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Automatic software fault localization based on artificial bee colony

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Journal of Systems Engineering and Electronics 2015年第6期26卷 1325-1332页

作者： Linzhi huang jun Ai School of Reliability and Systems Engineering Beihang University

Software debugging accounts for a vast majority of the financial and time costs in software developing and maintenance. Thus, approaches of software fault localization that can help automate the debugging process have become a hot topic in the field of software engineering. Given the great demand for software fault localization, an approach based on the artificial bee colony （ABC） algorithm is proposed to be integrated with other related techniques. In this process, the source program is initially instrumented after analyzing the dependence information. The test case sets are then compiled and run on the instrumented program, and execution results are input to the ABC algorithm. The algorithm can determine the largest fitness value and best food source by calculating the average fitness of the employed bees in the iteralive process. The program unit with the highest suspicion score corresponding to the best test case set is regarded as the final fault localization. Experiments are conducted with the TCAS program in the Siemens suite. Results demonstrate that the proposed fault localization method is effective and efficient. The ABC algorithm can efficiently avoid the local optimum, and ensure the validity of the fault location to a larger extent.

关键词： software debugging software fault localization arti-ficial bee colony (ABC) algorithm program instrumentation.

Viral infection of tobacco plants improves performance of Bemisia tabaci but more so for an invasive than for an indigenous biotype of the whitefly

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第1期11卷 30-40页

作者： Jian LIU Meng LI jun-min LI Chang-jun huang Xue-ping ZHOU Fang-cheng XU Shu-sheng LIU Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects Institute of Insect Sciences Zhejiang University Hangzhou 310029 China) Institute of Biotechnology Zhejiang University Hangzhou 310029 China Wenzhou Academy of Agricultural Sciences Wenzhou 325006 China

The ecological effects of plant-virus-vector interactions on invasion of alien plant viral vectors have been rarely investigated. We examined the transmission of Tomato yellow leaf cur/China virus （TYLCCNV） by the invasive Q biotype and the indigenous ZHJ2 biotype of the whitefly Bemisia tabaci, a plant viral vector, as well as the influence of TYLCCNV-infection of plants on the performance of the two whitefly biotypes. Both whitefly biotypes were able to acquire viruses from infected plants and retained them in their bodies, but were unable to transmit them to either tobacco or tomato plants. However, when the Q biotype fed on tobacco plants infected with TYLCCNV, its fecundity and longevity were increased by 7- and 1-fold, respectively, compared to those of the Q biotype fed on uninfected tobacco plants. When the ZHJ2 biotype fed on virus-infected plants, its fecundity and longevity were increased by only 2- and 0.5-fold, respectively. These data show that the Q biotype acquired higher beneficial effects from TYLCCNV-infection of tobacco plants than the ZHJ2 biotype. Thus, the Q biotype whitefly may have advantages in its invasion and displacement of the indigenous ZHJ2 biotype.

关键词： Bemisia tabaci Biotypes Begomovirus Vector-virus interaction Biological invasion

The effect of al particle size on thermal decomposition,mechanical strength and sensitivity of Al/ZrH_(2)/PTFE composite

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Defence Technology（防务技术） 2021年第3期17卷 829-835页

作者： jun Zhang Yu-chun Li jun-yi huang Jia-xiang Wu Qiang Liu Shuang-zhang Wu Zhen-ru Gao sheng Zhang Li Yang College of Field Engineering PLA Army Engineering UniversityNanjing210007China

To study the thermal decomposition of Al/Zr H_(2)/PTFE with different Al particle size as well as mechanical strength and impact sensitivity under medium and low strain rates,molding-vacuum sintering was adopted to prepare four groups of power materials and cylindrical specimens with different Al particle *** active decomposition temperature of Zr H_(2) was obtained by TG-DSC,and the quasi-static mechanics/reaction characteristics as well as the impact sensitivity of the specimen were studied respectively by quasi-static compression and drop-hammer *** results show that the yield strength of the material decreased with the increase of the Al particle size,while the compressive strength,failure strain and toughness increased first and then decreased,which reached the maximum values of 116.61 MPa,191%,and 119.9 MJ/m respectively when the Al particle size is 12-14 mm because of particle size *** specimens with the highest strength and toughness formed circumferential open cracks and reacted partly when *** with developmental cracks formed inside did not *** is considered that fracture of specimens first triggered initial reaction between Al and PTFE to release an amount of *** ZrH_(2) was activated and decomposed,and participated in subsequent reaction to generate Zr *** impact sensitivity of the specimens decreased with the increase of Al particle size.

