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Development of a Multi KD~* P Controller
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作者 Y.D.Park 1, U.W.Nam 1, Y. J.Moon 1, H.Y.Kim 2 1 (Korea Astronomy Observatory, Taejon 305 348, KOREA) 2 (Department of Space Science in Kyunghee University, Seoul 449 701, KOREA) 《天文研究与技术》 CSCD 1999年第S1期109-113,共5页
We have developed a new multi KD *P controller which enables us to control the high voltage input and three KD *Ps power supply simultanenously for the Solar Flare Telescope (SOFT) in Bohyunsan Optical Astronomy Obser... We have developed a new multi KD *P controller which enables us to control the high voltage input and three KD *Ps power supply simultanenously for the Solar Flare Telescope (SOFT) in Bohyunsan Optical Astronomy Observatory (BOAO). The new KD *P controller permits a very short switching time as well as a stable of electric power supply, making it possible to obtain multiple frames in a single phase of high voltage. Here we have used a 80C196KC microprocessor and three high voltage modules. The rising and falling time of output pulses generated from the new controller is found to be less than 10 -3 sec and the power supply stability is maintained within accuracy of less than 0 1%. The period of a single phase voltage is controlled by user in the range of 0 03sec to 3 seconds. The number of integrated image frames is also set by user up to 256 frames. The present system can be readily utilized to control a wider range of high voltage power by simply modifying software. 展开更多
关键词 Development of a Multi KD p controller
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Novel two-step process to improve efficiency of bio-oxidation of Axi high-sulfur refractory gold concentrates 被引量:2
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作者 刘新星 王国华 +4 位作者 霍强 谢建平 李寿朋 武海艳 郭玉洁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第12期4119-4125,共7页
In order to improve the bio-oxidation efficiency of Axi refractory gold concentrate, a two-step process including a high temperature chemical oxidation and a subsequent bio-oxidation, combined with p H control during ... In order to improve the bio-oxidation efficiency of Axi refractory gold concentrate, a two-step process including a high temperature chemical oxidation and a subsequent bio-oxidation, combined with p H control during the bio-oxidation step was used. The results revealed that the optimum mode was to maintain solution p H at 1.0-1.2 during the biological oxidation stage. Under this condition, the activity of mixed culture could be sustained and the formation of jarosite could be diminished, thus the oxidation efficiency was improved. The oxidation levels of iron and sulfur were improved by 12.50% and 15.49%, and the gold recovery was increased by 21.02%. Therefore, the two-step process combined with p H control is an effective method for oxidizing the biohydrometallurgical process of Axi gold concentrate, and it will have a broad prospect of application in dealing with complex refractory gold concentrate. 展开更多
关键词 gold concentrate BIO-OXIDATION p H control two-step oxidation
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Prognostic Value of P-gp and p27 in Patients with Esophageal Squamous Cell Carcinoma 被引量:4
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作者 倪型灏 许沈华 +3 位作者 施红旗 张谷 朱赤红 刘祥麟 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2007年第1期60-63,共4页
Objective: To evaluate the prognostic value of P-gp and p27 expression in patients with esophageal squamous cell carcinoma (ESC). Methods: The expressions of P-gp and p27 were detected by immunohistochemistry in 1... Objective: To evaluate the prognostic value of P-gp and p27 expression in patients with esophageal squamous cell carcinoma (ESC). Methods: The expressions of P-gp and p27 were detected by immunohistochemistry in 104 cases of ESC, and the clinicopathological characteristics were analyzed as well. Results: The positive rate of P-gp expression in 104 cases of ESCs was 32.7%. The positive rate of P-gp expression in the group that survived over 3 years (17.5%) was significantly lower than that in the group died within 3 years (53.3%) (x^2=14.227, P〈0.001). The positive rate of p27 expression in 104 cases of ESCs was 67.3%. The positive rate of p27 expression in the group that survived over 3 years (75.8%) was significantly higher than that in the group died within 3 years (56.5%) (x^2=4.361, P〈0.05). The patients with poorer differentiation whole wall invasion, lymph node metastasis and more advanced TNM stage had a shorter survival than did those with better differentiation, more superficial invasion, no lymph node involvement and earlier TNM stage; and it was statistically significant (P〈0.05). However, tumor size, macropathologic type, age and gender had no prognostic impact on ESC patients (P〉0.05). Conclusion: P-gp and p27 expression levels had a clinical prognostic significance in ESC. It could provide a reference basis for selecting the chemotherapy projection. The tumor differentiation degree, depth of invasion, lymph node involvement and TNM stages all were correlated to ESC patients' survival. 展开更多
关键词 Esophageal carcinoma p-glycoprotein p-gp Cyclin control factor p27) Immunohistochemistry prognosis
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Application of pH control to a tubular flow reactor
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作者 .Halil Vural Ayla Altinten +2 位作者 Hale Hapoglu Sebahat Erdogan Mustafa Alpbaz 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2015年第1期154-161,共8页
Tubular flow reactors are mainly used in chemical industry and waste water discharged units. Control of output variables is very difficult because of the existence of high dead-time in these types of reactors. In the ... Tubular flow reactors are mainly used in chemical industry and waste water discharged units. Control of output variables is very difficult because of the existence of high dead-time in these types of reactors. In the present work, sodium hydroxide and acetic acid solutions were sent to the tubular flow reactor. The aim was to control p H at 7 in the nonlinear region. The p H control of a tubular flow reactor with high time delay and a highly nonlinear behavior in p H neutralization reaction was investigated experimentally in the face of the various load and set point changes. Firstly, efficiency of conventional Proportional-Integral-Derivative(PID) algorithm in the experiments was tested. Then self-tuning PID(STPID) control system was applied by using the ARMAX model. The model parameters were calculated from input–output data by using PRBS signal as disturbance and Bierman algorithm. Lastly, the experimental fuzzy control of p H based on fuzzy model was achieved to compare the success of fuzzy approach with the performance of other control cases studied. 展开更多
