Multiagent analysis for effect of cogeneration spread in an electricity market

In this paper, in order to investigate the effect of scenarios in which cogeneration spreads in an electricity market we constructed a multi‐agent model of an electricity trading market with power distribution and power generation agents. In this model, we analyzed the effect of reducing power generation surplus facilities on market price formation and stability through computer experiments. As a result of the experimental simulations, the market price was decreased by the increase of sell bids according to the demand reduction by the spread of cogeneration, and by the increase of commercial use of cogeneration facilities, the market price was more economical and stable because such agents supplied more electricity generated by surplus cogeneration. However, if power generation agents reduced the number of power generating facilities when the number of power distribution agents' cogeneration facilities was not significant, the fluctuation of market price grew larger. We confirmed that the spread of cogeneration played an important role in stabilizing market price formation. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 156(2): 61–74, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20353     

Improved Aging Characteristics of NTC Thermistor Thin Films Fabricated by a Hybrid Sol–Gel–MOD Process

Negative temperature coefficient thermistor oxide thin films with improved aging characteristics are described. Better thermal stability has been achieved by incorporating sol–gel techniques with metallo-organic decomposition methods. A compositional range was identified whereby borosilicate may incorporate into the thermistor oxides, forming nanocomposites showing thermistor electrical characteristics. Thermistor thin films, with composition Ni_0.48Co_0.24Cu_0.6Mn_1.68O₄·0.22SiO₂·0.15B₂O₃ were deposited onto glass substrates from a solution containing organic transition metal salts, tetraethyl orthosilicate and triethyl borate. Electrical resistance measurements verified characteristic thermistor behavior. Nanocomposite thin films exhibited a factor of four improvement as compared with pure oxides after aging at 150°C for 500 h.     

Survival of a patient with postinfarction ventricular septal defect following venoarterial bypass with centrifugal pump and reoperation for residual shunt

A 61-year-old man was hospitalized because of circulatory collapse due to postinfarction ventricular septal defect. As his hemodynamic condition deteriorated despite intraaortic counterpulsation, he underwent patch closure of VSP and patch reconstruction of the anterior left ventricular wall concomitant with coronary artery bypass grafting to the circumflex lesion immediately after admission. Femorofemoral circulatory assist with centrifugal pump was necessitated to wean from cardiopulmonary bypass because of severe left ventricular dysfunction. Circulatory assist was controlled to maintain mixed venous oxygen saturation of more than 70% under mild hypothermia. On the second postoperative day (POD), increased oxygen saturation from right atrium to pulmonary artery developed (Qp/Qs = 2.1). Further surgery was performed on an emergency basis for additional patch closure of VSP. Then he was successfully weaned from cardiopulmonary bypass successfully. The patient was extubated on the 14th POD and was ambulatory when he discharged on the 56th POD. Immediate surgical intervention should be performed for the patient with postinfarction ventricular septal defect when the hemodynamic state deteriorates under intraaortic counterpulsation.     

Changes in plasma dopamine-beta-hydroxylase activity during the perioperative period of cardiac surgery: an index of sympathetic nerve activity

To evaluate the usefulness of plasma dopamine-beta-hydroxylase (DBH) activity as an index of sympathetic nerve activity during cardiac operations, we examined the serial changes in plasma DBH activity, in relation to the plasma noradrenaline (NA) level and hemodynamic parameters, in patients who underwent cardiac surgery. The plasma DBH activity decreased significantly after cardiopulmonary bypass, and remained low during dopamine (DA) infusion until 72 h after the operation. However, recovery of the hemodynamic parameters, being the mean arterial pressure, heart rate and cardiac index, was seen as early as 1-3 h postoperatively. It was therefore assumed that the plasma DBH activity takes a long time to recover after an operation. The time-course changes in the plasma NA level were quite different from the changes in DBH activity, with an apparent negative correlation being observed between them. Thus, there is a possibility that exogenously administered DA, as well as increased plasma NA, might inhibit DBH activity during cardiac surgery. Moreover, since catecholamines are often administered upon completion of cardiac surgery, measurement of the plasma catecholamine level would be inappropriate for evaluating real sympathetic nerve activity. From the results of this study, it is surmised that measurement of the plasma DBH activity could be useful for estimating the intrinsic sympathetic nerve activity of patients who have undergone cardiac surgery.     

