Improved Yen-Joye's authenticated multiple-key agreement protocol

An authenticated multiple-key agreement protocol is proposed. The protocol is not only secure against the unknown-key attack but also more efficient than other protocols.     

The lattice dynamics of the Fe(tpa) (NCS)2 complex : light-induced excited spin state trapping effect

A light-induced excited spin state trapping (LIESST) experiment for a thermal gradual spin crossover complex, Fetris (2-pyridylmethyl) amine(NCS)2 or Fe(tpa) (NCS)2, was attempted for the first time. The high spin (HS) state after light inducement stayed metastable over a period of days without relaxation at 10 K. Intersystem relaxation from a high to a low spin (LS) complex occurred at 50 K after bleaching at 10 K. Investigation of the Mossbauer spectra of the LIESST and relaxation experiment indicated that the Debye–Waller factor was a correlation parameter of the HS fraction and that the co-operative effect played a role in the relaxation process for such a solid compound. This revised version was published online in November 2006 with corrections to the Cover Date.     

Neural network impedance force control of robot manipulator

The performance of an impedance controller for robot force tracking is affected by the uncertainties in both the robot dynamic model and environment stiffness. The purpose of this paper is to improve the controller robustness by applying the neural network (NN) technique to compensate for the uncertainties in the robot model. NN control techniques are applied to two impedance control methods: torque-based and position-based impedance control, which are distinguished by the way of the impedance functions being implemented. A novel error signal is proposed for the NN training. In addition, a trajectory modification algorithm is developed to determine the reference trajectory when the environment stiffness is unknown. The robustness analysis of this algorithm to force sensor noise and inaccurate environment position measurement is also presented. The performances of the two NN impedance control schemes are compared by computer simulations. Simulation results based on a three-degrees-of-freedom robot show that highly robust position/force tracking can be achieved in the presence of large uncertainties and force sensor noise     

Air bearing design, optimization, stability analysis andverification for sub-25 nm flying

Three sub-25 nm fly height sliders are presented for near contact recording. The designs are geared towards the goal of achieving 10 Gb/in ² areal density. The optimization procedure presented shows promise for facilitating achievement of this goal. The dynamic simulations show the stability of these designs when disturbed from their steady state conditions     

A new technique for robust control of servo systems

The robust controller has very simple structures and can be divided into two separate parts: a servo controller and an auxiliary controller. The two controllers are designed independently. The function of the auxiliary controller is to cancel out the plant uncertainties directly without the use of the high loop gain principle. Interpretation of robot controller as a signal-synthesis adaptive controller is given. Practical implementation issues of the auxiliary controller are discussed. Simulations of a design example with large parameter uncertainty, nonlinearity, and external disturbance are presented to demonstrate the effectiveness of the design technique. This technique is further tested with success in an experimental study of joint position control of a PUMA 560 robot arm     

Shift-Register-Based Data Transposition for Cost-Effective Discrete Cosine Transform

This paper presents a cost-effective 2-D-discrete cosine transform (DCT) architecture based on the fast row/column decomposition algorithm. We propose a new schedule for 2-D-DCT computing to reduce the hardware cost. With this approach, the transposed memory can be simplified using shift-registers for the data transposition between two 1-D-DCT units. A special shift cell with MOS circuit is designed by using the energy transferring methodology. The memory size can be greatly reduced, and the address generator and its READ/WRITE control all can be saved. For an 8 times 8-block transformation, the number of transistors is only 4 k for the shift-register array. The maximum frequency of shift-operation can achieve about 120 MHz, when implemented by 0.35-mum technology.     

A novel integration approach for combining the components to minimize a micro-fuel cell

This work employs porous silicon as a gas diffusion layer (GDL) in a micro-fuel cell. Pt catalyst is deposited on the surface of, and inside, the porous silicon by the physical vapor deposition (PVD) method, to improve the porous silicon conductivity. Porous silicon with Pt catalyst replaces traditional GDL, and the Pt metal that remains on the rib is used to form a micro-thermal sensor in a single lithographic process.     

Effects of the International Temperature Scale of 1990 (ITS-90) on CIE Documentary Standards for Radiometry,Photometry, and Colorimetry

The differences between ITS-90 and IPTS-68 above 1235 K are described. It is shown that none of the following CIE definitions or recommendations require revision because of the introduction of the ITS-90: International Lighting Vocabulary definitions; CIE Standard Illuminants A, D₆₅, other illuminants; and sources for realizing CIE Illuminants. The effect of the ITS-90 on previously calibrated sources for realizing CIE illuminants is negligibly small.²