Zhen Luo^1,2, Nong Zhang,^1,3

CMC-Computers, Materials & Continua, Vol.28, No.1, pp. 27-56, 2012, DOI:10.3970/cmc.2012.028.027

Abstract This paper attempts to present a new multi-criteria topological optimization methodology for the systematic design of compliant micro-mechanisms. Instead of employing only the strain energy (SE) or the functional specifications such as mechanical efficiency (ME), in this study an alternative formulation representing multiple design requirements is included in the optimization to describe the performance of compliant mechanisms. In most conventional designs, SE is used to only measure the design requirement from the point of view of structures, while ME is usually applied to describe the mechanical performance of mechanisms. However, the design of a compliant mechanism is required to comprehensively… More >

Suzhen Wang¹, Yanpiao Zhang¹, Lu Zhang¹, Ning Cao^{2, *}, Chaoyi Pang³

CMC-Computers, Materials & Continua, Vol.56, No.3, pp. 415-431, 2018, DOI: 10.3970/cmc.2018.03716

Abstract Spark is a fast unified analysis engine for big data and machine learning, in which the memory is a crucial resource. Resilient Distribution Datasets (RDDs) are parallel data structures that allow users explicitly persist intermediate results in memory or on disk, and each one can be divided into several partitions. During task execution, Spark automatically monitors cache usage on each node. And when there is a RDD that needs to be stored in the cache where the space is insufficient, the system would drop out old data partitions in a least recently used (LRU) fashion to release more space. However,… More >

Daofeng Li^1,3,*, Mingxing Luo², Bowen Zhao^1,3, Xiangdong Che⁴

CMC-Computers, Materials & Continua, Vol.56, No.3, pp. 447-465, 2018, DOI: 10.3970/cmc.2018.03692

Abstract The secure issues of APK are very important in Android applications. In order to solve potential secure problems and copyrights issues in redevelopment of APK files, in this paper we propose a new APK redevelopment mechanism (APK-SAN). By exploring sanitizable signature technology, APK-SAN allows the original developer to authorize specified modifier who can redevelop the designated source code of APK files. Our scheme does not require interactions between the developer and modifiers. It can reduce the communication overhead and computational overhead for developers. Especially, the signature of redeveloped APK files is valid and maintains the copyrights. The proposed APK-SAN signature… More >

Wen-Jay Lee^1,*, Yu-Chien Lo², Anchen Yang³, Kuanpeng Chen³, Nan-Yow Chen³

CMES-Computer Modeling in Engineering & Sciences, Vol.120, No.2, pp. 293-304, 2019, DOI:10.32604/cmes.2019.06620

Abstract Different thickness of amorphous/nanocrystalline multi-layered structure can be used to modulate the strength and ductility of the composite materials. In this work, molecular dynamics simulations were conducted to study the thickness effect of nanocrystalline layer on mechanical properties and deformation behavior of the Cu₆₄Zr₃₆/Cu multi-layer structure. The stress-strain relationship, local stress, local strain, and deformation mechanism are investigated. The results reveal that the change of thickness of the crystalline layer significantly affects the mechanical properties and deformation behavior. As the strain at the elastic region, the amorphous Cu₆₄Zr₃₆ layer dominates the mechanical behavior, leading the fact that Young’s modulus, first… More >

Gongyu Hou¹, Zhedong Xu^1,*, Xin Liu¹, Cong Jin¹

CMES-Computer Modeling in Engineering & Sciences, Vol.118, No.2, pp. 317-337, 2019, DOI:10.31614/cmes.2019.04693

Abstract This article proposes an exponential adjustment inertia weight immune particle swarm optimization (EAIW-IPSO) to enhance the accuracy and reliability regarding the selection of shield tunneling parameter values. According to the iteration changes and the range of inertia weight in particle swarm optimization algorithm (PSO), the inertia weight is adjusted by the form of exponential function. Meanwhile, the self-regulation mechanism of the immune system is combined with the PSO. 12 benchmark functions and the realistic cases of shield tunneling parameter value selection are utilized to demonstrate the feasibility and accuracy of the proposed EAIW-IPSO algorithm. Comparison with other improved PSO indicates… More >

