The present disclosure discloses a unipolar antenna, a wireless access apparatus and a wireless router. The unipolar antenna of the present disclosure comprises a medium substrate, as well as a power feeding point, a feeder line and a metal structure that are disposed on a surface of the medium substrate. The feeder line is connected to the power feeding point, and the feeder line and the metal structure are coupled with each other. The unipolar antenna, the wireless access apparatus and the wireless router of the present disclosure can transmit or receive electromagnetic signals of two or more different wavebands simultaneously so that they can operate within multiple operation wavebands in a single-frequency mode and operate within different operation wavebands simultaneously in a multi-frequency mode. Thereby, the antenna can be miniaturized on the premise of satisfying the performance requirements of the communication devices.

With advancement of the wireless communication technologies, requirements on wireless communication devices become ever higher. For antennas that function to transmit and receive electromagnetic (EM) signals, a number of structures have been developed to satisfy requirements of the communication devices. This imposes greater challenges in terms of performances or structures of the antenna.
An antenna acts as a transmitting unit and a receiving unit for RF signals, and the operation performances thereof have a direct influence on the operation performance of the overall electronic system. However, some important parameters of the antenna such as the size, the bandwidth and the gain are restricted by the basic physical principles (e.g., the gain limit and the bandwidth limit under the limitation of a fixed size). The limits of these parameters make miniaturization of the antenna much more difficult than miniaturization of other components; and furthermore, due to complexity of analysis of the electromagnetic field of the RF component, even approximately reaching these limits represents a great technical challenge.
For a conventional antenna, the radiating operation frequency thereof is positively correlated with the size of the antenna directly, and the bandwidth is positively correlated with the area of the antenna, so the antenna usually has to be designed to have a physical length of a half wavelength. Besides, in some more complex electronic systems, an additional impedance matching network needs to be disposed at the upstream of the in feed antenna. However, the additional impedance matching network adds to the complexity in design of the feeder line of the electronic systems and increases the area of the RF system and, meanwhile, the impedance matching network also leads to a considerable energy loss. This makes it difficult to satisfy the requirement of a low power consumption in the system design. Due to the limitation of functions of the antenna themselves, most of the current antenna are applied externally to apparatuses and consume much space. Therefore, the functions and sizes of the antenna have become a technical bottleneck that hinders further reduction in volume of the apparatuses that adopt the antenna. Accordingly, how to provide a miniaturized and high-performance antenna for modern electronic integrated systems has become an important technical problem to be tackled.
Additionally, the demands for built-in antennas in various wireless communication devices become increasingly higher. For example, various electronic apparatuses such as wireless access apparatuses and wireless routers substantially all adopt external antennas, which greatly limits the room for industrial design and mechanism design of the products. Moreover, the external antennas necessitate design of a corresponding impedance matching connector and a corresponding mechanism module, which almost account for 90% or more of the cost of the whole antenna. In turn, the increased cost of the whole antenna further drives the cost of the electronic apparatus (e.g., a wireless access apparatus or a wireless router) to increase correspondingly. In contrast, using a built-in antenna will greatly save the cost of the connector and the mechanism module.

Unipolar antenna, wireless access apparatus and wireless router

High-Tech Industrial Estate, Nanshan District, Shenzhen, Guangdong

KUANG-CHI INSTITUTE OF ADVANCED TECHNOLOGY


An optical disc apparatus is provided, which comprises a lens tilting section for tilting an objective lens to correct coma aberration occurring in a light beam spot focused on an information surface of an optical disc, a spherical aberration correcting section for correcting spherical aberration occurring in a light beam spot focused on the information surface, and a lens tilt-spherical aberration correction control section for controlling the spherical aberration correcting section to change an amount of spherical aberration correction performed by the spherical aberration correcting section depending on a tilt of the objective lens tilted by the lens tilting section.

