Bibliografías temáticas / Diaphragm

Literatura académica sobre el tema "Diaphragm"

Autor: Grafiati
Publicado: 4 de junio de 2021
Última modificación: 29 de julio de 2024

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Artículos de revistas sobre el tema "Diaphragm"

1

Yang, Mu Ye, Rong Liu, Bo Hai Ji, Han Jiang Xu, Ce Chen y Duan Duan Zhao. "Fatigue Stress Analysis of Diaphragm Cap Hole in Orthotropic Steel Bridge Decks". Applied Mechanics and Materials 204-208 (octubre de 2012): 3265–69. http://dx.doi.org/10.4028/www.scientific.net/amm.204-208.3265.

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Influence of diaphragm parameter on stress amplitude and fatigue damage of diaphragm details were investigated based on Tai Zhou Yangtze River Bridge. FEM of steel bridge deck and diaphragm detail were established. Boundary conditions of the diaphragm details FEM were interpolated by sub-model method, and the accurate local stresses of diaphragm details correspond to different lateral distribution of wheels were calculated. Results show the stress amplitude of diaphragm details reach maximum when wheel off-center position is 150mm, and it decreases with the increase of wheel off-center position greatly. The stress amplitude of diaphragm details increase with the increase of the distance of diaphragms, and increasing diaphragm’s thickness can improve fatigue stress of steel bridge deck.
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2

Roopa, R., P. Navin Karanth y S. M. Kulkarni. "Design, fabrication and experimental studies of compliant flexure diaphragm for micro pump". International Journal of Engineering & Technology 7, n.º 2.21 (20 de abril de 2018): 66. http://dx.doi.org/10.14419/ijet.v7i2.21.11838.

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This study reports the performance of piezo actuated compliant flexure diaphragm for micropump and MEMS application. To achieve the high performance of diaphragm at the low operating voltage compliant flexure diaphragm design is introduced. Very limited work has done on the diaphragms of micropump. Large numbers of mechanical micropumps have used plane diaphragms. The central deflection of diaphragm plays an important role in defining the micropump performance. The flow rate of mechanical type micropump strongly depends on the central deflection of diaphragm. In this paper compliant flexure diaphragms are designed for micropump to achieve higher deflection at lower operating voltage. Finite element analysis of compliant flexure diaphragm with single layer PVDF (Polyvinylidene fluoride) actuator is simulated in COMSOL. Compliant flexure diaphragms with a different number of flexures are analyzed. The central deflection of compliant flexure diaphragms is measured for driving voltages of 90V to 140V in 10 steps. The deflection of the compliant flexure diaphragm mainly depends on flexure width and length, the number of flexures in the diaphragm, PVDF thickness, diaphragm thickness and driving voltage. Use of compliant flexure diaphragm for micropump will reduce the mass and driving voltage of micropump. An attempt is made to compare the results of compliant flexure diaphragms with plane diaphragms. From the experimental results it is noticed that the compliant flexure diaphragm deflection is twice that of the plane diaphragm at same driving voltage. Deflection of three flexure and four flexure compliant diaphragms is 10.5µm and 11.5µm respectively at 140V.
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3

Solovev, M., A. Leonhardt, A. Graf, A. Kunke y V. Kräusel. "Development of geometry variants and forming technology for metal diaphragms to increase the efficiency of diaphragm compressor". IOP Conference Series: Materials Science and Engineering 1284, n.º 1 (1 de junio de 2023): 012009. http://dx.doi.org/10.1088/1757-899x/1284/1/012009.

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Abstract This article outlines the development of an elastically foldable, bistable diaphragm geometry that enables an increase in the compression volume of diaphragm compressors compared to the use of flat diaphragms. Using a Finite Element Model (FEM) in ABAQUS/Standard, several membrane geometries (truncated cone, cone, and dome) were calculated and analyzed with regard to their elastic deformation. Selected geometries were produced using Single Point Incremental Forming (SPIF) and tested by applying full-area pneumatic pressure to determine the diaphragm’s lifetime.
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4

Li, Jiyang, Lin Liang, Xiaohan Jia y Xueyuan Peng. "A new generatrix of the cavity profile of a diaphragm compressor". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 228, n.º 10 (7 de noviembre de 2013): 1754–66. http://dx.doi.org/10.1177/0954406213511077.

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The small flowrate and the diaphragm’s short life are two shortcomings of the diaphragm compressor. This paper presents a new generatrix of the cavity profile of a diaphragm compressor to increase cavity volume and decrease diaphragm's radial stress. To verify the design theory, the radial stresses on the oil side of the diaphragm in the cavities with the new and traditional generatrices were tested, and the experimental radial stresses agreed with the theoretical values. As the most important evaluation criteria of the cavity profile, the volumes of the cavities with different generatrices and the radial stress distribution of the diaphragm within were investigated under various design conditions. The results showed that the volume of the cavity with the new generatrix was about 6.5% larger than that with the traditional generatrix under the same design condition. Otherwise, with the same cavity volume and radius, the maximal radial stress of the diaphragm in the cavity with the new generatrix decreased by 10.3% stably, compared to that in the cavity with a traditional generatrix. Likewise, in the diaphragm’s centric region where the additional stress caused by the discharge holes occurred, the maximal radial stress of the diaphragm in the cavity with the new generatrix decreased about 11.5%.
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5

Fleischman, Robert B., Kenneth T. Farrow y Kristin Eastman. "Seismic Performance of Perimeter Lateral-System Structures with Highly Flexible Diaphragms". Earthquake Spectra 18, n.º 2 (mayo de 2002): 251–86. http://dx.doi.org/10.1193/1.1490547.

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Building structures are typically designed using the assumption that the floor systems serve as a rigid diaphragm between the vertical elements of the lateral force-resisting system (lateral system). However, perimeter lateral-system structures with long floor spans possess diaphragms that behave quite flexibly. Difficulty can exist in predicting diaphragm force demand in these structures. Thus, current design may provide insufficient strength to maintain elastic diaphragm response. Inelastic diaphragm response exacerbates the effects of diaphragm flexibility. Such response may lead to poor seismic performance, including nonductile diaphragm failure or structural instability due to high drift demands in the gravity system. An analytical study was performed to determine the effect of diaphragm flexibility and strength on the seismic performance of perimeter lateral-system structures with highly flexible diaphragms. Nonlinear transient analyses were performed using ground motions suites corresponding to multiple levels of hazard for high seismic zones. Design recommendations for flexible diaphragms are presented.
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6

Okubo, Yuhei, Hiro Ota, Kazuki Syoji y Satomitsu Imai. "A Prototype MEMS Actuator Driven by Magnetic Fluid Enclosed with Polyimide Diaphragms". Key Engineering Materials 523-524 (noviembre de 2012): 557–62. http://dx.doi.org/10.4028/www.scientific.net/kem.523-524.557.

