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      • KCI등재

        Learning Probabilistic Kernel from Latent Dirichlet Allocation

        ( Qi Lv ),( Lin Pang ),( Xiong Li ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.6

        Measuring the similarity of given samples is a key problem of recognition, clustering, retrieval and related applications. A number of works, e.g. kernel method and metric learning, have been contributed to this problem. The challenge of similarity learning is to find a similarity robust to intra-class variance and simultaneously selective to inter-class characteristic. We observed that, the similarity measure can be improved if the data distribution and hidden semantic information are exploited in a more sophisticated way. In this paper, we propose a similarity learning approach for retrieval and recognition. The approach, termed as LDA-FEK, derives free energy kernel (FEK) from Latent Dirichlet Allocation (LDA). First, it trains LDA and constructs kernel using the parameters and variables of the trained model. Then, the unknown kernel parameters are learned by a discriminative learning approach. The main contributions of the proposed method are twofold: (1) the method is computationally efficient and scalable since the parameters in kernel are determined in a staged way; (2) the method exploits data distribution and semantic level hidden information by means of LDA. To evaluate the performance of LDA-FEK, we apply it for image retrieval over two data sets and for text categorization on four popular data sets. The results show the competitive performance of our method.

      • Diagnosis Value of Membrane Glycolipids Biochemistry Index in Intracranial and Gastrointestinal Tumors

        Lv, Jun,Lv, Can-Qun,Mei, Ping,Qi, Shi-Mei Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.7

        The diagnostic value of membrane glycolipid biochemistry index, the lipid-bound sialic acid (LSA) and total sialic acid (TSA) in cerebrospinal fluid (CSF) was evaluated in 30 intracranial and 65 gastrointestinal tumors. The plasma LSA, TSA and red cell membrane sialic acid (R-SA) in were determined according to the method of Sevenmerhulm. Our results showed that the levels of LSA and TSA in CSF of intracranial tumor patients was higher than that of normal group(p<0.01). The concentration of TSA and LSA in patients with malignant glioma was higher than that of benign meningioma patients(P<0.01). No significance was found between intracranial halmatoma patients and normal control group for levels of membrane glycolipids (p>0.05). Results also found that the plasma LSA, TSA and R-SA of gastric carcinoma were significantly higher than those of control group (p<0.05); while no significant difference was found in the plasma LSA, TSA and R-SA levels between chronic gastritis, gastrohelcoma and normal control group (p>0.05). Plasma LSA, TSA and R-SA levels of gastric carcinoma patient were significantly higher than those of chronic gastritis patients and gastrohelcoma patients(p<0.05). It was also found that plasma LSA, TSA and R-SA contents were significantly higher in large intestine carcinoma patients than in benign in stestine tumor patients (p<0.05) while no significant difference was found between intestine benign tumor and normal control group (p>0.05). The levels of LSA, TSA and R-SA were obviously higher in the patients with metastasis than in the ones without (p<0.05.) The membrane glycolipid biochemistry index LSA and TSA in CSF are sensive markers for diagnosing intracranial tumors. For gastrointestinal malignant tumors the plasma LSA TSA and red blood cell membrane SA may be considered as auxiliary indicators for diagnosis. They can be used for distinguishing benign from malignant tumors.

      • KCI등재

        Inhibition of microRNA-214 promotes epithelial mesenchymal transition process and induces interstitial cystitis in postmenopausal women by upregulating Mfn2

        Jian-Wei Lv,Wei Wen,Chen Jiang,Qi-Bo Fu,Yin-Jun Gu,Ting-Ting Lv,Zhen-Dong Li,Wei Xue 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

        Our study aims to investigate the roles that microRNA-214 (miR-214) plays in the epithelial mesenchymal transition (EMT) process and the development of interstitial cystitis (IC) in postmenopausal women by targeting Mitofusin 2 (Mfn2). IC bladder tissues and adjacent normal bladder tissues were collected from postmenopausal women. Immunohistochemistry (IHC) staining was conducted. The target relationship between miR-214 and Mfn2 was determined by a dual luciferase reporter gene assay. Adipose-derived mesenchymal stem cells (ADMSCs) were extracted from postmenopausal rats and assigned to the blank, mimics, miR-214 inhibitors, mimics negative control (NC), inhibitors NC, Mfn2 siRNA, miR-214 inhibitors and Mfn2 siRNA groups. Exosomes secreted by transfected ADMSCs were instilled into the bladders of postmenopausal rats. The expression of miR-214 and Mfn2 mRNA and EMT markers was assessed by qRT-PCR and western blotting. It was confirmed that Mfn2 was the target gene of miR-214 in IC. Compared with the normal bladder tissues, miR-214 decreased, but Mfn2 increased in IC bladder tissues. Compared with the blank group, the expression of miR-214 and the expression levels of N-cadherin, Fibronectin, Twist1, Snail and Vimentin mRNA and protein increased, whereas the expression levels of Mfn2, E-cadherin and ZO-1 mRNA and protein decreased in the miR-214 mimics and Mfn2 groups. The expression of MiR-214 and the expression levels of N-cadherin, Fibronectin, Twist1, Snail and Vimentin mRNA and protein decreased, whereas the expression levels of Mfn2, E-cadherin and ZO-1 mRNA and protein increased in the miR-214 inhibitors group. Our findings indicate that the inhibition of miR-214 promotes the EMT process and contributes to bladder wall fibrosis by up-regulating Mfn2, thus leading to the occurrence of IC in postmenopausal women.

