Secondary Subsystems Research Articles

ВІЗУАЛЬНА МАТЕМАТИЧНА МОДЕЛЬ ЕЛЕКТРОМЕХАНІЧНОЇ СИСТЕМИ ВІТРОЕНЕРГЕТИЧНОЇ УСТАНОВКИ З АЕРОДИНАМІЧНИМ МУЛЬТИПЛІКУВАННЯМ

Building a visual mathematical model of the electromechanical wind power system with aerodynamic multiplication. In the process of constructing a visual mathematical model of the electromechanical system of wind turbines with aerodynamic multiplication, a mathematical apparatus for describing the system in local mean values of variables was used. Verification of the mathematical model was carried out in the MATLAB Simulink program. A visual mathematical model of the electromechanical system of wind turbines with aerodynamic multiplication is developed, which includes mechanical power losses on the shaft of the primary wind turbine. The visual mathematical model of the electromechanical system of wind power plant with aerodynamic multiplication taking into account the mechanical power losses on the shaft of the primary wind turbine with uneven distribution of power flows between the three secondary aeromechanical subsystems was proposed for the first time.

Superconducting Magnet Power Supply and Hard-Wired Quench Protection at Jefferson Lab for 12 GeV Upgrade

The superconducting magnet system in Hall B being designed and built as part of the Jefferson Lab 12 GeV upgrade requires powering two conduction cooled superconducting magnets-a torus and a solenoid. The torus magnet is designed to operate at 3770 A and the solenoid at 2416 A. Failure modes and effects analysis determined that voltage level thresholds and dump switch operation for magnet protection should be tested and analyzed before incorporating into the system. The designs of the quench protection and voltage tap subsystems were driven by the requirement to use a primary hard-wired quench detection subsystem together with a secondary programmable logic controller (PLC)-based protection. Parallel path voltage taps feed both the primary and the secondary quench protection subsystems. The PLC-based secondary protection is deployed as a backup for the hard-wired quench detection subsystem and also acts directly on the dump switch. We describe a series of tests and modifications carried out on the magnet power supply and the quench protection system to ensure that the superconducting magnet is protected against all fault scenarios.

SPECKLE INTERFEROMETRY OF SECONDARY COMPONENTS IN NEARBY VISUAL BINARIES*

ABSTRACT Statistical characterization of secondary subsystems in binaries helps to distinguish between various scenarios of multiple-star formation. The Differential Speckle Survey Instrument was used at the Gemini-N telescope for several hours in 2015 July to probe the binarity of 25 secondary components in nearby solar-type binaries. Six new subsystems were resolved, with meaningful detection limits for the remaining targets. The large incidence of secondary subsystems agrees with other similar studies. The newly resolved subsystem HIP 115417 Ba,Bb causes deviations in the observed motion of the outer binary from which an astrometric orbit of Ba,Bb with a period of 117 years is deduced.

Seismic response of subsystems in irregular buildings

The component-mode synthesis method is applied to investigate the seismic response of secondary subsystems multi-connected to primary structures with irregularities. The proposed approach is more accurate than the cascade approximation, which is often used in the design practice, as the primary–secondary dynamic interaction is considered through the modes of vibration of the two components. The results of parametric analyses on a representative case study reveal similar trends in the displacements of the two components for mass irregularities in elevation, while stiffness irregularities in plan can result in significant torsional motion in both components, with the effects in terms of absolute accelerations being in general larger than those associated with the lateral drifts. This suggests that dynamic analyses with the component-mode synthesis method are particularly indicated for the seismic assessment of acceleration-sensitive secondary subsystems.

Architecture as system: A study of housing systems evolution

Understanding architecture via the concept of system came after numerous, rapid and different developments upon all aspects of architecture, especially since the last third of past century till the present day.Some theories characterized architecture as the complex whole that based on the different relationships and interrelationships with different sciences, besides of the multiplicity and independency of internal components, it should be assigned into the world of integrated system.This study attempts to explain the phenomenon of architecture through the concept of (system), in order to include both its cognitive (the subject) - which is potential, and realistic presence (the object) -which is explicit. This study tries to explore both sides of the concept, in order to understand the architectural system -in one hand and determining its components -in the other hand.To find out how these systems which have been developed via some housing projects, as an integrated system; comprised by secondary sub-systems with clear limits, within the total system of the housing project. This study follows the inductive and descriptive approach as a methodology, depending on the related literatures and applied available theories in residential projects during different periods of time.The study aims to identify the systems and levels, set to reach a comprehensive understanding of the architectural system in general, and the evolutions of housing systems, in particular, benefiting from the rapid developments of this architectural style (Housing), which have been seen in many various levels too.

