Passive Part Research Articles

Energy cascades in active-grid-generated turbulent flows

The energy cascade and diverse turbulence properties of active-grid-generated turbulence were studied in a wind tunnel via hot-wire anemometry. To this aim, two active grid protocols were considered. The first protocol is the standard triple-random mode, where the grid motors are driven with random rotation rates and directions, which are changed randomly in time. This protocol has been extensively used due to its capacity to produce higher values of $Re_\lambda$ than its passive counter part, with good statistical homogeneity and isotropy. The second protocol was a static or open grid mode, where all grid blades were completely open, yielding the minimum blockage attainable with our grid. Centreline streamwise profiles were measured for both protocols and several inlet velocities. It was found that the turbulent flow generated with the triple-random protocol evolved in the streamwise direction consistently with an energy dissipation scaling of the form $\varepsilon=C_\varepsilon u^{\prime3}/L$, with $C_\varepsilon$ being a constant, $L$ the longitudinal integral length-scale, and $u^\prime$ the rms of the longitudinal velocity fluctuations. Conversely for the open-static grid, the energy dissipation followed a non-equilibrium turbulence scaling, namely, $C_\varepsilon \sim Re_G/Re_L$, where $Re_G$ is a global Reynolds number based on the inlet conditions of the flow, and $Re_L$ is based on the local properties of the flow downstream the grid. Furthermore, this open-static grid mode scaling exhibits important differences with other grids, as the downstream location of the peak of turbulence intensity is a function of the inlet velocity. It was also found that a rather simple theoretical model can predict the value of $C_\varepsilon$ based on the number density of zero-crossings of the longitudinal velocity fluctuations. This theory is valid for both active grid operating protocols.

Negative Capacitance as Universal Digital and Analog Performance Booster for Complementary MOS Transistors

Boltzmann electron energy distribution poses a fundamental limit to lowering the energy dissipation of conventional MOS devices, a minimum increase of the gate voltage, i.e. 60 mV, is required for a 10-fold increase in drain-to-source current at 300 K. Negative Capacitance (NC) in ferroelectric materials is proposed in order to address this physical limitation of CMOS technology. A polarization destabilization in ferroelectrics causes an effective negative permittivity, resulting in a differential voltage amplification and a reduced subthreshold swing when integrated into the gate stack of a transistor. The novelty and universality of this approach relate to the fact that the gate stack is not anymore a passive part of the transistor and contributes to signal amplification. In this paper, we experimentally validate NC as a universal performance booster: (i) for complementary MOSFETs, of both n- and p-type in an advanced CMOS technology node, and, (ii) for both digital and analog significant enhancements of key figures of merit for information processing (subthreshold swing, overdrive, and current efficiency factor). Accordingly, a sub-thermal swing down to 10 mV/decade together with an enhanced current efficiency factor up to 105 V−1 is obtained in both n- and p-type MOSFETs at room temperature by exploiting a PZT capacitor as the NC booster. As a result of the subthreshold swing reduction and overdrive improvement observed by NC, the required supply voltage to provide the same on-current is reduced by approximately 50%.

Interactive Component in Oral Narratives of Preschool Children: on the Formulation of Hypothesis

