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[Objective] Part of oil and gas pipelines in China, which have been in operation for a long time, are facing problems such as the lack of specific geographic information and deviation of the pipeline from the designed laying location. However, traditional pipeline localization methods possess limitations of significant cumulative errors and low accuracy. [Methods] To enhance the precision of oil and gas pipeline localization, a new method was proposed based on improved Unscented Kalman Filter(UKF) algorithm. The primary equipment,which is an inertial measurement unit consisting of a gyroscope and an accelerometer, supplemented by a wheel odometer and ground markers as auxiliary locator devices was utilized in this method. The attitude, velocity, and position errors of the pipeline detector were taken as state variables, and the speed of the wheel odometer and attitude information obtained from the solution of accelerometer data were taken as observables, to establish a nonlinear error propagation model of strap-down inertial navigation system. An improved UKF algorithm was employed to estimate the error transfer model for reducing the impact of noise on localization accuracy. The angular velocity and acceleration information were corrected by combining forward-backward smoothing filter method and straight and curved pipe identification method,to further reduce cumulative errors in the system solution process. [Results] Numerical simulations and physical experiments revealed that the proposed oil and gas pipeline localization system has significantly reduced cumulative errors in locating long-distance pipelines. The maximum error in determining the specific location of oil and gas pipelines was found to be 0.56%. The UKF algorithm, which was proposed in this paper, showed a locating accuracy level of approximately 34.2% higher compared to the traditional Kalman Filter(KF) algorithm and 30.2% higher compared to the UKF algorithm under constant testing conditions. [Conclusion] The proposed oil and gas pipeline locating method based on an improved UKF presents high practical value for long-distance pipeline localization as it has lower cumulative errors in the system solution process and higher accuracy in pipeline localization.

In order to explore the contextual factors that may influence Chinese early study abroad students' acculturation experiences in Canada, we conducted in-depth interviews with 20 Chinese early study abroad students and 6 Chinese parents. Using Oppedal and Toppelberg's acculturation development model as the analytical framework, we identify six microsystem factors (parents, host family, custodian, overseas-study service agent, friends, and church), two mesosystem factors (parents-custodian relationship and custodian-host family relationship), three exosystem factors (social services, public safety, and immigration policies), one majority culture macro factor (multiculturalism), and the time dimension are related to Chinese early study abroad students' acculturation experiences. In addition to these factors, locosystem factors such as geography, physical environment, and climate of the city in which they live are also important. Based on these findings, we advise all stakeholders to create a supportive and sustainable environment for Chinese early study abroad students to live in Canada.

With the growing trend of globalization, an increasing number of Chinese students choose to study overseas. While researchers have conducted many studies to explore factors motivating these students to undertake higher education overseas, few studies have investigated Chinese students' motivations to pursue secondary education abroad. To fill this research gap, we interviewed 20 Chinese secondary students and four Chinese parents to explore Chinese students' motivations to pursue secondary education abroad by taking Canada as a study destination example. By adopting the push-pull model as the theoretical framework, we identify two macro-level push factors and three micro-level push factors that propel Chinese secondary students to study outside China. It also reveals five pull factors at the macro-level and two pull factors at the micro-level that attract these students to select Canada as a study abroad destination. On the basis of identifying these push-pull factors, we further discuss the similarities and differences of Chinese students' motivations to pursue secondary education abroad and to undertake higher education overseas.

Accurately measuring the thickness of the oxide film that accumulates on nuclear fuel assemblies is critical for maintaining nuclear power plant safety. Oxide film thickness typically ranges from a few micrometers to several tens of micrometers, necessitating a high-precision measurement system. Eddy current testing (ECT) is commonly employed during poolside inspections due to its simplicity and ease of on-site implementation. The use of swept frequency technology can mitigate the impact of interference parameters and improve the measurement accuracy of ECT. However, as the nuclear assembly is placed in a pool for inspection, a cable several dozen meters in length is used to connect the ECT probe to the instrument. The measurement is affected by the transmission line and its effect is a function of the operating frequencies, resulting in errors for swept frequency measurements. This paper proposes a method for precisely measuring oxide film thickness based on the swept frequency technique and long transmission line impedance correction. The signals are calibrated based on a transmission line model of the cable, effectively eliminating the influence of the transmission cable. A swept frequency signal-processing algorithm is developed to separate the parameters and calculate oxide film thickness. To verify the feasibility of the method, measurements are conducted on fuel cladding samples with varying conductivities. It is found that the method can accurately assess oxide film thickness with varying conductivity. The maximum error is 3.42 μm, while the average error is 1.82 μm. The impedance correction reduces the error by 66%. The experimental results indicate that this method can eliminate the impact of long transmission cables, and the algorithm can mitigate the influence of material conductivity. This method can be utilized to measure oxide film thickness in nuclear power maintenance inspections following extensive testing and engineering optimization. [ABSTRACT FROM AUTHOR]

