Journal articles: 'Inertia stack'

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Zhang, Zhiming, Jun Zhang, Yapeng Shang, and Tong Zhang. "Study on the Optimal Cross-Sectional Shapes of the PEMFC Endplates by Using a Moment of Inertia and 3D FEM Models." Sustainability 14, no. 19 (October 10, 2022): 12939. http://dx.doi.org/10.3390/su141912939.

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The deflection of the endplate under the clamping force has a vital effect on fuel cell performance. An optimal cross-sectional shape with a high moment of inertia of the endplate is significant to maximize the bending stiffness of the fuel cell stack. Five cross-sectional shapes (rectangular, round, parabolic, rectangular + round, and rectangular + parabolic) of the typical endplates are proposed. An analytical study on the moments of inertia of the endplates is introduced and analyzed. The maximum moments of inertia of the cross-sections are obtained and displayed in a matrix in thickness and length. The statistical results show that the “rectangular + parabolic” cross-section has the advantage of wide dimensional size while maintaining a high moment of inertia. Finally, the analytical studies are validated by a finite element method (FEM) and the corresponding trends are highly agreed upon. The maximum moment of inertia of the parabolic endplate is 85.71% higher than the rectangular endplate with a thickness of 80 mm, and the corresponding contact pressure variance is 6.15% less than the rectangular endplate. The presented analytical study is significant and effective to optimize the cross-sectional shape of the endplate and provide an endplate design direction for a large fuel cell stack.

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Goldin, Rebecca, Megumi Harada, David Johannsen, and Derek Krepski. "Inertia groups of a toric Deligne-Mumford stack, fake weighted projective stacks, and labeled sheared simplices." Rocky Mountain Journal of Mathematics 46, no. 2 (April 2016): 481–517. http://dx.doi.org/10.1216/rmj-2016-46-2-481.

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Chen, Tao, and Da Wei Zhang. "Development of Vibration Excitation and Control System for High Frequency Application." Applied Mechanics and Materials 246-247 (December 2012): 1283–88. http://dx.doi.org/10.4028/www.scientific.net/amm.246-247.1283.

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A complete system of vibration excitation with force feedback control for piezoelectric inertial exciter is presented. The vibration exciter is constructed and its dynamic model is established composed by piezoelectric stack, inertial mass and pretension institutions based on principle of inertia and reaction. The control system takes software program as the core part. The workflow of the digital step sine sweep control software for exciting force limit is recounted. Variety techniques are utilized to ensure real time and stability in the control process, including synchronization output and acquisition, extracting single tone information from waveform, model reference adaptive scaling control for amplitude of the output waveform. Some tests on a micro driving platform with high stiffness are carried out to verify the actual performance of the system. The results show that the piezoelectric inertial exciter and control system designed are very suitable for step sine sweep vibration excitation and exciting force control in high frequency range.

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Nandi, A., and S. Neogy. "Performance Analysis of a Hybrid One-Sided Magnetic Exciter Mounted on a Piezoelectric Stack." Shock and Vibration 17, no. 2 (2010): 205–15. http://dx.doi.org/10.1155/2010/805823.

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The present work proposes a non-contact hybrid exciter especially useful for harmonic excitation of lightly damped structures/rotors. In the proposed exciter an electromagnet is placed on a piezoelectric stack and the extension of the piezoelectric stack is made almost equal to the displacement of the structure using a simple tracking control. This largely eliminates stiffness coupling between the structure/rotor and the exciter and non-linearity in the excitation force due to the vibration of the structure/rotor. The stiffness and inertia of the piezoelectric stack is considered in the analysis. A SIMULINK model of the combined structure and the exciter is developed for a full time-domain simulation of the excitation system.

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Alrijadjis, Alrijadjis. "A MODIFIED PARTICLE SWARM OPTIMIZATION WITH RANDOM ACTIVATION FOR INCREASING EXPLORATION." Kursor 8, no. 1 (December 13, 2016): 33. http://dx.doi.org/10.28961/kursor.v8i1.72.

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Particle Swarm Optimization (PSO) is a popular optimization technique which is inspired by the social behavior of birds flocking or fishes schooling for finding food. It is a new metaheuristic search algorithm developed by Eberhart and Kennedy in 1995. However, the standard PSO has a shortcoming, i.e., premature convergence and easy to get stack or fall into local optimum. Inertia weight is an important parameter in PSO, which significantly affect the performance of PSO. There are many variations of inertia weight strategies have been proposed in order to overcome the shortcoming. In this paper, a new modified PSO with random activation to increase exploration ability, help trapped particles for jumping-out from local optimum and avoid premature convergence is proposed. In the proposed method, an inertia weight is decreased linearly until half of iteration, and then a random number for an inertia weight is applied until the end of iteration. To emphasis the role of this new inertia weight adjustment, the modified PSO paradigm is named Modified PSO with random activation (MPSO-RA). The experiments with three famous benchmark functions show that the accuracy and success rate of the proposed MPSO-RA increase of 43.23% and 32.95% compared with the standard PSO.

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KAUFMANN, RALPH M., and DAVID PHAM. "THE DRINFEL'D DOUBLE AND TWISTING IN STRINGY ORBIFOLD THEORY." International Journal of Mathematics 20, no. 05 (May 2009): 623–57. http://dx.doi.org/10.1142/s0129167x09005431.

