Selection of Technical Routes for Resid Processing

With the increasing trend of heavy crudes supply with deteriorated quality and demand for clean fuels, deep processing of residuum, in particular the processing of low-grade resid, has become the main source for enhancing economic benefits of oil refiners. This article has discussed the technol- ogy for processing of different resids and the advantages and disadvantages of the combination pro- cesses for resid processing, while pinpointing the directions for development and application of tech- nologies for resid processing in China.

Prediction Model for Net Cutting Specific Energy in CNC Turning

A prediction model for net cutting specific energy in computer numerical control(CNC)turning based on turning parameters and tool wear is developed.The model can predict the net cutting energy consumption before turning.The prediction accuracy of the model is verified in AISI 1045 steel turning.The comparative experimental results show that the prediction accuracy of the model is significantly improved because the influence of tool wear is taken into account.Finally,the influences of turning parameters and tool wear on net cutting specific energy are studied.With the increase of cutting depth,the net cutting specific energy decreases.With the increase of spindle speed,the additional load loss power of spindle drive system increases,so the net cutting specific energy increases.The net cutting specific energy increases approximately linearly with tool wear.The results are helpful to formulate efficient and energy-saving CNC turning schemes and realize low‑carbon manufacturing.

Comprehensive Evaluation of Tahe Medium Gravity Crude

The comprehensive evaluation of Tahe medium gravity crude has demonstrated that this type of crude belongs to a intermediate base sour crude, featuring high vanadium content (103ppm), high carbon residue content, low pour point, and low acid value. Based on the crude processing conditions at SINOPEC Luoyang Petrochemical Branch Company, a proposal on the appropriate process flow scheme for processing Tahe crude oil has been raised with the main ideas presented as follows. The IBP-175 fraction is not an ideal feedstock for catalytic reforming; the 75-250 fraction is a qualified feedstock for zeolite de-waxing; the 140-230 fraction can be used to manufacture the No. 3 jet fuel through appropriate distillation range adjustment and product refining; the 175-350 fraction can be directly used to manufacture No.-10 diesel through proper refining; the atmospheric resid boiling over 350 is not suited to be used as the RFCC feedstock; the 350-520 vacuum distillate oil can be used as the FCC feedstock; and the vacuum residuum boiling over 520 is a good feedstock for manufacture of asphalt.

All Hydrogen Refinery with Zero Residue Discharge

This article summarizes the block process flow scheme for the 8.0 Mt/a refining project at Hainan Refining and Chemical Company, Ltd., highlighting a green route for processing sour heavy oils, and the enlarged scale of production with Chinese content. The refinery is targeted at hydrotreating of process streams, integration and intensified design of process units, clean gasoline and diesel production, centralized recovery and utilization of light ends and optimization of sulphur recovery systems.

Holographic storage scheme based on digital signal processing

In this paper, a holographic storage scheme for multimedia data storage and retrieval based on the digital signal processing (DSP) is designed. A communication model for holographic storage system is obtained on the analogy of traditional communication system. Many characteristics of holographic storage are embodied in the communication model. Then some new methods of DSP including two-dimensional (2-D) shifting interleaving, encoding and decoding of modulation-array (MA) code and method of soft-decision, etc. are proposed and employed in the system. From the results of experiments it can be seen that those measures can effectively reduce the influence of noise. A segment of multimedia data, including video and audio data, is retrieved successfully after holographic storage by using those techniques.

k-Nearest Neighbor Query Processing Algorithms for a Query Region in Road Networks

Recent development of wireless communication technologies and the popularity of smart phones .are making location-based services （LBS） popular. However, requesting queries to LBS servers with users＇ exact locations may threat the privacy of users. Therefore, there have been many researches on generating a cloaked query region for user privacy protection. Consequently, an efficient query processing algorithm for a query region is required. So, in this paper, we propose k-nearest neighbor query （k-NN） processing algorithms for a query region in road networks. To efficiently retrieve k-NN points of interest （POIs）, we make use of the Island index. We also propose a method that generates an adaptive Island index to improve the query processing performance and storage usage. Finally, we show by our performance analysis that our k-NN query processing algorithms outperform the existing k-Range Nearest Neighbor （kRNN） algorithm in terms of network expansion cost and query processing time.

Process-scheme-driven automatic construction of NC machining cell for aircraft structural parts

In order to enhance the NC programming efficiency and quality of aircraft structural parts （ASPs）, an intelligent NC programming pattern driven by process schemes is presented. In this pattern, the NC machining cell is the minimal organizational structure in the technological process, consisting of an operation machining volume cell, and the type and parameters of the machining operation. After the machining cell construction, the final NC program can be easily obtained in a CAD/CAM system by instantiating the machining operation for each machining cell. Accordingly, how to automatically establish the machining cells is a key issue in intelligent NC program- ming. On the basis of the NC machining craft of ASP, the paper aims to make an in-depth research on this issue. Firstly, some new terms about the residual volume and the machinable volume are defined, and then, the technological process is modeled with a process scheme. Secondly, the approach to building the machining cells is introduced, in which real-time complement machining is mainly considered to avoid interference and overcutting. Thirdly, the implementing algorithm is designed and applied to the Intelligent NC Programming System of ASP. Finally, the developed algorithm is validated through two case studies.