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DESIGN AND CONTROL OF A GRINDING ROBOT
Yong, Feng,Guo, Xu Dian,Yan, Wang 대한전자공학회 1992 HICEC:Harbin International Conference on Electroni Vol.1 No.1
This paper describes a grinding robot: HITDM-I, which is the fast grinding robot in our country. The grinding robot adopts teach-repeat operating mode. This paper mainly describes control system of the grinding robot, including the hardware and software.
Yong Feng,Haoxiang Wang,Min Zhang,Zihao Zhu,Xiaoyu Wang,Binhui Jia,Xiaolin Jia 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.21 No.5
Titanium Matrix Composites (TMCs) are widely used in aerospace because of their excellent mechanical properties, but itis accompanied by the diffi culty of machining. Ultrasonic Vibration Assisted Drilling (UVAD) can eff ectively reduce theaxial force in the drilling process and improve the integrity of machined surface. In this paper, the discontinuous titaniummatrix composite TiBw/TC4 was developed by preparation method of in situ. In order to obtain the machining parameters ofTiBw/TC4 and guide the application of UVAD in TiBw/TC4, the contrast experiments between conventional drilling (CD)and UVAD were carried out to analyze the variation law of axial force. In this experiment, the frequency and amplitude ofultrasonic vibration were set as 35 kHz and 2.5 μm respectively, and the drilling conditions were that the spindle speed was(1500/1600/1700/1800/1900) r/min and the feed speed was (6/7/8/9/10) mm/min. The surface integrity of hole wall suchas roughness, residual stress and white layer was discussed. The experimental results show that the yield strength of TiBw/TC4 developed by in situ is 51% higher than that of pure TC4. Compared with CD, the axial force of TiBw/TC4 in UVADis signifi cantly reduced, and the formation of continuous chips and winding cutters is eff ectively reduced. Besides, the wearrate of the cutters is reduced. The number and size of hole wall defects, such as scratches, delamination and tearing, areobviously reduced. As well as the residual stress, white layer thickness and hole wall roughness are reduced by 4.67–16.31%,42.48% and 5.98–29.27% respectively. Within the limits of the experiment, when the spindle speed is 1700 r/min and thefeed speed is 8 mm/min, UVAD can obtain better hole wall surface integrity parameters.
Application of Improved BP Neural Network with Correlation Rules in Network Intrusion Detection
Yongfeng Cui,Xiangqian Li Ma,Zhijie Liu 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.4
To detect various network attacks in real time, this paper developed a network intrusion detection system based on artificial neural network. This paper first introduced the recent development of neural network, BP algorithm and structure of a simple perceptron. Then, this paper developed an improved BP neural network algorithm to detect anomaly network traffic with adjusted correlation rules. Finally, the network intrusion system in this paper was tested in a real network situation; the improved BP algorithm neural network with adjusted correlation rules shows a reduction in total error and increment in alarm rate compared to the traditional basic BP algorithm model.
Analysis of structural dynamic reliability based on the probability density evolution method
Yongfeng Fang,Jianjun Chen,Kong Fah Tee 국제구조공학회 2013 Structural Engineering and Mechanics, An Int'l Jou Vol.45 No.2
A new dynamic reliability analysis of structure under repeated random loads is proposed in this paper. The proposed method is developed based on the idea that the probability density of several times random loads can be derived from the probability density of single-time random load. The reliability prediction models of structure based on time responses under several times random loads with and without strength degradation are obtained by using the stress-strength interference theory and probability density evolution method. The resulting differential equations in the prediction models can be solved by using the forward finite difference method. Then, the probability density functions of strength redundancy of the structures can be obtained. Finally, the structural dynamic reliability can be calculated using integral method. The efficiency of the proposed method is demonstrated numerically through a speed reducer. The results have shown that the proposed method is practicable, feasible and gives reasonably accurate prediction.
Yongfeng Fang,Wenliang Tao,Kong Fah Tee 국제구조공학회 2014 Smart Structures and Systems, An International Jou Vol.14 No.4
The model of unit dynamic reliability of repairable k/n (G) system with unit strengthdegradation under repeated random shocks has been developed according to the stress-strength interferencetheory. The unit failure number is obtained based on the unit failure probability which can be computed fromthe unit dynamic reliability. Then, the transfer probability function of the repairable k/n (G) system is givenby its Markov property. Once the transfer probability function has been obtained, the probability densitymatrix and the steady-state probabilities of the system can be retrieved. Finally, the dynamic reliability of therepairable k/n (G) system is obtained by solving the differential equations. It is illustrated that the proposedmethod is practicable, feasible and gives reasonable prediction which conforms to the engineering practice.
