QDPSK signal transmission performance with postdetection selectiondiversity reception in land mobile radio

The bit error rate (BER) performance of 16-128 kb/s Nyquist raised-cosine filtered quaternary differential phase-shift keying (RC-QDPSK) signal transmission was experimentally investigated. Two-branch postdetection selection diversity reception was employed. Measured results are presented for the BER performance due to additive white Gaussian noise (AWGN), cochannel interference, and multipath channel delay spread. Field BER measurements were also conducted at a carrier frequency of 1.45 GHz in an area characterized by high-rise buildings and in an area surrounded by mountains. The results show that postdetection selection diversity is a simple yet powerful technique to improve the BER performance in fading mobile radio channels     

InGaAs enhancement-mode MISFETs using double-layer gate insulator

In this letter we describe the fabrication of enhancement-mode MISFETs on InGaAs grown by liquid-phase epitaxy (LPE) using an anodic Al2O3/anodic native oxide double layer as a gate insulator. The normally-off device of 10 ?m gate length shows the effective channel mobility of 1400 cm2/Vs. The interface state density distribution of this double-layer MIS of InGaAs is also reported. The density of 2 × 1013 cm?2 eV?1 at Ec ?0.057 eV and the minimum of 8 × 1011 cm?2 eV?1 near midgap are measured from C/V characteristics.     

Effects of Channel Width on Stress Enhancement for Damascene-Gate nFETs With Top-Cut Tensile-Stress Liner

This letter provides channel-stress behavior results induced by a local strain technique which consists of the process combination of a damascene-gate and top-cut tensile stress SiN liner for narrow channel-width nFETs using 3-D stress simulations and demonstrations. The dummy-gate removal, which is an intrinsic step in the damascene-gate process, is found to enhance tensile channel stress along the gate length at the edge of the channel beside the shallow trench isolation. In consequence of a mobility boost due to the high tensile stress, drain-current enhancement in the saturation is achieved for the damascene-gate nFETs with the narrow channel width and short gate length.     

BER performance owing to random FM noise for QDPSK mobile radio with diversity reception

BER performance owing to random FM noise is investigated for QDPSK with postdetection selection diversity reception in a multiplicative Rayleigh fading environment. Experimental results for 16 Kbit/s QDPSK using a Rayleigh fading simulator are reported. It is shown that diversity reception can significantly reduce the impact of random FM noise.<>     

Automatic Variable Field Chopper Control System for Electric Railcars

1) The principle of the automatic variable field (AVF) chopper control system, 2) analysis of field characteristics, the field intensity to the chopper-conduction ratio, 3) applying the AVF system to high voltage, large capacity, high frequency chopper equipment, and 4) test results on the Chiyoda Line of Teito Rapid Transit Authority are discussed.     

Bone composite behaviour: effects of mineral-organic bonding

The mechanical properties of a composite material rely not only on the volume fraction, orientation and properties of the individual constituents, but upon their bonding interactions as well. This study examines the role of bonding between the mineral and organic constituents of bovine compact bone. Intact and completely demineralized samples were tested in tension following treatment in varying ionic strength sodium chloride or phosphate ion containing buffers to examine the interfacial bonding forces between bone's constituents. Phosphate ion treatment caused a reduction in the mechanical properties of intact samples but not in the demineralized samples. A sodium chloride solution with ionic strength equal to that of the phosphate ion buffer did not alter the mechanical properties of the intact or demineralized samples. Ash weight analysis, calcium probe measurements and SDS-gel electrophoresis indicated intact samples were not demineralized nor were bone structural proteins removed during treatment. Data suggest that the reduction in the mechanical properties of intact samples with phosphate ion treatment was due to an alteration in the interfacial bonding between the mineral and organic constituents of bone. Phosphate ions can compete with the negative domains of organic constituents for calcium binding sites of bone mineral and thereby interrupt or partially debond the interactions between the mineral and organic constituents of bone.     

