A Unifi ed Theory for Distortion Analysis of Thin-Walled Hollow Sections

Xun Xu,Huawen Ye,De-Yi Zhang,Shizhong Qiang 한국강구조학회 2019 International Journal of Steel Structures Vol.19 No.3

A novel unifi ed theory for distortion analysis of thin-walled hollow section has been proposed based on the Hellinger– Reissner variational principle to account for distortional shear deformation eff ects. Based on the proposed theory, a fi nite segment model has been developed and the method for determining the distortion functions of the cross-section has been proposed. The rationality of approaches for determining distortional shear stress has been analysed and it is concluded that Bredt’s pure distortion does not exist in the single-cell hollow section. Comparisons and analyses have been performed between the proposed theoretical model and the existing four groups of theories in distortion analysis of thin-walled hollow section. Eff ects of distortional warping shear stress on the shear deformation has been investigated and the results indicate that the distortional shear deformation eff ect results in a decrease of the distortional warping stresses and shear stresses but an increase of the transverse bending stresses. The numerical study indicates that the distortional shear deformation eff ects can be ignored and the fi rst derivative of the distortion angle can be employed as the distortional warping function for the conventional hollow sections of bridge structures.

Individualized Cookery on How to Improve Farmhouse Cuisine

Xu Xun(徐迅) 세계문화관광학회 2008 Conference Proceedings Vol.9 No.0

Being one of the typical forms of developing rural tourism, "Happy farmhouse activities" is characterized by "eating local food, staying in the farmhouse, working on the farmland, appreciating scenery of the countryside and enjoying happy rural life". And the first priority is "eating". While the fact is that the quality of the dishes served needs improvement. This article elaborates on how to improve the quality of the local cuisine by cooking in accordance with the choice of "chefs, ingredients and vessel". It also states that rural tourism can be further developed if those local restaurants intend to improve themselves. "农家乐"是乡村旅游发展的一种典型形式,以"吃农家饭、住农家屋、干农家活、赏农家景、享农家乐"为主要特色,"吃"是农家乐的第一要素。当前农家乐的菜肴品质存在不少问题,亟需得到提升。本文以"人材、物材、器材"三材为着眼点,阐述如何通过因材施艺,来提升"农家乐"菜肴的品质。解决好"吃农家饭""问题,将有助于"农家乐"旅游的进一步发展。

Smart Manufacturing with a Decentralized and Distributed Regime

Xun Xu 한국생산제조학회 2024 한국생산제조시스템학회 학술발표대회 논문집 Vol.2024 No.4

Controlling Major Cellular Processes of Human Mesenchymal Stem Cells using Microwell Structures

Xu, Xun,Wang, Weiwei,Kratz, Karl,Fang, Liang,Li, Zhengdong,Kurtz, Andreas,Ma, Nan,Lendlein, Andreas Wiley (John WileySons) 2014 Advanced healthcare materials Vol.3 No.12

<P>Directing stem cells towards a desired location and function by utilizing the structural cues of biomaterials is a promising approach for inducing effective tissue regeneration. Here, the cellular response of human adipose-derived mesenchymal stem cells (hADSCs) to structural signals from microstructured substrates comprising arrays of square-shaped or round-shaped microwells is explored as a transitional model between 2D and 3D systems. Microwells with a side length/diameter of 50 관m show advantages over 10 관m and 25 관m microwells for accommodating hADSCs within single microwells rather than in the inter-microwell area. The cell morphologies are three-dimensionally modulated by the microwell structure due to differences in focal adhesion and consequent alterations of the cytoskeleton. In contrast to the substrate with 50 관m round-shaped microwells, the substrate with 50 관m square-shaped microwells promotes the proliferation and osteogenic differentiation potential of hADSCs but reduces the cell migration velocity and distance. Such microwell shape-dependent modulatory effects are highly associated with Rho/ROCK signaling. Following ROCK inhibition, the differences in migration, proliferation, and osteogenesis between cells on different substrates are diminished. These results highlight the possibility to control stem cell functions through the use of structured microwells combined with the manipulation of Rho/ROCK signaling.</P>

