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A systematic approach in load disaggregation utilizing a multi-stage classification algorithm for consumer electrical appliances classification

Chuan Choong YANG, Chit Siang SOH, Vooi Voon YAP

《能源前沿（英文）》 2019年 第13卷 第2期   页码 386-398 doi: 10.1007/s11708-017-0497-z

摘要： The potential to save energy in existing consumer electrical appliances is very high. One of the ways to achieve energy saving and improve energy use awareness is to recognize the energy consumption of individual electrical appliances. To recognize the energy consumption of consumer electrical appliances, the load disaggregation methodology is utilized. Non-intrusive appliance load monitoring (NIALM) is a load disaggregation methodology that disaggregates the sum of power consumption in a single point into the power consumption of individual electrical appliances. In this study, load disaggregation is performed through voltage and current waveform, known as the - trajectory. The classification algorithm performs cropping and image pyramid reduction of the - trajectory plot template images before utilizing the principal component analysis (PCA) and the -nearest neighbor ( -NN) algorithm. The novelty of this paper is to establish a systematic approach of load disaggregation through - trajectory-based load signature images by utilizing a multi-stage classification algorithm methodology. The contribution of this paper is in utilizing the “ -value,” the number of closest data points to the nearest neighbor, in the -NN algorithm to be effective in classification of electrical appliances. The results of the multi-stage classification algorithm implementation have been discussed and the idea on future work has also been proposed.

关键词： load disaggregation     voltage-current (V-I) trajectory     multi-stage classification algorithm     principal component analysis (PCA)     k-nearest neighbor (k-NN)    

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Development and advances in modular multilevel converter based HVDC projects in China

《工程管理前沿（英文）》   页码 183-189 doi: 10.1007/s42524-022-0248-7

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关键词： high voltage direct current     power converter     power systems     renewable energy     ultra-high voltage    

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Processing of high-precision ceramic balls with a spiral V-groove plate

Ming FENG,Yongbo WU,Julong YUAN,Zhao PING

《机械工程前沿（英文）》 2017年 第12卷 第1期   页码 132-142 doi: 10.1007/s11465-017-0436-z

摘要：

As the demand for high-performance bearings gradually increases, ceramic balls with excellent properties, such as high accuracy, high reliability, and high chemical durability used, are extensively used for high-performance bearings. In this study, a spiral V-groove plate method is employed in processing high-precision ceramic balls. After the kinematic analysis of the ball-spin angle and enveloped lapping trajectories, an experimental rig is constructed and experiments are conducted to confirm the feasibility of this method. Kinematic analysis results indicate that the method not only allows for the control of the ball-spin angle but also uniformly distributes the enveloped lapping trajectories over the entire ball surface. Experimental results demonstrate that the novel spiral V-groove plate method performs better than the conventional concentric V-groove plate method in terms of roundness, surface roughness, diameter difference, and diameter decrease rate. Ceramic balls with a G3-level accuracy are achieved, and their typical roundness, minimum surface roughness, and diameter difference are 0.05, 0.0045, and 0.105 mm, respectively. These findings confirm that the proposed method can be applied to high-accuracy and high-consistency ceramic ball processing.

关键词： bearing     ceramic ball     spiral V-groove     kinematic analysis     trajectory    

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Accounting for the uncertainties in the estimation of average shear wave velocity using – correlations

《结构与土木工程前沿（英文）》 2021年 第15卷 第5期   页码 1199-1208 doi: 10.1007/s11709-021-0749-1

摘要： Site-specific seismic hazard analysis is crucial for designing earthquake resistance structures, particularly in seismically active regions. Shear wave velocity ( V S) is a key parameter in such analysis, although the economy and other factors restrict its direct field measurement in many cases. Various V S–SPT– N correlations are routinely incorporated in seismic hazard analysis to estimate the value of V S. However, many uncertainties question the reliability of these estimated V S values. This paper comes up with a statistical approach to take care of such uncertainties involved in V S calculations. The measured SPT– N values from all the critical boreholes were converted into statistical parameters and passed through various correlations to estimate V S at different depths. The effect of different soil layers in the boreholes on the Vs estimation was also taken into account. Further, the average shear wave velocity of the top 30 m soil cover ( V S30) is estimated after accounting for various epistemic and aleatoric uncertainties. The scattering nature of the V S values estimated using different V S– N correlations was reduced significantly with the application of the methodology. Study results further clearly demonstrated the potential of the approach to eliminate various uncertainties involved in the estimation of V S30 using general and soil-specific correlations.

