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1
Zhao, Pin, e Jian Shu Ye. "Research on the Installation Lengths of Zero Block Concrete Segment in Prestressed Concrete Box-Girder Beams with Corrugated Steel Webs". Advanced Materials Research 255-260 (maggio 2011): 1147–53. http://dx.doi.org/10.4028/www.scientific.net/amr.255-260.1147.
Abstract (sommario):
In order to study the reasonable installation lengths of zero block concrete segment in prestressed concrete box-girder beams with corrugated steel webs, a numerical analysis on the length of different zero blocks in PC box girder beams with corrugated steel webs is made by the finite element software ANSYS. The influence of the installation lengths of zero block concrete segment on the structure control section's internal forces and deformation is discussed. The results indicate: the impact of length changes of zero block on box girder deflection is greater than its impact on internal forces; in terms of deflection, the displacement influence in quarter-section in middle span is the largest; and in terms of internal forces, the internal forces influence of the junction section formed by zero block concrete segment and beam segment with corrugated steel webs is the largest. According to the above results and the relevant information of constructed bridges, the reasonable setting length of zero block concrete segment has been provided, that the ratio L0/L of installation lengths and span for zero block of box girder should be in the range of 0.05 to 0.10.
2
Dahmer, Iulia, e Götz Kersting. "The internal branch lengths of the Kingman coalescent". Annals of Applied Probability 25, n. 3 (giugno 2015): 1325–48. http://dx.doi.org/10.1214/14-aap1024.
3
Ford, Jonathan, e Angelo Camerlenghi. "Geostatistical characterization of internal structure of mass-transport deposits from seismic reflection images and borehole logs". Geophysical Journal International 221, n. 1 (19 dicembre 2019): 318–33. http://dx.doi.org/10.1093/gji/ggz570.
Abstract (sommario):
SUMMARY Seismic reflection images of mass-transport deposits often show apparently chaotic, disorded or low-reflectivity internal seismic facies. The lack of laterally coherent reflections can prevent horizon-based interpretation of internal structure. This study instead inverts for geostatistical parameters which characterize the internal heterogeneity of mass-transport deposits from depth-domain seismic reflection images. A Bayesian Markov Chain Monte Carlo inversion is performed to estimate posterior probability distributions for each geostatistical parameter. If the internal heterogeneity approximates an anisotropic von Kármán random medium these parameters can describe the structural fabric of the imaged mass-transport deposit in terms of lateral and vertical dominant scale lengths and the Hurst number (roughness). To improve the discrimination between vertical and lateral dominant scale lengths an estimate of the vertical dominant scale length from a borehole is used as a prior in the inversion. The method is first demonstrated on a synthetic multichannel seismic reflection image. The vertical and lateral dominant scale lengths are estimated with lower uncertainty when data from a synthetic borehole data are included. We then apply the method to a real data example from Nankai Trough, offshore Japan, where a large mass-transport deposit is imaged in a seismic profile and penetrated by a borehole. The results of the inversion show a downslope shortening in lateral scale length, consistent with progressive down-slope disaggregation of the mass-flow during transport. The dominant scale lengths can be used as a proxy for strain history, which can improve understanding of post-failure dynamics and emplacement of subacqueous mass-movements, important for constraining the geohazard potential from future slope failure.
4
Li, Guoqi, Lifu Zhu, Yongjun Hu, Yingzi Jin, Toshiaki Setoguchi e Heuy Dong Kim. "Influence of Chord Lengths of Splitter Blades on Performance of Small Axial Flow Fan". Open Mechanical Engineering Journal 9, n. 1 (25 giugno 2015): 361–70. http://dx.doi.org/10.2174/1874155x01509010361.
Abstract (sommario):
On the basis of small axial fan with five blades, 6 types of small axial flow fans with different chord lengths splitter blades were designed. Numerical simulation of 6 fan models with splitter blades and prototype fan were done by using Fluent. Based on the obtained simulation results, internal flow characteristics and aerodynamic noise were analyzed and compared. It indicates that: splitter blades with suitable chord length have improved significantly on internal flow characteristics, which inhibits backflow from pressure surface to the suction surface at blade tip and leading edge and restrains flow separation. The 6 model fans are better than prototype fan on aerodynamic noise improvement, but too long or too short chord lengths are both disadvantage to improve aerodynamic noise. The results reveal that 2/6, 3/6 and 4/6 chord length model have relatively better acoustic characteristics and internal flow characteristics. The research program will offer a reference for structural improvements and noise reduction on small axial flow fan.
5
Kersting, Götz, Juan Carlos Pardo e Arno Siri-Jégousse. "Total internal and external lengths of the Bolthausen-Sznitman coalescent". Journal of Applied Probability 51, A (dicembre 2014): 73–86. http://dx.doi.org/10.1239/jap/1417528468.
Abstract (sommario):
In this paper we study a weak law of large numbers for the total internal length of the Bolthausen-Sznitman coalescent, thereby obtaining the weak limit law of the centered and rescaled total external length; this extends results obtained in Dhersin and Möhle (2013). An application to population genetics dealing with the total number of mutations in the genealogical tree is also given.
6
Kersting, Götz, Juan Carlos Pardo e Arno Siri-Jégousse. "Total internal and external lengths of the Bolthausen-Sznitman coalescent". Journal of Applied Probability 51, A (dicembre 2014): 73–86. http://dx.doi.org/10.1017/s0021900200021203.
Abstract (sommario):
In this paper we study a weak law of large numbers for the total internal length of the Bolthausen-Sznitman coalescent, thereby obtaining the weak limit law of the centered and rescaled total external length; this extends results obtained in Dhersin and Möhle (2013). An application to population genetics dealing with the total number of mutations in the genealogical tree is also given.
7
Mao, Boyan, Wenxin Wang, Bao Li, Xiaoyan Zhang e Youjun Liu. "Competitive Flow Effects of Internal Mammary Artery Bypass with Different Coronary Stenosis Lengths". International Journal of Computational Methods 16, n. 03 (17 marzo 2019): 1842013. http://dx.doi.org/10.1142/s0219876218420136.
Abstract (sommario):
In coronary artery bypass grafting (CABG), competitive flow usually happens when the native coronary has a moderate stenosis. But whether the competitive flow could be affected by the length of this moderate stenosis is still a problem. This study constructs a series of CABG models with different stenosis lengths and uses multi-scale modeling method for numerical simulations. The results contain graft flow, the magnitude of competitive flow, wall shear stress (WSS) and oscillating shear index (OSI). According to the results, it is known that the effect of competitive flow will decrease with the increase of stenosis length. But when the length reaches 15[Formula: see text]mm, the competitive flow will hardly change anymore.
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Sleboda, David A., e Thomas J. Roberts. "Internal fluid pressure influences muscle contractile force". Proceedings of the National Academy of Sciences 117, n. 3 (26 dicembre 2019): 1772–78. http://dx.doi.org/10.1073/pnas.1914433117.
Abstract (sommario):
Fluid fills intracellular, extracellular, and capillary spaces within muscle. During normal physiological activity, intramuscular fluid pressures develop as muscle exerts a portion of its developed force internally. These pressures, typically ranging between 10 and 250 mmHg, are rarely considered in mechanical models of muscle but have the potential to affect performance by influencing force and work produced during contraction. Here, we test a model of muscle structure in which intramuscular pressure directly influences contractile force. Using a pneumatic cuff, we pressurize muscle midcontraction at 260 mmHg and report the effect on isometric force. Pressurization reduced isometric force at short muscle lengths (e.g., −11.87% of P0 at 0.9 L0), increased force at long lengths (e.g., +3.08% of P0 at 1.25 L0), but had no effect at intermediate muscle lengths ∼1.1–1.15 L0. This variable response to pressurization was qualitatively mimicked by simple physical models of muscle morphology that displayed negative, positive, or neutral responses to pressurization depending on the orientation of reinforcing fibers representing extracellular matrix collagen. These findings show that pressurization can have immediate, significant effects on muscle contractile force and suggest that forces transmitted to the extracellular matrix via pressurized fluid may be important, but largely unacknowledged, determinants of muscle performance in vivo.
