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Zhang, Yilin, Zhenyu Cheng, and Qingsong He. "Time lag analysis of FDI spillover effect." International Journal of Emerging Markets 15, no. 4 (November 1, 2019): 629–50. http://dx.doi.org/10.1108/ijoem-03-2019-0225.
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Purpose For the developing countries involving in the Belt and Road Initiative (BRI) with China as the main source of foreign development investment (FDI) and development as the top priority, it appears to attract more and more attention on how to make the best use of China’s outward foreign development investment. However, the contradictory evidence in the previous studies of FDI spillover effect and the remarkable time-lag feature of spillovers motivate us to analyze the mechanism of FDI spillover effect. The paper aims to discuss this issue. Design/methodology/approach The mechanism of FDI spillovers and the unavoidable lag effect in this process are empirically analyzed. Based on the panel data from the Belt and Road developing countries (BRDCs) and China’s direct investments (CDIs) from 2003 to 2017, the authors establish a panel vector autoregressive model, employing impulse response function and variance decomposition analysis, together with Granger causality test. Findings Results suggest a dynamic interactive causality mechanism. First, CDI promotes the economic growth of BRDCs through technical efficiency, human capital and institutional transition with combined lags of five, nine and eight years. Second, improvements in the technical efficiency and institutional quality promote economic growth by facilitating the human capital with integrated delays of six and eight years. Third, China’s investment directly affects the economic growth of BRDCs, with a time lag of six years. The average time lag is about eight years. Originality/value Based on the analysis on the mechanism and time lag of FDI spillovers, the authors have shown that many previous articles using one-year lagged FDI to examine the spillover effect have systematic biases, which contributes to the research on the FDI spillover mechanism. It provides new views for host countries on how to make more effective use of FDI, especially for BRDCs using CDIs.
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Xie, Hongming, Jie Yang, Wei Yu, Yingnan Yang, and Wenshi Wu. "The Time-lag Effect of R&D Investment on the Value of Listed Companies in China: A Cross-industry Analysis." Journal of Creating Value 6, no. 2 (September 10, 2020): 217–31. http://dx.doi.org/10.1177/2394964320923543.
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Innovation plays an increasingly important role in economic growth, and R&D investment has become a key component of innovation initiatives. In this study, we performed analyses of 58 listed automobile manufacturers and 52 listed Internet companies in China. The empirical analysis is carried out by using STATA15.0 to preliminarily explore the mechanism of the time-lag effect of R&D investment on the value of these companies over the years of time-lag as well as conduct comparison analyses across industries. The results show that R&D investment has a positive effect on corporate value and this effect has a long-term time-lag effect. The mechanism of time-lag effect of R&D investment on the corporate value over the lag years has significant differences across industries. The time-lag effect of R&D investment on the value of the listed automobile manufacturer presents an inverted U shape, while the time-lag effect of R&D investment on the value of the listed Internet companies decreases gradually. The study helps local government better understand the different mechanisms of the time-lag effect of R&D investment on the value of the listed companies and also serves as a reference for local government to make decisions on subsidies and other supportive policies for innovation initiatives of the listed companies.
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Gursul, Ismet. "Proposed Mechanism for Time Lag of Vortex Breakdown Location in Unsteady Flows." Journal of Aircraft 37, no. 4 (July 2000): 733–36. http://dx.doi.org/10.2514/2.2661.
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Man, Shuai. "Surface Settlement Time Lag Induced by Shield Tunneling in Urban Sandy-Pebble Stratum." Applied Mechanics and Materials 405-408 (September 2013): 1326–29. http://dx.doi.org/10.4028/www.scientific.net/amm.405-408.1326.
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This paper focuses on the surface settlement time lag caused by shield tunneling in sandy-pebble stratum in Chengdu. A surface collapse case during Chengdu metro construction was introduced and the mechanism of surface settlement time lag was analyzed. The process of the ground settlement was simulated using the UDEC software. It is found that: 1) over-excavation and the grouting failure are the root causes of surface settlement; 2) characteristics of the sandy-pebble stratum in Chengdu induce ground voids behind tunnel segmental lining; 3) the mechanism of surface settlement time lag can be explained by temporary ground arch in the sandy-pebble stratum.
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Zhang, M., Yun Huang, and L. Zhang. "Research on the Mechanism of Coordinate Polishing Crankshaft Crankpin with Abrasive Belt." Key Engineering Materials 487 (July 2011): 457–61. http://dx.doi.org/10.4028/www.scientific.net/kem.487.457.
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Under the conditions of crankshaft uniform rotation, the schematic diagram of coordinate polishing crankpin was analyzed and found that the grinding time and speech changed, when the abrasive grinded crankpin. At the same time, the surface roughness was the relevant with the grinding time, grinding for a long time the roughness value was low, grinding time was short then the roughness value was high. In order to ensure that the surface roughness was homogeneity, so that the abrasive grinded the grinding point in the same time, in other words, the abrasive grinded crankpin in the constant velocity. And then the abrasive grinding crankpin was analyzed in the constant velocity, the crankshaft angle was draw the relationship between horizontal displacement and the swing angle. Simultaneity, adopted the level cylinder and the oscillating cylinder mutual moving, that resulted in the mechanism following the rotation of crankshaft back and forth movement, it was due to the weight of mechanism and the lag of the cylinder, and finally the mechanism of lag error was analyzed.
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Young, Lydia M., Ling-Hsien Tu, Daniel P. Raleigh, Alison E. Ashcroft, and Sheena E. Radford. "Understanding co-polymerization in amyloid formation by direct observation of mixed oligomers." Chemical Science 8, no. 7 (2017): 5030–40. http://dx.doi.org/10.1039/c7sc00620a.
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Tzou, D. Y. "A Unified Field Approach for Heat Conduction From Macro- to Micro-Scales." Journal of Heat Transfer 117, no. 1 (February 1, 1995): 8–16. http://dx.doi.org/10.1115/1.2822329.
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A universal constitutive equation between the heat flux vector and the temperature gradient is proposed to cover the fundamental behaviors of diffusion (macroscopic in both space and time), wave (macroscopic in space but microscopic in time), phonon–electron interactions (microscopic in both space and time), and pure phonon scattering. The model is generalized from the dual-phase-lag concept accounting for the lagging behavior in the high-rate response. While the phase lag of the heat flux captures the small-scale response in time, the phase lag of the temperature gradient captures the small-scale response in space. The universal form of the energy equation facilitates identifications of the physical parameters governing the transition from one mechanism (such as diffusion or wave) to another (the phonon–electron interaction).
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Dolas, Ramdas T., Shalindra Sharma, and Madhuraj Sharma. "FORMULATION AND EVALUATION OF GASTRORETENTIVE FLOATING TABLETS OF LAFUTIDINE." Journal of Drug Delivery and Therapeutics 8, no. 5 (September 11, 2018): 393–99. http://dx.doi.org/10.22270/jddt.v8i5.1898.
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The purpose of this research was to develop a novel gastroretentive drug delivery system based on wet granulation technique for sustained delivery of active agent. Quick GI transit could result in incomplete drug release from the drug delivery system above the absorption zone leading to decreased efficacy of the administered dose and thus less patient compliance. Gastroretentive floating tablets, which was designed to provide the desired sustained and complete release of drug for prolonged period of time. Gastroretentive floating tablets of lafutidine were prepared by wet granulation technique using different concentrations of Gum Kondagagu, Gum olibanum and Locust bean Gum. The optimized formulation (LF14) exhibited 99.54% drug release in 12 hrs, while the buoyancy lag time was 33 sec. In-vitro drug release kinetics was found to follow both the Zero order and the possible mechanism of lafutidine release from the optimized formulation might be attributed to super case II transport mechanism. The Optimized formulation (LF14) showed no significant change in physical appearance, drug content, floating lag time, in vitro dissolution studies after 75%±5% RH at 40±20C relative humidity for 6 months.