1. Field of the Invention
The present invention relates to an optical disc apparatus and a spherical aberration correction controlling apparatus.
2. Description of the Related Art
Recently, optical discs, such as DVD-ROM, DVD-RAM, DVD−RW, DVD−R, DVD+RW, DVD+R, and the like, have been developed as high density/large capacity recording media.
To date an optical lens having a numerical aperture (NA) of 0.6 has been used as an objective lens of an optical disc apparatus for recording information onto the above-described optical discs and/or reproducing information from those optical discs. In order to obtain an optical disc having a higher density/larger capacity (e.g., a Blue-ray Disc (BD), etc.), the use of a blue-violet laser and an optical lens having an NA of 0.8 or more has been studied.
For the above-described optical discs, a multi-layer structure having two or more recording layers (information surfaces) has been studied.
Hereinafter, lens tilt control and spherical aberration correction performed by conventional optical disc apparatuses will be described (see Japanese Laid-Open Publication No. 2002-157750 (particularly, paragraphs 0070 to 0101, and FIGS. 1 to 8)).
FIG. 13 is a block diagram showing a conventional optical disc apparatus 300. The optical disc apparatus 300 records information onto an optical disc 320 and reproduces information from the optical disc 320.
The optical disc 320 has an information surface for recording information (not shown in FIG. 13) and a protection layer for protecting the information surface provided on the information surface (not shown in FIG. 13). In addition, tracks are provided on the information surface of the optical disc 320.
An optical head section 350 comprises: a light source 303, such as a semiconductor laser or the like, which serves as a light beam generating section; a light receiving section 304 for receiving a light beam which is output from the light source 303 and is thereafter reflected from the optical disc 320; an optical system 352; and an optical drive section 354 for driving the optical system 352.
The optical system 352 comprises an objective lens 301 and a pair of spherical aberration correcting lenses 315.
The spherical aberration correcting lenses 315 are a concave lens 315a and a convex lens 315b. Note that the concave lens 315a and the convex lens 315b may be arranged in a manner different from that shown in FIG. 13.
The optical drive section 354 comprises: a focus actuator 302 for moving the objective lens 301 in relation to the information surface of the optical disc 320; and a spherical aberration correcting actuator 334 for driving the spherical aberration correcting lenses 315 in a manner which changes a distance between the concave lens 315a and the convex lens 315b to prevent the occurrence of spherical aberration.
The optical disc apparatus 300 corrects spherical aberration which is attributed to a predetermined thickness of the protection layer of the optical disc 320 to improve the quality of a signal which is recorded onto or reproduced from the optical disc 320.
Focus control performed by the conventional optical disc apparatus 300 will be described below.
The optical disc apparatus 300 rotates the optical disc 320 (information carrier) at predetermined rpm by means of a disc motor 310.
A light beam output from the light source 303 is focused by the objective lens 301 onto the information surface of the optical disc 320, thereby forming a light beam spot. At the light beam spot, the light beam is reflected from the optical disc 320. The reflected light beam is passed through the objective lens 301 again and is thereafter input to the light receiving section 304.
The light receiving section 304 has four separate regions. Each region generates a photocurrent, the amount of which depends on the amount of light received by the region. The light receiving section 304 outputs the generated photocurrent to a preamplifier 306.
The preamplifier 306 serves as an I/V converter to convert the photocurrent into a voltage. The preamplifier 306 outputs a voltage signal, which has been converted from a current signal, to a focus error signal generator 307.
The focus error signal generator 307 generates a focus error signal indicating a deviation (error) of the light beam spot in a direction perpendicular to the optical disc 320 based on the four signals output from the preamplifier 306. Hereinafter, the focus error signal is also referred to as an FE signal.
For example, the focus error signal generator 307 uses an astigmatism correction method to generate an FE signal. The focus error signal generator 307 outputs the generated FE signal to a focus control circuit 317.
The focus control circuit 317 subjects the FE signal to a filter operation, such as phase compensation, gain compensation, or the like. Thereafter, the focus control circuit 317 outputs the FE signal to a focus actuator driving circuit 309.
The focus actuator driving circuit 309 generates a drive signal based on the FE signal output from the focus control circuit 317, and outputs the generated drive signal to the focus actuator 302.
The focus actuator 302 serves as an objective lens moving section. The focus actuator 302 moves the objective lens 301 in a direction substantially perpendicular to the information surface of the optical disc 320 based on the drive signal output from the focus actuator driving circuit 309, thereby changing the focus position of the light beam.
The focus control circuit 317 controls the focus actuator driving circuit 309 in a manner which causes the FE signal generated by the focus error signal generator 307 to be substantially zero. As a result, the light beam spot is in focus to a predetermined level on the information surface of the optical disc 320. In this manner, focus control is achieved.
Next, the lens tilt control of the conventional optical disc apparatus 300 will be described.
A tilt control section 319 outputs a tilt control signal to a tilt actuator driving circuit 326 in accordance with a command output from a microcomputer 308.
The tilt actuator driving circuit 326 applies offset signals having different polarities to two drive signals output from the focus actuator driving circuit 309 based on the tilt control signal. In other words, the tilt actuator driving circuit 326 makes a predetermined difference between the two drive signals output from the focus actuator driving circuit 309.
With the offset signals from the tilt actuator driving circuit 326, one side of the objective lens 301 is lowered, while the other side thereof is raised. Thus, the objective lens 301 can be tilted depending on the tilt of the optical disc 320, thereby making it possible to cancel a blurry light beam spot, i.e., coma aberration, which is attributed to the tilt of the information surface of the optical disc 320.
In the following descriptions, a technique for controlling the tilt of the objective lens 301 in a manner which cancels coma aberration attributed to the tilt of the optical disc 320, is also referred to as lens tilt control.
Hereinafter, lens tilt control will be described.
FIG. 14 is a schematic diagram for explaining a relationship between a tilt of the optical disc 320 and lens tilt control.
As shown in portion (a) of FIG. 14, the optical disc 320 is ideally placed perpendicularly to a light beam output from the light source 303. When the optical disc 320 is perpendicular to the light beam, the objective lens 301 is also placed perpendicularly to the light beam. Thereby, coma aberration does not occur in a light beam spot on the information surface of the optical disc 320, so that reproduction and recording can be satisfactorily performed.
In actual situations, however, the optical disc 320 may not be perpendicular to a light beam output from the light source 303. For example, when the optical disc 320 is warped, the peripheral portion of the optical disc 320 is not perpendicular, i.e., is tilted, with respect to the light beam output from the light source 303.
It is assumed that the optical disc 320 is tilted from a direction perpendicular to a light beam. In this case, if the objective lens 301 remains perpendicular to the light beam, coma aberration occurs in a light beam spot on the information surface of the optical disc 320, so that the light beam is not correctly brought into focus. As a result, reproduction/recording performance is lowered.
To avoid the above-described problem, the objective lens 301 is tilted to face in the same direction as that of the optical disc 320 as shown in portions (b) and (c) of FIG. 14. As a result, it is possible to cancel coma aberration which occurs in a light beam spot on the information surface of the optical disc 320. Thus, reproduction and recording can be satisfactorily performed.
The objective lens 301 is tilted toward the same direction as that of the tilted optical disc 320. However, the tilt of the objective lens 301 may not be exactly equal to the tilt of the optical disc 320. The tilt of the objective lens 301 may be optimally determined based on an optical constant(s) of the objective lens 301.
Next, spherical aberration correction will be described with reference to the optical disc apparatus 300 of FIG. 13.
A spherical aberration correction control section 335 outputs a spherical aberration correction signal to a spherical aberration correction driving circuit 333 in accordance with a command output from the microcomputer 308.
The spherical aberration correction driving circuit 333 generates a drive signal based on the spherical aberration correction signal, and outputs the generated drive signal to the spherical aberration correcting actuator 334.
The spherical aberration correcting actuator 334 drives the spherical aberration correcting lens 315 based on the drive signal.
The spherical aberration correcting actuator 334 changes a distance between the concave lens 315a and the convex lens 315b (spherical-aberration correcting lenses 315) based on the drive signal output from the spherical aberration correction driving circuit 333 to correct spherical aberration which occurs in a light beam spot. Thus, it is possible to correct a blurry light beam spot (i.e., spherical aberration) which occurs on the information surface of the optical disc 320. That is, spherical aberration correction can be achieved.
Further, spherical aberration correction will be described below.
FIG. 15 is a cross-sectional view showing a state of a light beam in relation to the optical disc 320. As described above, the optical disc 320 comprises a protection layer 321 for protecting an information surface 329, the protection layer 321 being provided on the information surface 329.
Portion (a) of FIG. 15 shows the case where the thickness of the protection layer 321 from the surface of the optical disc 320 to the information surface 329 is optimum, so that spherical aberration does not occur on the information surface 329.
Portion (b) of FIG. 15 shows the case where the thickness of the protection layer 321 from a surface of the optical disc 320 to the information surface 329 is smaller than the optimum value, so that spherical aberration occurs on the information surface 329.
Hereinafter, an inner portion and an outer portion of the light beam will be described separately.
It is assumed that the above-described focus control is being performed. In this case, the protection layer 321 of the optical disc 320 diffracts a light beam output from the light source 303 of the optical disc apparatus 300, so that the outer portion of the light beam is brought into focus B while the inner portion thereof is brought into focus C.
In portion (a) of FIG. 15, spherical aberration does not occur on the information surface 329 of the optical disc 320, so that the focus B of the outer portion of the light beam and the focus C of the inner portion of the light beam share the same position A. In this case, the position A exists on the information surface 329. An equidistant surface from the position A corresponds to the wavefront of the light beam.
However, as shown in portion (b) of FIG. 15, when the thickness of the protection layer 321 is smaller than the optimum value, spherical aberration occurs.
Specifically, the focus B and the focus C are separated from each other and both are displaced from the position A of the information surface 329, i.e., the light beam is defocused. In this case, the wavefront of the light beam does not correspond to the equidistant surface from the position A. In this case, an FE signal is generated irrespective of the outer and inner portions of the light beam, and focus control is performed in a manner which causes the FE signal to be substantially zero. Therefore, the position A indicating the focus position of the whole light beam is located on the information surface 329.
In portion (b) of FIG. 15, solid lines indicate the inner and outer portions of a light beam when spherical aberration occurs, while broken lines indicate the inner and outer portions of a light beam when spherical aberration does not occur.
Also, when the thickness of the protection layer 321 ranging from a surface of the optical disc 320 to the information surface 329 is greater than the optimum value, the focus B and the focus C are separated from each other and both are displaced from the position A of the information surface 329, i.e., the light beam is defocused, in a manner similar to that shown in portion (b) of FIG. 15.
Thus, particularly when an optical lens having a large numerical aperture (NA) of 0.8 or more is used, spherical aberration, which occurs due to the uneven thickness of a protection layer for protecting the information surface of an optical disc and errors in the distance between the surface of a multi-layer optical disc and the information surface of each layer, is not negligible. In order to remove the influence of such spherical aberration, a method for switching the levels of correction of spherical aberration so as to achieve a multi-layer structure has been proposed.
In the optical disc apparatus 300, when spherical aberration occurs, spherical aberration is corrected by changing the distance between the concave lens 315a and the convex lens 315b to modify the outer and inner portions of a light beam.
According to the above-described conventional technique, an objective lens is tilted so that coma aberration which occurs in a light beam spot due to the warp of an optical disc can be canceled.
However, in the conventional technique, when the objective lens is tilted so as to cancel coma aberration, spherical aberration occurs due to the tilt of the objective lens in addition to that which occurs due to influences, such as the uneven thickness of the protection layer of a disc or the like.
Therefore, even if coma aberration is canceled by the lens tilt control, additional spherical aberration is caused by the lens tilt control. As a result, recording/reproduction performance is lowered.

Optical disc apparatus and spherical aberration correction controlling apparatus

Matsushita Electric Industrial Co., Ltd.


A non-invasive dry coupled disposable/reusable ultrasonic sensor has a housing and a piezoelectric element at one end of the housing to which connected signal leads are connected that extend out from the housing. A piece of double-sided adhesive tape has one adhesive side secured directly to the face at the one end of the housing with the other adhesive side to be secured directly to the outer surface of a pipe or vessel. The tape can cover the entire face of the one end of the housing or only that part that the piezoelectric element faces.

Transducers, or sensors, for transmitting and receiving ultrasonic energy in applications involving liquids are well known. A typical application for such transducers is in liquid level sensing to sense the height of a liquid in a tube or pipe or a container or other vessel, such as a tank. The term vessel as used hereinafter includes any type of a vessel such as a tank or other liquid container and the term tube includes pipes of metal or plastic and tubing of flexible or rigid material. Another application is use with a tube to transmit and receive ultrasonic energy across a defined space so as to sense the presence of air bubble or particles flowing in the tube so that they can be counted and characterized, such as by size, by a computer. Still a further application is in flow meters where the rate of flow in a pipe is measured.
One widely used form of such transducer has a housing that contains a piezo-electric element. The housing is mounted to the vessel or tube with the front end of the housing extending trough a hole placed to be in direct contact with the liquid. The ultrasonic energy is coupled directly to the liquid to sense its presence or the energy dissipates in air when no liquid is present.
Another type of ultrasonic transducer is of the non-contact type, such as disclosed in U.S. Pat. No. 4,630,245, granted Dec. 16, 1986. Here, the transducer housing is of a rigid material, such as a plastic, and is fixedly mounted, such as by a clamp or strap, to the outside of the vessel or tube in which the liquid being sensed is present. The non-contact type transducer has an advantage in that no hole has to be made in the vessel or tube to which it is mounted but it requires a coupling compound, such as Vaseline, or silicon grease, between the housing and the vessel or tube. The coupling compound is needed so that there will be no air gaps between the end of the transducer housing through which ultrasonic energy enters or is transmitted and the vessel or tube since this would adversely affect the transmission and reception of the ultrasonic energy from the transducer to the wall of the vessel or tube and thereafter to the liquid or air therein.
Application of the coupling compound in the foregoing type of non-contact transducer is another step required in the mounting of the transducer. The need for using a coupling compound also limits the use of such a transducer, for example, in an application for sensing the liquid level in bottles moving rapidly past a fixed inspection point on an assembly line. Here, it would not be possible to apply the coupling compound to each of the bottles. Also, in some applications, the use of a coupling compound can adversely affect the appearance of the tube or vessel. Further, in sensitive sanitary applications such as drug and food processing, the use of such coupling compound should or must be avoided. Another disadvantage in this type of non-contact transducer is that it is fixed in position and cannot be easily moved.
U.S. Pat. No. 6,781,287 to Naim Dam, et al, granted Aug. 24, 2004, which is assigned to the assignee of the subject application discloses an ultrasonic transducer that has a capsule, or head, of a flexible and deformable material that contacts the outer surface of the pipe or vessel. The piezoelectric element is within the capsule which also contains a fluid, such as oil, that serves as the coupling agent. While this transducer does not require a coupling agent external of the transducer housing, it is somewhat complicated and relatively expensive to manufacture.
Accordingly, a need exists for a non-contact type ultrasonic transducer that is not subject to the limitations of requiring either an externally applied coupling compound or external mounting devices. It is also preferred that such a transducer be as economical as possible so that it can be disposable when used in certain applications, such as medical procedures.

