Phase Noise Self-Cancellation Scheme Based on Orthogonal Polarization for OFDM System

( Yao Nie ),( Chunyan Feng ),( Fangfang Liu ),( Caili Guo ),( Wen Zhao ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.9

In orthogonal frequency-division multiplexing (OFDM) systems, phase noise introduced by the local oscillators can cause bit error rate (BER) performance degradation. To solve the phase noise problem, a novel orthogonal-polarization-based phase noise self-cancellation (OP-PNSC) scheme is proposed. First, the efficiency of canceling the phase noise of the OP-PNSC scheme in the AWGN channel is investigated. Then, the OP-PNSC scheme in the polarization-dependent loss (PDL) channel is investigated due to power imbalance caused by PDL, and a PDL pre-compensated OP-PNSC (PPC -OP-PNSC) scheme is proposed to mitigate the power imbalance caused by PDL. In addition, the performance of the PPC-OP-PNSC scheme is investigated, where the signal-to-interference-plus-noise ratio (SINR) and spectral efficiency (SE) performances are analyzed. Finally, a comparison between the OP-PNSC and polarization diversity scheme is discussed. The numerical results show that the BER and SINR performances of the OP-PNSC scheme outperform the case with the phase noise compensation and phase noise self-cancellation scheme.

A New Strategy to Improve the Efficiency and Sustainability of Candida parapsilosis Catalyzing Deracemization of (R,S)-1-Phenyl-1,2-Ethanediol Under Non-Growing Conditions: Increase of NADPH Availability

( Yao Nie ),( Yan Xu ),( Qing Sen Hu ),( Rong Xiao ) 한국미생물 · 생명공학회 2009 Journal of microbiology and biotechnology Vol.19 No.1

Microbial oxidoreductive systems have been widely used in asymmetric syntheses of optically active alcohols. However, when reused in multi-batch reaction, the catalytic efficiency and sustainability of non-growing cells usually decreased because of continuous consumption of required cofactors during the reaction process. A novel method for NADPH regeneration in cells was proposed by using pentose metabolism in microorganisms. Addition of D-xylose, L-arabinose, or D-ribose to the reaction significantly improved the conversion efficiency of deracemization of racemic 1-phenyl-1,2-ethanediol to (S)-isomer by Candida parapsilosis cells already used once, which afforded the product with high optical purity over 97%e.e. in high yield over 85% under an increased substrate concentration of 15 g/l. Compared with reactions without xylose, xylose added to multi-batch reactions had no influence on the activity of the enzyme catalyzing the key step in deracemization, but performed a promoting effect on the recovery of the metabolic activity of the non-growing cells with its consumption in each batch. The detection of activities of xylose reductase and xylitol dehydrogenase from cell-free extract of C. parapsilosis made xylose metabolism feasible in cells, and the depression of the pentose phosphate pathway inhibitor to this reaction further indicated that xylose facilitated the NADPH-required deracemization through the pentose phosphate pathway in C. parapsilosis. moreover, by investigating the cofactor pool, the xylose addition in reaction batches giving more NADPH, compared with those without xylose, suggested that the higher catalytic efficiency and sustainability of C. parapsilosis non-growing cells had resulted from xylose metabolism recycling NADPH for the deracemization.

Mixed Reinforcement Learning for Efficient Policy Optimization in Stochastic Environments

Yao Mu,Baiyu Peng,Ziqing Gu,Shengbo Eben Li,Chang Liu,Bingbing Nie,Jianfeng Zheng,Bo Zhang 제어로봇시스템학회 2020 제어로봇시스템학회 국제학술대회 논문집 Vol.2020 No.10

Reinforcement learning has the potential to control stochastic nonlinear systems in optimal manners successfully. We propose a mixed reinforcement learning (mixed RL) algorithm by simultaneously using dual representations of environmental dynamics to search the optimal policy. The dual representation includes an empirical dynamic model and a set of state-action data. The former can embed the designer’s knowledge and reduce the difficulty of learning, and the latter can be used to compensate the model inaccuracy since it reflects the real system dynamics accurately. Such a design has the capability of improving both learning accuracy and training speed. In the mixed RL framework, the additive uncertainty of stochastic model is compensated by using explored state-action data via iterative Bayesian estimator (IBE). The optimal policy is then computed in an iterative way by alternating between policy evaluation (PEV) and policy improvement (PIM). The effectiveness of mixed RL is demonstrated by a typical optimal control problem of stochastic non-affine nonlinear systems (i.e., double lane change task with an automated vehicle).

