Novel filter approach for ripple‑free input current boost converters based on variable inductors

He Liu,Lu Qu,Qiang Tong,Gaozhi Jia 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.7

A coupled inductor filter (CIF) is a good candidate for reducing current ripple, and improving the power density of switching power. However, because the resonance frequency of its series branch is easily affected by non-ideal factors, such as the inductance production process, ambient temperature, device aging, among others, it is usually unable to optimize its effect in practice. To solve this problem, by considering the ripple-free input current boost converter as an example, this paper proposes a novel method that adds a variable inductor (VI) into the AC resonant branch of a CIF. The value of the VI is adjusted online to optimize the ripple cancellation effect by comparing the peak-to-peak current ripples in the main power inductor and the AC branch inductor. In the aforementioned scheme, the voltage-controlled current source (VCCS) in the closed loop control circuit is critical for achieving a rapid and stable regulation of the VI. Therefore, a 1/∛s compensator is adopted to provide a sufficient stability margin under various operating conditions. Finally, the input characteristics of a 500 W boost converter are measured and presented in this study. The obtained results demonstrate that the total inductor current ripple peak-to-peak values at each operating point are within 85 mA, which confirms the correctness of the theoretic analyses.

논문(論文) : 論漢語詞彙與構式的綜合敎學 -作爲二語的漢語詞彙敎學的新思路

( Jia Jun Tao ),( Qing He Lu ) 중국어문연구회 2013 中國語文論叢 Vol.0 No.60

The thesis fully investigates the errors made by foreign students who study Chinese from the view point of Construction Grammar. It finds out some common errors such as “same words with different construction”, “different words with same construction”, “different words with similar construction” and “different words with same meaning but different construction”. These errors are thought to be the result of inter language and the authors proposed a new synthetical language teaching method that is to combine lexicon and construction grammar. The thesis analyzes the differences between this new teaching method and the traditional method centering on sentence structure. It discusses the principles of this synthetical teaching method based on lexicon and Construction Grammar and the role and position of this new teaching method in the systematic teaching of Chinese lexicon.

Research on the Impact of China’s High-Speed Railway Construction on Regional Economy-Take Xibao High-Speed R ail as an Example-

He, Jia(하가),Chen, Lu(션루),Zhang, Meng-Ze(장몽택),Bae, Ki-Hyung(배기형) 한국물류학회 2019 물류학회지 Vol.29 No.5

서보(西寶) 고속철도는 산시성(陕西省) 서안(西安)에서 보계(寶雞)까지 산시성 관중(關中) 지역에 있다. 서보 고속철도는 국가 중점 철도 인프라 건설 프로젝트이고 서안, 함양(鹹陽), 보계, 양릉시범구(楊淩示範區)를 지나며 서안북(西安北), 함양진도(鹹陽秦都), 양릉남(楊淩南), 기산(岐山)과 보계남(寶雞南) 등 5개 역이 있다. 본문은 고속철도는 지역 경제 발전에 미치는 영향에 관한 이론과 문헌을 고찰하여 고속철도 발전이 지역 경제 발전에 관련 메커니즘을 요약하였다. 이를 바탕으로 본문은 서보 고속철도를 대상으로 DID모델을 사용하여 서보고속 철도가 연선 지역의 경제 발전에 미치는 영향을 실증 분석을 실행하였다. 연구 결과에 따르면 서보 고속철도는 연선의 경제 성장을 촉진하는 데 중요한 역할을 한다. 따라서 고속철도는 철도 연선 지역 경제 발전을 촉진하는 데 중요한 역할을 한다는 결론을 내릴 수 있고 고속철도의 건선은 연선 지역의 경제 발전에 큰 도움이 된다는 것을 알 수 있다. 또한 본문은 산시성 고속철도 건설에 대한 정책적 조언과 고속철도 건설을 가속화하기 위한 제안도 제시하였다. Xibao High-speed Railway is located in Guanzhong area of S haanxi Province, from Xi’an City in Shaanxi Province to Baoji City in Shaanxi Province in the west. It passes through Xi’an, Xianyang, Baoji and Yangling Demonstration Zones. There are five stations in the whole line, including Xi’an North Station and Xianyang. Qindu Station, Yangling South Station, Qishan Station, Baoji South Station, and Xibao High-speed Railway are key national railway infrastructure construction projects. The paper summarizes the relevant theories and literatures of the impact of high-speed rail on regional economic development, and summarizes the relevant mechanisms of high-speed rail development on regional economic development. By using Xibao high-speed rail as an example, the DID model is used to study the area along the Xibao high-speed railway. The impact of economic development has found that Xibao High-speed Railway has a significant role in promoting economic growth along the route. Therefore, it is concluded that high-speed rail has an important role in promoting and promoting the economic development along the line. The construction of high-speed rail will be of great help to the regional economic development along the line. Finally, relevant policy recommendations were put forward for the construction of high-speed railways in Shaanxi Province, and relevant suggestions for accelerating the construction of high-speed railways in Shaanxi Province were put forward.