The article presents an effort to elaborate the hypothesis for the experimental research devoted to interactive component in the oral narratives of preschool children. It is vital for psycholinguistics to reach a close approach to understanding of the essence of narrative processes which have in ontogenesis their own specifics, and according to some researches, these specifics are presented in indirect character of the process of narrative creation by child in the form of his verbal interaction with an adult.
 We assume that in order to reveal the ontogenetic cognitive discursive mechanisms involved in the process of narration, it is necessary to correlate the regularities of the verbal interaction of the participants in the narrative situation with the overall narrative tasks coming up in narrative process.
 Mеthodology, purpose and tasks of the research are determined by experimentally-genetic method (L.S. Vygotsky) put forward as main requirements «differentiation of the analysis of a thing and analysis of the process», «genetic restoration of all moments of the process development». The following of these requirements means a close following of the process of narrative development in its dynamics and the peculiarities of its formation at different stages of child’s development, paying attention to frequency facts as well as facts overcoming the limits of «narrow» phenomenon – narrative text.
 To work out the hypothesis the narrative material of the earlier made experiment with a group of 3 to 7 age children was used in which an adult took a passive part. The task was to tell the story. The material was not subjected to any analysis for the reason of the adult’s presence during the storytelling. The analysis of oral histories with interactive component included the following tasks: a) choose regular sequences of utterances in the dialogic interaction of child and adult; b) define the functional purpose of the adult’s utterance in the course in the child’s storytelling.
 The obtained results show that the adult practically at every step of the child’s age is oriented on the child’s comprehension and analyzing episodes of the history, that is on child’s formation of his mental image of structural and event sequence in history. The results of the analysis enabled us to propose a hypothesis for the next research step in the field. Along the line of this hypothesis, in the verbal ontogenesis the very nature of oral story as a multifaceted phenomenon of the discursive activity of man brings up to the surface the inner mechanisms of narration which have dialogue basis.

Is reaction time altered by mental or physical exertion?

Reaction time, classically divided into premotor time and electromechanical delay (EMD), can be determinant in daily life or sport situations. While some previous studies reported a negative impact of both muscle and mental fatigue on reaction time, the respective contributions of premotor time and EMD to the changes of reaction time remains unclear. The aim of the study was, therefore, to assess the effects of both muscle and mental effort on reaction time and its components. Thirteen subjects performed three conditions (mental effort condition, i.e., 14min of a mathematical cognitive task; muscle effort condition, i.e., intermittent contractions of the biceps brachii; control condition, i.e., watching a documentary). Before and after each condition, reaction time, premotor time and EMD were measured during voluntary contractions of the biceps brachii. EMD was also measured during evoked contractions of the biceps brachii to separate the parts due to the onset of muscle fascicle motion and the onset of force production. Reaction time and premotor time remained stable regardless of the condition considered (all P values > 0.05). EMD increased only after the muscle effort condition (+ 25% during voluntary contractions, no significant; + 17% during evoked contractions, P = 0.001), mainly due to an increase in the passive part of the series elastic component. Our study showed that neither mental nor muscle effort has a negative effect on simple reaction time during voluntary contractions.

Simple Impedance Response Formulas for the Dispersive Interaction Rates in the Effective Hamiltonians of Low Anharmonicity Superconducting Qubits

For superconducting quantum processors consisting of low anharmonicity qubits such as transmons we give a complete microwave description of the system in the qubit subspace. We assume that the qubits are dispersively coupled to a distributed microwave structure such that the detunings of the qubits from the internal modes of the microwave structure are stronger than their couplings. We define qubit ports across the terminals of the Josephson junctions and drive ports where transmission lines carrying drive signals reach the chip and we obtain the multiport impedance response of the linear passive part of the system between the ports. We then relate interaction parameters in between qubits and between the qubits and the environment to the entries of this multiport impedance function: in particular we show that the exchange coupling rate J between qubits is related in a simple way to the off-diagonal entry connecting the qubit ports. Similarly we relate couplings of the qubits to voltage drives and lossy environment to the entries connecting the qubits and the drive ports. Our treatment takes into account all the modes (possibly infinite) that might be present in the distributed electromagnetic structure and provides an efficient method for the modeling and analysis of the circuits.

Passive ISAR part I: framework and considerations

In part I of a two-part passive imaging series, a comprehensive framework for imaging of air targets with passive radar (PR) systems is developed. All operations necessary to convert raw sample data into two-dimensional imagery are touched on. The bistatic geometries, relatively narrow signal bandwidths, and low centre frequencies of most PR illuminators are considered along with their impact on image formation procedures. The core PR processing stages stemming from the illuminators' waveform properties are also examined within this context. The various stages of translational motion compensation are shown to have significant impact on image quality, while target tracking data aids estimation of the apparent target rotation. In turn, this enables cross-range scaling for more advanced methods of image formation to a known image formation plane. Thus, the established framework establishes necessary operations for extension to the multistatic imaging case. The framework is validated in simulation with parameters in accordance with digital television broadcast signals.

