Digital transformation provides enterprises with new development momenta.Understanding the relationship between digital transformation and total factor productivity(TFP)is essential.This study employs a fixedeffect mo...Digital transformation provides enterprises with new development momenta.Understanding the relationship between digital transformation and total factor productivity(TFP)is essential.This study employs a fixedeffect model and selects all Chinese A-share listed companies from 2007 to 2022 as the research sample.Internal control(IC)is introduced as a mechanistic variable.The results indicate that digital transformation significantly promotes both TFP and the effectiveness of IC.Moreover,effective IC plays a significant mediating role in the relationship between digital transformation and TFP.A heterogeneity analysis reveals that,compared to non-state-owned enterprises,state-owned enterprises can improve TFP more rapidly through digital transformation due to their resource advantages and policy support.On the one hand,these findings help enterprises better align their transformation strategies to maximize the benefits of digital transformation.On the other hand,they provide investors with insights into the transformation potential and future growth prospects of these enterprises.展开更多
Under the background of increasingly complex global economic development and financial markets,the legal risks faced by enterprises are increasingly intensified.As an important legal norm to adjust financial activitie...Under the background of increasingly complex global economic development and financial markets,the legal risks faced by enterprises are increasingly intensified.As an important legal norm to adjust financial activities,financial law has put forward higher requirements for the operation and risk management of enterprises.Therefore,the article will start from the concept of internal legal risk prevention and control under the financial perspective,study and analyze the common internal legal risks and the causes of risks,and put forward the specific measures of prevention and control of internal legal risks.展开更多
With the development of modern society,the functions of administrative institutions and public institutions are constantly evolving.Under the background of comprehensively deepening reform,higher requirements are put ...With the development of modern society,the functions of administrative institutions and public institutions are constantly evolving.Under the background of comprehensively deepening reform,higher requirements are put forward for the financial management of administrative institutions and public institutions.The financial management status of administrative institutions and public institutions will directly affect the quality of public services.Therefore,it is necessary to strengthen the internal control of financial management.By leveraging the constraints and supervision mechanisms of internal control,the transparency and credibility of financial management can be effectively enhanced.However,in the actual internal control and financial management of administrative institutions and public institutions,there are still some problems,which make it difficult to improve the level of financial management and affect the sustainable development of administrative institutions and public institutions.By analyzing the internal control and financial management of administrative institutions and public institutions under the new situation,this article proposes plans such as strengthening the construction of professional management teams,deeply using information technology means,and improving the internal control system,effectively enhancing the management efficiency of administrative institutions and public institutions and better adapting to the development of the times.展开更多
The propagation form of internal cracks induced by continuous casting soft reduction and the control strategy for enhancing the internal quality of 45 steel through industrial trials and a three-dimensional flow-heat ...The propagation form of internal cracks induced by continuous casting soft reduction and the control strategy for enhancing the internal quality of 45 steel through industrial trials and a three-dimensional flow-heat transfer-solidification coupling model were investigated.The results showed that the internal cracks induced by soft reduction exhibited a characteristic of being"coarse in the middle and fine at both ends",and displayed an elliptical arc distribution on the loose side of the strand cross section.The cracks originated within the brittle temperature range and propagated inward to the liquid impenetrable temperature and outward to the zero ductility temperature or below.The control strategy for enhancing the internal quality of the 45 steel strand through soft reduction is to adjust the casting speed or the reduction zone appropriately,ensuring that the central solid fraction of the reduction zone falls within the range of 0.33-0.99.At this point,a reasonable reduction amount is allocated to eliminate the center shrinkage cavities and center segregation,even if it results in minor reduction-induced cracks.展开更多
Coherent beam combining(CBC) of fiber laser array is a promising technique to realize high output power while maintaining near diffraction-limited beam quality. To implement CBC, an appropriate phase control feedback ...Coherent beam combining(CBC) of fiber laser array is a promising technique to realize high output power while maintaining near diffraction-limited beam quality. To implement CBC, an appropriate phase control feedback structure should be established to realize phase-locking. In this paper, an innovative internal active phase control CBC fiber laser array based on photodetector array is proposed. The dynamic phase noises of the laser amplifiers are compensated before being emitted into free space. And the static phase difference compensation of emitting laser array is realized by interference measurement based on photodetector array. The principle of the technique is illustrated and corresponding simulations are carried out, and a CBC system with four laser channels is built to verify the technique. When the phase controllers are turned on, the phase deviation of the laser array is less than λ/20, and ~ 95% fringe contrast of the irradiation distribution is obtained. The technique proposed in this paper could provide a reference for the system design of a massive high-power CBC system.展开更多
