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In the design process of a steam generator, a porous-media-approach computational code is utilized for simulating three-dimensional two-phase flow behavior in the secondary side of steam generators...

Sloshing is a motion of free liquid surface in a tank, which is caused by strong seismic waves with long period components. Sloshing with large amplitude causes damage to the tank roof. In our previous study, a method was proposed to evaluate vertical load acting on a roof of cylindrical tank due to collision of sloshing liquid surface. The method is a combination of the pressure model based on Wagner’s model and the simplified nonlinear sloshing model that calculates liquid surface shape and velocity. But, the method tends to underestimate the vertical load when roof height is high and overestimate when it is low. In this study, a new method is proposed to evaluate vertical load acting on a roof of cylindrical tank. This proposed method is constructed by a new pressure model, a new nonlinear sloshing liquid surface model, and a new local liquid surface wave model. Its pressure model is developed by applying the pressure model of two-dimensional flat plate surface to the circumferential wetted region of the roof. Its nonlinear sloshing liquid surface model is developed by adding higher order radial modes of liquid surface shape. Its local liquid surface wave model is developed by considering a nonlinear local liquid surface behavior induced by roof collision.

When discussing the reliability of backsheet of PV modules, it is important to accurately determine the amount of stress it receives. In this study, the UV irradiation dosage on the back side of a rack-mounted module, which has been estimated from multiplication of the UV irradiation dosage on the front side and the UV albedo, was actually measured. It was found that the measured value was 1.4 kW h/m2/y, which was almost 1/3 of the estimated value of 4.2 kW h/m2/y. The environmental stress on the back side of the PV module was also investigated by comparing changes in the molecular weight distribution of transparent poly(ethylene terephthalate) films subjected to outdoor exposure or indoor acceleration test. It is shown that UV and hygrothermal stress can be separated by analysis of the molecular weight distribution peak height and shift so that the extent of UV dose in fielded modules can be estimated. It was found that the stress on the back side of the PV module, exposed for 5.5 years using asphalt with 6% UV albedo as the flooring material, was close to that of 8 kW h/m2 after a UV irradiation test, a subsequent 6 h pressure cooker test, or a subsequent 200 h damp heat test. Acceleration tests that reproduce stress itself rather than deterioration phenomena should be developed, and for that, it is important to measure the amount of stress in various cases with reference to this measurement and separation method of stress.

When a cylindrical tank installed on the ground, such as an oil tank or a liquid storage tank, receives strong seismic waves, including a long-period component, motion of free liquid surface inside a tank called sloshing may occur. If high-amplitude sloshing occurs and waves of free liquid surface collide with tank roof, it may lead to accidents such as damage to tank roof or outflow of internal liquid. There is also a possibility that tank sidewall may be damaged due to fluid force generated by high liquid surface level of sloshing. When sloshing wave height is small, liquid surface level and velocity can be calculated based on the linear velocity potential theory. When sloshing wave height increases, sloshing becomes nonlinear, and the difference between actual value and calculated value based on the linear velocity potential theory increases. Sloshing loads acting on roof and sidewall should be evaluated in consideration of nonlinear sloshing. In the previous study, simplified equations of nonlinear liquid surface shape and nonlinear liquid surface velocity distribution were proposed, as input parameters of evaluating sloshing loads. In this paper, a new method is proposed for nonlinear sloshing condition of cylindrical tanks, which can evaluate the vertical load acting on roof and the horizontal load acting on sidewall. In the proposed method, new pressure models modified from existing models are combined with simplified equations of nonlinear liquid surface shape and nonlinear liquid surface velocity distribution proposed in the previous study. A long calculation time as CFD analysis is not needed, because the proposed method is consisted of simplified equations.

