A computer readable transportable information recording medium includes a recordable area and a read only area. The recordable area allows recording of data thereinto and reading of the data therefrom. The read only area stores a copy judging program, an encrypting program, a recording program, a decoding program, a first password control program, and a second password control program. The copy judging program judges whether a transportable information recording medium has been undergone a copy operation. The encrypting program encrypts data designated and stored in a computer. The recording program records the data encrypted by the encrypting program into the recordable area. The decoding program decodes the data encrypted and stored in the recordable area. The first password control program sets or judges a password when the encrypting program is activated. The second password control program judges a password when the decoding program is activated.

1. Field of the Invention
The present invention relates to an apparatus, a method, and a program product for secure data formatting and retrieving and a transportable data recording medium storing the program product, and more particularly to an apparatus, a method, and a program product for secure data formatting and retrieving and a transportable data recording medium storing the program product by arranging a read only area and a recordable area.
2. Discussion of the Background
As both an infrastructure and techniques for networking have rapidly developed in recent years, usage of networks to carry out transmission of digital data has become common. Typical examples are sending e-mail, downloading of digital data from a web site, and sharing of digital data in a local area network, for example.
On the other hand, however, security issues with respect to the digital data has not solved yet, such as information leakage via networks, invasion by virus, and so on. Accordingly, a data transportable medium effective in an offline mode still has an important role. In particular, CD-ROMs including a CD-R and a CD-RW are useful since nearly every personal computer is equipped with an optical disc drive apparatus.
As one variation of the CD-ROM, a hybrid CD-RW has recently been developed, in which a read only area coexists with a recordable area.
It should be aware that even the above-mentioned offline transportable data medium is not perfect from a security view point. For example, the offline medium always has a risk of loss, an illegal usage when it is rent, etc. That is, since the transportability is a nature of the offline medium, it has a risk of information leakage and invasion by virus, just as is facing on the networks, when being away from the user.
Accordingly, protection of digital data recorded on the CD-ROM becomes important, and conventional techniques of an anti-copy and a data encryption are adopted for such purposes. However, these conventional techniques are already-produced tools and users need to develop own techniques to fit them into user's application, which is not an easy task for the users.

Apparatus, method, and program product for secure data formatting and retriving, and computer readable transportable data recording medium storing the program product


A digital level display device wherein the digital input signal is converted into an absolute value and further converted into its logarithm. The peak of the logarithm is detected and latched. A CPU reads the latched peak and converts into it into a signal for display.

1. Field of the Invention
The present invention generally relates to a digital level display device. It particularly relates to a digital level display device effectively used in a compact disk (CD) player, a digital audio tape recorder (DAT), or the like.
2. Background of the Invention
In a PCM recording/reproducing apparatus such as a CD player, a DAT, or the like, an analog audio signal is digitized so as to be recorded on a recording medium. During reproducing, on the other hand, a reproduced digital signal is converted into an analog signal which is sent out as an output. FIG. 2 is a block diagram showing an example of the conventional digital level display device used, for example, for monitoring a level of a digital signal in such a PCM recording/reproducing apparatus as described above.
In the drawing, a conversion circuit 1 converts a signal applied thereto into an absolute value signal representing an absolute value of the digital signal. The absolute value signal produced from the conversion circuit 1 is applied to a peak latch circuit 2 constituted by a register 3 and a comparator 4 so that a peak value of the absolute value signal is detected and latched. A CPU 5 reads the latched value of the peak latch circuit 2 at a predetermined timing, logarithmically converts the readout latched value into a value for indication in decibels (dB), and further converts the logarithmically converted value into a display signal suitable to be displayed. The CPU 5 applies the display signal to a display 8 constituted by a plurality of lamps, a plurality of light emitting diodes (LEDs), or the like, so as to cause the display 8 to display the peak level of the digital signal.
A reset switching device 6 is arranged so that if the reset switching device 6 is turned on, the CPU 5 controls the register 3 so as to clear the peak value latched in the register 3. A selector 7 is arranged so that if the selector 7 is operated, routines having different resolutions in a program of the CPU 5 are changed over from one to another so that the display resolution in the display 8 can be changed, for example, from a resolution of 3 dB to another resolution of 1 dB, or the like.
The CPU 5 is arranged to operate and process a signal on the basis of the program. Therefore, it takes a long time for the CPU 5 to perform a conversion operation in comparison with a period of sampling data. Accordingly, the CPU 5 causes the peak latch circuit 2 to latch the data for a time required for the operation and causes the peak latch circuit 2 to clear the latched value when the CPU 5 has read the data.
Thus, in the conventional digital level display device, the logarithmic conversion as well as the conversion into the display signal are performed by the CPU 5. Therefore, it is necessary to transfer all the bits representing an absolute value of data to the CPU 5. Therefore, there has been such a disadvantage that not only is a load of the CPU 5 made large but also the number of data lines is increased when data is transferred in parallel to the CPU 5 or the transfer time is increased when data is serially transferred to the CPU 5. Further, there has been a further disadvantage that the arrangement of the peak latch circuit becomes complicated.


The present invention relates to a fail-safe skate retarder that applies a braking force proportional to the weight of a rail car entering the retarder. Each segment of the retarder includes a lever mechanism with a pair of levers rotatably joined under the running rail. Each lever holds a braking rail for engaging a wheel of the car. The retarder is normally in a lower, fail-safe position with the brake rails closer together than the width of the wheel. When the car enters the retarder, the wheel forces the brake rails apart into a braking position, and the middle of the lever mechanism rises to lift the running rail and car. A hydraulic power unit and cylinder is activated to raise the middle of the lever mechanism even further to a release position so that the brake rails are spread apart more than the width of the wheel.

Retarders are widely used in railroad marshalling yards to control the speed of the cars as they are being directed to their desired track and location. Controlling car speed is important. Cars should not exceed specific speed limits. Doing so can result in expensive and dangerous derailments. Some cars may need to travel significantly further through the yard than others, and some cars may be significantly heavier than others. Yet, heavier cars can pick up more speed and require more braking force to slow or stop.
Weight-responsive retarders such as the Type F4 skate retarder provide an amount of braking power proportional to the weight of the rail car. Skate retarders prevent cars from leaving the yard, which protects passing trains and surrounding property and persons. Each segment of the retarder includes a pair of levers joined together under the running rail and extending from opposed sides of the running rail. The levers hold a pair of braking rails, one on each side of the running rail. A hydraulic lift is activated to raise the gauge-side lever so that the braking rails are closer together than the width of a car wheel. A car entering the retarder will force the brake rails apart with a force proportional to the weight of the car. This braking force is applied to the sides of the wheels and causes the car to stop. Spreading the brake rails apart causes the levers to rotate about their knuckle joint, and raises the running rail and car against the force of gravity. The heavier the car, the more force needed to lift the car, and the more braking force applied to its wheels.
A problem with conventional F4 weight-responsive skate retarders is that they are not fail-safe. Power must be supplied to the hydraulic unit of the retarder to produce the braking force needed to stop a railroad car. The hydraulic lift moves the brake rails to their operating position. When power is cut off, the brake rails return to an open position that allows cars to pass through the retarder unimpeded. Weather conditions such as lightning strikes or mechanical malfunctions can cause a loss of power to the retarder and lead to dangerous situations in which the skate retarder cannot be used to stop a moving car. Derailments or crashes can occur that result in significant damage to cars, equipment and cargo, expensive clean up and yard downtime, and serious injury or loss of life to railroad personnel.
Another problem with conventional F4 skate retarders is their "power on" time. Power must be supplied to the hydraulic power unit throughout the day to keep the retarder operating. This increases power consumption and wear and tear on component parts such as in the hydraulic system. Leaks of hydraulic fluid are more prevalent, and more frequent maintenance checks and repairs are needed to ensure proper operation of the retarder.
A still further problem with conventional F4 skate retarders is that they are not universal. A right-handed retarder is needed when the braking levers need to be placed on the right-hand rail of the track, and a left-handed retarder is needed when the brake levers need to be on the left-hand rail. These limitations arise due to track spacing and electrical power locations. The railroad tie saddle has a wear plate on only one side. This plate must be located between the lever mechanism and the tie on its downhill side to maintain the proper alignment of the levers and protect the railroad tie from damage. Right-handed and left-handed retarders are not interchangeable, which results in increased inventory and ordering problems.
A still further problem with conventional F4 weight-responsive skate retarders is the disproportionate movement of the levers and their brake rails. Because the hydraulic cylinder is placed at the outer end of the gauge-side lever, when the hydraulic cylinder is deactivated or lowered, the gauge-side lever moves to its release position that allows the rail cars to pass through the retarder unobstructed. When the hydraulic cylinder is lowered, the braking rail mounted to the gauge-side lever moves a lateral distance of about one inch. Yet, the braking rail mounted to the field-side lever remains substantially stationary, which can result in the wheels of a car dragging on the field-side brake rail when in its release position. This causes excessive wear of the field-side brake rail. A great deal of attention and effort is needed to ensure proper alignment between the running rails and the field-side lever brake rail to ensure proper clearance when the retarder is in its lowered release position to minimize potential engagement with the car wheels.
A problem with conventional (non-F4) skate retarders is that they do not apply consistent weight-responsive braking force to the car wheels. Either too much braking power is applied to unloaded or lighter weight cars (causing the cars to derail), or too little braking power is applied to fully loaded or heavier weight cars (failing to slow or stop the car as desired). Both situations can result in loss of life and significant property damage. Skate retarders that are not weight responsive have difficulty applying a proper amount of force to a passing car. A non-weight responsive skate retarder with a low enough brake force to leave a light car on the track needs to be very long in order to stop a heavy, fast moving car. Longer skate retarders tend to be more expensive and reduce the storage capacity of the yard, which reduces the overall efficiency of the yard.
A further problem with non-weight-responsive (non-F4) skate retarders is the need for regular and frequent maintenance to ensure proper spacing and shimming of the brake rails. Because the brake force produced by the retarder is provided by springs, wear of the brake or rails results in a loss of braking power.
A still further problem with conventional skate retarders is maintenance difficulty. Ballast gravel surrounding the retarder prevents easy access to components such as the hydraulic cylinder, and could even jam the lever arms.
The present invention is intended to solve these and other problems.

