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Neuropeptide cholecystokinin:a key neuromodulator for hippocampal functions
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作者 Fengwen Huang Stephen Temitayo Bello 《Neural Regeneration Research》 SCIE CAS 2025年第7期1991-1992,共2页
Spatial memory is crucial for survival within external surroundings and wild environments.The hippocampus,a critical hub for spatial learning and memory formation,has received extensive investigations on how neuromodu... Spatial memory is crucial for survival within external surroundings and wild environments.The hippocampus,a critical hub for spatial learning and memory formation,has received extensive investigations on how neuromodulators shape its functions(Teixeira et al.,2018;Zhang et al.,2024).However,the landscape of neuromodulations in the hippocampal system remains poorly understood because most studies focus on classical monoamine neuromodulators,such as acetylcholine,serotonin,dopamine,and noradrenaline.The neuropeptides,comprising the most abundant neuromodulators in the central nervous system,play a pivotal role in neural information processing in the hippocampal system.Cholecystokinin(CCK),one of the most abundant neuropeptides,has been implicated in regulating various physiological and neurobiological statuses(Chen et al.,2019).CCK-A receptor(CCK-AR)and CCK-B receptors(CCK-BR)are two key receptors mediating the biological functions of CCK,both of which belong to class-A sevenfold transmembrane G protein-coupled receptors(Nishimura et al.,2015).CCK-AR preferentially reacts to sulfated CCK,whereas CCK-BR binds both CCK and gastrin with similar affinities(Ding et al.,2022).The expression patterns of CCK-AR and CCK-BR are distinct,implying that CCK has various functions in target regions.For instance,CCK-AR is widely expressed in the GI and brain subregions and is hence implicated in the control of digestive function and satiety regulation.Conversely,CCK-BR is abundantly and widely distributed in the central nervous system,which majorly regulates anxiety,learning,and memory(Ding et al.,2022).However,the roles of endogenous CCK and CCK receptors in regulating hippocampal function at electrophysiological and behavioral levels have received less attention. 展开更多
关键词 abundant functionS modulATOR
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Cosine-modulated window function-based staggered-grid finite-difference forward modeling 被引量:5
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作者 王建 孟小红 +2 位作者 刘洪 郑婉秋 贵生 《Applied Geophysics》 SCIE CSCD 2017年第1期115-124,191,共11页
The numerical dispersion and computational cost are high for conventional Taylor series expansion staggered-grid finite-difference forward modeling owing to the high frequency of the wavelets and the large grid interv... The numerical dispersion and computational cost are high for conventional Taylor series expansion staggered-grid finite-difference forward modeling owing to the high frequency of the wavelets and the large grid intervals. In this study, the cosine-modulated binomial window function (CMBWF)-based staggered-grid finite-difference method is proposed. Two new parameters, the modulated time and modulated range are used in the new window function and by adjusting these two parameters we obtain different characteristics of the main and side lobes of the amplitude response. Numerical dispersion analysis and elastic wavefield forward modeling suggests that the CMBWF method is more precise and less computationally costly than the conventional Taylor series expansion staggered-grid finite-difference method. 展开更多
关键词 Elastic wave staggered grid window function cosine modulate
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Analysis of the optical quality by determining the modulation transfer function for anterior corneal surface in myopes 被引量:6
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作者 Yan-Zhen Zheng, Yao-Yu Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2012年第2期196-201,共6页
AIM: To describe the characteristics of modulation transfer function (MTF) of anterior corneal surface, and obtain the the normal reference range of MTF at different spatial frequencies and optical zones of the anteri... AIM: To describe the characteristics of modulation transfer function (MTF) of anterior corneal surface, and obtain the the normal reference range of MTF at different spatial frequencies and optical zones of the anterior corneal surface in myopes. METHODS: Four hundred eyes from 200 patients were examined under SIRIUS corneal topography system. Phoenis analysis software was applied to simulate the MTF curves of anterior corneal surface at vertical and horizontal meridians at the 3, 4, 5, 6, 7mm optical zones of cornea. The MTF values at spatial frequencies of 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55 and 60 cycles/degree (c/d) were selected. RESULTS: The MTF curve of anterior corneal surface decreased rapidly from low to intermediate frequency (0-15cpd) at various optical zones of cornea, the value decreased to 0 slowly at higher frequency (>15cpd). With the increase of the optical zones of cornea, MTF curve decreased gradually. 3) In the range of 3 mm- 6 mm optical zones of the cornea, the MTF values measured at horizontal meridian were greater than the corresponding values at horizontal meridian of each spatial frequency, the difference was statistically significant (P<0.05). At 7 mm optical zones of cornea, the MTF values measured at horizontal meridian were less than the corresponding values at vertical meridian at 10-60 spatial frequencies (cpd), and the difference was statistically significant in 25, 30, 35, 40, 45, 50 cpd(P<0.05). CONCLUSION: MTF can be used to describe the imaging quality of optical systems at anterior corneal surface objectively in detail. 展开更多