Small and medium-sized enterprises(SMEs)constitute the primary drivers of production within the nation’s existing enterprise landscape.They represent the most dynamic segment of the national economy and play a pivota...Small and medium-sized enterprises(SMEs)constitute the primary drivers of production within the nation’s existing enterprise landscape.They represent the most dynamic segment of the national economy and play a pivotal role in supporting economic growth,fostering employment,and enhancing people’s livelihoods.However,despite their significant and extensive organizational structures,only a fraction of these companies have established internal control systems,and even fewer possess robust ones.Building upon this premise and considering the prevailing circumstances of SMEs,this paper undertakes an empirical analysis of monetary fund management within this sector.It delves into the operational intricacies,exploring how monetary funds should be effectively implemented to ensure their safety and integrity.Furthermore,it proposes viable strategies to enhance the circulation efficiency of monetary funds,thereby maximizing benefits for enterprises.Addressing these challenges is crucial for SME managers striving to achieve sustainable profit growth and navigate the complexities of financial management.展开更多
As an important pillar of national economic development,state-owned enterprises,their operational efficiency,and risk management ability are directly related to the stability and security of the national economy.As an...As an important pillar of national economic development,state-owned enterprises,their operational efficiency,and risk management ability are directly related to the stability and security of the national economy.As an important part of enterprise management,internal control management plays an irreplaceable role.Especially in the current domestic and international economic situation is complex and changeable,market competition is increasingly fierce environment,to strengthen the internal control management of state-owned enterprises and risk prevention measures is particularly important.This paper starts with the importance of internal control management and risk prevention for state-owned enterprises,and analyzes the problems and strategies in the internal control management and risk prevention of state-owned enterprises,in order to build a more comprehensive and efficient risk management system for state-owned enterprises to adapt to the ever-changing market environment and realize sustainable development.展开更多
Fixed assets in universities occupy an important position in university management due to their wide coverage and large amount of money.Due to insufficient funding supply,private universities mainly focus on the alloc...Fixed assets in universities occupy an important position in university management due to their wide coverage and large amount of money.Due to insufficient funding supply,private universities mainly focus on the allocation and utilization of fixed assets,which reflects the overall characteristics of cautious allocation,maximum utilization,and delayed elimination in the actual management of fixed assets.This article aims to conduct research and analysis on the entire lifecycle process of the allocation,use,and disposal of fixed assets in private universities,summarize the problems existing in the internal control of fixed assets in private universities,and propose corresponding countermeasures and suggestions in a targeted manner.展开更多
This paper outlines the internal control management of hospital accounting and finance,introducing its concept,importance,and objectives.It then analyzes the problems existing in the internal control management of hos...This paper outlines the internal control management of hospital accounting and finance,introducing its concept,importance,and objectives.It then analyzes the problems existing in the internal control management of hospital accounting and finance,including an unsound management system,insufficient system implementation,inadequate risk assessment and control capabilities,poor information communication,weak internal supervision,and uneven personnel quality.The reasons for these problems are also analyzed,including outdated management concepts,irrational organizational structures,imperfect training and incentive mechanisms,low levels of information technology,and changes in the external environment.This paper proposes improvement measures for the internal control management of hospital accounting,including enhancing the management system,strengthening system implementation,improving risk assessment and control capabilities,enhancing the information communication mechanism,strengthening internal supervision,improving personnel quality,advancing information technology,and adapting to changes in the external environment.展开更多
The quality system of any modern pharmaceutical company is the pharmaceutical quality system(PQS),which extends the GMP standards to all stages of the medicinal productslife cycle,from pharmaceutical development to it...The quality system of any modern pharmaceutical company is the pharmaceutical quality system(PQS),which extends the GMP standards to all stages of the medicinal productslife cycle,from pharmaceutical development to its withdrawal from production.The principal difference between PQS and GxP rules from other quality systems is that the medicinal product,its safety and efficacy is put at the forefront.At the same time,PQS implies a process approach to all components that should be aimed at achieving the main goal—ensuring and guaranteeing the quality of the medicinal product for the end user(patient)—and should be based on the quality risk management system.An integral part of PQS,as well as the GxP rules adopted in the European Union and PIC/S,is a process for self-inspections and/or quality audits,which regularly appraises the effectiveness and applicability of the PQS.This publication is dedicated to the definition of self-inspections(internal audits)as one of the PQS’s processes.The article defines the main standard stages and develops a model of a risk-based approach to the self-inspections’planning in relation to processes of the pharmaceutical quality system.展开更多