Distinct Electronic Structure for the Extreme Magnetoresistance in YSb

He, Junfeng,Zhang, Chaofan,Ghimire, Nirmal J.,Liang, Tian,Jia, Chunjing,Jiang, Juan,Tang, Shujie,Chen, Sudi,He, Yu,Mo, S.-K.,Hwang, C. C.,Hashimoto, M.,Lu, D. H.,Moritz, B.,Devereaux, T. P.,Chen, Y. L American Physical Society 2016 Physical Review Letters Vol.117 No.26

A Study on the Industrial Relationship and Economic Ripple Effects of China's Railway Transport Industry

He, Jia,Chen, Lu,배기형 한국유통경영학회 2020 유통경영학회지 Vol.23 No.3

Purpose: As an important part of the Chinese comprehensive transportation system, railway transportation has a pillar role in the national economy. On the one hand, it transports raw materials, fuels and other intermediate products for all industrial sectors of the national economy. On the other hand, it has played a positive role in the exchange of talents and technologies between various industries. It has a considerable driving and pulling effect on various industries of the national economy. Research design, data, and methodology: Through literature research, empirical research and other research methods, the relationship between the railway transportation industry and other industries across the country is expounded. Results: First of all, a series of indicators of industrial correlation are calculated, and it is concluded that the railway transport industry belongs to the intermediate input basic industry; then, through the investigation of the value composition of the railway transport industry, it is concluded that the railway transport industry has high labor costs and belongs to capital-intensive industries; then, the economic ripple effect of the railway transport industry is analyzed. It is concluded that the differential operation of the separation of passengers and goods should be carried out according to the characteristics of railway passenger and freight transportation. Finally, based on the regression analysis of the relationship between China's railway passenger and freight volume and GDP from 2001 to 2017, it is concluded that the railway transport industry plays a promoting role in the national economy. Conclusions: Through the calculation results, it can be seen that China's railway transportation industry plays an important role in promoting national economic growth and inter-industry integration, and in order to ensure sustained economic stability, China should continue to consolidate the basic industrial position of railway transportation industry and better promote economic development.

Hot deformation behavior of CNTs/Al-Li composite prepared by powder metallurgy

Jia Lei,Liu Yang,Xing Zhiguo,He Gengchao,Lu Zhenlin,Zhou Yongxin 한국탄소학회 2022 Carbon Letters Vol.32 No.5

CNTs/Al-Li composite was first prepared by hot-pressed sintering from Al-Li alloy powder and CNTs solution, and then the hot compression tests were performed on MMS-100 thermal simulator at strain rate range of 0.01– 10 s−1, deformation temperature range of 350–500 °C, and total deformation amount of 60%. True stress–strain curves were plotted, and constitutive equation as well as hot processing maps were successfully confirmed based on Arrhenius constitutive model and Prasad instability criterion. Results show that CNTs/Al-Li composite have a very poor hot deformation ability and narrow processing region, which is strain rate range of 0.1–1 s−1 and deformation temperature range of 360–400 °C. Hot extrusion experiment was carried out and the processing parameters were selected according to the established hot processing map, and an improvement on strength and a good balance between strength and plasticity can be obtained, which is about 650 MPa for tensile strength and 9% for elongation.

