Mathematical programming model of process plant safety layout using the equipment vulnerability index

Liping Guo,Zhirong Wang,Pinkun Guo,Jinghong Wang,Dan Zhao 한국화학공학회 2023 Korean Journal of Chemical Engineering Vol.40 No.4

Safety is the focus of attention in plant layout problems. Previous studies have often expressed safety as a cost of risk, that is, the cost of property losses that may occur in an accident. In this paper, the influence of uncertainty on the equipment vulnerability is quantitatively considered and a more reliable process plant layout is proposed. The equipment vulnerability index is used to evaluate the vulnerability level of the target equipment in case of an accident, which is applied to propose a mixed-integer nonlinear optimized process plant layout to minimize domino risk. In addition, a decision matrix is applied to determine whether the risk level of the optimized layout of the target equipment is acceptable. Damage probability and vulnerability are the basic inputs of this matrix. The proposed method was applied to a coal-water slurry gasification process and the results show that the layout obtained by the proposed model has better practical value than the current layout, reducing the domino risk by 53.2%. Meanwhile, the model can be used to identify critical equipment and select targeted safety measures during the production stage.

Ultrasonically Carbon Coated Si Nanoparticles for Lithium Ion Batteries

Guo, Liping,Lee, Hyunju,Kim, Donghwan,Yoon, Wooyoung American Scientific Publishers 2012 Journal of nanoscience and nanotechnology Vol.12 No.2

Fabrication and Characterization of a Silicon-Carbon Nanocomposite Material by Pyrolysis for Lithium Secondary Batteries

Liping Guo,윤우영,Bok Ki Kim 대한금속·재료학회 2012 ELECTRONIC MATERIALS LETTERS Vol.8 No.4

This paper presents the fabrication and testing results of a Silicon-Carbon nanocomposite material used for lithium secondary batteries which was prepared through the pyrolysis of alginic acid which was utilized as the carbon source. Silicon nanoparticles were mixed with alginic acid which was first dissolved in a Na2CO3solution. After drying, the blend was ground into powders and heated in an argon atmosphere. Based on Raman spectra, the ordering of the carbon from the decomposition of the carbon source was clearly distinguished. The reversible specific discharge capacity of silicon in the electrode of this composite material was as high as 1928 mAhg−1, which indicates excellent cycling stability.

A New Semi-supervised Classification Method of Hyperspectral Image based on Combining Renyi Entropy and Multinomial Logistic Regression Algorithm

Chunyang Wang,Shuangting Wang,Zengzhang Guo,Liping Wang,Chao Ma 보안공학연구지원센터 2014 International Journal of Signal Processing, Image Vol.7 No.5

The study on classification methods of hyperspectral image is a focal growing area in remote sensing applications because the wide spectral range, providing a very high spectral resolution, allows the detection and classification surfaces and chemical elements of the observed image. Semi-supervised learning method which takes a large number of unlabeled samples and minority labeled samples, improving classification and predicting the accuracy effectively have been a new research direction. In this paper we proposed a new semi-supervised classification method of hyperspectral image based on combining Renyi entropy and multinomial logistic regression algorithm. The multinomial logistic regression was performed to describe a direct relationship between the selected sample as and their category. A lot of unlabeled samples are constantly added to the sample data using Renyi entropy algorithm. The test analysis of image classification in test area showed the advantages of classification method based on combining Renyi entropy and multinomial logistic regression algorithm for hyperspectral remote sensing image.

A Method for k Nearest Neighbor Query of Line Segment in Obstructed Spaces

( Liping Zhang ),( Song Li ),( Yingying Guo ),( Xiaohong Hao ) 한국정보처리학회 2020 Journal of information processing systems Vol.16 No.2

In order to make up the deficiencies of the existing research results which cannot effectively deal with the nearest neighbor query based on the line segments in obstacle space, the k nearest neighbor query method of line segment in obstacle space is proposed and the STA_OLkNN algorithm under the circumstance of static obstacle data set is put forward. The query process is divided into two stages, including the filtering process and refining process. In the filtration process, according to the properties of the line segment Voronoi diagram, the corresponding pruning rules are proposed and the filtering algorithm is presented. In the refining process, according to the relationship of the position between the line segments, the corresponding distance expression method is put forward and the final result is obtained by comparing the distance. Theoretical research and experimental results show that the proposed algorithm can effectively deal with the problem of k nearest neighbor query of the line segment in the obstacle environment.

Coupled Orbit-attitude Saturated Control for Solar Sail in Earth-Moon 3-body System

Liping Wu,Yu Guo,Zhihao Zhu 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.11

This paper aims to investigate a coupled orbit-attitude control strategy for a kind of novel spacecraft, solar sail, to track the given orbit in Earth-Moon 3-Body dynamic environment in presence of the matched and mismatched disturbances, attitude control saturation, orbital modeling error and parametric uncertainties. A cascaded triple-loop control structure is proposed to deal with the strong couplings between the orbit and attitude systems. The inner loop focusing on the orbital effects on attitude dynamics, an adaptive saturation controller is proposed to achieve attitude angular tracking, where the uncertain inertia, unknown matched disturbance and saturated attitude control torque are compensated by combining the unknown knowledge. The middle loop is to handle the orbit effects on attitude kinematics facing the mismatched disturbance. In the outer loop, the effects of attitude systemon orbit dynamics are deal with, where an adaptive orbit controller is designed considering the uncertain optical parameter and orbital modeling error. The proposed control structure efficiently simplifies the coupled orbit-attitudecontrol design for solar sail. In contrast to traditional coupled controllers for solar sail, the proposed control laws do not require exact knowledge of parametric uncertainties, disturbances and orbit modeling errors. The combination of unknown information reduces the number of estimated parameters as well. The numerical simulation results demonstrate the effectiveness of the proposed control strategy.

