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Metadiscourse is an important dialogue technique used in productive knowledge building to help a group evaluate and advance their knowledge progress. Previous studies have identified and defined various types of metadiscourse. However, there is scant knowledge about how different metadiscourse types emerge among different groups or what implicit correlations lie between progressive discourse and metadiscourse. Moreover, research on how different types of metadiscourse influence groups' knowledge advancement and artifacts is still inadequate. Therefore, this study aims to further examine the roles that different types of metadiscourse play in the collaborative knowledge building community on both a fine-grained (i.e. progressive discourse) and coarse-grained (i.e. group knowledge advancement and group artifacts) level.

Data for this study are drawn from the behaviour of undergraduate students participating in a 12-week course at a key university in China. On the fine-grained level, epistemic network analysis (ENA) is applied to illustrate how metadiscourse promotes the development of progressive discourse. On the coarse-grained level, two different chi-square tests are conducted to examine the roles of different types of metadiscourse in groups' knowledge advancement and artifacts.

The analysis allowed several conclusions to be drawn. First, the types of metadiscourse that students most often adopted were reflecting on ideas development (RD) and commenting on ideas (CI); they less frequently adopted setting group goals (SG) and making group plans (MP). Second, most types of metadiscourse correlated with developments in progressive discourse, particularly RD and CI. Third, the metadiscourse types RD, CI and coordinating group efforts (CE) played essential roles in knowledge advancement. Fourth, higher-quality artifacts could be created by using the metadiscourse type reviewing the state of knowledge building progress (RP).

A more profound comprehension of the role that metadiscourse plays in the collaborative knowledge building community not only contributes to the literature in the knowledge building field but also carries a significant meaning in regulating community, promoting learner agency and sustained knowledge, and consequently improving collaborative learning performance.

This paper aims to study a new halogen-free fame-retardant curing agent 1-aminoethylidenediphosphonate (AAEDP).

The AAEDP was synthesized by phosphoric acid, acetonitrile and ammonia. The chemical structures of AAEDP were characterized by proton nuclear magnetic resonance, mass spectrometry and Fourier transform infrared spectrometer. Thermal gravimetric analysis (TGA) and scanning electron microscope (SEM) would study the thermal properties and the char residues of AAEDP/EP. The thermal stability, mechanical and flame properties and morphology for the char layer of composite materials were separately investigated using TGA, tensile and charpy impact tests, limiting oxygen index (LOI), UL-94 HB flammability standard (UL-94) and SEM.

The results showed that the AAEDP had been prepared successfully. When the intumescent flame retardant was added into the EP, the LOI of composite material was improved.

The AAEDP can be prepared successfully and can improve the flame resistance of composite material.

The AAEDP has excellent flame-retardant properties and produce no toxic fumes when burnt in case of fire.

The results showed that the phosphorus content of AAEDP was 2.958 Wt.%; the impact and tensile strength of the composite material were 6.417 kJ m⁻² and 38.0 MPa, respectively; and the LOI and UL-94 were 29.7% and V-0 ranking, respectively. The TGA results indicated that the carbon residue ratio can be increased by 1000°C in air. The denser and more uniform structure of residual carbon prevents heat transfer and diffusion, restricts the production of combustible gas and reduces the rate of heat release.

The purpose of this paper is to examine how developing country brand name and brand origin affect the customer’s evaluation of the brand in radically new high-tech products. Using processing fluency as a theoretical underpinning, this study can answer the following questions: first, does foreign brand name (developed vs developing Asian brand name) affect the customer’s attitude toward the brand? Second, does the brand origin (developed vs developing country) moderate the effect of foreign brand name on attitude toward the brand? Third, does the individual difference (knowledge and technological sophistication) matter in determining the brand origin and fit effect on willingness to buy?

A 2×2 between subject experiment was conducted in which two factors were manipulated: foreign brand name (developed: Japan vs developing: China) and brand origin (developed: Japan vs developing: China).

The fit between brand origin and brand name leads to better evaluation of the brand than no fit. On the other hand, for developing country brand origin (e.g. China), the brand naming effect is mitigated by enhanced processing fluency caused by fit, which leads to better evaluation of developing country brand. Fit effect is more pronounced for more knowledgeable consumers. Technologically more sophisticated consumers are more willing to buy the developing country brand origin than technologically less sophisticated consumers due to the processing fluency effect.

This paper introduces the two dimensions of foreign brand name (developed vs developing) and examines the interaction with the brand origin. This research fills the gap of under-researched area in brand naming literature, which is the effect of developing country brand naming on attitude toward the brand of radically new high-tech products. This research extends the previous literature by applying linguistic mechanism, processing fluency to examine the Asian brand naming including emerging market. This research makes an important theoretical contribution by identifying an underlying individual-level construct, “knowledge” and “technological sophistication,” which explains and influences the effects of brand name and brand origin on willingness to buy the brand.