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Brüse, Sabine, J. Dee e W. D. Prieur. "Internal Fixation with a Veterinary Cuttable Plate in Small Animals". Veterinary and Comparative Orthopaedics and Traumatology 02, n. 01 (1989): 40–46. http://dx.doi.org/10.1055/s-0038-1633188.
Abstract (sommario):
Summary63 cases (42 cats, 21 dogs) were treated with a newly developed plate that can be cut during surgery to the required length and may be sandwiched if one plate is not rigid enough. The plate is manufactured in lengths of 30 cm and in two different thicknesses, 1.0 mm and 1.5 mm. The thinner plate is used with 1.5 mm or 2.0 mm Cortex screws and the thicker one with 2.0 or 2.7 mm Cortex screws. Healing was generally uneventful with the exceptions noted.
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Mahmoud, Hosam M. "Limiting Distributions for Path Lengths in Recursive Trees". Probability in the Engineering and Informational Sciences 5, n. 1 (gennaio 1991): 53–59. http://dx.doi.org/10.1017/s0269964800001881.
Abstract (sommario):
The depth of insertion and the internal path length of recursive trees are studied. Luc Devroye has recently shown that the depth of insertion in recursive trees is asymptotically normal. We give a direct alternative elementary proof of this fact. Furthermore, via the theory of martingales, we show that In, the internal path length of a recursive tree of order n, converges to a limiting distribution. In fact, we show that there exists a random variable I such that (In – n In n)/n→I almost surely and in quadratic mean, as n → α. The method admits, in passing, the calculation of the first two moments of In.
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Jeon, Daeje, Jungjin Park, Jaemyung Ryu e Hojong Choi. "Design of an Internal Focusing Tube Lens for Optical Inspection Systems". Applied Sciences 14, n. 4 (13 febbraio 2024): 1518. http://dx.doi.org/10.3390/app14041518.
Abstract (sommario):
The numerical aperture (NA) of objective lens optical (inspection) systems has been increased to achieve higher resolution. However, the depth of focus decreases with an increase in the NA, and focusing becomes difficult. Therefore, the entire optical lens in currently developed optical inspection systems must be moved to focus within the depth of focus. To achieve a high resolution, many lenses are used in optical inspection systems, increasing the size and weight of the optical systems. To address this issue, a focus control group was placed on a tube lens that could adjust its focus based on the movement of the sample in front of the objective lens. Therefore, we developed a focus range increment to focus on the range of the optical inspection system. Using objective lenses with focal lengths of 30 and 60 mm and tube lenses with a focal length of 300 mm, optical systems for 10× and 5× inspection were constructed. In the designed optical systems, the weights of the objective lenses with focal lengths of 30 and 60 mm were calculated to be approximately 844 and 570 g, respectively. These values confirm that the weight of the moving group can be reduced.
12
Gomes, Ricardo A. M. P., e Tarcisio B. Celestino. "Influence of physical and geometrical parameters on three-dimensional load transfer mechanism at tunnel face". Canadian Geotechnical Journal 46, n. 7 (luglio 2009): 855–68. http://dx.doi.org/10.1139/t09-016.
Abstract (sommario):
Three-dimensional discretizations used in numerical analyses of tunnel construction normally include excavation step lengths much shorter than tunnel cross-section dimensions. Simulations have usually worked around this problem by using excavation steps that are much larger than the actual physical steps used in a real tunnel excavation. In contrast, the analyses performed in this study were based on finely discretized meshes capable of reproducing the excavation lengths actually used in tunnels, and the results obtained for internal forces are up to 100% greater than those found in other analyses available in the literature. Whereas most reports conclude that internal forces depend on support delay length alone, this study shows that geometric path dependency (reflected by excavation round length) is very strong, even considering linear elasticity. Moreover, many other solutions found in the literature have also neglected the importance of the relative stiffness between the ground mass and support structure, probably owing to the relatively coarse meshes used in these studies. The analyses presented here show that relative stiffness may account for internal force discrepancies in the order of 60%. A dimensionless expression that takes all these parameters into account is presented as a good approximation for the load transfer mechanism at the tunnel face.
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Dulia, Mykhailo, e Olena Usychenko. "INTRODUCTION OF THE NATIONAL SYSTEM OF ACCOUNTING OF THE LENGTH OF HIGHWAYS IN SINGLE-LANE CALCULATION". Dorogi i mosti 2024, n. 29 (17 maggio 2024): 139–47. http://dx.doi.org/10.36100/dorogimosti2024.29.139.
Abstract (sommario):
Introduction. The use of geographical spatial data of the public road network has led to the question of the feasibility of applying existing methods of road length accounting and the need to introduce single-lane road length accounting. Problem statement. The search for alternative ways to account for the length of a road calls for improving the principles of forming road titles, which have certain solutions for accounting for sections with more than one lane in each direction and establishing the lengths of traffic interchanges, additional lanes on ascents, external and internal transitional high-speed lanes, dedicated (channelized) lanes, etc. Objective. To improve the system of accounting for the length of public roads of national importance. Materials and methods. The principles of road titling introduced in [1] have certain solutions for accounting for sections with more than 1 lane in each direction and establishing the lengths of traffic interchanges, which were rational at the time of adoption, but without further improvement may be ineffective and increasingly lead to contradictions. The need to introduce the term "length of a public road in single-lane calculation" is due to the fact that there are fundamental differences between the lengths of roads approved by the Resolution of the Cabinet of Ministers of Ukraine "On Approval of the List of Public Roads of National Importance" of December 15, 2023 No. 1318 [2] and the actual length (area) of lanes subject to repair and maintenance, since the road may have a different number of main lanes along its length, additional lanes on ascents, external and internal transitional high-speed lanes, dedicated (channelized) lanes, and exits may have several lanes in one direction.
14
Wang, Xiao Feng, Xiao Jun Zhou e Hong Yun Hu. "Study on Selection of the Length of Reinforced Concrete Segment for Oil and Gas Shield Tunnel with 3D Numerical Analysis". Applied Mechanics and Materials 488-489 (gennaio 2014): 517–20. http://dx.doi.org/10.4028/www.scientific.net/amm.488-489.517.
Abstract (sommario):
3D finite element analysis is utilized to calculate stress and internal forces in three different lengths of reinforced concrete segment for oil and gas shield tunnel subject to water and earth pressure by means of load-structure model. The rational length of concrete segment is determined to be 1.2m long after comparing the calculated stress and internal force in concrete segment with length of 1.0m, 1.2m and 1.5m respectively. Meanwhile, the safety factor is also compared in order to determine the rational length of concrete segment. The analysis shows that segment length for oil and gas shield tunnel with small cross-section should be less than 1.2m so as to facilitate its transportation and erection on construction site.
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Pradhan, Allin, Manish Man Pradhan, Rabita Kharbuja, Deepika Karki e Shaligram Dhungel. "Variations in Origin and Branching Pattern of Anterior Division of Internal Iliac Artery: a Cadaveric Study". Journal of College of Medical Sciences-Nepal 18, n. 2 (30 giugno 2022): 153–61. http://dx.doi.org/10.3126/jcmsn.v18i2.44309.