Non-invasive dry coupled disposable/reusable ultrasonic sensor


There is provided a nuclear reprogramming factor for a somatic cell, which comprises a gene product of each of the following three kinds of genes: an Oct family gene, a Klf family gene, and a Myc family gene, as a means for inducing reprogramming of a differentiated cell to conveniently and highly reproducibly establish an induced pluripotent stem cell having pluripotency and growth ability similar to those of ES cells without using embryo or ES cell.

Embryonic stem cells (ES cells) are stem cells established from human or mouse early embryos which have a characteristic feature that they can be cultured over a long period of time while maintaining pluripotent ability to differentiate into all kinds of cells existing in living bodies. Human embryonic stem cells are expected for use as resources for cell transplantation therapies for various diseases such as Parkinson's disease, juvenile diabetes, and leukemia, taking advantage of the aforementioned properties. However, transplantation of ES cells has a problem of causing rejection in the same manner as organ transplantation. Moreover, from an ethical viewpoint, there are many dissenting opinions against the use of ES cells which are established by destroying human embryos. If dedifferentiation of patients' own differentiated somatic cells could be induced to establish cells having pluripotency and growth ability similar to those of ES cells (in this specification, these cells are referred to as "induced pluripotent stem cells (iPS cells)", though they are sometimes called "embryonic stem cell-like cells" or "ES-like cells"), it is anticipated that such cells could be used as ideal pluripotent cells, free from rejection or ethical difficulties.
As a method for reprogramming a somatic nucleus, for example, a technique of establishing an embryonic stem cell from a cloned embryo, prepared by transplanting a nucleus of a somatic cell into an egg, was reported (W. S. Hwang et al., Science, 303, pp. 1669-74, 2004; W. S. Hwang et al., Science, 308, pp. 1777-83, 2005: these articles were, however, proved to be fabrications and later withdrawn). However, this technique of preparing the cloned embryo only for the purpose of establishing ES cells, has rather more serious ethical problems when compared with ordinary ES cells using surplus embryos produced in fertilization therapy. A technique of reprogramming a somatic cell nucleus by fusing a somatic cell and an ES cell was also reported (M. Tada et al., Curr. Biol., 11, pp. 1553-1558, 2001; C. A. Cowan et al., Science, 309, pp. 1369-73, 2005). However, this method results in the use of human ES cells, which fails to provide a solution to the ethical difficulties. Further, a technique of reprogramming a cell nucleus by reacting an extract of a cell strain, derived from a germ cell tumor generated in a human, with a differentiated cell was reported (C. K. Taranger et al., Mol. Biol. Cell, 16, pp. 5719-35, 2005). However, it was completely unknown which component in the extract induced the reprogramming in this method, and therefore, this method has problems of technical reliability and safety.
A method for screening a nuclear reprogramming factor having an action of reprogramming differentiated somatic cells to derive induced pluripotent stems cell was proposed (International Publication WO2005/80598). This method comprises the steps of contacting somatic cells containing a gene, in which a marker gene is positioned so as to receive expression control by an expression control region of the ECAT (ES cell associated transcript) genes (i.e., a class of genes specifically expressed in ES cells), with each test substance; examining presence or absence of the appearance of a cell that expresses the marker gene; and choosing a test substance inducing the appearance of said cell as a candidate of a nuclear reprogramming factor for somatic cells. A method for reprogramming a somatic cell is disclosed in Example 6 and the like of the above publication. However, this publication fails to report an actual identification of a nuclear reprogramming factor.
Patent document 1: International Publication WO2005/80598


An image sensor includes a first photodiode formed in a semiconductor substrate at a depth reachable by red light, a second photodiode disposed on or over the first photodiode in the semiconductor substrate at a depth reachable by blue light, a third photodiode disposed adjacent to the second photodiode, a plug connected to the first photodiode, transistor structures on the semiconductor substrate and electrically connected with the first, second and third diodes, an insulating layer covering the transistor structures, and microlenses on the insulating layer.

Embodiments of the invention relate to an image sensor and a method of fabricating the same.
Image sensors are semiconductor devices for converting optical images into electrical signals, and are mainly divided into a charge coupled device (CCD) image sensor and a complementary metal oxide semiconductor (CMOS) image sensor. The CCD is a kind of semiconductor device in which metal/oxide/silicon (MOS) capacitors are positioned closely to each other and charge carriers are stored in the capacitors and transferred. The CMOS image sensor employs a switching mode to detect an output of a photo detector using MOS transistors corresponding to the number of pixels, which areprovided through a CMOS technology that uses peripheral devices,such as a control circuit and a signal processing circuit.
In the CMOS image sensor, a color filter layer is formed on a pixel array so as to selectively transfer light having a specific wavelength to a photodiode, thereby realizing an image.
However, in the above method of realizing the image, pixels for realizing a single color can take a wide area. For instance, an image sensor including red, green and blue (RGB) color filters (which process natural light according to three main colors) requires three pixels for detecting a red color, a green color and a blue color. Accordingly, a technique for improving there solution of the image sensor made by the above method is desired.

Image sensor and method of fabricating the same


A hot runner system having a melt distribution system that is reusable and reconfigurable to vary drop or nozzle locations to meet various design requirements. The melt distribution system includes a melt distributor in fluid communication with a melt source, at least one melt conduit in fluid communication with the melt distributor, and at least one nozzle in fluid communication with the at least one melt conduit. The hot runner system also includes a backing plate; a manifold plate detachably connected to the backing plate; a melt distribution system positioned between the backing plate and the manifold plate and having at least one nozzle associated therewith. The hot runner system may be configured and reconfigured to accommodate various drop or nozzle locations.

A hot runner is utilized to transfer molten material, typically plastic resin, from an injection unit of an injection molding machine to at least one cavity defined in a pair of mold plates. A hot runner typically includes a manifold plate, a manifold housed in the manifold plate, and a backing plate that supports the manifold and manifold plate. The hot runner routes molten material from a central sprue, which connects to an injection unit on an injection molding machine, to a plurality of nozzles which inject the molten material into cavities in the mold. The hot runner divides the flow of molten material into several branches as it flows from the central sprue to the nozzles.
Referring now to FIG. 1, a cross-section of a hot runner 8 is shown. A manifold 10 is located between a manifold plate 12 and a backing plate 14. The manifold 10 has one or more melt channels 18 that communicate the molten material from a sprue 16 connected to the manifold 10 at a central location. The hot runner 8 has nozzles 6 in fluid connection with the manifold 10.
One limitation of this prior art hot runner 8 is that the manifold 10, manifold plate 12, and backing plate 14 must be replaced each time a new hot runner 8 is desired. The possibility of a reusable and reconfigurable manifold 10 (or melt distribution system), manifold plate 12, backing plate 14 represents a significant potential cost and time saving benefit. In addition to these cost and time benefits, lead times for a new hot runner 8 can be considerable and with the present invention significantly reduces lead time.
Therefore, it would be desirable to provide a hot runner 8 that is reusable and reconfigurable. Specifically, it would be very desirable to provide manifolds 10 (or melt distribution systems), manifold plates 12, and backing plates 14 that are reusable and reconfigurable to different drop locations. Further, it would be desirable to have nozzles 6 that are reusable as well.
The present invention is directed to meeting one or more of the above-stated desirable objectives.


A method, apparatus, and computer readable medium for creating asides within an electronic document are provided. The keystroke combination is defined for creating an aside with an electronic document. If the keystroke combination is received, a location is identified within the electronic document for an aside object. Once the location for the aside has been determined, an outline object is created at the location. The outline object holds text or other contents for the aside. An insertion point is then placed within the object. The user may then enter keystrokes or other data into the second object. If the keystroke combination is again entered, the insertion point is returned to its location immediately prior to moving the insertion point to the aside object. The keystroke combination for creating an aside and the keystroke combination for returning from the aside may be identical. Asides may also be created in various portions of an electronic document, such as a title portion, in a similar manner.

When taking handwritten notes on a particular topic, it is common to exit the main body of notes, write down something elsewhere on the page, and return to the main body of notes. This activity is commonly referred to as creating an "aside" to the main body of notes. Asides may be necessary to write down an idea completely unrelated to the main body of notes, or a reminder, such as a reminder to buy a birthday gift for a relative. Asides such as these are frequently created at a place where the content will stand out from the rest of the content on the page, such as in the page margins or at the top of a page. Alternatively, asides may be used to create the beginning of a new subset of notes somewhere else on the page that will be used at a later time. The note taker can then easily jump back to the original position within the main body of notes and return to where they left off.
Creating asides using a pen and paper is a trivial task. A note taker simply finds some empty space on the page, creates the aside, and then returns the pen to their previous position. However, creating asides in an electronic document is not so easy, especially for touch typists that do not like to remove their hands from the computer keyboard. Currently, to create an aside within an electronic document, such as a word processing document, the user must take their hands off of the keyboard, grasp a computer mouse or other pointing device, locate space within the electronic document for the aside, and then select the desired location. The user must then return their hands to the keyboard and type the contents of the aside.
When the user has finished typing the contents of the aside, the user must again grasp the mouse or other pointing device, take time to find the location where they were typing prior to creating the aside, and then select the location. The user may then return their hands to the keyboard to begin typing where they left off. This process involves many steps and can be extremely time consuming and frustrating for users, especially users that prefer a keyboard to a mouse. Therefore, there is a need for an improved method for creating asides within an electronic document that reduces the number of steps required to create an aside.