Passive ISAR part II: narrowband imaging

In part II of the passive inverse synthetic radar (P-ISAR) sequence, implications of narrow signal bandwidths on image formation procedures are considered within the previously developed P-ISAR framework of part I. Specifically, the case of single-channel digital television imaging systems is evaluated. For average sized airborne targets illuminated with narrow signal bandwidths, the response is confined to one or two down-range resolution cells, which has significant impact on both inverse synthetic aperture radar (ISAR) resolutions and motion compensation procedures. Simulated results demonstrate that a non-parametric autofocus method, phase gradient algorithm, does not necessarily converge to a properly focused image. Contrast and entropy metrics are also shown to be insufficient for the narrowband imaging case. A parametric Doppler centroid approach is proposed for phase compensation, with resulting imagery closely resembling clairvoyant reconstruction. Finally, the proposed architecture is evaluated in full-scale experiments of commercial air targets, demonstrating the potential for discriminating large and small aircrafts.

Role of culture animation in preserving the spiritual values of the globalized society

Purpose of the article. The purpose of the article is to reveal the key ideas and principles of animation of culture in the historical and theoretical perspective, refinement of its etymological and semantic foundations as a socio-cultural phenomenon. Animation of culture is a socio-cultural phenomenon, a dynamic process of the formation of social relations connected with culture. The methodology of the research is based on an integrated combination of analytical, historical, culturological and comparative methods and generalization, which enables exploring historical theoretical origins, paradigms, and models of animation of culture as an important foundation for the construction of social and cultural capital. Scientific novelty lays in defining the essence and significance of animation of culture as an effective tool for combating exclusion of personality from the socio-cultural space, cultural activation, and social participation. Conclusion. Animation of culture at the present stage is becoming the more and more actual and popular method of activity in the cultural and social sphere, aimed at developing the creative potential of the passive part of the society. The purpose of animation of culture is to change the person, the surrounding reality, to find the way out of spiritual and intellectual apathy of a significant part of society through the culture and socio-cultural environment.

Efficient Sensitivity and Variability Analysis of Nonlinear Microwave Stages Through Concurrent TCAD and EM Modeling

An accurate, yet computationally efficient, computer-aided design (CAD) framework is proposed for the concurrent variability analysis of the active and a passive part of a radio frequency (RF)/microwave nonlinear stage. Both the active and passive parts are modeled, fully retaining a link to their physical and technological parameters. This allows for a global assessment of the nonlinear stage sensitivity and variability due to process variations. The active device is first modeled through technology CAD (TCAD); then, the model is implemented within an RF/microwave electronic design automation (EDA) circuit simulator through X-parameters. The passive part is modeled by means of accurate electromagnetic (EM) simulations and then taken into account in the circuit simulator through parametrized S-parameters. The method is demonstrated by analyzing a deep class AB power amplifier (PA) at 12 GHz in GaAs field-effect transistor (FET) technology. In particular, a Monte Carlo analysis of the output power variability around the nominal value of 26.4 dBm due to technological variations of both active device and output matching network is presented. The active device variability is shown to dominate over the passive structure one, even if up to 30% of the overall variance is due to the passive elements at intermediate input power levels.

