Sinterability and properties of Ti(N1−x,O x ) y -(V,Ta)C-Ni sintered alloys having a golden colour

The effect of oxygen and carbide addition on the sinterability of TiN _y (0.42<y<1)-Ni alloys, in which part of the nitrogen is replaced by oxygen was investigated. It was found that sinterability increased as the oxygen and carbide content increased, but the strength of the resultant sintered alloys was significantly reduced due to the presence of Ni₃Ti and Ti₂O₃ phases when the oxygen content exceeded 50 mol %. The sintered alloy with the highest hardness was found whenx=0.7,y=0.78 and the (V,Ta)C content was 18% by weight and this alloy was characterized by having a low density, good corrosion resistance and the colour of gold.     

Development of flexible organic light‐emitting diode on barrier film and roll‐to‐roll manufacturing

To come out with a successful organic light‐emitting diode (OLED) lighting business, it is very important to have clear differentiation of OLED from LEDs. Flexible OLED has merits, such as capability to be mounted on the curved wall, which is not easy for LEDs to achieve the feature. There are several approaches to make flexible OLEDs especially among those plastic barrier films that can bring high level of flexibility, which could not be achieved by any conventional lighting method. In this paper, barrier films with various water vapor transmission rate values, including 10^{? 6} order, are applied, and the conditions to have almost no dark spot growth under 85 °C and 85% high temperature/humidity test are shown. Flexible OLED panels are manufactured with the world's first roll‐to‐roll equipment using plastic barrier film.     

Adaptive MAP receiver via the EM algorithm and message passings for MIMO-OFDM mobile communications

This paper proposes two new types of maximum a posteriori probability (MAP) receivers for multiple-input-multiple-output and orthogonal frequency-division multiplexing mobile communications with a channel coding such as the low-density parity-check code. One proposed receiver employs the expectation-maximization algorithm so as to improve performance of approximated MAP detection. Differently from a conventional receiver employing the minimum mean-square estimation (MMSE) algorithm, it applies the recursive least squares (RLS) algorithm to the channel estimation in order to track a fast fading channel. For the purpose of further improvement, the other proposed receiver applies a new adaptive algorithm that can be derived from the message passing on factor graphs. The algorithm exploits all detected signals but one of targeted time, and can gain a considerable advantage over the MMSE and RLS. Computer simulations show that the first proposed receiver is superior in channel-tracking ability to the conventional receiver employing the MMSE. Furthermore, it is demonstrated that the second proposed receiver remarkably outperforms both the conventional and the first proposed ones.     

Effect of 1 alpha-hydroxyvitamin D3 on serum levels of thyroid hormones in hyperthyroid patients with untreated Graves' disease

We performed a randomized, open prospective study to determine the effect of 1 alpha-hydroxyvitamin D3 [1 alpha (OH)D3] on hyperthyroidism in patients with untreated Graves' disease. At the time of entry into the study, 30 patients were randomly assigned to receive a daily dose of 30 mg methimazole (MMI) (group A, n = 15) or the same dose of MMI supplemented with 1.5 micrograms 1 alpha (OH)D3 (group B, n = 15). These treatment regimens were continued for 24 weeks, and physicians were allowed to adjust MMI dosage during follow-up visits. Blood samples were collected, and serum concentrations of free triiodothyronine (FT3), free thyroxine (FT4), T3, T4, thyrotropin (TSH), alkaline phosphatase (ALP), and TSH-receptor antibody (TRAb) were determined. During the follow-up periods, all patients became euthyroid. The dose of MMI was not significantly different between these two groups. In contrast, decreases in mean serum FT3 and FT4 levels, as well as in mean serum T3 and T4 levels, were greater in group B. Correspondingly, the reciprocal increase in the mean TSH level was more prominent in group B. Mean TRAb levels did not differ between the two groups. Mean serum ALP levels in group B were significantly lower than in group A at 24 weeks. Thus, we suggest that concomitant administration of 1 alpha (OH)D3 is useful for treating hyperthyroidism in patients with Graves' disease.     

