Flow simulation for a waxy crude that is Bingham-plastic in nature has been performed for pipeline . In this paper, the methodology used for temperature, pressure and velocity profile prediction will be discussed. The possibility of restarting the cold gelled fluid and the required time for flow to reach steady state have also been investigated.

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The is one of the typical environmental diversity techniques in dependable computing, and is quite effective to rejuvenate software systems at low cost. In this paper we generalize the seminal results on mechanisms by van Moorsel and Wolter (2004, 2006) and analyze optimal policies under more general conditions. We further develop a statistical algorithm to estimate the optimal policies from the empirical data of task processing time.

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DNA-protein crosslinks (DPCs) generated by radiation and other genotoxic ‎chemicals are formidable obstacles to DNA replication and transcription, and ‎their persistence would lead to mutations and cell death. Thus, the repair or ‎tolerance of DPCs is essential for cells. Recently, we have shown that ‎nucleotide excision repair (NER) and homologous recombination (HR) are ‎involved in the repair and tolerance of DPCs, yet much remains to be learned ‎about how cells deal with these superbulky lesions. In this work, we utilized a ‎genetic approach to obtain further insight into the mechanistic aspects of NER ‎and HR of DPCs and to assess the roles of other repair mechanisms such as ‎base excision repair (BER) and translesion synthesis (TLS). We measured ‎the sensitivities of a panel of E. coli mutants to DPCs-inducing agents ‎including formaldehyde (FA) and 5-azacytidine (azaC). The priA mutant ‎displayed a marked sensitivity to FA and azaC, indicating a crucial role of the ‎PriA helicase in the of stalled replication forks following HR. In ‎contrast, other helicase mutants including priB, priC, and rep showed no to ‎only marginal sensitivities. The mutants of recJ and recQ which are involved ‎in the RecFOR-dependent HR pathway also showed marginal sensitivities to ‎FA and azaC. This observation is consistent with our previous finding that the ‎HR of DPCs proceeds exclusively through the RecBCD pathway. With respect ‎to TLS polymerase mutants, polB, dinB, and umuDC exhibited no sensitivity ‎to FA and azaC, eliminating their role in tolerance of DPCs. Regarding to the ‎excision repair, the mutant deficient in the Cho endonulease (a UvrC ‎homolog) showed moderate sensitivity to FA, suggesting a role of Cho in the ‎excision of DPCs. The mutants of TCR (mfd) and BER (nth/nei and xth/nfo) ‎were not sensitive to both DPC-inducing agents. The present study further ‎confirms the critical role of NER and HR and eliminates the roles of BER and ‎TLS in the repair and tolerance of DPCs. ‎

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It was announced that JRR-3 will resume its operation at the end of February, 2021. Neutron community has strongly anticipated resume of JRR-3 for a decade. Neutron sciences at JRR-3 have been suspended since March, 2011. There are numbers of problems piled during the past 10 years, and we are facing to overcome them before resume of JRR-3. On the occasion of the 30th anniversary of Hamon and JRR-3, this article overviews the history of JRR-3 and forecasts the future of JRR-3.

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Due to a recent event at pressurized water reactor (PWR), the impact of a loss of shutdown cooling during reduced RCS inventory conditions was evaluated. The evaluation for the loss of RHRS assumed loss of shutdown cooling initially and then the RHRS pumps were restored. This analysis is based upon a decay heat rate corresponding to 2.66 days following reactor shutdown with an initial liquid level at the elevation of the reactor flange. When the RHRS pump was restored, the calculation revealed that a void fraction of 10 -50 % could exist in the hot leg pipe where the RHRS pumps take suction. The study presented in this paper was conducted to determine the maximum voids permissible in the hot leg piping and still ensure that the water entering the RHRS pump did not have steam voids. RELAP5 was used to perform this evaluation. RELAP5/M3.3 is a computer code used for the thermal-hydraulic analysis of transients and small-break accidents and transients in light-water nuclear power plants. It uses a one-dimensional, two-fluid model, consisting of steam and water, with the possibility of the vapor phase containing a non-condensable component. A model of the piping was developed and the conditions presented above were analyzed and the fluid conditions were reviewed. The results of the RELAP5 analyses indicated that for voids 30 % or less in the hot leg, the RHRS pump would have adequate suction flow to remain in a stable operational condition.

