Activity Sequence Modes for Web Services and Verifications

Behavior requirement expression and its satisfiability verification for composite Web services is one of the ongoing issues in service computing. In this paper, the concept of behavior specifications based on activity sequence is proposed to express one kind of behavioral requirements for composite Web services. Its basic element is activity sequence. The method to express such behavioral requirements by behavioral modes is presented. Five behavioral modes used in this method are adopted. Through map- ping modes to Labeled Transition Systems （LTSs）, these modes are encoded with exact operation semantics. Then, the sufficient and necessary conditions as well as the checking algorithm for satisfiability of behavioral modes are given. Finally, an example analysis is presented. The result indicates that the behavioral requirements based on activity sequence are more suitable for the case of composite Web service than those based on activity or scenario. The behavioral modes expressions are concise and the satisfiability checking is effective by the given algorithm.

Learning Activity Sequencing in Personalized Education System

Personalized education provides an open learning environment which enriches the advanced technologies to establish a paradigm shift, active and dynamic teaching and learning patterns. E-learning has a various established approaches to the creation and sequencing of content-based, single learner, and self-paced learning objects. However, there is little understanding of how to create sequences of learning activities which involve groups of learners interacting within a structured set of collaborative environments. In this paper, we present an approach for learning activity sequencing based on ontology and activity graph in personalized education system. Modeling and management of learning activity and learner are depicted, and an algorithm is proposed to realize learning activity sequencing and learner ontology dynamically updating.

Seismic Sequence Characteristics and Precursory Anomalies of the M_S6.3 and M_S6.4 Da Qaidam Earthquakes in 2008～2009

In this paper,the seismogenic structures of the Da Qaidam strong earthquakes are preliminarily discussed by using the regional seismotectonic data and focal mechanism solutions. Analysis is done on the temporal and spatial distribution characteristics of the two strong earthquake sequences in Da Qaidam in combination with the sequence distribution characteristics of the M6. 6 earthquake of 2003 and the five strong earthquakes of about M5. 0 in 2004 in Delingha. At the same time,the regional characteristics of the historical seismic activity are also investigated. Preliminary analysis is done on the influence of the two M8. 0 earthquakes in the past 10 years on this region. Precursory anomalies and their characteristics are discussed in combination with the analysis of the precursor observation data of Qinghai Province.

Applying the Hidden Markov Model to Analyze Urban Mobility Patterns: An Interdisciplinary Approach

With the emergence of the Internet of Things(IoT), there has been a proliferation of urban studies using big data. Yet, another type of urban research innovations that involve interdisciplinary thinking and methods remains underdeveloped. This paper represents an attempt to adopt a Hidden Markov Model(HMM) toolbox developed in Computer Science for the analysis of eye movement patterns in Psychology to answer urban mobility questions in Geography. The main idea is that both people’s eye movements and travel behavior follow the stop-travel-stop pattern, which can be summarized using HMM. Methodological challenges were addressed by adjusting the HMM to analyze territory-wide travel survey data in Hong Kong, China. By using the adjusted toolbox to identify the activitytravel patterns of working adults in Hong Kong, two distinctive groups of balanced(38.4%) and work-oriented(61.6%) lifestyles were identified. With some notable exceptions, working adults living in the urban core were having a more work-oriented lifestyle. Those with a balanced lifestyle were having a relatively compact zone of non-work activities around their homes but a relatively long commuting distance. Furthermore, working females tend to spend more time at home than their counterparts, regardless of their marital status and lifestyle. Overall, this interdisciplinary research demonstrates an attempt to integrate spatial, temporal, and sequential information for understanding people’s behavior in urban mobility research.

A novel digital control strategy of three-phase shunt active power filter under non-ideal mains voltages

A novel control strategy for three-phase shunt active power filter (SAPF) was proposed to improve its performance under non-ideal mains voltages. The approach was inspired by our finding that the classic instantaneous reactive power theory based algorithm was unsatisfactory in terms of isolating positive sequence fundamental active components exactly under non-ideal mains voltages. So, a modified ip-iq reference current calculation method was presented. With usage of the new method, not only the positive sequence but also the fundamental active current components can be accurately isolated from load current. A deadbeat closed-loop control model is built in order to eliminate both delay error and tracking error between reference voltages and compensation voltages under unbalanced and distorted mains voltages. Computer simulation results show that the proposed strategy is effective with better tracking ability and lower total harmonic distortion (THD). The strategy is also applied to a 10 kV substation with a local electrolysis manganese plant injecting a large amount of harmonics into the power system, and is proved to be more practical and efficient.

Expression and Activities Experiment of DNA Transduction Motif Based on GAL4 in Pichia Pastoris

The genes encoding DNA-binding domain（BD） designed based on the yeast transcriptional activator GAL4 and protein transduction domain of HIV-1 Tat protein were fused via soft linker peptide sequence, and cloned into yeast expression vector pPIC9k. The resulted plasmid pTG was linearized and transfected into Pichia pastoris strains GS 115 by electroporation. High copies of transformants were obtained with Muts and HIS＋ phenotype identi- fication, PCR amplification and screening of G418. After flask culture and expression induced by methanol, the target protein named TG was well expressed and analyzed by SDS-PAGE and Western blot. Under optimized conditions, the yield of soluble recombinant protein was approximately 39.7 mg/L. DNA binding activity and cell transduction property of TG were analyzed by gel eleetrophoresis and fluorescent microscopy. The results show that the recombinant protein could bind strongly to the plasmid containing upstream activating sequence（UAS）. The cell experiments revealed that TG could deliver the binding plasmid into HEK-293 cells effectively. In summary, the work presented here suggests that TG is specific toward UAS containing plasmid and has the potential for use as nonviral DNA delivery agent.

