A New Ambiguity Elimination Method for BSS Block Signals in Time Domain

Wei Zhao,Fengshan Wang,Yuehong Shen,Yuanyuan Wu,Zhigang Yuan,Pengcheng Xu,Pengcheng Xu,Yimin Wei,Wei Jian 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.11

This paper deals with the ambiguity problem of blind source separation (BSS) in the case where continuously received mixture signals are split in time and processed block by block. Due to the inherent permutation and scaling ambiguities of BSS, tying the separated components at each adjacent time blocks doesn’t recover the original source signals correctly in general. Inspired by the Permutation Method of reconstructing source signal blocks in time domain, a new ambiguity elimination approach is proposed in this paper. This method aims to concatenate the separated components in adjacent blocks by artificially setting contrast blocks for each adjacent time blocks. The core idea of this method is to utilize the associativity between components recovered from contrast blocks and corresponding adjacent blocks. Compared with Permutation Method, the main advantage of this new method consists in the fact that it is much more efficient in terms of separation quality and computational speed. Besides, a tradeoff can be adjusted between separation quality and computational speed by choosing different length of contrast blocks. Real-life experiments are performed to validate the performance of this method on the wireless communication system with two transmitting and receiving antennas.

The Effect of Inhibition of Uncaria rhynchophylla as an Inhibitor of Melanogenesis and an Antioxidant in B16F10 Melanoma Cells

Yuanyuan Dong(동원원),Young Min Woo(우영민),Ji Hyun Cha(차지현),Jae Young Cha(차재영),Nai Wei Lee(려내유),Min Woo Back(백민우),Joon-sung Park(박준성),Sang-Hyeon Lee(이상현),Jong-Myung Ha(하종명),Andre Kim(김안드레) 한국생명과학회 2020 생명과학회지 Vol.30 No.12

최근 모든 연령대의 사람들은 미용적인 이유로 더 밝은 피부를 원하고 있으며, 천연 제품은 화학적으로 합성된 화합물보다 더 많은 관심을 받고 있다. 조구등은 아시아에서 전통 한약재로 널리 사용되어 왔다. 새로운 피부미백제를 찾기 위해 본 연구에서는 조구등의 항산화 활성과 잠재적인 tyrosinase 억제 작용을 확인하였다. 조구등을 70% 에탄올로 추출하여 항산화 활성을 분석하고 tyrosinase 활성과 melanin 합성에 미치는 영향을 평가했다. 총 mRNA 발현은 RT-PCR을 사용하였다. 그 결과 조구등 추출물은 B16F10 세포에서 뛰어난 항산화 능력과 상당한 수준의 폴리페놀 및 플라보노이드 화합물을 함유하였다. 또한, 세포 내 tyrosinase 활성을 억제하고 처리된 세포에서 melanin의 양을 감소시켰다. Tyrosinase의 mRNA 발현은 1 mg/ml 농도에서 현저히 감소하였다. 이와 같은 결과는 조구등이 미백 효과가 있는 화장품의 천연 소재로 사용될 수 있는 높은 잠재력을 가지고 있음을 시사한다. Many people of all ages wish to have lighter skin for cosmetic reasons, and natural products attract more attention than chemically synthesized compounds. Uncaria rhynchophylla is widely used in Asia as a traditional herbal medicine. In order to find novel skin whitening agents, the present study evaluated the antioxidant activity and potential tyrosinase-inhibiting properties of U. rhynchophylla. Specifically, this study analyzed the antioxidant capacity of a 70% ethanolic extract of U. rhynchophylla as well as its effects on tyrosinase activity and melanin synthesis. Total mRNA levels were examined using reverse transcription polymerase chain reaction. The results revealed that U. rhynchophylla extracts exhibit great antioxidant capacity and significant levels of polyphenol and flavonoid compounds. U. rhynchophylla extracts can also powerfully inhibit tyrosinase activity. This same capacity was observed in melanoma B16F10 cells; that is, U. rhynchophylla extracts suppressed intracellular tyrosinase activity and reduced the amount of melanin in treated cells. In addition, a 1 mg/ml concentration of U. rhynchophylla extract significantly reduced the mRNA expression levels of tyrosinase. U. rhynchophylla extracts decrease tyrosinase and inhibit melanogenesis in B16F10 cells. This finding suggests that U. rhynchophylla has great potential as a natural whitening agent in skincare products.