A SURVEY OF THE HIGH ORDER MULTIPLICITY OF NEARBY SOLAR-TYPE BINARY STARS WITH Robo-AO

We conducted a survey of nearby binary systems composed of main sequence stars of spectral types F and G in order to improve our understanding of the hierarchical nature of multiple star systems. Using Robo-AO, the first robotic adaptive optics instrument, we collected high angular resolution images with deep and well-defined detection limits in the SDSS $i'$ band. A total of 695 components belonging to 595 systems were observed. We prioritized observations of faint secondary components with separations over $10''$ to quantify the still poorly constrained frequency of their sub-systems. Of the 214 secondaries observed, 39 contain such subsystems; 19 of those were discovered with Robo-AO. The selection-corrected frequency of secondary sub-systems with periods from $10^{3.5}$ to $10^5$ days is 0.12$\pm$0.03, the same as the frequency of such companions to the primary. Half of the secondary pairs belong to quadruple systems where the primary is also a close pair, showing that the presence of sub-systems in both components of the outer binary is correlated. The relatively large abundance of 2+2 quadruple systems is a new finding, and will require more exploration of the formation mechanism of multiple star systems. We also targeted close binaries with periods less than 100~yr, searching for their distant tertiary components, and discovered 17 certain and 2 potential new triples. In a sub-sample of 241 close binaries, 71 have additional outer companions. The overall frequency of tertiary components is not enhanced, compared to all (non-binary) targets, but in the range of outer periods from $10^6$ to $10^{7.5}$ days (separations on the order of 500~AU), the frequency of tertiary components is 0.16$\pm$0.03, exceeding by almost a factor of two the frequency of similar systems among all targets (0.09).

IMAGING SURVEY OF SUBSYSTEMS IN SECONDARY COMPONENTS TO NEARBY SOUTHERN DWARFS

To improve the statistics of hierarchical multiplicity, secondary components of wide nearby binaries with solar-type primaries were surveyed at the SOAR telescope for evaluating the frequency of subsystems. Images of 17 faint secondaries were obtained with the SOAR Adaptive Module that improved the seeing; one new 0.2" binary was detected. For all targets, photometry in the g', i', z' bands is given. Another 46 secondaries were observed by speckle interferometry, resolving 7 close subsystems. Adding literature data, the binarity of 95 secondary components is evaluated. We found that the detection-corrected frequency of secondary subsystems with periods in the well-surveyed range from 10^3 to 10^5 days is 0.21+-0.06, same as the normal frequency of such binaries among solar-type stars, 0.18. This indicates that wide binaries are unlikely to be produced by dynamical evolution of N-body systems, but are rather formed by fragmentation.

Physiologic and metagenomic attributes of the rhodoliths forming the largest CaCO3 bed in the South Atlantic Ocean

Rhodoliths are free-living coralline algae (Rhodophyta, Corallinales) that are ecologically important for the functioning of marine environments. They form extensive beds distributed worldwide, providing a habitat and nursery for benthic organisms and space for fisheries, and are an important source of calcium carbonate. The Abrolhos Bank, off eastern Brazil, harbors the world's largest continuous rhodolith bed (of ∼21,000 km(2)) and has one of the largest marine CaCO3 deposits (producing 25 megatons of CaCO3 per year). Nevertheless, there is a lack of information about the microbial diversity, photosynthetic potential and ecological interactions within the rhodolith holobiont. Herein, we performed an ecophysiologic and metagenomic analysis of the Abrolhos rhodoliths to understand their microbial composition and functional components. Rhodoliths contained a specific microbiome that displayed a significant enrichment in aerobic ammonia-oxidizing betaproteobacteria and dissimilative sulfate-reducing deltaproteobacteria. We also observed a significant contribution of bacterial guilds (that is, photolithoautotrophs, anaerobic heterotrophs, sulfide oxidizers, anoxygenic phototrophs and methanogens) in the rhodolith metagenome, suggested to have important roles in biomineralization. The increased hits in aromatic compounds, fatty acid and secondary metabolism subsystems hint at an important chemically mediated interaction in which a functional job partition among eukaryal, archaeal and bacterial groups allows the rhodolith holobiont to thrive in the global ocean. High rates of photosynthesis were measured for Abrolhos rhodoliths (52.16 μmol carbon m(-2 )s(-1)), allowing the entire Abrolhos rhodolith bed to produce 5.65 × 10(5) tons C per day. This estimate illustrates the great importance of the Abrolhos rhodolith beds for dissolved carbon production in the South Atlantic Ocean.

