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Evaluation of the Impact of Refined Quality Control Management Model on the Qualified Rate of Disinfection and Sterilization of Surgical Instruments in the Sterilization Supply Center 被引量:1
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作者 Qin Liu 《Journal of Clinical and Nursing Research》 2024年第1期168-173,共6页
Objective:To evaluate the application value of a refined quality control management model for a sterilization supply center.Methods:A retrospective analysis was conducted on the work situation of the sterilization sup... Objective:To evaluate the application value of a refined quality control management model for a sterilization supply center.Methods:A retrospective analysis was conducted on the work situation of the sterilization supply center from January 2021 to January 2023.The work situation before January 31,2022,was classified as the control group;a routine quality control management model was implemented,and the work situation after January 31,2022,was classified as the observation group.The quality of medical device management and department satisfaction between the two groups were compared.Results:The timely recovery and supply rate,classification and cleaning pass rate,disinfection pass rate,packaging pass rate,sterilization pass rate,and department satisfaction score in the observation group were all higher than those of the control group(P<0.05).Conclusion:Implementing a refined quality control management model in the sterilization supply center can improve the quality management level of medical devices and department satisfaction and is worthy of promotion. 展开更多
关键词 Refined quality control management model Sterilization supply center Disinfection and sterilization pass rate
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考虑填充墙的RC框架结构性能指标限值确定方法 被引量:1
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作者 张令心 张明远 谢贤鑫 《工程力学》 EI CSCD 北大核心 2024年第7期109-120,共12页
填充墙钢筋混凝土(RC)框架结构是我国应用最为广泛的结构形式之一,而我国规范中给出的此类结构性能指标限值并未充分考虑填充墙对整体结构破坏状态的影响。遵循我国规范中对结构破坏状态的定义原则,提出基于构件破坏率的填充墙RC框架结... 填充墙钢筋混凝土(RC)框架结构是我国应用最为广泛的结构形式之一,而我国规范中给出的此类结构性能指标限值并未充分考虑填充墙对整体结构破坏状态的影响。遵循我国规范中对结构破坏状态的定义原则,提出基于构件破坏率的填充墙RC框架结构性能指标限值确定方法,为此类结构破坏状态与工程需求参数对应关系的研究提供新的思路。以典型结构为例建立数值分析模型,采用该文方法计算考虑填充墙的RC框架结构性能指标限值,并与不考虑填充墙的“纯框架”限值进行了对比分析。相较于“纯框架指标”,该文指标完好、轻微破坏、中等破坏和严重破坏四个破坏状态的层间位移角上限值均更小,其中,完好状态的上限值为1/832,远小于规范中规定的弹性层间位移角限值1/550,说明判定填充墙RC框架结构的破坏状态时,直接应用规范限值会低估结构的破坏程度。 展开更多
关键词 填充墙rc框架 数值分析 结构破坏状态 构件破坏率 性能指标限值
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Efficient Rate Control Algorithm for Hierarchical Video Coding
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作者 陆千里 岑锋 +1 位作者 许维胜 朱芳来 《Journal of Donghua University(English Edition)》 EI CAS 2012年第3期222-226,共5页
For rate control (RC) of hierarchical structure coding, an independent rate-quantization (R-Q) model was proposed based on mean absolute differences (MADs) in different temporal levels (TLs). In the proposed R-Q model... For rate control (RC) of hierarchical structure coding, an independent rate-quantization (R-Q) model was proposed based on mean absolute differences (MADs) in different temporal levels (TLs). In the proposed R-Q model, a novel MAD model was developed according to the hierarchical structure. The experimental results demonstrate that the proposed algorithm provides better performance, in terms of average peak signal-to-noise ratio (PSNR) and quality smoothness, than the H.264 reference model, JM14.2, under various sequences. 展开更多
关键词 rate-quantization (R-Q) model rate control(rc) video coding peak SIGNAL-TO-NOISE ratio (PSNR) HIERArcHICAL structure
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Cooperative Rate Splitting Transmit Design for Full-Duplex-Enabled Multiple Multicast Communication Systems
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作者 Siyi Duan Mingsheng Wei +2 位作者 Shidang Li Weiqiang Tan Bencheng Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期619-638,共20页