Background Recent treatment for food allergies involves the intake of allergy-causing foods at doses lower than the threshold dose determined by the oral food challenge (OFC). For a more successful treatment, it is necessary to identify a biomarker to establish safer doses of allergens in foods consumed at home. Objective In this study, we aim to investigate whether the pattern of sensitization to cow's milk (CM) is related to the threshold dose of CM. Methods Fifty patients with sensitization to casein (casein-specific IgE titer ≥ 0.7 UA/ml) and who have undergone the CM OFC test from July 2013 to July 2015 were enrolled. They were examined for the presence or absence of sensitization to β-lactoglobulin (BLG) (BLG-specific IgE ≥ 0.7 UA/ml). They were divided into two groups, namely, the only-casein-specific IgE-positive (C) group, and both casein- and BLG-specific IgE-positive (C + B) group. Results The C group had 26 patients and the C + B group had 24. Both the CM- and casein-specific IgE titers were higher in the C + B group than in the C group. The positivity rates determined from OFC test results were 53.8 and 87.5%, and the threshold doses of CM were 88.7 and 31.1 ml in the C and C + B groups, respectively. In patients with low casein-specific IgE titers (≤ 10 UA/ml), the C + B group showed a significantly lower threshold dose of CM than the C group. Conclusions Our results suggest that children with CM allergy sensitized to casein alone have a higher threshold dose than those sensitized to both casein and BLG.

Recently, tube-to-tube wear indications of triangular tube bundle steam generators (SGs) caused by fluidelastic instability (FEI) in the in-plane direction of U-bend region (in-plane FEI) have been reported. Several experiments were conducted to investigate the characteristics of in-plane FEI by our research groups. In a series of experiments, particular characteristics of in-plane FEI were found. For example, there are the critical velocity difference between the in-plane and the out-of-plane directions, the difference between straight tube bundle tests and U-bend tube bundle tests, etc. To explain these characteristics, unsteady fluid force acting on tubes were measured. The experimental investigation was conducted under high temperature and high-pressure steam–water flow conditions close to the SGs. Stability analyses were conducted using the measured unsteady fluid forces as inputs. First, stability analyses were done to simulate straight tube bundle tests. Analysis results agreed well with experiments and it could explain the effect on critical velocity trend by number of flexible tubes and directions of vibration. Second, U-tube stability analyses were performed by applying unsteady fluid force coefficients for each location of U-bend tube finite element method (FEM) model. From the results, mechanisms of in-plane FEI were understood.

When cylindrical tanks installed in the ground, such as oil tanks and liquid storage tanks, receive strong seismic waves, including the long-period component, motion of the free liquid surface inside the tank called sloshing may occur. If high-amplitude sloshing occurs and the waves collide with the tank roof, it may lead to accidents such as damage of the tank roof or outflow of internal liquid of the Tank. Therefore, it is important to predict the wave height of sloshing generated by earthquake motions. Sloshing is a type of vibration of free liquid surface, and if the sloshing wave height is small, it can be approximated with a linear vibration model. In this case, the velocity-response-spectrum method using velocity potential can estimate the sloshing wave height under earthquake motions. However, if the sloshing wave height increases, the sloshing becomes nonlinear, and necessary to evaluate the wave height using other methods such as numerical analysis. Design earthquake magnitude levels in Japan tend to increase in recent years, long-period components of earthquake wave which act on the sloshing wave height also increase instead of introducing seismic isolation mechanisms. To evaluate load acting on the internal components of cylindrical tanks by nonlinear sloshing, there are few applications which quantitatively evaluated the crest impact load of nonlinear sloshing. In order to evaluate the load acting on the internal components of cylindrical tanks, the range of applicability of the fluid flow analysis method which validated the analysis accuracy of impact load acting on the roof in a simple cylindrical tank in the past study (PVP2019-93442) is extended to cylindrical tanks with internal components.