关键词 Tubular flow reactor p H control Self tuning pID control pID control Fuzzy control
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Earth-observation satellite attitude control using passive and active hybrid magnetically suspended flywheels
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作者 杨照华 杨宁宁 余远金 《Journal of Beijing Institute of Technology》 EI CAS 2014年第2期226-234,共9页
The control strategy is presented using passive and active hybrid magnetically suspended flywheels(P&A MSFWs),which can help meet the requirements of high precision and high stability for earth-observation satellit... The control strategy is presented using passive and active hybrid magnetically suspended flywheels(P&A MSFWs),which can help meet the requirements of high precision and high stability for earth-observation satellites.Compared with the conventional flywheel,P&A MSFW has more rotation degrees of freedom(DOFs)since the rotor is suspended by magnetic bearings,and thus requires more efficient controllers.A modified sliding mode control law(SMC)to our novel nonlinear and coupled system is presented,which is interrupted by inertia matrix uncertainties and external disturbances.SMC law via Lyapunov method is improved,and a fuzzy control scheme is used to attenuate the chatting and control attitude accuracy and maintain the robustness of SMC.Simulation results are provided to illustrate the efficiency of our model by using our control law. 展开更多
关键词 attitude control passive and active hybrid magnetically suspended flywheels(p&A MSFWs) modeling and analyzing sliding mode control(SMC) fuzzy control
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A simple method of tuning series cascade controllers for unstable systems
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作者 Simi SANTOSH M.CHIDAMBARAM 《控制理论与应用(英文版)》 EI CSCD 2013年第4期661-667,共7页
A simple method is proposed to design P/PI controllers for a series cascade control system for unstable first order plus time-delay (FOPTD) systems. In this paper, the controller design for unstable FOPTD systems ca... A simple method is proposed to design P/PI controllers for a series cascade control system for unstable first order plus time-delay (FOPTD) systems. In this paper, the controller design for unstable FOPTD systems cascaded in series with stable/unstable FOPTD systems is considered. The proposed method is based on equating the coefficients of corresponding powers of s and s2 in the numerator to α1 and α2 times those of the denominator of the closed-loop transfer function for a servo problem. The open loop system consists of an unstable FOPTD system cascaded in series with a stable/unstable FOPTD system. Only two tuning parameters (α1 and α2) are required for the design of controllers. The closed-loop performances are evaluated for both the servo and regulatory problems and the performances are found to be better than that of the well established synthesis method. The robustness for uncertainty in the model parameters is studied and compared with that of the controllers designed by the synthesis method. 展开更多
关键词 Cascade control Time-delay process pI controller p controller FOpTD model Tuning
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Positive remediation on sedimentary P by combination of capping with calcium hydroxide and oxidation with perhydrol
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作者 Chutian Xu Wei Yue +6 位作者 Peirong Sun Shutong Chen Zhengying Wu Nan Xu Li Tang Guangzhou Sheng Dapeng Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2022年第2期170-179,共10页
The capping is called passive remediation because the sedimentary P was released and then immobilized by the capping materials.However,the release depends on the environmental conditions.Therefore,a hypothesis was pro... The capping is called passive remediation because the sedimentary P was released and then immobilized by the capping materials.However,the release depends on the environmental conditions.Therefore,a hypothesis was proposed that the oxidant was used to accelerate sedimentary P release and the capping material was used to capture those released P.It is positive remediation to reduce sedimentary P amount.The results show that soluble reactive phosphorus(SRP)concentration in the overlying water and pore water increased and then decreased gradually under the combination of sodium percarbonate(SPC)and Ca(OH)_(2),similar as that under the capping with single Ca(OH)_(2).The sedimentary P amount was reduced considerably and P concentration in the capping layer increased obviously after 60 days,compared with the capping with single Ca(OH)_(2).All these indicated that oxidation improved the sedimentary P release and the released P was captured and immobilized by the capping material of Ca(OH)_(2).However,the acceleration of sedimentary P release due to the oxidation is obviously different from the traditional mechanism that the oxic condition in the sediment is favor of the immobilization on sedimentary P.It is attributed to the oxidizability of?OH from SPC.The reduction of mobile-P and the increase of Ca-P under the combined use are observed.This is similar as traditional mechanism of oxic condition.It is sure that positive remediation reduced sedimentary P amount,resulting in the decrease of P release risk in a long time. 展开更多
关键词 REMEDIATION EUTROpHICATION Internal p control SEDIMENT
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Continuity Adjustment for Control Charts for Attributes
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作者 L.K.Chan T.K.Mak B.Tao 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2003年第3期397-404,共8页
A unified approach is proposed for making a continuity adjustment on some control charts for attributes, e.g., np-chart and c-chart, through adding a uniform (0, 1) random observation to the conventional sample statis... A unified approach is proposed for making a continuity adjustment on some control charts for attributes, e.g., np-chart and c-chart, through adding a uniform (0, 1) random observation to the conventional sample statistic (e.g., and c <SUB>i </SUB>). The adjusted sample statistic then has a continuous distribution. Consequently, given any Type I risk &#945; (the probability that the sample statistic is on or beyond the control limits), control charts achieving the exact value of &#945; can be readily constructed. Guidelines are given for when to use the continuity adjustment control chart, the conventional Shewhart control chart (with ±3 standard deviations control limits), and the control chart based on the exact distribution of the sample statistic before adjustment. 展开更多
关键词 Control charts for attributes continuity adjustments np p and c control charts statistical process control
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