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This paper exposes the fundamental role that the Drinfel'd double D(k[G]) of the group ring of a finite group G and its twists Dβ(k[G]), β ∈ Z3(G,k*) as defined by Dijkgraaf–Pasquier–Roche play in stringy orbifold theories and their twistings. The results pertain to three different aspects of the theory. First, we show that G-Frobenius algebras arising in global orbifold cohomology or K-theory are most naturally defined as elements in the braided category of D(k[G])-modules. Secondly, we obtain a geometric realization of the Drinfel'd double as the global orbifold K-theory of global quotient given by the inertia variety of a point with a G action on the one hand and more stunningly a geometric realization of its representation ring in the braided category sense as the full K-theory of the stack [pt/G]. Finally, we show how one can use the co-cycles β above to twist the global orbifold K-theory of the inertia of a global quotient and more importantly, the stacky K-theory of a global quotient [X/G]. This corresponds to twistings with a special type of two-gerbe.

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Li, Jin, Chang Jun Liu, Xin Wen Xiong, Yi Fan Liu, and Wen Jun Zhang. "A computationally efficient model to capture the inertia of the piezoelectric stack in impact drive mechanism in the case of the in-pipe inspection application." Mechanical Sciences 7, no. 1 (March 17, 2016): 79–84. http://dx.doi.org/10.5194/ms-7-79-2016.

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Abstract. This paper presents a new model for the piezoelectric actuator (PA) in the context of in the impact drive mechanism (IDM) for the in-pipe inspection application. The feature of the model is capturing the inertia of PA stack in a distributed manner as opposed to the lumped manner in literature. The benefit arising from this feature is a balanced trade-off between computational efficiency and model accuracy. The study presented in this paper included both theoretical development (i.e. the model of the piezoelectric actuator and the model of the entire IDM which includes the actuator) and experimental verification of the model. The study has shown that (1) the inertia of the PA in such a robot will significantly affect the accuracy of the entire model of IDM and (2) the simulation of the dynamic behavior with the proposed model is sufficiently accurate by comparing with the experiment. It is thus recommended that the inertia of the PA be considered in the entire model of the IDM robot. The model is an analytical type, which has a high potential to be used for the model-based control of the IDM robot and optimization of its design for a much improved performance of the IDM system.

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Changbin, Guan, and Jiao Zongxia. "A piezoelectric direct-drive servo valve with a novel multi-body contacting spool-driving mechanism: Design, modelling and experiment." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 228, no. 1 (March 26, 2013): 169–85. http://dx.doi.org/10.1177/0954406213483072.

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Stack-type piezoelectric actuators, which usually consist of several ceramic layers connected in series, are widely used in piezoelectric direct-drive servo valves (PDDSV). However, poor pulling force capacity of this kind of actuators affects the performances of the direct-drive servo valves. This article presents a new type of PDDSV, whose spool-driving mechanism is composed of a set of independent parts that are not fixed together but are in contact with each other. This multi-body contacting spool-driving mechanism provides bidirectional movement of the spool by a preloaded stack-type piezoelectric actuator and a driving disc spring. This prevents the stack-type piezoelectric actuator from bearing the pulling force due to the inertia and friction of the spool. Design of the proposed servo valve is illustrated in detail and its characteristics are also predicted. Based on a nonlinear dynamic model of the multi-body contacting spool-driving mechanism, a comprehensive dynamic simulation model of the proposed PDDSV is established. Static and dynamic characteristics of the proposed PDDSV have been studied experimentally and good agreements between experimental and simulation results are observed. The dynamic performances of the proposed PDDSV are compared with the existing piezoelectric servo valves, which demonstrate that the proposed PDDSV has satisfactory dynamic characteristics for high-frequency applications.

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Zhong, Wei, Jian Peng Yang, Bao An Pei, and Wei Zhang. "Study on the Shaft Height of Natural Ventilation Using Smoking Shaft in Urban Tunnel." Applied Mechanics and Materials 90-93 (September 2011): 2297–300. http://dx.doi.org/10.4028/www.scientific.net/amm.90-93.2297.

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The characteristics of smoke flow in natural ventilation shaft are studied in this paper, Using the computational fluid dynamics software FDS5.0 to build a 3D model of an urban tunnel with a smoking shaft, Large Eddy Simulation model was used to obtain the structure of flow field and the mass flow rate of natural ventilation at different shaft height, The results show that when the shaft height is low, the driving force of exhaust is weak and the exhaust capacity reduces rapidly, the flow state in shaft is controlled by horizontal inertia force; when the shaft height increase to a critical height, the exhaust effect enhance significantly, the flow state in shaft will change to stack effect control.

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Wang, Hong Cheng, Li Jun Yang, Jia Liu, and Zhen Dong Dai. "Controlled Encapsulation of Micron-Sized Beads in a Droplet Based on Pulse Inertia Force Driving of Micro-Fluids." Key Engineering Materials 645-646 (May 2015): 1009–15. http://dx.doi.org/10.4028/www.scientific.net/kem.645-646.1009.

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Loading drops with discrete objects, such as particles and cells, is often necessary when performing chemical and biological assays in microfluidic devices. The vast majority of reported encapsulating methods of particles into monodisperse picolitre droplets are based on micro-fluidic chip using the standard soft lithography technique are necessary. This paper presents a new approach, not based on micro-fluidic chip, for encapsulating particles into droplets actuated by microfluidic pulse inertia force. The polystyrene bead suspension can be ejected out of a tapered glass capillary in mineral oil drop by drop actuated by an enough pulse inertia force which is produced by a hollow PZT stack. The polystyrene beads will be randomly encapsulated in monodisperse picolitre droplets. The tapered glass capillary has the advantages of good chemical resistance, low friction, easy to manufacture and low cost and is suitable for chemical and biological analysis. The minimum size of the spherical droplets can reach 12 μm in diameter and about 1 picolitre in volume. The percentage of the droplets with single 5 μm-diameter polystyrene bead can reach 40% when the droplet size is 40 μm and the concentration of the bead suspension is 1×107 beads per milliliter. The experiment result can be applied in droplet-based single cell encapsulating and analyzing.