дея загального блага (el bien general) у серії офортів “Лихоліття війни” (“Los desastres de la guerra”) Франсіско Гойї (за матеріалами фондів Національного музею мистецтв імені Богдана та Варвари Ханенків)

The ideas of the Enlightenment (first of all the French, with the most famous of its representatives – Jean-Jacques Rousseau, Charles-Louis de Secondat, Baron de La Brède et de Montesquieu and François-Marie Arouet Voltaire) not only influenced the political sphere of the Eighteenth century but also art. Francisco José de Goya y Lucientes (1746-1828) was directly convinced by these ideas: he took a passive part in the Napoleonic wars and was a friend of the prominent representatives of the Spanish Enlightenment. The study aims at analyzing interactions between text and image in the series of etchings of F. Goya “The Disasters of War” and the reception of the idea of «common good» in the etching 71 “Against the common good”. We have chosen several theoretical and methodological tools to deal with narrative and visual sources. Hermeneutics and semiotics belong to the specific methods used in the process of analysis of engravings. Comprehensive approach is determined by the usage of F. Goya both extraverbial and verbal (double numbers of etchings and artionims, ekfrasis) means. The methodological basis of the study is made up wit the principles of complexity, historicism and scientific character. The main methods were iconographic and iconological; empirical, prosopographical, method of synthetic and analytical source criticism; comparative-historical analysis. Probably, Francisco Goya, who also criticized the contemporary obscurantism in Spain (which is especially reflected in the series of etchings “Los Caprichos”), turned to the ideas of the French enlightenment, which gave rise to possibly unconscious reminiscences and allusions in his work. Thus, we are interested mainly how Goya indirectly or even unconsciously borrowed ideas from the Enlightenment movement, which spread rapidly all over Europe. In this case studying direct borrowings from J.-J. Rousseau’s ideas played only minor role.

Soft palate muscle activation: a modeling approach for improved understanding of obstructive sleep apnea.

A Hill model-based phenomenological method for muscle activation was used to investigate defectiveness of the palatal muscle tone during sleep for obstructive sleep apnea (OSA) patients. Based on the stretch-stress characteristic of muscle activation when the eccentric contraction is considered, a specifically defined phenomenological strain-energy function was used, as well as the Holzapfel-type strain-energy function for the passive part. A continuum mechanical framework, including the stress tensor and elasticity tensor, was obtained, based on the defined strain-energy function. The model parameters were obtained by fitting the constitutive model to experimental test data. Three-dimensional patient-specific geometry was modeled, accounting for the muscle tissue layer and based on the quantitative histology study of the soft palate. Anatomically representative boundary conditions for the finite element calculation were also considered. Palatal muscle activation level (electromyographic data) versus the negative pressure was defined in the simulations, and the patients' activation level was set to be lower than for the healthy people. The simulation results showed that reduced in activation level for the patients causes a less negative closing pressure, and this makes the soft palate more prone to collapse. In addition, if we account for the passive-active transfer displayed as the muscle contraction corresponding to the neurogenic reflex in the soft palate, the collapse is prevented. This numerical representation of the reduced activation for the OSA patients may provide increased understanding of OSA physiology.

CONCEPTUAL BASES FOR THE DEVELOPMENT OF HOTEL & RESTAURANT AND RESORT & RECREATIONAL INFRASTRUCTURE OF THE OIL & GAS COMPLEX

The article deals with the problems of the functioning of hotel & restaurant and resort & recreational infrastructure objects, which are subordinated to the domestic enterprises of the oil and gas complex. The emphasis is placed on the fact that in the sphere of management of Ukrainian oil and gas enterprises with full or predominant share of state property there are sanatoriums, recreation centers, hotels and health improving complexes, the main task of which is to organize services of accommodation, meals, rest, treatment and rehabilitation of workers.As a result of conducted research with using the objective characteristics of sectoral infrastructure services, the expert survey identified the main problems of their operation in market conditions, which are mainly related to the high degree of depreciation of the passive part of fixed assets and the shortage of personnel whose professional qualifications meets the needs of the institution and the requirements of a competitive market environment. In order to increase the efficiency of using the hotel & restaurant and resort & recreational infrastructure potential of the domestic oil and gas complex, the priority measures related to the necessity of forming a substrategy of the development of service sector objects with an emphasis on the development of their human resources are proposed.