关键词： Al/ZrH_(2)/PTFE Thermal decomposition Mechanical strength Reaction characteristics Impact sensitivity

Permeabilization of Escherichia coli with ampicillin for a whole cell biocatalyst with enhanced glutamate decarboxylase activity

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Chinese Journal of Chemical Engineering 2016年第7期24卷 909-913页

作者： Weirui Zhao sheng Hu jun huang Piyu Ke Shanjing Yao Yinlin Lei Lehe Mei Jinbo Wang School of Biotechnology and Chemical Engineering Ningbo Institute of Technology Zhejiang University Ningho 315100 China Department of Chemical and Biological Engineering Zhejiang University Hangzhou 310027 China School of Biological and Chemical Engineering Zhejiang University of Science and Technology Hangzhou 310023 China

The activity of whole-cell biocatalysts is strongly compromised by the cell envelope, which is a permeability harrier against the diffusion of substrates and products. Although common chemical or physical permeahilization methods used in cultured cells enhance cell permeability, these methods inevitably add several extra processing steps after cell cultivation, as well as impede large scale processing. To increase membrane permeability and cell- bound glutamate decarboxylase （GAD） activity of recombinant Escherichia coil （BL21 （DE3）-pET28a-gadB） cells without the need for an additional permeabilization step, we investigated the permeabilizing effects of adding cell wall synthesis inhibitors or suffactants to the culture media. Ampidllin was the most effective at improving cell-bound GAD activity of the BL21 （DE3）-pET28a-gadB, although it decreased the cell biomass yield. The best permeabilization effect was observed using an ampicillin concentration of 5 pg. ml-1. Using this concentration, the cell hiomass did decrease by 40.58%, but the cell-bound GAD activity of BL21 （DE3）-pET28a-gadB and total cell-bound GAD activity per milliliter of culture was enhanced by 6.24- and 3.64-fold, respectively. Treatment ofBL21 （DE3）-pET28a-gadB cells with 5 *** 1 ampicillin resulted in structural changes to the cell envelope, but did not substantially affect GAD expression. By entrapping the ampicillin-treated cells in an open pore gelation matrix, which is a polymer derived from polyvinyl alcohol （PVA）, alginate, and boric acid, the transfor- mation rate of γ-aminobutyric acid （GABA） at the 10th cycle produced by immobilized and permeabilized cells remained 46% of the first cycle. GAD activity of the immobilized, permeabilized cells remained over 90% after 30 days of storage at 4 ℃.

关键词： γ-Aminobutyric acidAmpicillinEscherichio. coilGlutamate decarboxylasePermeabilization

Pressure Effects on the Transport and Structural Properties of Metallic Glass-Forming Liquid

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Chinese Physics Letters 2020年第7期37卷 56-60页

作者： Qi-Long Cao Duo-Hui huang jun-sheng Yang Fan-Hou Wang Key Laboratory of Computational Physics Yibin UniversityYibin 644007China

Transport and structural properties of metallic glass-forming liquid Cu50Zr50 are investigated by molecular dynamics simulation,under high pressures from 1 bar to 70 *** following results have been obtained:(i)reversals of component diffusion coefficients(DCu and DZr)are observed at the reversion *** low pressures below the reversion pressure,DCu and DZr decreases from about 1.4 to *** high pressures above the reversion pressure,DCu and DZr decreases more rapidly from 1.0 to about 0.7.(ii)Component diffusion coefficients decay exponentially with pressure up to reversion pressure,then the strength of the exponential dependence changes,while the pressure-dependent behavior of viscosity can be well described by a single exponential relation over the full range of pressure.(iii)The Stokes–Einstein relation(SER)works well at low pressures and starts to be violated at the breakdown *** glass-forming liquid Cu50 Zr50 along the 2000 K isotherm,the breakdown pressure equals the reversion pressure of component diffusion coefficients and is about 35 GPa.(iv)The pressure dependences of the ratio between component diffusion coefficients can be used to predict the breakdown pressure of SER along *** validity of SER and the reversals of component diffusion coefficients are found to be related to the pressure dependence of the relative total fractions of predominant Voronoi polyhedrons around individual components.

