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From Differential Mode of Association to Tianxia Worldview:A Study on Chinese Entrepreneurial Spirit
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作者 Chao Gang Qian Chen Wang Lei 《China Economist》 2024年第4期58-88,共31页
China has made significant strides in economic and social development since reform and opening up over the past four decades.This process has been influenced by the exceptional innovation and entrepreneurship of Chine... China has made significant strides in economic and social development since reform and opening up over the past four decades.This process has been influenced by the exceptional innovation and entrepreneurship of Chinese business leaders,as well as their profound sentiments of compassion for the world and their country.It is of great significance to foster and promote an entrepreneurial spirit with distinctive Chinese characteristics.Not only is such spirit essential to the high-quality development of enterprises and the economy,but it is also a critical impetus for achieving Chinese modernization.Nevertheless,there is still a paucity of adequate theoretical discourse on the cultural origins and entrepreneurial spirit of outstanding Chinese business leaders.This paper employs the classical grounded theory method to conduct a 10-year follow-up research on 11 representative entrepreneurs and their enterprises.The results indicate that these entrepreneurs exhibit an evolving worldview along the paths of“self-cultivation and moral conduct”,“assisting employees to achieve”,“multilateral symbiosis”,and“the oneness of existence”when interacting with themselves,employees,partners,the general public,and all things in nature.Such entrepreneurial spirit is embodied in this paper as the“Tianxia(all-under-heaven)worldview”.Through theoretical construction,this study defines the concept of“Tianxia worldview”and extensively examines the distinctions and connections between the broadminded“Tianxia worldview”and the kinship-centered“differential mode of association”in terms of internal structure,value orientation,and applicable groups.It is posited that the transition from the former to the latter is a continuous process of transcendence and evolution of the individual mindset.This study has theoretical significance in the context of advancing the research on the Chinese entrepreneurial spirit,transcending the constraints of the management approach based on the“differential mode of association”,and enhancing the research on social responsibility from the perspective of“benefit corporations”.It also has practical value in overcoming the trust dilemma and development impediment of family businesses,ensuring that enterprises consciously fulfill their social responsibilities in a broader social context,and achieving common prosperity and progress for both enterprises and society. 展开更多
关键词 Tianxia worldview differential mode of association Chinese entrepreneurial spirit corporate social responsibility grounded theory method
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How Group Leaders Build Stable Community Buying Groups:A Perspective Based on the Differential Mode of Association
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作者 SI Xiang 《Psychology Research》 2024年第1期30-35,共6页
Since 2016,community group buying has grown significantly in China,largely driven by its efficient logistics,supply chains,low prices,and convenience.This model has been further popularized during the COVID-19 pandemi... Since 2016,community group buying has grown significantly in China,largely driven by its efficient logistics,supply chains,low prices,and convenience.This model has been further popularized during the COVID-19 pandemic due to its effectiveness in meeting daily needs while minimizing human-to-human contact.A key component of this business model is the“group leaders”-influential individuals within a community responsible for managing group buying activities,which include order collection,supplier liaison,and goods distribution.Their primary task is to form and sustain a reliable community group buying consortium,a task that demands excellent organizational and interpersonal skills.This paper examines this phenomenon using the lens of the differential mode of association,a theoretical model explaining interpersonal relationships in traditional Chinese society.The research indicates that group leaders,through regular interaction with consumers,are able to alter their social network position,increase their influence,understand consumer needs,provide satisfying services,and enhance trust,thereby transforming consumers into loyal group buying participants.This transformation not only brings stability to group buying activities but also reinforces the community influence of group leaders,thus fostering the growth of community group buying. 展开更多
