Impact performance for high frequency hydraulic rock drill drifter with sleeve valve

Guo, Yong,Yang, Shu Yi,Liu, De Shun,Zhang, Long Yan,Chen, Jian Wen Korean Society for Fluid machinery 2016 International journal of fluid machinery and syste Vol.9 No.1

A high frequency hydraulic rock drill drifter with sleeve valve is developed to use on arm of excavator. In order to ensure optimal working parameters of impact system for the new hydraulic rock drill drifter controlled by sleeve valve, the performance test system is built using the arm and the hydraulic source of excavator. The evaluation indexes are gained through measurement of working pressure, supply oil flow and stress wave. The relations of working parameters to impact system performance are analyzed. The result demonstrates that the maximum impact energy of the drill drifter is 98.34J with impact frequency of 71HZ. Optimal pressure of YZ45 rock drill is 12.8 MPa-13.6MPa, in which the energy efficiency reaches above 58.6%, and feature moment of energy distribution is more than 0.650.

Robust Design of Main Control Valve for Hydraulic Pile Hammer Flexible Control System

Guo, Yong,Hu, Jun Ping,Zhang, Long Yan Korean Society for Fluid machinery 2016 International journal of fluid machinery and syste Vol.9 No.1

The flexible control system for hydraulic pile hammer using main control valve is present to the requirement of rapidly reversing with high frequency. To ensure the working reliability of hydraulic pile hammer, the reversing performance of the main control valve should commutate robustness to various interfere factors. Through simulation model built in Simulink/Stateflow and experiment, the effects of relative parameters to reverse performance of main control are analyzed and the main interfere factors for reversing performance are acquired. Treating reverse required time as design objects, some structure parameters as control factors, control pressure, input flow and gaps between spool and valve body as interfere factors, the robust design of the main control valve is done. The combination of factors with the strongest anti-jamming capability is acquired which ensured the reliability and anti-jamming capability of the main control valve. It also provides guidance on design and application of the main control valve used in large flow control with interferes.

A meshfree adaptive procedure for shells in the sheet metal forming applications

Guo, Yong,Wu, C.T.,Park, C.K. Techno-Press 2013 Interaction and multiscale mechanics Vol.6 No.2

In this paper, a meshfree shell adaptive procedure is developed for the applications in the sheet metal forming simulation. The meshfree shell formulation is based on the first-order shear deformable shell theory and utilizes the degenerated continuum and updated Lagrangian approach for the nonlinear analysis. For the sheet metal forming simulation, an h-type adaptivity based on the meshfree background cells is considered and a geometric error indicator is adopted. The enriched nodes in adaptivity are added to the centroids of the adaptive cells and their shape functions are computed using a first-order generalized meshfree (GMF) convex approximation. The GMF convex approximation provides a smooth and non-negative shape function that vanishes at the boundary, thus the enriched nodes have no influence outside the adapted cells and only the shape functions within the adaptive cells need to be re-computed. Based on this concept, a multi-level refinement procedure is developed which does not require the constraint equations to enforce the compatibility. With this approach the adaptive solution maintains the order of meshfree approximation with least computational cost. Two numerical examples are presented to demonstrate the performance of the proposed method in the adaptive shell analysis.

Optimal Waveform Design for Ultra-Wideband Communication Based on Gaussian Derivatives

Guo, Yong The Korea Institute of Information and Commucation 2008 Journal of communications and networks Vol.10 No.4

Ultra-wideband (UWB) radios have attracted great interest for their potential application in short-range high-data-rate wireless communications. High received signal to noise ratio and compliance with the Federal Communications Commissions (FCC) spectral mask call for judicious design of UWB pulse shapers. In this paper, even and odd order derivatives of Gaussian pulse are used respectively as base waveforms to produce two synthesized pulses. Our method can realize high efficiency of spectral utilization in terms of normalized effective signal power (NESP). The waveform design problem can be converted into linear programming problem, which can be efficiently solved. The waveform based on even order derivatives is orthogonal to the one based on odd order derivatives.

A Novel Coverage Holes Discovery Algorithm Based on Voronoi Diagram in Wireless Sensor Networks

Guoyong Dai,Hexin Lv,Luyi Chen,Binbin Zhou,Ping Xu 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.3

Coverage is a key and fundamental problem in wireless sensor networks. To provide high quality of service, high coverage ratio of sensor nodes in monitored area should be assured. Coverage holes may lead to routing failure and degrade the quality of service. A novel coverage hole discovery algorithm, VCHDA, is proposed for wireless sensor networks in this paper. The proposed algorithm is based on the well-known Voronoi diagram. It can recognize coverage holes and label the border nodes of coverage holes effectively. Simulations are conducted and the results show that the proposed algorithm is effective and with high accuracy.

Spontaneous vesicle formation from trisiloxane-tailed gemini surfactant

Guoyong Wang,Zhiping Du,Dianlong Zhang,Ping Li 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.4

The spontaneous vesicle formation from a novel trisiloxane-tailed gemini surfactant were reported. The surface tension measurements revealed that aggregates are formed, and dynamic light scattering (DLS) measurements suggested the aggregates are vesicles. The size and morphology were observed by transmission electron microscopy (TEM). The vesicle formation was further confirmed by dye entrapment studies.

