Adaptive Application Component Mapping for Parallel Computation Offloading in Variable Environments

( Wenhao Fan ),( Yuan`an Liu ),( Bihua Tang ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.11

Distinguished with traditional strategies which offload an application`s computation to a single server, parallel computation offloading can promote the performance by simultaneously delivering the computation to multiple computing resources around the mobile terminal. However, due to the variability of communication and computation environments, static application component multi-partitioning algorithms are difficult to maintain the optimality of their solutions in time-varying scenarios, whereas, over-frequent algorithm executions triggered by changes of environments may bring excessive algorithm costs. To this end, an adaptive application component mapping algorithm for parallel computation offloading in variable environments is proposed in this paper, which aims at minimizing computation costs and inter-resource communication costs. It can provide the terminal a suitable solution for the current environment with a low incremental algorithm cost. We represent the application component multi-partitioning problem as a graph mapping model, then convert it into a pathfinding problem. A genetic algorithm enhanced by an elite-based immigrants mechanism is designed to obtain the solution adaptively, which can dynamically adjust the precision of the solution and boost the searching speed as transmission and processing speeds change. Simulation results demonstrate that our algorithm can promote the performance efficiently, and it is superior to the traditional approaches under variable environments to a large extent.

An API Calls Monitoring-based Method for Effectively Detecting Malicious Repackaged Applications

Wenhao Fan,Yuan’an Liu,Bihua Tang 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.8

The number of mobile applications on Android platform has largely increased in recent years. The security problems, as one of the outcomes induced by the popularity of Android, become more and more critical. Malicious repackaged applications (MRAs) perform malicious behaviors through malware developers embedding malicious codes into the benign origin applications (BOAs), which threat the security of users’ finance and privacy. In this paper, a method based on API calls monitoring is proposed to effectively detect MRAs. We discuss the characteristics of behaviors and analyze the differences in API calls between MRAs and their BOAs. A MRA detection model is established, which builds up the super-sphere for each BOA via a SVDD algorithm. The model can detect the abnormal behaviors of MRAs which deviate the normal behaviors of corresponding BOAs. Experiments are carried out on imitated and real MRAs, where the results demonstrate the effectiveness of our method for detecting the singly and multiply contaminated BOAs.

Energy Efficient Traffic Allocation for Resource-constrained Multi-homed WSN Gateway

Wenhao Fan,Bihua Tang,Yuan’an Liu 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.10

WSN (Wireless Sensor Network) gateway acts as a bridge between WSN and external networks. Currently, rapid growing demands from various IoTs (Internet of Things) applications are posing critical challenges to the data transmission capability of such gateway. As a promising solution, multi-homed WSN gateway, which is equipped with multiple network interfaces, can obtain enhanced parallel data transmission by jointly utilizing multiple RATs (Radio Access Technologies). However, the multi-homed gateway is a resource-constrained device, so it’s crucial to guarantee the efficiency for both data throughput and resource consumption. Delay and buffer size, simulation results validate that the proposed algorithm can allocate To this end, an energy efficient traffic allocation algorithm for resource-constrained multi-homed WSN gateway is proposed in this paper, which aims at minimizing the gateway's power consumption while guaranteeing the transmission the traffic optimally for the gateway with different constraints and configurations, and it can significantly promote the gateway's energy efficiency in comparison to the traditional method.

Application Multi-partitioning for Offloading Computation to Multiple Computing Resources around Mobile Terminals

Wenhao Fan,Bihua Tang,Yuan’an Liu 보안공학연구지원센터 2016 International Journal of Grid and Distributed Comp Vol.9 No.6

Different with traditional approaches that offload computation to a single remote server, the performance of an application can be further enhanced by simultaneously distributing its computing tasks to multiple computing resources around the mobile terminal. How to effectively multiply partition application components is critical for parallel computation offloading. In this paper, an application multi-partitioning scheme is proposed, which optimally offloads application's components to surrounding resources. A graph mapping model is converted and set up to represent components and resources as undirected graphs, and the A* algorithm is employed to efficiently search the optimal mapping from component graph to resource graph, which minimizes computing costs and inter-resource communication costs. Simulation results demonstrate that the performance can be efficiently promoted by our algorithm, which outperforms the traditional approaches to a large degree.

