Research on the Problems and Countermeasures of Monetary Capital Internal Control in Small and Medium-Sized Enterprises

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.

Feedback control scheme of traffic jams based on the coupled map car-following model

Based on the pioneering work of Konishi et al. [Phys. Rev. E （1999） 60 4000], a new feedback control scheme is presented to suppress traffic jams based on the coupled map car-following model under the open boundary condition. The effect of the safe headway on the traffic system is considered. According to the control theory, the condition under which traffic jams can be suppressed is analyzed. The results are compared with the previous results concerning congestion control. The simulations show that the suppression performance of our scheme on traffic jams is better than those of the previous schemes, although all the schemes can suppress traffic jams. The simulation results are consistent with theoretical analyses.

GROUP VELOCITY CONTROL SCHEME WITH LOW DISSIPATION

In order to prevent smearing the discontinuity, a modified term is added to the third order Upwind Compact Difference scheme to lower the dissipation error. Moreover, the dispersion error is controled to hold back the non physical oscillation by means of the group velocity control. The scheme is used to simulate the interactions of shock density stratified interface and the disturbed interface developing to vortex rollers. Numerical results are satisfactory.

Design of process and control scheme for cyclohexanol production from cyclohexene using reactive distillation

Cyclohexanol is a commonly used organic compound.Currently,the most promising industrial process for synthesizing cyclohexanol,by cyclohexene hydration,suffers from a low conversion rate and difficult separation.In this paper,a three-column process for catalytic distillation applicable in the hydration of cyclohexene to cyclohexanol was established to solve these.Simulation with Aspen Plus shows that the process has good advantages,the conversion of cyclohexene reached 99.3%,and the product purity was>99.2%.The stable operation of the distillation system requires a good control scheme.The design of the control scheme is very important.However,at present,the reactive distillation process for cyclohexene hydration is under investigation experimentally and by steady-state simulation.Therefore,three different plant-wide control schemes were established(CS1,CS2,CS3) and the position of temperature sensitive stage was selected by using sensitivity analysis method and singular value decomposition method.The Tyreus-Luyben empirical tuning method was used to tune the controller parameters.Finally,Aspen Dynamics simulation software was used to evaluate the performance of the three control schemes.By introducing ΔF±20% and χ_(ENE)±5%,comparison the changes in product purity and yield of the three different control schemes.By comparison,we can see that the control scheme CS3 has the best performance.

CONTROL SCHEMES FOR CMAC NEURAL NETWORK-BASED VISUAL SERVOING

In IBVS (image based visual servoing), the error signal in image space should be transformed into the control signal in the input space quickly. To avoid the iterative adjustment and complicated inverse solution of image Jacobian, CMAC (cerebellar model articulation controller) neural network is inserted into visual servo control loop to implement the nonlinear mapping. Two control schemes are used. Simulation results on two schemes are provided, which show a better tracking precision and stability can be achieved using scheme 2.

Overall Evaluation of the Control Schemes of Automobile Pollution and Its Multi-Target Decision

Various control schemes of automobile pollution are comprehensively evaluated by using the weighting and feyzzy methods, from which several feasible schemes are selected, and then mulit-target decision is made by using the minimum distance and hierarcby analysis methods, for determining the optimal control methods of automobile pollution.

A Dual-Channel Secure Transmission Scheme for Internet-Based Networked Control Systems

Two significant issues in Internet-based networked control systems （ INCSs）, transport performance of different protocols and security breach from Internet side, are investigated. First, for improving the performance of data transmission, user datagram protocol （UDP） is adopted as the main stand for controllers and plants using INCSs. Second, a dual-channel secure transmission scheme （DCSTS）based on data transmission characteristics of INCSs is proposed, in which a raw UDP channel and a secure TCP （transmission control protocol） connection making use of SSL/TLS （secure sockets layer/transport layer security） are included. Further, a networked control protocol （NCP） at application layer for supporting DCSTS between the controllers and plants in INCSs is designed, and it also aims at providing a universal communication mechanism for interoperability of devices among the networked control laboratories in Beijing Institute of Technology of China, Central South University of China and Tokyo University of Technology of Japan. By means of a networked single-degree-of-free- dom robot arm, an INCS under the new protocol and security environment is created. Compared with systems such as IPSec or SSL/TLS, which may cause more than 91% network throughput deduction, the new DCSTS protocol may yield results ten times better, being just 5.67%.

Control schemes for synchronizing two subnetworks with weak couplings

In this paper, we propose a well-designed network model with a parameter and study full and partial synchronization of the network model based on the stability analysis. The network model is composed of a star-coupled subnetwork and a globally coupled subnetwork. By analyzing the special coupling configuration, three control schemes are obtained for synchronizing the network model. Further analysis indicates that even if the inner couplings in each subnetwork are very weak, two of the control schemes are still valid. In particular, if the outer coupling weight parameter 0 is larger than （n2 - 2n）/4, or the subnetwork size n is larger than 02, the two subnetworks with weak inner couplings can achieve synchronization. In addition, the synchronizability is independent of the network size in case of 0 〈 0 〈 n/（n ＋ 1 ）. Finally, we carry out some numerical simulations to confirm the validity of the obtained control schemes. It is worth noting that the main idea of this paper also applies to any network consisting of a dense subnetwork and a sparse network.