Keyword: Wet granulation, Floating lag Time, Gastroretentive, Lafutidine
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Su, Hui, J. David Neelin, and Joyce E. Meyerson. "Mechanisms for Lagged Atmospheric Response to ENSO SST Forcing*." Journal of Climate 18, no. 20 (October 15, 2005): 4195–215. http://dx.doi.org/10.1175/jcli3514.1.
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Abstract The mechanism and sensitivity of the lagged response of tropical tropospheric temperature to El Niño–Southern Oscillation (ENSO) SST forcing are examined using the Quasi-Equilibrium Tropical Circulation Model (QTCM) coupled to a slab mixed layer ocean model, along with a simple analytical model. It is found that the lag and amplitude of tropospheric temperature response depend on mixed layer depth (MLD), ENSO SST forcing period, areal fraction of the mixed layer ocean, and the strength of Tropics to midlatitude transports. The phase lag is not a monotonic function of mixed layer depth. It maximizes at moderate MLD and, thus, is not very sensitive to MLD in the realistic range. The phase lag asymptotes to values determined by free-atmospheric time scales, between 1 and 2 months, for small or large values of MLD. The amplitude of the tropospheric temperature response decreases with increasing MLD. The phase lag and amplitude of tropospheric temperature both increase as a specified ENSO SST forcing period increases and they appear to be rather insensitive to the seasonal cycle of SST. On the other hand, the phase lag and amplitude of mixed layer ocean SST change monotonically with MLD and ENSO forcing period, with a deeper mixed layer producing longer lag and smaller amplitude of SST anomalies. Longer ENSO SST forcing periods correspond to longer lag and larger amplitude of mixed layer ocean SST anomalies. While the ENSO region convective heating (precipitation) anomalies are closely tied to SST anomalies, the tropical mean precipitation seems best viewed as a complex by-product of the response rather than as a driver. One useful parameter determining the lag of tropospheric temperature to ENSO SST is the freedecay time scale of the coupled system. This parameter combines the effects of surface flux exchanges, heat loss at the top of the atmosphere and from the Tropics to midlatitudes, and finite ocean heat capacity. It is indicative of the extent to which the lagged response of tropical tropospheric temperature to ENSO SST is a coupled phenomenon. Overall, the contribution of coupling to SST outside the ENSO region substantially increases the amplitude and lag of the tropospheric temperature response to ENSO.
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Peng, Shun Lei, Peng Li, and Wen Hui You. "Time Lag Effects and Rainfall Redistribution in Subtropical Evergreen Broad-Leaved Forest in Eastern Coastal China." Advanced Materials Research 864-867 (December 2013): 2224–31. http://dx.doi.org/10.4028/www.scientific.net/amr.864-867.2224.
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In order to reveal the ecological mechanism of rainfall redistribution and lag effects on precipitation of evergreen broad leaved forest in eastern coastal China, 25 m×25 m permanent plot studies were carried inC. fargesiistand andS. Superbastand in Forest Ecosystem Observation and Research station in Tiantong, Zhejiang Province. The results indicated that the total rainfall outside the forest was 5114.0 mm, the average rates of canopy interception, throuhfall, and stemflow were 24.5%, 6.1%, and 69.4% respectively inC. fargesiistand, which were 30.7%, 7.7%, and 61.6% respectively inS. Superbastand. Rainfall redistribution function ofC. fargesiistand was better than that ofC. fargesiistand. Throughfall and stemflow were increased with rainfall class increasing while canopy interception decreased as rainfall class increasing, especially during typhoon storm period. throughfall was observed after 67.6min when rainfall classes<5 mm happened, while throughfall was observed after 11.8 min when special heavy storm happened inC. fargesiistand, 6 times shorter than little rainfall event. The lag time of throughfall inS. Superbastand was longer than that in theC. fargesiistand. The time lag shortened gradually as rainfall class increased. Lag time of stemflow was about 2 times than that of throughfall.
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Li, Bing-Hui, Rui Zhang, Ya-Tao Du, Ying-Hui Sun, and Wei-Xi Tian. "Inactivation mechanism of the β-ketoacyl-[acyl carrier protein] reductase of bacterial type-II fatty acid synthase by epigallocatechin gallate." Biochemistry and Cell Biology 84, no. 5 (October 2006): 755–62. http://dx.doi.org/10.1139/o06-047.
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Epigallocatechin gallate (EGCG), a major compound from green tea, reversibly inhibits β-ketoacyl-[acyl carrier protein] reductase (FabG) from Escherichia coli. In this study, we found that EGCG exhibited an atypical time-dependent inhibition of FabG, which possibly resulted from the EGCG-induced aggregation of FabG. It was observed that FabG inactivation and aggregation occurred nearly simultaneously, with a lag time that decreased with increasing EGCG concentration. These results suggest that some chemical reactions, required for aggregation and inactivation, occurred during the lag time. Since EGC was detected by HPLC after the incubation of EGCG with FabG, EGCG probably covalently modified FabG. These further results showed that 1 tetramer of FabG must be modified by several, possibly 4, EGCG molecules before the formation of FabG aggregates. FabG aggregation was a first-order reaction independent of protein concentration. Due to an initial lag time, the first-order rate of aggregation gradually increased, reaching a maximal and constant value. The effect of increasing concentration of EGCG on the first-order rate constant for aggregation indicated that EGCG bound to FabG by affinity labeling. Based on the results, we propose a mechanism for the interaction of EGCG with FabG:EGCG first binds reversibly to each subunit of FabG, followed by covalent modification and then aggregation of the 4 EGCG-modified subunits.
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Simanjuntak, Martin, and Budi Santosa. "PERBANDINGAN EFEKTIVITAS MEKANISME TRANSMISI KEBIJAKAN MONETER ANTARA JALUR SUKU BUNGA DENGAN JALUR NILAI TUKAR TERHADAP SASARAN AKHIR INFLASI." Media Ekonomi 25, no. 1 (August 7, 2019): 1. http://dx.doi.org/10.25105/me.v25i1.5199.
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<em>This result discusses the effectiveness of the transmission mechanism of monetary policy by comparing the interest rate channel with the exchange rate channel towards the final inflation taget. </em><em>This study using regression method Vector Error Correction Model (VECM). In the study of this monetary policy transmission mechanism using secondary data based on monthly time series, namely from January 2011 to December 2015. The data is obtained from Bank Indonesia Financial Economic Statistics (SEKI).</em> <em>From the results of this research, the transmission mechanism of monetary policy exchange rate channel is more effective than monetary policy transmission mechanism interest rate channel; it is proven through the test impulse responses and variance decomposition test. In the exchange rate channel time lag until reach the final target of monetary policy (inflation) is 4 months while for the interest rate channel time lag until reach the final target of monetary policy is 5 months. RPUAB very suitable for use as an operational target in the monetary policy transmission mechanism cause rapid and strong response from RPUAB in responding the shock of monetary policy. RPUAB is the biggest variable that dominates the formation of inflation.</em>
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Liu, Xiangyi, Shuyan Liu, Jing Wu, Shansong Song, and Guocai Hu. "An Analytical Method for Coaxial Helicopter Ground Resonance." MATEC Web of Conferences 316 (2020): 04005. http://dx.doi.org/10.1051/matecconf/202031604005.
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A time-frequency analytical method is presented to analyze physical mechanism of coaxial helicopter ground resonance. Eigenvalue calculation and numerical integration of disturbance equations of motions are used to obtain modal characters and time-domain response characters of coaxial helicopter ground resonance, and the interaction between rotors and body is revealed according to response of various DOFs. The analysis results show that regressive lag mode with upper rotor character is the most instability mode. In dynamic instability region, coaxial helicopter ground resonance is mainly due to energy transferred between periodic lag motion of upper rotor and body roll rotation. For this instability mode, energy transferred between periodic lag motion of lower rotor and body roll rotation is also existed, and it can enhance ground resonance instability of coaxial helicopter.