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Meng, De, Pinqi Xia, and Laishou Song. "MIMOMH feed-forward adaptive vibration control of helicopter fuselage by using piezoelectric stack actuators." Journal of Vibration and Control 24, no. 23 (February 15, 2018): 5534–45. http://dx.doi.org/10.1177/1077546318757840.

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The vibration of a helicopter fuselage is mainly produced by the rotor exciting loads which are three forces and three moments containing harmonics in three directions at rotor hub center, and has the characteristic of large, steady and harmonic vibration. The active control of helicopter fuselage vibration by using inertia actuator needs to pay a heavy weight cost for achieving a good control effect. In this paper, a method for multi-input multi-output multi-harmonic (MIMOMH) feed-forward adaptive control of helicopter fuselage vibration by using piezoelectric stack actuators is presented. The method is composed of the harmonic coefficients identification and the MIMOMH feed-forward adaptive filtering algorithm, and has excellent characteristics such as light weight, fast response, wide working frequency range, adaptive ability and high effect. The numerical simulations for a frame structure scaled by the Z11 helicopter fuselage floor with four actuating inputs, four vibration outputs, three rotor exciting loads and the first three harmonic frequencies contained in each exciting load were performed, indicating that the vibration levels at objective points are reduced by 99% by using the method and are much lower than the results by only controlling the first harmonic frequency. When the phases, amplitudes and frequencies of exciting loads are changed, the method demonstrates an excellent adaptability to control vibration.

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Pukrushpan, Jay T., Huei Peng, and Anna G. Stefanopoulou. "Control-Oriented Modeling and Analysis for Automotive Fuel Cell Systems." Journal of Dynamic Systems, Measurement, and Control 126, no. 1 (March 1, 2004): 14–25. http://dx.doi.org/10.1115/1.1648308.

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Fuel Cells are electrochemical devices that convert the chemical energy of a gaseous fuel directly into electricity. They are widely regarded as a potential future stationary and mobile power source. The response of a fuel cell system depends on the air and hydrogen feed, flow and pressure regulation, and heat and water management. In this paper, we develop a dynamic model suitable for the control study of fuel cell systems. The transient phenomena captured in the model include the flow and inertia dynamics of the compressor, the manifold filling dynamics (both anode and cathode), reactant partial pressures, and membrane humidity. It is important to note, however, that the fuel cell stack temperature is treated as a parameter rather than a state variable of this model because of its long time constant. Limitations and several possible applications of this model are presented.

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Stevanovic, Zana, Gradimir Ilic, Mica Vukic, Predrag Zivkovic, Bratislav Blagojevic, and Milos Banjac. "CFD simulations of thermal comfort in naturally ventilated primary school classrooms." Thermal Science 20, suppl. 1 (2016): 287–96. http://dx.doi.org/10.2298/tsci150414171s.

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The purpose of Thermal Comfort is to specify the combinations of indoor space environment and personal factors that will produce thermal environment conditions acceptable to 80% or more of the occupants within a space. Naturally ventilated indoors has a very complex air movement, which depends on numerous variables such as: outdoor interaction, intensity of infiltration, the number of openings, the thermal inertia of walls, occupant behaviors, etc. The most important mechanism for naturally ventilated indoors is the intensity of infiltration and thermal buoyancy mechanism. In this study the objective was to determine indicators of thermal comfort for children, by the CFD model based on experimental measurements with modification on turbulent and radiant heat transfer mathematical model. The case study was selected on school children aged 8 and 9 years in primary school ?France Presern?, Belgrade. The purpose was to evaluate the relationships between the indoor environment and the subjective responses. Also there was analysis of infiltration and stack effect based on meterological data on site. The main parameters that were investigated are: operative temperature, radiant temperature, concentration of CO2 and air velocity. The new correction of turbulence and radiative heat transfer models has been validated by comparison with experimental data using additional statistical indicators. It was found that both turbulence model correct and the new radiative model of nontransparent media have a significant influence on CFD data set accuracy.

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Shin, Shin, and Kim. "The Market Sentiment Trend, Investor Inertia, and Post-Earnings Announcement Drift: Evidence from Korea’s Stock Market." Sustainability 11, no. 18 (September 19, 2019): 5137. http://dx.doi.org/10.3390/su11185137.

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We investigated whether post-earnings announcement drift (PEAD) in the Korean stock market is related to investor inertial behavior under a directional trend in market sentiment. Given that investors tend to procrastinate due to their belief in the persistence of the current market’s condition and thus underreact to earnings information, we examined whether this investor inertia influences the drift in stock price following an earnings announcement. Our findings show that when the market sentiment continues to shift upwardly (downwardly) over the pre- and post-earnings announcement period, positive (negative) drift occurs. Note that these results are robust to control for the effect of market sentiment at a specific point in time. We suggest that investors do not fully respond to new earnings information due to investor inertial behavior under the market sentiment with a consistent trend. Overall, our study sheds light on a determinant of PEAD as one of the market anomalies in terms of investors’ cognitive bias by documenting the relation between PEAD and investor inertia.

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Kychkin, Aleksey V., Oleg V. Gorshkov, Vladislav A. Selivanov, and Vitaliy A. Pavlov. "Technology for the soft implementing a digital twin into the IoT HVAC control loop." Journal Of Applied Informatics 16, no. 95 (October 29, 2021): 33–47. http://dx.doi.org/10.37791/2687-0649-2021-16-5-33-47.

