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Silicon-based devices, including the increasingly available SiGe-based devices, are now demonstrating f_T and f_MAX values over 200 GHz. These recent advances open the door to a wide range of silicon-based very high frequency, low power and highly integrated solutions. Trends in silicon MOS, SiGe HBT, SiGe MODFET and SiGe strained silicon FETs are reported. Silicon inroads to device functions viewed as the sole realm of III-V technologies are also being demonstrated. Capability and trends of the integrated silicon photodiode are reported here as an example. Integration of these high-speed devices into a complex circuit requires on-chip passive device functionality at such high frequency. Key devices to enable integration are the inductor, varactor, and transmission line, and operation of these devices at high frequency is reported. Further, we discuss noise isolation issues and techniques, which may be used when minimizing cross-talk within a conductive silicon substrate.

The concept of Qi and the concept of channel are so closely related that they must be defined and comprehended simultaneously in a coordinated fashion. Once the nature of Qi is established in terms of physics, we may be able to explain the functional role that the channels play, as well as explain other Chinese medical terminology with a language of modern science. Based on the low electrical impedance characteristics of acupoints, we propose that the meridian channel is equivalent to an electromagnetic transmission line and the Qi is the electromagnetic (EM) standing wave riding on the line, with acupoints as its nodes. The standing wave within each segment of the channel separated by acupoints is in natural oscillation thus the segment may be analyzed as a λ/4 open circuit that behaves like a series RLC resonator. Acupuncture until De Qi is effectively equivalent to charging the capacitor C_eq of the RLC resonator in the transmission line. The mechanism of bu and xie are charging or discharging the capacitor to bring the capacititive (or inductive) behavior of the segment back to that of the resonant state. Kirlian photograph may serve as a visual observation of the EM waves on channels.

Based on the electromagnetic model of the transmission line for the channel and the birdcage resonator for the meridian network, we interpret two effects, seemingly incomprehensible in terms of current Western physiology, the lasting effect and the remote effect. For the lasting effect, acupuncture enhances the amplitude of the Qi standing wave, and this increased amplitude is retained and thus is able to sustain a gradual remodeling of the extracellular matrix in interstitial connective tissues, resulting in a lasting therapeutic effect. For the remote effect (acupuncture effect far from the site of needle insertion), our model puts the mechanism of magnetic therapy on an equal footing with that of acupuncture. It may not be a coincidence that accounts of investigators in both acupuncture and magnetotherapy about the depth of the effective site — along cleavage planes between muscles, or between muscle and bone or tendon — are in accord with that of the Huang Di Nei Jing about the course of channels: "they are embedded and travel between interstitial muscles, deep and invisible." A possible magnetic field generated outside the birdcage may be manipulated to produce local areas of higher temperature or very strong fields.

It is imperative to define the fundamental concepts of Qi, channels, and the meridian system of Chinese medicine in terms of scientific terminology before any meaningful and mutually beneficial dialog can begin between Chinese and Western medicine. In the Chinese theory, the meridian system as a whole is the system of the body. We propose the existence of a meridian regulatory system that governs interactions between and adjusts functions of internal organs, connects them to the body surface through a network of pathways (channels) and displays their status on the skin. The meridian systems is analyzed as a 28-leg, uniform, low pass birdcage coil, where each leg represents a channel. The channel is analyzed as a transmission line and Qi is the standing wave riding on it. Each segment in the channel is represented as a section of the transmission line and it is in natural oscillation, with its second lowest resonant frequency being the 50-round circulation frequency f₅₀, 0.578 × 10^-3Hz.

This paper considers the noise modeling of interconnections in on-chip communication. We present an approach to illustrate modeling and simulation of interconnections on chip microsystems that consist of electrical circuits connected to subsystems described by partial differential equations, which are solved independently. A model for energy dissipation in RLC mode is proposed for the switching current/voltage of such on-chip interconnections.

The Waveform Relaxation (WR) algorithm is presented in this paper to address limiting in simulating NoCs due to the large number of coupled lines.

We describe our approach to the modeling of on-chip interconnections. We present an applicative example of our approach with VHDL-AMS implementations and simulation results. This article analyzes the coupling noise, the bit error rate (BER) as well as the noise as a function of the rise/fall time of the signal source which can significantly limit the scalability of the NoCs.

