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Purpose The purpose of this paper is to analyse privacy and interaction preferences in the social dimension of individual learning students and how the spatial configuration affects individual learners’ choices of learning spaces. Design/methodology/approach This empirical survey study was conducted in an Australian university’s informal learning spaces. Space syntax theories are applied to construct a four-quadrant theoretical framework. Findings The research findings indicate that based on the differences between students in their individual characteristics, there are significant differences in their needs for privacy and interaction. This study reveals that the spatial configuration affects individual learners’ choices of learning spaces. Originality/value This study could assist universities in providing students with more effective and diverse informal learning spaces.

With the development of distributed fiber optic acoustic sensing technology in the field of borehole seismic surveys, more and more oil fields choose to pre-install fiber optics in the well in advance for borehole seismic data acquisition or fluid detection. In 2022, ADNOC completed the world’s first multi-well DAS VSP and OBN joint acquisition survey in the Persian Gulf, with the fiber placed outside the tubing, relying on the offshore high-density OBN acquisition survey, completing a total of 13 wells for DAS VSP acquisition. The DAS VSP raw data spacing interval is 1 m, the sampling interval is 1 ms, and the offshore air guns are staggered at a density of 25 m × 25 m. This study will focus on the determination of multi-well DAS VSP data acquisition area, data analysis for different Gauge Length, and raw data quality control.

Under the dual constraints of industrialization and digitalization, the building skin and structure are further integrated to form standardized units to meet the requirements of architectural performance, industrial prefabrication and “complexity” aesthetic characteristics. The complex and diverse forms of today's building skin hide profound mathematical logic relations and operation rules of form generation. Crystallographic group with regular symmetry and the operation principles reflected by it is one of the most important rules and methods of form and pattern processing in skin design. The study of the mural symbols in ancient Egypt, the murals in the Alhambra, the manuscripts of Escher and the window lattice in ancient Chinese architecture profoundly reflects the basic operation principle of crystal group in shaping the skin form of architecture. Abundant and diverse architectural skin forms can be formed through the operation of symmetry group on basic graphic units. On the basis of clarifying the basic principle of crystal group action, the operation matrix of crystallographic symmetry group can be transformed into parameterized operation steps through programming language for visual operation, and then the skin form with high complexity and leap dimension can be generated by geometric algorithm, and the design method of building skin generation based on crystallographic group is constructed. In the selection of operation form, combined with the calculation of building performance and structure, the construction skin can be used in practical engineering is generated. Based on crystallographic group operation, the unifications of building skin and the classification simplification of components can meet the requirements of modular and unifications design in the process of building industrialization, and meet the requirements of current building industrialization and digitization. It has great research significance and value in the aspects of design and construction efficiency and material economic cost.

Nowadays problems such as insufficient rural residents’ participation and homogeneous design in the unified construction mode of rural housing in the north China plain mean that residents are increasingly unable to obtain satisfactory housing. The objective of this paper is to provide a shape grammar-based method which can analyze the design vocabularies and generate new solutions to rural housing. Based on a field survey of 56 villages in Shandong Province is located on the North China Plain, the elements of the shape and layout of traditional housing and well-off housing were summarized, and dwelling rules (Stage 1) and room rules (Stage 2) were defined. After that, the rules with the demands of rural residents (derived from Chinese rural family life cycle model and the rural resident types of China) were matched to define transformation rules (Stage 3). Finally, the operability and rationality of this method were verified, with the finding that shape grammar can effectively solve the problem of matching customized mass housing design with differentiated demands from users.

In this paper, a novel double-rotor hybrid excited axial switched-flux permanent magnet (DRHE-ASFPM) machine incorporating the advantages of the axial switched-flux permanent magnet (PM) machine and wound field synchronous machine is investigated. Similar to the switched-flux PM machine, there is a large undesired cogging torque in the DRHE-ASFPM machine because of high air-gap density and strong flux-focusing effect. This paper presents and compares three cogging torque reduction techniques in the DRHE-ASFPM machine, including stator/rotor teeth notching, stator slot chamfering, as well as stator slot chamfering and teeth notching (SCTN). The analytical expression of the cogging torque is derived and three methods are analyzed and compared in detail. As verified by 3-D finite element (FE) method, the SCTN technique can effectively reduce the cogging torque extremely, but slightly decrease the output torque under both PM and hybrid excitation modes. Finally, an optimized prototype machine with SCTN structure is manufactured, and the experiment is performed to validate the FE predicted results.