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The development of application software for cyber-physical systems of buildings involves the widespread use of Internet of Things (IoT) integration platforms. In practice, the flexible functionality of IoT platforms often leads to additional costs for software enhancement of existing and connection of new units, in particular digital twins. The paper proposes a technological solution for the implementation of a digital twin of the ventilation process in the IoT control loop of heating, ventilation and air conditioning (HVAC) systems for buildings and industrial facilities. The implementation and execution of the digital twin in the form of a dynamic simulation model in the object-oriented modelling language Modelica in the OpenModelica environment is considered. The IoT platform InfluxData, based on the TICK stack, is considered as an example of an integration environment. It is a horizontally-oriented IoT platform that contains the mechanism for collecting data from devices and the InfluxDB time-series database for storing metrics. To integrate simulation models on Modelica with InfluxDB, an OMPython server is proposed. In this case, the integration scripts are executed in the Python language, which as a result extends the traditional capabilities of the IoT platform significantly to the level of a digitally twinned control system. This HVAC control involves adapting control loops by taking into account the dynamics of the air distribution process over the ventilation network, evaluating and compensating for process inertia. The publication was prepared within the framework of the Academic Fund Program at the HSE University in 2020–2021 (grant № 21-04-039).

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Шимановский, А. О., and И. Е. Кракова. "MODELING OF VIBRATIONS AND STRESS-STRAIN STATE OF SANDWICH-PANEL PACKAGES DURING THEIR TRANSPORTATION." Stroitelʹnaâ mehanika i konstrukcii, no. 4(35) (December 19, 2022): 49–57. http://dx.doi.org/10.36622/vstu.2022.35.4.006.

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Выполнен анализ динамики и прочности пакетов сэндвич-панелей как трехслойных конструкций под действием нагрузок, приводящих к значительным деформациям при длительной транспортировке. Разработаны конечно-элементные модели, учитывающие особенности взаимодействия панелей, размещенных в транспортных пакетах. Получены значения собственных частот колебаний рассмотренных систем. Показано, что низшие частоты колебаний пакетов сэндвич-панелей лежат в диапазоне частот вынуждающих сил, возникающих при движении транспортного средства по дороге. Анализ напряжений, возникающих в панели нижнего яруса, показал, что в случае совместного действия сил инерции, связанных с торможением автомобиля, сил тяжести и сил прижатия ремней крепления при числе десяти и более панелей в штабеле в среднем слое нижней панели возникают напряжения, превышающие предел прочности материала. Полученные результаты показали, что обеспечить прочность транспортируемых панелей при перевозке их пакетов в два яруса возможно только при жесткой упаковке панелей нижнего яруса. The analysis of the dynamics and strength of sandwich-panel packages, as three-layer structures, under the action of loads, leading to significant deformations during long-term transportation, was carried out. Finite element models have been developed that take into account the peculiarities of the panels placed in transport packages interaction. The values of Eigen frequencies of considered systems oscillations are obtained. It is shown that the lowest oscillation frequencies of the sandwich panel packages lie in the frequency range of the driving forces that occur when the vehicle moves along the road. An analysis of the stresses arising in the panel of the lower tier showed that in the case of the combined action of the forces of inertia associated with the braking of the car, the forces of gravity and the forces of pressing the fastening belts with a number of ten or more panels in a stack, stresses arise in the middle layer of the lower panel that exceed the tensile strength material. The obtained results showed that it is possible to ensure the strength of the transported panels when transporting their packages in two tiers only if the panels of the lower tier are rigidly packed.

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Tykocinski, Orit, Roni Israel, and Thane S. Pittman. "Inaction Inertia in the Stock Market1." Journal of Applied Social Psychology 34, no. 6 (June 2004): 1166–75. http://dx.doi.org/10.1111/j.1559-1816.2004.tb02001.x.

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Swing, Kelly. "Inertia is speeding fish-stock declines." Nature 494, no. 7437 (February 2013): 314. http://dx.doi.org/10.1038/494314b.

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BILIAS, YANNIS, DIMITRIS GEORGARAKOS, and MICHAEL HALIASSOS. "Portfolio Inertia and Stock Market Fluctuations." Journal of Money, Credit and Banking 42, no. 4 (June 2010): 715–42. http://dx.doi.org/10.1111/j.1538-4616.2010.00304.x.

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Lü, Q. F., X. F. Wang, K. Lu, and R. H. Huan. "Nonlinear Stochastic Optimal Control Using Piezoelectric Stack Inertial Actuator." Shock and Vibration 2020 (August 18, 2020): 1–7. http://dx.doi.org/10.1155/2020/5372045.

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An optimal control strategy for the random vibration reduction of nonlinear structures using piezoelectric stack inertial actuator is proposed. First, the dynamic model of the nonlinear structure considering the dynamics of a piezoelectric stack inertial actuator is established, and the motion equation of the coupled system is described by a quasi-non-integrable-Hamiltonian system. Then, using the stochastic averaging method, this quasi-non-integrable-Hamiltonian system is reduced to a one-dimensional averaged system for total energy. The optimal control law is determined by establishing and solving the dynamic programming equation. The proposed control law is analytical and can be fully executed by a piezoelectric stack inertial actuator. The responses of optimally controlled and uncontrolled systems are obtained by solving the Fokker–Planck–Kolmogorov (FPK) equation to evaluate the control effectiveness of the proposed strategy. Numerical results show that our proposed control strategy is effective for random vibration reduction of the nonlinear structures using piezoelectric stack inertial actuator, and the theoretical method is verified by comparing with the simulation results.

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Huang, Shunwu, Wang Chang, and Lan Zheng. "Earnings Surprise, Portfolio Inertia and Stock Price Volatility." Journal of Systems Science and Information 3, no. 4 (August 25, 2015): 301–20. http://dx.doi.org/10.1515/jssi-2015-0301.

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AbstractFrom the perspective of the mediation effect, this paper investigates whether institutional investors adjust their portfolios according to the listed companies earnings surprise. We find that the portfolio adjustments by institutional investors exert the mediation effect on the relationship between earnings surprise and stock price volatility. Institutional investors actively manage their portfolios in the rising market, which induces the stock price volatility; while they less adjust their portfolio in the falling market, the volatility declines. This paper helps understand the role of institutional investors in the fluctuation of stock prices, and provides a new basis for decision making of regulatory administration.

