Proposal for st-Routing Protocol

A routing protocol chooses one of the several paths (routes) from a source node to a destination node in the computer network, to send a packet of information. In this paper, we propose a new routing protocol, which we call st-routing protocol, based on st-numbering of a graph. The protocol fits well in noisy environments where robustness of routing using alternative paths is a major issue. The proposed routing protocol provides a systematic way to retry alternative paths without generating any duplicate packets. The protocol works for only those networks that can be represented by biconnected graphs.     

A Method of Football-Offside Detection Using Multiple Cameras for an Automatic Linesman Assistance System

In offside detection during a football match, afterimage and occlusion confuse the linesman and the referee, and this confusion can cause judgment errors. This paper proposes a method of football-offside detection using multiple cameras in an automatic linesman assistance system. In this method, multiple cameras and offside detection units are installed as a hardware system, and offside will be alerted when at least one of the offside detection units detects offside. In an offside detection unit, when the offside position is determined, offside is immediately judged in the case in which the ball is passed from an attacker to another attacker who is located nearer the opponent-goal line than the most-back defender and the ball. The vertical lines that represent these attackers, defenders and ball are used as their positions for logically judging the offside. Experiments were performed using video clips from 381 tournaments of English Premier Leagues from 2016 to 2017. The results showed 98.50% accuracy compared with the expert.

     

Reaction behaviour of Ni1?x M x O’s (M?=?Li, Na) formation and its thermoelectric properties

Reaction behaviour of the mixed reactant powder of NiO and M₂CO₃ (M = Li, Na) for the formation of Ni_1−x M _x O (M = Li, Na) was investigated. Ni_1−x M _x O (M = Li, Na) compacts were fabricated by sintering green compacts of the mixed reactant powder at 1,173 K for 5 h in air. The results indicated that Ni_1−x M _x O (M = Li, Na) was successfully synthesized when the sintering temperature was approximately above 800 K. In addition, the resultant Ni_1−x M _x O (M = Li, Na) kept the same crystal structure with that of NiO (except for x = 0.4), but the diffraction peaks were found to shift to larger diffraction degrees compared with that of NiO. Interestingly, Li ions distribute in the lattice of NiO uniformly. Meanwhile, the electrical resistivity of the sintered compacts decreased and their semiconductor behaviour was always maintained with the increase of doping Li or Na. The power factor was increased significantly and exceeded 1.8 × 10⁻⁴ Wm⁻¹ K⁻² at 823 K.     

Carbides in high-speed steels containing silicon

The effects of silicon additions up to 3.5 wt pct on the as-cast carbides, as-quenched carbides, and as-tempered carbides of high-speed steels W3Mo2Cr4V, W6Mo5Cr4V2, and W9Mo3Cr4V were investigated. In order to further understand these effects, a Fe-16Mo-0.9C alloy was also studied. The results show that a critical content of silicon exists for the effects of silicon on the types and amount of eutectic carbides in the high-speed steels, which is about 3, 2, and 1 wt pct for W3Mo2Cr4V, W6Mo5Cr4V2, and W9Mo3Cr4V, respectively. When the silicon content exceeds the critical value, the M₂C eutectic carbide almost disappears in the tested high-speed steels. Silicon additions were found to raise the precipitate temperature of primary MC carbide in the melt of high-speed steels that contained d-ferrite, and hence increased the size of primary MC carbide. The precipitate temperature of primary MC carbide in the high-speed steels without d-ferrite, however, was almost not affected by the addition of silicon. It is found that silicon additions increase the amount of undis-solved M₆C carbide very obviously. The higher the tungsten content in the high-speed steels, the more apparent is the effect of silicon additions on the undissolved M₆C carbides. The amount of MC and M₂C temper precipitates is decreased in the W6Mo5Cr4V and W9Mo3Cr4V steels by the addition of silicon, but in the W3Mo2Cr4V steel, it rises to about 2.3 wt pct.     

Intra-aortic balloon pump driven by a linear pulse motor

The Intra-Aortic Balloon Pump (IABP) is an effective device in assisting circulation. However, a small-sized IABP is required in related fields. This paper proposes a new small-sized IABP which is driven by a Linear Pulse Motor (LPM) rather than an air-driven motor. In general, the LPM has advantages of high thrust/input power and good controllability. The developed LPM for the IABP drive has high thrust/input power of 19.9 newtons/W. It also has kinetic thrust of 270 newtons at the range of speed from 100 to 140 mm/s. The IABP using the LPM has an extremely simple construction. As the result of mock testing, the IABP using an LPM not only gives the same performance as the ordinary air-driven IABP, but the mass of the IABP will be reduced to half the size of the ordinary one.     

An algebraic approach to H∞ output feedback control problems

We derive an output feedback controller which stabilizes a system and satisfies a prescribed H_∞ norm bound of the closed loop transfer function. The proposed design method is available for any system, i.e. there are no restrictions on D₁₂ and D₂₁. This approach utilizes only algebraic operations, thus proofs are simple and clear.     

Degree of comonomer inclusion into lamella crystal for propylene/olefin copolymers

Copolymers of propylene with ethylene, butene-1, hexene-1, and octene-1 were synthesized with isospecific metallocene catalyst system. Crystalline structure of the melt-crystallized samples was investigated from the viewpoint of the comonomer location in a solid-state of the copolymers, using the fuming nitric acid (FNA) etching technique followed by ¹³C NMR spectrum measurement. It was found that the copolymers were oxidatively degraded with FNA at 50 °C and the residue after etching was corresponding to the lamella crystal of the original state. ¹³C NMR spectrum of the residue revealed that all kinds of comonomer used here were located not only in the amorphous phase but also in the crystalline core. Among comonomers, butene-1 is favorably incorporated in the crystalline phase with the expansion of the crystal lattice, and the amount of comonomer in the crystal is comparable with that in the amorphous phase. Ethylene, hexene-1 and octene-1 were also found to be included into the crystal, but the degree of inclusion in the crystal was much less than that of butene-1.

Considering both the continuous increase of the weight loss and the saturation of the molecular weight decrease of the residue during an etching time-course, a plausible mechanism for the FNA degradation of the propylene copolymers was proposed.     

Behavior of electrical resistance of SiC<Subscript>CVD</Subscript> fiber and development of micro-heater with SiC<Subscript>CVD</Subscript> fiber

Behavior of electrical resistance was examined in room temperature and elevated temperatures up to 1000 °C for two types of SiC_CVD fibers with diameters of 140 and 70 μm, respectively. The results showed that electrical resistance showed a good linear relationship with the length of fibers. Electrical resistance decreased as temperature increased, besides, temperature coefficient of electrical resistance was a minus constant, −5.2 × 10⁻⁴ °C⁻¹ except that in the first heating. In the first heating, electrical resistance and temperature coefficient increased and had a peak in the range of 550–700 °C owing to the burning of the carbon-rich layer on the fiber surface. It suggested that behavior of electrical resistance of the fibers depended mainly on the carbon core and the carbon-rich layer. It was confirmed that SiC_CVD fiber could be used as heating elements for micro-heater and finally a micro-heater using SiC_CVD fiber as heating elements was developed.