Design and Analysis of the Directional Transport Device for Bulk Rod Materials in Sand Fixation Equipment

Zhuang Guo,Weiqiang Zheng,Liping Zhang,Fei Li 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.1

To address the problem that sand fixation equipment cannot use bulk rod material for conveying operations, a directional transport device for bulk rod materials is designed, which realizes the flipping conveying of rod material from horizontal to vertical direction. The rod material is directionally conveyed under the clamping of two adjacent forks of the chain conveyor belt. The directional turning process of the rod material is analysed using the discrete element method, and the operating principle and feasibility of the rod material’s directional transportation are explained. To optimize the working performance of the device, an orthogonal combination test is carried out through physical prototype, with the conveying thickness, filling rate and conveyance speed of the rod material as the experimental factors, and the rod material’s qualified rate as the test index. The test results show that the experimental factors mentioned above can be ranked from the filling rate, the conveyance speed and then to the conveyance thickness according to their degrees of influence on the delivery rate of rod materials. The optimal parameter combination is obtained, and the results are also verified by experiments. This study has solved the problem of directional transport device for bulk rod materials in sand fixation equipment, which has theoretical significance and application value in the design of sand fixation equipment material conveying system.

A Bi-objective Game-based Task Scheduling Method in Cloud Computing Environment

Wanwan Guo,Mengkai Zhao,Zhihua Cui,Liping Xie 한국인터넷정보학회 2022 KSII Transactions on Internet and Information Syst Vol.16 No.11

The task scheduling problem has received a lot of attention in recent years as a crucial area for research in the cloud environment. However, due to the difference in objectives considered by service providers and users, it has become a major challenge to resolve the conflicting interests of service providers and users while both can still take into account their respective objectives. Therefore, the task scheduling problem as a bi-objective game problem is formulated first, and then a task scheduling model based on the bi-objective game (TSBOG) is constructed. In this model, energy consumption and resource utilization, which are of concern to the service provider, and cost and task completion rate, which are of concern to the user, are calculated simultaneously. Furthermore, a many-objective evolutionary algorithm based on a partitioned collaborative selection strategy (MaOEA-PCS) has been developed to solve the TSBOG. The MaOEA-PCS can find a balance between population convergence and diversity by partitioning the objective space and selecting the best converging individuals from each region into the next generation. To balance the players' multiple objectives, a crossover and mutation operator based on dynamic games is proposed and applied to MaPEA-PCS as a player's strategy update mechanism. Finally, through a series of experiments, not only the effectiveness of the model compared to a normal many-objective model is demonstrated, but also the performance of MaOEA-PCS and the validity of DGame.

Synthesis of covalently crosslinked attapulgite/poly (acrylic acid-co-acrylamide) nanocomposite hydrogels and their evaluation as adsorbent for heavy metal ions

Peng Liu,Liping Jiang,Longxiang Zhu,Jinshan Guo,Aiqin Wang 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.23 No.-

Novel covalently crosslinked attapulgite/poly(acrylic acid-co-acrylamide) (ATP/P(AA-co-AM)) nanocomposite hydrogel was synthesized via a facile ‘‘one-pot’’ two-step approach, with the modified attapulgite (ATP–C55C) nanorods as the sole crosslinker. Orthogonal experiment was designed to investigate the effect of the synthetic condition on the resultant nanocomposite hydrogels. The ATP/ P(AA-co-AM)) nanocomposite hydrogels exhibited selective adsorption toward Pb2+ and Cu2+. The adsorbed ions could be easily desorbed, indicating their desired reusability. These excellent features, such as facile preparation, high mechanical stability, high adsorption capacity, and simple reactivation, make them potential adsorbent for the treatment of the heavy metal-contaminated water.

Bond Behaviors between Ribbed BFRP Bars and Ecological High Ductility Cementitious Composites

Lijuan Chai,Liping Guo,Bo Chen,Jiandong Wu 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.11

Direct pull-out method was conducted to explore the bond stress-slip response of ribbed basalt fiber reinforced polymer (BFRP) bars embedded in ecological high ductility cementitious composites (Eco-HDCCs). The effects of the embedment length and cover thickness on the bond properties between Eco-HDCCs and the bars were described. Results indicate that the failure characteristics of the specimens depend on the embedment length and cover thickness of the BFRP bars. As the embedment lengths of the bars increase, the ultimate bond stress decreases while the ultimate slip increases. Besides, both the ultimate bond stress and ultimate slip show an increasing trend if the specimen has a cover thickness of less than 45 mm, while the increasing trend is slower if the specimen has a cover thickness of more than 45 mm. In addition, the strain of the specimen surface depends on the cover thickness, and the strain increases when the cover thickness is in a range of 15 mm − 35 mm. Moreover, certain embedment lengths and cover thicknesses of the BFRP bars are recommended in the structural design of bridge deck link slabs. The bond stress-slip relationship models of the BFRP bars in Eco-HDCCs are proposed based on the test results.