This paper examines the performance of Full-Duplex Cooperative Rate Splitting(FD-CRS)with Simultaneous Wireless Information and Power Transfer(SWIPT)support in Multiple Input Single Output(MISO)networks.In a Rate Spli... This paper examines the performance of Full-Duplex Cooperative Rate Splitting(FD-CRS)with Simultaneous Wireless Information and Power Transfer(SWIPT)support in Multiple Input Single Output(MISO)networks.In a Rate Splitting Multiple Access(RSMA)multicast system with two local users and one remote user,the common data stream contains the needs of all users,and all users can decode the common data stream.Therefore,each user can receive some information that other users need,and local users with better channel conditions can use this information to further enhance the reception reliability and data rate of users with poor channel quality.Even using Cell-Center-Users(CCUs)as a cooperative relay to assist the transmission of common data can improve the average system speed.To maximize the minimum achievable rate,we optimize the beamforming vector of Base Station(BS),the common streamsplitting vector,the cooperative distributed beamvector and the strong user transmission power under the power budget constraints of BS and relay devices and the service quality requirements constraints of users.Since the whole problem is not convex,we cannot solve it directly.Therefore,we propose a low complexity algorithm based on Successive Convex Approximation(SCA)technology to find the optimal solution to the problemunder consideration.The simulation results show that FD C-RSMA has better gain andmore powerful than FD C-NOMA,HD C-RSMA,RSMA and NOMA. 展开更多
关键词 Full-duplex cooperative rate segmentation SWIPT RSMA power control
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Screening, Treatment and Control of High Blood Pressure on Five Sites in Mali
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作者 Mamadou Touré Sagara Ibrahima +19 位作者 Youssouf Camara Hamidou Oumar Bâ Ibrahima Sangaré Djénébou Traoré Noumou Sidibé Fousseyni Samassékou Massama Konaté Coumba Thiam Doumbia Asmaou Maiga Réné-Marie Dakouo Hamidou Camara Sako Mariam Sidibé Samba Adama Sogodogo Boubacar Diarra Boubacar Sonfo Aladji Traoré Mamadou Diakité Ilo Bella Diall Ichaka Menta 《World Journal of Cardiovascular Diseases》 CAS 2024年第5期322-332,共11页
Introduction: High blood pressure is defined as blood pressure greater than or equal to 140 mm Hg for systolic and or 90 mm Hg for diastolic. It constitutes a major public health problem, the leading chronic disease i... Introduction: High blood pressure is defined as blood pressure greater than or equal to 140 mm Hg for systolic and or 90 mm Hg for diastolic. It constitutes a major public health problem, the leading chronic disease in the world. The objective was to determine the prevalence, treatment rate and control of hypertension. Methods: This was a cross-sectional and descriptive study which took place over a period of 6 months in a hospital environment and in the general population. Results: Of the 1000 participants, 637 had hypertension, giving a prevalence of 63.70% with a female predominance. Thirty-three percent (33%) were unaware of their high blood pressure. The age group 60 and more was the most represented (44%). A proportion of 33 and 23.20 were overweight and obese participants, respectively. Male subjects were more overweight than female, unlike obesity which was more common among female subjects. Sixty-two percent (62%) of hypertensives were treated, of whom 44% were non-compliant. The excessively high cost and consumption of medications as needed were the main factors in therapeutic non-compliance. Twenty-two percent (22%) of all hypertensive patients and 35% of treated hypertensive patients were controlled. Women were more treated but less observant and less controlled than men. Therapeutic coverage and combination therapy rates were lower in rural areas. Hypertensives who had a high level of education were better treated and controlled than those who had no level. Conclusion: High blood pressure remains a real public health problem in Mali. It is more common in people aged 60 and over and in females. One in three hypertensives were unaware of their hypertension. The majority received antihypertensive treatments, but only a minority of them had their hypertension controlled. 展开更多
关键词 High Blood Pressure SCREENING control rate MALI
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Remote Control of Bovine Catalase Activity with Specific Frequencies of Human and Bovine Catalase with and without Bound NADP+