Repairable k-out-n system work model analysis from time response
Yongfeng Fang,Webliang Tao,Kong Fah Tee 사단법인 한국계산역학회 2013 Computers and Concrete, An International Journal Vol.12 No.6
A novel reliability-based work model of k/n (G) system has been developed. Unit failure probability is given based on the load and strength distributions and according to the stress-strength interference theory. Then a dynamic reliability prediction model of repairable k/n (G) system is established using probabilistic differential equations. The resulting differential equations are solved and the value of k can be determined precisely. The number of work unit k in repairable k/n (G) system is obtained precisely. The reliability of whole life cycle of repairable k/n (G) system can be predicted and guaranteed in the design period. Finally, it is illustrated that the proposed model is feasible and gives reasonable prediction.
Yongfeng Liu,Xiaowei Zhao,Manshun Liu,Jing Zhao 한국축산식품학회 2018 한국축산식품학회지 Vol.38 No.1
Cheese consumption has been gradually increased in China. However, both the manufacturing process of cheese and the utilization of its main by-product were not well developed. Based on the sensory evaluation, Box-Behnken Design (BBD) was performed in the present study to optimize the cheese processing, which was proved more suitable for Chinese. The optimal parameters were: rennet 0.052 g/L, start culture 0.025 g/L and CaCl2 0.1 g/L. The composition analysis of fresh bovine milk and whey showed that whey contained most of the soluble nutrients of milk, which indicated that whey was a potential resource of cyclic adenosine-3’, 5’-monophosphate (cAMP). Thus, the cAMP was isolated from whey, the results of high-performance liquid chromatography (HPLC) analysis showed that the macroporous adsorption resins (MAR) D290 could increase the concentration of cAMP from 0.058 μmol/mL to 0.095 μmol/mL. We firstly purified the cAMP from the whey, which could become a new source of cAMP.
( Yongfeng He ),( Hangun Kim ),( Taeyong Ryu ),( Youra Kang ),( Jeong Ae Kim ),( Bo Hyun Kim ),( Jae Hyuk Lee ),( Keonwook Kang ),( Qun Lu ),( Kwonseop Kim ) 영남대학교 약품개발연구소 2013 영남대학교 약품개발연구소 연구업적집 Vol.23 No.0
This study revealed that CWR22Rv-1 cells overexpressing δ-catenin display bigger tumor formation and higher angiogenic potentials than their matched control cells in the CAM assay. In addition, δ-catenin overexpression in CWR22Rv-1 cells results in increased hypoxia-inducible factor 1-alpha (HIF-1α and vascular endothelial growth factor (VEGF) expression. Furthermore, δ-catenin overexpression was found to enhance nuclear distribution of both β-catenin and HIF-1α in hypoxic condition, which is diminished by knockdown of δ-catenin. Our current study adds novel evidence regarding contribution of δ-catenin to the progression of prostate cancer. ⓒ2012 Federation of European Biochemical Societies. Published by Elsevier B.v.All rights reserved.
Research and Application of Intelligent Recommendation System Based on Big Data Technology
Yongfeng Cui,Yuankun Ma,Zhongyuan Zhao 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.8
With the rapid development of information technology and the Internet, people entered the era of information overload. Recommended system is an effective tool to solve the problem of information overload, it is based on the historical behavior of users and other records of interest to the user modeling, and then use the model to create user interest personalized recommendation, the interested user information, products. Online Intelligence is a new research direction, which integrates the latest achievements of artificial intelligence and information technology, greatly emphasizes on the Internet means intelligent application of data mining technology in the online intelligence research has a very important position. This paper presents a project-based collaborative filtering algorithm hierarchical similarity. Users to take advantage of some of the projects marked tags and project categories were automatically extended, to establish a hierarchy of all projects, and then use similar items tag hierarchy established between computing projects. Experimental results show that compared with traditional collaborative filtering algorithm, the ability of collaborative filtering algorithm based on similarity of item level can significantly improve the recommendation system to handle large data presented in this paper.