Combined process of sequencing batch reactor activated sludge process and constructed wetland for domestic wastewater treatment

By combining sequencing batch reactor (SBR) activated sludge process and constructed wetland (CW), this study is to achieve the domestic wastewater treatment. Our purpose was to determine the optimum operating parameters of the combined process. The process involved advantages and shortages of SBR and CW. Under normal temperature, the 3rd cycle (SBR’s operation cycle is 8 h: inflow for 1 h, limited aeration for 3 h, sediment for 1 h, outflow for 1 h, and idling for 2 h; CW’s hydraulic retention time (HRT) is 24.8 h and hydraulic loading is 24.5 m3/m2 d) was the best cyclic mode. The effluents can meet the standard GB/T18921-2002: "The reuse of urban recycling water: water quality standard for scenic environment use". In the 3rd cycle, the efficiency of CW was the maximum, and energy consumption of SBR was the minimum. Under the condition of low dissolved oxygen, the removing efficiency of chemical oxygen demand (COD) and ammonia was not affected obviously. Simultaneously, nitrification and denitrification phenomena occured and phosphorus was absorbed obviously.

Production of Poly-b-hydroxybutyrate by Activated Sludge in Sequencing Batch Reactor under Aerobic Conditions

In order to improve poly-β-hydroxybutyrate（PHB） production in activated sludge, the anaerobic/aerobic alternative operating sequencing batch reactor（SBR） process was applied in this paper to accumulate PHB. Effects of nutritional conditions and carbon concentration on PHB accumulation were studied. Results indicated that PHB accumulation reached the highest level and accounted for 11.2 % under anaerobic condition for phosphate limitation and 20.84 % under aerobic condition for nitrogen and phosphate limitation of mixed liquor suspended solid（MLSS）, respectively. In addition, 4 g/L was proved to be the optimum carbon concentration in both anaerobic and aerobic experiments, and the PHB accumulation reached 17.1 %（anaerobic, phosphorus limitation） and 60.4 %（aerobic, nitrogen and phosphorus limitation） of MLSS, respectively. PHB could be successfully extracted with sodium hypochlorite and chloroform method from the activated sludge. In addition, the infrared spectrum showed that the PHB sample extracted was of high purity.

Characterizing and engineering promoters for metabolic engineering of Ogataea polymorpha

Bio-manufacturing via microbial cell factory requires large promoter library for fine-tuned metabolic engi-neering.Ogataea polymorpha,one of the methylotrophic yeasts,possesses advantages in broad substrate spec-trum,thermal-tolerance,and capacity to achieve high-density fermentation.However,a limited number of available promoters hinders the engineering of O.polymorpha for bio-productions.Here,we systematically characterized native promoters in O.polymorpha by both GFP fluorescence and fatty alcohol biosynthesis.Ten constitutive promoters(P_(PDH),P_(PYK),P_(FBA),P_(PGM),P_(GLK),P_(TRI),P(GPI),P_(ADH1),P_(TEF1) and P_(GCW14))were obtained with the activity range of 13%–130% of the common promoter P_(GAP)(the promoter of glyceraldehyde-3-phosphate de-hydrogenase),among which P_(PDH) and P_(GCW14) were further verified by biosynthesis of fatty alcohol.Furthermore,the inducible promoters,including ethanol-induced P_(ICL1),rhamnose-induced P_(LRA3) and P_( LRA4),and a bidirectional promoter(P_(Mal)-P_(Per))that is strongly induced by sucrose,further expanded the promoter toolbox in O.polymorpha.Finally,a series of hybrid promoters were constructed via engineering upstream activation sequence(UAS),which increased the activity of native promoter P LRA3 by 4.7–10.4 times without obvious leakage expression.Therefore,this study provided a group of constitutive,inducible,and hybrid promoters for metabolic engineering of O.polymorpha,and also a feasible strategy for rationally regulating the promoter strength.

Using chimeric piggyBac transposase to achieve directed interplasmid transposition in silkworm Bombyx mori and fruit fly Drosophila cells

The piggyBac transposon has been long used to integrate foreign DNA into insect genomes.However,undesirable transgene expression can result from random insertions into the genome.In this study,the efficiency of chimeric Gal4-piggyBac transposase in directing integration onto a DNA target plasmid was evaluated in cultured silkworm Bombyx mori Bm-12 and fruit fly Drosophila Schneider 2(S2) cells.The Gal4-piggyBac transposase has a Gal4 DNA-binding domain(DBD),and the target plasmid has upstream activating sequences(UAS) to which the Gal4 DBD can bind with high affinity.The results indicate that,in the Bm-12 and S2 cells,transpositional activity of Gal4-piggyBac transposase was increased by 4.0 and 7.5 times,respectively,compared to controls,where Gal4-UAS interaction was absent.Moreover,the Gal4-piggyBac transposase had the ability of directing piggyBac element integration to certain sites of the target plasmid,although the target-directing specificity was not as high as expected.The chimeric piggyBac transposase has the potential for use in site-directed transgenesis and gene function research in B.mori.