关键词： pressure. diffusion isotherm

Pocket Modification of x-Amine Transaminase AtATA for Overcoming the Trade-Off Between Activity and Stability Toward 1-Acetonaphthone

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Engineering 2023年第11期30卷 203-214页

作者： Jiaren Cao Fangfang Fan Changjiang Lyu sheng Hu Weirui Zhao Jiaqi Mei Shuai Qiu Lehe Mei jun huang Key Laboratory of Chemical and Biological Processing Technology for Farm Products of Zhejiang Province Zhejiang Provincial Collaborative Innovation Center of Agricultural Biological Resources Biochemical ManufacturingSchool of Biological and Chemical EngineeringZhejiang University of Science and TechnologyHangzhou 310023China School of Biological and Chemical Engineering Ningbo Tech UniversityNingbo 315100China Hangzhou Huadong Medicine Group Co.Ltd. Hangzhou 310011China College of Chemical and Biological Engineering Zhejiang UniversityHangzhou 310027China Jinhua Advanced Research Institute Jinhua 321019China

Amine transaminases(ATAs)catalyze the asymmetric amination of prochiral ketones or aldehydes to their corresponding chiral ***,the trade-off between activity and stability in enzyme engineering represents a major obstacle to the practical application of *** this trade-off is important for developing robustly engineered enzymes and a universal approach for ***,we modified the binding pocket of co-ATA from Aspergillus terreus(AtATA)to identify the key amino acid residues controlling the activity and stability of AtATA toward *** discovered a structural switch comprising four key amino acid sites(R128,V149,L182,and L187),as well as the"best"mutant(AtATAD224K/V149A/L182 F/L187F;termed M4).Compared to the parent enzyme AtATAD224K(AtATAPa),M4 increased the catalytic efficiency(k_(cat)/K_(m)^(1-acetonaphthone),where kcatis the constant of catalytic activities and is 10.1 min^(-1),K_(m)^(1-acetonaphthoneis) Michaelis-Menten constant and is 1.7 mmol·L^(-1))and half-life(t1/2)by 59-fold to 5.9 L·min^(-1)·mmol-1and by 1.6-fold to 46.9 min,***,using M4 as the biocatalyst,we converted a 20 mmol·L^(-1)aliquot of 1-acetonaphthone in a 50 mL scaled-up system to the desired product,(R)-(+)-1(1-naphthyl)ethylamine((R)-NEA),with 78%yield and high enantiomeric purity(R>99.5%)within 10 h.M4 also displayed significantly enhanced activity toward various 1-acetonaphthone *** related structural properties derived by analyzing structure and sequence information of robust ATAs illustrated their enhanced activity and *** of intramolecular interactions and expansion of the angle between the substratebinding pocket and the pyridoxal 5’-phosphate(PLP)-binding pocket contributed to synchronous enhancement of ATA thermostability and ***,this pocket engineering strategy successfully transferred enhanced activity and thermostability to three other ATAs,which exhibited 8%-22%sequence simila

关键词： Trade-off Co-evolution Amine transaminase (R)-(+)-1(1-naphthyl)ethylamine

Effect of Three Gorges Dam on Poyang Lake water level at daily scale based on machine learning

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Journal of Geographical Sciences 2021年第11期31卷 1598-1614页

作者： huang sheng XIA jun ZENG Sidong WANG Yueling SHE Dunxian State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Hubei Key Laboratory of Water System Science for Sponge City Construction Wuhan UniversityWuhan 430072China Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources ResearchCASBeijing 100101China Chongqing Institute of Green and Intelligent Technology CASChongqing 400714China