Control Scheme Discussion for Bottom Oil Slurry System of FCCU Fractionator

流化催化裂化装置（FCCU）分馏塔底油浆系统的控制效果对整个装置的平稳安全运行具有重要意义。近年来国内新建了许多大型FCCU，既包含国内各设计院自己的技术，也有部分引进国外的工艺包，其分馏塔底油浆系统的控制方案也有多种形式。总结了近年来国内新建FCCU常用的三种较为典型的油浆系统控制方案，阐述了各方案的特点，对其进行了简要的对比和分析。在此基础上尝试性地提出了这三种方案的适用场合，方便设计人员根据每个项目的特点设计合理的控制方案，达到最佳控制效果。

Research on the cooperative train control method in the metro system for energy saving

Purpose–To address the problem that the current train operation mode that train selects one of several offline pre-generated control schemes before the departure and operates following the scheme after the departure,energy-saving performance of the whole metro system cannot be guaranteed.Design/methodology/approach–A cooperative train control framework is formulated to regulate a novel train operation mode.The classic train four-phase control strategy is improved for generating specific energy-efficient control schemes for each train.An improved brute force(BF)algorithm with a two-layer searching idea is designed to solve the optimisation model of energy-efficient train control schemes.Findings–Case studies on the actual metro line in Guangzhou,China verify the effectiveness of the proposed train control methods compared with four-phase control strategy under different kinds of train operation scenarios and calculation parameters.The verification on the computation efficiency as well as accuracy of the proposed algorithm indicates that it meets the requirement of online optimisation.Originality/value–Most existing studies optimised energy-efficient train timetable or train control strategies through an offline process,which has a defect in coping with the disturbance or delays effectively and promptly during real-time train operation.This paper studies an online optimisation of cooperative train control based on the rolling optimisation idea,where energy-efficient train operation can be realised once train running time is determined,thus mitigating the impact of unpredictable operation situations on the energy-saving performance of trains.

Application Strategy of PLC Technology in Energy-Saving Control of Tunnel Lighting

In this study,we investigated on the application of planar lightwave circuit(PLC)technology in energy-saving control of tunnel lighting.The application status of PLC in the field of energy saving followed by the necessity of energy saving in tunnel lighting was analyzed.Finally,the application of PLC in tunnel lighting energy-saving control around the three dimensions of system overall architecture design,control scheme,and program control process was investigated.The results showed that the system meets the requirements of control effect,robustness,and visual effect after trial operation,and is suitable for practical applications.

海绵城市背景下合流制改造及溢流污染控制路径研究

我国合流制排水管渠数量多、建设情况复杂、运行问题突出,已成为当前制约城市水环境质量提升的关键,在系统化全域推进海绵城市建设的背景下,合流制系统改造及溢流污染控制成为许多城市的重点任务。根据多年城市建设统计年鉴数据对我国城市合流制排水管渠数量、分布及逐年变化情况进行分析;梳理我国城市合流制管渠系统状况、存在问题及当前海绵城市建设、黑臭水体治理、内涝综合整治、污水提质增效工作对合流制系统的相关要求,在此基础上提出适用于我国城市合流制系统的界定与评价方法;结合当前各城市在推进相关工作过程中存在的问题,提出海绵城市建设背景下合流制系统改造及溢流污染控制路径,即因地制宜制定合流制改造及溢流污染控制系统化方案,并明确系统化方案编制流程及技术要点。

无刷双馈电机研究综述与展望

无刷双馈电机具有结构可靠、变频器容量小等优势,非常适合灵活运行于防爆、易燃等特殊或极端工况,近年来受到广泛关注。该文根据无刷双馈电机的基本工作原理,明确了该类电机的命名原则与规范名称;总结了现有定转子方案的结构及性能特点,综合考虑性能指标与结构工艺,提出了转子双套绕组的发展方向;梳理了无刷双馈电机的稳态等效电路模型及基于各类数学模型的优化设计方法,针对现存难以完整考虑不同转速工况性能的不足,阐明了利用新型同步-异步相串联等效电路进行优化设计的思路;对比分析了经典及新近出现的无刷双馈电机控制系统拓扑和控制策略特点,面向典型电动、发电工况建立了完整的电机及控制系统。最后,对无刷双馈电机的上述理论研究问题及工业应用的发展方向进行了总结阐述,为该类电机的深入研究及加快推广应用提供参考和指导。