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Pradhan, Nrusingh Charan, Pramod Kumar Sahoo, Dilip Kumar Kushwaha, Indra Mani, Ankur Srivastava, Atish Sagar, Nikul Kumari, Susheel Kumar Sarkar, and Yash Makwana. "A Novel Approach for Development and Evaluation of LiDAR Navigated Electronic Maize Seeding System Using Check Row Quality Index." Sensors 21, no. 17 (September 3, 2021): 5934. http://dx.doi.org/10.3390/s21175934.
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Crop geometry plays a vital role in ensuring proper plant growth and yield. Check row planting allows adequate space for weeding in both direction and allowing sunlight down to the bottom of the crop. Therefore, a light detection and ranging (LiDAR) navigated electronic seed metering system for check row planting of maize seeds was developed. The system is comprised of a LiDAR-based distance measurement unit, electronic seed metering mechanism and a wireless communication system. The electronic seed metering mechanism was evaluated in the laboratory for five different cell sizes (8.80, 9.73, 10.82, 11.90 and 12.83 mm) and linear cell speed (89.15, 99.46, 111.44, 123.41 and 133.72 mm·s−1). The research shows the optimised values for the cell size and linear speed of cell were found to be 11.90 mm and 99.46 mm·s−1 respectively. A light dependent resistor (LDR) and light emitting diode (LED)-based seed flow sensing system was developed to measure the lag time of seed flow from seed metering box to bottom of seed tube. The average lag time of seed fall was observed as 251.2 ± 5.39 ms at an optimised linear speed of cell of 99.46 mm·s−1 and forward speed of 2 km·h−1. This lag time was minimized by advancing the seed drop on the basis of forward speed of tractor, lag time and targeted position. A check row quality index (ICRQ) was developed to evaluate check row planter. While evaluating the developed system at different forward speeds (i.e., 2, 3 and 5 km·h−1), higher standard deviation (14.14%) of check row quality index was observed at forward speed of 5 km·h−1.
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M. N, Ripdian Nisa, Banatul Hayati, and Edy Yusuf A. G. "Effectiveness of Monetary Policy Transmission Mechanism in Indonesia." JEJAK 11, no. 1 (March 10, 2018): 189–206. http://dx.doi.org/10.15294/jejak.v11i1.12385.
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This research aimed to analyse monetary mechanism effectivity to manage inflation in Indonesia through interest rate channel, credit channel, and expectation inflation channel. The research used Vector Error Correction Model (VECM) to analyze effectiveness of monetary policy transmission mechanism in Indonesia. The most effective channel was measured by result of Impulse Response Function and Variance Decomposition. They are: (1). The fastest time lag needed since the shock of monetary instruments (rSBI) until the realization of final target of monetary policy (inflation). (2). How strong the variables in each channel response the shock of SBI interest rate and other variable. The data used in this research is quarterly time series dara from 2005Q1 until 2016Q4. The results of this research show that the most effective channel in managing inflation during 2005Q1 until 2016Q4 is inflation expectation channel.
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Palombo, Daniela J., Joseph M. Di Lascio, Marc W. Howard, and Mieke Verfaellie. "Medial Temporal Lobe Amnesia Is Associated with a Deficit in Recovering Temporal Context." Journal of Cognitive Neuroscience 31, no. 2 (February 2019): 236–48. http://dx.doi.org/10.1162/jocn_a_01344.
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Medial-temporal lobe (MTL) lesions are associated with severe impairments in episodic memory. In the framework of the temporal context model, the hypothesized mechanism for episodic memory is the reinstatement of a prior experienced context (i.e., “jump back in time”), which relies upon the MTL [Howard, M. W., Fotedar, M. S., Datey, A. V., & Hasselmo, M. E. The temporal context model in spatial navigation and relational learning: Toward a common explanation of medial temporal lobe function across domains. Psychological Review, 112, 75–116, 2005]. This hypothesis has proven difficult to test in amnesia because of the floor-level performance by patients in recall tasks. To circumvent this issue, in this study, we used a “looped-list” format, in which a set of verbal stimuli was presented multiple times in a consistent order. This allowed for comparison of statistical properties such as probability of first recall and lag-conditional response probability (lag-CRP) between amnesic patients and healthy controls. Results revealed that the lag-CRP, but not the probability of first recall, is altered in amnesia, suggesting a selective disruption of temporal contiguity. To further characterize the results, we fit a scale-invariant version of the temporal context model [Howard, M. W., Shankar, K. H., Aue, W. R., & Criss, A. H. A distributed representation of internal time. Psychological Review, 122, 24–53, 2015] to the probability of first recall and lag-CRP curves. The modeling results suggested that the deficit in temporal contiguity in amnesia is best described as a failure to recover temporal context. These results provide the first direct evidence for an impairment in a jump-back-in-time mechanism in patients with MTL amnesia.
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Barthe, Manon, Josué Tchouanti, Pedro Henrique Gomes, Carine Bideaux, Delphine Lestrade, Carl Graham, Jean-Philippe Steyer, et al. "Availability of the Molecular Switch XylR Controls Phenotypic Heterogeneity and Lag Duration during Escherichia coli Adaptation from Glucose to Xylose." mBio 11, no. 6 (December 22, 2020): e02938-20. http://dx.doi.org/10.1128/mbio.02938-20.
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ABSTRACTThe glucose-xylose metabolic transition is of growing interest as a model to explore cellular adaption since these molecules are the main substrates resulting from the deconstruction of lignocellulosic biomass. Here, we investigated the role of the XylR transcription factor in the length of the lag phases when the bacterium Escherichia coli needs to adapt from glucose- to xylose-based growth. First, a variety of lag times were observed when different strains of E. coli were switched from glucose to xylose. These lag times were shown to be controlled by XylR availability in the cells with no further effect on the growth rate on xylose. XylR titration provoked long lag times demonstrated to result from phenotypic heterogeneity during the switch from glucose to xylose, with a subpopulation unable to resume exponential growth, whereas the other subpopulation grew exponentially on xylose. A stochastic model was then constructed based on the assumption that XylR availability influences the probability of individual cells to switch to xylose growth. The model was used to understand how XylR behaves as a molecular switch determining the bistability set-up. This work shows that the length of lag phases in E. coli is controllable and reinforces the role of stochastic mechanism in cellular adaptation, paving the way for new strategies for the better use of sustainable carbon sources in bioeconomy.IMPORTANCE For decades, it was thought that the lags observed when microorganisms switch from one substrate to another are inherent to the time required to adapt the molecular machinery to the new substrate. Here, the lag duration was found to be the time necessary for a subpopulation of adapted cells to emerge and become the main population. By identifying the molecular mechanism controlling the subpopulation emergence, we were able to extend or reduce the duration of the lags. This work is of special importance since it demonstrates the unexpected complexity of monoclonal populations during growth on mixed substrates and provides novel mechanistic insights with regard to bacterial cellular adaptation.
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M. Vorob’ev, Mikhail. "Tryptophan Fluorescence and Time-Lag Hydrolysis of Peptide Bonds during Degradation of β-Lactoglobulin by Trypsin." Catalysts 10, no. 12 (November 24, 2020): 1368. http://dx.doi.org/10.3390/catal10121368.
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The opening of protein globules and corresponding exposure of their internal peptide bonds, the so-called demasking effect, is required for successful hydrolysis of peptide bonds by proteases. Under the proteolytic action of trypsin on β-lactoglobulin (β-LG), the evolution of tryptophan fluorescence spectra showed that the demasking process consists of two stages with different demasking rate constants for each stage. It was found that the ratio of these constants depends on the concentration of trypsin and changes are approximately threefold when the concentration of trypsin changes in the range of 0.3–15 mg/L. Simulation of hydrolysis taking into account the demasking effect demonstrated how the apparent first-order rate constants obtained experimentally are related to the true hydrolysis rate constants and demasking parameters. The lag phase in the kinetic curves corresponding to the hydrolysis of various peptide bonds in β-LG was also analyzed. The increased lag times indicated sites that are hydrolyzed by a two-stage demasking mechanism.