关键词： uncertainties     V S– N correlations     V S30     SPT data     statistical methodology    

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一种低电流纹波的低压大电流DC-DC变换器的研究

王萍,孙栩,宋良瑜

《中国工程科学》 2005年 第7卷 第4期   页码 59-63

摘要：

通过n个倍流整流结构交错并联方式用以进一步减小纹波电流。给出了电路的开关信号波形和仿真模型，并使用Pspice仿真软件对该模型进行仿真，取得满意效果。最后通过实验验证。这种结构特别适用于通信设备、计算机、宇航等领域的电源。

关键词： 低压大电流DC-DC变换器     倍流整流     交错并联    

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Experimental study of pollution effect on the behavior of high voltage insulators under alternative current

Hani BENGUESMIA, Nassima M’ZIOU, Ahmed BOUBAKEUR

《能源前沿（英文）》 2021年 第15卷 第1期   页码 213-221 doi: 10.1007/s11708-017-0479-1

摘要： In this paper, the impact of the conductivity and the distribution of pollution on the behavior of the high voltage insulator cap and pin 1512L, artificially polluted is described. An experimental model in form of a disc is proposed. This experimental model reproduces the real model which is the 1512L insulator. Besides, a comparative study is presented. For this comparative study, different solutions are adopted to s`imulate the pollution (containing NaCl+ distilled water) that has different conductivities for a discontinuous distribution of the pollution on the insulator under an AC voltage. Furthermore, the influence of the pollution on the flashover voltage and the leakage current is studied. Finally, the behavior of real and experimental model of the insulator is investigated.

关键词： 1512L insulator     circular model     artificial pollution     flashover     leakage current     discontinuous pollution     high voltage    

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Elasto-plastic fatigue crack growth analysis of plane problems in the presence of flaws using XFEM

SHEDBALE,I. V. SINGH,B. K. MISHRA

《结构与土木工程前沿（英文）》 2015年 第9卷 第4期   页码 420-440 doi: 10.1007/s11709-015-0305-y

摘要： In this paper, elasto-plastic XFEM simulations have been performed to evaluate the fatigue life of plane crack problems in the presence of various defects. The stress-strain response of the material is modeled by Ramberg-Osgood equation. The von-Mises failure criterion has been used with isotropic hardening. The -integral for two fracture modes (mode-I and mode-II) is obtained by decomposing the displacement and stress fields into their symmetric and antisymmetric parts, then individual stress intensity factors are extracted from -integral. The fatigue life obtained by EPFM is found quite close to that obtained by LEFM.

关键词： XFEM     von-Mises yield criterion     isotropic hardening     fatigue crack growth     J-integral    

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power quality conditioner based on a three-level NPC inverter using fuzzy control techniques for all voltage

Salim CHENNAI,M-T BENCHOUIA

《能源前沿（英文）》 2014年 第8卷 第2期   页码 221-239 doi: 10.1007/s11708-014-0317-7

摘要： This paper presents a novel and efficient control scheme for unified power quality conditioner (UPQC) based on three-level neutral point clamped (NPC) inverter using fuzzy logic techniques. The proposed UPQC is capable of mitigating source current harmonics and compensate all voltage disturbances such as voltage sags, swells, unbalances and harmonics. It is designed by the integration of series and shunt active filters (AFs) sharing a common DC bus capacitor. The DC voltage is maintained constant using proportional integral voltage controller. The synchronous reference frame (SRF) theory is used to get the reference signals for shunt active power filters (APFs) and the power reactive theory (p-q theory) for series APFs. The shunt and series APF reference signals derived from the control algorithm and sensed signals are injected in two controllers to generate switching signals. To improve the UPQC capability, fuzzy logic techniques are introduced to control the series APF. The performances of the proposed UPQC system are evaluated in terms of power factor correction, mitigation of voltage or current harmonics and all other voltage disturbances compensation using Matlab-Simulink software and SimPowerSystem toolbox. The simulation results illustrate the performance of the proposed UPQC at the common connection point of the nonlinear load to improve the power energy quality.

