Trajectory Distance Algorithm Based on Segment Transformation Distance

Longbao Wang,Xin Lv,Jicun An 한국인터넷정보학회 2022 KSII Transactions on Internet and Information Syst Vol.16 No.4

Along with the popularity of GPS system and smart cell phone, trajectories of pedestrians or vehicles are recorded at any time. The great amount of works had been carried out in order to discover traffic paradigms or other regular patterns buried in the huge trajectory dataset. The core of the mining algorithm is how to evaluate the similarity, that is, the “distance”, between trajectories appropriately, then the mining results will be accordance to the reality. Euclidean distance is commonly used in the lots of existed algorithms to measure the similarity, however, the trend of trajectories is usually ignored during the measurement. In this paper, a novel segment transform distance (STD) algorithm is proposed, in which a rule system of line segment transformation is established. The similarity of two-line segments is quantified by the cost of line segment transformation. Further, an improvement of STD, named ST-DTW, is advanced with the use of the traditional method dynamic time warping algorithm (DTW), accelerating the speed of calculating STD. The experimental results show that the error rate of ST-DTW algorithm is 53.97%, which is lower than that of the LCSS algorithm. Besides, all the weights of factors could be adjusted dynamically, making the algorithm suitable for various kinds of applications.

Research Status of DME Fuelled Diesel Engine in China

Zhou Longbao,Wang Ying,Wang Xibin,Pan Keyu,Jiang Deming 한국자동차공학회 2004 한국자동차공학회 Workshop Vol.2004 No.-

This paper mainly introduces the energy status, the necessity and importance of developing alternative fuel powered engine in China. DME is one of the most promising alternative fuels for diesel engine due to its excellent chemical and physical properties. Power output of DME engine can exceed that of the diesel engine. Emission results from ESC test cycles indicate that NOx.HC and PM emissions of CA498 DME engine all meet Euro Ⅲ regulation, excluding CO emission.

Photocatalytic Degradation Mechanism of Tetracycline by Ag@ZnO/C Core–Shell Plasmonic Photocatalyst Under Visible Light

Longbao Yu,Zhefei Ye,Jinze Li,Chunhong Ma,CHANGCHANG MA,XINLIN LIU,Huiqin Wang,Lili Tang,Pengwei Huo,Yongsheng Yan 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.6

A series of hamburger-like Ag@ZnO/C core–shell plasmonic photocatalysts have been synthesized via a simple solvothermal method for degradation of tetracycline (TC) under visible light irradiation, possessing high photocatalytic activity and good stability. The presence of localized surface plasmon resonance (LSPR) in the Ag core has increased the photocatalytic activity over an extended wavelength range. The plasmon-induced resonant energy transfer (PIRET) and direct electron transfer (DET) have facilitated the excitation and separation of photogenerated e-/h+pairs, which has been further confirmed by electrochemical investigations. The presences of hydroxyl radicals ( ·OH), superoxide radicals ( · O-2) and singlet oxygen (1O2) in the photocatalytic reaction system of Ag@ZnO/C photocatalyst have been demonstrated by electron spin resonance (ESR) measurements. All of the experiment results indicate that the ternary structure of Ag@ZnO/C can effectively enhance the photocatalytic activity. Furthermore, the effects of introduced Ag contents and carbon source dosage were researched by comparative photocatalytic experiments, and the potential structures of photodegradation products were studied by HPLC-MS.

Oxidation of cyclopentene catalyzed by phosphotungstic quaternary ammonium salt catalysts

Jinjuan Xue,Aili Wang,Jingbo Wang,Dongzhi Zhang,Weiguang Chen,Longbao Yu,Tingshun Jiang,Hengbo Yin 한국공업화학회 2010 Journal of Industrial and Engineering Chemistry Vol.16 No.2

A series of phosphotungstic quaternary ammonium salts, Q3 (PW12O40) and Q3(PW4O16) [Q = (C5H5)N+(C16H33), (C16H33)N+(CH3)3, (C4H9)4N+, and (CH3)4N+], were used as the catalysts in oxidation of cyclopentene. The catalysts [(C5H5)N(C16H33)]3(PW4O16) and [(C16H33)N(CH3)3]3(PW4O16) showed high catalytic activity in the selective oxidation of cyclopentene while using H2O2 (50%) as an oxidant and 2-propanol as a solvent. The oxidation products mainly consisted of glutaraldehyde, cis-1,2-cyclopentanediol and trans-1,2-cyclopentanediol. The above-mentioned two catalysts were dissolved completely in the reaction medium during the catalysis process and precipitated themselves from the reaction system after reaction, showing the characteristics of reaction-controlled phase-transfer catalysis. The types of quaternary ammonium cations and the phosphotungstic anions in phosphotungstic quaternary ammonium salts affected catalytic activity.

Delay-Bounded Associated Tasks Scheduling Based on Hierarchical Graph Model in the Cloud

Yingchi Mao,Haishing Zhong,Longbao Wang,Xiaofang Li 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.12

Cloud computing can provide the dynamic and elastic virtual resources for the users to execute the large-scale computing tasks. It has become the hot spot in the academic and industry fields. Task scheduling is one of the most important issues in the Cloud. In the Cloud systems, the goal of the tasks scheduling is to spread the workload among the computing nodes and maximize the utilization while the total execution time is within the specific delay bound. At present, almost scheduling algorithms focus on the single task dispatch in the Cloud. Unfortunately, there is little research on the associate tasks scheduling considering the deadline bound. In this paper, two hierarchical task models were discussed and the corresponding associated task scheduling algorithms based on delay-bound constraint (ATS-DB and SAH-DB) were proposed. The associated tasks and the task execution order were represented by one directed acyclic graph (DAG). The proposed hierarchical task models can improve the task execution concurrency. Extensive experimental results demonstrated that the proposed scheduling algorithms, ATS-DB and SAH-DB, can reduce the execution cost and improve the resource utilization within the user-expected delay bound.

