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We proposed and demonstrated a resonant-tunnelling hot electron transistor (RHET) in 1985, and developed a multi-emitter RHET in 1993, enabling us to make an SRAM cell and multi-input logic gates using a single transistor. Through the development of these quantum tunnelling transistors, we have created the technology needed to fabricate precisely controlled quantum well structures, and have mostly understood the physics behind quantum well structures. Although this technology has been successfully used to develop heterostructure transistors and quantum well laser diodes, RHETs cannot yet be used in practical applications. One reason is that the RHET should be cooled down to about 77 K and its functionality is insufficient to replace conventional semiconductor devices. To make these RHETs practical for future use in cryoelectronic systems, integration with complementary-HEMT logic circuits or developement of new architecture circuits will be essential. There are also other important areas of research for us. One is to develop room temperature quantum functional bipolar transistors. Another is to develop quantum box devices based on the RHET technology, searching ultrasmall limit of electron devices. These research will be also useful in the development of photonic devices, such as quantum dot lasers and new photonic memory devices.

The magnetic hyperfine splitting frequencies of (i) $^{57}\mathrm{Ni}$ in Fe ${(}^{57}$NiFe), (ii) $^{57}\mathrm{Ni}$ in Ni ${(}^{57}$NiNi), and (iii) $^{59}\mathrm{Fe}$ in Fe ${(}^{59}$FeFe) were measured with the technique of nuclear magnetic resonance on oriented nuclei (NMR-ON) at low temperatures. The NMR-ON spectra were observed by detecting the \ensuremath{\beta}-ray asymmetries. The resonance frequencies at zero external magnetic field were deduced from the extrapolation of the external field dependence of the resonance frequencies: \ensuremath{\nu}${(}^{57}$NiFe)=94.23(2) MHz, \ensuremath{\nu}${(}^{57}$NiNi)=30.02(4) MHz, and \ensuremath{\nu}${(}^{59}$FeFe)=57.719(11) MHz. With the known hyperfine fields of ${\mathit{B}}_{\mathrm{HF}}$(NiNi)=-7.406(8) T and ${\mathit{B}}_{\mathrm{HF}}$(FeFe)=-33.82(3) T, the magnetic moments of $^{57}\mathrm{Ni}$ and $^{59}\mathrm{Fe}$ were determined to be \ensuremath{\mu}${(}^{57}$Ni)=-0.7975(14)${\mathrm{\ensuremath{\mu}}}_{\mathit{N}}$ and \ensuremath{\mu}${(}^{59}$Fe)=-0.3358(4)${\mathrm{\ensuremath{\mu}}}_{\mathit{N}}$. The precise value of the hyperfine field of ${\mathit{B}}_{\mathrm{HF}}$${(}^{57}$NiFe) was also deduced as -23.25(5) T. The measured values of the magnetic moment are compared with those based on the shell model. \textcopyright{} 1996 The American Physical Society.

This paper discusses the present status of efforts made by Japanese electric utilities, including plans to realize the optimal combination of fossil power and hydraulic power with nuclear power as the main power source, the increase of energy use efficiency, studies on CO 2 recovery and fixation, and international cooperation related to these efforts. Also, as an example of efforts made by Japanese electric utilities, this paper discusses the efforts of Kansai Electric Power Company to prevent global warming. This discussion centers on attempts to make technological breakthroughs, such as studies on CO 2 recovery and fixation, and international joint research project on the development of tropical forests regeneration technology.

Particle confinement time {tau}{sub p} has been obtained from measurements of poloidal and toroidal distributions of H{alpha} and Lyman {alpha} emissions in CHS. These particle confinement times range between 1.5 and 4ms at a constant line-averaged density of 3 x 10{sup 13}cm{sup -3} for both cases of limiter- and divertor-dominated NBI plasmas with Ti-gettering. In these cases the energy confinement time {tau}{sub E} were between 2 and 3ms. The density decay characteristic time {tau}{sub p}{sup *} and global recycling coefficient R have been also measured for Ti-gettered plasmas and large {tau}{sub p}{sup *} values were observed. As a result high recycling rates (R>0.92) are obtained for a wide density range. For a limiter-dominated case of boronized plasmas (R{sub ax}=92.1cm) values of {tau}{sub p} were correlated with {tau}{sub E} and a linear correlation between them was found for normalized {tau}{sub E} to P{sup -0.58} which is a power degradation term in LHD empirical scaling. 6 refs., 9 figs.

