Interference Alignment Based Transceiver Design in OSG mode of HetNets

( Qin Niu ),( Zhimin Zeng ),( Tiankui Zhang ),( Zhirui Hu ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.6

This paper focuses on solving co-channel interference (CCI) issues arising in the open subscriber group (OSG) mode of heterogeneous networks (HetNets). Considering a general framework consisting of arbitrary number of picocells within a macro cell, where the inter-user interference (IUI) is the main CCI to macro user equipments (UEs), while the the inter-cell interference (ICI) is the major CCI to pico UEs. In this paper, three IA based transceiver design schemes are proposed. For macro cell, we uniformly use block diagonalization (BD) scheme to eliminate the IUI. And for picocells, three IA schemes are proposed to mitigate the ICI. The first scheme, named as zero forcing IA (ZF-IA) scheme, aligns the inter picocell interference onto an arbitrary sub-space of the cross-tier interference using ZF scheme. Considering the channel state information (CSI) of the desired channel of pico UEs, the second scheme, named as optimal desired sub-channel selected IA (ODC-IA) scheme, aligns the inter picocell interference onto a certain sub-space of the cross-tier interference, which guarantees the largest channel gain of the desired signal of pico UEs. The third IA scheme, named as maximum cross-tier interference selected IA (MI-IA) scheme, is designed for the system with less receive antennas. The inter picocell interference is aligned onto the space of the strongest cross-tier interference and only the interference on this space is nullified. The complexity analysis and simulations show that the proposed transceiver design schemes outperform the existing IA schemes in the OSG mode of HetNets, and the MI-IA scheme reduces the requirement of the receive antennas number with lower complexity.

MiR-338-3p Enhances Ovarian Cancer Cell Sensitivity to Cisplatin by Downregulating WNT2B

Qin Niu,Zhenghong Liu,Jia Gao,Qiao Wang 연세대학교의과대학 2019 Yonsei medical journal Vol.60 No.12

Purpose: Chemoresistance is a concern in ovarian cancer patients, in whom survival remains. MicroRNA, a novel class of smallRNAs, have frequently been found to be dysregulated in human malignancies and to act as negative regulators of gene expression. This study aimed to explore the function of miR-338-3p in cisplatin resistance in ovarian cancer and potential molecular mechanismsthereof. Materials and Methods: The expression levels of miR-338-3p and WNT2B in ovarian cancer tissues and cells were estimated byreal-time quantitative polymerase chain reaction (RT-qPCR). In addition, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazol-3-ium bromide (MTT), transwell, and flow cytometry assays were used to assess biological role of miR-338-3p in vitro. Western blotassay was conducted to measure protein expression of WNT2B, epithelial-mesenchymal transition (EMT)-related proteins, andapoptosis-related proteins. The relationship between miR-338-3p and WNT2B was confirmed by dual-luciferase reporter. Finally, axenograft tumor model was developed to explore the effects of overexpression of miR-338-3p on tumor growth in ovarian cancerin vivo. Results: MiR-338-3p was downregulated in cisplatin resistant ovarian cancer tissues and cells. Mechanistically, high expression ofmiR-338-3p enhanced cell sensitivity to cisplatin by inhibiting proliferation, motility, and EMT and by promoting apoptosis via targetingWNT2B expression in vitro. Furthermore, overexpression of miR-338-3p increased cisplatin sensitivity among ovarian cancerin an in vivo xenograft tumor model. Conclusion: MiR-338-3p enhances the sensitivity of ovarian cancer cells to cisplatin by downregulating WNT2B.

Glucosamine induces cell death via proteasome inhibition in human ALVA41 prostate cancer cell

Bao-Qin Liu,Hua-Qin Wang,Xin Meng,Chao Li,Yan-Yan Gao,Ning Li,Xiao-Fang Niu,Yifu Guan 생화학분자생물학회 2011 Experimental and molecular medicine Vol.43 No.9

Glucosamine, a naturally occurring amino monosaccharide,has been reported to play a role in the regulation of apoptosis more than half century. However the effect of glucosamine on tumor cells and the involved molecular mechanisms have not been thoroughly investigated. Glucosamine enters the hexosamine biosynthetic pathway (HBP) downstream of the rate-limiting step catalyzed by the GFAT (glutamine:fluctose-6-phosphate amidotransferase), providing UDPGlcNAc substrates for O-linked β-N-acetylglucosamine (O-GlcNAc) protein modification. Considering that O-GlcNAc modification of proteasome subunits inhibits its activity, we examined whether glucosamine induces growth inhibition via affecting proteasomal activity. In the present study, we found glucosamine inhibited proteasomal activity and the proliferation of ALVA41 prostate cancer cells. The inhibition of proteasomal activity results in the accumulation of ubiquitinated proteins, followed by induction of apoptosis. In addition, we demonstrated that glucosamine downregulated proteasome activator PA28γ and overexpression of PA28γ rescued the proteasomal activity and growth inhibition mediated by glucosamine. We further demonstrated that inhibition of O-GlcNAc abrogated PA28γ suppression induced by glucosamine. These findings suggest that glucosamine may inhibit growth of ALVA41 cancer cells through downregulation of PA28γ and inhibition of proteasomal activity via O-GlcNAc modification.