Method, apparatus, and computer-readable medium for creating asides within an electronic document


While no signals are being supplied to first and second drive circuits, the drive circuits keep supplying idling currents to the bases of first and second transistors which constitute a push-pull amplifier. A first control circuit is provided in the base-emitter path of the first transistor, to control the first transistor in accordance with an input signal. A second control circuit is provided in the base-emitter path of the second transistor, to control the second transistor in accordance with an input signal. The first control circuit comprises a third transistor, a first resistor connected between the collector and base of the third transistor, a third resistor connected between the collector of the third transistor and the base of the first transistor, a constant current source connected to the base of the third transistor. The second control circuit comprises a fourth transistor, a second resistor connected between the collector and base of the fourth transistor, a fourth resistor connected between the collector of the fourth transistor and the base of the second transistor, a constant current source connected to the base of the fourth transistor.

The present invention relates to an amplifier for use in, for example, audio apparatuses, and more particularly to an amplifier which performs push-pull amplification on the input signal, thereby acquiring a high current efficiency.
FIG. 8 shows a conventional circuit disclosed in Jpn. Pat. Appln. KOKAI Publication 4-111507, which is designed for use in the output section of an audio apparatus. The circuit comprises two drive circuits A1 and A2, four transistors Q11 to Q14, two input terminals 71 and 72, a power-supply terminal 73, an output terminal 74, and a ground terminal 75. The inputs of the drive circuits A1 and A2 are connected to the input terminals 71 and 72, respectively. The transistors Q11 and Q13 constitute a first current mirror circuit, and the transistors Q12 and Q14 constitute a second current mirror circuit. The output of the drive circuit A1 is connected to the collector of the transistor Q11 and also to the bases of the transistors Q11 and Q13. The collector of the transistor Q13 is connected to the power-supply terminal 73. The emitter of the transistor Q13 is connected to the output terminal 74, together with the emitter of the transistor Q11. The output of the drive circuit A2 is connected to the collector of the transistor Q12 and also to the bases of the transistors Q12 and Q14. The collector of the transistor Q14 is connected to the output terminal 74. The emitter of the transistor Q14 is connected to the ground terminal 75, together with the emitter of the transistor Q12.
In the circuit shown in FIG. 8, an input signal A is supplied to an input terminal 71 through a capacitor C2, while an input signal /A, which is opposite to the signal A, in phase is supplied to the other input terminal 72 through a capacitor C3. The circuit operates as a push-pull amplifier. When its output terminal 74 is connected to a load RL through a capacitor C1, the circuit supplies the load RL with a current which is a product of the output current of the drive circuit A1 and the current mirror ratio of the first current mirror circuit or with a current which is a product of the output current of the drive circuit A2 and the current mirror ratio of the second current mirror circuit.
The drive circuit A1 and the transistors Q11 and Q13 constitute a first amplifier circuit, which amplifies the positive half of the input-signal wave. The drive circuit A2 and the transistors Q12 and Q14 constitute a second amplifier circuit, which amplifies the negative half of the input-signal wave. The first and second amplifier circuits are identical in structure. The circuit shown in FIG. 8 therefore has but a little distortion rate.
Both drive circuits A1 and A2 output an idling current each, even while they are receiving no input signals. Therefore, a current which is the product of the idling current and the current mirror ratio of the first current mirror circuit flows through the transistor Q13, and a current which is the product of rib the idling current and the current mirror ratio of the second current mirror circuit flows through the transistor Q14. Hence, the crossover distortion in the circuit of FIG. 8 is small.
To have a great amplification factor, either current mirror circuit needs to have a large current mirror ratio. If the current mirror circuits have their current mirror ratios increased, however, the idling currents flowing in the transistors Q13 and Q14 while no signals are being supplied to the drive circuits A1 and A2 will increase. Consequently, the circuit of FIG. 8 will consume more power.
FIG. 9 shows a B-class push-pull amplifier which is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 8-2009. In this amplifier, the transistors Q8 and Q10 remains on while no signals are being supplied to the input terminals 71 and 72. The emitter-current path between the diode-connected transistors Q7 and Q9 is rendered conducting. As long as this path remains conducting, the transistors Q7, Q8 and Q11 constitute a current mirror circuit, and the transistors Q9, Q10 and Q12 constitute a current mirror circuit. While no signals are being supplied to the input terminals 71 and 72, the idling current (i.e., output current) of either current mirror circuit is determined by the current mirror ratio.
While input signals are being supplied to the input terminals 71 and 72, the transistors Q8 and Q10 are alternately turned off in accordance with the polarities of the input signals. As a result, the transistors Q7 and Q9 are alternately turned off. When the transistor Q7 is off, all collector current of the transistor Q5 is supplied to the base of the transistor Q11. When the transistor Q9 is off, all collector current of the transistor Q3 is supplied to the base of the transistor Q12. The output current supplied from the output terminal 74 therefore depends on the current amplification factor of the transistor Q11 or Q12.
As indicated above, the transistors Q8 and Q10 remain on while no signals are being supplied to the input terminals 71 and 72. In these transistors Q8 and Q10, a collector-emitter saturation voltage VCE(SAT) is generated. The voltage VCE(SAT) causes the idling current to change by the value determined by the emitter-area ratio of the transistors Q7 and Q9 and the emitter-area ratio of the transistors Q11 and Q12. The voltages VCE(SAT) of the transistors Q8 and Q10 are difficult to control during the manufacture.
Furthermore, when the push-pull amplifier has its maximum current amplification factor, the transistors Q3 and Q4 or the transistors Q5 and Q6 are turned off. Since, the transistors Q8 and Q10 are saturated while operating, some times elapses until the transistors Q3 and Q4 or the transistors Q5 and Q6 are turned on. This inevitably increases the possibility of ringing.

Amplifier having a high current efficiency


A portable clipboard is provided for use by medical professionals with a latching, pullout drawer with an integral storage area for prescription pads, medical forms and writing implements. The top surface incorporates a clip to secure documents and the pullout drawer can be moved to the open position while maintaining the top surface in position for writing.

Doctors and technical personnel use clipboards with a clamping mechanism along the top and hard writing surface to prepare documents. The primary advantage to the use of a clipboard is that it allows for a writing surface in situations that would otherwise not allow for a suitable surface for preparing written documents. Physicians and medical technicians typically require the use of a clipboard when preparing patient records, prescriptions and other medical documents. Often it is desirable to have prescription pads, record forms, etc. available during a patient visit, examination or testing period. Technicians in other fields share similar needs.
Various devices have been described in prior art incorporating clipping mechanisms and storage compartments. For example, the device described by Sinclair, U.S. Pat. No. 4,892,334, discloses a flat writing surface that is hinged along the top and lifts to reveal a storage compartment designed to transport pens, pencils, erasers, rulers and calculators.
Zalkind, U.S. Pat. No. 2,606,774, discloses a device to hold and automatically dispense sales slips or forms to the writing surface.
Liu et al., U.S. Pat. No. 4,896,927, describes a device incorporating a writing surface, clip and cover that can be rotated to cover and protect documents when not being written on or referred to.
Aimes, U.S. Pat. No. 2,805,870, discloses a device for holding a memo pad for the movable support of index cards.
Krepp, U.S. Pat. No. 5,046,760, describes a clipboard with hollow areas for storing drafting aids.
Each of these devices addresses the need for portable writing surfaces and in some cases storage of supplies, writing implements and drafting tools. The current invention goes beyond the present art to address the specific needs of the medical profession. It incorporates a surface area and clip to secure documents while also providing a secure pullout drawer to house a prescription pad and writing instruments.


A pillow is provided including an exterior extent defining an interior space and a pair of open ends. A pair of interior extents are included each having a hollow tubular configuration. Each interior extent has a length equal to that of the exterior extent and is situated within the interior space of the exterior extent in parallel relationship.

1. Field of the Invention
The present invention relates to pillows and more particularly pertains to a new portable pillow for allowing a user to comfortably rest his or her head in awkward and cramped areas.
2. Description of the Prior Art
The use of pillows is known in the prior art. More specifically, pillows heretofore devised and utilized are known to consist basically of familiar, expected and obvious structural configurations, notwithstanding the myriad of designs encompassed by the crowded prior art which have been developed for the fulfillment of countless objectives and requirements.
Known prior art pillows include U.S. Pat. No. 5,239,717; U.S. Pat. No. 4,683,601; U.S. Pat. No. 4,270,235; U.S. Pat. No. 5,214,814; U.S. Patent Des. 331,520; and U.S. Patent Des. 318,923.
In these respects, the portable pillow according to the present invention substantially departs from the conventional concepts and designs of the prior art, and in so doing provides an apparatus primarily developed for the purpose of allowing a user to comfortably rest his or her head in awkward and cramped areas.


A process is disclosed for preparing a protein by a eukaryote transformed by multicopy integration of an expression vector into the genome of a yeast, such as Saccharomyces, Hansenula, and Kluyveromyces, or of a mould such as Aspergillus, Rhizopus and Trichoderma, the expression vector containing both an "expressible gene" encoding the protein and a so-called "deficient selection marker needed for the growth of the yeast or mould in a specific medium", such as the LEU2d, TRP1d or URA3d gene, in combination with a ribosomal DNA sequence, resulting in stable high copy integration of 100-300 copies per cell. This multicopy integration results in an increased production of the desired protein, which can be guar .alpha.-galactosidase, an oxidase or a hydrolytic enzyme such as a lipase.

