High frame-rate tracking of multiple color-patterned objects

In this study, we develop a high frame-rate vision system that can execute color histogram-based tracking of multiple color-patterned objects in a 512 × 512 image at 2,000 fps by implementing an expanded cell-based labeling algorithm as the hardware logic. In the hardware implementation of the expanded cell-based labeling algorithm, the 16-bin hue-based color histograms of 1,024 color-patterned objects in an image can be extracted simultaneously by dividing the image into 8 × 8 cells concurrently, after calculating the 0th, 1st, and 2nd moment features to obtain the positions, areas, and orientation angles of multiple objects. We verified the effectiveness of our developed tracking system by performing several experiments using multiple color-patterned objects, which were always tracked even when they moved rapidly with occlusions in the camera views.     

Cyclic motion design and analysis for a passive object manipulation using an active plate

We propose a novel scheme for manipulating a passive object using an active plate. In previous studies, cyclic manipulations that transport objects on a plate, position control of an object on a plate, and juggling have been realized. In most manipulations using plates, object motions in the direction of the gravitational force are not considered. The objective of this study is to control an object’s orientation with respect to the gravitational force direction using an active plate for realizing hitherto unrealized object motion. In this context, a tumble doll, which is a planar rigid sphere, is defined as the object. Motions of the object and active plate are designed to be cyclic. A state vector composed of the object’s angle and angular velocity is defined, and the cyclic motion is expressed as a nonlinear discrete system. Fixed points of the state vector are searched for in the designed cyclic motion. A stability analysis around the fixed points is conducted using a Poincaré map. As a result, the fixed points are shown to be asymptotically stable. Finally, experimental results are used to verify that the object’s angle can be manipulated with the designed cyclic motion using the plate.     

Photografting of N‐isopropylacrylamide and glycidyl methacrylate binary monomers on polyethylene film: Effect of mixed solvent consisting of water and organic solvent

Photografting (λ > 300 nm) of N‐isopropylacrylamide (NIPAAm) and glycidyl methacrylate (GMA) binary monomers (NIPAAm/GMA) on low‐density polyethylene film (thickness = 30 μm) was investigated at 60°C using mixed solvent consisting of water and an organic solvent such as acetone. Xanthone was used as a photoinitiator by coating it on the film surfaces. A maximum percentage of grafting was observed at a certain concentration of acetone in the mixed solvent, which was commonly observed for both ratios of NIPAAm/GMA, 8/2 and 7/3. Based on the photografting of NIPAAm/GMA on xanthone‐coated film, monomer reactivity ratios of NIPAAm (r₁) and GMA (r₂) were calculated using the Fineman–Ross method. The values were 0.31 ± 0.1 and 4.8 ± 0.2 for the water solvent system, while they were 0.96 ± 0.1 and 4.9 ± 0.1 for the mixed solvent system. NIPAAm/GMA‐grafted films with a homogeneous distribution of grafted chains were formed by photografting using water and mixed solvents. The NIPAAm/GMA‐grafted films exhibited temperature‐responsive characters, whereas the grafted films showed a reversible change in the degree of swelling between 0 and 50°C, respectively. Epoxy groups in the grafted poly(NIPAAm/GMA) chains could be aminated with ethylenediamine in N,N′‐dimethylformamide at 70°C for 3 h. Complexes of the aminated NIPAAm/GMA‐grafted chains with cupric ion exhibited catalytic activity for the decomposition of hydrogen peroxide at 20 to 50°C. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2469–2475, 2005     

cis-Vaccenic acid in mango pulp lipids

A peak corresponding to a methyl octadecenoate other than oleate has been detected on the capillary gas chromatogram of the methyl esters of mango pulp fatty acids. This octadecenoate was isolated by silica gel and argentation column chromatography, high performance liquid chromatography and argentation thin layer chromatography, and then analyzed by infrared, nuclear magnetic resonance and gas chromatography-mass spectrometry, chromatographic separations and oxidative degradation. These analytical data proved that the octadecenoic acid wascis-vaccenic acid (cis-11-octadecenoic acid). The concentration of this acid in total octadecenoic acids ranged from 35% to 50% in the pulp of mangoes from Fiji, Mexico, the Philippines and Taiwan.cis-Vaccenic acid was revealed to be one of the major component fatty acids of non-polar lipids (mainly triacylglycerols), glycolipids and phospholipids in mango pulp. The glycolipids containedcis-vaccenic acid (ca. 20%) in higher concentration than oleic acid (ca. 15%). A trace amount ofcis-vaccenic acid (0.5%) was detected in the total lipids of mango seeds. Profile of fatty acid composition of mango pulp lipids (0.2–0.3 wt% of wet pulp) was characterized by the presence of n−7 acid isomers,cis-vaccenic acid and palmitoleic acid, and unusual mono- and dienoic positional isomers.     