Fail-safe, weight-responsive skate retarder


The invention discloses an electronically controlled adjustable dumbbell comprising a handle grip, a weight stack, a base, an end cover, an electronic control system and a weight stack locking structure, wherein the weight stack is located below the handle grip. The invention solves the existing problems of adjustable dumbbells as follows: firstly, the operation is so complicated and cumbersome that it is quite difficult to adjust the weight in one try, and the novice who is new to the adjustable dumbbells cannot quickly adjust the weight plate; secondly, visually the product looks too complicated since the number that needs to be adjusted is printed on the cylindrical surface, and half of the numbers on the handle surface are located below the handle grip, which is difficult to see by the user; thirdly, the lack of modernity and inadequate aesthetics hinders product sales and makes it difficult to make profit quickly.

Adjustable dumbbell is a kind of physical training device, and at present, has the following problems: firstly, the operation is so complicated and cumbersome that it is quite difficult to adjust the weight in one try, and the novice who is new to the adjustable dumbbells cannot quickly adjust the weight plate, resulting in wrong operation and unsuccessful weight plate adjustment, and even causing damage to the product in some cases and inconvenience to the users; secondly, visually the product looks too complicated since the number that needs to be adjusted is printed on the cylindrical surface, and half of the numbers on the handle surface are located below the handle grip, which is difficult to see by the user; thirdly, the lack of modernity and inadequate aesthetics hinders product sales, making it difficult to make profit quickly.

Electronically controlled adjustable dumbbell


The present invention relates to a plug-in wiring structure of the photovoltaic device, which is applicable to thin-strap connection in electric or electronic apparatuses, such as the output connection of copper-made thin bus straps in a package of solar cell plates. The present invention is characterized in a specialized design that includes a U-shaped clip spring with multiple turnings and a U-shaped terminal so as to have a fixed connection of a thin-strap object. According to the inventive connection, the work procedure of packaging solar cell plates can be simplified and high reliability can be achieved in that it is free from tool for disassembly and can be performed with zero drawing force. The present invention is especially applicable to the package of large-scaled photovoltaic generation cell plates having output through multiple bus straps.

1. Field of the Invention
The present invention relates to a plug-in wiring structure of the photovoltaic device.
2. Descriptions of the Related Art
Since the voltage of a single solar cell is relatively low, in the application of solar photovoltaic generation, multiple cells may be connected in certain combination and then packaged to form a photovoltaic device for use in various severe environmental conditions. Regular photovoltaic components, or solar-cell components, are composed of packaging material, a solar-cell serial (parallel) set and a wiring structure. Photovoltaic devices may be connected serially or parallel in certain combination to form a photovoltaic array and, with other auxiliary control apparatuses, form a solar generation station. From the package of the photovoltaic components, there are multiple copper-made thin bus straps introduced to the wiring structure for connection, for which conventional methods includes welding and sectional press bonding.
The method of welding can be performed only with dedicated tools, such as electric irons, and dedicated materials, such as solder wires. Thus, it involves even unfavorable disassembly and replacement since disassembly can be performed only with an electric iron, so that outdoor assembly and maintenance are very difficult.
The method of sectional press bonding has improvement against that of welding, but it has also the following disadvantages. First, assembly and disassembly can be performed only by using a "_"-shaped screwdriver (of restricted specification).
Second, there are defects in the clip spring for press-connection so that the connection area between the clip spring and the bus strap amounts to the cross-sectional area of the clip material merely and a relatively small contact area is formed there between. Furthermore, this sectional contact in the structure (as having been known in the above description), which can make the bus strap broken under pressure and result in rework of the whole package of devices over the cell plate to retrieve the loss.
In view of those disadvantages derived in the application of the conventional wiring structure as described above, the inventor, having years of relevant experience in development practice, endeavored to design and developed a plug-in wiring structure of the photovoltaic device, which attains a level of economical design.

Plug-in wiring structure of optoelectronic device


Back-side MOM/MIM structures are integrated on a device with front-side circuitry. Embodiments include forming a substrate having a front side and a back side that is opposite the front side, the substrate including circuitry on the front side of the substrate; and forming a metal-oxide-metal (MOM) capacitor, a metal-insulator-metal (MIM) capacitor, or a combination thereof on the back side of the substrate. Other embodiments include forming a through-silicon via (TSV), in the substrate, connecting the MOM capacitor, the MIM capacitor, or a combination thereof to the circuitry on the front side of the substrate.

Typically, designers will increase the chip area for a MOM/MIM device layout to enable higher capacitance of the MIM/MOM device in their circuits or applications. The use of larger MOM/MIM layouts may, however, result in an overall increase in chip size and, thus, higher manufacturing costs. Although a thinner dielectric may alternatively be utilized in manufacturing MOM/MIM devices to enable higher capacitance, a potential issue of lower breakdown voltage and higher leakage associated with using a thinner dielectric may lead to an increase in overall circuit leakage and a reduction in terms of circuit performance and reliability.
A need therefore exists for back-side MOM/MIM devices, and enabling methodology.


A vehicle charge inlet integrated into a port assembly surface is provided. The charge inlet includes an inlet housing with a perimeter that is curvilinear, non-cylindrical and shaped so that only a single orientation of a complementary sized and shaped electrical connector may be inserted into the inlet. A plurality of electrical contacts, a latching mechanism and a divider are also integrated into the charge inlet housing, the divider extending from the bottom surface of the inlet housing and configured to fit within a complementary slot of the charge connector, the divider providing further electrical isolation between the electrical contacts. A funneling surface connects the open end of the inlet housing to the port assembly surface.

The charge port for plug-in hybrids (PHEVs) and all-electric vehicles (EVs) is typically externally mounted, thereby allowing easy access and the ability to lock the passenger compartment while the vehicle is being charged. A charge port door, similar to the fuel filler door on a conventional vehicle, is used to protect the charge port from the weather as well as possible tampering.
In general, the physical, electrical and performance requirements as well as the communication protocols used in the conductive charge coupler employed by both PHEVs and EVs in the U.S. follow the recommended practices as provided by the SAE J1772 standard. This standard requires that the charge connector and the vehicle inlet to which the connector is coupled during charging include five contacts. These contacts include a pair of AC power lines, an equipment ground/chassis ground, a control pilot conductor and a proximity sense conductor. The control pilot conductor is the communication link between the vehicle and the charging system that insures that prior to initiating charging, the vehicle is connected, the source is ready to supply charging energy, and the vehicle is ready to accept charging energy. This communication link is also used to determine ventilation requirements, current battery capacity, and to control energy flow throughout the process while monitoring the ground connection. The proximity sense conductor allows the vehicle to detect the presence of the charge connector so that vehicle movement may be prevented when the car is coupled to the charge system.
A variety of charge connector and inlet geometries are currently in use that not only provide the necessary interface connections, but also meet the power delivery, electromagnetic emission, temperature, safety, environmental sealing, ergonomic and latching requirements set by SAE J1772. In general these coupling systems are large and awkward to use, often employing a large cylindrical connector that houses the contact pins and fits within a similarly sized cylindrical inlet. Additionally, a key or similar lead-in feature insures proper orientation of the cylindrical connector into the inlet while a latching mechanism holds the connector in place during charging. While such a connector is functionally adequate, it is cumbersome and difficult to align with the charge inlet, especially under less than ideal conditions such as darkness or inclement weather. Accordingly, what is needed is a charge inlet that simplifies connector alignment. The present invention provides such a charge inlet.


A functionalized polymeric composition, said polymeric composition comprising a first phase and a second phase. The first phase comprises a first copolymer of a monovinylidene monomer and a comonomer selected to have at least one reactive epoxide functionality. The second phase is dispersed with the first phase. The second phase comprises a copolymer of an olefin monomer and one or more ethylenically unsaturated monomers copolymerizable with the olefin monomer wherein at least one of the ethylenically unsaturated monomers copolymerizable with the olefin monomer comprises a reactive functionality capable of reacting with one or more of the reactive epoxide functionalities of the first copolymer.