Sequence dependence of the hyperthermic potentiation of carboplatin-induced cytotoxicity and intracellular platinum accumulation in HeLa cells

We have examined the enhancement of cytotoxic effects of cis-diammine-1,1-cyclobutane dicarboxylate platinum(II) (carboplatin) by hyperthermia in HeLa cells using different regimes of timing and sequence. The results were compared with those obtained with cis-diamminedichloroplatinum(II) (cisplatin). We found that cisplatin simultaneously combined with heat was the most cytotoxic toward HeLa cells of the various timing and sequencing conditions studied. On the other hand, for carboplatin, drug treatment immediately following or during heat exposure showed the greatest effect. Intracellular platinum concentration in HeLa cells treated with heat before carboplatin showed a 2.75-fold increase over that in cells treated with the drug alone. The ratios for carboplatin given before, or during heating, were 0.67 and 1.42 respectively. Simultaneous exposure of cells to cisplatin and heat led to a 1.64-fold enhancement in cisplatin accumulation, compared to 0.92- and 1.24-fold increase for cells treated with cisplatin before and after heat respectively. Although each drug exposure prior to heat was less cytotoxic toward HeLa cells than any other heat/drug combination sequences, the platinum concentration was less than seen with each drug alone. Even though heat exposure prior to and during carboplatin showed a similar toxicity, platinum concentration in cells treated with heat prior to carboplatin was higher than that in cells treated with heat and carboplatin simultaneously. Thus, increased cytotoxicity cannot always be explained on the basis of intracellular platinum concentration. It is clear however that, differing from cisplatin, exposure of cells to heat prior to or during carboplatin administration results in the greatest cell kill.     

Intermediate lymphocytic lymphoma with multiple lymphomatous polyposis of the gastrointestinal tract

1. Erythromycin administration is associated with gastrointestinal problems, disturbed gastrointestinal motility and emesis. This study in the dog investigates the underlying mechanisms. 2. Intestinal myoelectrical activity and the occurrence and latency of emesis were recorded in eight conscious dogs. All drugs were administered intravenously. 3. Erythromycin (7 mg kg-1) increased contractions of the proximal small intestine, and caused emesis in all fasted dogs and in 5 dogs after food. Atropine (50 mg kg-1 min-1) and hexamethonium (10 mg kg-1 h-1) partially inhibited the GI motility effects but did not significantly reduce emesis. 4. Metoclopramide at a high dose (2 mg kg-1 h-1) reduced the incidence of emesis in the presence of increased intestinal motility, but a low dose (150 micrograms kg-1 h-1) was ineffective. 5. A 5-hydroxytryptamine3 (5-HT3) receptor antagonist, MDL 72222 (1 mg kg-1), reduced emesis when given alone and combined with metoclopramide (low dose). The 5-HT4 receptor agonist BRL24924 (Renzapride, 1 mg kg-1) had no effect on emesis either alone in combination with metoclopramide. 6. In conclusion, erythromycin-induced GI motility disturbances and emesis are not causally related. Whereas the increase in intestinal smooth muscle activity is possibly cholinergically mediated, emesis occurs at least in part via a 5-hydroxytryptaminergic mechanism, but does not involve the dopamine system.     

1993 Intercomparison of Photometric Units Maintained at NIST (USA) and PTB (Germany)

A bilateral intercomparison of photometric units between NIST, USA and PTB, Germany has been conducted to update the knowledge of the relationship between the photometric units disseminated in each country. The luminous intensity unit (cd) and the luminous flux unit (lm) maintained at both laboratories are compared by circulating transfer standard lamps. Also, the photometric responsivity s_v is compared by circulating a V(λ)-corrected detector with a built-in current-to-voltage converter. The results show that the difference of luminous intensity unit between NIST and PTB, (PTB-NIST)/NIST, is 0.2 % with a relative expanded uncertainty (coverage factor k = 2) of 0.24 %. The difference is reduced significantly from that at the 1985 CCPR intercomparison (0.9 %). The difference in luminous flux unit, (PTB – NIST)/NIST, is found to be 1.5 % with a relative expanded uncertainty (coverage factor k =2) of 0.15 %. The difference remained nearly the same as that at the 1985 intercomparison (1.6 %). These results agree with what is predicted from the history of maintaining the units at each laboratory.