Study on Process of Construction Planning and its Application

In this paper the planning process based on the network techniques is dealt with for a construction project where the project is defined as a function of sequence among jobs included in the project. The planning process consists of three processes : In the first process the set of alternatives of job sequences which satisfy the restriction for the completion time is obtained by the use of devised branch and bound algorithm. In the second process every kind of performance which is useful for the evaluation of construction project is computed for each alternative and further actual restrictions are established for all performances. In the last process alternatives which satisfy all restrictions are obtained by the filtering procedure and an optimal project is selected from them by a definite criterion. An application of this planning process is shown for the elevated railway construction of the New Sanyo Trunk Line

Hydrogen Permeability of Palladium Membrane for Steam-Reforming of Bio-Ethanol

A Palladium membrane was prepared by electro-less plating method on porous stainless steel. The catalytic hydrogen production by steam-reforming of biomass-derived ethanol (bio-ethanol) using a Pd membrane was analyzed by comparing it with those for the reaction using reagent ethanol (the reference sample). And the hydrogen permeability of the palladium membrane was investigated using the same palladium membrane (H2/He selectivity = 249, at ΔP = 0.10 MPa, 873 K). As a result, for bio-ethanol, deposited carbon had a negative influence on the hydrogen-permeability of the palladium membrane and hydrogen purity. The sulfur content in the bio-ethanol may have promoted carbon deposition. By using a palladium membrane, it was confirmed that H2 yield (%) was increased. It can be attributed that methane was converted from ethanol and produced more hydrogen by steam reforming, due to the in situ removal of hydrogen from the reaction location

Generation of optical Schr\"{o}dinger's cat states by generalized photon subtraction

We propose a high-rate generation method of optical Schr\"{o}dinger's cat states. Thus far, photon subtraction from squeezed vacuum states has been a standard method in cat-state generation, but its constraints on experimental parameters limit the generation rate. In this paper, we consider the state generation by photon number measurement in one mode of arbitrary two-mode Gaussian states, which is a generalization of conventional photon subtraction, and derive the conditions to generate high-fidelity and large-amplitude cat states. Our method relaxes the constraints on experimental parameters, allowing us to optimize them and attain a high generation rate. Supposing realistic experimental conditions, the generation rate of cat states with large amplitudes ($|\alpha| \ge 2)$ can exceed megacounts per second, about $10^3$ to $10^6$ times better than typical rates of conventional photon subtraction. This rate would be improved further by the progress of related technologies. Ability to generate non-Gaussian states at a high rate is important in quantum computing using optical continuous variables, where scalable computing platforms have been demonstrated but preparation of non-Gaussian states of light remains as a challenging task. Our proposal reduces the difficulty of the state preparation and open a way for practical applications in quantum optics.Comment: 8 pages, 5 figure

Faculty Development in the Time of COVID-19: Four Narrative Perspectives

2019年12月発生した新型コロナウイルス感染症はパンデミックに拡大し、世界中の社会・経済、医療現場や日常生活に甚大な影響を及ぼしている。多くの大学でオンラインによる遠隔授業が取り入れられ、本学でもLMS(Learning Management System)や遠隔会議システムを活用し、全額でオンライン授業が実施された。本学のCTE(Center for Teaching Excellence)部門は、オンライン授業実施のための支援に加わり、年間FD研修プログラム等を通して有益な情報共有に取り組んだ。本稿では、FDの取り組みや、オンライン授業の工夫、またそれらを通して教員としてどのような発見や成長があったのか、CTE部門の教員が述べる

Gaussian breeding for encoding a qubit in propagating light

Practical quantum computing requires robust encoding of logical qubits in physical systems to protect fragile quantum information. Currently, the lack of scalability limits the logical encoding in most physical systems, and thus the high scalability of propagating light can be a game changer for realizing a practical quantum computer. However, propagating light also has a drawback: the difficulty of logical encoding due to weak nonlinearity. Here, we propose Gaussian breeding that encodes arbitrary Gottesman-Kitaev-Preskill (GKP) qubits in propagating light. The key idea is the efficient and iterable generation of quantum superpositions by photon detectors, which is the most widely used nonlinear element in quantum propagating light. This formulation makes it possible to systematically create the desired qubits with minimal resources. Our simulations show that GKP qubits above a fault-tolerant threshold, including ``magic states'', can be generated with a high success probability and with a high fidelity exceeding 0.99. This result fills an important missing piece toward practical quantum computing.Comment: 19 pages, 2 figure

Improvement in the neutron beam collimation for application in boron neutron capture therapy of the head and neck region

In June 2020, the Japanese government approved boron neutron capture therapy for the treatment of head and neck cancer. The treatment is usually performed in a single fraction, with the neutron irradiation time being approximately 30–60 min. As neutrons scatter in air and loses its intensity, it is preferable to bring the patient as close to the beam port as possible to shorten the irradiation time. However, this can be a challenge, especially for patients with head and neck cancer, as the shoulders are an obstacle to a clean positioning. In this study, a novel neutron collimation system for an accelerator based neutron source was designed to allow for a more comfortable treatment, without compromising the irradiation time. Experimental measurements confirmed the simulation results and showed the new collimator can reduce the irradiation time by approximately 60% (under the same condition where the distance between the source and the patient surface was kept the same). The dose delivered to the surrounding healthy tissue was reduced with the new collimator, showing a 25% decrease in the D₅₀ of the mucosal membrane. Overall, the use of the newly designed collimator will allow for a more comfortable treatment of the head and neck region, reduce the treatment time, and reduce the dose delivered to the surrounding healthy tissue