Availability of k-out-of-n: F Secondary Subsystem with General Repair Time Distribution

In this paper we study the steady state availability of main k-out-of-n: F and secondary subsystems having general repair time distribution. When more than k units of main subsystem fail, then the main subsystem shuts off the secondary subsystem. The life time distributions of the main units and that of secondary subsystem are exponentially distributed. A repair facility having single repairman is facilitated to restore the failed unit. Failure of the main unit shuts off the operation of secondary subsystem, but not vice versa. Failure of the main unit or the secondary subsystem initiates the system shut down. The steady state availability is obtained by solving the linear ordinary differential equations governing the model by using supplementary variable technique.

Study on Environmental Materials with Analysis of the Hydraulic Connection Between Downtown and East and West Suburbs in Jinan, Shandong Province of China

The recognize of hydrogeological conditions is not clear, and there has always been states of dry up in Jinan spring. This paper divides jinan monoclinic structure into three primary ground water systems, and three secondary karst water subsystems based on the groundwater system theory. On that basis, reveal the recharge source of Jinan springs through the analysis of regional aquifer medium and hydrodynamic characteristic, further confirm that the hydraulic connection of western suburb is better close with downtown than that of eastern suburb by regression analysis method, so the recharge well can be designed and allocated in western suburb to recharge groundwater.This paper introduces inverted filter's materials needed by recharge well such as quartz sand and limestone, as well as advantages and disadvantages of them. These conclusions provide scientific basis for spring protection and the mining of karst water with high quality.

Nonsingular decoupled terminal sliding-mode control for a class of fourth-order nonlinear systems

This paper presents a nonsingular decoupled terminal sliding mode control (NDTSMC) method for a class of fourth-order nonlinear systems. First, the nonlinear fourth-order system is decoupled into two second-order subsystems which are referred to as the primary and secondary subsystems. The sliding surface of each subsystem was designed by utilizing time-varying coefficients which are computed by linear functions derived from the input–output mapping of the one-dimensional fuzzy rule base. Then, the control target of the secondary subsystem was embedded to the primary subsystem by the help of an intermediate signal. Thereafter, a nonsingular terminal sliding mode control (NTSMC) method was utilized to make both subsystems converge to their equilibrium points in finite time. The simulation results on the inverted pendulum system are given to show the effectiveness of the proposed method. It is seen that the proposed method exhibits a considerable improvement in terms of a faster dynamic response and lower IAE and ITAE values as compared with the existing decoupled control methods.

Projection of the liquidus surface of the Co – Sb – Pb ternary intermetallic system

Methods of physicochemical analysis are used to plot the phase diagram of the Co0.745Sb0.255 – Sb0.8Pb0.2 section and the projection of the liquidus surface of the Co – Sb – Pb system. Triangulation secants are used to cut the system into two secondary ternary subsystems consisting of six fields of primary crystallization of phases and a splitting field. The boundaries of monotectic transformations, the development of single-variant processes, and the coordinates of nonvariant equilibrium compositions are determined.

Information Theory for Generation of Accelerograms Associated with Shock Response Spectra

In structural dynamics, the specification of the transient loads applied to equipment (or to secondary subsystems) consists of a given shock response spectrum (SRS). The transient dynamical analysis of such equipment is performed using a computational nonlinear dynamical model. A generator of accelerograms satisfying the given SRS is then required. Information theory is used to solve this challenging inverse problem that has been looked at by others but not in the way presented. The maximum entropy principle is used to construct the probability distribution of the nonstationary stochastic process for which the available information is constituted of the mean SRS and additional information on the variance. A random generator of independent realizations of the nonstationary stochastic process is developed using a new algorithm based on the stochastic analysis. The method presented is validated with an example.

Ecological Interface Design in the Nuclear Domain: An Application to the Secondary Subsystems of a Boiling Water Reactor Plant Simulator

Accident investigations have revealed that unanticipated events are often precursors of major accidents. Unfortunately, conventional approaches to interface design for complex systems do not explicitly support problem solving during unanticipated events. Ecological Interface Design (EID) is a theoretical framework for designing computer interfaces that explicitly aims to support worker adaptation, especially during unanticipated events, leading to more robust user interfaces. However, limited verification and validation research in representative settings is impeding the adoption of the EID framework in the nuclear domain. This article presents an example by applying EID to the secondary side of a boiling water reactor plant simulator. The interface designers constructed abstraction hierarchy, causal, and part-whole models to acquire pertinent knowledge of the work domain and designed five ecological displays to represent the plant processes. These displays are analytically shown to contain visualization properties that could support monitoring and diagnosing unanticipated events in accordance to the claims of the EID framework. The analytical evaluation of the visualization features of the displays also illustrates that the EID framework could be applied to improve current verification practice. A companion article reports an empirical evaluation of these ecological displays to validate whether these properties could enhance operator performance.

