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The purpose of this paper is to propose an attitude control algorithm for spacecraft with geometric constraints.

The geometric constraint is reformulated as a quadratic form when quaternion is used as attitude parameter, then the constraint is proved to be nonconvex and is further transformed to a convex one. By designing a new constraint formulation to satisfy the real constraint in the predictive horizon, the attitude control problem is reshaped to a convex planning problem which is based on receding horizon control.

The proposed algorithm is more effective in handling geometric constraints than previous research which used single step planning control.

With novel improvements to current methods for steering spacecraft from one attitude to another with geometric constraints, great attitude maneuver path can be achieved to protect instruments and meanwhile satisfy mission requirements.

The attitude control algorithm in this paper is designed especially for the satisfaction of geometric constraints in the process of attitude maneuver of spacecraft. By the application of this algorithm, the security of certain optical instruments, which is critical in an autonomous system, can be further assured.

This paper aims to propose and establish a set of new benchmark models to investigate and confidently validate the modeling and prediction of total stray-field loss inside magnetic and non-magnetic components under harmonics-direct current (HDC) hybrid excitations. As a new member-set (P21^e) of the testing electromagnetic analysis methods Problem 21 Family, the focus is on efficient analysis methods and accurate material property modeling under complex excitations.

This P21^e-based benchmarking covers the design of new benchmark models with magnetic flux compensation, the establishment of a new benchmark measurement system with HDC hybrid excitation, the formulation of the testing program (such as defined Cases I–V) and the measurement and prediction of material properties under HDC hybrid excitations, to test electromagnetic analysis methods and finite element (FE) computation models and investigate the electromagnetic behavior of typical magnetic and electromagnetic shields in electrical equipment.

The updated Problem 21 Family (V.2021) can now be used to investigate and validate the total power loss and the different shielding performance of magnetic and electromagnetic shields under various HDC hybrid excitations, including the different spatial distributions of the same excitation parameters. The new member-set (P21^e) with magnetic flux compensation can experimentally determine the total power loss inside the load-component, which helps to validate the numerical modeling and simulation with confidence. The additional iron loss inside the laminated sheets caused by the magnetic flux normal to the laminations must be correctly modeled and predicted during the design and analysis. It is also observed that the magnetic properties (B27R090) measured in the rolling and transverse directions with different direct current (DC) biasing magnetic field are quite different from each other.

The future benchmarking target is to study the effects of stronger HDC hybrid excitations on the internal loss behavior and the microstructure of magnetic load components.

This paper proposes a new extension of Problem 21 Family (1993–2021) with the upgraded excitation, involving multi-harmonics and DC bias. The alternating current (AC) and DC excitation can be applied at the two sides of the model’s load-component to avoid the adverse impact on the AC and DC power supply and investigate the effect of different AC and DC hybrid patterns on the total loss inside the load-component. The overall effectiveness of numerical modeling and simulation is highlighted and achieved via combining the efficient electromagnetic analysis methods and solvers, the reliable material property modeling and prediction under complex excitations and the precise FE computation model using partition processing. The outcome of this project will be beneficial to large-scale and high-performance numerical modeling.

This paper aims to investigate an efficient approach to model the electromagnetic behaviors and predict stray-field loss inside the magnetic steel plate under 3D harmonic magnetization conditions so as to effectively prevent the structural components from local overheating and insulation damage in electromagnetic devices.

An experimental setup is applied to measure all the magnetic properties of magnetic steel plate under harmonic excitations with different frequencies and phase angles. The measurement and numerical simulation are carried out based on the updated TEAM Problem 21 Model B+ (P210-B+), under the 3D harmonic magnetization conditions. An improved method to evaluate the stray-field loss is proposed, and harmonic flux distribution in the structural components is analyzed.

The influence of the harmonic order and phase angle on the stray-field loss in magnetic steel components are noteworthy. Based on the engineering-oriented benchmark models, the variations of stray-field losses and magnetic field distribution inside the magnetic components under harmonic magnetization conditions are presented and analyzed in detail.

The capacity of the multi-function harmonic source, used in this work, was not large enough, which limits the magnetization level. Up to now, further improvements to increase the harmonic source capacity and investigations of the electromagnetic behaviors of magnetic steel components under multi-harmonic and DC-AC hybrid excitations are in progress.