Low-Complexity Hybrid Adaptive Blind Equalization Algorithm for High-Order QAM Signals

( Wei Rao ),( Changlong Lu ),( Yuanyuan Liu ),( Jianqiu Zhang ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.8

It is well known that the constant modulus algorithm (CMA) presents a large steady-state mean-square error (MSE) for high-order quadrature amplitude modulation (QAM) signals. In this paper, we propose a low-complexity hybrid adaptive blind equalization algorithm, which augments the CMA error function with a novel constellation matched error (CME) term. The most attractive advantage of the proposed algorithm is that it is computationally simpler than concurrent CMA and soft decision-directed (SDD) scheme (CMA+SDD), and modified CMA (MCMA), while the approximation of steady-state MSE of the proposed algorithm is same with CMA+SDD, and lower than MCMA. Extensive simulations demonstrate the performance of the proposed algorithm.

Mean Square Detectability of LTI Systems over Finite-State Digital Block-Fading Channels

Wei Chen,Yuanyuan Zou,Nan Xiao,Yugang Niu 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.2

This paper studies the mean square quadratic (MSQ) detectability for multi-output networked systemsover finite-state digital block-fading channels. The packet-loss rate of each digital fading channel depends on thechannel power gain, as well as packet length and power level used for transmission. A finite-state random processis introduced to model time-varying fading channels, which characterizes various configurations of physical communicationenvironment and/or different channel fading amplitudes. Necessary and sufficient conditions for MSQdetectability over finite-state Markov digital block-fading channels are given in the form of algebraic Riccati equationsor linear matrix inequalities (LMIs). The estimation gain is given as a function of estimated/observed channelstate. In addition, explicit conditions on network for MSQ detectability over finite-state independent identicallydistributed (i.i.d.) digital block-fading channels are presented in terms of the unstable poles of the multi-outputplant. Finally, an application to Gilbert-Elliott channels (GECs) is provided to demonstrate the derived results.

Nigrospora Species Associated with Various Hosts from Shandong Peninsula, China

( Yuanyuan Hao ),( Janith V. S. Aluthmuhandiram ),( K. W. Thilini Chethana ),( Ishara S. Manawasinghe ),( Xinghong Li ),( Mei Liu ),( Kevin D. Hyde ),( Alan J. L. Phillips ),( Wei Zhang ) 한국균학회 2020 Mycobiology Vol.48 No.3

Nigrospora is a monophyletic genus belonging to Apiosporaceae. Species in this genus are phytopathogenic, endophytic, and saprobic on different hosts. In this study, leaf specimens with disease symptoms were collected from host plants from the Shandong Peninsula, China. The fungal taxa associated with these leaf spots were studied using morphology and phylogeny based on ITS, TEF1, and TUB2 gene regions. In this article, we report on the genus Nigrospora with N. gorlenkoana, N. oryzae, N. osmanthi, N. rubi, and N. sphaerica identified with 13 novel host associations including crops with economic importance such as bamboo and Chinese rose.

Developmental Exposure to Di-(2-ethylhexyl) Phthalate Induces Cerebellar Granule Cell Apoptosis via the PI3K/AKT Signaling Pathway

Yuanyuan Fu,Jing Dong,Jianan Wang,Mingdan You,Lingling Wei,Hui Fu,Yuan Wang,Jie Chen 한국뇌신경과학회 2018 Experimental Neurobiology Vol.27 No.6

Di-(2-ethylhexyl) phthalate (DEHP) is an ubiquitous environmental contaminant because of its extensive use in plastics and its persistence. As an environmental endocrine disruptor, it is suspected to interfere with neurodevelopment in people. However, evidence of the effects of maternal DEHP exposure on cerebellar development in offspring is scarce. The objective of this study was to investigate maternal exposure to DEHP and its effect on apoptosis of cerebellar granule cells (CGCs) and related mechanisms. Pregnant Wistar rats were administrated DEHP (0, 30, 300 and 750 mg/kg/d) by gavage from gestational day (GD) 0 to postnatal day (PN) 21. Primary CGCs were also exposed to mono-(2-ethylhexyl) phthalate (MEHP), the main metabolite of DEHP, for 24 h with concentrations of 0, 25, 100 and 250 μM. The CGCs of male offspring from 300 and 750 mg/kg/d DEHP exposure groups showed significantly increased apoptosis. In addition, the PI3K/AKT signaling pathway was inhibited in the male offspring of the 300 and 750 mg/ kg/d DEHP exposure groups. However, effects on female pups were not obvious. Apoptosis was also elevated and the PI3K/AKT signaling pathway was inhibited after primary CGCs were exposed to MEHP. Furthermore, apoptosis was reduced after treatment with the PI3K/AKT signaling pathway activator, insulin-like growth factor (IGF) 1, and increased after treatment with LY294002, an inhibitor of the PI3K/AKT signaling pathway. These results suggested that maternal DEHP exposure induced apoptosis in the CGCs of male pups via the PI3K/AKT signaling pathway, and the apoptosis could be rescued by IGF1 and aggravated by LY294002.

