Collective dynamics in multi-population Hamiltonian systems

Tian Jing,Ying Jiaqi,Qiao Tianli,Qiu Haibo 한국물리학회 2023 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.82 No.12

In this paper, we investigate measure synchronization (MS) in a two-population network of coupled metronomes system. The system consists of N identical metronomes placed on two swing boards, and the two swings are connected by spring of stifness k. Metronomes on each swing represents a single population. We mainly study the collective dynamics of multipopulation Hamiltonian induced by increased couplings, including inter-population and intra-population couplings. It is found that by tuning K for the inter-population coupling intensity and R for the intra-population coupling intensity, the system reaches various MS states at certain critical coupling intensities, including partial MS and complete MS. The occurrence of partial and complete MS are discussed particularly by analyzing the Poincaré sections of the Hamiltonian system. In addition, we fnd correspondence in between the phase-locking dynamics and various MS transitions.

Corynebacterium defluvii sp. nov., isolated from Sewage

Qiu-Li Yu,Zheng-Fei Yan,Xin He,Feng-Hua Tian,Chuan-Wen Jia,Chang-Tian Li 한국미생물학회 2017 The journal of microbiology Vol.55 No.6

A Gram-positive, aerobic, non-motile, rod-shapeds, cata-lase-positive, and oxidase-negative strain, designated Y49T, was isolated from sewage collected from Jilin Agricultural University, China. It grew at 20–40°C (optimum at 30°C), at pH 6.0–8.0 (optimum at 7.0) and at 0–1.0% sodium chlo-ride (optimum at 0%). The major isoprenoid quinone was menaquinone-8 (MK-8) and the polar lipids were diphos-phatidylglycerol, phosphatidylglycerol, phosphatidylmethy-lethanolamine, four unidentified lipids, and two unidenti-fied aminolipids. The peptidoglycan was meso-diaminopi-melic acid. The cell-wall sugars were galactose, arabinose, and glucose. The fatty acids were C9:0, C16:0, C16:1 ω9c, C17:1 ω9c, C18:3 ω6c (6,9,12), C18:1 ω9c, and C18:0. The DNA G+C content was 51.4 mol%. Based on the 16S rRNA gene se-quence analysis, the nearest phylogenetic neighbors of strain Y49T were Corynebacterium efficiens DSM 44549T (97.5%), Corynebacterium callunae DSM 20147T (97.2%), Coryne-bacterium deserti GIMN 1.010T (96.8%), Corynebacterium glutamicum ATCC 13032T (96.4%), and other species belong-ing to this genus (92.3–95.4%). The DNA-DNA relatedness value between strain Y49T and C. efficiens DSM 44549T, C. callunae DSM 20147T, C. deserti GIMN1.010T, and C. gluta-micum ATCC 13032T was 25.5±2.0%, 21.1±1.0%, 16.5±0.5%, and 13.5±0.9%, respectively. Based on the phylogenetic an-alysis, chemotaxonomic data, physiological characteristics and DNA-DNA hybridization data, strain Y49T represents a novel species of the genus Corynebacterium, for which the name Corynebacterium defluvii sp nov. is proposed. The type strain is Y49T (= KCTC 39731T =CGMCC 1.15506T).

Seismic behavior of steel tube reinforced concrete bridge columns

Tian Tian,Wenliang Qiu,Zhe Zhang 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.28 No.1

This paper reports an experimental study that was accomplished to assess the seismic behavior of steel tube reinforced concrete bridge columns (SBCs). The motivation of this study was to verify a supposition that the core steel tube may be terminated at a rational position in the column to minimize the material cost while maintaining the seismic behavior of this composite column. Four SBC specimens were tested under combined constant axial load and cyclic reversed lateral loads. The unique variable in the test matrix was the core steel tube embedment length, which ranged from 1/3 to 3/3 of the column effective height. It is observed that SBCs showed two distinctly different failure patterns, namely brittle shear failure and ductile flexural failure. Tests results indicate that the hysteretic responses of SBCs were susceptible to the core steel tube embedment length. With the increase of this structural parameter, the lateral strength of SBC was progressively improved; the deformability and ductility, however, exhibited a tendency of first increase and then decrease. It is also found that in addition to maintained the rate of stiffness degradation and cumulative energy dissipation basically unchanged, both the ductility and deformability of SBC were significantly improved when the core steel tube was terminated at the mid-height of the column, and these were the most unexpected benefits accompanied with material cost reduction.