In the preparation of polymeric compositions formed by the blending of a preformed polymer with another preformed polymer, the compatibility of the resulting copolymers is dependent upon the amount of copolymerizable comonomer incorporated into the copolymer matrix. For example, a copolymer of styrene and glycidyl methacrylate (GMA) may be compatible with a preformed polymer, whereas a different copolymer containing a greater amount or different type of comonomer may be incompatible with the same preformed polymer. In the latter event, blending of the preformed polymer and the comonomer does not result in an improved polymeric composition.
As a consequence of the above described problem, manufacturers who desire to blend two normally incompatible polymers generally polymerize the monomers of one polymer in the presence of the preformed second polymer. During this process, chain transfer, or reaction, with the preformed polymer occurs and some of the first polymer is polymerized from a site on the preformed polymer. The prior art technique is limited to preformed polymers which have active hydrogens capable of being extracted by radicals or reactive groups that can copolymerize with the growing polymer. Most polymers can not be used in this process because of the lack of reactivity. This technique also requires that the preformed polymer be soluble or dispersible in a solvent or monomer system suitable for polymerization of the first monomer.
In view of the deficiencies of the prior art, it would be highly desirable to provide functionalized copolymers capable of reacting with a variety of normally incompatible copolymers.
It would be desirable to provide an improved, economical method for preparing the above polymeric composition, particularly for use in blending the copolymers.
Finally, it would be particularly desirable to provide a functionalized polymeric composition having an elastomeric component for use in preparation of impact resistant blends.

Method of making functionalized polymeric compositions


Described herein are systems, methods, and software to enhance incident response in an information technology (IT) environment. In one example, an incident service identifies a course of action to respond to an incident in the IT environment. The incident service further identifies a particular step in the course of action associated with a credential requirement based on traits associated with the particular step, and generates a credential request to obtain credentials to support the credential requirement.

Information technology (IT) environments often employ various computing components, both physical and virtual, to provide desired operations. These computing elements may include end user computing devices, host computing devices, containers, virtual machines, switches, routers, firewalls, and the like. To maintain efficient and effective operations of the IT environment, incident response services may be employed that can respond to various incidents within the IT environment. These incidents may include or be associated with viruses, malware, spyware, denial of service attacks, phishing attacks, server crashes, device failures, power outages, unknown communications, or some other similar incident.
However, while incident response services provide response operations to incidents within the IT environment, difficulties arise as the size and complexity of the IT environment increases. These difficulties are often compounded when the new computing components provide different operations and are configured with varying hardware and software configurations. Further, the increasing number computing components in combination with limited administrative personnel and resources can make it difficult to manage the investigation and remediation of incidents in the environment. Even with ample administrators or analyst users, it can be cumbersome to coordinate the investigation and remediation efforts.
Overview
The technology described herein improves incident response for an information technology (IT) environment. In one example, an incident service identifies a course of action to respond to an incident in the IT environment. Once identified, the incident service may identify traits of the steps that comprise the course of action, and determine credential requirements based on the traits. The incident service may further generate a request to obtain credentials to accommodate the credential requirement and execute the course of action.

Identification of runtime credential requirements


Described are passenger seats including a lower frame comprising a pair of supports, a seat pan adjustably coupled to the pair of supports via a coupling system, and a rear leg coupled to the lower frame, wherein the rear leg includes an extension component that is configured to adjust a height of the rear leg. The passenger seat may be adjusted into a bed position by compressing the rear leg, adjusting the seat pan into a forward position relative to the lower frame, and reclining the seat back until the seat back is substantially proximate the lower frame.

Many common carriers, such as passenger airlines, bus lines, and train lines, include premium seats that offer a variety of seat positions from the most upright to a full flat or lie flat bed position. In an upright position, a bottom cushion of the seat is typically positioned at a height of approximately 15 to 19 inches from a vehicle floor. When the seat is transitioned to the bed position, the bottom cushion is still approximately 15 to 19 inches from the vehicle floor or slightly lower.
Because these seats are often placed in rows of at least two seats, an access path must be provided for passengers seated in a non-aisle seat. Conventionally, the access path is provided by leaving access space between the seat and the next forward seat when the seat is in the full flat or lie flat bed position. As a result, a greater distance between seats is required, thus reducing the total number of seats that may be placed in a vehicle cabin. As a result, it may be desirable to provide a seat with a full flat or lie flat bed position that does not require additional access space between the seat and the next forward seat.


A LIDAR scanning system having a rotating multifaceted polygon mirror for transmitting modulated light from one of its facets to a surface. Diffuse light reflected off said surface is received by another facet of the polygon mirror and reflected to a photo detector. The phase difference between the transmitted and received light is then used to compute the range of the surface from the scanning system. The intensity of the returned light is used to create a gray scale image of the surface. The use of separate optical paths for the transmitted and returned light, and a small scanned field of view results in an improved signal-to-noise ratio.

This invention relates to a Light Distancing and Ranging scanner (LIDAR) and particularly to a LIDAR scanner employing a rotating polygon mirror for directing the scanned and received light.
Three-dimensional imaging systems have improved the performance of a wide variety of automation systems. While three-dimensional images can be computed from multiple sets of two-dimensional images, this approach is more complex and less accurate than systems which collect images that are fundamentally three-dimensional. In general, these systems collect large amounts of three-dimensional coordinate data from visible surfaces in a scene. This data consists of image data points that explicitly represent scene surface geometry of each sampled point by utilizing range information for each point.
One approach to three-dimensional vision is the "time of light" approach which measures the range at given points by measuring the timing of the return of a pulse of light projected on a target. Unfortunately, the extreme electronic speed required for this approach severely limits the resolution of such systems. LIDAR systems avoid the problems of the time of light approach by modulating a light beam and comparing the modulation of the transmitted and returned signal to determine range. For instance, coherent frequency modulator (FM) LIDAR incorporates frequency modulation/mixing to determine range. However, FM LIDAR systems suffer from the limited frequency modulation capabilities of current laser diodes. Phase shift (AM) LIDAR is a preferred approach which correlates the phase shift between outgoing and incoming amplitude modulated light beams to determine range. As a result, each pixel in a collected image is an individual range measurement, and the resulting image is somewhat like a "terrain map" of the scanned area. When the range information is combined with the two-dimensional image, true three-dimensional vision is accomplished.
A number of difficulties are encountered in the opto-mechanical design of LIDAR systems. One is achieving an acceptable signal-to-noise ratio. For example, LIDAR scanning systems often utilize the same optical path for the transmitted and received light. However, small particles of dirt or scratches in the optical elements, or windows, can cause the transmitted light to be received directly back into the receive optics as noise or crosstalk.
Further, LIDAR systems frequently receive light from the entire scanned volume simultaneously. In these systems the field of view is the same as the scanned volume. This approach, however, yields a relatively small signal-to-noise ratio for a given output of light power. One alternative approach is to receive the reflected radiation via a scanning system so that the field of view of the receiving optical subsystem is very small. This increases the signal-to-noise ratio to permit better accuracy and to allow the use of a lower output light transmitter. Further, in such systems since the transmitted light beam is relatively narrow and the field of view of the receiver optics is narrow, it is easier to construct a system where the outgoing and incoming light beams are not coaxial and do not coincide. One approach, for example, uses dual rotating polygon mirrors, one for transmitting the scanning output beam and the other rotating polygon mirror being employed to receive the incoming reflected light. However, the dual rotating polygon approach presents alignment problems to ensure that the field of view is coincident with the transmitted light.
Thus, it is desirable to provide an improved three-dimensional imaging system which employs amplitude modulated LIDAR with an improved signal-to-noise ratio. Further, it is desirable to provide a LIDAR system in which the transmit and receive beams are not coaxial to reduce unwanted reflections and crosstalk. In addition, it is desirable to have a LIDAR system which employs a small field of view that is scanned along with the transmitted beam and which avoids the use of separate polygons that must be accurately aligned.
A LIDAR scanning system achieving the above-mentioned desirable features is provided according to this invention. The LIDAR scanning system includes a single rotating faceted polygon mirror for receiving and reflecting a transmitted light beam along a linear path as the polygon mirror rotates. Diffuse light reflected from the scanned surface is received by the rotating polygon mirror along an optical path at a small parallax angle relative to the transmitted optical path. The received light is reflected by the rotating polygon mirror and directed to a sensor. The transmitted and returned beams are reflected by adjacent facets of the polygon mirror. In this way, the field of view of the sensor is scanned and is coincident with the point on the object receiving the scanned light.
In accordance with another embodiment of the present invention, the scanning system also employs a tilting mirror which reflects both transmitted and received light for creating a linear scan and receive pattern. The tilting mirror creates scans along multiple positions of the Y-axis to generate a rectangular frame scan.
Additional benefits and advantages of the present invention will become apparent to those skilled in the art to which this invention relates, from the subsequent description of the preferred embodiments and the appended claims, taken in conjunction with the accompanying drawings.


A potting material for an electronic component, an electronic component, and a process for positioning ferrites in an electronic material are disclosed. The potting material is formed by curing a mixture. The mixture includes an epoxy component, an organic amine hardener, a viscosity-controlling agent, and a silica. The potting material has a coefficient of thermal expansion between an inorganic ferrite coefficient of thermal expansion and an organic substrate coefficient of thermal expansion of the electronic component. The potting material includes a rigidity permitting via drilling by one or more of mechanical drilling and laser burning.