When cylindrical tanks installed in the ground, such as oil tanks and liquid storage tanks, receive strong seismic waves, including the long-period component, motion of the liquid surface inside the tank called sloshing may occur. If large-amplitude sloshing occurs and the waves collide with the tank roof, it may lead to accidents such as damage of the tank roof or outflow of internal liquid of the tank. Also, there is a possibility that the internal components in the tank may be damaged due to the fluid force generated by the flow of the sloshing. In order to evaluate the load acting on the tank roof, it is considered that the liquid surface shape and the liquid surface velocity are required as input parameters. In order to evaluate the load acting on the internal component in the tank, the flow velocity generated by sloshing is required as an input parameter. If the sloshing wave height is small, these values can be calculated based on the linear potential theory. However, when the sloshing wave height increases, the sloshing becomes nonlinear, and the difference between the nonlinear sloshing behavior and the linear sloshing behavior. Therefore, the method of evaluating nonlinear sloshing behavior is necessary to evaluate the design load of tank under the large sloshing wave height condition. In this paper, new methods of evaluating nonlinear sloshing behavior are proposed for the first-order sloshing mode of a cylindrical tank, which can evaluate the maximum nonlinear sloshing wave height, the nonlinear liquid surface shape, the liquid surface velocity, and the flow velocity. Proposed methods, which consist of simplified equations, are expected to be applied to a new sloshing load evaluation method in primary design.1

Methylcellulose (MC) is one of the widely used bio-based polymers derived from cellulose. MC possesses an amphiphilic property, since it contains both the hydrophilic hydroxyl group and the hydrophobic methoxy group in its molecular structure. Due to the amphiphilicity, aqueous MC solution shows temperature-sensitive property i.e. the lower critical solution temperature (LCST) type of phase behavior. On the other hand, a special organic salt, sodium tetraphenylborate (NaBPh 4 ) also possesses an amphiphilic property, since it consists of hydrophilic cation Na + and hydrophobic anion BPh 4 − . Motivated by an interest in the combined effect of the dual amphiphilicity, here we studied the addition effects of NaBPh 4 on the cloud point of aqueous MC. When the additive amount of NaBPh 4 to aqueous MC was small, the cloud point was depressed with the amount of NaBPh 4 , namely the salting-out effect. However, when the additive amount of NaBPh 4 exceeded a certain value, the cloud point was elevated drastically with the amount of NaBPh 4 , namely the salting-in effect. We proposed a hypothesis that the switching from the salting-out to the salting-in is caused by concentration-specific binding of NaBPh 4 to MC; NaBPh 4 mostly dissociates into Na + and BPh 4 − acting as the salting-out salt when the concentration of NaBPh 4 is small, whereas the hydrophobic anions BPh 4 − are bound to the hydrophobic region of MC acting like a surfactant when the concentration of NaBPh 4 exceeds a critical value. The presence of such a concentration-specific binding of anions was confirmed by the electric conductivity measurements.

The in-plane (in-flow) fluid-elastic instability (in-plane FEI) of triangular tube arrays caused tube-to-tube wear indications as observed in the U-bend regions of tube bundles of the San Onofre Unit-3 steam generators[1]. Several researches revealed that the in-plane FEI is likely to occur in a tightly packed triangular tube array under high velocity and low friction conditions, while it is not likely to occur in a square array tube bundle. In order to confirm the potential of steam-wise fluid-elastic instability of square arrays, the critical flow velocity in two-phase flow, (sulfur hexafluoride-ethanol) which simulates steam-water flow, was investigated. Two types of test rigs were prepared to confirm the effect of the tube diameter and tube pitch ratio on the critical velocity. In both rigs, vibration amplitudes were measured in both in-flow and out-of-flow directions in various flow conditions. In any case, in-flow fluid elastic instability was not detected. Based on the results of the tests, it is concluded that the flow interaction force is small for concern to occur the fluid-elastic instability in the in-flow direction of the square tube bundles of steam generators.

The in-plane (stream-wise) fluid-elastic instability of triangular tube arrays caused tube-to-tube wear indications as observed in the U-bend regions of tube the bundles of San Onofre Unit-3 steam generators. To understand the in-plane FEI characteristics, stability analysis using unsteady fluid forces is quite helpful. However, taking measurements of unsteady fluid forces in the in-plane direction is quite challenging as the fluid coupling forces of the surrounding tubes must be measured simultaneously for the in-plane stability analysis. In particular, taking measurements under a high pressure and high temperature steam-water conditions, similar to an SG operating condition, is extremely difficult. Recently we have been able to successfully measure unsteady fluid force using a specially designed test equipment. In the meantime, random excitation forces acting on heat transfer tubes were also measured. We calculated the stability boundary of the in-plane FEI using the unsteady fluid force measurement with this special equipment.