A Shortcut to the Preparation of Naturally Occurring Arbutin

Jia-Lu Xue,Jin-Wei Yang,Qiong Deng,Xiao-Peng He,Guo-Rong Chen 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.7

A Shortcut to the Preparation of Naturally Occurring Arbutin

Xue, Jia-Lu,Yang, Jin-Wei,Deng, Qiong,He, Xiao-Peng,Chen, Guo-Rong Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.7

Research on the Evaluation and Promotion Plan of Competitiveness of Chinese Cultural and Creative Industries - Taking Provinces and Cities Along the “Belt and Road” As an Example

Chen Lu,He Jia,Bae Ki-Hyung 한국콘텐츠학회 2020 International Journal of Contents Vol.16 No.3

With the rapid growth of high-tech, the development of cultural and creative industries has gradually become the focus of national industrial development. With the proposal of China’s “Belt and Road” strategy, the role of cultural and creative industries in the provinces and cities along the “Belt and Road” in the entire international trade is becoming increasingly critical. It is necessary to explore solutions to improve the competitiveness of China’s cultural and creative industries, factoring the surrounding cities of the “Belt and Road” as an example. Thus, this paper proposes the six-element diamond model based on innovation capability and government support to render a comprehensive evaluation of the competitiveness of the cultural and creative industries in the 31 provinces and cities across the country. The results show that the overall competitiveness of the 18 provinces and cities along the “Belt and Road” cultural and creative industries is weak. Focusing on the 18 provinces and cities along the “Belt and Road”, using the linear regression measurement model quantitative analysis, the four types of influencing factors affecting the development of the competitiveness of cultural and creative industries along the “Belt and Road” were obtained. Finally, according to the four types of influence, the competitiveness improvement plan is proposed from the four aspects: government role, consumption preference, industrial innovation ability, and the introduction of highquality talent.

Characterization of Ecdysteroid UDP-Glucosyltransferase Gene Promoter from Bombyx mori Nucleopolyhedrovirus

Xing-Jia Shen,Yong-Zhu Yi,Shun-Ming Tang,Zhi-Fang Zhang,Yi-Ren Li,Jia-Lu He,Xiang-Fu Wu 한국잠사학회 2004 International Journal of Industrial Entomology Vol.8 No.2

Bombyx mori nucleopolyhedrovirus (BmNPV) ecdysteroid UDP-glucosyltransferase gene (egt) promoter fragments of different lengths were amplified from BmNPV ZJ-8 genomic DNA by PCR. Reporter plasmids pBmegt542-luc, pBmegt309-luc and pBmegt159- luc with luciferase (luc) driven by egt promoters were constructed. Both in vitro and in vivo expressions showed that BmNPV egt promoter activity requires the transactivation of viral factor(s), and expression of luc was detected earliest at 24 hrs post infection (pi). BmNPV ZJ-8 homologous region 3 (hr3) increased the expression of luc by over 1,600-fold. Molting hormone of 1.0 ~ 2.0 mg/ml can dramatically down regulate expression of luc. Juvenile hormone analogue of 0.5 ~ 2.0 mg/ml increased expression of luc by 145.8% to 75.7%. Deletion assay revealed that the promoter fragment of 159 bp contains the basal promoter structure; Promoter fragments of 309 bp and 542 bp showed similar but much higher transcriptional activities than that of 159 bp, suggesting that nucleotide from -159 to -309 nt upstream the translation initiation site harbors the main cis-acting elements.