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A MEMS actuator using a magnetic fluid enclosed with polyimide (PI) diaphragms is proposed. The actuator produces a large displacement and force thanks to its structure in which a magnetic fluid is confined between two thin-film PI diaphragms (diameter: 5 mm) fabricated on two silicon substrates. The two substrates with diaphragms are glued together by sandwiching a polyester sheet to form a diaphragm unit. The thickness of the diaphragms is 8.5 µm so that they can deflect greatly. The magnetic fluid inserted between the two diaphragms is composed of magnetite and isoparaffin. The diaphragm unit (containing the magnetic fluid) is deflected by applying an external magnetic field to it with a magnet coil. Response times and displacements of the diaphragms were measured when a magnetic field was applied. Under an applied voltage of 10 V, the diaphragm unit could produce displacements of 4 µm at the diaphragm center. Response time to reach 90% of the maximum diaphragm displacement was about 2 s. Under an applied voltage of 80 V, force generated by the diaphragm unit was 0.065N. It is concluded from these experimental results that the proposed actuator is applicable to MEMS devices such as micro pumps and give another example here.
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7

Nguyen, Taitan, Neal A. Rubinstein, Camasamudram Vijayasarathy, Lawrence C. Rome, Larry R. Kaiser, Joseph B. Shrager y Sanford Levine. "Effect of chronic obstructive pulmonary disease on calcium pump ATPase expression in human diaphragm". Journal of Applied Physiology 98, n.º 6 (junio de 2005): 2004–10. http://dx.doi.org/10.1152/japplphysiol.00767.2004.

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We have previously demonstrated that human diaphragm remodeling elicited by severe chronic obstructive pulmonary disease (COPD) is characterized by a fast-to-slow myosin heavy chain isoform transformation. To test the hypothesis that COPD-induced diaphragm remodeling also elicits a fast-to-slow isoform shift in the sarcoendoplasmic reticulum Ca2+ ATPase (SERCA), the other major ATPase in skeletal muscle, we obtained intraoperative biopsies of the costal diaphragm from 10 severe COPD patients and 10 control subjects. We then used isoform-specific monoclonal antibodies to characterize diaphragm fibers with respect to the expression of SERCA isoforms. Compared with control diaphragms, COPD diaphragms exhibited a 63% decrease in fibers expressing only fast SERCA (i.e., SERCA1; P < 0.001), a 190% increase in fibers containing both fast and slow SERCA isoforms ( P < 0.01), and a 19% increase ( P < 0.05) in fibers expressing only the slow SERCA isoform (i.e., SERCA2). Additionally, immunoblot experiments carried out on diaphragm homogenates indicated that COPD diaphragms expressed only one-third the SERCA1 content noted in control diaphragms; in contrast, COPD and control diaphragms did not differ with respect to SERCA2 content. The combination of these histological and immunoblot results is consistent with the hypothesis that diaphragm remodeling elicited by severe COPD is characterized by a fast-to-slow SERCA isoform transformation. Moreover, the combination of these SERCA data and our previously reported myosin heavy chain isoform data (Levine S, Nguyen T, Kaiser LR, Rubinstein NA, Maislin G, Gregory C, Rome LC, Dudley GA, Sieck GC, and Shrager JB. Am J Respir Crit Care Med 168: 706–713, 2003) suggests that diaphragm remodeling elicited by severe COPD should decrease ATP utilization by the diaphragm.
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8

Kim, Yong Hwy, Ji Hoon Phi, Seung-Ki Kim y Kyu-Chang Wang. "Growth pattern of craniopharyngioma determined by the origin of tumor regarding diaphragma sellae and the competency of the aperture: Reappraisal in the era of endoscopic endonasal surgery". Journal of Korean Skull base society 18, n.º 1 (31 de mayo de 2023): 24–35. http://dx.doi.org/10.55911/jksbs.23.0005.

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Background: Advances in the endoscopic endonasal approach (EEA) have increased the under-standing of craniopharyngioma anatomy. We have previously proposed a relationship among cranio-pharyngioma growth pattern, their origin relative to the diaphragm sellae, and their aperture compe-tency. To reappraise that relationship, we retrospectively reviewed the diaphragm sellae anatomy of patients who underwent EEA for craniopharyngioma. Materials and Methods: From May 2010 to January 2013, thirty five patients underwent EEA procedures for craniopharyngiomas. Twenty patients without a surgical history were included in the study, and medical records describing the spatial relations between the tumors and the diaphragma sellae were reviewed and correlated with the tumor growth patterns on preoperative images. Results: All of the tumors were completely removed. Three prechiasmatic tumors were located un-der intact diaphragma sellae. Six retrochiasmatic tumors were composed of supra- and subdiaphrag-matic components that were continuous through an incomplete aperture of the diaphragm. Eleven retrochiasmatic tumors were located above intact diaphragms. Visual symptoms were normalized or improved in twelve of the sixteen patients with preoperative visual deficits. Preoperative hypotha-lamic dysfunction was recovered in ten of twelve patients. Conclusions: The EEA revealed the detailed tumor anatomy and confirmed our previous hypoth-esis that craniopharyngioma growth patterns are principally determined by the origin of the tumor relative to the diaphragma sellae and by the aperture competency. The EEA is indicated for removing both prechiasmatic and retrochiasmatic craniopharyngiomas.
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9

Farkas, G. A. y D. F. Rochester. "Functional characteristics of canine costal and crural diaphragm". Journal of Applied Physiology 65, n.º 5 (1 de noviembre de 1988): 2253–60. http://dx.doi.org/10.1152/jappl.1988.65.5.2253.

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We estimated the in situ force-generating capacity of the costal and crural portions of the canine diaphragm by relating in vitro contractile properties and diaphragmatic dimensions to in situ lengths. Piezoelectric crystals were implanted on right costal and left crural diaphragms of anesthetized dogs, via midline laparatomy. With the abdomen reclosed, diaphragm lengths were recorded at five lung volumes. Contractile properties of excised muscle bundles were then measured. In vitro force-frequency and length-tension characteristics of the costal and crural diaphragms were virtually identical; their optimal force values were 2.15 and 2.22 kg/cm2, respectively. In situ, at residual volume, functional residual capacity (FRC), and total lung capacity the costal diaphragm lay at 102, 95, and 60% of optimal length (Lo), whereas the crural diaphragm lay at 88, 84, and 66% of Lo. Muscle cross-sectional area was 40% greater in costal than in crural diaphragms. Considering in situ lengths, cross-sectional areas, and in vitro length-tension characteristics at FRC, the costal diaphragm could exert 60% more force than the crural diaphragm.
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10

Filiatrault, Andre, David Fischer, Bryan Folz y Chia-Ming Uang. "Experimental parametric study on the in-plane stiffness of wood diaphragms". Canadian Journal of Civil Engineering 29, n.º 4 (1 de agosto de 2002): 554–66. http://dx.doi.org/10.1139/l02-036.