The paper presents a computationally efficient method for modeling and simulating distributed systems with lossy transmission line (TL) including multiconductor ones, by a less conventional method. The method is devised based on 1D and 2D Laplace transforms, which facilitates the possibility of incorporating fractional-order elements and frequency-dependent parameters. This process is made possible due to the development of effective numerical inverse Laplace transforms (NILTs) of one and two variables, 1D NILT and 2D NILT. In the paper, it is shown that in high frequency operating systems, the frequency dependencies of the system ought to be included in the model. Additionally, it is shown that incorporating fractional-order elements in the modeling of the distributed parameter systems compensates for losses along the wires, provides higher degrees of flexibility for optimization and produces more accurate and authentic modelling of such systems. The simulations are performed in the Matlab environment and are effectively algorithmized.

In this paper the models of the transmission line with one DOF, two DOFs and three DOFs are constructed respectively by using Hamilton principle, where the initial location, the geometric nonlinearity caused by deformation and the aerodynamic nonlinearity caused by flow are considered. These simple models are accurate and can be used for the theoretical analysis. In actual engineering, the critical wind speed of galloping has been paid more and more attention. Therefore, in this paper the critical wind speeds are obtained by Lyapunov stability theory and the effects of structural parameters to the critical wind speed are discussed for different models. And the response curves of the system with one DOF and two DOFs (out-of-plane motion) are obtained by using harmonic balance method and multiple scale method, respectively. The bifurcation of the system moving out-of-plane is analyzed by singularity theory. For the systems whose motion is coupled with torsion, the numerical results are given by using the fourth order Runge–Kutta method. Additionally, the effects of the dynamic vibration absorber and detuning pendulum to the anti-galloping of the transmission line are studied for different cases.

The ice shedding may cause the vibration of conductors, and even threaten the safety of towers in severe cases. Based on two test models with a single span and three spans, an advanced three-dimensional motion capture system, the NDI Optotrak Certus System, is used to measure the dynamic response of the conductor following ice shedding. The influences of the ice thickness, ice-shedding ratio, ice-shedding location, and sequence are investigated. The results show that the ice-shedding velocity significantly impacts the dynamic response of conductors, and a larger ice-shedding velocity leads to a smaller jump height. The conclusions drawn from the model tests can guide the deicing and design of power lines.

In this paper we analyze the properties of a chain of forward-coupled bi-stable over-damped oscillators. It is well known that this system displays stochastic resonance and behaves as a transmission line when an adequate amount of noise is added to each oscillator, and the first oscillator is driven by a periodic (sine) modulating signal. By driving the first oscillator with a modulated sequence of random non-return-to-zero (NRZ) bits, we start by showing that the system exhibits a stochastic-resonance behavior. Then we show that bit delays can be adjusted by either changing the amount of noise and/or the coupling intensity between adjacent oscillators. We find that the system can be regarded as a tunable delay line for a broad range of noise and coupling parameters, a feature that may find applications in information processing and bit regeneration.

In order to further understand the generation mechanism of Heart Sound, we introduce a new method for simulating Heart Sound by using cascaded and lossless acoustic tubes. Based on the theory of acoustics, we abstract the ventricles and arteries inside of the heart as multistage tubes with equal length and different radii. By controlling the radii of tubes, we simulate the process of relaxation and constriction of the ventricles and arteries. Then, we calculate the transfer function of the tubes based on the theory of reflective transmission line. To gain the tubes’ radii, we use formant frequency as the model target parameters and put forward an approximation method. Finally, the experimental results show that compared with traditional model, the model based on cascaded and lossless acoustic tubes could better reflect the state of the ventricles and arteries. Meanwhile, by comparing the model tube radius of normal Heart Sound and pathological Heart Sound, we can give a better explanation to the cause of pathological Heart Sound.

A study of multimodal galloping is carried out on an iced transmission line with thin ice accretions. The partial differential governing equations of iced transmission line are established to describe the nonlinear interactions between the in-plane, out-of-plane and torsional vibration, in which geometrical and aerodynamic nonlinearities are considered. The transformation of modal galloping with the continuous variations of parameters and modal interactions are analyzed based on the reduced model obtained by employing Galerkin spatial discretization. Eigenvalue analysis is applied on linear system to determine the switch of different modal galloping in plane U -l, where Hopf bifurcation occurs and mono-modal, bi-modal and multi-modal galloping are observed. Various numerical procedures are implemented to capture the outstanding nonlinear dynamic features of every regional galloping in plane U -l. Internal resonance is observed and investigated to interpret the phenomenon of modal transition which is also analyzed by accounting for the influence of initial conditions on galloping with either symmetric or anti-symmetric modes.