Electronic components such as semiconductors are widely used in many products. These components are being miniaturized for high-density semiconductor devices. However, competing with this need for smaller dimensions is the increasing need for functionality that the consumers of semiconductor devices desire. This increase in functionality can affect the size and complexity of the semiconductors and the number of semiconductors per module.
For example, a transmitter-receiver or transceiver installed on a computer, is a device that both transmits and receives analog or digital signals. The basic element of a transceiver is an inductor which is a ferrite routed with insulated conducting metal wires. Current manufacturing technology of transceivers are based on manual wiring of ferrite rings due to the limitation of wiring machines threading through a small ferrite ring. Such manual wiring can limit the ability to miniaturize a transceiver and can result in substantial manufacturing costs.
In electronic components such as transceivers, a thermal coefficient of expansion (TCE) mismatch between interfaces of different materials such as ferrite, potting materials, and substrates becomes serious in particular with the larger integrated circuit (IC) elements, when working with a high TCE, when working with low-cost organic substrates, and/or when working with fine circuitry. Due to the TCE mismatch, temperature cycling excursions generate thermo-mechanical stresses to the interfaces of material between ferrites, organic potting materials, organic substrates, and metal vias. These stresses can degrade a product.
Attempts to embed ferrites in electronic components have been made with epoxy laminates and/or potting materials having rigid molecular structures such as high aramid content. Such laminates and materials have stiffness after being cured which can result in excessive stress. The excessive stress can greatly malfunction ferrites and cause failure modes of cracking and breakage of electronic components. Also, known materials do not flow enough to fill tall structures and can trap air bubbles causing devices to crack during solder reflow cycles.
Potting for electronic components not suffering from the above drawbacks would be desirable in the art.


A railway truck and a bearing adapter therefor which provides improved control of relative movement between a railway truck wheelset and the truck side frames supported thereby.

This invention concerns a railway truck and a flexible roller bearing adapter assembly which provides fit-up between a bearing journal and a side frame in a conventional three-piece railway truck such that the wheelsets can move independently with respect to the side frames as is required to achieve proper wheelset tracking on both curved and tangent track. Various benefits are realized, including reduced flange-to-rail contact and reduced sliding at the interface between the wheel and rail running surfaces.
The invention contemplates a bearing adapter assembly which includes elastomeric elements having a form or geometry that provides for three dimensional support of the side frame pedestals on the bearing journals in a manner that permits necessary and controlled bearing journal translation longitudinally of the side frames in the pedestal opening through differential deformation of the elastomer, including compression thereof. The invention further provides continuously wear-compensated longitudinal and lateral bearing adapter-to-pedestal constraint.
A conventional three piece railway truck is comprised of a pair of laterally spaced side frames which are supported on a pair of longitudinally spaced wheelsets, and an elongated bolster which extends between the spaced side frames and is supported thereon by springs. Practitioners in the art have continuously sought to improve the performance of such trucks in an effort to realize improved truck component service life, reduced rail wear, improved fuel economy and operating reliability, increased safety, and other benefits which can result in overall enhancement of railway rolling stock performance.
As usually furnished commercially, modern railway truck wheelset roller bearings permit only very limited wheelset movement with respect to the side frames. For example, such bearings permit no substantial lateral freedom for the wheelsets to move laterally with respect to the truck side frames. More specifically, it is well known that when a conical wheelset of a conventional truck is displaced laterally on the rails, the wheels roll on unequal radii. The wheel which rolls on the larger radius moves ahead of the other wheel thus steering the wheelset from the laterally displaced position toward the center position, where the wheels roll on equal radii. However, as the wheelset continues on its preferred path, it passes the equilibrium or centered position and moves to a laterally displaced position on the opposite side of center, from which the effect of the wheels rolling on unequal radii again steers the wheelset back toward the centered position. The wheelset thus continuously rolls along a substantially sinusoidal path when there is no sliding at the rail-wheel interface. In order to follow such a sinusoidal path the wheelsets move with respect to the side frames to either a trapezoidal geometry as in radial steering, or a parallelogram geometry such as commonly occurs when the truck warps.
Due to the lack of lateral freedom in the roller bearings, the entire truck will tend to follow such a sinusoidal path. At higher speeds the motion of an empty car body will tend to couple with lateral truck oscillations to produce violent cyclical lateral car body accelerations, commonly known as hunting, which can result in accelerated wear of rail car components and rails as well as other undesirable consequences including lading damage.
Conventional prior art trucks also permit the wheelset bearing journals only very limited longitudinal and rotational freedom in the horizontal plane with respect to the side frame pedestals due to bearing adapter-to-side frame horizontal friction and restricted motion limits. As a result, the wheelsets of prior art trucks have insufficient longitudinal freedom at the side frame pedestals to steer to a radial alignment when traversing curved track. Consequently, the wheelsets tend to slide on the rails when negotiating curved track. The inability of the wheelsets of such trucks to steer thus results in severe frictional rubbing contact between the wheel flanges and the rails, and accelerated flange and rail head wear on shorter radius curves. Under such conditions, fuel economy also suffers as a great deal of energy is dissipated by such rubbing contact. More severe flange rubbing also may create a tendency for the wheel to climb the rail thus precipitating a derailment. Furthermore, improper wheelset tracking on curves may also cause or aggravate track misalignment.
The variable restraining friction and unpredictable motion limits between the bearing journal adapter and the side frame pedestal in conventional trucks also results in tracking energy losses on tangent track. When the wheelsets of a truck cannot achieve a free rolling alignment on tangent track due to asymmetrical tread wear and/or journal-to-pedestal restraint, the resulting wheel tread slip and/or flange rubbing causes increased wheelset rolling energy dissipation.
The art has contemplated trucks which include resilient wheelset journal suspension to provide greater freedom of relative motion than in trucks such as those characterized above. For example, steering trucks are known which use articulating techniques such as mechanical linkage systems, usually in the form of steering arms, for the simultaneous control of both wheelsets in the truck. Nearly all such articulated steering trucks and other known truck designs require resilient journal suspension at the side frame pedestals. However, to be effective the resilient suspension must be sufficiently elastic in horizontal shear to permit the bearing journal to move longitudinally in the pedestal for steering, and must also be sufficiently stiff in the lateral direction so as not to reduce the composite lateral car body-to-truck spring constant and thereby encourage low speed empty car hunting. As a result of these conflicting requirements, known resilient journal suspensions often have yielded either unsatisfactory control at lower empty car speeds or a limited or ineffective steering capability. For example, many prior resilient journal suspensions, commonly the "sandwich" configurations in which elastomer is sandwiched or laminated in alternate layers with a rigid substrate such as a steel plate, the available lateral and longitudinal restraint are identical and therefore unable to accommodate such conflicting requirements as those specified above.
The prior art has also contemplated the use of resilient elastomers in conjunction with the bearing adapters of railway truck wheelsets for load cushioning or shock absorption. Some such prior art pertains to trucks with so-called plane bearings. Patents of interest include U.S. Pat. Nos. 149,284, 301,510, 1,222,698, 1,904,007, 2,234,413, 2,239,646, 2,842,409, 2,957,733, 3,033,617, 3,098,682, 3,222,111, 4,044,689, and 2,207,848. The above cited patents are not generally concerned with journal-to-side frame flexibility for the purpose of wheelset steering.

Railway truck and bearing adapter therefor, and method for controlling relative motion between truck components

A. Stucki Company Division of Hansen, Inc.


Method for the estimation of the heart-rate using photoplethysmography on a body organ, for example a wrist of a user, comprising acquiring optically from said body organ a heart beat signal, acquiring an acceleration signal representative of the acceleration of said body organ, selecting data blocks of said acquired heart beat signal and acceleration signal, compensating said heart beat signal by the acceleration signal, calculating the heart rate value on the basis of said compensated heart beat signal.

Technical Field
The present description relates to techniques for the estimation of the heart-rate.
Various embodiments may apply, e.g., in wearable, in particular wrist-wearable devices, for continuous monitoring of the heart-rate in fitness/wellness applications.
Description of the Related Art
Among the methods for the estimation of the heart-rate in a subject, one of the most employed makes use of optical means to detect heart beat to evaluate the heart-rate, based on photoplethysmography (PPG). Photoplethysmography involves obtaining optically a volumetric measurement of an organ (plethysmogram). A photoplethysmogram is often obtained by using a pulse oximeter which illuminates the skin and measures changes in light absorption. A conventional pulse oximeter monitors the perfusion of blood to the dermis and subcutaneous tissue of the skin.
PPG was historically first employed with finger clips in medical applications. Lately PPG has been employed also on wrist, arm, forearm, to make it suitable for fitness applications.
The PPG techniques typically allow an easy estimation of the heart rate at rest. In motion conditions the PPG signal is affected however by a very low SNR (Signal to Noise Ratio) and SIR (Signal to Interference Ratio). In this specific context SNR means the ratio of the heart rate, e.g., the signal S indicative of the heart rate, to all the other signals, e.g., the noise N. It can be measured by having a subject wearing a cardio frequency meter and a PPG device. The power of the frequency component (peak) measured by the PPG device closest to cardio frequency measured by the cardio frequency meter is the signal S. The total power T is T=(S+N). Thus, for the SNR it is S/N=S/(T−S). The SIR value is obtained as ratio of the signal S over I, the power of the strongest non-cardiac frequency component.
Poor performances are sometimes obtained by processing a PPG signal with known frequency-domain techniques or time-domain techniques, including adaptive filtering techniques.
Thus problems affecting the PPG are strong motion artifacts leading to low SNR, low SIR due to motion artifacts, spikes in the detected signal due to motion.
In the state of the art it is known, in order to compensate the above discussed effects of motion on SNR and SIR and other aspect of the signal detection, to acquire optically from the body organ a heart rate signal, acquire an acceleration signal representative of the acceleration of such body organ, selecting data blocks of said acquired heart rate signal and acceleration signal, compensating in the time domain the heart rate signal by the acceleration signal.
The following publications described similar prior art techniques for the reduction of the artifacts:
Yuta Kuboyama, "Motion Artifact Cancellation for Wearable Photoplethismography Sensor", MIT, 2009;
K. Ashoka eddy, V. Jagadeesh Kumar, "Motion Artifact Reduction in Photoplethysmographic Signals using Singular Value Decomposition", Instrumentation and Measurement Technology Conference, Poland, May 1-3, 2007;
H. Han, M. Kim, J. Kim, "Development of real-time motion artifact reduction algorithm for a wearable photoplethismography", Proceedings of the 29th Annual International Conference of the IEEE EMBS Cite Internationale, Lyon, France, Aug. 23-26, 2007;
P. Wei, R. Guo, J. Zhang, Y. T. Zhang, "A New Wristband Sensor Using Adaptive Reduction Filter to Reduce Motion Artifact", Proceedings of the 5th International Conference on Information Technology and Application in Biomedicine, Shenzen, China, May 30-31, 2008.