This paper proposes a novel axial flux rotor consequent-pole permanent magnet (AFRCPPM) machine with improved torque density. The key is to place the PMs between the adjacent rotor teeth with switched-flux feature compared to the stator permanent magnet (PM) dual-stator axial switched-flux PM (DS-ASFPM) machine. This will be able to obtain simple stator structure, high power density and large torque output capability. In the following paper, the topology, operating principle and winding configuration are analyzed in detail. According to the theoretical derivation, the major parameters of the AFRCPPM machine are acquired. Based on 3-D finite-element (FE) method, the electromagnetic performance of the AFRCPPM machine and DS-ASFPM machine is comparatively investigated to evaluate their characteristics. The FE-predicted results indicate that the AFRCPPM machine exhibits simple stator structure, sinusoidal back-EMF and high power/torque density. Moreover, under the same armature current, the AFRCPPM machine has larger output torque compared to the DS-ASFPM machine. Hence, it has a good prospect in electric vehicle (EV) or hybrid EV.

In this paper, a novel 6-stator-pole double-rotor hybrid excited axial switched-flux permanent magnet (DR-HEASFPM) machine is proposed for electrical vehicles. Based on 3-D finite element analysis, the influence of 10-, 11-, 13-, and 14-rotor-pole on the electromagnetic performance of DR-HEASFPM machine, including the magnetic field distribution, flux-linkage, back-EMF, flux regulation principles and capability, is comparatively investigated. The results show that the 6/10-, Ll-pole DR-HEASFPM machines exhibit higher PM flux-linkage and back-EMF. Moreover, the back-EMF of 6/11-pole machine is more sinusoidal and the flux-regulation capability is more excellent, which is suitable for wide speed-regulation application.

The industrial small-town development process in Shandong is influenced by the urban agglomeration strategy and the regional collaborative production, thereby resulting in a challenge of growth boundary planning. How to build a growth forecast decision support system to help small industrial towns maintain sustainable development with limited trial and error costs is an essential topic in the current research of small town-related fields. Empirical analysis reveals that the growth factors of small towns differ from the factors of cities due to the other-organization planning management system and self-organization construction activities that coexist in small towns. Besides, due to the size of small towns, the impact of policy changes in small towns is more significant than in cities. Furthermore, as part of the regional production chain, small industrial towns are most vulnerable to uncertain external disturbances. Therefore, it is necessary to formulate different development scenarios according to possible disturbances and output corresponding development forecasts. The research aims to build a decision-making support system for Shandong’s small-town planning based on an urban modeling approach using geographic information technology and scenario planning. Considering the mutually driving effects of the objective environment and subjective policies of Shandong’s industrial towns, as well as the corresponding dynamic mechanisms and comparing the theoretical basis and limitations of the different modeling approaches, this essay constructs a model system based on a mathematical model and a system dynamics model. It is also an interactive model accompanied by applicable rules and factors so that initial information and relevant development goals can be inputted into the model system to simulate the influence of different policies and identify the small industrial town growth scenarios.

Clarifying the differences of K-12 digital learning status can not only help us get a comprehensive understanding of digital learning for students in different types of schools, but also discover the problems in a timely manner and provide reference for educational decision makers. In this research, the differences of K-12 digital learning situation were explored from five dimensions, including digital learning environment (DLE), perception towards digital learning (PTDL), digital learning behavior (DLB), rich media integration (RMI) and computer- supported collaborative learning (CSCL). A total of 95,261 students from more than 1,000 schools participated in the research. One-way ANOVA analysis results indicate that there were no significant differences in DLE. There were significant differences in PTDL, DLB, RMI and CSCL among urban schools, township schools and rural schools. Based on the results of the study, some suggestions were presented such as construction of the smart learning environment, development of the media-rich resources and enhancement of the collaborative learning competency, which leads to the synergy promotion of digital learning level of students in different types of schools.

