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Corynebacterium glutamicum is known as a host species for amino acid production. This microorganism was recently noticed as a host that produces secreted proteins. In this study, we performed ~(13)C metabolic flux analysis (~(13)C...
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Corynebacterium glutamicum is known as a host species for amino acid production. This microorganism was recently noticed as a host that produces secreted proteins. In this study, we performed ~(13)C metabolic flux analysis (~(13)C-MFA) on a recombinant C. glutamicum strain that secretes a heterologous transglutaminase (TGase) to improve TGase secretion. For the ~(13)C-MFA of a TGase-secreting C. glutamicum strain in batch cultivation, a ~(13)C-labeling experiment and measurement of mass isotopomer distributions of proteinogenic amino acids were performed, and metabolic fluxes were determined considering the changes in fractional ~(13)C-labeling of proteinogenic amino acids with respect to culture time. The TGase yield increased at the stationary phase but decreased toward its end. The results of ~(13)C-MFA revealed that the flux from glycolysis to the TCA cycle gradually increased during TGase secretion. We speculate that the NADH/NAD~+ ratio in the cells increases and that as a result, the specific glucose uptake rate decreases in the stationary phase because of the increased flux of the TCA cycle. Since it is expected that a decrease in the NADH/NAD~+ ratio would improve the TGase yield, we tried to enhance lactate production in a TGase-secreting C. glutamicum strain to decrease cellular NADH levels by increasing the pH level in the culture. The TGase yield increased in 1.4-fold by increasing the pH from 6.7 to 7.2, indicating that the TGase yield was successfully improved on the basis of the ~C-MFA.
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A lightpath design and management system with parallel processing capabilities and a flexible upgradability has been designed and implemented for IP-over-CWDM networks with ROADMs. The system can process applications composed of s...
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A lightpath design and management system with parallel processing capabilities and a flexible upgradability has been designed and implemented for IP-over-CWDM networks with ROADMs. The system can process applications composed of some sub applications in parallel in multi machines for high-speed performance. In addition, the system was designed to have a flexible upgradability, i.e. no changes of the system programs are required when adding new functions. The system functions are to design lightpaths and wavelengths allocated to ROADMs for the lightpaths required to groom given traffic. The system can also search possible lightpath routes made by ROADMs with specified switch states, and output the total optical losses of the routes. By the new system implemented for the parallel processing, the total time to obtain the results for a 5-node IP-over-CWDM network was reduced down to 65% of the total time by the system with a single machine without parallel processing.
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Congestion removing performance has been investigated in IP-over-CWDM networks with ROADMs under the best-effort transmissions specified by the service level agreement (SLA). Two approaches were tried to remove congestion, and the...
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Congestion removing performance has been investigated in IP-over-CWDM networks with ROADMs under the best-effort transmissions specified by the service level agreement (SLA). Two approaches were tried to remove congestion, and the experimental results clarified that the approaches could remove congestion remotely by adding a lightpath or adding a static bypass route. The degraded throughput was recovered within a recovery time specified by the SLA. As a result, the static bypass route approach can provide fine granularity adjustment of traffic to be switched without lightpath reconfiguration, and the lightpath adding approach can provide effective adjustment of larger traffic than in the static bypass route approach.
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Due to rapid changes of markets and pressures of competitions, industries are adopting their production ways to support diversity of customer's needs and increase of new product developments. This paper deals with development of a...
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Due to rapid changes of markets and pressures of competitions, industries are adopting their production ways to support diversity of customer's needs and increase of new product developments. This paper deals with development of an agent-based architecture of dynamic systems for process planning in the manufacturing systems. In consideration of alternative manufacturing processes and machine tools, the process plans and the schedules of the manufacturing resources are generated incrementally and dynamically. A previously proposed negotiation protocol is customized and improved to generate suitable process plans for the target products real-timely and dynamically, based on the alternative manufacturing processes. The alternative manufacturing processes are presented by the process plan networks and the suitable process plans are searched and generated to cope with both the dynamic status and disturbances of the manufacturing systems. We initiatively combine the heuristic search algorithms of the process plan networks with the negotiation protocols, in order to generate suitable process plans.
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This paper concerns investigation on effective turbulence models for predicting tanker stern flows. Objectives of the present work are twofold: i.e., (1) perform detailed evaluation of two equation models that are, at present, mos...