게임 캐릭터로서 맹승(盲僧)의 활용 가능성 모색

구천(Tian Qiu) 한국콘텐츠학회 2021 한국콘텐츠학회논문지 Vol.21 No.8

본 연구는 게임 콘텐츠에서 맹승(盲僧) 캐릭터의 활용 가능성을 모색하고, 그 방안에 대해 제시하는 것을 목적으로 삼는다. 이를 위해 맹승에 관한 문헌 기록을 바탕으로 역사적 변천 과정을 검토하였으며, 한국 문화에서 맹승이 갖는 역사적·문화적 위상을 고찰하였다. 이를 토대로 게임 콘텐츠에서 문화원형으로서 맹승 캐릭터의 가치와 활용 가능성을 검토하고 맹승이 가지고 있는 민속문화적 특징에 따라 캐릭터 창작의 기본 구성 요소를 제안하였다. 그 구체적 내용으로는 맹승 캐릭터 디자인을 할 때 안맹(眼盲)과 개안(開眼) 요소라는 외적 특징과 문무를 겸비한 내적 특징을 결합해야한다고 보았다. 또 맹승에 관한 역사적 기록을 바탕으로 ARPG 장르 게임에서 맹승 모티브를 다루는 게임의 스토리텔링과 메커니즘에 대해 제언하였다. 이러한 연구는 문화원형으로서 맹승 활용 가능성을 모색했다는 점에서, 이를 통해 한국 게임 콘텐츠 기획 및 창작 방법에 있어 단초를 제공할 수 있을 것이다. The purpose of this study is to explore the possibility of using game character Maengseung in game content and to present the method. At first we made a study on the Maengseung’s history and cultural status of Korean folklore. Based on this, we reviewed the value and utilization of the character as a cultural prototype in the game content and proposed the basic components of character creation according to the folk cultural characteristics of the character.

Rational molecular design for isoindigo-based polymer semiconductors with high ductility and high electrical performance

Tian, Fengshou,Chen, Han,Du, Yuchang,Chen, Junhui,Wang, Xiaohong,Lu, Hongbo,Cho, Kilwon,Zhang, Guobing,Qiu, Longzhen The Royal Society of Chemistry 2019 Journal of Materials Chemistry C Vol.7 No.37

<P>Achieving good electrical properties and ductility of polymer semiconductors has always been challenging. In this work, a series of isoindigo derivative-based conjugated polymers was studied in an effort to gain a better understanding of the influence of polymer main and side chain structures on their electrical and mechanical properties. The results suggested that the introduction of alkyl side chains onto the donors can significantly enhance the mechanical properties of isoindigo-based polymers; however, the electrical properties of the films greatly deteriorated due to the large steric hindrance by the chain. The insertion of strong electron-withdrawing units, such as benzodifurandione, into the isoindigo chain during the synthesis of a bis(2-oxoindolin-3-ylidene)-benzodifuran-dione (BIBDF)-based polymer (PBIBDF-BT) significantly boosted the electrical properties of the films without decreasing their mechanical properties. The crack onset in PBIBDF-BT thin films was observed at 50% tensile strain. In addition, PBIBDF-BT thin films exhibited bipolar transport properties with both electron and hole mobilities greater than 0.1 cm<SUP>2</SUP> V<SUP>−1</SUP> s<SUP>−1</SUP> at 100% strain. It is found that the improvement of PBIBDF-BT performance is attributed to its proper molecular structure. The long alkyl side chains significantly increase the ductility of PBIBDF-BT thin films, and the strong electron-withdrawing BIBDF unit in the main chains enhances the local aggregation, resulting in a significant increase in mobility. These results indicate that the mechanical and electrical properties of conjugated polymers could simultaneously be improved through reasonable molecular design.</P>

Modal pushover analysis of self-centering concentrically braced frames

Tian, Li,Qiu, Canxing Techno-Press 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.65 No.3

Self-centering concentrically braced frames (SCCBFs) are emerging as high performance seismically resistant braced framing system, due to the capacity of withstanding strong earthquake attacks and promptly recovering after events. To get a further insight into the seismic performance of SCCBFs, systematical evaluations are currently conducted from the perspective of modal contributions. In this paper, the modal pushover analysis (MPA) approach is utilized to obtain the realistic seismic demands by summarizing the contribution of each single vibration mode. The MPA-based results are compared with the exact results from nonlinear response history analysis. The adopted SCCBFs originate from existing buckling-restrained braced frames (BRBF), which are also analyzed for purpose of comparison. In the analysis of these comparable framing systems, interested performance indices that closely relate to the structural damage degree include the interstory drift ratio, floor acceleration, and absorbed hysteretic energy. The study shows that the MPA approach produces acceptable predictions in comparison to the exact results for SCCBFs. In addition, the high-modes effect on the seismic behavior increases with the building height, and is more evident in the SCCBFs than the BRBFs.