Method for the estimation of the heart-rate and corresponding system


The present invention provides a compact, efficient and noiseless alternator for an automotive vehicle which employs a double-layer coil arrangement in a slot for eliminating coil end interference as well as improving the space factor. An automotive alternator comprises a Lundel-type core rotor with 16 poles, and a stator with toothed portions of 96 poles spaced by slots. U-shaped conductor segments are installed in the slots. One portion of the conductor is accommodated in an outer layer portion of a predetermined slot, while the other portion is accommodated in an inner layer portion of a slot phase shifted by an electric angle of 180.degree.. In this manner, all of the slots are separated into the inner and outer layers to accommodate a plurality of conductor segments. These conductor segments are connected only at one side of the stator to form a total of twelve wavy winding coils. These twelve wavy winding coils are divided into three groups each consisting of a serial connection of four wavy windings to constitute one phase of a three-phase stator coil.

The present invention relates to an alternator for an automotive vehicle, which is preferably installed in a passenger vehicle, a truck or the like.
Vehicle bodies tend to be formed into slanted nose shapes in order to reduce their aerodynamic resistance. However, a vehicle body is also required to provide enough space for the passenger compartment. To satisfy both requirements, the engine compartments of automotive vehicles have become so narrow and crowded that only limited space is available for installing an alternator. Meanwhile, to improve fuel economy, the rotation rate of the engine tends to be reduced. Correspondingly, the rotation rate of the alternator is lowered. At the same time, however, there is a need to increase electric loads such as safety control devices, etc. Thus, improving the generating ability of the alternator is strongly required. In other words, a compact, powerful, and inexpensive automotive alternator is needed.
Furthermore, it is desirable that noises leaking from vehicles be reduced. Providing a quiet passenger compartment leads to increased product appeal. To this end, engine noises have recently been reduced. However, engine accessories need to rotate at relatively high speeds. Thus, fan noises and magnetic noises of automotive alternators are becoming the main noises emitted from automotive vehicles.
Conventionally, the stator winding generally used in an automotive alternator is arranged by using a continuous wire assembled with a stator core. In such a stator winding arrangement, various improvements have been proposed for satisfying the requirements of compactness, higher output, lower noise, etc.
For example, as disclosed in Published Unexamined Japanese Patent Application No. 7-303351, providing a shorter winding is effective to reduce the winding resistance. According to a 2.pi./3 short-pitch winding technique, the winding is wound without causing interference between phases in a radial direction. However, there is a problem in that the winding factor is substantially worsened and accordingly the generated voltage is greatly reduced. Furthermore, performing such a winding operation is difficult.
According to other proposed techniques, coil ends are pre-shaped or thinned to avoid interference during the winding operation. However, problems arise in that the winding operation is complicated and the winding resistance value is increased. Furthermore, according to these techniques, the interference of the coil ends cannot be solved completely. In each slot, the coil is located in an offset condition where no more than half of a cross section is available as a geometrical space for accommodating the coil. This arrangement results in a drawback because the resistance cannot be reduced. Also, due to the above-described offset arrangement of the coil in the slot, the coil configuration becomes different in each phase, making the resistance value and the inductance of the winding different in each phase. Thus, the flow of current is different in each phase, causing a local temperature increase which may worsen the performance of the alternator and increase the magnetic noise.
As disclosed in Published Unexamined Japanese Patent Application No. 59-159638, the coil end may be formed into a flattened configuration to reduce the air flow resistance. However, according to the arrangement shown in this prior art, the air flow resistance is still high. Sufficient cooling ability cannot be expected, and noise cannot be reduced satisfactorily.
Furthermore, to realize compactness and high output, there is a technique for increasing the magnetic flux by reducing the air gap between the rotor and the stator. However, this technique requires enlarging the cross-sectional area of the stator core in accordance with an increase of the magnetic flux, thereby reducing the slot area and increasing the winding resistance. As a result, the effect of increased output is largely canceled. In short, it is important to optimize the balance between the core and the winding which cooperatively constitute the stator.
To obtain an improved output, an optimization will be attained in the selection of design data for the core cross section and the winding. However, a remaining problem to be solved is cooling of the coil ends which serve as a heat generation source. For example, a large-scale fan will be required for cooling the electric conductors through an insulating film and a fixing member provided on the surface thereof. The fan needs to be disposed adjacent to the coil ends. However, according to a conventional winding, the coil ends are undulated due to the interference between different phases. This increases the higher-order fan noise. When this noise creates a nuisance for vehicle passengers, it must be reduced. For example, the inner face of the coil ends facing the fan may be smoothed as an ideal surface by using a complicated winding method, or the cooling air amount may be reduced by sacrificing fan efficiency.
In the process of seeking compactness and higher output, there will be a problem in that the magnetic noise is increased due to an increased magnetic force acting between the rotor and the stator. In general, an automotive alternator is equipped with a rectifier which cuts the output voltage at a predetermined level to charge a battery. Thus, the generated voltage has a rectangular waveform. It is known that spatial higher harmonics in the clearance between the stator and the rotor chiefly comprise tertiary higher harmonic components. Accordingly, a magnetic force acting between the stator and the rotor comprises the square components of the tertiary higher harmonic components. The magnetic force thus created will generate a magnetic ripple force.
To eliminate such magnetic forces, Published Unexamined Japanese Patent Application No. 4-26345 proposes to use two sets of three-phase windings which are mutually phase shifted by an electric angle of 30.degree.. Two outputs of these two three-phase windings are combined so that their magnetic ripple forces will cancel each other.
However, this conventional winding arrangement cannot solve the coil end interference derived from the conventional winding configuration. The number of required slots is doubled, which requires a careful winding operation for a thin wire wound in the slots. This problem is difficult to solve. Clearly, when compactness and higher output are the object, there are many new problems to be solved.
A stator winding having a continuous wire is widely used in conventional automotive alternators. However, this type of stator winding cannot satisfy all of the requirements above, such as compactness, higher output and lower noise, which are contradictory to each other.
On the other hand, a general large generator, such as an induction-type generator, may comprise two layered conductors accommodated in a stator slot which constitute inner and outer layers disposed in a radial direction of the stator slot. To eliminate the interference between different phases at the coil ends, the conductors of the inner and outer layers are alternately connected.
However, there was a problem in that the above-described larger generator could not be directly used as an automotive alternator. More specifically, the automotive alternator needs to supply electric power to the automotive electric loads during an engine idling condition corresponding to the lowest engine speed region and equivalent to the alternator's rotation range of approximately 1,500 rpm. To this end, it is necessary to generate approximately 15 V, which is equivalent to a sum of a battery voltage and a diode drop, at the above-described rotational speed range, i.e., approximately 1,500 rpm or less. However, for an automotive alternator of 1 to 2 kW used for a general passenger vehicle or a truck, it is difficult to generate 15 V at such a low rotation. The above-described general large induction-type generator has about two conductors per slot which is chiefly dependent on a magnetic flux determined by the physical size. When the number of conductors is as small as two, it is difficult to supply sufficient electric power because an electromotive voltage cannot be obtained satisfactorily at the above-described low rotation region. Furthermore, there is a recent tendency to reduce the idling rotation further in order to improve fuel economy. Responding to such a requirement is difficult for the above-described general large induction-type generator.
To increase output at a low-speed region, it may be possible to employ a multi-polarized arrangement operated by higher frequencies. Toward this end, the above-described general large-scale generator uses a salient rotor having an axial length substantially equal to that of the stator core. According to the salient rotor, the magnetomotive force of each magnetic pole is reduced in response to an increase of the magnetic pole number because of a reduction of wiring space in the rotor. Thus, it is difficult to increase the output. In other words, the above-described automotive alternator cannot attain the required performance.
In general, providing clearance inside the salient rotor is structurally difficult. Thus, there is a problem in that the cooling air cannot be introduced and guided to an inner peripheral surface of the rotor. Furthermore, the cooling air cannot be introduced and guided to a field coil provided in the rotor.
Published Unexamined Japanese Patent Applications No. 62-272836, No. 63-274335 and No. 64-5340 disclose automotive alternators which use U-shaped electric conductors, i.e., so-called conductor bars. However, according to this prior art, a plurality of stator cores are laminated in a circumferential direction so as to form a cylindrical shape. Thus, magnetic resistance increases with respect to the passing direction of the magnetic flux, and the required performance cannot be realized. There are also many problems to be solved, for example, maintaining the practical strength.
PCT document WO 92/06527 proposes an arrangement of an automotive alternator which uses conductor bars for a stator. According to the arrangement shown in this prior art, a total of four electric conductors are disposed in a square shape in each slot. In a slot, clearance is provided between two electric conductors arrayed in a circumferential direction at a coil end. According to a conventional ventilation structure for an automotive alternator, a cooling fan is provided outside a frame, and a ventilation passage is provided for guiding cooling air in the axial direction. On the contrary, according to applicant's ventilation structure, a cooling fan is located inside a frame so that cooling air can be directly supplied to the coil end. With this arrangement, the cooling ability is greatly improved so that compactness and higher output can be realized. Accordingly, providing a clearance between coil ends makes it possible to reduce the air resistance and increase the cooling ability. Furthermore, using the U-shaped conductor bars makes it easy to insert the conductor bars into slots offset by a magnetic pole pitch.
However, according to this arrangement, the cross section of each electric conductor is limited. If the cross section of each electric conductor is increased to reduce the electric resistance and increase the output, then it will not be possible to provide the above-described clearance, which will significantly worsen the cooling ability and formability at the coil end. To secure sufficient clearance, it may be effective to reduce the number of electric conductors from four to two per slot. However, with such a small number of conductors, the device will not be able to generate an output at an idling rotation, i.e., at a low-speed region, and thus cannot be used as an automotive alternator.
U.S. Pat. No. 2,928,963 proposes an AC generator which comprises a stator using conductor bars and a Lundel-type pole core. However, according to this invention, a ventilation structure extends only in an axial direction. This ventilation structure differs from the present general ventilation structure. Furthermore, even in an arrangement shown as another embodiment, no internal fan is provided. In view of the foregoing, it is concluded that no improvement is shown for increasing the cooling ability to realize both compactness and higher output. Furthermore, according to the arrangement disclosed in this prior art, each slot accommodates two conductors. Thus, as described above, it will be difficult to obtain an output in the lower-speed region with such a device.


