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Accumulative roll bonding (ARB) is a kind of severe plastic deformation process which can produce high strength metals with ultra-fine grained microstructure. Mechanical properties will be increased due to the ultra-fine grain structures. In this study, the ARB process is used, the snap–stack working to reduplicate Al (ASM-1100)/Mg (AZ31) alloy which is chosen and then made thinner and longer by rolling and repeating the processes. Steps of 12 layers are created. The ARB process creates a multilayer compound between Al/Mg layers with excellent bonding characteristics and fine grained microstructure. The bonding condition became ascendant gradually and increased from one to three cycles. The grain sizes of Al and Mg alloys were 875 nm and 656 nm after three cycles. The hardness of the Al and Mg alloys were raised to HV42 and HV90 after three cycles.

Threshold current and quantum efficiency of the surface-emitting laser diodes were calculated on the basis of a planar carrier diffusion model with cylindrical boundary and analytical electromagnetic field distribution in either a uniform core waveguide or Vainshtein's open cavity model. Surface recombination at the boundary of the quantum-well active region was much greater than the bulk recombination in both structures unless cavity diameter was greater than 50 /spl mu/m. Diffraction loss was also significant in the open cavity structure as cavity diameter decreased. Reducing the surface recombination velocity leads to the reduction of threshold current and enhancement of differential quantum efficiency. In order to further reduce that current, using a buried heterostructure with a vertical waveguide structure is suggested.

Based on the open resonator theory, a model of a complex coupling coefficient suitable for the analysis of an ultrashort external-cavity laser diode is presented. It is shown that the effective reflectivity of the short external-cavity laser diode calculated by using this model is a function of the size of the laser-emitting area and is significantly influenced by the phase-modification factor as well as by the amplitude-reduction factor of the complex coupling coefficient. The calculated output power characteristics show good qualitative agreement with experimental observation. The necessary condition that the optical disk head using an external-cavity laser diode does not fail to detect the recorded signal for a broad range of flying height is also derived. >

Many resonances in the reaction {sup 27}Al+{ital p} for {ital E}{sub {ital p}}=3.58--4.06 MeV were observed corresponding to excitation energies {ital E}{sub {ital x}}=15.03--15.50 MeV of the compound system {sup 28}Si. We measured the excitation functions for the decay mode with exit channels ({ital p}{sub 0--}{ital p4},{alpha}{sub 0},{alpha}{sub 1},{gamma}) in the above proton energy range with energy steps of 2 keV at 135{degree} and 145{degree} for proton and {alpha} particles and at 60{degree} for gamma rays. Two solid-state detectors and a 5.1 cm{times}5.1 cm NaI(Tl) scintillator were employed. High experimental resolution of {similar to}1 keV enables us to deduce the average {sup 28}Si level spacing in the region of 15 MeV excitation. The structure of resonances is discussed and energies, together with widths of resonances, are presented. The {ital J}{sup {pi}} assignment for several resonances was proposed as well.

A highly scaled, high performance 45 nm CMOS technology utilizing extensive immersion lithography to achieve the industry's highest scaling factor with ELK (k=2.55) BEOL is presented. A record gate density 2.4X higher than that of 65 nm is achieved. Refined strained-CMOS demonstrated 1200/750 μA/μm Idsat at 100 nA/μm Ioff, Vdd=1 V, which has the best Ion-Lg performance reported for bulk CMOS device. The proposed 45 nm technology is not only manufacturing friendly but also has well-controlled leakage and mismatch evidenced by a functional 32 Mb 0.242 μm2 SRAM.

It is now well recognized that the Byzantine Agreement (BA) problem is a fundamental problem in implementing fault-tolerant distributed services. Traditionally, the BA problem is solved in the fully connected network or in the broadcast network. In this paper, BA problem is reexamined under the mobile network. The proposed protocol Byzantine Agreement under Mobile Network (BAMN) uses the minimum number of message exchanges to reach an agreement while tolerating the maximum number of faulty processors in the distributed system. It makes all the fault-free processors reach a common value to keep the system from the influences of processor failures.

This paper describes a leading-edge 0.18 /spl mu/m CMOS logic foundry technology. Very aggressive design rules and borderless contacts render a 4.4 /spl mu/m/sup 2/ embedded (synchronous cache) 6T SRAM cell demonstrated in a 1 Mb vehicle with very high yield. Robust dual-gate oxides were developed to support 1.5-2 V core logic as well as 3.3 V periphery (I/O) circuitry. Advanced modular core device technology using 32 /spl Aring/ oxides for 1.8-2 V operation and 27 /spl Aring/ oxides for 1.5-1.7 V applications support competitive high-performance (MPU/graphics) or low-standby power (mobile) applications. Transient-enhanced diffusion is effectively used in I/O devices to enhance hot-carrier lifetime. This is the first 0.18 /spl mu/m technology demonstrating a highly manufacturable 6 to 7 level low-k (HSQ)/AlCu interconnect system with tightest metal pitch (0.46 /spl mu/m M1 and 0.56 /spl mu/m at intermediate levels), as well as aggressive borderless and fully stacked vias without poisoning problems. AlCu/FSG and dual-damascene Cu/oxide interconnect options have also been proven with comparable SRAM yield to the AlCu/HSQ system.