3D reconstruction of GMAW pool surface using composite sensor technology

Weld pool is the most direct signal to reflect welding quality, that means measurement and reconstruction of the pool surface is one of the most urgent task in industrial robotic welding. A lot of researches have been done in this area, but the strong welding arc and the violent oscillation of weld pool affect their effectiveness. To better resolve this problem, a composite vision sensing system was proposed in our previous study, which consists of an active vision part and a passive vision part. The geometric parameters of the weld cross section and the weld pool have been successfully extracted by using this system. Based on the obtained information, the dynamic relationship between the weld speed and the bead geometric parameters is established by multistep predictive model based on neural network. By using the established model and iterative algorithm, the pool tail height is estimated in this paper. A spatial vision calibration is also proposed to calculate the real geometric parameters of the weld pool. Then the 3D surface of the weld pool is also reconstructed by the means of space curved surface fitting. Finally, the verification experiment is also conducted to verify the feasibility of this method.

An Early History of Neuroglial Research: Personalities

Neuroscience, like most other divisions of natural philosophy, emerged in the Hellenistic world following the first experimental discoveries of the nerves connecting the brain with the body. The first fundamental doctrine on brain function highlighted the role for a specific substance, pneuma, which appeared as a substrate for brain function and, being transported through the hollow nerves, operated the peripheral organs. A paradigm shift occurred in 17th century when brain function was relocated to the grey matter. Beginning from the end of the 18th century, the existence of active and passive portions of the nervous tissue were postulated. The passive part of the nervous tissue has been further conceptualised by Rudolf Virchow, who introduced the notion of neuroglia as a connective tissue of the brain and the spinal cord. During the second half of the 19th century, the cellular architecture of the brain was been extensively studied, which led to an in-depth morphological characterisation of multiple cell types, including a detailed description of the neuroglia. Here, we present the views and discoveries of the main personalities of early neuroglial research.

Split-Ring Resonator Antenna System With Cortical Implant and Head-Worn Parts for Effective Far-Field Implant Communications

We propose a spatially distributed antenna system to serve as the radio platform for RFID-inspired brain care applications. The antenna system consists of a passive wearable part placed on the scalp and a cortical implant part with split-ring resonator topology for miniaturization and antenna self-matching with a backscattering microsystem. We have optimized the antenna system in a hybrid head model combining anatomical features with a layered ellipsoid mimicking the major tissue layers of the human head in a controlled manner. Results from the wireless testing of the prototyped antenna system indicate that it enables remote powering and readout of a −18 dBm RFID microsystem at a distance of 1 m at 915 MHz with 10 mm implant depth. Moreover, our experiment shows that the studied system is tolerant toward misalignment between the implantable and wearable parts.

The transfer path analysis method on the use of artificial excitation: Numerical and experimental studies

Transfer path analysis (TPA) method is a powerful tool used to study the noise, vibration and harshness (NVH) behavior of mechanical systems. With the development of detecting and testing technology, more powerful and accurate tools for vibration and noise troubleshooting are required. The classical TPA works as the system is disassembled, and thus it is very time-consuming and the boundary conditions are not correct anymore. These topics makes classical TPA still an active research area.In this paper, a TPA method on the use of artificial excitation is presented. In the method artificial excitation is applied on the active part for providing sufficient incoherent forces to improve the estimation. The known force is applied on the passive part for establishing a relationship between the responses and loads. The advantages of this method are that it estimates the uncoupled transfer function of the passive part on the basis of in-situ measurements, without disassembling the system. The proposed method is validated by numerical and experimental case studies. Some remarks and practical aspects are discussed.