关键词 Community group buying China Group leaders The differential mode of association
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Gradient Differentiation and Exploitation Mode of Tourist Resources in Hailuogou Scenic Area,China
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作者 马晓路 许霞 《Journal of Landscape Research》 2011年第3期68-71,共4页
Natural environment of Hailuogou Scenic Area(Conch Gully)was introduced,and it was pointed out that tourist resources in the study area showed gradient differentiation along the vertical height.In view of such gradien... Natural environment of Hailuogou Scenic Area(Conch Gully)was introduced,and it was pointed out that tourist resources in the study area showed gradient differentiation along the vertical height.In view of such gradient differentiation,resource contents and characteristics of its cultural heritages zone,geothermal resources zone,forest vegetation zone,and glacial resources zone were respectively analyzed.Based on the gradient differentiation of tourist resources in Hailuogou Scenic Area,suggestions were given for its further tourism development,and it was stressed that brand effects of the attractions should be enhanced,infrastructure construction and maintenance of newly-explored scenic spots should be improved,and more efforts should be devoted to explore disastrous landform resources.This research is of practical significance for studying spatial differentiation and evolution mechanism of tourist resources in mountainous areas in western China,and also provides scientific support for the exploration of tourist resources in mountainous areas. 展开更多
关键词 TOURISM RESOURCES GRADIENT differentiATION EXPLOITATION mode Hailuogou
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A Simplified Sliding Mode Controlled Electronic Differential for an Electric Vehicle with Two Independent Wheel Drives 被引量:7
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作者 Azeddine Draou 《Energy and Power Engineering》 2013年第6期416-421,共6页
This paper presents a simple sliding mode control strategy used for an electronic differential system for electric vehicle with two independent wheel drives. When a vehicle drives along a curved road lane, the speed o... This paper presents a simple sliding mode control strategy used for an electronic differential system for electric vehicle with two independent wheel drives. When a vehicle drives along a curved road lane, the speed of the inner wheel has to be different from that of the outer wheel in order to prevent the vehicle from vibrating and travelling an unsteady path. Because each wheel of this electrical vehicle has independent driving force, an electrical differential system is required to replace a gear differential system. However, it is difficult to analyse the nonlinear behaviour of the differential system in relation to the speed and steering angle, as well as vehicle structure. The proposed propulsion system consists of two permanent magnet synchronous machines that ensure the drive of the two back driving wheels. The proposed control structure called independent machines for speed control allows the achievement of an electronic differential which ensures the control of the vehicle behaviour on the road. It also allows to control, independently, every driving wheel to turn at different speeds in any curve. Analysis and simulation results of the proposed system are presented in this paper. 展开更多
关键词 Electric Vehicle SLIDING mode Control Electronic differential PERMANENT MAGNET SYNCHRONOUS Motor Multimachine Multiconverter System
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Sliding Mode Control for Fractional Differential Systems with State-delay 被引量:5
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作者 SI Jia-fang JIANG Wei 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第1期117-122,共6页