AIMS--To evaluate the influence of interleukin-8 (IL-8) and other inflammatory cytokines (IL-6, IL-1 beta and tumour necrosis factor alpha (TNF alpha)) on the occurrence of peritonitis in patients receiving continuous ambulatory peritoneal dialysis (CAPD). METHODS--The study population comprised 12 patients with peritonitis, 33 without peritonitis, all undergoing CAPD, and five patients undergoing peritoneal catheter implantation. Cytokine concentrations in dialysis fluid were determined by immunoassay and their values compared. RESULTS--Concentrations of both IL-8 (median 147 pg/ml, range 20-2273 pg/ml; n = 12) and IL-6 (median 1120 pg/ml, range 96-10,600 pg/ml) were substantially elevated, while the IL-1 beta concentration was lower and TNF alpha was not detectable in patients at diagnosis. The IL-6 concentration was also elevated in patients undergoing catheter implantation as well as in those with peritonitis. The IL-8 concentration, however, was elevated only upon infection. Intraperitoneal production of IL-8 was evident on determination of paired serum and dialysis fluid cytokine concentrations, and immunostaining of peritoneal cells with monoclonal anti-IL-8 antibody. CONCLUSIONS--These results suggest that determination of the IL-8 concentration in dialysis fluid maybe useful as a specific marker for following patients with peritonitis receiving CAPD.

Transurethral vaporization of the prostate in saline (TURisV) is an innovative endoscopic surgical modality for the treatment of benign prostatic hyperplasia (BPH) that vaporizes prostate tissue using a uniquely designed mushroom electrode. TURisV promises instant hemostatic tissue ablation under saline irrigation and offers clinical advantages for endoscopic BPH operations. From July 2008 to February 2009, TURisV was performed in 17 cases with clinically significant BPH. Median operation time was 127.0 min and median volume of vaporized prostate tissue was 41.1 g. Median International Prostate Symptom Score improved from 20 to 4 after 12 months. Median maximum flow rate increased from 5.3 mL/s to 13.8 mL/s after 12 months. Postoperative median residual urine improved from 48.0 mL to 7.0 mL after 12 months. No changes in hemoglobin or electrolyte levels were seen postoperatively. Our results suggest that TURisV is a safe and efficacious treatment for BPH.

Nuclear magnetic resonance on oriented206BiFe and182ReFe has been measured using recoil implanted samples. Clearly resolved satellite structures were found for both systems. By annealing at an appropriate temperature, the resonance width was reduced. The satellite line structure for182ReFe was studied with various annealing temperatures. The ratio of the resonance strength changed with the annealing temperature. The resonances for182ReFe were also measured in external magnetic fields of 0.1, 0.2 and 0.4 T. The resonance frequencies for the satellite structure at an external magnetic field of 0.2 T were determined:v1=691.7(3),v2=684.4(2),v3=687.2(2) MHz for206BiFe;v1=231.15(5),v2=230.20(5) for182ReFe. The origin of the satellite structure is discussed. The effective relaxation time of182ReFe at 8 mK and external magnetic field of 0.2 T was determined to be 18.6(6) s using a single-exponential fit.

The negative differential resistance properties of resonant tunnelling barrier diodes with InGaAs quantum wells developed by us for new transistor applications are reviewed. The emphasis is on the peak current density and the peak-to-valley ratio. The tunnel barriers of InAlAs, pseudomorphic AlAs, AlAsSb and GaAsSb are studied. A simple theoretical calculation which includes the mid-gap band non-parabolicity of tunnelling electrons is described. These theoretical calculations show excellent agreement with the observed peak current density at 77 K and 300 K and a reasonable agreement with the valley current density at 300 K.