Neutrophilic myelofibrosis; a case report

A 53-year-old male was admitted to our hospital with abdominal pain. Physical examination revealed marked splenomegaly. The white blood cell count increased to 5.8 x 10(4)/microliters. Bone marrow biopsy showed hypercellularity with a moderate increase in reticulin fiber. Chromosomal analysis showed 47, XY, +9q-, -9q- without Ph1 chromosome and bcr-abl rearrangement. MCNU therapy was successful in reducing the white blood cell count and splenomegaly. It is likely that the diagnosis of our patient is compatible with the neutrophilic myelofibrosis described by Stewart, et al.     

Iterative receiver employing phase noise compensation and channel estimation for millimeter-wave OFDM systems

This paper proposes an iterative OFDM millimeterwave receiver employing low-complexity decision-directed phase noise compensation (DD-PNC) to alleviate degradation due to the phase noise. High bit-rate OFDM transceivers based on the single-chip Si RF-CMOS IC technology in the 60-GHz millimeter-wave band have been extensively studied for wireless personal area network (WPAN) systems, and the relatively large phase noise in the phase locked loop (PLL) synthesizer severely degrades transmission performance. The proposed OFDM receiver iterates DD-PNC and decision-directed channel estimation (DDCE) by exploiting the output of the channel decoder. DDPNC estimates the phase noise each sampling time by using the decoder output, and then it removes the estimate from a time-domain received signal. In addition, DDCE estimates a channel impulse response by using the compensated received signal. Computer simulations demonstrate that in the 64QAM modulation with the coding rate of 3/4, the proposed receiver with DD-PNC and DDCE can perfectly remove the phase noise of -85 dBc/Hz at 1 MHz offset, and that it can alleviate the degradation of the channel estimation due to the phase noise.     

Production technology of large-area multicrystalline silicon solar cells

In 1996 a conversion efficiency of 17.1% had been obtained on 15 cm×15 cm mc-Si solar cell. In this paper, large-scale production technology of the high-efficiency processing will be discussed. Enlarging reactive ion etching (RIE) equipment size, technology of passivation, and fine contact grid with low resistance by screenprinted metallization, which is firing through PECVD SiN, have been investigated.     

Development of 500-kV XLPE cables and accessories for long distanceunderground transmission line. III. Electrical properties of 500-kVcables

500-kV XLPE-insulated cable with an insulation thickness of 27 mm has been developed for long-distance transmission lines. Basic studies on 500-kV XLPE cable have shown that contaminants in the insulation may be the factor determining electrical performance. This hypothesis is justified by the good correlation obtained between statistical estimations of the size of the largest contaminant in the insulation and the electrical characteristics of full-sized cables. Voltage-withstand and long-term tests have confirmed the design values for minimum breakdown stress, for AC and impulse voltage, and for the degradation coefficients     

Model study on the formation of fuel NOx from cokes on combustion: Effect of metal oxides

To elucidate the process of ‘fuel NO_x’ formation from cokes and chars on combustion, carbons obtained from urea-resin and melamine-resin were subjected to combustion under a stream of pure oxygen at temperatures between 600 °C and 1000 °C. The carbons subjected to combustion without any additives produced a relatively small amount of NO_x, but, it was observed that the NO_x formation predominated at lower temperatures of combustion. When the combustion was carried out with the addition of metal oxides, such as iron oxides and cupric oxide, the amount of NO_x formed increased markedly but silicon dioxide had no such effect.     

Coherent frequency hopping multiple access (CFHMA) with multiuserdetection for mobile communication systems

This paper proposes a new multiple-access (MA) scheme, coherent frequency hopping MA (CFHMA) with multiuser detection, which effectively obtains the diversity effect for realizing spectrally efficient mobile communications, CFHMA is fundamentally equivalent to a coherent fast frequency hopping frequency-division MA (FDMA) that incorporates low spreading factor direct-sequence (DS) code-division MA (CDMA). Multiple users occupy the same frequency band, and they are simultaneously detected by multiuser detection. There are several implementations of CFHMA. Two major techniques are introduced: coherent hybrid DS fast FH (FFH) (CHYB-DS-FFH) and interleaved FH (IFH). This paper focuses on IFH and discusses its principle of operation, transmission system configuration, and performance aspects. The results suggest the feasibility of a spectrally efficient mobile radio system