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Modern FPGAs have been integrated in computing systems as accelerators for long running applications. This integration puts more pressure on the fault tolerance of computing systems, and the requirement for dependability becomes essential. As in the case of CPU-based system, checkpoint/

techniques are also expected to improve the dependability of FPGA-based computing. Three issues arise in this situation: how to checkpoint and FPGAs, how well this checkpoint/ model works with the checkpoint/ model of the whole computing system, and how to build the model by a software tool. In this paper, we first present a new checkpoint/ architecture along with a checkpointing mechanism on FPGAs. We then propose a method to capture consistent snapshots of FPGA and the rest of the computing system. Third, we provide “fine-grained” management for checkpointing to reduce performance degradation. For the host CPU, we also provide a stack which includes API functions to manage checkpoint/ procedures on FPGAs. Fourth, we present a Python-based tool to insert checkpointing infrastructure. Experimental results show that the checkpointing architecture causes less than 10% maximum clock frequency degradation, low checkpointing latencies, small memory footprints, and small increases in power consumption, while the LUT overhead varies from 17.98% (Dijkstra) to 160.67% (Matrix Multiplication).

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In Hirono town, Iwate prefecture, the wave-cut bench area which was above sea level only at low tide was developed to nursery for abalone and sea urchin. As a result of the promotion of sea farming, the nursery has become major source of income in the town. However, the nursery was seriously damaged by the Great East Japan Earthquake and Tsunami. Sea urchin is one of the specialties of the town. Therefore, all the parties concerned made efforts to of sea urchin farming in nursery. By their efforts, 1) the restoration of the nursery, 2) the of sea urchin transplantation and fishing, 3) the of seedling production of juvenile sea urchin and 4) the of sea urchin direct-sales had been done in some months after the earthquake. Now, it passed for 3 years and 10 mounts after the earthquake. of nursery in Hirono town went well. However, we still have some problems. For example, finding un-recovered areas and recovering abalone and sea urchin resources will take some years. Ageing and depopulation of local fishermen are also the problems. To assess the influence of the earthquake early, monitoring is effective. It is necessity to continue the survey for assessment of recovery from damages of the earthquake.

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To solve the two significant problems of climate change and energy security, Japanese Government decided the promotion of new construction of innovative nuclear power plants (NPPs) at the stations that existing reactors are decided to be decommissioned. Public opinion on nuclear energy is an important factor in building support for new construction of NPPs. In this study, opinion surveys on the of existing NPPs, new construction of NPPs, and new construction of NPPs that no longer require evacuation were conducted at municipalities with NPPs, neighbor municipalities, and nationwide in Japan. Little difference among three groups is observed. New construction of NPPs that no longer require evacuation got more support than new construction of NPPs. In municipalities with NPPs and neighbor municipalities, it was found that majority of respondents had little knowledge of evacuation plans and had little experience participating in evacuation drills. One quarter of the respondents do not accept evacuation at all. To take into account this residents’ opinion and to strengthen Defense-in-Depth from existing NPPs, performance objective of new NPPs should aim to no longer require evacuation. Based on these findings, this research provides valuable insights that can help advance nuclear energy policy in Japan.

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The flow mechanism on transient unstart and phenomena due to compound choking and/or disturbances in the combustion chamber of a scramjet engine were investigated experimentally and numerically. Experiment is conducted by using a Mach 3 blowdown tunnel. Engine unstart was initiated by blowing jet from the top surface of engine model. Shock movements in transient conditions were captured by 5 pressure transducers capable of 20kHz sampling and by optical measurements. The results were compared with numerical results which were performed by a quasi-three dimensional MacCormack differential scheme. Both results coincide qualitatively, and it is shown that the mechanisms of the transition from start to unstart in sheared inflow with boundary layer flow is different from that in uniform inflow. Namely, whole flow is dammed up by disturbance on unstart of uniform inflow, on the other hand in sheared inflow case shock waves arise first in boundary layer flow and pressurized boundary layer at the back of the shock pushes out the main flow. It is also found that the transition unstart is accompanied by movement of stronger shock waves than transient and the behavior of the shock waves is quite different between the transient unstart and .

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An efficient recovery method for thread-level speculation (TLS) is proposed. The method tracks the inter-thread data dependence as a method for identifying those threads that are obviously unaffected by a data dependence violation. The method is simple to implement. Still, the simulation results using benchmark applications show that the method can significantly reduce the number of unnecessary thread restarts and consequently improve the performance of TLS. Specifically, when compared with the baseline TLS, TLS with the proposed method is 2.3 times faster for IS, 1.7 times faster for equake, and 3.5 times faster for mcf with the use of 64 cores. With the method, the performance of TLS increases steadily up to 64 cores for IS, equake, and mcf, while the speedup of the baseline TLS starts to saturate at 8 or 16 cores.