关键词 modulation transfer function optical quality CORNEA point spread function optical transfer function phase transfer function
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GOMA:functional enrichment analysis tool based on GO modules 被引量:4
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作者 Qiang Huang Ling-Yun Wu +1 位作者 Yong Wang Xiang-Sun Zhang 《Chinese Journal of Cancer》 SCIE CAS CSCD 2013年第4期195-204,共10页
Analyzing the function of gene sets is a critical step in interpreting the results of high-throughput experiments in systems biology. A variety of enrichment analysis tools have been developed in recent years, but mos... Analyzing the function of gene sets is a critical step in interpreting the results of high-throughput experiments in systems biology. A variety of enrichment analysis tools have been developed in recent years, but most output a long list of significantly enriched terms that are often redundant, making it difficult to extract the most meaningful functions. In this paper, we present GOMA, a novel enrichment analysis method based on the new concept of enriched functional Gene Ontology (GO) modules. With this method, we systematically revealed functional GO modules, i.e., groups of functionally similar GO terms, via an optimization model and then ranked them by enrichment scores. Our new method simplifies enrichment analysis results by reducing redundancy, thereby preventing inconsistent enrichment results among functionally similar terms and providing more biologically meaningful results. 展开更多
关键词 GO ENRICHMENT analysis modules functionAL redundancy network RELATIONSHIPS
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Modulation transfer function characteristic of uniform-doping transmission-mode GaAs/GaAlAs photocathode 被引量:2
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作者 任玲 常本康 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第8期398-402,共5页
The resolution characteristic can be obtained by the modulation transfer function (MTF) of a GaAs/GaA1As photocathode. After establishing the theoretical model of GaAs(100)-oriented atomic configuration and the fo... The resolution characteristic can be obtained by the modulation transfer function (MTF) of a GaAs/GaA1As photocathode. After establishing the theoretical model of GaAs(100)-oriented atomic configuration and the formula for the ionized impurity scattering of the non-equilibrium carriers, this paper calculates the trajectories of photoelectrons in a photocathode. Thus the distribution of photoelectron spots on the emit-face is obtained, which is namely the point spread function. The MTF is obtained by Fourier transfer of the line spread function obtained from the point spread function. The MTF obtained from these calculations is shown to depend heavily on the electron diffusion length, and enhanced considerably by decreasing the electron diffusion length and increasing the doping concentration. Furthermore, the resolution is enhanced considerably by increasing the active-layer thickness, especially at high spatial frequencies. The best spatial resolution is 860 lp/mm, for the GaAs photocathode of doping concentration 1 ×10^19 cm 3 electron diffusion length 3.6 μm and the active-layer thickness 2 μm, under the 633-nm light irradiated. This research will contribute to the future improvement of the cathode's resolution for preparing a high performance GaAs photocathode, and improve the resolution of a low light level image intensifier. 展开更多
关键词 GaAs/GaAlAs photocathode uniform-doping modulation transfer function spatial res-olution
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A Method of Clustering Components into Modules Based on Products' Functional and Structural Analysis 被引量:1
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作者 孟祥慧 蒋祖华 郑迎飞 《Journal of Shanghai Jiaotong university(Science)》 EI 2006年第3期279-285,共7页
Modularity is the key to improving the cost-variety trade-off in product development. To achieve the functional independency and structural independency of modules, a method of clustering components to identify module... Modularity is the key to improving the cost-variety trade-off in product development. To achieve the functional independency and structural independency of modules, a method of clustering components to identify modules based on functional and structural analysis was presented. Two stages were included in the method. In the first stage the products’ function was analyzed to determine the primary level of modules. Then the objective function for modules identifying was formulated to achieve functional independency of modules. Finally the genetic algorithm was used to solve the combinatorial optimization problem in modules identifying to form the primary modules of products. In the second stage the cohesion degree of modules and the coupling degree between modules were analyzed. Based on this structural analysis the modular scheme was refined according to the thinking of structural independency. A case study on the gear reducer was conducted to illustrate the validity of the presented method. 展开更多
