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Prehistoric human cultural sites along the eastern coast of Fujian Province are important records for studying the origin and spread of the Austronesian civilization. The Huangqiyu site is the first Tanshishan culture site to be unearthed in the Min River estuary area and was excavated by scientific archeology. It has great significance for further research of the Tanshishan culture and the coupled relationship between prehistoric human activities and environmental changes in the Fujian coastal region. The chronology of archeological sites is an important foundation for prehistoric archeology. In this study, the burial age of the Huangqiyu site in Lianjiang County was analyzed using the Optically Stimulated Luminescence (OSL) dating technique on the basis of Accelerator Mass Spectrometry (AMS) 14C dating. In the field, the T2 section of the Huangqiyu site was selected for sampling, and the single-aliquot regeneration dose method of medium-grained quartz was used to assess OSL chronology in the laboratory. The results showed that the OSL burial age of the Huangqiyu site ranges from approximately 8.5 ± 0.5 to 4.4 ± 0.2 ka, corresponding to the sedimentary/cultural strata of the early Middle Holocene. The OSL age of sample 2019118, which was consistent with the AMS 14C age, was 4.4 ± 0.2 ka, corresponding roughly to the Tanshishan culture. The age of sample 2019117 was 5.4 ± 0.3 ka, which may be an overestimation because the equivalent dose of this sample showed a weakly skewed distribution with a tail at the high value end, indicating that there was a small amount of sundry particles and that the drying was insufficient. This problem may have led to a bias in the measured equivalent dose and, in turn, to overestimation of the age of the sample. The age of sample 2019119, which was affected by the sampling environment, was 8.5 ± 0.5 ka, possibly indicating the maximum age of the bottom boundary of the site. Archeological studies have found that the age indicated by the pottery features excavated from the cultural layer at the bottom of the Huangqiyu site is most likely earlier than the Tanshishan culture, or possibly that of the lower strata of the Tanshishan culture. Overall, the ages of samples 2019117 and 2019119 are different from the AMS 14C ages, but these are consistent with the archeological characteristics of the site. By comparing the geomorphological and environmental evolution process of the Fuzhou Basin, where the Huangqiyu site is located, with the regional prehistoric human activities, it was found that the site corresponds to the warm climate of 6 500-4 000 a B P and relatively a high sea level period. Many prehistoric remains were developed in the Fuzhou Basin during this period, and the prosperous Tanshishan culture and the lower Tanshishan culture emerged in the region. At the end of the Neolithic age, the abrupt cold event of 4.2-4.0 ka, the drastic change of climate and environment in the tropical and subtropical regions on both sides of the Pacific Ocean at 4 000-3 000 a B P, and the invasion of the northern Wu-Yue culture may explain the disappearance of the follow-up culture. Because of the limited precision of the regional sea-level change curve, it is insufficient to discuss sea-land change and the coupled relationship with human activities. Relevant studies need to strengthen these aspects in the future.

Aiming at the problems of high performance，high requirements and difficult processing of power electronic device driving pulse signal，a high performance pulse signal processing circuit module is designed and fabricated, and the design is completed by EDA high speed circuit technology. LTspice simulates the circuit system and conducts experimental test. Compared with the domestic research status, the test index has been significantly improved. The high-speed pulse forward rectification of 1 MHz is realized, the output level is controllable, the pulse width adjustment range is 20% to 60%, and the upper and lower edge time is controlled within 25 ns, wherein the falling edge time as low as 13 ns, the transmission delay adjustment range is 20 ns to 110 ns, and the 2 MHz pulse signal indicators are also greatly improved, thereby effectively improving the efficiency of the drive circuit and the main circuit. Further optimizing the selection and layout of the device and adopting a more sophisticated manufacturing process, it is expected to process pulse signals with a frequency of up to 5 MHz, making the power electronic circuit more integrated and efficient.

The following three systems of the amorphous alloy specimens have been prepared and measured: Nd x B 20− x (Fe 78 Co 1.7 Cu 0.3 ) ( x = 0, 1, 2, 3, 5), Sm x B 20− x (Fe 78 CO 17 Cu 0.3 ( x = 0, 1, 3), Fe 79.7− x Co x (Cu 0.3 B 17 Sm 3 ) ( x = 0, 1.7, 3.7, 5.7, 7.7). The results show that the specific magnetizing moment σ s varies with temperature T , and that the anisotropy constant K u and saturation magnetostriction constant λ s vary with composition x at room temperature. It is shown that small amounts of rare earth elements alloyed into Fe-based amorphous alloys can increase K u , λ s and the crystallization temperature T cr of the amorphous alloys. It stands to reason that the local magnetic anisotropy and the exchange interaction are both effected. Although σ s and T c may decrease as the small amount of R elements is alloyed, they can be compensated with an increase in the composition of Co.

A comprehensive test strategy initiated as early into the design cycle as possible can yield significant improvement in test coverage, faster fault diagnosis, lowered test and development costs, shorter system development time, and faster time to market. One means of improving the testability of systems is to adopt a structured, hierarchical design methodology, and a corresponding hierarchical test methodology. This paper would introduce the implementation of hierarchical design for testability (DFT) methodology from three ways: hierarchical structure, hierarchical test buses based on MIL-STD-1553B, IEEE 1149.5, and IEEE 1149.1, and concurrent test engineering.