Summary form only given. A multiple-Vt high performance, high density and highly manufacturable 0.25 /spl mu/m CMOS technology with a shallow trench isolation process has been successfully developed. Five metal layers with oxide CMP planarization, etchback W plug for borderless contacts/vias, and fully stacked contact/vias were used. Dual gate oxide process (5 nm for 2.5 V core, and 7 nm for 3.3 V I/O or 13 nm for 5 V I/O) with low defect density, and low Vt (/spl sim/0.2 V) or native Vt (/spl sim/0 V) devices for low power and mixed-mode applications are all demonstrated in this technology.

A leading-edge 0.13 /spl mu/m CMOS technology using 193 nm lithography and Cu/low-k interconnect is described in this paper. High performance 80 nm core devices use 17 /spl Aring/ nitrided oxide for 1.0-1.2 V operation. These devices deliver unloaded 8.5 ps gate delay @1.2 V. This technology also supports general ASIC applications with 20 /spl Aring/ oxide for 1.2-1.5 V operation and low-standby power applications with 26 /spl Aring/ for 1.5 V operation, respectively. Dual gate oxides of 50 or 65 /spl Aring/ are also supported for 2.5 V or 3.3 V I/O circuits respectively. Cu with low-k dielectric is used for the 8-layer metal interconnect system with tight pitch. The aggressive design rules and border-less contacts/vias support a high density 1P3M 2.43 /spl mu/m/sup 2/ 6T-SRAM cell without local interconnect. A suite of embedded SRAM cells (6T, 8T) with competitive density and performance optimized for different applications are also supported with memory compilers and large block macros.

This paper describes a leading-edge 0.15 /spl mu/m CMOS logic foundry technology family. Advanced core devices using 20 /spl Aring/ oxides for 1.2-1.5 V operation (L/sub G min/=0.1 /spl mu/m) support high-performance CPU and graphics applications. The technology supports also low-standby power applications with 26 /spl Aring/ oxide for 1.5 V operation. Periphery circuitry for 2.5 or 3.3 V compatibility use dual 50 or 65 /spl Aring/ gate oxides respectively. AlCu with low-k (FSG) is used for the seven-level metal interconnect system with extremely tight pitch (0.39 /spl mu/m for M1 and 0.48 /spl mu/m for intermediate levels). The aggressive design rules and border-less contacts/vias render an embedded (synchronous cache) 6T SRAM cell of 3.42 /spl mu/m/sup 2/ demonstrated in a 2Mb vehicle with very high yield. The overall process reliability is also shown to meet standard industry requirements.

Asymmetry in optical power versus external-cavity length characteristics has been observed in a short-external-cavity laser-diode configuration. It is shown that this phenomenon can be explained only by introducing a complex coupling coefficient, representing the coupled field amplitude into the laser diode at each reflection. This supports the open resonator model description of the short-external-cavity laser diode. Such an asymmetry effect should be recognized and properly dealt with in any laser-diode sensor. >

Under a high-gain operating condition, the presence of a multiplication process in the InGaAs(P) regions of an InP/InGaAsP/InGaAs avalanche photodiode (APD) having a structure of separated absorption and multiplication regions could lead to significant enhancement of the avalanche buildup time. As a result, the bandwidth of the device could be reduced considerably. The dependence of the avalanche multiplication factor and the intrinsic response time on the reverse bias voltage, the heterointerface field, the doping concentrations, and the width of the InP layer is examined in detail for the case in which hole injection is assumed. It is shown, for example, that for a fixed value of doping concentrations, reduction of the excess noise factor and enhancement of the gain-bandwidth product of the device can be achieved at the same time by a proper increase of the width of the InP layer. >

Polymer membranes, slabs, etc. can be effectively protected in time against permeation by an environmental polluting agent by self-regenerating, thin surface films of suitable film-forming materials initially dispersed in small amounts (less than 5 weight percent) in the polymer. These thin surface films (about 0.5 micrometers) can be either chemically passive to the polluting agent or be designed to react or catalyze a reaction with the agent in the presence of atmospheric oxygen or water vapor. We have studied the effectiveness of a number of passive film formers and a reactive film former in protecting a polyurethane elastomer, polyvinyl chloride and polyethylene towards a model polluting agent, tributyl phosphate. The presence on the polymer surface of the film former and its regeneration (within minutes) on scratching was followed by advancing contact angles of water, optical microscopy and scanning electron microscopy. Permeation weight loss of the polluting agent in a modified cup apparatus yielded both steady state permeation fluxes and the Barrer—Daynes time lags. In all cases the film-protected polymers exhibited smaller steady state fluxes and longer time lags than control polymers without the surface film. The decrease due to the presence of the surface film of the effective permeability and diffusion coefficient was sufficiently large to make this a promising method of protection.

