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Control algorithms are the most crucial aspects in effective control of civil structures exposed to earthquake forces. Recently, adaptive intelligent control algorithms are evolving to be a viable substitute strategy for conventional model-based control algorithms. One of the most recent developments, known as the Brain Emotional Learning Based Intelligent Controller (BELBIC), has caught the attention of scientists as a model-free adaptive control system. It possesses appealing capabilities for dealing with nonlinearities and uncertainties in control frameworks. The modern semi-actively controlled civil structures have a highly uncertain and nonlinear nature following severe disturbances. As a result, these structures require real-time (online) robust control actions towards changing conditions, which the controllers with rigid settings cannot adapt. This study intends to overcome this issue in two ways: an online self-tuning brain emotional learning-based intelligent controller (ST-BELBIC) is formulated. Then its capabilities in improving the performance of cascaded controller in attenuating seismic vibrations of a three-story scaled building structure are validated. In this case, the central control unit BELBIC is based on sensory inputs (SI) and emotional cues (reward) signals. The main contribution of the proposed controller is a self-attuned version of the standard BELBIC that uses the benefits of a first-order Sugano fuzzy inference system (FIS) to adapt its parameters online. The proposed control methodology can be a promising model-free controller in terms of online tuning, simplicity of configuration, ease of applicability, less operational time, and neutralizing nonlinearities. The simulation affirms that the proposed controller compared with conventional LQR and intelligent Fuzzy tuned PID (FT-PID) controllers shows a superior performance regarding attenuating seismic responses of the building and can also improve the performance of cascaded FT-PID controller.

Electric field assisted combustion is an important means to improve fuel combustion efficiency. This paper conducts extensive research on flame characteristics under different forms and different application methods of electric fields, emission of soot particles and simulation status. Different flame parameter measurement methods will lead to different degrees of error, and perfect numerical simulation can make simple predictions on experimental data. Most of the current numerical simulations are in two dimensions, and it is necessary to develop a complete and accurate three-dimensional model to simulate and predict the characteristics of the flame under an electric field. The emission of soot particles is also affected by the electric field, and reasonable electric field parameters can greatly reduce the emission of soot particles. It is recommended to conduct centralized measurement of different fuels under the electric field under high pressure and temperature conditions, so as to be able to develop a wider and more accurate flame dynamics and chemical model under the electric field.

The hump-backed ginglymodian fish Kyphosichthys grandei, from the Anisian (Middle Triassic) of South China, is re-described. The revised description presents much previously unknown or misidentified anatomical information, such as the presence of a median gular plate; a short, broad, squarish rostral; two pairs of extrascapulars, of which the lateral one is fused with the parietal bone; parasphenoid having relatively large, dorsoposteriorly oriented ascending processes which articulate with the sphenotics; a complete row of scales bordering the body lobe; and supracleithrum with a concave facet for articulation with the posttemporal, etc. Taxonomical comparison clearly distinguishes Kyphosichthys from other known hump-backed ginglymodians – that is, Luoxiongichthys, Lophionotus, Semiolepis and Paralepidotus – and a potential stem-group ginglymodian Dapedium. A more comprehensive cladistic analysis of the Ginglymodi is conducted herein based on incorporation of more morphological characters and taxa, and r...

The influence of Cr doping for Mn on the structural, martensitic transformation and mechanical properties of Ni43Co5Mn44-xCrxSn8 (x = 0, 1.5, 3, 5, 6 and 6.5) alloys has been systematically investigated. The replacement of Mn by Cr changed the alloy microstructure from a single-phase martensite to a refined eutectic dual-phase microstructure consisting of a martensitic/austenitic matrix and a γ phase. The volume fraction of the γ phase increased progressively with increasing the Cr doping. The γ phase formation altered the composition and e/a ratio of the matrix phase. As a result, the martensitic temperatures and the entropy change of the transformation showed a decrease in these alloys. The Cr-doped eutectic Ni–Co–Mn–Sn alloy exhibited superior mechanical properties attributed to the well dispersed γ phase lamellar grains for effective crack retardation while retaining the metamagnetic phase transformation. The compressive strength and ductility of alloys are notably enhanced from 290 MPa to 1420 MPa and from 6.7% to 15.8% respectively with Cr doping from 0 at% to 6.5 at%.