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Pfajfar, Damjan, and Emiliano Santoro. "Determinacy, stock market dynamics and monetary policy inertia." Economics Letters 112, no. 1 (July 2011): 7–10. http://dx.doi.org/10.1016/j.econlet.2011.02.033.

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Mier, Frank, Raj Bhakta, Nicolas Castano, John Garcia, and Michael Hargather. "Experimental Measurement of Steady and Transient Liquid Coiling with High-Speed Video and Digital Image Processing." Fluids 3, no. 4 (December 15, 2018): 107. http://dx.doi.org/10.3390/fluids3040107.

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Liquid coiling occurs as a viscous fluid flows into a stagnant reservoir causing a localized accumulation of settling material, which coils into a stack as it accumulates. These coiling flows are broadly characterized into three primary coiling regimes of viscous, gravitational, or inertial coiling, based on the velocity of the falling fluid, the height of the fall, the radius of the fluid rope, the stack height, and the fluid properties including viscosity. A computer-controlled flow delivery apparatus was developed here to produce precisely controlled flow conditions to study steady and transitional coiling regimes with independently varied parameters. Data were recorded using high-speed digital video cameras and a purpose-built digital image processing routine to extract rope and stack dimensions as well as time-resolved coiling frequency. The precision of the setup and data analysis methods allowed a detailed study of the transition between gravitational and inertial flow regimes. The results show a smooth transition between the regimes, with no evidence of the inertial-gravitational regime. Unsteady coiling was able to be momentarily produced by applying a perturbation to the system, but the unstable regime quickly decayed to either the base inertial or gravitational regime.

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PASHKOV, Nikolai N. "EQUATION OF MOTION MAGNETIC LEVITATION ROLLING STOCK." Transportation systems and technology 1, no. 1 (March 15, 2015): 59–69. http://dx.doi.org/10.17816/transsyst20151159-69.

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This article deals with the problem of control the trajectory of the crew magnetic levitation relative trajectory of the software regarding the track structure of the perturbation of the gravitational and magnetic fields levitation systems, lateral stabilization and traction. The crew is presented as a system of rigid bodies, whose motion is subject to gravitational and electromagnetic forces. The spatial displacement with limited powers of levitation and lateral stabilization regarding a discrete track structure are selected by drawing up the estimated equations of the dynamics of the crew as inertial coordinates of the centers of mass of solids. The coordinates of any point on the carriage in a local coordinate system are converted in the coordinate system associated with the center of mass of the crew to bring the point of application of external force to the center of mass of the crew. A general model of the dynamics of the crew is based on the equation of Lagrange-Maxwell which binds to the active mass of the external forces of gravity that govern the electromagnetic force, the force of inertia and friction. The kinetic energy of the mechanical system is defined by the velocity projections on the axis of the fixed coordinate system as a quadratic form. The crew simulated magneto elastic coupling with the track structure changing the potential energy of magnetic levitation and lateral stabilization at the deformation of the object or the displacement and rotation of the center of mass of the crew in three-dimensional space. The inverse problem of dynamics is solved to determine the control forces for a given trajectory of the crew magnetic levitation. The equations of motion the crew on a magnetic cushion are linearized regarding increments relative coordinates of the centers of mass of the crew vector and presented in the form of equations of the phase space of states.

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Willard, Charles L. "Inertial actuator with multiple flexure stacks." Journal of the Acoustical Society of America 124, no. 1 (2008): 25. http://dx.doi.org/10.1121/1.2960788.

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Coleman, Thomas, and Dan Edidin. "Inertial Chow rings of toric stacks." manuscripta mathematica 156, no. 3-4 (November 2, 2017): 341–69. http://dx.doi.org/10.1007/s00229-017-0982-z.

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Cox, Carla, and Diana Isaacs. "Why Are We Stuck? Therapeutic Inertia in Diabetes Education." Diabetes Spectrum 33, no. 1 (February 2020): 16–21. http://dx.doi.org/10.2337/ds19-0003.

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Elmer, Timon, Nicole Geschwind, Frenk Peeters, Marieke Wichers, and Laura Bringmann. "Getting stuck in social isolation: Solitude inertia and depressive symptoms." Journal of Abnormal Psychology 129, no. 7 (October 2020): 713–23. http://dx.doi.org/10.1037/abn0000588.

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Лисица, Максим Иванович. "AN EMPIRICAL APPROACH TO THE STUDY OF INFORMATION EFFICIENCY AND HISTORICAL INERTIA OF STOCK MARKETS." «Izvestia vyssih uchebnyh zavedenij. Seria «Ekonomika, finansy i upravlenie proizvodstvom», no. 4 (46) (December 29, 2020): 64–70. http://dx.doi.org/10.6060/ivecofin.2020464.506.

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There is no consensus among experts (both theorists and practitioners) about the possibilities of forecasting in organized markets, and therefore two points of view have been formed. Proponents of the first believe that the capital market is information-efficient and does not provide grounds for reliable prediction of market prices, since they can only change if news arrives, the appearance of which does not follow any regularity, therefore, there are no regularities in pricing. Proponents of the second theory admit historical inertia in pricing, at least in organized stock markets, justifying this by the inertia of market actors ' thinking, which extends to decision-making processes, hence the grounds for relatively reliable forecasting of market prices. Both points of view can be supported statistically, but there is no mathematical evidence in favor of either of them. However, if we accept as exhaustive the results of the empirical test, which is based on the tools of probability theory and mathematical statistics, we will have to accept the presence of historical inertia in pricing in organized stock markets, which may increase or decrease, but is always present

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Palomino-Tamayo, Walter, and Juan S. Timaná. "Creating firm value, overcoming organizational inertia through the marketing value chain." Academia Revista Latinoamericana de Administración 35, no. 1 (November 19, 2021): 20–36. http://dx.doi.org/10.1108/arla-06-2021-0119.

