Experimental study on shear performance of partially precast Castellated Steel Reinforced Concrete (CPSRC) beams

Yong Yang,Yunlong Yu,Yuxiang Guo,Charles W. Roeder,Yicong Xue,Yongjian Shao 국제구조공학회 2016 Steel and Composite Structures, An International J Vol.21 No.2

A new kind of partially precast or prefabricated castellated steel reinforced concrete beam, which is abbreviated here as CPSRC beam, was presented and introduced in this paper. This kind of CPSRC beam is composed of a precast outer-part and a cast-in-place inner-part. The precast outer-part is composed of an encased castellated steel shape, reinforcement bars and high performance concrete. The cast-in-place inner-part is made of common strength concrete, and is casted with the floor slabs simultaneously. In order to investigate the shear performance of the CPSRC beam, experiments of six CPSRC T-beam specimens, together with experiments of one cast-in-place SRC control T-beam specimen were conducted. All the specimens were subjected to sagging bending moment (or positive moment). In the tests, the influence of casting different strength of concrete in the cross section on the shear performance of the PPSRC beam was firstly emphasized, and the effect of the shear span-to-depth ratio on that were also especially taken into account too. During the tests, the shear force-deflection curves were recorded, while the strains of concrete, the steel shapes as well as the reinforcement stirrups at the shear zone of the specimens were also measured, and the crack propagation pattern together with the failure pattern was as well observed in detail. Based on the test results, the shear failure mechanism was clearly revealed, and the effect of the concrete strength and shear span-to-depth ratios were investigated. The shear capacity of such kind of CPSRC was furthermore discussed, and the influences of the holes on the steel shape on the shear performance were particularly analyzed.

An Improved Contention Access Mechanism for FPRP to Increase Throughput

Qi Yang,Yuxiang Zhuang,Jianghong Shi 한국전자통신연구원 2013 ETRI Journal Vol.35 No.1

Five-phase reservation protocol (FPRP) is a contentionbased media access control protocol for wireless ad hoc networks. FPRP uses a five-phase reservation process to establish slot assignments based on time division multiple access. It allows a node to reserve only one slot in an information frame. Once a node has reserved a slot, it will cease contending for other slots. As a result, there may be less contending nodes in the remaining slots, so the time slots in an information frame are not fully used by FPRP. To improve time slot utilization, this paper proposes an improved pseudo-Bayesian algorithm, based on which an improved contention access mechanism for FPRP is proposed, in which nodes are allowed to contend for more than one slot in a reservation frame according to a certain probability/priority. Simulation results indicate that the proposed mechanism performs better than FPRP in time slot utilization and hence the network throughput under various scenarios.

Hopf Bifurcation Study of Inductively Coupled Power Transfer Systems Based on SS-type Compensation

Xia, Chenyang,Yang, Ying,Peng, Yuxiang,Hu, Aiguo Patrick The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.3

In order to analyze the nonlinear phenomena of the bifurcation and chaos caused by the switching of nonlinear switching devices in inductively coupled power transfer (ICPT) systems, a Jacobian matrix model, based on discrete mapping numerical modeling, is established to judge the system stability of the periodic closed orbit and to study the nonlinear behavior of Hopf bifurcation in a system under full resonance. The general flow of the parameter design, based on the stability principle for ICPT systems, is proposed to avoid the chaos and bifurcation phenomena caused by unreasonable parameter selection. Firstly, based on the state equation of SS-type compensation, a three-dimensional bifurcation diagram with the coupling coefficient as the bifurcation parameter is established with a numerical simulation to observe the nonlinear phenomena in the system. Then Filippov's method based on a Jacobian matrix model is adopted to deduce the boundary of stable operation and to judge the type of the bifurcation in the system. Then the general flow of the parameter design based on the stability principle for ICPT systems is proposed through the above analysis to realize stable operation under the conditions of weak coupling. Finally, an experimental platform is built to confirm the correctness of the numerical simulation and modeling.

Hopf Bifurcation Study of Inductively Coupled Power Transfer Systems Based on SS-type Compensation

Chenyang Xia,Ying Yang,Yuxiang Peng,Aiguo Patrick Hu 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.3

In order to analyze the nonlinear phenomena of the bifurcation and chaos caused by the switching of nonlinear switching devices in inductively coupled power transfer (ICPT) systems, a Jacobian matrix model, based on discrete mapping numerical modeling, is established to judge the system stability of the periodic closed orbit and to study the nonlinear behavior of Hopf bifurcation in a system under full resonance. The general flow of the parameter design, based on the stability principle for ICPT systems, is proposed to avoid the chaos and bifurcation phenomena caused by unreasonable parameter selection. Firstly, based on the state equation of SS-type compensation, a three-dimensional bifurcation diagram with the coupling coefficient as the bifurcation parameter is established with a numerical simulation to observe the nonlinear phenomena in the system. Then Filippov’s method based on a Jacobian matrix model is adopted to deduce the boundary of stable operation and to judge the type of the bifurcation in the system. Then the general flow of the parameter design based on the stability principle for ICPT systems is proposed through the above analysis to realize stable operation under the conditions of weak coupling. Finally, an experimental platform is built to confirm the correctness of the numerical simulation and modeling.