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作者 Thibaud Etienne d’Oultremont 《Advances in Enzyme Research》 CAS 2024年第2期17-34,共18页
Remote control enzyme technology is widely used today through resonance. In this study, we showed that the use of frequencies of the catalase enzyme itself to increase enzymatic rate is successful not only in test tub... Remote control enzyme technology is widely used today through resonance. In this study, we showed that the use of frequencies of the catalase enzyme itself to increase enzymatic rate is successful not only in test tubes but also remotely. The present study also suggests that, under optimal temperature, the use of bovine catalase frequency (the specific frequency of that enzyme) has a superior rate promoting vibration than the human catalase frequency, and so increases very significantly the chemical rate of bovine catalase (about 120% at 40˚C). It also suggests that bovine catalase subjected to bovine and human frequencies with catalase bound NADP+ experienced more resonance weight towards NADP+ and so were more slowly reduced back to catalase bound NADPH, increasing compound II formation rate, and slowing down the catalase activity rate. 展开更多
关键词 Remote control CATALASE Frequency rate Promoting Vibration (RPV) NADP
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Optimal source rate control for adapting VBR video over CBR channels
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作者 Chunwen LI Peng ZHU 《控制理论与应用(英文版)》 EI 2006年第2期111-113,共3页
In this paper we discuss the source rate control problem of adapting variable bit-rate (VBR) compressed video over constant bit-rate (CBR) channels. Firstly we formulate it as an optimal control problem of a discr... In this paper we discuss the source rate control problem of adapting variable bit-rate (VBR) compressed video over constant bit-rate (CBR) channels. Firstly we formulate it as an optimal control problem of a discrete linear system with state and control constraints. Then we apply the discrete maximum principle to get the optimal solution. Experimental results are given in the end. Compared with traditional algorithms, the proposed algorithm is suitable for the coder with continuous output rates, and can achieve the better solution. Our algorithm can be used in both off-line and on-line coding. 展开更多
关键词 Optimal control rate control VBR video CBR channel
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Reducing the Error Rate of Drug Delivery in Hospital Pharmacies: From the Angle of Pharmacy Quality Control Circle 被引量:1
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作者 Wang Shuling Chen Hui +1 位作者 De Xianhui Liu Linchuan 《Asian Journal of Social Pharmacy》 2019年第2期66-76,共11页
Objective To explore the effect of applying pharmacy quality control circle to reduce the error rate of drug delivery in inpatient pharmacy,and to improve the service quality of inpatient pharmacy staff.Methods Accord... Objective To explore the effect of applying pharmacy quality control circle to reduce the error rate of drug delivery in inpatient pharmacy,and to improve the service quality of inpatient pharmacy staff.Methods According to the ten standardized steps of pharmaceutical product management and Gantt chart,fishbone diagram and Plato were used to analyze the causes of drug delivery errors in hospital pharmacies,to find countermeasures and confirm the implementation effect.Results and Conclusion The error rate was reduced from 52% before implementation to 27.8%,and the target achievement rate was 100%.The staff’s understanding and application ability of pharmaceutical product circle was further enhanced.The “Training Standard for Newcomers” has reference value for hospital inpatient pharmacies and it can be promoted continuously.Pharmaceutical quality control circle can improve the quality of pharmacy services in hospitals. 展开更多
关键词 quality control circle INPATIENT PHARMACY DRUG ERROR rate
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Research on the Three-phase Photovoltaic Grid-connected Control Strategy
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作者 Yukai Liu Zhijian Hu +2 位作者 Ziyong Zhang Jianglei Suo Kaibin Liang 《Energy and Power Engineering》 2013年第4期31-35,共5页