An effective method of two-dimensional transient analysis of potential and charge carrier distribution in a buried-channel charge-coupled device (BCCD) operating in storage and transfer modes has been developed with the aid of the finite Fourier transform (FET) technique. The effect of different clocking schemes on charge carrier transfer inefficiency and charge handling capacity are examined and discussed using the method developed. It is also shown that, for a BCCD operating in the storage mode, two-dimensional analysis indicates that the charge handling capacity determined by one-dimensional analysis can result in overestimation, which is misleading.

Assuming that the temperature dependence of the threshold current for pulsed operation is known, an analytical expression for the maximum heat-sink temperature, T/sub hm/, for CW operation of the laser can be derived. The maximum heat-sink temperature is expressed in terms of the characteristic temperature T/sub 0/, the room-temperature threshold current for pulsed operation I/sub 0/, the equivalent effective thermal resistance theta , and the equivalent effective series electrical resistance r of the device. It is shown that the values of T/sub hm/ can be enhanced by increasing the value of T/sub 0/ or by decreasing the values of I/sub 0/, theta , and r. >

Human dialyzable leukocyte extract (10(7) - 10(8) leukocyte equivalents, containing transfer factor) was administered intraperitoneally to CFW mice the day of and 2 days after intravenous infection with Candida albicans. Tissue Candida populations were determined immediately after and 2, 4, 7 and 14 days after infection. Kidney populations were significantly reduced on 27% of the days studied. Similar reduction in C. albicans census was obtained after injection of leukocyte extracts from donors skin test-positive to Candida antigens or donors negative to Candida antigens by skin test and migration inhibition analyses. There was no evidence of a dose-response relationship for leukocyte extract in the range 10(5) - 10(9) leukocyte equivalents. When mice were primed with C. albicans antigen 4 weeks prior to challenge the efficacy of leukocyte extracts was not augmented. There was no evidence that the infection-reducing effects were related to augmented polymorphonuclear leukocyte mobilization, increased mononuclear clearance of C. albicans, or to a direct toxic effect on C. albicans blastospores. These studies suggest that the reduction in Candida populations was non-specific and give further impetus to the use of the dialyzable leukocyte extracts as non-specific supplements to antibiotics in overwhelming or recalcitrant infections in man.

This paper considers the synthesis of a final value system by using the theory of eigenfunctions and the gradient methods. The applicability of these two approaches is explored, and it is shown that the final value problems treated in this paper always include the minimum effort problems. The concept of “Adjoint Space Approach” to the solution of the problems will be introduced. By using this approach, a great reduction in the dimensionality of the problems can be achieved.

The first part of this paper gives a general approach to the least squares estimation of the weighting function matrix of a linear multivariable system by using normal operating records. It will be shown that a great reduction in the dimensionality of the problem can be achieved by first obtaining a solution in the adjoint space. The estimated weighting function matrix can then be determined simply by operating on it with an adjoint operator. When the identification procedure is used on-line with the system operation, two recursive schemes are devised to up-date the estimation to incorporate adding new data and deleting old data. Finally, the identification of a nonlinear system which can be represented by a power series expansion for a continuous functional established by Frechet will be discussed. A steepest descent method in the Hilbert space and its modified version are introduced as a practical means for solving this estimation problem.

New approximations for the carrier generation rates in silicon under AM1 and AM2 solar illumination are presented. They may simplify the analysis of silicon solar cells, particularly when done by hand.

Publisher Summary An adaptive control system must be able to perform the following three functions: provide continuous information about the present state of the system or identify the system; compare present system performance to the desired or optimum performance and make a decision as to how the system should be guided to achieve the optimum performance; and, finally, initiate a proper actuation so as to drive the control system to the optimum. These three principles of identification, decision, and actuation are inherent in any adaptive system. The advance of adaptive control theory is a natural evolution of the control technology. The impact on its development has many facets. Control engineers were confronted with problems in which the classical control techniques developed previously were proving very inadequate. This chapter highlights the problems associated with adaptive control systems. It describes one possible approach for solving adaptive control problems. These problems are formulated within the context of functional analysis. All the problems with least-squares criteria are basically identical with the operator-theoretic formulation. They can all be rewritten as the minimization of certain norms in specifically defined Hilbert spaces. This function-space approach for solving a class of control problems has been used extensively. The chapter discusses the interpretation of the well-known, generalized, least-squares error criterion as the minimization of a quadratic functional in Hilbert space. It also discusses minimum effort problems. The chapter discusses the least-squares estimation of a linear system weighting function matrix, the identification problem of a nonlinear system, and the optimal control of nonlinear systems.

The multivariable nonlinear system considered here is assumed to be characterized by a truncated functional power series. The system is to be identified under normal operating conditions. Least square error criterion is used to estimate the system weighting function matrix and a steepest descent method is employed for solving this problem. A recursive estimation scheme is devised for up-dating its estimation. An “Adjoint Space Approach”, which has the advartage of reducing the dimensionality of the identification problem is explored.