This paper investigates the effects of post-deposition annealing on the evolution of phase structure and magnetic properties of magnetron sputtered Ni2FeGa/Si (001) thin films. The results revealed that the as-deposited film was partially crystallized in an fcc structure, i.e. [Formula: see text] phase. Crystallization of the amorphous structure into the [Formula: see text] phase was greatly encouraged following annealing at 723 K for 1 h. Annealing at higher temperatures for the same period triggered the formation of the bcc austenitic phase, which competed with the [Formula: see text] phase simultaneously for crystallization and grain growth. The evolution of phase structure and grain size also influenced the nanomechanical properties of the films according to the nanoindentation measurement. The film annealed at 873 K for 1 h showed high hardness and elastic modulus values of 11.1 GPa and 156 GPa. The [Formula: see text] phase showed stronger ferromagnetic characteristics relative to the bcc austenite due to the richer Fe content. This leads to the saturation magnetization to be maximized at 80 emu/g when annealed at 773 K for 1 h attributed to the enhanced film crystallinity and dominant volume fraction of [Formula: see text] phase in the thin film.

A hierarchical organization is common in most corporations, where some entities (objects) in the lower granulation level are subordinate to a single other entity (object) in the follow-on higher granulation level. During recent years, how to evaluate the objects in a group corporation has become a key strategic consideration. Therefore, this paper proposes a multi-granular hierarchical evaluation model for multiple criteria three sorting. In the model, the objects in a granulation level are assigned to three ordinal classes based on the theory of three-way decisions and the rating system, instead of accurately sorting them. Furthermore, the evaluation results from the previous granulation level are employed as one type of criteria in the follow-on granulation level, called the evaluation result criteria. Additionally, we propose a three-way TOPSIS (the Technique for Order of Preference by Similarity to Ideal Solution) method based on the characteristics of four types of criteria such as evaluation result criteria, benefit criteria, cost criteria and non-monotonic criteria. Besides, a pre-evaluation strategy is devised at each level inspired by the concept of "first impressions". Then, the final evaluation results are obtained by studying the qualitative evaluation results of pre-evaluation method and the quantitative evaluation results of three-way TOPSIS method. Finally, a numerical case study from an aluminium electrolysis production enterprise is illustrated to show its viability.

The hump-backed ginglymodian fish Kyphosichthys grandei, from the Anisian (Middle Triassic) of South China, is re-described. The revised description presents much previously unknown or misidentified anatomical information, such as the presence of a median gular plate; a short, broad, squarish rostral; two pairs of extrascapulars, of which the lateral one is fused with the parietal bone; parasphenoid having relatively large, dorsoposteriorly oriented ascending processes which articulate with the sphenotics; a complete row of scales bordering the body lobe; and supracleithrum with a concave facet for articulation with the posttemporal, etc. Taxonomical comparison clearly distinguishes Kyphosichthys from other known hump-backed ginglymodians – that is, Luoxiongichthys, Lophionotus, Semiolepis and Paralepidotus – and a potential stem-group ginglymodian Dapedium. A more comprehensive cladistic analysis of the Ginglymodi is conducted herein based on incorporation of more morphological characters and taxa, and rectification of the character states of some taxa used in previous analyses after re-description of Kyphosichthys grandei and better knowledge of Luoxiongichthys hyperdorsalis and Sangiorgioichthys sui based on our observations of specimens at the Geological Museum of Peking University, Beijing, China. The results of our analysis produce the most completely resolved and best-supported hypothesis for the monophyletic group Semionotiformes to date, and also support a new hypothesis that the Middle Triassic ginglymodians Luoxiongichthys, Sangiorgioichthys and Kyphosichthys form a monophyletic group at the base of the Ginglymodi, of which Kyphosichthys grandei is the sister group of Sangiorgioichthys sui. The new family Kyphosichthyidae is introduced. The present contribution supplements previous analyses of the Ginglymodi, especially for basal taxa and the clade Semionotiformes, and sheds new light on the origin and early diversification of the Ginglymodi. http://zoobank.org/urn:lsid:zoobank.org:pub:C8ACA263-8658-4A66-BFF9-99F6D5C84E91

