A graphical solution of multimodal optimization to improve food properties

Abstract

When the search spaces were set excessively broad, the random‐centroid optimization (RCO) was difficult to home‐in on the global optimum in the case of multimodal functions. A preliminary narrowing strategy was introduced based on the general trend of steeper slopes toward the global optimum than those toward local optima. The search spaces were narrowed to half for factors at either end by comparing response values at both extreme terminals (0.1 and 0.9 in the full space of 0‐1.0) of the search space (half‐space design). The differences (or ratios) of these two values represented the slopes. This new method was more reliable than repeating probabilistic random search to narrow search spaces prior to RCO as reported in the previous paper (Nakai et al., 1998a). However, for most of the ordinary optimization projects with reasonable sizes of the search spaces, there was no need of using this half‐space design search. Application of the RCO, by changing the amount of FeCl2 to add to fish actomyosin at a low concentration and heating temperature and time, efficiently maximized the breaking strength of the gels formed.     

Photoinduced Synthesis of P‐Perfluoroalkylated Phosphines from Triarylphosphines and Their Application in the Copper‐Free Cross‐Coupling of Acid Chlorides and Terminal Alkynes

A practical synthesis yielding P‐perfluoroalkylated phosphines from triarylphosphines and perfluoroalkyl iodides has been developed. The photoinduced reaction involves the substitution of aryl groups on the phosphorus atom with perfluoroalkyl groups to successfully afford P‐perfluoroalkylated phosphines. In addition, the P‐perfluoroalkylated phosphines were found to promote the Cu‐free cross‐coupling reaction of acid chlorides with terminal alkynes.

     

Resistance spot welding of metal/carbon-fibre-reinforced plastics and applying silane coupling treatment

Dissimilar materials joining of SUS304 and carbon-fibre-reinforced plastics consisting of short fibres and thermoplastics was performed. The materials were joined by series resistance spot welding. The electrodes were pressed on the metal plate of the lap joint of metal/carbon-fibre-reinforced plastics. The SUS304 plate was heated by resistance heating, causing the thermoplastic near the interface to melt slightly because of heat conduction. SUS304 could be joined directly to carbon-fibre-reinforced polyamide and modified polypropylene, but not to polyphenylene sulphide. The joining area increased with an increase in the welding current and welding time, so did the tensile shear fracture load. Furthermore, the silane coupling agent treatment of SUS304 was highly effective in increasing the joining strength.     

Effect of Fe and partial pressure of oxygen on the formation and phase transformation behavior of Al2O3 scale

The effect of oxygen partial pressure on the phase transformation of Al₂O₃ scale on various Fe–Al alloys with and without very thin (～100 nm) Fe coating was investigated. Fe‐coating on Fe–Al alloys can effectively suppress metastable Al₂O₃ formation, but little effect was observed when the samples were oxidized in a low partial pressure of oxygen. Under the low ${\rm P}_{{\rm O}_{{\rm 2}} } $ atmosphere, metastable to stable α‐Al₂O₃ scale phase transformation on both Fe‐coated and non‐coated Fe–Al alloys was significantly delayed. The lattice spacing of α‐Al₂O₃ scale formed in air decreased with increasing alloy Al content. Further decrease in the lattice spacing of α‐Al₂O₃ scale was observed when the alloy was oxidized in low ${\rm P}_{{\rm O}_{{\rm 2}} } $ . The results obtained clearly indicated that the formation of Fe₂O₃ or Fe³⁺ in metastable Al₂O₃ accelerated the metastable to stable α‐Al₂O₃ scale transformation.     

A New Adaptive Method For Identification Of Critical Gain Using Saturation Function

A new adaptive method for identification of the critical gain is proposed. Instead of using relay feedback, a saturation nonlinearity and an adjusting gain are inserted in the loop, and the gain is tuned by the difference signal between the input and the output of the saturation function. The gain decreases monotonically and converges to a constant, which can be very close to the critical gain. It is shown that the feedback system does not become unstable by this method. This method can be easily extended to the multi‐input multi‐output plants.     

