In the present study, we consider the air entrainment into a suction pipe which is vertically inserted down into a suction sump across a mean free-water surface. This configuration is often referred to as the “vertical wet-pit pump”, and has many practical advantages in construction, maintenance and operation. In particular, we focus our concern upon the critical submergence depth S_c, which is one of the prime and conventional indicators for the air-entrainment occurrence. By a systematic approach, we experimentally investigate the influences of kinetic and geometric parameters upon S_c. As the kinetic parameters, we consider the Reynolds number Re and the Weber number We, in addition to the Froude number Fr, on such a basis as Fr is not much larger than unity in many actual cases. As the geometric parameters, we consider back clearance X, sump breadth B and bottom clearance Z. Here, all parameters are non-dimensionalised by the outside diameter D and the intake velocity V_i of the suction pipe. As a result, we reveal the effects of such six parameters upon S_c. The We effect, namely, the surface-tension effect can be ignored at We > 12. And, the Re effect, namely, the viscous effect becomes negligibly small at Re > 3×10⁴. Under such conditions for We and Re, we could consider only the Fr effect, namely, the gravitational effect. Concerning the X/D and B/D effects, S_c/D attains the maximum at a certain X/D or B/D. On the other hand, the Z/D effect is monotonic, and becomes small at Z/D > 2.5. Some aspects of these geometric effects can be evaluated by a local-Froude-number effect on the basis of the global relation between S_c/D and Fr. And, the other aspects is necessarily considered to be related with the flow structure in the suction sump.

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The effect of the flow rate and water level on free surface vortices in a suction sump was studied by using numerical simulation. Free surface flow in an intake channel was solved by using finite volume method for RANS equations with k-ω SST turbulence model. A VOF multiphase model and the open channel model were used to solve the multiphase flow in the sump. Minimum position of air-water interface, air-entrained vortex length, air volume fraction contours and iso-surfaces were used to identify visually the location and shape of the free surface as well as surface vortices. From the numerical investigation with varying flow rate and water level, it was found that when the water level decreased or the flow rate increased, more free surface vortices appeared. The predicted velocity distributions at the entrance of bell mouth and the location of the center core of air-entrained vortices on the free surface were in good agreement with experimental results.

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Our aim is to understand the air entrainment into a suction pipe inside a suction sump in the vertical-wet-pit-pump configuration. This suction-sump flow accompanying the air entrainment often appears in various industrial and environmental problems, however is usually complicated owing to both their unsteadiness with poor periodicity and their fully-three-dimensionality. In the present study, we investigate the influences of governing parameters upon the occurrence-time ratio γ of the air entrainment using a bubble sensor.

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In the present study, we consider the air entrainment into a suction pipe which is vertically inserted down into a suction sump across a mean free-water surface. This configuration is often referred to as the “vertical wet-pit pump”, and has many practical advantages in construction, maintenance and operation. In particular, we focus our concern upon the critical submergence depth S_c, which is one of the prime and conventional indicators for the air-entrainment occurrence. By a systematic approach, we experimentally investigate the influences of kinetic and geometric parameters upon S_c. As the kinetic parameters, we consider the Reynolds number Re and the Weber number We, in addition to the Froude number Fr, on such a basis as Fr is not much larger than unity in many actual cases. As the geometric parameters, we consider back clearance X, sump breadth B and bottom clearance Z. All these parameters are non-dimensionalised by the outside diameter D and the intake velocity V_i of the suction pipe. As a result, we reveal the effects of such six parameters upon S_c. The We effect, namely, the surface-tension effect can be ignored at We > 12. And, the Re effect, namely, the viscous effect becomes negligibly small at Re > 3×10⁴. Under such conditions for We and Re, we could consider only the Fr effect, namely, the gravitational effect. Concerning the X/D and B/D effects, S_c/D attains the maximum at a certain X/D or B/D. On the other hand, the Z/D effect is monotonical, and becomes small at Z/D > 2.5. Some aspects of these geometric effects can be evaluated by a local-Froude-number effect on the basis of the global relation between S_c/D and Fr. And, the other aspects is necessarily considered to be related with the flow structure in the suction sump.

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ポンプの入口流れは吸込水槽の形状に依存する．ポンプを安定した状態で運転するために，吸込水槽内に発生した有害な渦を極力抑えることは，ポンプ設計上又は運転上の重要な課題となっている。本報では、国内外模型試験及びCFDによるポンプ吸込み水槽内の空気吸込み渦と水中渦の可視化について紹介する。TSJ基準による国内の模型試験では，渦発生の有無を目視で判定することが定められていることに対して，HI基準による海外の模型試験では，肉眼で確認できる程度の渦は発生しにくくなるため，染料を用いて渦を可視化する．一方， CFDによる渦の予測が近年多く試みられている．RANSによる定常解析は，現実的な計算コストを踏まえた格子分割数で検討できるため，実績が多い．LESによる非定常解析は実用レベルになりつつあるが、まだ実績が少ない．