This paper presents a regression based daily peak load forecasting method with a transformation technique. In order to forecast the load precisely through a year, one should consider seasonal load change, annual load growth and the latest daily load change. To deal with these characteristics in the load forecasting, a transformation technique is presented. This technique consists of a transformation function with translation and reflection methods. The transformation function is estimated with the previous year's data points, in order that the function converts the data points into a set of new data points with preservation of the shape of temperature-load relationships in the previous year. Then, the function is slightly translated so that the transformed data points will fit the shape of temperature-load relationships in the year. Finally, multivariate regression analysis, with the latest daily loads and weather observations, estimates the forecasting model. Large forecasting errors caused by the weather-load nonlinear characteristic in the transitional seasons such as spring and fall are reduced. Performance of the technique which is verified with simulations on actual load data of Tokyo Electric Power Company is also described. >

CR3 (CD11b/CD18) functions both as an iC3b-receptor and as an adhesion molecule for cellular ligands such as ICAM-1. Although CR3 has been well characterized on phagocytic cells, much less is known about CR3 on lymphocytes. In this study, the expression of CR3 was examined on resting and stimulated B, T, and natural killer (NK) cells by three-color flow cytometry. Biotinylated anti-CR3 mAb and streptavidin-FITC were used in combination with anti-CD3 mAb conjugated with peridinin chlorophyll-alpha protein (PerCP) and phycoerythrin-labeled mAbs to CD4, CD8, CD19, or CD56. Among resting lymphocytes, CR3 was expressed on nearly all NK cells (CD56+CD3-), 1% of CD4+CD3+ helper T cells, 7% of CD8+CD3+ cytotoxic T cells, and 20% of B cells (CD19+). Among the 5% of T cells (CD3+) expressing CR3, the majority was CD56+. Incubation of PBMC for 30 min with PMA induced a three- to fivefold increase in CR3 expression on NK cells and a twofold increase on T cells but did not change the expression of CR3 on B cells. This effect of PMA was not blocked by the presence of cycloheximide, suggesting the presence of cytoplasmic (granule) stores of CR3 in these lymphoid cells resembling those previously reported in neutrophils and monocytes. When PBMC were incubated with rIFN-alpha, rIL-2, beta-glucan, or high concentrations of LPS, expression of CR3 on NK cells increased significantly, but > or = 4 hr of stimulation was required. Other cytokines (rIFN-gamma, rIL-1, rIL-4, rIL-6, TNF-alpha) and rC5a had no significant effect on CR3 expression. Among NK cells, both the CD56bright and the CD56dim cells expressed CR3, and the expression of CR3 on both of these NK cell subsets was increased in a similar manner by PMA. However, rIL-2 stimulated a greater increase in CR3 expression on CD56bright cells than on CD56dim cells. These studies suggest that CR3 expressed by NK cells or cytotoxic T cells resembles phagocyte CR3 in that cellular activation stimulates increased surface expression of CR3 derived from cytoplasmic reserves of the receptor.

The magnetic hyperfine splitting frequencies of90NbNi and93mMoNi in an external magnetic field of 0.2 T have been determined by the NMR-ON method to be 18.52(7) and23.73(10) MHz, respectively. With the assumption of Knight shift factorK=0 and with the knowng-factors, the hyperfine fields of90NbNi and93mMoNi were deduced asBHF(90NbNi)=-4.118(16) T andBHF(93mMoNi)=-3.491(33) T. The rather long spin-lattice relaxation time of 32(5) min was observed for90NbNi at an external magnetic field of 0.2T and8 mK.

Nuclear magnetic resonance on oriented76,77,82BrFe has been measured using recoil-implanted samples. The magnetic hyperfine splitting frequency of82BrFe in a zero external magnetic field has been determined to be 201.90(3) MHz. The resonances of76BrFe and77BrFe were also observed in an external magnetic field of 0.2 T asv(76BrFe)=340.9(3) MHz andv(77BrFe)=403.5(2) MHz. With the known values of theg-factors, the hyperfine fields have been deduced:B HF(82BrFe)=81.397(27) T,B HF(76BrFe)=81.38(7) T. Theg-factor of77Br was determined to be |0.6487(4)|.