Since carbon nanotubes (CNTs) were discovered by Iijima in 1991, they have gained more and more attention by people because of their unique physical and chemical properties. The CNTs have one-dimensional nanostructure, high surface adsorption capacity, good conductivity and electronic ballistic transmission characteristics and therefore have excellent mechanical, electrical, physical and chemical properties. CNTs are ideal basic materials to make nanometer gas sensors. Nanometallic materials function as to enhance electrode activity and promote the electron transfer, so if composite nanometallic materials M (such as Au, Pt, Cu and Pd) and CNTs are used, all kinds of their characters of components would have coeffect. Electrochemical sensors by use of such composite as electrode would have a higher detection sensitivity.

CNTs were synthesized via chemical vapor deposition technique and were purified afterward. CNTs-M(Pt,Au) suspension was prepared by chemical deposition using spinning disc processor (SDP) and was coated on gold electrode. The modified electrodes were constructed, based on immobilization of glucose oxidase on an Au electrode by electrostatic effect. CNTs-Pt/ glassy carbon electrodes (GCE) electrodes were made by electrochemically deposition of platinum particles on GCE modified by CNTs. The microstructures of the harvested CNTs, CNTs-M (M = Au, Pt) were analyzed under scanning electron microscopy and transmission electron microscopy. The application of the sensor in medical detection has been evaluated.

The results shown that CNTs-Au biosensors exhibit good reproducibility, stability and fast response to glucose detection, it can be used in the clinic detection of glucose concentration in human serum. Using CNTs-Pt/GCE for formaldehyde detection exhibited high sensitivity and good reproducibility.

This study modified CNTs by using self-assembled techniques through SDP with nano Pt and Au by electrodeposition for the first time. CNTs-Pt/GCE electrode was prepared by depositing platinum particles electrochemically on GCE modified by CNTs. CNTs-Au-modified electrode was prepared by immobilization of glucose oxidase on an Au electrode first by electrostatic effect. Electrochemical behaviors of glucose at CNTs-Au and formaldehyde at CNTs-Pt/GCE were investigated by cyclic voltammetry.

This study aims to examine the relationship between green technology implementation (GTI), knowledge management (KM) process and knowledge workers' operational performance (KWOP). The research postulates that a specific combination of GTI and KM processes can lead to improving KWOP.

The sample data (304) were taken from those manufacturing firms that are utilizing green technology. The examination was conducted by Smart PLS-SEM and fuzzy set qualitative comparative analysis (fsQCA). The Smart PLS 3.29 is used to verify certain variable relationships. Moreover, fsQCA is used to investigate multiple configuration paths to enhance KWOP.

The study's outcome indicated that GTI positively influences the KM process in manufacturing firms, and the KM process enormously improves KWOP. The fsQCA analysis result explores various integrations (communication, collaboration, supporting role and improved performance) with the KM (acquisition, sharing and utilization) process identified to enhance the performance of KWOP. The current study supports two merging methods to deepen understanding of employee operational performance.

The study methodologically contributes by integrating direct and configuration approaches to develop firms' operational performance. This study contributes to bridging research gaps in the prior literature and advances insight into the association between GTI, KM process and KWOP.

This paper aims to provide a detailed review of weak interaction biosensors and several common biosensor methods for magnifying signals, as well as judiciously guide readers through selecting an appropriate detecting system and signal amplification method according to their research and application purpose.

This paper classifies the weak interactions between biomolecules, summarizes the common signal amplification methods used in biosensor design and compares the performance of different kinds of biosensors. It highlights a potential electrochemical signal amplification method: the G protein signaling cascade amplification system.

Developed biosensors which, based on various principles, have their own strengths and weaknesses have met the basic detection requirements for weak interaction between biomolecules: the selectivity, sensitivity and detection limit of biosensors have been consistently improving with the use of new signal amplification methods. However, most of the weak interaction biosensors stop at the research stage; there are only a minority realization of final commercial application.

This paper evaluates the status of research and application of weak interaction biosensors systematically. The G protein signaling cascade amplification system proposal offers a new avenue for the research and development of electrochemical biosensors.