The planning, scheduling and operation decisions of the power grid depend on the calculation of the simulation model. Parameter errors in the grid model can lead to deviations between simulation calculations and actual grid operation. The strategy based on incorrect calculation data will lead to power outages in the actual power grid, which may cause significant economic losses and personal safety accidents. For the safe operation of power grid, a method for locating the wrong parameters of transmission line based on sensitivity analysis (SA) and deep residual network (DRN) is proposed. By calculating the sensitivity of apparent power to parameter error of each line in the power grid, the propagation characteristics of power flow error are analyzed quantitatively. An error region segmentation method is proposed to reduce the search range of error parameters from large-scale power grids to local networks which can reduce the computational complexity of the search algorithm, and increase accuracy. An error transmission line index for local power grids is proposed to identify error source in local power grids. Then, the specific wrong parameters are identified through the DRN. It can intelligently identify the error parameters from multiple parameters of the error transmission line. The calculation results of the 300-bus system verify the correctness and effectiveness of the proposed method.

Silicon-based devices, including the increasingly available SiGe-based devices, are now demonstrating f_T and f_MAX values over 200 GHz. These recent advances open the door to a wide range of silicon-based very high frequency, low power and highly integrated solutions. Trends in silicon MOS, SiGe HBT, SiGe MODFET and SiGe strained silicon FETs are reported. Silicon inroads to device functions viewed as the sole realm of III-V technologies are also being demonstrated. Capability and trends of the integrated silicon photodiode are reported here as an example. Integration of these high-speed devices into a complex circuit requires on-chip passive device functionality at such high frequency. Key devices to enable integration are the inductor, varactor, and transmission line, and operation of these devices at high frequency is reported. Further, we discuss noise isolation issues and techniques, which may be used when minimizing cross-talk within a conductive silicon substrate.

The electrical energy transportation is influenced by fault of transmission lines. So the on-line detection of transmission lines faults is necessary requirement for the future development of power grid. This paper proposes an On-line fault detection method of transmission line based on the wavelet transforms theory. Firstly the analysis for signal singularity lee index of wavelet transform is given. Then a wavelet transform algorithm for fault detection is proposed. Finally Matlab simulation results show the effectiveness of the detection algorithm.

For the need of anti-wind and anti-vibration in transmission line construction and maintenance work, the design of anti-galloping fitting based on PID automatic controlling theory was introduced in this paper. Performance of this PID closed loop adjustment control was revealed as simulation results in the computer-aided software. Receiving displacement in the line from sensors in line as input signal, PID controller would compare the dynamic displacement and static one, and give position signal to the motor. Two kinds of the anti-galloping fitting had been introduced in this paper, which could make the PID principles described earlier more practical and trusted.

With the development of power grid construction, the frequency and intensity of transmission line galloping increased significantly, and transmission line galloping has become one of the most main factors threaten the security of power grid. Now, the monitoring technique for transmission line galloping is not mature, and has many defects and problems. A new method based on monocular vision technique is proposed in this paper. The results of on-site test have shown that the proposed method is feasible and effective.

Two slipping faults on connectors of aluminum tube rigid jumper in ±800kV Fu-Feng transmission line occurred continuously in 2011, which seriously threatened safe and stable operation of line. Many bolts in connectors loosed to various extent after inspection along the lines, so it was necessary to eliminate the inherent defects of aluminum tube connection on structure design. Basing on the structural characteristics and mechanical calculation of the aluminum tube jumper, the reasons of the faults are deeply analyzed form the structure design, manufacture, construction technology and operating conditions and so on. The measures to eliminate the defects by adding bolts were proposed on basis of field condition, also they were verified by experiments. Test results showed that the adding bolts can effectively prevent slip of the connector. The measures are simple and easy to implement in field, which can instruct implementation at site. The jumpers had operated steadily for three years after eliminating all the latent defects along the lines, and during that three full load tests were performed respectively. It proved that the defects were eliminated fundamentally, which ensured the safe and stable operation for a long time.

Autonomous obstacle avoidance of unmanned aerial vehicle (hereinafter referred to as UAV) in electric power line inspection process has important significance for operation safety and economy for UAV intelligent inspection system of transmission line as main content of UAV intelligent inspection system on transmission line. In the paper, principles of UAV inspection obstacle avoidance technology of transmission line are introduced. UAV inspection obstacle avoidance technology based on particle swarm global optimization algorithm is proposed after common obstacle avoidance technologies are studied. Stimulation comparison is implemented with traditional UAV inspection obstacle avoidance technology which adopts artificial potential field method. Results show that UAV inspection strategy of particle swarm optimization algorithm, adopted in the paper, is prominently better than UAV inspection strategy of artificial potential field method in the aspects of obstacle avoidance effect and the ability of returning to preset inspection track after passing through the obstacle. An effective method is provided for UAV inspection obstacle avoidance of transmission line.