VAF V92 MODAL 1003微电脑粘度自动调节系统故障排除实例

我校在1988年引进的VAF微电脑粘度自动调节系统由四大部份组成:第一部份为微电脑粘度计,它的型号为V92 1003(见图1左边所示),该型号粘度计是由单片机控制的,机内包括二台调节器,其中一台为反作用式的温度程序控制器,用于轻重油自动切换过程中的温度程序控制;另一台为正作用式的粘度调节器,用于温度程序控制达标以后的粘度控制.第二部份为测粘计(图1),它的任务是把燃油粘度转换成4～20毫安电流信号,送到调节器的1和2接线柱,在测粘计上还安装了一只PT-100温度传感器。

PVC穿线管台灯的设计与制作

台灯作为我们日常工作和学习的局部照明工具,具有小巧玲珑、开关方便、移动自由等特点,比如具备自动调光、播放音乐、调节计时等功能,甚至还能像机器人一样会跳舞。 今天,我们就利用废弃的pvc管材,亲自动手设计制作几款台灯!

Robust Non-fragile PID Controller Design for the Stroke Regulation of Metering Pumps

This job focuses on the stroke regulation of a class of high-precision metering pumps.A parametertuning method of robust non-fragile PID（proportional-integral-derivative）controllers is proposed with the assumption that a PID controller has additive gain perturbations.An H-infinite robust PID controller can be obtained by solving a linear matrix inequality.This approach can guarantee that the closed-loop control systems is asymptotically stable and the H-infinite norm of the transfer function from the disturbance to the output of a controlled system is less than a given constant to attenuate disturbances.The simulation case shows that the control performance of the proposed strategy is significantly better than the traditional PID approach in the situation with perturbations of controller parameters.

ANALYSIS AND CALCULATION OF REGULATED WATER RESOURCES OF GROUNDWATER RESERVOIR

Groundwater reservoir is a kind of important engineering, which can optimize water resources arran- gement by means of artificial regulation. Regulated water is the blood and value performance of groundwater reservoir. To resolve the problem of real-time quantification of regulated water, the paper analyzed sources and compositions of regulated water in detail. Then, under the conditions of satisfying water demand inside research area, the paper analyzed quantity available and regulation coefficient of different regulated water and established a formula to calculate regulated water. At last, based on a pore groundwater reservoir in the middle reaches of the Yinma River, Jilin Province, the paper calculated regulated water with the formula and the result shows that the method is feasible. With some constraint conditions, the formula can be adopted in other similar areas.

Optimization design of an electroabsorption modulator integrated with spot-size converter

A novel 1.55 μm spot-size converter integrated with electroabsorption modulator is designed and fabricated with conventional photolithography and chemical wet etching process.For the modulator,we employed a deeply-etched ridge waveguide structure with polyimide on each side of its walls.For the spot-size converter,we employed a buried double-core structure in which a ridge-based passive waveguide is incorporated.The wide and thin passive waveguide is optically combined with a laterally tapered active waveguide to control the mode size.By simulation,the figure of merit is 4.17(dB/V/(100 μm)) and the beam divergence angles in the horizontal and vertical directions are as small as 11.2°×13.0°,respectively.

便携式转台

刷镀、喷涂两用便携式转台由中国机械工程学会表面工程研究所最新研制。

System design and analysis of the trans-critical carbon-dioxide automotive air-conditioning system

As an environmentally harmless and feasible alternate refrigerant, CO 2 has attracted worldwide attention, especially in the area of automobile air conditioning (AAC). The thermal property of CO 2 and its trans critical refrigeration cycle is very different from that of the traditional CFC or HCFC system. The detailed process of CO 2 system thermal cycle design and optimization is described in this paper. System prototype and performance test bench were developed to analyze the performance of the CO 2 AAC system.

A simple anti-windup method for the Modified Smith Predictor

For the first-order integrating processes with long delay, a Modified Smith Predictor (MSP) was analyzed when the control signal saturated. If the MSP controller has no anti-windup scheme, the saturation effectively chops off the control input resulting in performance deterioration. Thus, a simple and effective anti-windup scheme, without an additional parameter, is designed for the MSP. Simulation results illustrate that the proposed method may achieve good performance under the nominal and model uncertainty cases.

Auditing in the 21 st Century： Has Self-regulation Failed？＊

From the very beginning, auditing is pretty much a self-regulated follow in practice. But the plethora of recent corporate failures profession and has some ethical rules of thumb to and scandals where auditors＇ instrumental role is evident in many instances raise question about the validity and suitability of ＂self-regulation＂ in auditing, especially in the 21st century where auditors need to perform auditing in ever complex risk management process. Moreover, to restore the market confidences within the auditing profession and to raise the overall audit quality, many countries are establishing some super regulatory bodies to oversee the functions of auditing and auditors. Based on the ＂documentary research methodology＂, the author examines whether ＂self-regulation＂ in auditing has completely failed in the 21 st century. The author reveals that ＂self-regulation＂ in auditing has not completely failed; rather, a joint approach is needed to raise the overall quality of auditing where there will be equilibrium between ＂self-regulation＂ and statutory directive.

