Experimental study of cell pattern formation induced by internal heat sources in a horizontal fluid layer

This study determines the flow structure in a convection cell with an internally heated layer by PIV to elucidate the convection cell transition mechanisms. The vertical velocity component is determined and the cell behaviour with respect to Rayleigh number is investigated quantitatively. Cell expansion process is described as a consequence of development of the descending flow at the centre of cells. The results suggest that a spoke-like structure is stable in this system in ideal conditions and a double-cell structure is formed when there are restrictions on the system, i.e. finite lateral boundaries.     

Conjoint analysis on the purchase intent for traditional fermented soy product (natto) among Japanese housewives

Abstract: The effect of sensory and extrinsic attributes on consumer intentions to purchase the Japanese traditional fermented soybean product natto was evaluated using conjoint analysis. Six attributes with 2 levels each were chosen and manipulated: price (high compared with low), the country of origin of the soybeans (domestic compared with imported), stickiness (strong compared with moderate), smell (rich compared with moderate), attached seasonings (attached compared with no attached seasonings), and the environmental friendliness of the packaging (high compared with low). A fractional factorial design was applied and 8 hypothetical product labels were produced. A sample of 479 Japanese housewives ranked these product labels based on their purchase intentions. Overall purchase intention was affected by country of origin, attached seasonings, and price; those attributes accounted for 81.0%, while the sensory attributes of the product accounted for 19.0% of purchase intents. In order to estimate market segments for the natto products based on consumer preference, a cluster analysis was performed. It identified 4 segments of consumers: 1 oriented to attached seasonings, another conscious of the price, and the other 2 oriented to origins. The behavioral and demographic characteristics of the respondents had a limited influence on segment membership. Practical Application: This research was conducted to understand how consumers valuate various sensory and nonsensory product attributes based on their assessment of the overall product in the case of Japanese fermented soy product (natto). The data of this research would be of great importance both in understanding consumer behavior and in designing strategies for product development.     

SCCN: A Time-Effective Hierarchical Interconnection Network for Network-On-Chip

Mobile Networks and Applications - The needed time to send and receive a message among two nodes in an interconnection network has a fundamental role in determining the performance of this network....     

A Fluid Liquid‐Crystal Material with Highly Polar Order

An anomalously large dielectric permittivity of ≈10⁴ is found in the mesophase temperature range (MP phase) wherein high fluidity is observed for a liquid‐crystal compound having a 1,3‐dioxane unit in the mesogenic core (DIO). In this temperature range, no sharp X‐ray diffraction peak is observed at both small and wide Bragg angles, similar to that for a nematic phase; however, an inhomogeneous sandy texture or broken Schlieren one is observed via polarizing optical microscopy, unlike that for a conventional nematic phase. DIO exhibits polarization switching with a large polarization value, i.e., P = 4.4 µC cm^?2, and a parallelogram‐shaped polarization–electric field hysteresis loop in the MP phase. The inhomogeneously aligned DIO in the absence of an electric field adopts a uniform orientation along an applied electric field when field‐induced polarization switching occurs. Furthermore, sufficiently larger second‐harmonic generation is observed for DIO in the MP phase. Second‐harmonic‐generation interferometry clearly shows that the sense of polarization is inverted when the +/? sign of the applied electric field in MP is reversed. These results suggest that a unidirectional, ferroelectric‐like parallel polar arrangement of the molecules is generated along the director in the MP phase.     

Numerical simulation of particulate cake formation in cross-flow microfiltration: Effects of attractive forces

We present a two-dimensional simulation model to explore cake formation in cross-flow filtration. The model uses the lattice Boltzmann method (LBM) for fluid computation and the discrete element method (DEM) for particle computation; they were fully coupled with the smoothed profile method. We verified our model by simulating filtration under different transmembrane pressures. We then investigated the effects of attractive forces and particle concentration on the cake formation mechanism. Generally, as the attractive interaction and particle concentration increased, the particles formed a cake layer with a looser body and rough surface, due to the decrease in the mobility of the particles in contact with the cake surface. It is concluded that the effects of particle concentration are affected by the different conditions of attractive interactions between the particles.     

An estimation of friction from the indentation of metals by acute-angled conical indenters

The paper describes a method for estimating the coefficient of friction (COF) between sliding surfaces by an indentation of an acute-angled indenter. The COF estimated by the method is compared with the COF measured by a friction tester. The conical indenter, which is made of WC and has an apex angle of 45°, is used for the experiments. A micro-Vickers hardness tester is used for the indentation tests. The friction tester used is one of Bowden–Leben type. A copper and a 0.45% carbon steel are used for the indentation and sliding specimens. The estimation of the COF is based on the equilibrium equation of indentation, which takes the friction between the contacting surfaces of the indenter and the specimen into consideration. The results show that the estimated COF is approximately equal to the measured one. Based on the results, the validity of this method is discussed.     

Dirac Cone Spin Polarization of Graphene by Magnetic Insulator Proximity Effect Probed with Outermost Surface Spin Spectroscopy

The effects of the proximity contact with magnetic insulator on the spin‐dependent electronic structure of graphene are explored for the heterostructure of single‐layer graphene (SLG) and yttrium iron garnet Y₃Fe₅O₁₂ (YIG) by means of outermost surface spin spectroscopy using a spin‐polarized metastable He atom beam. In the SLG/YIG heterostructure, the Dirac cone electrons of graphene are found to be negatively spin polarized in parallel to the minority spins of YIG with a large polarization degree, without giving rise to significant changes in the π band structure. Theoretical calculations reveal the electrostatic interfacial interactions providing a strong physical adhesion and the indirect exchange interaction causing the spin polarization of SLG at the interface with YIG. The Hall device of the SLG/YIG heterostructure exhibits a nonlinear Hall resistance attributable to the anomalous Hall effect, implying the extrinsic spin–orbit interactions as another manifestation of the proximity effect.     

Hazard curve evaluation method development for a forest fire as an external hazard on nuclear power plants

A method to obtain a hazard curve of a forest fire was developed. The method has four steps: a logic tree formulation, a response surface evaluation, a Monte Carlo simulation, and an annual exceedance frequency calculation. The logic tree consists domains of “forest fire breakout and spread conditions”, “weather conditions”, “vegetation conditions”, and “forest fire simulation conditions.” Condition parameters of the logic boxes are static if stable during a forest fire or not sensitive to a forest fire intensity, and non-static parameters are variables whose frequency/probability is given based on existing databases or evaluations. Response surfaces of a reaction intensity and a fireline intensity were prepared by interpolating outputs from a number of forest fire propagation simulations by fire area simulator (FARSITE). The Monte Carlo simulation was performed where one sample represented a set of variable parameters of the logic boxes and a corresponding intensity was evaluated from the response surface. The hazard curve, i.e. an annual exceedance frequency of the intensity, was therefore calculated from the histogram of the Monte Carlo simulation outputs. The new method was applied to evaluate hazard curves of a reaction intensity and a fireline intensity for a typical location around a sodium-cooled fast reactor in Japan.