The start-up current control of the high-speed brushless DC（HS-BLDC） motor is a challenging research topic. To effectively control the start-up current of the sensorless HS-BLDC motor, an adaptive control method is ...The start-up current control of the high-speed brushless DC（HS-BLDC） motor is a challenging research topic. To effectively control the start-up current of the sensorless HS-BLDC motor, an adaptive control method is proposed based on the adaptive neural network（ANN）inverse system and the two degrees of freedom（2-DOF） internal model controller（IMC）. The HS-BLDC motor is identified by the online least squares support vector machine（OLS-SVM） algorithm to regulate the ANN inverse controller parameters in real time. A pseudo linear system is developed by introducing the constructed real-time inverse system into the original HS-BLDC motor system. Based on the characteristics of the pseudo linear system, an extra closed-loop feedback control strategy based on the 2-DOF IMC is proposed to improve the transient response performance and enhance the stability of the control system. The simulation and experimental results show that the proposed control method is effective and perfect start-up current tracking performance is achieved.展开更多
A modified two-degrees-of-freedom( M-TDOF) internal model control( IMC) method is proposed for non-square systems with multiple time delays and right-half-plane( RHP) zeros. In this method,pseudo-inverse is introduced...A modified two-degrees-of-freedom( M-TDOF) internal model control( IMC) method is proposed for non-square systems with multiple time delays and right-half-plane( RHP) zeros. In this method,pseudo-inverse is introduced to design the internal model controller,and a desired closed-loop transfer function is designed to eliminate the unrealizable factors of the derived controller. In addition,set-point tracking and load-disturbance rejection of each process are separately controlled by two controllers. The simulation results show that in addition to high decoupling performance and robustness,the proposed control method also effectively improves loaddisturbance rejection and simultaneously optimizes the input tracking performance and disturbance rejection performance by selecting the parameters of controllers. Furthermore,the higher tolerance of model mismatch is achieved in this paper.展开更多
Pyropia haitanensis is an economically important mariculture crop in China and has a high research value for several life phenomena, for example environmental tolerance. To explore the mechanisms underlying these char...Pyropia haitanensis is an economically important mariculture crop in China and has a high research value for several life phenomena, for example environmental tolerance. To explore the mechanisms underlying these characteristics, gene expression has been investigated at the whole transcriptome level. Gene expression studies using quantitative real-time PCR should start by selecting an appropriate internal control gene; therefore, the absolute expression abundance of six housekeeping genes （18S rRNA （18S）, ubiquitin-conju-ating enzyme （UBC）, actin （ACT）, β-tubulin （TUB）, elongation factors 2 （EF2）, and glyceraldehyde-3-phos- phate dehydrogenase （GAPDH） examined by the quantitative real-time PCR in samples corresponding to different strains, life-cycle stages and abiotic stress treatments. Their expression stabilities were assessed by the comparative cycle threshold （Ct） method and by two different software packages： geNorm and NormFinder. The most stable housekeeping gene is UBC and the least stable housekeeping is GADPH. Thus, it is proposed that the most appropriate internal control gene for expression analyses in P. haitanensis is UBC. The results pave the way for further gene expression analyses of different aspects of P. haitanensis biology including different strains, life-history stages and abiotic stress responses.展开更多
Denitrification plays an important role in nitrogen(N) removal in freshwater ecosystems.This internal process regulates the fluctuations of N concentration, especially for lakes with high nutrients concentrations and ...Denitrification plays an important role in nitrogen(N) removal in freshwater ecosystems.This internal process regulates the fluctuations of N concentration, especially for lakes with high nutrients concentrations and long residence time. Lakes in Yunnan plateau(southwestern China) provide typical cases, while studies in this region have been rare.Therefore, we studied denitrification of two lakes(Lake Dianchi in hypereutrophic state and Lake Erhai in mesotrophic) in this region. We used acetylene inhibition technique to quantify potential denitrification rate(PDR) of these lakes in April and August, 2015 and 2016. PDR of the sediments ranged 0–1.21 μmol/(N·m^2·hr), and that of overlying water ranged 0–0.24 μmol/(N·L·hr). Then, we used Least Angle Regression to determine the controlling factors for denitrification. Nutrients controlled PDR from two aspects: providing essential nitrogen sources; and affecting the richness and metabolism of denitrifying bacteria. In April, both aspects limited PDR; while only nitrogen sources limited PDR in August, due to depleted nitrate and enhanced denitrifying bacteria activity. Ammonia was most significant to denitrification, indicating that nitrate from nitrification transported to the bottom of wellmixed lake provide major N source by denitrification. The high PDR and low nitrate concentrate in August were evidence of an enhanced internal N cycling by algal blooms.展开更多
