A New Control Strategy for Input Voltage Sharing in Input Series Output Independent Modular DC-DC Converters

Yang, Wei,Zhang, Zhijie,Yang, Shiyan The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.3

Input series output independent (ISOI) dc-dc converter systems are suitable for high voltage input and multiple output applications with low voltage rating switches. This paper proposes a novel control strategy consisting of one output voltage regulating (OVR) control loop and n-1 (n is the number of modules in the ISOI system) input voltage sharing (IVS) control loops. An ISOI system with the proposed control strategy can be applied to applications where the output loads of each module are the same. Under these conditions, IVS can be achieved and output voltages copying can be realized in an ISOI system. In this control strategy there is only one controller for each module and the design process of the control loops is simple. Since no central controller is needed in the system, modularity of the system is improved. The operation principle of the new control strategy is introduced and the control effect is simulated. Then the output power and voltage characteristics of an ISOI system under this new control strategy are analyzed. The stability of the proposed control strategy is explored base on a Hurwitz criterion, and the design guide line of the control strategy is given. A two module ISOI system prototype is fabricated and tested in the laboratory. Experimental results verify the effectiveness of the proposed control strategy.

A Variational Pragmatic Study of the Speech Act of Apology in Irish English

Shiyan Yang,Se-Eun Jhang,Yaochen Deng 한국코퍼스언어학회 2020 Corpus Linguistics Research Vol.6 No.2

This article takes a variational pragmatic approach to formulae of apology in Irish English by comparing the speech of the speakers from Northern Ireland and that of the speakers from the Republic of Ireland. Using the Irish component of the International Corpus of English (ICE-Ireland) as a basis, the analysis centers on the different patterns of apology between these two regions not only in the frequency of occurrence and the types of apology, but also in the contextual constraints on the use of apology. Results indicate that there is no significant difference between the two regions whether in the frequency of occurrence or in the types of apology formulae. However, contexts are found to exert significant effect on the use of apology formulae. In public and institutional contexts, particularly those related to legal and political systems, the formulae of apology are much more frequently used in Northern Ireland than in the Republic of Ireland, which supports the hypothesis that political borders influence the choice of language use as proposed in previous studies.

A New Control Strategy for Input Voltage Sharing in Input Series Output Independent Modular DC-DC Converters

Wei Yang,Zhijie Zhang,Shiyan Yang 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.3

Input series output independent (ISOI) dc-dc converter systems are suitable for high voltage input and multiple output applications with low voltage rating switches. This paper proposes a novel control strategy consisting of one output voltage regulating (OVR) control loop and n-1 (n is the number of modules in the ISOI system) input voltage sharing (IVS) control loops. An ISOI system with the proposed control strategy can be applied to applications where the output loads of each module are the same. Under these conditions, IVS can be achieved and output voltages copying can be realized in an ISOI system. In this control strategy there is only one controller for each module and the design process of the control loops is simple. Since no central controller is needed in the system, modularity of the system is improved. The operation principle of the new control strategy is introduced and the control effect is simulated. Then the output power and voltage characteristics of an ISOI system under this new control strategy are analyzed. The stability of the proposed control strategy is explored base on a Hurwitz criterion, and the design guide line of the control strategy is given. A two module ISOI system prototype is fabricated and tested in the laboratory. Experimental results verify the effectiveness of the proposed control strategy.

Carcass Fat-free Lean Gain of Chinese Growing-finishing Pigs Reared on Commercial Farms

Yang, Libin,Li, Defa,Qiao, Shiyan,Gong, Limin,Zhang, Defu Asian Australasian Association of Animal Productio 2002 Animal Bioscience Vol.15 No.10