Glucosamine induces cell death $via$ proteasome inhibition in human ALVA41 prostate cancer cell

Liu, Bao-Qin,Meng, Xin,Li, Chao,Gao, Yan-Yan,Li, Ning,Niu, Xiao-Fang,Guan, Yifu,Wang, Hua-Qin Korean Society for Biochemistry and Molecular Bion 2011 Experimental and molecular medicine Vol.43 No.9

Glucosamine, a naturally occurring amino monosaccharide, has been reported to play a role in the regulation of apoptosis more than half century. However the effect of glucosamine on tumor cells and the involved molecular mechanisms have not been thoroughly investigated. Glucosamine enters the hexosamine biosynthetic pathway (HBP) downstream of the rate-limiting step catalyzed by the GFAT (glutamine:fluctose- 6-phosphate amidotransferase), providing UDP-GlcNAc substrates for O-linked ${\beta}$-N-acetylglucosamine (O-GlcNAc) protein modification. Considering that O-GlcNAc modification of proteasome subunits inhibits its activity, we examined whether glucosamine induces growth inhibition $via$ affecting proteasomal activity. In the present study, we found glucosamine inhibited proteasomal activity and the proliferation of ALVA41 prostate cancer cells. The inhibition of proteasomal activity results in the accumulation of ubiquitinated proteins, followed by induction of apoptosis. In addition, we demonstrated that glucosamine downregulated proteasome activator $PA28{\gamma}$ and overexpression of $PA28{\gamma}$ rescued the proteasomal activity and growth inhibition mediated by glucosamine. We further demonstrated that inhibition of O-GlcNAc abrogated $PA28{\gamma}$ suppression induced by glucosamine. These findings suggest that glucosamine may inhibit growth of ALVA41 cancer cells through downregulation of $PA28{\gamma}$ and inhibition of proteasomal activity via O-GlcNAc modification.

Grain Morphology and Orientation Effect on the High‑Temperature Tensile Behavior of Directionally Solidified Magnesium Alloy

Qin Tang,Xiaoping Lin,Shengshi Zhao,Yi Niu,Heng Sun,Yun Dong 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.4

Columnar-structured Mg97.27Zn2.54Y0.19alloy with the preferred growth direction of ⟨22̄45⟩ and ⟨12̄33⟩, andMg98.01Zn1.84Y0.13Zr0.03alloy with the preferred growth direction of ⟨11̄20⟩ were prepared using the directional solidificationtechnique and then tensile tested at 250–300 °C. The results showed that the Mg97.27Zn2.54Y0.19alloy with columnar dendriticstructure experienced a significant deformation strengthening period when stretched at 250 °C, and a typical dynamicrecrystallization stage at 300 °C, which were mainly accounted for its well-developed secondary dendrites, a large numberof branch-shaped second phases distributed in the longitudinal grain boundary, and less granular second phases existingin the crystal. While in the whole test temperature range (250–300 °C), the stress–strain curves of Mg98.01Zn1.84Y0.13Zr0.03alloys with cellular dendritic crystals showed a steady deformation state because of the second phases with strip distributingin the longitudinal grain boundary, which was induced by a balance between the deformation strengthening and the dynamicrecrystallization. Especially at 300 °C, this steady deformation state existed in the strain of 5.6%–36%. The good uniformplastic deformation was closely related to the small misorientations between columnar grains, the associated movement ofgrains by grain boundary slipping, and the less percentage of dynamically recrystallized grains which could do harm to theorientation continuity of the columnar crystals.

