG response frommale antennae. Wind tunnel tests demonstrated that males from NewJersey responded equally well to a blend containing five pheromone components in relative to the pheromone glands of calling females. Different male-response profiles from field-trapping tests conducted in the states of Wisconsin and NewJersey were observed, respectively. Significantly higher numbers of male S. sulfureana were caught in New Jersey in traps baited with the binary blend of E11–14:OAc (30 μg) with 1% of Z11–14:OAc, but males from Wisconsin responded equally well to traps containing blends of E11–14:OAc with 0–10% of Z11–14: OAc. The addition of more than 10% of Z11–14:OAc to the primary pheromone compound reduced male captures significantly in both states. Male catches were doubled by adding E9–12:OAc and E11–14:OH to the most attractive binary blend in both states. The trapping test with caged live virgin female moths showed that males in Wisconsin preferred females from the local population than those from NewJersey. The differences in male responses observed may indicate the existence of pheromone polymorphism in this species. GC-EAD analyses of pheromone gland extracts of calling female Sparganothis sulfureana revealed at least 6 compounds that consistently elicited antennal responses from male antennae. In addition to the major pheromone compound, (E)-11-tetradecenyl acetate (E11–14:OAc), which was previously reported, the other compounds were found to be (E)-9-dodecenyl acetate (E9–12:OAc), (Z)-9-dodecenyl acetate (Z9–12:OAc), (Z)-9-tetradecenyl acetate (Z9–14:OAc), (Z)-11-tetradecenyl acetate (Z11–14:OAc), and (E)-11-tetradecenol (E11–14:OH). Tetradecyl acetate, hexadecyl acetate and hexadecenyl acetates were also present in the extracts, but elicited no EAG response frommale antennae. Wind tunnel tests demonstrated that males from NewJersey responded equally well to a blend containing five pheromone components in relative to the pheromone glands of calling females. Different male-response profiles from field-trapping tests conducted in the states of Wisconsin and NewJersey were observed, respectively. Significantly higher numbers of male S. sulfureana were caught in New Jersey in traps baited with the binary blend of E11–14:OAc (30 μg) with 1% of Z11–14:OAc, but males from Wisconsin responded equally well to traps containing blends of E11–14:OAc with 0–10% of Z11–14: OAc. The addition of more than 10% of Z11–14:OAc to the primary pheromone compound reduced male captures significantly in both states. Male catches were doubled by adding E9–12:OAc and E11–14:OH to the most attractive binary blend in both states. The trapping test with caged live virgin female moths showed that males in Wisconsin preferred females from the local population than those from NewJersey. The differences in male responses observed may indicate the existence of pheromone polymorphism in this species.