Unbiased parameter estimation of continuous-time system based on modulating functions with input and output white noises

An efficient unbiased estimation method is proposed for the direct identification of linear continuous-time system with noisy input and output measurements.Using the Gaussian modulating filters,by numerical integration,an equivalent discrete identification model which is parameterized with continuous-time model parameters is developed,and the parameters can be estimated by the least-squares (LS) algorithm.Even with white noises in input and output measurement data,the LS estimate is biased,and the bias is determined by the variances of noises.According to the asymptotic analysis,the relationship between bias and noise variances is derived.One equation relating to the measurement noise variances is derived through the analysis of the LS errors.Increasing the degree of denominator of the system transfer function by one,an extended model is constructed.By comparing the true value and LS estimates of the parameters between original and extended model,another equation with input and output noise variances is formulated.So,the noise variances are resolved by the set of equations,the LS bias is eliminated and the unbiased estimates of system parameters are obtained.A simulation example by comparing the standard LS with bias eliminating LS algorithm indicates that the proposed algorithm is an efficient method with noisy input and output measurements.

Using a Computer Driven PID Regulator for Controlling the Vacuum Pump of a Mechanical Milking Machine

Conventional vacuum control in a milking system is accomplished by using a vacuum pump, sized for the maximum air flows into the milking system, running at a full speed. The difference between the pump capacity and the necessary flow of air is compensated by allowing air to enter the system through a regulator. The solution presented in this paper uses a VFD （variable frequency driver） in order to drive the vacuum pump at a controlled speed, so that the air removed equals the air entering the milking system. The VFD technology is able to adjust the rate of air removal from the milking system, by changing the speed of the vacuum pump motor. The VFD is controlled by a computer using a virtual instrument in order to emulate a PID （proportion integration differentiation） regulator. The tests aimed to evaluate the vacuum regulator characteristics and vacuum stability. A statistical analysis of the experimental results was performed and it showed that there was a significant difference between the experimental results obtained for the two methods of vacuum regulation （with vacuum regulator and VFD controller respectively）. The experimental results proved that the used of the VFD controller led to a higher vacuum stability in terms of the error between the set vacuum value and the achieved values.

Analysis of the hotspots and trends in traditional Chinese medicine immunomodulation research based on bibliometrics

Objective To analyze the intellectual structure,hotspots and trends of traditional Chinese medicine(TCM)in immune regulation research.Methods The data were extracted from the Web of Science Core Collection(WoSCC)and the China National Knowledge Infrastructure(CNKI)and verified by two experienced TCM researchers.The time of literature retrieval is up to 2020.CiteSpace 5.7.R1 and Microsoft Excel 2016 were used for the statistical analysis and bibliometric diagrams,including the co-occurrence network of authors,institutions,countries,keywords,references,dual-map overlays of journals and citation bursts,etc.Results A total of 12270 publications related to TCM in immune regulation were included.The annual number of publications has increased in this field.There was close cooperation of countries and institutions,while the distribution of scholars was scattered.China was the core of the cooperation network.The dual-map overlays analysis of journals showed that core and marginal fields had increased.The keywords and references analysis showed that network pharmacology,metabolism and cancer were the most high-frequency keywords with high-intensity bursts.Conclusion TCM in immune regulation has attracted wider attention,with multi-country,multi-field,multi-disciplinary and multi-level research developing toward informatization.Network pharmacology,metabolism and cancer may be the focus of future research in this field.

An Introduction Effect Evaluation Tool for Distributed Generators

This paper presents practical distribution system equipment models such as various distributed generators, voltage regulators, and loads for fast three phase unbalanced load flow calculation in distribution systems. The method can calculate voltage and current of distribution systems, in which distributed generators are introduced. The calculation time of the proposed method is about 40 times faster than that of the Newton-Raphson method. Moreover, an introduction effect evaluation tool for distributed generators using the proposed three phase unbalanced load flow calculation is presented. It provides various functions such as a power system network diagram creation function and a voltage profile chart display function. Therefore, the introduction effect evaluation of distributed generators in distribution systems can be evaluated quite easily.

Market regulation and government intervention of vocational education＇s development

Government intervention and market regulation are two important ways in the process of economic operations, effective govemment intervention and market regulation can promote development of economic. This article briefly summarizes economists defined the government intervention and market regulation in the history of economic. Since the founding of New China, it elaborated to defining process of government intervention and market regulation in the development China＇ s economic. Under the new situation, it proposed government intervention should combine market regulation to achieve sound and fast development of economic. Market regulation in the development of vocational education for the economic development is the goal of training practical talents of vocational education. This objective requires that vocational education must work closely with the needs of economics＇ development and service for the economics＇ development. Under the system of planned economy, contraction between supply of talent and needs of economic is planning to achieve indirectly through a unified government.