关键词： three-level neutral point clamped (NPC) inverter     unified power quality conditioner (UPQC)     current harmonics mitigation     fuzzy logic controller     voltage disturbance compensation     shunt active filter     series active filter     power quality energy improvement    

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Role of Akkermansia muciniphila in the development of nonalcoholic fatty liver disease: current knowledge

《医学前沿（英文）》 2022年 第16卷 第5期   页码 667-685 doi: 10.1007/s11684-022-0960-z

摘要： Nonalcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome and a common cause of liver cirrhosis and cancer. Akkermansia muciniphila (A. muciniphila) is a next-generation probiotic that has been reported to improve metabolic disorders. Emerging evidence indicates the therapeutic potential of A. muciniphila for NAFLD, especially in the inflammatory stage, nonalcoholic steatohepatitis. Here, the current knowledge on the role of A. muciniphila in the progression of NAFLD was summarized. A. muciniphila abundancy is decreased in animals and humans with NAFLD. The recovery of A. muciniphila presented benefits in preventing hepatic fat accumulation and inflammation in NAFLD. The details of how microbes regulate hepatic immunity and lipid accumulation in NAFLD were further discussed. The modulation mechanisms by which A. muciniphila acts to improve hepatic inflammation are mainly attributed to the alleviation of inflammatory cytokines and LPS signals and the downregulation of microbiota-related innate immune cells (such as macrophages). This review provides insights into the roles of A. muciniphila in NAFLD, thereby providing a blueprint to facilitate clinical therapeutic applications.

关键词： Akkermansia muciniphila     NAFLD     NASH     steatosis     inflammation    

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Novel method for the preparation of Cs-containing FAU(Y) catalysts for aniline methylation

Shaposhnik, Marina V. Belova, Boris A. Kolozhvari, Irina I. Ivanova

《化学科学与工程前沿（英文）》 2018年 第12卷 第1期   页码 70-76 doi: 10.1007/s11705-017-1694-3

摘要： Cs-containing FAU(Y)-type zeolite catalysts were prepared by conventional and novel ion exchange procedures followed by incipient wetness impregnation with CsOH. The novel ion exchange procedure involved hydrothermal treatment of NaY zeolite in aqueous solution of CsCl at 140–200 °C for 6–24 h. The samples were characterized by low-temperature nitrogen adsorption, X-ray fluorescence analysis, X-ray powder diffraction, scanning electron microscopy, Na, Al and Cs magic angle spinning nuclear magnetic resonance, CO and NH -Temperature programmed desorption. The results show that hydrothermal treatment at 200 °C allows to obtain higher degrees of ion-exchange (up to 83%) with respect to conventional method giving maximum 66%–69%. Catalytic properties of Cs-containing FAU(Y) were studied in aniline methylation. The yield of -methylaniline is shown to correlate with catalyst’s basicity. The best catalyst performance was achieved over the catalyst with the highest ion-exchange degree impregnated with CsOH. The selectivity to -methylaniline over this catalyst reached 96.4%.

关键词： FAU(Y) zeolite     ion exchange with cesium     aniline alkylation     N-methylaniline    

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Series transformer based diode-bridge-type solid state fault current limiter