A fiber-optic gyroscope having a single mode fiber coil for sensing the rotation suffers from drift or fluctuation of scale factor of the output signals owing to spontaneous rotation of polarization of beams propagated in the fiber coil. Thus, two depolarizers are required in front of and at the back of the polarizer to avoid the fluctuation. The depolarizer of prior art consists of two birefringent materials twistedly connected with each other at an about 45.degree. inclination angle between the principal axes of one and the principal axes of the other. A conventional fiber-type depolarizer has two polarization maintaining fibers connected together. A new, simplified depolarizer is proposed. The depolarizer is built by gluing a polarization maintaining fiber to an end of the polarizer with an about 45.degree. inclination angle between the principal axes of the fiber and the principal axes of the polarizer. The depolarizer allows us to dispense with one polarization maintaining fiber and spare the operation for connecting fibers by once.

This application claims the priority of Japanese Patent Applications No. 139899/1992 filed Apr. 30, 1992 and No. 198534/1991 filed, Jul. 12, 1991, which are incorporated herein by reference.
A fiber-optic gyroscope obtains an angular velocity of a sensing coil by utilizing the property that the phase difference between a clockwise-propagated light beam and a counterclockwise-propagated light beam is in proportion to the coil angular velocity. Different modes of fiber-optic gyroscope are known owing to the method how to modulate the light beams; phase-modulating method, frequency modulation method and phase shift method, etc.
Since a fiber-optic gyroscope makes the clockwise-propagated light beam and counterclockwise-propagated light beam interfere each other, both light beams must have the same polarization planes at a detector. Difference of the polarization planes will reduce the power of the interference light beam in proportion to cosine of the angle between the different polarization planes. Furthermore, if the polarization planes are vertical each other, they cannot interfere any more.
The polarization planes must be arranged in the same direction at the detector. Since two degenerated light beams having different polarization planes are propagated in a single mode fiber with the same phase constant, the polarization planes are likely to rotate spontaneously.
To suppress the probable rotation of the polarization planes, an improvement of constructing the fiber coil with polarization maintaining fibers and of polarizing the signal light beam before it is divided into two partial light beams may be proposed. Since the polarization maintaining fiber suppresses the rotation of the polarization planes, it can make two partial light beams interfere on the same polarization plane.
Polarization maintaining fibers are not rotationally symmetric, but asymmetric in an angular direction. Asymmetry is obtained by inserting stress applying parts in a diametrical direction or by deforming cores into an elliptic section. Such asymmetry induces a difference of phase constants between two light beams with different polarization planes. Phase velocity will differ according to the polarization. The polarization maintaining fiber has of course birefringence. Thus, it is often called a birefringence fiber. In this description the polarization maintaining fiber will be used as a synonym of the birefringence fiber.
However, the polarization maintaining fiber is much more expensive than the ordinary single-mode fiber. Such a fiber-optic gyroscope which is fully constructed with the polarization maintaining fiber will be highly expensive. Practical significance is poor.
A fiber coil and most of the optical paths shall be preferably fabricated by ordinary single mode fibers. But ordinary single mode fibers have some problems to be solved. Although they are called single mode fibers, it means that a single phase constant has only a single mode. Actually, there are two modes with different polarization planes vertical to each other which have the same phase constant. Two modes with different polarization planes are ideally independent. But polarization planes may rotate owing to external stress or distortion, because the phase constants are the same. The same phase constants degenerate two modes. They cannot forbid the rotation of the polarization planes. The rotation of the polarization planes will mix two modes which would be ideally independent.
However, two modes have different fluctuations of the phase constants in microscopic scale in spite of the macroscopic equivalence of phase constants. Therefore, when two modes have been propagated by the same distance, effective optical path lengths are different. The difference of the effective optical path lengths will induce a fluctuation of the output of the photodetector.
Clockwise propagated light beam and counterclockwise propagated light beam must experience the same path length rigorously in a fiber-optic gyroscope. In microscopic scale, the fluctuation of the polarization would induce a fluctuation of an optical path length. In order to suppress the fluctuation of the optical path length, it shall be effective to fix the polarization plane to a certain direction by launching the light beam through a polarizer before being divided into clockwise propagated light beam and counterclockwise light beam. Such polarization allows only a single mode with a single polarization plane to pass through the single mode fiber. Since single mode beams propagated in a single mode fiber, the optical path lengths are absolutely the same. The situation would be the same as the polarization maintaining fiber mentioned before, if no rotation of polarization occurred. However, a single mode fiber cannot prevent the light beams from rotating polarization planes. Thus, the preparatory polarization by the polarizer is not sufficient to equalize the optical path lengths in any cases. Two light beams with linear polarization planes are propagated in a fiber coil and pass through the same polarizer in a reverse direction. Owing to a probable rotation of the polarization planes, the polarization planes of the beams are not necessarily coincident with the direction of the optical axis of the polarizer. The inclination angle between the optical axis of the polarizer and the polarization plane of the beam is denoted by .PSI.. The amplitude of the beam passing through the polarizer in the reverse direction reduces in proportion to cos .PSI.. The inclination angles are not necessarily the same for the clockwise propagated beam and counterclockwise propagated beam. Furthermore the inclination angle would change owing to a temperature fluctuation. Since the linearly polarized beams often rotate the polarization planes, the output of the photodetector will fluctuate owing to the polarization rotation. Such a fluctuation of the output of the photodetector will hinder an exact measurement of angular velocity.
Therefore, K. Boehm et al. had proposed a single mode fiber-optic gyroscope having a depolarizer in the optical path besides a polarizer. A depolarizer is a device for depolarize arbitrary linearly polarized or elliptically polarized beams. Depolarized state means that polarization planes are distributed with equal probability into all directions. K. Boehm et al.; "Low-Drift Fiber Gyro Using Superluminescent Diode", ELECTRONICS LETTERS, vol. 17, No. 10, p 352 (1981).
FIG. 15 shows the structure of the fiber-optic gyroscope of Boehm. A light source (1) emits a light beam. The beam passes through a lens (21), a beam splitter (22), a polarizer (23) and a lens (24) and enters an end of an optical fiber (25). The optical system converges the light beam on a small fiber core. The beam is linearly polarized by the polarizer (23). Namely, a mode with a single polarization plane is introduced into the fiber. The fiber (25) is coupled to another fiber (27) by a coupler (26). The coupler (26) divides the beam into a clockwise propagated beam and a counterclockwise propagated beam. The clockwise propagated beam once goes out and passes through a lens (28), a depolarizer (29) and a lens (30). The beam converges on an end of the fiber (27) and is propagated in a fiber coil (4) clockwise. Then the clockwise beam passes through a phase modulator (5). The counterclockwise propagated beam is modulated first by the phase modulator (5) and is propagated in the fiber coil (4) counterclockwise. In brief a clockwise propagated beam and a counterclockwise propagated beam are denoted simply by a CW beam and a CCW beam from now on. The CCW beam passes through the depolarizer (29) at last. A depolarizer is an optical device for depolarizing arbitrary linear polarization or elliptical polarization into non-polarization in which polarization planes are distributed in all directions with equivalent probability. The function of a depolarizer is reverse to that of a polarizer. The depolarizer (29) shown in FIG. 15 is called a Lyot depolarizer. FIG. 16 demonstrates a schematic view of a Lyot depolarizer.
A Lyot depolarizer consists of two birefringent crystals coupled each other. Optical axes of two crystals are twisted by 45 degrees. The thicknesses of the crystals are 1:2 in proportion. The thickness of the crystal, is determined so as to keep a difference of optical path lengths between an ordinary ray and an extraordinary ray surpassing the coherent length of the light. FIG. 16 shows isolated crystals for demonstrating optical axes, but in practice, two crystals are glued together without clearance.
The function of a depolarizer will be briefly explained. A linearly polarized beam (a) enters a first birefringent crystal (Q.sub.1) and is divided into two beams (b) and (c) whose polarization planes are in parallel with the optical axes of the birefringent crystal. One is an ordinary beam and the other is an extraordinary beam. The optical path difference L of two beams in the full length the crystal must be longer than the coherent length of the light. Of course the amplitudes of two beams in the crystal (Q.sub.1) are different. Two independent beams enter a second birefringent crystal (Q.sub.2) whose optical axes are inclined at 45 degrees to that the first crystal (Q.sub.1). Both beams (b) and (c) are in halves divided into ordinary beams (d) and (e) and extraordinary beams (f) and (g). The beam (d) and the beam (f) originated from (b) have the same amplitude. The beam (e) and the beam (g) originated from (c) have the same amplitude also. The polarization of the ordinary beams is designated by X-axis. The polarization of the extraordinary beams is designated by Y-axis. The total energy of the light beams with the polarization in parallel with X-axis is equal to a sum of the energy of the beams (d) and (e). Similarly the total energy of the light beams with the polarization in parallel with Y-axis is equal to a sum of the energy of the beams (f) and (g). The energy of the beams with X-polarization is equal to the energy of the beams with Y-polarization, because they are the same sums of halves of the same amounts. In this case, the reason why the total energy of the beams with the same polarization is given by the sum of energy is because the difference of optical paths of the beams with the same polarization is longer than the coherent length the light. The cross terms in the sum of the amplitudes of the different beams vanish in the expression of energy.
The amplitudes of the beams with X- and Y-polarizations are always the same. Thus, the energy of an arbitrary beam is also equal to that of a corresponding beam with the polarization vertical to the former one. Therefore, all beams with any polarization have the same amplitude in common. This state is a depolarized state. Arbitrary linearly-polarized beams are converted to a depolarized state. Thus arbitrary elliptically polarized beams can be also converted into a depolarized state.