Abstract (sommario):
Introduction: Detailed knowledge of the branching pattern of internal iliac artery will be a guidance for ligating the artery and its branches during various pelvic surgeries. Hence, the main objective of this study was to know the branching pattern of internal iliac artery, based on the Adachis Classification along with the length and diameter of the arteries. Methods: The descriptive observational cross-sectional study was conducted at the Department of Human Anatomy of the Nepal medical college, examined over a period of 9 months from June 2021- February 2022 which included 30 internal iliac arteries and its branches of right and left sides from 15 embalmed male human cadavers. Results: In the study, branching pattern of internal iliac artery (IIA) was Type Ia in 19 (63.33%) and Type III in 11 (36.66%) of the cases while type I b, Type II a, Type II b, IV and V pattern were not observed. The total minimum and maximum lengths of both right and left trunk of internal iliac arteries were 1.33 cm and 3.42 cm respectively and average lengths with standard deviation were 2.61cm ± 0.66.The calculated P valve (0.002) showed that the differences between the lengths of IIA of both sides were statistically significant. The diameter and standard deviation of IIA and obturator artery were 6.37±1.33 and 2.47cm±0.67 respectively. The obturator artery was found to be originated from both anterior and posterior division of IIA accounting as 96.66% and 3.33% respectively. Conclusions: Pelvic surgeries may lead to hemorrhage if branching patterns of the IIA are incorrectly interpreted and thus endanger the patient’s life while ligating the artery during prostatectomy, hernioplasty. The current study explain the important aspects of the vascular anatomy of the IIA not only for anatomists and morphologists, but also for the radiologists, general and vascular surgeons. Key words: internal iliac artery; inferior gluteal artery; internal pudendal artery; obturator artery; variations.
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Mukerji, Nitin, Julian Cahill, Desiderio Rodrigues, Savithru Prakash e Roger Strachan. "Flow dynamics in lumboperitoneal shunts and their implications in vivo". Journal of Neurosurgery 111, n. 3 (settembre 2009): 632–37. http://dx.doi.org/10.3171/2009.2.jns08912.
Abstract (sommario):
Object Lumboperitoneal shunting is the standard treatment for pseudotumour cerebri or idiopathic intracranial hypertension. Complications are common, particularly the problem of overdrainage leading to low pressure symptoms. The authors designed a simple experiment using catheters of different lengths that drained at different pressure heads and with different vertical drops to study the flow characteristics in these shunts and determine the optimal catheter placement and length that would reduce the occurrence of low pressure headaches. Methods The flow rates through catheters of 3 different lengths (60, 83, and 100 cm) with the same internal radius, at 3 different pressure heads (15, 25, and 35 cm H2O to simulate 3 different placements in the lumbar theca), and 3 different vertical drops (10, 20, and 30 cm to simulate the possible effect of siphoning) were measured and the results analyzed. Results Application of Poiseuille's law and Bernoulli's principle to the experimental design shows that the volume of flow is directly proportional to the sum of the pressure head and the vertical drop and inversely proportional to the length of the catheter. The flow rate through the standard catheter lengths over the course of 24 hours can be abnormally high. An attempt to predict the optimal catheter length was made. Conclusions Although the catheter position in the theca and abdomen cannot be altered significantly and the internal radius of the tube cannot be reduced further without increasing the risk of blockage, the length of the tube can be increased to combat overdrainage. The authors suggest that currently available catheters are too short.
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Liu, Lei, Lianghan Zhang, Zhongxu Kang e Kun Yao. "Study on the Thermal Environment Inside a Fully-Enclosed Subway Noise Barrier". E3S Web of Conferences 143 (2020): 01044. http://dx.doi.org/10.1051/e3sconf/202014301044.
Abstract (sommario):
The thermal environment inside a fully-enclosed subway noise barrier shall be designed according to underground section tunnel standards. This article constructs a model using practical examples, simulates calculations on fully-enclosed noise barrier installations both with and without air vents via a threedimensional numerical simulation method, and then conducts a comparative analysis of the effects noise barrier lengths and air vent widths have on an internal thermal environment. The calculation results show that when the length of the fully-enclosed noise barrier without air vents was 100m, the internal thermal environment exceeded the limit; as the width of the air vents increased, the temperature in the internal environment gradually decreased, but the reduction was less once the air vent width exceeded 2 m; When the top air vent width was 2 m, and the noise barrier length was 100m, the thermal environment was found to meet requirements. As the noise barrier length increased, the internal air temperature exceeded the standards by varying degrees.
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Buffett, G. G., C. A. Hurich, E. A. Vsemirnova, R. W. Hobbs, V. Sallarès, R. Carbonell, D. Klaeschen e B. Biescas. "Stochastic Heterogeneity Mapping around a Mediterranean salt lens". Ocean Science 6, n. 1 (31 marzo 2010): 423–29. http://dx.doi.org/10.5194/os-6-423-2010.
Abstract (sommario):
Abstract. We present the first application of Stochastic Heterogeneity Mapping based on the band-limited von Kármán function to a seismic reflection stack of a Mediterranean water eddy (meddy), a large salt lens of Mediterranean water. This process extracts two stochastic parameters directly from the reflectivity field of the seismic data: the Hurst number, which ranges from 0 to 1, and the correlation length (scale length). Lower Hurst numbers represent a richer range of high wavenumbers and correspond to a broader range of heterogeneity in reflection events. The Hurst number estimate for the top of the meddy (0.39) compares well with recent theoretical work, which required values between 0.25 and 0.5 to model internal wave surfaces in open ocean conditions based on simulating a Garrett-Munk spectrum (GM76) slope of −2. The scale lengths obtained do not fit as well to seismic reflection events as those used in other studies to model internal waves. We suggest two explanations for this discrepancy: (1) due to the fact that the stochastic parameters are derived from the reflectivity field rather than the impedance field the estimated scale lengths may be underestimated, as has been reported; and (2) because the meddy seismic image is a two-dimensional slice of a complex and dynamic three-dimensional object, the derived scale lengths are biased to the direction of flow. Nonetheless, varying stochastic parameters, which correspond to different spectral slopes in the Garrett-Munk spectrum (horizontal wavenumber spectrum), can provide an estimate of different internal wave scales from seismic data alone. We hence introduce Stochastic Heterogeneity Mapping as a novel tool in physical oceanography.
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Ray, Alo, e Kurt W. Runge. "The Yeast Telomere Length Counting Machinery Is Sensitive to Sequences at the Telomere-Nontelomere Junction". Molecular and Cellular Biology 19, n. 1 (1 gennaio 1999): 31–45. http://dx.doi.org/10.1128/mcb.19.1.31.
Abstract (sommario):
ABSTRACT Saccharomyces cerevisiae telomeres consist of a continuous 325 ± 75-bp tract of the heterogeneous repeat TG1-3 which contains irregularly spaced, high-affinity sites for the protein Rap1p. Yeast cells monitor or count the number of telomeric Rap1p molecules in a negative feedback mechanism which modulates telomere length. To investigate the mechanism by which Rap1p molecules are counted, the continuous telomeric TG1-3 sequences were divided into internal TG1-3 sequences and a terminal tract separated by nontelomeric spacers of different lengths. While all of the internal sequences were counted as part of the terminal tract across a 38-bp spacer, a 138-bp disruption completely prevented the internal TG1-3 sequences from being considered part of the telomere and defined the terminal tract as a discrete entity separate from the subtelomeric sequences. We also used regularly spaced arrays of six Rap1p sites internal to the terminal TG1-3 repeats to show that each Rap1p molecule was counted as about 19 bp of TG1-3 in vivo and that cells could count Rap1p molecules with different spacings between tandem sites. As previous in vitro experiments had shown that telomeric Rap1p sites occur about once every 18 bp, all Rap1p molecules at the junction of telomeric and nontelomeric chromatin (the telomere-nontelomere junction) must participate in telomere length measurement. The conserved arrangement of these six Rap1p molecules at the telomere-nontelomere junction in independent transformants also caused the elongated TG1-3 tracts to be maintained at nearly identical lengths, showing that sequences at the telomere-nontelomere junction had an effect on length regulation. These results can be explained by a model in which telomeres beyond a threshold length form a folded structure that links the chromosome terminus to the telomere-nontelomere junction and prevents telomere elongation.
20
Koebley, Sean, Andrey Mikheikin, Kevin Leslie, Wendy McConnell-Wells, Joshua H. Lehman, Daniel Guest, Taha Al Juhaishi et al. "FLT3 Internal Tandem Duplication Quantitation and Length Analysis By Digital PCR Paired with High-Speed AFM". Blood 136, Supplement 1 (5 novembre 2020): 21–22. http://dx.doi.org/10.1182/blood-2020-137096.