조선족의 두만강, 압록강 뗏목소리에 대한 연구

허휘훈(Xu Hui-xun) 아시아강원민속학회 2009 江原民俗學 Vol.23 No.-

??조선족 뗏목소리의 역사 문화적 배경과 그 존재양상 그리고 조선족 뗏목소리의 사설 내용과 가장형태 등에 대해 살펴보았다. 이를 통하여 아래와 같은 몇 가지를 알 수 있다.<br/> ??우선 조선족의 뗏목소리는 두만강 계와 압록강 계 두 가지로 나눌 수 있으며 전자가 후자에 비해 수적으로 우세인 편이다. 이외에 송화강 계 떳목소리도 있었을 것 같으나 현재까지는 보고된 자료가 없다.<br/> ??다음으로 조선족의 뗏목소리는 뗏꾼들의 애환을 통해 살아남기 위해서는 이곳저곳 떠돌아다니면서 각가지 난관과 위험을 극복해야 했던 해방 전 조선족들의 고달픈 처지와 그 같은 어려움 속에서도 희망을 잃지 않고 꿋꿋이 삶을 헤쳐 나가려는 의지를 노래하고 있다. 이 점에서 볼 때 뗏꾼들의 희로애락은 결국은 조선족 민중들의 삶의 애환과 잇닿아진다.<br/> ??그리고 조선족의 뗏목소리는 그 형태에서 단절가, 분절가, 장가 등 여러 가지 양식을 취하고 있고 가창구조는 2가보 격과 4가보 격이 대부분이다. 음수률에서는 3ㆍ4조와 4ㆍ4조가 지배적이다.<br/> ??조선족의 뗏목소리는 조선족민요유산에서 독특한 자리를 차지하는 민속음악의 한 부분으로서 그것은 조선족 뗏꾼들의 생활의 노래이자 그 자신들의 노래이며 조선족뗏꾼들의 삶을 의미있게 하는 노래라 하겠다. ??We could say that TwnnenRiverandYaluRiveraretheancient and honorable for the Korean Nationality. Ever since the mid-19th century, more than one millions of compatriots have crossed the Tumnen River and Yalu River, came to Manchu area and found a new living front, two rivers are closely linked to the fate of the Korean nationality. The stories and songs about two rivers are so much that also be the trace of history and culture about the Korean Nationality.<br/> ??Tumen River and Yalu River Raft Song is a part of the Korean folk which lyrically expresses the joy, anger, sorrow, and pleasure of the Korean people. Meanwhile the research on the Tumen River and Yalu River Raft Song is very important to culturally understand the Korean people’s living Story associated with the Raft Song, and to grasp raft man’s reality awareness and life sentiment. The Korean Raft Song is decided into two systems, namely Tumen River system and Yalu River system, the formeris more superior in numbers than latter.<br/> ??In addition to this .it seems that Songhua River System RaftSong is presence, but it is no reported so far.<br/> ??The Korean Raft Song is praising the exhausted plight of the Korean people in the liberation, which is overcoming various difficult and dangerous for surviving by running a drift everywhere, through joys and sorrows of the Korean Raft Man. The Korean Raft Song also is praising the willpower of strongly surviving with not losing hope in so difficulty time. From this point, the joy, anger, sorrow, and pleasure of the Korean Raft man are connected with the whole Korean people’s joys and sorrows.<br/> ??The Korean Raft Song has many styles, for example, sort syllable song, dividing articulation song, long syllable song. The most of singing structure is 2 beat and 4 beat.<br/> ??The Korean Raft Song is a part of folk music, and has a special position in the Korean folk song heritage. The Korean Raft Song not be only the Korean raft man’s life song, but also be themselves song and be making the life to more meaningful song.

Ginsenoside Rh2 attenuates microglial activation against toxoplasmic encephalitis via TLR4/NF-kB signaling pathway

Xiang Xu,Lan Jin,Tong Jiang,Ying Lu,Fumie Aosai,Hu-Nan Piao,Guang-Hua Xu,Cheng-Hua Jin,Xue-Jun Jin,Juan Ma,Lian-Xun Piao 고려인삼학회 2020 Journal of Ginseng Research Vol.44 No.5

Background: Ginsenoside Rh2 (GRh2) is a characterized component in red ginseng widely used in Korea and China. GRh2 exhibits a wide range of pharmacological activities, such as anti-inflammatory, antioxidant, and anticancer properties. However, its effects on Toxoplasma gondii (T. gondii) infection have not been clarified yet. Methods: The effect of GRh2 against T. gondii was assessed under in vitro and in vivo experiments. The BV2 cells were infected with tachyzoites of T. gondii RH strain, and the effects of GRh2 were evaluated by MTT assay, morphological observations, immunofluorescence staining, a trypan blue exclusion assay, reverse transcription PCR, and Western blot analyses. The in vivo experiment was conducted with BALB/c mice inoculated with lethal amounts of tachyzoites with or without GRh2 treatment. Results and conclusion: The GRh2 treatment significantly inhibited the proliferation of T. gondii under in vitro and in vivo studies. Furthermore, GRh2 blocked the activation of microglia and specifically decreased the release of inflammatory mediators in response to T. gondii infection through TLR4/NF-kB signaling pathway. In mice, GRh2 conferred modest protection from a lethal dose of T. gondii. After the treatment, the proliferation of tachyzoites in the peritoneal cavity of infected mice markedly decreased. Moreover, GRh2 also significantly decreased the T. gondii burden in mouse brain tissues. These findings indicate that GRh2 exhibits an antieT. gondii effect and inhibits the microglial activation through TLR4/NF-kB signaling pathway, providing the basic pharmacological basis for the development of new drugs to treat toxoplasmic encephalitis.