This paper mainly studies scheduling type photovoltaic generation system, and establishes a three-phase photovoltaic grid-connected model in Matlab/Simulink, which uses the MPPT control that can make full use of the s... This paper mainly studies scheduling type photovoltaic generation system, and establishes a three-phase photovoltaic grid-connected model in Matlab/Simulink, which uses the MPPT control that can make full use of the solar energy. At the same time, energy storage device is added. The inverter of the energy storage device adopts V/f control. In the running state of the islanding because of a certain power failure, it can maintain a constant voltage and frequency. The simulation shows that as the output of the photovoltaic power increases, harmonic rate decreases under the same conditions, and the energy storage device can increase the stability of photovoltaic grid and reduce harmonic contents. So it’s very necessary to add energy storage device in the photovoltaic system. 展开更多
关键词 PHOTOVOLTAIC Grid Energy Storage Device PQ control V/F control HARMONIC rate
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Reducing the Internal Difference Error Rate in Hospital Pharmacies:From the Angle of Quality Control Circle 被引量:1
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作者 Wang Shuling Lei Yingzi +2 位作者 Liu Linchuan Wang Ruili He Yalan 《Asian Journal of Social Pharmacy》 2020年第2期73-82,共10页
Objective To improve the management level of pharmacy dispensing center,reduce dispensing errors and promote the safety of drug use.Methods Hospital pharmacies could be managed according to the theory of quality contr... Objective To improve the management level of pharmacy dispensing center,reduce dispensing errors and promote the safety of drug use.Methods Hospital pharmacies could be managed according to the theory of quality control circle(QCC).Based on the ten steps of QCC,the internal difference error rate in pharmacies could be reduced.Results and Conclusion The error rate of pharmacies was reduced from 2.74‰to 0.57‰,and the goal achievement rate was 108.466.Besides,the progress rate reached 84.82%.The abilities of circle members were improved,and the operation of pharmacy was more standardized.The activity of QCC is helpful to reduce the internal difference error rate,improve the operation level of pharmacy and ensure the safety of drug use. 展开更多
关键词 quality control circle(QCC) medical institution internal difference error rate
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基于RCA的路径式质控管理对消毒供应室灭菌合格率、管理质量和感染率的影响
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作者 陈萍茹 林彬红 陈玲娇 《中外医学研究》 2024年第18期156-159,共4页
目的:探究基于根本原因分析(RCA)的路径式质控管理对消毒供应室灭菌合格率、管理质量和感染率的影响。方法:以2021年7月中国人民解放军联勤保障部队第九一〇医院消毒供应室实施基于RCA的路径式质控管理干预为分界线,将2020年1月—2021年... 目的:探究基于根本原因分析(RCA)的路径式质控管理对消毒供应室灭菌合格率、管理质量和感染率的影响。方法:以2021年7月中国人民解放军联勤保障部队第九一〇医院消毒供应室实施基于RCA的路径式质控管理干预为分界线,将2020年1月—2021年6月实施常规消毒灭菌管理的86组手术器械纳为管理前组,将2021年7月—2022年12月实施基于RCA的路径式质控管理的86组手术器械纳为管理后组。观察两组灭菌合格率[目测法、蛋白质残留检测、三磷酸腺苷(ATP)荧光检测、细菌菌落检测]、管理质量(器械管理、医疗垃圾处理、手卫生管理、技能考核培训)、器械相关感染发生率、临床科室及手术室人员对消毒供应中心服务满意度。结果:管理后组目测法、蛋白质残留检测、ATP荧光检测、细菌菌落检测合格率高于管理前组,差异有统计学意义(P<0.05);管理后组器械管理、医疗垃圾处理、手卫生管理、技能考核培训评分高于管理前组,差异有统计学意义(P<0.05);管理后组器械相关感染发生率为3.49%,低于管理前组的12.79%,差异有统计学意义(P<0.05);管理后组服务态度、物品质量、物品交接、器械配送、信息追溯满意度高于管理前组,差异有统计学意义(P<0.05)。结论:基于RCA的路径式质控管理可改善消毒供应中心的灭菌合格率,提升器械管理质量,降低院内器械相关感染率,且临床科室及手术室人员较满意。 展开更多
关键词 根本原因分析 路径式质控管理 消毒供应室 灭菌合格率 管理质量 感染率
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A rate control approach to distributed source coding for interferential multispectral image compression
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作者 宋娟 Li Yunsong Wu Chengke Wang Yangli 《High Technology Letters》 EI CAS 2010年第2期133-137,共5页
Distributed source coding (DSC) is applied to interferential multispectral image compression owing to strong correlation among the image frames. Many DSC systems in the literature use feedback channel (FC) to cont... Distributed source coding (DSC) is applied to interferential multispectral image compression owing to strong correlation among the image frames. Many DSC systems in the literature use feedback channel (FC) to control rate at the decoder, which limits the application of DSC. Upon an analysis of the image data, a rate control approach is proposed to avoid FC. Low-complexity motion compensation is applied first to estimate side information at the encoder. Using a polynomial fitting method, a new mathematical model is then derived to estimate rate based on the correlation between the source and side information. The experimental results show that our estimated rate is a good approximation to the actual rate required by FC while incurring a little bit-rate overhead. Our compression scheme performs comparable with the FC based DSC system and outperforms JPEG2000 significantly. 展开更多