In traditional rural areas in China featuring both agriculture and aquiculture, shellfish waste (SW) was widely used, which created the typical rural cultural landscape (RCL). Nevertheless RCL is increasingly homogenized and traditional building techniques are inefficiently transformed; it has become a bottleneck in the reuse of SW whether the following problems can be solved, namely SW in large quantities but at low prices, secondary pollution, and the contradiction between high investments and low yields. In terms of generation background, material performance, and building process, an analysis was conducted on the generation mechanism of RCL with SW. Then the typical construction of traditional RCL was dissected and a new landscape structure was designed to coordinate appropriate technology and landscape features, which can be used to avoid the damage to coastal RCL caused by new structures of brick-concrete in “demolition and reconstruction” through “structural addition.” Finally, through the design research and based on reconstructing the overall ecological space of agricultural heritage. SW is used as material resources in the system engineering of building sustainable landscape systems in rural areas featuring both agriculture and aquiculture, forming the promotion mechanism of “mariculture zone-factories-sites.”

Axial field switched-flux permanent magnet (PM) (AFSFPM) machine is a stator-PM axial-flux machine, which exhibits many merits including simple and robust structure, short axial length, and high power/torque density. In this paper, a kind of direct torque control (DTC) method with flux-weakening strategy implementation, for the AFSFPM machine, is investigated. According to the stage control schemes, a given method with self-adaption for the flux-linkage, by remaining direct-axis is zero, is achieved in constant toque region. A flux-weakening control strategy is implemented in constant power region. On the basis of the DTC method, the performance of the drive system in the entire operating region is investigated. The results indicate that the proposed control strategy reduces the direct-axis component of armature current while increases the efficiency. Moreover, the constant power operating range is broaden. The effectiveness of the proposed method and the characteristics of the AFSFPM machine are verified. Therefore, the machine is very interesting in electrical vehicles (EV) or hybrid EVs (HEVs) application.

The process of compact development of rural settlements in the North China Plain is influenced by centralised control of planning spaces and a deficiency of self-built spaces, thereby resulting in a crisis of spatial characteristics. This essay considers the mutually driving effects of top-down planning spaces and bottom-up self-built spaces as well as the corresponding dynamic mechanisms of unified construction and self-help construction formed in spatial system evolution. The goal is to explore a method applicable for the organisation, evolution and generation of compact rural settlements. Furthermore, the essay defines generative rules governing planning and self-built spaces in spatio-temporal evolution for a model applicable to rural settlements. It is a co-evolution model accompanied by suitable algorithms and codes so that initial information and relevant rules can be inputted in Python. Automatically generated spatial data are outputted to visual software for generative design.

Hybrid excited axial field flux-switching permanent magnet (AFFSPM) (HEAFFSPM) machine is a novel stator-exciting hybrid excitation machine, which combines the advantages AFFSPM machine and wound-field excited machine. In this paper, an improved model predictive torque control (MPTC) method with duty cycle control by optimizing the active voltage vector duration is proposed for the HEAFFSPM machine drive system to reduce torque and flux ripples. On the basis of the theoretical analysis, a discrete-time model of the machine is established. Considering the flux-enhancing and flux-weakening algorithms, the different multiobjective cost functions are designed, and the multiple right weight coefficients are analyzed and chosen to optimize the system performance. The results indicate that the proposed control methods reduce the torque and flux ripples significantly compared with traditional MPTC, and the control system has better steady performance. Meanwhile, the load capacity is increased and the range of speed regulation is broadened.

