In this paper, we investigate the characteristics of membrane fouling caused by water temperature in the Membrane bioreactor(MBR) process and try to derive the membrane fouling control by chemical enhanced backwashing(CEB). The extracellular polymeric substances(EPS) concentration was analyzed according to the water temperature in the MBR, and the membrane fouling characteristics were investigated according to the conditions, with sludge & without sludge, through a lab-scale reactor. As shown in the existing literature the fouling resistance rate was increased within sludge with the water temperature was lowered. However, in the lab-scale test using the synthetic wastewater, the fouling resistance increased with the water temperature. This is because that the protein of the EPS was more easily adsorbed on the membrane surface due to the increase of entropy due to the structural rearrangement of the protein inside the protein as the water temperature increases. In order to control membrane fouling, we tried to derive the cleaning characteristics of CEB by using sodium hypochlorite(NaOCl). We selected the condition with the chemicals and the retention time, and the higher the water temperature and the chemical concentration are the higher the efficiencies. It is considered that the increasing temperature accelerated the chemical reaction such as protein peptide binding and hydrolysis, so that the attached proteinaceous structure was dissolved and the frequency of the reaction collision with the protein with the chemical agent becomes higher. These results suggest that the MBRs operation focus on the fouling control of cake layer on membrane surface in low temperatures. On the other hand, the higher the water temperature is the more the operation strategies of fouling control by soluble EPS adsorption are needed.

Membrane bioreactors (MBRs) employ a process of biological treatment that is based on a membrane that has the advantages of producing high-quality treated water and possessing a compact footprint. However, despite these advantages, the occurrence of “fouling” during the operation of these reactors causes the difficulty of maintenance.Hence, in this study, three physical cleaning methods, namely, backwashing, air scrubbing, and mechanical cleaning ball was performed to identify optimum operating conditions through laboratory scale experiments, and apply them in a pilot plant. Further, the existing MBR process was compared with these methods, and the field applicability of a combination of these physical cleaning methods was investigated.Consequently, MCB, direct control of cake fouling on the membrane surface was found to be the most effective. Moreover, as a result of operating with combination of the physical cleaning process in a pilot plant, the TMP increasing rate was found to be – 0.00007 MPa/day, which was 185% higher than that obtained using the existing MBR process. Therefore, assuming fouling only by cake filtration, about one year of operation without chemical cleaning is considered to be feasible through the optimization of the physical cleaning methods.

This paper presents a vision-based relative pose estimation algorithm and its validation through both numerical and hardware experiments. The algorithm and the hardware system were simultaneously designed considering actual experimental conditions. Two estimation techniques were utilized to estimate relative pose; one was a nonlinear least square method for initial estimation, and the other was an extended Kalman Filter for subsequent on-line estimation. A measurement model of the vision sensor and equations of motion including nonlinear perturbations were utilized in the estimation process. Numerical simulations were performed and analyzed for both the autonomous docking and formation flying scenarios. A configuration of LED-based beacons was designed to avoid measurement singularity, and its structural information was implemented in the estimation algorithm. The proposed algorithm was verified again in the experimental environment by using the Autonomous Spacecraft Test Environment for Rendezvous In proXimity (ASTERIX) facility. Additionally, a laser distance meter was added to the estimation algorithm to improve the relative position estimation accuracy. Throughout this study, the performance required for autonomous docking could be presented by confirming the change in estimation accuracy with respect to the level of measurement error. In addition, hardware experiments confirmed the effectiveness of the suggested algorithm and its applicability to actual tasks in the real world.

For purposes of studying intron structures and predicting consensus splice motifs, a total of 102 legume species were used to isolate introns across the family. Of 196 gene-targeted PCR primer pairs, we successfully amplified 118 intron-containing genes (60.2%) and obtained a total of 1,870 introns with an average size of 143 nucleotides. Species-based compilation of 5’- and 3’-splicing motifs showed lineage-specific conservation in each splicing motif. Compilation of the entire intron set permitted prediction of the consensus sequences of splicing signal motifs in legumes, AYGWGTABABGH and TVNC/TAGGHTV for the 5’- and 3’-splicing motifs, respectively. Interestingly, these consensus motifs are very similar to the corresponding splicing signals of two model systems, Arabidopsis and rice. This result is suggestive of conservation of pre-mRNA splicing mechanisms in higher plants. Multiple alignments of CALTL introns demonstrated that the region from the branch point to 3’ splice site was relatively more conserved than the region from5’ splice site to the branch point. Phylogenetic analysis demonstrated that each of three splicing motifs, 5’-splice sites, 3’-splice sits, and branch site, was relevant to evolutionary divergence of species and phylogenetically informative, suggesting that splice signal sequences would be useful as a potential tool for the molecular phylogenetic analysis.

A core genetic map of the legume Medicago truncatula has been established by analyzing the segregation of 288 sequence-characterized genetic markers in an F2 population composed of 93 individuals. These molecular markers correspond to 141 ESTs, 80 BAC end sequence-tags, and 67 resistance gene analogs, covering 513 cM. In the case of EST-based markers we used an intron-targeted marker strategy, with primers designed to anneal in conserved exon regions and amplify across intron regions. Polymorphisms were significantly more frequent in intron vs exon regions, thus providing an efficient mechanism to map transcribed genes. Genetic and cytogenetic analysis produced eight well-resolved linkage groups, which have been previously correlated with eight chromosomes by means of FISH with mapped BAC clones. We anticipated that mapping of conserved coding regions would have utility for comparative mapping among legumes; thus 60 of the EST-based primer pairs were designed to amplify orthologous sequences across a range of legume species. As an initial test of this strategy, we used primers designed against M. truncatula exon sequences to rapidly map genes in Medicago sativa. The resulting comparative map, which includes 68 bridging markers, indicates that the two Medicago genomes are highly similar, and establishes the basis for a “Medicago” composite map.

Cross-species translation of genomic information may play a pivotal role in applying biological knowledge gained from one species to other genomes. Abiotic stress-responsive genes in Arabidopsis have been translated to a legume model system, Medicago truncatula. A total of 1,370 Arabidopsis genes were identified by searching TAIR database, expression profiling data and literatures. For purposes of cross-genome identification of orthologous genes, tBlastX or BlastP were employed between these two model systems. Candidate genes potentially associated with abiotic stress responses were classified into 18 functional criteria and corresponding genomic locations were analyzed by Circos program. To do this, user-friendly bioinformatic analysis platform was established. In order to discover abiotic stress-associated genes, gene network and/or interactome analyses were conducted using a combination of AraNet web-based platform and CytoScape program. As a result, we could identify 240 key genes that appeared to play an important role within central gene networks. We anticipate that these genes may impact molecular breeding programs by developing them into genetic markers and discovering trait-associated nucleotide variations.