Lake water level is an essential indicator of environmental changes caused by natural and human *** water level of Poyang Lake,the largest freshwater lake in China,has exhibited a dramatic variation for the past few years,especially after the completion of the Three Gorges Dam(TGD).However,there is a lack of more accurate assessment of the effect of the TGD on the Poyang Lake water level(PLWL)at finer temporal scales(e.g.,the daily scale).Here,we used three machine learning models,namely,an Artificial Neural Network(ANN),a Nonlinear Autoregressive model with exogenous input(NARX),and a Gated Recurrent Unit(GRU),to simulate the daily lake level during *** found that machine learning models with historical memory(i.e.,the GRU model)are more suitable for simulating the PLWL under the influence of the *** GRU-based results show that the lake level is significantly affected by the TGD regulation in the different operation stages and in different *** the TGD has had a slight but not very significant impact on the yearly decline of the PLWL,the blocking or releasing of water at the TGD at certain moments has caused large changes in the lake *** machine-learning-based study sheds light on the interactions between Poyang Lake and the Yangtze River regulated by the TGD.

关键词： water level Poyang Lake machine learning Three Gorges Dam Yangtze River

Microscopic sand production simulation and visual sanding pattern description in weakly consolidated sandstone reservoirs

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Petroleum Science 2022年第1期19卷 279-295页

作者： Chang-Yin Dong Bo Zhou Fan-sheng huang Lei Zhang Yi-Zhong Zhao Yang Song jun-Yu Deng Key Laboratory of Unconventional Oil&Gas Development Ministry of EducationQingdao266580ShandongPR China School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580ShandongPR China Research Institute of Petroleum Engineering Technology Shengli BranchSINOPECDongying257000ShandongPR China Research Ltd.of Engineering Technology CNPCTianjin345000PR China

To visually describe the sanding pattern,this study constructs a new particle-scale microstructure model of weakly consolidated formation,and develop the corresponding methodology to simulate the sanding process and predict sand cavity *** microstructure model is a particle-objective model,which focuses on the random sedimentation of every sand *** the microstructure,every particle has its own size,sphericity and inclination *** is used to simulate the actual structure of cemented granular materials,which considers the heterogeneity and randomness of reservoir properties,provides the initial status for subsequent sanding *** the particle detachment criteria,the microscopic simulation of sanding can be visually implemented to investigate the pattern and cavity shapes caused by sand *** results indicate that sanding always starts initially from the borehole border,and then extends along the weakly consolidated plane,showing obvious characteristic of *** typical microscopic sanding patterns,concerning pore liquefaction,pseudo wormhole and continuous collapse,are proposed to illustrate the sanding mechanism in weakly consolidated *** nonuniformity of sanding performance depends on the heterogeneous distribution of reservoir properties,such as rock strength and particle ***,the three sanding patterns are verified by visually experimental *** proposed integrated methodology is capable of predicting and describing the sanding cavity shape of an oil well after long-term sanding production,and providing the focus objective of future sand control measure.

关键词： Weakly consolidated reservoir Particle-scale microstructure model Microcosmic sanding process simulation Visual sanding cavity description Sanding prediction Sand control optimization

Effects of refractory period on dynamical range in excitable networks

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Chinese Physics B 2019年第12期28卷 378-382页

作者： Ya-Qin Dong Fan Wang sheng-jun Wang Zi-Gang huang School of Physics and Information Technology Shaanxi Normal UniversityXi'an 710119China School of Life Science and Technology Xi'an Jiaotong UniversityXi'an 710049China

Effects of refractory period on the dynamical range in excitable networks are studied by computer simulations and theoretical analysis. The first effect is that the maximum or peak of the dynamical range appears when the largest eigenvalue of adjacent matrix is larger than one. We present a modification of the theory of the critical point by considering the correlation between excited nodes and their neighbors, which is brought by the refractory period. Our analysis provides the interpretation for the shift of the peak of the dynamical range. The effect is negligible when the average degree of the network is large. The second effect is that the dynamical range increases as the length of refractory period increases, and it is independent of the average degree. We present the mechanism of the second effect. As the refractory period increases,the saturated response decreases. This makes the bottom boundary of the dynamical range smaller and the dynamical range extend.

关键词： criticality branching process random network dynamical range