To accurately predict the stray-field loss in magnetic steel plate, the improved method based on the combination of magnetic measurement and numerical simulation is proposed. The effects of the frequency and phase angle on the stray-field loss are analyzed.

The purpose of this study is to provide effective and environmental-friendly corrosion inhibitors derived from graphene oxide for Q235 steel.

Nontoxic and environment-friendly 4-aminobenzoic acid was used to functionalize graphene oxide via amidation and diazotization. The obtained amidation 4-aminobenzoic acid functionalized graphene oxide (PAGO) and diazotization 4-aminobenzoic acid functionalized graphene oxide (PDGO) were characterized by FTIR, Raman and TEM, while the inhibition efficiencies were analyzed by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP). Furthermore, theoretical inhibition efficiencies were investigated by density functional theory (DFT) approach.

At a concentration of 40 ppm, the maximum inhibition efficiency of PAGO and PDGO were 97.90% and 96.72% in EIS measurement, respectively, which were in accordance with PDP data. Moreover, experimental results were supported by DFT-based quantum chemical calculation.

Environmental-friendly PAGO and PDGO were synthesized successfully. The synthetic inhibitors exhibited excellent inhibition efficiencies in EIS and PDP measurements. Furthermore, a computational study using DFT supported the trend that PAGO was better inhibitor than PDGO.

This paper aims to introduce the decomposed harmonic balance finite element method (HBFEM) to decrease the memory requirement in large‐scale computation of the DC‐biasing magnetic field. Harmonic analysis of the flux density and flux distribution was carried out to investigate the DC biased problem in a laminated core model (LCM).

Based on the DC bias test on a LCM, the decomposed HBFEM is applied to accurately calculate the DC‐biasing magnetic field. External electric circuits are coupled with the magnetic field in the harmonic domain. The reluctivity matrix is decomposed and the block Gauss‐Seidel algorithm solves each harmonic solution of magnetic field and exciting current sequentially.

The calculated exciting currents and flux density are compared with that obtained from measurement and time domain finite element analysis, respectively, which demonstrates consistency. The DC bias leads to the significant saturation of the magnetic core and serious distortion of the exciting current. The flux density varies nonlinearly with DC bias excitation.

The harmonic balance method is only applicable in solving the steady state magnetic field. Future improvements in the method are necessary in order to manage the hysteresis effects in magnetic material.

The proposed method to solve the DC biased problem significantly reduces the memory requirement compared to the conventional HBFEM. The decomposed harmonic balance equations are solved efficiently by the block Gauss‐Seidel algorithm combined with the relaxation iterative scheme. An investigation on DC bias phenomena is carried out through the harmonic solution of the magnetic field. The decomposed HBFEM can also be applied to solve 3‐D DC‐biasing magnetic field and eddy current nonlinear problems in a practical power transformer.

Previous studies have considered customers' psychological responses to intelligent retail technology adoption, but have not considered how technology integration systems could promote the relationship between retailers and consumers. Based on the Stimulus–Organism–Response framework, this paper proposes a customer engagement model in a fully intelligent retail environment. The concept of the quality of intelligent experience is constructed from the perspective of customer experience, and the effect of the mechanism of smart retail on the customer engagement relationship is discussed.

Using two surveys, this study analyzes 201 (in study 1) and 321 (in study 2) questionnaires by using structural equation model in partial least square software.

The analysis shows that the human–machine interaction, intelligent systems and the product content of the quality intelligent experience significantly impact customer engagement on smart retail.

This research was designed for general retail products, without distinguishing between different product types. Thus, it did not consider the moderating effect of product types.

The findings enrich the intelligent retail technology field and provide operable guidance to help smart retailers improve customer relations.

This paper proposes a customer engagement model to describe how technology integration systems promote the relationship between retailers and consumers.

Marketers recognize that the internet is crucial in the lives of consumers; thus, they invest money on online advertisements. Using multiple online media primarily influences the message acceptance of consumers. The synergistic effect of online multimedia relies on form, content, and sources of information, and time. The paper aims to discuss these issues.