计及DoS攻击和通信时滞的电力系统负荷频率控制

针对电力系统通信网络中存在的时滞和DoS攻击现象,本文提出了基于采样特性的电力系统离散负荷频率控制方案。首先,计及电力系统负荷波动的情况,在多区域电力系统负荷频率控制系统(LFC)模型的基础上,将通信网络中DoS攻击的危害量化为采样信号连续丢失数,并分别考虑通信网络中通信时滞和输出信号采样特性,建立包含输出状态反馈控制器的电力系统LFC模型。其次,基于此模型,利用含有控制命令更新周期、DoS攻击导致的最大采样信号连续丢失数、通信时滞、H_(∞)稳定指标的双边闭环Lyapunov泛函、LMI技术,提出LFC系统满足一定H_(∞)指标的稳定准则,并给出离散状态输出反馈LFC控制器的设计及求解方法。最后,本文以单区域和双区域LFC系统为例进行了仿真验证。结果表明:与已有文献方法相比,本文方法在保持系统H_(∞)渐近稳定前提下,能够容忍更大的通信时滞,且结果的保守性更低;同时可以看出本文所设计的控制器在保证H_(∞)稳定性能的基础上,对一定能量限制的DoS攻击具有弹性的防御性能。因此本文方案的有效性和优越性得到了验证。

严寒地区地源热泵供热系统运行优化研究

地源热泵供热系统在运行控制方案上的优化,是建筑节能降耗的重要途径。以沈阳市ST办公楼地源热泵系统为研究对象,实地调研获取能源系统运行参数,归纳地源热泵的运行特性,锁定实际建筑中地源热泵系统供热现存问题,利用遗传算法寻求地源热泵系统最优运行控制参数。利用TRNSYS模拟能源系统运行,通过比较系统原有的改变机组负载率的控制方案与优化后最优运行控制参数方案的系统耗电量和性能系数,预测最佳控制方案下地源热泵系统的优化效果。结果表明:在最优运行控制方案下,地源热泵系统性能显著提升,系统耗电量降低14.5%,系统性能系数(COP)提升23.8%,热泵机组耗电量降低15.1%,地源热泵系统运行更加高效节能。

瘀滞型肩关节周围炎中医优化方案筛选研究

目的基于随机对照试验进行中医临床治疗优化方案的筛选研究,明确中医治疗瘀滞型肩关节周围炎的最佳临床方案。方法选取2020年6月-2021年12月在长春中医药大学附属医院门诊就诊的瘀滞型肩关节周围炎患者99例,随机分为A、B、C组,3组常规进行推拿及功能锻炼治疗,在此基础上A组联合药物疗法,B组联合针灸疗法,C组联合药物疗法及针灸疗法,疗程2周,于治疗后1周、2周及3个月对患者进行随访。以视觉模拟标尺评分(visual analogue scale,VAS评分)、Constant-Murley肩关节评分量表、肩关节活动范围、红细胞沉降率(erythrocyte sedimentation rate,ESR)及生化指标评价疗效和安全性。结果共92例患者完成研究。相较于本组治疗前,3组在治疗后1周、2周及3个月VAS评分、Constant-Murley肩关节评分、肩关节活动范围有显著改善(P<0.05),完成治疗后ESR有显著改善(P<0.05),肝肾生化指标无统计学意义(P>0.05)。3组组间比较,治疗后1周疗效无统计学意义(P>0.05),C组2周后及3个月效果明显优于A、B组(P<0.05)。完成治疗后的ESR及肝肾生化指标水平无统计学意义(P>0.05)。3组均未发现严重不良事件,不良反应发生率3组比较,差异无统计学意义(P>0.05)。结论针刺、中药内服及外用等疗法对于瘀滞型肩关节周围炎患者的疼痛和活动受限具有显著疗效,能明显地提高患者的生活质量,综合应用中医治疗手段2周后的中远期疗效明显优于单一手段。

基于AQUATOX模拟的小球藻处理水产养殖废水试验

目的 为实现低碳快捷处理水产养殖废水,探究利用小球藻处理废水的最优方案。方法 以某鲅鱼养殖基地水体为对象,利用AQUATOX软件建立水生态环境模型,根据不同的水产养殖废水浓度、水力停留时间和流量建立5个试验组,稀释后投加5 mg/L的小球藻藻种,模拟分析小球藻的处理效果,并将结果与实测数据进行对比。结果 投加小球藻的最适比例为:ρ(小球藻)∶ρ(TN)∶ρ(NH_(3)-N)∶ρ(TP)∶ρ(CODcr)=1∶16.8∶3.2∶0.8∶40;最适投加比例的小球藻对废水中的TN、TP、NH_(3)-N、CODCr的处理效率分别达到了73%、72.5%、94%、75%;藻生物量也达到了初始值的26倍。结论 应用AQUATOX模型可以快速实现小球藻处理水产养殖废水方案优化,TN、TP、NH_(3)-N和CODcr质量浓度模拟结果的平均相对误差分别为0.32%、2.52%、4.83%和0.10%。