Gas phase dehydration of glycerol catalyzed by rutile TiO_2-supported heteropolyacids

Lingqin Shen,Aili Wang,Hengbo Yin,Yonghai Feng,Longbao Yu,Tingshun Jiang,Yutang Shen,Zhanao Wu,박은덕 한국공업화학회 2011 Journal of Industrial and Engineering Chemistry Vol.17 No.3

Gas phase dehydration of glycerol catalyzed by the rutile TiO2-supported heteropolyacids was investigated. The TiO_2-supported heteropolyacid catalysts were prepared by the incipient wetness impregnation method using silicotungstic, phosphotungstic, and phosphomolybdic acids as active compounds. The as-prepared catalysts were characterized by X-ray diffraction, infrared spectroscopy,temperature programmed desorption of ammonia, and surface area measurement. The heteropolyacids supported by rutile TiO_2 were crystallites. The catalytic activity of the catalysts in the gas phase dehydration of glycerol was significantly affected by the type and loading of heteropolyacids. TiO_2-supported silicotungstic acid (20 wt.%) catalyst showed the highest catalytic activity with an acrolein selectivity of 80 mol% at a conversion of glycerol of 99% and a reaction temperature of 280 8C under ambient pressure. The possible reaction route in the gas phase dehydration of glycerol catalyzed by the TiO_2-supported heteropolyacid catalysts was also discussed briefly.

Acylation of salicylamide to 5-acetylsalicylamide using ionic liquids as dual catalyst and solvent

Weiguang Chen,Yunsheng Zhang,Zhangzhun Lu,Aili Wang,Yutang Shen,Tingshun Jiang,Longbao Yu,Hengbo Yin 한국공업화학회 2010 Journal of Industrial and Engineering Chemistry Vol.16 No.5

The Lewis acidic ionic liquids, 1-butyl-3-methylimidazolium chloroaluminate ([BMIM]Cl-nAlCl3) and Nbutylpyridinium chloroaluminate ([BPy]Cl-nAlCl3), were used as both catalyst and solvent in Friedel–Crafts acylation of salicylamide with acetyl chloride to 5-acetylsalicylamide. The Lewis acidic ionic liquids, substituting for the conventional carcinogenic nitrobenzene solvent and anhydrous AlCl3catalyst, showed excellent catalytic activity in the acylation of salicylamide to 5-acetylsalicylamide. When [BMIM]Cl-2AlCl3 was used as the catalyst, the yield of 5-acetylsalicylamide reached 81.3%. When [BPy]-2AlCl3 was used as the catalyst, the maximum yield of 5-acetylsalicylamide was 89.2%. The content of AlCl3 and the structure of the cations in the ionic liquids had synergistic effect on the acylation reaction. 2010 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

Apatite Formation on Anodized Ti-6Al-4V Alloy in Simulated Body Fluid

Xinyu Cui,김현민,Masakazu Kawashita,Longbao Wang,Tianying Xiong,Tadashi Kokubo,Takashi Nakamura 대한금속·재료학회 2010 METALS AND MATERIALS International Vol.16 No.3

Titania layers were successfully prepared on the surfaces of Ti-6Al-4V alloy via anodic oxidation in H2SO4or Na2SO4 solutions at room temperature. The titania layers consisted of pure rutile or a mixture of anatase and rutile structures after the Ti-6Al-4V alloy had been anodized in 1.0 M H2SO4 solution at 150 V or 0.5M Na2SO4 solution at 100 or 130 V. Good apatite-forming ability was demonstrated in simulated body fluid. However, surface layers with mainly titanium metallic phase or a pure anatase structure did not possess the ability to induce apatite formation. Anodic oxidation is an effective method to prepare bioactive Ti-6Al-4V alloy that can be used as an artificial bone substitute under load-bearing applications.

Synthesis of porous hollow silica spheres using functionalized polystyrene latex spheres as templates

Chun Liu,Hengbo Yin,Chen Ge,Aili Wang,Min Ren,Yunsheng Zhang,Longbao Yu,Tingshun Jiang 한국화학공학회 2011 Korean Journal of Chemical Engineering Vol.28 No.6

Uniform sized and integrated hollow silica spheres with porous shells were prepared by using sulfuric and carboxylic acid-functionalized polystyrene latex spheres as templates, sodium silicate as a precursor, and cetyltrimethylammonium bromide as a shell structure-directing agent. When polystyrene-methyl acrylic acid latex spheres were used as the templates, the pores in the shells of the resultant hollow silica spheres were composed of both micropores and mesopores. The pores in the shells of the hollow silica spheres were mainly composed of mesopores when sulfonated polystyrene-methyl acrylic acid latex spheres were used as the templates. The shell thickness and the specific surface area of the hollow silica spheres increased with the increase in the surface acidity of the latex spheres.