In this paper, an iterative learning control algorithm is proposed for discrete linear time-varying systems to track iterationvarying desired trajectories. A high-order internal model(HOIM) is utilized to describe the...In this paper, an iterative learning control algorithm is proposed for discrete linear time-varying systems to track iterationvarying desired trajectories. A high-order internal model(HOIM) is utilized to describe the variation of desired trajectories in the iteration domain. In the sequel, the HOIM is incorporated into the design of learning gains. The learning convergence in the iteration axis can be guaranteed with rigorous proof. The simulation results with permanent magnet linear motors(PMLM) demonstrate that the proposed HOIM based approach yields good performance and achieves perfect tracking.展开更多
A novel control scheme of active disturbance rejection internal model control(ADRIMC) is proposed to improve the anti-interference ability and robustness for the dead-time process. The active anti-interference concept...A novel control scheme of active disturbance rejection internal model control(ADRIMC) is proposed to improve the anti-interference ability and robustness for the dead-time process. The active anti-interference concept is introduced into the internal model control(IMC) by analyzing the relationship between IMC and disturbance observer control(DOB). Further, a design process of disturbance filter is presented to realize the active anti-interference ability for ADRIMC scheme. The disturbance filter is used to estimate an equivalent disturbance consisting of both external disturbances and internal disturbances caused by model mismatches.Simulation results demonstrate that the proposed method possesses a good disturbance rejection performance, though losing some partial dynamic performance. In other words, the proposed method shows a tradeoff between the dynamic performance and the system robust.展开更多
In this paper,a multi-loop internal model control(IMC) scheme in conjunction with feed-forward strategy based on the dynamic partial least squares(DyPLS) framework is proposed.Unlike the traditional methods to decoupl...In this paper,a multi-loop internal model control(IMC) scheme in conjunction with feed-forward strategy based on the dynamic partial least squares(DyPLS) framework is proposed.Unlike the traditional methods to decouple multi-input multi-output(MIMO) systems,the DyPLS framework automatically decomposes the MIMO process into a multi-loop system in the PLS subspace in the modeling stage.The dynamic filters with identical structure are used to build the dynamic PLS model,which retains the orthogonality among the latent variables.To address the model mismatch problem,an off-line least squares method is applied to obtain a set of optimal filter parameters in each latent space.Without losing the merits of model-based control,a simple and easy-tuned IMC structure is readily carried over to the dynamic PLS control framework.In addition,by projecting the measurable disturbance into the latent subspace,a multi-loop feed-forward control is yielded to achieve better performance for disturbance rejection.Simulation results of a distillation column are used to further demonstrate this new strategy outperforms conventional control schemes in servo behavior and disturbance rejection.展开更多
Because of vehicle＇s external disturbances and model uncertainties,robust control algorithms have obtained popularity in vehicle stability control.The robust control usually gives up performance in order to guarantee...Because of vehicle＇s external disturbances and model uncertainties,robust control algorithms have obtained popularity in vehicle stability control.The robust control usually gives up performance in order to guarantee the robustness of the control algorithm,therefore an improved robust internal model control（IMC） algorithm blending model tracking and internal model control is put forward for active steering system in order to reach high performance of yaw rate tracking with certain robustness.The proposed algorithm inherits the good model tracking ability of the IMC control and guarantees robustness to model uncertainties.In order to separate the design process of model tracking from the robustness design process,the improved 2 degree of freedom（DOF） robust internal model controller structure is given from the standard Youla parameterization.Simulations of double lane change maneuver and those of crosswind disturbances are conducted for evaluating the robust control algorithm,on the basis of a nonlinear vehicle simulation model with a magic tyre model.Results show that the established 2-DOF robust IMC method has better model tracking ability and a guaranteed level of robustness and robust performance,which can enhance the vehicle stability and handling,regardless of variations of the vehicle model parameters and the external crosswind interferences.Contradiction between performance and robustness of active steering control algorithm is solved and higher control performance with certain robustness to model uncertainties is obtained.展开更多
A multi-loop adaptive internal model control (IMC) strategy based on a dynamic partial least squares (PLS) frame-work is proposed to account for plant model errors caused by slow aging,drift in operational conditions,...A multi-loop adaptive internal model control (IMC) strategy based on a dynamic partial least squares (PLS) frame-work is proposed to account for plant model errors caused by slow aging,drift in operational conditions,or environmental changes.Since PLS decomposition structure enables multi-loop controller design within latent spaces,a multivariable adaptive control scheme can be converted easily into several independent univariable control loops in the PLS space.In each latent subspace,once the model error exceeds a specific threshold,online adaptation rules are implemented separately to correct the plant model mismatch via a recursive least squares (RLS) algorithm.Because the IMC extracts the inverse of the minimum part of the internal model as its structure,the IMC controller is self-tuned by explicitly updating the parameters,which are parts of the internal model.Both parameter convergence and system stability are briefly analyzed,and proved to be effective.Finally,the proposed control scheme is tested and evaluated using a widely-used benchmark of a multi-input multi-output (MIMO) system with pure delay.展开更多
基金supported by Philosophy and Social Sciences Planning Project of Guangdong Province[Grant No.GD24CTS08].