An example of a so-called "deficient selection marker needed for the growth of the yeast" is the LEU2d gene described by Kingsman c.s. (reference 1), who described the development of a multicopy integrative vector which was dispersed throughout the genome using the transposable Ty element Ty1-15 (reference 2). The element was engineered to contain two selectable markers, TRP1 (reference 3) and LEU2 from pMA3a, and the PGK expression signals from pMA91 (reference 4) with an IFN-.alpha..sub.2 coding sequence (reference 5). A single copy of the engineered Ty was integrated into the genome using a linear fragment to stimulate recombination across the ends of the element and thereby replacing an endogenous element. Transformants were selected for the TRP1 marker. Few transformants were obtained by selecting for LEU2 as insufficient enzyme was produced by a single copy of this gene. The transformant was then grown in decreasing concentrations of leucine to select for an increase in the copy number of the LEU2 gene, presumably by spread of the Ty element throughout the genome by gene conversion and transposition (reference 6). A strain was constructed which produced 8.times.10.sup.5 molecules of IFN per cell; this being intermediate between yields from single copy ARS/CEN vectors (10.sup.5 molecules/cell) and from multicopy vectors such as pMA91 (6.times.10.sup.6 molecules/cell).
For a practical stable production system with a transformed yeast the use of Ty elements has certain disadvantages.
Therefore a need exists for other systems by which multicopy integration of heterologous genes in fungi such as yeast and moulds can be achieved.

Process for preparing a protein by a fungus transformed by multicopy integration of an expression vector


A continuous flow mobility classifier provide the ability to perform two-dimensional separation in mass spectrometry. An ionization system is used to ionize a sample. A differential mobility analyzer (DMA) (e.g., a nano-radial DMA) is coupled to the ionization system and to a mass spectrometer. The nano-RDMA is configured to separate the ionized sample by mobility for subsequent mass analysis by the mass spectrometer.

1. Field of the Invention
The present invention relates generally to mass spectrometry, and in particular, to a method, apparatus, and article of manufacture for integrating a differential mobility analyzer with a mass spectrometer.
2. Description of the Related Art
(Note: This application references a number of different publications as indicated throughout the specification by reference numbers enclosed in brackets, e.g., [x]. A list of these different publications ordered according to these reference numbers can be found below in the section entitled "References." Each of these publications is incorporated by reference herein.)
Two dimensional separation in mass spectrometry (MS) is an area under constant development. The analysis of mixtures often demands separation of the mixture before final analysis owing to the complexity of the mixture. Many techniques in mass spectrometry already exist and are well suited to mixture analysis. Liquid chromatography-mass spectrometry (LC-MS) is a widely used technique that has the greatest utility in pre-separating protein digests prior to mass spectrometry analysis. Ion mobility spectrometry mass spectrometry (IMS-MS) is an example of a two dimensional separation where the first dimension is the mobility of the ion and the second dimension is the mass of that ion.
The aforementioned preseparations operate in the time domain wherein a sample that is introduced at the entrance of the preseparation device are separated into fractions that arrive at the mass spectrometer entrance at times that vary according to specific physico-chemical properties of the analyte. A fast mass spectrometric analytical method such as time-of-flight mass spectrometry may be able to analyze the entire range of possible mass-to-charge-ratios on a time that is short compared to the time resolution of the preseparation method, but slower mass spectrometric methods may only be able to resolve a limited range of mass to charge ratios. If, however, the preseparation is capable of continuously transmitting a selected fraction of the sample, slower mass spectrometric methods may be able to resolve all of the components of the fraction. One example of such a continuous preseparation is field assymetric waveform ion mobility spectrometry (FAIMS™) which transmits molecules with mobilities within a narrow range of values to the mass spectrometer for sufficient time to resolve the analytes of interest within selected ion mobility fractions of the original sample.
While research implementations of mobility-MS experiments have been in existence for some time, commercial instrumentation for achieving mass-mobility measurements is nonetheless part of the state of the art in mass spectrometry instrumentation. Instrument companies have invested considerable dollars in the development of the latest class of instruments with mobility front ends. Advances in electronics and fabrication methods have finally enabled the mass production of such instruments on a scale commensurate with implementation in commercial laboratories. Examples of such instruments include Waters™ SYNAPT™ instruments and Thermo Scientific™ instruments using a field asymmetric waveform ion mobility spectrometry (FAIMS™) interface, as well as a number of instruments from smaller manufacturers. The fact that such research and development funding has been committed to the development of mobility-mass measurement is indicative that such instruments are desired and must continually be developed.
Accordingly, what is needed is a hybrid mass mobility instrument with a front-end mobility separation device. To better understand the problems of the prior art, a description of prior art mass spectrometry techniques is useful.
Mass spectrometry is an analytical technique used to identify unknown compounds, the isotopic composition of elements in a molecule and to determine the structure of a compound. Such identification is performed by measuring the mass-to-charge ratio of charged particles which can be used to determine the particle's mass, the composition of a sample, and/or the chemical structure of the sample/molecule.
In an MS process, a sample is loaded onto an instrument where it is vaporized (i.e., transitioned into a gas from a solid or liquid). The result is then ionized by a variety of methods to form charged particles (ions). The ions are separated by their mass-to-charge ratio in an analyzer, detected, and the ion signal is processed into mass spectra.
An MS instrument used to perform the above process may include an ion source, a mass analyzer, and a detector. The ion source is used to perform the vaporization and the ionization of the material under analysis (the analyte). Electrospray ionization (EI), where liquid containing the analyte is dispersed by electrospray into a fine aerosol, may be used during the ionization process. The ions are transported to the mass analyzer that sorts the ions by their masses (e.g., by applying electromagnetic fields). The detector measures the quantity of ions.
As described above, chromatographic techniques may be combined with MS to separate different compounds before analysis by the MS. LC-MS separates a liquid analyte (e.g., in combination with ES) before introducing the compound to the ion source and MS. IMS-MS first separates ions by drift time through a neutral gas under an applied electrical potential gradient before being introduced into an MS.
Embodiments of the present invention provide the ability to perform mobility separation before mass analysis by an MS. As set forth in the detailed description below, various different types of differential mobility analyzers (DMAs) may be used. For example, radial DMAs (RDMAs) may be used in one or more embodiments of the invention. Previously, a nano-RDMA device was presented and mobility values for various tetraalkylammonium ions were reported [1][7][8]. The previous experiment used an electrometer detection scheme where all ion current exiting the device was measured. However, prior art systems fail to integrate nano-RDMAs with an MS in an effective manner. Further, the prior art fails to integrate MS with DMAs that operate with flow rates that are compatible with general analytical laboratory operations.

Continuous flow mobility classifier interface with mass spectrometer


A fairing panel retainer can include a retainer strip that is configured to conform to the contour of a vehicle body. The retainer strip includes alternating body attachment segments and raised panel attachment segments in a generally corrugated configuration. In addition, each of the body attachment segments includes a body fastener interface configured to accept a permanent fixed fastener to attach the fairing panel retainer to the vehicle body. Each of the panel attachment segments can include a panel fastener interface, for example, a bore through the panel attachment segment and a fastener plate slidably attached to a lower surface of the panel attachment segment. The body fastener interfaces and the panel fastener interfaces can be closely aligned along a longitudinal line or arc of the retainer strip. The fairing panel retainer can also include a transition surface to provide a smooth transition from the vehicle body surface to a fairing panel.

A fairing is a member or structure whose primary function is to produce a smooth outline and to reduce aerodynamic drag. A fairing can join two surfaces so that the external surfaces blend smoothly. Fairings can be used on vehicles of all types, from motorcycles to airplanes, as well as on the exterior of other structures, such as buildings. For example, fairings can be used to cover otherwise open areas on the exterior of a vehicle or structure. A fairing also can be used to cover equipment or components installed on a vehicle that require periodic access.
As a specific example, a large fairing surface can be installed on some airplanes underneath the fuselage near the attachment point of the wings. One some airplanes, auxiliary equipment, such as a pressurization and environmental control system, inert gas generator, main landing gear or ram air turbine, can be is installed in this locale. The fairing provides a covering on the underside of the airplane with a smooth transition from the external fuselage surface to the fairing surface. A fairing can include a single, undivided surface, or a fairing can include multiple fairing panels attached to a frame structure. As another example, a protective fairing surface can be installed over a radar antenna on an airplane.
In some existing configurations, edge fairing panels can be directly attached to a vehicle body surface using fasteners. In other existing configurations, edge fairing panels can be attached to an angular frame that is fastened to the vehicle body and forms an edge of the fairing surface. In such a configuration, the fasteners that attach the angular frame to the vehicle body can sometimes be significantly misaligned with the fasteners that attach the fairing panels to the angular frame, which can cause a significant moment to be transferred to the vehicle body structure, resulting from an aerodynamic force on the fairing panel. In addition, the corner formed by the angular frame can sometimes have a relatively abrupt edge that can disturb aerodynamic flow over the external surface of the fairing panels.
Accordingly, it is desirable to provide a method and apparatus that attaches a fairing panel to a vehicle body, in some instances producing a smooth aerodynamic transition from the vehicle body surface to the fairing panel surface, without transferring a substantial moment resulting from the aerodynamic force on the fairing panel to the vehicle body structure.