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Coulie, B., J. Tack, B. Maes, B. Geypens, M. De Roo, and J. Janssens. "Sumatriptan, a selective 5-HT1 receptor agonist, induces a lag phase for gastric emptying of liquids in humans." American Journal of Physiology-Gastrointestinal and Liver Physiology 272, no. 4 (April 1, 1997): G902—G908. http://dx.doi.org/10.1152/ajpgi.1997.272.4.g902.
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Sumatriptan, a 5-hydroxytryptamine1 (5-HT1) receptor agonist at enteric neuronal 5-HT receptors, causes a relaxation of the gastric fundus and inhibition of antral contractile activity. The present study examined the effect of sumatriptan on gastric emptying of solids and liquids in humans. In eight healthy subjects the gastric emptying rate for liquids and solids was measured using the carbon-labeled glycine and octanoic acid breath test after subcutaneous administration of placebo or sumatriptan. Sumatriptan increased the gastric half-emptying time of liquids (P < 0.0005) and induced a prolonged lag phase for liquids (P < 0.0005) in all subjects. Sumatriptan increased gastric half-emptying time (P < 0.005) and the lag phase of solids (P < 0.05) in all subjects. In two healthy subjects gastric emptying of liquids and solids after subcutaneous administration of sumatriptan was studied by radioscintigraphy. Radioscintigraphy confirmed the delayed emptying and the prolonged lag phases after sumatriptan. In conclusion, sumatriptan delays gastric emptying of solids and liquids in healthy subjects. Moreover, sumatriptan induces a lag phase for liquids. The mechanism by which sumatriptan alters gastric emptying remains to be studied.
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Hale, Joanna, Jamie A. Ward, Francesco Buccheri, Dominic Oliver, and Antonia F. de C. Hamilton. "Are You on My Wavelength? Interpersonal Coordination in Dyadic Conversations." Journal of Nonverbal Behavior 44, no. 1 (October 15, 2019): 63–83. http://dx.doi.org/10.1007/s10919-019-00320-3.
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Abstract Conversation between two people involves subtle nonverbal coordination in addition to speech. However, the precise parameters and timing of this coordination remain unclear, which limits our ability to theorize about the neural and cognitive mechanisms of social coordination. In particular, it is unclear if conversation is dominated by synchronization (with no time lag), rapid and reactive mimicry (with lags under 1 s) or traditionally observed mimicry (with several seconds lag), each of which demands a different neural mechanism. Here we describe data from high-resolution motion capture of the head movements of pairs of participants (n = 31 dyads) engaged in structured conversations. In a pre-registered analysis pathway, we calculated the wavelet coherence of head motion within dyads as a measure of their nonverbal coordination and report two novel results. First, low-frequency coherence (0.2–1.1 Hz) is consistent with traditional observations of mimicry, and modeling shows this behavior is generated by a mechanism with a constant 600 ms lag between leader and follower. This is in line with rapid reactive (rather than predictive or memory-driven) models of mimicry behavior, and could be implemented in mirror neuron systems. Second, we find an unexpected pattern of lower-than-chance coherence between participants, or hypo-coherence, at high frequencies (2.6–6.5 Hz). Exploratory analyses show that this systematic decoupling is driven by fast nodding from the listening member of the dyad, and may be a newly identified social signal. These results provide a step towards the quantification of real-world human behavior in high resolution and provide new insights into the mechanisms of social coordination.
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Li, Qi Guang, Qiu Shi Han, Dong Hui Mu, Bao Ying Peng, and Guan Wei Jia. "Research on Error Sources Caused by Servo Feed in Cam Grinding." Advanced Materials Research 472-475 (February 2012): 2930–35. http://dx.doi.org/10.4028/www.scientific.net/amr.472-475.2930.
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With the development of auto industry, the cam quality requirements higher and higher. In order to illustrate the effect of servo lag upon cam Contour error, X-C servo axis Trajectory coordinates have been acquired in real-time with dual-channel mode during cam grinding. By comparing the Trajectory coordinates detected and the interpolation contour, the errors caused by servo feed lags were verified, and the mechanism that how axis feed acceleration impact on cam Contour errors was proposed. Based on data acquisition and product test, the error compensation method based on servo lag is proved reasonable.
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Oshchepkov, P. P., I. A. Zaev, S. V. Smirnov, and A. V. Bizhaev. "Study of Biodiesel Fuel with Palm Oil and Hydrogen Peroxide Additives." Agricultural Machinery and Technologies 13, no. 3 (July 22, 2019): 48–53. http://dx.doi.org/10.22314/2073-7599-2019-13-3-48-53.
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Palm oil is comparable to traditional diesel fuel in terms of calorifi c value, stoichiometric ratio, and cetane number. However, its increased kinematic viscosity and pour point make it diffi cult to use in pure form in diesel engines. (Research purpose) To study specifi c features of burning: diesel fuel with various additives of palm oil (biodiesel fuel); pure 100-percent palm oil; biodiesel fuel with various additives of palm oil and hydrogen peroxide, as well as to develop a method to control its combustion process. (Materials and methods) To determine the ignition time lag, the authors chose a method of kinetic modeling of self-ignition of biodiesel fuel in the air. The self-ignition process was simulated using the Chemical Workbench software package. An adiabatic calorimetric bomb model was used to perform calculations. To describe the process of self-ignition, a universal kinetic mechanism was used, which was verifi ed to calculate self-ignition of diesel and biodiesel fuel surrogates, as well as the formation of toxic substances and soot in the combustion processes. (Results and discussion) It is shown that adding palm oil to diesel fuel increases its ignition time lag, especially at low and medium temperatures of 750-950 kelvin. It was determined that with addition of 10 percent palm oil, the ignition time lag of biodiesel fuel is almost the same as that of diesel fuel no more than 5 percent. Increasing the amount of palm oil additive up to 30 percent and more signifi cantly increases the ignition time lag of the fuel. When using only palm oil as a fuel, the ignition time lag in the temperature range of 800-950 kelvin increases in two times. The study determined the optimal amount of hydrogen peroxide to be used for each composition of biodiesel fuel with various additives of palm oil. (Conclusions) It is shown that additives of hydrogen peroxide can infl uence the reactivity of biodiesel fuel and thereby regulate its ignition time lag.
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Schaper, Philipp, and Tobias Grundgeiger. "Commission errors with forced response lag." Quarterly Journal of Experimental Psychology 72, no. 10 (April 11, 2019): 2380–92. http://dx.doi.org/10.1177/1747021819840583.
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It is often necessary to retrieve intentions once a certain cue occurs in the environment. However, such prospective memory (PM) tasks can also be erroneously recalled even though they are no longer relevant and may result in commission errors. According to the dual mechanism account, commission errors occur because the intention is spontaneously retrieved, and there is a subsequent failure to suppress the associated action, resulting in erroneous instant execution. In three experiments, we tested whether failed response suppression is a prerequisite for commission errors. We set up a response lag condition in which participants had to delay their response to ongoing task trials for 1 s (Experiment 1) or 2 s (Experiments 2 and 3) and a pause condition in which the delay occurred between ongoing task trials. In both conditions, participants learned about a PM task and were then told that the PM task was cancelled. In addition, a control group with response lag executed the PM task and was subsequently told the task was finished. Later, all participants encountered several irrelevant PM cues. If failed response suppression is a prerequisite for commission errors, commission error rates should be non-existent in the response lag conditions, because participants had designated time to suppress the PM action. However, commission errors occurred at an equal rate in all lag and pause conditions. Due to this contradiction to the dual mechanism account, we suggest that the process for commission error occurrence should be reconsidered. Because commission errors appear not to be caused by failed response suppression, we discuss the idea that erroneous intentions might be formed when encountering the former PM cue and persist over delays between formation and execution.