The problem of sliding mode control for fractional differential systems with statedelay is considered.A novel sliding surface is proposed and a controller is designed correspondingly,such that the state starting from ... The problem of sliding mode control for fractional differential systems with statedelay is considered.A novel sliding surface is proposed and a controller is designed correspondingly,such that the state starting from any initial value will move toward the switching surface and reach the sliding surface in finite time and the state variables on the sliding surface will converge to equilibrium point.And the stability of the proposed control design is discussed. 展开更多
关键词 sliding mode control fractional differential system TIME-DELAY
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Five New MVL Current Mode Differential Absolute Value Circuits Based on Carbon Nano-tube Field Effect Transistors(CNTFETs) 被引量:2
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作者 Mojtaba Jamalizadeh Fazel Sharifi +2 位作者 Mohammad Hossein Moaiyeri Keivan Navi Omid Hashemipour 《Nano-Micro Letters》 SCIE EI CAS 2010年第4期227-234,共8页
Carbon Nano-Tube Field Effect Transistors(CNTFETs) are being widely studied as possible successors to silicon MOSFETs.Using current mode has many advantages such as performing sum operation by means of a simple wired ... Carbon Nano-Tube Field Effect Transistors(CNTFETs) are being widely studied as possible successors to silicon MOSFETs.Using current mode has many advantages such as performing sum operation by means of a simple wired connection.Also,direction of the current can be used to exhibit the sign of digits.It is expected that the advantages of current mode approaches will become even more important with increased speed requirements and decreased supply voltage.In this paper,we present five new circuit designs for differential absolute value in current mode logic which have been simulated by CNTFET model.The considered base current for this model is 2 μA and supply voltage is 0.9 V.In all of our designs we used N-type CNTFET current mirrors which operate as truncated difference circuits.The operation of Differential Absolute Value circuit calculates the difference between two input currents and our circuit designs are operate in 8 logic levels. 展开更多
关键词 CNTFET Current mode Truncated difference differential absolute value
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Use of Double Differential-mode Current Injection Method Equivalent to High Level Illumination for Susceptibility Testing 被引量:3
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作者 LU Xinfu WEI Guanghui PAN Xiaodong 《高电压技术》 EI CAS CSCD 北大核心 2013年第10期2431-2437,共7页
To achieve the electric field strength and the induced currents in equivalence in susceptibility tests with the high-level field radiation above 400 MHz,a double differential-mode(DM) current injection method based on... To achieve the electric field strength and the induced currents in equivalence in susceptibility tests with the high-level field radiation above 400 MHz,a double differential-mode(DM) current injection method based on directional couplers is proposed.Two cascaded symmetrical directional couplers compose a coupling device to inject the DM currents.When the coupling device is used,two devices are necessary to achieve the equivalence between radiation and injection,i.e.the equivalence between the injected voltages and the field strength,which is linear,regardless of the characteristics of the equipment under test(EUT).The results are verified by experiments using typical coaxial cables and nonlinear devices,where the equivalence between the nonlinear EUT responses induced by radiation and injection at both ends is achieved by using two coupling devices.At a frequency up to 1.75 GHz,the maximal experimental error is only 3.39%.The experimental results confirm the accuracy of the proposed method even both the EUTs work in the nonlinear region.The proposed method is applicable for radiated susceptibility(RS) testing of interconnected systems in the microwave frequency band. 展开更多
关键词 电流注入法 药敏试验 差模 定向耦合器 非线性器件 照明 实验误差 电场强度
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Adaptive Differentiators via Second Order Sliding Mode for a Fixed Wing Aircraft
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作者 M.Zaouche A.Beloula +2 位作者 R.Louali S.Bouaziz M.Hamerlain 《Computer Modeling in Engineering & Sciences》 SCIE EI 2015年第3期159-184,共26页