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This paper presents the results of in situ quasi-static tests on a full-scale wood floor diaphragm in a two-storey woodframe house. The main objective of the study was to investigate the in-plane flexibility/rigidity of the diaphragm. Fourteen different diaphragm and structural configurations were investigated. The main parameters considered in the study included the nail schedule, panel-edge blocking, sub-floor adhesive, perpendicular walls above and below the diaphragm, and wall finish materials. The results indicated that panel-edge blocking increased significantly the diaphragm shear stiffness, particularly for diaphragms without sub-floor adhesive. Also, the presence of perpendicular walls acting as additional chord members caused a significant increase in the flexural stiffness of the diaphragm. The design procedure included in the Uniform Building Code (UBC) to compute in-plane diaphragm deformations was assessed by comparing its predictions with the experimental results. The UBC predictions agreed well with the experimental results for some configurations, but the correlation was poor for others.Key words: diaphragms, floor, tests, wood, wooden structures.
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Tesis sobre el tema "Diaphragm"

1

Orrey, Samantha Taylor. "The relationship between diaphragm thickness, diaphragm strength and diaphragm endurance in young, healthy individuals". Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86666.

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Thesis (MScPhysio)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Introduction: In the intensive care unit population, approximately 40% of patients require mechanical ventilation and 20-25% of these patients will encounter difficulties in the discontinuation of mechanical ventilation. As mechanical ventilation affects the diaphragm, a better understanding of the structural and functional changes of the diaphragm is warranted. Method: A scoping review was done to determine whether a relationship between diaphragm thickness, diaphragm strength and diaphragm endurance had been established. Seven databases were searched using a specific search strategy. Papers were identified based on pre-defined inclusion criteria. Data was extracted by the primary investigator (PI) into a self-developed excel spreadsheet. Criteria were developed for a more focused review to inform the planning of a primary study. The primary study investigated the relationship between diaphragm thickness, diaphragm strength and diaphragm endurance in young, healthy individuals. A sample of convenience was used; included healthy individuals (18-24); three activity-levels (sedentary; endurance- and strength related sporting activities); stratified for gender and BMI. Measurements included: Sonographic measurement of diaphragm thickness; mouth pressure manometer measurements for diaphragmatic strength; and fatigue resistance index as a measure of endurance. Participants were instructed to breathe through a pressure threshold device at 60% of PImax until task failure. The fatigue resistance index was calculated as PImax final/PImax initial. Intra-rater reliability was established and testing procedures standardised a priori. Results: 405 full texts were retrieved and assessed for inclusion into the review. Papers identified the evaluation of diaphragm function in a variety of populations. 23 papers were included in the focused review. Six papers were published on diaphragm thickness, six on diaphragm strength and eleven on diaphragm endurance. No papers identified the correlation between diaphragm thickness, diaphragm strength and diaphragm endurance. 55 subjects, males and females, were recruited for the primary study. Groups were similar at baseline with regards to gender, age and BMI. The mean age of the sample was 21.16 years (SD = 1.55), with a mean body mass index (BMI) of 25.43 kg/m2 (SD = 3.70). A moderate positive correlation was established between diaphragm thickness and diaphragm strength measurements (r = 0.52; r2 = 0.27; p < 0.01). Diaphragm thickness was not correlated with diaphragm endurance (r = -0.15; r2 = 0.02; p = 0.29). No relationship was found between the strength of the diaphragm and the endurance of the diaphragm (r= -0.19; r2 = 0.04; p= 0.16). Conclusion: Guidelines for the measurement of diaphragm function do exist, but they are not adhered to by the majority of studies. Study procedures are inconsistently reported and this may affect the reproducibility of techniques in future studies. We further conclude that a correlation exists between diaphragm thickness and diaphragm strength. The use of ultrasound to measure diaphragm thickness proved to be a reliable technology and gave a moderate indication of the strength of the diaphragm. This technology may help clinicians to detect and monitor dysfunction of the diaphragm in the early stages of admission to the acute setting.
AFRIKAANSE OPSOMMING: Inleiding: Ongeveer 40% van pasiente wat in intensiewe sorgeenheid behandel word, benodig intubasie en meganiese ventilasie. Tot 25% van hierdie pasiënte sal probleme ondervind in die staking van meganiese ventilasie. Meganiese ventilasie beïnvloed die diafragma, daarom word n beter begrip van die strukturele en funksionele veranderinge van die diafragma benodig. Metode: 'n Literatuur oorsig is gedoen om te bepaal of daar 'n verhouding bestaan tussen die dikte, krag en uithouvermoë van die diafragma. Sewe databasisse is deurgesoek aan die hand van spesifieke databasis gedefinieerde soektog strategie. Relevante artikels is geïdentifiseer aan die hand van pre-gedefinieerde insluiting kriteria. Data is onttrek en in ‘n self-ontwikkelde datablad opgesom deur die primêre ondersoeker (PI). Hierdie inligting is gebruik in die beplanning van ‘n primêre studie. Die doel van die primêre studie was om die verhouding tussen die diafragma dikte, krag en uithouvermoë in jong, gesonde individue te ondersoek. ‘n Gerieflikheids steekproef is gebruik; insluitend gesonde individue (18-24); drie aktiwiteits vlakke (passief; uithouvermoë- en krag verwante sportaktiwiteite) en breë spektrum vir geslag en ligaamsbou (BMI). Metings ingesluit: sonografiese meting van die diafragma se dikte; monddruk manometer metings vir diafragmatiese krag en ‘n moegheid/weerstand indeks as maatstaf van diafragmatiese uithouvermoë. Deelnemers is opdrag gegee om asem te haal deur toestel met druk maksimum gestel 60% van PImax, tot mislukking. Die moegheid/weerstand indeks is bereken as PImax finale / PImax oorspronlik. Intra-meter betroubaarheid is bepaal en toets prosedures is gestandaardiseer voordat data ingesamel is. Resultate: 405 vol teks artikels is uitgelig vir insluiting in die literatuur oorsig. Diafragmatiese funksie is ge-evalueer in 'n verskeidenheid bevolkings. Drie en twintig artikels is in die finale oorsig ingesluit. Ses artikels wat diafragma dikte evalueer, ses wat diafragmatiese krag evalueer en elf wat die diafragma se uithouvermoë evalueer is ingesluit in die oorsig. Geen van die artikels uitgelig het ‘n ooreenkoms tussen diafragma dikte, diafragma krag en diafragma uithouvermoë geïdentifiseer nie. 55 deelnemers is gewerf vir die primêre studie. Groepe was soortgelyk by basislyn met betrekking tot geslag, ouderdom en BMI. Die gemiddelde ouderdom van die toetsgroep was 21.16 jaar (SD=1.55), met 'n gemiddelde BMI van 25.43 kg/m2 (SD = 3.70). ‘n Middelmatige positiewe verhouding is waargeneem tussen diafragma dikte en krag (r = 0.52; r2 = 0.27; p < 0.01). Geen verhouding is gevind tussen diafragma dikte en uithouvermoë nie (r= -0.15; r2 = 0.02; p = 0.29). Daar is ook geen verhouding waargeneem tussen diafragma krag en diafragma uithouvermoë nie. (r= 0.19; r2 = 0.04; p = 0.16). Gevolgtrekking: Daar bestaan wel riglyne vir die meting van die diafragma se funksie, maar in die meerderheid van studies word dit nie nagekom nie. Studie prosedures is nie konsekwent weergegee nie en dit kan die resultate van tegnieke beinvloed in toekomende studies. ‘n Matige sterk verhouding is waargeneem tussen diafragmatiese dikte en krag. Die gebruik van ultraklank om die diafragma se dikte te meet is betroubare tegnologie en kan n redelike aanduiding gee oor die krag van die diafragma. Hierdie tegnologie kan praktisyne help om enige disfunksie van die diafragma te identifiseer en te monitor in die vroeë stadiums van toelating tot die akute omgewing.
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2