关键词 interferential multispectral image distributed source coding (DSC) rate control motion compensation polynomial fitting
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基于双线性ADRC的翼伞系统三维航迹跟踪控制
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作者 周宇阳 赵敏 +1 位作者 王成 齐贺轩 《机械制造与自动化》 2024年第1期255-259,共5页
目前翼伞系统的航迹跟踪主要针对二维路径,对于三维航迹跟踪的研究不多。针对翼伞系统6-DOF模型,采用具有天然解耦属性的自抗扰控制策略,设计一种基于双线性ADRC(B-ADRC)的三维轨迹跟踪控制方法。在水平面与纵向设计制导率与控制器,实... 目前翼伞系统的航迹跟踪主要针对二维路径,对于三维航迹跟踪的研究不多。针对翼伞系统6-DOF模型,采用具有天然解耦属性的自抗扰控制策略,设计一种基于双线性ADRC(B-ADRC)的三维轨迹跟踪控制方法。在水平面与纵向设计制导率与控制器,实现姿态与轨迹位置的跟踪,并对轨迹跟踪误差进行实时修正。跟踪过程中,将理想轨迹离散化获得一系列参考点,通过点切换的方式实现了复杂轨迹的跟踪。实验结果表明:所设计的双线性ADRC控制器能够实现对三维航迹的跟踪,具有良好的鲁棒性和抗干扰能力。 展开更多
关键词 翼伞系统 6-DOF模型 三维航迹跟踪控制 制导率 B-ADrc控制器
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含RC滤波电路的多通道复用模拟信号采集时序研究
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作者 沈威 钱波 樊红星 《机械工程与自动化》 2024年第2期37-38,41,共3页
针对嵌入式控制系统中含RC滤波电路的多通道复用模拟信号采集不准确问题,选用了一种通用的硬件电路,从软件时序的角度出发,制定了多组测试方案,研究得出一种数据采集准确度高、稳定性好的通用软件采集时序。
关键词 嵌入式控制系统 rc滤波 信号采集
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Factors related to lymph node metastasis and surgical strategy used to treat early gastric carcinoma 被引量:68
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作者 Dong Yi Kim Jae Kyoon Joo +2 位作者 Seong Yeob Ryu Young Jin Kim Shin Kon Kim 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第5期737-740,共4页
AIM:The prognosis of early gastric carcinoma (EGC) is generally excellent after surgery. The presence or absence of lymph node metastasis in EGC is an important prognostic factor. The survival and recurrence rates of ... AIM:The prognosis of early gastric carcinoma (EGC) is generally excellent after surgery. The presence or absence of lymph node metastasis in EGC is an important prognostic factor. The survival and recurrence rates of node-negative EGC are much better than those of node-positive EGC. This study examined the factors related to lymph node metastasis in EGC to determine the appropriate treatment for EGC.METHODS: We investigated 748 patients with EGC who underwent surgery between January 1985 and December 1999 at the Division of Gastroenterologic Surgery, Department of Surgery, Chonnam National University Hospital. Several clinicopathologic factors were investigated to analyze their relationship to lymph node metastasis: age, sex, tumor location, tumor size, gross type, histologic type, depth of invasion, extent of lymph node dissection, type of operation,and DNA ploidy.RESULTS:Lymph node metastases were found in 75 patients (10.0%). Univariate analysis showed that male sex, tumor size larger than 2.0cm, submucosal invasion of tumor, histologic differentiation, and DNA ploidy pattern were risk factors for regional lymph node metastasis in EGC patients. However, a multivariate analysis showed that three risk factors were associated with lymph node metastasis:large tumor size, undifferentiated histologic type and submucosal invasion. No statistical relationship was found for age, sex, tumor location, gross type, or DNA ploidy in multivariate analysis. The 5-year survival rate was 94.2% for those without lymph node metastasis and 87.3% for those with lymph node metastasis, and the difference was significant (P<0.05).CONCLUSION: In patients with EGC, the survival rate of patients with positive lymph nodes is significantly worse than that of patients with no lymph node metastasis. Therefore,a standard D2 lymphadenectomy should be performed in patients at high risk of lymph node metastasis: large tumor size, undifferentiated histologic type and submucosal invasion. 展开更多
关键词 Stomach Neoplasms ADULT Cell Differentiation FEMALE Humans Logistic Models Lymph Node Excision Lymphatic Metastasis control Male Risk Factors Survival rate
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A rate control scheme for H.264 video under low bandwidth channel 被引量:11