A considerable amount of time and dedication have been devoted into the development of an unified non-dimensional random excitation forces (Power Spectrum Density) PSD model of tube bundles into two phase flow conditions. However, any model cannot be used for wide-range two phase flow conditions as random excitation forces depends strongly on a two phase flow regime. Therefore, we have developed a new scaling method for a two phase random excitation force PSD to be applicable for a wide-range of flow conditions. This method has been developed by focusing on the correlation between a two phase pressure loss and two phase turbulence energy. Comparisons of non-dimensional random excitation force PSDs in various conditions scaled by using the developed method, showed a good concordance between the two.

When cylindrical tanks installed on the ground, such as oil tanks and liquid storage tanks, receive strong seismic waves, including the long-period component, motion of the free liquid surface inside the tank called sloshing may occur. If high-amplitude sloshing occurs and the waves collide with the tank roof, it may lead to accidents such as damage of the tank roof or outflow of internal liquid of the tank. Therefore, it is important to predict the wave height of sloshing generated by earthquake motion. Sloshing is a type of vibration of free liquid surface, and if the sloshing wave height is small, it can be approximated with a linear vibration model. In this case, the velocity-response-spectrum method using velocity potential can estimate the sloshing wave height under earthquake motion. However, if the sloshing wave height increases, the sloshing becomes nonlinear, and necessary to evaluate the wave height using other methods such as numerical analysis. Design earthquake magnitude levels in Japan tend to increase in recent years, long-period components of earthquake wave which act on the sloshing wave height also increase instead of introducing seismic isolation mechanisms. To evaluate sloshing wave crest impact load acting on the roof of a tank, there are few applications which quantitatively evaluated the crest impact load of nonlinear sloshing. To construct a simple technique to evaluate the sloshing impact load considering the nonlinear sloshing wave height which acts on a flat roof of cylindrical tanks, it is proposed that flow diagram of evaluating the sloshing impact load which newly took into consideration the nonlinearity of sloshing and the dynamic amplification factor. The applicability of the technique was verified with the shaking table tests results for cylindrical tank and flow-analysis results.

The reactor coolant pump (RCP) in a pressurized water reactor (PWR) plant generates pressure pulsations at multiple frequencies. These pressure pulsations excite the acoustic modes inside the reactor vessel (RV), and cause significant acoustic loads on the reactor internals (RIs). For verifying the structural integrity of the RIs, it is important to predict the acoustic loads, which is used for vibration analysis of the RIs. Traditionally, an analytical method, assuming that structures are rigid, has been used in order to predict the acoustic pressure distributions inside the RV [1]. However, water in actual PWR plant is heavy enough to influence structural response, so that it is required to use methods for a coupled structural acoustic system. In this article, the coupled structural-acoustic analysis using the commercial software ANSYS is proposed in order to predict the acoustic loads, and the applicability of this method is discussed. The structural-acoustic interactions inside the RV are investigated by element tests and the scale model test. The acoustic pressures measured by these tests are compared with the calculated results.

When cylindrical tanks installed on the ground, such as oil tanks and liquid storage tanks, receive strong seismic waves, including the long-period component, motion of the free liquid surface inside the tank called sloshing may occur. If high-amplitude sloshing occurs and the waves collide with the tank roof, it may lead to accidents such as damage to the tank roof or outflow of internal liquid. Therefore, it is important to predict the wave height of sloshing generated by an earthquake input. Sloshing is vibration of the free liquid surface, and when the sloshing wave height is small, it can be approximated with a linear vibration model. In that case, the velocity-response-spectrum method using velocity potential can estimate the sloshing wave height under an earthquake input. However, when the sloshing wave height increases and the sloshing becomes nonlinear, it is necessary to evaluate the wave height using other methods such as numerical analysis. Taking into consideration that design earthquake levels tend to increase and the use of seismic isolation mechanisms has continued to spread in recent years, the amplitude of the long-period components of an earthquake input which act on cylindrical tanks may also increase. Therefore, although the evaluation of nonlinear sloshing wave height is important, there are few examples which quantitatively evaluate the wave height of nonlinear sloshing. The purpose of this study is to construct a simple evaluation technique of a nonlinear sloshing wave height of cylindrical tanks. In this study, the simple evaluation technique of the nonlinear sloshing wave height was proposed based on the study result shown by the 1st report (PVP2018-84416). Moreover, in order to verify the applicability of the proposed evaluation technique, the shaking table test and flow analysis which used the small cylindrical tank were carried out. As a result, the applicability of the proposed evaluation technique has been verified.