关键词 module identifying CLUSTERING functional independency structural independency genetic algorithm1
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Comparison of the retinal modulation transfer function between amblyopes successfully corrected and normal subjects
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作者 Xiao-Ming Huang, Guo-Xing Xu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2011年第3期284-285,共2页
AIM:To analyze the retinal modulation transfer function between amblyopes whose visual acuity was corrected to 5.0 and normal subjects at the same age. METHODS: RM-800 used to detect contrast sensitivity was adopted t... AIM:To analyze the retinal modulation transfer function between amblyopes whose visual acuity was corrected to 5.0 and normal subjects at the same age. METHODS: RM-800 used to detect contrast sensitivity was adopted to measure MTF of 96 amblyopes (96 eyes) whose visual acuity was corrected to 5.0 and 80 normal controls (80 eyes) at the same age under six interference fringes (IVA=0.06, 0.1, 0.2, 0.4, 0.6, 0.8). RESULTS: The functional values of amblyopes were significantly lower than those of normal subjects in every fringe (P<0.01), especially in medium and high frequency. CONCLUSION: For amblyopes, MTF was still abnormal after stopping the treatments. 展开更多
关键词 modulation transfer function amblyope Interference Fringe Visual Acuity
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Unbiased parameter estimation of continuous-time system based on modulating functions with input and output white noises
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作者 贺尚红 李旭宇 《Journal of Central South University》 SCIE EI CAS 2011年第3期773-781,共9页
An efficient unbiased estimation method is proposed for the direct identification of linear continuous-time system with noisy input and output measurements.Using the Gaussian modulating filters,by numerical integratio... An efficient unbiased estimation method is proposed for the direct identification of linear continuous-time system with noisy input and output measurements.Using the Gaussian modulating filters,by numerical integration,an equivalent discrete identification model which is parameterized with continuous-time model parameters is developed,and the parameters can be estimated by the least-squares (LS) algorithm.Even with white noises in input and output measurement data,the LS estimate is biased,and the bias is determined by the variances of noises.According to the asymptotic analysis,the relationship between bias and noise variances is derived.One equation relating to the measurement noise variances is derived through the analysis of the LS errors.Increasing the degree of denominator of the system transfer function by one,an extended model is constructed.By comparing the true value and LS estimates of the parameters between original and extended model,another equation with input and output noise variances is formulated.So,the noise variances are resolved by the set of equations,the LS bias is eliminated and the unbiased estimates of system parameters are obtained.A simulation example by comparing the standard LS with bias eliminating LS algorithm indicates that the proposed algorithm is an efficient method with noisy input and output measurements. 展开更多
关键词 continuous-time system unbiased parameter modulating functions noise
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Fuzzy image restoration using modulation transfer function
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作者 袁媛 Yi Yaohua Liu Juhua 《High Technology Letters》 EI CAS 2016年第4期461-469,共9页
The key difficulty of restoring a fuzzy image is to estimate its point spread function( PSF). In the paper,PSF is modelled based on modulation transfer function( MTF). The first step is calculating the image MTF. In t... The key difficulty of restoring a fuzzy image is to estimate its point spread function( PSF). In the paper,PSF is modelled based on modulation transfer function( MTF). The first step is calculating the image MTF. In the traditional slanted-edge method,a sub-block is always manually extracted from original image and its MTF will be viewed as the result of the whole image. However,handcraft extraction is inefficient and will lead to inaccurate results. Given this,an automatic MTF computation algorithm is proposed,which extracts and screens out all the effective sub-blocks and calculates their average MTF as the final result. Then,a two-dimensional MTF restoration model is constructed by multiplying the horizontal and vertical MTF,and it is combined with conventional image restoration methods to restore fuzzy image. Experimental results indicate the proposed method implementes a fast and accurate MTF computation and the MTF model improves the performance of conventional restoration methods significantly. 展开更多