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Ervin, C. Patrick, and Issa El-Hussain. "Hydroseismicity – A Viable Trigger Mechanism in the New Madrid Seismic Zone?" Seismological Research Letters 59, no. 4 (October 1, 1988): 285–88. http://dx.doi.org/10.1785/gssrl.59.4.285.
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Abstract A pressure wave, initiated by water loading and propagating downward through subsurface water contained in fractures, has been hypothesized as a mechanism for triggering earthquakes along pre-existing faults at depths up to 15–20 km. Such a triggering wave might evidence itself by a coincident wave of descending seismicity. In the New Madrid region, seismicity has been reported to correlate with river stage, but usually with a lag of one to several months. River stage data from New Madrid and earthquake data from the St. Louis University’s microseismic network were examined for evidence of a time-lag in seismic activity with depth during the interval from Jan. 1, 1978, to May 31, 1987. The earthquake data include only events for which computed depths were available. The earthquakes were sorted by focal depth into two subsets of 3 km and 4 km thick layers, respectively. Earthquake data, represented by both number of events and strain factor [energy release], and river stage data were averaged over monthly intervals. Cross correlations were computed between stage and each layer. In addition, the earthquake sequences for each layer were cross correlated with those of the next layer. No evidence for a seismicity wave was found.
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Schwarz, V., and I. M. Naomi Simpson. "Is salt reabsorption in the human sweat duct subject to control?" Clinical Science 68, no. 4 (April 1, 1985): 441–47. http://dx.doi.org/10.1042/cs0680441.
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1. There is a time lag between the beginning of sweat secretion and fully effective production of fluid of minimum salt content. It is suggested that changes in permeability to water or electrolytes have to be effected and may account for the time lag. 2. The composition of thermal and pilocarpine sweat indicates that pharmacological stimulation does not wholely reproduce the physiological mechanism: pilocarpine sweat contains more sodium and more cyclic AMP, irrespective of the secretory rate. 3. The sweat obtained from patients with cystic fibrosis has been compared with that from normal children: the concentrations of cyclic AMP and cyclic GMP are the same. Defective sodium reabsorption in the patients is therefore unlikely to be due to inadequate or excessive synthesis of these cyclic nucleotides.
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Xiaodan, Yu, Jia Hongjie, Wang Chengshan, and Jiang Yilang. "A Method to Determine Oscillation Emergence Bifurcation in Time-Delayed LTI System with Single Lag." Journal of Applied Mathematics 2014 (2014): 1–12. http://dx.doi.org/10.1155/2014/823937.
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One type of bifurcation named oscillation emergence bifurcation (OEB) found in time-delayed linear time invariant (abbr. LTI) systems is fully studied. The definition of OEB is initially put forward according to the eigenvalue variation. It is revealed that a real eigenvalue splits into a pair of conjugated complex eigenvalues when an OEB occurs, which means the number of the system eigenvalues will increase by one and a new oscillation mode will emerge. Next, a method to determine OEB bifurcation in the time-delayed LTI system with single lag is developed based on Lambert W function. A one-dimensional (1-dim) time-delayed system is firstly employed to explain the mechanism of OEB bifurcation. Then, methods to determine the OEB bifurcation in 1-dim, 2-dim, and high-dimension time-delayed LTI systems are derived. Finally, simulation results validate the correctness and effectiveness of the presented method. Since OEB bifurcation occurs with a new oscillation mode emerging, work of this paper is useful to explore the complex phenomena and the stability of time-delayed dynamic systems.
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Dharmawardena, Thavisha E., Francisca Kemper, Jan G. A. Wouterloot, Peter Scicluna, Jonathan P. Marshall, and Sofia H. J. Wallström. "The sub-mm variability of IRC+10216 and o Ceti." Monthly Notices of the Royal Astronomical Society 489, no. 3 (August 22, 2019): 3492–505. http://dx.doi.org/10.1093/mnras/stz2263.
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Abstract We present the sub-mm variability of two of the most well-studied AGB stars, IRC + 10216 and o Ceti. The data are obtained at $450$ and $850\,{\mu {\rm m}}$ as part of pointing calibration observations for the James Clerk Maxwell Telescope’s SCUBA-2 instrument over a span of 7 yr. The periods are derived using non-parametric methods, Gatspy Supersmoother and P4J, in order not to assume an underlying shape to the periodicity. These were compared to two Lomb–Scargle parametric methods. We find that for both sources and wavelengths the periods derived from all methods are consistent within 1σ. The $850\,{\mu {\rm m}}$ phase folded light curves of IRC + 10216 show a time lag of ∼540 d compared to its optical counterpart. We explore the origins of the sub-mm variability and the phase lag using radiative transfer models. Combining the modelling with findings in the literature, we find that the sub-mm emission and phase lag can be partially attributed to the dust formation or destruction cycle. A second, unknown mechanism must be invoked; we defer an investigation of the origin and nature of this mechanism to a future work.
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Omama, Tomoki, Makoto Uemura, Shiro Ikeda, and Mikio Morii. "Extracting common signal components from the X-ray and optical light curves of GX 339−4: New view for anti-correlation." Publications of the Astronomical Society of Japan 73, no. 3 (May 13, 2021): 716–27. http://dx.doi.org/10.1093/pasj/psab032.
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Abstract Simultaneous X-ray and optical observations of black hole X-ray binaries have shown that the light curves contain multiple correlated and anti-correlated variation components when the objects are in the hard state. In the case of the black hole X-ray binary GX 339−4, the cross correlation function (CCF) of the light curves suggests a positive correlation with an optical lag of 0.15 s and anti-correlations with an optical lag of 1 s and X-ray lag of 4 s. This indicates that the two light curves have some common signal components with different delays. In this study we extracted and reconstructed those signal components from the data for GX 339−4. The results confirmed that correlation and anti-correlation with the optical lag are two common components. However, we found that the reconstructed light curve for the anti-correlated component indicates a positively correlated variation with an X-ray lag of ∼+1 s. In addition, the CCF for this signal component shows anti-correlations not only with the optical lag, but also with the X-ray lag, which is consistent with the CCF for the data. Therefore, our results suggest that the combination of the two positively correlated components, that is, the X-ray preceding signal with the 0.15 s optical lag and the optical preceding signal with the 1 s X-ray lag, can make the observed CCF without anti-correlated signals. The optical preceding signal may be caused by synchrotron emission in a magnetically dominated accretion flow or in a jet, while further study is required to understand the mechanism of the X-ray time lag.
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Umemoto, Ayaka, Hisashi Yagi, Masatomo So, and Yuji Goto. "High-throughput Analysis of Ultrasonication-forced Amyloid Fibrillation Reveals the Mechanism Underlying the Large Fluctuation in the Lag Time." Journal of Biological Chemistry 289, no. 39 (August 12, 2014): 27290–99. http://dx.doi.org/10.1074/jbc.m114.569814.
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Zhao, Chengguo, Meng Li, Jun Wang, and Shujian Ma. "The mechanism of credit risk contagion among internet P2P lending platforms based on a SEIR model with time-lag." Research in International Business and Finance 57 (October 2021): 101407. http://dx.doi.org/10.1016/j.ribaf.2021.101407.
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Lei, Zhang, Gu Jian-ping, Wei Shi-qing, Zhou Ze-yang, Zhang Chao, and Yu Yongxiong. "Mechanism of acid tolerance in a rhizobium strain isolated from Pueraria lobata (Willd.) Ohwi." Canadian Journal of Microbiology 57, no. 6 (June 2011): 514–24. http://dx.doi.org/10.1139/w11-036.