Safety automation of complex mobile systems is a current topic issue in industry and research laboratories,especially in aeronautics.The dynamic models of these systems are nonlinear,Multi-Input Multi-Output(MIMO)and ... Safety automation of complex mobile systems is a current topic issue in industry and research laboratories,especially in aeronautics.The dynamic models of these systems are nonlinear,Multi-Input Multi-Output(MIMO)and tightly coupled.The nonlinearity resides in the dynamic equations and also in the aerodynamic coefficients’variability.This paper is devoted to developing the piloting law based on the combination of the robust differentiator with a dynamic adaptation of the gains and the robust controller via second order sliding mode,by using an aircraft in virtual simulated environments.To deal with the design of an autopilot controller,we propose an environment framework based on a Software In the Loop(SIL)methodology and we use Microsoft Flight Simulator(FS-2004)as the environment for plane simulation.The first order sliding mode control may be an appropriate solution to this piloting problem.However,its implementation generates a chattering phenomenon and a singularity problem.To overcome these problems,a new version of the adaptive differentiators for second order sliding modes is proposed and used for piloting.For the sliding mode algorithm,higher gains values may be used to improve accuracy;however this leads to an amplification of noise in the estimated signals.A good tradeoff between these two criteria(accuracy,robustness to noise ratio)is difficult to achieve.On the one hand,these values must increase the gains in order to derive a signal sweeping of some frequency ranges.On the other hand,low gains values have to be imposed to reduce noise amplification.So,our goal is to develop a differentiation algorithm in order to have a good compromise between error and robustness to noise ratio.To fit this requirement,a new version of differentiators with a higher order sliding modes and a dynamic adaptation of the gains,is proposed:the first order differentiator for the control of longitudinal speed and the second order differentiator for the control of the Euler angles. 展开更多
关键词 ADAPTIVE differentiators second order SLIDING modeS Dynamic adaptation of the GAINS Microsoft FLIGHT Simulator
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Voltage-Mode Universal Biquad Filter Employing Single Voltage Differencing Differential Input Buffered Amplifier 被引量:2
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作者 Kanhaiya Lal Pushkar Data Ram Bhaskar Dinesh Prasad 《Circuits and Systems》 2013年第1期44-48,共5页
A new multi function voltage-mode universal biquadratic filter using single Voltage Differencing Differential Input Buffered Amplifier (VD-DIBA), two capacitors and one resistor is proposed. The proposed configuration... A new multi function voltage-mode universal biquadratic filter using single Voltage Differencing Differential Input Buffered Amplifier (VD-DIBA), two capacitors and one resistor is proposed. The proposed configuration has four inputs and one output and can realize all the five standard filters from the same circuit configuration. The presented biquad filter offers low active and passive sensitivities. The validity of proposed universal biquadratic filter has been verified by SPICE simulation using 0.35 μm MIETEC technology. 展开更多
关键词 VOLTAGE Differencing differential INPUT Buffered AMPLIFIER ANALOG Filter VOLTAGE-mode
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Research on the Equivalence Between Double Differential- mode Current Injection and Radiation Test Method 被引量:1
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作者 PAN Xiaodong WEI Guanghui +2 位作者 FAN Lisi LU Xinfu YANG Zhe 《高电压技术》 EI CAS CSCD 北大核心 2013年第8期2031-2037,共7页
There are the application scope limits for single differential-mode current injection test method, so in order to carry out injection susceptibility test for two-pieces equipment interconnected with both ends of a cab... There are the application scope limits for single differential-mode current injection test method, so in order to carry out injection susceptibility test for two-pieces equipment interconnected with both ends of a cable simultaneously, a double differential-mode current in- jection test method (DDMCI) is proposed. The method adopted the equivalence source wave theorem and Baum-Liu-Tesche(BLT) equation as its theory foundation. The equivalent corresponding relation between injection voltage and radiation electric field intensity is derived, and the phase relation between the two injection voltage sources is confirmed. The results indicate that the amplitude and phase of the equivalent injection voltage source is closely related to the S parameter of directional coupling device, the transmission line length, and the source vector in BLT equation, but has nothing to do with the reflection coefficient between the two equipment pieces. Therefore, by choosing the right amplitude and phase of the double injection voltage sources, the DDMCI test is equivalent to the radiation test for two interconnected equipment of a system. 展开更多