A magnetic property of Pm as an impurity in PrNi single crystal was investigated by means of the low-temperature nuclear orientation of143,144Pm. The angular distribution of γ-ray anisotropies revealed that the direction of hyperfine field experienced by the nuclei lie in the (a, c) plane andmade an angle of 60° (5) or 240° (5) with respect to the crystallinec-axis. From the temperature dependence of the anisotropies the strength of the hyperfine field of Pm in PrNi was deduced to be 185(22)T. The hyperfine field of Co at the Ni site of PrNi was found to be less than 4T.

Nuclear factor (NF)-κB is a transcription factor that regulates cytokine and chemokine production in various inflammatory diseases, including bronchial asthma. IκB kinase (IKK) β is important for NF-κB activation in inflammatory conditions, and is possibly related to airway remodelling. Thus, inhibition of the IKKβ-NF-κB pathway may be an ideal strategy for the management of airway remodelling.We examined the effects of a newly synthesized IKKβ inhibitor, IMD-0354, in a chronic allergen exposure model of bronchial asthma in mice.A chronic mouse model was generated by challenge with house dust mite antigen (Dermatophagoides pteronyssinus). IMD-0354 was administrated intraperitoneally in therapeutic groups. Lung histopathology, hyperresponsiveness and the concentrations of mediators and molecules in supernatants of lung homogenates were determined.NF-κB activation was inhibited by prolonged periods of IMD-0354 administration. IMD-0354 reduced the numbers of bronchial eosinophils. IMD-0354 also inhibited the pathological features of airway remodelling, including goblet cell hyperplasia, subepithelial fibrosis, collagen deposition and smooth muscle hypertrophy. Inhibition of these structural changes by IMD-0354 was the result of the suppressing the production and activation of remodelling-related mediators, such as TGF-β, via inhibition of IKKβ. IMD-0354 inhibited IL-13 and IL-1β production, and it restored the production of IFN-γ. It also ameliorated airway hyperresponsiveness.IKKβ plays crucial roles in airway inflammation and remodelling in a chronic mouse model of asthma. A specific IKKβ inhibitor, IMD-0354, may be therapeutically beneficial for treating airway inflammation and remodelling in chronic asthma.

Synthesis and activity of the enzymatic equivalent of the sodium pump, Na,K-ATPase, are regulated by thyroid hormone in responsive tissues. The purpose of this study was to determine whether triiodothyronine (T3) regulates the level of the messenger RNA (mRNA) coding for Na,K-ATPase alpha- and beta-subunits in the heart. The expression of Na,K-ATPase mRNAs in in vitro myocardial cells was directly assayed by Northern and slot blot hybridization using Na,K-ATPase alpha- and beta-isoform-specific cDNA probes. Exposure of cultured neonatal rat cardiocytes to 10(-8) M T3 resulted in 1) threefold to fourfold increase in alpha 1- and beta 1-mRNA accumulation, with a maximum elevation at 48 hours, 2) sevenfold increase in alpha 2-mRNA accumulation with a peak elevation at 72 hours, and 3) transient threefold increase in alpha 3-mRNA within the first 24 hours followed by a deinduction thereafter. The increase in alpha 1-mRNA accumulation by T3 occurred over the physiological T3 concentration range with an EC50 of 5 x 10(-10) M. This was associated with a twofold increase in alpha 1-subunit protein accumulation and an increase in Na,K-ATPase transport activity. The half-life of alpha 1-mRNA analyzed by actinomycin D chase was less than 3 hours and was not affected by T3. Transfection experiments with the luciferase reporter gene revealed that thyroid hormone response sequences are located within the 5'-flanking regions of each alpha-isoform gene.(ABSTRACT TRUNCATED AT 250 WORDS)

The magnetic hyperfine splitting frequencies of123INi,124INi and131INi in a zero external magnetic field have been determined by the NMR-ON method as 258.9(1), 165.9(1) and 179.5(2) MHz, respectively. With the known values of the magnetic moments, the magnetic hyperfine fields have been deduced:BHF(123INi)=30.17(5) T,BHF(124INi)=30.14(9) T,BHF(131INi)=30.06(4) T; the weighted average isBHF(INi)=30.11(4) T. The small difference of theBHF(131INi) with those of123INi and124INi is discussed comparing with results of the hyperfine splitting frequency of iodine in iron host.