关键词 fuzzy image modulation transfer function(MTF) slanted-edge method automatic computation MTF restoration model
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Intensity Correlation Function of a Single-Mode Laser Driven by Colored Cross-Correlation Noises in Modulation of a Bias Signal
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作者 HANLi-Bo CAOLi +1 位作者 YANGHong-Quan WUDa-Jin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4期666-670,共5页
By using the linear approximation method, the intensity correlation function is calculated for a single-mode laser modulated by a bias signal and driven by colored pump and quantum noises with colored cross-correlatio... By using the linear approximation method, the intensity correlation function is calculated for a single-mode laser modulated by a bias signal and driven by colored pump and quantum noises with colored cross-correlation. We found that, when the correlation time between the two noises is very short, the behavior of the intensity correlation function versus the time, in addition to decreasing monotonously, also exhibits several cases, such as one maximum, one minimum, and two extrema. When the correlation time between the two noises is very long, the behavior of the intensity correlation function exhibits oscillation and the envelope is similar to the case of short cross-correlation time. 展开更多
关键词 linear approximation method intensity correlation function bias signal modulation oscillation
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A new modulation transfer function for ocean wave spectra retrieval from X-band marine radar imagery
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作者 陈忠彪 张彪 +2 位作者 何宜军 丘仲锋 PERRIE William 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第5期1132-1141,共10页
When imaging ocean surface waves by X-band marine radar, the radar backscatter from the sea surface is modulated by the long surface gravity waves. The modulation transfer function (MTF) comprises tilt, hydrodynamic... When imaging ocean surface waves by X-band marine radar, the radar backscatter from the sea surface is modulated by the long surface gravity waves. The modulation transfer function (MTF) comprises tilt, hydrodynamic, and shadowing modulations. A conventional linear MTF was derived using HH-polarized radar observations under conditions of deep water. In this study, we propose a new quadratic polynomial MTF based on W-polarized radar measurements taken from heterogeneous nearshore wave fields. This new MTF is obtained using a radar-observed image spectrum and in situ buoy-measured wave frequency spectrum. We validate the MTF by comparing peak and mean wave periods retrieved from X-band marine radar image sequences with those measured by the buoy. It is shown that the retrieval accuracies of peak and mean wave periods of the new MTF are better than the conventional MTF. The results also show that the bias and root mean square errors of the peak and mean wave periods of the new MTF are 0.05 and 0.88 s, and 0.32 and 0.53 s, respectively, while those of the conventional MTF are 0.61 and 0.98 s, and 1.39 and 1.48 s, respectively. Moreover, it is also shown that the retrieval results are insensitive to the coefficients in the proposed MTF. 展开更多
关键词 X-band marine radar modulation transfer function ocean wave spectra
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Discovering the cellular-localized functional modules and modular interactions in response to liver cancer
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作者 朱晶 Guo Zheng +3 位作者 Yang Da Zhang Min Wang Jing Wang Chenguang 《High Technology Letters》 EI CAS 2008年第4期437-442,共6页
In this paper, we firstly identify the functional modules enriched with differentially expressed genes (DEGs) and characterized by biological processes in specific cellular locations, based on gene ontology (GO) a... In this paper, we firstly identify the functional modules enriched with differentially expressed genes (DEGs) and characterized by biological processes in specific cellular locations, based on gene ontology (GO) and microarray data. Then, we further define and filter disease relevant signature modules according to the ranking of the disease discriminating abilities of the pre-selected functional modules. At last, we analyze the potential way by which they cooperate towards human disease. Application of the proposed method to the analysis of a liver cancer dataset shows that, using the same false discovery rate ( FDR ) threshold, we can find more biologically meaningful and detailed processes by using the cellular localization information. Some biological evidences support the relevancy of our biological modules to the disease mechanism. 展开更多
关键词 MICROARRAY Gene Ontology functional module cellular location liver cancer
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Modulating J-V hysteresis of planar perovskite solar cells and mini-modules via work function engineering
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作者 Zenghua Wang Bing Cai +2 位作者 Deyu Xin Min Zhang Xiaojia Zheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第10期19-29,I0003,共12页