Fuel cells technologies are the most promising green energy technologies for diverse applications. One of the fastest growing areas is the portable electronic applications where the power range is the order of 1–100 W. For most of the portable electronic devices, rechargeable battery is the major energy source. Due to limitations like limited capacity, requirement of external power for recharge have led many researchers to look for alternative power sources to power portable electronic devices. The high energy density of fuel cells makes them very attractive alternative to batteries for portable power applications. There are a variety of fuel cell technologies being considered to replace batteries in portable electronic equipment. Direct Liquid Fuel Cells (DLFCs) have attracted much attention due to their potential applications as a power source for portable electronic devices. The advantages of DLFCs over hydrogen fed PEM fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. Unlike batteries, fuel cells need not be recharged, merely refueled. This paper provides an overview on challenges of DLFCs (Direct Liquid Fuel Cells), like fuel crossover, cost, durability, water management, weight and size along with approaches being investigated to solve these challenges. Portable Fuel Cell Commercialization Targets for future and producers of portable fuel cells across the globe are also discussed in this paper.

Discusses the pattern of the regional distribution in the Chinese economy of Direct foreign investment (DFI) in the context of the open‐door policy and the regional difference in investment environments. Presents a regression analysis on the effects of DFI on the economic growth in the eastern and western regions, using pooled time‐series and cross‐section data for 16 provinces over a seven‐year period (1986‐92). Discusses other important factors influencing regional economic development including rural industry development, differential growth of fixed capital investment and exports, and domestic capital flow from the western region to the eastern region. A case study of the effect of DFI on the intra‐provincial economic inequality in Guangdong Province is presented and some conclusions and policy implications are drawn.

This paper aims to investigate the influence of different post-annealing cooling conditions, i.e. furnace cooling (heat treatment (HT) 1 – slow cooling) and air cooling (HT 2 – fast cooling), on the microstructure and mechanical properties of selective laser melting (SLM) built austenitic 316L stainless steel (SS).

Three sets of 316L SS samples were fabricated using a machine standard scanning strategy. Each set consists of three tensile samples and a cubic sample for microstructural investigations. Two sets were subsequently subjected to annealing HT with different cooling conditions, i.e. HT 1 and HT 2, whereas one set was used in the as-built (AB) condition. The standard metallographic techniques of X-ray diffraction, scanning electron microscopy and electron back-scattered diffraction were used to investigate the microstructural variations induced by different cooling conditions. The resultant changes in mechanical properties were also investigated.

The phase change of SLM fabricated 316L was observed to be independent of the investigated cooling conditions and all samples consist of austenite phase only. Both HT 1 and HT 2 lead to dissolved characteristic melt pools of SLM. Noticeable increase in grain size of HT 1 and HT 2 samples was also observed. Compared with AB samples, the grain size of HT 1 and HT 2 was increased by 12.5% and 50%, respectively. A decreased hardness and strength, along with an increased ductility was also observed for HT 2 samples compared with HT 1 and AB samples.

From previous studies, it has been noticed that most investigations on HT of SLM fabricated 316L were mainly focused on the HT temperature or holding time. However, the post-HT cooling rate is also an equally important factor in deciding the microstructure and mechanical properties of heat-treated components. Therefore, this paper investigates the influence of different post-annealing cooling conditions on microstructure and mechanical properties of SLM fabricated 316L components. This study provides a foundation for considering the post-HT cooling rate as an influential parameter that controls the properties of heat-treated SLM components.

Simultaneous localization and map building (SLAM), as a state estimation problem, is a prerequisite for solving the problem of autonomous vehicle motion in unknown environments. Existing algorithms are based on laser or visual odometry; however, the lidar sensing range is small, the amount of data features is small, the camera is vulnerable to external conditions and the localization and map building cannot be performed stably and accurately using a single sensor. This paper aims to propose a laser three dimensions tightly coupled map building method that incorporates visual information, and uses laser point cloud information and image information to complement each other to improve the overall performance of the algorithm.

The visual feature points are first matched at the front end of the method, and the mismatched point pairs are removed using the bidirectional random sample consensus (RANSAC) algorithm. The laser point cloud is then used to obtain its depth information, while the two types of feature points are fed into the pose estimation module for a tightly coupled local bundle adjustment solution using a heuristic simulated annealing algorithm. Finally, the visual bag-of-words model is fused in the laser point cloud information to establish a threshold to construct a loopback framework to further reduce the cumulative drift error of the system over time.

Experiments on publicly available data sets show that the proposed method in this paper can match its real trajectory well. For various scenes, the map can be constructed by using the complementary laser and vision sensors, with high accuracy and robustness. At the same time, the method is verified in a real environment using an autonomous walking acquisition platform, and the system loaded with the method can run well for a long time and take into account the environmental adaptability of multiple scenes.

A multi-sensor data tight coupling method is proposed to fuse laser and vision information for optimal solution of the positional attitude. A bidirectional RANSAC algorithm is used for the removal of visual mismatched point pairs. Further, oriented fast and rotated brief feature points are used to build a bag-of-words model and construct a real-time loopback framework to reduce error accumulation. According to the experimental validation results, the accuracy and robustness of the single-sensor SLAM algorithm can be improved.