Word-line architecture for highly reliable 64-Mb DRAM

A unique word-line voltage control method for the 64-Mb DRAM and beyond is proposed. It realizes a constant lifetime for a thin gate oxide. This method controls word-line voltage and compensates reliability degradation in the thin gate oxide for cell-transfer transistors. It keeps the time-dependent dielectric breakdown (TDDB) lifetime constant under any conditions of gate oxide thickness fluctuation, temperature variation, and supply voltage variation. This method was successfully implemented in a 64-Mb DRAM to realize high reliability. This chip achieved a 10⁵ times reliability improvement and a 0.3~1.8-V larger word-line voltage margin to write ONE data into the cell     

A quick intelligent page-programming architecture and a shieldedbitline sensing method for 3 V-only NAND flash memory

This paper describes a quick intelligent page-programming architecture with a newly introduced intelligent verify circuit for 3 V-only NAND flash memories. The new verify circuit, which is composed of only two transistors, results in a simple intelligent program algorithm for 3 V-only operation and a reduction of the program time to 56%. This paper also describes a shielded bitline sensing method to reduce a bitline-bitline capacitive coupling noise from 700 mV to 35 mV. The large 700 mV noise without the shielded bitline architecture is mainly caused by the NAND-type cell array structure. A 3 V-only experimental NAND flash memory, developed in a 0.7-μm NAND flash memory process technology, demonstrates that the programmed threshold voltages are controlled between 0.4 V and 1.8 V by the new verify circuit. The shielded bitline sensing method realizes a 2.5-μs random access time with a 2.7-V power supply. The page-programming is completed after the 40-μs program and 2.8-μs verify read cycle is iterated 4 times. The block-erasing time is 10 ms     

Performance Analysis of Total Power Consumption in Linear Multi-hop Networks

A multi-hop network transmits the data packets through some relay nodes. In the case of equidistant transmission, it can achieve lower transmission power than a single-hop network. On the other hand, the relay nodes also have their own power consumption that does not contribute to transmission. Therefore, the total power consumption, which are the transmission power of the relay nodes and their own power consumption, can be more than that of the direct communications in the case of numbers of relay nodes and values of power consumption. In this paper, we derive theoretical expression of total power consumption with ARQ (auto repeat request) for packetized transmitted data for linear topology multi-hop networks under path loss and shadowing environments. Moreover, we consider the maximum hops which is better than direct communications in total power consumptions and the optimum hops which minimizes them and evaluate their performance using numerical calculation.     

SODEL FET: novel channel and source/drain profile engineering schemes by selective Si epitaxial growth technology

In this paper, novel channel and source/drain profile engineering schemes are proposed for sub-50-nm bulk CMOS applications. This device, referred to as the silicon-on-depletion layer FET (SODEL FET), has the depletion layer beneath the channel region, which works as an insulator like a buried oxide in a silicon-on-insulator MOSFET. Thanks to this channel structure, junction capacitance (C/sub j/) has been reduced in SODEL FET, i.e., C/sub j/ (area) was /spl sim/0.73 fF//spl mu/m/sup 2/ both in SODEL nFET and pFET at Vbias =0.0 V. The body effect coefficient /spl gamma/ is also reduced to less than 0.02 V/sup 1/2/. Nevertheless, current drives of 886 /spl mu/A//spl mu/m (I/sub off/=15 nA//spl mu/m) in nFET and -320 /spl mu/A//spl mu/m (I/sub off/=10 nA//spl mu/m) in pFET have been achieved in 70-nm gate length SODEL CMOS with |V/sub dd/|=1.2 V. New circuit design schemes are also proposed for high-performance and low-power CMOS applications using the combination of SODEL FETs and bulk FETs on the same chip for 90-nm-node generation and beyond.