Singh, Bhajan. "The function of the human diaphragm as a volume pump and measurement of its efficiency /". Connect to this title, 2003. http://theses.library.uwa.edu.au/adt-WU2004.0029.

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O'Brien, Patrick Emmet. "Characterizing the Load-Deformation Behavior of Steel Deck Diaphragms using Past Test Data". Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/78679.

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Recent research has identified that current code level seismic demands used for diaphragm design are considerably lower than demands in real structures during a seismic event. However, historical data has shown that steel deck diaphragms, common to steel framed buildings, perform exceptionally well during earthquake events. A new alternative diaphragm design procedure in ASCE 7-16 increases diaphragm seismic demand to better represent expected demands. The resulting elastic design forces from this method are reduced by a diaphragm design force reduction factor, Rs, to account for the ductility of the diaphragm system. Currently, there exist no provisions for Rs factors for steel deck diaphragms. This research was therefore initiated to understand inelastic steel deck diaphragm behavior and calculate Rs factors. A review of the literature showed that a large number of experimental programs have been performed to obtain the in-plane load-deformation behavior of steel deck diaphragms. To unify review of these diaphragm tests and their relevant results, a database of over 750 tested specimens was created. A subset of 108 specimens with post-peak, inelastic behavior was identified for the characterization of diaphragm behavior and ductility. A new recommended method for predicting shear strength and stiffness for steel deck diaphragms with structural concrete fill is proposed along with an appropriate resistance factor. Diaphragm system level ductility and overstrength are estimated based on subassemblage test results and Rs factors are then calculated based on these parameters. The effects of certain variables such as deck thickness and fastener spacing on diaphragm ductility are explored.
Master of Science
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4

Bott, James Wescott. "Horizontal Stiffness of Wood Diaphragms". Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/32641.

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An experimental investigation was conducted to study the stiffness of wood diaphragms. Currently there is no method to calculate wood diaphragm stiffness that can reliably account for all of the various framing configurations. Diaphragm stiffness is important in the design of wood framed structures to calculate the predicted deflection and thereby determine if a diaphragm may be classified as rigid or flexible. This classification controls the method by which load is transferred from the diaphragm to the supporting structure below. Multiple nondestructive experimental tests were performed on six full-scale wood diaphragms of varying sizes, aspect ratios, and load-orientations. Each test of each specimen involved a different combination of construction parameters. The construction parameters investigated were blocking, foam adhesive, presence of designated chord members, corner and center sheathing openings, and presence of walls on top of the diaphragm. The experimental results are analyzed and compared in terms of equivalent viscous damping, global stiffness, shear stiffness, and flexural stiffness in order to evaluate the characteristics of each construction parameter and combinations thereof. Recommendations are presented at the end of this study as to the next steps toward development of an empirical method for calculating wood diaphragm stiffness.
Master of Science
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5

Zhu, Ercheng. "Exercise-induced diaphragm sarcolemmal injury". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0013/NQ52201.pdf.

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Singh, Bhajan. "The function of the human diaphragm as a volume pump and measurement of its efficiency". University of Western Australia. School of Biomedical and Chemical Sciences, 2004. http://theses.library.uwa.edu.au/adt-WU2004.0029.

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[Truncated abstract] The function of the diaphragm as a volume pump has not been adequately evaluated because there are no accurate methods to measure the volume displaced by diaphragm motion (ΔVdi). As a consequence, the work done, power output and efficiency of the diaphragm have not been measured. Efficiency of the diaphragm could be measured by relating the power output of the diaphragm to its neural activation. The aims of this thesis were to (a) develop a new biplanar radiographic method to measure ΔVdi and use this to evaluate the effect of costophrenic fibrosis and emphysema on ΔVdi, (b) develop a new fluoroscopic method to enable breath-by-breath measurements of ΔVdi, (c) evaluate a method for quantifying neural activation of the diaphragm, and (d) combine measurements of transdiaphragmatic pressure, ΔVdi, inspiratory duration and neural activation of the diaphragm to quantify the neuromechanical efficiency of the diaphragm
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Leong, Hong Sai. "Prediction of deformation of diaphragm wall". Thesis, University of Macau, 2001. http://umaclib3.umac.mo/record=b1445039.

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Radell, Peter J. "Studies of diaphragm fatigue and dysfunction /". Stockholm, 2001. http://diss.kib.ki.se/2001/91-628-4751-1/.

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Huang, Xinlei. "Diaphragm stiffness in wood-frame construction". Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/43908.

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This thesis presents an investigation of the in-plane stiffness of wood-frame diaphragms. Studying the stiffness of the diaphragm is important since it affects the distribution of lateral loads to shear walls. In order to determine the force in each shear wall, it is common to classify a diaphragm as either flexible in engineering design. Wood-frame diaphragms have generally been treated as flexible, which distributes the lateral loads using the straightforward “tributary area” approach. The accuracy of this assumption is investigated in this study. A detailed numerical model is developed for the study of the in-plane behaviour of wood-frame diaphragms. The model is validated with full-scale diaphragm tests, which has not been done so far for other diaphragm models in previous studies. As such, the model can be used as a “virtual laboratory” to predict the in-plane behaviour of wood-frame diaphragms with various configurations. A simplified model is developed based on the detailed diaphragm model to be used in the building analysis. The simplified model consists of “truss units”, which can be calibrated using analytical methods. In previous studies, wood-frame diaphragms were generally simplified as beam or spring models, where individual calibration is required for diaphragms with various configurations. Compared with these models, the simplified model developed here is obtained as an assembly of truss units, thus the number of calibration times can be considerably reduced. A case study of a one-storey wood-frame building is conducted to investigate the distribution of lateral loads to shear walls under different diaphragm flexibility conditions. It is found that the wood-frame diaphragm in this work is rather rigid, but is found that the distribution of lateral loads to the shear walls is strongly dependent on the relative stiffness of the diaphragm and the shear walls.
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Sheffy, Jacob. "Recording of diaphragm activity during anaesthesia". Thesis, Oxford Brookes University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261673.