      • KCI등재

        한반도 식생의 녹색화에 대한 시계열적 분석

        Lv, Guan Ting,ZHUYONGYAN,Liu, Wei Qi,Huang, Xiao,Li, Cheng Lei,Cui, Gui Shan 한국기후변화학회 2019 한국기후변화학회지 Vol.10 No.4

        The vegetation is feedback on environmental change due to global warming. Also, the growth status of vegetation and the coverage area of vegetation are greatly affected by the environmental changes. The quantitative change of vegetation growth status is the primary task of vegetation response to environmental changes. In this study, the Global Inventory Modeling and Mapping Studies (GIMMS) based Normalized Difference Vegetation Index (NDVI) and CRU climate data are used to analyze the spatio‐temporal characteristics of vegetation greening evolution and its response to climate change from 1982 to 2015 in the Korean Peninsula by applying the partial correlation and trend analysis. The results show that the average NDVI value of the Korean Peninsula in the period 1982‐2015 was 0.68, among which the average NDVI in North Korea and South Korea was 0.69 and 0.67, respectively. The NDVI of the Korean Peninsula between 1982 and 2015 increased by 0.6x10‐3 year‐1. The increasing trend prior to and after 1998 was 2.5×10‐3 year‐1 and 0.9×10‐3 year‐1, respectively. During the 1982‐2015 years, the NDVI of DPRK and South Korea have grown mainly with the trend of 0.2×10‐3 year‐1 and 1.1×10‐3 year‐1, respectively. According to the analysis of NDVI and climatic factors, the distribution of NDVI in the three‐time series of Korean Peninsula is consistent in spatial distribution. According to the results of partial correlation analysis of climate factor and NDVI distribution in Korean Peninsula, the region has significant partial correlation with temperature change. The climate factor of temperature is the main driver of NDVI change, which plays a key role in controlling NDVI change accumulation.

      • SCOPUSKCI등재

        Simulation and Experimental Analysis for Noise Reduction of a Scooter Gearbox

        Qi Zhang(장기),Jing Zhang(장정),Zhong Hua Liu(유충화),Jian Hua Lv(려건화),Zhen Qin(진진),Sung Ki Lyu(류성기) Korean Society for Precision Engineering 2018 한국정밀공학회지 Vol.35 No.8

        Nowadays, noise, vibration, and harshness (NVH) is a comprehensive issue related to manufacturing quality, it gives the purchaser the most direct and superficial feeling. Following economic development, the improvement of people’s living standards, and the expansion of the export market, it has become urgent to develop and produce some better NVH performance motorcycles. In this paper, the transmission of a scooter gearbox is modeled and analyzed by software. Then, the first helical gear pair of the gearbox was investigated through static analysis. Lastly, optimized modification was verified using B&K testing equipment in the semi-anechoic room. The comparison of the simulation to prototype during testing showed a good correlation, which means simulation optimization can greatly improve the research and development efficiency of the transmission system.

      • SCOPUSKCI등재

        Study on the Reduction of Gear Whine Noise in Diesel Engine Gear Train

        Qi Zhang(장기),Yong Bo Wang(왕용보),Jian Hua Lv(려건화),Zhong Gang Zhu(주중강),Zhen Qin(진진),Sung Ki Lyu(류성기) Korean Society for Precision Engineering 2019 한국정밀공학회지 Vol.36 No.9

        Noise, Vibration and Harshness (NVH) is a comprehensive issue of manufacturing quality that gives the purchaser a superficial feeling. The NVH performance of the vehicle has undoubtedly become an important factor and basis for consumers. When the internal combustion engine is working, it generates a strong noise thus making it necessary to reduce the vibration and noise. The noise of diesel engine is divided into acoustic and structural radiation noise according to different radiation paths. The structure radiated noise is mainly caused by the combustion noise and mechanical transmission noise, while mechanical transmission noise is mainly generated by the meshing gears in the diesel. This paper aims to solve the problem of a diesel engine abnormal gear whine noise under idling conditions with a combination of simulation and experiment. By gear micro-modification, the gear train whine noise is reduced by minimizing the PPTE of the gear train. The comparison of the simulation to benching testing shows a good correlation. It provides an optional solution to the modification proposal of the engine gear train, which uses the similar structure for the engine. Future work will dwell on a better understanding of the gear rattle noise, which will be discussed later.