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This paper concerns investigation on effective turbulence models for predicting tanker stern flows. Objectives of the present work are twofold: i.e., (1) perform detailed evaluation of two equation models that are, at present, most widely accepted in numerical ship hydrodynamics; and (2) investigate feasibility in extending the models for more accurate and efficient mathematical forms. The ad-hoc approach on simple zero or one equation model is not of interest in the present work. Instead, effort will be fully focused on models that offer consistency with flow physics and possibly universal validity. The CFD code used in the present study is FLOWPACK version 2006, which was developed by the authors and its capability has been validated through detailed studies in past years. In particular, three turbulence models are investigated in the present study, i.e., the blending k-ω/k-ε model, the Shear-Stress Transport model, and the near-wall (or low-Reynolds number) modification model. In the following, an overview is given of the present numerical method, and results are presented and discussed for SR196 series tanker and KVLCC2M tanker hull forms including detailed comparisons with available experimental data. Lastly, some concluding remarks are made concerning limitations, requirements, and prognosis for improvements of the present turbulence models.
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Relational data is common in many real-world applications. Linear fuzzy clustering models have been extended for handling relational data based on Fuzzy c-Medoids (FCMdd) framework. In this paper, with the goal being to handle non...
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Relational data is common in many real-world applications. Linear fuzzy clustering models have been extended for handling relational data based on Fuzzy c-Medoids (FCMdd) framework. In this paper, with the goal being to handle non-Euclidean data, β-spread transformation of relational data matrices used in Non-Euclidean-type Relational Fuzzy (NERF) c-means is applied before FCMdd-type linear cluster extraction. β-spread transformation modifies data elements to avoid negative values for clustering criteria of distances between objects and linear prototypes. In numerical experiments, typical features of the proposed approach are demonstrated not only using artificially generated data but also in a document classification task with a document-keyword co-occurrence relation.
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Visualization is a fundamental approach for revealing intrinsic structures in multidimensional observation. This paper considers visualization of non-Euclidean relational data by extracting local linear substructures. In order to ...
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Visualization is a fundamental approach for revealing intrinsic structures in multidimensional observation. This paper considers visualization of non-Euclidean relational data by extracting local linear substructures. In order to extract robust linear clusters, an FCMdd-based linear fuzzy clustering model is applied in conjunction with a robust measure of alternative c-means. Non-Euclidean data matrices are handled with β-spread transformation in a manner similar to that of NERF c-Means. In several experiments, robust feature maps derived by the robust clustering model are compared with feature maps given by the conventional clustering model and Multi-Dimensional Scaling (MDS).
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A multi long-period grating (multi-LPG) sensor was investigated and fabricated by a CO_2 laser for distributed sensing to detect abnormal high temperatures of a nuclear power generator and a large-scale chemical plant. To fabricat...
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A multi long-period grating (multi-LPG) sensor was investigated and fabricated by a CO_2 laser for distributed sensing to detect abnormal high temperatures of a nuclear power generator and a large-scale chemical plant. To fabricate the multi-LPG sensor, a carved LPG was introduced for easy fabrication of the multi-LPGs with different resonant wavelengths in a similar loss spectrum. It was investigated experimentally how the CO_2 laser beam is scanned for the carving. The influence of the irradiated energy of the CO_2 laser on carving has been clarified, and it was found that a minimum irradiated energy of the CO_2 laser existed, and the value was determined to be 0.23 J/mm. As a result, the carved LPG could be fabricated and the resonant wavelength could be shifted successfully for the distributed sensor. The procedures for the fiber carving and the fundamental characteristics of the carving are described in details.
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Our previous study proposed a control law for two-wheeled mobile robots that is based on the synchronization phenomenon of coupled Kuramoto oscillators. The control law aims at achieving circular formation around a given target. W...
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Our previous study proposed a control law for two-wheeled mobile robots that is based on the synchronization phenomenon of coupled Kuramoto oscillators. The control law aims at achieving circular formation around a given target. We must deal with the issue of having robot colliding with potential obstacles while performing the desired encircling behavior, before being able to deploy such a robotic framework. The present report investigates two ways of extending the previous control law into exhibiting obstacle avoidance behaviors. The first possible extension is based on a limit cycle system, whereas the second possible extension is based on the evolution of the desired radius of the circular formation behavior. The control laws are then tested, validated, and compared in a robotic physic-based simulator entitled Gazebo.
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