Amir HEIDARY,Hamid RADMANESH,Seyed Hamid FATHI,G. B. GHAREHPETIAN

《信息与电子工程前沿（英文）》 2015年 第16卷 第9期   页码 769-784 doi: 10.1631/FITEE.1400428

摘要： We propose a novel series transformer based diode-bridge-type solid state fault current limiter (SSFCL). To control the fault current, a series RLC branch is connected to the secondary side of an isolation series transformer. Based on this RLC branch, two current limiting modes are created. In the first mode, R and C are bypassed via a paralleled power electronic switch (insulated-gate bipolar transistor, IGBT) and L remains connected to the secondary side of the transformer as a DC reactor. In the second mode, the series reactor impedance is not enough to limit the fault current. In this case, the fault current can be controlled by selecting a proper on-off duration of the parallel IGBT, across the series damping resistor ( ) and capacitor, which inserts high impedance into the line to limit the fault current. Then, by controlling the magnitude of the DC reactor current, the fault current is reduced and the voltage of the point of common coupling (PCC) is kept at an acceptable level. In addition, in the new SSFCL, the series RC branch, connected in parallel with the IGBT, serves as a snubber circuit for decreasing the transient recovery voltage (TRV) of the IGBT during on-off states. Therefore, the power quality indices can be improved. The measurement results of a built prototype are presented to support the simulation and theoretical studies. The proposed SSFCL can limit the fault current without any delay and successfully smooth the fault current waveform.

关键词： Solid state fault current limiter (SSFCL)     Power quality     Voltage sag     Point of common coupling (PCC)     Isolation transformer    

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Mechanisms of connective tissue formation and blocks of mitogen activated protein kinase

Irina A SHURYGINA, Michael G SHURYGIN, Nataliya I AYUSHINOVA, Galina B GRANINA, Nikolay V ZELENIN

《化学科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 232-237 doi: 10.1007/s11705-012-1286-1

摘要： Ninety male Wistar rats were selected under the “Guide for the Care and Use of Laboratory Animals” for skin-muscle wound models. Three groups of animals were examined respectively for inoculation of inhibitor of p38 MAPK (mitogen activated protein kinase) SB 203580 and JNK inhibitor SP 600125, and a control. Light microscopy, immunohistochemistry, and tensometry revealed that the inhibition of p38 or JNK cascades have modified the formation of the connective tissue scar. The degree of connective tissue growth in the area of surgical wound had been significantly reduced by the end of observation (30 d) as the SB 203580 was applied (% volume of collagen 43.60 (41.05 – 60.15) 73.54 (66.87 – 78.01) in control, = 0.002). Conversely, when we have applied the JNK blocker, the density of collagen in scar tissue increased (78.14 (72.77 – 81.14), = 0.022 control). SB203580 inhibits the expression of p38, c-Jun and c-Fos. When we have used the JNK blocker, the expression of c-Fos and c-Jun decreased, but the expression of p38 increased. This determines the high functional activity of fibroblasts after using SP 600125. Obtained results show the importance of studying regulators of cell differentiation as potential drugs, which significantly affect the outcome of the pathological processes.

关键词： connective tissue     mitogen activated protein kinase (MAPK)     p38     JNK    

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Etiology of invasive candidosis agents in Russia: a multicenter epidemiological survey

null

《医学前沿（英文）》 2018年 第12卷 第1期   页码 84-91 doi: 10.1007/s11684-017-0612-x

摘要：

A multicenter prospective epidemiological survey on the etiologic agents of invasive candidosis was conducted in Russia in the period of 2012–2014. Samples were collected from 284 patients with invasive candidosis and Candida species isolated by culture. The species were identified by DNA sequencing and MALDI-TOF mass-spectrometry. A total of 322 isolates were recovered, in which 96% of Сandida species belonged to six major species, namely, C. albicans (43.2%), C. parapsilosis (20.2%), C. glabrata (11.5%), C. tropicalis (9.6%), C. krusei (6.2%), and C. guilliermondii (5.3%). Most Candida species were isolated from blood samples (83.23%). Notably, the prevalence rate of C. albicans reduced from 52.38% to 32.79% (2012 vs. 2014) (P=0.01) whereas that of non-C. albicans increased from 47.62% (2012) to 67.21% (2014) (P<0.01). Species distribution differed among geographical regions; specifically, the prevalence rate of C. albicans as an etiologic agent of invasive candidosis in Siberian Federal region was significantly higher than that in other Federal regions. Results indicated a shift from C. albicans to non-C. albicans. Therefore, a detailed investigation on the contributing factors and appropriate treatment of invasive candidosis is needed.