Study on complex flow law near polymer flooding wellbores and adaptability evaluation of shaped charges

Jianguang Wei,Xidong Ren,Hongyan Shao,Yuanyuan Ma,Xuemei Liu,Xuesong Lin 한국자원공학회 2016 Geosystem engineering Vol.19 No.5

The flow law near polymer flooding wellbores under the condition of perforation is very complex and there are many types of shaped charges. In this study, a non-Darcy flow model near polymer flooding wellbores was given, and a flow experiment was carried out to measure the resistance coefficient, residual resistance coefficient, and flow viscosity of the polymer solution in porous media under the conditions of different permeability and different polymer molecular weight. According to the results of numerical simulation, this paper calculated the flow efficiency of different types of shaped charges and evaluated the adaptability of different charges under polymer flooding condition. The results of this study have an important significance for guiding the optimization of shaped charges and the optimization design of perforating parameters.

UV-grafting Coloration of Cotton and Wool Fabrics Using Bismethacrylated Quinizarin Dye

Dong, Yuanyuan,Zheng, Laijiu,Wei, Ju,Jang, Jinho 한국섬유공학회 2016 Fibers and polymers Vol.17 No.10

A novel bifunctional quinizarin dye possessing two photoactive methacrylate groups was synthesized by the reaction of quinizarin with methacryloyl chloride. The synthesized dye, a low substantive dye under the conventional dyeing process, can be photografted onto cotton and wool fabrics at room temperature without neutral salts, which makes it a novel coloration process of excellent environmental friendliness. The concurrent polymerization and grafting of the synthesized dye onto cotton or wool can be assisted by a photoinitiator and acrylic acid in the case of cotton grafting. Moreover, color yields of the grafted fabrics improved significantly with the photografting of the bifunctional dye. The bifunctional dye can be photopolymerized with the increase in UV energy to <TEX>$25J/cm^2$</TEX> and the oligomeric dye has a degree of polymerization of 5 or more. Furthermore, the color fastness properties of the grafted fabrics were superior to those of the dyed fabrics via exhaustion.

Bubble breakup dynamics and flow behaviors of a surface-functionalized nanocellulose based nanofluid stabilized foam in constricted microfluidic devices

Bing Wei,Yuanyuan Wang,Yangbing Wen,Xingguang Xu,Colin Wood,Lin Sun 한국공업화학회 2018 Journal of Industrial and Engineering Chemistry Vol.68 No.-

Nanocellulose was surface-functionalized toward the applications in enhanced oil recovery (EOR) as a green alternative. The focus of this paper is on the effect of this material based nanofluid (NF) on foam lamella stabilization through studying its bubble breakup dynamics and flow behaviors in constricted mircofluidic devices. The NF stabilized foam produced an improved flow resistance across the capillary largely due to the capillary trapped bubbles at the contraction. The “snap-off” caused the NF stabilized foam to produce finer textured bubbles, which can migrate readily forward to the deep porous media, as revealed by the pressure profiles.

An Interpretable Bearing Fault Diagnosis Model Based on Hierarchical Belief Rule Base

Boying Zhao,Yuanyuan Qu,Mengliang Mu,Bing Xu,Wei He 한국인터넷정보학회 2024 KSII Transactions on Internet and Information Syst Vol.18 No.5

Bearings are one of the main components of mechanical equipment and one of the primary components prone to faults. Therefore, conducting fault diagnosis on bearings is a key issue in mechanical equipment research. Belief rule base (BRB) is essentially an expert system that effectively integrates qualitative and quantitative information, demonstrating excellent performance in fault diagnosis. However, class imbalance often occurs in the diagnosis task, which poses challenges to the diagnosis. Models with interpretability can enhance decision-makers’ trust in the output results. However, the randomness in the optimization process can undermine interpretability, thereby reducing the level of trustworthiness in the results. Therefore, a hierarchical BRB model based on extreme gradient boosting (XGBoost) feature selection with interpretability (HFS-IBRB) is proposed in this paper. Utilizing a main BRB alongside multiple sub-BRBs allows for the conversion of a multi-classification challenge into several distinct binary classification tasks, thereby leading to enhanced accuracy. By incorporating interpretability constraints into the model, interpretability is effectively ensured. Finally, the case study of the actual dataset of bearing fault diagnosis demonstrates the ability of the HFS-IBRB model to perform accurate and interpretable diagnosis.