Anthocyanin accumulation enhanced in Lc-transgenic cotton under light and increased resistance to bollworm

Xiaoping Fan,Bohong Fan,Yuxiang Wang,Weicai Yang 한국식물생명공학회 2016 Plant biotechnology reports Vol.10 No.1

Breeding of naturally colored cotton fiber has been hampered by the limited germplasm, an alternative way is to use transgenic approach to create more germplasm for breeding. Here, we report our effort to engineer anthocyanin production in cotton. The maize Lc gene, under the control of the constitutive 35S promoter, was introduced into cotton through genetic transformation. Our data showed that the expression of the Lc gene alone is sufficient to trigger the accumulation of anthocyanin in a variety of cell types including fiber cells in cotton. However, the accumulation of colored anthocyanin in cotton fibers requires the participation of light signaling. These data indicate that it is feasible to engineer colored fibers through transgenic approach in cotton. Furthermore, we showed that the Lc-transgenic cotton plants are resistant to cotton bollworm. These transgenic plants are, therefore, potentially useful for cotton breeding against cotton bollworm.

Modified exosomal SIRPα variants alleviate white matter injury after intracerebral hemorrhage via microglia/macrophages

Xinjie Gao,Heng Yang,Weiping Xiao,Jiabin Su,Yuwen Zhang,He Wang,Wei Ni,Yuxiang Gu 한국생체재료학회 2022 생체재료학회지 Vol.26 No.4

Background: Despite limited efficiency, modulation of microglia/macrophages has shown to attenuate neuroinflammation after intracerebral hemorrhage (ICH). In this context, we evaluated the efficacy of modified exosomal signal regulatory protein α (SIRPα) variants (SIRPα-v Exos) in microglia/macrophages and neuroinflammation-associated white matter injury after ICH. Methods: SIRPα-v Exos were engineered to block CD47-SIRPα interactions. After obtaining SIRPα-v Exos from lentivirus-infected mesenchymal stem cells, C57BL/6 mice suffering from ICH underwent consecutive intravenous injections of SIRPα-v Exos (6 mg/kg) for 14 days. Afterwards, the volume of hematoma and neurological dysfunctions were assessed in mice continuously until 35 days after ICH. In addition, demyelination, electrophysiology and neuroinflammation were evaluated. Furthermore, the mechanisms of microglial regulation by SIRPα-v Exos were investigated in vitro under coculture conditions. Results: The results demonstrated that the clearance of hematoma in mice suffering from ICH was accelerated after SIRPα-v Exo treatment. SIRPα-v Exos improved long-term neurological dysfunction by ameliorating white matter injury. In addition, SIRPα-v Exos recruited regulatory T cells (Tregs) to promote M2 polarization of microglia/macrophages in the peri-hematoma tissue. In vitro experiments further showed that SIRPα-v Exos regulated primary microglia in a direct and indirect manner in synergy with Tregs. Conclusion: Our studies revealed that SIRPα-v Exos could accelerate the clearance of hematoma and ameliorate secondary white matter injury after ICH through regulation of microglia/macrophages. SIRPα-v Exos may become a promising treatment for ICH in clinical practice.

Implications of Sarcopenia and Glucometabolism Parameters of Muscle Derived From Baseline and End-of-Treatment 18F-FDG PET/CT in Diffuse Large B-Cell Lymphoma

Tan Xiaoyue,Sun Xiaolin,Chen Yang,Wang Fanghu,Shang Yuxiang,Zhang Qing,Yuan Hui,Jiang Lei 대한영상의학회 2024 Korean Journal of Radiology Vol.25 No.3

Objective: We previously found that the incidence of sarcopenia increased with declining glucose metabolism of muscle in patients with treatment-naïve diffuse large B-cell lymphoma (DLBCL). This study aimed to investigate the relationship between sarcopenia and muscle glucometabolism using 18F-FDG PET/CT at baseline and end-of-treatment, analyze the changes in these parameters through treatment, and assess their prognostic values. Materials and Methods: The records of 103 patients with DLBCL (median 54 years [range, 21–76]; male:female, 50:53) were retrospectively reviewed. Skeletal muscle area at the third lumbar vertebral (L3) level was measured, and skeletal muscle index (SMI) was calculated to determine sarcopenia, defined as SMI < 44.77 cm2/m2 and < 32.50 cm2/m2 for male and female, respectively. Glucometabolic parameters of the psoas major muscle, including maximum standardized uptake value (SUVmax) and mean standardized uptake value (SUVmean), were measured at L3 as well. Their changes across treatment were also calculated as ΔSMI, ΔSUVmax, and ΔSUVmean; Δbody mass index was also calculated. Associations between SMI and the metabolic parameters were analyzed, and their associations with progression-free survival (PFS) and overall survival (OS) were identified. Results: The incidence of sarcopenia was 29.1% and 36.9% before and after treatment, respectively. SMI (P = 0.004) was lower, and sarcopenia was more frequent (P = 0.011) at end-of-treatment than at baseline. The SUVmax and SUVmean of muscle were lower (P < 0.001) in sarcopenia than in non-sarcopenia at both baseline and end-of-treatment. ΔSMI was positively correlated with ΔSUVmax of muscle (P = 0.022). Multivariable Cox regression analysis showed that sarcopenia at end-of-treatment was independently negatively associated with PFS (adjusted hazard ratio [95% confidence interval], 2.469 [1.022–5.965]), while sarcopenia at baseline was independently negatively associated with OS (5.051 [1.453–17.562]). Conclusion: Sarcopenic patients had lower muscle glucometabolism, and the muscular and metabolic changes across treatment were positively correlated. Sarcopenia at baseline and end-of-treatment was negatively associated with the prognosis of DLBCL.