Polyglycerol modified polysiloxane surfactants: Their adsorption and aggregation behavior in aqueous solution

Guoyong Wang,Yanyan Zhu,Yunhui Zhai,Wanxu Wang,Zhiping Du,Jieqiong Qin 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.47 No.-

A simple process to synthesize polyglycerol modified polysiloxane surfactants has been carried outapplying a “grafting-to” approach. After formation of allyl polyglycerol ether (APGE) from diglycerol(DGY) and allyl glycidyl ether (AGE), polysiloxane modified by designed number of polyglycerol groups(PHMS-APGE) were obtained by connecting the APGE structure to different Si H functionalizedpolyhydromethyl siloxane (PHMS). The synthesized APGE-PHMS were characterized by IR and 1H NMR. Solubility measurements showed that the solubility of the as-prepared polymers increased in polarsolvents with the increasing of the amount of hydrophilic APGE groups. Furthermore, the surface activity,surface adsorption, aggregation and spreading behaviors of APGE-PHMS were investigated utilizingsurface tension measurements, dynamic light scattering (DLS), transmission electron microscopy (TEM)and contact angle measurements. The results showed that critical aggregation concentration (CAC) andthe time needed to reach adsorption equilibrium on water surface decrease systematically with theincrease in the number of APGE groups. These polymers in aqueous solutions could aggregate to formspherical assemblies. Moreover, the spreading behavior of these polymers on low energy surface wasfound to be influenced by the number of hydrophilic APGE groups.

Drainage procedure for pancreatolithiasis: re-examination of the pancreatic duct diameter standard

Guoyong Chen,Yu You,Hongxian Yan,Junchuang He,Jianping Gong,Sidong Wei 대한외과학회 2020 Annals of Surgical Treatment and Research(ASRT) Vol.98 No.4

Purpose: Pancreatic duct decompression relieves pancreatic duct stone (PDS)-associated abdominal pain, though a consensus indication for the drainage procedure of the main pancreatic duct (MPD) is lacking. Moreover, major prognostic factors for postsurgical long-term pain relief and recurrence are largely unknown. Methods: The clinical outcomes of 65 consecutive PDS patients undergoing surgery from 2008–2012 with 3+ years of follow-up were assessed. Results: At postsurgical follow-up (median, 4.5 years; range, 3–7 years; procedure: Partington, n = 32; Frey, n = 27; pancreatoduodenectomy, n = 3; distal pancreatectomy, n = 3), the early complication and complete stone clearance rates were 29.2% and 97%, respectively. Long-term, complete and partial pain relief were 93.9%, 83.1%, and 10.8%, respectively. The risk of pancreatic fistula was higher in the <8 mm group than in the >8 mm group (P < 0.05), and 80% of the pancreatic fistula cases occurred in the <8 mm group. A shorter pain duration (P = 0.007), smaller MPD diameter (P = 0.04), and lower Izbicki pain score (P < 0.001) predicted long-term pain relief. Pain recurrence after initial remission occurred in 5 patients and was only related to pain duration (P = 0.02). Stone recurrence and pancreatic exocrine functional and endocrine functional deterioration occurred in 2, 5, and 11 patients, respectively. Conclusion: Surgery provides excellent stone clearance, long-term pain relief, and acceptable postoperative morbidity. Using 8 mm as the criterion for drainage surgery can minimize the postoperative pancreatic fistula risk. Individualized and timely surgical treatment may improve the effect of surgery.

Research on Database Remote Disaster Recovery and Backup Technology Based on Multi Point and Multi Hop

Guoyong Lin,Fan Huang 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.6

Object: With the continuous advancement of information technology, more and more systems use database to store basic data, the security of data is an important part of the design of the business system. Method: In order to effectively improve the viability of data, this paper proposes a kind of multi point and multi hop database remote disaster recovery and backup technology. Process: Based on the in-depth analysis of the functions and demand of database, this paper introduces the working principles and key technologies of disaster recovery technology, describes the principles and realization process of multi point and multi hop database remote disaster recovery and backup technology, and carries on the experimental analysis. Conclusion: Theoretical analysis and experimental results show that this method is an effective new way of database remote disaster recovery and backup. So this technology has many advantages, such as multi point and multi hop backup, good real-time performance, fine backup granularity and so on.

Revisited Security Evaluation on Midori-64 against Differential Cryptanalysis

Guoyong Han,Hongluan Zhao 한국인터넷정보학회 2024 KSII Transactions on Internet and Information Syst Vol.18 No.2

In this paper, the Mixed Integer Linear Programming (MILP) model is improved for searching differential characteristics of block cipher Midori-64, and 4 search strategies of differential path are given. By using strategy IV, set 1 S-box on the top of the distinguisher to be active, and set 3 S-boxes at the bottom to be active and the difference to be the same, then we obtain a 5-round differential characteristics. Based on the distinguisher, we attack 12-round Midori-64 with data and time complexities of 263 and 2103.83, respectively. To our best knowledge, these results are superior to current ones.