      • SCIESCOPUSKCI등재

        Silane coupling agent assisting dopamine‑functionalized biomass porous carbons for enhanced adsorption of organic acids: effects of acid–alkali activation on microstructure

        Qi Wang,Yaying Lv,Tao Zhu 한국탄소학회 2021 Carbon Letters Vol.31 No.1

        Biomass porous carbons derived from Laminaria japonica were prepared by KOH and H3PO4 activation methods, respectively. The results indicated that the chemical activation had an apparent effect on the molecular framework and space of materials. To enhance the selective adsorption for organic acids, biomass carbons were modified by dopamine combined with N-(2-aminoethyl)-3-aminopropyltrimethoxysilane. The SEM and BET results illustrated the effect of the chemical activation approach on the morphology and porous texture. The biomass porous carbon using KOH activation method had the highest surface area (up to 1558 m2/ g). Compared with unmodified materials, the modified materials showed higher adsorption capacity for organic acids (27.90 μg/mL for chlorogenic acid and 25.47 μg/mL for caffeic acid). It was suggested that modification of porous carbons might be a viable pathway to increase the specific adsorption affinity and efficiency for organic acids in dried jujube samples.

      • KCI등재후보

        Joint Relay Selection and Resource Allocation for Cooperative OFDMA Network

        ( Linshu Lv ),( Qi Zhu ) 한국인터넷정보학회 2012 KSII Transactions on Internet and Information Syst Vol.6 No.11

        In this paper, the downlink resource allocation of OFDMA system with decode-and-forward (DF) relaying is investigated. A non-convex optimization problem maximizing system throughput with users` satisfaction constraints is formulated with joint relay selection, subcarrier assignment and power allocation. We first transform it to a standard convex problem and then solve it by dual decomposition. In particular, an Optimal resource allocation scheme With Time-sharing (OWT) is proposed with combination of relay selection, subcarrier allocation and power control. Due to its poor adaption to the fast-varying environment, an improved version with subcarrier Monopolization (OWM) is put forward, whose performance promotes about 20% compared with that of OWT in the fast-varying vehicular environment. In fact, OWM is the special case of OWT with binary time-sharing factor and OWT can be seen as the tight upper bound of the OWM. To the best of our knowledge, such algorithms and their relation have not been accurately investigated in cooperative OFDMA networks in the literature. Simulation results show that both the system throughput and the users` satisfaction of the proposed algorithms outperform the traditional ones.

      • KCI등재

        Enhanced separation for paraffin wax using CO2-responsive emulsions based on switchable hydrophilicity solvents

        Jie Qi,Xiaojiang Li,Xin Lv,Yang Ge,Jinyu Wang,Hongsheng Lu 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.110 No.-

        Wax precipitation leads to destructive harms in the exploitation and transportation of petroleum. Solventtreatments can remove paraffin wax easily but the separation of solvent relying on distillation is admittedinefficient. Aiming at enhancing the separation and recovery performance of paraffin wax, CO2-responsive emulsion (SHS/W emulsion) based on switchable hydrophilicity solvents (SHS) is adopted. Since the paraffin wax is dissolved, emulsified, and dispersed by SHS/W emulsion, SHS/W emulsion exhibitsbetter removal performance than SHS. The paraffin wax is recovered effectively upon introducingCO2, which attributes to the transformation of SHS from hydrophobic to hydrophilic state. Comparedwith the SHS system, the recovery of paraffin wax is improved obviously by introducing surfactantSpan80. Owing to the deprotonation of SHS by bubbling N2 and heating, 77.6% SHS is recycled after recoveringparaffin wax. Here, the recycled SHS can be used to realize the removal of paraffin wax again. Thus,it is a promising and alternative strategy for realizing the sustainable and rapid removal of paraffin wax inthe petroleum industry.

      • KCI등재

        Fault Detection for a Class of Closed-loop Hypersonic Vehicle System via Hypothesis Test Method

        Xunhong Lv,Yifan Fang,Zehui Mao,Bin Jiang,Ruiyun Qi 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.1

        This paper studies the fault detection problem for a class of hypersonic vehicle with actuator faults,disturbances and random noises. To handle the unknown disturbances, an unknown input Kalman filter (UIKF) ispresented to estimate the unknown system states and disturbances, simultaneously. Considering that the closed-loopstructure brings the robustness to the hypersonic vehicle, which could cover some faults, the Total Measurable FaultInformation Residual (ToMFIR) is employed as the fault detection residual. Moreover, to deal with the randomnoises, the hypothesis testing method is utilized to obtain the thresholds under some fault detection performances(false alarm rate and missing alarm rate). The fault detectability condition is also derived. Finally, the simulationsverify the effectiveness of the proposed fault detection method

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