A system and method are provided for providing an improved inker unit surface cleaning and conditioning system, including in a single anilox chamber blade system, for improving image quality, including eliminating ghosting, in a proposed variable data digital lithographic image forming architecture. Techniques are provided to remove acquired oil from an inking member. A particularly-configured containment encloses a cleaner (disturber) roller to emulsify the acquired oil on the inking roller. The cleaner roller is preferably configured with a pliable surface including a silicon roller surface over a porous base. The silicon roller (1) absorbs dampening solution oil; and (2) agitates ink that may be still held in certain cells/cavities of the inking member or roller. In embodiments, a vacuum pressure is applied to the inside of the hollow cleaner roller to better remove the residual ink and dampening solution from the inking roller.

1. Field of Disclosed Subject Matter
This disclosure relates to systems and methods for providing an improved inker unit surface cleaning and conditioning system, including in a single anilox chamber blade system, for improving image quality, including eliminating ghosting, in a proposed variable data digital lithographic image forming architecture.
2. Related Art
U.S. Patent Application Publication No. 2012/0103212 A1 (the 212 Publication) published May 3, 2012 and based on U.S. patent application Ser. No. 13/095,714, which is commonly assigned and the disclosure of which is incorporated by reference herein in its entirety, proposes systems and methods for providing variable data lithographic and offset lithographic printing or image receiving medium marking in image forming system. The systems and methods disclosed in the 212 Publication are directed to improvements on various aspects of previously-attempted variable data imaging lithographic marking concepts to achieve effective truly variable digital data lithographic printing.
According to the 212 Publication, a reimageable surface is provided on an imaging member, which may be a drum, plate, belt or the like. The reimageable surface may be composed of, for example, a class of materials commonly referred to as silicones, including polydimethylsiloxane (PDMS) among others. The reimageable surface may be formed of a relatively thin layer over a mounting layer, a thickness of the relatively thin layer being selected to balance printing or marking performance, durability and manufacturability.
The 212 Publication describes, in requisite detail, an exemplary variable data lithography system 100 such as that shown, for example, in FIG. 1. A general description of the exemplary system 100 shown in FIG. 1 is provided here. Additional details regarding individual components and/or subsystems shown in the exemplary system 100 of FIG. 1 may be found in the 212 Publication.
As shown in FIG. 1, the exemplary system 100 may include an imaging member 110. The imaging member 110 in the embodiment shown in FIG. 1 is a drum, but this exemplary depiction should not be read in a manner that precludes the imaging member 110 being a plate or a belt, or of another known configuration. The imaging member 110 is used to apply an inked image to an image receiving media substrate 114 at a transfer nip 112. The transfer nip 112 is produced by an impression roller 118, as part of an image transfer mechanism 160, exerting pressure in the direction of the imaging member 110. The exemplary system 100 may be used for producing images on a wide variety of image receiving media substrates 114. The 212 Publication also explains the wide latitude of marking (printing) materials that may be used, including marking materials with pigment densities greater than 10% by weight. As does the 212 Publication, this disclosure will use the term ink to refer to a broad range of printing or marking materials to include those which are commonly understood to be inks, pigments, and other materials which may be applied by the exemplary system 100 to produce an output image on the image receiving media substrate 114.
The 212 Publication depicts and describes details of the imaging member 110 including the imaging member 110 being comprised of a reimageable surface layer formed over a structural mounting layer that may be, for example, a cylindrical core, or one or more structural layers over a cylindrical core.
The exemplary system 100 includes a dampening solution subsystem 120 generally comprising a series of rollers, which may be considered as dampening rollers or a dampening unit, for uniformly wetting the reimageable surface of the imaging member 110 with dampening solution. A purpose of the dampening solution subsystem 120 is to deliver a layer of dampening solution, generally having a uniform and controlled thickness, to the reimageable surface of the imaging member 110.
Once the dampening solution is metered onto the reimageable surface of the imaging member 110, a thickness of the dampening solution may be measured using a sensor 125 that may provide feedback to control the metering of the dampening solution onto the reimageable surface of the imaging member 110 by the dampening solution subsystem 120.
Once a precise and uniform amount of dampening solution is provided by the dampening solution subsystem 120 on the reimageable surface of the imaging member 110, and optical patterning subsystem 130 may be used to selectively form a latent image in the uniform dampening solution layer by image-wise patterning the dampening solution layer using, for example, laser energy. The reimageable surface of the imaging member 110 should ideally absorb most of the laser energy emitted from the optical patterning subsystem 130 close to the surface to minimize energy wasted in heating the dampening solution and to minimize lateral spreading of heat in order to maintain a high spatial resolution capability. While the optical patterning subsystem 130 is described above as being a laser emitter, it should be understood that a variety of different systems may be used to deliver the optical energy to pattern the dampening solution.
The mechanics at work in the patterning process undertaken by the optical patterning subsystem 130 of the exemplary system 100 are described in detail with reference to FIG. 5 in the 212 Publication. Briefly, the application of optical patterning energy from the optical patterning subsystem 130 results in selective evaporation of portions of the layer of dampening solution.
Following patterning of the dampening solution layer by the optical patterning subsystem 130, the patterned layer over the reimageable surface of the imaging member 110 is presented to an inker subsystem 140. The inker subsystem 140 is used to apply a uniform layer of ink over the layer of dampening solution and the reimageable surface layer of the imaging member 110. The inker subsystem 140 may use an anilox roller to meter an ink onto one or more ink forming rollers that are in contact with the reimageable surface layer of the imaging member 110. Separately, the inker subsystem 140 may include other traditional elements such as a series of metering rollers to provide a precise feed rate of ink to the reimageable surface. The inker subsystem 140 may deposit the ink to the pockets representing the imaged portions of the reimageable surface, while ink deposited on the unformatted portions of the dampening solution will not adhere based on the hydrophobic and/or oleophobic nature of those portions.
The cohesiveness and viscosity of the ink residing in the reimageable layer of the imaging member 110 may be modified by a number of mechanisms. One such mechanism may involve the use of a rheology (complex viscoelastic modulus) control subsystem 150. The rheology control system 150 may form a partial crosslinking core of the ink on the reimageable surface to, for example, increase ink cohesive strength relative to the reimageable surface layer. Curing mechanisms may include optical or photo curing, heat curing, drying, or various forms of chemical curing. Cooling may be used to modify rheology as well via multiple physical cooling mechanisms, as well as via chemical cooling.
The ink is then transferred from the reimageable surface of the imaging member 110 to a substrate of image receiving medium 114 using a transfer subsystem 160. The transfer occurs as the substrate 114 is passed through a transfer nip 112 between the imaging member 110 and an impression roller 118 such that the ink within the voids of the reimageable surface of the imaging member 110 is brought into physical contact with the substrate 114. With the adhesion of the ink having been modified by the rheology control system 150, modified adhesion of the ink causes the ink to adhere to the substrate 114 and to separate from the reimageable surface of the imaging member 110. Careful control of the temperature and pressure conditions at the transfer nip 112 may allow transfer efficiencies for the ink from the reimageable surface of the imaging member 110 to the substrate 114 to exceed 95%. While it is possible that some dampening solution may also wet substrate 114, the volume of such a dampening solution will be minimal, and will rapidly evaporate or be absorbed by the substrate 114.

Systems and methods for implementing an advanced inker unit surface conditioning system in a variable data digital lithographic printing device


A method for determining a contribution of a processing apparatus to a fingerprint of a parameter across a substrate, the method including: obtaining a delta image which relates to a difference between a first pupil image associated with inspection of a first feature on the substrate and a second pupil image associated with inspection of a second feature on the substrate, wherein the first and second features have different dose sensitivities; determining a rate of change of the difference in response to a variation of a dose used to form the first and second features; selecting a plurality of pixels within the delta image having a rate of change above a predetermined threshold; and determining the contribution using the determined rate of change and the delta image restricted to the plurality of pixels.

A lithographic apparatus is a machine constructed to apply a desired pattern onto a substrate. A lithographic apparatus can be used, for example, in the manufacture of integrated circuits (ICs). A lithographic apparatus may, for example, project a pattern (also often referred to as "design layout" or "design") at a patterning device (e.g., a mask) onto a layer of radiation-sensitive material (resist) provided on a substrate (e.g., a wafer).
To project a pattern on a substrate a lithographic apparatus may use electromagnetic radiation. The wavelength of this radiation determines the minimum size of features which can be formed on the substrate. Typical wavelengths currently in use are 365 nm (i-line), 248 nm, 193 nm and 13.5 nm. A lithographic apparatus, which uses extreme ultraviolet (EUV) radiation, having a wavelength within the range 4-20 nm, for example 6.7 nm or 13.5 nm, may be used to form smaller features on a substrate than a lithographic apparatus which uses, for example, radiation with a wavelength of 193 nm.
Low-k1 lithography may be used to process features with dimensions smaller than the classical resolution limit of a lithographic apparatus. In such process, the resolution formula may be expressed as CD=k1×λ/NA, where λ is the wavelength of radiation employed, NA is the numerical aperture of the projection optics in the lithographic apparatus, CD is the "critical dimension" (generally the smallest feature size printed, but in this case half-pitch) and k1 is an empirical resolution factor. In general, the smaller k1 the more difficult it becomes to reproduce the pattern on the substrate that resembles the shape and dimensions planned by a circuit designer in order to achieve particular electrical functionality and performance. To overcome these difficulties, sophisticated fine-tuning steps may be applied to the lithographic projection apparatus and/or design layout. These include, for example, but not limited to, optimization of NA, customized illumination schemes, use of phase shifting patterning devices, various optimization of the design layout such as optical proximity correction (OPC, sometimes also referred to as "optical and process correction") in the design layout, or other methods generally defined as "resolution enhancement techniques" (RET). Alternatively, tight control loops for controlling a stability of the lithographic apparatus may be used to improve reproduction of the pattern at low k1.
A typical semiconductor fabrication process will include the basic steps of: depositing a film of photoresist (film deposition); baking the photoresist; exposing the photoresist to provide the requisite pattern; developing the exposed resist and etch the substrate. Fluctuations of the process may lead to undesired variation in the critical dimensions across the substrate and hence worsening of the critical dimension uniformity, CDU. CDU is a key parameter for assuring good performance and reliable functionality of any integrated circuit and maximizing this measure is a continual goal within the semiconductor fabrication industry.
The variation introduced by each process step may be unique to that process step and may be referred to as a fingerprint. The accumulative variation of all of the processing steps may be referred to as the combined fingerprint.
Various metrology methods are known for determining the combined fingerprint. One method includes determining the critical dimension uniformity by measuring the various parameters in the post-processed substrate and comparing the measurements to libraries of functions to determine the critical dimensions. This is a time consuming and difficult method which is computationally extensive and typically includes significant inaccuracies. An exemplary metrology method may use a process map to describe how the after-etch process varies across the wafer. The process map is based on the CD critical dimension measurements of anchor features obtained using a CDSEM tool.
The present invention seeks to provide an improved way to determine a contribution of a processing apparatus is to a parameter of a processed substrate and also seeks to provide an improved calibration and control techniques.