关键词 测试方法 差模电流 辐射测试 电流注入 等价 BLT方程 相位关系 敏感性试验
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Current Mode Universal Filter Using Single Current Controlled Differential Difference Current Conveyor Transconductance Amplifier
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作者 Ajay Kumar Kushwaha Sajal K. Paul 《Circuits and Systems》 2015年第10期224-236,共13页
This research paper contains a new electronically tunable current-mode biquadratic universal filter using a new active building block;current controlled differential difference current conveyor transconductance amplif... This research paper contains a new electronically tunable current-mode biquadratic universal filter using a new active building block;current controlled differential difference current conveyor transconductance amplifier (CCDDCCTA). The proposed filter provides the following important and desirable features: (i) One can use only one CCDDCCTA and two capacitors;(ii) One can get low pass (LP), band pass (BP), high pass (HP), notch (NF) and all pass (AP) current responses from the same configuration without any alteration;(iii) Passive components are grounded, which ease the integrated circuit implementation;(iv) Responses are electronically tunable;and (v) Sensitivity is low. Moreover, the non-ideality analysis shows that the parasitic passive components can be compensated for the proposed circuit. The functionality of the design is verified through SPICE simulations using 0.25 μm CMOS TSMC technology process parameters. Simulation result agrees well with the theoretical analysis. 展开更多
关键词 CURRENT mode Analog FILTER Universal FILTER CURRENT Controlled differentiAL DIFFERENCE CURRENT CONVEYOR TRANSCONDUCTANCE Amplifier (CCDDCCTA) Monte-Carlo Analysis
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K-Modes聚类数据收集和发布过程中的混洗差分隐私保护方法 被引量:1
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作者 蒋伟进 陈艺琳 +3 位作者 韩裕清 吴玉庭 周为 王海娟 《通信学报》 EI CSCD 北大核心 2024年第1期201-213,共13页
针对目前聚类数据收集与发布安全性不足的问题,为保护聚类数据中的用户隐私并提高数据质量,基于混洗差分隐私模型,提出一种去可信第三方的K-Modes聚类数据收集和发布的隐私保护方法。首先,使用K-Modes聚类数据收集算法对用户数据进行采... 针对目前聚类数据收集与发布安全性不足的问题,为保护聚类数据中的用户隐私并提高数据质量,基于混洗差分隐私模型,提出一种去可信第三方的K-Modes聚类数据收集和发布的隐私保护方法。首先,使用K-Modes聚类数据收集算法对用户数据进行采样并加噪,再通过填补取值域随机排列发布算法打乱采样数据的初始顺序,使恶意攻击者不能根据用户与数据之间的关系识别出目标用户。然后,尽可能减小噪声的干扰,利用循环迭代的方式计算出新的质心完成聚类。最后,从理论层面上分析了以上3种方法的隐私性、可行性和复杂度,并利用3个真实数据集和近年来具有权威性的同类算法KM、DPLM、LDPKM等进行准确率、熵值的对比,验证所提方法的有效性。实验结果表明,所提方法的隐私保护和发布数据质量均优于当前同类算法。 展开更多
关键词 混洗差分隐私 K-modes聚类 隐私保护 数据收集 数据发布
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基于k-modes聚类算法的混洗差分隐私方法
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作者 祁富 陈丽敏 《牡丹江师范学院学报(自然科学版)》 2024年第2期6-13,共8页
首次提出一种基于k-modes聚类算法的混洗差分隐私保护方案(简称SDPk-modes).SDPk-modes根据每个数据之间的距离划分为不同的组,得到足够的细粒度优化效用,采用基于梯度随机扰动技术使计算最优概率耗时更短;在k-modes聚类过程中,通过将... 首次提出一种基于k-modes聚类算法的混洗差分隐私保护方案(简称SDPk-modes).SDPk-modes根据每个数据之间的距离划分为不同的组,得到足够的细粒度优化效用,采用基于梯度随机扰动技术使计算最优概率耗时更短;在k-modes聚类过程中,通过将数据中频繁出现的特征向量作为聚类中心点,基于属性熵的距离度量方法,加快算法收敛至聚类中心的速度,解决原始算法聚类速度慢、易陷入局部最优等问题,显著提高聚类的效果.实验验证表明,本文提出的方案优于当前同类方案. 展开更多
关键词 混洗差分隐私 k-modes 随机响应机制 隐私保护
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基于本地差分隐私的K-modes聚类数据隐私保护方法 被引量:8
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作者 张少波 原刘杰 +1 位作者 毛新军 朱更明 《电子学报》 EI CAS CSCD 北大核心 2022年第9期2181-2188,共8页
分类型数据聚类是数据挖掘的重要研究内容,聚类数据中通常包含用户一些敏感信息.为保护聚类数据中的用户隐私,当前主要采用基于可信第三方隐私保护模型,但现实中第三方也存在隐私泄露风险.针对此问题,该文引入本地差分隐私技术,提出一... 分类型数据聚类是数据挖掘的重要研究内容,聚类数据中通常包含用户一些敏感信息.为保护聚类数据中的用户隐私,当前主要采用基于可信第三方隐私保护模型,但现实中第三方也存在隐私泄露风险.针对此问题,该文引入本地差分隐私技术,提出一种去可信第三方的K-modes聚类数据隐私保护方法.该方法首先利用随机采样技术对数据进行采样,然后使用本地差分隐私技术对采样数据进行扰动,最后通过聚类服务端与用户的交互迭代完成聚类.在聚类过程中,无需可信第三方对数据进行隐私预处理,避免了第三方泄露用户隐私的风险.理论分析证明了该方法的隐私性和可行性,实验结果表明该方法在满足本地差分隐私机制的前提下保证了聚类结果的质量. 展开更多
关键词 隐私保护 本地差分隐私 数据挖掘 K-modes聚类 去可信第三方
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Non-Negative Adaptive Mechanism-Based Sliding Mode Control for Parallel Manipulators with Uncertainties 被引量:1
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作者 Van-Truong Nguyen 《Computers, Materials & Continua》 SCIE EI 2023年第2期2771-2787,共17页