Microelectrode techniques were used to determine the Na+ and K+ transport properties of the collecting duct cell in the isolated cortical collecting duct (CCD) from rabbits 14 d after uninephrectomy (UNX); results were compared with those from sham-operated rabbits (control). UNX had no effects on plasma aldosterone levels. The CCDs from UNX rabbits exhibited structural hypertrophy. The lumen negative transepithelial voltage and the basolateral membrane voltage (VB) were elevated in the UNX group. Although the transepithelial conductance (GT) and the fractional apical membrane resistance (fRA) were not different between the two groups, the conductances of the apical and the basolateral membranes were increased, and the tight junction conductance was decreased in the UNX group. The amiloride-sensitive changes in apical membrane voltage (VA), fRA, and GT were greater in the UNX group. The changes in VA upon raising the perfusate K+ concentration and the changes in VA and GT upon addition of Ba2+ to the perfusate were elevated in the UNX group. Upon raising K+ in the bath, a large depolarization of VB was observed in the UNX group. Lowering the bath Cl- resulted in a small depolarization of VB in the UNX group. Addition of Ba2+ to the bath in the UNX group caused the VB to hyperpolarize in parallel with decreases in GT and fRA whereas in the control group it had no effect on VB. Addition of ouabain to the bath resulted in a large depolarization of VB in the UNX group. We conclude that (a) UNX stimulates conductances of Na+ and K+ in the apical membrane, active Na(+)-K+ pump activity, and K+ conductance in the basolateral membrane, independently of plasma aldosterone; (b) The basolateral membrane in the tubules of UNX rabbits is more selective to K+; and (c) the hyperpolarization of VB upon UNX may increase passive K+ entry into the cell across the basolateral membrane.

The nuclear magnetic moments of $^{124}\mathrm{I}$, $^{126}\mathrm{I}$, and $^{130}\mathrm{I}$ have been measured by the techniques of low-temperature nuclear orientation and nuclear magnetic resonance on oriented nuclei. The magnetic hyperfine splitting frequency \ensuremath{\Vert}g${\mathrm{\ensuremath{\mu}}}_{\mathit{N}}$${\mathit{B}}_{\mathrm{HF}}$/h\ensuremath{\Vert} for $^{124}\mathit{Fe}$ was determined to be 630.2(2) MHz from a field-shift analysis of the measured resonances at the external field of 0.1, 0.2, 0.4, 0.6, and 0.8 T. The resonances for $^{126}\mathit{Fe}$ and $^{130}\mathit{Fe}$ were observed in an external magnetic field of 0.2 T at \ensuremath{\nu}${(}^{126}$IFe)=627.7(2) MHz and \ensuremath{\nu}${(}^{130}$IFe)=585.7(2) MHz, respectively. Using the recalculated hyperfine field of ${\mathit{B}}_{\mathrm{HF}}$${(}^{131}$IFe)=114.50(5) T, the magnetic moments were deduced: \ensuremath{\Vert}\ensuremath{\mu}${(}^{124}$I,${2}^{\mathrm{\ensuremath{-}}}$)\ensuremath{\Vert}=1.444(4)${\mathrm{\ensuremath{\mu}}}_{\mathit{N}}$, \ensuremath{\Vert}\ensuremath{\mu}${(}^{126}$I,${2}^{\mathrm{\ensuremath{-}}}$)\ensuremath{\Vert}=1.436(5)${\mathrm{\ensuremath{\mu}}}_{\mathit{N}}$, and \ensuremath{\Vert}\ensuremath{\mu}${(}^{130}$I,${5}^{+}$)\ensuremath{\Vert}=3.349(7)${\mathrm{\ensuremath{\mu}}}_{\mathit{N}}$. The present value of the magnetic moment of $^{124}\mathrm{I}$ is very different from the value of 1.14(8)${\mathrm{\ensuremath{\mu}}}_{\mathit{N}}$ reported previously. The measured values of the magnetic moments are discussed using Land\'e formula.