Method of determining the contribution of a processing apparatus to a substrate parameter


In a paper sheet conveying operation for a plotter, a roller paper sheet 29 supported on a feeding roller 35 is slackened by way of rotation of the feeding roller. The suspended portion of the paper sheet is pulled up onto the platen 34 due to rotation of the drive roller 10. Then, the suspended portion of the paper sheet 29 passes through a pair of tension rollers 27 and 28 and receives weak tension from the tension rollers 27 and 28, thus preventing the paper sheet from snaking. When the tension rollers are not placed correctly in parallel to the Y-rail of the plotter, the distances of the left and right edges of the paper sheet from the tension rollers to the drive roller become unequal. Consequently, unequal tensions are generated in the opposing edges of the paper sheet when it passes between the tension rollers 27 and 28, thereby causing a discrepancy in the conveyance of the paper sheet 29. Solving the problem, a route length control mechanism is provided on the supporting portion of the tension rollers 27 and 28. As a result, the distances of the left and right edges of the paper sheet between the tension rollers 27, 28 and the drive roller 10 can be controlled and made substantially equal.

The present invention relates to a rolled paper sheet conveying apparatus of a plotter using a paper roll and a rolled paper conveying route control method.
Conventionally, a plotter using paper rolls of an automatic drafting machine is known. The important point of such plotter is that the rolled paper sheet is pulled out to a platen of the automatic drafting machine with a uniform tension on left and right edges of the sheet and rolled around a winding means with a uniform tension effective along the transverse direction of the sheet. Attaining such uniform tension on a sheet to be enables the sheet supplied to a correct and precise position on the platen.
In order to obtain a construction of the rolled paper conveying apparatus of the plotter enabling to attain uniform tension on both edges of the sheet, it has been necessary to manufacture respective parts and assemble them with high precision. This is because lengths of left and right conveying routes of the rolled paper must be equal to each other, and a drafting roller, a feeding roller (feeding means), and a winding roller (winding means) must be arranged in a three-dimensional parallel relation.
It is noted that it is very difficult to always obtain a high degree of precision in manufacturing the parts and assembling them with a reasonable cost. If high degree precision is attained in the parts and their assembly, it is very difficult to keep the precision for a long period of usage and in transportation of the plotter.
It has been found that when a predetermined range for one frame of the sheet paper in the plotter is made suspended, after a upon drawing the sheet paper, taking the sheet from the winding roller, by a feeding operation of a drive roller and winding the no-tensioned suspended sheet onto the winding roller, sheet winding error, generated from a small installation error of the winding roller and a front tension roller placed up-stream of the winding roller, can be controlled or diminished by a flange of the winding roller.
Feeding roller installation error can be solved by paying out a sheet part of the rolled paper through a feeding roller so as to make the sheet part slacken, and then pulling up the slackened sheet part onto the platen through the drive roller so as to convey the sheet correctly.
However, this conventional idea has the shortcoming as that only slackening the paper and pulling up it by the drive roller causes some snake-motion of the running sheet.
In order to prevent the running paper sheet from being snaked, the plotter has been provided with a set of tension rollers on its legs so as to give weak tension to the sheet placed at its feeding side. When the installation axis of the tension roller is not perfectly parallel to a Y-axis of the tension roller, it is difficult or impossible to precisely convey the paper sheet onto the platen.

Rolled sheet conveying apparatus of plotter and rolled sheet conveying route control method.


Systems and methods are provided for identifying combinatorial feature interactions, including capturing statistical dependencies between categorical variables, with the statistical dependencies being stored in a computer readable storage medium. A model is selected based on the statistical dependencies using a neighborhood estimation strategy, with the neighborhood estimation strategy including generating sets of arbitrarily high-order feature interactions using at least one rule forest and optimizing one or more likelihood functions. A damped mean-field approach is applied to the model to obtain parameters of a Markov random field (MRF); a sparse high-order semi-restricted MRF is produced by adding a hidden layer to the MRF; indirect long-range dependencies between feature groups are modeled using the sparse high-order semi-restricted MRF; and a combinatorial dependency structure between variables is output.

1. Technical Field
The present invention relates to interactions between transcription factor binding, and more particularly, to a sparse high-order Boltzmann Machine for identifying combinatorial interactions between transcription factors.
2. Description of the Related Art
Identifying combinatorial relationships between transcription factors (TFs) maps the data mining task of discovering the statistical dependency between categorical variables. Model selection in high dimensional discrete case has been a traditionally challenging task. Recently, an approach of generative structure learning is to impose an L1 penalty on the parameters of the model, and to find a Maximum a posteriori probability (MAP) parameter estimate. The L1 penalty causes many of the parameters, corresponding to edge features, to go to zero, resulting in a sparse graph.
This was originally explored for modeling continuous data with Gaussian Markov Random Fields (MRFs) in two variants. In the Markov Blanket (MB) variant, the method learns a dependency network p(yi|y−i) by fitting d separate regression problems (independently regressing the label of each of the d nodes on all other nodes), and L1-regularization is used to select a sparse neighbor set. Although one can show this is a consistent estimator of topology, the resulting model is not a joint density estimator p(y). In the Random Field (RF) variant, L1-regularization is applied to the elements of the precision matrix to yield sparsity. While the RF variant is more computationally expensive, it yields both a structure and a parameterized model (while the MB variant yields only a structure).
The discrete case is much harder than the Gaussian case, partially because of the potentially intractable normalizing constant. Another complicating factor in the discrete case is that each edge may have multiple parameters. This arises in multistate models as well as conditional random Fields. For modeling discrete data, algorithms have been proposed for the specific case where the data is binary and the edges have Ising potentials, and in the binary-Ising case, there is a 1:1 correspondence between parameters and edges, and this L1 approach is suitable. However, in more general scenarios (including any combination of multi-class MRFs, non-Ising edge potentials), where many features are associated with each edge, there exists a need for block-L1 systems and methods that jointly reduce groups of parameters to zero at the same time to achieve sparsity. Moreover, prior approaches do not reveal higher-order dependencies between variables, such as how the binding activity of one TF can affect the relationship between two other TFs.


A kit features two arm assemblies, each of which features a longitudinal member with a padded portion extending from proximate one end thereof toward the other end and a connection at each end allowing horizontal and pivotal motion of the arm assembly about. A method of mooring a watercraft involves connecting each arm assembly between a respective connection point on the watercraft and a respective securing point on a body distinct therefrom, allowing horizontal pivoting of the arms to horizontally move the watercraft toward a vertical plane in which the securing points lie and blocking further horizontal pivoting of the arms by contact between the watercraft and a respective one of the arm assemblies before the watercraft reaches the vertical plane. The arm assemblies bind due to contact with the watercraft, thereby blocking impact of the watercraft with the body to which the securing points are mounted.

A number of arm-like mooring devices have been developed to secure watercraft to a dock but maintain a distance between the watercraft and dock to prevent damage that otherwise may be caused by impact therebetween. Such devices may be seen in U.S. Pat. No. 5,243,926 of Wright et al., U.S. Pat. No. 6,561,113 of Leise, U.S. Pat. No. 4,686,926 of Vance, U.S. Pat. No. 4,913,078 of Haverly and U.S. Pat. No. 5,450,808 of Beagan.
Prior art mooring devices may be limited in their portability by requiring the installation of a particular mounting mechanism on the watercraft and the dock or other structure to which the watercraft is to be secured. As result, the use of such a mooring device on more than one watercraft or at more than one mooring site may require multiple devices or at least the installation of multiple mounting brackets.

Extendable retractable portable watercraft mooring system


Disclosed herein is an analog-digital converter. The analog-digital converter includes a sample-and-hold amplifier, a first analog-digital converter, a multiple digital-analog converter, a second analog-digital converter, and a digital correction logic. The sample-and-hold amplifier samples an analog input signal using clock boosting. The first analog-digital converter receives a sampled signal, and converts the sampled signal into a plurality of bits of first digital output code. The multiple digital-analog converter receives and stores the sampled signal, and amplifies and outputs the difference between the stored signal and an analog signal corresponding to the first digital output code. The second analog-digital converter receives the output signal of the multiple digital-analog converter, and converts the output signal into a plurality of bits of second digital output code. The digital correction logic receives the first digital output code and the second digital output code, overlaps certain bits of the first digital output code with certain bits of the second digital output code, and outputs remaining bits, exclusive of overlapping bits, as final digital output code.