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Libros sobre el tema "Diaphragm"

1

White Sands Test Facility (N.M.), ed. APU diaphragm testing: Test plan. Las Cruces, N.M: Lyndon B. Johnson Space Center, White Sands Test Facility, 1993.

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2

Bernward, Ulrich, ed. Chirurgie des Zwerchfells. Stuttgart: Enke, 1986.

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3

Phipps, M. E. The design of concrete blockwork diaphragm walls. Leicester: Aggregate Concrete Block Association, 1986.

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Koch, Wijnand F. R. M. y Enrico Marani. Early Development of the Human Pelvic Diaphragm. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-68007-9.

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Montague, T. I. Concrete blockwork diaphragm walls - prestressed and unprestressed. Manchester: UMIST, 1988.

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Gokoglu, Kamil Murst. End failures in stressed skin diaphragm action. Salford: University of Salford, 1985.

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H, Wendt y Commission of the European Communities. Directorate-General for Science, Research and Development., eds. Nickel-net supported cermet diaphragms and distance-free electrode-diaphragm sandwiches for advanced alkaline water electrolysis. Luxembourg: Commission of the European Communities, 1985.

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Phipps, M. E. The design of prestressed concrete blockwork diaphragm walls. Leicester: Aggregate Concrete Block Association, 1986.

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A, Harf, Gay R y Sastinne H, eds. Fonction Diaphragmatique, travail respiratoire: Réunion de printemps, Limoges, 21-23 mai 1987. Paris: Expansion scientifique française, 1987.

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Carswell, I. G. Long term performance of an anchored diaphragm wall embedded in stiff clay. Crowthorne, Berks: Transport and Road Reseach Laboratory, Structures Group, Ground Engineering Division, 1991.

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Capítulos de libros sobre el tema "Diaphragm"

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Liu, Xiao-Ming, Zhilong Liu, Yang Yu y Shunzeng Wang. "Mechanical Behavior and Failure Analysis of Diaphragm in Diaphragm Compressor for Hydrogen Refueling Station". En Proceedings of the 10th Hydrogen Technology Convention, Volume 1, 35–43. Singapore: Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-99-8631-6_4.

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AbstractDiaphragm compressor is widely used to pressurize hydrogen and is one of the key equipment in hydrogen refueling station. And the Diaphragm is one of the wearing parts of diaphragm compressor. The failure of the diaphragm makes the maintenance cost of diaphragm compressor high. Because of the large deflection of the diaphragm in the diaphragm compressor, its mechanical behavior has strong nonlinear characteristics, especially after considering the constraints on the diaphragm by the cavity of the cylinder head, it is difficult to accurately calculate with the analytical method. Therefore, considering the constraint condition of the cylinder, the finite element model of the diaphragm working in the diaphragm compressor is established. By the calculations of the diaphragm deformation and stress, the fractures of the hydrogen side of the diaphragm in the fault cases are analyzed. The results of static structure analysis and dynamic analysis are compared with diaphragm fault cases respectively, which shows the necessity of dynamic analysis in the failure analysis of diaphragm. Besides, the mechanical behavior of the diaphragm’s deformation indicates that the inertial effect of the diaphragm and collision between the diaphragm and the cavity cannot be ignored.
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Skandalakis, Lee J. y John E. Skandalakis. "Diaphragm". En Surgical Anatomy and Technique, 217–51. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-8563-6_5.

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Leichtle, Stefan W. y Michel B. Aboutanos. "Diaphragm". En Thoracic Surgery for the Acute Care Surgeon, 253–60. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-48493-4_18.

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Myers-Bradley, Nancy. "Diaphragm". En Encyclopedia of Women’s Health, 367–69. Boston, MA: Springer US, 2004. http://dx.doi.org/10.1007/978-0-306-48113-0_123.

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Eisenberg, Ronald L. "Diaphragm". En What Radiology Residents Need to Know: Chest Radiology, 271–77. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-16826-1_20.

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Tovar, Juan A. "Diaphragm". En Pediatric Surgery Digest, 305–22. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-540-34033-1_17.

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Leenen, Luke P. H. "Diaphragm". En Head, Thoracic, Abdominal, and Vascular Injuries, 257–62. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-540-88122-3_5.

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Thorek, Philip. "Diaphragm". En Anatomy in Surgery, 280–90. New York, NY: Springer New York, 1985. http://dx.doi.org/10.1007/978-1-4613-8286-7_12.

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Kavazis, Andreas N. y Ashley J. Smuder. "Diaphragm". En Encyclopedia of Exercise Medicine in Health and Disease, 247–50. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-540-29807-6_203.

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Maker, Vijay K. y Edgar D. Guzman-Arrieta. "Diaphragm". En Cognitive Pearls in General Surgery, 117–29. New York, NY: Springer New York, 2014. http://dx.doi.org/10.1007/978-1-4939-1850-8_6.

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Actas de conferencias sobre el tema "Diaphragm"

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Degtyareva, K. S., S. I. Il'ina y L. S. Sal'nikova. "Diaphragm Diaphragm Pumps". En Scientific trends: Questions of exact and technical sciences. L-Journal, 2020. http://dx.doi.org/10.18411/sciencepublic-12-08-2020-07.

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Kim, Moon, G. K. Ananthasuresh y Haim H. Bau. "Magnetically Actuated, Circular Diaphragm Pumps Fabricated With Low-Temperature, Co-Fired Ceramic Tapes and Kapton Polyimide Films: Experiments and Theory". En ASME 2001 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/imece2001/mems-23806.