Research on the Implementation of Image Degradation and Restoration by using Model-Based Design Methodology

Yuge Yao,Yandong Yu,Yang Nie 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.9

The degradation and restoration of image are very important and widely studied in the field of computer visualization and image processing. The key of image restoration is to analyze the cause of image degradation, and to establish a reasonable model. The cause of image degradation is described by reasonable degradation model and specific parameters. In this paper, the linear image degradation model and common image restoration methods are described, and the system of image degradation model and image restoration is built. The simulation results show that the system of image degradation and restoration using Model-Based Design (MBD) methodology is not only efficient and simple, and convenient for hardware implementation.

A New Rapid Spectrophotometric Quantitative Determination Method for γ-Decalactone and Application in High-throughput Screening for γ-Decalactone Producing Strains

Yuping Zhao,Xiaoqing Mu,Yao Nie,Yan Xu 한국식품과학회 2014 Food Science and Biotechnology Vol.23 No.6

A new, rapid spectrophotometric quantitativedetermination method for γ-decalactone (GDL) was developedbased on the ferric hydroxamate reaction. Samples addedto a mixture of NH2OH·HCl and NaOH were heated toreact. Then HCl was added. Ferric chloride was added forcoloration, and 75% (v/v) ethanol was added. Absorbancevalues were measured after coloring for 10 min. Theconcentration range of a GDL calibration curve was 0.125-8.14 g/L. A 96-well plate high-throughput screening methodwas established to obtain desirable strains. A total of 215GDL-producing strains were identified from 4,327 samples. The highest production was 179 mg/L.

SYNTHESIZING A WELL-ALIGNED CARBON NANOTUBE FOREST WITH HIGH QUALITY VIA THE NEBULIZED SPRAY PYROLYSIS METHOD BY OPTIMIZING ULTRASONIC FREQUENCY

ZHI YANG,HUAGUI NIE,XUEMEI ZHOU,ZHEN YAO,SHAOMING HUANG,XIAOHUA CHEN 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2011 NANO Vol.6 No.4

Nebulized spray pyrolysis (NSP) offers ease of scaling into an industrial scale process method for large-scale CNT synthesis. In the method, ultrasonic frequency plays an important role in the formation of well-aligned carbon nanotubes (CNTs). In this work, we obtain well-aligned CNTs with high quality by optimizing ultrasonic frequency via the NSP method. SEM, TEM and HRTEM results show that the aligned CNTs obtained under an ultrasonic frequency of 1.8 MHz have good alignment, uniform nanotube length (~200 μm), high density and no trace of other carbon nanoparticles. The Raman spectra result further confirms that the aligned CNTs have a high graphitization degree. Furthermore, we find that ultrasonic frequency is an important factor in determining the nanotube diameter. The higher the ultrasonic frequency, the smaller the nanotube diameter. This rule may be very helpful in the preparation of large-scale well-aligned CNTs with high quality and diameter-controlled at low cost.

INVESTIGATION OF HOMOLOGOUS SERIES AS PRECURSORY HYDROCARBONS FOR ALIGNED CARBON NANOTUBE FORMATION BY THE SPRAY PYROLYSIS METHOD

ZHI YANG,HUAGUI NIE,XUEMEI ZHOU,ZHEN YAO,SHAOMING HUANG,XIAOHUA CHEN 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2011 NANO Vol.6 No.3

The precursory carbon source is one of the key parameters which govern the formation of carbon nanotubes (CNTs). In this work, by selecting four homologous series, namely n-pentane, n-hexane, n-heptane and n-octane, as investigated targets, we comparatively study the relationship between thermodynamic properties of the precursory carbon source and formation of aligned CNTs. We find that all of these alkanes are favored for the growth of aligned CNTs in a suitable growth environment. But only n-heptane can yield the aligned CNTs with relatively high quality, high yield and narrow diameter distribution. Furthermore, after considering the link between thermodynamic properties of the precursory carbon source and the morphology characteristic of the nanotube samples, we find that the Gibbs free energy and formation enthalpy of precursory carbon sources play critical roles in the nanotube formation. In additions some possible explanations are proposed to better understand these phenomena. These rules will be very helpful in making clearer the formation mechanism from the precursory carbon sources to the CNTs, and preparing large-scale aligned CNTs with diameter control at low cost.