In this paper,a non-negative adaptive mechanism based on an adaptive nonsingular fast terminal sliding mode control strategy is proposed to have finite time and high-speed trajectory tracking for parallel manipulators... In this paper,a non-negative adaptive mechanism based on an adaptive nonsingular fast terminal sliding mode control strategy is proposed to have finite time and high-speed trajectory tracking for parallel manipulators with the existence of unknown bounded complex uncertainties and external disturbances.The proposed approach is a hybrid scheme of the online non-negative adaptive mechanism,tracking differentiator,and nonsingular fast terminal sliding mode control(NFTSMC).Based on the online non-negative adaptive mechanism,the proposed control can remove the assumption that the uncertainties and disturbances must be bounded for the NFTSMC controllers.The proposed controller has several advantages such as simple structure,easy implementation,rapid response,chattering-free,high precision,robustness,singularity avoidance,and finite-time convergence.Since all control parameters are online updated via tracking differentiator and non-negative adaptive law,the tracking control performance at high-speed motions can be better in real-time requirement and disturbance rejection ability.Finally,simulation results validate the effectiveness of the proposed method. 展开更多
关键词 Parallel manipulator uncertainties and disturbances nonsingular fast terminal sliding mode control non-negative adaptive mechanism tracking differentiator
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支持本地化差分隐私保护的k-modes聚类方法 被引量:12
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作者 彭春春 陈燕俐 荀艳梅 《计算机科学》 CSCD 北大核心 2021年第2期105-113,共9页
如何在保护数据隐私的同时进行可用性的数据挖掘已成为热点问题。鉴于在很多实际应用场景中,很难找到一个真正可信的第三方对用户的敏感数据进行处理,文中首次提出了一种支持本地化差分隐私技术的聚类方案——LDPK-modes(Local Differen... 如何在保护数据隐私的同时进行可用性的数据挖掘已成为热点问题。鉴于在很多实际应用场景中,很难找到一个真正可信的第三方对用户的敏感数据进行处理,文中首次提出了一种支持本地化差分隐私技术的聚类方案——LDPK-modes(Local Differential Privacy K-modes)。与传统的基于中心化差分隐私的聚类算法相比,其不再需要一个可信的第三方对数据进行收集和处理,而由用户担任数据隐私化的工作,极大地降低了第三方窃取用户隐私的可能性。用户使用满足本地d-隐私(带有距离度量的本地差分隐私技术)定义的随机响应机制对敏感数据进行扰动,第三方收集到用户扰动数据后,恢复其统计特征,生成合成数据集,并进行k-modes聚类。在聚类过程中,将数据集上频繁出现的特征分配给初始聚类中心点,进一步提高了聚类结果的可用性。理论分析和实验结果表明了LDPK-modes的隐私性和聚类可用性。 展开更多
关键词 本地化差分隐私 k-modes d-隐私 聚类 隐私保护
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Chiral asymmetry of anti-symmetric coordinates studied by the Raman differential bond polarizability of S-phenylethylamine
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作者 沈红霞 吴国祯 王培杰 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第12期191-197,共7页
The Raman optical activity (ROA) study on S-phenylethylamine is presented by the intensity analyses via bond polarizability and differential bond polarizability. Ample information concerning the physical picture of ... The Raman optical activity (ROA) study on S-phenylethylamine is presented by the intensity analyses via bond polarizability and differential bond polarizability. Ample information concerning the physical picture of this chiral system is obtained, and its ROA mechanism is constructed. Especially, we propose that the asymmetric modes and/or the off-diagonal elements of the electronic polarizability tensor are the potential keys to the exploration of ROA. 展开更多
关键词 Raman optical activity intensity study asymmetric modes differential bond polariz-ability S-phenylethylamine
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Sliding-mode observers for systems with unknown inputs and measurement disturbances 被引量:1
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作者 韩冬 李春茹 《Journal of Chongqing University》 CAS 2015年第2期63-72,共10页
The method to design sliding-mode observers for systems with unknown inputs and measurement disturbances is presented in the paper. An augmented system is constructed by viewing the measurement disturbances as unknow ... The method to design sliding-mode observers for systems with unknown inputs and measurement disturbances is presented in the paper. An augmented system is constructed by viewing the measurement disturbances as unknow inputs. For such an augmented system, the so-called observer matching condition is not satisfied. Based on the construction of auxiliary outputs, the observer matching condition may be satisfied. High-order sliding-mode differentiators are developed to obtain the estimates of those unmeasurable variables contained in the auxiliary output vector. Employing the estimate of auxiliary output vector, a sliding-mode observer is designed. The simulation results to a real model show that the proposed method is effective. 展开更多
关键词 augmented system high-order sliding-mode differentiators measurement disturbances sliding-mode observer