Reflective e‐paper displays show promising prospects with the increasing demand for energy‐efficient and sustainable technologies. However, the intrinsic incapability to display in dark environments hinders their broader application, and it is significantly important to enable reflective displays to achieve good display effects under various lighting conditions. Here, a flexible dual‐mode display device is proposed, which can demonstrate both reflective and emissive modes and achieve swift and straightforward mode switching by altering the driving waveforms. The single display layer of the device is formed by uniformly dispersing microcapsules and electroluminescent powder within the waterborne polyurethane dielectric matrix, which exhibits a reflective contrast ratio of 5.6 and a maximum luminance of 107.5 cd m−2. At the same time, the device possesses the merits of fast response speed at the millisecond level, high‐performance stability, and good mechanical robustness. Besides, through the waveform design, a reflection‐emission hybrid mode is proposed for more diverse display effects. Furthermore, a concept of dual‐mode contrast ratio is established, which further pinpoints the reflection‐emission transition points, thereby prompting the balance between energy‐saving and watching experience. [ABSTRACT FROM AUTHOR]

In recent years, electrophoretic display (EPD) attracts great attention for its ultra‐low power consumption, which is suitable for self‐powered applications. In this case, an energy storage system, simple as the capacitor, is essential for the self‐powered driving of EPDs. However, significance on the capacitor‐based driving of EPDs was underestimated in spite of its great practical value. This paper investigated the capacitor‐based driving of EPD for better performances of self‐powered EPDs. Based on this novel scheme, sports shoes with self‐powered EPD patterns were demonstrated as the future wearable applications. [ABSTRACT FROM AUTHOR]

Wearable displays were recognized as one of the most universal user interface in the future. In this work, our exploration of the functional wearable display is briefly discussed, including a novel driving scheme for alternating current electroluminescence (ACEL) display and some recent studies on the textile EPD devices with different structures. With these results, we may take a step closer to the applicable, reliable wearable displays in the future. [ABSTRACT FROM AUTHOR]

Cloud manufacturing, as a novel service mode in the manufacturing field with the features of flexible resource assignment, timely service, and quantity-based pricing, has attracted extensive attention in recent years. The cloud manufacturing industry uses a significant amount of smart equipment. In this context, equipment maintenance resource scheduling (EMRS) is an important subject that needs to be studied. Cloud manufacturing platforms must provide effective services for equipment maintenance in a timely manner. In order to improve the efficiency of cloud manufacturing platforms and meet the needs of users, an effective EMRS scheme is required. In this paper, we propose a dynamic resource allocation model for cloud manufacturing to meet the needs of users and maximize the benefit of a cloud manufacturing platform. The model takes into account the needs of users and the benefits of a cloud production platform. The contributions of this paper are divided into the following three aspects. First, the E-CARGO model using role-based collaboration theory is introduced to formally model EMRS activities, forming a solvable optimization model. Second, a dynamic pricing model with a center symmetric curve is designed to realize the flexible conversion between time, cost, and price. Third, the concept of satisfaction in fuzzy mathematics is introduced, in order to meet the different needs of users and platforms, in terms of time, price, and cost, while ensuring service quality and the platform's benefits. Finally, an improved genetic algorithm is used to solve the cloud manufacturing resource scheduling problem, and good experimental results are obtained. These results demonstrate that the proposed dynamic pricing model is reasonable, and the allocation scheme obtained through a genetic algorithm is feasible and effective. [ABSTRACT FROM AUTHOR]