An Improved DMRS Design Scheme of LTE-Advanced Uplink

Xiaowen Li,Youbo Feng,Dan Wang 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.4

The 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) uplink supports only a single antenna transmission. However, in order to improve the uplink spectrum efficiency, support multiple antenna transmission in LTE-Advanced. Meanwhile, taking into account backwards compatibility for LTE. LTE-Advanced De-Modulation Reference Signal (DMRS) needs to be designed [1]. According to requirement of LTE-Advanced uplink pilot design, introducing orthogonal cover code (OCC) as a supplement, analysis and study of the current problems, proposes a Circular Shift (CS), Group/Sequence Hopping (GSH) and the OCC joint instructions method of pilot design. Finally, simulation and analysis of the performance of this scheme. Results show that this scheme can meet LTE- Advanced demand for pilot design well.

A novel PEO ceramic insulating wire for marine dry-type power transformer

Haomin Li,Meng Zhang,Qirui Zhang,Xiaowen Wu,Li Lei,Yingsan Geng 한국표면공학회 2023 한국표면공학회 학술발표회 초록집 Vol.2023 No.11-1

The visible and ultraviolet organic light-emitting diodes with germanium dioxide as facile solution-processed anode buffer layer

Kai Xu,Zhenchang Tang,Yan Zhang,Wanshu Li,Haiou Li,Lihui Wang,Li-Ming Liu,Hong-Hang Wang,Feng Chi,Xiaowen Zhang 한국물리학회 2019 Current Applied Physics Vol.19 No.10

Germanium dioxide (GeO2) aqueous solutions are facilely prepared and the corresponding anode buffer layers (ABLs) with solution process are demonstrated. Atomic force microscopy, X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy measurements show that solution-processed GeO2 behaves superior film morphology and enhanced work function. Using GeO2 as ABL of organic light-emitting diodes (OLEDs), the visible device with tris(8-hydroxy-quinolinato)aluminium as emitter gives maximum luminous efficiency of 6.5 cd/A and power efficiency of 3.5 lm/W, the ultraviolet device with 3-(4-biphenyl)-4-phenyl-5-tert-butylphenyl- 1,2,4-triazole as emitter exhibits short-wavelength emission with peak of 376 nm, full-width at halfmaximum of 42 nm, maximum radiance of 3.36 mW/cm2 and external quantum efficiency of 1.5%. The performances are almost comparable to the counterparts with poly (3,4-ethylenedioxythiophene):poly (styrenesulfonate) as ABL. The current, impedance, phase and capacitance as a function of voltage characteristics elucidate that the GeO2 ABL formed from appropriate concentration of GeO2 aqueous solution favors hole injection enhancement and accordingly promoting device performance.

Numerical simulation of a regenerative thermal oxidizer for volatile organic compounds treatment

Xiaowen Hao,Ruixin Li,Jiao Wang,Xinfei Yang 대한환경공학회 2018 Environmental Engineering Research Vol.23 No.4

As regulations governing the control of volatile organic compounds (VOCs) have become increasingly stringent in China, regenerative thermal oxidizers (RTOs) have been more frequently applied in medium- and high-concentration VOCs treatments. However, due to the lack of existing RTO-related research, experience remains a dominant factor for industrial application. This paper thus aimed to establish a model for industrial RTOs, using a transient simulation method and thermal equilibrium model to simulate the internal velocities and temperature distributions of an RTO across multiple cycles. A comparison showed an error of less than 5% between most correlating simulated and experimental measurement points, verifying that the simulation method was accurate. After verification, the velocity and temperature fields inside the RTO were simulated to study the uniformity of temperature and velocity within the packed beds: both fields displayed high uniformity after gas flowed through the honeycomb regenerator. The effects of air volume, VOCs concentrations, and valve switching times on the oxidation chamber temperature, RTO outlet temperature, and thermal efficiency (as well as their averages) were studied. The VOCs removal rate in this study was constantly above 98%, and the average thermal efficiency reached 90%.

Wavelength Converter Placement under the Fixed-Alternate Routing Algorithm in Wavelength-Routed All-Optical Networks

Xiaowen Chu,Bo Li 한국정보과학회 2002 한국정보과학회 학술발표논문집 Vol.2002 No.1

The synergistic benefits of β-aminobutyric acid and γ-aminobutyrate on salt and drought tolerance in cassava

Ma Xiaowen,Gu Jinbao,Luo Qingwen,Wen Mingfu,Li Hua,Wang Zhen-Yu 한국식물생명공학회 2022 Plant biotechnology reports Vol.16 No.1

β-Aminobutyric acid (BABA) and γ-aminobutyrate (GABA) had a positive role in alleviating the damage when plants were exposed to abiotic and biotic stresses. However, it is not known whether exogenous of GABA and BABA could improve the tolerance of cassava plants, and their synergistic benefits. In the current study, we found that the cassava seedling improved the tolerance by exogenous of BABA and GABA under salt and drought stress condition, as reflected by reducing the accu- mulation of hydrogen peroxide and increasing the activities of antioxidant enzymes. Meanwhile, the expression of genes encoding antioxidant enzymes was significantly unregulated by salt or drought stress after application of BABA and GABA, separately. Moreover, the transcript levels of DREB2A and SOS2 were significantly unregulated by salt after application of BABA and GABA, separately, and expression of DREB2A, NCED3, and CBF3 was significantly unregulated by drought stress after application of BABA and GABA, separately. Interestingly, there was a synergistic benefit on improving the plant stress tolerance by combining the application of BABA and GABA. Therefore, our study provides new insights into maintaining the high yield by combining use of the chemical compounds in cassava which is relatively hard to be genetically modified.