When cylindrical tanks installed on the ground, such as oil tanks and liquid storage tanks, receive strong seismic waves, including the long-period component, motion of the free liquid surface inside the tank called sloshing may occur. If high-amplitude sloshing occurs and the waves collide with the tank roof, it may lead to accidents such as damage to the tank roof or outflow of internal liquid. Therefore, it is important to predict the wave height of sloshing generated by an earthquake input. Sloshing is vibration of the free liquid surface, and when the sloshing wave height is small, it can be approximated with a linear vibration model. In that case, the velocity-response-spectrum method using velocity potential can estimate the sloshing wave height under an earthquake input. However, when the sloshing wave height increases and the sloshing becomes nonlinear, it is necessary to evaluate the wave height using other methods such as numerical analysis. Taking into consideration that design earthquake levels tend to increase and the use of seismic isolation mechanisms has continued to spread in recent years, the amplitude of the long-period components of an earthquake input which act on cylindrical tanks may also increase. Therefore, although the evaluation of nonlinear sloshing wave height is important, there are few examples which quantitatively evaluate the wave height of nonlinear sloshing. The purpose of this study is to construct a simple evaluation technique of a nonlinear sloshing wave height of cylindrical tanks. In this study, the shaking table test using the small cylindrical tank for studying the behavior of nonlinear sloshing was carried out. Furthermore, verification of the flow-analysis technique described by previous report (PVP2017-65313) was carried out by comparing with test results. As a result, the data for constructing an evaluation technique has been acquired. Moreover, the validity of the flow-analysis technique was has been verified.

When cylindrical tanks installed in the ground, such as oil tanks and liquid storage tanks, receive strong seismic waves, including the long-period component, motion of the free liquid surface inside the tank called sloshing may occur. If high-amplitude sloshing occurs and the waves collide with the tank roof, it may lead to accidents such as damage to the tank roof or outflow of internal liquid. Therefore, it is important to predict the wave height of sloshing generated by an earthquake input. Sloshing is vibration of the free liquid surface, and when the sloshing wave height is small, it can be approximated with a linear vibration model. In that case, the velocity-response-spectrum method using velocity potential can estimate the sloshing wave height under an earthquake input. However, when the sloshing wave height increases and the sloshing becomes nonlinear, it is necessary to evaluate the wave height using other methods such as numerical analysis. Taking into consideration that design earthquake levels tend to increase and the use of seismic isolation mechanisms has continued to spread in recent years, it is possible that the long-period components of an earthquake input which act on cylindrical tanks will also increase. Therefore, although it is thought that the evaluation of nonlinear sloshing wave height is important, there are few examples which quantitatively evaluate the wave height of nonlinear sloshing. In this study, as a simple evaluation technique of a nonlinear sloshing wave height, the applicability of the correction coefficient proposed by Shimada et al. was examined based on the flow analysis which used Volume of Fluid (VOF) method. Moreover, it was studied that the VOF method can be used to evaluate nonlinear sloshing wave height and sloshing wave crest impact pressure acting on the fixed roof of a tank. Shaking table tests will continue to be carried out in order to verify the applicability of the simple evaluation technique of nonlinear sloshing wave height. Results from flow analysis code will also be validated against these test results.