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The Rhizobium sp. strain PR389 was isolated from the root nodules of Pueraria lobata (Willd.) Ohwi, which grows in acidic (pH 4.6) yellow soil of the Jinyun Mountains of Beibei, Chongqing, China. While rhizobia generally have a pH range of 6.5–7.5 for optimum growth, strain PR389 grew in a liquid yeast extract – mannitol agar medium at pH 4.6, as well as in a pH 4.1 soil suspension, suggesting acid tolerance in this specific strain of rhizobium . However, at pH 4.6, the lag phase before vigorous growth was 40 h compared with 4 h under neutral conditions (pH 7.0). For PR389, the generation time after the lag phase remained the same at different pH levels despite the different durations of the lag phase. Except in the pH 4.4 treatment, the pH of the culturing media increased from 4.6, 4.8, 5.0, and 5.5 to neutral and slightly alkaline after 70 h of culture. Chloramphenicol was added to determine if protein production was involved in the increasing pH process. Chloramphenicol significantly inhibited PR389 growth under acid stress but had little effect under neutral conditions. Proton flux measured during a short acid shock (pH 3.8) revealed that this strain has an intrinsic ability to prevent H+ from entering cells when compared with acid-sensitive rhizobia. We propose that the mechanism for acid tolerance in PR389 involves both intracellular and extracellular processes. When the extracellular pH is lower than pH 4.4, the cell membrane blocks hydrogen from entering the cell. When the pH exceeds 4.4, the rhizobium strain has the ability to raise the extracellular pH, thereby, potentially decreasing the toxicity of aluminum in acid soil.
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Pan, Dingyi, Jian Deng, Xueming Shao, and Zubin Liu. "On the Propulsive Performance of Tandem Flapping Wings with a Modified Immersed Boundary Method." International Journal of Computational Methods 13, no. 05 (August 31, 2016): 1650025. http://dx.doi.org/10.1142/s0219876216500250.
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The modified immersed boundary method is introduced and applied to study the propulsive mechanism of a tandem flapping wings system. The effects of tandem wings distance and phase lag between the two flapping wings are investigated. Thrust force of the upstream wing is nearly constant and close to the magnitude of single flapping wing system. Thrust force of second wing is influenced by the distance and phase lag. With specific parameters, the second wing can obtain a maximum thrust which is larger than the one of first wing. The flow structures of the wake flow are classified into three different formations, and they are correlated to the trends of thrust force. The effects of distance and phase lag are coupled other than isolated. It is possible to lower down the power consumption of this tandem flapping wings system and enhance the total thrust force of the system at the same time.
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Li, Ziyan, Donglin Huang, and Louis M. McDonald. "Heterogeneous selenite reduction by zero valent iron steel wool." Water Science and Technology 75, no. 4 (December 9, 2016): 908–15. http://dx.doi.org/10.2166/wst.2016.574.
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Mine drainage from the low-sulfur surface coal mines in southern West Virginia, USA, is circumneutral (pH > 6) but contains elevated selenium (Se) concentrations. Removal of selenite ions from aqueous solutions under anoxic condition at pH 6–8.5 by zero valent iron steel wool (ZVI-SW) was investigated in bench-scale kinetic experiments using wet chemical, microscopic and spectroscopic techniques (X-ray photoelectron spectroscopy). ZVI-SW could effectively and efficiently remove SeIV from solution with pH 6–8.5. A two-step removal mechanism was identified for SeIV reduction by ZVI-SW. The proposed mechanism was electrochemical reduction of SeIV by Fe0 in an initial lag stage, followed by a faster heterogeneous reduction, mediated by an FeII-bearing phase (hydroxide or green rust). Solution pH was a critical factor for the kinetic rate in the lag stage (0.33 h−1 for pH > 8 and 0.10 h−1 for pH 6–8). The length of lag stage was 20–30 min as determined by the time for dissolved FeII concentration to reach 0.30 ± 0.04 mg L−1 which was critical for induction of the faster stage. About 65% of the initial SeIV was reduced to Se0, the primary reductive product in both stages.
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Thapa, Prakash, and Seong Jeong. "Effects of Formulation and Process Variables on Gastroretentive Floating Tablets with A High-Dose Soluble Drug and Experimental Design Approach." Pharmaceutics 10, no. 3 (September 17, 2018): 161. http://dx.doi.org/10.3390/pharmaceutics10030161.
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To develop sustained release gastro-retentive effervescent floating tablets (EFT), a quality-based experimental design approach was utilized during the composing of a hydrophilic matrix loaded with a high amount of a highly water-soluble model drug, metformin HCl. Effects of the amount of polyethylene oxide WSR 303 (PEO), sodium bicarbonate, and tablet compression force were used as independent variables. Various times required to release the drug, tablet tensile strength, floating lag time, tablet ejection force, and tablet porosity, were selected as the responses. Polymer screening showed that PEO had the highest gel strength among the various tested polymers. Sodium bicarbonate had the most significant effect on the release rate and floating lag time by retarding the rate from the hydrophilic matrices, whilst tablet compression force and PEO exerted the greatest influence on tablet properties (p < 0.0001). The design space was built in accordance with the drug release profiles, tensile strength, and floating lag time, following failure probability analysis using Monte Carlo simulations. The kinetic modeling revealed that the release mechanism was best described by the Korsmeyer-Peppas model. Overall, the current study provided a perspective on the systematic approach of gastro-retentive EFT, loaded with highly water-soluble drugs by applying quality by design concepts.
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Jiang, Yun-Guo, Ke-Xin Liu, Lang Shao, and Huai-Zhen Li. "Interpreting the spectral lags of single-pulsed gamma-ray bursts via the photosphere in the jet model." Monthly Notices of the Royal Astronomical Society: Letters 505, no. 1 (May 10, 2021): L26—L30. http://dx.doi.org/10.1093/mnrasl/slab045.
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ABSTRACT The prompt emission of gamma-ray bursts (GRBs) is a long-standing problem. The spectral-lag phenomenon can provide us with some clues about the emission mechanism. By analogy with the spectral lag of blazars at radio frequencies, we propose using the photosphere in the jet model to interpret the spectral lag of GRBs. Assuming a canonical jet and respecting the scaling laws of both the magnetic field and the number density of radiative particles, the radius of the photosphere and the magnetic field can be predicted. Five long bursts with known redshifts are studied. The prompt emitting regions of these bursts are located at about one or several astronomical units from the jet base. Without strictly constrained parameters, the magnetic fields at the photosphere radius are not well constrained. Taking the median values, the magnetic field is distributed in the range of 104∼107 G, which has no conflicts with the constraints obtained from the synchrotron cooling time.
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Miyamoto, Tadayoshi, Hidehiro Nakahara, Shinya Ueda, Kou Manabe, Eriko Kawai, Masashi Inagaki, Toru Kawada, and Masaru Sugimachi. "Periodic Breathing in Heart Failure Explained by Dynamic and Static Properties of Respiratory Control." Clinical Medicine Insights: Cardiology 9s1 (January 2015): CMC.S18761. http://dx.doi.org/10.4137/cmc.s18761.
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Objective The respiratory operating point is determined by the interplay between the controller and plant subsystem elements within the respiratory chemoreflex feedback system. This study aimed to establish the methodological basis for quantitative analysis of the open-loop dynamic properties of the human respiratory control system and to apply the results to explore detailed mechanisms of the regulation of respiration and the possible mechanism of periodic breathing in chronic heart failure. Methods and Results In healthy volunteers, we measured arterial CO2 partial pressure (PaCO2) and minute ventilation (V̇E) to estimate the dynamic properties of the controller (PaCO2→V̇E relation) and plant (V̇E→PaCO2 relation). The dynamic properties of the controller and plant approximated first- and second-order exponential models, respectively, and were described using parameters including gain, time constant, and lag time. We then used the open-loop transfer functions to simulate the closed-loop respiratory response to an exogenous disturbance, while manipulating the parameter values to deviate from normal values but within physiological ranges. By increasing both the product of gains of the two subsystem elements (total loop gain) and the lag time, the condition of system oscillation (onset of periodic breathing) was satisfied. Conclusion When abnormality occurs in a part of the respiratory chemoreflex system, instability of the control system is amplified and may result in the manifestation of respiratory abnormalities such as periodic breathing.