关键词： prevalence     &Scy     andida species     invasive candidosis     nosocomial     etiology     MALDI-TOF mass-spectrometry     candidemia    

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Fatigue crack growth simulations of 3-D linear elastic cracks under thermal load by XFEM

Himanshu PATHAK,Akhilendra SINGH,I.V. SINGH,S. K. YADAV

《结构与土木工程前沿（英文）》 2015年 第9卷 第4期   页码 359-382 doi: 10.1007/s11709-015-0304-z

摘要： This paper deals with the fatigue crack growth simulations of three-dimensional linear elastic cracks by XFEM under cyclic thermal load. Both temperature and displacement approximations are extrinsically enriched by Heaviside and crack front enrichment functions. Crack growth is modelled by successive linear extensions, and the end points of these linear extensions are joined by cubic spline segments to obtain a modified crack front. Different crack geometries such as planer, non-planer and arbitrary spline shape cracks are simulated under thermal shock, adiabatic and isothermal loads to reveal the sturdiness and versatility of the XFEM approach.

关键词： 3-D cracks     fatigue life     Paris law     thermal load     XFEM    

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基于V/F的智能多路数据采集系统及串口通信

贾贵玺,李洪凤,齐炜

《中国工程科学》 2004年 第6卷 第11期   页码 58-62

摘要：

智能多路数据采集系统实现了多路温度采集与检测，利用仪用放大器AD620进行信号放大，采用LM331型电压-频率转换器进行电量转换，采用89S52单片机进行数据采集及存储并用Visual Basic 6.0实现单片机与PC机的通信；最后给出了智能多路数据采集系统在梅江小区综合办公楼生态能源示范系统的应用数据。

关键词： LM331型电压-频率转换器     Visual Basic 6.0     串行通信    

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标题 作者 时间 类型 操作

A systematic approach in load disaggregation utilizing a multi-stage classification algorithm for consumer electrical appliances classification

Chuan Choong YANG, Chit Siang SOH, Vooi Voon YAP

期刊论文

Development and advances in modular multilevel converter based HVDC projects in China

期刊论文

Processing of high-precision ceramic balls with a spiral V-groove plate

Ming FENG,Yongbo WU,Julong YUAN,Zhao PING

期刊论文

Accounting for the uncertainties in the estimation of average shear wave velocity using – correlations

期刊论文

一种低电流纹波的低压大电流DC-DC变换器的研究

王萍,孙栩,宋良瑜

期刊论文

Experimental study of pollution effect on the behavior of high voltage insulators under alternative current

Hani BENGUESMIA, Nassima M’ZIOU, Ahmed BOUBAKEUR

期刊论文

Elasto-plastic fatigue crack growth analysis of plane problems in the presence of flaws using XFEM

SHEDBALE,I. V. SINGH,B. K. MISHRA

期刊论文

power quality conditioner based on a three-level NPC inverter using fuzzy control techniques for all voltage

Salim CHENNAI,M-T BENCHOUIA

期刊论文

Role of Akkermansia muciniphila in the development of nonalcoholic fatty liver disease: current knowledge

期刊论文

Novel method for the preparation of Cs-containing FAU(Y) catalysts for aniline methylation

Shaposhnik, Marina V. Belova, Boris A. Kolozhvari, Irina I. Ivanova

期刊论文

Series transformer based diode-bridge-type solid state fault current limiter

Amir HEIDARY,Hamid RADMANESH,Seyed Hamid FATHI,G. B. GHAREHPETIAN

期刊论文

Mechanisms of connective tissue formation and blocks of mitogen activated protein kinase

Irina A SHURYGINA, Michael G SHURYGIN, Nataliya I AYUSHINOVA, Galina B GRANINA, Nikolay V ZELENIN

期刊论文

Etiology of invasive candidosis agents in Russia: a multicenter epidemiological survey

null

期刊论文

Fatigue crack growth simulations of 3-D linear elastic cracks under thermal load by XFEM

Himanshu PATHAK,Akhilendra SINGH,I.V. SINGH,S. K. YADAV

期刊论文

基于V/F的智能多路数据采集系统及串口通信

贾贵玺,李洪凤,齐炜

期刊论文