Commercialization of perovskite solar cells(PSCs) requires the development of high-efficiency devices with none current density-voltage(J-V) hysteresis. Here, electron transport layers(ETLs) with gradual change in wor... Commercialization of perovskite solar cells(PSCs) requires the development of high-efficiency devices with none current density-voltage(J-V) hysteresis. Here, electron transport layers(ETLs) with gradual change in work function(WF) are successfully fabricated and employed as an ideal model to investigate the energy barriers, charge transfer and recombination kinetics at ETL/perovskite interface. The energy barrier for electron injection existing at ETL/perovskite is directly assessed by surface photovoltage microscopy, and the results demonstrate the tunable barriers have significant impact on the J-V hysteresis and performance of PSCs. By work function engineering of ETL, PSCs exhibit PCEs over 21% with negligible hysteresis. These results provide a critical understanding of the origin reason for hysteresis effect in planar PSCs, and clear reveal that the J-V hysteresis can be effectively suppressed by carefully tuning the interface features in PSCs. By extending this strategy to a modified formamidinium-cesium-rubidium(FA-Cs-Rb) perovskite system, the PCEs are further boosted to 24.18%. Moreover, 5 cm × 5 cm perovskite mini-modules are also fabricated with an impressive efficiency of 20.07%, demonstrating compatibility and effectiveness of our strategy on upscaled devices. 展开更多
关键词 J-V hysteresis Work function Planar perovskite solar cells Energy barriers Charge transfer kinetics Perovskite solar modules
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A General Algorithm for Biorthogonal Functions and Performance Analysis of Biorthogonal Scramble Modulation System
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作者 Yueyun Chen Zhenhui Tan 《Wireless Sensor Network》 2010年第3期199-205,共7页
Applying the theorems of Mobius inverse and Dirichlet inverse, a general algorithm to obtain biorthogonal functions based on generalized Fourier series analysis is introduced. In the algorithm, the orthogonal function... Applying the theorems of Mobius inverse and Dirichlet inverse, a general algorithm to obtain biorthogonal functions based on generalized Fourier series analysis is introduced. In the algorithm, the orthogonal function can be not only Fourier or Legendre series, but also can be any one of all orthogonal function systems. These kinds of biorthogonal function sets are used as scramble signals to construct biorthogonal scramble modulation (BOSM) wireless transmission systems. In a BOSM system, the transmitted signal has significant security performance. Several different BOSM and orthogonal systems are compared on aspects of BER performance and spectrum efficiency, simulation results show that the BOSM systems based on Chebyshev polynomial and Legendre polynomial are better than BOSM system based on Fourier series, also better than orthogonal MCM and OFDM systems. 展开更多
关键词 BIORTHOGONAL functionS BIORTHOGONAL SCRAMBLE modulation Generalized FOURIER Series MOBIUS INVERSE Wireless Transmission
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A TECHNIQUE FOR MEASURING THE LINEARITY OF A LINEARLY FREQUENCY-MODULATED SIGNAL
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作者 宋景唯 《Journal of Electronics(China)》 1995年第1期66-72,共7页
A technique for measuring the linearity of a linearly frequency-modulated continuous wave (LFM-CW) signal is presented. It uses a delay-line and a mixer to sense the slope of the output of a sweep oscillator, so that ... A technique for measuring the linearity of a linearly frequency-modulated continuous wave (LFM-CW) signal is presented. It uses a delay-line and a mixer to sense the slope of the output of a sweep oscillator, so that the original form of frequency function deviated from idealized linear slope is retrieved by means of spectrum analysis. Consequently,the linearity of the LFM signal is determined. The formulation is performed based on the principle that an angle-modulated signal can be approximated by an amplitude-modulated signal if the modulation coefficient is sufficiently small. To examine the validity of the procedure and to study the effect of each parameter on the accuracy of measurement, a number of computer simulations has been made. The results of simulation show that the error of the measurement is less than 2%. 展开更多
关键词 LINEARITY LINEARLY frequency-modulated CONTINUOUS WAVE FREQUENCY deviation function
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Microbiota treatment of functional constipation:Current status and future prospects
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作者 Yan Li Xiao-Han Zhang Zi-Kai Wang 《World Journal of Hepatology》 2024年第5期776-783,共8页