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Abstract Magnetically actuated diaphragm pumps were fabricated with low temperature co-fired ceramic (LTCC) tapes and Kapton polyimide film. The pumps consisted of a chamber machined in a LTCC substrate. The chamber was covered either on one or both sides with Kapton diaphragms on which copper coils were patterned. The diaphragms were actuated by passing electric current through the coils in the presence of permanent magnets. Passive Kapton flap valves were used to direct fluid flow into and out of the chamber. The first design consisted of a single, circular diaphragm pump. In the second design, two circular diaphragms were used. The two diaphragms are deflected into and out of the pressure chamber simultaneously. Flow rates of up to 7 mL/min were measured. The static response of a circular diaphragm subjected to magnetic forces was computed using the finite element method (FEM). The effect of the copper coils on diaphragm stiffness was accounted for. The design parameters (the number of windings and the size and location of the magnet) needed to maximize the volumetric displacement were determined. At relatively high currents, the coils heated up significantly and caused the pump’s performance to deteriorate.
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Xu, Jinglei, Chao Li, Jiang Sha y Kunyuan Zhang. "The Design and Experimental Study of a Multi- Diaphragm Piezoelectric Synthetic Jet Actuator". En ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-43193.

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Considering the shortcoming and inability of the conventional piezoelectric synthetic jet actuator (PE-SJA), a novel multi-diaphragm PE-SJA was designed and made in this paper, and some detailed experimental study was carried out upon it. Using the hotwire anemometry, the optimum resonance frequency of the actuator was obtained. Then, under this special frequency, velocity magnitude was measured at different positions along the axis of the orifice. And then the orifice exit velocity of different numbers of diaphragm was measured, analysized and compared, which showed that the mean and peak axis velocity of one diaphragm PE-SJA were only the half of those of the five diaphragms PE-SJA., while the performance of three diaphragms PE-SJA was almost the same as that of the five diaphragms., which meant that although the performance of the PE-SJA increased with the number of the piezoelectric diaphragm, it was not in linearly ways. From the experimental result it was also shown that: For frequency f = 560Hz, the optimum diameter and depth of the orifice was 2.5mm and 2mm, respectively. Therefore, the optimum depth/diameter ratio was 0.8 for the present actuator and frequency. And then the performance of the multi-diaphragm PE-SJA with taper-jet exit orifice was much better than that of the straight orifice. Finally, the PIV was used to measure the structure of vortex of the flowfield.
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Khan, Mahbub y Brian Uy. "Finite element (FE) analysis of H-Beam – composite POSCO (P)-Box column joints with new inner diaphragms". En IABSE Congress, Christchurch 2021: Resilient technologies for sustainable infrastructure. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2021. http://dx.doi.org/10.2749/christchurch.2021.1289.

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<p>This paper presents a numerical investigation of a H-beam – composite P-box column joint fabricated with two new inner diaphragms and a continuous inner diaphragm. The main objective of the current research is to investigate the structural performance of the newly developed inner diaphragms of POSCO under a cyclic loading. Hysteretic behaviour of the composite joints is analysed to investigate the structural performance of the new and continuous inner diaphragms. Furthermore, yield line behaviour of the new inner diaphragms is investigated to predict the failure mode under tensile load. To produce a design criterion for the newly developed inner diaphragms and continuous inner diaphragm, yielding or predicted failure area of the inner diaphragms under tensile stress is utilised from the FE results.</p>
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Hasikin, K., N. Soin y F. Ibrahim. "Micro-diaphragm performance analysis for polyimide diaphragm". En 2010 IEEE International Conference on Semiconductor Electronics (ICSE). IEEE, 2010. http://dx.doi.org/10.1109/smelec.2010.5549367.

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Kim, Ki Hoon y Sang Sik Yang. "Fabrication and Test of an Electromagnetic Micro Actuator With a Planar Coil on a Parylene Diaphragm". En ASME 2000 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/imece2000-1104.

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Abstract This paper presents the fabrication and test results of an electromagnetic micro actuator for peristaltic micropumps. The actuator consists of a parylene diaphragm, spiral Cu coils and magnets. Parylene is waterproof and the Young’s modulus of it is small compared with metals or silicon and its compounds. So, it is adequate for the actuator diaphragm of a micropump. The deflection of the fabricated actuator diaphragm is measured using a laser displacement meter. The deflections of the flat and corrugated diaphragms are 20 μm and 30 μm at 1 Hz, respectively, when input current amplitude is 100 mA and duty ratio is 50%.
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Anderson, James H., Chuck Hildebrand y James H. Anderson. "An Effective Way for Maintenance Reduction and Vibration Elimination of Peaking Gas Turbines". En ASME 2006 Power Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/power2006-88116.

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A US power generation company had 36 similar high heat rate gas turbines in two of their plants. These units were used for peaking power in a large metropolitan area. On two of these units in the early 1990’s they tried switching from lubricated, gear-type couplings to single, machined diaphragm-type couplings for reduction of maintenance and improved flexibility. The gear couplings also caused a great deal of vibrations during startup, and many times units were shut down because of excessive vibrations. Due to the extreme thermal growth of these applications, along with the stop-start nature of the application, the couplings were required to handle enormous amounts of misalignment. While the standard diaphragm couplings seemed like a good choice for the application because of their large misalignment capability, they proved to be unable to handle the excessive offset movements caused by thermal growth. The problem with the standard diaphragm was that it was too stiff or in other words, the spring rate was too high. In one case the coupling failed catastrophically very quickly under normal running conditions. In the mid 1990’s the power company tried a different, unique style of diaphragm couplings that used multiple diaphragms with holes in them. The diaphragms were made of thin, uniform thickness steel instead of the more common machined ‘profile’ diaphragms. Because of the holes, these new diaphragms provided much more misalignment capability, and they also had far lower spring rates than the previous diaphragm couplings. The lower spring rates caused an enormous reduction in reactionary forces from the coupling, and they also eliminated many vibration problems caused by the original gear couplings. The overall effect of this discovery was for the company to begin changing all similar units to this type of coupling. Now these 36 units which previously had severe vibration problems during startup, run very reliably. They have also eliminated the need for maintenance, which was an issue with the original gear couplings.
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Kim, Moon, G. K. Ananthasuresh y Haim H. Bau. "Meso-Scale Electromagnetic Pumps Fabricated With Low-Temperature Co-Fired Ceramic Tapes and Kapton Polyimide Films". En ASME 2000 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/imece2000-1099.

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Abstract Meso-scale electromagnetically actuated reciprocating diaphragm pumps were fabricated with low-temperature co-fired ceramic (LTCC) tapes and Kapton polyimide film. One design of the pump consisted of a chamber machined in LTCC substrate layers. The chamber was covered on one side with a Kapton diaphragm on which copper coils were shaped. The diaphragm was electromagnetically actuated in the presence of a permanent magnet. Passive Kapton flap valves were used to direct fluid flow into and out of the chamber. In the second pump design, the chamber was covered on both sides with Kapton diaphragms. Coils were formed on both diaphragms and current was transmitted through these coils in opposite directions and in the presence of a permanent magnet. Data for flow rate as a function of actuation frequency is presented for the first pump design. Although the pump was not optimized, flow rates on the order of a few mL per minute were recorded.
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Wang, Guoping, Hualing Chen, Shemiao Qi, Jiuhui Wu y Lie Yu. "Study on Compensatory Magnitude of Axial Misalignment for Flexible Couplings Assembled by Interference Fit". En ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/gt2011-45347.