To evaluate the relationship between renal cortical volume, measured by an automatic contouring software, with body mass index (BMI), age and renal function.The study was performed in accordance to the institutional guidelines at our hospital. Sixty-four patients (34 men, 30 women), aged 19 to 79 years had their CT scans for diagnosis or follow-up of hepatocellular carcinoma retrospectively examined by a computer workstation using a software that automatically contours the renal cortex and the renal parenchyma. Body mass index and estimated glomerular filtration rate (eGFR) were calculated based on data collected. Statistical analysis was done using the Student t-test, multiple regression analysis, and intraclass correlation coefficient (ICC).The ICC for total renal and renal cortical volumes were 0.98 and 0.99, respectively. Renal volume measurements yielded a mean cortical volume of 105.8cm(3)±28.4SD, mean total volume of 153cm(3)±39SD and mean medullary volume of 47.8cm(3)±19.5SD. The correlation between body weight/height/BMI and both total renal and cortical volumes presented r=0.6, 0.6 and 0.4, respectively, p0.05, while the correlation between renal cortex and age was r=-0.3, p0.05. eGFR showed correlation with renal cortical volume r=0.6, p0.05.This study demonstrated that renal cortical volume had a moderate positive relationship with BMI, moderate negative relationship with age, and a strong positive relationship with the renal function, and provided a new method to routinely produce volumetric assessment of the kidney.

The previously reported 330.8\ifmmode\pm\else\textpm\fi{}1.0-keV electron line in ${\mathit{e}}^{+}$+Th interactions has been reinvestigated to confirm its existence. We have made a definite observation of the relevant peak with an energy of 330.1\ifmmode\pm\else\textpm\fi{}0.3 keV, a fullwidth at half maximum of less than 1.7\ifmmode\pm\else\textpm\fi{}0.7 keV and a cross section of 160(1\ifmmode\pm\else\textpm\fi{}0.19\ifmmode\pm\else\textpm\fi{}0.25) mb. We have assigned the generation site of the electrons to the Th target by comparing the energy shift and the shape change of the line with those of the neighboring conversion lines in the spectra taken under different scattering conditions.

Nuclear magnetic resonances of oriented 137m,g Ce and 139 Ce in an iron host have been measured at 7 mK. From the resonance-shift measurement of 137m Ce, the magnetic hyperfine splitting frequency ν=|µ B HF / I h |, the magnetic moment µ and the magnetic hyperfine field B HF were derived as ν=54.25(1) MHz, \(|\mu(^{137\text{m}}\text{Ce}, \frac{11}{2}^{-})|=1.01(4)\mu_{\text{N}}\) and B HF ( 137 Ce Fe )=-38.8(10) T, respectively. The resonance frequencies of 137g Ce Fe and 139 Ce Fe at the external field of 0.2 T were found to be 188.3(5) and 208.5(5) MHz, respectively. With the measured hyperfine field, the magnetic moments of 137g Ce and 139 Ce were deduced as \(|\mu(^{137\text{g}}\text{Ce}, \frac{3}{2}^{+})|=0.96(4)\mu_{\text{N}}\) and \(|\mu(^{139}\text{Ce}, \frac{3}{2}^{+})|=1.06(4)\mu_{\text{N}}\). The measured magnetic moments are compared with the theoretical values based on the core-polarization model.

NMR-ON measurements have been performed for60CoFe−Si. The samples of Fe−Si (6 at. %) single crystal dish with the (110) surface were used. Rosonance measurements have been carried out with the magnetization direction along the and the axes. Five prominent resonances were found at 166, 162, 151, 147 and 135 Mllz. The resonance at 166 Mllz has been known to be due to60Co without neighbourt Si atoms. The resonances at 151 and 135 Mllz are due to60Co nuclei with one and two Si atom(s) in the 1st neighbour site, respectively. The resonances at 162 and 147 Mllz would be due to the contribution of the 3rd and the magnetization axes, the differences of the resonance width have been qualitatively explained using the dipolar field.