Abstract (sommario):
Introduction DNA length polymorphisms are difficult to diagnose due to their repetitive or variable elements. Within the FLT3 gene, internal tandem duplications (ITDs) range from <30 bp to >200 bp in length and are associated with poor prognosis in acute myeloid leukemia (AML). To address these challenges, we developed digital polymerase chain reaction (dPCR) followed by high-speed atomic force microscopy (HSAFM) as a high-throughput, single-molecule approach for quantifying and sizing length polymorphisms associated with FLT3-ITDs. Methods In the first step of our approach, dPCR (Fig. 1A), a mixed sample is diluted and partitioned into micro-reactions that are individually amplified, mitigating amplification bias and producing homogeneous solutions of either wild-type (WT) or FLT3-ITD variant amplicons. We then used HSAFM to directly image individual amplicons and determine their lengths with nanoscale resolution (Fig. 1B). Length distributions were analyzed by Bayesian inference to identify their most likely character-WT or variant-by determining whether or not the 95% most credible range of mean lengths for each micro-reaction fell within a region of practical equivalence (ROPE) to WT length (Fig. 1C). Variant allele frequency (VAF) was then calculated as the proportion of variant-identified micro-reactions (Fig. 1D). We tested (a) synthetic and cell line DNA ranging from 30 bp to 217 bp, with VAF titrated down to 5%, and (b) clinical FLT3-ITD positive and negative samples, and compared dPCR-HSAFM results to those of a widespread clinical assay (Invivoscribe Leukostrat CDx FLT3 Mutation Assay). Results dPCR-HSAFM successfully returned the VAFs of all spiked-in FLT3-ITD samples across the admixture range of 5%-100%, and WT-only controls yielded VAFs of 0% (Fig. 1C,D). The four tested clinical samples determined as FLT3-ITD positive by the standard assay returned VAFs of 49%, 16%, 26%, and 61% by dPCR-HSAFM, while the two FLT3-ITD negative clinical samples returned VAFs of 6% and <1% (Fig. 1C). Mean variant length of control and clinical samples measured by dPCR-HSAFM agreed with the known lengths as reported by the Leukostrat assay or given by cell line documentation (Fig. 1C, horizontal lines). Conclusions By demonstrating accurate quantification and sizing of FLT3-ITD variants of clinically relevant size and VAF, dPCR-HSAFM supersedes the standard clinical assay, which does not report VAF. Since FLT3-ITD length and VAF are linked to AML outcome and are important for minimal residual disease following therapy, a test that provides both metrics is desirable. Furthermore, the speed, low cost, and flexibility of dPCR-HSAFM to detect long, repetitive insertions make it an attractive alternative to sequencing in the clinical diagnosis of FLT3-ITDs and other length polymorphisms. Figure 1. dCR-HSAFM technique and results. (A) Digital PCR of a mixed sample yields a homogeneous population of WT (blue) or variant FLT3-ITD (red) amplicons in each micro-reaction. (B) HSAFM images of DNA are traced with custom software to yield lengths of individual DNA molecules. (C) Length is used to classify each dPCR reaction as WT or variant, where each vertical line gives the 95% most credible range of mean length for a dPCR reaction and italicized numbers give the number of dPCR reactions for each sample. The four leftmost clinical samples were identified as FLT3-ITD positive by a standard clinical assay, while the two rightmost clinical samples were FLT3-ITD negative. The assay does not report VAF. (D) Spiked-in VAF v. detected VAF is shown for FLT3-ITD samples with 30 bp and 126 bp insertions, with spiked-in VAF ranging from 5%-100%. Vertical bars give the VAFs for ROPEs ± 10% of the initial ROPE width, which conveys the sensitivity of each VAF to the ROPE width. Figure 1 Disclosures No relevant conflicts of interest to declare.
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Wang, Fusheng, Zheng Wei, Pu Li, Lingjun Yu e Weichao Huang. "Initial Crack Propagation and the Influence Factors of Aircraft Pipe Pressure". Materials 12, n. 19 (23 settembre 2019): 3098. http://dx.doi.org/10.3390/ma12193098.
Abstract (sommario):
In aircraft engineering, an increase of internal pressure in a hydraulic pipe increases the probability of pipe damage, leading to crack propagation becoming a serious issue. In this study, the extended finite element method (XFEM) is applied to simulate initial crack propagation in hydraulic pipes and to investigate the influence factors. Stress intensity factors are extracted to verify the mesh independence of XFEM, which is based on the level set method and unit decomposition method. A total of 30 finite element models of hydraulic pipes with cracks are established. The distribution of von Mises stress under different initial crack lengths and internal pressures is obtained to analyze the change of load-carrying capacity in different conditions. Then, a total of 300 finite element models of hydraulic pipes with different initial crack sizes and locations are simulated under different working conditions. The relationship between the maximum opening displacement and crack length is analyzed by extracting the opening displacement under different initial crack lengths. The length and depth of the initial crack are changed to analyze the factors affecting crack propagation. The opening size and crack propagation length are obtained in different directions. The results show that radial propagation is more destructive than longitudinal propagation for hydraulic pipes in the initial stage of crack propagation.
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Li, Shijin, e Adrian R. Russell. "A sample formation procedure to obtain homogeneous post-erosion particle size distribution". E3S Web of Conferences 92 (2019): 02015. http://dx.doi.org/10.1051/e3sconf/20199202015.
Abstract (sommario):
Internal erosion (suffusion) is caused by water seeping through the matrix of coarse soil and progressively transporting out fine particles. The mechanical strength of soils within water retaining structures may be affected after internal erosion occurs. However, most experimental investigations on the mechanical consequences of internal erosion have used triaxial tests on samples having nonhomogeneous particle size distributions along their lengths. Such nonhomogeneities arise from the most commonly used sample formation procedure, in which seeping water enters one end of a sample and washes fine particles out the other. In this paper a new soil sample formation procedure is presented which results in homogeneous particle size distributions along the direction of seepage, that is at all locations along a sample's length.
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Kurkina, O. E., e T. G. Talipova. "Huge internal waves in the vicinity of the Spitsbergen Island (Barents Sea)". Natural Hazards and Earth System Sciences 11, n. 3 (25 marzo 2011): 981–86. http://dx.doi.org/10.5194/nhess-11-981-2011.
Abstract (sommario):
Abstract. The generation of huge amplitude internal waves by the barotropic tide in the Barents Sea at high latitudes is examined using the numerical model of the Euler 2-D equations for incompressible stratified fluid. The area considered is located between the Spitsbergen (Svalbard) Island and the Franz-Victoria Trough with a cross-section of 350 km length. There are two underwater hills about 100–150 m high on the background depth of about 300 m. It is shown that intensive nonlinear internal waves with amplitudes up to 50 m and lengths of about 6–12 km are generated in this zone. The total height of such waves is huge and they must be considered as a significant factor of the environment in this basin.
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Poole, MC, e DC Joyce. "A simple and reliable ethylene gassing system for plant studies". Australian Journal of Experimental Agriculture 33, n. 4 (1993): 507. http://dx.doi.org/10.1071/ea9930507.
Abstract (sommario):
An ethylene permeation system was tested in a study of flower abscission of Verticordia nitens (Lindley) Endl. Various concentrations of ethylene in air were generated by passing air, at a flow rate of 2 L/min, through chambers containing various lengths of polyvinyl chloride (PVC) tubing pressurised (50 kPa) with ethylene. Ethylene permeating through lengths of PVC tubing of 1.5, 15, 150, and 1500 cm (8 mm internal diameter, 1.5 mm wall thickness) gave ethylene concentrations in the outflow airstreams of 0.12, 0.99, 7.8, and 100 �L/L, respectively. Increasing the ethylene pressure in 150-cm-long tubing linearly increased the permeation of ethylene (0.07 �L/L. kPa). A log-linear abscission response of V. nitens flowers to increasing ethylene concentration was demonstrated using this system. Use of silicone tubing (8-mm internal diameter, 1.5-mm wall thickness) resulted in an ethylene flux 75 times that of the same length of PVC tubing. Higher flux through silicone tubing should allow development of ethylene permeation gassing systems suitable for use in fruit ripening and degreening rooms.
