BIDIRECTIONAL TRANSMISSION OF ADDRESSED AUDIO SIGNAL THROUGH GI MULTIMODE OPTICAL FIBRES

This paper describes two types of bidirectional addressed audio signal transmission systems where the square-wave frequency modulation (SWFM) and intensity modulation (IM) are used to obtain the optical SWFM signals generated from LEDs at 850 nm. The first one is an addressed audio signal transmission network of tree structure. The sender and auxiliary receiver in the centre are connected to four terminals, each consisting of a receiver and an auxiliary sender, through pairs of optical fibres and an optical splitter used as an optical signal distributor. The second one is a new type of full-duplex one-to-one communication system. The sender and auxiliary receiver in one terminal are connected to the receiver and auxiliary sender in the other terminal through an optical fibre and a pair of directional couplers. Although LEDs in the second system deliver optical SWFM signals at the same wavelength of 850 nm at the same time, the communications are satisfactory because there is no interference from one LED to the other. In both the first and second experimental systems, the audio signal, address, and SWFM carrier occupy 10 Hz to 20 kHz, 65 kHz to 710 kHz, and 6 MHz, respectively. The SNR and distortion were 62 dB and 0.4 per cent, respectively.     

Fault-tolerant decentralized H-infinity control for multi-channel systems using homotopy method

This paper considers a fault-tolerant decentralized H-infinity control problem for multi-channel linear time-invariant systems. The purpose is to design a decentralized H-infinity output feedback controller to.stabilize the given system and achieve a certain H-infinity performance requirement both in the normal situation and in the situation where any one of the local controllers fails. The designed problem is reduced to a feasibility problem of a set of bilinear matrix inequalities （BMIs）. An algorithm is proposed to solve the BMIs. First, the normal situation is considered where all the local controllers are functioning. The local controllers are obtained from a standard centralized H-infinity controller by using a homotopy method imposing a structural constraint progressively. Secondly, the above case is extended to the one where any one of the local controllers fails. We again use a homotopy method where the coefficient matrices of the failed controller are decreased progressively to zero. The efficiency of the proposed algorithm is demonstrated by an example.     

MEASUREMENT OF THE RELATIVE TASTE INTENSITY OF SOME L-α-AMINO ACIDS AND 5'-NUCLEOTIDES

SUMMARY— Intensity of glutamate-like and/or inosinate-like taste (umami in Japanese) of various flavor amino acids and flavor nucleotides was studied using sensory analysis and always found proportional to that of monosodium glutamate (MSG) and disodium 5'-inosinate (IMP), respectively. By application of this fact to a previously obtained equation expressing the relationship between the taste intensity of MSG-IMP mixture and that of MSG alone, the intensity of umami of the mixture of any flavor amino acids and nucleotides could be expressed as an elementary equation: y = u +γ uv, where u and v are the concentrations of amino acids and nucleotides in terms of the concentrations of MSG and IMP, respectively, in the mixture; y is the equivalent concentration of MSG alone; and γ is a positive constant. Interrelationships within each group of substances were additive.     

Study on the transport of suspended sediment in an open channel flow with permeable spur dikes

The transport of suspended sediment in rivers with spur dikes is an important issue for bank protection and environmental management. Laboratory experiments were performed to study the characteristics of the flow and the transport of suspended sediment in an open channel with permeable dikes. Firstly, the essentials of these characteristics were studied by comparing results of flume experiments on permeable and impermeable dikes. The influence of the aspect ratio (d/l) of the interval between dikes (d) to the length of dikes (l) on these characteristics was then investigated. In these experiments, the properties of horizontal eddies, turbulence structures, and suspended sediment concentrations were studied. The results show that the development of large-scale horizontal eddies requires some distance in a shear layer for permeable dikes, although they are periodically generated from the first dike in the case of impermeable dikes. The basic structures of horizontal eddies are independent of the aspect ratio in the equilibrium region for permeable dikes. The suspended sediment concentrations for cases of permeable dikes gradually decrease between the several upstream dikes and they approach a uniform distribution in the downstream region, although those in the case of the impermeable dikes are relatively uniform in the downstream direction.     