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Recently, the pseudo-transient analysis (PTA) methods have been researched as one of the most effective continuation methods to overcome the non-convergence problem of the Newton-Raphson method for finding the DC operating points of nonlinear circuits. However, the former PTA methods have a time-consuming problem, especially for some large-scale circuits. In this paper, we combine an effective ramping algorithm with two proposed ramping functions and the damped PTA (DPTA) algorithm together to improve the simulation efficiency. It can eliminate the oscillation and time-consuming problems at the same time. Besides, a method in the SPICE3 implementation is also proposed, which is effectively to improve convergence when the circuit is stuck in an infinite loop and fails to converge during the simulation. Numerical examples demonstrate the efficiency and convergence improvement of the proposed algorithms.

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Hog1 of Saccharomyces cerevisiae is activated by hyperosmotic stress, and this leads to cell-cycle delay in G₁, but the mechanism by which cells from G₁ delay remains elusive. We found that Whi3, a negative regulator of G₁ cyclin, counteracted Hog1 in the from G₁ delay caused by osmotic stress. We have found that phosphorylation of Ser-568 in Whi3 by RAS/cAMP-dependent protein kinase (PKA) plays an inhibitory role in Whi3 function. In this study we found that the phosphomimetic Whi3 S568D mutant, like the Δwhi3 strain, slightly suppressed G₁ delay of Δhog1 cells under osmotic stress conditions, whereas the non-phosphorylatable S568A mutation of Whi3 caused prolonged G₁ arrest of Δhog1 cells. These results indicate that Hog1 activity is required for from G₁ arrest under osmotic stress conditions, whereas Whi3 acts as a negative regulator for this mechanism.

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This paper presents an approach for improving the efficiency of solving linear systems by applying a genetic algorithm (GA) to the GMRES(m) method. For every process in GMRES(m), the initial vectors are regarded as chromosomes. When the process stagnates, the GA performs a crossover on chromosomes to create new chromosomes for the next stage, in which a weighted average algorithm is used to perform the crossover process effectively. To further enhance the performance, the concept of “chromosome-wide stagnation” is introduced by enabling on-the-fly detection of a slowdown in convergence of the GA. A possible way to adjust the m value automatically at the onset of such stagnation is proposed. The proposed method had been tested on several sample matrices and showed satisfactory improvements in execution time.

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In order to increase the production rates and to secure the base production technology for the hard casting materials, a - casting technology as an active curing methodology has been developed to reduce the number of sticking type breakouts in the thin slab caster with high speed. It consists of the healing casting conditions of breakouts, the mold level control method for preventing the overflow or big change of molten steel near meniscus and the control of cooling rate at second cooling zone for rolling under the limits of rolling force and torque at the directly linked roughing mill. By applying the proposed technology, the automatic restarting rate of breakout is remarkably increased from 0 to 92%.

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A permanent magnet synchronous motor (PMSM) rotational angle sensorless control system can have a problem with restarting when coasting. A coasting method has been proposed that uses the information of the three-phase short circuit current. However the coasting conditions of the one-time three-phase short circuit method have not been revealed. This study examined the conditions for a rotational angle sensorless PMSM when coasting. In the experimental tests, the duration of the three-phase short circuit was varied to examine its effect on the estimated rotor angle and rotor speed. The experimental test results were numerically analyzed to quantify the effect of the short circuit duration, because the error was caused by linearization of the estimation equation. We propose an enhanced method that considers the time response of the three-phase short circuit current. The proposed method was verified experimentally.

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An outbreak of foot-and-mouth disease (FMD) occurred in Miyazaki Prefecture, Japan, in 2010. This epidemic was controlled with culling and vaccination, and resulted in the death of nearly 290,000 animals. This paper describes the factors associated with hesitation to

farming after the epidemic. A questionnaire survey was conducted to assess the mental health of farmers one year after the end of the FMD epidemic in affected areas, and univariate and multivariable analyses were performed. Of 773 farms which had answered the question about farming, 55.4% (428/773) had resumed or were planning to resume operation. The farms hesitated restarting were characterized by small scale (P=0.06) and having multiple sources of income (P<0.01). Personal attributes associated with hesitation to were advanced age of the owner (P<0.01), with someone with bad physical conditions (P=0.04) and small family size (P<0.01). Factors related to disease control during the epidemic that were associated with hesitation to were vaccination of animals (P<0.01), not assisting with culling on other farms (P<0.01), and higher satisfaction with information provided by the government (P=0.02). We found that farmers hesitated to resume farming because they had a limited labor force, had an alternative business or were mentally distressed during disease control.

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