25
Shayan Asenjan, M., Ali Reza Sabet e M. Nekoomanesh. "Long fiber thermoplastic composites under high-velocity impact: Study of fiber length". Journal of Composite Materials 53, n. 3 (27 giugno 2018): 353–60. http://dx.doi.org/10.1177/0021998318784639.
Abstract (sommario):
This study experimentally investigates the high-velocity impact response of long glass fiber-reinforced polypropylenes with different fiber lengths. The study considers three long fiber thermoplastic composites, i.e. 5, 10, and 20 mm prepared via a combination of extrusion and pultrusion processes and a crosshead die. An internal mixer was used to obtain an isotropic compound. The dispersion quality of each compound was confirmed using burn off test. A gas gun with a spherical projectile was employed to conduct high-velocity impact tests at three velocities of 144, 205, and 240 m/s. Internal mixer operation resulted in extensive fiber length reduction for all three long fiber thermoplastic lengths. Results from mechanical tests (Tensile and Izod impact) revealed an increasing value with increase in long fiber thermoplastic length, i.e. fiber length. High-velocity impact results showed higher impact performance for 20 mm long fiber thermoplastic compound compared to 5 and 10 mm long fiber thermoplastic containing specimens. Rate of increase in energy absorption from neat polypropylene to 5 and 10 mm long fiber thermoplastic compounds is much higher than from 10 to 20 mm long fiber thermoplastics. High-velocity impact tests indicated that there may be a threshold value for fiber length beyond which the fiber length plays a lesser role. Scanning electron microscopic analysis showed more fiber breakage at the impact point at a higher impact velocity than the lower end of high-velocity impact.
26
Bendezu, H. C. P., N. K. Sakomura, E. B. Malheiros, R. M. Gous, N. T. Ferreira e J. B. K. Fernandes. "Modelling the egg components and internal cycle length of laying hens". Animal Production Science 59, n. 3 (2019): 420. http://dx.doi.org/10.1071/an17215.
Abstract (sommario):
A model that can estimate the changes that occur to the composition of egg components over time is an important tool for the nutritionists, since it can provide information about the nutrients required by a laying hen to achieve her potential egg output. In this context, the present study was aimed to model the potential egg production of laying hens during the egg-production period. One hundred and twenty Hy-Line W36 and ISA-Brown layers were used from 18 to 60 weeks of age, with each bird being an experimental unit. The birds were housed in individual cages during the experimental period. Egg production (%), egg weight (g) and the weight of egg components were recorded for each bird. The data were used to calculate the parameters of equations for predicting the weights of yolk, albumen and shell, and for predicting internal cycle length. The predicted results were evaluated by regressing residual (observed minus predicted) values of the predicted values centred of their average value. The equations for predicting mean yolk weight with age are for Hy-Line W36 (y1) and ISA-Brown (y2) respectively. Albumen and shell weights for Hy-Line W36 were described by the equations 15.07 × (yolk weight)0.37 and 0.70 × (yolk + albumen weight)0.50 respectively, and for ISA-Brown, 21.99 × (yolk weight)0.24 and 1.60 × (yolk + albumen weight)0.34 respectively. The average internal cycle length over time for Hy-Line W36 (ICL1) is described by the model 22.95 + 5.24 × (0.962t) + 0.02 × t and for ISA-Brown by 24.01 + 10.29 × (0.94t) + 0.004 × t, where t is the age at first egg (days). The assessment of the results indicated that the equations for predicting egg weight were more accurate for Hy-Line W36 but less precise for both strains, whereas the equation models for predicting the internal cycle lengths were more accurate and precise for ISA-Browns. The models could predict the potential weight of egg components and the rate of laying associated with the internal cycle lengths, and, on the basis of this information, it is possible to improve the nutrient requirement estimated.
27
Lee, Yong-Sang, Kyoung-Tak Kang e Dong-Hoo Han. "The non-linear FEM analysis of different connection lengths of internal connection abutment". Journal of Korean Academy of Prosthodontics 54, n. 2 (2016): 110. http://dx.doi.org/10.4047/jkap.2016.54.2.110.
28
Dong, Ronald Y., e G. M. Richards. "Modeling Internal Chain Dynamics in Nematogens of Different Chain Lengths: Deuteron NMR Study". Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals 262, n. 1 (marzo 1995): 339–55. http://dx.doi.org/10.1080/10587259508033537.
29
Meiss, Richard A., e Ramana M. Pidaparti. "Mechanical state of airway smooth muscle at very short lengths". Journal of Applied Physiology 96, n. 2 (febbraio 2004): 655–67. http://dx.doi.org/10.1152/japplphysiol.00388.2003.
Abstract (sommario):
Although the shortening of smooth muscle at physiological lengths is dominated by an interaction between external forces (loads) and internal forces, at very short lengths, internal forces appear to dominate the mechanical behavior of the active tissue. We tested the hypothesis that, under conditions of extreme shortening and low external force, the mechanical behavior of isolated canine tracheal smooth muscle tissue can be understood as a structure in which the force borne and exerted by the cross bridge and myofilament array is opposed by radially disposed connective tissue in the presence of an incompressible fluid matrix (cellular and extracellular). Strips of electrically stimulated tracheal muscle were allowed to shorten maximally under very low afterload, and large longitudinal sinusoidal vibrations (34 Hz, 1 s in duration, and up to 50% of the muscle length before vibration) were applied to highly shortened (active) tissue strips to produce reversible cross-bridge detachment. During the vibration, peak muscle force fell exponentially with successive forced elongations. After the episode, the muscle either extended itself or exerted a force against the tension transducer, depending on external conditions. The magnitude of this effect was proportional to the prior muscle stiffness and the amplitude of the vibration, indicating a recoil of strained connective tissue elements no longer opposed by cross-bridge forces. This behavior suggests that mechanical behavior at short lengths is dominated by tissue forces within a tensegrity-like structure made up of connective tissue, other extracellular matrix components, and active contractile elements.
30
Yunitasari, Savira, e Luciana Spica Almilia. "Internal Audit Decision Making and Belief Adjustment Model". Indonesian Accounting Review 13, n. 2 (13 settembre 2023): 277–91. http://dx.doi.org/10.14414/tiar.v13i2.3622.
Abstract (sommario):
This research aims to examine the disparities in audit choices between auditors who are exposed to positive news followed by negative news and those who are exposed to negative news followed by positive news. The investigation focuses on the End of Sequence presentation pattern as well as the lengths of information series (short and long). The study employed a mixed-design experimental approach, incorporating both between-subjects and within-subjects elements. The participants in the research comprised 124 undergraduate students from Accounting Hayam Wuruk Perbanas University. The results reveal that there is no distinction in audit decisions between participants who first receive positive news followed by negative news, and those who receive negative news followed by positive news in the End of Sequence presentation pattern. It also demonstrates that the arrangement of evidence (positive news followed by negative news or vice versa) and the length of information series (short or long) do not influence the decision-making of internal auditors in relation to the End of Sequence presentation pattern. Overall, the study findings refute the hypothesis proposed by Hogarth and Einhorn (1992) regarding the belief model revision, as they fail to support the notion that the End of Sequence presentation pattern induces primacy effects.
31
Gizzatullina, A. A., O. V. Mishchenkova e F. N. Pushkarev. "Applying the scalability apparatus to estimate the thermal efficiency of a single finned tube". Journal of Physics: Conference Series 2057, n. 1 (1 ottobre 2021): 012014. http://dx.doi.org/10.1088/1742-6596/2057/1/012014.
Abstract (sommario):
Abstract The paper explores the possibility of scaling the integral parameters of the cooling system operation using the working elements with the length from 0.01 to 0.5 m. Numerical solution of the conjugate problem of external aeromechanics, internal hydrodynamics and heat exchange is carried out. Parametric studies of the cooling process and aerodynamic resistance of finned tubular elements of various lengths are performed. As a result of generalization and unification of the computational experimental data, a numerical coefficient has been obtained to calculate the necessary integral characteristics for a cooling element of the assigned length.