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Li, Xue Chen, and Peng Ying Jia. "A Novel Optical System for Investigation on the Characteristics of Light Emission from Long Plasma Column." Applied Mechanics and Materials 220-223 (November 2012): 2047–51. http://dx.doi.org/10.4028/www.scientific.net/amm.220-223.2047.
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Although intensified charge coupled device (ICCD) is conventionally used to investigate the breakdown mechanism in gas discharge. ICCD can not be used to study the long plasma column because it is hard to be imaged. For solving this problem, a novel optical system is proposed which consists of several elements. Each element is composed of one collimator and a photomultiplier tube. Using this system, spatial resolved emission signal can be obtained. Results show that the light emission signal from each area shows a pulse with a width of about 3μs. It is interesting that the time lag in each half cycle increases with the increase of distance away from the dielectric barrier discharge (DBD). This phenomenon implies that the plasma bullet always leaves DBD at the rising edge of the applied voltage. The time lag versus the distance from DBD is used to calculate the propagation velocity of the discharge.
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Liu, Yunzhe, Marcelo G. Mattar, Timothy E. J. Behrens, Nathaniel D. Daw, and Raymond J. Dolan. "Experience replay is associated with efficient nonlocal learning." Science 372, no. 6544 (May 20, 2021): eabf1357. http://dx.doi.org/10.1126/science.abf1357.
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To make effective decisions, people need to consider the relationship between actions and outcomes. These are often separated by time and space. The neural mechanisms by which disjoint actions and outcomes are linked remain unknown. One promising hypothesis involves neural replay of nonlocal experience. Using a task that segregates direct from indirect value learning, combined with magnetoencephalography, we examined the role of neural replay in human nonlocal learning. After receipt of a reward, we found significant backward replay of nonlocal experience, with a 160-millisecond state-to-state time lag, which was linked to efficient learning of action values. Backward replay and behavioral evidence of nonlocal learning were more pronounced for experiences of greater benefit for future behavior. These findings support nonlocal replay as a neural mechanism for solving complex credit assignment problems during learning.
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Singh, Maninder Pal, Manish Kumar, and Ravi Shankar. "Development and Optimization of Methscopolamine Bromide Gastroretentive Floating Tablets Using 32 Factorial Design." Drug Research 70, no. 12 (September 29, 2020): 576–82. http://dx.doi.org/10.1055/a-1249-8186.
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Abstract Purpose The aim of this study was to formulate methscopolamine floating drug delivery system to increase its gastro retention for further enhancement of absorption and overall bioavailability. Method Direct compression method was used to formulate floating drug delivery system of methscopolamine bromide. Different amount of HPMC, PVP K25, and MCC were used for preparation of tablets. Result The prepared tablets were evaluated for thickness, hardness, weight variation, floating lag time, swelling index and in-vitro drug release. All the formulations showed less than 10% of weight variation. The hardness and thickness of all the formulations were within the range of 3.7−4.2 kg/cm2 and 3.63−3.83 mm respectively. Floating lag time for all the formulations was reported in seconds. The degree of swelling was reported in range of 82.10−85.83%. In vitro release was carried out for 24 h. The maximum release was shown by F1 (93.947%) while the minimum release was observed for F4 (90.420%). The best formulation was optimized on the basis of percentage cumulative drug release, floating lag time and swelling index. F1 found to be the best formulation. Further on analyzing the drug release mechanism, F1 found to exhibit korsmeyer peppas model of drug release. Conclusion Floating gastroretentive tablet of methscopolamine bromide was successfully developed using direct compression method with potential to enhance the drug absorption and effective treatment of peptic ulcer.
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Yan, Sen, Jing Qi Zhang, and Wei Zhi Diao. "Ball Mill Automatic Control System Design Based on Fuzzy PID Control." Applied Mechanics and Materials 441 (December 2013): 825–28. http://dx.doi.org/10.4028/www.scientific.net/amm.441.825.
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For ball mill grinding process random interference by many factors, processes complex mechanism, there is a big inertia and the lag, the fuzzy control theory is introduced into the mill control system, has strong robustness, can effectively overcome the mill main motor power nonlinear, time-varying factors such as interference. System is reliable, adjust speed, anti-interference ability, can better achieve constant power automatic control of the ball mill, with good application value.
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Munagala Gayatri Ramya and Kothapalli Bannoth Chandra Sekhar. "Preparation and evaluation of matrix type gastro retentive floating atenolol tablets using sintering technique." International Journal of Research in Pharmaceutical Sciences 11, no. 2 (April 16, 2020): 1920–26. http://dx.doi.org/10.26452/ijrps.v11i2.2109.
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The aim of this investigation was to design and assess the gastric floating tablets of Atenolol using thermal sintering and investigate the effect of sintering on PEO polymer. Atenolol is an Antihypertensive with only 50 percent bioavailability due to poor absorption in lower GI tract. Gastro retentive Floating tablets were prepared to enhance the gastric retention time, to prolong the drug release. PEO which was selected as sintered polymer. Tablets were prepared by direct compression method .Formulated tablets were exposed to different temperatures (400C, 500C and 600C) at various time intervals( 1h ,2h ,3h and4h) in a hot air oven .Post compression parameters were evaluated like weight variation, hardness, friability, floating lag time and total floating time. The result of the investigation indicates sintering influenced the floating time and dissolution properties. Weight variation, friability and content uniformity values were within limits. Sintering time and temperature contributes to effectiveness of polymers in extending drug release. Reduction in floating lag time and increase in total floating time as well as release of drug was delayed. All sintered formulation have no interaction was found in FTIR, DSC studies. All sintered tablets followed zero order with nonfickian diffusion mechanism. This study helps the use of thermal sintering in preparation of floating tablets.
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Yu, Xiaobao, Zhongfu Tan, Yuxie Zhang, Daoxin Peng, and Hui Xia. "The Feedback Mechanism of Carbon Emission Reduction in Power Industry of Delayed Systems." Mathematical Problems in Engineering 2017 (2017): 1–14. http://dx.doi.org/10.1155/2017/4163729.
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Carbon emissions of power industry in China have accounted for more than half of the total emissions. How to decrease them is important for realizing carbon emission reduction. This paper proposes a carbon market feedback mechanism to power market, comprehensively considering the influence of generation structure, carbon intension, and technological progress on carbon emission reduction in power industry, and builds a potential model based on dynamic system. Operation system results show that the increasing trend of carbon emission can be controlled effectively but always with a lag. At the same time, sensitivity analysis results show that carbon emission reduction can be better realized by adjusting power structure and improving technological level; the former can reduce 32% and the latter can reduce 60% at most.
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Karpouzas, Konstantinos, Mariano Méndez, Evandro M. Ribeiro, Diego Altamirano, Omer Blaes, and Federico García. "The Comptonizing medium of the neutron star in 4U 1636 − 53 through its lower kilohertz quasi-periodic oscillations." Monthly Notices of the Royal Astronomical Society 492, no. 1 (December 16, 2019): 1399–415. http://dx.doi.org/10.1093/mnras/stz3502.
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ABSTRACT Inverse Compton scattering dominates the high-energy part of the spectra of neutron star (NS) low-mass X-ray binaries (LMXBs). It has been proposed that inverse Compton scattering also drives the radiative properties of kilohertz quasi-periodic oscillations (kHz QPOs). In this work, we construct a model that predicts the energy dependence of the rms amplitude and time lag of the kHz QPOs. Using this model, we fit the rms amplitude and time lag energy spectra of the lower kHz QPO in the NS LMXB 4U 1636 − 53 over 11 frequency intervals of the QPO and report three important findings: (i) A medium that extends 1–8 km above the NS surface is required to fit the data; this medium can be sustained by the balance between gravity and radiation pressure, without forcing any equilibrium condition. (ii) We predict a time delay between the oscillating NS temperature, due to feedback, and the oscillating electron temperature of the medium, which, with the help of phase resolved spectroscopy, can be used as a probe of the geometry and the feedback mechanism. (iii) We show that the observed variability as a function of QPO frequency is mainly driven by the oscillating electron temperature of the medium. This provides strong evidence that the Comptonizing medium in LMXBs significantly affects, if not completely drives, the radiative properties of the lower kHz QPOs regardless of the nature of the dynamical mechanism that produces the QPO frequencies.