Functional constipation(FC)is a common disorder that is characterized by diffi-cult stool passage,infrequent bowel movement,or both.FC is highly prevalent,recurs often,accompanies severe diseases,and affects quality o... Functional constipation(FC)is a common disorder that is characterized by diffi-cult stool passage,infrequent bowel movement,or both.FC is highly prevalent,recurs often,accompanies severe diseases,and affects quality of life;therefore,safe and effective therapy with long-term benefits is urgently needed.Microbiota treatment has potential value for FC treatment.Microbiota treatments include modulators such as probiotics,prebiotics,synbiotics,postbiotics,and fecal micro-biota transplantation(FMT).Some probiotics and prebiotics have been adopted,and the efficacy of other microbiota modulators is being explored.FMT is con-sidered an emerging field because of its curative effects;nevertheless,substantial work must be performed before clinical implementation. 展开更多
关键词 functional constipation Gut microbiota Microbiota modulators Fecal microbiota transplantation DYSBIOSIS
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Information System Construction and Function Module Design Based on Reverse Logistics
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作者 赵佳妮 石丽娜 《Journal of Donghua University(English Edition)》 EI CAS 2015年第2期328-331,共4页
Reverse logistics are playing more and more important role with the development of competition and the social responsibility of enterprises.It could be divided into commission acceptance,recycling and returned goods h... Reverse logistics are playing more and more important role with the development of competition and the social responsibility of enterprises.It could be divided into commission acceptance,recycling and returned goods handling.Reverse logistics information system consists of the database establishment,network structure and logic structure design.The collection,storage,processing,transmission and output functions of the reverse logistics information system were discussed in the thesis.Eventually,it established seven modules for the reverse logistics information system including the system management module,oriented module,returning goods processing module,reverse transportation management module,information sharing module,statistical analysis module and cost control module. 展开更多
关键词 logistics responsibility goods commission competition acceptance recycling module collection customers
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EFFICIENT DESIGN METHOD OF COSINE-MODULATED QMF BANKS SATISFYING PR PROPERTY
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作者 Tan Ying He Zhenya(Department of Radio Engineering, Southeast University, Nanjing 210096) 《Journal of Electronics(China)》 1999年第1期51-57,共7页
In this paper the design problem of perfect-reconstruction cosine-modulated QMF banks has been formulated as a quadratic-constrained least-squares (QCLS) minimization problem in which all constrained matrices of the Q... In this paper the design problem of perfect-reconstruction cosine-modulated QMF banks has been formulated as a quadratic-constrained least-squares (QCLS) minimization problem in which all constrained matrices of the QCLS optimization problem are symmetric and positive definite. A cost function which is a convex function of desired prototype filter coefficients is constructed so that this kind of QCLS optimization problems can be efficiently solved. So a global minimizer of this problem can be easily obtained. Results of two design examples are presented to support the derivations and analyses. 展开更多
关键词 Quadratic-constrained least-squares(QCLS) Cosine-modulated QMF BANKS Global optimization Penalty function searching (PS) approach
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DIGITAL PWM OF AC-AC MATRIX CONVERTER BASED ON OUTPUT-VOLTAGE ERROR FUNCTION 被引量:1
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作者 葛红娟 穆新华 +1 位作者 张绍 周波 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第4期307-311,共5页
Based on the output-voltage error function, a novel time discrete modulation technique is proposed for matrix converters (MCs) and time-discrete difference equations of a MC circuit are derived. Switch states of MC ... Based on the output-voltage error function, a novel time discrete modulation technique is proposed for matrix converters (MCs) and time-discrete difference equations of a MC circuit are derived. Switch states of MC are obtained when the output voltage error function is minimized, thus the optimum combination of switch states is derived for the closed-loop control of MC. Meanwhile, advantages of the least calculation workload, the simple process, and the convenient for implementation are brought while switch states are described as space vectors in the α-β coordination system. Simulation and experimental results demonstrate the validity of the time-discrete modulation technique and the feasibility of the control approach. 展开更多
关键词 matrix converter time-discrete modulation error function switch state
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基于S-Function的PWM控制系统仿真 被引量:10
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作者 郝继飞 邢青青 张琳 《电力自动化设备》 EI CSCD 北大核心 2007年第1期50-52,共3页
脉宽调制(PWM)控制方法用于过程控制领域时,由于通过三角波构造PWM控制器不够准确,且三角波参数设置较为复杂,因此提出了利用S函数描述PWM控制算法,通过M文件编写的S函数完全是算法的再现,且生成的S函数模块如Simulink标准模块。结合Mat... 脉宽调制(PWM)控制方法用于过程控制领域时,由于通过三角波构造PWM控制器不够准确,且三角波参数设置较为复杂,因此提出了利用S函数描述PWM控制算法,通过M文件编写的S函数完全是算法的再现,且生成的S函数模块如Simulink标准模块。结合Matlab中的Simulink工具箱对PWM控制系统进行建模,并针对一个一阶系统进行仿真。通过比较说明,用S函数实现的PWM控制器有着准确性高、建模简单等优点。 展开更多
关键词 S-function PWM控制 仿真
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