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作者 YIN Ming WANG Hong-yuan 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第6期990-995,共6页
The dilemma of the quantization parameter (QP) being involved in both rate control and rate-distortion optimization (RDO) prevents using the traditional rate control scheme. Although some rate control schemes are prop... The dilemma of the quantization parameter (QP) being involved in both rate control and rate-distortion optimization (RDO) prevents using the traditional rate control scheme. Although some rate control schemes are proposed to circumvent the dilemma, the inaccurate prediction model and improper bit allocation deter H.264 application on low bandwidth channel. To resolve this issue, this paper proposes a novel rate control scheme by considering the macroblock (MB) encoding complexity variation and buffer variation and by exploiting the spatio-temporal correlation sufficiently well. Simulations showed that this scheme improves the perceptual quality of the pictures with similar or smaller PSNR deviations when compared to that of rate control in JVT-O016. 展开更多
关键词 Video coding H.264 rate control HRD Bit allocation
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Aircraft Electric Anti-skid Braking System Based on Fuzzy-PID Controller with Parameter Self-adjustment Feature 被引量:4
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作者 魏小辉 尹乔之 +2 位作者 聂宏 张明 陶周亮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2014年第1期111-118,共8页
The principle of electric braking system is analyzed and an anti-skid braking system based on the slip rate control is proposed.The fuzzy-PID controller with parameter self-adjustment feature is designed for the anti-... The principle of electric braking system is analyzed and an anti-skid braking system based on the slip rate control is proposed.The fuzzy-PID controller with parameter self-adjustment feature is designed for the anti-skid braking system.The dynamic model of aircraft ground braking is established in the simulation environment of MATLAB/SIMULINK,and simulation results of dry runway and wet runway are presented.The results show that the fuzzy-PID controller with parameter self-adjustment feature for the electric anti-skid braking system keeps working in the state of stability and the brake efficiencies are increased to 93%on dry runway and 82%on wet runway respectively. 展开更多
关键词 electric braking system slip rate anti-skid braking fuzzy-PID controller
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Effect of mixing rate and temperature on primary Si phase of hypereutectic Al-20Si alloy during control ed diffusion solidification(CDS) process 被引量:5
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作者 Yuan-dong Li Xin-long Zhang +3 位作者 Ying Ma Diran Apelian Hong-wei Zhou Xing-hai Liu 《China Foundry》 SCIE CAS 2015年第3期173-179,共7页
Controlled Diffusion Solidification(CDS) is a promising process relied on mixing two liquid alloys of precisely controlled chemistry and temperature in order to produce a predetermined alloy composition. In this study... Controlled Diffusion Solidification(CDS) is a promising process relied on mixing two liquid alloys of precisely controlled chemistry and temperature in order to produce a predetermined alloy composition. In this study, the CDS was employed to prepare hypereutectic Al-20%Si(mass fraction) alloy using Al-30%Si and pure Al of different temperatures. The mixing rate was controlled using three small crucibles with a hole of different diameters in their bottom. The effect of mixing rate and temperature on the microstructure of the primary Si-phase during the mixing of molten Al and Al-30%Si was studied. The results showed that when the diameter of the small crucible bottom hole is 16 mm, a higher mass mixing rate 0.217 kg·s-1 would results in a lower stream velocity 0.414 m·s-1. Conversely a lower mass mixing rate 0.114 kg·s-1(the diameter of the small crucible bottom hole is 8 mm) would result in a higher fluid stream velocity 0.879 m·s-1. A lower mass mixing rate would be better to refine the primary Si than a higher mass mixing rate. Meanwhile, the morphology and distribution of primary Si could also be improved. Especially, when Al-30%Si alloy at 820 °C was mixed with pure Al at 670 °C in the case of a mass mixing rate of 0.114 kg·s-1 and a pouring temperature of 680 °C, the average size of the primary Si phase would be only 18.2 μm. Its morphology would mostly be octahedral and the primary Si would distribute uniformly in the matrix microstructure. The lower mass mixing rate(0.114 kg·s-1) will enhance the broken tendency of Al-30%Si steam and the mixing agitation of resultant melt, so the primary Si phase can be better refined. 展开更多