Since the second birefringent crystal is twice as thick as the first one, the differences of the optical path lengths of ordinary beams and extraordinary beams regarding four beams (d), (e), (f) and (g) are the same. The differences are in any cases longer than the coherent length. The ratio of the thicknesses shall not necessarily be 1:2. Other ratios except 1:1 are also allowable. But in this case, every difference of the optical path lengths must be longer than the coherent length.
If we wish to use a thinner depolarizer, a light source with a shorter coherent length shall be required.
The fiber-optic gyroscope shown by FIG. 15 is constructed by single mode fibers, a polarizer and a depolarizer. The polarizer and the depolarizer have been made use of for solving the problem of the variation of the output induced by the rotation of the polarization plane. Besides Boehm, similar fiber-optic gyroscopes with a Lyot depolarizer inserted near a fiber coil have been proposed by other persons.
However, the fiber-optic gyroscope shown by FIG. 15 of Boehm was only a device for experiments constructed in a laboratory. It is not a practical device for practical use. Bulk optical parts have been used for a polarizer, a depolarizer and a beam splitter. Such parts are far bigger than fibers. Besides the bulky parts, lenses must be disposed before and behind the parts in order to transform the beams into wide, uniform plane waves. The big discrete parts will make a device too bulky to be used in a car, or another moving object.
A practical fiber-optic gyroscope shall require to reduce the size of polarizer, depolarizer and beam splitter to compact size at least smaller than a fiber coil.
A depolarizer and a polarizer can be made from optical fibers. The fact has been well known. A beam splitter can also be fabricated by optical fibers. Only fabricating all the optical parts by optical fibers shall allow us to make a practical fiber-optic gyroscope for the first time.
A fiber-made beam splitter can be fabricated by melting parts of two fibers, coupling them on sides and expanding the coupled part to enable them to couple evanescently. Such an evanescent coupling divides the light beam into two partial waves. A length of the coupling should be determined to divide the beam rigorously into halves to two branches of an output side.
A depolarizer can also be made from polarization maintaining fibers. FIG. 17 is a schematic view of the depolarizer constructed by two polarization maintaining fibers whose lengths are 1:2 in proportion. Two polarization maintaining fibers are spliced at ends with optical axes twisting together at about 45 degrees. Lengths of the fibers are determined so that the difference of the optical paths of the beams having different polarization planes in parallel with different optical axes is longer than the coherent length off the light. Black dots show the stress applying parts inserted in the fibers in diametric positions. The line connecting two paired dots is ones of the optical principal direction of the fibers. This axis is denoted by X-axis. The other principal axis, Y-axis is vertical to X-axis. The direction of propagation is Z-axis. X- and Y-axes off one fiber are twisted at 45 degrees to X- and Y-axes of the other fiber at the junction. Although FIG. 17 demonstrates dissembled fibers to show the optical axis and the twisting angle, two fibers are spliced at the junction.
A refractive index of the light beam with a polarization plane in parallel with X-axis ( in short, X-polarization )is denoted by n.sub.x. A refractive index of the beam with Y-polarization is denoted by n.sub.y. L.sub.1 and L.sub.2 are lengths of the fibers. The coherent length of the light source is denoted by h. The parameters require the following inequalities in order to make the fiber coupling a depolarizer; EQU .vertline.n.sub.x -n.sub.y .vertline.L.sub.1 >h(i=1,2).vertline.n.sub.x -n.sub.y .vertline. .vertline.L.sub.2 -L.sub.1 .vertline.>h(1)
As a fiber-made polarizer a coil of a polarization maintaining fiber is known. The coil is fabricated by winding a polarization maintaining fiber around a core several turns. Since a polarization maintaining fiber having birefringence is wound, the micro-bending loss differs regarding the directions of the polarization planes. Thus it allows a single beam with a certain direction of polarization to pass through. The other beam with the other direction of polarization vanishes. Thus the coil works as a polarizer. This is called a fiber-type polarizer.
A compact polarizer utilizing thin metal layers has been proposed. FIG. 18 demonstrates such a polarizer consisting of metal films and dielectric films deposited by turns. Metal films have a thicknesses of several nanometers to tens of nanometers. The dielectric films have a thickness of tens of nanometers to hundreds of nanometers. A light beam shall be introduced into the polarizer with a propagating line parallel with the planes of the films. For example, Japanese patent laying open No. 60-97304 (97304/85) has disclosed such a multilayered polarizer. A beam with a polarization plane parallel with the metal films will soon be attenuated. Only a beam with a polarization vertical to the film planes can pass through the device without loss. Thus the multilayered metal dielectric device acts as a polarizer. The metal dielectric multilayered polarizer can be so small that fibers can be spliced directly to the ends of it.
Of course other polarizer can be used. In the case of a discrete, bulky polarizer, two lenses are used to expand a beam to wide plane wave and to converge the wide wave to a core of a fiber as shown in FIG. 19.
The discrete optical parts shown in FIG. 15; a polarizer, a depolarizer and a beam splitter can be replaced by fiber-type devices, or compact devices. However, such replacement is still insufficient to fabricate a practical fiber-optic gyroscope. The problem of fluctuation of the output has not still fully resolved.
The light beam emitted from a light source is a linearly polarized beam. The polarization plane sometimes rotates by some reasons between a light source and a polarizer. It is difficult to harmonize the polarization of a beam with the optical axis of the polarizer at all times. External magnetic force or external tension would induce accidental rotation of polarization. Discrepancy between the polarization and the optical axis reduces the amplitude of the beam passing through the polarizer. In the case of a discrete polarizer as shown in FIG. 15, an initial adjustment of the axes can easily be carried out by maximizing the output of a photodetector by rotating the bulk, discrete polarizer. However, in the case of a fiber-type polarizer or a metal-dielectric multilayered polarizer, such an initial adjustment would be totally impossible, because no light will pass through the polarizer before it is coupled to fibers but no adjustment could be done after it has been coupled to fibers.
Even if such an initial adjustment of harmonizing the beam polarization with the optical axis of the polarizer is carried out, the polarization planes of beams will sometimes rotate by the variation of temperature or distortion of fibers, since an ordinary single mode fiber cannot prevent the polarization from rotating spontaneously. Rotation of the polarization planes will induce an increase or a decrease of the light beam passing through the polarizer. Therefore, the replacement of a discrete, bulk polarizer by a compact polarizer which can propagate a beam after it has been coupled to fibers would cause a new difficult problem of rotation of the polarization between a light source and a polarizer. No initial adjustment can easily be done. A post-adjustment is fully impossible, since the polarizer has tightly coupled to the fibers.
To solve the difficulty, the Inventors had devised a new compact type optic-fiber gyroscope having another depolarizer between a light source and a polarizer. The newly-added depolarizer can be installed either between a light source and a first fiber coupler or between a first fiber coupler and a polarizer. Such a fiber-optic gyroscope had been disclosed by;
1. Japanese patent laying open No. 2-225616(225616/90) PA1 2. Japanese patent laying open No. 2-225617(225617/90) PA1 3. Japanese patent laying open No. 2-225618(225618/90)
Invention 1 employed a depolarizer having two polarization maintaining fibers coupled by an about 45 degree twisting angle. The ratio of lengths of fibers was 1: 2. The length of the shorter fiber was determined so that the difference of effective optical paths between an ordinary beam and an extraordinary beam ( optical path difference by birefringence, in short) is longer than the coherent length of the light source. Such a depolarizer was well-known and equivalent to the depolarizer demonstrated in FIG. 17.
Invention 2 substantially constructed an effective depolarizer near a light source by positioning a polarization maintaining fiber in front of the light source with the optical axis twisted at about 45 degrees to the polarization of the light emitted from the source. Invention 2 dispensed with another polarization maintaining fiber by making use of the twist between the light source and the fiber.
Invention 3 also substantially constructed an effective depolarizer by positioning a birefringent crystal in front of a light source with the optical axis twisted at about 45 degrees to the polarization of the light emitted from the source. Similarly to invention 1, the polarization of the light source and the birefringence of the crystal constituted an effective depolarizer.
The Inventors believe that another depolarizer should be inserted between a light source and a polarizer, when a single mode fiber exists between a light source and a polarizer. Inventions 1, 2 and 3 were based upon the belief. Such a fiber-optic gyroscope was a novel device, because no prior gyroscope contained two depolarizers.
However, invention 2 and invention 3 required a difficult adjustment of optical axes of fibers or birefringent crystals to a polarization plane of a beam emitted from a source. Invention 1 relied upon an independent depolarizer with two polarization maintaining fibers coupled together with optical axes twisted at about 45 degrees. The fiber-type depolarizer is a simple, reliable depolarizer. However, it required many junction operations; a junction of a single mode fiber to a depolarizer, a junction of a polarizer to a depolarizer and junction between two polarization maintaining fibers; at least three junction operations were required.
Such a problem of junction operations accompanies also another depolarizer coupled to an end of a fiber coil besides the depolarizer before the polarizer. Boehm had proposed a depolarizer utilizing two birefringent crystals as shown in FIG. 15. The crystal depolarizer can easily be replaced by a fiber-type depolarizer having two polarization maintaining fibers. The replacement never alleviates the time of junction operations, because a fiber-type depolarizer requires three junctions, i.e. two junctions between an ordinary single mode fiber and a polarization maintaining fiber and one junction between two polarization maintaining fibers. Especially, the junction operation between two polarization maintaining fibers is very difficult, because the optical axes must be twisted at 45 degrees precisely.
However, junction operations can be simplified. Consideration on the function of a depolarizer allows us to simplify the structure of a depolarizer. One purpose of this invention is to provide a fiber-optic gyroscope having simplified depolarizers. Another purpose of this invention is to provide a fiber-optic gyroscope which enjoys low parts cost and low assembly cost by using simplified depolarizers.