We demonstrated the cancellation of the external magnetic field by the nuclear field at one edge of the nuclear polarization bistability in single InAlAs quantum dots. The cancellation for the electron Zeeman splitting gives the precise value of the hole g-factor. By combining with the exciton g-factor that is obtained from the Zeeman splitting for linearly polarized excitation, the magnitude and sign of the electron and hole g-factors in the growth direction are evaluated., 3 pages, 2 figures

The tip artifact in atomic force microscopy (AFM) observations of InAs islands was evaluated quantitatively. The islands were grown in the Stranski-Krastanow mode of molecular beam epitaxy. The width and height of the islands were determined using transmission electron microscopy (TEM) and AFM. The average $[\bar{1}10]$ in-plane width and height determined using TEM excluding native oxide were 22 and 7 nm, respectively; those determined using AFM including the oxide were 35 and 8 nm, respectively. The difference in width was due to the oxide and the tip artifact. The sizes including the oxide were deduced from TEM observations to be a width of 27 nm and a height of 6 nm with correction for the thickness of the oxide. The residual difference of 8 nm between the width determined using AFM and that determined using TEM including the oxide was ascribed to the tip artifact. The results enable us to determine the actual size of the islands from their AFM images., 5 pages, 4 figures, 1 table, (C) 2007 American Institute of Physics

$\mathrm{In}\mathrm{As}∕\mathrm{Ga}\mathrm{As}$ quantum dots (QD's) are formed by postgrowth annealing of an InAs wetting layer thinner than the critical thickness for the transition from two- (2D) to three-dimensional (3D) growth mode. Reflection high energy electron diffraction is used to monitor the QD formation. Based on a mean-field theory [Phys. Rev. Lett. 79, 897 (1997)], the time evolution of total QD's volume, first increasing and finally saturating, is well explained by precursors forming during wetting layer growth and converting into nucleated QD's after growth stop. Both the saturation QD's volume and the QD nucleation rate depend exponentially on the InAs coverage. These behaviors and their temperature and InAs growth rate dependences are essentially understandable in the frame of the mean-field theory. Similar analysis to conventional QD growth suggests that the often observed significant mass transport from wetting layer to QD's can be ascribed to the precursors existing before 2D-3D growth mode transition.

Beam diagnostics: beam intensity monitors (DCCT SCT, FCT, WCM), beam position monitors (ESM), beam loss monitors (proportional chamber, air ion chamber), beam profile monitors (secondary electron emission, gas-sheet) have been designed, tested, and will be installed for the Main Ring synchrotron (MR) of J-PARC (Japan Proton Accelerator Research Complex). This paper covers the basic design principle and specification of each monitor of the MR and the beam transport line from 3 GeV rapid cycling synchrotron to the MR (3-50BT), with a stress on how to cope with high power beam (average circulation current of ∼13 A) and low beam loss operation (less than 0.5 W/m except a collimator, injection and extraction region). Some results of preliminary performance test using present beams and a radiation source will be reported.

A pulse height analysis technique for observing X-rays is planned for Large Helical Device (LHD) plasma experiments to estimate electron temperature and the amount of impurities. The estimation of the nonthermal electrons heated by electron cyclotron heating is also expected. In addition to these primary interests, X-ray observations will be made with a space resolution of better than 10 mm in the radial direction in order to investigate attractive local phenomena occurring in the plasma.

This chapter introduces the overall coal-seam CO 2 -sequestration project and presents the results of the laboratory analyses, well-logging, and water-injection falloff tests conducted to date. The data are used to predict the likely results of the future CO 2 huff-and-puff and multi-well tests. The CO 2 -sequestration project entitled “technology development for carbon dioxide sequestration in coal seams” started with a purpose to develop a series of processes that can extract the CO 2 discharged from thermal power plants and other large-scale emitters of CO 2 , and fix it in coal seams in a stable form while recovering methane as a clean energy source. It has introduced the coal-seam CO 2 -sequestration project and presented analytical results for the Y10 coal seam in the Ishikari coal field based on laboratory experiments, well-logging, and water-injection falloff tests. The expected results of future CO 2 huff-and-puff tests and multi-well test have been simulated based on these analyses in order to aid the field-test design. From the simulations, it is estimated that the initial coalbed methane gas production rate is likely to be almost 500 m3/day and that this rate will increase by a factor of two or three once CO 2 is injected due to CH 4 /CO 2 exchange within the coal seam. The adsorbed CO 2 volume is estimated to be 72% of the injected CO 2 for the huff-and-puff field test, and 96% for the multi-well test.