文摘Digital transformation provides enterprises with new development momenta.Understanding the relationship between digital transformation and total factor productivity(TFP)is essential.This study employs a fixedeffect model and selects all Chinese A-share listed companies from 2007 to 2022 as the research sample.Internal control(IC)is introduced as a mechanistic variable.The results indicate that digital transformation significantly promotes both TFP and the effectiveness of IC.Moreover,effective IC plays a significant mediating role in the relationship between digital transformation and TFP.A heterogeneity analysis reveals that,compared to non-state-owned enterprises,state-owned enterprises can improve TFP more rapidly through digital transformation due to their resource advantages and policy support.On the one hand,these findings help enterprises better align their transformation strategies to maximize the benefits of digital transformation.On the other hand,they provide investors with insights into the transformation potential and future growth prospects of these enterprises.
文摘Under the background of increasingly complex global economic development and financial markets,the legal risks faced by enterprises are increasingly intensified.As an important legal norm to adjust financial activities,financial law has put forward higher requirements for the operation and risk management of enterprises.Therefore,the article will start from the concept of internal legal risk prevention and control under the financial perspective,study and analyze the common internal legal risks and the causes of risks,and put forward the specific measures of prevention and control of internal legal risks.
文摘With the development of modern society,the functions of administrative institutions and public institutions are constantly evolving.Under the background of comprehensively deepening reform,higher requirements are put forward for the financial management of administrative institutions and public institutions.The financial management status of administrative institutions and public institutions will directly affect the quality of public services.Therefore,it is necessary to strengthen the internal control of financial management.By leveraging the constraints and supervision mechanisms of internal control,the transparency and credibility of financial management can be effectively enhanced.However,in the actual internal control and financial management of administrative institutions and public institutions,there are still some problems,which make it difficult to improve the level of financial management and affect the sustainable development of administrative institutions and public institutions.By analyzing the internal control and financial management of administrative institutions and public institutions under the new situation,this article proposes plans such as strengthening the construction of professional management teams,deeply using information technology means,and improving the internal control system,effectively enhancing the management efficiency of administrative institutions and public institutions and better adapting to the development of the times.
基金supported by the National Natural Science Foundation of China(NSFC)(Grant No.U1860111).
文摘The propagation form of internal cracks induced by continuous casting soft reduction and the control strategy for enhancing the internal quality of 45 steel through industrial trials and a three-dimensional flow-heat transfer-solidification coupling model were investigated.The results showed that the internal cracks induced by soft reduction exhibited a characteristic of being"coarse in the middle and fine at both ends",and displayed an elliptical arc distribution on the loose side of the strand cross section.The cracks originated within the brittle temperature range and propagated inward to the liquid impenetrable temperature and outward to the zero ductility temperature or below.The control strategy for enhancing the internal quality of the 45 steel strand through soft reduction is to adjust the casting speed or the reduction zone appropriately,ensuring that the central solid fraction of the reduction zone falls within the range of 0.33-0.99.At this point,a reasonable reduction amount is allocated to eliminate the center shrinkage cavities and center segregation,even if it results in minor reduction-induced cracks.
基金Project supported by the National Natural Science Foundation of China(Grant No.62275272)the Training Program for Excellent Young Innovators of Changsha(Grant No.KQ2305025)。
文摘Coherent beam combining(CBC) of fiber laser array is a promising technique to realize high output power while maintaining near diffraction-limited beam quality. To implement CBC, an appropriate phase control feedback structure should be established to realize phase-locking. In this paper, an innovative internal active phase control CBC fiber laser array based on photodetector array is proposed. The dynamic phase noises of the laser amplifiers are compensated before being emitted into free space. And the static phase difference compensation of emitting laser array is realized by interference measurement based on photodetector array. The principle of the technique is illustrated and corresponding simulations are carried out, and a CBC system with four laser channels is built to verify the technique. When the phase controllers are turned on, the phase deviation of the laser array is less than λ/20, and ~ 95% fringe contrast of the irradiation distribution is obtained. The technique proposed in this paper could provide a reference for the system design of a massive high-power CBC system.