Structure and biocompatibility of highly oriented poly(lactic acid) film produced by biaxial solid hot stretching

Zhengqiu Li,Lin Ye,Xiaowen Zhao,Phil Coates,Fin Caton-Rose,Michael Martyn 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.52 No.-

Highly oriented long-chain-branched poly(lactic acid) (LCB-PLA)film was fabricated through biaxial hotstretching in solid state. Compared with neat PLA, more homogeneousfilm with higher draw ratio can beobtained for LCB-PLA. With increasing draw ratio, the long period, lamellae thickness and grain size ofLCB-PLA decreased, while the crystallinity increased. For LCB-PLA with draw ratio of 6*6, the tensilestrength and elongation at break can reach up to 208 6 MPa and 85% respectively. After drawing, theincreasing content ofCH3 and C¼O group on the surface of LCB-PLAfilm was beneficial for celladhesion and growth on it.

Solution-processed WOx hole injection layer for efficient fluorescent blue organic light-emitting diode

Wanshu Li,Yan Zhang,Qinghong Zheng,Kai Xu,Xiuyun Zhang,Liming Liu,Bin Wei,Lihui Wang,Jiwen Xu,Xiaowen Zhang 한국물리학회 2018 Current Applied Physics Vol.18 No.5

Solution-processed tungsten oxide (s-WOx) interfacial layer for efficient hole injection in fluorescent blue organic light-emitting diode (OLED) is demonstrated. The OLED using 2-methyl-9,10-bis(naphthalen-2- yl)anthracene (MADN) as emitter shows luminous efficiency of 3.3 cd/A, power efficiency of 2.5 lm/W and external quantum efficiency of 4.6% with Commission Internationale d'Eclairage (CIE) color coordinates of (0.154, 0.102). Using MADN doped 1-4-di-[4-(N,N-diphenyl)amino]styryl-benzene as emitter, luminous efficiency of 10.8 cd/A, power efficiency of 6.4 lm/W and external quantum efficiency of 7.2% with CIE color coordinates of (0.167, 0.283) are achieved. Atomic force microscopy and X-ray photoelectron spectroscopy show that s-WOx features superior film morphology and non-stoichiometry with slight oxygen deficiency. Current-voltage characteristics and impedance spectroscopy analysis indicate that s-WOx behaves slightly enhanced hole injection and accordingly contributes to improved device performance in comparison with conventional vacuum thermal evaporation WOx. Our results pave an alternative way for broadeningWOx application with solution process and advancing fluorescent blue OLEDs.

Integrated fault location method for distribution networks based on IACO‑PS

Shuqing Zhang,Xiaowen Zhang,Anqi Jiang,Liguo Zhang,Mingliang Li 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.1

This paper develops a new hybrid method based on an improved ant colony optimization algorithm that incorporates pattern search (IACO-PS) for determining the location of faults in a distribution network. The performance of the conventional ant colony optimization (ACO) algorithm is improved using the opposite-based learning strategy to generate the initial population and adding a weight coefficient into the pheromone update mechanism to dynamically adjust the pheromone volatilization factor. The hybrid IACO-PS algorithm combines the individual strengths of ACO and PS. In addition, the fitness function is constructed by counting the false and missing fault information into the fault variable. In optimizing benchmark function experiments, the proposed hybrid IACO-PS presents a superior performance when compared to other improved versions of ACO. The effectiveness of the proposed approach is corroborated by tests performed on an IEEE 134-bus network. Simulation results show that the proposed hybrid IACO-PS method can determine the location of a fault even in the presence of fault distortion. In addition, it is immune to noise and data loss errors. Finally, the method proposed in this paper significantly outperforms other published fault location methods, and it can accurately locate faults and identify the type of distortion.

Mass transfer and kinetics study on the sulfite forced oxidation with manganese ion catalyst

Zhao Bo,Li Yan,Zhuo Yuqun,Tong Huiling,Zhang Xiaowen,Chen Changhe 한국화학공학회 2007 Korean Journal of Chemical Engineering Vol.24 No.3

limestone scrubbing is the most common flue gas desulfurization process (FGD) for control of sulfurdioxide emissions from the combustion of fossil fuels. Forced oxidation, which controls the overall reaction of the sulfurdioxide absorption, is the key path of the process. Manganese which comes from the coal is one of the catalysts duringthe forced oxidation process. In the present work, the two-film theory was used to analyze the sulfite forced oxidationreaction with an image boundary recognition technique, and the oxidation rate was experimentally studied by contactingpure oxygen with a sodium sulfite solution. There was a critical sulfite concentration 0.328 mol/Lwithout catalyst ortion constant k; furthermore, we obtained the order with respect to the sulfite and Mn2+ concentrations. When the Mn2+catalyst concentration was kept unchanged, the sulfite oxidation reaction rate was controlled by dual film and the reac-tion kinetics was first order with respect to sulfite while concentration was below 0.328 mol/L; the sulfite oxidationreaction rate was controlled by gas film only and the reaction kinetics was zero order with respect to sulfite while concentration over 0.328 mol/L. When concentration was kept unchanged, the sulfite oxidation reaction rate de-pended on gas-liquid mass transfer and the reaction kinetics was diferent in various stages with respect to Mn2+ con-centrations.