Ammonium dinitramide (ADN) monopropellant is currently the most promising among all ‘green propellants’. In this paper, the decomposition and combustion process of liquid ADN-based ternary mixtures for propulsion are numerically studied. The R–R distribution model is used to study the initial boundary conditions of droplet distribution resulting from spray hit on a wire mesh based on PDA experiment. To simulate the heat-transfer characteristics between the gas–solid phases, a two-temperature porous medium model in a catalytic bed is used. An 11-species and 7-reactions chemistry model is used to study the catalytic and combustion processes. The final distribution of temperature, pressure, and other kinds of material component concentrations are obtained using the ADN thruster. The results of simulation conducted in the present study are well agree with previous experimental data, and the demonstration of the ADN thruster confirms that a good steady-state operation is achieved. The effects of spray inlet mass flux and porosity on monopropellant thruster performance are analyzed. The numerical results further show that a larger inlet mass flux results in better thruster performance and a catalytic bed porosity value of 0.5 can exhibit the best thruster performance. These findings can serve as a key reference for designing and testing non-toxic aerospace monopropellant thrusters.

In order to make full use of the air in the chamber, improve the mixing process, and reduce raw emissions and fuel consumption of diesel engine, we introduce the the concept of a new combustion system—the Double Swirl Combustion System (DSCS)—and introduce their hypothesis regarding the fuel-air mixing mechanism under DSCS. For validating the hypothesis, we made a series of actual diesel engine tests on DSCS. The engine tests were based on a 150-mm diesel engine, and both single-cylinder and multicylinder engines were tested under natural aspirated intake condition and boost intake condition. The results indicate that DSCS is suitable for improving a big bore diesel engine. Later, we made a series of spray experimental researches in order to investigate DSCS and whether it can be used under different load conditions. In addition, we investigated how the structural parameters of the DS chamber affect the fuel-air mixing process in order to establish an optimum design method of the DS chamber. In order to v...

Equations of motion of a structure under multidimensional seismic excitations are established based on dynamics and kinematics. The seismic excitations considered include two translational components in horizontal and a rotational component about vertical. The dynamics of a structure under such excitations is much more profound than usual expectations sated by conventional theories; the new presented equations reveal the remarkable difference in the acceleration calculations of the super structure. As the dynamic equations are the underlying model of a structure that governing their dynamic properties, the new equations provide a ground stone for theoretical analyses and engineering applications. Restoring forces and damping forces are also presented in detail. And a control algorithm for the nonlinear structure is introduced by applying a sate space control approach.

Based on the equivalent excitation method, the equivalent excitation load of the controlled system is constructed under random excitations, and then adopting the state space control theory, the responses of the controlled system are calculated. According to the equivalent excitation method, the statistical characteristics of the responses are determined to fulfill the random vibration analysis of the controlled system. The simulation analysis of a real building shows that the LQG controlled structural has remarkable control effect. And that prove the feasibility and effectiveness of the random vibration analysis for the controlled system.