文摘Small and medium-sized enterprises(SMEs)constitute the primary drivers of production within the nation’s existing enterprise landscape.They represent the most dynamic segment of the national economy and play a pivotal role in supporting economic growth,fostering employment,and enhancing people’s livelihoods.However,despite their significant and extensive organizational structures,only a fraction of these companies have established internal control systems,and even fewer possess robust ones.Building upon this premise and considering the prevailing circumstances of SMEs,this paper undertakes an empirical analysis of monetary fund management within this sector.It delves into the operational intricacies,exploring how monetary funds should be effectively implemented to ensure their safety and integrity.Furthermore,it proposes viable strategies to enhance the circulation efficiency of monetary funds,thereby maximizing benefits for enterprises.Addressing these challenges is crucial for SME managers striving to achieve sustainable profit growth and navigate the complexities of financial management.
文摘As an important pillar of national economic development,state-owned enterprises,their operational efficiency,and risk management ability are directly related to the stability and security of the national economy.As an important part of enterprise management,internal control management plays an irreplaceable role.Especially in the current domestic and international economic situation is complex and changeable,market competition is increasingly fierce environment,to strengthen the internal control management of state-owned enterprises and risk prevention measures is particularly important.This paper starts with the importance of internal control management and risk prevention for state-owned enterprises,and analyzes the problems and strategies in the internal control management and risk prevention of state-owned enterprises,in order to build a more comprehensive and efficient risk management system for state-owned enterprises to adapt to the ever-changing market environment and realize sustainable development.
文摘Fixed assets in universities occupy an important position in university management due to their wide coverage and large amount of money.Due to insufficient funding supply,private universities mainly focus on the allocation and utilization of fixed assets,which reflects the overall characteristics of cautious allocation,maximum utilization,and delayed elimination in the actual management of fixed assets.This article aims to conduct research and analysis on the entire lifecycle process of the allocation,use,and disposal of fixed assets in private universities,summarize the problems existing in the internal control of fixed assets in private universities,and propose corresponding countermeasures and suggestions in a targeted manner.
文摘This paper outlines the internal control management of hospital accounting and finance,introducing its concept,importance,and objectives.It then analyzes the problems existing in the internal control management of hospital accounting and finance,including an unsound management system,insufficient system implementation,inadequate risk assessment and control capabilities,poor information communication,weak internal supervision,and uneven personnel quality.The reasons for these problems are also analyzed,including outdated management concepts,irrational organizational structures,imperfect training and incentive mechanisms,low levels of information technology,and changes in the external environment.This paper proposes improvement measures for the internal control management of hospital accounting,including enhancing the management system,strengthening system implementation,improving risk assessment and control capabilities,enhancing the information communication mechanism,strengthening internal supervision,improving personnel quality,advancing information technology,and adapting to changes in the external environment.
文摘The quality system of any modern pharmaceutical company is the pharmaceutical quality system(PQS),which extends the GMP standards to all stages of the medicinal productslife cycle,from pharmaceutical development to its withdrawal from production.The principal difference between PQS and GxP rules from other quality systems is that the medicinal product,its safety and efficacy is put at the forefront.At the same time,PQS implies a process approach to all components that should be aimed at achieving the main goal—ensuring and guaranteeing the quality of the medicinal product for the end user(patient)—and should be based on the quality risk management system.An integral part of PQS,as well as the GxP rules adopted in the European Union and PIC/S,is a process for self-inspections and/or quality audits,which regularly appraises the effectiveness and applicability of the PQS.This publication is dedicated to the definition of self-inspections(internal audits)as one of the PQS’s processes.The article defines the main standard stages and develops a model of a risk-based approach to the self-inspections’planning in relation to processes of the pharmaceutical quality system.
基金co-supported by the National Major Project for the Development and Application of Scientific Instrument Equipment of China (No. 2012YQ040235)
文摘The start-up current control of the high-speed brushless DC（HS-BLDC） motor is a challenging research topic. To effectively control the start-up current of the sensorless HS-BLDC motor, an adaptive control method is proposed based on the adaptive neural network（ANN）inverse system and the two degrees of freedom（2-DOF） internal model controller（IMC）. The HS-BLDC motor is identified by the online least squares support vector machine（OLS-SVM） algorithm to regulate the ANN inverse controller parameters in real time. A pseudo linear system is developed by introducing the constructed real-time inverse system into the original HS-BLDC motor system. Based on the characteristics of the pseudo linear system, an extra closed-loop feedback control strategy based on the 2-DOF IMC is proposed to improve the transient response performance and enhance the stability of the control system. The simulation and experimental results show that the proposed control method is effective and perfect start-up current tracking performance is achieved.