We propose a new functional optical-electrical switching device: a multi-emitter heterojunction photo-transistor (ME-HPT) using a multi-emitter heterojunction bipolar transistor (ME-HBT) structure. In this device, the collector current (I/sub C/) can be controlled by not only the incident radiant power (P/sub 0/) but also the voltage difference between emitters (V/sub EE/). We fabricated ME-HPT's using InGaAs/InP heterostructures and confirmed the normal operation. Using only one ME-HPT, we have successfully demonstrated a new functional optical-electrical switching operation, which can switch on only when both the electrical and optical signals are high. >

Simple POF-type humidity sensor using a combination of swelling polymers, which is based on the structure change from leaky-POF to guided-one, was confirmed to operate over the wide humidity range and to be used as a breathing-condition monitor.

A technique for the regenerative control of a voltage source inverter is described. In the proposed equipment, the rectifier bridge is utilized for regeneration through a medium of a DC reactor. Another type of regenerative control that involves a modified Cuk converter method is described. A frequency analysis approach using the switching function is used in order to analyze the output current waveforms. The appropriateness of this theory is experimentally confirmed. >

Several functional dye-doped plastic fibers have been fabricated and used for optical applications. Laser-dye-doped plastic fibers pumped by a pulsed N/sub 2/ laser operate as a compact tunable fiber laser with an intense and narrowed spectrum over a wide wavelength range. A halogen-lamp-illuminated fluorescent plastic fiber can be used for a simple fiber light source. The combination of plastic fiber doped with thymol-blue dye and the fiber light source operates as an optical sensor for toxic gases such as NH/sub 3/ and HCl. A humidity sensor using a dye-doped plastic fiber was also fabricated. >

In planning a distribution system, when feeders are newly installed, several tie lines to other feeders must be determined among many candidates, considering investment cost and constraints. However, it is difficult for planners to find the optimal tie line set, because too many candidates exist which can be constructed along the road on service area of the power company. In this paper, in order to support the planners' decision for selecting an optimal tie line of newly installed feeders, the authors have formulated the problem mathematically, and propose a new solution algorithm by using Tabu Search to find superior tie lines. Through numerical examples, the authors demonstrate the validity of the proposed method.

In order to forecast demand precisely through a year, we should consider various types of days. This paper presents a peak load forecasting method for special periods. In Japan, there are three special periods whose peak loads are usually less than normal days' loads. These peak loads are influenced by annual variation, date and day of the week. These facts request a new method that is different from the forecasting methods for normal days. A proposed method detects order relations of labelled days in the special period based on the days' peak loads. A labelled day is a date labelled day of the week, such as January 1st (Sun) or a date labelled abstracted day of the week, such as January 1st (weekday). The proposed method refines order relations by changing labels from detailed levels to abstracted levels. Final order relations show a structure among labelled days in the special period on peak loads. By using results of final order relations, a peak load of each day in the special period is predicted. Performance of the method which is verified with simulations on actual load data of Tokyo Electric Power Company (TEPCO) is also described.

Defects generated in GaAs/InAs three-dimensional layer/GaAs heterostructures grown on [001]GaAs substrates by molecular beam epitaxy have been systematically evaluated by transmission electron microscopy. The crystal growth of InAs on GaAs is subject to Stranski-Krastanow mode, that is, two-dimensional growth up to 1 monolayer coverage, then three dimensional growth. During the growth of 1 to 2.5 monolayers of InAs, the density of islands linearly increases with growth coverage while their diameter remains constant. When the coverage of InAs exceeds 2.5 monolayers, large islands are often formed by coalescence of two islands. Three types of defects are observed: V-shaped dislocations consisting of two dissociated dislocation pairs, multiple intrinsic stacking faults lying on one to four equivalent {III}planes and dislocation loops. All of these defects originate from the large islands. Based on a detailed characterization of these defects, possible generation mechanisms are discussed.