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Past studies have provided important insights into the relationship between science education and information and communication technologies (ICTs). However, few studies have sought to promote learning by integrating science education with indigenous culture via ICTs. Indigenous culture is a treasure of human civilization, but there is a crisis of rapid disappearance. Integrating indigenous culture into students' science education may help them understand the scientific implications of their culture, and preserve and participate in their cultural activities. This study explores the relationships between science education and indigenous culture through the use of ICTs in the context of Taiwan's Rukai tribe. A research process was proposed with three steps: planning, execution, and evaluation. There were 15 indigenous pre-service teachers from six tribes participating in the study. The results show that ICTs help them understand the scientific principles of their own culture, and develop practical materials and lesson plans that can be used for future teaching. It also makes them aware of the meaning and importance of their own culture.

Hand, foot, and mouth disease (HFMD) is an epidemic infectious disease in China. Its incidence is affected by a variety of natural environmental and socioeconomic factors, and its transmission has strong seasonal and spatial heterogeneity. To quantify the spatial relationship between the incidence of HFMD (I-HFMD) and eight potential risk factors (temperature, humidity, precipitation, wind speed, air pressure, altitude, child population density, and per capita GDP) on the Chinese mainland, we established a geographically weighted regression (GWR) model to analyze their impacts in different seasons and provinces. The GWR model successfully describes the spatial changes of the influence of potential risks, and shows greatly improved estimation performance compared with the ordinary linear regression (OLR) method. Our findings help to understand the seasonally and spatially relevant effects of natural environmental and socioeconomic factors on the I-HFMD, and can provide information to be used to develop effective prevention strategies against HFMD at different locations and in different seasons.

For sparse code multiple access (SCMA) with traditional codebooks, the initial information of message passing algorithm (MPA) receiver is easily susceptible to noise and multipath fading, and the convergence reliability of the first detected user in each decision process is unsatisfactory. Driven by these problems, an optimized codebook design for SCMA is presented in this paper. In the proposed SCMA codebook design, we first use turbo trellis coded modulation technology to design a basic complex multi-dimension constellation, which can increase the minimum Euclidean distance. Then, phase rotation and coordinate interleaving are added on the constellation to increase diversity and coordinate product distance between any constellation points. Based on these, we propose a novel criterion to select the most appropriate permutation set, which can capture as large as the sum of distance between dimensions of interfering codewords multiplexed on each resource node and maximize the diversity over the set of the sums of distance between dimensions of interfering codewords multiplexed on all resource nodes. Benefiting from the proposed codebook design, the quality of initial information of MPA receiver on each resource node and the convergence reliability of the first detected user in each decision process will be improved. Simulation results show that the bit error rate performance of SCMA with the proposed codebooks outperforms SCMA with traditional codebooks, low-density signature, and orthogonal frequency division multiple access under the same load.

Aiming at the characteristics of closed fixtures such as large size, heavy weight and difficulty in high-altitude operation, this study proposed a design method to improve the clamping apparatus for replacement of insulator strings in the ultra-high-voltage (UHV) transmission line. After modelling through the finite element method, the mechanical properties of the clamping apparatus are analysed to determine the structure with the fixtures of carbon fibre composites. The proposed clamping apparatus will have the characteristics as high strength, high modulus and low weight, so that if applied in the UHV transmission line, the working efficiency will be improved and the labour intensity will be reduced.

The relation between the microstructure and mechanical properties of the Fe–Nb dissimilar joint were investigated using nanoindentation. The weld metal consists mainly of Fe2Nb, α-Fe + Fe2Nb, Nb (s,s) and Fe7Nb6 phases. Radial cracks initiate from the corners of the impressions on the Fe2Nb phase (~20.5 GPa) when subjected to a peak load of 300 mN, whereas the fine lamellar structures (α-Fe + Fe2Nb) with an average hardness of 6.5 GPa are free from cracks. The calculated fracture toughness of the Fe2Nb intermetallics is 1.41 ± 0.53 MPam1/2. A simplified scenario of weld formation together with the thermal cycle is proposed to elaborate the way local phase determined the mechanical properties.