Previously, we found that Celastrus orbiculatus Thunb. (COT) decreases athero-susceptibility in lipoproteins and the aorta of guinea pigs fed a high-fat diet, and increases high-density lipoprotein (HDL). In the present study, we investigated the effect of COT in reducing lipid accumulation and promoting reverse cholesterol transport (RCT) in vivo and vitro. Healthy male mice were treated with high-fat diet alone, high-fat diet with COT (10.0 g/kg/d), or general fodder for 6 weeks. Serum levels of total cholesterol (TC), triglyceride (TG), HDL-C, non-HDL-C, and (3)H-cholesterol in plasma, liver, bile, and feces were determined. Pathological changes and the levels of TC and TG in liver were examined. The expression of hepatic genes and protein associated with RCT were analyzed. COT administration reduced lipid accumulation in the liver, ameliorated the pathological changes, and lessened liver injury, the levels of TG, TC, and non-HDL-C in plasma were decreased significantly, and COT led to a significant increase in plasma HDL-C and apolipoprotein A (apoA1). (3)H-cholesterol in plasma, liver, bile, and feces was also significantly increased in COT-treated mice compared to controls. Both mRNA and protein expression of SRB1, CYP7A1, LDLR, ATP-binding cassette transporters ABCA1, ABCG5, and LXRα were improved in COT-treated mice. An in vitro isotope tracing experiment showed that COT and its bioactive ingredients, such as celastrol, ursolic acid, oleanolic acid, and quercetin, significantly increased the efflux of (3)H-cholesterol. They also increased the expression of SRB1, ABCA1, and ABCG1 significantly in macrophages. Our findings provided a positive role of COT in reducing lipid accumulation by promoting RCT. These effects may be achieved by activating the SRB1 and ABC transporter pathway and promoting cholesterol metabolism via the CYP7A1 pathway in vivo. The effective ingredients in vitro are celastrol, ursolic acid, oleanolic acid, and quercetin.

A hybrid axial-field flux-switching permanent magnet machine (HAFFSPMM) is a novel hybrid excited flux-switching permanent magnet motor, which combines the advantages of the axial-field flux-switching permanent magnet machine and hybrid excited synchronous machine. In this paper, based on the vector control method, the mathematical model of the HAFFSPMM is deduced and the operating performance of the HAFFSPMM in the entire operating region is investigated. A novel control scheme for the HAFFSPMM drive system, including the $i_{d }=0$ and flux-weakening strategy, is proposed. To improve the robustness of the control system, the parameters of the proportional-integral (PI) controller are optimized using the particle swarm optimization (PSO) algorithm. The experimental results demonstrate that the proposed control strategy can maximize the output torque and speed range of the drive system, and the PSO-PI controller can reduce the torque ripple and improve the stability of the control system. Moreover, the strong flux-weakening ability, large load capacity, high power, and torque density of the HAFFSPMM are validated.

Hybrid excited axial field flux-switching permanent magnet (AFFSPM) (HEAFFSPM) machine is a novel stator-excitation hybrid excited synchronous machine, which combines the advantages of AFFSPM machine and wound-field excitation machine. In this paper, the structure feature of HEAFFSPM machine is analyzed, and the mathematical model is established. In order to improve the power factor of drive system for the HEAFFSPM machine and make full use of the inverter capability, a kind of unity power factor (UPF) control method is proposed, and the operating performance of HEAFFSPM machine is investigated. The validity of the proposed control method is verified by the simulation and experimental research. The results indicate the UPF can be achieved at different speed and load while the constant torque region is extended by using the UPF control method compared with the zero d-axis current control.

Hybrid excited axial field flux-switching machine (HEAFFSM) is a novel hybrid excited flux-switching permanent magnet machine, which combines the advantages of the hybrid excited synchronous machine and axial field flux-switching permanent magnet machine. Based on the vector control method, a novel control strategy of stator-flux orientation for the HEAFFSM, which can operate in both flux-enhancing and flux-weakening modes, is proposed. The operating performance of the HEAFFSM is investigated in the entire operation region according to the proposed strategy. The simulation and experimental results show that the proposed method is simple and convenient to control, and extends the constant power operating range. Moreover, the characteristics of the HEAFFSM, including the load capability and flux-regulation capability, are validated.

Axial field flux-switching permanent magnet (AFFSPM) machine is novel permanent magnet machine which combines the advantages of permanent magnet synchronous motor (PMSM) and flux-switching machine. In order to study the operating performance of AFFSPM machine in the whole speed range, the drive system of AFFSPM machine is investigated based on vector control. In this paper, the topology of AFFSPM machine is introduced and the mathematical model of AFFSPM machine is deduced. The id=0 control is employed in constant torque region and the flux-weakening control is adopted in constant power region. The simulation and experimental analysis are carried out by using matlab and dSPACE 1103 platform. The experimental results are consistent with simulation results and theoretical analysis. The results show that AFFSPM machine is relatively very suitable for in-wheel motor of Electric Vehicles (EVs).