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PurposeTechnology may produce disruptive changes and market turbulence in any industry. Organizational inertia becomes relevant as a factor that adversely affects organizational transformation; this study aims to examine how to overcome it and its consequences to firms.Design/methodology/approachThe model estimation with seemingly unrelated regression and two-stage least square. The authors build a data set of years 2015–2019 from the Lima Stock Exchange firms to test the hypotheses.FindingsIn this research, using the evolutionary-ecological theory of Hannan and Freeman, the study shows the consequences of organizational inertia on marketing intensity and subsequently on firms' financial results.Originality/valueThis study presents an inter-functional model that links organizational behavior, marketing and finance functions, through the marketing value chain to overcome organizational inertia and create firm value.

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31

Lee, Jung Sick, and Young Jin Chang. "Electron Microscopical Description on the Egg Stalk-like Structure of the Rockfish, Sebastes inermis (Teleostei: Scorpaenidae)." Korean Journal of Fisheries and Aquatic Sciences 35, no. 2 (March 1, 2002): 130–34. http://dx.doi.org/10.5657/kfas.2002.35.2.130.

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32

Omelyanenko, V. I., Ie S. Riabov, L. V. Overianova, and H. V. Omelianenko. "Traction electric drive based on fuel cell batteries and on-board inertial energy storage for multi unit train." Electrical Engineering & Electromechanics, no. 4 (July 29, 2021): 64–72. http://dx.doi.org/10.20998/2074-272x.2021.4.08.

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The aim of the work is to study the possibility and features of the use of inertial storage devices in the traction electric drive of multi unit train with a power plant based on fuel cells. Methodology. The principle of power flow control in traction electric drives in the modes of acceleration and braking of rolling stock is proposed. The mathematical model of the traction electric drive in the form of the combination of three components: the train, the traction unit and the battery of fuel cells is developed. It was used to study the operation of a traction electric drive when solving a test traction task for rolling stock. Results. It is established that the use of inertial energy storage reduces hydrogen consumption by at least 25 %, which increases the mileage of rolling stock between equipment by more than 30 %. Originality. The traction electric drive on the basis of fuel elements and the inertial energy storage for the multi unit train is offered. The work of the proposed traction electric drive in solving the test traction problem for rolling stock is investigated. Practical significance. A mathematical model of the traction electric drive has been developed. The test traction problem for rolling stock is solved.

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PANDEY, RAS B., and DIETRICH STAUFFER. "SEARCH FOR LOG-PERIODIC OSCILLATIONS IN STOCK MARKET SIMULATIONS." International Journal of Theoretical and Applied Finance 03, no. 03 (July 2000): 479–82. http://dx.doi.org/10.1142/s0219024900000437.

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Using Chowdhury's simplification of the Cont–Bouchaud percolation algorithm, and including inertia (trading momentum) as well as a nonlinear restoring force (pricing pressure), we find spontaneous oscillations, which for suitable parameters have at first an exponentially increasing period. They seem to mimic the approximate log-periodic oscillations found by Johansen and Sornette in the Nikkei index after the burst of the Japanese bubble a decade ago.

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Koval, Peter, Peter Kuppens, Nicholas B. Allen, and Lisa Sheeber. "Getting stuck in depression: The roles of rumination and emotional inertia." Cognition & Emotion 26, no. 8 (December 2012): 1412–27. http://dx.doi.org/10.1080/02699931.2012.667392.

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35

Toroptsev, Evgeny. "Structural inertia of economic systems." Economics and the Mathematical Methods 58, no. 1 (2022): 38. http://dx.doi.org/10.31857/s042473880016564-9.

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Systemic inertia forms a transdisciplinary field of studies, which includes interests of natural sciences, technical studies, humanitarian studies, socio-economic studies, etc. Economic science mainly relied on the methods of economic theory and philosophy to analyze this phenomenon. The globality of this subject impeded the formalization of research, and numerical interpretation of inertia were limited to the introduction of a coefficient in an economic and mathematical model. At the same time, the opportunity of getting numerical values of structural inertia in the industry coordinates was provided by basic dynamic input-output balance model, written as a system of basic differential equations. This model’s capital coefficients matrix (according to V. Leontief) is non-singular and can be called the matrix of interindustry inertia. Its elements have time dimensionality. This research presents the methodology for calculating the matrix. Its dimensionality is equal to the dimensionality of the matrix of the formation of the output of goods and services published by ROSSTAT with the interval of two years. This methodology consists of verifiable sequence of algebraic transformations within the input-output methodology with the specified matrix. This research represents the inertia, related to the processes of formation of basic stock, and the inertia of the formation of the gross value added of Russian economy. The high practical importance of the research consists in the development and demonstration of the economic and mathematical apparatus for contrastive analysis of structural dynamic properties of different economies when they are modeled in the coordinates of the same industries.

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Toroptsev, Evgeny. "Structural inertia of economic systems." Economics and the Mathematical Methods 58, no. 1 (2022): 38. http://dx.doi.org/10.31857/s042473880016565-0.