Experiments were performed with a 52.5 mm I.D., 90° elbow to study the internal two-phase flow induced fluctuating forces on pipe bends. The dynamic force signals were obtained directly from force sensors by separating the natural frequency of test section from the predominant frequency of excitation forces. A total of 36 tests were carried out to cover bubbly, slug, churn and annular flows. The results showed that for a fixed liquid flow rate, the predominant frequency of force peaked at slug flow regime. The root mean square value of force fluctuations continuously increased with gas flow rate and reached its maximum in annular flow regime. The excitation force presented a strong dependence on the momentum flux of two-phase flows. The integral of local pressure measurements could predict the time averaged momentum flux change reasonably well. However, the root mean square values of fluctuating forces were quite different due to the additional effect caused by the impact of liquid slugs on the elbow. The impact force, which has not been emphasized in the literature for the internal two-phase flow induced vibration analysis, is found to be significant in determining the force fluctuations in the slug flow regime. A two-phase flow induced excitation force model was developed based on the local instant formulation of two-fluid model. Analyses showed that the high frequency fluctuating components of centrifugal forces could be damped by the integral effect of the elbow.

The prevalence and incidence of food protein-induced enterocolitis syndrome (FPIES) are clearly not known; its onset before first feeding at birth especially has been rarely reported. A female newborn was referred to our institution due to blood-stained diarrhea before her first feeding at birth. Examination of the stool with Wright-Giemsa staining on day 6 revealed numerous fecal eosinophils, including Charcot-Leyden crystals. Lymphocyte stimulation test (LST) against cow's milk protein also showed positive values on day 12. The hematochezia resolved immediately after starting intravenous nutrition. She was fed with breast milk and extensively hydrolyzed formula and discharged from hospital on day 49. FPIES was diagnosed based on these symptoms and data. Our case was thought to have acquired allergic enterocolitis after sensitization in her fetal period, which caused severe FPIES triggered by the first intake of cow's milk soon after birth. The patient with FPIES presents atypical clinical findings, which is likely to cause misdiagnosis and delay of appropriate treatment. Heightened awareness and increased attention may be necessary to diagnose FPIES, even soon after birth. Evaluating fecal eosinophils and LST, which may be difficult to perform in every clinical hospital, is thought to be useful for the detection of FPIES without oral food challenge.

We have investigated the flow rate of methanol aqueous solutions through alginate sulfate (AS) electrolyte membranes under a constant pressure gradient. The solvent flow rate for the AS membranes with low cross-linking densities is considerably higher than that of alginic acid membrane when the methanol fraction (φ) is low. The solvent flow rate drastically decreases as φ increases, and no solvent permeation is observed when φ > 0.6. This strong φ dependence of flow rate is not simply explained by the φ dependence of swelling degree (Θ), because the reduction in Θ by increasing φ is considerably small. The confocal microscopy reveals a higher order network structure with a mesh size of ca. 10μm in the water-swollen AS membrane. The network structure results from the phase separation of the hydrophilic and hydrophobic domains. The hydrophilic and hydrophobic domains are mainly composed of the sulfated blocks and non-sulfated blocks, respectively. The mesh size of the network structure becomes considerably smaller as φ increases. The solvent permeability of the AS membranes is mainly controlled by the mesh size of the higher order network structure.

The damp-heat test and the combined acceleration test composed of UV irradiation and subsequent damp-heat stress were conducted on multicrystalline silicon photovoltaic modules by changing the gas barrier property of a backsheet. In the damp-heat test, the deterioration greatly differed depending on the difference in the barrier property of the backsheet, whereas in the combined acceleration test, the degradation was less susceptible to the effect of such a difference. The difference in the manner of spreading deterioration between both tests was observed in electroluminescence images. From these results, it is considered that the degradation mechanism in the case of the combined acceleration test is different from that in the case of the damp-heat test.

As for thin walled cylindrical liquid storage tanks in nuclear power plants, the current elastic design guideline against seismic loading might result in too conservative component design. Therefore, it is thought possible to make the design procedure more reasonable by taking dynamic response reduction into account. Experiments using scaled models as well as numerical analyses were carried out, and seismic behavior of thin walled cylindrical liquid storage tanks was simulated to investigate energy absorption capacity and seismic resistance of those tanks. Based on the test and analysis results, assessment procedure for buckling considering post-buckling behavior has been proposed.