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56 unipolar VVI pacemakers were tested by 4 ways of inhibition test—hand grip, back strength, sitting up and push up test. Filter characteristics of Siemens-Elema 668 generator was examined by sin² pulse wave.
Pacemaker inhibition was observed in 34 of 56 (60.7%). Among 4 tests, inhibition occurred most frequent in push up test related to a great pectral muscle and less frequent in the patients with the generators in an abdominal wall as compared with a great pectral muscle area.
Suggestions for avoidance of myopotential inhibition are as follows: (1) Pulse generators which are more sensitive than 1.5mV should not be used unless there is a specific problem. (2) A pulse generator should be placed in a subcutaneous abdominal wall pocket. ()Usage of a bipolar system. (4) Convert to a fixed rate or a ventricular synchronous unit. (5) Usage of a multiprogrammable pacemaker.

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In pump’s sumps, the air entrainment sometimes occurs. Such flow accompanying the air entrainment becomes complicated owing to both of its unsteadiness with poor periodicity and its fully-three-dimensionality. In various industrial and environmental problems, the air entrainment often induces vibration, noise, low pumping efficiency or pump’s collapse at the worst, and is usually complicated owing to both their unsteadiness with poor periodicity and their fully-three-dimensionality. The present aim is to understand the air entrainment into a suction pipe, which appears inside a simple and basic suction sump in the vertical-wet-pit-pump configuration. In particular, we focus upon the influences of governing parameters upon the occurrence-time ratio γ of the air entrainment in over-critical-submergence condition, using a conductance-type electric sensor which can detect the existence of air bubbles through a suction pipe with no disturbances by the sensor probe and with a fine spatial resolution in order to achieve accurate measurements. As a result, we reveal the influences of such three kinetic parameters as the Froude number, the Reynolds number and the Weber number (or the Bond number) together with four geometric parameters upon the air entrainment and the free-surface pattern inside the suction sump.

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Reovirus isolates from human, striped-field mouse (Apodemus agrarius) and Korean field mouse (A. peninsulae) in Korea showed extensive variability in the patterns of electrophoretic migration of the double-stranded RNA (dsRNA) genome segments. Hemagglutination inhibition (HI) test was performed for serotype determination of 12 reovirus isolates. To clarify genetic diversity and molecular phylogeny of Korean reoviruses, L1, S3 and S4 genomic segments of reoviruses were amplified by RT-PCR and directly sequenced. Among 12 reovirus strains, 9 strains were type 3 and 3 strains were type 2. The L1 was highly conserved showing 91.5-100%, 94.7-100% similar ities among Korean isolates, and 77.5-97.9%, 92.6-96.8% similarities compared to other reference strains of each genotypes at nucleotide and amino acid levels, respectively. In S3 and S4 segments, 84.4-99.3%, 72.3-99% nucleotide sequence similarities and 92-99.3%, 89.1-98.4% amino acid sequence similarities among Korean isolates were observed, and 70.8-93.9%, 72.3-98.7% nucleotide sequence similarities and 81.8-100%, 88.3-97.7% amino acid sequence similarities compared with other reference strains of each genotype were observed, respectively. Phylogenetic analyses based on the S3 and S4 nucleotide sequences indicate that genotypes of reovirus are more related with geographic differences rather than host species or date of isolation.

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Our aim is to understand the air entrainment into a suction pipe inside a suction sump in the vertical-wet-pit-pump configuration. This suction-sump flow accompanying the air entrainment often appears in various industrial and environmental problems, however is usually complicated owing to both its unsteadiness with poor periodicity and its fully-three-dimensionality. In the present study, from a viewpoint of the self-organised criticality (SOC), we conduct long-term measurements with a fine time resolution of 0.1 s using a CdS optical cell. As a result, the air entrainment is classified into two; one with short lifetime and the other with long lifetime. It is suggested that the latter is possibly related with SOC.

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A monoclonal type M-immunoglobulin (IgM) was generated in mice against a nuclease-urea extract of HeLa metaphase chromosomes. This antibody stains metaphase chromosomes from a variety of mammalian cultured cell types by indirect immunofluorescence. Antibody 12C7 reacts by western transfer technique with histone H1 in all the cell lines tested. The antibody cross-reacts with H1, and H1⁰ in human cells. Proteolytic digestions of H1 suggest that the epitope is localized in the carboxy-terminal domain of the histone H1 molecule. Digestion with trypsin demonstrates that the antibody 12C7 does not react with the globular domain of histone H1. The C-terminal domain of H1 subtypes therefore seems to have a conserved determinant which does exist in H1, H1⁰, and probably in H5. This antibody has applications in studying the role of that domain of H1 in processes like chromosome condensation and variations in chromatin structure which influence gene expression.

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画像にBGMを付けることで印象をより強めることができるが,画像の印象にマッチした楽曲を自動的に推薦する手法はいまだ確立されていない.本研究では,正準相関分析を用いることで画像と楽曲の主観的な対応関係を学習し画像にマッチする楽曲を自動で推薦する手法について検討する.

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