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Systemic inertia forms a transdisciplinary field of studies, which includes interests of natural sciences, technical studies, humanitarian studies, socio-economic studies, etc. Economic science mainly relied on the methods of economic theory and philosophy to analyze this phenomenon. The globality of this subject impeded the formalization of research, and numerical interpretation of inertia were limited to the introduction of a coefficient in an economic and mathematical model. At the same time, the opportunity of getting numerical values of structural inertia in the industry coordinates was provided by basic dynamic input-output balance model, written as a system of basic differential equations. This model’s capital coefficients matrix (according to V. Leontief) is non-singular and can be called the matrix of interindustry inertia. Its elements have time dimensionality. This research presents the methodology for calculating the matrix. Its dimensionality is equal to the dimensionality of the matrix of the formation of the output of goods and services published by ROSSTAT with the interval of two years. This methodology consists of verifiable sequence of algebraic transformations within the input-output methodology with the specified matrix. This research represents the inertia, related to the processes of formation of basic stock, and the inertia of the formation of the gross value added of Russian economy. The high practical importance of the research consists in the development and demonstration of the economic and mathematical apparatus for contrastive analysis of structural dynamic properties of different economies when they are modeled in the coordinates of the same industries.

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Jäger, W., H. Dreizler, H. Mäder, J. Sheridan, and C. T. Walls. "The Microwave Spectrum of 4-Methylisoxazole: 14N Nuclear Quadrupole Coupling, Methyl Internal Rotation and Electric Dipole Moment." Zeitschrift für Naturforschung A 42, no. 5 (May 1, 1987): 501–6. http://dx.doi.org/10.1515/zna-1987-0513.

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The microwave spectrum of 4-methylisoxazole has been investigated in the frequency range from 8 to 40 GHz, employing both Stark and Fourier transform spectroscopy. We present the results from a 14N quadrupole hyperfine structure, a fourth-order centrifugal distortion and an IAM methyl internal rotation analysis. The components of the electric dipole moment with respect to the principal axes of inertia have been obtained from the Stark splittings of some rotational lines.

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Zhong, Bowen, Bin Liu, Ziqi Jin, Zhenhua Wang, and Lining Sun. "Cubic centimeter robot based on inertial stick–slip driving." Microsystem Technologies 26, no. 2 (July 25, 2019): 437–45. http://dx.doi.org/10.1007/s00542-019-04557-2.

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Wen, Jian Ming, Ji Jie Ma, Zhong Hua Zhang, Guang Ming Cheng, and Jun Wu Kan. "Inertial Piezoelectric Micro Rotary Actuator." Advanced Materials Research 487 (March 2012): 208–11. http://dx.doi.org/10.4028/www.scientific.net/amr.487.208.

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A newly inertial piezoelectric rotary actuator is proposed based on controlling the orderly changes of friction force between the rotator and supporting faces in mechanical way. The dynamic simulation model of the actuator is derived. A prototype small inertial rotary actuator characterized by two symmetric piezoelectric stacks has been fabricated based on the proposed method. The actuator can rotate when it is powered with a square-wave or sine-wave voltage. The experimental and simulation results show that its angular speed is proportional to both the driving voltage’s amplitude and the frequency. The experimental results also show good agreement with the simulation analysis.

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Ye, Tao, and Joseph L. Bull. "Direct Numerical Simulations of Micro-Bubble Expansion in Gas Embolotherapy." Journal of Biomechanical Engineering 126, no. 6 (December 1, 2004): 745–59. http://dx.doi.org/10.1115/1.1824131.

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We are currently developing a novel gas embolotherapy technique that involves the selective, acoustic vaporization of liquid perfluorocarbon droplets in or near a tumor as a possible treatment for cancer. The resulting bubbles can then stick within the tumor vasculature to occlude blood flow and “starve” the tumor. The potential development of high stresses during droplet vaporization is a major concern for safe implementation of this technique. No prior study, either experimentally or theoretically, addresses this important issue. In this work, the acoustic vaporization procedure of the therapy is investigated by direct numerical simulations. The nonlinear, multiphase, computational model is comprised of an ideal gas bubble surrounded by liquid inside a long tube. Convective and unsteady inertia, viscosity, and surface tension affect the bubble dynamics and are included in this model, which is solved by a novel fixed-grid, sharp-interface, moving boundary method. We assess the potential for flow-induced wall stresses to rupture the vessel or damage the endothelium during vaporization under a range of operating conditions by varying dimensionless parameters—Reynolds, Weber, and Strouhal numbers, inertial energy and initial droplet size. It is found that the wall pressure is typically highest at the start of the bubble expansion, but the maximum wall shear stress occurs at a later time. Smaller initial bubble diameters, relative to the vessel diameter, result in lower wall stresses.

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Kasten, W., and H. Dreizler. "Investigation of the 14N Quadrupole Hyperfine Structure and the Stark Effect of Methyl Isocyanate and Methyl Isothiocyanate by Microwave Fourier Transform Spectroscopy." Zeitschrift für Naturforschung A 41, no. 4 (April 1, 1986): 637–40. http://dx.doi.org/10.1515/zna-1986-0408.

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The nitrogen 14N quadrupole hyperfine structure and the Stark effect in the rotational spectra of methyl isocyanate and methyl isothiocyanate were investigated by high resolution microwave Fourier transform spectroscopy.The components of the coupling tensor in the principal inertia axis system and the n a components of the dipole moments have been determined.

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Zhong, Bowen, Jie Zhu, Ziqi Jin, Haidong He, Lining Sun, and Zhenhua Wang. "Improved inertial stick-slip movement performance via driving waveform optimization." Precision Engineering 55 (January 2019): 260–67. http://dx.doi.org/10.1016/j.precisioneng.2018.09.016.

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Dalbe, Marie-Julie, Richard Villey, Matteo Ciccotti, Stéphane Santucci, Pierre-Philippe Cortet, and Loïc Vanel. "Inertial and stick-slip regimes of unstable adhesive tape peeling." Soft Matter 12, no. 20 (2016): 4537–48. http://dx.doi.org/10.1039/c6sm00119j.