关键词 controlled Diffusion Solidification(CDS) hypereutectic Al-Si alloy mass mixing rate stream velocity primary Si
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Active disturbance rejected predictive functional control for space vehicles with RCS 被引量:3
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作者 TIAN Jiayi ZHANG Shifeng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第5期1022-1035,共14页
Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitab... Reaction control system(RCS) is a powerful and efficient actuator for space vehicles attitude control, which is typically characterized as a pulsed unilateral effector only with two states(off/on). Along with inevitable internal uncertainties and external disturbances in practice, this inherent nonlinear character always hinders space vehicles autopilot from pursuing precise tracking performance. Compared to most of pre-existing methodologies that passively suppress the uncertainties and disturbances, a design based on predictive functional control(PFC) and generalized extended state observer(GESO) is firstly proposed for three-axis RCS control system to actively reject that with no requirement for additional fuel consumption. To obtain a high fidelity predictive model on which the performance of PFC greatly depends, the nonlinear coupling multiple-input multiple-output(MIMO) flight dynamics model is parameterized as a state-dependent coefficient form. And based on that, a MIMO PFC algorithm in state space domain for a plant of arbitrary orders is deduced in this paper.The internal uncertainties and external disturbances are lumped as a total disturbance, which is estimated and cancelled timely to further enhance the robustness. The continuous control command synthesised by above controller-rejector tandem is finally modulated by pulse width pulse frequency modulator(PWPF) to on-off signals to meet RCS requirement. The robustness and feasibility of the proposed design are validated by a series of performance comparison simulations with some prominent methods in the presence of significant perturbations and disturbances, as well as measurement noise. 展开更多
关键词 reaction control system(rcS) predictive functional control(PFC) generalized extended state observer(GESO) pulse width pulse frequency(PWPF) multiple-input multiple-output(MIMO)
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An efficient rate control algorithm for JPEG2000 based on reverse order 被引量:1
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作者 A.Etesaminia A.H.Mazinan 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1396-1405,共10页
The JPEG2000 image compression standard is the powerful encoder which can provide phenomenal rate-control performance. The post-compression rate-distortion(PCRD) algorithm in JPEG2000 is not efficient. It requires enc... The JPEG2000 image compression standard is the powerful encoder which can provide phenomenal rate-control performance. The post-compression rate-distortion(PCRD) algorithm in JPEG2000 is not efficient. It requires encoding all coding passes even though a large contribution of them will not be contained in the final code-stream. Tier-1 encoding in the JPEG2000 standard takes a significant amount of memory and coding time. In this work, a low-complexity rate distortion method for JPEG2000 is proposed. It is relied on a reverse order for the resolution levels and the coding passes. The proposed algorithm encodes only the coding passes contained in the final code-stream and it does not need any post compression rate control part. The computational complexity of proposed algorithm is negligible, making it suitable to compression and attaining a significant performance. Simulations results show that the proposed algorithm obtained the PSNR values are comparable with the optimal PCRD. 展开更多
关键词 image CODING JPEG2000 POST compression rate DISTORTION (PCRD) rate control
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