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Li, Fan, Zhi Min Song, and Xing Han. "Research on the Association Mechanism between China's Textile Industry and Macroeconomic — Based on VAR Model." Advanced Materials Research 332-334 (September 2011): 2050–53. http://dx.doi.org/10.4028/www.scientific.net/amr.332-334.2050.
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This paper studies the relationship between the development of textile industry and the macroeconomic growth. By establishing the VAR model and co-integration test, the paper systematically describes the dependency between them. It also applies the method of impulse response function and variance decomposition to analyze their dynamic correlations. The result shows that there exists a long-term relationship between the textile industry and macroeconomic in China. But the relevance between them has something alike as well as something different through the analysis of impulse response function and variance decomposition. The good functioning of macroeconomic creats favourable conditions for the development of the textile industry. However, the influence on the textile industry of macroeconomic has a time-lag effect.
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Georg, H., C. W. Wharton, and F. Siebert. "Temperature Induced Protein Unfolding and Folding of RNase a Studied by Time-Resolved Infrared Spectroscopy." Laser Chemistry 19, no. 1-4 (January 1, 1999): 233–35. http://dx.doi.org/10.1155/1999/28202.
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When a protein finds its native three-dimensional structure from the unstructured amino-acid chain various processes spanning a large time range are relevant. To understand the mechanism of protein folding one needs to cover the entire folding/ refolding (U↔N) reaction on a structural level. In the case of RNase A, the main structural changes occur in the ms time range, that can be monitored with rapid-scan- FTIR spectroscopy combined with rapid mixing techniques. To induce unfolding we inject aqueous protein solution into a hot IR cuvette and record the time course of the spectral changes. A lag phase is found when the unfolding conditions are relatively weak, suggesting an unfolding intermediate.
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Yuan, Manman, Weiping Wang, Xiong Luo, Lixiang Li, Jürgen Kurths, and Xiao Wang. "Exponential lag function projective synchronization of memristor-based multidirectional associative memory neural networks via hybrid control." Modern Physics Letters B 32, no. 09 (March 30, 2018): 1850116. http://dx.doi.org/10.1142/s0217984918501166.
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This paper is concerned with the exponential lag function projective synchronization of memristive multidirectional associative memory neural networks (MMAMNNs). First, we propose a new model of MMAMNNs with mixed time-varying delays. In the proposed approach, the mixed delays include time-varying discrete delays and distributed time delays. Second, we design two kinds of hybrid controllers. Traditional control methods lack the capability of reflecting variable synaptic weights. In this paper, the controllers are carefully designed to confirm the process of different types of synchronization in the MMAMNNs. Third, sufficient criteria guaranteeing the synchronization of system are derived based on the derive-response concept. Finally, the effectiveness of the proposed mechanism is validated with numerical experiments.
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Bulitta, Jürgen B., Neang S. Ly, Cornelia B. Landersdorfer, Nicholin A. Wanigaratne, Tony Velkov, Rajbharan Yadav, Antonio Oliver, et al. "Two Mechanisms of Killing of Pseudomonas aeruginosa by Tobramycin Assessed at Multiple Inocula via Mechanism-Based Modeling." Antimicrobial Agents and Chemotherapy 59, no. 4 (February 2, 2015): 2315–27. http://dx.doi.org/10.1128/aac.04099-14.
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ABSTRACTBacterial resistance is among the most serious threats to human health globally, and many bacterial isolates have emerged that are resistant to all antibiotics in monotherapy. Aminoglycosides are often used in combination therapies against severe infections by multidrug-resistant bacteria. However, models quantifying different antibacterial effects of aminoglycosides are lacking. While the mode of aminoglycoside action on protein synthesis has often been studied, their disruptive action on the outer membrane of Gram-negative bacteria remains poorly characterized. Here, we developed a novel quantitative model for these two mechanisms of aminoglycoside action, phenotypic tolerance at high bacterial densities, and adaptive bacterial resistance in response to an aminoglycoside (tobramycin) against threePseudomonas aeruginosastrains. At low-intermediate tobramycin concentrations (<4 mg/liter), bacterial killing due to the effect on protein synthesis was most important, whereas disruption of the outer membrane was the predominant killing mechanism at higher tobramycin concentrations (≥8 mg/liter). The extent of killing was comparable across all inocula; however, the rate of bacterial killing and growth was substantially lower at the 108.9CFU/ml inoculum than that at the lower inocula. At 1 to 4 mg/liter tobramycin for strain PAO1-RH, there was a 0.5- to 6-h lag time of killing that was modeled via the time to synthesize hypothetical lethal protein(s). Disruption of the outer bacterial membrane by tobramycin may be critical to enhance the target site penetration of antibiotics used in synergistic combinations with aminoglycosides and thereby combat multidrug-resistant bacteria. The two mechanisms of aminoglycoside action and the new quantitative model hold great promise to rationally design novel, synergistic aminoglycoside combination dosage regimens.
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Sun, Hong Xing, Chuang Gao, and Xin Yan. "Design and Research of Energy Saving Control System for Heating Network." Advanced Materials Research 591-593 (November 2012): 1405–9. http://dx.doi.org/10.4028/www.scientific.net/amr.591-593.1405.
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In the central heating system, because the controlled object has the characteristics of time-varying, nonlinear, strong coupling and big lag. The traditional single loop model and the conventional PID control algorithm are difficult to react the mechanism and meet the control requirements. Therefore a model of multiplex heating network is established. By comparing the single neuron PID control algorithm with the traditional PID control algorithm, the results show that the single neuron PID control algorithm has a better control effect.
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Ebrahimzadeh, P., M. Schiek, P. Jaros, T. Kapitaniak, S. van Waasen, and Y. Maistrenko. "Minimal chimera states in phase-lag coupled mechanical oscillators." European Physical Journal Special Topics 229, no. 12-13 (September 2020): 2205–14. http://dx.doi.org/10.1140/epjst/e2020-900270-4.
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Abstract We obtain experimental chimera states in the minimal network of three identical mechanical oscillators (metronomes), by introducing phase-lagged all-to-all coupling. For this, we have developed a real-time model-in-the-loop coupling mechanism that allows for flexible and online change of coupling topology, strength and phase-lag. The chimera states manifest themselves as a mismatch of average frequency between two synchronous and one desynchronized oscillator. We find this kind of striking “chimeric” behavior is robust in a wide parameter region. At other parameters, however, chimera state can lose stability and the system behavior manifests itself as a heteroclinic switching between three saddle-type chimeras. Our experimental observations are in a qualitative agreement with the model simulation.
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Valero, E., and F. García-Carmona. "pH-induced kinetic co-operativity of a thylakoid-bound polyphenol oxidase." Biochemical Journal 286, no. 2 (September 1, 1992): 623–26. http://dx.doi.org/10.1042/bj2860623.
Full textAbstract:
A study of the catecholase activity of a latent plant polyphenol oxidase, extracted and purified from the chloroplast membranes of grapes (Vitis vinifera cv. Airen), revealed for the first time a lag phase above pH 5.0, whereas a steady-state rate was reached immediately when pH values were lower, thus suggesting the hysteretic nature of the enzyme. During steady state, the enzyme showed negative co-operativity concomitant with the presence of the lag period, and followed classical Michaelis-Menten kinetics under more acid pH conditions. Statistical analysis of these data showed a minimal value for the extreme Hill coefficient of 0.54 at pH 6.0. This kinetic behaviour of polyphenol oxidase has been interpreted in terms of the pH-induced ‘slow’ transition mechanism reported by Ricard, Noat & Nari [(1984) Eur. J. Biochem. 145, 311-317] in which the conformational change does not affect the active site of the enzyme.