Supplementation of Clostridium butyricum Alleviates Vascular Inflammation in Diabetic Mice

Tian Zhou,Shuo Qiu,Liang Zhang,Yangni Li,Jing Zhang,Donghua Shen,Ping Zhao,Lijun Yuan,Lianbi Zhao,Yunyou Duan,Changyang Xing 대한당뇨병학회 2024 Diabetes and Metabolism Journal Vol.48 No.3

Background: Gut microbiota is closely related to the occurrence and development of diabetes and affects the prognosis of diabetic complications, and the underlying mechanisms are only partially understood. We aimed to explore the possible link between the gut microbiota and vascular inflammation of diabetic mice.Methods: The <i>db/db</i> diabetic and wild-type (WT) mice were used in this study. We profiled gut microbiota and examined the and vascular function in both <i>db/db</i> group and WT group. Gut microbiota was analyzed by 16s rRNA sequencing. Vascular function was examined by ultrasonographic hemodynamics and histological staining. Clostridium butyricum (CB) was orally administered to diabetic mice by intragastric gavage every 2 days for 2 consecutive months. Reactive oxygen species (ROS) and expression of nuclear factor erythroid-derived 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were detected by fluorescence microscopy. The mRNA expression of inflammatory cytokines was tested by quantitative polymerase chain reaction.Results: Compared with WT mice, CB abundance was significantly decreased in the gut of <i>db/db</i> mice, together with compromised vascular function and activated inflammation in the arterial tissue. Meanwhile, ROS in the vascular tissue of <i>db/db</i> mice was also significantly increased. Oral administration of CB restored the protective microbiota, and protected the vascular function in the <i>db/db</i> mice via activating the Nrf2/HO-1 pathway.Conclusion: This study identified the potential link between decreased CB abundance in gut microbiota and vascular inflammation in diabetes. Therapeutic delivery of CB by gut transplantation alleviates the vascular lesions of diabetes mellitus by activating the Nrf2/HO-1 pathway.

Measure Synchronization and Phase Coherence in a High Dimensional Hamiltonian System

Jing Tian,Bo Li,Haibo Qiu 한국물리학회 2019 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.74 No.8

Partial and complete measure synchronizations (MSs) are investigated in a high-dimensional Hamiltonian system. Here, a four-coupled ring-shaped rotor model is employed. We calculate the averaged energy of each rotor numerically to address the clustering process of measure synchronization. Poincar\'e sections are used to analyze the dynamic mechanism of partial MS and complete MS transitions, and the separatrix crossing is revealed to be the dynamical mechanism behind all different MS transition behaviors. By calculating the averaged frequency of each rotor, we explore the relationship between frequency locking and MS, and reveal a one-to-one correspondence. Furthermore, we find that abrupt changes in global or even partial phase coherence between the phase oscillators can be an indicator for MS transitions, albeit full phase coherence is not equivalent to measure synchronization.

Modal pushover analysis of self-centering concentrically braced frames

Li Tian,Canxing Qiu 국제구조공학회 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.65 No.3

Self-centering concentrically braced frames (SCCBFs) are emerging as high performance seismically resistant braced framing system, due to the capacity of withstanding strong earthquake attacks and promptly recovering after events. To get a further insight into the seismic performance of SCCBFs, systematical evaluations are currently conducted from the perspective of modal contributions. In this paper, the modal pushover analysis (MPA) approach is utilized to obtain the realistic seismic demands by summarizing the contribution of each single vibration mode. The MPA-based results are compared with the exact results from nonlinear response history analysis. The adopted SCCBFs originate from existing buckling-restrained braced frames (BRBF), which are also analyzed for purpose of comparison. In the analysis of these comparable framing systems, interested performance indices that closely relate to the structural damage degree include the interstory drift ratio, floor acceleration, and absorbed hysteretic energy. The study shows that the MPA approach produces acceptable predictions in comparison to the exact results for SCCBFs. In addition, the high-modes effect on the seismic behavior increases with the building height, and is more evident in the SCCBFs than the BRBFs.

Measure Synchronization in a Huygens’s Non-Dissipative Two-Pendulum Clocks System

Jing Tian,ZiChen Chen,HaiBo Qiu,XiaoQiang Xi 한국물리학회 2018 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.72 No.2

In this paper, we characterize measure synchronization (MS) in a four-degrees-of-freedom Huygens’s two-pendulum clocks system. The two-pendulum clocks are connected by a massless spring with stiffness constant k. We find that with the stiffness constant k increasing, the coupled pendulums system achieves MS above a threshold value of kc. The energy characteristics of measure synchronization have been discussed, it is found that averaged energy of each pendulum system provide us an easy way to characterize MS transition. Furthermore, we discuss the dependence of the critical value for MS transition on initial conditions and the characteristic parameters of the system.