In vitro rapid propagation technology system of Dendrobium moniliforme (L.) Sw., a threatened orchid species in China

Liu Xu,Sun Liyong,Nie Tangjie,Chen Yao,Yin Zengfang 한국식물생명공학회 2023 Plant biotechnology reports Vol.17 No.3

Dendrobium moniliforme is a threatened and medicinal orchid species in China. The establishment of in vitro rapid propagation technology system will facilitate preservation and utilization of germplasm resources in D. moniliforme. In this study, the effects of different plant growth regulators (PGRs) on seed germination, proliferation of cluster shoots, rooting of shoots were tested under asymbiotic culture condition, and the best acclimatization condition of plantlets was screened. Our research results were shown as follows: germination rate (GR) was significantly increased by adding N6-benzyladenine (BA, 0.1 mg/L) during asymbiotic culture. In Murashige and Skoog (MS) medium supplemented with α-naphthaleneacetic acid (NAA, 1.0 mg/L) and BA (1.0 mg/L), the proliferation coefficient of cluster shoots was 6.1 times comparing with the control group. The MS medium with NAA (0.5 mg/L) and indole-3-butyric acid (IBA, 0.5 mg/L) promoted the highest rooting rate (RR). For plantlet transplanting, the equal mixing volume ratio of pine bark, turfy soil, and peanut shells was the best substrate. In a word, this rapid propagation system provides strong technical support for D. moniliforme to expand proliferation and germplasm resource protection.

韓國李圭景《詩家點燈ㆍ律陶》自然生命意識初論

沈文凡(Shen Wen fan),??(Nie Yao) 동아인문학회 2010 동아인문학 Vol.18 No.-

Our ancient Poetry Talks were about the discussion of poem, poet, the orgin of the poem, the comment of the poem and so on, which gradually become more and more important in the study of ancient poems. Poetry Talks in Korea collect a large number of our ancient poems which are better literature value and historical status and the worthy of our attention is its unique comments. This thesis selects the “SHI JIA DIAN DENG LU TAO” which was wrriten by Li Gui-jing as study object and takes nature as the central idea which revolves the clue of real, aesthetic and perfect as investigation and argumnetation. Tao Yuan-ming is an natural poet and philosopher and his poems are full of emotion and logic. Many writers inherits Tao Yuan-ming’s poems and thinking. This thesis focuses the natural life consciousness and cultural contents of the poems of Tao Yuan-ming for the purpose of addition on the study of the poems’ of Tao Yuan-ming.

Lifetime Prediction and Aging Behaviors of Nitrile Butadiene Rubber under Operating Environment of Transformer

Qian, Yi-hua,Xiao, Hong-zhao,Nie, Ming-hao,Zhao, Yao-hong,Luo, Yun-bai,Gong, Shu-ling The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.2

Based on the actual operating environment of transformer, the aging tests of nitrile butadiene rubber (NBR) were conducted systematically under four conditions: in air, in transform oil, under compression in air and under compression in transform oil to studythe effect of high temperature, transform oil and compression stress simultaneously on the thermal aging behaviors of nitrile butadiene rubber and predict the lifetime. The effects of liquid media and compression stress simultaneously on the thermal aging behaviors of nitrile butadiene rubber were studied by using characterization methods such as IR spectrosc-opy, thermogravimetric measurements, Differential Scanning Calorimetry (DSC) measurements and mechanical property measurements. The changes in physical properties during the aging process were analyzed and compared. Different aging conditions yielded materials with different properties. Aging at $70^{\circ}C$ under compression stress in oil, the change in elongation at break was lower than that aging in oil, but larger than that aging under compression in air. The compression set or elongation at break as evaluation indexes, 50% as critical value, the lifetime of NBR at $25^{\circ}C$ was predicted and compared. When aging under compression in oil, the prediction lifetime was lower than in air and under compression in air, and in oil. It was clear that when predicting the service lifetime of NBR in oil sealing application, compression and media liquid should be involved simultaneously. Under compression in oil, compression set as the evaluation index, the prediction lifetime of NBR was shorter than that of elongation at break as the evaluation index. For the life prediction of NBR, we should take into account of the performance trends of NBR under actual operating conditions to select the appropriate evaluation index.