Dental application of polyfunctional urethane comonomers to composite resin veneering materials

Urethane monomer/diluent monomer mixtures were used in dental composite resin veneering materials filled with various ratios of powder (filler)/liquid (comonomer), P/L. Hardness values of unfilled resins containing benzoyl peroxide only (BP0; 0.5 wt%), and filled resins (included trimethylol propane trimethacrylate (TMPT) composite filler) were tested. Significant increases in hardness were obtained with the use of TMPT composite filler in the resins. Also, their modulus values measured by bend test showed an increasing trend, compared to a commercial composite resin veneering material (a control sample; CONT) with a lower filler content (50 wt%). The DME–DPMDC/HPDM comonomer (dimethacryloxyethyl diphenylmethane-4,4-dicarbamate/hydroxypropyl dimethacrylate), which showed a smaller fraction of surface porosity, gave greater mechanical strength values at P/L ratios of 0.55 (17.8 wt% filler content) to 1.20 (27.3 wt%) than a CONT resin. The coefficient of thermal expansion was smaller in urethane-based filling materials than a CONT resin. Also, greater activation energy of thermal decomposition was observed in the resin samples with P/L ratio 0.75 to 1.20 than in a CONT resin. Thermally-induced decomposition occurred with smaller weight loss in the experimental filled resins than in a CONT resin.     

The Effective Pore Radius of Screen Wicks

The effective pore radius in screen-wick heat pipes was investigated, which is very important for the prediction of maximum heat transfer rates due to capillary limitation. An equation for the effective pore radius of the screen wicks was derived based on the model of the screen geometry. The capillary height for stainless steel and phosphor bronze screens was measured using water, ethyl alcohol, and Freon 113 as the test liquids. The effect of surface treatment (acid cleaning and oxidation) on the capillary height was also examined. From the comparison of the experimental data for water and ethyl alcohol with those for Freon 113, it was indicated that the contact angle was 24.2° for water and 16.9° for ethyl alcohol. Consequently, it was found that the effective pore radius of the screen wicks could be predicted fairly well from the expression presented in this study, and that the contact angle should be taken into consideration to evaluate the maximum capillary pressure accurately.     

ANALYSIS OF DIFFUSE PARENCHYMAL LIVER DISEASE BY LIVER SCINTIGRAMS: DIFFERENTIAL DIAGNOSIS USING FUZZY INFERENCE AND GENETIC ALGORITHM IN NUCLEAR MEDICINE

In nuclear medicine, diagnosis of diffuse parenchymal liver disease such as chronic hepatitis (CH) or liver cirrhosis (LC) is evaluated by size and distortion of the liver, distribution of radioactive tracer in the liver, size and activities of the tracer in the spleen, the degree of visualization of the bone marrow, etc. using colloid liver scintigraphy, It is not difficult to read a scintigram for a typical pattern; however in some cases it is difficult to distinguish between normal and CH or CH and LC visually. Therefore, we tried to use fuzzy inferences to perform differential diagnosis. Using fuzzy inference, differential diagnosis of LC could be performed up to 100%, but those of CH and Severe fibrosis (SF) could not be performed sufficiently. Therefore genetic algorithm was tried to determine the fuzzy rules. By combining genetic algorithm and fuzzy inference, CH, SF, and LC could be differentiated to the degree 70%, 60%, and 100%, respectively.     

Inhibitory Potency of Plant Antinutrients towards the In Vitro Digestibility of Buckwheat Protein

The inhibitory potency of dietary fiber sources, tannins, phytate, and a protein protease inhibitor on the in vitro pepsin-pancreatin digestibility of protein was compared. The protein inhibitor exhibited the highest inhibitory capacity among the substances examined; and phytate the lowest. Our findings suggest that the inhibition of the digestion of dietary sources of plant proteins by such factors as fiber and tannins, in addition to the protein protease inhibitors, may also be taken into account.     

Fault-tolerant decentralized H-infinity control for multi-channel systems using homotopy method

This paper considers a fault-tolerant decentralized H-infinity control problem for multi-channel linear time-invariant systems. The purpose is to design a decentralized H-infinity output feedback controller to stabilize the given system and achieve a certain H-infinity performance requirement both in the normal situation and in the situation where any one of the local controllers fails. The designed problem is reduced to a feasibility problem of a set of bilinear matrix inequalities (BMIs). An algorithm is proposed to solve the BMIs. First, the normal situation is considered where all the local controllers are functioning. The local controllers are obtained from a standard centralized H-infinity controller by using a homotopy method imposing a structural constraint progressively. Secondly, the above case is extended to the one where any one of the local controllers fails. We again use a homotopy method where the coefficient matrices of the failed controller are decreased rogressively to zero. The efficiency of the proposed algorithm is demonstrated by an example.