Study of Comparative Saturated Sliding Mode Control and LQR Controller

The saturation problem is the one of the most common handicaps for applying to real applications, especially the actuator saturation. This paper focuses on the robustness of the sliding mode control （SMC） which incorporates a saturation constraint technique compared to classical linear quadratic regulator （LQR） with saturation. In the first step, the authors present a design methodology of SMC of a class of linear saturated systems. The authors present the structure of the saturation, after that the synthesis of the sliding surface is formulate as a problem of root clustering, which leads to the development of a continuous and non-linear control law that ensures the reaching condition of the sliding mode. The second step is devoted to present briefly the LQR controller technique. Finally, to validate results, the authors demonstrate an example of a quarter of vehicle system.

Stress Analysis and Shape Design of a Femoral Hip Prosthesis

Objective： To study the stress distribution of the femoral hip prosthesis after the hip joint replacement. Methods： After the hip joint replacement, when the fenmr and prosthesis are considered as concentric cylinders with perfectly banded interface, a relatively perfect theoretical model of simulating the interracial stress transfer is established. Results： The maximum interfaeial shear stress oeeured at Z=O. At the cross-section of the femoral neck, interfacial shear stress decreased exponentially with the increases of the Z. Shear stress became very small at Z〉0. 1 m, which meant that the shear stress at the far end of the femoral hip prosthesis was very small. In order to avoid the stress concentration and femoral hip prosthesis sinking, interracial stress must remain constant and balanced with the pressure load at Z=O. The radius of the femoral hip prosthesis changed with interfacial shear stress. The maximum value of the radius occured at Z=O, then it decreased at m. Specially, a=18.2 mm at Z=10 ram, a=5.36 mm at Z=98 ram, these are ideal radius. Conclusion： A theoretical model of simulating the interfacial stress is established when the femur and prosthesis are considered as concentric cylinders. The distributions of the interfacial shear and radial stresses with the axial positions are obtained. A theoretical reference for the design of the prosthesis is provided.

Satellite Simulator Control System Design Using SDRE Method

This paper presents the application of the State-Dependent Riccati Equation （SDRE） method in conjunction with Kalman filter technique to design a satellite simulator control system. The performance and robustness of the SDRE controller is compared with the Linear Quadratic Regulator （LQR） controller. The Kalman filter technique is incorporated to the SDRE method to address the presence of noise in the process, measurements and incomplete state estimation. The effects of the plant non-linearities and noises （uncertainties） are considered to investigated the controller performance and robustness designed by the SDRE plus Kalman filter. A general 3-D simulator Simulink model is developed to design the SDRE controller using the states estimated by the Kalman filter. Simulations have demonstrated the validity of the proposed approach to deal with nonlinear system. The SDRE controller has presented good stability, great performance and robustness at the same time that it keeps the simplicity of having constant gain which is very important as for satellite onboard computer implementation.

Design and Simulation of a Solar Regulator Based on DC-DC Converters Using a Robust Sliding ModeController

The MPPT （maximum power point tracking） is one of the most important features of a regulator system that processes the energy produced by a photovoltaic generator. It is necessary, in fact, to design a controller that is able to set the output value of the voltage and ensure the working within the maximum power point. In this paper, we propose the application of the robust sliding mode control technique to a DC-DC buck converter which is combined with a classical P ＆ O （perturbation and observation） algorithm to enhance the solar system efficiency. Dynamic equations describing the boost converter are derived and a sliding mode controller for a buck converter is designed. It is shown that, this control approach gives good results in terms of robustness toward load and input voltage variations. The effectiveness of the proposed work is verified by the simulation results under PowerSim environment.

刨煤机气动行程指示器

西德采矿研究股份公司在拉德鲍德(Radbod)矿试验了一种刨煤机用的压缩空气带动的行程指示器。这种仪器由两部分组成:一是在刨煤机齿轮箱的传动轴上安装的传感器;一是测量仪表。在传感器中(图中左侧)安有喷管系统,在喷管系统中间的痛形盘可旋转,扇形盘与传动轴相联。用固定在减速箱上的弹簧箍卡住传感器的外壳。

大力开展专利技术易货贸易

大力开展专利技术易货贸易刘永斌改革开放以来，我国易货贸易取得了较快发展，对活跃我国的内外贸易发挥了重要作用。当今世界易货贸易这一贸易形式正在迅速向其他领域扩展。专利技术“易货贸易”就是近几年迅速崛起的一种新的技术贸易形式。在我国正在发展的技术市场中，...