E-core axial field flux-switching permanent magnet machine (AFFSPMM) is a novel topology. It can be applied in the field of electric and hybrid vehicles because of the short axial size, large torque density and fault tolerance. The filed windings can be wounded around the middle tooth of the E-core topology to carry out the hybrid excitation. In the paper, the E-core topologies with and without field windings are investigated by 3D finite element analysis (FEA). The characteristics of the two topologies are compared, including back-EMF, inductance and torque etc. The FE-predicted results show the torque and fault tolerance in the E-core AFFSPMM without field windings is higher than those in the machine with field windings, while the operation range can be extended in the E-core AFFSPMM with field windings since the field current in the field windings can regulate the flux linkage in each phase windings. Meanwhile, the open-circuit and short-circuit fault is investigated and analyzed by transient analysis. It is also validated that the AFFSPMM without field windings has better fault tolerance.

The study aimed to investigate the effect of niacin on vascular inflammatory lesionsin vivoandin vitroas well as its lipid-regulating mechanism.In vivostudy revealed that niacin downregulated the levels of inflammatory factors (IL-6 and TNF-α) in plasma, suppressed protein expression of CD68 and NF-κB p65 in arterial wall, and attenuated oxidative stress in guinea pigs that have been fed high fat diet.In vitrostudy further confirmed that niacin decreased the secretion of IL-6 and TNF-αand inhibited NF-κB p65 and notch1 protein expression in oxLDL-stimulated HUVECs and THP-1 macrophages. Moreover, niacin attenuated oxLDL-induced apoptosis of HUVECs as well. In addition, niacin significantly lessened lipid deposition in arterial wall, increased HDL-C and apoA levels and decreased TG and non-HDL-C levels in plasma, and upregulated the mRNA amount of cholesterol 7α-hydroxylase A1 in liver of guinea pigs. These data suggest for the first time that niacin inhibits vascular inflammationin vivoandin vitrovia downregulating NF-κB signaling pathway. Furthermore, niacin also modulates plasma lipid by upregulating the expression of factors involved in the process of reverse cholesterol transport.

In this paper, the influence of the design parameters of a axial field flux-switching permanent magnet (AFFSPM) machine on the maximum output torque is investigated by 3D finite element method (FEM) and validated by measurements made on a prototype AFFSPM machine. These parameters include the stator tooth width, the stator magnet thickness, the stator yoke thickness, the stator tooth shape, the rotor pole width, and the rotor pole shape, etc. The results show that the AFFSPM machine having equal stator tooth width, stator magnet thickness and slot opening produces the maximum output torque. The torque can be increased by 10% if the stator yoke thickness is reduced to 3mm. The output torque can be increased further by optimizing the rotor pole width and shape. The output torque can be increased by 40% if the rotor pole width is optimized to 13.5° and the fan-shaped rotor pole can further increase the output torque.

To build up a new contour and functional reconstruction technique of mandibular defects with rapid prototyping and reverse engineering technique.From April 2002 to August 2004, 4 cases of mandibular defects due to resection of large mandible lesion were treated. Of 4 patients, there were 3 females and 1 male, with an age range of 21-42 years, which underwent secondary operation and presented a deviation as mandibular movement. The opening-mouth extent was 1.8-2.5 cm (2.2 cm on average). The data of defects area were renewed with Mimics and Geomagic Studio software; and the titanium reconstructive frame was designed and manufactured with rapid prototyping technique. Defect were reconstructed by using CT digital data of patients.The CT data could be used by image software directly. The implant design could be completed by computer-aimed design (CAD) / computer-aided manufacture (CAM). The resin model and titanium frame were manufactured accurately by RP technique. Four patients achieved one stage healing. After a follow-up of 3 months to 2 years, large mandibular defect was reconstructed satisfactorily and the opening-mouth extent was 3.0-3.4 cm (3.2 cm on average). The occluding relation was normal. The implant denture was put on and the mastication function was good in 1 case.Individual design and repair of large mandibular defect with CAD/CAM techniques is worth extending application clinically. It is a simple and accurate method.

We describe a new osteotomy for transport of a disc of alveolar bone, which can simultaneously close an oronasal fistula with two layers of mucoperiosteum during distraction osteogenesis for reconstruction of a maxillary defect.