Fuel-air mixing process is one crucial key to determine the performance of a diesel engine, and it is crucially determined by swirl within cylinder. For generating strong swirl within the cylinder, a new device named swirler has been propounded. In the present paper, four swirlers have been employed to experimentally study the performance on both the discharge capability and swirl generation capability. The steady flow test bench was employed to study the both capabilities in macro-level. Then, a water-flow model was employed to observe the flow motion within the cylinder via the tested swirlers. The results indicate that adopting swirler with a suitable configuration could generate strong swirl without remarkable discharge capability loss.

Ample intake charge and suitable intake flow motion can improve the combustion quality in diesel engine for it can promote the mixing process between air and fuel. But enough air charge is more difficult to reach for high blower engine. The stead flow test method under naturally aspirated condition is usually used to obtain the flow characteristics of engine intake port. But it may over-evaluate the flow ability when the intake port is used for a high blower engine. The characteristics of intake flow under supercharging condition have rarely been studied in past. Therefore, it is necessary to make study on the relation between the supercharging pressure and intake flow characteristics for supercharging diesel engine. In this paper, the authors have completed experiments under supercharging condition. The test data showed that the flow coefficient and swirl ratio is reduced with pressure difference increase between inlet and outlet of the port, and the flow coefficient and swirl ratio increases with intake pressure increase.

Swirl is an important flow pattern of air motion, it not only affects the fuel-air mixing and combustion processes in diesel engine, but also has a significant impact on heat transfer, combustion quality, and engine-raw emissions. For generating swirl efficiently, many researches have been performed, however, almost the methods have more or less crucial disadvantages. For overcoming these shortcomings and generating more efficient swirl during the intake process, the authors design a new device, swirler, to induce intake swirl in non-swirl intake port diesel engine. In this paper, the authors design four types of swirler including one straight-shaped swirler and three arc-shaped swirlers. In order to research the fundamental characteristics of swirler, the authors make series of experiments researches. The total researches can be divided into three stages: in the first stage, steady flow tests are carried for researching the swirl capability and the discharge capability of swirler from the macro-level, in the second stage, flow fields in the cylinder are measured by Particle Image Velocimetry (PIV) technique in the water analog tests for researching the swirl performance from the micro-level, at last stage, the tested swirler is installed on a certain type of actual diesel engine for studying whether swirler can improve the engine operation performance noticeably. The results show that this new device can induces intake swirl efficiently and can improve fuel economy at on an optimized swirl ratio.

Double swirl combustion system, which is abbreviated to DSCS, is a new combustion system. For its noticeable effect on improving the fuel-air mixing process and reducing raw emissions, it has been accepted and applied widely. Double swirl combustion chamber, as one of the most important components of the DSCS, plays an important role to affect the fuel-air mixing processes and the fuel-air mixture quality which controls the combustion processes. Hence, make the further researches on the DS combustion chamber and design an optimized DS combustion chamber is very necessary and important. However, there has no reports about the researches on the configuration parameters of DS chamber have been published. Therefore, the authors make the research on parametric design of DS combustion chamber, to find out the main configuration parameters of DS chamber, and then explore how those configuration parameters affect the performance of DS chamber. In this paper, the authors make analysis on the configuration structure detailedly, and determine the crucial configuration parameters of DS chamber, and then, the authors make series of simulation researches on those parameters to reveal their effect rules, and indicate the design direction of DS chamber based on those results.

Eight almost complete medium-large sized (about 33 cm in s.l.) fossil fishes, belonging to the family Colobodontidae, are described from the Pelsonian (Anisian, Middle Triassic) of South China. Their cranial and postcranial features fit those of the genus Colobodus Agassiz, 1844 from the western Tethys. However, they are older than the previously known Colobodus species and, furthermore, they come far from the western Tethys, where most colobodontids have been found so far. The significance of our new findings, beyond the erection of a new species, lies in the fact that they are the first definite record of Colobodus outside the western Tethyan faunal province, and represent the oldest unequivocal colobodontids worldwide, as well as suggest that they could have originated in the East rather than the western Tethys, as previously thought., Rivista italiana di Paleontologia e Stratigrafia, Vol 114, No 3