Synthesis and Properties of Neptunium(V) Propionates

From propionate-containing solutions of Np(V), the crystalline compounds NpO₂OOCC₂H₅·nH₂O with n = 1 or 2 and M(NpO₂)₂(OOCC₂H₅)₃·H₂O with M = NH₄ or Cs were separated. Their X-ray powder patterns were recorded and behavior at heating was studied. The IR and electronic absorption spectra suggest that, in these compounds, the NpO₂ ⁺ ions are coordinated with each other to form cation-cation bonds involving all yl oxygen atoms.     

Thermoresponsive Emission Switching via Lower Critical Solution Temperature Behavior of Organic–Inorganic Perovskite Nanoparticles

Lead halide perovskites have shown much promise for high‐performing solar cells due to their inherent electronic nature, and though the color of bright‐light emitters based on perovskite nanoparticles can be tuned by halide mixing and/or size control, dynamic switching using external stimuli remains a challenge. This article reports an unprecedented lower critical solution temperature (LCST) for toluene solutions containing methylammonium lead bromide (MAPbBr₃), oleic acid, alkylamines, and dimethylformamide. The delicate interplay of these molecules and ions allows for the reversible formation and decomposition of MAPbBr₃ nanoparticles upon heating and cooling, which is accompanied by green and blue photoemissions at each state. An intermediate 1D crystal with PbBr₂‐amine coordination is found to play pivotal role in this, and a mechanistic insight is provided based on a three‐state model. In addition to a high quantum yield (up to 85%), this system allows for control over the cloud point (30?80 °C) through compositional engineering and the luminescent color (blue to red) via halogen exchange, thus making it a versatile solution for developing functional molecular organic–inorganic LCST quantum dots.     

Three-dimensional deformation analyses of the ultra-thin liquid film surface (linearized analyses for the steady state)

Long wave theory, which is the time evolution equation for the shape and deformation of thin liquid films and includes surface tension and surface forces such as van der Waals forces, was used to examine steady and three-dimensional deformations of ultra-thin but continuous liquid films. As liquid film deformations caused by gas pressures and shear stresses at the gas–liquid interface are usually very small, the linearized long wave equation, which is obtained for infinitesimal deformations, was employed to predict the steady-state liquid surface deformations produced by gas pressures and shear stresses. As the velocity of the solid increases and the liquid film thickness decreases, the deformation decreases and is nearly constant along solid running direction almost everywhere except at the applied position of the pressure and shearing stresses. The results obtained using the linearized equation agrees well with those obtained using the nonlinear equation and the calculation time is greatly reduced.     

Low‐order H∞ controller design on the frequency domain by partial optimization

In this paper, an optimization method of low‐order multivariable controllers for H_∞ control is proposed. Starting from a low‐order stabilizing controller, our method gives a sequence of controllers for which the H_∞ norm performance index is monotonically non‐increasing by tuning the numerator coefficient matrices of the low‐order controller. This controller class includes multivariable PID controllers. The proposed method is a descent method where the feasible direction is calculated by solving a linear matrix inequality that represents a sufficient condition for the H_∞ criterion for each frequency. Usefulness is shown by two numerical examples. Copyright © 2009 John Wiley & Sons, Ltd.     

A new wettability‐control technique for fabricating color OLED panels by an ink‐jet‐printing method

Abstract— The fabrication technique for color OLED panels by means of wettability‐controllable hole‐injection material (HIM) and a photocatalytic lithography method achieves both precise ink‐jet printing and long‐lifetime devices. The technique enables us to selectively change the non‐wetting surface of a hole‐injection layer (HIL) of metal‐oxide nanoparticles (MONPs) into a wetting surface without damage to the device performance. Wetting patterns formed by this method with photocatalyst‐coated photomasks made it possible to print emission material with patterns of precisely 98‐μm widths on the hole‐injection layer. A fluorescent green‐emitting device fabricated with an HIM of MONPs by the photocatalytic treatment exhibited a long lifetime of 365 hours at30,000 cd/m², which can be extrapolated to a lifetime of more than 110,000 hours at 1000 cd/m², assuming an acceleration coefficient of 1.7. A two‐color device and a monochrome passive‐matrix panel were also successfully fabricated. The two‐color device emitted light without the mixing of colors. The monochrome panel displayed alphabetical characters with good uniformity and no flaws.