32
Glavind, E. B., A. Forman, G. Madsen, D. Svane, K. E. Andersson e A. Tottrup. "Mechanical properties of isolated smooth muscle from human rectum and internal anal sphincter". American Journal of Physiology-Gastrointestinal and Liver Physiology 265, n. 4 (1 ottobre 1993): G792—G798. http://dx.doi.org/10.1152/ajpgi.1993.265.4.g792.
Abstract (sommario):
The passive and active length-tension relations of the circular smooth muscle layer of the human distal rectum and the proximal and distal internal anal sphincter were investigated. Muscle strips were prepared and mounted in organ baths for recording of isometric tension. Resting lengths (LR) were measured, and the preparations were elongated stepwise. At each length, the corresponding values for passive tension, spontaneous active resting tension, and the submaximal active tension were recorded. Elongations of 200-380% of LR were possible before a sharp increase in passive tension occurred. None of the mean tension values measured at length for maximal active tension (LO) differed significantly among the three muscle types. All strips developed active resting tension. This tension was myogenic and contributed 10 +/- 3, 23 +/- 6, and 27 +/- 6% to the total active performance of rectal and proximal and distal sphincter preparations, respectively. Collagen constituted approximately 50% of smooth muscle biopsies, with highest contents in distal internal anal sphincter. This study provides an acceptable method for assessing the optimal experimental length by stretching the strips in an inactive state to 200% of LR, followed by individual adjustment of the passive tension to 5 mN/mm2 measured at 200% of LR
33
Seo, Tae-Kun, Jeffrey L. Thorne, Masami Hasegawa e Hirohisa Kishino. "Estimation of Effective Population Size of HIV-1 Within a Host: A Pseudomaximum-Likelihood Approach". Genetics 160, n. 4 (1 aprile 2002): 1283–93. http://dx.doi.org/10.1093/genetics/160.4.1283.
Abstract (sommario):
Abstract Using pseudomaximum-likelihood approaches to phylogenetic inference and coalescent theory, we develop a computationally tractable method of estimating effective population size from serially sampled viral data. We show that the variance of the maximum-likelihood estimator of effective population size depends on the serial sampling design only because internal node times on a coalescent genealogy can be better estimated with some designs than with others. Given the internal node times and the number of sequences sampled, the variance of the maximum-likelihood estimator is independent of the serial sampling design. We then estimate the effective size of the HIV-1 population within nine hosts. If we assume that the mutation rate is 2.5 × 10−5 substitutions/generation and is the same in all patients, estimated generation lengths vary from 0.73 to 2.43 days/generation and the mean (1.47) is similar to the generation lengths estimated by other researchers. If we assume that generation length is 1.47 days and is the same in all patients, mutation rate estimates vary from 1.52 × 10−5 to 5.02 × 10−5. Our results indicate that effective viral population size and evolutionary rate per year are negatively correlated among HIV-1 patients.
34
Ahmed, Hamada Mohmed Abdelmotalib, Byung-Guk Ahn e Jeekeun Lee. "Numerical Simulations on the Performance of Two-Dimensional Serpentine Nozzle: Effect of Cone Mixer Angle and Aft-Deck". Aerospace 10, n. 1 (11 gennaio 2023): 76. http://dx.doi.org/10.3390/aerospace10010076.
Abstract (sommario):
The current study addresses the effect of different designs of the exhaust mixer and aft-deck on the performance of a two-dimensional convergent nozzle represented by the internal and external flows and heat transfer process. The effect of different exhaust mixer cone angles of 10°, 15°, and 20°, and different aft-deck lengths of 140 mm, 280 mm, and 420 mm on the nozzle performance was investigated. To address the effect of an aft-deck, the flow behavior of a nozzle with an aft-deck was compared to that of a nozzle without an aft-deck. Then, the effect of different aft-deck lengths and different aft-decks with rectangular and trapezoid shapes was investigated. The results demonstrated that increasing the mixer cone angle resulted in decreasing the high-temperature core flow and increasing the low-temperature bypass flow. Increasing the mixer cone angle resulted in reducing the velocity inside the nozzle and at the exhausted jet, which can reduce the noise generated by the engine. Furthermore, increasing the mixer cone angle decreased the internal temperature of the nozzle and, along with the exhausted jet, decreased the infrared radiation. The results also illustrated that the presence of the aft-deck resulted in decreasing the pressure, temperature, and velocity inside the nozzle. The aft-deck also decreased the length and size of the potential core. The aft-deck length had no clear effect on the internal flow. However, increasing the aft-deck length resulted in a decrease in the exhaust gas temperature, which can decrease the infrared radiation. On another hand, using trapezoid and triangle aft-deck can enhance the performance of the nozzle by decreasing the velocity and temperature inside the nozzle and at the exhausted jet.
35
WANG, CHENG-SHUN, YU-FANG CHEN e JING-JIN XIAO. "TRANSITION FREQUENCY OF STRONG-COUPLING IMPURITY BOUND POLARON IN AN ASYMMETRIC QUANTUM DOT". International Journal of Nanoscience 11, n. 03 (giugno 2012): 1250026. http://dx.doi.org/10.1142/s0219581x12500263.
Abstract (sommario):
Properties of the excited state of strong-coupling impurity bound polaron in an asymmetric quantum dot are studied by using linear combination operator and unitary transformation methods. The first internal excited state energy, the excitation energy and the transition frequency between the first internal excited and the ground states of the impurity bound polaron as functions of the transverse and the longitudinal effective confinement lengths of the dot, the electron–phonon coupling strength and the Coulomb bound potential were derived. Our numerical results show that they will increase with decreasing the effective confinement lengths, due to interesting quantum size confining effects. But they are an increasing functions of the Coulomb bound potential. The first internal excited state energy is a decreasing function of the electron–phonon coupling strength whereas the transition frequency and the excitation energy are an increasing one of the electron–phonon coupling strength.
36
Spiske, Felix, Martin Peter Dirauf e Andreas Siegfried Braeuer. "Aerogel-Lined Capillaries for Raman Signal Gain of Aqueous Mixtures". Sensors 22, n. 12 (10 giugno 2022): 4388. http://dx.doi.org/10.3390/s22124388.
Abstract (sommario):
We report an experimental study on the gain of the Raman signal of aqueous mixtures and liquid water when confined in aerogel-lined capillaries of various lengths of up to 20 cm and various internal diameters between 530 and 1000 µm. The lining was made of hydrophobised silica aerogel, and the carrier capillary body consisted of fused silica or borosilicate glass. Compared to the Raman signal detected from bulk liquid water with the same Raman probe, a Raman signal 27 times as large was detected when the liquid water was confined in a 20 cm-long capillary with an internal diameter of 700 µm. In comparison with silver-lined capillaries of the same length and same internal diameter, the aerogel-lined capillaries featured a superior Raman signal gain and a longer gain stability when exposed to mixtures of water, sugar, ethanol and acetic acid.
37
Choi, Young Hun, Jung-Eun Cheon, Seung Han Shin, Su-Mi Shin, So Mi Lee, Hyun-Hae Cho, Woo Sun Kim e In-One Kim. "Optimal insertion lengths of right and left internal jugular central venous catheters in children". Pediatric Radiology 45, n. 8 (17 marzo 2015): 1206–11. http://dx.doi.org/10.1007/s00247-015-3289-9.
38
Lee, Thomas H., Lawrence K. Gottlieb, Leslie J. Weitzman, Albert G. Mulley, Stephen G. Pauker e Barbara J. McNeil. "Lengths of stay of patients with uncomplicated acute myocardial infarction at three Boston hospitals". Journal of General Internal Medicine 3, n. 3 (maggio 1988): 239–44. http://dx.doi.org/10.1007/bf02596338.