基金Sponsored by the Fundamental Research Funds for the Central Universities(Grant No.N110304008)the National Natural Science Foundation of China(Grant No.61374137)
文摘A modified two-degrees-of-freedom( M-TDOF) internal model control( IMC) method is proposed for non-square systems with multiple time delays and right-half-plane( RHP) zeros. In this method,pseudo-inverse is introduced to design the internal model controller,and a desired closed-loop transfer function is designed to eliminate the unrealizable factors of the derived controller. In addition,set-point tracking and load-disturbance rejection of each process are separately controlled by two controllers. The simulation results show that in addition to high decoupling performance and robustness,the proposed control method also effectively improves loaddisturbance rejection and simultaneously optimizes the input tracking performance and disturbance rejection performance by selecting the parameters of controllers. Furthermore,the higher tolerance of model mismatch is achieved in this paper.
基金The National High Technology Research&Development Program of China under contract No.2012AA10A411the National Natural Science Foundation of China under contract Nos 41176151 and 41276177
文摘Pyropia haitanensis is an economically important mariculture crop in China and has a high research value for several life phenomena, for example environmental tolerance. To explore the mechanisms underlying these characteristics, gene expression has been investigated at the whole transcriptome level. Gene expression studies using quantitative real-time PCR should start by selecting an appropriate internal control gene; therefore, the absolute expression abundance of six housekeeping genes （18S rRNA （18S）, ubiquitin-conju-ating enzyme （UBC）, actin （ACT）, β-tubulin （TUB）, elongation factors 2 （EF2）, and glyceraldehyde-3-phos- phate dehydrogenase （GAPDH） examined by the quantitative real-time PCR in samples corresponding to different strains, life-cycle stages and abiotic stress treatments. Their expression stabilities were assessed by the comparative cycle threshold （Ct） method and by two different software packages： geNorm and NormFinder. The most stable housekeeping gene is UBC and the least stable housekeeping is GADPH. Thus, it is proposed that the most appropriate internal control gene for expression analyses in P. haitanensis is UBC. The results pave the way for further gene expression analyses of different aspects of P. haitanensis biology including different strains, life-history stages and abiotic stress responses.
基金supported by the National Basic Research Program (973) of China (No.2015CB458900)the National Natural Science Foundation of China (No.51779002)
文摘Denitrification plays an important role in nitrogen(N) removal in freshwater ecosystems.This internal process regulates the fluctuations of N concentration, especially for lakes with high nutrients concentrations and long residence time. Lakes in Yunnan plateau(southwestern China) provide typical cases, while studies in this region have been rare.Therefore, we studied denitrification of two lakes(Lake Dianchi in hypereutrophic state and Lake Erhai in mesotrophic) in this region. We used acetylene inhibition technique to quantify potential denitrification rate(PDR) of these lakes in April and August, 2015 and 2016. PDR of the sediments ranged 0–1.21 μmol/(N·m^2·hr), and that of overlying water ranged 0–0.24 μmol/(N·L·hr). Then, we used Least Angle Regression to determine the controlling factors for denitrification. Nutrients controlled PDR from two aspects: providing essential nitrogen sources; and affecting the richness and metabolism of denitrifying bacteria. In April, both aspects limited PDR; while only nitrogen sources limited PDR in August, due to depleted nitrate and enhanced denitrifying bacteria activity. Ammonia was most significant to denitrification, indicating that nitrate from nitrification transported to the bottom of wellmixed lake provide major N source by denitrification. The high PDR and low nitrate concentrate in August were evidence of an enhanced internal N cycling by algal blooms.
基金supported by National Basic Research Program of China(973 Program)(No.2012CB316400)National Natural Science Foundation of China(Nos.61171034 and 61273134)
文摘In this paper, an iterative learning control algorithm is proposed for discrete linear time-varying systems to track iterationvarying desired trajectories. A high-order internal model(HOIM) is utilized to describe the variation of desired trajectories in the iteration domain. In the sequel, the HOIM is incorporated into the design of learning gains. The learning convergence in the iteration axis can be guaranteed with rigorous proof. The simulation results with permanent magnet linear motors(PMLM) demonstrate that the proposed HOIM based approach yields good performance and achieves perfect tracking.