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Gatu Johnson, M., P. J. Adrian, K. S. Anderson, B. D. Appelbe, J. P. Chittenden, A. J. Crilly, D. Edgell, et al. "Impact of stalk on directly driven inertial confinement fusion implosions." Physics of Plasmas 27, no. 3 (March 2020): 032704. http://dx.doi.org/10.1063/1.5141607.

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Ma, Ji Jie, Jian Ming Wen, Ping Zeng, Jun Wu Kan, and Zhong Hua Zhang. "Dynamical Research on a Micro-Displacement Actuator Based on V-Type Guide-Way." Advanced Materials Research 305 (July 2011): 330–34. http://dx.doi.org/10.4028/www.scientific.net/amr.305.330.

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A new type of the micro-displacement device based on V-shaped groove by using piezoelectric stack as the driver was presented. The performance characteristic of the driving device was introduced and its working mechanism was discussed. the dynamic formulation of inertial actuator is established, by using matlab software, the kinetic simulation of the actuator is carried out, the structure of newly inertial actuator is designed and manufactured. The simulation and experiment of the actuator is conducted. The simulation results agree well with the experimental results indicates that the simple associated symmetry electrical signal can provide stable stepping movement, the speed of 0.5mm/s, high resolution of 1μm, maximum loading capacity of 600g.

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Meyer, Michael, and Helmut Dreizler. "The Ground State Microwave Spectrum of 2-Fluoropropane." Zeitschrift für Naturforschung A 43, no. 2 (February 1, 1988): 138–42. http://dx.doi.org/10.1515/zna-1988-0208.

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We determined the internal rotation barrier V3 = 3.285 kcal/mol (13.74 kJ/mol) and the moment of inertia Iα = 3.184 amuÅ2 of the methyl groups from the ground state microwave spectrum of 2-fluoropropane. Additionally the rotational constants, the quartic and some sextic centrifugal distortion constants are reported. The analysis of the Stark effect leads to the dipole moment 1.958 D.

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Liu, Wei Hua, Yin Wang, Wei Qing Huang, and Qing Jun Ding. "A Linear Stepping Piezoelectric Motor Using Inertial Impact Driving." Applied Mechanics and Materials 226-228 (November 2012): 693–96. http://dx.doi.org/10.4028/www.scientific.net/amm.226-228.693.

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With the rapid development of modern precision manufacturing industry,actuators with high resolution and long stroke are needed in many application fields. Linear piezoelectric motors adopting inertial impact driving mechanism has been driving the interests of many researchers for simple structure and compact size. To increase the efficiency of this type of stepping linear motor, a motor using two piezoelectric stacks was proposed in this work. Two piezoelectric stacks were placed in vertical and were pre-tightened by an elastic thin plate. Support for the stator was designed. Operation principle of this motor was analyzed. To validate this operation principle, a prototype was fabricated and testing on this prototype was conduct too. By applying saw wave voltage signal to piezoelectric stacked in this prototype, the stator of the motor is able to push its mover move with pace length of 2 micrometer.

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Zhang, Nong, Jin Zhang, and Yu Wang. "Experimental Verification of Stick–slip Motion between Two Rolling Contact Surfaces." Advanced Materials Research 230-232 (May 2011): 1362–66. http://dx.doi.org/10.4028/www.scientific.net/amr.230-232.1362.

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In this paper, a simplified drive train model with stick-slip nonlinearity is introduced for the study of stick-slip motion between the driving tires and the flywheel. Laboratory based tests are designed to investigate stick-slip motion of the tires contacting with the flywheels which simulate vehicle inertia. A description of the powertrain test rig, the associated instrumentation, the test inputs and operation conditions are provided. The experimental results are similar to those obtained from the numerical analysis using the introduced drive train model. They verify the validity of the stick-slip model, and demonstrate that stick-slip occurred frequently between the driving tires and the flywheels. The normal tire force applied to the flywheel is one of the key parameters affecting stick-slip motion. And there exists an upper limit beyond which the tire and flywheel will stick together at all time. It is found that the frequency of stick-slip motion is independent of normal tire force and is close to the natural frequency of the tire-flywheel contacting power transmitting system.

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Deutsch, C., H. B. Nersisyan, and A. Bendib. "Diagnosing dense and magnetized plasmas irradiated by a petawatt laser." Laser and Particle Beams 34, no. 1 (November 30, 2015): 61–71. http://dx.doi.org/10.1017/s0263034615000919.

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AbstractWe survey the present status and potentialities of diagnostics for arbitrary magnetized plasmas of inertial confinement fusion concern. These diagnostics include: Faraday rotation, inverse Faraday effect, Thomson scattering, Stark–Zeeman line broadening as well as proton stopping for any ratio, of the particles plasma frequency to cyclotron frequency. This presentation is timely motivated by recent experiments highlighting laser-produced kilo Teslas and nearly steady magnetic fields in inertial fusion plasmas. Positive synergies due to diagnostics combinations are also addressed.

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Shih, Tsan-Hsing, and J. L. Lumley. "Second-order modelling of particle dispersion in a turbulent flow." Journal of Fluid Mechanics 163 (February 1986): 349–63. http://dx.doi.org/10.1017/s002211208600232x.

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A set of second-order modelled equations for the motion of particles are presented. We consider the effects of the particle inertia and the crossing-trajectories effect on the particle dispersion. A simple case of a particle mixing layer in a decaying homogeneous turbulence for light and heavy particles is calculated. The results show that the crossing-trajectories effect on particle dispersion is very significant, while inertia only has a slight effect. This behaviour has been observed in experiments (Wells & Stock 1983) and is well predicted by an asymptotic analysis (Csanady, 1963). The calculation also shows that there is a significant difference between Favre-averaged particle velocity and conventional-averaged particle velocity in the low-particle-concentration region. All calculations are in good agreement with Wells & Stock's experimental data.

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Journal articles on the topic 'Inertia stack'

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