Shape optimization of continua using NURBS as basis functions

The present paper introduces a numerical solution to shape optimization problems of domains in which boundary value problems of partial differential equations are defined. In the present paper, the finite element method using NURBS as basis functions in the Galerkin method is applied to solve the boundary value problems and to solve a reshaping problem generated by the H1 gradient method for shape optimization, which has been developed as a general solution to shape optimization problems. Numerical examples of linear elastic continua illustrate that this solution works as well as using the conventional finite element method.     

Decentralized load frequency based on H∞ control

This paper presents a decentralized load frequency control (LFC) based on H_∞ optimal control theory with an observer. A few LFC schemes have been proposed based on the optimal control theory, but they have not considered the change of system parameters in operation and the characteristics of load disturbances in a target system. In this paper, H_∞ robust control is introduced to address such problems. Owing to its practical merit, the proposed control scheme is a decentralized LFC. Employing observer theory, the proposed method requires only frequency and tie‐line power deviation in each area. Numerical simulations are shown to demonstrate the effectiveness of the proposed method. H_∞ control was proven to show greater effectiveness of damping disturbance over the conventional optimal control by the design of control systems aimed at restricting the H_∞ norm of its transfer function. In particular, when a decentralized LFC is applied, by reducing the system size, H_∞ norm is easier to dampen; thus H_∞ control is more effective in the decentralized control. Future research topics include the design of H_∞ control system with a weight on frequency response. © 2001 Scripta Technica, Electr Eng Jpn, 136(3): 28–38, 2001     

Fluxless fabrications of Sn-Au solder microbumps by a hydrogen plasma reflow technique

Solder microbumps of 0.95Sn-0.05Au were successfully fabricated on a compound semiconductor wafer by reflowing a multilayer metal film in hydrogen plasma atmosphere. The microbumps melt at as low a temperature as 220°C, which is close to the lowest eutectic temperature (217°C) in a Sn-Au system. Fluxless reflowing was achieved by using hydrogen radicals. The low-temperature fluxless fabrication of Sn-Au solder microbumps is a very useful technique for electrical connection between a compound semiconductor chip and a substrate.     

Investigation of meshing phenomenon of hypoid gears with different offsets via high response infrared video thermography

Forschung im Ingenieurwesen - Hypoid gears are widely used in automobile differentials. Furthermore, it is well known that the efficiency of hypoid gears is lower than that of other gears due to...     

Characterization of Transformation Stasis in Low-Carbon Steels Microalloyed with B and Mo

In the present study, bainite transformation kinetics was examined in low C-Mn steels with the addition of small amounts of B and Mo. This addition delays the onset of the bainite transformation. Mo addition causes transformation stasis at temperatures between 873 K and 823 K (600 °C and 550 °C) just below the bainite-start (B _s) temperature, resulting from an incomplete bainite transformation. Post-stasis transformation after a prolonged hold proceeds by the formation of ferrite with a low dislocation density, and in Mo-containing alloys, often the formation of carbides. The volume fraction at which the transformation stops is higher for lower carbon contents and lower transformation temperatures. By contrast, at 773 K (500 °C), the bainite transformation accompanying cementite precipitation occurs regardless of microalloying and is completed after shorter hold times. EDX measurement performed on the Mo-added 0.15 pct C alloy with aberration-corrected STEM revealed that segregation at the bainite/austenite interphase boundary is small for Mn and negligible for Mo in the early stages of stasis, which does not support the incomplete transformation mechanism based on the solute drag theory for the alloys used.     

在高浓度尿素的存在下采用制备型电泳体系进行聚丙烯酰胺凝胶电泳分离腐植酸成分

采用制备型电泳体系在高浓度的尿素存在下进行聚丙烯酰胺凝胶电泳分离水溶性腐植酸中的不同成分。在聚丙烯酰胺凝胶电泳中,根据水溶性腐植酸中深色成分分子大小的不同能够将它们彼此分离开来,同时还可以通过酸沉淀的方法将这些深色物质重新回收。水溶性腐植酸中大部分的荧光物质分子尺寸都很小,这使得它们可以溶于酸,并且被酸溶解的荧光物质可以通过吸附在DAX-8树脂上而重新获得。但是,水溶性腐植酸中的非荧光物质则会在电泳过程中丢失。而那些被认为是小分子的荧光物质则会通过氢键的断裂和7 M尿素的疏水作用得到分离。漫反射傅里叶变换红外光谱的测量结果表明腐植酸中不同成分的化学性质是不同的。而实验结果表明在高浓度尿素存在下聚丙烯酰胺凝胶电泳是分离和收集水溶性腐植酸中各组分的一种很有用的方法。