Inerter-based semi-active suspensions with low-order mechanical admittance via network synthesis

In this paper, the semi-active suspension design problem is concerned by proposing a novel design method incorporating inerters, where the overall semi-active suspension is divided into a passive part and a semi-active part. A mechanical network composed of springs, dampers and inerters is employed as the passive part, and a semi-active damper constitutes the semi-active part. For the conventional semi-active suspensions, the passive part is merely a parallel connection of a spring and a damper, and the main focus is on improving the semi-active part by proposing more effective control algorithms. In contrast, in this paper, the main idea is to improve the overall vehicle performance by improving the passive part instead of the semi-active part. Low-order admittance networks are employed in the passive parts, where some low-order positive real admittance functions are optimized, and then realized as specific mechanical networks by using network synthesis. A suboptimal control law, called steepest gradient control, is utilized in the semi-active part for the control of the semi-active damper. The proposed method is illustrated based on a quarter-car model, and numerical simulations based on a quarter-car and full-car model are performed to show the effectiveness of the proposed method. In contrast to the conventional semi-active suspensions without inerters, the proposed method can provide significant improvements (over 10% and 8% improvements for the quarter-car and full-car model cases, respectively) for the overall suspension performance involving ride comfort, suspension deflection, and road holding.

Management of the LCC considering industrial construction life cycle contracts

Currently the most urgent problem is increasing the efficiency of industrial construction in the green-field and brown-field formats. Introduction of the development method is a typical organizational form of industrial construction management. The method of program management is its variety. The article deals with the analysis of up-to-date strategic aspects of industrial property management. An important task is to create territorial and reproduction systems of industrial property based on life cycle cost (LCC) management. The paper describes the methodical approach to the evaluation of the life cycle cost of industrial property ownership. The evaluation covers the entire life cycle of the property item, from the stage of land development to finished item operation. It is proposed to use life cycle contracts for the development to increase the efficiency of industrial property management. The comparative analysis of life cycle contracts and similar contracts and subcontrator agreements in the area of construction concluded in the territory of Russia showed certain advantages of this approach. The article describes an approach to modeling of an efficient portfolio of industrial development orders. Results of modeling of the structure of the life cycle cost of industrial property ownership as the passive part of fixed funds by functions and stages for the estimated ownership cycle equal to 50 years are presented. Based on the research results the final life cycle cost of ownership for the end user – a resident or owner of the industrial park (IP) industrial property – is determined.

Heightened visual attention does not affect inner ear function as measured by otoacoustic emissions.

Previous research has indicated that inner ear function might be modulated by visual attention, although the results have not been totally conclusive. Conceivably, modulation of hearing might occur due to stimulation of the cochlea via descending medial olivocochlear (MOC) neurons. The aim of the present study was to test whether increased visual attention caused corresponding changes in inner ear function, which was measured by the strength of otoacoustic emissions (OAEs) recorded from the ear canal in response to a steady train of clicks. To manipulate attention, we asked subjects to attend to, or ignore, visual stimuli delivered according to an odd-ball paradigm. The subjects were presented with two types of visual stimuli: standard and deviant (20% of all stimuli, randomly presented). During a passive part of the experiment, subjects had to just observe a pattern of squares on a computer screen. In an active condition, the subject’s task was to silently count the occasional inverted (deviant) pattern on the screen. At all times, visual evoked potentials (VEPs) were used to objectively gauge the subject’s state of attention, and OAEs in response to clicks (transiently evoked OAEs, TEOAEs) were used to gauge inner ear function. As a test of descending neural activity, TEOAE levels were evaluated with and without contralateral acoustic stimulation (CAS) by broadband noise, a paradigm known to activate the MOC pathway. Our results showed that the recorded VEPs were, as expected, a good measure of visual attention, but even when attention levels changed there was no corresponding change in TEOAE levels. We conclude that visual attention does not significantly affect inner ear function.

パッシブチルドビームを用いた天井内冷却式放射空調の基礎検討 （第3報）CFDを用いた圧力損失特性と天井パネル表裏間移流量予測手法の検討

パッシブチルドビームを用いた天井内冷却式放射空調の基礎検討 （第3報）CFDを用いた圧力損失特性と天井パネル表裏間移流量予測手法の検討