1. Field of the Invention
The present invention relates generally to an analog-digital converter and, more particularly, to a sample-and-hold amplifier using a clock boosting technique and an analog-digital converter having the sample-and-hold amplifier.
2. Description of the Related Art
Recently, with the development of high density Very Large-Scale Integration (VLSI) processing technology and Digital Signal Processing (DSP) technology, the demand for high performance analog-digital converters to be used in high quality video systems, next generation personal portable communication equipment, high speed digital communication networks and medical equipment is gradually increasing. Furthermore, as the demand for portable equipment is increasing, low power, low voltage analog-digital converters, each of which, together with another Complimentary Metal-Oxide Semiconductor (CMOS) that uses a 1.8 V level low voltage source, can be implemented in a single chip, is under great demand. In particular, in the case of image display applications, such as a flat display input unit and a Liquid Crystal Display (LCD) monitor drive circuit, a sampling rate is equal to or higher than 100 MHz and several-hundred-MHz-level input signals must be processed at a resolution of 8 bits, so that analog-digital converters, to the input terminals of which sample-and-hold amplifiers capable of operating at high speed and sampling high frequency input signals are applied, are essential.
Recently, the market for digital televisions has rapidly expanded. Additionally, Vestigial Side Band (VSB) will be used as the standard for a digital television reception method in Korea. When VSB digital television is received, analog-digital converters are used to digitally process analog television signals.
A conventional method of sampling an analog signal to produce an input for an analog-digital converter is performed using a tuner, a Surface Acoustic Wave (SAW) filter and a mixer, as shown in FIG. 1. Accordingly, this method is disadvantageous in that the unit cost of a digital television board is high because the method should employ a two-stage mixer.
Additionally, the circuit of the method is disadvantageous in that, when a very high input frequency enters in the case where the circuit is used in a sub-sampling analog-digital converter, the operational characteristics of sampling results are deteriorated due to the increase and variation of input impedance, thus causing reduction in performance. Accordingly, it is difficult to obtain a signal of more than 8 bits. As a result, it is difficult to use the circuit of the method in a sub-sampling analog-digital converter.

Analog-digital converter using clock boosting


A disposable device for absorbing perspiration that can be placed into the forehead area of a variety of styles and sizes of headwear. The invention consists of a flexible, liquid absorbent pad made from a material such as cloth having an absorbent nap, such as terry cloth, or absorbent paper, which may be cut by the user to fit the forehead area of the headwear. The absorbent pad may be of varying degrees of thickness. The absorbent pad is coated on one side with an adhesive, which temporarily but firmly adheres the absorbent pad to the headwear. After the absorbent pad becomes soiled, the invention can be removed from headwear by the user, disposed of, and replaced with a new absorbent pad. The non-adhesive side of the absorbent pad may be readily printable, so that advertising, slogans or other messages may be printed thereon.

It is frequently the case that during exercise or other physical exertion, an individual will perspire around the forehead area. If the individual is wearing a hat, cap or other type of headwear, then the perspiration from the forehead area will soil the headwear, making the headwear unsanitary, particularly if the individual is wearing cosmetic preparations or suntan oil. The present invention solves this problem by teaching a device which absorbs perspiration, or other fluids, thus keeping the headwear clean. The invention can be placed in virtually any type of headwear, and removed and disposed of after the invention becomes soiled. Moreover, because the invention can be placed in the forehead area of the headwear, it serves the additional function of preventing perspiration from dripping onto the user's face, and into the users eyes. This is important if the user is participating in a sport requiring hand-eye coordination such as baseball, golf, football, tennis, etc. where perspiration in the users eyes can cause a temporary blindness and consequent loss of performance. This function of the invention is even more important if user is operating heavy equipment, where a temporary loss of sight can be a serious safety hazard.

Self-adhering absorbent disposable pads for headwear


A skin is provided for the user interface of a mobile communication device. The skin is obtained by providing a data file including information defining characteristics of the skin, providing a markup language style sheet describing a manner in which data is to be represented on a display of the mobile communication device; transforming the data file into a markup language document according to the markup language style sheet, and providing the markup language document to an user interface application to represent the data on the display.

1. Field of the Invention
The present invention relates generally to user interfaces in mobile communication devices. Particular aspects of the invention relate to methods of providing skins for the user interface of a mobile communication device.
2. Discussion of the Related Art
With some software written for desktop and laptop computers, various aspects and features of the user interface, such as graphical elements, icons, animations, colors, texture, fonts, sounds, etc., can be easily changed all at the same time. The changes can be accomplished using data files referred to as "skins", which can be easily downloaded from the Internet and installed without altering the functionality of the software. Skins are available for the Netscape 6 web browser at www.netscape.com, and for the Windows operating system software and various applications software at www.topdesktop.com. Most of the skins are available for free. Even for a skin that is only available for a fee, there is nothing to prevent the skin from being copied and forwarded or distributed to others without payment to the party originally providing the skin. This inhibits the development of an effective commercial market for skins.
The circumstances for customization or personalization are quite different in the field of mobile communications devices, such as cellular phones, personal digital assistants (PDAs), web pads, pagers, cordless telephones, handheld computers, etc. Customization of the user interface is limited to ringing tones, screen savers and simple logos, usually determined by a user profile maintained by the operator of the wireless communication network which the device accesses for communications, and/or exchangeable covers and keypads for the housing of the device such as described in EP 1091540.
Mobile communications devices have been growing rapidly in computing power and can now perform many functions in addition to voice telephony (such as a phonebook, personal organizer, etc). In particular, they are capable of requesting, receiving and displaying information consisting of alphanumeric text or graphics. An example of alphanumeric text is a short message service (SMS) in GSM, which permits the user to send and receive short text messages transmitted through a cellular public land mobile network (PLMN). More recently, mobile communications devices have been developed which allow the user to access documents or graphics data from the Internet or elsewhere using the Wireless Application Protocol (WAP) over wireless communication networks.
WAP enabled devices allow information to be accessed from various remote servers offering data services such as banking, stock quotes, and weather forecasts. Data content is provided in a markup language, such as wireless markup language (WML) or extensible hypertext markup language (XHTML). WML is configured to allow data to be displayed as a deck of individual cards which are of a size suited for display on the relatively small display screen typical. A micro-browser software application is typically provided in the mobile communication device to receive the data and display it in different screens. The user interface of the mobile communication device provides some way for the user to navigate between different display screens.
Since mobile communications devices typically use displays of relatively small size and/or resolution, the degree of user satisfaction depends greatly on the ability to display data in a manner preferred by the user. Since mobile communication devices are typically battery powered, they generally use black and white displays rather than color displays which consume more power. This creates also a disadvantage insofar as color cannot be used to enhance the user interface.
Because of the relatively fixed architecture of mobile communications devices, a user cannot install or change software and there are no skins or other possibilities for the user of a mobile communications device to alter the display of information as there are in the field of desktop or laptop computers. Customization of the user interface according to user preference is limited to ringing tones, screen savers, logos and the use of exchangeable covers for the housing of the device, such as described in EP 1091540.


A method for the detection of an analyte in a fluid, comprising contacting the fluid with a holographic element comprising a medium and a hologram disposed throughout the volume of the medium, wherein an optical characteristic of the element changes as a result of a variation of a physical property occurring throughout the volume of the medium, wherein the variation arises as a result of interaction between the medium and the analyte, and wherein the reaction and the variation are reversible; and detecting any change of the optical characteristic.

A short communication to the International Journal of Optoelectronics 7(3):449-452 (1992), by Spooncer et al, entitled "A humidity sensor using a wavelength-dependent holographic filter with fibre optic links", describes the response of gelatin-based Bragg reflection holograms to ambient humidity. It concludes that optical response to an increasing and decreasing cycle of humidity shows a hysteresis which limits its industrial application as a sensor.
WO-A-9526499 discloses a holographic sensor, based on a volume hologram. This sensor comprises an analyte-sensitive matrix having an optical transducing structure disposed throughout its volume. Because of this physical arrangement of the transducer, the optical signal generated by the sensor is very sensitive to volume changes or structural rearrangements taking place in the analyte-sensitive matrix as a result of interaction or reaction with the analyte. For example, a sensor comprising a gelatin-based holographic medium may be used to detect trypsin. Trypsin acts on the gelatin medium, irreversibly destroying the integrity of the holographic support medium.

Method of detecting an analyte in a fluid


The present invention is to provide a spot-size transformer which can transform the beam spot-size in a waveguide separated by a groove and a waveguide-embedded optical circuit using the spot-size transformer. The spot-size transformer according to the present invention comprises a first optical waveguide having a first core and a first cladding covering substantially the whole surface of the first core, a second optical waveguide having a second core provided as an extension of the first cladding and a second cladding, a transition waveguide positioned between the first and second optical waveguides, the transition waveguide having a first core whose width of the extension becomes gradually narrower as it goes toward the second optical waveguide.

The present invention relates to a spot-size transformer and a method of producing the same, more particularly, to a low-loss spot-size transformer and a method of producing the same. Further, the present invention relates to a waveguide-embedded optical circuit using the spot-size transformer, and particularly to a waveguide-embedded optical circuit that has low loss and can be fabricated at low cost.

Spot-size transformer, method of producing spot-size transformer and waveguide-embedded optical circuit using spot-size transformer