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Chen, Yan, Ying Guo, Weidong Mi, Changsheng Zhang, Hong Wang, Dexu Zhao e Jiangbei Cao. "Anatomy of the right upper lobe revisited and clinical considerations in Chinese population". PLOS ONE 15, n. 11 (25 novembre 2020): e0242178. http://dx.doi.org/10.1371/journal.pone.0242178.
Abstract (sommario):
Objective The anatomy of the tracheobronchial tree differs among not only various races but also individual ethnic groups. Different lengths of the right mainstem bronchus (RMSB) had been described in previous publications. Since the differences in the anatomy of the RMSB and right upper lobe bronchus (RUB) may have clinical relevance when selecting devices, specifically, the right-side double lumen tube (R-DLT) for lung isolation, we revisited the anatomy of the right upper lobe in a large scale Chinese population. Methods In this retrospective cohort study, we reviewed 2093 consecutive adult patients undergoing thoracic computed tomography (CT) scans from data base in our hospital. Demographic characteristics were collected. The lengths, internal diameters, and angles of the RMSB and RUB were measured using reconstructive CT images. The correlations between the demographic variables and the RMSB length and diameters were also analyzed. Results The incidence of the aberrant RUB originated equal or above the tracheal carina was 8.1‰. 52.3% of the patients had a length of RMSB less than 23 mm, and the incidence of RMSB length <23 mm in women was significantly higher than that in men (63.5% vs. 42.8%, p = 0.000). The right bronchial length (RBL) was less than 10 mm in 21% of cases (17.8% in men and 24.8% in women, respectively, p = 0.000). Both the RMSB lengths and diameters had poor correlations with the heights in either male or female patients. Conclusion A much higher incidence of a shortened RMSB potentially make placement of a R-DLT more difficult in Chinese population. Both the lengths and diameters of the RMSB cannot be predicted by the height. Preoperative thoracic CT scan for each patient helps optimizing the selection of a lung isolation device, and the importance of an evaluation of the CT scans preoperatively by the anesthesiologists should be emphasized.
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Akhoundi, Behnam, e Vahid Modanloo. "Non-destructive evaluation of internal cracks in glass fiber reinforced composites using the laser shearing interferometry method". Дефектоскопия, n. 7 (15 luglio 2023): 44–57. http://dx.doi.org/10.31857/s0130308223070059.
Abstract (sommario):
Laser shearing interferometry is one of the new methods of non-destructive testing, which is based on the interference of monochromatic waves reflected from the surface of the sample. This method can evaluate the entire surface of the sample with high accuracy and speed, by directly measuring the out-of-plane displacement gradient. In this paper, the possibility of detecting subsurface cracks with various lengths and angles in composite samples has been investigated using the shearing method and thermal stimulation system. To this aim, artificial and controlled cracks of different lengths and angles were created in the manufactured composites. After validating the performance of the shearing arrangement, two radiation heat sources were used to apply the load on the samples. The effect of loading size variables, shearing size and direction, crack length, and their angle on the quality of the results was investigated. The results show that the change in loading size plays a more important role than the change in shearing size in correct crack detection. To achieve the best results in crack detection on the selected samples, optimal loading in thermal mode equal to 12 and 15 seconds from the front of the sample was obtained. Moreover, the optimal size of the shearing in the examined composite samples was estimated to be about 10% of the width of the image recorded by the camera. Using the optimized values, all subsurface cracks were identified.
41
Xu, Zhenfa, Fanyu Kong, Kun Zhang, Yinfeng Wang, Jiaqiong Wang e Ning Qiu. "Internal Flow Field and Loss Analysis of a Magnetic Drive Pump’s Cooling Circuit". Energies 16, n. 2 (11 gennaio 2023): 840. http://dx.doi.org/10.3390/en16020840.
Abstract (sommario):
The cooling circuit is an important component of the magnetic drive pump because it prevents demagnetization of the permanent magnet and damage to the containment shell owing to a high temperature increase. In this paper, the flow field and losses of the cooling circuit of the magnetic pump are discussed and experimentally verified based on numerical simulation methods. Five different lengths of magnetic couplings were designed, and the flow field distribution, cooling flow rate, and loss variation laws of the cooling circuit were analyzed. The results show that the pump flow rate and magnetic coupling length have a minimal effect on the velocity distribution in the cooling circuit. When the magnet length increases from 30 mm to 55 mm, the temperature rise of the cooling circuit and the pressure drop at the gap increase by 23.1% and 25.3%, respectively. When the length of the magnetic coupling remains constant, the cooling flow rate of the cooling circuit falls with an increasing pump flow rate, and it reduces by 8.4% when the pump flow rate increases from 0.7 Q to 1.3 Q. The water friction loss and eddy current loss of the cooling circuit increase with an increase in the magnetic coupling length, while the cooling flow rate decreases. When the magnet length increases from 30 mm to 55 mm, the eddy current losses in the coupling circuit and the water friction losses in the cooling circuit increase by 45% and 35%, respectively, while the cooling flow rate decreases by 13%.
42
Davidson, K. G. V., F. D. Moore e E. E. Roos. "299 ELECTROLYTE LEAKAGE FROM INDIVIDUAL MAIZE AND WHEAT SEEDS TO PREDICT GERMINATION PERCENTAGE AND RADICLE LENGTH". HortScience 29, n. 5 (maggio 1994): 473b—473. http://dx.doi.org/10.21273/hortsci.29.5.473b.
Abstract (sommario):
Multiple electroconductivity readings (μAmps) of leachates from individual seeds during the first 6 hr of imbibition was examined as a possible predictor of seed quality. Readings from each sample of 100 seeds were formed into frequency distributions and the mean, median. and internal slope were calculated using an automated computer retrieval system. Internal slope is a non-central tendency measure based on the slope of a line tangent to the inflection point of the S-shaped cumulative frequency distribution (CFD) of μAmps. Radicle lengths (3 days) and germination (7 days) percentages were regressed on each of the two measures of central tendency and also the CFD shape indicator, internal slope. None of the three predictors were satisfactory for estimating seed vigor (root lengths) of maize (Zea mays L.) or wheat (Triticum aestivum L.) or germination of wheat seed lots. Internal slope was useful in estimating viability of artificially aged maize seeds (r2= 0.91), which compared favorably with our previous results using naturally aged red clover (Trifolium pratense L.) seed lots. Overall the seed quality of the unaged wheat lots was fairly high and the electrolyte leakage test was not sensitive enough to detect differences within these lots.
43
Gao, Lei, Wei Xiao e Xin Ji. "Effect of glass fibers length on the properties of polytetrafluoroethylene composites reinforced by glass fibers and graphite: Experimental and simulation study". High Performance Polymers 34, n. 3 (8 dicembre 2021): 363–73. http://dx.doi.org/10.1177/09540083211059487.
Abstract (sommario):
Polytetrafluoroethylene (PTFE)-based matrix composites filled with glass fibers (GF) and graphite (GR) were prepared by an internal mixer and molded using a compression mold to produce test samples. The objective was to study the mechanical and tribological properties of PTFE composites filled with different lengths of GF. The fillers of GR and GF were 5 and 15 wt.%, respectively, with the lengths of the GF of 15, 20, 25, 30, and 35-μm in the work. The mechanical performance tests and tribological tests were carried out under the same conditions. The experimental results revealed that the mechanical properties and tribological properties of the PTFE composites filled with GF and GR were associated with the lengths of GF. When the length of GF increased from 15 to 20 μm, GF could be homogeneously dispersed in the PTFE-based matrix composites and the tensile strength reached the maximum value of 21.68 MPa. Also, with 20-μm long GF, the composites exhibited the lowest coefficient of friction values and wear rates compared to PTFE with GF of the other lengths. The changes in frictional heat generation and frictional force of the composites during sliding friction were simulated using the finite element method. The theoretical simulation results matched with the experimental values, which proved the accuracy of the theoretical simulations.
44
Lieberman, Edward B., Jinil Chang e Elena Shenk Prassas. "Formulation of Real-Time Control Policy for Oversaturated Arterials". Transportation Research Record: Journal of the Transportation Research Board 1727, n. 1 (gennaio 2000): 77–88. http://dx.doi.org/10.3141/1727-10.
