A surgical stapling device particularly suited for endoscopic procedures is described The device includes a handle assembly and an elongated body extending distally from the handle assembly The distal end of the elongated body is adapted to engage a disposable loading unit A control rod having a proximal end operatively connected to the handle assembly includes a distal end extending through the elongated body A control rod locking member is provided to prevent movement of the control rod until the disposable loading unit is fully secured to the elongated body of the stapling device

Surgical Stapling Apparatus

Most of the signal processing that we will study in this course involves local operations on a signal, namely transforming the signal by applying linear combinations of values in the neighborhood of each sample point. You are familiar with such operations from Calculus, namely, taking derivatives and you are also familiar with this from optics namely blurring a signal. We will be looking at sampled signals only. Let's start with a few basic examples. Local difference Suppose we have a 1D image and we take the local difference of intensities, DI(x) = 1 2 (I(x + 1) − I(x − 1)) which give a discrete approximation to a partial derivative. (We compute this for each x in the image.) What is the effect of such a transformation? One key idea is that such a derivative would be useful for marking positions where the intensity changes. Such a change is called an edge. It is important to detect edges in images because they often mark locations at which object properties change. These can include changes in illumination along a surface due to a shadow boundary, or a material (pigment) change, or a change in depth as when one object ends and another begins. The computational problem of finding intensity edges in images is called edge detection. We could look for positions at which DI(x) has a large negative or positive value. Large positive values indicate an edge that goes from low to high intensity, and large negative values indicate an edge that goes from high to low intensity. Example Suppose the image consists of a single (slightly sloped) edge:

http://ieeexplore.ieee.org/iel5/5/31307/01456462.pdf

Linear systems

Wide bandgap semiconductors show superior material properties enabling potential power device operation at higher temperatures, voltages, and switching speeds than current Si technology. As a result, a new generation of power devices is being developed for power converter applications in which traditional Si power devices show limited operation. The use of these new power semiconductor devices will allow both an important improvement in the performance of existing power converters and the development of new power converters, accounting for an increase in the efficiency of the electric energy transformations and a more rational use of the electric energy. At present, SiC and GaN are the more promising semiconductor materials for these new power devices as a consequence of their outstanding properties, commercial availability of starting material, and maturity of their technological processes. This paper presents a review of recent progresses in the development of SiC- and GaN-based power semiconductor devices together with an overall view of the state of the art of this new device generation.

A Survey of Wide Bandgap Power Semiconductor Devices

Light-Emitting Diodes. (Monographs in Electrical and Electronic Engineering.) By A. A. Bergh and P. J. Dean. Pp. viii+591. (Clarendon: Oxford; Oxford University: London, 1976.) £22.

/pdf/light-emitting-diodes-ubzde6g9qc.pdf

Light-emitting diodes

A surgical stapling instrument (1) comprises a body portion (2, 3), a handle (4) and a staple fastening assembly (8). The staple fastening assembly (8) includes a curved cartridge (10), which comprises at least one curved open row of staples, and a curved anvil (22), which is adapted to cooperate with the cartridge (10) for forming the ends of the staples exiting from the cartridge (10). The staple fastening assembly (8) is adapted to allow unobstructed access towards the concave inner faces of the cartridge (10) and the anvil (22). The cartridge (10) can be moved towards the anvil (22) from a spaced position for positioning tissue therebetween to a closed position for clamping the tissue. Preferably, a knife is contained within the cartridge (10) and is positioned such that there is at least one row of staples on at least one side of the knife.

Surgical stapling instrument

The transmission line busbar filter is a good choice for a high-density EMI containment solution. This paper presents a study of the application of a transmission-line busbar filter in a motor drive system. To examine the potential improvement for busbar filters, low-frequency attenuation and basic modeling of busbar filters in a motor drive are studied. Based on the knowledge gained from the modeling, an improved busbar filter is proposed and fabricated. Experimental results show a significant improvement on busbar filter attenuation.

An improved design for transmission line busbar EMI filter

As is the case with several other mechanical power takeoffs (PTOs), the mechanical-motion-rectifier-based PTO consists of components, such as one-way clutches, gears, a ball screw, mechanical couplings, and a generator. Equivalent circuit models have been created in this article to describe the dry frictions, viscous damping, and mechanical compliances in these components, so the nonideal efficiency and nonlinear force of the PTO can be predicted in electrical simulations by integrating these subcircuit models. The circuit model is simplified, and its parameters are categorized as dc and ac unknowns. The dc and ac tests on the PTO are performed sequentially to extract two sets of parameters through linear regression or nonlinear curve fitting. Then, the model is validated through its prediction capability over 25 test conditions on input forces, output voltages, and efficiencies, with correlation coefficients of 0.9, 0.98, and 0.981, respectively.

Circuit Modeling of the Mechanical-Motion Rectifier for Electrical Simulation of Ocean Wave Power Takeoff

The current method for extracting the short-circuit broadband extended cantilever model (BECM) parameters requires measurement of short-circuit currents, and is problematic over a wide frequency range, prohibiting each short-circuit parameter to be directly measured. The improved method presented herein eliminates the measurements of short-circuit currents. Each short-circuit BECM parameter is directly found from two measurements, an open-circuit voltage gain and a short-circuit admittance. The method is demonstrated for a published five-winding BECM.

Improved method to extract the short-circuit parameters of the BECM

Recent reports have shown the reliability of direct-bond-copper (DBC) substrates was significantly improved by sealing their edges with polymeric materials. In this work, DBC substrates with and without sealed edges had been prepared. Parylene HT and Nusil R-2188 had been chosen as sealing materials. Parylene HT was applied to the edges of the DBC by chemical vapor deposition (CVD), and Nusil R-2188 by programmable fluid dispensing. The DBC substrates with and without sealed edges were cycled between −55°C to 200°C. The cycled substrates were monitored by optical microscope and scanning electron. DBC substrates whose edges were not sealed were found to fail in approximately 100 cycles. No failure was observed in DBC substrates coated with parylene HT before 300 cycles. Samples whose edges were sealed with Nusil R-2188 exhibited the highest lifetime under the thermal cycling condition of −55°C – 200°C. After 300 cycles, neither detachment of Nusil from DBC surfaces nor failure at Cu/Al2O3 interface was det...

High-Temperature Reliability of Direct-Bond-Copper Substrates with Sealed Edges

3D-printing has the potential to ease fabrication of novel magnetic components that lead to miniaturization of power electronic devices. The main challenge lies in the lack of functional magnetic feedstock that has many choices of different magnetic permeabilities. NiCuZn ferrite feedstock was developed of which the permeability was tailored by adding different fractions of silica particles. This paper developed a formulation guideline of the feedstock, which prescribes the fraction of silica to add from the target permeability of the feedstock. To study the mechanisms of the effects of silica on permeability of the ferrite feedstock, the feedstock was 3D printed into toroid cores and the permeability, density, and microstructure were characterized. Formulas from existing models describing the different aspects of the silica’s effects on the ferrite were evaluated and combined to build the guideline. The guideline accurately predicted permeability of the composite ferrite when silica was

Khai D. T. Ngo

Papers

An improved design for transmission line busbar EMI filter

Circuit Modeling of the Mechanical-Motion Rectifier for Electrical Simulation of Ocean Wave Power Takeoff

Improved method to extract the short-circuit parameters of the BECM

High-Temperature Reliability of Direct-Bond-Copper Substrates with Sealed Edges

Effects of SiO2 inclusions on sintering and permeability of NiCuZn ferrite for additive manufacturing of power magnets