Fiber-optic gyroscope for measuring velocity of an object


Contemporary navigation systems are often tasked with routing a vehicle to a destination, but are poorly equipped to assist with finding a vacancy of a parking opportunity in which the vehicle may be parked. Static information, such as enumeration of parking garages and curbside parking meters, may be frustrating if such parking opportunities have no vacancies. The determination of vacancies with certainty may be difficult to achieve due to the characteristic volatility of parking, in which vacancies may be taken in seconds. Presented herein are navigation device configurations involving probabilistic evaluation of parking routes in a vicinity of a destination that may be generated and compared, optionally weighted by various factors, to identify a parking route with parking opportunities that collectively present a high probability of vacancy as compared with other parking routes, which may be presented to the user and/or appended to a current route of an autonomous vehicle.

Within the field of computing, many scenarios involve a navigation device that facilitates the navigation of a vehicle from a starting point or current location to a destination. For example, a navigation device in an automobile may store or have access to a database of streets, and may fulfill a request for navigation assistance to reach a particular destination by identifying a route between the current location of the automobile and the destination, and then providing directions that the user may follow. The level of assistance may vary among devices and scenarios, such as presenting a simple map of the route to the destination; providing audible and/or haptic cues to guide the user's navigation, and updating the series of cues based on the current location of the automobile; and displaying turn-by-turn instructions on a visible output device, optionally including augmented reality displays that coordinate output with a driver's view of the environment. In some scenarios, the routing may include autonomously controlling the vehicle, such as autonomously driving a vehicle to a destination selected by a non-driving passenger.
Because users often need to park a vehicle near a destination, navigation devices often feature capabilities to assist the user in finding places for parking. For example, a device may display a map of parking opportunities near the destination, such as parking garages and parking lots. Some devices may display additional information about each parking opportunity to assist the user's selection, such as the cost of a parking garage. If the user selects a parking opportunity, the device may adjust a route toward the destination to navigate the vehicle to the selected parking opportunity. In this manner, conventional navigation devices may assist the user not only in navigating to the destination, but in finding parking near the destination for the vehicle.


A cathodic protection system providing substantially complete coverage to individual steel-in-concrete units in a multi-unit structure. The system includes a power supply, an electronic circuit board, a header cable, anode wire in each unit connected to the header cable, an adhesive fiber mat in each unit, and a conductive coating in each unit.

The subject matter herein relates generally to cathodic protection systems and more particularly to cathodic protection systems for steel-in-concrete structures utilizing a constant current rectifier with a voltage limiter.
In order to protect steel-in-concrete structures (such as balconies on condominium units) from cracking, various cathodic protection systems have been utilized. In all such systems, an anode or a string of anodes is either laid on the concrete or embedded in it. The anodes are connected in a circuit containing a rectifier and the steel reinforcing bars. The current from the rectifier is sent through the circuit wiring to the anode at which point it passes through the concrete itself to the reinforcing bars and from there through a negative return cable to the rectifier.
One type of cathodic protection system is sometimes referred to as an overlay system. That system comprises disposing a plurality of flexibly interconnected anodes on the concrete deck or base to be protected and cementing them in place. That system basically consists of applying a conductive paint completely over the surface of the concrete layer containing the reinforcing bars. Thereafter, a series of small diameter platinum wires are attached to the concrete paint layer utilizing strips of self-adhesive fiberglass mesh tape. The mesh is then covered with a layer of conductive paint. The anode system is completed and covers the entire concrete surface excluding a small radius around metal; typically 2 inches in diameter and one inch from the edges. A cosmetic acrylic paint can then be put over the conductive paint. The anodes are connected to a rectifier controller through a header cable.
A need to provide constant, individualized current to each condominium balcony has proven to be necessary for a combination of reasons. The traditional method using the typical cathodic protection rectifier uses a designed amount of protective current supplied to all the combined unit areas. In a residential condominium consisting of many exclusive use units, the cathodic protection rectifier method may: oversupply protective current to some exclusive balcony units, undersupply protective current to other exclusive balcony units, or supply no protective current to a number of balcony units.
There is no way to decipher whether all the unit balconies are receiving the design current or any protective current at all. An oversupply of current results in the burning of the anode, causing separation of the anode from the concrete—resulting in little ongoing protection. An undersupply of current or no supply of current allows for the corrosion to continue. Given these issues, there exists a need for customizable current protection without destructive testing. The disclosed invention achieves this goal by having an adjustable rectifier installed into each condominium receptacle area, where the direct current supplied varies according to the specific need of each unique unit.

Cathodic protection system and miniaturized constant current rectifier


In an embodiment, a reactor for carrying out a melt transesterification reaction at a reactor temperature of 160 to 300° C. and a reactor pressure of 5 to 200 mbar, comprises a cylindrical tank comprising a top, a side, and a bottom, wherein the bottom is convex, extending away from the top; a stirring shaft disposed within the cylindrical tank along an axis thereof so that it is rotatable from outside of the cylindrical tank; a stirring blade extending from the stirring shaft in the cylindrical tank; a reactant solution inlet located on the bottom; and a reaction solution outlet located on the bottom. The reactor can be used for the polymerization of a polycarbonate oligomer.

Polycarbonate is widely used in many engineering applications as it has excellent mechanical properties, such as impact resistance and heat resistance, and also has excellent transparency. In a typical method that is industrially used for producing polycarbonate, a bisphenol, such as Bisphenol A (BPA), and a carbonate precursor, such as diphenyl carbonate (DPC), are reacted in an ester exchange method in a molten state. This melt polymerization is often referred to as a melt polycondensation process or transesterification process. The resulting polycarbonate can be extruded or otherwise processed, and can be combined with additives such as dyes and UV stabilizers.
The melt polymerization process though can result in polycarbonates having an increased yellowness index. Methods of preparing polycarbonate with increased control of the polymerization are therefore desired.

Oligomeriser with an improved feed system