Femtosecond Laser-Assisted Synthesis of ZnO Nanoparticles in Solvent with Visible Emission for Temperature Sensing

Huanhuan Xu,Lihe Yan,Jinhai Si,Yanmin Xu,Xun Hou 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.5

Zinc oxide (ZnO) nanoparticles (NPs) are synthesized by one-step femtosecond laser ablation of zinc powders in n-methyl pyrrolidone (NMP) at room temperature. The as-prepared ZnO NPs are fairly stable, water-soluble and have abundant surface functional groups resulting in a strong fluorescence in the visible region. By further annealing the ZnO NPs in the reacting solvent up to 120 ℃, the photoluminescence (PL) intensity of material can be significantly enhanced. Besides, the PL of ZnO NPs can change from blue to green by controlling the annealing temperature. The products exhibit excellent temperature sensing with high temperature sensitivity and a 1.3% change per ℃ response over a linear temperature sensing range (6–84 ℃) in aqueous buffer, which matches well with the physiologically relevant temperatures. Hence, the ZnO nanoparticle system can serve as a promising candidate for practical fluorescent temperatures nanosensors which can be used for accurate temperature monitoring within biological systems.

Ginsenoside Rh2 reduces depression in offspring of mice with maternal toxoplasma infection during pregnancy by inhibiting microglial activation via the HMGB1/TLR4/NF-kB signaling pathway

Xiang Xu,Yu-Nan Lu,Jia-Hui Cheng,Hui-Wen Lan,Jing-Mei Lu,Guang-Nan Jin,Guang-Hua Xu,Cheng-Hua Jin,Juan Ma,Hu-Nan Piao,Xuejun Jin,Lian-Xun Piao 고려인삼학회 2022 Journal of Ginseng Research Vol.46 No.1

Background: Maternal Toxoplasma gondii (T. gondii) infection during pregnancy has been associated with various mental illnesses in the offspring. Ginsenoside Rh2 (GRh2) is a major bioactive compound obtained from ginseng that has an anti-T. gondii effect and attenuates microglial activation through toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-kB) signaling pathway. GRh2 also alleviated tumor-associated or lipopolysaccharide-induced depression. However, the effects and potential mechanisms of GRh2 on depression-like behavior in mouse offspring caused by maternal T. gondii infection during pregnancy have not been investigated. Methods: We examined GRh2 effects on the depression-like behavior in mouse offspring, caused by maternal T. gondii infection during pregnancy, by measuring depression-like behaviors and assaying parameters at the neuronal and molecular level. Results: We showed that GRh2 significantly improved behavioral measures: sucrose consumption, forced swim time and tail suspended immobility time of their offspring. These corresponded with increased tissue concentrations of 5-hydroxytryptamine and dopamine, and attenuated indoleamine 2,3-dioxygenase or enhanced tyrosine hydroxylase expression in the prefrontal cortex. GRh2 ameliorated neuronal damage in the prefrontal cortex. Molecular docking results revealed that GRh2 binds strongly to both TLR4 and high mobility group box 1 (HMGB1). Conclusion: This study demonstrated that GRh2 ameliorated the depression-like behavior in mouse offspring of maternal T. gondii infection during pregnancy by attenuating the excessive activation of microglia and neuroinflammation through the HMGB1/TLR4/NF-kB signaling pathway. It suggests that GRh2 could be considered a potential therapy in preventing and treating psychiatric disorders in the offspring mice of mothers with prenatal exposure to T. gondii infection.

GROWTH AND FIXED POINTS OF MEROMORPHIC SOLUTIONS OF HIGHER-ORDER LINEAR DIFFERENTIAL EQUATIONS

Xu, Jun-Feng,Yi, Hong-Xun Korean Mathematical Society 2009 대한수학회지 Vol.46 No.4

In this paper, we investigate the growth and fixed points of meromorphic solutions of higher order linear differential equations with meromorphic coefficients and their derivatives. Because of the restriction of differential equations, we obtain that the properties of fixed points of meromorphic solutions of higher order linear differential equations with meromorphic coefficients and their derivatives are more interesting than that of general transcendental meromorphic functions. Our results extend the previous results due to M. Frei, M. Ozawa, G. Gundersen, and J. K. Langley and Z. Chen and K. Shon.

Finite Element Analysis and Optimization of Dither Mechanism in Dithered Ring Laser Gyroscope

Xu-dong Yu,Guo Wei,Xing-wu Long,Jian-xun Tang 한국정밀공학회 2013 International Journal of Precision Engineering and Vol. No.

This paper presents an optimal structural design of dither mechanism in dithered ring laser gyroscope (DRLG) using finite element analysis (FEA). We establish an approximate theoretical model of the dithering mechanism to calculate resonant frequency and adopt the modal analysis and dynamics analysis to search the optimal solution. The validity and efficiency of the FEA are conformed by comparing with the sinusoidal and random vibration experimental results. An optimal dither mechanism is fabricated and measured experimentally. The results demonstrate the good vibration-isolated performance for the optimal design.