Effects of the Charge Ions Strength on the Swelling of Organic–Inorganic Nanogels

Qin Yu,Xiangguo Lu,Jing Wang,Qi Guo,Liwei Niu 대한화학회 2016 Bulletin of the Korean Chemical Society Vol.37 No.7

The swelling behavior and swelling mechanism of hydrogels can be greatly affected by the charge strength of ions in them. To investigate such effects, we prepared two gels: a carboxylic acid gel (CAG) and a poly(2-acrylamide–methyl propane sulfonic acid) gel (SAG) based on starchy polyacrylamide (PAM) nanocomposite gels, both with montmorillonite, which underwent in situ intercalation, and used them as probes in swelling experiments. The equilibrium swelling rates (ESRs) of the hydrogels in both salt water and acidic water strongly depended on the charge strength of the ions in the chains. SAG had a higher ESR than CAG at the same mole ratio of polymer/water, which is attributed to the greater electrostatic repulsion between the strong electrolyte ions of SAG. Both water salinity and hydrogen ion contact of the hydrogels weakened ESR with the enhancement of charge ionic strength. The downward trend of ESR with increasing concentration of salt or hydrogen ions became weaker in SAG compared to CAG, which is attributed to the shielding and deprotonation effects of the strong electrolyte ions. Regarding the swelling mechanism, the chain relaxation occurred in neutral and acidic solutions for SAG and in neutral and weak acidic solutions for CAG, but water diffusion dominated in strong acidic solutions for CAG, leading to different swelling behaviors.

Physical Characteristics of Lighting Environment and Physiological Change of Drivers in Tunnel

Can Qin,Bo Liang,Jinghang Xiao,Jia’an Niu,Shiyong He 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.5

The physical characteristics (i.e., road surface luminance, sidewall luminance, overall uniformity of luminance, and longitudinal uniformity of luminance) of the tunnel and the physiological change (i.e., pupil diameter and heart rate) of the drivers were investigated by the real vehicle tests and the whole scale model. Experiments were carried out in the real tunnel and the whole scale model with the sidewalls covered by the energy-storage and self-luminous material coating (ESMC) and the fireproof material coating (FMC). The results also show that compared to FMC, the luminance and the luminance uniformity were higher, and the pupil diameter and heart rate of drivers were smaller for ESMC. Furthermore, the physical characteristics of the light environment are negatively correlated with the physiological change of drivers. Moreover, each decrease of 1 cd/mm2 in road surface luminance and sidewall luminance, the pupil diameter increase by 0.54 and 1.06 mm, the heart rate increase 7.29 and 14.15 times/min, respectively. Each decrease of 0.1 in luminance uniformity, the pupil diameter increase by 0.33 mm, the mean heart rate increase 4.41 times/min, respectively.

Application of Optimized GM (1, 1) Prediction Model based on Ant Colony Algorithm in the Medium and Long Term Load Forecasting

JunSong Qin,Yan Lu,Dongxiao Niu,Guodong Zhu 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.8

The medium and long term load forecasting is the basis of power planning, investment, production, scheduling and trade, which plays an important role in electric power safety and economic operation. In China, it has the increasing uncertainty and the uncertainty of random variation to forecast the medium and long term load. Thus we can regard it as a typical grey system. However, the traditional grey prediction method cannot be adapt to the needs of the load forecasting gradually. It need to be rich and perfect with the continuous improvement of power system complexity and power marketization degree. This paper studied the modelling mechanism of grey prediction model. Then we analyzed the problems existing in the model, including the boundary value problem, the background value structure problem and the least squares parameter identification problem. This paper put forward an optimization method to directly identify the boundary value x(0)(1), the developing coefficient a and grey coefficient b using ant colony algorithm according to the time response expression of GM(1,1) model, so that it established an optimized GM(1,1) prediction model based on ant colony algorithm. This model can fix the impact of boundary value, and also avoid the errors brought by the background value construction and the least squares parameter estimation. It can verify the effectiveness of the proposed optimization model through the load data simulation. And it can improve the prediction accuracy effectively.

Wavelet based system identification for a nonlinear experimental model

Li, Luyu,Qin, Han,Niu, Yun Techno-Press 2017 Smart Structures and Systems, An International Jou Vol.20 No.4

Traditional experimental verification for nonlinear system identification often faces the problem of experiment model repeatability. In our research, a steel frame experimental model is developed to imitate the behavior of a single story steel frame under horizontal excitation. Two adjustable rotational dampers are used to simulate the plastic hinge effect of the damaged beam-column joint. This model is suggested as a benchmark model for nonlinear dynamics study. Since the nonlinear form provided by the damper is unknown, a Morlet wavelet based method is introduced to identify the mathematical model of this structure under different damping cases. After the model identification, earthquake excitation tests are carried out to verify the generality of the identified model. The results show the extensive applicability and effectiveness of the identification method.

HARDY INEQUALITIES IN HALF SPACES OF THE HEISENBERG GROUP

Han, JunQiang,Niu, Pengcheng,Qin, Wenji Korean Mathematical Society 2008 대한수학회보 Vol.45 No.3

In this paper we prove some Hardy inequalities in the half space of the Heisenberg group and indicate the sharp constant.