Improved Informed-RRT* Based Path Planning and Trajectory Optimization for Mobile Robots

Laohu Yuan,Jiance Zhao,Wenhao Li,Jian Hou 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.3

In order to solve the problems of the Informed-RRT* algorithm in path planning, such as blindness, uneven sampling, and unsmooth paths, an improved Informed-RRT* algorithm based on adaptive growth strategy and elliptical region variable weight sampling strategy with trajectory optimization is proposed in this paper. At first, an adaptive growth strategy is developed to address the blindness issue by considering the effect of the target point and any obstacles when selecting new nodes. Second, to address the issue of unequal sampling within the ellipse, an elliptical region variable weight sampling strategy is presented. This strategy increases the number of nodes in the vicinity of the target point. Finally, the minimum snap method is used to determine the best trajectory for the non-smooth path. The dynamic corridor constraint is used to reduce the difference between the trajectory and the path as small as possible while avoiding collisions with obstacles. The simulation experiments show that the improved algorithm cuts by 27.83% the time it takes to find the initial path, and by 16.91% the time it takes to find the best path. The optimized and smoothed path can be turned into acceleration at the right time to make motion control easier.

Fractal kinetic characteristics of uranium leaching from low permeability uranium-bearing sandstone

Sheng Zeng,Yuan Shen,Bing Sun,Kaixuan Tan,Shuwen Zhang,Wenhao Ye 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.4

The pore structure of uranium-bearing sandstone is one of the critical factors that affect the uraniumleaching performance. In this article, uranium-bearing sandstone from the Yili Basin, Xinjiang, China, wastaken as the research object. The fractal characteristics of the pore structure of the uranium-bearingsandstone were studied using mercury intrusion experiments and fractal theory, and the fractaldimension of the uranium-bearing sandstone was calculated. In addition, the effect of the fractal characteristics of the pore structure of the uranium-bearing sandstone on the uranium leaching kinetics wasstudied. Then, the kinetics was analyzed using a shrinking nuclear model, and it was determined that therate of uranium leaching is mainly controlled by the diffusion reaction, and the dissolution rate constant(K) is linearly related to the pore specific surface fractal dimension (DS) and the pore volume fractaldimension (DV). Eventually, fractal kinetic models for predicting the in-situ leaching kinetics wereestablished using the unreacted shrinking core model, and the linear relationship between the fractaldimension of the sample's pore structure and the dissolution rate during the leaching was fitted.

Temperature distribution prediction in longitudinal ballastless slab track with various neural network methods

Rui Zhou,Hanlin Liu,Wenhao Yuan,Yanliang Du,Jingmang Xu,Rong Chen 국제구조공학회 2023 Smart Structures and Systems, An International Jou Vol.32 No.2

The temperature prediction approaches of three important locations in an operational longitudinal slab track-bridge structure by using three typical neural network methods based on the field measuring platform of four meteorological factors and internal temperature. The measurement experiment of four meteorological factors (e.g., ambient temperature, solar radiation, wind speed, and humidity) temperature in the three locations of the longitudinal slab and base plate of three important locations (e.g., mid-span, beam end, and Wide-Narrow Joint) were conducted, and then their characteristics were analyzed, respectively. Furthermore, temperature prediction effects of three locations under five various meteorological conditions are tested by using three neural network methods, respectively, including the Artificial Neural Network (ANN), the Long Short-Term Memory (LSTM), and the Convolutional Neural Network (CNN). More importantly, the predicted effects of solar radiation in four meteorological factors could be identified with three indicators (e.g., Root Means Square Error, Mean Absolute Error, Correlation Coefficient of R2). In addition, the LSTM method shows the best performance, while the CNN method has the best prediction effect by only considering a single meteorological factor.

Seepage characteristics of the leaching solution during in situ leaching of uranium

Zeng Sheng,Song Jiayin,Sun Bing,Wang Fulin,Ye Wenhao,Shen Yuan,Li Hao 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.2

Investigating the seepage characteristics of the leaching solution in the ore-bearing layer during the in situ leaching process can be useful for designing the process parameters for the uranium mining well.We prepared leaching solutions of four different viscosities and conducted experiments using a selfdeveloped multifunctional uranium ore seepage test device. The effects of different viscosities of leaching solutions on the seepage characteristics of uranium-bearing sandstones were examined using seepage mechanics, physicochemical seepage theory, and dissolution erosion mechanism. Results indicated that while the seepage characteristics of various viscosities of leaching solutions were the same in rock samples with similar internal pore architectures, there were regular differences between the saturated and the unsaturated stages. In addition, the time required for the specimen to reach saturation varied with the viscosity of the leaching solution. The higher the viscosity of the solution, the slower the seepage flow from the unsaturated stage to the saturated stage. Furthermore, during the saturation stage, the seepage pressure of a leaching solution with a high viscosity was greater than that of a leaching solution with a low viscosity. However, the permeability coefficient of the high viscosity leaching solution was less than that of a low viscosity leaching solution.