Yang Yang^{1, *}

CMES-Computer Modeling in Engineering & Sciences, Vol.116, No.3, pp. 365-389, 2018, DOI: 10.31614/cmes.2018.03847

Abstract The selection of machining parameters directly affects the production time, quality, cost, and other process performance measures for multi-pass milling. Optimization of machining parameters is of great significance. However, it is a nonlinear constrained optimization problem, which is very difficult to obtain satisfactory solutions by traditional optimization methods. A new optimization technique combined chaotic operator and imperialist competitive algorithm (ICA) is proposed to solve this problem. The ICA simulates the competition between the empires. It is a population-based meta-heuristic algorithm for unconstrained optimization problems. Imperialist development operator based on chaotic sequence is introduced to improve the local search of ICA,… More >

Junmeng Li¹, Yanli Huang¹, Wenyue Qi¹, Guoqiang Kong¹, Tianqi Song¹

CMES-Computer Modeling in Engineering & Sciences, Vol.115, No.1, pp. 85-103, 2018, DOI:10.3970/cmes.2018.115.085

Abstract In fully mechanized solid backfilling mining (FMSBM), the loose gangues backfill body (LGBB) that filled into the goaf becomes the main body of bearing the overburden load. The deformation resistance of LGBB is critical for controlling overburden movement and surface subsidence. During the process of load bearing, LGBB will experience grain crushing, which has a significant effect on its deformation resistance. Gangues block will be accompanied with obvious acoustic emissions (AE) features in process of slipping, flipping and damaging. Under confined compression test, monitoring the AE parameters of LGBB can reveal the impact mechanism of grain crushing on LGBB deformation.… More >

Zhengzheng Cao¹, Feng Du^2,3,4, Zhenhua Li², Qinting Wang¹, Ping Xu¹, Haixiao Lin¹

CMES-Computer Modeling in Engineering & Sciences, Vol.113, No.3, pp. 275-293, 2017, DOI:10.3970/cmes.2017.113.287

Abstract The stability of ore pillar in mine is essential for the safe and efficient mining. Based on the energy evolvement rule in ore pillar and roadway roof system, the roadway roof and ore pillar are treated as energy release body and energy dissipation body, respectively. Therefore, the double-block mechanical model is established with energy dissipation body and energy release body, and the energy mechanism of ore pillar instability is obtained, based on the fold catastrophe mathematical theory. The research result indicates that the dynamic instability of ore pillar is a physical instability problem caused by the strain softening property of… More >

Wang Yang^1,2, Juanjuan Li¹, Jian Yang^1,3, Lin Wei⁴

CMES-Computer Modeling in Engineering & Sciences, Vol.104, No.6, pp. 471-491, 2015, DOI:10.3970/cmes.2015.104.471

Abstract Harvesting is the most difficult and costly operation in cassava production. Currently, most cassava harvest still depends on manual tools. Effective mechanized harvesters are necessary to improve harvesting quality and reduce production cost. Therefore, it is very important to figure out key information for designing an effective tuber lifting system used in bionic “dig-pull” harvesters. A numerical simulation model of human-stem-tuber-soil system was developed to carry out numerical simulation of manually pulling tuber. Coupling algorithm of Lagrange and smoothed particle hydrodynamics (SPH) was used in the model. Lifting mechanism of experienced farmer was studied at a micro level. Influence of… More >

S.M. Pradhan¹, K.S.Katti¹, D.R. Katti¹

CMES-Computer Modeling in Engineering & Sciences, Vol.98, No.2, pp. 181-201, 2014, DOI:10.3970/cmes.2014.098.181

Abstract Multiscale modeling of collagen fibril is carried out by incorporating the material properties of collagen obtained from steered molecular dynamics into the finite element model of collagen fibril with inclusion of crosslinks. The results indicate that the nonbonded interactions between collagen and mineral contribute to the significant enhancement of the elastic modulus of collagen fibril at all the crosslink densities in both the low strain and high strain regimes. The crosslinks are found to play an important role in the mechanical response of collagen fibril, the enhancement in elastic modulus ranging from 5-11% for various crosslink densities compared to the… More >