When a thin walled cylindrical liquid storage tank is exposed to a very large seismic base excitation, buckling phenomena such as elephant foot bulge at the bottom portion and nonlinear ovaling vibration at the upper portion may be caused. In the 1st report, elephant foot bulge phenomena and the liquid pressure effect were investigated. In this report, nonlinear ovaling vibration phenomena were investigated based on the dynamic buckling tests and the external pressure buckling analysis by FEM, using scale models of thin cylindrical liquid storage tanks for the nuclear power plants. The mechanism and the effects of vertical excitation and liquid sloshing were studied and discussed. As a result, it was found that the negative pressure will dominate the occurrence of the nonlinear ovaling vibration and the effects of sloshing and vertical excitation are relatively small. Moreover it was thought that the nonlinear ovaling vibration observed here is buckling phenomeon due to the external liquid pressure.

When a thin walled cylindrical liquid storage tank is exposed to a very large seismic base excitation, buckling phenomena may be caused such as bending buckling where diamond buckling pattern or elephant foot bulge pattern will be found at the bottom portion, and shear buckling at the middle portion of the tank. In this study, dynamic buckling tests were performed using scale models of thin cylindrical liquid storage tanks for the nuclear power plants. The input seismic acceleration was increased until the elephant foot bulge occurred and the vibrational behavior before and after buckling was investigated. And the effects of static and dynamic liquid pressure on the bending buckling patterns and the buckling critical force was investigated by fundamental tests using small tank models.

In this study, fluctuating force induced by both upward and horizontal gas-liquid two-phase flow on 90 degree pipe bend at atmospheric condition was investigated. First, the database comprised of dynamic force signals and two-phase flow parameters such as volumetric fluxes, area averaged void fraction and pressure fluctuations covering entire two-phase flow regimes was developed for both flow orientations. Then, study was conducted to develop a model which is capable of predicting the force fluctuation frequency and magnitudes particularly for the slug flow regime. The model was fundamentally developed from the local instantaneous two-fluid model which was applied to the control volume around the elbow test section. Main contribution of the force fluctuation of two-phase flow is from the momentum and pressure fluctuations for most of the flow regimes. For slug flow regime, however, water-hammer like impact was produced by the collision of liquid slug against the structure surface. In order to consider that effect, the liquid slug impact force model was developed. The model utilizes two-group interfacial area concentration correlation to treat the flow regime transition without an abrupt discontinuity. It was found that the newly developed model is capable of predicting two-phase flow induced force fluctuation and dominant frequency range with satisfactory accuracy for flow regimes up to churn-turbulent.Copyright © 2014 by ASME

This paper proposes a tactile display for presenting shear deformation to the skin of the human finger. Human can get much information from the sense of tactile. Using this information, human can perform dexterous manipulation. It is thought that this information is based on the skin deformation, so we aim to present the skin deformation. For the tactile display that can present skin deformation, we fabricated the three dimensional moving stage that is driven by the hydraulic pressure. We performed experiments to present shear deformation using this display system. From this experiment, it is clear that the deformation speed influences on the perception of the skin deformation. For presenting different deformation under the condition of same normal pressure, we use an air pad that can vacuum air. Using this air pad and the hydraulic display system, we performed experiments to present shear deformation using air vacuum. From this experiment, we. can present large deformation under the condition of same normal pressure.

XPS spectra associated with surface core-level shifts (SCLS) for the InSb{111}A, B-(2×2) surfaces are fitted with the curves represented by the Voigt function. While testing as to how the Voigt function changes with detection angle, the Lorentzian width included in the function remains almost unchanged, whereas the Gaussian width becomes broadened with an increase in detection angle. This Voigt function allows to decompose a spectrum of interest into bulk and SCLS component with sufficient intensity, realizing quantitative estimation for the SCLS intensity.