Ecological Interface Design in the Nuclear Domain: An Empirical Evaluation of Ecological Displays for the Secondary Subsystems of a Boiling Water Reactor Plant Simulator

Laboratory studies have shown that ecological interfaces can enhance operator performance in process control. However, limited verification and validation studies in representative settings are impeding the adoption of the Ecological Interface Design (EID) framework in the nuclear domain. A companion article presents an application of EID to the secondary side of a boiling water reactor plant simulator, demonstrating that the framework can lead to display features and verification criteria relevant to supporting operators in both anticipated and unanticipated situations. This article presents an empirical study as a first step towards the validation of EID in the nuclear domain. The results suggest that ecological displays have a marked advantage in supporting operator performance during monitoring for unanticipated events as compared to mimic-based displays. The ecological displays did not support operator performance differently for other types of tasks. This study provides supporting or validation evidence that EID is effective at a scale and level of complexity that is representative of nuclear power plant operations. The implications for introducing ecological displays into NPP control rooms are discussed.

Integrating Subsystems and Engine System Assessments

In the past, system and subsystem level assessments for propulsion systems have been a long and drawn out serial process, typically taking several months to a year or more. Data exchange from one subsystem group to the next was a manual process. This was particularly the case when different computer platforms were being utilized to run the models. Each group would optimize their particular subsystem as a separate entity. There were no approaches available to facilitate the evaluation of how a particular subsystem, when combined with the engine, would impact the overall integrated system. The availability of tools to facilitate direct interface of the various subsystem models with engine performance decks was not available. As a result, the lead times for various iterations were such that not all of the groups were even working on the same configuration. Fortunately, software technology has been evolving, and the ability to integrate models is now becoming available. This paper describes work in progress of an innovative methodology for high-level integration of complex flight systems. This new approach will facilitate rapid integration and optimization of propulsion and secondary subsystems in a truly concurrent manner, providing capability for top-level evaluation of complex and highly integrated flight system architectures

Trends in modeling of structural-acoustics systems with structural complexity in low- and medium-frequency ranges

This paper gives a comprehensive survey of a theoretical approach for predicting the frequency response functions of general complex structural acoustics systems (CSAS) in the low- and medium-frequency ranges. For such a CSAS, the complex structure is made of a master structure coupled with internal substructures presenting structural complexity and corresponding to a large number of secondary subsystems, such as equipment units or internal secondary structures, attached to the master structure. The master structure is a general 3-D dissipative structure with an arbitrary bounded geometry and is made of an anisotropic, inhomogeneous, viscoelastic medium. This complex structure is coupled with an external acoustic fluid via the master structure. The approach is based on the use of fuzzy structure theory, introduced by the author in 1985, including recent developments concerning identification of the fuzzy substructure model parameters. This theory allows the effects of the internal structural complexity on the master structure to be modeled. In addition, the construction of an intrinsic reduced model of the frequency response functions of this CSAS adapted to the medium-frequency range (recently proposed by the author) is presented, which allows simplifications in the calculation of the responses to any deterministic or random excitations.

Availability of the system with general repair time distributions and shut-off rules

A model which has main and secondary subsystems subject to shut-off rules is considered. In this model, the system has a single repair facility. The repair discipline that the main subsystem has the pre-emptive repeat priority is considered. Constant failure rate and general repair time distributions are assumed. The system availability is obtained by using the linear ordinary differential equation method and supplementary variable technique.

Availability for 2/n: F and secondary subsystems with general repair-time distributions and shut-off rules

The model which main 2/n: F and secondary subsystems subject to shut-off rules is considered. In this model, the system has single repair facility. The repair discipline that the main subsystem has the preemptive repeat priority is considered. Constant failure rate and general repair-time distribution are assumed. The system availability is obtained by using linear ordinary differential equation method and supplymentary variable technique.

Availability and reliability of the system with pre-emptive priorities and shut-off rules

A model involving main standby redundancy and secondary subsystems having pre-emptive repeat priorities is considered. If the secondary subsystem fails when the main subsystem is operating with one functioning unit and one failed unit, then the secondary subsystem starts to be repaired (pre-emptive priority). If both main and secondary subsystems are inoperable, then the main subsystem has high priority for repair. In this model, we obtained the system availability, the mean inter-occurrence shut-off time and steady-state probability that the system is under shut-off by the technique of the Markov renewal process. We also obtained the system reliability by using the Markov chain.