Abstract (sommario):
The formulation of a real-time traffic control policy designed expressly for oversaturated arterials is presented, and the operating protocol is described. Its objectives are to ( a) maximize system throughput, ( b) fully use storage capacity, and ( c) provide equitable service. This control policy, known as RT/IMPOST (real-time/internal metering policy to optimize signal timing), is designed to control queue growth on every saturated approach by suitably metering traffic to maintain stable queues. Consistent with this approach, bounds on queue lengths and signal offsets are determined. A mixed-integer linear program (MILP) tableau is formulated to yield optimal values of signal offsets and queue length for each approach. A nonlinear (quadratic) programming formulation adjusts the arterial green-phase durations of each signal cycle so that the actual arterial queue lengths on each saturated approach will continually closely approximate the optimal queue lengths computed by the MILP formulation. The policy principles are as follows: ( a) the signal phase durations “meter” traffic at intersections servicing oversaturated approaches to control and stabilize queue lengths and to provide equitable service to competing traffic streams; and ( b) the signal coordination (i.e., offsets) controls the interaction between incoming platoons and standing queues in a way that fully uses the available storage capacity, keeps intersections clear of queue spillback, and maximizes throughput.
45
KAZHEKO, O. A., e M. V. BARANOVSKY. "INFLUENCE OF DIFFERENT LENGTHS OF MILK HOSES ON SANITARY AND HYGIENIC INDICATORS OF MILK". Zootechnical science of Belarus 57, n. 2 (25 settembre 2022): 110–21. http://dx.doi.org/10.47612/0134-9732-2022-57-2-110-121.
Abstract (sommario):
The article presents the results of research aimed at studying the effect of different lengths of milk hoses for pumping milk from the milking parlor to the cooling tank on the sanitary and hygienic indicators of milk. In the course of the work, the influence of different lengths (internal surface area) of milk transfer hoses on the total bacterial contamination of milk samples from a single milk yield was determined. In terms of titratable acidity, mechanical contamination and somatic cell content, milk corresponded to “Extra” grade.
46
Buffett, G. G., C. A. Hurich, E. A. Vsemirnova, R. W. Hobbs, V. Sallarès, R. Carbonell, D. Klaeschen e B. Biescas. "Stochastic heterogeneity mapping around a Mediterranean salt lens". Ocean Science Discussions 7, n. 1 (4 gennaio 2010): 1–15. http://dx.doi.org/10.5194/osd-7-1-2010.
Abstract (sommario):
Abstract. We present the first application of stochastic heterogeneity mapping based on the band-limited von Kármán function to a seismic reflection stack of a Mediterranean water eddy (meddy), a large salt lens of Mediterranean water. This process extracts two stochastic parameters directly from the reflectivity field of the seismic data: the Hurst number, which ranges from 0 to 1, and the correlation length (scale length). Lower Hurst numbers represent a richer range of scale lengths and correspond to a broader range of reflection events. The Hurst number estimate for the top of the meddy (0.39) compares well with recent theoretical work, which required values between 0.25 and 0.5 to model internal wave surfaces in open ocean conditions based on simulating a Garrett-Munk spectrum (GM76) slope of −2. Varying stochastic parameters, which correspond to different spectral slopes in the Garrett-Munk spectrum (horizontal wavenumber spectrum), can therefore provide an estimate of different internal wave scales from seismic data alone.
47
Yan, Pengmin, Xue Zhao, Jiuhou Rui, Juan Zhao, Min Xu e Lizhe Zhai. "Molecular Dynamics Simulation of the Influence of RDX Internal Defects on Sensitivity". Crystals 11, n. 4 (25 marzo 2021): 329. http://dx.doi.org/10.3390/cryst11040329.
Abstract (sommario):
The internal defect is an important factor that could influence the energy and safety properties of energetic materials. RDX samples of two qualities were characterized and simulated to reveal the influence of different defects on sensitivity. The internal defects were characterized with optical microscopy, Raman spectroscopy and microfocus X-ray computed tomography technology. The results show that high-density RDX has fewer defects and a more uniform distribution. Based on the characterization results, defect models with different defect rates and distribution were established. The simulation results show that the models with fewer internal defects lead to shorter N-NO2 maximum bond lengths and greater cohesive energy density (CED). The maximum bond length and CED can be used as the criterion for the relative sensitivity of RDX, and therefore defect models doped with different solvents are established. The results show that the models doped with propylene carbonate and acetone lead to higher sensitivity. This may help to select the solvent to prepare low-sensitivity RDX. The results reported in this paper are aiming at the development of a more convenient and low-cost method for studying the influence of internal defects on the sensitivity of energetic materials.
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Honjo, K., I. Furukawa e M. H. Sahri. "Radial Variation of Fiber Length Increment in ACACIA MANGIUM". IAWA Journal 26, n. 3 (15 luglio 2005): 339–52. http://dx.doi.org/10.1163/22941932-02603005.
Abstract (sommario):
The radial variation of fiber length increment (due to intrusive growth) and its relation with internal and external (climatic) factors were investigated for Acacia mangium trees collected in Indonesia and Malaysia. Wood fiber length and fiber length increment were approximated with respect to the distance from the pith (x) by a logarithmic function and vessel element length by a linear function. The results were y = 0.14 . In(x) + 0.48, y = 0.0005 . x + 0.20, and y = 0.13 . ln(x) + 0.31, respectively. The radial variation of fiber length was related to the growth rate rather than the age of the cambium. The results of the cross-correlation function between wood fiber length increment and climatic factors showed that fiber lengths responded to changes in precipitation with a time lag of between zero to four months.
49
Honjo, K., I. Furukawa e M. H. Sahri. "Radial Variation of Fiber Length Increment in Acacia Mangium". IAWA Journal 26, n. 3 (2005): 339–52. http://dx.doi.org/10.1163/22941932-90000119.
Abstract (sommario):
The radial variation of fiber length increment (due to intrusive growth) and its relation with internal and external (climatic) factors were investigated for Acacia mangium trees collected in Indonesia and Malaysia. Wood fiber length and fiber length increment were approximated with respect to the distance from the pith (x) by a logarithmic function and vessel element length by a linear function. The results were y = 0.14 . ln(x) + 0.48, y = 0.0005 . x + 0.20, and y = 0.13 . ln(x) + 0.31, respectively. The radial variation of fiber length was related to the growth rate rather than the age of the cambium. The results of the cross-correlation function between wood fiber length increment and climatic factors showed that fiber lengths responded to changes in precipitation with a time lag of between zero to four months.
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Jaafar, Jamiluddin, Januar P. Siregar, Ahmed N. Oumer, Mohammad Hazim Hamdan, Cionita Tezara e Mohd Sapuan Salit. "Experimental investigation on performance of short pineapple leaf fiber reinforced tapioca biopolymer composites". BioResources 13, n. 3 (5 luglio 2018): 6341–55. http://dx.doi.org/10.15376/biores.13.3.6341-6355.
Abstract (sommario):
The performance of short pineapple leaf fiber (PALF) reinforced tapioca biopolymer (TBP) composites were investigated, specifically the effect of fiber length and fiber composition on mechanical properties (tensile properties, flexural strength, and impact strength). Composite samples with different fiber lengths (< 0.50 mm, 0.51 mm to 1.00 mm, and 1.01 mm to 2.00 mm) and different fiber compositions (10%, 20%, 30%, and 40%) were prepared through crushing, sieving, internal mixing, compression molding, and machining processes. The combination of PALF and TBP enhanced the mechanical properties of composites with 30% as the optimum fiber content. However, the influence of different fiber lengths up to 2.00 mm provided no significant effect on producing maximum tensile properties. Good interfacial adhesion between PALF and TBP was evident from scanning electron microscopy analysis. Therefore, the combination of PALF and TBP has great potential as a renewable and biodegradable polymer. Moreover, PALF-TBP composites are expected to become alternatives to petroleum-based polymers.