This paper proposes Tactile Display for presenting the moving or shearing direction to the skin of human finger. In many type sense which human finger has, by using vibro-tactile stimulation we aim at the development of tactile feedback system. The vibro-tactile stimulator utilizes vibrating pins to provide ticking sensation to the human operator's skin. We use the micro resonator which is driven by electro-magnetic force for vibrating pin. We make an experiment which present vibro-tactile stimulation using micro resonator and confirm the ability to perceive the vibro-tactile stimulation. Next we array the micro resonator as matrix state and construct the tactile display. We show the tactile feedback experiment using this display in this paper. At the experimental results, it becomes cleared that the tactile display has the ability to present much information to the skin of human being.

Fluidelastic instability (FEI) remains the most important vibration mechanism in steam generators. Fluidelastic instability of an array of tubes thought to be mainly occurred in the cross-flow direction. In the present day, some researchers reported possibility of occurrence of fluidelastic instability in the in-flow direction. However, the phenomenon of the in-plane FEI has not been well recognized compared to the transverse FEI. In this study, air flow tests using cantilevered straight cylinder array of tubes in triangular configuration were conducted. It is confirmed that the in-flow FEI could be occurred and the critical flow velocity in the in-flow direction is larger than that of in the cross flow direction. Furthermore, the relationship between P/D of an array of tubes and the critical flow velocity in the in-flow direction was also investigated.

For high earthquake resistance and ease of installation, free standing racks which are not anchored to the pool floor or walls has been adopted in many countries. Under the earthquake, the response of the free standing rack is highly nonlinear and involves a complex combination of motions (sliding, rocking, twisting, and turning) and impacts between the fuel assemblies and the fuel cell walls, rack-to-rack, and the pit floor and the rack pedestals. To obtain an accurate simulation of the free standing rack, the seismic analysis requires careful considerations of these complex phenomena (sliding, rocking, twisting, and turning), fluid coupling effects and frictional effects. The important evaluation items while applying the free standing rack to the actual nuclear plants are maximum sliding displacement of the rack, maximum rocking displacement and maximum leg load under earthquake. When the sliding displacement increases, the rack may collide against the spent fuel pool wall. In addition, the free standing rack should not exhibit tilt sufficient to cause to the rack to overturn. The vibration tests were conducted in order to predict the rack behavior under earthquake, and the analysis method was validated by comparison to tests results. Furthermore, we developed the seismic design method to obtain the margin of safety for free standing rack.

Background BioHackathon 2010 was the third in a series of meetings hosted by the Database Center for Life Sciences (DBCLS) in Tokyo, Japan. The overall goal of the BioHackathon series is to improve the quality and accessibility of life science research data on the Web by bringing together representatives from public databases, analytical tool providers, and cyber-infrastructure researchers to jointly tackle important challenges in the area of in silico biological research. Results The theme of BioHackathon 2010 was the 'Semantic Web', and all attendees gathered with the shared goal of producing Semantic Web data from their respective resources, and/or consuming or interacting those data using their tools and interfaces. We discussed on topics including guidelines for designing semantic data and interoperability of resources. We consequently developed tools and clients for analysis and visualization. Conclusion We provide a meeting report from BioHackathon 2010, in which we describe the discussions, decisions, and breakthroughs made as we moved towards compliance with Semantic Web technologies - from source provider, through middleware, to the end-consumer.

The spent fuel rack of a nuclear plant stores the spent fuel temporarily before it can be moved to a reprocessing facility. Therefore, the spent fuel rack must have a high tolerance against big seismic loads. Sliding and rocking motions of full-scale rack model having full loading fuel assembly subjected to the seismic excitation are studied [1]. We carried out the seismic test of the free standing rack under some conditions. The distribution of the fuel assembly affects the sliding and rocking motions of the rack, and the outer plate reduces the rack response level by fluid effect. We made sure of them by seismic experiment using a shaking table. In this paper, sliding and rocking motions of full-scale rack model under some conditions are studied. To develop an analysis evaluation method of the rack sliding and rocking motions, we obtained the fundamental data about the free standing rack by seismic test using a shaking table.