A Novel Identification Approach for Palm Bio-impedance Spectroscopy

Lintao Lv,Sheng Wang,Shiqi Huang,Xinhong Hei,Yuxiang Yang 대한전기학회 2019 Journal of Electrical Engineering & Technology Vol.14 No.5

Aiming at the properties of the palm bio-impedance spectroscopy (PBIS) data and shortage of the existing algorithms, this paper proposed a kind of the PBIS identification method based on immune clone. This method mainly consisted of three parts, which are data normalization, feature selection and matching. The PBIS algorithm constructed a new classifier based on the immune clone selection algorithm (ICSA) and the hidden space support vector machine (HSSVM), called the ICSA-HSSVM. It was compared with other classifiers such as Euclidean distance, cosine distance and support vector machine (SVM). The experimental results show that the proposed classification method can achieve more than 95% accuracy in identity recognition. The PBIS biometric identification tech depends on the human body inherent characteristics to carry out the status identification so as to overcome the drawbacks of traditional information safety tech status identification. The main advantages of PBIS algorithm include four aspects. The first is the uniqueness, universality, stability, easy collection, and it is basically not being subject to the influence of pathological changes in the human body positions. The second is not sensitive to the environment and the excellent recognition performance can be obtained through the method easily. The three is high stability and uniqueness when it is served as the biometric potentiality, being in agreement with biometric identification requirements. (4) The four is able to resist against counterfeiting attacks effectively. The method proposed in this paper is of great theoretical and practical values in the fields of national public security, internet information security, military communication security, micro-blog micro-message public opinion supervision.

클러스터링 알고리즘 기반의 임베딩 기법 성능 비교 및 분석

박정민(Jungmin Park),박희민(Heemin Park),양선아(Seona Yang),순위샹(Yuxiang Sun),이용주(Yongju Lee) 한국방송·미디어공학회 2021 한국방송공학회 학술발표대회 논문집 Vol.2021 No.11

최근 구글, 아마존, LOD 등을 중심으로 지식 그래프(Knowledge graph)와 같은 검색 고도화 연구가 활발히 수행되고 있다.그러나 대규모 지식 그래프 인덱싱 시스템에서 데이터가 어떻게 임베딩(embedding)되고, 딥러닝(deep learning) 되는지는 상대적으로 거의 연구가 되지 않고 있다. 이에 본 논문에서는 임베딩 모델에 대한 성능평가를 통해 데이터셋에 대해 어떤 모델이 가장 좋은 지식 임베딩 방법을 도출하는지 분석한다.

PREPARATION, CHARACTERIZATION AND MAGNETIC PROPERTIES OF NANO-Fe3O4 AND COBALT-DOPED NANO-Fe3O4 BY CO-PRECIPITATION METHOD

XIAOJUAN LIANG,WEIWEI HUAN,XIANGCHEN JIA,HAIJUN DING,YUXIANG YANG,XIANGNONG LIU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2010 NANO Vol.5 No.4

Pure nano-Fe3O4 and cobalt-doped nano-Fe3O4 particles are successfully synthesized by co-precipitation method using tetramethylammonium hydroxide (TMAOH) as alkali. Several key factors that may affect preparation are carefully discussed such as alkali concentration, alkali dosage, reaction temperature, iron salt solution concentration and dispersant agents. Such nano-Fe3O4 particles prepared have good dispersibility and a very narrow size distribution with the average diameter about 38 nm, which are proved to be cubic spinel Fe3O4 crystal by XRD pattern. It is also found that the addition of PEG-4000 surfactant can improve the dispersibility of nanoparticles. In our work, effects of cobalt dopant concentration on magnetic properties of cobalt-doped nano-Fe3O4 are also discussed. The result shows that the coercivity of cobalt-doped nanoparticles changes greatly with the variation of cobalt dopant concentration. The maximum coercivity reaches as high as 1628 Oe, which is very meaningful for preparation of materials with high coercivity.