Five regions and 258 pigs were selected for this study: North (Beijing), Central (Wuhan), South (Guangzhou), Southwest (Chongqing), Northeast (Harbin). Five typical genetics of growing-finishing pig were selected: Landrace${\times}$Large White${\times}$Beijing Black, Duroc${\times}$Landrace${\times}$Large White, Duroc${\times}$Large White${\times}$Landrace, Landrace${\times}$Rongchang, Landrace${\times}$Harbin White, respectively at each sites. The basal diet was a corn-soybean meal containing sufficient nutrients to meet requirements. Carcass fat-free lean gain was determined by dissecting and analyzing chemical composition of the carcass. Cubic function fitted lean moistures to live weights better than other functions. Exponential function fitted lean lipids to live weights equally to allometric function. Carcass fat-free lean gain of Duroc${\times}$Large White${\times}$Landrace, Landrace${\times}$Large White${\times}$Beijing Black, Duroc${\times}$Landrace${\times}$Large White, Landrace${\times}$Harbin White, Landrace${\times}$Rongchang from 20 to 100 kg of average body weight was 259 g/d, 261 g/d, 311 g/d, 220 g/d, 200 g/d, respectively. All are lower than intermediate fat-free lean gain in NRC (1998).

Gate-tunable phase transitions in thin flakes of 1T-TaS2.

Yu, Yijun,Yang, Fangyuan,Lu, Xiu Fang,Yan, Ya Jun,Cho, Yong-Heum,Ma, Liguo,Niu, Xiaohai,Kim, Sejoong,Son, Young-Woo,Feng, Donglai,Li, Shiyan,Cheong, Sang-Wook,Chen, Xian Hui,Zhang, Yuanbo Nature Pub. Group 2015 Nature nanotechnology Vol.10 No.3

<P>The ability to tune material properties using gating by electric fields is at the heart of modern electronic technology. It is also a driving force behind recent advances in two-dimensional systems, such as the observation of gate electric-field-induced superconductivity and metal-insulator transitions. Here, we describe an ionic field-effect transistor (termed an iFET), in which gate-controlled Li ion intercalation modulates the material properties of layered crystals of 1T-TaS2. The strong charge doping induced by the tunable ion intercalation alters the energetics of various charge-ordered states in 1T-TaS2 and produces a series of phase transitions in thin-flake samples with reduced dimensionality. We find that the charge-density wave states in 1T-TaS2 collapse in the two-dimensional limit at critical thicknesses. Meanwhile, at low temperatures, the ionic gating induces multiple phase transitions from Mott-insulator to metal in 1T-TaS2 thin flakes, with five orders of magnitude modulation in resistance, and superconductivity emerges in a textured charge-density wave state induced by ionic gating. Our method of gate-controlled intercalation opens up possibilities in searching for novel states of matter in the extreme charge-carrier-concentration limit.</P>

An Interleaved Converter for 12-pulse Rectifier Harmonic Suppression

Li, Yuan,Yang, Wei,Cang, Sheng,Yang, Shiyan The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.5

In order to further improve the harmonic suppression capability of conventional 12-pulse rectifiers, this paper proposes a low harmonic 12-pulse rectifier using an Active Inter-Phase Reactor (AIPR). Through a detailed analysis of the relationship between the input current, output current and circulating current of the DC side, the mechanism where the AC grid side current harmonics can be suppressed by the DC side circulating current is revealed. On this basis, an interleaved APFC controlled by a DSP is designed and used as an AIPR along with an interphase reactor. A simulation is carried out with MATLAB/Simulink and an experiment is performed on a 9-kVA prototype. The obtained results verify the feasibility and validity of the proposed approach. Compared with a traditional 12-pulse rectifier, the THD can be reduced to 1/5 of the original value, and the capacity of the AIPR is only 2% of the load power. Thus, it is suitable for high-power applications.

An Interleaved Converter for 12-pulse Rectifier Harmonic Suppression

Yuan Li,Wei Yang,Sheng Cang,Shiyan Yang 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.5

In order to further improve the harmonic suppression capability of conventional 12-pulse rectifiers, this paper proposes a low harmonic 12-pulse rectifier using an Active Inter-Phase Reactor (AIPR). Through a detailed analysis of the relationship between the input current, output current and circulating current of the DC side, the mechanism where the AC grid side current harmonics can be suppressed by the DC side circulating current is revealed. On this basis, an interleaved APFC controlled by a DSP is designed and used as an AIPR along with an interphase reactor. A simulation is carried out with MATLAB/Simulink and an experiment is performed on a 9-kVA prototype. The obtained results verify the feasibility and validity of the proposed approach. Compared with a traditional 12-pulse rectifier, the THD can be reduced to 1/5 of the original value, and the capacity of the AIPR is only 2% of the load power. Thus, it is suitable for high-power applications.