A model that reflects the influence of the characteristics of online multimedia on message response through message acceptance is established based on theories of information persuasion, encoding variability, and multiple-source assumption. Based on a survey of 411 online media users, the study applies partial least-squares regression to test the research model.

The results show that variety of forms, complementary of contents, diversity of sources, and time interval influence message response via message strength. Complementary of contents and diversity of sources affect message response via perceived credibility. Synergy type moderates the relationship between variety of forms and perceived credibility and between diversity of sources and perceived credibility.

The current study mainly tests the effect of these characteristics on message response and the moderating effect of synergy type. Future research can examine the effect of these characteristics on information seeking and consumption behavior and the moderating effect of the cognitive mode of consumers.

This study provides insight into the characteristics of synergy and contributes to the literature on integrated marketing communication. The results provide guidance for practitioners to effectively plan online multimedia practices.

This study explored the influence of the characteristics of online media synergy on message response through message acceptance. The study also discussed the moderating effect of the type of online multimedia synergy.

This study aims to investigate the influence of soy protein isolate hydrolysates (SPIH) obtained using 4 h hydrolysis under 200 MPa on proximate composition, cooking loss, textural properties, color, water distribution, microstructure, thiobarbituric acid reactive substance (TBARS) value and carbonyl and sulfhydryl contents of emulsion sausages.

Sausages with SPIHs at four concentrations (0, 1.0, 2.0 and 3.0%) were prepared, and the sausage with 0.01% butylated hydroxyanisole (BHA) was used as a positive control. Some sausages were selected for the analyses of quality characteristics and microcosmic properties. Other sausages were stored under 4 °C for 0, 7, 14, 21 and 28 days to investigate the oxidative stability.

The addition of SPIHs at various levels (0–3.0%) or 0.01% BHA did not affect the proximate composition (protein, fat and ash) of emulsion sausages. The addition of 2.0% SPIH decreased cooking loss and increased moisture content, hardness, springiness, chewiness, resilience and L* value, compared to the sausages without SPIH and with 0.01% BHA (p < 0.05). Furthermore, low-field nuclear magnetic resonance results suggested that sausages with 2.0% SPIH had the shortest T2 relaxation time. In addition, 2.0% SPIH and 0.01% BHA could inhibit the oxidation of emulsion sausages when compared with the sample without SPIH (p < 0.05). Moreover, there were no differences between sausages with 2.0% SPIH and 0.01% BHA (p > 0.05).

These findings confirmed that the 2.0% SPIH obtained under 200 MPa can be used as a natural additive to improve quality properties and antioxidant potential of emulsion sausages during storage.

The purpose of this paper is to develop a preliminary model of instructional leadership in the Chinese educational context and explore the ways in which Chinese school principals locate their instructional-leadership practices in response to traditional expectations and the requirements of recent reforms.

In-depth interviews were conducted with 22 selected primary school principals in Shenzhen and Guangzhou. A qualitative analysis was conducted to categorize the major leadership practices enacted by these principals.

An initial model of instructional leadership in China with six major dimensions is constructed. The paper also illustrates and elaborates on three dimensions with the greatest context-specific meanings for Chinese principals.

The paper explores the ways in which Chinese principals enact their instructional leadership in a context in which “the west wind meets the east wind”; that is, when they are required to accommodate both imported reform initiatives and traditional expectations. The paper contributes to the sparse existing research on principals’ instructional leadership in non-western cultural and social contexts.

The purpose of this paper is to review the current research on theoretical foundations and applications for CPS from 2017 to 2019 including the applications in library.

This paper is designed in six parts as Introduction, Literature review, Theoretical foundations of CPS, Applications of CPS, CPS’s application in library and Conclusion. The authors review 70 papers and classify them as the above six parts. The authors collected 70 papers from 2017 to 2019 in the academic databases.

This paper reviews 70 papers regarding theoretical foundations and applications for CPS from 2017 to 2019 in the academic databases aiming to provide scholars and practitioners with a comprehensive overview. The contents of the papers in each research category are summarized from theoretical foundations and applications including the CPS applications in library.

A main contribution of this review paper is that it summarizes the current state-of-the-art theoretical foundations and applications for CPS and in libraries systematically.