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Buck Converter Current Measurement Using Differential Amplifier
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作者 P.Rajeswari V.Manikandan 《Intelligent Automation & Soft Computing》 SCIE 2023年第2期1387-1402,共16页
The accuracy of the measured current is a preeminent parameter for Current Control based Power Converter applications to ensure genuine operation of the designed converter.The current measurement accuracy can be affec... The accuracy of the measured current is a preeminent parameter for Current Control based Power Converter applications to ensure genuine operation of the designed converter.The current measurement accuracy can be affected by several parameters which includes the type of technology used,components used for the selected technology,aging,usage,operating and environmental conditions.The effect of gain resistors and their manufacturing tolerances on differential amplifier-based buck converter current measurement is investigated in this work.The analysis mainly focused on the output voltage variation and its accuracy with respect to the change in gain resistance tolerances.The gain resistors with 5%,1%,0.5%and 0.1%manufacturing tolerances taken for the worst-case analysis and the calculated performance results are compared and verified with the simula-tion results.The Operational amplifiers(Op-Amp)for high frequency power con-verter applications must operate in a high frequency noise environment and the intended current measuring system must manage common mode noise distur-bances paired with the signal to be measured.Based on the Common Mode Rejec-tion Ratio(CMRR)the common mode voltages and noise signals will effectively getfiltered out.Lesser CMRR results in lower common mode signal rejection,resulting in poor precision and noise rejection.In differential amplifiers,the CMRR predominantly depends on gain resistors.So,the variations in Common Mode Rejection Ratio due to gain resistor tolerances also analyzed and compared with the output voltage variations.Besides the effects of resistor tolerances,this paper also examines the effect of Op-Amp offset voltage on output accuracy spe-cifically for low magnitude input currents.The obtained results from this analysis clearly shows that the gain resistors with 0.1%tolerance gives maximum accuracy with improved CMRR and accuracy at low magnitude input currents will get well improved by using Op-Amps with Low Offset voltage specifications. 展开更多
关键词 Buck converter common mode rejection ratio common mode gain current sensing differential amplifier differential mode gain shunt resistor
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Water Gauge Image Denoising Model Based on Improved Adaptive Total Variation 被引量:1
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作者 SHI Zhenting ZHOU Xianchun +2 位作者 ZHANG Ying LI Ting LU Siqi 《Instrumentation》 2023年第1期59-68,共10页
As an important part of water level warning in water conservancy projects,often due to the influence of environmental factors such as light and stains,the acquired water gauge images have sticky,broken and bright spot... As an important part of water level warning in water conservancy projects,often due to the influence of environmental factors such as light and stains,the acquired water gauge images have sticky,broken and bright spot conditions,which affect the identification of water gauges.To solve this problem,a water gauge image denoising model based on improved adaptive total variation is proposed.Firstly,the regular term exponent in the adaptive total variational equation is changed to an inverse cosine function;secondly,the differential curvature is used to distinguish the image noise points and increase the smoothing strength at the noise points;finally,according to the characteristics of the gradient mode and adaptive gradient threshold after Gaussian filtering,the New model can adaptively denoise in the smooth area and protect the edge area,so as to have the characteristics of both edge-preserving denoising.The experimental results show that the new model has a great improvement in image vision,higher iteration efficiency and an average increase of 1.6 dB in peak signal-to-noise ratio,and an average increase of 9%in structural similarity,which is more beneficial to practical applications. 展开更多
关键词 Water Gauge Image Adaptive Total Variation differential Curvature Gradient mode Adaptive Gradient Threshold
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