Objective To study the effect of tetrandrine (TET) on oral squamous cell carcinoma cell line Tca8113 and its influence against the expression of β-catenin.Methods CCK-8 method was used to detect the effect of TET on Tca8113 by different dose and time. Western blot assay was used to detect the expression of β-catenin after treatment by TET meanwhile the distribution of the β-catenin treated by TET was detected by the immunofluorescence method.Results With the increasing dose of TET, the inhibition rate against Tca8113 was raising (P < 0.05). The half maximal inhibitory concentration (IC50) value of TET against Tca8113 was 64 μmol/L. With this concentration, the inhibition rate against Tca8113 exhibited a time-dependent manner. The results of western blot revealed that the expression of β-catenin was significantly inhibited after treatment by TET (P < 0.05). The results of immunofluorescence method showed that the β-catenin protein mainly located at nucleus in Tca8113, while after treatment by TET, the β-catenin protein mainly located at cellular membrane and cytoplasm in a diffused distribution manner.Conclusion Our data suggest that TET can inhibit the cell growth of oral squamous cell carcinoma, and influence the cellular distribution of β-catenin protein in tumor cells.

Colloidal quantum dots (CQDs) are attractive materials for solar cells due to their low cost, ease of fabrication and spectral tunability. Progress in CQD photovoltaic technology over the past decade has resulted in power conversion efficiencies approaching 10%. In this review, we give an overview of this progress, and discuss limiting mechanisms and paths for future improvement in CQD solar cell technology.We briefly summarize nanoparticle synthesis and film processing methods and evaluate the optoelectronic properties of CQD films, including the crucial role that surface ligands play in materials performance. We give an overview of device architecture engineering in CQD solar cells. The compromise between carrier extraction and photon absorption in CQD photovoltaics is analyzed along with different strategies for overcoming this trade-off. We then focus on recent advances in absorption enhancement through innovative device design and the use of nanophotonics. Several light-trapping schemes, which have resulted in large increases in cell photocurrent, are described in detail. In particular, integrating plasmonic elements into CQD devices has emerged as a promising approach to enhance photon absorption through both near-field coupling and far-field scattering effects. We also discuss strategies for overcoming the single junction efficiency limits in CQD solar cells, including tandem architectures, multiple exciton generation and hybrid materials schemes. Finally, we offer a perspective on future directions for the field and the most promising paths for achieving higher device efficiencies.

For the conveyor belt, variable material flow influences the energy efficiency of the speed control technology significantly. The fluctuation of material flow on the conveyor belt will lead to the detrimental vibrations on both the belt and the conveyor while the conveyor works at certain speeds. In order to improve the model inaccuracy caused by the uniform bulk material flow assumption in the current conveyor belt model, the paper establishes a high-precision dynamic model that can consider speed control of a conveyor belt under non-uniform bulk material transportation. In this dynamic model, a non-uniform bulk material distribution model is firstly proposed based on laser scanning technology. Then, a high-precision longitudinal dynamic model is proposed to investigate the dynamic behavior of a belt conveyor. Considering the micro-units of actual load on a conveyor belt, it can well describe the transient state of the conveyor belt. These models can be used to determine the optimal speed for safety and energy conservation in operation. Experimental results are used to validate the proposed dynamic model for analyzing belt mechanical behavior under non-uniform bulk material distribution on the belt. The results show that the proposed models can be used for optimizing the operating procedures of belt conveyor systems.

The buzz phenomenon of a typical supersonic inlet is analyzed on the basis of numerical simulations and duct acoustic theory. Considering that the choked inlet could be treated as a duct with one end closed, a one-dimensional (1D) mathematical model based on the duct acoustic theory is proposed to describe the periodic pressure oscillation of the little buzz and the big buzz. The results of the acoustic model agree well with that of the numerical simulations and the experimental data. It could verify that the dominated oscillation patterns of the little buzz and the big buzz are closely related to the first and second resonant mode of the standing wave, respectively. The discrepancies between the numerical simulation and the ideal acoustic model might be attributed to the viscous damping in the fluid oscillation system. In order to explore the damping, a small perturbation jet is introduced to trigger the resonance of the buzz system and the nonlinear amplification effect of resonance might be helpful to estimate the damping. Through the comparison between the linear acoustic model and the nonlinear simulation, the calculated pressure oscillation damping of the little buzz and the big buzz are 0.33 and 0.16, which could be regarded as an estimation of real damping.