基金Project(61273132)supported by the National Natural Foundation of ChinaProject(20110010010)supported by Higher School Specialized Research Fund for the Doctoral Program,China
文摘A novel control scheme of active disturbance rejection internal model control(ADRIMC) is proposed to improve the anti-interference ability and robustness for the dead-time process. The active anti-interference concept is introduced into the internal model control(IMC) by analyzing the relationship between IMC and disturbance observer control(DOB). Further, a design process of disturbance filter is presented to realize the active anti-interference ability for ADRIMC scheme. The disturbance filter is used to estimate an equivalent disturbance consisting of both external disturbances and internal disturbances caused by model mismatches.Simulation results demonstrate that the proposed method possesses a good disturbance rejection performance, though losing some partial dynamic performance. In other words, the proposed method shows a tradeoff between the dynamic performance and the system robust.
基金Supported by the National Natural Science Foundation of China（60574047） the National High Technology Research and Development Program of China（2007AA04Z168 2009AA04Z154） the Research Fund for the Doctoral Program of Higher Education in China（20050335018）
文摘In this paper,a multi-loop internal model control(IMC) scheme in conjunction with feed-forward strategy based on the dynamic partial least squares(DyPLS) framework is proposed.Unlike the traditional methods to decouple multi-input multi-output(MIMO) systems,the DyPLS framework automatically decomposes the MIMO process into a multi-loop system in the PLS subspace in the modeling stage.The dynamic filters with identical structure are used to build the dynamic PLS model,which retains the orthogonality among the latent variables.To address the model mismatch problem,an off-line least squares method is applied to obtain a set of optimal filter parameters in each latent space.Without losing the merits of model-based control,a simple and easy-tuned IMC structure is readily carried over to the dynamic PLS control framework.In addition,by projecting the measurable disturbance into the latent subspace,a multi-loop feed-forward control is yielded to achieve better performance for disturbance rejection.Simulation results of a distillation column are used to further demonstrate this new strategy outperforms conventional control schemes in servo behavior and disturbance rejection.
基金Supported by National Natural Science Foundation of China(Grant No.51375009)PhD Research Foundation of Liaocheng University,China(Grant No.318051523)Tsinghua University Initiative Scientific Research Program,China
文摘Because of vehicle＇s external disturbances and model uncertainties,robust control algorithms have obtained popularity in vehicle stability control.The robust control usually gives up performance in order to guarantee the robustness of the control algorithm,therefore an improved robust internal model control（IMC） algorithm blending model tracking and internal model control is put forward for active steering system in order to reach high performance of yaw rate tracking with certain robustness.The proposed algorithm inherits the good model tracking ability of the IMC control and guarantees robustness to model uncertainties.In order to separate the design process of model tracking from the robustness design process,the improved 2 degree of freedom（DOF） robust internal model controller structure is given from the standard Youla parameterization.Simulations of double lane change maneuver and those of crosswind disturbances are conducted for evaluating the robust control algorithm,on the basis of a nonlinear vehicle simulation model with a magic tyre model.Results show that the established 2-DOF robust IMC method has better model tracking ability and a guaranteed level of robustness and robust performance,which can enhance the vehicle stability and handling,regardless of variations of the vehicle model parameters and the external crosswind interferences.Contradiction between performance and robustness of active steering control algorithm is solved and higher control performance with certain robustness to model uncertainties is obtained.
基金Project supported by the National Natural Science Foundation of China (No.60574047)the National High-Tech R & D Program (863)of China (No.2007AA04Z168)the Research Fund for the Doctoral Program of Higher Education of China (No.20050335018)
文摘A multi-loop adaptive internal model control (IMC) strategy based on a dynamic partial least squares (PLS) frame-work is proposed to account for plant model errors caused by slow aging,drift in operational conditions,or environmental changes.Since PLS decomposition structure enables multi-loop controller design within latent spaces,a multivariable adaptive control scheme can be converted easily into several independent univariable control loops in the PLS space.In each latent subspace,once the model error exceeds a specific threshold,online adaptation rules are implemented separately to correct the plant model mismatch via a recursive least squares (RLS) algorithm.Because the IMC extracts the inverse of the minimum part of the internal model as its structure,the IMC controller is self-tuned by explicitly updating the parameters,which are parts of the internal model.Both parameter convergence and system stability are briefly analyzed,and proved to be effective.Finally,the proposed control scheme is tested and evaluated using a widely-used benchmark of a multi-input multi-output (MIMO) system with pure delay.