Pea starch increases the dry matter flow at the distal ileum and reduces the amino acids digestibility in ileal digesta collected after 4 hours postprandial of pigs fed low-protein diets

Zhou Junyan,Wang Lu,Yang Guangxin,Yang Lijie,Zeng Xiangfang,Qiao Shiyan 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.7

Objective: The study was aimed to investigate the rules of postprandial changes in intestine digesta dry matter (DM) flow and amino acid digestibility of growing pigs fed low-protein (LP) diets made of different starch. Methods: Eight barrows (28.8±2.1 kg) with a T-cannula at the distal ileum were randomly allotted to an 8×3 Youden square design. Treatments included: waxy corn starch LP (WLP); corn starch LP (CLP) and pea starch LP (PLP). Diets were given at 08:00 and 20:00. Digesta samples were collected in six 2-h stages from 08:00 to 20:00. Results: The Cr concentrations of ileal digesta increased and then decreased in WLP and CLP, while increased continuously in PLP as time passed after postprandial (p<0.05). Higher average Cr concentrations (0.78% and 0.84% vs 0.70%; p<0.05) and lower average DM flow (181.1 g/kg and 166.3 g/kg vs 240.3 g/kg; p<0.001) were observed in WLP and CLP, compared with PLP. The apparent ileal digestibility coefficient of most amino acids in WLP and CLP increased compared with that in PLP. No difference in lysine or methionine digestibility was observed. When digesta were collected in 2-h periods, the apparent ileal digestibility coefficient of amino acids did not change over time. When digesta was collected in 4-h periods from 16:00 to 20:00 and 6-h periods from 14:00 to 20:00 (p<0.05), WLP and CLP showed markedly higher amino acid digestibility than PLP Conclusion: High-amylose slowly digested starch can increase the DM flow at the distal ileum and reduce the apparent ileal digestibility coefficient of amino acids of pigs fed LP diets. Compared with waxy corn starch and corn starch, pea starch reduced the digestibility of amino acids in digesta collected after 4 h postprandial. Objective: The study was aimed to investigate the rules of postprandial changes in intestine digesta dry matter (DM) flow and amino acid digestibility of growing pigs fed low-protein (LP) diets made of different starch.Methods: Eight barrows (28.8±2.1 kg) with a T-cannula at the distal ileum were randomly allotted to an 8×3 Youden square design. Treatments included: waxy corn starch LP (WLP); corn starch LP (CLP) and pea starch LP (PLP). Diets were given at 08:00 and 20:00. Digesta samples were collected in six 2-h stages from 08:00 to 20:00.Results: The Cr concentrations of ileal digesta increased and then decreased in WLP and CLP, while increased continuously in PLP as time passed after postprandial (p<0.05). Higher average Cr concentrations (0.78% and 0.84% vs 0.70%; p<0.05) and lower average DM flow (181.1 g/kg and 166.3 g/kg vs 240.3 g/kg; p<0.001) were observed in WLP and CLP, compared with PLP. The apparent ileal digestibility coefficient of most amino acids in WLP and CLP increased compared with that in PLP. No difference in lysine or methionine digestibility was observed. When digesta were collected in 2-h periods, the apparent ileal digestibility coefficient of amino acids did not change over time. When digesta was collected in 4-h periods from 16:00 to 20:00 and 6-h periods from 14:00 to 20:00 (p<0.05), WLP and CLP showed markedly higher amino acid digestibility than PLPConclusion: High-amylose slowly digested starch can increase the DM flow at the distal ileum and reduce the apparent ileal digestibility coefficient of amino acids of pigs fed LP diets. Compared with waxy corn starch and corn starch, pea starch reduced the digestibility of amino acids in digesta collected after 4 h postprandial.