Metamodels have become increasingly popular in the field of energy sources because of their significant advantages in reducing the computational cost of time-consuming tasks. Lacking the prior knowledge of actual physical systems, it may be difficult to find an appropriate metamodel in advance for a new task. A favorite way of overcoming this difficulty is to construct an ensemble metamodel by assembling two or more individual metamodels. Motivated by the existing works, a novel metamodeling approach for building the ensemble metamodels is proposed in this paper. By thoroughly exploring the characteristics of regression-type and interpolation-type metamodels, some useful information is extracted from the feedback of the regression-type metamodels to further improve the functional fitting capability of the ensemble metamodels. Four types of ensemble metamodels were constructed by choosing four individual metamodels. Common benchmark problems are chosen to compare the performance of the individual and ensemble metamodels. The results show that the proposed metamodeling approach reduces the risk of selecting the worst individual metamodel and improves the accuracy of the used individual metamodels.

This research deals with a multi-floor bus station, which provides services for a large number of passengers. The bus station has a limited platform capacity and there is no temporary parking lot for buses. When a large number of buses move into one floor of the station, buses cannot move smoothly and may not even be able to move at all. When a floor is full, buses waiting outside cannot enter, and buses inside cannot move out. It is fortunate that the station is designed as a multi-floor structure. When a bus is scheduled to move onto a floor, which has no more space for parking, it can move to another floor temporarily to wait. This research proposes the use of integer-programming to optimize the assignment of temporary waiting floor for all incoming buses in order to minimize the maximum delay. A Variance Neighbourhood Search (VNS) is proposed to solve the problem. The results show that when temporary waiting on another floor is permitted, the total time delay can be reduced by up to 47.41%.

As a classical herb pair in clinics of traditional Chinese medicine, Curcumae Rhizoma–Sparganii Rhizoma (HP CR–SR) is used for activating blood circulation to remove blood stasis. The essential components in HP CR–SR and its single herbs were comparatively analyzed using gas chromatography-mass spectrometry data. 66, 22, and 54 components in volatile oils of Curcumae Rhizoma, Sparganii Rhizoma, and HP CR–SR were identified, and total contents accounted for 75.416%, 91.857%, and 79.553% respectively. The thirty-eight components were found in HP CR–SR, and not detected in single herbs Curcumae Rhizoma and Sparganii Rhizoma. The highest radical trapping action was seen by an essential oil of HP CR–SR (IC50 = 0.59 ± 0.04 mg/mL). Furthermore, the HP CR–SR essential oil showed more remarkable cytotoxicity on tumor cell lines than that of the single herbs Curcumae Rhizoma and Sparganii Rhizoma in a dose-dependent manner: IC50 values showing 32.32 ± 5.31 μg/mL (HeLa), 34.76 ± 1.82 μg/mL (BGC823), 74.84 ± 1.66 μg/mL (MCF-7), 66.12 ± 11.23 μg/mL (SKOV3), and 708.24 ± 943.91 μg/mL (A549), respectively. In summary, the essential oil of HP CR–SR is different from any one of Curcumae Rhizoma and Sparganii Rhizoma, nor simply their superposition, and HP CR–SR oil presented more remarkable anticancer and antioxidant activities compared with Curcumae Rhizoma and Sparganii Rhizoma oils.

Component fingerprints are a recognized method used worldwide to evaluate the quality of traditional Chinese medicines (TCMs). To foster the strengths and circumvent the weaknesses of the fingerprint technique in TCM, spectrum-effect relationships would complementarily clarify the nature of pharmacodynamic effects in the practice of TCM. The application of the spectrum-effect relationship method is crucial for understanding and interpreting TCM development, especially in the view of the trends towards TCM modernization and standardization. The basic requirement for using this method is in-depth knowledge of the active material basis and mechanisms of action. It is a novel and effective approach to study TCMs and great progress has been made, but to make it more accurate for TCM research purposes, more efforts are needed. In this review, the authors summarize the current knowledge about the spectrum-effect relationship method, including the fingerprint methods, pharmacodynamics studies and the methods of establishing relationships between the fingerprints and pharmacodynamics. Some speculation regarding future perspectives for spectrum-effect relationship approaches in TCM modernization and standardization are also proposed.