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In general, there are three kinds of common metal flexible couplings, such as diaphragm coupling, disc coupling and gear coupling. Gear couplings, compared with diaphragm couplings and disc couplings, usually have a little ability in compensating misalignments. Diaphragm couplings have nice compensatory ability in radial, angular and axial directions, especially muti-diaphragm couplings have better compensatory ability than disc couplings. Diaphragm couplings are also suitable for higher rotating speed than disc couplings. They are high technology products, are widely used in micro gas turbine. Joint way of a diaphragm coupling with a shaft usually uses bolts and interference fit. In this article, a flexible diaphragm coupling assembled by interference fit was taken as research object. By comparing three kinds of interference assembly forms of the coupling, a most reasonable form was chosen and its axial compensatory ability was treated as main research content. An idea that “established process of balances is the varied process of misalignment magnitude” was presented. Combining the idea and the characters of interference fit, new boundary conditions were confirmed via bringing assumed shearing forces, and then the physical model was established based on the new boundary conditions mentioned above. Two-step method, based on the physical model, was presented to solve the axial compensatory magnitude. Meanwhile centrifugal stress and torsional shearing stress of diaphragms of the coupling were also considered in the process of calculation. Finally an example was done to support the method. Some important conclusions were acquired by calculating, and they are significant for design of the flexible diaphragm couplings.
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Qiang, Xuhong, Yapeng Wu y Xu Jiang. "Fatigue Performance of Cracked Bridge Diaphragm Repaired by SMA/CFRP Composite Patch". En IABSE Congress, Nanjing 2022: Bridges and Structures: Connection, Integration and Harmonisation. Zurich, Switzerland: International Association for Bridge and Structural Engineering (IABSE), 2022. http://dx.doi.org/10.2749/nanjing.2022.1650.

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<p>Under long-term service conditions, fatigue cracks are easily generated at the arc-shape cutouts in diaphragm of the orthotropic steel bridge decks when subjected to vehicle-induced vibration and cyclical wheel loads. For repairing cracks in diaphragm, this paper proposes the carbon fiber reinforced polymer (CFRP) sheets patched crack-stop hole method and shape memory alloys (SMA)/CFRP composite patched crack-stop hole method which introduces prestress by activating SMA. Moreover, in the numerical study the diaphragm model and reinforcement schemes are introduced, and the corresponding finite element model is established. The failure modes and fatigue lives of diaphragm specimens under different repair methods were obtained and compared by fatigue loading tests. It can be found that the bonding of CFRP sheets and SMA/CFRP composite patches can effectively postone the initiation of fatigue cracks and inhibit the propagation of cracks, which are ideal repair methods for strengthening the fatigue cracks of diaphragms in orthotropic steel bridge decks.</p>
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Informes sobre el tema "Diaphragm"

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Ravindran, T. K. Sundari. A study of user perspectives on the diaphragm in an urban Indian setting. Population Council, 1995. http://dx.doi.org/10.31899/rh1995.1032.

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This study attempted to examine user perspectives regarding the desirability of the diaphragm as a contraceptive method when included among other methods distributed freely through a family planning (FP) clinic. It sought to introduce on an experimental basis, the diaphragm into an ongoing and well-established FP clinic to increase contraceptive choice. This was primarily a qualitative study aimed at understanding women's perceptions about the risks and benefits, the reasons for use of the diaphragm, and the practical difficulties of using it effectively. It also studied the influence of service delivery factors in acceptance of this method. The study was part of a larger project of the Gender, Reproductive Health, and Population Policies research program. Information dissemination on diaphragms and other contraceptive methods was part of a comprehensive community outreach program on reproductive health education. Based on the information provided and use of the diaphragm over a month women perceived the key advantages to be the absence of side effects and the facility of need-based use. In addition, as this report notes, the diaphragm answered the needs of women who wished to space as well those who wished to limit the number of children.
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Fleischman, Robert. Seismic Design Methodology Document for Precast Concrete Diaphragms. Precast/Prestressed Concrete Institute, 2014. http://dx.doi.org/10.15554/pci.rr.seis-023.

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The design procedure in PART 1 is part of a new seismic design methodology for precast concrete diaphragms. The design methodology and procedure are the product of a large multi-university research project initiated and guided by the Precast/Prestressed Concrete Institute (PCI) and co-funded by PCI, the National Science Foundation (NSF) and the Charles Pankow Foundation (CPF), termed the Diaphragm Seismic Design Methodology (DSDM) project.
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Gong, Xuan, Zhou Chen, Kui Yang, Chuntao Li, Songshan Feng, Mingyu Zhang, Zhixiong Liu, Hongshu Zhou y Zhenyan Li. Endoscopic Transsphenoidal Surgery for Infra-Diaphragmatic Craniopharyngiomas: Impact of Diaphragm Sellae Competence on Hypothalamic Injury. International Journal of Surgery, mayo de 2024. http://dx.doi.org/10.60122/j.ijs.2024.20.03.

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Objective: Investigate the impact of diaphragm sellae competence on surgical outcomes and risk factors for postoperative hypothalamic injury (HI) in patients undergoing endoscopic transsphenoidal surgery (ETS) for infra-diaphragmatic craniopharyngiomas (ICs). Methods: A retrospective analysis of 54 consecutive patients (2016-2023) with ICs treated by ETS was conducted. All tumors originated from the sellar region inferior to the diaphragm sellae and were classified into two subtypes in terms of diaphragm sellae competence: IC with competent diaphragm sellae (IC-CDS) and IC with incompetent diaphragm sellae (IC-IDS). Clinical features, intraoperative findings, and follow-up data were compared between subtypes. Postoperative HI was assessed using a magnetic resonance imaging-based scoring system. Results: Fifty-four patients (29 males, 25 females) were included in this study, with 12 (22.2%) under 18 years old. Overall, 35 cases were IC-CDS, while 19 were IC-IDS. Compared with IC-CDS, patients with IC-IDS tended to have hormone hypofunction before surgery (p = 0.03). Tumor volume in IC-IDS group (9.0 ± 8.6 cm3) was also higher than that in IC-CDS group (3.3 ±3.4 cm, p = 0.011). Thirty-seven patients underwent standard endoscopic transsphenoidal approach (SEA) and 17 underwent an extended endoscopic transsphenoidal approach (EEA). Gross total resection (GTR) was achieved in 50 cases (92.6%). Postoperative CSF leak was observed in four patients (7.4%). Permanent diabetes insipidus (DI) occurred in 13 patients (27.7%), six in IC-CDS and seven in IC-IDS. Postoperative HI occurred in 38.9% of patients. Univariate analysis revealed that large tumor size (p = 0.014), prior hypopituitarism (p = 0.048) and IC-IDS (p < 0.001) were significantly associated with postoperative HI. Multivariate analysis revealed that IC- IDS was the sole predictor of postoperative HI. Conclusion: To our knowledge, this is the largest case series in the literature to describe IC resected by endoscopic surgery in a single institution. Classification based on diaphragm sellae competence highlights distinct clinical features and surgical outcomes between IC-CDS and IC-IDS subtypes. Notably, IC-IDS is an independent risk factor for postoperative HI. Preoperative identification of subtype can guide surgical strategy and potentially minimize complications.
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Kautz, D. D., T. J. Ramos y J. R. Murchie. Engineering evaluation and thermal analysis of the W79 diaphragm seal weld. Office of Scientific and Technical Information (OSTI), mayo de 1994. http://dx.doi.org/10.2172/10163757.

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Grant, Charles. Diaphragm Walls as Permanent Basement Walls in Regions of High Seismicity. Deep Foundations Institute, junio de 2018. http://dx.doi.org/10.37308/cpf-2012-slwl-1.

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Reinforced concrete structural slurry walls have been used in the United States since the early 1960s. The typical practice, and one that makes the economics of slurry walls particularly attractive, is to design the walls to act as both temporary excavation support and permanent basement walls. They often serve as multi-story basements and below grade parking for buildings, for tunnels, subway stations, and other buried structures. One of the early applications was for a foundation for a subway station in San Francisco, but for the most part they have been used more extensively in regions of low seismicity. The purpose of this report is to investigate the requirements for extension of this practice to more common use in regions of high seismicity. Structural slurry walls are concrete walls constructed below the ground surface. In slurry wall construction, a trench is excavated using a rectangular clamshell bucket or other specialized equipment. During excavation, the trench is held open by introduction of a bentonite or polymer slurry. Steel reinforcement, if required, is lowered into the slurry-filled trench, and concrete is subsequently deposited by tremie, displacing the slurry. The length of trench open at any one time is limited to a typical maximum of about 20 to 24 feet by excavation stability and concrete placement volume considerations. Each individual concrete placement is referred to as a “panel,” and vertical construction joints separate the panels. Temporary “end-stops” are used as formwork to control the geometry of the panel joints, and horizontal reinforcement is discontinuous at the joints. Structural slurry panels range from 1.5 to 5.0 feet thick, 7 to 24 feet long, and up to 300 feet deep. In the United States, panels that are 2.0 to 3.5 feet thick and depths of 40 to 150 feet are commonplace. Structural basement walls support earth pressures acting laterally against the wall, dead and live loads acting vertically, and in-plane shear and flexure from wind and earthquake loads. The design of permanent slurry walls in regions of low or moderate seismicity is often limited to providing the strength necessary to resist out-of-plane soil pressures and vertical dead and live loads from the superstructure and basement framing. Although these walls also transfer in-plane lateral forces from the superstructure into the soils, the walls are often not specifically designed for these in-plane forces because their inherent strength is usually much greater than the forces being transferred. If resistance to in-plane forces acting on a wall required an increase in vertical reinforcement at the ends of a wall segment, an increase in the cap beam strength, or an increase in the horizontal reinforcement for shear strength, the overall design and construction approach would not vary significantly from current practice. Structural slurry walls have been used to a limited extent for buildings designed for high seismic risk, but there is reluctance on the part of design engineers to use them more often because of concern for how to design these walls to resist in-plane lateral forces, lack of code provisions for reinforcement detailing, and damage that may occur at panel joints. For buildings designed for high seismic risk, such as those assigned to Seismic Design Categories (SDC) D, E, and F as defined in Minimum Design Loads for Buildings and Other Structures (ASCE/SEI 7-10), in-plane shear and flexural actions may likely require modifications of a structural slurry wall only designed for out-of-plane soil pressures and vertical live and dead loads. Design would need to address in-plane lateral forces acting on structural slurry walls and the interaction of the in-plane actions with the out-of-plane and vertical actions. These issues are discussed in this report, and approaches to design for high seismic risk are presented.
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Pierce, Janet D. Lung and Diaphragm Damage at Varying Oxygen Levels and Ventilator Modes Pst Hemorrhagic. Fort Belvoir, VA: Defense Technical Information Center, diciembre de 2011. http://dx.doi.org/10.21236/ada633002.

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Crosland, Richard D. Effect of Arachidonic Acid on Twitch Tension of the Rat Phrenic Nerve- Diaphragm. Fort Belvoir, VA: Defense Technical Information Center, enero de 1992. http://dx.doi.org/10.21236/ada265570.

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McRae, D. S. y M. A. Zikry. Time Accurate Computation of Unsteady Shock Tunnel Flow with Coupled Diaphragm Ruptude Mechanics. Fort Belvoir, VA: Defense Technical Information Center, octubre de 1999. http://dx.doi.org/10.21236/ada378084.

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Briggs, Nicholas E., Robert Bailey Bond y Jerome F. Hajjar. Cyclic Behavior of Steel Headed Stud Anchors in Concrete-filled Steel Deck Diaphragms through Push-out Tests. Northeastern University. Department of Civil and Environmental Engineering., febrero de 2023. http://dx.doi.org/10.17760/d20476962.

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Earthquake disasters in the United States account for $6.1 billion of economic losses each year, much of which is directly linked to infrastructure damage. These natural disasters are unpredictable and represent one of the most difficult design problems in regard to constructing resilient infrastructure. Structural floor and roof diaphragms act as the horizontal portion of the lateral force resisting system (LFRS), distributing the seismically derived inertial loads out from the heavy concrete slabs to the vertical LFRS. Composite concrete-filled steel deck floor and roof diaphragms are ubiquitously used in commercial construction worldwide due to the ease of construction and cost-effective use of structural material. This report presents a series of composite steel deck diaphragm Push-out tests at full scale that explore the effect that cyclic loading has on the strength of steel headed stud anchors. The effect that cyclic loading has on structural performance is explored across the variation of material and geometric parameters in the Push-out specimens, such as concrete density, steel headed stud anchor placement and grouping, steel deck orientation, and edge conditions. As compared to prior tests in the literature, the push-out tests conducted in this work have an extended specimen length that includes four rows of studs along the length rather than the typical two rows of studs, and an ability to impose cyclic loading. This provides novel insight into force flows in the specimens, failure mechanisms, and load distribution between studs and stud groups.
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Peters, T. J., B. J. Hickman y J. B. Colson. Evaluation of bubbler/diaphragm techniques to measure surface level in the waste storage tanks. Office of Scientific and Technical Information (OSTI), octubre de 1993. http://dx.doi.org/10.2172/10192085.

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